1 //===--- SemaDecl.cpp - Semantic Analysis for Declarations ----------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file implements semantic analysis for declarations.
12 //===----------------------------------------------------------------------===//
14 #include "clang/Sema/SemaInternal.h"
15 #include "TypeLocBuilder.h"
16 #include "clang/AST/ASTConsumer.h"
17 #include "clang/AST/ASTContext.h"
18 #include "clang/AST/ASTLambda.h"
19 #include "clang/AST/CXXInheritance.h"
20 #include "clang/AST/CharUnits.h"
21 #include "clang/AST/CommentDiagnostic.h"
22 #include "clang/AST/DeclCXX.h"
23 #include "clang/AST/DeclObjC.h"
24 #include "clang/AST/DeclTemplate.h"
25 #include "clang/AST/EvaluatedExprVisitor.h"
26 #include "clang/AST/ExprCXX.h"
27 #include "clang/AST/StmtCXX.h"
28 #include "clang/Basic/Builtins.h"
29 #include "clang/Basic/PartialDiagnostic.h"
30 #include "clang/Basic/SourceManager.h"
31 #include "clang/Basic/TargetInfo.h"
32 #include "clang/Lex/HeaderSearch.h" // TODO: Sema shouldn't depend on Lex
33 #include "clang/Lex/Lexer.h" // TODO: Extract static functions to fix layering.
34 #include "clang/Lex/ModuleLoader.h" // TODO: Sema shouldn't depend on Lex
35 #include "clang/Lex/Preprocessor.h" // Included for isCodeCompletionEnabled()
36 #include "clang/Sema/CXXFieldCollector.h"
37 #include "clang/Sema/DeclSpec.h"
38 #include "clang/Sema/DelayedDiagnostic.h"
39 #include "clang/Sema/Initialization.h"
40 #include "clang/Sema/Lookup.h"
41 #include "clang/Sema/ParsedTemplate.h"
42 #include "clang/Sema/Scope.h"
43 #include "clang/Sema/ScopeInfo.h"
44 #include "clang/Sema/Template.h"
45 #include "llvm/ADT/SmallString.h"
46 #include "llvm/ADT/Triple.h"
51 using namespace clang;
54 Sema::DeclGroupPtrTy Sema::ConvertDeclToDeclGroup(Decl *Ptr, Decl *OwnedType) {
56 Decl *Group[2] = { OwnedType, Ptr };
57 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, Group, 2));
60 return DeclGroupPtrTy::make(DeclGroupRef(Ptr));
65 class TypeNameValidatorCCC : public CorrectionCandidateCallback {
67 TypeNameValidatorCCC(bool AllowInvalid, bool WantClass=false,
68 bool AllowTemplates=false)
69 : AllowInvalidDecl(AllowInvalid), WantClassName(WantClass),
70 AllowClassTemplates(AllowTemplates) {
71 WantExpressionKeywords = false;
72 WantCXXNamedCasts = false;
73 WantRemainingKeywords = false;
76 bool ValidateCandidate(const TypoCorrection &candidate) override {
77 if (NamedDecl *ND = candidate.getCorrectionDecl()) {
78 bool IsType = isa<TypeDecl>(ND) || isa<ObjCInterfaceDecl>(ND);
79 bool AllowedTemplate = AllowClassTemplates && isa<ClassTemplateDecl>(ND);
80 return (IsType || AllowedTemplate) &&
81 (AllowInvalidDecl || !ND->isInvalidDecl());
83 return !WantClassName && candidate.isKeyword();
87 bool AllowInvalidDecl;
89 bool AllowClassTemplates;
92 } // end anonymous namespace
94 /// \brief Determine whether the token kind starts a simple-type-specifier.
95 bool Sema::isSimpleTypeSpecifier(tok::TokenKind Kind) const {
97 // FIXME: Take into account the current language when deciding whether a
98 // token kind is a valid type specifier
101 case tok::kw___int64:
102 case tok::kw___int128:
104 case tok::kw_unsigned:
111 case tok::kw___float128:
112 case tok::kw_wchar_t:
114 case tok::kw___underlying_type:
115 case tok::kw___auto_type:
118 case tok::annot_typename:
119 case tok::kw_char16_t:
120 case tok::kw_char32_t:
122 case tok::annot_decltype:
123 case tok::kw_decltype:
124 return getLangOpts().CPlusPlus;
134 enum class UnqualifiedTypeNameLookupResult {
139 } // end anonymous namespace
141 /// \brief Tries to perform unqualified lookup of the type decls in bases for
143 /// \return \a NotFound if no any decls is found, \a FoundNotType if found not a
144 /// type decl, \a FoundType if only type decls are found.
145 static UnqualifiedTypeNameLookupResult
146 lookupUnqualifiedTypeNameInBase(Sema &S, const IdentifierInfo &II,
147 SourceLocation NameLoc,
148 const CXXRecordDecl *RD) {
149 if (!RD->hasDefinition())
150 return UnqualifiedTypeNameLookupResult::NotFound;
151 // Look for type decls in base classes.
152 UnqualifiedTypeNameLookupResult FoundTypeDecl =
153 UnqualifiedTypeNameLookupResult::NotFound;
154 for (const auto &Base : RD->bases()) {
155 const CXXRecordDecl *BaseRD = nullptr;
156 if (auto *BaseTT = Base.getType()->getAs<TagType>())
157 BaseRD = BaseTT->getAsCXXRecordDecl();
158 else if (auto *TST = Base.getType()->getAs<TemplateSpecializationType>()) {
159 // Look for type decls in dependent base classes that have known primary
161 if (!TST || !TST->isDependentType())
163 auto *TD = TST->getTemplateName().getAsTemplateDecl();
166 if (auto *BasePrimaryTemplate =
167 dyn_cast_or_null<CXXRecordDecl>(TD->getTemplatedDecl())) {
168 if (BasePrimaryTemplate->getCanonicalDecl() != RD->getCanonicalDecl())
169 BaseRD = BasePrimaryTemplate;
170 else if (auto *CTD = dyn_cast<ClassTemplateDecl>(TD)) {
171 if (const ClassTemplatePartialSpecializationDecl *PS =
172 CTD->findPartialSpecialization(Base.getType()))
173 if (PS->getCanonicalDecl() != RD->getCanonicalDecl())
179 for (NamedDecl *ND : BaseRD->lookup(&II)) {
180 if (!isa<TypeDecl>(ND))
181 return UnqualifiedTypeNameLookupResult::FoundNonType;
182 FoundTypeDecl = UnqualifiedTypeNameLookupResult::FoundType;
184 if (FoundTypeDecl == UnqualifiedTypeNameLookupResult::NotFound) {
185 switch (lookupUnqualifiedTypeNameInBase(S, II, NameLoc, BaseRD)) {
186 case UnqualifiedTypeNameLookupResult::FoundNonType:
187 return UnqualifiedTypeNameLookupResult::FoundNonType;
188 case UnqualifiedTypeNameLookupResult::FoundType:
189 FoundTypeDecl = UnqualifiedTypeNameLookupResult::FoundType;
191 case UnqualifiedTypeNameLookupResult::NotFound:
198 return FoundTypeDecl;
201 static ParsedType recoverFromTypeInKnownDependentBase(Sema &S,
202 const IdentifierInfo &II,
203 SourceLocation NameLoc) {
204 // Lookup in the parent class template context, if any.
205 const CXXRecordDecl *RD = nullptr;
206 UnqualifiedTypeNameLookupResult FoundTypeDecl =
207 UnqualifiedTypeNameLookupResult::NotFound;
208 for (DeclContext *DC = S.CurContext;
209 DC && FoundTypeDecl == UnqualifiedTypeNameLookupResult::NotFound;
210 DC = DC->getParent()) {
211 // Look for type decls in dependent base classes that have known primary
213 RD = dyn_cast<CXXRecordDecl>(DC);
214 if (RD && RD->getDescribedClassTemplate())
215 FoundTypeDecl = lookupUnqualifiedTypeNameInBase(S, II, NameLoc, RD);
217 if (FoundTypeDecl != UnqualifiedTypeNameLookupResult::FoundType)
220 // We found some types in dependent base classes. Recover as if the user
221 // wrote 'typename MyClass::II' instead of 'II'. We'll fully resolve the
222 // lookup during template instantiation.
223 S.Diag(NameLoc, diag::ext_found_via_dependent_bases_lookup) << &II;
225 ASTContext &Context = S.Context;
226 auto *NNS = NestedNameSpecifier::Create(Context, nullptr, false,
227 cast<Type>(Context.getRecordType(RD)));
228 QualType T = Context.getDependentNameType(ETK_Typename, NNS, &II);
231 SS.MakeTrivial(Context, NNS, SourceRange(NameLoc));
233 TypeLocBuilder Builder;
234 DependentNameTypeLoc DepTL = Builder.push<DependentNameTypeLoc>(T);
235 DepTL.setNameLoc(NameLoc);
236 DepTL.setElaboratedKeywordLoc(SourceLocation());
237 DepTL.setQualifierLoc(SS.getWithLocInContext(Context));
238 return S.CreateParsedType(T, Builder.getTypeSourceInfo(Context, T));
241 /// \brief If the identifier refers to a type name within this scope,
242 /// return the declaration of that type.
244 /// This routine performs ordinary name lookup of the identifier II
245 /// within the given scope, with optional C++ scope specifier SS, to
246 /// determine whether the name refers to a type. If so, returns an
247 /// opaque pointer (actually a QualType) corresponding to that
248 /// type. Otherwise, returns NULL.
249 ParsedType Sema::getTypeName(const IdentifierInfo &II, SourceLocation NameLoc,
250 Scope *S, CXXScopeSpec *SS,
251 bool isClassName, bool HasTrailingDot,
252 ParsedType ObjectTypePtr,
253 bool IsCtorOrDtorName,
254 bool WantNontrivialTypeSourceInfo,
255 IdentifierInfo **CorrectedII) {
256 // Determine where we will perform name lookup.
257 DeclContext *LookupCtx = nullptr;
259 QualType ObjectType = ObjectTypePtr.get();
260 if (ObjectType->isRecordType())
261 LookupCtx = computeDeclContext(ObjectType);
262 } else if (SS && SS->isNotEmpty()) {
263 LookupCtx = computeDeclContext(*SS, false);
266 if (isDependentScopeSpecifier(*SS)) {
268 // A qualified-id that refers to a type and in which the
269 // nested-name-specifier depends on a template-parameter (14.6.2)
270 // shall be prefixed by the keyword typename to indicate that the
271 // qualified-id denotes a type, forming an
272 // elaborated-type-specifier (7.1.5.3).
274 // We therefore do not perform any name lookup if the result would
275 // refer to a member of an unknown specialization.
276 if (!isClassName && !IsCtorOrDtorName)
279 // We know from the grammar that this name refers to a type,
280 // so build a dependent node to describe the type.
281 if (WantNontrivialTypeSourceInfo)
282 return ActOnTypenameType(S, SourceLocation(), *SS, II, NameLoc).get();
284 NestedNameSpecifierLoc QualifierLoc = SS->getWithLocInContext(Context);
285 QualType T = CheckTypenameType(ETK_None, SourceLocation(), QualifierLoc,
287 return ParsedType::make(T);
293 if (!LookupCtx->isDependentContext() &&
294 RequireCompleteDeclContext(*SS, LookupCtx))
298 // FIXME: LookupNestedNameSpecifierName isn't the right kind of
299 // lookup for class-names.
300 LookupNameKind Kind = isClassName ? LookupNestedNameSpecifierName :
302 LookupResult Result(*this, &II, NameLoc, Kind);
304 // Perform "qualified" name lookup into the declaration context we
305 // computed, which is either the type of the base of a member access
306 // expression or the declaration context associated with a prior
307 // nested-name-specifier.
308 LookupQualifiedName(Result, LookupCtx);
310 if (ObjectTypePtr && Result.empty()) {
311 // C++ [basic.lookup.classref]p3:
312 // If the unqualified-id is ~type-name, the type-name is looked up
313 // in the context of the entire postfix-expression. If the type T of
314 // the object expression is of a class type C, the type-name is also
315 // looked up in the scope of class C. At least one of the lookups shall
316 // find a name that refers to (possibly cv-qualified) T.
317 LookupName(Result, S);
320 // Perform unqualified name lookup.
321 LookupName(Result, S);
323 // For unqualified lookup in a class template in MSVC mode, look into
324 // dependent base classes where the primary class template is known.
325 if (Result.empty() && getLangOpts().MSVCCompat && (!SS || SS->isEmpty())) {
326 if (ParsedType TypeInBase =
327 recoverFromTypeInKnownDependentBase(*this, II, NameLoc))
332 NamedDecl *IIDecl = nullptr;
333 switch (Result.getResultKind()) {
334 case LookupResult::NotFound:
335 case LookupResult::NotFoundInCurrentInstantiation:
337 TypoCorrection Correction = CorrectTypo(
338 Result.getLookupNameInfo(), Kind, S, SS,
339 llvm::make_unique<TypeNameValidatorCCC>(true, isClassName),
341 IdentifierInfo *NewII = Correction.getCorrectionAsIdentifierInfo();
343 bool MemberOfUnknownSpecialization;
344 UnqualifiedId TemplateName;
345 TemplateName.setIdentifier(NewII, NameLoc);
346 NestedNameSpecifier *NNS = Correction.getCorrectionSpecifier();
347 CXXScopeSpec NewSS, *NewSSPtr = SS;
349 NewSS.MakeTrivial(Context, NNS, SourceRange(NameLoc));
352 if (Correction && (NNS || NewII != &II) &&
353 // Ignore a correction to a template type as the to-be-corrected
354 // identifier is not a template (typo correction for template names
355 // is handled elsewhere).
356 !(getLangOpts().CPlusPlus && NewSSPtr &&
357 isTemplateName(S, *NewSSPtr, false, TemplateName, nullptr, false,
358 Template, MemberOfUnknownSpecialization))) {
359 ParsedType Ty = getTypeName(*NewII, NameLoc, S, NewSSPtr,
360 isClassName, HasTrailingDot, ObjectTypePtr,
362 WantNontrivialTypeSourceInfo);
364 diagnoseTypo(Correction,
365 PDiag(diag::err_unknown_type_or_class_name_suggest)
366 << Result.getLookupName() << isClassName);
368 SS->MakeTrivial(Context, NNS, SourceRange(NameLoc));
369 *CorrectedII = NewII;
374 // If typo correction failed or was not performed, fall through
375 case LookupResult::FoundOverloaded:
376 case LookupResult::FoundUnresolvedValue:
377 Result.suppressDiagnostics();
380 case LookupResult::Ambiguous:
381 // Recover from type-hiding ambiguities by hiding the type. We'll
382 // do the lookup again when looking for an object, and we can
383 // diagnose the error then. If we don't do this, then the error
384 // about hiding the type will be immediately followed by an error
385 // that only makes sense if the identifier was treated like a type.
386 if (Result.getAmbiguityKind() == LookupResult::AmbiguousTagHiding) {
387 Result.suppressDiagnostics();
391 // Look to see if we have a type anywhere in the list of results.
392 for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end();
393 Res != ResEnd; ++Res) {
394 if (isa<TypeDecl>(*Res) || isa<ObjCInterfaceDecl>(*Res)) {
396 (*Res)->getLocation().getRawEncoding() <
397 IIDecl->getLocation().getRawEncoding())
403 // None of the entities we found is a type, so there is no way
404 // to even assume that the result is a type. In this case, don't
405 // complain about the ambiguity. The parser will either try to
406 // perform this lookup again (e.g., as an object name), which
407 // will produce the ambiguity, or will complain that it expected
409 Result.suppressDiagnostics();
413 // We found a type within the ambiguous lookup; diagnose the
414 // ambiguity and then return that type. This might be the right
415 // answer, or it might not be, but it suppresses any attempt to
416 // perform the name lookup again.
419 case LookupResult::Found:
420 IIDecl = Result.getFoundDecl();
424 assert(IIDecl && "Didn't find decl");
427 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) {
428 DiagnoseUseOfDecl(IIDecl, NameLoc);
430 T = Context.getTypeDeclType(TD);
431 MarkAnyDeclReferenced(TD->getLocation(), TD, /*OdrUse=*/false);
433 // NOTE: avoid constructing an ElaboratedType(Loc) if this is a
434 // constructor or destructor name (in such a case, the scope specifier
435 // will be attached to the enclosing Expr or Decl node).
436 if (SS && SS->isNotEmpty() && !IsCtorOrDtorName) {
437 if (WantNontrivialTypeSourceInfo) {
438 // Construct a type with type-source information.
439 TypeLocBuilder Builder;
440 Builder.pushTypeSpec(T).setNameLoc(NameLoc);
442 T = getElaboratedType(ETK_None, *SS, T);
443 ElaboratedTypeLoc ElabTL = Builder.push<ElaboratedTypeLoc>(T);
444 ElabTL.setElaboratedKeywordLoc(SourceLocation());
445 ElabTL.setQualifierLoc(SS->getWithLocInContext(Context));
446 return CreateParsedType(T, Builder.getTypeSourceInfo(Context, T));
448 T = getElaboratedType(ETK_None, *SS, T);
451 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) {
452 (void)DiagnoseUseOfDecl(IDecl, NameLoc);
454 T = Context.getObjCInterfaceType(IDecl);
458 // If it's not plausibly a type, suppress diagnostics.
459 Result.suppressDiagnostics();
462 return ParsedType::make(T);
465 // Builds a fake NNS for the given decl context.
466 static NestedNameSpecifier *
467 synthesizeCurrentNestedNameSpecifier(ASTContext &Context, DeclContext *DC) {
468 for (;; DC = DC->getLookupParent()) {
469 DC = DC->getPrimaryContext();
470 auto *ND = dyn_cast<NamespaceDecl>(DC);
471 if (ND && !ND->isInline() && !ND->isAnonymousNamespace())
472 return NestedNameSpecifier::Create(Context, nullptr, ND);
473 else if (auto *RD = dyn_cast<CXXRecordDecl>(DC))
474 return NestedNameSpecifier::Create(Context, nullptr, RD->isTemplateDecl(),
475 RD->getTypeForDecl());
476 else if (isa<TranslationUnitDecl>(DC))
477 return NestedNameSpecifier::GlobalSpecifier(Context);
479 llvm_unreachable("something isn't in TU scope?");
482 /// Find the parent class with dependent bases of the innermost enclosing method
483 /// context. Do not look for enclosing CXXRecordDecls directly, or we will end
484 /// up allowing unqualified dependent type names at class-level, which MSVC
485 /// correctly rejects.
486 static const CXXRecordDecl *
487 findRecordWithDependentBasesOfEnclosingMethod(const DeclContext *DC) {
488 for (; DC && DC->isDependentContext(); DC = DC->getLookupParent()) {
489 DC = DC->getPrimaryContext();
490 if (const auto *MD = dyn_cast<CXXMethodDecl>(DC))
491 if (MD->getParent()->hasAnyDependentBases())
492 return MD->getParent();
497 ParsedType Sema::ActOnMSVCUnknownTypeName(const IdentifierInfo &II,
498 SourceLocation NameLoc,
499 bool IsTemplateTypeArg) {
500 assert(getLangOpts().MSVCCompat && "shouldn't be called in non-MSVC mode");
502 NestedNameSpecifier *NNS = nullptr;
503 if (IsTemplateTypeArg && getCurScope()->isTemplateParamScope()) {
504 // If we weren't able to parse a default template argument, delay lookup
505 // until instantiation time by making a non-dependent DependentTypeName. We
506 // pretend we saw a NestedNameSpecifier referring to the current scope, and
507 // lookup is retried.
508 // FIXME: This hurts our diagnostic quality, since we get errors like "no
509 // type named 'Foo' in 'current_namespace'" when the user didn't write any
511 NNS = synthesizeCurrentNestedNameSpecifier(Context, CurContext);
512 Diag(NameLoc, diag::ext_ms_delayed_template_argument) << &II;
513 } else if (const CXXRecordDecl *RD =
514 findRecordWithDependentBasesOfEnclosingMethod(CurContext)) {
515 // Build a DependentNameType that will perform lookup into RD at
516 // instantiation time.
517 NNS = NestedNameSpecifier::Create(Context, nullptr, RD->isTemplateDecl(),
518 RD->getTypeForDecl());
520 // Diagnose that this identifier was undeclared, and retry the lookup during
521 // template instantiation.
522 Diag(NameLoc, diag::ext_undeclared_unqual_id_with_dependent_base) << &II
525 // This is not a situation that we should recover from.
529 QualType T = Context.getDependentNameType(ETK_None, NNS, &II);
531 // Build type location information. We synthesized the qualifier, so we have
532 // to build a fake NestedNameSpecifierLoc.
533 NestedNameSpecifierLocBuilder NNSLocBuilder;
534 NNSLocBuilder.MakeTrivial(Context, NNS, SourceRange(NameLoc));
535 NestedNameSpecifierLoc QualifierLoc = NNSLocBuilder.getWithLocInContext(Context);
537 TypeLocBuilder Builder;
538 DependentNameTypeLoc DepTL = Builder.push<DependentNameTypeLoc>(T);
539 DepTL.setNameLoc(NameLoc);
540 DepTL.setElaboratedKeywordLoc(SourceLocation());
541 DepTL.setQualifierLoc(QualifierLoc);
542 return CreateParsedType(T, Builder.getTypeSourceInfo(Context, T));
545 /// isTagName() - This method is called *for error recovery purposes only*
546 /// to determine if the specified name is a valid tag name ("struct foo"). If
547 /// so, this returns the TST for the tag corresponding to it (TST_enum,
548 /// TST_union, TST_struct, TST_interface, TST_class). This is used to diagnose
549 /// cases in C where the user forgot to specify the tag.
550 DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) {
551 // Do a tag name lookup in this scope.
552 LookupResult R(*this, &II, SourceLocation(), LookupTagName);
553 LookupName(R, S, false);
554 R.suppressDiagnostics();
555 if (R.getResultKind() == LookupResult::Found)
556 if (const TagDecl *TD = R.getAsSingle<TagDecl>()) {
557 switch (TD->getTagKind()) {
558 case TTK_Struct: return DeclSpec::TST_struct;
559 case TTK_Interface: return DeclSpec::TST_interface;
560 case TTK_Union: return DeclSpec::TST_union;
561 case TTK_Class: return DeclSpec::TST_class;
562 case TTK_Enum: return DeclSpec::TST_enum;
566 return DeclSpec::TST_unspecified;
569 /// isMicrosoftMissingTypename - In Microsoft mode, within class scope,
570 /// if a CXXScopeSpec's type is equal to the type of one of the base classes
571 /// then downgrade the missing typename error to a warning.
572 /// This is needed for MSVC compatibility; Example:
574 /// template<class T> class A {
576 /// typedef int TYPE;
578 /// template<class T> class B : public A<T> {
580 /// A<T>::TYPE a; // no typename required because A<T> is a base class.
583 bool Sema::isMicrosoftMissingTypename(const CXXScopeSpec *SS, Scope *S) {
584 if (CurContext->isRecord()) {
585 if (SS->getScopeRep()->getKind() == NestedNameSpecifier::Super)
588 const Type *Ty = SS->getScopeRep()->getAsType();
590 CXXRecordDecl *RD = cast<CXXRecordDecl>(CurContext);
591 for (const auto &Base : RD->bases())
592 if (Context.hasSameUnqualifiedType(QualType(Ty, 1), Base.getType()))
594 return S->isFunctionPrototypeScope();
596 return CurContext->isFunctionOrMethod() || S->isFunctionPrototypeScope();
599 void Sema::DiagnoseUnknownTypeName(IdentifierInfo *&II,
600 SourceLocation IILoc,
603 ParsedType &SuggestedType,
604 bool AllowClassTemplates) {
605 // We don't have anything to suggest (yet).
606 SuggestedType = nullptr;
608 // There may have been a typo in the name of the type. Look up typo
609 // results, in case we have something that we can suggest.
610 if (TypoCorrection Corrected =
611 CorrectTypo(DeclarationNameInfo(II, IILoc), LookupOrdinaryName, S, SS,
612 llvm::make_unique<TypeNameValidatorCCC>(
613 false, false, AllowClassTemplates),
614 CTK_ErrorRecovery)) {
615 if (Corrected.isKeyword()) {
616 // We corrected to a keyword.
617 diagnoseTypo(Corrected, PDiag(diag::err_unknown_typename_suggest) << II);
618 II = Corrected.getCorrectionAsIdentifierInfo();
620 // We found a similarly-named type or interface; suggest that.
621 if (!SS || !SS->isSet()) {
622 diagnoseTypo(Corrected,
623 PDiag(diag::err_unknown_typename_suggest) << II);
624 } else if (DeclContext *DC = computeDeclContext(*SS, false)) {
625 std::string CorrectedStr(Corrected.getAsString(getLangOpts()));
626 bool DroppedSpecifier = Corrected.WillReplaceSpecifier() &&
627 II->getName().equals(CorrectedStr);
628 diagnoseTypo(Corrected,
629 PDiag(diag::err_unknown_nested_typename_suggest)
630 << II << DC << DroppedSpecifier << SS->getRange());
632 llvm_unreachable("could not have corrected a typo here");
636 if (Corrected.getCorrectionSpecifier())
637 tmpSS.MakeTrivial(Context, Corrected.getCorrectionSpecifier(),
640 getTypeName(*Corrected.getCorrectionAsIdentifierInfo(), IILoc, S,
641 tmpSS.isSet() ? &tmpSS : SS, false, false, nullptr,
642 /*IsCtorOrDtorName=*/false,
643 /*NonTrivialTypeSourceInfo=*/true);
648 if (getLangOpts().CPlusPlus) {
649 // See if II is a class template that the user forgot to pass arguments to.
651 Name.setIdentifier(II, IILoc);
652 CXXScopeSpec EmptySS;
653 TemplateTy TemplateResult;
654 bool MemberOfUnknownSpecialization;
655 if (isTemplateName(S, SS ? *SS : EmptySS, /*hasTemplateKeyword=*/false,
656 Name, nullptr, true, TemplateResult,
657 MemberOfUnknownSpecialization) == TNK_Type_template) {
658 TemplateName TplName = TemplateResult.get();
659 Diag(IILoc, diag::err_template_missing_args) << TplName;
660 if (TemplateDecl *TplDecl = TplName.getAsTemplateDecl()) {
661 Diag(TplDecl->getLocation(), diag::note_template_decl_here)
662 << TplDecl->getTemplateParameters()->getSourceRange();
668 // FIXME: Should we move the logic that tries to recover from a missing tag
669 // (struct, union, enum) from Parser::ParseImplicitInt here, instead?
671 if (!SS || (!SS->isSet() && !SS->isInvalid()))
672 Diag(IILoc, diag::err_unknown_typename) << II;
673 else if (DeclContext *DC = computeDeclContext(*SS, false))
674 Diag(IILoc, diag::err_typename_nested_not_found)
675 << II << DC << SS->getRange();
676 else if (isDependentScopeSpecifier(*SS)) {
677 unsigned DiagID = diag::err_typename_missing;
678 if (getLangOpts().MSVCCompat && isMicrosoftMissingTypename(SS, S))
679 DiagID = diag::ext_typename_missing;
681 Diag(SS->getRange().getBegin(), DiagID)
682 << SS->getScopeRep() << II->getName()
683 << SourceRange(SS->getRange().getBegin(), IILoc)
684 << FixItHint::CreateInsertion(SS->getRange().getBegin(), "typename ");
685 SuggestedType = ActOnTypenameType(S, SourceLocation(),
686 *SS, *II, IILoc).get();
688 assert(SS && SS->isInvalid() &&
689 "Invalid scope specifier has already been diagnosed");
693 /// \brief Determine whether the given result set contains either a type name
695 static bool isResultTypeOrTemplate(LookupResult &R, const Token &NextToken) {
696 bool CheckTemplate = R.getSema().getLangOpts().CPlusPlus &&
697 NextToken.is(tok::less);
699 for (LookupResult::iterator I = R.begin(), IEnd = R.end(); I != IEnd; ++I) {
700 if (isa<TypeDecl>(*I) || isa<ObjCInterfaceDecl>(*I))
703 if (CheckTemplate && isa<TemplateDecl>(*I))
710 static bool isTagTypeWithMissingTag(Sema &SemaRef, LookupResult &Result,
711 Scope *S, CXXScopeSpec &SS,
712 IdentifierInfo *&Name,
713 SourceLocation NameLoc) {
714 LookupResult R(SemaRef, Name, NameLoc, Sema::LookupTagName);
715 SemaRef.LookupParsedName(R, S, &SS);
716 if (TagDecl *Tag = R.getAsSingle<TagDecl>()) {
717 StringRef FixItTagName;
718 switch (Tag->getTagKind()) {
720 FixItTagName = "class ";
724 FixItTagName = "enum ";
728 FixItTagName = "struct ";
732 FixItTagName = "__interface ";
736 FixItTagName = "union ";
740 StringRef TagName = FixItTagName.drop_back();
741 SemaRef.Diag(NameLoc, diag::err_use_of_tag_name_without_tag)
742 << Name << TagName << SemaRef.getLangOpts().CPlusPlus
743 << FixItHint::CreateInsertion(NameLoc, FixItTagName);
745 for (LookupResult::iterator I = Result.begin(), IEnd = Result.end();
747 SemaRef.Diag((*I)->getLocation(), diag::note_decl_hiding_tag_type)
750 // Replace lookup results with just the tag decl.
751 Result.clear(Sema::LookupTagName);
752 SemaRef.LookupParsedName(Result, S, &SS);
759 /// Build a ParsedType for a simple-type-specifier with a nested-name-specifier.
760 static ParsedType buildNestedType(Sema &S, CXXScopeSpec &SS,
761 QualType T, SourceLocation NameLoc) {
762 ASTContext &Context = S.Context;
764 TypeLocBuilder Builder;
765 Builder.pushTypeSpec(T).setNameLoc(NameLoc);
767 T = S.getElaboratedType(ETK_None, SS, T);
768 ElaboratedTypeLoc ElabTL = Builder.push<ElaboratedTypeLoc>(T);
769 ElabTL.setElaboratedKeywordLoc(SourceLocation());
770 ElabTL.setQualifierLoc(SS.getWithLocInContext(Context));
771 return S.CreateParsedType(T, Builder.getTypeSourceInfo(Context, T));
774 Sema::NameClassification
775 Sema::ClassifyName(Scope *S, CXXScopeSpec &SS, IdentifierInfo *&Name,
776 SourceLocation NameLoc, const Token &NextToken,
777 bool IsAddressOfOperand,
778 std::unique_ptr<CorrectionCandidateCallback> CCC) {
779 DeclarationNameInfo NameInfo(Name, NameLoc);
780 ObjCMethodDecl *CurMethod = getCurMethodDecl();
782 if (NextToken.is(tok::coloncolon)) {
783 BuildCXXNestedNameSpecifier(S, *Name, NameLoc, NextToken.getLocation(),
784 QualType(), false, SS, nullptr, false);
787 LookupResult Result(*this, Name, NameLoc, LookupOrdinaryName);
788 LookupParsedName(Result, S, &SS, !CurMethod);
790 // For unqualified lookup in a class template in MSVC mode, look into
791 // dependent base classes where the primary class template is known.
792 if (Result.empty() && SS.isEmpty() && getLangOpts().MSVCCompat) {
793 if (ParsedType TypeInBase =
794 recoverFromTypeInKnownDependentBase(*this, *Name, NameLoc))
798 // Perform lookup for Objective-C instance variables (including automatically
799 // synthesized instance variables), if we're in an Objective-C method.
800 // FIXME: This lookup really, really needs to be folded in to the normal
801 // unqualified lookup mechanism.
802 if (!SS.isSet() && CurMethod && !isResultTypeOrTemplate(Result, NextToken)) {
803 ExprResult E = LookupInObjCMethod(Result, S, Name, true);
804 if (E.get() || E.isInvalid())
808 bool SecondTry = false;
809 bool IsFilteredTemplateName = false;
812 switch (Result.getResultKind()) {
813 case LookupResult::NotFound:
814 // If an unqualified-id is followed by a '(', then we have a function
816 if (!SS.isSet() && NextToken.is(tok::l_paren)) {
817 // In C++, this is an ADL-only call.
819 if (getLangOpts().CPlusPlus)
820 return BuildDeclarationNameExpr(SS, Result, /*ADL=*/true);
823 // If the expression that precedes the parenthesized argument list in a
824 // function call consists solely of an identifier, and if no
825 // declaration is visible for this identifier, the identifier is
826 // implicitly declared exactly as if, in the innermost block containing
827 // the function call, the declaration
829 // extern int identifier ();
833 // We also allow this in C99 as an extension.
834 if (NamedDecl *D = ImplicitlyDefineFunction(NameLoc, *Name, S)) {
836 Result.resolveKind();
837 return BuildDeclarationNameExpr(SS, Result, /*ADL=*/false);
841 // In C, we first see whether there is a tag type by the same name, in
842 // which case it's likely that the user just forgot to write "enum",
843 // "struct", or "union".
844 if (!getLangOpts().CPlusPlus && !SecondTry &&
845 isTagTypeWithMissingTag(*this, Result, S, SS, Name, NameLoc)) {
849 // Perform typo correction to determine if there is another name that is
850 // close to this name.
851 if (!SecondTry && CCC) {
853 if (TypoCorrection Corrected = CorrectTypo(Result.getLookupNameInfo(),
854 Result.getLookupKind(), S,
856 CTK_ErrorRecovery)) {
857 unsigned UnqualifiedDiag = diag::err_undeclared_var_use_suggest;
858 unsigned QualifiedDiag = diag::err_no_member_suggest;
860 NamedDecl *FirstDecl = Corrected.getFoundDecl();
861 NamedDecl *UnderlyingFirstDecl = Corrected.getCorrectionDecl();
862 if (getLangOpts().CPlusPlus && NextToken.is(tok::less) &&
863 UnderlyingFirstDecl && isa<TemplateDecl>(UnderlyingFirstDecl)) {
864 UnqualifiedDiag = diag::err_no_template_suggest;
865 QualifiedDiag = diag::err_no_member_template_suggest;
866 } else if (UnderlyingFirstDecl &&
867 (isa<TypeDecl>(UnderlyingFirstDecl) ||
868 isa<ObjCInterfaceDecl>(UnderlyingFirstDecl) ||
869 isa<ObjCCompatibleAliasDecl>(UnderlyingFirstDecl))) {
870 UnqualifiedDiag = diag::err_unknown_typename_suggest;
871 QualifiedDiag = diag::err_unknown_nested_typename_suggest;
875 diagnoseTypo(Corrected, PDiag(UnqualifiedDiag) << Name);
876 } else {// FIXME: is this even reachable? Test it.
877 std::string CorrectedStr(Corrected.getAsString(getLangOpts()));
878 bool DroppedSpecifier = Corrected.WillReplaceSpecifier() &&
879 Name->getName().equals(CorrectedStr);
880 diagnoseTypo(Corrected, PDiag(QualifiedDiag)
881 << Name << computeDeclContext(SS, false)
882 << DroppedSpecifier << SS.getRange());
885 // Update the name, so that the caller has the new name.
886 Name = Corrected.getCorrectionAsIdentifierInfo();
888 // Typo correction corrected to a keyword.
889 if (Corrected.isKeyword())
892 // Also update the LookupResult...
893 // FIXME: This should probably go away at some point
895 Result.setLookupName(Corrected.getCorrection());
897 Result.addDecl(FirstDecl);
899 // If we found an Objective-C instance variable, let
900 // LookupInObjCMethod build the appropriate expression to
901 // reference the ivar.
902 // FIXME: This is a gross hack.
903 if (ObjCIvarDecl *Ivar = Result.getAsSingle<ObjCIvarDecl>()) {
905 ExprResult E(LookupInObjCMethod(Result, S, Ivar->getIdentifier()));
913 // We failed to correct; just fall through and let the parser deal with it.
914 Result.suppressDiagnostics();
915 return NameClassification::Unknown();
917 case LookupResult::NotFoundInCurrentInstantiation: {
918 // We performed name lookup into the current instantiation, and there were
919 // dependent bases, so we treat this result the same way as any other
920 // dependent nested-name-specifier.
923 // A name used in a template declaration or definition and that is
924 // dependent on a template-parameter is assumed not to name a type
925 // unless the applicable name lookup finds a type name or the name is
926 // qualified by the keyword typename.
928 // FIXME: If the next token is '<', we might want to ask the parser to
929 // perform some heroics to see if we actually have a
930 // template-argument-list, which would indicate a missing 'template'
932 return ActOnDependentIdExpression(SS, /*TemplateKWLoc=*/SourceLocation(),
933 NameInfo, IsAddressOfOperand,
934 /*TemplateArgs=*/nullptr);
937 case LookupResult::Found:
938 case LookupResult::FoundOverloaded:
939 case LookupResult::FoundUnresolvedValue:
942 case LookupResult::Ambiguous:
943 if (getLangOpts().CPlusPlus && NextToken.is(tok::less) &&
944 hasAnyAcceptableTemplateNames(Result)) {
945 // C++ [temp.local]p3:
946 // A lookup that finds an injected-class-name (10.2) can result in an
947 // ambiguity in certain cases (for example, if it is found in more than
948 // one base class). If all of the injected-class-names that are found
949 // refer to specializations of the same class template, and if the name
950 // is followed by a template-argument-list, the reference refers to the
951 // class template itself and not a specialization thereof, and is not
954 // This filtering can make an ambiguous result into an unambiguous one,
955 // so try again after filtering out template names.
956 FilterAcceptableTemplateNames(Result);
957 if (!Result.isAmbiguous()) {
958 IsFilteredTemplateName = true;
963 // Diagnose the ambiguity and return an error.
964 return NameClassification::Error();
967 if (getLangOpts().CPlusPlus && NextToken.is(tok::less) &&
968 (IsFilteredTemplateName || hasAnyAcceptableTemplateNames(Result))) {
969 // C++ [temp.names]p3:
970 // After name lookup (3.4) finds that a name is a template-name or that
971 // an operator-function-id or a literal- operator-id refers to a set of
972 // overloaded functions any member of which is a function template if
973 // this is followed by a <, the < is always taken as the delimiter of a
974 // template-argument-list and never as the less-than operator.
975 if (!IsFilteredTemplateName)
976 FilterAcceptableTemplateNames(Result);
978 if (!Result.empty()) {
979 bool IsFunctionTemplate;
981 TemplateName Template;
982 if (Result.end() - Result.begin() > 1) {
983 IsFunctionTemplate = true;
984 Template = Context.getOverloadedTemplateName(Result.begin(),
988 = cast<TemplateDecl>((*Result.begin())->getUnderlyingDecl());
989 IsFunctionTemplate = isa<FunctionTemplateDecl>(TD);
990 IsVarTemplate = isa<VarTemplateDecl>(TD);
992 if (SS.isSet() && !SS.isInvalid())
993 Template = Context.getQualifiedTemplateName(SS.getScopeRep(),
994 /*TemplateKeyword=*/false,
997 Template = TemplateName(TD);
1000 if (IsFunctionTemplate) {
1001 // Function templates always go through overload resolution, at which
1002 // point we'll perform the various checks (e.g., accessibility) we need
1003 // to based on which function we selected.
1004 Result.suppressDiagnostics();
1006 return NameClassification::FunctionTemplate(Template);
1009 return IsVarTemplate ? NameClassification::VarTemplate(Template)
1010 : NameClassification::TypeTemplate(Template);
1014 NamedDecl *FirstDecl = (*Result.begin())->getUnderlyingDecl();
1015 if (TypeDecl *Type = dyn_cast<TypeDecl>(FirstDecl)) {
1016 DiagnoseUseOfDecl(Type, NameLoc);
1017 MarkAnyDeclReferenced(Type->getLocation(), Type, /*OdrUse=*/false);
1018 QualType T = Context.getTypeDeclType(Type);
1019 if (SS.isNotEmpty())
1020 return buildNestedType(*this, SS, T, NameLoc);
1021 return ParsedType::make(T);
1024 ObjCInterfaceDecl *Class = dyn_cast<ObjCInterfaceDecl>(FirstDecl);
1026 // FIXME: It's unfortunate that we don't have a Type node for handling this.
1027 if (ObjCCompatibleAliasDecl *Alias =
1028 dyn_cast<ObjCCompatibleAliasDecl>(FirstDecl))
1029 Class = Alias->getClassInterface();
1033 DiagnoseUseOfDecl(Class, NameLoc);
1035 if (NextToken.is(tok::period)) {
1036 // Interface. <something> is parsed as a property reference expression.
1037 // Just return "unknown" as a fall-through for now.
1038 Result.suppressDiagnostics();
1039 return NameClassification::Unknown();
1042 QualType T = Context.getObjCInterfaceType(Class);
1043 return ParsedType::make(T);
1046 // We can have a type template here if we're classifying a template argument.
1047 if (isa<TemplateDecl>(FirstDecl) && !isa<FunctionTemplateDecl>(FirstDecl))
1048 return NameClassification::TypeTemplate(
1049 TemplateName(cast<TemplateDecl>(FirstDecl)));
1051 // Check for a tag type hidden by a non-type decl in a few cases where it
1052 // seems likely a type is wanted instead of the non-type that was found.
1053 bool NextIsOp = NextToken.isOneOf(tok::amp, tok::star);
1054 if ((NextToken.is(tok::identifier) ||
1056 FirstDecl->getUnderlyingDecl()->isFunctionOrFunctionTemplate())) &&
1057 isTagTypeWithMissingTag(*this, Result, S, SS, Name, NameLoc)) {
1058 TypeDecl *Type = Result.getAsSingle<TypeDecl>();
1059 DiagnoseUseOfDecl(Type, NameLoc);
1060 QualType T = Context.getTypeDeclType(Type);
1061 if (SS.isNotEmpty())
1062 return buildNestedType(*this, SS, T, NameLoc);
1063 return ParsedType::make(T);
1066 if (FirstDecl->isCXXClassMember())
1067 return BuildPossibleImplicitMemberExpr(SS, SourceLocation(), Result,
1070 bool ADL = UseArgumentDependentLookup(SS, Result, NextToken.is(tok::l_paren));
1071 return BuildDeclarationNameExpr(SS, Result, ADL);
1074 // Determines the context to return to after temporarily entering a
1075 // context. This depends in an unnecessarily complicated way on the
1076 // exact ordering of callbacks from the parser.
1077 DeclContext *Sema::getContainingDC(DeclContext *DC) {
1079 // Functions defined inline within classes aren't parsed until we've
1080 // finished parsing the top-level class, so the top-level class is
1081 // the context we'll need to return to.
1082 // A Lambda call operator whose parent is a class must not be treated
1083 // as an inline member function. A Lambda can be used legally
1084 // either as an in-class member initializer or a default argument. These
1085 // are parsed once the class has been marked complete and so the containing
1086 // context would be the nested class (when the lambda is defined in one);
1087 // If the class is not complete, then the lambda is being used in an
1088 // ill-formed fashion (such as to specify the width of a bit-field, or
1089 // in an array-bound) - in which case we still want to return the
1090 // lexically containing DC (which could be a nested class).
1091 if (isa<FunctionDecl>(DC) && !isLambdaCallOperator(DC)) {
1092 DC = DC->getLexicalParent();
1094 // A function not defined within a class will always return to its
1096 if (!isa<CXXRecordDecl>(DC))
1099 // A C++ inline method/friend is parsed *after* the topmost class
1100 // it was declared in is fully parsed ("complete"); the topmost
1101 // class is the context we need to return to.
1102 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent()))
1105 // Return the declaration context of the topmost class the inline method is
1110 return DC->getLexicalParent();
1113 void Sema::PushDeclContext(Scope *S, DeclContext *DC) {
1114 assert(getContainingDC(DC) == CurContext &&
1115 "The next DeclContext should be lexically contained in the current one.");
1120 void Sema::PopDeclContext() {
1121 assert(CurContext && "DeclContext imbalance!");
1123 CurContext = getContainingDC(CurContext);
1124 assert(CurContext && "Popped translation unit!");
1127 Sema::SkippedDefinitionContext Sema::ActOnTagStartSkippedDefinition(Scope *S,
1129 // Unlike PushDeclContext, the context to which we return is not necessarily
1130 // the containing DC of TD, because the new context will be some pre-existing
1131 // TagDecl definition instead of a fresh one.
1132 auto Result = static_cast<SkippedDefinitionContext>(CurContext);
1133 CurContext = cast<TagDecl>(D)->getDefinition();
1134 assert(CurContext && "skipping definition of undefined tag");
1135 // Start lookups from the parent of the current context; we don't want to look
1136 // into the pre-existing complete definition.
1137 S->setEntity(CurContext->getLookupParent());
1141 void Sema::ActOnTagFinishSkippedDefinition(SkippedDefinitionContext Context) {
1142 CurContext = static_cast<decltype(CurContext)>(Context);
1145 /// EnterDeclaratorContext - Used when we must lookup names in the context
1146 /// of a declarator's nested name specifier.
1148 void Sema::EnterDeclaratorContext(Scope *S, DeclContext *DC) {
1149 // C++0x [basic.lookup.unqual]p13:
1150 // A name used in the definition of a static data member of class
1151 // X (after the qualified-id of the static member) is looked up as
1152 // if the name was used in a member function of X.
1153 // C++0x [basic.lookup.unqual]p14:
1154 // If a variable member of a namespace is defined outside of the
1155 // scope of its namespace then any name used in the definition of
1156 // the variable member (after the declarator-id) is looked up as
1157 // if the definition of the variable member occurred in its
1159 // Both of these imply that we should push a scope whose context
1160 // is the semantic context of the declaration. We can't use
1161 // PushDeclContext here because that context is not necessarily
1162 // lexically contained in the current context. Fortunately,
1163 // the containing scope should have the appropriate information.
1165 assert(!S->getEntity() && "scope already has entity");
1168 Scope *Ancestor = S->getParent();
1169 while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent();
1170 assert(Ancestor->getEntity() == CurContext && "ancestor context mismatch");
1177 void Sema::ExitDeclaratorContext(Scope *S) {
1178 assert(S->getEntity() == CurContext && "Context imbalance!");
1180 // Switch back to the lexical context. The safety of this is
1181 // enforced by an assert in EnterDeclaratorContext.
1182 Scope *Ancestor = S->getParent();
1183 while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent();
1184 CurContext = Ancestor->getEntity();
1186 // We don't need to do anything with the scope, which is going to
1190 void Sema::ActOnReenterFunctionContext(Scope* S, Decl *D) {
1191 // We assume that the caller has already called
1192 // ActOnReenterTemplateScope so getTemplatedDecl() works.
1193 FunctionDecl *FD = D->getAsFunction();
1197 // Same implementation as PushDeclContext, but enters the context
1198 // from the lexical parent, rather than the top-level class.
1199 assert(CurContext == FD->getLexicalParent() &&
1200 "The next DeclContext should be lexically contained in the current one.");
1202 S->setEntity(CurContext);
1204 for (unsigned P = 0, NumParams = FD->getNumParams(); P < NumParams; ++P) {
1205 ParmVarDecl *Param = FD->getParamDecl(P);
1206 // If the parameter has an identifier, then add it to the scope
1207 if (Param->getIdentifier()) {
1209 IdResolver.AddDecl(Param);
1214 void Sema::ActOnExitFunctionContext() {
1215 // Same implementation as PopDeclContext, but returns to the lexical parent,
1216 // rather than the top-level class.
1217 assert(CurContext && "DeclContext imbalance!");
1218 CurContext = CurContext->getLexicalParent();
1219 assert(CurContext && "Popped translation unit!");
1222 /// \brief Determine whether we allow overloading of the function
1223 /// PrevDecl with another declaration.
1225 /// This routine determines whether overloading is possible, not
1226 /// whether some new function is actually an overload. It will return
1227 /// true in C++ (where we can always provide overloads) or, as an
1228 /// extension, in C when the previous function is already an
1229 /// overloaded function declaration or has the "overloadable"
1231 static bool AllowOverloadingOfFunction(LookupResult &Previous,
1232 ASTContext &Context) {
1233 if (Context.getLangOpts().CPlusPlus)
1236 if (Previous.getResultKind() == LookupResult::FoundOverloaded)
1239 return (Previous.getResultKind() == LookupResult::Found
1240 && Previous.getFoundDecl()->hasAttr<OverloadableAttr>());
1243 /// Add this decl to the scope shadowed decl chains.
1244 void Sema::PushOnScopeChains(NamedDecl *D, Scope *S, bool AddToContext) {
1245 // Move up the scope chain until we find the nearest enclosing
1246 // non-transparent context. The declaration will be introduced into this
1248 while (S->getEntity() && S->getEntity()->isTransparentContext())
1251 // Add scoped declarations into their context, so that they can be
1252 // found later. Declarations without a context won't be inserted
1253 // into any context.
1255 CurContext->addDecl(D);
1257 // Out-of-line definitions shouldn't be pushed into scope in C++, unless they
1258 // are function-local declarations.
1259 if (getLangOpts().CPlusPlus && D->isOutOfLine() &&
1260 !D->getDeclContext()->getRedeclContext()->Equals(
1261 D->getLexicalDeclContext()->getRedeclContext()) &&
1262 !D->getLexicalDeclContext()->isFunctionOrMethod())
1265 // Template instantiations should also not be pushed into scope.
1266 if (isa<FunctionDecl>(D) &&
1267 cast<FunctionDecl>(D)->isFunctionTemplateSpecialization())
1270 // If this replaces anything in the current scope,
1271 IdentifierResolver::iterator I = IdResolver.begin(D->getDeclName()),
1272 IEnd = IdResolver.end();
1273 for (; I != IEnd; ++I) {
1274 if (S->isDeclScope(*I) && D->declarationReplaces(*I)) {
1276 IdResolver.RemoveDecl(*I);
1278 // Should only need to replace one decl.
1285 if (isa<LabelDecl>(D) && !cast<LabelDecl>(D)->isGnuLocal()) {
1286 // Implicitly-generated labels may end up getting generated in an order that
1287 // isn't strictly lexical, which breaks name lookup. Be careful to insert
1288 // the label at the appropriate place in the identifier chain.
1289 for (I = IdResolver.begin(D->getDeclName()); I != IEnd; ++I) {
1290 DeclContext *IDC = (*I)->getLexicalDeclContext()->getRedeclContext();
1291 if (IDC == CurContext) {
1292 if (!S->isDeclScope(*I))
1294 } else if (IDC->Encloses(CurContext))
1298 IdResolver.InsertDeclAfter(I, D);
1300 IdResolver.AddDecl(D);
1304 void Sema::pushExternalDeclIntoScope(NamedDecl *D, DeclarationName Name) {
1305 if (IdResolver.tryAddTopLevelDecl(D, Name) && TUScope)
1306 TUScope->AddDecl(D);
1309 bool Sema::isDeclInScope(NamedDecl *D, DeclContext *Ctx, Scope *S,
1310 bool AllowInlineNamespace) {
1311 return IdResolver.isDeclInScope(D, Ctx, S, AllowInlineNamespace);
1314 Scope *Sema::getScopeForDeclContext(Scope *S, DeclContext *DC) {
1315 DeclContext *TargetDC = DC->getPrimaryContext();
1317 if (DeclContext *ScopeDC = S->getEntity())
1318 if (ScopeDC->getPrimaryContext() == TargetDC)
1320 } while ((S = S->getParent()));
1325 static bool isOutOfScopePreviousDeclaration(NamedDecl *,
1329 /// Filters out lookup results that don't fall within the given scope
1330 /// as determined by isDeclInScope.
1331 void Sema::FilterLookupForScope(LookupResult &R, DeclContext *Ctx, Scope *S,
1332 bool ConsiderLinkage,
1333 bool AllowInlineNamespace) {
1334 LookupResult::Filter F = R.makeFilter();
1335 while (F.hasNext()) {
1336 NamedDecl *D = F.next();
1338 if (isDeclInScope(D, Ctx, S, AllowInlineNamespace))
1341 if (ConsiderLinkage && isOutOfScopePreviousDeclaration(D, Ctx, Context))
1350 static bool isUsingDecl(NamedDecl *D) {
1351 return isa<UsingShadowDecl>(D) ||
1352 isa<UnresolvedUsingTypenameDecl>(D) ||
1353 isa<UnresolvedUsingValueDecl>(D);
1356 /// Removes using shadow declarations from the lookup results.
1357 static void RemoveUsingDecls(LookupResult &R) {
1358 LookupResult::Filter F = R.makeFilter();
1360 if (isUsingDecl(F.next()))
1366 /// \brief Check for this common pattern:
1369 /// S(const S&); // DO NOT IMPLEMENT
1370 /// void operator=(const S&); // DO NOT IMPLEMENT
1373 static bool IsDisallowedCopyOrAssign(const CXXMethodDecl *D) {
1374 // FIXME: Should check for private access too but access is set after we get
1376 if (D->doesThisDeclarationHaveABody())
1379 if (const CXXConstructorDecl *CD = dyn_cast<CXXConstructorDecl>(D))
1380 return CD->isCopyConstructor();
1381 if (const CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(D))
1382 return Method->isCopyAssignmentOperator();
1386 // We need this to handle
1389 // void *foo() { return 0; }
1392 // When we see foo we don't know if after the typedef we will get 'A' or '*A'
1393 // for example. If 'A', foo will have external linkage. If we have '*A',
1394 // foo will have no linkage. Since we can't know until we get to the end
1395 // of the typedef, this function finds out if D might have non-external linkage.
1396 // Callers should verify at the end of the TU if it D has external linkage or
1398 bool Sema::mightHaveNonExternalLinkage(const DeclaratorDecl *D) {
1399 const DeclContext *DC = D->getDeclContext();
1400 while (!DC->isTranslationUnit()) {
1401 if (const RecordDecl *RD = dyn_cast<RecordDecl>(DC)){
1402 if (!RD->hasNameForLinkage())
1405 DC = DC->getParent();
1408 return !D->isExternallyVisible();
1411 // FIXME: This needs to be refactored; some other isInMainFile users want
1413 static bool isMainFileLoc(const Sema &S, SourceLocation Loc) {
1414 if (S.TUKind != TU_Complete)
1416 return S.SourceMgr.isInMainFile(Loc);
1419 bool Sema::ShouldWarnIfUnusedFileScopedDecl(const DeclaratorDecl *D) const {
1422 if (D->isInvalidDecl() || D->isUsed() || D->hasAttr<UnusedAttr>())
1425 // Ignore all entities declared within templates, and out-of-line definitions
1426 // of members of class templates.
1427 if (D->getDeclContext()->isDependentContext() ||
1428 D->getLexicalDeclContext()->isDependentContext())
1431 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
1432 if (FD->getTemplateSpecializationKind() == TSK_ImplicitInstantiation)
1435 if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) {
1436 if (MD->isVirtual() || IsDisallowedCopyOrAssign(MD))
1439 // 'static inline' functions are defined in headers; don't warn.
1440 if (FD->isInlined() && !isMainFileLoc(*this, FD->getLocation()))
1444 if (FD->doesThisDeclarationHaveABody() &&
1445 Context.DeclMustBeEmitted(FD))
1447 } else if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
1448 // Constants and utility variables are defined in headers with internal
1449 // linkage; don't warn. (Unlike functions, there isn't a convenient marker
1451 if (!isMainFileLoc(*this, VD->getLocation()))
1454 if (Context.DeclMustBeEmitted(VD))
1457 if (VD->isStaticDataMember() &&
1458 VD->getTemplateSpecializationKind() == TSK_ImplicitInstantiation)
1461 if (VD->isInline() && !isMainFileLoc(*this, VD->getLocation()))
1467 // Only warn for unused decls internal to the translation unit.
1468 // FIXME: This seems like a bogus check; it suppresses -Wunused-function
1469 // for inline functions defined in the main source file, for instance.
1470 return mightHaveNonExternalLinkage(D);
1473 void Sema::MarkUnusedFileScopedDecl(const DeclaratorDecl *D) {
1477 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
1478 const FunctionDecl *First = FD->getFirstDecl();
1479 if (FD != First && ShouldWarnIfUnusedFileScopedDecl(First))
1480 return; // First should already be in the vector.
1483 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
1484 const VarDecl *First = VD->getFirstDecl();
1485 if (VD != First && ShouldWarnIfUnusedFileScopedDecl(First))
1486 return; // First should already be in the vector.
1489 if (ShouldWarnIfUnusedFileScopedDecl(D))
1490 UnusedFileScopedDecls.push_back(D);
1493 static bool ShouldDiagnoseUnusedDecl(const NamedDecl *D) {
1494 if (D->isInvalidDecl())
1497 if (D->isReferenced() || D->isUsed() || D->hasAttr<UnusedAttr>() ||
1498 D->hasAttr<ObjCPreciseLifetimeAttr>())
1501 if (isa<LabelDecl>(D))
1504 // Except for labels, we only care about unused decls that are local to
1506 bool WithinFunction = D->getDeclContext()->isFunctionOrMethod();
1507 if (const auto *R = dyn_cast<CXXRecordDecl>(D->getDeclContext()))
1508 // For dependent types, the diagnostic is deferred.
1510 WithinFunction || (R->isLocalClass() && !R->isDependentType());
1511 if (!WithinFunction)
1514 if (isa<TypedefNameDecl>(D))
1517 // White-list anything that isn't a local variable.
1518 if (!isa<VarDecl>(D) || isa<ParmVarDecl>(D) || isa<ImplicitParamDecl>(D))
1521 // Types of valid local variables should be complete, so this should succeed.
1522 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
1524 // White-list anything with an __attribute__((unused)) type.
1525 QualType Ty = VD->getType();
1527 // Only look at the outermost level of typedef.
1528 if (const TypedefType *TT = Ty->getAs<TypedefType>()) {
1529 if (TT->getDecl()->hasAttr<UnusedAttr>())
1533 // If we failed to complete the type for some reason, or if the type is
1534 // dependent, don't diagnose the variable.
1535 if (Ty->isIncompleteType() || Ty->isDependentType())
1538 if (const TagType *TT = Ty->getAs<TagType>()) {
1539 const TagDecl *Tag = TT->getDecl();
1540 if (Tag->hasAttr<UnusedAttr>())
1543 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(Tag)) {
1544 if (!RD->hasTrivialDestructor() && !RD->hasAttr<WarnUnusedAttr>())
1547 if (const Expr *Init = VD->getInit()) {
1548 if (const ExprWithCleanups *Cleanups =
1549 dyn_cast<ExprWithCleanups>(Init))
1550 Init = Cleanups->getSubExpr();
1551 const CXXConstructExpr *Construct =
1552 dyn_cast<CXXConstructExpr>(Init);
1553 if (Construct && !Construct->isElidable()) {
1554 CXXConstructorDecl *CD = Construct->getConstructor();
1555 if (!CD->isTrivial() && !RD->hasAttr<WarnUnusedAttr>())
1562 // TODO: __attribute__((unused)) templates?
1568 static void GenerateFixForUnusedDecl(const NamedDecl *D, ASTContext &Ctx,
1570 if (isa<LabelDecl>(D)) {
1571 SourceLocation AfterColon = Lexer::findLocationAfterToken(D->getLocEnd(),
1572 tok::colon, Ctx.getSourceManager(), Ctx.getLangOpts(), true);
1573 if (AfterColon.isInvalid())
1575 Hint = FixItHint::CreateRemoval(CharSourceRange::
1576 getCharRange(D->getLocStart(), AfterColon));
1580 void Sema::DiagnoseUnusedNestedTypedefs(const RecordDecl *D) {
1581 if (D->getTypeForDecl()->isDependentType())
1584 for (auto *TmpD : D->decls()) {
1585 if (const auto *T = dyn_cast<TypedefNameDecl>(TmpD))
1586 DiagnoseUnusedDecl(T);
1587 else if(const auto *R = dyn_cast<RecordDecl>(TmpD))
1588 DiagnoseUnusedNestedTypedefs(R);
1592 /// DiagnoseUnusedDecl - Emit warnings about declarations that are not used
1593 /// unless they are marked attr(unused).
1594 void Sema::DiagnoseUnusedDecl(const NamedDecl *D) {
1595 if (!ShouldDiagnoseUnusedDecl(D))
1598 if (auto *TD = dyn_cast<TypedefNameDecl>(D)) {
1599 // typedefs can be referenced later on, so the diagnostics are emitted
1600 // at end-of-translation-unit.
1601 UnusedLocalTypedefNameCandidates.insert(TD);
1606 GenerateFixForUnusedDecl(D, Context, Hint);
1609 if (isa<VarDecl>(D) && cast<VarDecl>(D)->isExceptionVariable())
1610 DiagID = diag::warn_unused_exception_param;
1611 else if (isa<LabelDecl>(D))
1612 DiagID = diag::warn_unused_label;
1614 DiagID = diag::warn_unused_variable;
1616 Diag(D->getLocation(), DiagID) << D->getDeclName() << Hint;
1619 static void CheckPoppedLabel(LabelDecl *L, Sema &S) {
1620 // Verify that we have no forward references left. If so, there was a goto
1621 // or address of a label taken, but no definition of it. Label fwd
1622 // definitions are indicated with a null substmt which is also not a resolved
1623 // MS inline assembly label name.
1624 bool Diagnose = false;
1625 if (L->isMSAsmLabel())
1626 Diagnose = !L->isResolvedMSAsmLabel();
1628 Diagnose = L->getStmt() == nullptr;
1630 S.Diag(L->getLocation(), diag::err_undeclared_label_use) <<L->getDeclName();
1633 void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) {
1634 S->mergeNRVOIntoParent();
1636 if (S->decl_empty()) return;
1637 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) &&
1638 "Scope shouldn't contain decls!");
1640 for (auto *TmpD : S->decls()) {
1641 assert(TmpD && "This decl didn't get pushed??");
1643 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?");
1644 NamedDecl *D = cast<NamedDecl>(TmpD);
1646 if (!D->getDeclName()) continue;
1648 // Diagnose unused variables in this scope.
1649 if (!S->hasUnrecoverableErrorOccurred()) {
1650 DiagnoseUnusedDecl(D);
1651 if (const auto *RD = dyn_cast<RecordDecl>(D))
1652 DiagnoseUnusedNestedTypedefs(RD);
1655 // If this was a forward reference to a label, verify it was defined.
1656 if (LabelDecl *LD = dyn_cast<LabelDecl>(D))
1657 CheckPoppedLabel(LD, *this);
1659 // Remove this name from our lexical scope, and warn on it if we haven't
1661 IdResolver.RemoveDecl(D);
1662 auto ShadowI = ShadowingDecls.find(D);
1663 if (ShadowI != ShadowingDecls.end()) {
1664 if (const auto *FD = dyn_cast<FieldDecl>(ShadowI->second)) {
1665 Diag(D->getLocation(), diag::warn_ctor_parm_shadows_field)
1666 << D << FD << FD->getParent();
1667 Diag(FD->getLocation(), diag::note_previous_declaration);
1669 ShadowingDecls.erase(ShadowI);
1674 /// \brief Look for an Objective-C class in the translation unit.
1676 /// \param Id The name of the Objective-C class we're looking for. If
1677 /// typo-correction fixes this name, the Id will be updated
1678 /// to the fixed name.
1680 /// \param IdLoc The location of the name in the translation unit.
1682 /// \param DoTypoCorrection If true, this routine will attempt typo correction
1683 /// if there is no class with the given name.
1685 /// \returns The declaration of the named Objective-C class, or NULL if the
1686 /// class could not be found.
1687 ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *&Id,
1688 SourceLocation IdLoc,
1689 bool DoTypoCorrection) {
1690 // The third "scope" argument is 0 since we aren't enabling lazy built-in
1691 // creation from this context.
1692 NamedDecl *IDecl = LookupSingleName(TUScope, Id, IdLoc, LookupOrdinaryName);
1694 if (!IDecl && DoTypoCorrection) {
1695 // Perform typo correction at the given location, but only if we
1696 // find an Objective-C class name.
1697 if (TypoCorrection C = CorrectTypo(
1698 DeclarationNameInfo(Id, IdLoc), LookupOrdinaryName, TUScope, nullptr,
1699 llvm::make_unique<DeclFilterCCC<ObjCInterfaceDecl>>(),
1700 CTK_ErrorRecovery)) {
1701 diagnoseTypo(C, PDiag(diag::err_undef_interface_suggest) << Id);
1702 IDecl = C.getCorrectionDeclAs<ObjCInterfaceDecl>();
1703 Id = IDecl->getIdentifier();
1706 ObjCInterfaceDecl *Def = dyn_cast_or_null<ObjCInterfaceDecl>(IDecl);
1707 // This routine must always return a class definition, if any.
1708 if (Def && Def->getDefinition())
1709 Def = Def->getDefinition();
1713 /// getNonFieldDeclScope - Retrieves the innermost scope, starting
1714 /// from S, where a non-field would be declared. This routine copes
1715 /// with the difference between C and C++ scoping rules in structs and
1716 /// unions. For example, the following code is well-formed in C but
1717 /// ill-formed in C++:
1723 /// void test_S6() {
1728 /// For the declaration of BAR, this routine will return a different
1729 /// scope. The scope S will be the scope of the unnamed enumeration
1730 /// within S6. In C++, this routine will return the scope associated
1731 /// with S6, because the enumeration's scope is a transparent
1732 /// context but structures can contain non-field names. In C, this
1733 /// routine will return the translation unit scope, since the
1734 /// enumeration's scope is a transparent context and structures cannot
1735 /// contain non-field names.
1736 Scope *Sema::getNonFieldDeclScope(Scope *S) {
1737 while (((S->getFlags() & Scope::DeclScope) == 0) ||
1738 (S->getEntity() && S->getEntity()->isTransparentContext()) ||
1739 (S->isClassScope() && !getLangOpts().CPlusPlus))
1744 /// \brief Looks up the declaration of "struct objc_super" and
1745 /// saves it for later use in building builtin declaration of
1746 /// objc_msgSendSuper and objc_msgSendSuper_stret. If no such
1747 /// pre-existing declaration exists no action takes place.
1748 static void LookupPredefedObjCSuperType(Sema &ThisSema, Scope *S,
1749 IdentifierInfo *II) {
1750 if (!II->isStr("objc_msgSendSuper"))
1752 ASTContext &Context = ThisSema.Context;
1754 LookupResult Result(ThisSema, &Context.Idents.get("objc_super"),
1755 SourceLocation(), Sema::LookupTagName);
1756 ThisSema.LookupName(Result, S);
1757 if (Result.getResultKind() == LookupResult::Found)
1758 if (const TagDecl *TD = Result.getAsSingle<TagDecl>())
1759 Context.setObjCSuperType(Context.getTagDeclType(TD));
1762 static StringRef getHeaderName(ASTContext::GetBuiltinTypeError Error) {
1764 case ASTContext::GE_None:
1766 case ASTContext::GE_Missing_stdio:
1768 case ASTContext::GE_Missing_setjmp:
1770 case ASTContext::GE_Missing_ucontext:
1771 return "ucontext.h";
1773 llvm_unreachable("unhandled error kind");
1776 /// LazilyCreateBuiltin - The specified Builtin-ID was first used at
1777 /// file scope. lazily create a decl for it. ForRedeclaration is true
1778 /// if we're creating this built-in in anticipation of redeclaring the
1780 NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned ID,
1781 Scope *S, bool ForRedeclaration,
1782 SourceLocation Loc) {
1783 LookupPredefedObjCSuperType(*this, S, II);
1785 ASTContext::GetBuiltinTypeError Error;
1786 QualType R = Context.GetBuiltinType(ID, Error);
1788 if (ForRedeclaration)
1789 Diag(Loc, diag::warn_implicit_decl_requires_sysheader)
1790 << getHeaderName(Error) << Context.BuiltinInfo.getName(ID);
1794 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(ID)) {
1795 Diag(Loc, diag::ext_implicit_lib_function_decl)
1796 << Context.BuiltinInfo.getName(ID) << R;
1797 if (Context.BuiltinInfo.getHeaderName(ID) &&
1798 !Diags.isIgnored(diag::ext_implicit_lib_function_decl, Loc))
1799 Diag(Loc, diag::note_include_header_or_declare)
1800 << Context.BuiltinInfo.getHeaderName(ID)
1801 << Context.BuiltinInfo.getName(ID);
1807 DeclContext *Parent = Context.getTranslationUnitDecl();
1808 if (getLangOpts().CPlusPlus) {
1809 LinkageSpecDecl *CLinkageDecl =
1810 LinkageSpecDecl::Create(Context, Parent, Loc, Loc,
1811 LinkageSpecDecl::lang_c, false);
1812 CLinkageDecl->setImplicit();
1813 Parent->addDecl(CLinkageDecl);
1814 Parent = CLinkageDecl;
1817 FunctionDecl *New = FunctionDecl::Create(Context,
1819 Loc, Loc, II, R, /*TInfo=*/nullptr,
1822 R->isFunctionProtoType());
1825 // Create Decl objects for each parameter, adding them to the
1827 if (const FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) {
1828 SmallVector<ParmVarDecl*, 16> Params;
1829 for (unsigned i = 0, e = FT->getNumParams(); i != e; ++i) {
1831 ParmVarDecl::Create(Context, New, SourceLocation(), SourceLocation(),
1832 nullptr, FT->getParamType(i), /*TInfo=*/nullptr,
1834 parm->setScopeInfo(0, i);
1835 Params.push_back(parm);
1837 New->setParams(Params);
1840 AddKnownFunctionAttributes(New);
1841 RegisterLocallyScopedExternCDecl(New, S);
1843 // TUScope is the translation-unit scope to insert this function into.
1844 // FIXME: This is hideous. We need to teach PushOnScopeChains to
1845 // relate Scopes to DeclContexts, and probably eliminate CurContext
1846 // entirely, but we're not there yet.
1847 DeclContext *SavedContext = CurContext;
1848 CurContext = Parent;
1849 PushOnScopeChains(New, TUScope);
1850 CurContext = SavedContext;
1854 /// Typedef declarations don't have linkage, but they still denote the same
1855 /// entity if their types are the same.
1856 /// FIXME: This is notionally doing the same thing as ASTReaderDecl's
1858 static void filterNonConflictingPreviousTypedefDecls(Sema &S,
1859 TypedefNameDecl *Decl,
1860 LookupResult &Previous) {
1861 // This is only interesting when modules are enabled.
1862 if (!S.getLangOpts().Modules && !S.getLangOpts().ModulesLocalVisibility)
1865 // Empty sets are uninteresting.
1866 if (Previous.empty())
1869 LookupResult::Filter Filter = Previous.makeFilter();
1870 while (Filter.hasNext()) {
1871 NamedDecl *Old = Filter.next();
1873 // Non-hidden declarations are never ignored.
1874 if (S.isVisible(Old))
1877 // Declarations of the same entity are not ignored, even if they have
1878 // different linkages.
1879 if (auto *OldTD = dyn_cast<TypedefNameDecl>(Old)) {
1880 if (S.Context.hasSameType(OldTD->getUnderlyingType(),
1881 Decl->getUnderlyingType()))
1884 // If both declarations give a tag declaration a typedef name for linkage
1885 // purposes, then they declare the same entity.
1886 if (S.getLangOpts().CPlusPlus &&
1887 OldTD->getAnonDeclWithTypedefName(/*AnyRedecl*/true) &&
1888 Decl->getAnonDeclWithTypedefName())
1898 bool Sema::isIncompatibleTypedef(TypeDecl *Old, TypedefNameDecl *New) {
1900 if (TypedefNameDecl *OldTypedef = dyn_cast<TypedefNameDecl>(Old))
1901 OldType = OldTypedef->getUnderlyingType();
1903 OldType = Context.getTypeDeclType(Old);
1904 QualType NewType = New->getUnderlyingType();
1906 if (NewType->isVariablyModifiedType()) {
1907 // Must not redefine a typedef with a variably-modified type.
1908 int Kind = isa<TypeAliasDecl>(Old) ? 1 : 0;
1909 Diag(New->getLocation(), diag::err_redefinition_variably_modified_typedef)
1911 if (Old->getLocation().isValid())
1912 Diag(Old->getLocation(), diag::note_previous_definition);
1913 New->setInvalidDecl();
1917 if (OldType != NewType &&
1918 !OldType->isDependentType() &&
1919 !NewType->isDependentType() &&
1920 !Context.hasSameType(OldType, NewType)) {
1921 int Kind = isa<TypeAliasDecl>(Old) ? 1 : 0;
1922 Diag(New->getLocation(), diag::err_redefinition_different_typedef)
1923 << Kind << NewType << OldType;
1924 if (Old->getLocation().isValid())
1925 Diag(Old->getLocation(), diag::note_previous_definition);
1926 New->setInvalidDecl();
1932 /// MergeTypedefNameDecl - We just parsed a typedef 'New' which has the
1933 /// same name and scope as a previous declaration 'Old'. Figure out
1934 /// how to resolve this situation, merging decls or emitting
1935 /// diagnostics as appropriate. If there was an error, set New to be invalid.
1937 void Sema::MergeTypedefNameDecl(Scope *S, TypedefNameDecl *New,
1938 LookupResult &OldDecls) {
1939 // If the new decl is known invalid already, don't bother doing any
1941 if (New->isInvalidDecl()) return;
1943 // Allow multiple definitions for ObjC built-in typedefs.
1944 // FIXME: Verify the underlying types are equivalent!
1945 if (getLangOpts().ObjC1) {
1946 const IdentifierInfo *TypeID = New->getIdentifier();
1947 switch (TypeID->getLength()) {
1951 if (!TypeID->isStr("id"))
1953 QualType T = New->getUnderlyingType();
1954 if (!T->isPointerType())
1956 if (!T->isVoidPointerType()) {
1957 QualType PT = T->getAs<PointerType>()->getPointeeType();
1958 if (!PT->isStructureType())
1961 Context.setObjCIdRedefinitionType(T);
1962 // Install the built-in type for 'id', ignoring the current definition.
1963 New->setTypeForDecl(Context.getObjCIdType().getTypePtr());
1967 if (!TypeID->isStr("Class"))
1969 Context.setObjCClassRedefinitionType(New->getUnderlyingType());
1970 // Install the built-in type for 'Class', ignoring the current definition.
1971 New->setTypeForDecl(Context.getObjCClassType().getTypePtr());
1974 if (!TypeID->isStr("SEL"))
1976 Context.setObjCSelRedefinitionType(New->getUnderlyingType());
1977 // Install the built-in type for 'SEL', ignoring the current definition.
1978 New->setTypeForDecl(Context.getObjCSelType().getTypePtr());
1981 // Fall through - the typedef name was not a builtin type.
1984 // Verify the old decl was also a type.
1985 TypeDecl *Old = OldDecls.getAsSingle<TypeDecl>();
1987 Diag(New->getLocation(), diag::err_redefinition_different_kind)
1988 << New->getDeclName();
1990 NamedDecl *OldD = OldDecls.getRepresentativeDecl();
1991 if (OldD->getLocation().isValid())
1992 Diag(OldD->getLocation(), diag::note_previous_definition);
1994 return New->setInvalidDecl();
1997 // If the old declaration is invalid, just give up here.
1998 if (Old->isInvalidDecl())
1999 return New->setInvalidDecl();
2001 if (auto *OldTD = dyn_cast<TypedefNameDecl>(Old)) {
2002 auto *OldTag = OldTD->getAnonDeclWithTypedefName(/*AnyRedecl*/true);
2003 auto *NewTag = New->getAnonDeclWithTypedefName();
2004 NamedDecl *Hidden = nullptr;
2005 if (getLangOpts().CPlusPlus && OldTag && NewTag &&
2006 OldTag->getCanonicalDecl() != NewTag->getCanonicalDecl() &&
2007 !hasVisibleDefinition(OldTag, &Hidden)) {
2008 // There is a definition of this tag, but it is not visible. Use it
2009 // instead of our tag.
2010 New->setTypeForDecl(OldTD->getTypeForDecl());
2011 if (OldTD->isModed())
2012 New->setModedTypeSourceInfo(OldTD->getTypeSourceInfo(),
2013 OldTD->getUnderlyingType());
2015 New->setTypeSourceInfo(OldTD->getTypeSourceInfo());
2017 // Make the old tag definition visible.
2018 makeMergedDefinitionVisible(Hidden, NewTag->getLocation());
2020 // If this was an unscoped enumeration, yank all of its enumerators
2021 // out of the scope.
2022 if (isa<EnumDecl>(NewTag)) {
2023 Scope *EnumScope = getNonFieldDeclScope(S);
2024 for (auto *D : NewTag->decls()) {
2025 auto *ED = cast<EnumConstantDecl>(D);
2026 assert(EnumScope->isDeclScope(ED));
2027 EnumScope->RemoveDecl(ED);
2028 IdResolver.RemoveDecl(ED);
2029 ED->getLexicalDeclContext()->removeDecl(ED);
2035 // If the typedef types are not identical, reject them in all languages and
2036 // with any extensions enabled.
2037 if (isIncompatibleTypedef(Old, New))
2040 // The types match. Link up the redeclaration chain and merge attributes if
2041 // the old declaration was a typedef.
2042 if (TypedefNameDecl *Typedef = dyn_cast<TypedefNameDecl>(Old)) {
2043 New->setPreviousDecl(Typedef);
2044 mergeDeclAttributes(New, Old);
2047 if (getLangOpts().MicrosoftExt)
2050 if (getLangOpts().CPlusPlus) {
2051 // C++ [dcl.typedef]p2:
2052 // In a given non-class scope, a typedef specifier can be used to
2053 // redefine the name of any type declared in that scope to refer
2054 // to the type to which it already refers.
2055 if (!isa<CXXRecordDecl>(CurContext))
2058 // C++0x [dcl.typedef]p4:
2059 // In a given class scope, a typedef specifier can be used to redefine
2060 // any class-name declared in that scope that is not also a typedef-name
2061 // to refer to the type to which it already refers.
2063 // This wording came in via DR424, which was a correction to the
2064 // wording in DR56, which accidentally banned code like:
2067 // typedef struct A { } A;
2070 // in the C++03 standard. We implement the C++0x semantics, which
2071 // allow the above but disallow
2078 // since that was the intent of DR56.
2079 if (!isa<TypedefNameDecl>(Old))
2082 Diag(New->getLocation(), diag::err_redefinition)
2083 << New->getDeclName();
2084 Diag(Old->getLocation(), diag::note_previous_definition);
2085 return New->setInvalidDecl();
2088 // Modules always permit redefinition of typedefs, as does C11.
2089 if (getLangOpts().Modules || getLangOpts().C11)
2092 // If we have a redefinition of a typedef in C, emit a warning. This warning
2093 // is normally mapped to an error, but can be controlled with
2094 // -Wtypedef-redefinition. If either the original or the redefinition is
2095 // in a system header, don't emit this for compatibility with GCC.
2096 if (getDiagnostics().getSuppressSystemWarnings() &&
2097 (Context.getSourceManager().isInSystemHeader(Old->getLocation()) ||
2098 Context.getSourceManager().isInSystemHeader(New->getLocation())))
2101 Diag(New->getLocation(), diag::ext_redefinition_of_typedef)
2102 << New->getDeclName();
2103 Diag(Old->getLocation(), diag::note_previous_definition);
2106 /// DeclhasAttr - returns true if decl Declaration already has the target
2108 static bool DeclHasAttr(const Decl *D, const Attr *A) {
2109 const OwnershipAttr *OA = dyn_cast<OwnershipAttr>(A);
2110 const AnnotateAttr *Ann = dyn_cast<AnnotateAttr>(A);
2111 for (const auto *i : D->attrs())
2112 if (i->getKind() == A->getKind()) {
2114 if (Ann->getAnnotation() == cast<AnnotateAttr>(i)->getAnnotation())
2118 // FIXME: Don't hardcode this check
2119 if (OA && isa<OwnershipAttr>(i))
2120 return OA->getOwnKind() == cast<OwnershipAttr>(i)->getOwnKind();
2127 static bool isAttributeTargetADefinition(Decl *D) {
2128 if (VarDecl *VD = dyn_cast<VarDecl>(D))
2129 return VD->isThisDeclarationADefinition();
2130 if (TagDecl *TD = dyn_cast<TagDecl>(D))
2131 return TD->isCompleteDefinition() || TD->isBeingDefined();
2135 /// Merge alignment attributes from \p Old to \p New, taking into account the
2136 /// special semantics of C11's _Alignas specifier and C++11's alignas attribute.
2138 /// \return \c true if any attributes were added to \p New.
2139 static bool mergeAlignedAttrs(Sema &S, NamedDecl *New, Decl *Old) {
2140 // Look for alignas attributes on Old, and pick out whichever attribute
2141 // specifies the strictest alignment requirement.
2142 AlignedAttr *OldAlignasAttr = nullptr;
2143 AlignedAttr *OldStrictestAlignAttr = nullptr;
2144 unsigned OldAlign = 0;
2145 for (auto *I : Old->specific_attrs<AlignedAttr>()) {
2146 // FIXME: We have no way of representing inherited dependent alignments
2148 // template<int A, int B> struct alignas(A) X;
2149 // template<int A, int B> struct alignas(B) X {};
2150 // For now, we just ignore any alignas attributes which are not on the
2151 // definition in such a case.
2152 if (I->isAlignmentDependent())
2158 unsigned Align = I->getAlignment(S.Context);
2159 if (Align > OldAlign) {
2161 OldStrictestAlignAttr = I;
2165 // Look for alignas attributes on New.
2166 AlignedAttr *NewAlignasAttr = nullptr;
2167 unsigned NewAlign = 0;
2168 for (auto *I : New->specific_attrs<AlignedAttr>()) {
2169 if (I->isAlignmentDependent())
2175 unsigned Align = I->getAlignment(S.Context);
2176 if (Align > NewAlign)
2180 if (OldAlignasAttr && NewAlignasAttr && OldAlign != NewAlign) {
2181 // Both declarations have 'alignas' attributes. We require them to match.
2182 // C++11 [dcl.align]p6 and C11 6.7.5/7 both come close to saying this, but
2183 // fall short. (If two declarations both have alignas, they must both match
2184 // every definition, and so must match each other if there is a definition.)
2186 // If either declaration only contains 'alignas(0)' specifiers, then it
2187 // specifies the natural alignment for the type.
2188 if (OldAlign == 0 || NewAlign == 0) {
2190 if (ValueDecl *VD = dyn_cast<ValueDecl>(New))
2193 Ty = S.Context.getTagDeclType(cast<TagDecl>(New));
2196 OldAlign = S.Context.getTypeAlign(Ty);
2198 NewAlign = S.Context.getTypeAlign(Ty);
2201 if (OldAlign != NewAlign) {
2202 S.Diag(NewAlignasAttr->getLocation(), diag::err_alignas_mismatch)
2203 << (unsigned)S.Context.toCharUnitsFromBits(OldAlign).getQuantity()
2204 << (unsigned)S.Context.toCharUnitsFromBits(NewAlign).getQuantity();
2205 S.Diag(OldAlignasAttr->getLocation(), diag::note_previous_declaration);
2209 if (OldAlignasAttr && !NewAlignasAttr && isAttributeTargetADefinition(New)) {
2210 // C++11 [dcl.align]p6:
2211 // if any declaration of an entity has an alignment-specifier,
2212 // every defining declaration of that entity shall specify an
2213 // equivalent alignment.
2215 // If the definition of an object does not have an alignment
2216 // specifier, any other declaration of that object shall also
2217 // have no alignment specifier.
2218 S.Diag(New->getLocation(), diag::err_alignas_missing_on_definition)
2220 S.Diag(OldAlignasAttr->getLocation(), diag::note_alignas_on_declaration)
2224 bool AnyAdded = false;
2226 // Ensure we have an attribute representing the strictest alignment.
2227 if (OldAlign > NewAlign) {
2228 AlignedAttr *Clone = OldStrictestAlignAttr->clone(S.Context);
2229 Clone->setInherited(true);
2230 New->addAttr(Clone);
2234 // Ensure we have an alignas attribute if the old declaration had one.
2235 if (OldAlignasAttr && !NewAlignasAttr &&
2236 !(AnyAdded && OldStrictestAlignAttr->isAlignas())) {
2237 AlignedAttr *Clone = OldAlignasAttr->clone(S.Context);
2238 Clone->setInherited(true);
2239 New->addAttr(Clone);
2246 static bool mergeDeclAttribute(Sema &S, NamedDecl *D,
2247 const InheritableAttr *Attr,
2248 Sema::AvailabilityMergeKind AMK) {
2249 InheritableAttr *NewAttr = nullptr;
2250 unsigned AttrSpellingListIndex = Attr->getSpellingListIndex();
2251 if (const auto *AA = dyn_cast<AvailabilityAttr>(Attr))
2252 NewAttr = S.mergeAvailabilityAttr(D, AA->getRange(), AA->getPlatform(),
2253 AA->isImplicit(), AA->getIntroduced(),
2254 AA->getDeprecated(),
2255 AA->getObsoleted(), AA->getUnavailable(),
2256 AA->getMessage(), AA->getStrict(),
2257 AA->getReplacement(), AMK,
2258 AttrSpellingListIndex);
2259 else if (const auto *VA = dyn_cast<VisibilityAttr>(Attr))
2260 NewAttr = S.mergeVisibilityAttr(D, VA->getRange(), VA->getVisibility(),
2261 AttrSpellingListIndex);
2262 else if (const auto *VA = dyn_cast<TypeVisibilityAttr>(Attr))
2263 NewAttr = S.mergeTypeVisibilityAttr(D, VA->getRange(), VA->getVisibility(),
2264 AttrSpellingListIndex);
2265 else if (const auto *ImportA = dyn_cast<DLLImportAttr>(Attr))
2266 NewAttr = S.mergeDLLImportAttr(D, ImportA->getRange(),
2267 AttrSpellingListIndex);
2268 else if (const auto *ExportA = dyn_cast<DLLExportAttr>(Attr))
2269 NewAttr = S.mergeDLLExportAttr(D, ExportA->getRange(),
2270 AttrSpellingListIndex);
2271 else if (const auto *FA = dyn_cast<FormatAttr>(Attr))
2272 NewAttr = S.mergeFormatAttr(D, FA->getRange(), FA->getType(),
2273 FA->getFormatIdx(), FA->getFirstArg(),
2274 AttrSpellingListIndex);
2275 else if (const auto *SA = dyn_cast<SectionAttr>(Attr))
2276 NewAttr = S.mergeSectionAttr(D, SA->getRange(), SA->getName(),
2277 AttrSpellingListIndex);
2278 else if (const auto *IA = dyn_cast<MSInheritanceAttr>(Attr))
2279 NewAttr = S.mergeMSInheritanceAttr(D, IA->getRange(), IA->getBestCase(),
2280 AttrSpellingListIndex,
2281 IA->getSemanticSpelling());
2282 else if (const auto *AA = dyn_cast<AlwaysInlineAttr>(Attr))
2283 NewAttr = S.mergeAlwaysInlineAttr(D, AA->getRange(),
2284 &S.Context.Idents.get(AA->getSpelling()),
2285 AttrSpellingListIndex);
2286 else if (const auto *MA = dyn_cast<MinSizeAttr>(Attr))
2287 NewAttr = S.mergeMinSizeAttr(D, MA->getRange(), AttrSpellingListIndex);
2288 else if (const auto *OA = dyn_cast<OptimizeNoneAttr>(Attr))
2289 NewAttr = S.mergeOptimizeNoneAttr(D, OA->getRange(), AttrSpellingListIndex);
2290 else if (const auto *InternalLinkageA = dyn_cast<InternalLinkageAttr>(Attr))
2291 NewAttr = S.mergeInternalLinkageAttr(
2292 D, InternalLinkageA->getRange(),
2293 &S.Context.Idents.get(InternalLinkageA->getSpelling()),
2294 AttrSpellingListIndex);
2295 else if (const auto *CommonA = dyn_cast<CommonAttr>(Attr))
2296 NewAttr = S.mergeCommonAttr(D, CommonA->getRange(),
2297 &S.Context.Idents.get(CommonA->getSpelling()),
2298 AttrSpellingListIndex);
2299 else if (isa<AlignedAttr>(Attr))
2300 // AlignedAttrs are handled separately, because we need to handle all
2301 // such attributes on a declaration at the same time.
2303 else if ((isa<DeprecatedAttr>(Attr) || isa<UnavailableAttr>(Attr)) &&
2304 (AMK == Sema::AMK_Override ||
2305 AMK == Sema::AMK_ProtocolImplementation))
2307 else if (Attr->duplicatesAllowed() || !DeclHasAttr(D, Attr))
2308 NewAttr = cast<InheritableAttr>(Attr->clone(S.Context));
2311 NewAttr->setInherited(true);
2312 D->addAttr(NewAttr);
2313 if (isa<MSInheritanceAttr>(NewAttr))
2314 S.Consumer.AssignInheritanceModel(cast<CXXRecordDecl>(D));
2321 static const Decl *getDefinition(const Decl *D) {
2322 if (const TagDecl *TD = dyn_cast<TagDecl>(D))
2323 return TD->getDefinition();
2324 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
2325 const VarDecl *Def = VD->getDefinition();
2328 return VD->getActingDefinition();
2330 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D))
2331 return FD->getDefinition();
2335 static bool hasAttribute(const Decl *D, attr::Kind Kind) {
2336 for (const auto *Attribute : D->attrs())
2337 if (Attribute->getKind() == Kind)
2342 /// checkNewAttributesAfterDef - If we already have a definition, check that
2343 /// there are no new attributes in this declaration.
2344 static void checkNewAttributesAfterDef(Sema &S, Decl *New, const Decl *Old) {
2345 if (!New->hasAttrs())
2348 const Decl *Def = getDefinition(Old);
2349 if (!Def || Def == New)
2352 AttrVec &NewAttributes = New->getAttrs();
2353 for (unsigned I = 0, E = NewAttributes.size(); I != E;) {
2354 const Attr *NewAttribute = NewAttributes[I];
2356 if (isa<AliasAttr>(NewAttribute) || isa<IFuncAttr>(NewAttribute)) {
2357 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(New)) {
2358 Sema::SkipBodyInfo SkipBody;
2359 S.CheckForFunctionRedefinition(FD, cast<FunctionDecl>(Def), &SkipBody);
2361 // If we're skipping this definition, drop the "alias" attribute.
2362 if (SkipBody.ShouldSkip) {
2363 NewAttributes.erase(NewAttributes.begin() + I);
2368 VarDecl *VD = cast<VarDecl>(New);
2369 unsigned Diag = cast<VarDecl>(Def)->isThisDeclarationADefinition() ==
2370 VarDecl::TentativeDefinition
2371 ? diag::err_alias_after_tentative
2372 : diag::err_redefinition;
2373 S.Diag(VD->getLocation(), Diag) << VD->getDeclName();
2374 S.Diag(Def->getLocation(), diag::note_previous_definition);
2375 VD->setInvalidDecl();
2381 if (const VarDecl *VD = dyn_cast<VarDecl>(Def)) {
2382 // Tentative definitions are only interesting for the alias check above.
2383 if (VD->isThisDeclarationADefinition() != VarDecl::Definition) {
2389 if (hasAttribute(Def, NewAttribute->getKind())) {
2391 continue; // regular attr merging will take care of validating this.
2394 if (isa<C11NoReturnAttr>(NewAttribute)) {
2395 // C's _Noreturn is allowed to be added to a function after it is defined.
2398 } else if (const AlignedAttr *AA = dyn_cast<AlignedAttr>(NewAttribute)) {
2399 if (AA->isAlignas()) {
2400 // C++11 [dcl.align]p6:
2401 // if any declaration of an entity has an alignment-specifier,
2402 // every defining declaration of that entity shall specify an
2403 // equivalent alignment.
2405 // If the definition of an object does not have an alignment
2406 // specifier, any other declaration of that object shall also
2407 // have no alignment specifier.
2408 S.Diag(Def->getLocation(), diag::err_alignas_missing_on_definition)
2410 S.Diag(NewAttribute->getLocation(), diag::note_alignas_on_declaration)
2412 NewAttributes.erase(NewAttributes.begin() + I);
2418 S.Diag(NewAttribute->getLocation(),
2419 diag::warn_attribute_precede_definition);
2420 S.Diag(Def->getLocation(), diag::note_previous_definition);
2421 NewAttributes.erase(NewAttributes.begin() + I);
2426 /// mergeDeclAttributes - Copy attributes from the Old decl to the New one.
2427 void Sema::mergeDeclAttributes(NamedDecl *New, Decl *Old,
2428 AvailabilityMergeKind AMK) {
2429 if (UsedAttr *OldAttr = Old->getMostRecentDecl()->getAttr<UsedAttr>()) {
2430 UsedAttr *NewAttr = OldAttr->clone(Context);
2431 NewAttr->setInherited(true);
2432 New->addAttr(NewAttr);
2435 if (!Old->hasAttrs() && !New->hasAttrs())
2438 // Attributes declared post-definition are currently ignored.
2439 checkNewAttributesAfterDef(*this, New, Old);
2441 if (AsmLabelAttr *NewA = New->getAttr<AsmLabelAttr>()) {
2442 if (AsmLabelAttr *OldA = Old->getAttr<AsmLabelAttr>()) {
2443 if (OldA->getLabel() != NewA->getLabel()) {
2444 // This redeclaration changes __asm__ label.
2445 Diag(New->getLocation(), diag::err_different_asm_label);
2446 Diag(OldA->getLocation(), diag::note_previous_declaration);
2448 } else if (Old->isUsed()) {
2449 // This redeclaration adds an __asm__ label to a declaration that has
2450 // already been ODR-used.
2451 Diag(New->getLocation(), diag::err_late_asm_label_name)
2452 << isa<FunctionDecl>(Old) << New->getAttr<AsmLabelAttr>()->getRange();
2456 // Re-declaration cannot add abi_tag's.
2457 if (const auto *NewAbiTagAttr = New->getAttr<AbiTagAttr>()) {
2458 if (const auto *OldAbiTagAttr = Old->getAttr<AbiTagAttr>()) {
2459 for (const auto &NewTag : NewAbiTagAttr->tags()) {
2460 if (std::find(OldAbiTagAttr->tags_begin(), OldAbiTagAttr->tags_end(),
2461 NewTag) == OldAbiTagAttr->tags_end()) {
2462 Diag(NewAbiTagAttr->getLocation(),
2463 diag::err_new_abi_tag_on_redeclaration)
2465 Diag(OldAbiTagAttr->getLocation(), diag::note_previous_declaration);
2469 Diag(NewAbiTagAttr->getLocation(), diag::err_abi_tag_on_redeclaration);
2470 Diag(Old->getLocation(), diag::note_previous_declaration);
2474 if (!Old->hasAttrs())
2477 bool foundAny = New->hasAttrs();
2479 // Ensure that any moving of objects within the allocated map is done before
2481 if (!foundAny) New->setAttrs(AttrVec());
2483 for (auto *I : Old->specific_attrs<InheritableAttr>()) {
2484 // Ignore deprecated/unavailable/availability attributes if requested.
2485 AvailabilityMergeKind LocalAMK = AMK_None;
2486 if (isa<DeprecatedAttr>(I) ||
2487 isa<UnavailableAttr>(I) ||
2488 isa<AvailabilityAttr>(I)) {
2493 case AMK_Redeclaration:
2495 case AMK_ProtocolImplementation:
2502 if (isa<UsedAttr>(I))
2505 if (mergeDeclAttribute(*this, New, I, LocalAMK))
2509 if (mergeAlignedAttrs(*this, New, Old))
2512 if (!foundAny) New->dropAttrs();
2515 /// mergeParamDeclAttributes - Copy attributes from the old parameter
2517 static void mergeParamDeclAttributes(ParmVarDecl *newDecl,
2518 const ParmVarDecl *oldDecl,
2520 // C++11 [dcl.attr.depend]p2:
2521 // The first declaration of a function shall specify the
2522 // carries_dependency attribute for its declarator-id if any declaration
2523 // of the function specifies the carries_dependency attribute.
2524 const CarriesDependencyAttr *CDA = newDecl->getAttr<CarriesDependencyAttr>();
2525 if (CDA && !oldDecl->hasAttr<CarriesDependencyAttr>()) {
2526 S.Diag(CDA->getLocation(),
2527 diag::err_carries_dependency_missing_on_first_decl) << 1/*Param*/;
2528 // Find the first declaration of the parameter.
2529 // FIXME: Should we build redeclaration chains for function parameters?
2530 const FunctionDecl *FirstFD =
2531 cast<FunctionDecl>(oldDecl->getDeclContext())->getFirstDecl();
2532 const ParmVarDecl *FirstVD =
2533 FirstFD->getParamDecl(oldDecl->getFunctionScopeIndex());
2534 S.Diag(FirstVD->getLocation(),
2535 diag::note_carries_dependency_missing_first_decl) << 1/*Param*/;
2538 if (!oldDecl->hasAttrs())
2541 bool foundAny = newDecl->hasAttrs();
2543 // Ensure that any moving of objects within the allocated map is
2544 // done before we process them.
2545 if (!foundAny) newDecl->setAttrs(AttrVec());
2547 for (const auto *I : oldDecl->specific_attrs<InheritableParamAttr>()) {
2548 if (!DeclHasAttr(newDecl, I)) {
2549 InheritableAttr *newAttr =
2550 cast<InheritableParamAttr>(I->clone(S.Context));
2551 newAttr->setInherited(true);
2552 newDecl->addAttr(newAttr);
2557 if (!foundAny) newDecl->dropAttrs();
2560 static void mergeParamDeclTypes(ParmVarDecl *NewParam,
2561 const ParmVarDecl *OldParam,
2563 if (auto Oldnullability = OldParam->getType()->getNullability(S.Context)) {
2564 if (auto Newnullability = NewParam->getType()->getNullability(S.Context)) {
2565 if (*Oldnullability != *Newnullability) {
2566 S.Diag(NewParam->getLocation(), diag::warn_mismatched_nullability_attr)
2567 << DiagNullabilityKind(
2569 ((NewParam->getObjCDeclQualifier() & Decl::OBJC_TQ_CSNullability)
2571 << DiagNullabilityKind(
2573 ((OldParam->getObjCDeclQualifier() & Decl::OBJC_TQ_CSNullability)
2575 S.Diag(OldParam->getLocation(), diag::note_previous_declaration);
2578 QualType NewT = NewParam->getType();
2579 NewT = S.Context.getAttributedType(
2580 AttributedType::getNullabilityAttrKind(*Oldnullability),
2582 NewParam->setType(NewT);
2589 /// Used in MergeFunctionDecl to keep track of function parameters in
2591 struct GNUCompatibleParamWarning {
2592 ParmVarDecl *OldParm;
2593 ParmVarDecl *NewParm;
2594 QualType PromotedType;
2597 } // end anonymous namespace
2599 /// getSpecialMember - get the special member enum for a method.
2600 Sema::CXXSpecialMember Sema::getSpecialMember(const CXXMethodDecl *MD) {
2601 if (const CXXConstructorDecl *Ctor = dyn_cast<CXXConstructorDecl>(MD)) {
2602 if (Ctor->isDefaultConstructor())
2603 return Sema::CXXDefaultConstructor;
2605 if (Ctor->isCopyConstructor())
2606 return Sema::CXXCopyConstructor;
2608 if (Ctor->isMoveConstructor())
2609 return Sema::CXXMoveConstructor;
2610 } else if (isa<CXXDestructorDecl>(MD)) {
2611 return Sema::CXXDestructor;
2612 } else if (MD->isCopyAssignmentOperator()) {
2613 return Sema::CXXCopyAssignment;
2614 } else if (MD->isMoveAssignmentOperator()) {
2615 return Sema::CXXMoveAssignment;
2618 return Sema::CXXInvalid;
2621 // Determine whether the previous declaration was a definition, implicit
2622 // declaration, or a declaration.
2623 template <typename T>
2624 static std::pair<diag::kind, SourceLocation>
2625 getNoteDiagForInvalidRedeclaration(const T *Old, const T *New) {
2626 diag::kind PrevDiag;
2627 SourceLocation OldLocation = Old->getLocation();
2628 if (Old->isThisDeclarationADefinition())
2629 PrevDiag = diag::note_previous_definition;
2630 else if (Old->isImplicit()) {
2631 PrevDiag = diag::note_previous_implicit_declaration;
2632 if (OldLocation.isInvalid())
2633 OldLocation = New->getLocation();
2635 PrevDiag = diag::note_previous_declaration;
2636 return std::make_pair(PrevDiag, OldLocation);
2639 /// canRedefineFunction - checks if a function can be redefined. Currently,
2640 /// only extern inline functions can be redefined, and even then only in
2642 static bool canRedefineFunction(const FunctionDecl *FD,
2643 const LangOptions& LangOpts) {
2644 return ((FD->hasAttr<GNUInlineAttr>() || LangOpts.GNUInline) &&
2645 !LangOpts.CPlusPlus &&
2646 FD->isInlineSpecified() &&
2647 FD->getStorageClass() == SC_Extern);
2650 const AttributedType *Sema::getCallingConvAttributedType(QualType T) const {
2651 const AttributedType *AT = T->getAs<AttributedType>();
2652 while (AT && !AT->isCallingConv())
2653 AT = AT->getModifiedType()->getAs<AttributedType>();
2657 template <typename T>
2658 static bool haveIncompatibleLanguageLinkages(const T *Old, const T *New) {
2659 const DeclContext *DC = Old->getDeclContext();
2663 LanguageLinkage OldLinkage = Old->getLanguageLinkage();
2664 if (OldLinkage == CXXLanguageLinkage && New->isInExternCContext())
2666 if (OldLinkage == CLanguageLinkage && New->isInExternCXXContext())
2671 template<typename T> static bool isExternC(T *D) { return D->isExternC(); }
2672 static bool isExternC(VarTemplateDecl *) { return false; }
2674 /// \brief Check whether a redeclaration of an entity introduced by a
2675 /// using-declaration is valid, given that we know it's not an overload
2676 /// (nor a hidden tag declaration).
2677 template<typename ExpectedDecl>
2678 static bool checkUsingShadowRedecl(Sema &S, UsingShadowDecl *OldS,
2679 ExpectedDecl *New) {
2680 // C++11 [basic.scope.declarative]p4:
2681 // Given a set of declarations in a single declarative region, each of
2682 // which specifies the same unqualified name,
2683 // -- they shall all refer to the same entity, or all refer to functions
2684 // and function templates; or
2685 // -- exactly one declaration shall declare a class name or enumeration
2686 // name that is not a typedef name and the other declarations shall all
2687 // refer to the same variable or enumerator, or all refer to functions
2688 // and function templates; in this case the class name or enumeration
2689 // name is hidden (3.3.10).
2691 // C++11 [namespace.udecl]p14:
2692 // If a function declaration in namespace scope or block scope has the
2693 // same name and the same parameter-type-list as a function introduced
2694 // by a using-declaration, and the declarations do not declare the same
2695 // function, the program is ill-formed.
2697 auto *Old = dyn_cast<ExpectedDecl>(OldS->getTargetDecl());
2699 !Old->getDeclContext()->getRedeclContext()->Equals(
2700 New->getDeclContext()->getRedeclContext()) &&
2701 !(isExternC(Old) && isExternC(New)))
2705 S.Diag(New->getLocation(), diag::err_using_decl_conflict_reverse);
2706 S.Diag(OldS->getTargetDecl()->getLocation(), diag::note_using_decl_target);
2707 S.Diag(OldS->getUsingDecl()->getLocation(), diag::note_using_decl) << 0;
2713 static bool hasIdenticalPassObjectSizeAttrs(const FunctionDecl *A,
2714 const FunctionDecl *B) {
2715 assert(A->getNumParams() == B->getNumParams());
2717 auto AttrEq = [](const ParmVarDecl *A, const ParmVarDecl *B) {
2718 const auto *AttrA = A->getAttr<PassObjectSizeAttr>();
2719 const auto *AttrB = B->getAttr<PassObjectSizeAttr>();
2722 return AttrA && AttrB && AttrA->getType() == AttrB->getType();
2725 return std::equal(A->param_begin(), A->param_end(), B->param_begin(), AttrEq);
2728 /// MergeFunctionDecl - We just parsed a function 'New' from
2729 /// declarator D which has the same name and scope as a previous
2730 /// declaration 'Old'. Figure out how to resolve this situation,
2731 /// merging decls or emitting diagnostics as appropriate.
2733 /// In C++, New and Old must be declarations that are not
2734 /// overloaded. Use IsOverload to determine whether New and Old are
2735 /// overloaded, and to select the Old declaration that New should be
2738 /// Returns true if there was an error, false otherwise.
2739 bool Sema::MergeFunctionDecl(FunctionDecl *New, NamedDecl *&OldD,
2740 Scope *S, bool MergeTypeWithOld) {
2741 // Verify the old decl was also a function.
2742 FunctionDecl *Old = OldD->getAsFunction();
2744 if (UsingShadowDecl *Shadow = dyn_cast<UsingShadowDecl>(OldD)) {
2745 if (New->getFriendObjectKind()) {
2746 Diag(New->getLocation(), diag::err_using_decl_friend);
2747 Diag(Shadow->getTargetDecl()->getLocation(),
2748 diag::note_using_decl_target);
2749 Diag(Shadow->getUsingDecl()->getLocation(),
2750 diag::note_using_decl) << 0;
2754 // Check whether the two declarations might declare the same function.
2755 if (checkUsingShadowRedecl<FunctionDecl>(*this, Shadow, New))
2757 OldD = Old = cast<FunctionDecl>(Shadow->getTargetDecl());
2759 Diag(New->getLocation(), diag::err_redefinition_different_kind)
2760 << New->getDeclName();
2761 Diag(OldD->getLocation(), diag::note_previous_definition);
2766 // If the old declaration is invalid, just give up here.
2767 if (Old->isInvalidDecl())
2770 diag::kind PrevDiag;
2771 SourceLocation OldLocation;
2772 std::tie(PrevDiag, OldLocation) =
2773 getNoteDiagForInvalidRedeclaration(Old, New);
2775 // Don't complain about this if we're in GNU89 mode and the old function
2776 // is an extern inline function.
2777 // Don't complain about specializations. They are not supposed to have
2779 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) &&
2780 New->getStorageClass() == SC_Static &&
2781 Old->hasExternalFormalLinkage() &&
2782 !New->getTemplateSpecializationInfo() &&
2783 !canRedefineFunction(Old, getLangOpts())) {
2784 if (getLangOpts().MicrosoftExt) {
2785 Diag(New->getLocation(), diag::ext_static_non_static) << New;
2786 Diag(OldLocation, PrevDiag);
2788 Diag(New->getLocation(), diag::err_static_non_static) << New;
2789 Diag(OldLocation, PrevDiag);
2794 if (New->hasAttr<InternalLinkageAttr>() &&
2795 !Old->hasAttr<InternalLinkageAttr>()) {
2796 Diag(New->getLocation(), diag::err_internal_linkage_redeclaration)
2797 << New->getDeclName();
2798 Diag(Old->getLocation(), diag::note_previous_definition);
2799 New->dropAttr<InternalLinkageAttr>();
2802 // If a function is first declared with a calling convention, but is later
2803 // declared or defined without one, all following decls assume the calling
2804 // convention of the first.
2806 // It's OK if a function is first declared without a calling convention,
2807 // but is later declared or defined with the default calling convention.
2809 // To test if either decl has an explicit calling convention, we look for
2810 // AttributedType sugar nodes on the type as written. If they are missing or
2811 // were canonicalized away, we assume the calling convention was implicit.
2813 // Note also that we DO NOT return at this point, because we still have
2814 // other tests to run.
2815 QualType OldQType = Context.getCanonicalType(Old->getType());
2816 QualType NewQType = Context.getCanonicalType(New->getType());
2817 const FunctionType *OldType = cast<FunctionType>(OldQType);
2818 const FunctionType *NewType = cast<FunctionType>(NewQType);
2819 FunctionType::ExtInfo OldTypeInfo = OldType->getExtInfo();
2820 FunctionType::ExtInfo NewTypeInfo = NewType->getExtInfo();
2821 bool RequiresAdjustment = false;
2823 if (OldTypeInfo.getCC() != NewTypeInfo.getCC()) {
2824 FunctionDecl *First = Old->getFirstDecl();
2825 const FunctionType *FT =
2826 First->getType().getCanonicalType()->castAs<FunctionType>();
2827 FunctionType::ExtInfo FI = FT->getExtInfo();
2828 bool NewCCExplicit = getCallingConvAttributedType(New->getType());
2829 if (!NewCCExplicit) {
2830 // Inherit the CC from the previous declaration if it was specified
2831 // there but not here.
2832 NewTypeInfo = NewTypeInfo.withCallingConv(OldTypeInfo.getCC());
2833 RequiresAdjustment = true;
2835 // Calling conventions aren't compatible, so complain.
2836 bool FirstCCExplicit = getCallingConvAttributedType(First->getType());
2837 Diag(New->getLocation(), diag::err_cconv_change)
2838 << FunctionType::getNameForCallConv(NewTypeInfo.getCC())
2840 << (!FirstCCExplicit ? "" :
2841 FunctionType::getNameForCallConv(FI.getCC()));
2843 // Put the note on the first decl, since it is the one that matters.
2844 Diag(First->getLocation(), diag::note_previous_declaration);
2849 // FIXME: diagnose the other way around?
2850 if (OldTypeInfo.getNoReturn() && !NewTypeInfo.getNoReturn()) {
2851 NewTypeInfo = NewTypeInfo.withNoReturn(true);
2852 RequiresAdjustment = true;
2855 // Merge regparm attribute.
2856 if (OldTypeInfo.getHasRegParm() != NewTypeInfo.getHasRegParm() ||
2857 OldTypeInfo.getRegParm() != NewTypeInfo.getRegParm()) {
2858 if (NewTypeInfo.getHasRegParm()) {
2859 Diag(New->getLocation(), diag::err_regparm_mismatch)
2860 << NewType->getRegParmType()
2861 << OldType->getRegParmType();
2862 Diag(OldLocation, diag::note_previous_declaration);
2866 NewTypeInfo = NewTypeInfo.withRegParm(OldTypeInfo.getRegParm());
2867 RequiresAdjustment = true;
2870 // Merge ns_returns_retained attribute.
2871 if (OldTypeInfo.getProducesResult() != NewTypeInfo.getProducesResult()) {
2872 if (NewTypeInfo.getProducesResult()) {
2873 Diag(New->getLocation(), diag::err_returns_retained_mismatch);
2874 Diag(OldLocation, diag::note_previous_declaration);
2878 NewTypeInfo = NewTypeInfo.withProducesResult(true);
2879 RequiresAdjustment = true;
2882 if (RequiresAdjustment) {
2883 const FunctionType *AdjustedType = New->getType()->getAs<FunctionType>();
2884 AdjustedType = Context.adjustFunctionType(AdjustedType, NewTypeInfo);
2885 New->setType(QualType(AdjustedType, 0));
2886 NewQType = Context.getCanonicalType(New->getType());
2887 NewType = cast<FunctionType>(NewQType);
2890 // If this redeclaration makes the function inline, we may need to add it to
2891 // UndefinedButUsed.
2892 if (!Old->isInlined() && New->isInlined() &&
2893 !New->hasAttr<GNUInlineAttr>() &&
2894 !getLangOpts().GNUInline &&
2895 Old->isUsed(false) &&
2896 !Old->isDefined() && !New->isThisDeclarationADefinition())
2897 UndefinedButUsed.insert(std::make_pair(Old->getCanonicalDecl(),
2900 // If this redeclaration makes it newly gnu_inline, we don't want to warn
2902 if (New->hasAttr<GNUInlineAttr>() &&
2903 Old->isInlined() && !Old->hasAttr<GNUInlineAttr>()) {
2904 UndefinedButUsed.erase(Old->getCanonicalDecl());
2907 // If pass_object_size params don't match up perfectly, this isn't a valid
2909 if (Old->getNumParams() > 0 && Old->getNumParams() == New->getNumParams() &&
2910 !hasIdenticalPassObjectSizeAttrs(Old, New)) {
2911 Diag(New->getLocation(), diag::err_different_pass_object_size_params)
2912 << New->getDeclName();
2913 Diag(OldLocation, PrevDiag) << Old << Old->getType();
2917 if (getLangOpts().CPlusPlus) {
2919 // Certain function declarations cannot be overloaded:
2920 // -- Function declarations that differ only in the return type
2921 // cannot be overloaded.
2923 // Go back to the type source info to compare the declared return types,
2924 // per C++1y [dcl.type.auto]p13:
2925 // Redeclarations or specializations of a function or function template
2926 // with a declared return type that uses a placeholder type shall also
2927 // use that placeholder, not a deduced type.
2928 QualType OldDeclaredReturnType =
2929 (Old->getTypeSourceInfo()
2930 ? Old->getTypeSourceInfo()->getType()->castAs<FunctionType>()
2931 : OldType)->getReturnType();
2932 QualType NewDeclaredReturnType =
2933 (New->getTypeSourceInfo()
2934 ? New->getTypeSourceInfo()->getType()->castAs<FunctionType>()
2935 : NewType)->getReturnType();
2937 if (!Context.hasSameType(OldDeclaredReturnType, NewDeclaredReturnType) &&
2938 !((NewQType->isDependentType() || OldQType->isDependentType()) &&
2939 New->isLocalExternDecl())) {
2940 if (NewDeclaredReturnType->isObjCObjectPointerType() &&
2941 OldDeclaredReturnType->isObjCObjectPointerType())
2942 ResQT = Context.mergeObjCGCQualifiers(NewQType, OldQType);
2943 if (ResQT.isNull()) {
2944 if (New->isCXXClassMember() && New->isOutOfLine())
2945 Diag(New->getLocation(), diag::err_member_def_does_not_match_ret_type)
2946 << New << New->getReturnTypeSourceRange();
2948 Diag(New->getLocation(), diag::err_ovl_diff_return_type)
2949 << New->getReturnTypeSourceRange();
2950 Diag(OldLocation, PrevDiag) << Old << Old->getType()
2951 << Old->getReturnTypeSourceRange();
2958 QualType OldReturnType = OldType->getReturnType();
2959 QualType NewReturnType = cast<FunctionType>(NewQType)->getReturnType();
2960 if (OldReturnType != NewReturnType) {
2961 // If this function has a deduced return type and has already been
2962 // defined, copy the deduced value from the old declaration.
2963 AutoType *OldAT = Old->getReturnType()->getContainedAutoType();
2964 if (OldAT && OldAT->isDeduced()) {
2966 SubstAutoType(New->getType(),
2967 OldAT->isDependentType() ? Context.DependentTy
2968 : OldAT->getDeducedType()));
2969 NewQType = Context.getCanonicalType(
2970 SubstAutoType(NewQType,
2971 OldAT->isDependentType() ? Context.DependentTy
2972 : OldAT->getDeducedType()));
2976 const CXXMethodDecl *OldMethod = dyn_cast<CXXMethodDecl>(Old);
2977 CXXMethodDecl *NewMethod = dyn_cast<CXXMethodDecl>(New);
2978 if (OldMethod && NewMethod) {
2979 // Preserve triviality.
2980 NewMethod->setTrivial(OldMethod->isTrivial());
2982 // MSVC allows explicit template specialization at class scope:
2983 // 2 CXXMethodDecls referring to the same function will be injected.
2984 // We don't want a redeclaration error.
2985 bool IsClassScopeExplicitSpecialization =
2986 OldMethod->isFunctionTemplateSpecialization() &&
2987 NewMethod->isFunctionTemplateSpecialization();
2988 bool isFriend = NewMethod->getFriendObjectKind();
2990 if (!isFriend && NewMethod->getLexicalDeclContext()->isRecord() &&
2991 !IsClassScopeExplicitSpecialization) {
2992 // -- Member function declarations with the same name and the
2993 // same parameter types cannot be overloaded if any of them
2994 // is a static member function declaration.
2995 if (OldMethod->isStatic() != NewMethod->isStatic()) {
2996 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member);
2997 Diag(OldLocation, PrevDiag) << Old << Old->getType();
3001 // C++ [class.mem]p1:
3002 // [...] A member shall not be declared twice in the
3003 // member-specification, except that a nested class or member
3004 // class template can be declared and then later defined.
3005 if (ActiveTemplateInstantiations.empty()) {
3007 if (isa<CXXConstructorDecl>(OldMethod))
3008 NewDiag = diag::err_constructor_redeclared;
3009 else if (isa<CXXDestructorDecl>(NewMethod))
3010 NewDiag = diag::err_destructor_redeclared;
3011 else if (isa<CXXConversionDecl>(NewMethod))
3012 NewDiag = diag::err_conv_function_redeclared;
3014 NewDiag = diag::err_member_redeclared;
3016 Diag(New->getLocation(), NewDiag);
3018 Diag(New->getLocation(), diag::err_member_redeclared_in_instantiation)
3019 << New << New->getType();
3021 Diag(OldLocation, PrevDiag) << Old << Old->getType();
3024 // Complain if this is an explicit declaration of a special
3025 // member that was initially declared implicitly.
3027 // As an exception, it's okay to befriend such methods in order
3028 // to permit the implicit constructor/destructor/operator calls.
3029 } else if (OldMethod->isImplicit()) {
3031 NewMethod->setImplicit();
3033 Diag(NewMethod->getLocation(),
3034 diag::err_definition_of_implicitly_declared_member)
3035 << New << getSpecialMember(OldMethod);
3038 } else if (OldMethod->getFirstDecl()->isExplicitlyDefaulted() && !isFriend) {
3039 Diag(NewMethod->getLocation(),
3040 diag::err_definition_of_explicitly_defaulted_member)
3041 << getSpecialMember(OldMethod);
3046 // C++11 [dcl.attr.noreturn]p1:
3047 // The first declaration of a function shall specify the noreturn
3048 // attribute if any declaration of that function specifies the noreturn
3050 const CXX11NoReturnAttr *NRA = New->getAttr<CXX11NoReturnAttr>();
3051 if (NRA && !Old->hasAttr<CXX11NoReturnAttr>()) {
3052 Diag(NRA->getLocation(), diag::err_noreturn_missing_on_first_decl);
3053 Diag(Old->getFirstDecl()->getLocation(),
3054 diag::note_noreturn_missing_first_decl);
3057 // C++11 [dcl.attr.depend]p2:
3058 // The first declaration of a function shall specify the
3059 // carries_dependency attribute for its declarator-id if any declaration
3060 // of the function specifies the carries_dependency attribute.
3061 const CarriesDependencyAttr *CDA = New->getAttr<CarriesDependencyAttr>();
3062 if (CDA && !Old->hasAttr<CarriesDependencyAttr>()) {
3063 Diag(CDA->getLocation(),
3064 diag::err_carries_dependency_missing_on_first_decl) << 0/*Function*/;
3065 Diag(Old->getFirstDecl()->getLocation(),
3066 diag::note_carries_dependency_missing_first_decl) << 0/*Function*/;
3070 // All declarations for a function shall agree exactly in both the
3071 // return type and the parameter-type-list.
3072 // We also want to respect all the extended bits except noreturn.
3074 // noreturn should now match unless the old type info didn't have it.
3075 QualType OldQTypeForComparison = OldQType;
3076 if (!OldTypeInfo.getNoReturn() && NewTypeInfo.getNoReturn()) {
3077 assert(OldQType == QualType(OldType, 0));
3078 const FunctionType *OldTypeForComparison
3079 = Context.adjustFunctionType(OldType, OldTypeInfo.withNoReturn(true));
3080 OldQTypeForComparison = QualType(OldTypeForComparison, 0);
3081 assert(OldQTypeForComparison.isCanonical());
3084 if (haveIncompatibleLanguageLinkages(Old, New)) {
3085 // As a special case, retain the language linkage from previous
3086 // declarations of a friend function as an extension.
3088 // This liberal interpretation of C++ [class.friend]p3 matches GCC/MSVC
3089 // and is useful because there's otherwise no way to specify language
3090 // linkage within class scope.
3092 // Check cautiously as the friend object kind isn't yet complete.
3093 if (New->getFriendObjectKind() != Decl::FOK_None) {
3094 Diag(New->getLocation(), diag::ext_retained_language_linkage) << New;
3095 Diag(OldLocation, PrevDiag);
3097 Diag(New->getLocation(), diag::err_different_language_linkage) << New;
3098 Diag(OldLocation, PrevDiag);
3103 if (OldQTypeForComparison == NewQType)
3104 return MergeCompatibleFunctionDecls(New, Old, S, MergeTypeWithOld);
3106 if ((NewQType->isDependentType() || OldQType->isDependentType()) &&
3107 New->isLocalExternDecl()) {
3108 // It's OK if we couldn't merge types for a local function declaraton
3109 // if either the old or new type is dependent. We'll merge the types
3110 // when we instantiate the function.
3114 // Fall through for conflicting redeclarations and redefinitions.
3117 // C: Function types need to be compatible, not identical. This handles
3118 // duplicate function decls like "void f(int); void f(enum X);" properly.
3119 if (!getLangOpts().CPlusPlus &&
3120 Context.typesAreCompatible(OldQType, NewQType)) {
3121 const FunctionType *OldFuncType = OldQType->getAs<FunctionType>();
3122 const FunctionType *NewFuncType = NewQType->getAs<FunctionType>();
3123 const FunctionProtoType *OldProto = nullptr;
3124 if (MergeTypeWithOld && isa<FunctionNoProtoType>(NewFuncType) &&
3125 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) {
3126 // The old declaration provided a function prototype, but the
3127 // new declaration does not. Merge in the prototype.
3128 assert(!OldProto->hasExceptionSpec() && "Exception spec in C");
3129 SmallVector<QualType, 16> ParamTypes(OldProto->param_types());
3131 Context.getFunctionType(NewFuncType->getReturnType(), ParamTypes,
3132 OldProto->getExtProtoInfo());
3133 New->setType(NewQType);
3134 New->setHasInheritedPrototype();
3136 // Synthesize parameters with the same types.
3137 SmallVector<ParmVarDecl*, 16> Params;
3138 for (const auto &ParamType : OldProto->param_types()) {
3139 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, SourceLocation(),
3140 SourceLocation(), nullptr,
3141 ParamType, /*TInfo=*/nullptr,
3143 Param->setScopeInfo(0, Params.size());
3144 Param->setImplicit();
3145 Params.push_back(Param);
3148 New->setParams(Params);
3151 return MergeCompatibleFunctionDecls(New, Old, S, MergeTypeWithOld);
3154 // GNU C permits a K&R definition to follow a prototype declaration
3155 // if the declared types of the parameters in the K&R definition
3156 // match the types in the prototype declaration, even when the
3157 // promoted types of the parameters from the K&R definition differ
3158 // from the types in the prototype. GCC then keeps the types from
3161 // If a variadic prototype is followed by a non-variadic K&R definition,
3162 // the K&R definition becomes variadic. This is sort of an edge case, but
3163 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and
3165 if (!getLangOpts().CPlusPlus &&
3166 Old->hasPrototype() && !New->hasPrototype() &&
3167 New->getType()->getAs<FunctionProtoType>() &&
3168 Old->getNumParams() == New->getNumParams()) {
3169 SmallVector<QualType, 16> ArgTypes;
3170 SmallVector<GNUCompatibleParamWarning, 16> Warnings;
3171 const FunctionProtoType *OldProto
3172 = Old->getType()->getAs<FunctionProtoType>();
3173 const FunctionProtoType *NewProto
3174 = New->getType()->getAs<FunctionProtoType>();
3176 // Determine whether this is the GNU C extension.
3177 QualType MergedReturn = Context.mergeTypes(OldProto->getReturnType(),
3178 NewProto->getReturnType());
3179 bool LooseCompatible = !MergedReturn.isNull();
3180 for (unsigned Idx = 0, End = Old->getNumParams();
3181 LooseCompatible && Idx != End; ++Idx) {
3182 ParmVarDecl *OldParm = Old->getParamDecl(Idx);
3183 ParmVarDecl *NewParm = New->getParamDecl(Idx);
3184 if (Context.typesAreCompatible(OldParm->getType(),
3185 NewProto->getParamType(Idx))) {
3186 ArgTypes.push_back(NewParm->getType());
3187 } else if (Context.typesAreCompatible(OldParm->getType(),
3189 /*CompareUnqualified=*/true)) {
3190 GNUCompatibleParamWarning Warn = { OldParm, NewParm,
3191 NewProto->getParamType(Idx) };
3192 Warnings.push_back(Warn);
3193 ArgTypes.push_back(NewParm->getType());
3195 LooseCompatible = false;
3198 if (LooseCompatible) {
3199 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) {
3200 Diag(Warnings[Warn].NewParm->getLocation(),
3201 diag::ext_param_promoted_not_compatible_with_prototype)
3202 << Warnings[Warn].PromotedType
3203 << Warnings[Warn].OldParm->getType();
3204 if (Warnings[Warn].OldParm->getLocation().isValid())
3205 Diag(Warnings[Warn].OldParm->getLocation(),
3206 diag::note_previous_declaration);
3209 if (MergeTypeWithOld)
3210 New->setType(Context.getFunctionType(MergedReturn, ArgTypes,
3211 OldProto->getExtProtoInfo()));
3212 return MergeCompatibleFunctionDecls(New, Old, S, MergeTypeWithOld);
3215 // Fall through to diagnose conflicting types.
3218 // A function that has already been declared has been redeclared or
3219 // defined with a different type; show an appropriate diagnostic.
3221 // If the previous declaration was an implicitly-generated builtin
3222 // declaration, then at the very least we should use a specialized note.
3224 if (Old->isImplicit() && (BuiltinID = Old->getBuiltinID())) {
3225 // If it's actually a library-defined builtin function like 'malloc'
3226 // or 'printf', just warn about the incompatible redeclaration.
3227 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) {
3228 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New;
3229 Diag(OldLocation, diag::note_previous_builtin_declaration)
3230 << Old << Old->getType();
3232 // If this is a global redeclaration, just forget hereafter
3233 // about the "builtin-ness" of the function.
3235 // Doing this for local extern declarations is problematic. If
3236 // the builtin declaration remains visible, a second invalid
3237 // local declaration will produce a hard error; if it doesn't
3238 // remain visible, a single bogus local redeclaration (which is
3239 // actually only a warning) could break all the downstream code.
3240 if (!New->getLexicalDeclContext()->isFunctionOrMethod())
3241 New->getIdentifier()->revertBuiltin();
3246 PrevDiag = diag::note_previous_builtin_declaration;
3249 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName();
3250 Diag(OldLocation, PrevDiag) << Old << Old->getType();
3254 /// \brief Completes the merge of two function declarations that are
3255 /// known to be compatible.
3257 /// This routine handles the merging of attributes and other
3258 /// properties of function declarations from the old declaration to
3259 /// the new declaration, once we know that New is in fact a
3260 /// redeclaration of Old.
3263 bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old,
3264 Scope *S, bool MergeTypeWithOld) {
3265 // Merge the attributes
3266 mergeDeclAttributes(New, Old);
3268 // Merge "pure" flag.
3272 // Merge "used" flag.
3273 if (Old->getMostRecentDecl()->isUsed(false))
3276 // Merge attributes from the parameters. These can mismatch with K&R
3278 if (New->getNumParams() == Old->getNumParams())
3279 for (unsigned i = 0, e = New->getNumParams(); i != e; ++i) {
3280 ParmVarDecl *NewParam = New->getParamDecl(i);
3281 ParmVarDecl *OldParam = Old->getParamDecl(i);
3282 mergeParamDeclAttributes(NewParam, OldParam, *this);
3283 mergeParamDeclTypes(NewParam, OldParam, *this);
3286 if (getLangOpts().CPlusPlus)
3287 return MergeCXXFunctionDecl(New, Old, S);
3289 // Merge the function types so the we get the composite types for the return
3290 // and argument types. Per C11 6.2.7/4, only update the type if the old decl
3292 QualType Merged = Context.mergeTypes(Old->getType(), New->getType());
3293 if (!Merged.isNull() && MergeTypeWithOld)
3294 New->setType(Merged);
3299 void Sema::mergeObjCMethodDecls(ObjCMethodDecl *newMethod,
3300 ObjCMethodDecl *oldMethod) {
3301 // Merge the attributes, including deprecated/unavailable
3302 AvailabilityMergeKind MergeKind =
3303 isa<ObjCProtocolDecl>(oldMethod->getDeclContext())
3304 ? AMK_ProtocolImplementation
3305 : isa<ObjCImplDecl>(newMethod->getDeclContext()) ? AMK_Redeclaration
3308 mergeDeclAttributes(newMethod, oldMethod, MergeKind);
3310 // Merge attributes from the parameters.
3311 ObjCMethodDecl::param_const_iterator oi = oldMethod->param_begin(),
3312 oe = oldMethod->param_end();
3313 for (ObjCMethodDecl::param_iterator
3314 ni = newMethod->param_begin(), ne = newMethod->param_end();
3315 ni != ne && oi != oe; ++ni, ++oi)
3316 mergeParamDeclAttributes(*ni, *oi, *this);
3318 CheckObjCMethodOverride(newMethod, oldMethod);
3321 static void diagnoseVarDeclTypeMismatch(Sema &S, VarDecl *New, VarDecl* Old) {
3322 assert(!S.Context.hasSameType(New->getType(), Old->getType()));
3324 S.Diag(New->getLocation(), New->isThisDeclarationADefinition()
3325 ? diag::err_redefinition_different_type
3326 : diag::err_redeclaration_different_type)
3327 << New->getDeclName() << New->getType() << Old->getType();
3329 diag::kind PrevDiag;
3330 SourceLocation OldLocation;
3331 std::tie(PrevDiag, OldLocation)
3332 = getNoteDiagForInvalidRedeclaration(Old, New);
3333 S.Diag(OldLocation, PrevDiag);
3334 New->setInvalidDecl();
3337 /// MergeVarDeclTypes - We parsed a variable 'New' which has the same name and
3338 /// scope as a previous declaration 'Old'. Figure out how to merge their types,
3339 /// emitting diagnostics as appropriate.
3341 /// Declarations using the auto type specifier (C++ [decl.spec.auto]) call back
3342 /// to here in AddInitializerToDecl. We can't check them before the initializer
3344 void Sema::MergeVarDeclTypes(VarDecl *New, VarDecl *Old,
3345 bool MergeTypeWithOld) {
3346 if (New->isInvalidDecl() || Old->isInvalidDecl())
3350 if (getLangOpts().CPlusPlus) {
3351 if (New->getType()->isUndeducedType()) {
3352 // We don't know what the new type is until the initializer is attached.
3354 } else if (Context.hasSameType(New->getType(), Old->getType())) {
3355 // These could still be something that needs exception specs checked.
3356 return MergeVarDeclExceptionSpecs(New, Old);
3358 // C++ [basic.link]p10:
3359 // [...] the types specified by all declarations referring to a given
3360 // object or function shall be identical, except that declarations for an
3361 // array object can specify array types that differ by the presence or
3362 // absence of a major array bound (8.3.4).
3363 else if (Old->getType()->isArrayType() && New->getType()->isArrayType()) {
3364 const ArrayType *OldArray = Context.getAsArrayType(Old->getType());
3365 const ArrayType *NewArray = Context.getAsArrayType(New->getType());
3367 // We are merging a variable declaration New into Old. If it has an array
3368 // bound, and that bound differs from Old's bound, we should diagnose the
3370 if (!NewArray->isIncompleteArrayType()) {
3371 for (VarDecl *PrevVD = Old->getMostRecentDecl(); PrevVD;
3372 PrevVD = PrevVD->getPreviousDecl()) {
3373 const ArrayType *PrevVDTy = Context.getAsArrayType(PrevVD->getType());
3374 if (PrevVDTy->isIncompleteArrayType())
3377 if (!Context.hasSameType(NewArray, PrevVDTy))
3378 return diagnoseVarDeclTypeMismatch(*this, New, PrevVD);
3382 if (OldArray->isIncompleteArrayType() && NewArray->isArrayType()) {
3383 if (Context.hasSameType(OldArray->getElementType(),
3384 NewArray->getElementType()))
3385 MergedT = New->getType();
3387 // FIXME: Check visibility. New is hidden but has a complete type. If New
3388 // has no array bound, it should not inherit one from Old, if Old is not
3390 else if (OldArray->isArrayType() && NewArray->isIncompleteArrayType()) {
3391 if (Context.hasSameType(OldArray->getElementType(),
3392 NewArray->getElementType()))
3393 MergedT = Old->getType();
3396 else if (New->getType()->isObjCObjectPointerType() &&
3397 Old->getType()->isObjCObjectPointerType()) {
3398 MergedT = Context.mergeObjCGCQualifiers(New->getType(),
3403 // All declarations that refer to the same object or function shall have
3405 MergedT = Context.mergeTypes(New->getType(), Old->getType());
3407 if (MergedT.isNull()) {
3408 // It's OK if we couldn't merge types if either type is dependent, for a
3409 // block-scope variable. In other cases (static data members of class
3410 // templates, variable templates, ...), we require the types to be
3412 // FIXME: The C++ standard doesn't say anything about this.
3413 if ((New->getType()->isDependentType() ||
3414 Old->getType()->isDependentType()) && New->isLocalVarDecl()) {
3415 // If the old type was dependent, we can't merge with it, so the new type
3416 // becomes dependent for now. We'll reproduce the original type when we
3417 // instantiate the TypeSourceInfo for the variable.
3418 if (!New->getType()->isDependentType() && MergeTypeWithOld)
3419 New->setType(Context.DependentTy);
3422 return diagnoseVarDeclTypeMismatch(*this, New, Old);
3425 // Don't actually update the type on the new declaration if the old
3426 // declaration was an extern declaration in a different scope.
3427 if (MergeTypeWithOld)
3428 New->setType(MergedT);
3431 static bool mergeTypeWithPrevious(Sema &S, VarDecl *NewVD, VarDecl *OldVD,
3432 LookupResult &Previous) {
3434 // For an identifier with internal or external linkage declared
3435 // in a scope in which a prior declaration of that identifier is
3436 // visible, if the prior declaration specifies internal or
3437 // external linkage, the type of the identifier at the later
3438 // declaration becomes the composite type.
3440 // If the variable isn't visible, we do not merge with its type.
3441 if (Previous.isShadowed())
3444 if (S.getLangOpts().CPlusPlus) {
3445 // C++11 [dcl.array]p3:
3446 // If there is a preceding declaration of the entity in the same
3447 // scope in which the bound was specified, an omitted array bound
3448 // is taken to be the same as in that earlier declaration.
3449 return NewVD->isPreviousDeclInSameBlockScope() ||
3450 (!OldVD->getLexicalDeclContext()->isFunctionOrMethod() &&
3451 !NewVD->getLexicalDeclContext()->isFunctionOrMethod());
3453 // If the old declaration was function-local, don't merge with its
3454 // type unless we're in the same function.
3455 return !OldVD->getLexicalDeclContext()->isFunctionOrMethod() ||
3456 OldVD->getLexicalDeclContext() == NewVD->getLexicalDeclContext();
3460 /// MergeVarDecl - We just parsed a variable 'New' which has the same name
3461 /// and scope as a previous declaration 'Old'. Figure out how to resolve this
3462 /// situation, merging decls or emitting diagnostics as appropriate.
3464 /// Tentative definition rules (C99 6.9.2p2) are checked by
3465 /// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative
3466 /// definitions here, since the initializer hasn't been attached.
3468 void Sema::MergeVarDecl(VarDecl *New, LookupResult &Previous) {
3469 // If the new decl is already invalid, don't do any other checking.
3470 if (New->isInvalidDecl())
3473 if (!shouldLinkPossiblyHiddenDecl(Previous, New))
3476 VarTemplateDecl *NewTemplate = New->getDescribedVarTemplate();
3478 // Verify the old decl was also a variable or variable template.
3479 VarDecl *Old = nullptr;
3480 VarTemplateDecl *OldTemplate = nullptr;
3481 if (Previous.isSingleResult()) {
3483 OldTemplate = dyn_cast<VarTemplateDecl>(Previous.getFoundDecl());
3484 Old = OldTemplate ? OldTemplate->getTemplatedDecl() : nullptr;
3487 dyn_cast<UsingShadowDecl>(Previous.getRepresentativeDecl()))
3488 if (checkUsingShadowRedecl<VarTemplateDecl>(*this, Shadow, NewTemplate))
3489 return New->setInvalidDecl();
3491 Old = dyn_cast<VarDecl>(Previous.getFoundDecl());
3494 dyn_cast<UsingShadowDecl>(Previous.getRepresentativeDecl()))
3495 if (checkUsingShadowRedecl<VarDecl>(*this, Shadow, New))
3496 return New->setInvalidDecl();
3500 Diag(New->getLocation(), diag::err_redefinition_different_kind)
3501 << New->getDeclName();
3502 Diag(Previous.getRepresentativeDecl()->getLocation(),
3503 diag::note_previous_definition);
3504 return New->setInvalidDecl();
3507 // Ensure the template parameters are compatible.
3509 !TemplateParameterListsAreEqual(NewTemplate->getTemplateParameters(),
3510 OldTemplate->getTemplateParameters(),
3511 /*Complain=*/true, TPL_TemplateMatch))
3512 return New->setInvalidDecl();
3514 // C++ [class.mem]p1:
3515 // A member shall not be declared twice in the member-specification [...]
3517 // Here, we need only consider static data members.
3518 if (Old->isStaticDataMember() && !New->isOutOfLine()) {
3519 Diag(New->getLocation(), diag::err_duplicate_member)
3520 << New->getIdentifier();
3521 Diag(Old->getLocation(), diag::note_previous_declaration);
3522 New->setInvalidDecl();
3525 mergeDeclAttributes(New, Old);
3526 // Warn if an already-declared variable is made a weak_import in a subsequent
3528 if (New->hasAttr<WeakImportAttr>() &&
3529 Old->getStorageClass() == SC_None &&
3530 !Old->hasAttr<WeakImportAttr>()) {
3531 Diag(New->getLocation(), diag::warn_weak_import) << New->getDeclName();
3532 Diag(Old->getLocation(), diag::note_previous_definition);
3533 // Remove weak_import attribute on new declaration.
3534 New->dropAttr<WeakImportAttr>();
3537 if (New->hasAttr<InternalLinkageAttr>() &&
3538 !Old->hasAttr<InternalLinkageAttr>()) {
3539 Diag(New->getLocation(), diag::err_internal_linkage_redeclaration)
3540 << New->getDeclName();
3541 Diag(Old->getLocation(), diag::note_previous_definition);
3542 New->dropAttr<InternalLinkageAttr>();
3546 VarDecl *MostRecent = Old->getMostRecentDecl();
3547 if (MostRecent != Old) {
3548 MergeVarDeclTypes(New, MostRecent,
3549 mergeTypeWithPrevious(*this, New, MostRecent, Previous));
3550 if (New->isInvalidDecl())
3554 MergeVarDeclTypes(New, Old, mergeTypeWithPrevious(*this, New, Old, Previous));
3555 if (New->isInvalidDecl())
3558 diag::kind PrevDiag;
3559 SourceLocation OldLocation;
3560 std::tie(PrevDiag, OldLocation) =
3561 getNoteDiagForInvalidRedeclaration(Old, New);
3563 // [dcl.stc]p8: Check if we have a non-static decl followed by a static.
3564 if (New->getStorageClass() == SC_Static &&
3565 !New->isStaticDataMember() &&
3566 Old->hasExternalFormalLinkage()) {
3567 if (getLangOpts().MicrosoftExt) {
3568 Diag(New->getLocation(), diag::ext_static_non_static)
3569 << New->getDeclName();
3570 Diag(OldLocation, PrevDiag);
3572 Diag(New->getLocation(), diag::err_static_non_static)
3573 << New->getDeclName();
3574 Diag(OldLocation, PrevDiag);
3575 return New->setInvalidDecl();
3579 // For an identifier declared with the storage-class specifier
3580 // extern in a scope in which a prior declaration of that
3581 // identifier is visible,23) if the prior declaration specifies
3582 // internal or external linkage, the linkage of the identifier at
3583 // the later declaration is the same as the linkage specified at
3584 // the prior declaration. If no prior declaration is visible, or
3585 // if the prior declaration specifies no linkage, then the
3586 // identifier has external linkage.
3587 if (New->hasExternalStorage() && Old->hasLinkage())
3589 else if (New->getCanonicalDecl()->getStorageClass() != SC_Static &&
3590 !New->isStaticDataMember() &&
3591 Old->getCanonicalDecl()->getStorageClass() == SC_Static) {
3592 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName();
3593 Diag(OldLocation, PrevDiag);
3594 return New->setInvalidDecl();
3597 // Check if extern is followed by non-extern and vice-versa.
3598 if (New->hasExternalStorage() &&
3599 !Old->hasLinkage() && Old->isLocalVarDeclOrParm()) {
3600 Diag(New->getLocation(), diag::err_extern_non_extern) << New->getDeclName();
3601 Diag(OldLocation, PrevDiag);
3602 return New->setInvalidDecl();
3604 if (Old->hasLinkage() && New->isLocalVarDeclOrParm() &&
3605 !New->hasExternalStorage()) {
3606 Diag(New->getLocation(), diag::err_non_extern_extern) << New->getDeclName();
3607 Diag(OldLocation, PrevDiag);
3608 return New->setInvalidDecl();
3611 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup.
3613 // FIXME: The test for external storage here seems wrong? We still
3614 // need to check for mismatches.
3615 if (!New->hasExternalStorage() && !New->isFileVarDecl() &&
3616 // Don't complain about out-of-line definitions of static members.
3617 !(Old->getLexicalDeclContext()->isRecord() &&
3618 !New->getLexicalDeclContext()->isRecord())) {
3619 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName();
3620 Diag(OldLocation, PrevDiag);
3621 return New->setInvalidDecl();
3624 if (New->isInline() && !Old->getMostRecentDecl()->isInline()) {
3625 if (VarDecl *Def = Old->getDefinition()) {
3626 // C++1z [dcl.fcn.spec]p4:
3627 // If the definition of a variable appears in a translation unit before
3628 // its first declaration as inline, the program is ill-formed.
3629 Diag(New->getLocation(), diag::err_inline_decl_follows_def) << New;
3630 Diag(Def->getLocation(), diag::note_previous_definition);
3634 // If this redeclaration makes the function inline, we may need to add it to
3635 // UndefinedButUsed.
3636 if (!Old->isInline() && New->isInline() && Old->isUsed(false) &&
3637 !Old->getDefinition() && !New->isThisDeclarationADefinition())
3638 UndefinedButUsed.insert(std::make_pair(Old->getCanonicalDecl(),
3641 if (New->getTLSKind() != Old->getTLSKind()) {
3642 if (!Old->getTLSKind()) {
3643 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName();
3644 Diag(OldLocation, PrevDiag);
3645 } else if (!New->getTLSKind()) {
3646 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName();
3647 Diag(OldLocation, PrevDiag);
3649 // Do not allow redeclaration to change the variable between requiring
3650 // static and dynamic initialization.
3651 // FIXME: GCC allows this, but uses the TLS keyword on the first
3652 // declaration to determine the kind. Do we need to be compatible here?
3653 Diag(New->getLocation(), diag::err_thread_thread_different_kind)
3654 << New->getDeclName() << (New->getTLSKind() == VarDecl::TLS_Dynamic);
3655 Diag(OldLocation, PrevDiag);
3659 // C++ doesn't have tentative definitions, so go right ahead and check here.
3661 if (getLangOpts().CPlusPlus &&
3662 New->isThisDeclarationADefinition() == VarDecl::Definition &&
3663 (Def = Old->getDefinition())) {
3664 NamedDecl *Hidden = nullptr;
3665 if (!hasVisibleDefinition(Def, &Hidden) &&
3666 (New->getFormalLinkage() == InternalLinkage ||
3667 New->getDescribedVarTemplate() ||
3668 New->getNumTemplateParameterLists() ||
3669 New->getDeclContext()->isDependentContext())) {
3670 // The previous definition is hidden, and multiple definitions are
3671 // permitted (in separate TUs). Form another definition of it.
3672 } else if (Old->isStaticDataMember() &&
3673 Old->getCanonicalDecl()->isInline() &&
3674 Old->getCanonicalDecl()->isConstexpr()) {
3675 // This definition won't be a definition any more once it's been merged.
3676 Diag(New->getLocation(),
3677 diag::warn_deprecated_redundant_constexpr_static_def);
3679 Diag(New->getLocation(), diag::err_redefinition) << New;
3680 Diag(Def->getLocation(), diag::note_previous_definition);
3681 New->setInvalidDecl();
3686 if (haveIncompatibleLanguageLinkages(Old, New)) {
3687 Diag(New->getLocation(), diag::err_different_language_linkage) << New;
3688 Diag(OldLocation, PrevDiag);
3689 New->setInvalidDecl();
3693 // Merge "used" flag.
3694 if (Old->getMostRecentDecl()->isUsed(false))
3697 // Keep a chain of previous declarations.
3698 New->setPreviousDecl(Old);
3700 NewTemplate->setPreviousDecl(OldTemplate);
3702 // Inherit access appropriately.
3703 New->setAccess(Old->getAccess());
3705 NewTemplate->setAccess(New->getAccess());
3707 if (Old->isInline())
3708 New->setImplicitlyInline();
3711 /// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with
3712 /// no declarator (e.g. "struct foo;") is parsed.
3714 Sema::ParsedFreeStandingDeclSpec(Scope *S, AccessSpecifier AS, DeclSpec &DS,
3715 RecordDecl *&AnonRecord) {
3716 return ParsedFreeStandingDeclSpec(S, AS, DS, MultiTemplateParamsArg(), false,
3720 // The MS ABI changed between VS2013 and VS2015 with regard to numbers used to
3721 // disambiguate entities defined in different scopes.
3722 // While the VS2015 ABI fixes potential miscompiles, it is also breaks
3724 // We will pick our mangling number depending on which version of MSVC is being
3726 static unsigned getMSManglingNumber(const LangOptions &LO, Scope *S) {
3727 return LO.isCompatibleWithMSVC(LangOptions::MSVC2015)
3728 ? S->getMSCurManglingNumber()
3729 : S->getMSLastManglingNumber();
3732 void Sema::handleTagNumbering(const TagDecl *Tag, Scope *TagScope) {
3733 if (!Context.getLangOpts().CPlusPlus)
3736 if (isa<CXXRecordDecl>(Tag->getParent())) {
3737 // If this tag is the direct child of a class, number it if
3739 if (!Tag->getName().empty() || Tag->getTypedefNameForAnonDecl())
3741 MangleNumberingContext &MCtx =
3742 Context.getManglingNumberContext(Tag->getParent());
3743 Context.setManglingNumber(
3744 Tag, MCtx.getManglingNumber(
3745 Tag, getMSManglingNumber(getLangOpts(), TagScope)));
3749 // If this tag isn't a direct child of a class, number it if it is local.
3750 Decl *ManglingContextDecl;
3751 if (MangleNumberingContext *MCtx = getCurrentMangleNumberContext(
3752 Tag->getDeclContext(), ManglingContextDecl)) {
3753 Context.setManglingNumber(
3754 Tag, MCtx->getManglingNumber(
3755 Tag, getMSManglingNumber(getLangOpts(), TagScope)));
3759 void Sema::setTagNameForLinkagePurposes(TagDecl *TagFromDeclSpec,
3760 TypedefNameDecl *NewTD) {
3761 if (TagFromDeclSpec->isInvalidDecl())
3764 // Do nothing if the tag already has a name for linkage purposes.
3765 if (TagFromDeclSpec->hasNameForLinkage())
3768 // A well-formed anonymous tag must always be a TUK_Definition.
3769 assert(TagFromDeclSpec->isThisDeclarationADefinition());
3771 // The type must match the tag exactly; no qualifiers allowed.
3772 if (!Context.hasSameType(NewTD->getUnderlyingType(),
3773 Context.getTagDeclType(TagFromDeclSpec))) {
3774 if (getLangOpts().CPlusPlus)
3775 Context.addTypedefNameForUnnamedTagDecl(TagFromDeclSpec, NewTD);
3779 // If we've already computed linkage for the anonymous tag, then
3780 // adding a typedef name for the anonymous decl can change that
3781 // linkage, which might be a serious problem. Diagnose this as
3782 // unsupported and ignore the typedef name. TODO: we should
3783 // pursue this as a language defect and establish a formal rule
3784 // for how to handle it.
3785 if (TagFromDeclSpec->hasLinkageBeenComputed()) {
3786 Diag(NewTD->getLocation(), diag::err_typedef_changes_linkage);
3788 SourceLocation tagLoc = TagFromDeclSpec->getInnerLocStart();
3789 tagLoc = getLocForEndOfToken(tagLoc);
3791 llvm::SmallString<40> textToInsert;
3792 textToInsert += ' ';
3793 textToInsert += NewTD->getIdentifier()->getName();
3794 Diag(tagLoc, diag::note_typedef_changes_linkage)
3795 << FixItHint::CreateInsertion(tagLoc, textToInsert);
3799 // Otherwise, set this is the anon-decl typedef for the tag.
3800 TagFromDeclSpec->setTypedefNameForAnonDecl(NewTD);
3803 static unsigned GetDiagnosticTypeSpecifierID(DeclSpec::TST T) {
3805 case DeclSpec::TST_class:
3807 case DeclSpec::TST_struct:
3809 case DeclSpec::TST_interface:
3811 case DeclSpec::TST_union:
3813 case DeclSpec::TST_enum:
3816 llvm_unreachable("unexpected type specifier");
3820 /// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with
3821 /// no declarator (e.g. "struct foo;") is parsed. It also accepts template
3822 /// parameters to cope with template friend declarations.
3824 Sema::ParsedFreeStandingDeclSpec(Scope *S, AccessSpecifier AS, DeclSpec &DS,
3825 MultiTemplateParamsArg TemplateParams,
3826 bool IsExplicitInstantiation,
3827 RecordDecl *&AnonRecord) {
3828 Decl *TagD = nullptr;
3829 TagDecl *Tag = nullptr;
3830 if (DS.getTypeSpecType() == DeclSpec::TST_class ||
3831 DS.getTypeSpecType() == DeclSpec::TST_struct ||
3832 DS.getTypeSpecType() == DeclSpec::TST_interface ||
3833 DS.getTypeSpecType() == DeclSpec::TST_union ||
3834 DS.getTypeSpecType() == DeclSpec::TST_enum) {
3835 TagD = DS.getRepAsDecl();
3837 if (!TagD) // We probably had an error
3840 // Note that the above type specs guarantee that the
3841 // type rep is a Decl, whereas in many of the others
3843 if (isa<TagDecl>(TagD))
3844 Tag = cast<TagDecl>(TagD);
3845 else if (ClassTemplateDecl *CTD = dyn_cast<ClassTemplateDecl>(TagD))
3846 Tag = CTD->getTemplatedDecl();
3850 handleTagNumbering(Tag, S);
3851 Tag->setFreeStanding();
3852 if (Tag->isInvalidDecl())
3856 if (unsigned TypeQuals = DS.getTypeQualifiers()) {
3857 // Enforce C99 6.7.3p2: "Types other than pointer types derived from object
3858 // or incomplete types shall not be restrict-qualified."
3859 if (TypeQuals & DeclSpec::TQ_restrict)
3860 Diag(DS.getRestrictSpecLoc(),
3861 diag::err_typecheck_invalid_restrict_not_pointer_noarg)
3862 << DS.getSourceRange();
3865 if (DS.isInlineSpecified())
3866 Diag(DS.getInlineSpecLoc(), diag::err_inline_non_function)
3867 << getLangOpts().CPlusPlus1z;
3869 if (DS.isConstexprSpecified()) {
3870 // C++0x [dcl.constexpr]p1: constexpr can only be applied to declarations
3871 // and definitions of functions and variables.
3873 Diag(DS.getConstexprSpecLoc(), diag::err_constexpr_tag)
3874 << GetDiagnosticTypeSpecifierID(DS.getTypeSpecType());
3876 Diag(DS.getConstexprSpecLoc(), diag::err_constexpr_no_declarators);
3877 // Don't emit warnings after this error.
3881 if (DS.isConceptSpecified()) {
3882 // C++ Concepts TS [dcl.spec.concept]p1: A concept definition refers to
3883 // either a function concept and its definition or a variable concept and
3885 Diag(DS.getConceptSpecLoc(), diag::err_concept_wrong_decl_kind);
3889 DiagnoseFunctionSpecifiers(DS);
3891 if (DS.isFriendSpecified()) {
3892 // If we're dealing with a decl but not a TagDecl, assume that
3893 // whatever routines created it handled the friendship aspect.
3896 return ActOnFriendTypeDecl(S, DS, TemplateParams);
3899 const CXXScopeSpec &SS = DS.getTypeSpecScope();
3900 bool IsExplicitSpecialization =
3901 !TemplateParams.empty() && TemplateParams.back()->size() == 0;
3902 if (Tag && SS.isNotEmpty() && !Tag->isCompleteDefinition() &&
3903 !IsExplicitInstantiation && !IsExplicitSpecialization &&
3904 !isa<ClassTemplatePartialSpecializationDecl>(Tag)) {
3905 // Per C++ [dcl.type.elab]p1, a class declaration cannot have a
3906 // nested-name-specifier unless it is an explicit instantiation
3907 // or an explicit specialization.
3909 // FIXME: We allow class template partial specializations here too, per the
3910 // obvious intent of DR1819.
3912 // Per C++ [dcl.enum]p1, an opaque-enum-declaration can't either.
3913 Diag(SS.getBeginLoc(), diag::err_standalone_class_nested_name_specifier)
3914 << GetDiagnosticTypeSpecifierID(DS.getTypeSpecType()) << SS.getRange();
3918 // Track whether this decl-specifier declares anything.
3919 bool DeclaresAnything = true;
3921 // Handle anonymous struct definitions.
3922 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) {
3923 if (!Record->getDeclName() && Record->isCompleteDefinition() &&
3924 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) {
3925 if (getLangOpts().CPlusPlus ||
3926 Record->getDeclContext()->isRecord()) {
3927 // If CurContext is a DeclContext that can contain statements,
3928 // RecursiveASTVisitor won't visit the decls that
3929 // BuildAnonymousStructOrUnion() will put into CurContext.
3930 // Also store them here so that they can be part of the
3931 // DeclStmt that gets created in this case.
3932 // FIXME: Also return the IndirectFieldDecls created by
3933 // BuildAnonymousStructOr union, for the same reason?
3934 if (CurContext->isFunctionOrMethod())
3935 AnonRecord = Record;
3936 return BuildAnonymousStructOrUnion(S, DS, AS, Record,
3937 Context.getPrintingPolicy());
3940 DeclaresAnything = false;
3945 // A struct-declaration that does not declare an anonymous structure or
3946 // anonymous union shall contain a struct-declarator-list.
3948 // This rule also existed in C89 and C99; the grammar for struct-declaration
3949 // did not permit a struct-declaration without a struct-declarator-list.
3950 if (!getLangOpts().CPlusPlus && CurContext->isRecord() &&
3951 DS.getStorageClassSpec() == DeclSpec::SCS_unspecified) {
3952 // Check for Microsoft C extension: anonymous struct/union member.
3953 // Handle 2 kinds of anonymous struct/union:
3957 // STRUCT_TYPE; <- where STRUCT_TYPE is a typedef struct.
3958 // UNION_TYPE; <- where UNION_TYPE is a typedef union.
3959 if ((Tag && Tag->getDeclName()) ||
3960 DS.getTypeSpecType() == DeclSpec::TST_typename) {
3961 RecordDecl *Record = nullptr;
3963 Record = dyn_cast<RecordDecl>(Tag);
3964 else if (const RecordType *RT =
3965 DS.getRepAsType().get()->getAsStructureType())
3966 Record = RT->getDecl();
3967 else if (const RecordType *UT = DS.getRepAsType().get()->getAsUnionType())
3968 Record = UT->getDecl();
3970 if (Record && getLangOpts().MicrosoftExt) {
3971 Diag(DS.getLocStart(), diag::ext_ms_anonymous_record)
3972 << Record->isUnion() << DS.getSourceRange();
3973 return BuildMicrosoftCAnonymousStruct(S, DS, Record);
3976 DeclaresAnything = false;
3980 // Skip all the checks below if we have a type error.
3981 if (DS.getTypeSpecType() == DeclSpec::TST_error ||
3982 (TagD && TagD->isInvalidDecl()))
3985 if (getLangOpts().CPlusPlus &&
3986 DS.getStorageClassSpec() != DeclSpec::SCS_typedef)
3987 if (EnumDecl *Enum = dyn_cast_or_null<EnumDecl>(Tag))
3988 if (Enum->enumerator_begin() == Enum->enumerator_end() &&
3989 !Enum->getIdentifier() && !Enum->isInvalidDecl())
3990 DeclaresAnything = false;
3992 if (!DS.isMissingDeclaratorOk()) {
3993 // Customize diagnostic for a typedef missing a name.
3994 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef)
3995 Diag(DS.getLocStart(), diag::ext_typedef_without_a_name)
3996 << DS.getSourceRange();
3998 DeclaresAnything = false;
4001 if (DS.isModulePrivateSpecified() &&
4002 Tag && Tag->getDeclContext()->isFunctionOrMethod())
4003 Diag(DS.getModulePrivateSpecLoc(), diag::err_module_private_local_class)
4004 << Tag->getTagKind()
4005 << FixItHint::CreateRemoval(DS.getModulePrivateSpecLoc());
4007 ActOnDocumentableDecl(TagD);
4010 // A declaration [...] shall declare at least a declarator [...], a tag,
4011 // or the members of an enumeration.
4013 // [If there are no declarators], and except for the declaration of an
4014 // unnamed bit-field, the decl-specifier-seq shall introduce one or more
4015 // names into the program, or shall redeclare a name introduced by a
4016 // previous declaration.
4017 if (!DeclaresAnything) {
4018 // In C, we allow this as a (popular) extension / bug. Don't bother
4019 // producing further diagnostics for redundant qualifiers after this.
4020 Diag(DS.getLocStart(), diag::ext_no_declarators) << DS.getSourceRange();
4025 // If a storage-class-specifier appears in a decl-specifier-seq, [...] the
4026 // init-declarator-list of the declaration shall not be empty.
4027 // C++ [dcl.fct.spec]p1:
4028 // If a cv-qualifier appears in a decl-specifier-seq, the
4029 // init-declarator-list of the declaration shall not be empty.
4031 // Spurious qualifiers here appear to be valid in C.
4032 unsigned DiagID = diag::warn_standalone_specifier;
4033 if (getLangOpts().CPlusPlus)
4034 DiagID = diag::ext_standalone_specifier;
4036 // Note that a linkage-specification sets a storage class, but
4037 // 'extern "C" struct foo;' is actually valid and not theoretically
4039 if (DeclSpec::SCS SCS = DS.getStorageClassSpec()) {
4040 if (SCS == DeclSpec::SCS_mutable)
4041 // Since mutable is not a viable storage class specifier in C, there is
4042 // no reason to treat it as an extension. Instead, diagnose as an error.
4043 Diag(DS.getStorageClassSpecLoc(), diag::err_mutable_nonmember);
4044 else if (!DS.isExternInLinkageSpec() && SCS != DeclSpec::SCS_typedef)
4045 Diag(DS.getStorageClassSpecLoc(), DiagID)
4046 << DeclSpec::getSpecifierName(SCS);
4049 if (DeclSpec::TSCS TSCS = DS.getThreadStorageClassSpec())
4050 Diag(DS.getThreadStorageClassSpecLoc(), DiagID)
4051 << DeclSpec::getSpecifierName(TSCS);
4052 if (DS.getTypeQualifiers()) {
4053 if (DS.getTypeQualifiers() & DeclSpec::TQ_const)
4054 Diag(DS.getConstSpecLoc(), DiagID) << "const";
4055 if (DS.getTypeQualifiers() & DeclSpec::TQ_volatile)
4056 Diag(DS.getConstSpecLoc(), DiagID) << "volatile";
4057 // Restrict is covered above.
4058 if (DS.getTypeQualifiers() & DeclSpec::TQ_atomic)
4059 Diag(DS.getAtomicSpecLoc(), DiagID) << "_Atomic";
4060 if (DS.getTypeQualifiers() & DeclSpec::TQ_unaligned)
4061 Diag(DS.getUnalignedSpecLoc(), DiagID) << "__unaligned";
4064 // Warn about ignored type attributes, for example:
4065 // __attribute__((aligned)) struct A;
4066 // Attributes should be placed after tag to apply to type declaration.
4067 if (!DS.getAttributes().empty()) {
4068 DeclSpec::TST TypeSpecType = DS.getTypeSpecType();
4069 if (TypeSpecType == DeclSpec::TST_class ||
4070 TypeSpecType == DeclSpec::TST_struct ||
4071 TypeSpecType == DeclSpec::TST_interface ||
4072 TypeSpecType == DeclSpec::TST_union ||
4073 TypeSpecType == DeclSpec::TST_enum) {
4074 for (AttributeList* attrs = DS.getAttributes().getList(); attrs;
4075 attrs = attrs->getNext())
4076 Diag(attrs->getLoc(), diag::warn_declspec_attribute_ignored)
4077 << attrs->getName() << GetDiagnosticTypeSpecifierID(TypeSpecType);
4084 /// We are trying to inject an anonymous member into the given scope;
4085 /// check if there's an existing declaration that can't be overloaded.
4087 /// \return true if this is a forbidden redeclaration
4088 static bool CheckAnonMemberRedeclaration(Sema &SemaRef,
4091 DeclarationName Name,
4092 SourceLocation NameLoc,
4094 LookupResult R(SemaRef, Name, NameLoc, Sema::LookupMemberName,
4095 Sema::ForRedeclaration);
4096 if (!SemaRef.LookupName(R, S)) return false;
4098 // Pick a representative declaration.
4099 NamedDecl *PrevDecl = R.getRepresentativeDecl()->getUnderlyingDecl();
4100 assert(PrevDecl && "Expected a non-null Decl");
4102 if (!SemaRef.isDeclInScope(PrevDecl, Owner, S))
4105 SemaRef.Diag(NameLoc, diag::err_anonymous_record_member_redecl)
4107 SemaRef.Diag(PrevDecl->getLocation(), diag::note_previous_declaration);
4112 /// InjectAnonymousStructOrUnionMembers - Inject the members of the
4113 /// anonymous struct or union AnonRecord into the owning context Owner
4114 /// and scope S. This routine will be invoked just after we realize
4115 /// that an unnamed union or struct is actually an anonymous union or
4122 /// }; // InjectAnonymousStructOrUnionMembers called here to inject i and
4123 /// // f into the surrounding scope.x
4126 /// This routine is recursive, injecting the names of nested anonymous
4127 /// structs/unions into the owning context and scope as well.
4129 InjectAnonymousStructOrUnionMembers(Sema &SemaRef, Scope *S, DeclContext *Owner,
4130 RecordDecl *AnonRecord, AccessSpecifier AS,
4131 SmallVectorImpl<NamedDecl *> &Chaining) {
4132 bool Invalid = false;
4134 // Look every FieldDecl and IndirectFieldDecl with a name.
4135 for (auto *D : AnonRecord->decls()) {
4136 if ((isa<FieldDecl>(D) || isa<IndirectFieldDecl>(D)) &&
4137 cast<NamedDecl>(D)->getDeclName()) {
4138 ValueDecl *VD = cast<ValueDecl>(D);
4139 if (CheckAnonMemberRedeclaration(SemaRef, S, Owner, VD->getDeclName(),
4141 AnonRecord->isUnion())) {
4142 // C++ [class.union]p2:
4143 // The names of the members of an anonymous union shall be
4144 // distinct from the names of any other entity in the
4145 // scope in which the anonymous union is declared.
4148 // C++ [class.union]p2:
4149 // For the purpose of name lookup, after the anonymous union
4150 // definition, the members of the anonymous union are
4151 // considered to have been defined in the scope in which the
4152 // anonymous union is declared.
4153 unsigned OldChainingSize = Chaining.size();
4154 if (IndirectFieldDecl *IF = dyn_cast<IndirectFieldDecl>(VD))
4155 Chaining.append(IF->chain_begin(), IF->chain_end());
4157 Chaining.push_back(VD);
4159 assert(Chaining.size() >= 2);
4160 NamedDecl **NamedChain =
4161 new (SemaRef.Context)NamedDecl*[Chaining.size()];
4162 for (unsigned i = 0; i < Chaining.size(); i++)
4163 NamedChain[i] = Chaining[i];
4165 IndirectFieldDecl *IndirectField = IndirectFieldDecl::Create(
4166 SemaRef.Context, Owner, VD->getLocation(), VD->getIdentifier(),
4167 VD->getType(), {NamedChain, Chaining.size()});
4169 for (const auto *Attr : VD->attrs())
4170 IndirectField->addAttr(Attr->clone(SemaRef.Context));
4172 IndirectField->setAccess(AS);
4173 IndirectField->setImplicit();
4174 SemaRef.PushOnScopeChains(IndirectField, S);
4176 // That includes picking up the appropriate access specifier.
4177 if (AS != AS_none) IndirectField->setAccess(AS);
4179 Chaining.resize(OldChainingSize);
4187 /// StorageClassSpecToVarDeclStorageClass - Maps a DeclSpec::SCS to
4188 /// a VarDecl::StorageClass. Any error reporting is up to the caller:
4189 /// illegal input values are mapped to SC_None.
4191 StorageClassSpecToVarDeclStorageClass(const DeclSpec &DS) {
4192 DeclSpec::SCS StorageClassSpec = DS.getStorageClassSpec();
4193 assert(StorageClassSpec != DeclSpec::SCS_typedef &&
4194 "Parser allowed 'typedef' as storage class VarDecl.");
4195 switch (StorageClassSpec) {
4196 case DeclSpec::SCS_unspecified: return SC_None;
4197 case DeclSpec::SCS_extern:
4198 if (DS.isExternInLinkageSpec())
4201 case DeclSpec::SCS_static: return SC_Static;
4202 case DeclSpec::SCS_auto: return SC_Auto;
4203 case DeclSpec::SCS_register: return SC_Register;
4204 case DeclSpec::SCS_private_extern: return SC_PrivateExtern;
4205 // Illegal SCSs map to None: error reporting is up to the caller.
4206 case DeclSpec::SCS_mutable: // Fall through.
4207 case DeclSpec::SCS_typedef: return SC_None;
4209 llvm_unreachable("unknown storage class specifier");
4212 static SourceLocation findDefaultInitializer(const CXXRecordDecl *Record) {
4213 assert(Record->hasInClassInitializer());
4215 for (const auto *I : Record->decls()) {
4216 const auto *FD = dyn_cast<FieldDecl>(I);
4217 if (const auto *IFD = dyn_cast<IndirectFieldDecl>(I))
4218 FD = IFD->getAnonField();
4219 if (FD && FD->hasInClassInitializer())
4220 return FD->getLocation();
4223 llvm_unreachable("couldn't find in-class initializer");
4226 static void checkDuplicateDefaultInit(Sema &S, CXXRecordDecl *Parent,
4227 SourceLocation DefaultInitLoc) {
4228 if (!Parent->isUnion() || !Parent->hasInClassInitializer())
4231 S.Diag(DefaultInitLoc, diag::err_multiple_mem_union_initialization);
4232 S.Diag(findDefaultInitializer(Parent), diag::note_previous_initializer) << 0;
4235 static void checkDuplicateDefaultInit(Sema &S, CXXRecordDecl *Parent,
4236 CXXRecordDecl *AnonUnion) {
4237 if (!Parent->isUnion() || !Parent->hasInClassInitializer())
4240 checkDuplicateDefaultInit(S, Parent, findDefaultInitializer(AnonUnion));
4243 /// BuildAnonymousStructOrUnion - Handle the declaration of an
4244 /// anonymous structure or union. Anonymous unions are a C++ feature
4245 /// (C++ [class.union]) and a C11 feature; anonymous structures
4246 /// are a C11 feature and GNU C++ extension.
4247 Decl *Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS,
4250 const PrintingPolicy &Policy) {
4251 DeclContext *Owner = Record->getDeclContext();
4253 // Diagnose whether this anonymous struct/union is an extension.
4254 if (Record->isUnion() && !getLangOpts().CPlusPlus && !getLangOpts().C11)
4255 Diag(Record->getLocation(), diag::ext_anonymous_union);
4256 else if (!Record->isUnion() && getLangOpts().CPlusPlus)
4257 Diag(Record->getLocation(), diag::ext_gnu_anonymous_struct);
4258 else if (!Record->isUnion() && !getLangOpts().C11)
4259 Diag(Record->getLocation(), diag::ext_c11_anonymous_struct);
4261 // C and C++ require different kinds of checks for anonymous
4263 bool Invalid = false;
4264 if (getLangOpts().CPlusPlus) {
4265 const char *PrevSpec = nullptr;
4267 if (Record->isUnion()) {
4268 // C++ [class.union]p6:
4269 // Anonymous unions declared in a named namespace or in the
4270 // global namespace shall be declared static.
4271 if (DS.getStorageClassSpec() != DeclSpec::SCS_static &&
4272 (isa<TranslationUnitDecl>(Owner) ||
4273 (isa<NamespaceDecl>(Owner) &&
4274 cast<NamespaceDecl>(Owner)->getDeclName()))) {
4275 Diag(Record->getLocation(), diag::err_anonymous_union_not_static)
4276 << FixItHint::CreateInsertion(Record->getLocation(), "static ");
4278 // Recover by adding 'static'.
4279 DS.SetStorageClassSpec(*this, DeclSpec::SCS_static, SourceLocation(),
4280 PrevSpec, DiagID, Policy);
4282 // C++ [class.union]p6:
4283 // A storage class is not allowed in a declaration of an
4284 // anonymous union in a class scope.
4285 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified &&
4286 isa<RecordDecl>(Owner)) {
4287 Diag(DS.getStorageClassSpecLoc(),
4288 diag::err_anonymous_union_with_storage_spec)
4289 << FixItHint::CreateRemoval(DS.getStorageClassSpecLoc());
4291 // Recover by removing the storage specifier.
4292 DS.SetStorageClassSpec(*this, DeclSpec::SCS_unspecified,
4294 PrevSpec, DiagID, Context.getPrintingPolicy());
4298 // Ignore const/volatile/restrict qualifiers.
4299 if (DS.getTypeQualifiers()) {
4300 if (DS.getTypeQualifiers() & DeclSpec::TQ_const)
4301 Diag(DS.getConstSpecLoc(), diag::ext_anonymous_struct_union_qualified)
4302 << Record->isUnion() << "const"
4303 << FixItHint::CreateRemoval(DS.getConstSpecLoc());
4304 if (DS.getTypeQualifiers() & DeclSpec::TQ_volatile)
4305 Diag(DS.getVolatileSpecLoc(),
4306 diag::ext_anonymous_struct_union_qualified)
4307 << Record->isUnion() << "volatile"
4308 << FixItHint::CreateRemoval(DS.getVolatileSpecLoc());
4309 if (DS.getTypeQualifiers() & DeclSpec::TQ_restrict)
4310 Diag(DS.getRestrictSpecLoc(),
4311 diag::ext_anonymous_struct_union_qualified)
4312 << Record->isUnion() << "restrict"
4313 << FixItHint::CreateRemoval(DS.getRestrictSpecLoc());
4314 if (DS.getTypeQualifiers() & DeclSpec::TQ_atomic)
4315 Diag(DS.getAtomicSpecLoc(),
4316 diag::ext_anonymous_struct_union_qualified)
4317 << Record->isUnion() << "_Atomic"
4318 << FixItHint::CreateRemoval(DS.getAtomicSpecLoc());
4319 if (DS.getTypeQualifiers() & DeclSpec::TQ_unaligned)
4320 Diag(DS.getUnalignedSpecLoc(),
4321 diag::ext_anonymous_struct_union_qualified)
4322 << Record->isUnion() << "__unaligned"
4323 << FixItHint::CreateRemoval(DS.getUnalignedSpecLoc());
4325 DS.ClearTypeQualifiers();
4328 // C++ [class.union]p2:
4329 // The member-specification of an anonymous union shall only
4330 // define non-static data members. [Note: nested types and
4331 // functions cannot be declared within an anonymous union. ]
4332 for (auto *Mem : Record->decls()) {
4333 if (auto *FD = dyn_cast<FieldDecl>(Mem)) {
4334 // C++ [class.union]p3:
4335 // An anonymous union shall not have private or protected
4336 // members (clause 11).
4337 assert(FD->getAccess() != AS_none);
4338 if (FD->getAccess() != AS_public) {
4339 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member)
4340 << Record->isUnion() << (FD->getAccess() == AS_protected);
4344 // C++ [class.union]p1
4345 // An object of a class with a non-trivial constructor, a non-trivial
4346 // copy constructor, a non-trivial destructor, or a non-trivial copy
4347 // assignment operator cannot be a member of a union, nor can an
4348 // array of such objects.
4349 if (CheckNontrivialField(FD))
4351 } else if (Mem->isImplicit()) {
4352 // Any implicit members are fine.
4353 } else if (isa<TagDecl>(Mem) && Mem->getDeclContext() != Record) {
4354 // This is a type that showed up in an
4355 // elaborated-type-specifier inside the anonymous struct or
4356 // union, but which actually declares a type outside of the
4357 // anonymous struct or union. It's okay.
4358 } else if (auto *MemRecord = dyn_cast<RecordDecl>(Mem)) {
4359 if (!MemRecord->isAnonymousStructOrUnion() &&
4360 MemRecord->getDeclName()) {
4361 // Visual C++ allows type definition in anonymous struct or union.
4362 if (getLangOpts().MicrosoftExt)
4363 Diag(MemRecord->getLocation(), diag::ext_anonymous_record_with_type)
4364 << Record->isUnion();
4366 // This is a nested type declaration.
4367 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type)
4368 << Record->isUnion();
4372 // This is an anonymous type definition within another anonymous type.
4373 // This is a popular extension, provided by Plan9, MSVC and GCC, but
4374 // not part of standard C++.
4375 Diag(MemRecord->getLocation(),
4376 diag::ext_anonymous_record_with_anonymous_type)
4377 << Record->isUnion();
4379 } else if (isa<AccessSpecDecl>(Mem)) {
4380 // Any access specifier is fine.
4381 } else if (isa<StaticAssertDecl>(Mem)) {
4382 // In C++1z, static_assert declarations are also fine.
4384 // We have something that isn't a non-static data
4385 // member. Complain about it.
4386 unsigned DK = diag::err_anonymous_record_bad_member;
4387 if (isa<TypeDecl>(Mem))
4388 DK = diag::err_anonymous_record_with_type;
4389 else if (isa<FunctionDecl>(Mem))
4390 DK = diag::err_anonymous_record_with_function;
4391 else if (isa<VarDecl>(Mem))
4392 DK = diag::err_anonymous_record_with_static;
4394 // Visual C++ allows type definition in anonymous struct or union.
4395 if (getLangOpts().MicrosoftExt &&
4396 DK == diag::err_anonymous_record_with_type)
4397 Diag(Mem->getLocation(), diag::ext_anonymous_record_with_type)
4398 << Record->isUnion();
4400 Diag(Mem->getLocation(), DK) << Record->isUnion();
4406 // C++11 [class.union]p8 (DR1460):
4407 // At most one variant member of a union may have a
4408 // brace-or-equal-initializer.
4409 if (cast<CXXRecordDecl>(Record)->hasInClassInitializer() &&
4411 checkDuplicateDefaultInit(*this, cast<CXXRecordDecl>(Owner),
4412 cast<CXXRecordDecl>(Record));
4415 if (!Record->isUnion() && !Owner->isRecord()) {
4416 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member)
4417 << getLangOpts().CPlusPlus;
4421 // Mock up a declarator.
4422 Declarator Dc(DS, Declarator::MemberContext);
4423 TypeSourceInfo *TInfo = GetTypeForDeclarator(Dc, S);
4424 assert(TInfo && "couldn't build declarator info for anonymous struct/union");
4426 // Create a declaration for this anonymous struct/union.
4427 NamedDecl *Anon = nullptr;
4428 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) {
4429 Anon = FieldDecl::Create(Context, OwningClass,
4431 Record->getLocation(),
4432 /*IdentifierInfo=*/nullptr,
4433 Context.getTypeDeclType(Record),
4435 /*BitWidth=*/nullptr, /*Mutable=*/false,
4436 /*InitStyle=*/ICIS_NoInit);
4437 Anon->setAccess(AS);
4438 if (getLangOpts().CPlusPlus)
4439 FieldCollector->Add(cast<FieldDecl>(Anon));
4441 DeclSpec::SCS SCSpec = DS.getStorageClassSpec();
4442 StorageClass SC = StorageClassSpecToVarDeclStorageClass(DS);
4443 if (SCSpec == DeclSpec::SCS_mutable) {
4444 // mutable can only appear on non-static class members, so it's always
4446 Diag(Record->getLocation(), diag::err_mutable_nonmember);
4451 Anon = VarDecl::Create(Context, Owner,
4453 Record->getLocation(), /*IdentifierInfo=*/nullptr,
4454 Context.getTypeDeclType(Record),
4457 // Default-initialize the implicit variable. This initialization will be
4458 // trivial in almost all cases, except if a union member has an in-class
4460 // union { int n = 0; };
4461 ActOnUninitializedDecl(Anon, /*TypeMayContainAuto=*/false);
4463 Anon->setImplicit();
4465 // Mark this as an anonymous struct/union type.
4466 Record->setAnonymousStructOrUnion(true);
4468 // Add the anonymous struct/union object to the current
4469 // context. We'll be referencing this object when we refer to one of
4471 Owner->addDecl(Anon);
4473 // Inject the members of the anonymous struct/union into the owning
4474 // context and into the identifier resolver chain for name lookup
4476 SmallVector<NamedDecl*, 2> Chain;
4477 Chain.push_back(Anon);
4479 if (InjectAnonymousStructOrUnionMembers(*this, S, Owner, Record, AS, Chain))
4482 if (VarDecl *NewVD = dyn_cast<VarDecl>(Anon)) {
4483 if (getLangOpts().CPlusPlus && NewVD->isStaticLocal()) {
4484 Decl *ManglingContextDecl;
4485 if (MangleNumberingContext *MCtx = getCurrentMangleNumberContext(
4486 NewVD->getDeclContext(), ManglingContextDecl)) {
4487 Context.setManglingNumber(
4488 NewVD, MCtx->getManglingNumber(
4489 NewVD, getMSManglingNumber(getLangOpts(), S)));
4490 Context.setStaticLocalNumber(NewVD, MCtx->getStaticLocalNumber(NewVD));
4496 Anon->setInvalidDecl();
4501 /// BuildMicrosoftCAnonymousStruct - Handle the declaration of an
4502 /// Microsoft C anonymous structure.
4503 /// Ref: http://msdn.microsoft.com/en-us/library/z2cx9y4f.aspx
4506 /// struct A { int a; };
4507 /// struct B { struct A; int b; };
4514 Decl *Sema::BuildMicrosoftCAnonymousStruct(Scope *S, DeclSpec &DS,
4515 RecordDecl *Record) {
4516 assert(Record && "expected a record!");
4518 // Mock up a declarator.
4519 Declarator Dc(DS, Declarator::TypeNameContext);
4520 TypeSourceInfo *TInfo = GetTypeForDeclarator(Dc, S);
4521 assert(TInfo && "couldn't build declarator info for anonymous struct");
4523 auto *ParentDecl = cast<RecordDecl>(CurContext);
4524 QualType RecTy = Context.getTypeDeclType(Record);
4526 // Create a declaration for this anonymous struct.
4527 NamedDecl *Anon = FieldDecl::Create(Context,
4531 /*IdentifierInfo=*/nullptr,
4534 /*BitWidth=*/nullptr, /*Mutable=*/false,
4535 /*InitStyle=*/ICIS_NoInit);
4536 Anon->setImplicit();
4538 // Add the anonymous struct object to the current context.
4539 CurContext->addDecl(Anon);
4541 // Inject the members of the anonymous struct into the current
4542 // context and into the identifier resolver chain for name lookup
4544 SmallVector<NamedDecl*, 2> Chain;
4545 Chain.push_back(Anon);
4547 RecordDecl *RecordDef = Record->getDefinition();
4548 if (RequireCompleteType(Anon->getLocation(), RecTy,
4549 diag::err_field_incomplete) ||
4550 InjectAnonymousStructOrUnionMembers(*this, S, CurContext, RecordDef,
4552 Anon->setInvalidDecl();
4553 ParentDecl->setInvalidDecl();
4559 /// GetNameForDeclarator - Determine the full declaration name for the
4560 /// given Declarator.
4561 DeclarationNameInfo Sema::GetNameForDeclarator(Declarator &D) {
4562 return GetNameFromUnqualifiedId(D.getName());
4565 /// \brief Retrieves the declaration name from a parsed unqualified-id.
4567 Sema::GetNameFromUnqualifiedId(const UnqualifiedId &Name) {
4568 DeclarationNameInfo NameInfo;
4569 NameInfo.setLoc(Name.StartLocation);
4571 switch (Name.getKind()) {
4573 case UnqualifiedId::IK_ImplicitSelfParam:
4574 case UnqualifiedId::IK_Identifier:
4575 NameInfo.setName(Name.Identifier);
4576 NameInfo.setLoc(Name.StartLocation);
4579 case UnqualifiedId::IK_OperatorFunctionId:
4580 NameInfo.setName(Context.DeclarationNames.getCXXOperatorName(
4581 Name.OperatorFunctionId.Operator));
4582 NameInfo.setLoc(Name.StartLocation);
4583 NameInfo.getInfo().CXXOperatorName.BeginOpNameLoc
4584 = Name.OperatorFunctionId.SymbolLocations[0];
4585 NameInfo.getInfo().CXXOperatorName.EndOpNameLoc
4586 = Name.EndLocation.getRawEncoding();
4589 case UnqualifiedId::IK_LiteralOperatorId:
4590 NameInfo.setName(Context.DeclarationNames.getCXXLiteralOperatorName(
4592 NameInfo.setLoc(Name.StartLocation);
4593 NameInfo.setCXXLiteralOperatorNameLoc(Name.EndLocation);
4596 case UnqualifiedId::IK_ConversionFunctionId: {
4597 TypeSourceInfo *TInfo;
4598 QualType Ty = GetTypeFromParser(Name.ConversionFunctionId, &TInfo);
4600 return DeclarationNameInfo();
4601 NameInfo.setName(Context.DeclarationNames.getCXXConversionFunctionName(
4602 Context.getCanonicalType(Ty)));
4603 NameInfo.setLoc(Name.StartLocation);
4604 NameInfo.setNamedTypeInfo(TInfo);
4608 case UnqualifiedId::IK_ConstructorName: {
4609 TypeSourceInfo *TInfo;
4610 QualType Ty = GetTypeFromParser(Name.ConstructorName, &TInfo);
4612 return DeclarationNameInfo();
4613 NameInfo.setName(Context.DeclarationNames.getCXXConstructorName(
4614 Context.getCanonicalType(Ty)));
4615 NameInfo.setLoc(Name.StartLocation);
4616 NameInfo.setNamedTypeInfo(TInfo);
4620 case UnqualifiedId::IK_ConstructorTemplateId: {
4621 // In well-formed code, we can only have a constructor
4622 // template-id that refers to the current context, so go there
4623 // to find the actual type being constructed.
4624 CXXRecordDecl *CurClass = dyn_cast<CXXRecordDecl>(CurContext);
4625 if (!CurClass || CurClass->getIdentifier() != Name.TemplateId->Name)
4626 return DeclarationNameInfo();
4628 // Determine the type of the class being constructed.
4629 QualType CurClassType = Context.getTypeDeclType(CurClass);
4631 // FIXME: Check two things: that the template-id names the same type as
4632 // CurClassType, and that the template-id does not occur when the name
4635 NameInfo.setName(Context.DeclarationNames.getCXXConstructorName(
4636 Context.getCanonicalType(CurClassType)));
4637 NameInfo.setLoc(Name.StartLocation);
4638 // FIXME: should we retrieve TypeSourceInfo?
4639 NameInfo.setNamedTypeInfo(nullptr);
4643 case UnqualifiedId::IK_DestructorName: {
4644 TypeSourceInfo *TInfo;
4645 QualType Ty = GetTypeFromParser(Name.DestructorName, &TInfo);
4647 return DeclarationNameInfo();
4648 NameInfo.setName(Context.DeclarationNames.getCXXDestructorName(
4649 Context.getCanonicalType(Ty)));
4650 NameInfo.setLoc(Name.StartLocation);
4651 NameInfo.setNamedTypeInfo(TInfo);
4655 case UnqualifiedId::IK_TemplateId: {
4656 TemplateName TName = Name.TemplateId->Template.get();
4657 SourceLocation TNameLoc = Name.TemplateId->TemplateNameLoc;
4658 return Context.getNameForTemplate(TName, TNameLoc);
4661 } // switch (Name.getKind())
4663 llvm_unreachable("Unknown name kind");
4666 static QualType getCoreType(QualType Ty) {
4668 if (Ty->isPointerType() || Ty->isReferenceType())
4669 Ty = Ty->getPointeeType();
4670 else if (Ty->isArrayType())
4671 Ty = Ty->castAsArrayTypeUnsafe()->getElementType();
4673 return Ty.withoutLocalFastQualifiers();
4677 /// hasSimilarParameters - Determine whether the C++ functions Declaration
4678 /// and Definition have "nearly" matching parameters. This heuristic is
4679 /// used to improve diagnostics in the case where an out-of-line function
4680 /// definition doesn't match any declaration within the class or namespace.
4681 /// Also sets Params to the list of indices to the parameters that differ
4682 /// between the declaration and the definition. If hasSimilarParameters
4683 /// returns true and Params is empty, then all of the parameters match.
4684 static bool hasSimilarParameters(ASTContext &Context,
4685 FunctionDecl *Declaration,
4686 FunctionDecl *Definition,
4687 SmallVectorImpl<unsigned> &Params) {
4689 if (Declaration->param_size() != Definition->param_size())
4691 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) {
4692 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType();
4693 QualType DefParamTy = Definition->getParamDecl(Idx)->getType();
4695 // The parameter types are identical
4696 if (Context.hasSameType(DefParamTy, DeclParamTy))
4699 QualType DeclParamBaseTy = getCoreType(DeclParamTy);
4700 QualType DefParamBaseTy = getCoreType(DefParamTy);
4701 const IdentifierInfo *DeclTyName = DeclParamBaseTy.getBaseTypeIdentifier();
4702 const IdentifierInfo *DefTyName = DefParamBaseTy.getBaseTypeIdentifier();
4704 if (Context.hasSameUnqualifiedType(DeclParamBaseTy, DefParamBaseTy) ||
4705 (DeclTyName && DeclTyName == DefTyName))
4706 Params.push_back(Idx);
4707 else // The two parameters aren't even close
4714 /// NeedsRebuildingInCurrentInstantiation - Checks whether the given
4715 /// declarator needs to be rebuilt in the current instantiation.
4716 /// Any bits of declarator which appear before the name are valid for
4717 /// consideration here. That's specifically the type in the decl spec
4718 /// and the base type in any member-pointer chunks.
4719 static bool RebuildDeclaratorInCurrentInstantiation(Sema &S, Declarator &D,
4720 DeclarationName Name) {
4721 // The types we specifically need to rebuild are:
4722 // - typenames, typeofs, and decltypes
4723 // - types which will become injected class names
4724 // Of course, we also need to rebuild any type referencing such a
4725 // type. It's safest to just say "dependent", but we call out a
4728 DeclSpec &DS = D.getMutableDeclSpec();
4729 switch (DS.getTypeSpecType()) {
4730 case DeclSpec::TST_typename:
4731 case DeclSpec::TST_typeofType:
4732 case DeclSpec::TST_underlyingType:
4733 case DeclSpec::TST_atomic: {
4734 // Grab the type from the parser.
4735 TypeSourceInfo *TSI = nullptr;
4736 QualType T = S.GetTypeFromParser(DS.getRepAsType(), &TSI);
4737 if (T.isNull() || !T->isDependentType()) break;
4739 // Make sure there's a type source info. This isn't really much
4740 // of a waste; most dependent types should have type source info
4741 // attached already.
4743 TSI = S.Context.getTrivialTypeSourceInfo(T, DS.getTypeSpecTypeLoc());
4745 // Rebuild the type in the current instantiation.
4746 TSI = S.RebuildTypeInCurrentInstantiation(TSI, D.getIdentifierLoc(), Name);
4747 if (!TSI) return true;
4749 // Store the new type back in the decl spec.
4750 ParsedType LocType = S.CreateParsedType(TSI->getType(), TSI);
4751 DS.UpdateTypeRep(LocType);
4755 case DeclSpec::TST_decltype:
4756 case DeclSpec::TST_typeofExpr: {
4757 Expr *E = DS.getRepAsExpr();
4758 ExprResult Result = S.RebuildExprInCurrentInstantiation(E);
4759 if (Result.isInvalid()) return true;
4760 DS.UpdateExprRep(Result.get());
4765 // Nothing to do for these decl specs.
4769 // It doesn't matter what order we do this in.
4770 for (unsigned I = 0, E = D.getNumTypeObjects(); I != E; ++I) {
4771 DeclaratorChunk &Chunk = D.getTypeObject(I);
4773 // The only type information in the declarator which can come
4774 // before the declaration name is the base type of a member
4776 if (Chunk.Kind != DeclaratorChunk::MemberPointer)
4779 // Rebuild the scope specifier in-place.
4780 CXXScopeSpec &SS = Chunk.Mem.Scope();
4781 if (S.RebuildNestedNameSpecifierInCurrentInstantiation(SS))
4788 Decl *Sema::ActOnDeclarator(Scope *S, Declarator &D) {
4789 D.setFunctionDefinitionKind(FDK_Declaration);
4790 Decl *Dcl = HandleDeclarator(S, D, MultiTemplateParamsArg());
4792 if (OriginalLexicalContext && OriginalLexicalContext->isObjCContainer() &&
4793 Dcl && Dcl->getDeclContext()->isFileContext())
4794 Dcl->setTopLevelDeclInObjCContainer();
4799 /// DiagnoseClassNameShadow - Implement C++ [class.mem]p13:
4800 /// If T is the name of a class, then each of the following shall have a
4801 /// name different from T:
4802 /// - every static data member of class T;
4803 /// - every member function of class T
4804 /// - every member of class T that is itself a type;
4805 /// \returns true if the declaration name violates these rules.
4806 bool Sema::DiagnoseClassNameShadow(DeclContext *DC,
4807 DeclarationNameInfo NameInfo) {
4808 DeclarationName Name = NameInfo.getName();
4810 CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(DC);
4811 while (Record && Record->isAnonymousStructOrUnion())
4812 Record = dyn_cast<CXXRecordDecl>(Record->getParent());
4813 if (Record && Record->getIdentifier() && Record->getDeclName() == Name) {
4814 Diag(NameInfo.getLoc(), diag::err_member_name_of_class) << Name;
4821 /// \brief Diagnose a declaration whose declarator-id has the given
4822 /// nested-name-specifier.
4824 /// \param SS The nested-name-specifier of the declarator-id.
4826 /// \param DC The declaration context to which the nested-name-specifier
4829 /// \param Name The name of the entity being declared.
4831 /// \param Loc The location of the name of the entity being declared.
4833 /// \returns true if we cannot safely recover from this error, false otherwise.
4834 bool Sema::diagnoseQualifiedDeclaration(CXXScopeSpec &SS, DeclContext *DC,
4835 DeclarationName Name,
4836 SourceLocation Loc) {
4837 DeclContext *Cur = CurContext;
4838 while (isa<LinkageSpecDecl>(Cur) || isa<CapturedDecl>(Cur))
4839 Cur = Cur->getParent();
4841 // If the user provided a superfluous scope specifier that refers back to the
4842 // class in which the entity is already declared, diagnose and ignore it.
4848 // Note, it was once ill-formed to give redundant qualification in all
4849 // contexts, but that rule was removed by DR482.
4850 if (Cur->Equals(DC)) {
4851 if (Cur->isRecord()) {
4852 Diag(Loc, LangOpts.MicrosoftExt ? diag::warn_member_extra_qualification
4853 : diag::err_member_extra_qualification)
4854 << Name << FixItHint::CreateRemoval(SS.getRange());
4857 Diag(Loc, diag::warn_namespace_member_extra_qualification) << Name;
4862 // Check whether the qualifying scope encloses the scope of the original
4864 if (!Cur->Encloses(DC)) {
4865 if (Cur->isRecord())
4866 Diag(Loc, diag::err_member_qualification)
4867 << Name << SS.getRange();
4868 else if (isa<TranslationUnitDecl>(DC))
4869 Diag(Loc, diag::err_invalid_declarator_global_scope)
4870 << Name << SS.getRange();
4871 else if (isa<FunctionDecl>(Cur))
4872 Diag(Loc, diag::err_invalid_declarator_in_function)
4873 << Name << SS.getRange();
4874 else if (isa<BlockDecl>(Cur))
4875 Diag(Loc, diag::err_invalid_declarator_in_block)
4876 << Name << SS.getRange();
4878 Diag(Loc, diag::err_invalid_declarator_scope)
4879 << Name << cast<NamedDecl>(Cur) << cast<NamedDecl>(DC) << SS.getRange();
4884 if (Cur->isRecord()) {
4885 // Cannot qualify members within a class.
4886 Diag(Loc, diag::err_member_qualification)
4887 << Name << SS.getRange();
4890 // C++ constructors and destructors with incorrect scopes can break
4891 // our AST invariants by having the wrong underlying types. If
4892 // that's the case, then drop this declaration entirely.
4893 if ((Name.getNameKind() == DeclarationName::CXXConstructorName ||
4894 Name.getNameKind() == DeclarationName::CXXDestructorName) &&
4895 !Context.hasSameType(Name.getCXXNameType(),
4896 Context.getTypeDeclType(cast<CXXRecordDecl>(Cur))))
4902 // C++11 [dcl.meaning]p1:
4903 // [...] "The nested-name-specifier of the qualified declarator-id shall
4904 // not begin with a decltype-specifer"
4905 NestedNameSpecifierLoc SpecLoc(SS.getScopeRep(), SS.location_data());
4906 while (SpecLoc.getPrefix())
4907 SpecLoc = SpecLoc.getPrefix();
4908 if (dyn_cast_or_null<DecltypeType>(
4909 SpecLoc.getNestedNameSpecifier()->getAsType()))
4910 Diag(Loc, diag::err_decltype_in_declarator)
4911 << SpecLoc.getTypeLoc().getSourceRange();
4916 NamedDecl *Sema::HandleDeclarator(Scope *S, Declarator &D,
4917 MultiTemplateParamsArg TemplateParamLists) {
4918 // TODO: consider using NameInfo for diagnostic.
4919 DeclarationNameInfo NameInfo = GetNameForDeclarator(D);
4920 DeclarationName Name = NameInfo.getName();
4922 // All of these full declarators require an identifier. If it doesn't have
4923 // one, the ParsedFreeStandingDeclSpec action should be used.
4925 if (!D.isInvalidType()) // Reject this if we think it is valid.
4926 Diag(D.getDeclSpec().getLocStart(),
4927 diag::err_declarator_need_ident)
4928 << D.getDeclSpec().getSourceRange() << D.getSourceRange();
4930 } else if (DiagnoseUnexpandedParameterPack(NameInfo, UPPC_DeclarationType))
4933 // The scope passed in may not be a decl scope. Zip up the scope tree until
4934 // we find one that is.
4935 while ((S->getFlags() & Scope::DeclScope) == 0 ||
4936 (S->getFlags() & Scope::TemplateParamScope) != 0)
4939 DeclContext *DC = CurContext;
4940 if (D.getCXXScopeSpec().isInvalid())
4942 else if (D.getCXXScopeSpec().isSet()) {
4943 if (DiagnoseUnexpandedParameterPack(D.getCXXScopeSpec(),
4944 UPPC_DeclarationQualifier))
4947 bool EnteringContext = !D.getDeclSpec().isFriendSpecified();
4948 DC = computeDeclContext(D.getCXXScopeSpec(), EnteringContext);
4949 if (!DC || isa<EnumDecl>(DC)) {
4950 // If we could not compute the declaration context, it's because the
4951 // declaration context is dependent but does not refer to a class,
4952 // class template, or class template partial specialization. Complain
4953 // and return early, to avoid the coming semantic disaster.
4954 Diag(D.getIdentifierLoc(),
4955 diag::err_template_qualified_declarator_no_match)
4956 << D.getCXXScopeSpec().getScopeRep()
4957 << D.getCXXScopeSpec().getRange();
4960 bool IsDependentContext = DC->isDependentContext();
4962 if (!IsDependentContext &&
4963 RequireCompleteDeclContext(D.getCXXScopeSpec(), DC))
4966 // If a class is incomplete, do not parse entities inside it.
4967 if (isa<CXXRecordDecl>(DC) && !cast<CXXRecordDecl>(DC)->hasDefinition()) {
4968 Diag(D.getIdentifierLoc(),
4969 diag::err_member_def_undefined_record)
4970 << Name << DC << D.getCXXScopeSpec().getRange();
4973 if (!D.getDeclSpec().isFriendSpecified()) {
4974 if (diagnoseQualifiedDeclaration(D.getCXXScopeSpec(), DC,
4975 Name, D.getIdentifierLoc())) {
4983 // Check whether we need to rebuild the type of the given
4984 // declaration in the current instantiation.
4985 if (EnteringContext && IsDependentContext &&
4986 TemplateParamLists.size() != 0) {
4987 ContextRAII SavedContext(*this, DC);
4988 if (RebuildDeclaratorInCurrentInstantiation(*this, D, Name))
4993 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S);
4994 QualType R = TInfo->getType();
4996 if (!R->isFunctionType() && DiagnoseClassNameShadow(DC, NameInfo))
4997 // If this is a typedef, we'll end up spewing multiple diagnostics.
4998 // Just return early; it's safer. If this is a function, let the
4999 // "constructor cannot have a return type" diagnostic handle it.
5000 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef)
5003 if (DiagnoseUnexpandedParameterPack(D.getIdentifierLoc(), TInfo,
5004 UPPC_DeclarationType))
5007 LookupResult Previous(*this, NameInfo, LookupOrdinaryName,
5010 // See if this is a redefinition of a variable in the same scope.
5011 if (!D.getCXXScopeSpec().isSet()) {
5012 bool IsLinkageLookup = false;
5013 bool CreateBuiltins = false;
5015 // If the declaration we're planning to build will be a function
5016 // or object with linkage, then look for another declaration with
5017 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6).
5019 // If the declaration we're planning to build will be declared with
5020 // external linkage in the translation unit, create any builtin with
5022 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef)
5024 else if (CurContext->isFunctionOrMethod() &&
5025 (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern ||
5026 R->isFunctionType())) {
5027 IsLinkageLookup = true;
5029 CurContext->getEnclosingNamespaceContext()->isTranslationUnit();
5030 } else if (CurContext->getRedeclContext()->isTranslationUnit() &&
5031 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static)
5032 CreateBuiltins = true;
5034 if (IsLinkageLookup)
5035 Previous.clear(LookupRedeclarationWithLinkage);
5037 LookupName(Previous, S, CreateBuiltins);
5038 } else { // Something like "int foo::x;"
5039 LookupQualifiedName(Previous, DC);
5041 // C++ [dcl.meaning]p1:
5042 // When the declarator-id is qualified, the declaration shall refer to a
5043 // previously declared member of the class or namespace to which the
5044 // qualifier refers (or, in the case of a namespace, of an element of the
5045 // inline namespace set of that namespace (7.3.1)) or to a specialization
5048 // Note that we already checked the context above, and that we do not have
5049 // enough information to make sure that Previous contains the declaration
5050 // we want to match. For example, given:
5057 // void X::f(int) { } // ill-formed
5059 // In this case, Previous will point to the overload set
5060 // containing the two f's declared in X, but neither of them
5063 // C++ [dcl.meaning]p1:
5064 // [...] the member shall not merely have been introduced by a
5065 // using-declaration in the scope of the class or namespace nominated by
5066 // the nested-name-specifier of the declarator-id.
5067 RemoveUsingDecls(Previous);
5070 if (Previous.isSingleResult() &&
5071 Previous.getFoundDecl()->isTemplateParameter()) {
5072 // Maybe we will complain about the shadowed template parameter.
5073 if (!D.isInvalidType())
5074 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(),
5075 Previous.getFoundDecl());
5077 // Just pretend that we didn't see the previous declaration.
5081 // In C++, the previous declaration we find might be a tag type
5082 // (class or enum). In this case, the new declaration will hide the
5083 // tag type. Note that this does does not apply if we're declaring a
5084 // typedef (C++ [dcl.typedef]p4).
5085 if (Previous.isSingleTagDecl() &&
5086 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef)
5089 // Check that there are no default arguments other than in the parameters
5090 // of a function declaration (C++ only).
5091 if (getLangOpts().CPlusPlus)
5092 CheckExtraCXXDefaultArguments(D);
5094 if (D.getDeclSpec().isConceptSpecified()) {
5095 // C++ Concepts TS [dcl.spec.concept]p1: The concept specifier shall be
5096 // applied only to the definition of a function template or variable
5097 // template, declared in namespace scope
5098 if (!TemplateParamLists.size()) {
5099 Diag(D.getDeclSpec().getConceptSpecLoc(),
5100 diag:: err_concept_wrong_decl_kind);
5104 if (!DC->getRedeclContext()->isFileContext()) {
5105 Diag(D.getIdentifierLoc(),
5106 diag::err_concept_decls_may_only_appear_in_namespace_scope);
5113 bool AddToScope = true;
5114 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) {
5115 if (TemplateParamLists.size()) {
5116 Diag(D.getIdentifierLoc(), diag::err_template_typedef);
5120 New = ActOnTypedefDeclarator(S, D, DC, TInfo, Previous);
5121 } else if (R->isFunctionType()) {
5122 New = ActOnFunctionDeclarator(S, D, DC, TInfo, Previous,
5126 New = ActOnVariableDeclarator(S, D, DC, TInfo, Previous, TemplateParamLists,
5133 // If this has an identifier and is not a function template specialization,
5134 // add it to the scope stack.
5135 if (New->getDeclName() && AddToScope) {
5136 // Only make a locally-scoped extern declaration visible if it is the first
5137 // declaration of this entity. Qualified lookup for such an entity should
5138 // only find this declaration if there is no visible declaration of it.
5139 bool AddToContext = !D.isRedeclaration() || !New->isLocalExternDecl();
5140 PushOnScopeChains(New, S, AddToContext);
5142 CurContext->addHiddenDecl(New);
5145 if (isInOpenMPDeclareTargetContext())
5146 checkDeclIsAllowedInOpenMPTarget(nullptr, New);
5151 /// Helper method to turn variable array types into constant array
5152 /// types in certain situations which would otherwise be errors (for
5153 /// GCC compatibility).
5154 static QualType TryToFixInvalidVariablyModifiedType(QualType T,
5155 ASTContext &Context,
5156 bool &SizeIsNegative,
5157 llvm::APSInt &Oversized) {
5158 // This method tries to turn a variable array into a constant
5159 // array even when the size isn't an ICE. This is necessary
5160 // for compatibility with code that depends on gcc's buggy
5161 // constant expression folding, like struct {char x[(int)(char*)2];}
5162 SizeIsNegative = false;
5165 if (T->isDependentType())
5168 QualifierCollector Qs;
5169 const Type *Ty = Qs.strip(T);
5171 if (const PointerType* PTy = dyn_cast<PointerType>(Ty)) {
5172 QualType Pointee = PTy->getPointeeType();
5173 QualType FixedType =
5174 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative,
5176 if (FixedType.isNull()) return FixedType;
5177 FixedType = Context.getPointerType(FixedType);
5178 return Qs.apply(Context, FixedType);
5180 if (const ParenType* PTy = dyn_cast<ParenType>(Ty)) {
5181 QualType Inner = PTy->getInnerType();
5182 QualType FixedType =
5183 TryToFixInvalidVariablyModifiedType(Inner, Context, SizeIsNegative,
5185 if (FixedType.isNull()) return FixedType;
5186 FixedType = Context.getParenType(FixedType);
5187 return Qs.apply(Context, FixedType);
5190 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T);
5193 // FIXME: We should probably handle this case
5194 if (VLATy->getElementType()->isVariablyModifiedType())
5198 if (!VLATy->getSizeExpr() ||
5199 !VLATy->getSizeExpr()->EvaluateAsInt(Res, Context))
5202 // Check whether the array size is negative.
5203 if (Res.isSigned() && Res.isNegative()) {
5204 SizeIsNegative = true;
5208 // Check whether the array is too large to be addressed.
5209 unsigned ActiveSizeBits
5210 = ConstantArrayType::getNumAddressingBits(Context, VLATy->getElementType(),
5212 if (ActiveSizeBits > ConstantArrayType::getMaxSizeBits(Context)) {
5217 return Context.getConstantArrayType(VLATy->getElementType(),
5218 Res, ArrayType::Normal, 0);
5222 FixInvalidVariablyModifiedTypeLoc(TypeLoc SrcTL, TypeLoc DstTL) {
5223 SrcTL = SrcTL.getUnqualifiedLoc();
5224 DstTL = DstTL.getUnqualifiedLoc();
5225 if (PointerTypeLoc SrcPTL = SrcTL.getAs<PointerTypeLoc>()) {
5226 PointerTypeLoc DstPTL = DstTL.castAs<PointerTypeLoc>();
5227 FixInvalidVariablyModifiedTypeLoc(SrcPTL.getPointeeLoc(),
5228 DstPTL.getPointeeLoc());
5229 DstPTL.setStarLoc(SrcPTL.getStarLoc());
5232 if (ParenTypeLoc SrcPTL = SrcTL.getAs<ParenTypeLoc>()) {
5233 ParenTypeLoc DstPTL = DstTL.castAs<ParenTypeLoc>();
5234 FixInvalidVariablyModifiedTypeLoc(SrcPTL.getInnerLoc(),
5235 DstPTL.getInnerLoc());
5236 DstPTL.setLParenLoc(SrcPTL.getLParenLoc());
5237 DstPTL.setRParenLoc(SrcPTL.getRParenLoc());
5240 ArrayTypeLoc SrcATL = SrcTL.castAs<ArrayTypeLoc>();
5241 ArrayTypeLoc DstATL = DstTL.castAs<ArrayTypeLoc>();
5242 TypeLoc SrcElemTL = SrcATL.getElementLoc();
5243 TypeLoc DstElemTL = DstATL.getElementLoc();
5244 DstElemTL.initializeFullCopy(SrcElemTL);
5245 DstATL.setLBracketLoc(SrcATL.getLBracketLoc());
5246 DstATL.setSizeExpr(SrcATL.getSizeExpr());
5247 DstATL.setRBracketLoc(SrcATL.getRBracketLoc());
5250 /// Helper method to turn variable array types into constant array
5251 /// types in certain situations which would otherwise be errors (for
5252 /// GCC compatibility).
5253 static TypeSourceInfo*
5254 TryToFixInvalidVariablyModifiedTypeSourceInfo(TypeSourceInfo *TInfo,
5255 ASTContext &Context,
5256 bool &SizeIsNegative,
5257 llvm::APSInt &Oversized) {
5259 = TryToFixInvalidVariablyModifiedType(TInfo->getType(), Context,
5260 SizeIsNegative, Oversized);
5261 if (FixedTy.isNull())
5263 TypeSourceInfo *FixedTInfo = Context.getTrivialTypeSourceInfo(FixedTy);
5264 FixInvalidVariablyModifiedTypeLoc(TInfo->getTypeLoc(),
5265 FixedTInfo->getTypeLoc());
5269 /// \brief Register the given locally-scoped extern "C" declaration so
5270 /// that it can be found later for redeclarations. We include any extern "C"
5271 /// declaration that is not visible in the translation unit here, not just
5272 /// function-scope declarations.
5274 Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, Scope *S) {
5275 if (!getLangOpts().CPlusPlus &&
5276 ND->getLexicalDeclContext()->getRedeclContext()->isTranslationUnit())
5277 // Don't need to track declarations in the TU in C.
5280 // Note that we have a locally-scoped external with this name.
5281 Context.getExternCContextDecl()->makeDeclVisibleInContext(ND);
5284 NamedDecl *Sema::findLocallyScopedExternCDecl(DeclarationName Name) {
5285 // FIXME: We can have multiple results via __attribute__((overloadable)).
5286 auto Result = Context.getExternCContextDecl()->lookup(Name);
5287 return Result.empty() ? nullptr : *Result.begin();
5290 /// \brief Diagnose function specifiers on a declaration of an identifier that
5291 /// does not identify a function.
5292 void Sema::DiagnoseFunctionSpecifiers(const DeclSpec &DS) {
5293 // FIXME: We should probably indicate the identifier in question to avoid
5294 // confusion for constructs like "virtual int a(), b;"
5295 if (DS.isVirtualSpecified())
5296 Diag(DS.getVirtualSpecLoc(),
5297 diag::err_virtual_non_function);
5299 if (DS.isExplicitSpecified())
5300 Diag(DS.getExplicitSpecLoc(),
5301 diag::err_explicit_non_function);
5303 if (DS.isNoreturnSpecified())
5304 Diag(DS.getNoreturnSpecLoc(),
5305 diag::err_noreturn_non_function);
5309 Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC,
5310 TypeSourceInfo *TInfo, LookupResult &Previous) {
5311 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1).
5312 if (D.getCXXScopeSpec().isSet()) {
5313 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator)
5314 << D.getCXXScopeSpec().getRange();
5316 // Pretend we didn't see the scope specifier.
5321 DiagnoseFunctionSpecifiers(D.getDeclSpec());
5323 if (D.getDeclSpec().isInlineSpecified())
5324 Diag(D.getDeclSpec().getInlineSpecLoc(), diag::err_inline_non_function)
5325 << getLangOpts().CPlusPlus1z;
5326 if (D.getDeclSpec().isConstexprSpecified())
5327 Diag(D.getDeclSpec().getConstexprSpecLoc(), diag::err_invalid_constexpr)
5329 if (D.getDeclSpec().isConceptSpecified())
5330 Diag(D.getDeclSpec().getConceptSpecLoc(),
5331 diag::err_concept_wrong_decl_kind);
5333 if (D.getName().Kind != UnqualifiedId::IK_Identifier) {
5334 Diag(D.getName().StartLocation, diag::err_typedef_not_identifier)
5335 << D.getName().getSourceRange();
5339 TypedefDecl *NewTD = ParseTypedefDecl(S, D, TInfo->getType(), TInfo);
5340 if (!NewTD) return nullptr;
5342 // Handle attributes prior to checking for duplicates in MergeVarDecl
5343 ProcessDeclAttributes(S, NewTD, D);
5345 CheckTypedefForVariablyModifiedType(S, NewTD);
5347 bool Redeclaration = D.isRedeclaration();
5348 NamedDecl *ND = ActOnTypedefNameDecl(S, DC, NewTD, Previous, Redeclaration);
5349 D.setRedeclaration(Redeclaration);
5354 Sema::CheckTypedefForVariablyModifiedType(Scope *S, TypedefNameDecl *NewTD) {
5355 // C99 6.7.7p2: If a typedef name specifies a variably modified type
5356 // then it shall have block scope.
5357 // Note that variably modified types must be fixed before merging the decl so
5358 // that redeclarations will match.
5359 TypeSourceInfo *TInfo = NewTD->getTypeSourceInfo();
5360 QualType T = TInfo->getType();
5361 if (T->isVariablyModifiedType()) {
5362 getCurFunction()->setHasBranchProtectedScope();
5364 if (S->getFnParent() == nullptr) {
5365 bool SizeIsNegative;
5366 llvm::APSInt Oversized;
5367 TypeSourceInfo *FixedTInfo =
5368 TryToFixInvalidVariablyModifiedTypeSourceInfo(TInfo, Context,
5372 Diag(NewTD->getLocation(), diag::warn_illegal_constant_array_size);
5373 NewTD->setTypeSourceInfo(FixedTInfo);
5376 Diag(NewTD->getLocation(), diag::err_typecheck_negative_array_size);
5377 else if (T->isVariableArrayType())
5378 Diag(NewTD->getLocation(), diag::err_vla_decl_in_file_scope);
5379 else if (Oversized.getBoolValue())
5380 Diag(NewTD->getLocation(), diag::err_array_too_large)
5381 << Oversized.toString(10);
5383 Diag(NewTD->getLocation(), diag::err_vm_decl_in_file_scope);
5384 NewTD->setInvalidDecl();
5390 /// ActOnTypedefNameDecl - Perform semantic checking for a declaration which
5391 /// declares a typedef-name, either using the 'typedef' type specifier or via
5392 /// a C++0x [dcl.typedef]p2 alias-declaration: 'using T = A;'.
5394 Sema::ActOnTypedefNameDecl(Scope *S, DeclContext *DC, TypedefNameDecl *NewTD,
5395 LookupResult &Previous, bool &Redeclaration) {
5396 // Merge the decl with the existing one if appropriate. If the decl is
5397 // in an outer scope, it isn't the same thing.
5398 FilterLookupForScope(Previous, DC, S, /*ConsiderLinkage*/false,
5399 /*AllowInlineNamespace*/false);
5400 filterNonConflictingPreviousTypedefDecls(*this, NewTD, Previous);
5401 if (!Previous.empty()) {
5402 Redeclaration = true;
5403 MergeTypedefNameDecl(S, NewTD, Previous);
5406 // If this is the C FILE type, notify the AST context.
5407 if (IdentifierInfo *II = NewTD->getIdentifier())
5408 if (!NewTD->isInvalidDecl() &&
5409 NewTD->getDeclContext()->getRedeclContext()->isTranslationUnit()) {
5410 if (II->isStr("FILE"))
5411 Context.setFILEDecl(NewTD);
5412 else if (II->isStr("jmp_buf"))
5413 Context.setjmp_bufDecl(NewTD);
5414 else if (II->isStr("sigjmp_buf"))
5415 Context.setsigjmp_bufDecl(NewTD);
5416 else if (II->isStr("ucontext_t"))
5417 Context.setucontext_tDecl(NewTD);
5423 /// \brief Determines whether the given declaration is an out-of-scope
5424 /// previous declaration.
5426 /// This routine should be invoked when name lookup has found a
5427 /// previous declaration (PrevDecl) that is not in the scope where a
5428 /// new declaration by the same name is being introduced. If the new
5429 /// declaration occurs in a local scope, previous declarations with
5430 /// linkage may still be considered previous declarations (C99
5431 /// 6.2.2p4-5, C++ [basic.link]p6).
5433 /// \param PrevDecl the previous declaration found by name
5436 /// \param DC the context in which the new declaration is being
5439 /// \returns true if PrevDecl is an out-of-scope previous declaration
5440 /// for a new delcaration with the same name.
5442 isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC,
5443 ASTContext &Context) {
5447 if (!PrevDecl->hasLinkage())
5450 if (Context.getLangOpts().CPlusPlus) {
5451 // C++ [basic.link]p6:
5452 // If there is a visible declaration of an entity with linkage
5453 // having the same name and type, ignoring entities declared
5454 // outside the innermost enclosing namespace scope, the block
5455 // scope declaration declares that same entity and receives the
5456 // linkage of the previous declaration.
5457 DeclContext *OuterContext = DC->getRedeclContext();
5458 if (!OuterContext->isFunctionOrMethod())
5459 // This rule only applies to block-scope declarations.
5462 DeclContext *PrevOuterContext = PrevDecl->getDeclContext();
5463 if (PrevOuterContext->isRecord())
5464 // We found a member function: ignore it.
5467 // Find the innermost enclosing namespace for the new and
5468 // previous declarations.
5469 OuterContext = OuterContext->getEnclosingNamespaceContext();
5470 PrevOuterContext = PrevOuterContext->getEnclosingNamespaceContext();
5472 // The previous declaration is in a different namespace, so it
5473 // isn't the same function.
5474 if (!OuterContext->Equals(PrevOuterContext))
5481 static void SetNestedNameSpecifier(DeclaratorDecl *DD, Declarator &D) {
5482 CXXScopeSpec &SS = D.getCXXScopeSpec();
5483 if (!SS.isSet()) return;
5484 DD->setQualifierInfo(SS.getWithLocInContext(DD->getASTContext()));
5487 bool Sema::inferObjCARCLifetime(ValueDecl *decl) {
5488 QualType type = decl->getType();
5489 Qualifiers::ObjCLifetime lifetime = type.getObjCLifetime();
5490 if (lifetime == Qualifiers::OCL_Autoreleasing) {
5491 // Various kinds of declaration aren't allowed to be __autoreleasing.
5492 unsigned kind = -1U;
5493 if (VarDecl *var = dyn_cast<VarDecl>(decl)) {
5494 if (var->hasAttr<BlocksAttr>())
5495 kind = 0; // __block
5496 else if (!var->hasLocalStorage())
5498 } else if (isa<ObjCIvarDecl>(decl)) {
5500 } else if (isa<FieldDecl>(decl)) {
5505 Diag(decl->getLocation(), diag::err_arc_autoreleasing_var)
5508 } else if (lifetime == Qualifiers::OCL_None) {
5509 // Try to infer lifetime.
5510 if (!type->isObjCLifetimeType())
5513 lifetime = type->getObjCARCImplicitLifetime();
5514 type = Context.getLifetimeQualifiedType(type, lifetime);
5515 decl->setType(type);
5518 if (VarDecl *var = dyn_cast<VarDecl>(decl)) {
5519 // Thread-local variables cannot have lifetime.
5520 if (lifetime && lifetime != Qualifiers::OCL_ExplicitNone &&
5521 var->getTLSKind()) {
5522 Diag(var->getLocation(), diag::err_arc_thread_ownership)
5531 static void checkAttributesAfterMerging(Sema &S, NamedDecl &ND) {
5532 // Ensure that an auto decl is deduced otherwise the checks below might cache
5533 // the wrong linkage.
5534 assert(S.ParsingInitForAutoVars.count(&ND) == 0);
5536 // 'weak' only applies to declarations with external linkage.
5537 if (WeakAttr *Attr = ND.getAttr<WeakAttr>()) {
5538 if (!ND.isExternallyVisible()) {
5539 S.Diag(Attr->getLocation(), diag::err_attribute_weak_static);
5540 ND.dropAttr<WeakAttr>();
5543 if (WeakRefAttr *Attr = ND.getAttr<WeakRefAttr>()) {
5544 if (ND.isExternallyVisible()) {
5545 S.Diag(Attr->getLocation(), diag::err_attribute_weakref_not_static);
5546 ND.dropAttr<WeakRefAttr>();
5547 ND.dropAttr<AliasAttr>();
5551 if (auto *VD = dyn_cast<VarDecl>(&ND)) {
5552 if (VD->hasInit()) {
5553 if (const auto *Attr = VD->getAttr<AliasAttr>()) {
5554 assert(VD->isThisDeclarationADefinition() &&
5555 !VD->isExternallyVisible() && "Broken AliasAttr handled late!");
5556 S.Diag(Attr->getLocation(), diag::err_alias_is_definition) << VD << 0;
5557 VD->dropAttr<AliasAttr>();
5562 // 'selectany' only applies to externally visible variable declarations.
5563 // It does not apply to functions.
5564 if (SelectAnyAttr *Attr = ND.getAttr<SelectAnyAttr>()) {
5565 if (isa<FunctionDecl>(ND) || !ND.isExternallyVisible()) {
5566 S.Diag(Attr->getLocation(),
5567 diag::err_attribute_selectany_non_extern_data);
5568 ND.dropAttr<SelectAnyAttr>();
5572 if (const InheritableAttr *Attr = getDLLAttr(&ND)) {
5573 // dll attributes require external linkage. Static locals may have external
5574 // linkage but still cannot be explicitly imported or exported.
5575 auto *VD = dyn_cast<VarDecl>(&ND);
5576 if (!ND.isExternallyVisible() || (VD && VD->isStaticLocal())) {
5577 S.Diag(ND.getLocation(), diag::err_attribute_dll_not_extern)
5579 ND.setInvalidDecl();
5583 // Virtual functions cannot be marked as 'notail'.
5584 if (auto *Attr = ND.getAttr<NotTailCalledAttr>())
5585 if (auto *MD = dyn_cast<CXXMethodDecl>(&ND))
5586 if (MD->isVirtual()) {
5587 S.Diag(ND.getLocation(),
5588 diag::err_invalid_attribute_on_virtual_function)
5590 ND.dropAttr<NotTailCalledAttr>();
5594 static void checkDLLAttributeRedeclaration(Sema &S, NamedDecl *OldDecl,
5596 bool IsSpecialization,
5597 bool IsDefinition) {
5598 if (TemplateDecl *OldTD = dyn_cast<TemplateDecl>(OldDecl)) {
5599 OldDecl = OldTD->getTemplatedDecl();
5600 if (!IsSpecialization)
5601 IsDefinition = false;
5603 if (TemplateDecl *NewTD = dyn_cast<TemplateDecl>(NewDecl))
5604 NewDecl = NewTD->getTemplatedDecl();
5606 if (!OldDecl || !NewDecl)
5609 const DLLImportAttr *OldImportAttr = OldDecl->getAttr<DLLImportAttr>();
5610 const DLLExportAttr *OldExportAttr = OldDecl->getAttr<DLLExportAttr>();
5611 const DLLImportAttr *NewImportAttr = NewDecl->getAttr<DLLImportAttr>();
5612 const DLLExportAttr *NewExportAttr = NewDecl->getAttr<DLLExportAttr>();
5614 // dllimport and dllexport are inheritable attributes so we have to exclude
5615 // inherited attribute instances.
5616 bool HasNewAttr = (NewImportAttr && !NewImportAttr->isInherited()) ||
5617 (NewExportAttr && !NewExportAttr->isInherited());
5619 // A redeclaration is not allowed to add a dllimport or dllexport attribute,
5620 // the only exception being explicit specializations.
5621 // Implicitly generated declarations are also excluded for now because there
5622 // is no other way to switch these to use dllimport or dllexport.
5623 bool AddsAttr = !(OldImportAttr || OldExportAttr) && HasNewAttr;
5625 if (AddsAttr && !IsSpecialization && !OldDecl->isImplicit()) {
5626 // Allow with a warning for free functions and global variables.
5627 bool JustWarn = false;
5628 if (!OldDecl->isCXXClassMember()) {
5629 auto *VD = dyn_cast<VarDecl>(OldDecl);
5630 if (VD && !VD->getDescribedVarTemplate())
5632 auto *FD = dyn_cast<FunctionDecl>(OldDecl);
5633 if (FD && FD->getTemplatedKind() == FunctionDecl::TK_NonTemplate)
5637 // We cannot change a declaration that's been used because IR has already
5638 // been emitted. Dllimported functions will still work though (modulo
5639 // address equality) as they can use the thunk.
5640 if (OldDecl->isUsed())
5641 if (!isa<FunctionDecl>(OldDecl) || !NewImportAttr)
5644 unsigned DiagID = JustWarn ? diag::warn_attribute_dll_redeclaration
5645 : diag::err_attribute_dll_redeclaration;
5646 S.Diag(NewDecl->getLocation(), DiagID)
5648 << (NewImportAttr ? (const Attr *)NewImportAttr : NewExportAttr);
5649 S.Diag(OldDecl->getLocation(), diag::note_previous_declaration);
5651 NewDecl->setInvalidDecl();
5656 // A redeclaration is not allowed to drop a dllimport attribute, the only
5657 // exceptions being inline function definitions, local extern declarations,
5658 // qualified friend declarations or special MSVC extension: in the last case,
5659 // the declaration is treated as if it were marked dllexport.
5660 bool IsInline = false, IsStaticDataMember = false, IsQualifiedFriend = false;
5661 bool IsMicrosoft = S.Context.getTargetInfo().getCXXABI().isMicrosoft();
5662 if (const auto *VD = dyn_cast<VarDecl>(NewDecl)) {
5663 // Ignore static data because out-of-line definitions are diagnosed
5665 IsStaticDataMember = VD->isStaticDataMember();
5666 IsDefinition = VD->isThisDeclarationADefinition(S.Context) !=
5667 VarDecl::DeclarationOnly;
5668 } else if (const auto *FD = dyn_cast<FunctionDecl>(NewDecl)) {
5669 IsInline = FD->isInlined();
5670 IsQualifiedFriend = FD->getQualifier() &&
5671 FD->getFriendObjectKind() == Decl::FOK_Declared;
5674 if (OldImportAttr && !HasNewAttr && !IsInline && !IsStaticDataMember &&
5675 !NewDecl->isLocalExternDecl() && !IsQualifiedFriend) {
5676 if (IsMicrosoft && IsDefinition) {
5677 S.Diag(NewDecl->getLocation(),
5678 diag::warn_redeclaration_without_import_attribute)
5680 S.Diag(OldDecl->getLocation(), diag::note_previous_declaration);
5681 NewDecl->dropAttr<DLLImportAttr>();
5682 NewDecl->addAttr(::new (S.Context) DLLExportAttr(
5683 NewImportAttr->getRange(), S.Context,
5684 NewImportAttr->getSpellingListIndex()));
5686 S.Diag(NewDecl->getLocation(),
5687 diag::warn_redeclaration_without_attribute_prev_attribute_ignored)
5688 << NewDecl << OldImportAttr;
5689 S.Diag(OldDecl->getLocation(), diag::note_previous_declaration);
5690 S.Diag(OldImportAttr->getLocation(), diag::note_previous_attribute);
5691 OldDecl->dropAttr<DLLImportAttr>();
5692 NewDecl->dropAttr<DLLImportAttr>();
5694 } else if (IsInline && OldImportAttr && !IsMicrosoft) {
5695 // In MinGW, seeing a function declared inline drops the dllimport attribute.
5696 OldDecl->dropAttr<DLLImportAttr>();
5697 NewDecl->dropAttr<DLLImportAttr>();
5698 S.Diag(NewDecl->getLocation(),
5699 diag::warn_dllimport_dropped_from_inline_function)
5700 << NewDecl << OldImportAttr;
5704 /// Given that we are within the definition of the given function,
5705 /// will that definition behave like C99's 'inline', where the
5706 /// definition is discarded except for optimization purposes?
5707 static bool isFunctionDefinitionDiscarded(Sema &S, FunctionDecl *FD) {
5708 // Try to avoid calling GetGVALinkageForFunction.
5710 // All cases of this require the 'inline' keyword.
5711 if (!FD->isInlined()) return false;
5713 // This is only possible in C++ with the gnu_inline attribute.
5714 if (S.getLangOpts().CPlusPlus && !FD->hasAttr<GNUInlineAttr>())
5717 // Okay, go ahead and call the relatively-more-expensive function.
5720 // AST quite reasonably asserts that it's working on a function
5721 // definition. We don't really have a way to tell it that we're
5722 // currently defining the function, so just lie to it in +Asserts
5723 // builds. This is an awful hack.
5728 S.Context.GetGVALinkageForFunction(FD) == GVA_AvailableExternally;
5737 /// Determine whether a variable is extern "C" prior to attaching
5738 /// an initializer. We can't just call isExternC() here, because that
5739 /// will also compute and cache whether the declaration is externally
5740 /// visible, which might change when we attach the initializer.
5742 /// This can only be used if the declaration is known to not be a
5743 /// redeclaration of an internal linkage declaration.
5749 /// Attaching the initializer here makes this declaration not externally
5750 /// visible, because its type has internal linkage.
5752 /// FIXME: This is a hack.
5753 template<typename T>
5754 static bool isIncompleteDeclExternC(Sema &S, const T *D) {
5755 if (S.getLangOpts().CPlusPlus) {
5756 // In C++, the overloadable attribute negates the effects of extern "C".
5757 if (!D->isInExternCContext() || D->template hasAttr<OverloadableAttr>())
5760 // So do CUDA's host/device attributes.
5761 if (S.getLangOpts().CUDA && (D->template hasAttr<CUDADeviceAttr>() ||
5762 D->template hasAttr<CUDAHostAttr>()))
5765 return D->isExternC();
5768 static bool shouldConsiderLinkage(const VarDecl *VD) {
5769 const DeclContext *DC = VD->getDeclContext()->getRedeclContext();
5770 if (DC->isFunctionOrMethod() || isa<OMPDeclareReductionDecl>(DC))
5771 return VD->hasExternalStorage();
5772 if (DC->isFileContext())
5776 llvm_unreachable("Unexpected context");
5779 static bool shouldConsiderLinkage(const FunctionDecl *FD) {
5780 const DeclContext *DC = FD->getDeclContext()->getRedeclContext();
5781 if (DC->isFileContext() || DC->isFunctionOrMethod() ||
5782 isa<OMPDeclareReductionDecl>(DC))
5786 llvm_unreachable("Unexpected context");
5789 static bool hasParsedAttr(Scope *S, const AttributeList *AttrList,
5790 AttributeList::Kind Kind) {
5791 for (const AttributeList *L = AttrList; L; L = L->getNext())
5792 if (L->getKind() == Kind)
5797 static bool hasParsedAttr(Scope *S, const Declarator &PD,
5798 AttributeList::Kind Kind) {
5799 // Check decl attributes on the DeclSpec.
5800 if (hasParsedAttr(S, PD.getDeclSpec().getAttributes().getList(), Kind))
5803 // Walk the declarator structure, checking decl attributes that were in a type
5804 // position to the decl itself.
5805 for (unsigned I = 0, E = PD.getNumTypeObjects(); I != E; ++I) {
5806 if (hasParsedAttr(S, PD.getTypeObject(I).getAttrs(), Kind))
5810 // Finally, check attributes on the decl itself.
5811 return hasParsedAttr(S, PD.getAttributes(), Kind);
5814 /// Adjust the \c DeclContext for a function or variable that might be a
5815 /// function-local external declaration.
5816 bool Sema::adjustContextForLocalExternDecl(DeclContext *&DC) {
5817 if (!DC->isFunctionOrMethod())
5820 // If this is a local extern function or variable declared within a function
5821 // template, don't add it into the enclosing namespace scope until it is
5822 // instantiated; it might have a dependent type right now.
5823 if (DC->isDependentContext())
5826 // C++11 [basic.link]p7:
5827 // When a block scope declaration of an entity with linkage is not found to
5828 // refer to some other declaration, then that entity is a member of the
5829 // innermost enclosing namespace.
5831 // Per C++11 [namespace.def]p6, the innermost enclosing namespace is a
5832 // semantically-enclosing namespace, not a lexically-enclosing one.
5833 while (!DC->isFileContext() && !isa<LinkageSpecDecl>(DC))
5834 DC = DC->getParent();
5838 /// \brief Returns true if given declaration has external C language linkage.
5839 static bool isDeclExternC(const Decl *D) {
5840 if (const auto *FD = dyn_cast<FunctionDecl>(D))
5841 return FD->isExternC();
5842 if (const auto *VD = dyn_cast<VarDecl>(D))
5843 return VD->isExternC();
5845 llvm_unreachable("Unknown type of decl!");
5849 Sema::ActOnVariableDeclarator(Scope *S, Declarator &D, DeclContext *DC,
5850 TypeSourceInfo *TInfo, LookupResult &Previous,
5851 MultiTemplateParamsArg TemplateParamLists,
5853 QualType R = TInfo->getType();
5854 DeclarationName Name = GetNameForDeclarator(D).getName();
5856 // OpenCL v2.0 s6.9.b - Image type can only be used as a function argument.
5857 // OpenCL v2.0 s6.13.16.1 - Pipe type can only be used as a function
5859 if (getLangOpts().OpenCL && (R->isImageType() || R->isPipeType())) {
5860 Diag(D.getIdentifierLoc(),
5861 diag::err_opencl_type_can_only_be_used_as_function_parameter)
5867 DeclSpec::SCS SCSpec = D.getDeclSpec().getStorageClassSpec();
5868 StorageClass SC = StorageClassSpecToVarDeclStorageClass(D.getDeclSpec());
5870 // dllimport globals without explicit storage class are treated as extern. We
5871 // have to change the storage class this early to get the right DeclContext.
5872 if (SC == SC_None && !DC->isRecord() &&
5873 hasParsedAttr(S, D, AttributeList::AT_DLLImport) &&
5874 !hasParsedAttr(S, D, AttributeList::AT_DLLExport))
5877 DeclContext *OriginalDC = DC;
5878 bool IsLocalExternDecl = SC == SC_Extern &&
5879 adjustContextForLocalExternDecl(DC);
5881 if (getLangOpts().OpenCL) {
5882 // OpenCL v1.0 s6.8.a.3: Pointers to functions are not allowed.
5884 while (NR->isPointerType()) {
5885 if (NR->isFunctionPointerType()) {
5886 Diag(D.getIdentifierLoc(), diag::err_opencl_function_pointer_variable);
5890 NR = NR->getPointeeType();
5893 if (!getOpenCLOptions().cl_khr_fp16) {
5894 // OpenCL v1.2 s6.1.1.1: reject declaring variables of the half and
5895 // half array type (unless the cl_khr_fp16 extension is enabled).
5896 if (Context.getBaseElementType(R)->isHalfType()) {
5897 Diag(D.getIdentifierLoc(), diag::err_opencl_half_declaration) << R;
5903 if (SCSpec == DeclSpec::SCS_mutable) {
5904 // mutable can only appear on non-static class members, so it's always
5906 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember);
5911 if (getLangOpts().CPlusPlus11 && SCSpec == DeclSpec::SCS_register &&
5912 !D.getAsmLabel() && !getSourceManager().isInSystemMacro(
5913 D.getDeclSpec().getStorageClassSpecLoc())) {
5914 // In C++11, the 'register' storage class specifier is deprecated.
5915 // Suppress the warning in system macros, it's used in macros in some
5916 // popular C system headers, such as in glibc's htonl() macro.
5917 Diag(D.getDeclSpec().getStorageClassSpecLoc(),
5918 getLangOpts().CPlusPlus1z ? diag::ext_register_storage_class
5919 : diag::warn_deprecated_register)
5920 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc());
5923 IdentifierInfo *II = Name.getAsIdentifierInfo();
5925 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name)
5930 DiagnoseFunctionSpecifiers(D.getDeclSpec());
5932 if (!DC->isRecord() && S->getFnParent() == nullptr) {
5933 // C99 6.9p2: The storage-class specifiers auto and register shall not
5934 // appear in the declaration specifiers in an external declaration.
5935 // Global Register+Asm is a GNU extension we support.
5936 if (SC == SC_Auto || (SC == SC_Register && !D.getAsmLabel())) {
5937 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope);
5942 if (getLangOpts().OpenCL) {
5943 // OpenCL v1.2 s6.9.b p4:
5944 // The sampler type cannot be used with the __local and __global address
5945 // space qualifiers.
5946 if (R->isSamplerT() && (R.getAddressSpace() == LangAS::opencl_local ||
5947 R.getAddressSpace() == LangAS::opencl_global)) {
5948 Diag(D.getIdentifierLoc(), diag::err_wrong_sampler_addressspace);
5951 // OpenCL 1.2 spec, p6.9 r:
5952 // The event type cannot be used to declare a program scope variable.
5953 // The event type cannot be used with the __local, __constant and __global
5954 // address space qualifiers.
5955 if (R->isEventT()) {
5956 if (S->getParent() == nullptr) {
5957 Diag(D.getLocStart(), diag::err_event_t_global_var);
5961 if (R.getAddressSpace()) {
5962 Diag(D.getLocStart(), diag::err_event_t_addr_space_qual);
5968 bool IsExplicitSpecialization = false;
5969 bool IsVariableTemplateSpecialization = false;
5970 bool IsPartialSpecialization = false;
5971 bool IsVariableTemplate = false;
5972 VarDecl *NewVD = nullptr;
5973 VarTemplateDecl *NewTemplate = nullptr;
5974 TemplateParameterList *TemplateParams = nullptr;
5975 if (!getLangOpts().CPlusPlus) {
5976 NewVD = VarDecl::Create(Context, DC, D.getLocStart(),
5977 D.getIdentifierLoc(), II,
5980 if (D.getDeclSpec().containsPlaceholderType() && R->getContainedAutoType())
5981 ParsingInitForAutoVars.insert(NewVD);
5983 if (D.isInvalidType())
5984 NewVD->setInvalidDecl();
5986 bool Invalid = false;
5988 if (DC->isRecord() && !CurContext->isRecord()) {
5989 // This is an out-of-line definition of a static data member.
5994 Diag(D.getDeclSpec().getStorageClassSpecLoc(),
5995 diag::err_static_out_of_line)
5996 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc());
6001 // [dcl.stc] p2: The auto or register specifiers shall be applied only
6002 // to names of variables declared in a block or to function parameters.
6003 // [dcl.stc] p6: The extern specifier cannot be used in the declaration
6006 Diag(D.getDeclSpec().getStorageClassSpecLoc(),
6007 diag::err_storage_class_for_static_member)
6008 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc());
6010 case SC_PrivateExtern:
6011 llvm_unreachable("C storage class in c++!");
6015 if (SC == SC_Static && CurContext->isRecord()) {
6016 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) {
6017 if (RD->isLocalClass())
6018 Diag(D.getIdentifierLoc(),
6019 diag::err_static_data_member_not_allowed_in_local_class)
6020 << Name << RD->getDeclName();
6022 // C++98 [class.union]p1: If a union contains a static data member,
6023 // the program is ill-formed. C++11 drops this restriction.
6025 Diag(D.getIdentifierLoc(),
6026 getLangOpts().CPlusPlus11
6027 ? diag::warn_cxx98_compat_static_data_member_in_union
6028 : diag::ext_static_data_member_in_union) << Name;
6029 // We conservatively disallow static data members in anonymous structs.
6030 else if (!RD->getDeclName())
6031 Diag(D.getIdentifierLoc(),
6032 diag::err_static_data_member_not_allowed_in_anon_struct)
6033 << Name << RD->isUnion();
6037 // Match up the template parameter lists with the scope specifier, then
6038 // determine whether we have a template or a template specialization.
6039 TemplateParams = MatchTemplateParametersToScopeSpecifier(
6040 D.getDeclSpec().getLocStart(), D.getIdentifierLoc(),
6041 D.getCXXScopeSpec(),
6042 D.getName().getKind() == UnqualifiedId::IK_TemplateId
6043 ? D.getName().TemplateId
6046 /*never a friend*/ false, IsExplicitSpecialization, Invalid);
6048 if (TemplateParams) {
6049 if (!TemplateParams->size() &&
6050 D.getName().getKind() != UnqualifiedId::IK_TemplateId) {
6051 // There is an extraneous 'template<>' for this variable. Complain
6052 // about it, but allow the declaration of the variable.
6053 Diag(TemplateParams->getTemplateLoc(),
6054 diag::err_template_variable_noparams)
6056 << SourceRange(TemplateParams->getTemplateLoc(),
6057 TemplateParams->getRAngleLoc());
6058 TemplateParams = nullptr;
6060 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) {
6061 // This is an explicit specialization or a partial specialization.
6062 // FIXME: Check that we can declare a specialization here.
6063 IsVariableTemplateSpecialization = true;
6064 IsPartialSpecialization = TemplateParams->size() > 0;
6065 } else { // if (TemplateParams->size() > 0)
6066 // This is a template declaration.
6067 IsVariableTemplate = true;
6069 // Check that we can declare a template here.
6070 if (CheckTemplateDeclScope(S, TemplateParams))
6073 // Only C++1y supports variable templates (N3651).
6074 Diag(D.getIdentifierLoc(),
6075 getLangOpts().CPlusPlus14
6076 ? diag::warn_cxx11_compat_variable_template
6077 : diag::ext_variable_template);
6082 (Invalid || D.getName().getKind() != UnqualifiedId::IK_TemplateId) &&
6083 "should have a 'template<>' for this decl");
6086 if (IsVariableTemplateSpecialization) {
6087 SourceLocation TemplateKWLoc =
6088 TemplateParamLists.size() > 0
6089 ? TemplateParamLists[0]->getTemplateLoc()
6091 DeclResult Res = ActOnVarTemplateSpecialization(
6092 S, D, TInfo, TemplateKWLoc, TemplateParams, SC,
6093 IsPartialSpecialization);
6094 if (Res.isInvalid())
6096 NewVD = cast<VarDecl>(Res.get());
6099 NewVD = VarDecl::Create(Context, DC, D.getLocStart(),
6100 D.getIdentifierLoc(), II, R, TInfo, SC);
6102 // If this is supposed to be a variable template, create it as such.
6103 if (IsVariableTemplate) {
6105 VarTemplateDecl::Create(Context, DC, D.getIdentifierLoc(), Name,
6106 TemplateParams, NewVD);
6107 NewVD->setDescribedVarTemplate(NewTemplate);
6110 // If this decl has an auto type in need of deduction, make a note of the
6111 // Decl so we can diagnose uses of it in its own initializer.
6112 if (D.getDeclSpec().containsPlaceholderType() && R->getContainedAutoType())
6113 ParsingInitForAutoVars.insert(NewVD);
6115 if (D.isInvalidType() || Invalid) {
6116 NewVD->setInvalidDecl();
6118 NewTemplate->setInvalidDecl();
6121 SetNestedNameSpecifier(NewVD, D);
6123 // If we have any template parameter lists that don't directly belong to
6124 // the variable (matching the scope specifier), store them.
6125 unsigned VDTemplateParamLists = TemplateParams ? 1 : 0;
6126 if (TemplateParamLists.size() > VDTemplateParamLists)
6127 NewVD->setTemplateParameterListsInfo(
6128 Context, TemplateParamLists.drop_back(VDTemplateParamLists));
6130 if (D.getDeclSpec().isConstexprSpecified()) {
6131 NewVD->setConstexpr(true);
6132 // C++1z [dcl.spec.constexpr]p1:
6133 // A static data member declared with the constexpr specifier is
6134 // implicitly an inline variable.
6135 if (NewVD->isStaticDataMember() && getLangOpts().CPlusPlus1z)
6136 NewVD->setImplicitlyInline();
6139 if (D.getDeclSpec().isConceptSpecified()) {
6140 if (VarTemplateDecl *VTD = NewVD->getDescribedVarTemplate())
6143 // C++ Concepts TS [dcl.spec.concept]p2: A concept definition shall not
6144 // be declared with the thread_local, inline, friend, or constexpr
6145 // specifiers, [...]
6146 if (D.getDeclSpec().getThreadStorageClassSpec() == TSCS_thread_local) {
6147 Diag(D.getDeclSpec().getThreadStorageClassSpecLoc(),
6148 diag::err_concept_decl_invalid_specifiers)
6150 NewVD->setInvalidDecl(true);
6153 if (D.getDeclSpec().isConstexprSpecified()) {
6154 Diag(D.getDeclSpec().getConstexprSpecLoc(),
6155 diag::err_concept_decl_invalid_specifiers)
6157 NewVD->setInvalidDecl(true);
6160 // C++ Concepts TS [dcl.spec.concept]p1: The concept specifier shall be
6161 // applied only to the definition of a function template or variable
6162 // template, declared in namespace scope.
6163 if (IsVariableTemplateSpecialization) {
6164 Diag(D.getDeclSpec().getConceptSpecLoc(),
6165 diag::err_concept_specified_specialization)
6166 << (IsPartialSpecialization ? 2 : 1);
6169 // C++ Concepts TS [dcl.spec.concept]p6: A variable concept has the
6170 // following restrictions:
6171 // - The declared type shall have the type bool.
6172 if (!Context.hasSameType(NewVD->getType(), Context.BoolTy) &&
6173 !NewVD->isInvalidDecl()) {
6174 Diag(D.getIdentifierLoc(), diag::err_variable_concept_bool_decl);
6175 NewVD->setInvalidDecl(true);
6180 if (D.getDeclSpec().isInlineSpecified()) {
6181 if (CurContext->isFunctionOrMethod()) {
6182 // 'inline' is not allowed on block scope variable declaration.
6183 Diag(D.getDeclSpec().getInlineSpecLoc(),
6184 diag::err_inline_declaration_block_scope) << Name
6185 << FixItHint::CreateRemoval(D.getDeclSpec().getInlineSpecLoc());
6187 Diag(D.getDeclSpec().getInlineSpecLoc(),
6188 getLangOpts().CPlusPlus1z ? diag::warn_cxx14_compat_inline_variable
6189 : diag::ext_inline_variable);
6190 NewVD->setInlineSpecified();
6194 // Set the lexical context. If the declarator has a C++ scope specifier, the
6195 // lexical context will be different from the semantic context.
6196 NewVD->setLexicalDeclContext(CurContext);
6198 NewTemplate->setLexicalDeclContext(CurContext);
6200 if (IsLocalExternDecl)
6201 NewVD->setLocalExternDecl();
6203 bool EmitTLSUnsupportedError = false;
6204 if (DeclSpec::TSCS TSCS = D.getDeclSpec().getThreadStorageClassSpec()) {
6205 // C++11 [dcl.stc]p4:
6206 // When thread_local is applied to a variable of block scope the
6207 // storage-class-specifier static is implied if it does not appear
6209 // Core issue: 'static' is not implied if the variable is declared
6211 if (NewVD->hasLocalStorage() &&
6212 (SCSpec != DeclSpec::SCS_unspecified ||
6213 TSCS != DeclSpec::TSCS_thread_local ||
6214 !DC->isFunctionOrMethod()))
6215 Diag(D.getDeclSpec().getThreadStorageClassSpecLoc(),
6216 diag::err_thread_non_global)
6217 << DeclSpec::getSpecifierName(TSCS);
6218 else if (!Context.getTargetInfo().isTLSSupported()) {
6219 if (getLangOpts().CUDA) {
6220 // Postpone error emission until we've collected attributes required to
6221 // figure out whether it's a host or device variable and whether the
6222 // error should be ignored.
6223 EmitTLSUnsupportedError = true;
6224 // We still need to mark the variable as TLS so it shows up in AST with
6225 // proper storage class for other tools to use even if we're not going
6226 // to emit any code for it.
6227 NewVD->setTSCSpec(TSCS);
6229 Diag(D.getDeclSpec().getThreadStorageClassSpecLoc(),
6230 diag::err_thread_unsupported);
6232 NewVD->setTSCSpec(TSCS);
6236 // An inline definition of a function with external linkage shall
6237 // not contain a definition of a modifiable object with static or
6238 // thread storage duration...
6239 // We only apply this when the function is required to be defined
6240 // elsewhere, i.e. when the function is not 'extern inline'. Note
6241 // that a local variable with thread storage duration still has to
6242 // be marked 'static'. Also note that it's possible to get these
6243 // semantics in C++ using __attribute__((gnu_inline)).
6244 if (SC == SC_Static && S->getFnParent() != nullptr &&
6245 !NewVD->getType().isConstQualified()) {
6246 FunctionDecl *CurFD = getCurFunctionDecl();
6247 if (CurFD && isFunctionDefinitionDiscarded(*this, CurFD)) {
6248 Diag(D.getDeclSpec().getStorageClassSpecLoc(),
6249 diag::warn_static_local_in_extern_inline);
6250 MaybeSuggestAddingStaticToDecl(CurFD);
6254 if (D.getDeclSpec().isModulePrivateSpecified()) {
6255 if (IsVariableTemplateSpecialization)
6256 Diag(NewVD->getLocation(), diag::err_module_private_specialization)
6257 << (IsPartialSpecialization ? 1 : 0)
6258 << FixItHint::CreateRemoval(
6259 D.getDeclSpec().getModulePrivateSpecLoc());
6260 else if (IsExplicitSpecialization)
6261 Diag(NewVD->getLocation(), diag::err_module_private_specialization)
6263 << FixItHint::CreateRemoval(D.getDeclSpec().getModulePrivateSpecLoc());
6264 else if (NewVD->hasLocalStorage())
6265 Diag(NewVD->getLocation(), diag::err_module_private_local)
6266 << 0 << NewVD->getDeclName()
6267 << SourceRange(D.getDeclSpec().getModulePrivateSpecLoc())
6268 << FixItHint::CreateRemoval(D.getDeclSpec().getModulePrivateSpecLoc());
6270 NewVD->setModulePrivate();
6272 NewTemplate->setModulePrivate();
6276 // Handle attributes prior to checking for duplicates in MergeVarDecl
6277 ProcessDeclAttributes(S, NewVD, D);
6279 if (getLangOpts().CUDA) {
6280 if (EmitTLSUnsupportedError && DeclAttrsMatchCUDAMode(getLangOpts(), NewVD))
6281 Diag(D.getDeclSpec().getThreadStorageClassSpecLoc(),
6282 diag::err_thread_unsupported);
6283 // CUDA B.2.5: "__shared__ and __constant__ variables have implied static
6284 // storage [duration]."
6285 if (SC == SC_None && S->getFnParent() != nullptr &&
6286 (NewVD->hasAttr<CUDASharedAttr>() ||
6287 NewVD->hasAttr<CUDAConstantAttr>())) {
6288 NewVD->setStorageClass(SC_Static);
6292 // Ensure that dllimport globals without explicit storage class are treated as
6293 // extern. The storage class is set above using parsed attributes. Now we can
6294 // check the VarDecl itself.
6295 assert(!NewVD->hasAttr<DLLImportAttr>() ||
6296 NewVD->getAttr<DLLImportAttr>()->isInherited() ||
6297 NewVD->isStaticDataMember() || NewVD->getStorageClass() != SC_None);
6299 // In auto-retain/release, infer strong retension for variables of
6301 if (getLangOpts().ObjCAutoRefCount && inferObjCARCLifetime(NewVD))
6302 NewVD->setInvalidDecl();
6304 // Handle GNU asm-label extension (encoded as an attribute).
6305 if (Expr *E = (Expr*)D.getAsmLabel()) {
6306 // The parser guarantees this is a string.
6307 StringLiteral *SE = cast<StringLiteral>(E);
6308 StringRef Label = SE->getString();
6309 if (S->getFnParent() != nullptr) {
6313 Diag(E->getExprLoc(), diag::warn_asm_label_on_auto_decl) << Label;
6316 // Local Named register
6317 if (!Context.getTargetInfo().isValidGCCRegisterName(Label) &&
6318 DeclAttrsMatchCUDAMode(getLangOpts(), getCurFunctionDecl()))
6319 Diag(E->getExprLoc(), diag::err_asm_unknown_register_name) << Label;
6323 case SC_PrivateExtern:
6326 } else if (SC == SC_Register) {
6327 // Global Named register
6328 if (DeclAttrsMatchCUDAMode(getLangOpts(), NewVD)) {
6329 const auto &TI = Context.getTargetInfo();
6330 bool HasSizeMismatch;
6332 if (!TI.isValidGCCRegisterName(Label))
6333 Diag(E->getExprLoc(), diag::err_asm_unknown_register_name) << Label;
6334 else if (!TI.validateGlobalRegisterVariable(Label,
6335 Context.getTypeSize(R),
6337 Diag(E->getExprLoc(), diag::err_asm_invalid_global_var_reg) << Label;
6338 else if (HasSizeMismatch)
6339 Diag(E->getExprLoc(), diag::err_asm_register_size_mismatch) << Label;
6342 if (!R->isIntegralType(Context) && !R->isPointerType()) {
6343 Diag(D.getLocStart(), diag::err_asm_bad_register_type);
6344 NewVD->setInvalidDecl(true);
6348 NewVD->addAttr(::new (Context) AsmLabelAttr(SE->getStrTokenLoc(0),
6349 Context, Label, 0));
6350 } else if (!ExtnameUndeclaredIdentifiers.empty()) {
6351 llvm::DenseMap<IdentifierInfo*,AsmLabelAttr*>::iterator I =
6352 ExtnameUndeclaredIdentifiers.find(NewVD->getIdentifier());
6353 if (I != ExtnameUndeclaredIdentifiers.end()) {
6354 if (isDeclExternC(NewVD)) {
6355 NewVD->addAttr(I->second);
6356 ExtnameUndeclaredIdentifiers.erase(I);
6358 Diag(NewVD->getLocation(), diag::warn_redefine_extname_not_applied)
6359 << /*Variable*/1 << NewVD;
6363 // Diagnose shadowed variables before filtering for scope.
6364 if (D.getCXXScopeSpec().isEmpty())
6365 CheckShadow(S, NewVD, Previous);
6367 // Don't consider existing declarations that are in a different
6368 // scope and are out-of-semantic-context declarations (if the new
6369 // declaration has linkage).
6370 FilterLookupForScope(Previous, OriginalDC, S, shouldConsiderLinkage(NewVD),
6371 D.getCXXScopeSpec().isNotEmpty() ||
6372 IsExplicitSpecialization ||
6373 IsVariableTemplateSpecialization);
6375 // Check whether the previous declaration is in the same block scope. This
6376 // affects whether we merge types with it, per C++11 [dcl.array]p3.
6377 if (getLangOpts().CPlusPlus &&
6378 NewVD->isLocalVarDecl() && NewVD->hasExternalStorage())
6379 NewVD->setPreviousDeclInSameBlockScope(
6380 Previous.isSingleResult() && !Previous.isShadowed() &&
6381 isDeclInScope(Previous.getFoundDecl(), OriginalDC, S, false));
6383 if (!getLangOpts().CPlusPlus) {
6384 D.setRedeclaration(CheckVariableDeclaration(NewVD, Previous));
6386 // If this is an explicit specialization of a static data member, check it.
6387 if (IsExplicitSpecialization && !NewVD->isInvalidDecl() &&
6388 CheckMemberSpecialization(NewVD, Previous))
6389 NewVD->setInvalidDecl();
6391 // Merge the decl with the existing one if appropriate.
6392 if (!Previous.empty()) {
6393 if (Previous.isSingleResult() &&
6394 isa<FieldDecl>(Previous.getFoundDecl()) &&
6395 D.getCXXScopeSpec().isSet()) {
6396 // The user tried to define a non-static data member
6397 // out-of-line (C++ [dcl.meaning]p1).
6398 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line)
6399 << D.getCXXScopeSpec().getRange();
6401 NewVD->setInvalidDecl();
6403 } else if (D.getCXXScopeSpec().isSet()) {
6404 // No previous declaration in the qualifying scope.
6405 Diag(D.getIdentifierLoc(), diag::err_no_member)
6406 << Name << computeDeclContext(D.getCXXScopeSpec(), true)
6407 << D.getCXXScopeSpec().getRange();
6408 NewVD->setInvalidDecl();
6411 if (!IsVariableTemplateSpecialization)
6412 D.setRedeclaration(CheckVariableDeclaration(NewVD, Previous));
6414 // C++ Concepts TS [dcl.spec.concept]p7: A program shall not declare [...]
6415 // an explicit specialization (14.8.3) or a partial specialization of a
6416 // concept definition.
6417 if (IsVariableTemplateSpecialization &&
6418 !D.getDeclSpec().isConceptSpecified() && !Previous.empty() &&
6419 Previous.isSingleResult()) {
6420 NamedDecl *PreviousDecl = Previous.getFoundDecl();
6421 if (VarTemplateDecl *VarTmpl = dyn_cast<VarTemplateDecl>(PreviousDecl)) {
6422 if (VarTmpl->isConcept()) {
6423 Diag(NewVD->getLocation(), diag::err_concept_specialized)
6425 << (IsPartialSpecialization ? 2 /*partially specialized*/
6426 : 1 /*explicitly specialized*/);
6427 Diag(VarTmpl->getLocation(), diag::note_previous_declaration);
6428 NewVD->setInvalidDecl();
6434 VarTemplateDecl *PrevVarTemplate =
6435 NewVD->getPreviousDecl()
6436 ? NewVD->getPreviousDecl()->getDescribedVarTemplate()
6439 // Check the template parameter list of this declaration, possibly
6440 // merging in the template parameter list from the previous variable
6441 // template declaration.
6442 if (CheckTemplateParameterList(
6444 PrevVarTemplate ? PrevVarTemplate->getTemplateParameters()
6446 (D.getCXXScopeSpec().isSet() && DC && DC->isRecord() &&
6447 DC->isDependentContext())
6448 ? TPC_ClassTemplateMember
6450 NewVD->setInvalidDecl();
6452 // If we are providing an explicit specialization of a static variable
6453 // template, make a note of that.
6454 if (PrevVarTemplate &&
6455 PrevVarTemplate->getInstantiatedFromMemberTemplate())
6456 PrevVarTemplate->setMemberSpecialization();
6460 ProcessPragmaWeak(S, NewVD);
6462 // If this is the first declaration of an extern C variable, update
6463 // the map of such variables.
6464 if (NewVD->isFirstDecl() && !NewVD->isInvalidDecl() &&
6465 isIncompleteDeclExternC(*this, NewVD))
6466 RegisterLocallyScopedExternCDecl(NewVD, S);
6468 if (getLangOpts().CPlusPlus && NewVD->isStaticLocal()) {
6469 Decl *ManglingContextDecl;
6470 if (MangleNumberingContext *MCtx = getCurrentMangleNumberContext(
6471 NewVD->getDeclContext(), ManglingContextDecl)) {
6472 Context.setManglingNumber(
6473 NewVD, MCtx->getManglingNumber(
6474 NewVD, getMSManglingNumber(getLangOpts(), S)));
6475 Context.setStaticLocalNumber(NewVD, MCtx->getStaticLocalNumber(NewVD));
6479 // Special handling of variable named 'main'.
6480 if (Name.isIdentifier() && Name.getAsIdentifierInfo()->isStr("main") &&
6481 NewVD->getDeclContext()->getRedeclContext()->isTranslationUnit() &&
6482 !getLangOpts().Freestanding && !NewVD->getDescribedVarTemplate()) {
6484 // C++ [basic.start.main]p3
6485 // A program that declares a variable main at global scope is ill-formed.
6486 if (getLangOpts().CPlusPlus)
6487 Diag(D.getLocStart(), diag::err_main_global_variable);
6489 // In C, and external-linkage variable named main results in undefined
6491 else if (NewVD->hasExternalFormalLinkage())
6492 Diag(D.getLocStart(), diag::warn_main_redefined);
6495 if (D.isRedeclaration() && !Previous.empty()) {
6496 checkDLLAttributeRedeclaration(
6497 *this, dyn_cast<NamedDecl>(Previous.getRepresentativeDecl()), NewVD,
6498 IsExplicitSpecialization, D.isFunctionDefinition());
6502 if (NewVD->isInvalidDecl())
6503 NewTemplate->setInvalidDecl();
6504 ActOnDocumentableDecl(NewTemplate);
6511 /// Enum describing the %select options in diag::warn_decl_shadow.
6512 enum ShadowedDeclKind { SDK_Local, SDK_Global, SDK_StaticMember, SDK_Field };
6514 /// Determine what kind of declaration we're shadowing.
6515 static ShadowedDeclKind computeShadowedDeclKind(const NamedDecl *ShadowedDecl,
6516 const DeclContext *OldDC) {
6517 if (isa<RecordDecl>(OldDC))
6518 return isa<FieldDecl>(ShadowedDecl) ? SDK_Field : SDK_StaticMember;
6519 return OldDC->isFileContext() ? SDK_Global : SDK_Local;
6522 /// \brief Diagnose variable or built-in function shadowing. Implements
6525 /// This method is called whenever a VarDecl is added to a "useful"
6528 /// \param S the scope in which the shadowing name is being declared
6529 /// \param R the lookup of the name
6531 void Sema::CheckShadow(Scope *S, VarDecl *D, const LookupResult& R) {
6532 // Return if warning is ignored.
6533 if (Diags.isIgnored(diag::warn_decl_shadow, R.getNameLoc()))
6536 // Don't diagnose declarations at file scope.
6537 if (D->hasGlobalStorage())
6540 DeclContext *NewDC = D->getDeclContext();
6542 // Only diagnose if we're shadowing an unambiguous field or variable.
6543 if (R.getResultKind() != LookupResult::Found)
6546 NamedDecl* ShadowedDecl = R.getFoundDecl();
6547 if (!isa<VarDecl>(ShadowedDecl) && !isa<FieldDecl>(ShadowedDecl))
6550 if (FieldDecl *FD = dyn_cast<FieldDecl>(ShadowedDecl)) {
6551 // Fields are not shadowed by variables in C++ static methods.
6552 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(NewDC))
6556 // Fields shadowed by constructor parameters are a special case. Usually
6557 // the constructor initializes the field with the parameter.
6558 if (isa<CXXConstructorDecl>(NewDC) && isa<ParmVarDecl>(D)) {
6559 // Remember that this was shadowed so we can either warn about its
6560 // modification or its existence depending on warning settings.
6561 D = D->getCanonicalDecl();
6562 ShadowingDecls.insert({D, FD});
6567 if (VarDecl *shadowedVar = dyn_cast<VarDecl>(ShadowedDecl))
6568 if (shadowedVar->isExternC()) {
6569 // For shadowing external vars, make sure that we point to the global
6570 // declaration, not a locally scoped extern declaration.
6571 for (auto I : shadowedVar->redecls())
6572 if (I->isFileVarDecl()) {
6578 DeclContext *OldDC = ShadowedDecl->getDeclContext();
6580 // Only warn about certain kinds of shadowing for class members.
6581 if (NewDC && NewDC->isRecord()) {
6582 // In particular, don't warn about shadowing non-class members.
6583 if (!OldDC->isRecord())
6586 // TODO: should we warn about static data members shadowing
6587 // static data members from base classes?
6589 // TODO: don't diagnose for inaccessible shadowed members.
6590 // This is hard to do perfectly because we might friend the
6591 // shadowing context, but that's just a false negative.
6595 DeclarationName Name = R.getLookupName();
6597 // Emit warning and note.
6598 if (getSourceManager().isInSystemMacro(R.getNameLoc()))
6600 ShadowedDeclKind Kind = computeShadowedDeclKind(ShadowedDecl, OldDC);
6601 Diag(R.getNameLoc(), diag::warn_decl_shadow) << Name << Kind << OldDC;
6602 Diag(ShadowedDecl->getLocation(), diag::note_previous_declaration);
6605 /// \brief Check -Wshadow without the advantage of a previous lookup.
6606 void Sema::CheckShadow(Scope *S, VarDecl *D) {
6607 if (Diags.isIgnored(diag::warn_decl_shadow, D->getLocation()))
6610 LookupResult R(*this, D->getDeclName(), D->getLocation(),
6611 Sema::LookupOrdinaryName, Sema::ForRedeclaration);
6613 CheckShadow(S, D, R);
6616 /// Check if 'E', which is an expression that is about to be modified, refers
6617 /// to a constructor parameter that shadows a field.
6618 void Sema::CheckShadowingDeclModification(Expr *E, SourceLocation Loc) {
6619 // Quickly ignore expressions that can't be shadowing ctor parameters.
6620 if (!getLangOpts().CPlusPlus || ShadowingDecls.empty())
6622 E = E->IgnoreParenImpCasts();
6623 auto *DRE = dyn_cast<DeclRefExpr>(E);
6626 const NamedDecl *D = cast<NamedDecl>(DRE->getDecl()->getCanonicalDecl());
6627 auto I = ShadowingDecls.find(D);
6628 if (I == ShadowingDecls.end())
6630 const NamedDecl *ShadowedDecl = I->second;
6631 const DeclContext *OldDC = ShadowedDecl->getDeclContext();
6632 Diag(Loc, diag::warn_modifying_shadowing_decl) << D << OldDC;
6633 Diag(D->getLocation(), diag::note_var_declared_here) << D;
6634 Diag(ShadowedDecl->getLocation(), diag::note_previous_declaration);
6636 // Avoid issuing multiple warnings about the same decl.
6637 ShadowingDecls.erase(I);
6640 /// Check for conflict between this global or extern "C" declaration and
6641 /// previous global or extern "C" declarations. This is only used in C++.
6642 template<typename T>
6643 static bool checkGlobalOrExternCConflict(
6644 Sema &S, const T *ND, bool IsGlobal, LookupResult &Previous) {
6645 assert(S.getLangOpts().CPlusPlus && "only C++ has extern \"C\"");
6646 NamedDecl *Prev = S.findLocallyScopedExternCDecl(ND->getDeclName());
6648 if (!Prev && IsGlobal && !isIncompleteDeclExternC(S, ND)) {
6649 // The common case: this global doesn't conflict with any extern "C"
6655 if (!IsGlobal || isIncompleteDeclExternC(S, ND)) {
6656 // Both the old and new declarations have C language linkage. This is a
6659 Previous.addDecl(Prev);
6663 // This is a global, non-extern "C" declaration, and there is a previous
6664 // non-global extern "C" declaration. Diagnose if this is a variable
6666 if (!isa<VarDecl>(ND))
6669 // The declaration is extern "C". Check for any declaration in the
6670 // translation unit which might conflict.
6672 // We have already performed the lookup into the translation unit.
6674 for (LookupResult::iterator I = Previous.begin(), E = Previous.end();
6676 if (isa<VarDecl>(*I)) {
6682 DeclContext::lookup_result R =
6683 S.Context.getTranslationUnitDecl()->lookup(ND->getDeclName());
6684 for (DeclContext::lookup_result::iterator I = R.begin(), E = R.end();
6686 if (isa<VarDecl>(*I)) {
6690 // FIXME: If we have any other entity with this name in global scope,
6691 // the declaration is ill-formed, but that is a defect: it breaks the
6692 // 'stat' hack, for instance. Only variables can have mangled name
6693 // clashes with extern "C" declarations, so only they deserve a
6702 // Use the first declaration's location to ensure we point at something which
6703 // is lexically inside an extern "C" linkage-spec.
6704 assert(Prev && "should have found a previous declaration to diagnose");
6705 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(Prev))
6706 Prev = FD->getFirstDecl();
6708 Prev = cast<VarDecl>(Prev)->getFirstDecl();
6710 S.Diag(ND->getLocation(), diag::err_extern_c_global_conflict)
6712 S.Diag(Prev->getLocation(), diag::note_extern_c_global_conflict)
6717 /// Apply special rules for handling extern "C" declarations. Returns \c true
6718 /// if we have found that this is a redeclaration of some prior entity.
6720 /// Per C++ [dcl.link]p6:
6721 /// Two declarations [for a function or variable] with C language linkage
6722 /// with the same name that appear in different scopes refer to the same
6723 /// [entity]. An entity with C language linkage shall not be declared with
6724 /// the same name as an entity in global scope.
6725 template<typename T>
6726 static bool checkForConflictWithNonVisibleExternC(Sema &S, const T *ND,
6727 LookupResult &Previous) {
6728 if (!S.getLangOpts().CPlusPlus) {
6729 // In C, when declaring a global variable, look for a corresponding 'extern'
6730 // variable declared in function scope. We don't need this in C++, because
6731 // we find local extern decls in the surrounding file-scope DeclContext.
6732 if (ND->getDeclContext()->getRedeclContext()->isTranslationUnit()) {
6733 if (NamedDecl *Prev = S.findLocallyScopedExternCDecl(ND->getDeclName())) {
6735 Previous.addDecl(Prev);
6742 // A declaration in the translation unit can conflict with an extern "C"
6744 if (ND->getDeclContext()->getRedeclContext()->isTranslationUnit())
6745 return checkGlobalOrExternCConflict(S, ND, /*IsGlobal*/true, Previous);
6747 // An extern "C" declaration can conflict with a declaration in the
6748 // translation unit or can be a redeclaration of an extern "C" declaration
6749 // in another scope.
6750 if (isIncompleteDeclExternC(S,ND))
6751 return checkGlobalOrExternCConflict(S, ND, /*IsGlobal*/false, Previous);
6753 // Neither global nor extern "C": nothing to do.
6757 void Sema::CheckVariableDeclarationType(VarDecl *NewVD) {
6758 // If the decl is already known invalid, don't check it.
6759 if (NewVD->isInvalidDecl())
6762 TypeSourceInfo *TInfo = NewVD->getTypeSourceInfo();
6763 QualType T = TInfo->getType();
6765 // Defer checking an 'auto' type until its initializer is attached.
6766 if (T->isUndeducedType())
6769 if (NewVD->hasAttrs())
6770 CheckAlignasUnderalignment(NewVD);
6772 if (T->isObjCObjectType()) {
6773 Diag(NewVD->getLocation(), diag::err_statically_allocated_object)
6774 << FixItHint::CreateInsertion(NewVD->getLocation(), "*");
6775 T = Context.getObjCObjectPointerType(T);
6779 // Emit an error if an address space was applied to decl with local storage.
6780 // This includes arrays of objects with address space qualifiers, but not
6781 // automatic variables that point to other address spaces.
6782 // ISO/IEC TR 18037 S5.1.2
6783 if (!getLangOpts().OpenCL
6784 && NewVD->hasLocalStorage() && T.getAddressSpace() != 0) {
6785 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl);
6786 NewVD->setInvalidDecl();
6790 // OpenCL v1.2 s6.8 - The static qualifier is valid only in program
6792 if (getLangOpts().OpenCLVersion == 120 &&
6793 !getOpenCLOptions().cl_clang_storage_class_specifiers &&
6794 NewVD->isStaticLocal()) {
6795 Diag(NewVD->getLocation(), diag::err_static_function_scope);
6796 NewVD->setInvalidDecl();
6800 if (getLangOpts().OpenCL) {
6801 // OpenCL v2.0 s6.12.5 - The __block storage type is not supported.
6802 if (NewVD->hasAttr<BlocksAttr>()) {
6803 Diag(NewVD->getLocation(), diag::err_opencl_block_storage_type);
6807 if (T->isBlockPointerType()) {
6808 // OpenCL v2.0 s6.12.5 - Any block declaration must be const qualified and
6809 // can't use 'extern' storage class.
6810 if (!T.isConstQualified()) {
6811 Diag(NewVD->getLocation(), diag::err_opencl_invalid_block_declaration)
6813 NewVD->setInvalidDecl();
6816 if (NewVD->hasExternalStorage()) {
6817 Diag(NewVD->getLocation(), diag::err_opencl_extern_block_declaration);
6818 NewVD->setInvalidDecl();
6821 // OpenCL v2.0 s6.12.5 - Blocks with variadic arguments are not supported.
6822 // TODO: this check is not enough as it doesn't diagnose the typedef
6823 const BlockPointerType *BlkTy = T->getAs<BlockPointerType>();
6824 const FunctionProtoType *FTy =
6825 BlkTy->getPointeeType()->getAs<FunctionProtoType>();
6826 if (FTy && FTy->isVariadic()) {
6827 Diag(NewVD->getLocation(), diag::err_opencl_block_proto_variadic)
6828 << T << NewVD->getSourceRange();
6829 NewVD->setInvalidDecl();
6833 // OpenCL v1.2 s6.5 - All program scope variables must be declared in the
6834 // __constant address space.
6835 // OpenCL v2.0 s6.5.1 - Variables defined at program scope and static
6836 // variables inside a function can also be declared in the global
6838 if (NewVD->isFileVarDecl() || NewVD->isStaticLocal() ||
6839 NewVD->hasExternalStorage()) {
6840 if (!T->isSamplerT() &&
6841 !(T.getAddressSpace() == LangAS::opencl_constant ||
6842 (T.getAddressSpace() == LangAS::opencl_global &&
6843 getLangOpts().OpenCLVersion == 200))) {
6844 int Scope = NewVD->isStaticLocal() | NewVD->hasExternalStorage() << 1;
6845 if (getLangOpts().OpenCLVersion == 200)
6846 Diag(NewVD->getLocation(), diag::err_opencl_global_invalid_addr_space)
6847 << Scope << "global or constant";
6849 Diag(NewVD->getLocation(), diag::err_opencl_global_invalid_addr_space)
6850 << Scope << "constant";
6851 NewVD->setInvalidDecl();
6855 if (T.getAddressSpace() == LangAS::opencl_global) {
6856 Diag(NewVD->getLocation(), diag::err_opencl_function_variable)
6857 << 1 /*is any function*/ << "global";
6858 NewVD->setInvalidDecl();
6861 // OpenCL v1.1 s6.5.2 and s6.5.3 no local or constant variables
6863 if (T.getAddressSpace() == LangAS::opencl_constant ||
6864 T.getAddressSpace() == LangAS::opencl_local) {
6865 FunctionDecl *FD = getCurFunctionDecl();
6866 if (FD && !FD->hasAttr<OpenCLKernelAttr>()) {
6867 if (T.getAddressSpace() == LangAS::opencl_constant)
6868 Diag(NewVD->getLocation(), diag::err_opencl_function_variable)
6869 << 0 /*non-kernel only*/ << "constant";
6871 Diag(NewVD->getLocation(), diag::err_opencl_function_variable)
6872 << 0 /*non-kernel only*/ << "local";
6873 NewVD->setInvalidDecl();
6880 if (NewVD->hasLocalStorage() && T.isObjCGCWeak()
6881 && !NewVD->hasAttr<BlocksAttr>()) {
6882 if (getLangOpts().getGC() != LangOptions::NonGC)
6883 Diag(NewVD->getLocation(), diag::warn_gc_attribute_weak_on_local);
6885 assert(!getLangOpts().ObjCAutoRefCount);
6886 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local);
6890 bool isVM = T->isVariablyModifiedType();
6891 if (isVM || NewVD->hasAttr<CleanupAttr>() ||
6892 NewVD->hasAttr<BlocksAttr>())
6893 getCurFunction()->setHasBranchProtectedScope();
6895 if ((isVM && NewVD->hasLinkage()) ||
6896 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) {
6897 bool SizeIsNegative;
6898 llvm::APSInt Oversized;
6899 TypeSourceInfo *FixedTInfo =
6900 TryToFixInvalidVariablyModifiedTypeSourceInfo(TInfo, Context,
6901 SizeIsNegative, Oversized);
6902 if (!FixedTInfo && T->isVariableArrayType()) {
6903 const VariableArrayType *VAT = Context.getAsVariableArrayType(T);
6904 // FIXME: This won't give the correct result for
6906 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange();
6908 if (NewVD->isFileVarDecl())
6909 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope)
6911 else if (NewVD->isStaticLocal())
6912 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage)
6915 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage)
6917 NewVD->setInvalidDecl();
6922 if (NewVD->isFileVarDecl())
6923 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope);
6925 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage);
6926 NewVD->setInvalidDecl();
6930 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size);
6931 NewVD->setType(FixedTInfo->getType());
6932 NewVD->setTypeSourceInfo(FixedTInfo);
6935 if (T->isVoidType()) {
6936 // C++98 [dcl.stc]p5: The extern specifier can be applied only to the names
6937 // of objects and functions.
6938 if (NewVD->isThisDeclarationADefinition() || getLangOpts().CPlusPlus) {
6939 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type)
6941 NewVD->setInvalidDecl();
6946 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) {
6947 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal);
6948 NewVD->setInvalidDecl();
6952 if (isVM && NewVD->hasAttr<BlocksAttr>()) {
6953 Diag(NewVD->getLocation(), diag::err_block_on_vm);
6954 NewVD->setInvalidDecl();
6958 if (NewVD->isConstexpr() && !T->isDependentType() &&
6959 RequireLiteralType(NewVD->getLocation(), T,
6960 diag::err_constexpr_var_non_literal)) {
6961 NewVD->setInvalidDecl();
6966 /// \brief Perform semantic checking on a newly-created variable
6969 /// This routine performs all of the type-checking required for a
6970 /// variable declaration once it has been built. It is used both to
6971 /// check variables after they have been parsed and their declarators
6972 /// have been translated into a declaration, and to check variables
6973 /// that have been instantiated from a template.
6975 /// Sets NewVD->isInvalidDecl() if an error was encountered.
6977 /// Returns true if the variable declaration is a redeclaration.
6978 bool Sema::CheckVariableDeclaration(VarDecl *NewVD, LookupResult &Previous) {
6979 CheckVariableDeclarationType(NewVD);
6981 // If the decl is already known invalid, don't check it.
6982 if (NewVD->isInvalidDecl())
6985 // If we did not find anything by this name, look for a non-visible
6986 // extern "C" declaration with the same name.
6987 if (Previous.empty() &&
6988 checkForConflictWithNonVisibleExternC(*this, NewVD, Previous))
6989 Previous.setShadowed();
6991 if (!Previous.empty()) {
6992 MergeVarDecl(NewVD, Previous);
6999 struct FindOverriddenMethod {
7001 CXXMethodDecl *Method;
7003 /// Member lookup function that determines whether a given C++
7004 /// method overrides a method in a base class, to be used with
7005 /// CXXRecordDecl::lookupInBases().
7006 bool operator()(const CXXBaseSpecifier *Specifier, CXXBasePath &Path) {
7007 RecordDecl *BaseRecord =
7008 Specifier->getType()->getAs<RecordType>()->getDecl();
7010 DeclarationName Name = Method->getDeclName();
7012 // FIXME: Do we care about other names here too?
7013 if (Name.getNameKind() == DeclarationName::CXXDestructorName) {
7014 // We really want to find the base class destructor here.
7015 QualType T = S->Context.getTypeDeclType(BaseRecord);
7016 CanQualType CT = S->Context.getCanonicalType(T);
7018 Name = S->Context.DeclarationNames.getCXXDestructorName(CT);
7021 for (Path.Decls = BaseRecord->lookup(Name); !Path.Decls.empty();
7022 Path.Decls = Path.Decls.slice(1)) {
7023 NamedDecl *D = Path.Decls.front();
7024 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(D)) {
7025 if (MD->isVirtual() && !S->IsOverload(Method, MD, false))
7034 enum OverrideErrorKind { OEK_All, OEK_NonDeleted, OEK_Deleted };
7035 } // end anonymous namespace
7037 /// \brief Report an error regarding overriding, along with any relevant
7038 /// overriden methods.
7040 /// \param DiagID the primary error to report.
7041 /// \param MD the overriding method.
7042 /// \param OEK which overrides to include as notes.
7043 static void ReportOverrides(Sema& S, unsigned DiagID, const CXXMethodDecl *MD,
7044 OverrideErrorKind OEK = OEK_All) {
7045 S.Diag(MD->getLocation(), DiagID) << MD->getDeclName();
7046 for (CXXMethodDecl::method_iterator I = MD->begin_overridden_methods(),
7047 E = MD->end_overridden_methods();
7049 // This check (& the OEK parameter) could be replaced by a predicate, but
7050 // without lambdas that would be overkill. This is still nicer than writing
7051 // out the diag loop 3 times.
7052 if ((OEK == OEK_All) ||
7053 (OEK == OEK_NonDeleted && !(*I)->isDeleted()) ||
7054 (OEK == OEK_Deleted && (*I)->isDeleted()))
7055 S.Diag((*I)->getLocation(), diag::note_overridden_virtual_function);
7059 /// AddOverriddenMethods - See if a method overrides any in the base classes,
7060 /// and if so, check that it's a valid override and remember it.
7061 bool Sema::AddOverriddenMethods(CXXRecordDecl *DC, CXXMethodDecl *MD) {
7062 // Look for methods in base classes that this method might override.
7064 FindOverriddenMethod FOM;
7067 bool hasDeletedOverridenMethods = false;
7068 bool hasNonDeletedOverridenMethods = false;
7069 bool AddedAny = false;
7070 if (DC->lookupInBases(FOM, Paths)) {
7071 for (auto *I : Paths.found_decls()) {
7072 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(I)) {
7073 MD->addOverriddenMethod(OldMD->getCanonicalDecl());
7074 if (!CheckOverridingFunctionReturnType(MD, OldMD) &&
7075 !CheckOverridingFunctionAttributes(MD, OldMD) &&
7076 !CheckOverridingFunctionExceptionSpec(MD, OldMD) &&
7077 !CheckIfOverriddenFunctionIsMarkedFinal(MD, OldMD)) {
7078 hasDeletedOverridenMethods |= OldMD->isDeleted();
7079 hasNonDeletedOverridenMethods |= !OldMD->isDeleted();
7086 if (hasDeletedOverridenMethods && !MD->isDeleted()) {
7087 ReportOverrides(*this, diag::err_non_deleted_override, MD, OEK_Deleted);
7089 if (hasNonDeletedOverridenMethods && MD->isDeleted()) {
7090 ReportOverrides(*this, diag::err_deleted_override, MD, OEK_NonDeleted);
7097 // Struct for holding all of the extra arguments needed by
7098 // DiagnoseInvalidRedeclaration to call Sema::ActOnFunctionDeclarator.
7099 struct ActOnFDArgs {
7102 MultiTemplateParamsArg TemplateParamLists;
7105 } // end anonymous namespace
7109 // Callback to only accept typo corrections that have a non-zero edit distance.
7110 // Also only accept corrections that have the same parent decl.
7111 class DifferentNameValidatorCCC : public CorrectionCandidateCallback {
7113 DifferentNameValidatorCCC(ASTContext &Context, FunctionDecl *TypoFD,
7114 CXXRecordDecl *Parent)
7115 : Context(Context), OriginalFD(TypoFD),
7116 ExpectedParent(Parent ? Parent->getCanonicalDecl() : nullptr) {}
7118 bool ValidateCandidate(const TypoCorrection &candidate) override {
7119 if (candidate.getEditDistance() == 0)
7122 SmallVector<unsigned, 1> MismatchedParams;
7123 for (TypoCorrection::const_decl_iterator CDecl = candidate.begin(),
7124 CDeclEnd = candidate.end();
7125 CDecl != CDeclEnd; ++CDecl) {
7126 FunctionDecl *FD = dyn_cast<FunctionDecl>(*CDecl);
7128 if (FD && !FD->hasBody() &&
7129 hasSimilarParameters(Context, FD, OriginalFD, MismatchedParams)) {
7130 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) {
7131 CXXRecordDecl *Parent = MD->getParent();
7132 if (Parent && Parent->getCanonicalDecl() == ExpectedParent)
7134 } else if (!ExpectedParent) {
7144 ASTContext &Context;
7145 FunctionDecl *OriginalFD;
7146 CXXRecordDecl *ExpectedParent;
7149 } // end anonymous namespace
7151 /// \brief Generate diagnostics for an invalid function redeclaration.
7153 /// This routine handles generating the diagnostic messages for an invalid
7154 /// function redeclaration, including finding possible similar declarations
7155 /// or performing typo correction if there are no previous declarations with
7158 /// Returns a NamedDecl iff typo correction was performed and substituting in
7159 /// the new declaration name does not cause new errors.
7160 static NamedDecl *DiagnoseInvalidRedeclaration(
7161 Sema &SemaRef, LookupResult &Previous, FunctionDecl *NewFD,
7162 ActOnFDArgs &ExtraArgs, bool IsLocalFriend, Scope *S) {
7163 DeclarationName Name = NewFD->getDeclName();
7164 DeclContext *NewDC = NewFD->getDeclContext();
7165 SmallVector<unsigned, 1> MismatchedParams;
7166 SmallVector<std::pair<FunctionDecl *, unsigned>, 1> NearMatches;
7167 TypoCorrection Correction;
7168 bool IsDefinition = ExtraArgs.D.isFunctionDefinition();
7169 unsigned DiagMsg = IsLocalFriend ? diag::err_no_matching_local_friend
7170 : diag::err_member_decl_does_not_match;
7171 LookupResult Prev(SemaRef, Name, NewFD->getLocation(),
7172 IsLocalFriend ? Sema::LookupLocalFriendName
7173 : Sema::LookupOrdinaryName,
7174 Sema::ForRedeclaration);
7176 NewFD->setInvalidDecl();
7178 SemaRef.LookupName(Prev, S);
7180 SemaRef.LookupQualifiedName(Prev, NewDC);
7181 assert(!Prev.isAmbiguous() &&
7182 "Cannot have an ambiguity in previous-declaration lookup");
7183 CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(NewFD);
7184 if (!Prev.empty()) {
7185 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end();
7186 Func != FuncEnd; ++Func) {
7187 FunctionDecl *FD = dyn_cast<FunctionDecl>(*Func);
7189 hasSimilarParameters(SemaRef.Context, FD, NewFD, MismatchedParams)) {
7190 // Add 1 to the index so that 0 can mean the mismatch didn't
7191 // involve a parameter
7193 MismatchedParams.empty() ? 0 : MismatchedParams.front() + 1;
7194 NearMatches.push_back(std::make_pair(FD, ParamNum));
7197 // If the qualified name lookup yielded nothing, try typo correction
7198 } else if ((Correction = SemaRef.CorrectTypo(
7199 Prev.getLookupNameInfo(), Prev.getLookupKind(), S,
7200 &ExtraArgs.D.getCXXScopeSpec(),
7201 llvm::make_unique<DifferentNameValidatorCCC>(
7202 SemaRef.Context, NewFD, MD ? MD->getParent() : nullptr),
7203 Sema::CTK_ErrorRecovery, IsLocalFriend ? nullptr : NewDC))) {
7204 // Set up everything for the call to ActOnFunctionDeclarator
7205 ExtraArgs.D.SetIdentifier(Correction.getCorrectionAsIdentifierInfo(),
7206 ExtraArgs.D.getIdentifierLoc());
7208 Previous.setLookupName(Correction.getCorrection());
7209 for (TypoCorrection::decl_iterator CDecl = Correction.begin(),
7210 CDeclEnd = Correction.end();
7211 CDecl != CDeclEnd; ++CDecl) {
7212 FunctionDecl *FD = dyn_cast<FunctionDecl>(*CDecl);
7213 if (FD && !FD->hasBody() &&
7214 hasSimilarParameters(SemaRef.Context, FD, NewFD, MismatchedParams)) {
7215 Previous.addDecl(FD);
7218 bool wasRedeclaration = ExtraArgs.D.isRedeclaration();
7221 // Retry building the function declaration with the new previous
7222 // declarations, and with errors suppressed.
7225 Sema::SFINAETrap Trap(SemaRef);
7227 // TODO: Refactor ActOnFunctionDeclarator so that we can call only the
7228 // pieces need to verify the typo-corrected C++ declaration and hopefully
7229 // eliminate the need for the parameter pack ExtraArgs.
7230 Result = SemaRef.ActOnFunctionDeclarator(
7231 ExtraArgs.S, ExtraArgs.D,
7232 Correction.getCorrectionDecl()->getDeclContext(),
7233 NewFD->getTypeSourceInfo(), Previous, ExtraArgs.TemplateParamLists,
7234 ExtraArgs.AddToScope);
7236 if (Trap.hasErrorOccurred())
7241 // Determine which correction we picked.
7242 Decl *Canonical = Result->getCanonicalDecl();
7243 for (LookupResult::iterator I = Previous.begin(), E = Previous.end();
7245 if ((*I)->getCanonicalDecl() == Canonical)
7246 Correction.setCorrectionDecl(*I);
7248 SemaRef.diagnoseTypo(
7250 SemaRef.PDiag(IsLocalFriend
7251 ? diag::err_no_matching_local_friend_suggest
7252 : diag::err_member_decl_does_not_match_suggest)
7253 << Name << NewDC << IsDefinition);
7257 // Pretend the typo correction never occurred
7258 ExtraArgs.D.SetIdentifier(Name.getAsIdentifierInfo(),
7259 ExtraArgs.D.getIdentifierLoc());
7260 ExtraArgs.D.setRedeclaration(wasRedeclaration);
7262 Previous.setLookupName(Name);
7265 SemaRef.Diag(NewFD->getLocation(), DiagMsg)
7266 << Name << NewDC << IsDefinition << NewFD->getLocation();
7268 bool NewFDisConst = false;
7269 if (CXXMethodDecl *NewMD = dyn_cast<CXXMethodDecl>(NewFD))
7270 NewFDisConst = NewMD->isConst();
7272 for (SmallVectorImpl<std::pair<FunctionDecl *, unsigned> >::iterator
7273 NearMatch = NearMatches.begin(), NearMatchEnd = NearMatches.end();
7274 NearMatch != NearMatchEnd; ++NearMatch) {
7275 FunctionDecl *FD = NearMatch->first;
7276 CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD);
7277 bool FDisConst = MD && MD->isConst();
7278 bool IsMember = MD || !IsLocalFriend;
7280 // FIXME: These notes are poorly worded for the local friend case.
7281 if (unsigned Idx = NearMatch->second) {
7282 ParmVarDecl *FDParam = FD->getParamDecl(Idx-1);
7283 SourceLocation Loc = FDParam->getTypeSpecStartLoc();
7284 if (Loc.isInvalid()) Loc = FD->getLocation();
7285 SemaRef.Diag(Loc, IsMember ? diag::note_member_def_close_param_match
7286 : diag::note_local_decl_close_param_match)
7287 << Idx << FDParam->getType()
7288 << NewFD->getParamDecl(Idx - 1)->getType();
7289 } else if (FDisConst != NewFDisConst) {
7290 SemaRef.Diag(FD->getLocation(), diag::note_member_def_close_const_match)
7291 << NewFDisConst << FD->getSourceRange().getEnd();
7293 SemaRef.Diag(FD->getLocation(),
7294 IsMember ? diag::note_member_def_close_match
7295 : diag::note_local_decl_close_match);
7300 static StorageClass getFunctionStorageClass(Sema &SemaRef, Declarator &D) {
7301 switch (D.getDeclSpec().getStorageClassSpec()) {
7302 default: llvm_unreachable("Unknown storage class!");
7303 case DeclSpec::SCS_auto:
7304 case DeclSpec::SCS_register:
7305 case DeclSpec::SCS_mutable:
7306 SemaRef.Diag(D.getDeclSpec().getStorageClassSpecLoc(),
7307 diag::err_typecheck_sclass_func);
7310 case DeclSpec::SCS_unspecified: break;
7311 case DeclSpec::SCS_extern:
7312 if (D.getDeclSpec().isExternInLinkageSpec())
7315 case DeclSpec::SCS_static: {
7316 if (SemaRef.CurContext->getRedeclContext()->isFunctionOrMethod()) {
7318 // The declaration of an identifier for a function that has
7319 // block scope shall have no explicit storage-class specifier
7320 // other than extern
7321 // See also (C++ [dcl.stc]p4).
7322 SemaRef.Diag(D.getDeclSpec().getStorageClassSpecLoc(),
7323 diag::err_static_block_func);
7328 case DeclSpec::SCS_private_extern: return SC_PrivateExtern;
7331 // No explicit storage class has already been returned
7335 static FunctionDecl* CreateNewFunctionDecl(Sema &SemaRef, Declarator &D,
7336 DeclContext *DC, QualType &R,
7337 TypeSourceInfo *TInfo,
7339 bool &IsVirtualOkay) {
7340 DeclarationNameInfo NameInfo = SemaRef.GetNameForDeclarator(D);
7341 DeclarationName Name = NameInfo.getName();
7343 FunctionDecl *NewFD = nullptr;
7344 bool isInline = D.getDeclSpec().isInlineSpecified();
7346 if (!SemaRef.getLangOpts().CPlusPlus) {
7347 // Determine whether the function was written with a
7348 // prototype. This true when:
7349 // - there is a prototype in the declarator, or
7350 // - the type R of the function is some kind of typedef or other reference
7351 // to a type name (which eventually refers to a function type).
7353 (D.isFunctionDeclarator() && D.getFunctionTypeInfo().hasPrototype) ||
7354 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType());
7356 NewFD = FunctionDecl::Create(SemaRef.Context, DC,
7357 D.getLocStart(), NameInfo, R,
7358 TInfo, SC, isInline,
7359 HasPrototype, false);
7360 if (D.isInvalidType())
7361 NewFD->setInvalidDecl();
7366 bool isExplicit = D.getDeclSpec().isExplicitSpecified();
7367 bool isConstexpr = D.getDeclSpec().isConstexprSpecified();
7369 // Check that the return type is not an abstract class type.
7370 // For record types, this is done by the AbstractClassUsageDiagnoser once
7371 // the class has been completely parsed.
7372 if (!DC->isRecord() &&
7373 SemaRef.RequireNonAbstractType(
7374 D.getIdentifierLoc(), R->getAs<FunctionType>()->getReturnType(),
7375 diag::err_abstract_type_in_decl, SemaRef.AbstractReturnType))
7378 if (Name.getNameKind() == DeclarationName::CXXConstructorName) {
7379 // This is a C++ constructor declaration.
7380 assert(DC->isRecord() &&
7381 "Constructors can only be declared in a member context");
7383 R = SemaRef.CheckConstructorDeclarator(D, R, SC);
7384 return CXXConstructorDecl::Create(SemaRef.Context, cast<CXXRecordDecl>(DC),
7385 D.getLocStart(), NameInfo,
7386 R, TInfo, isExplicit, isInline,
7387 /*isImplicitlyDeclared=*/false,
7390 } else if (Name.getNameKind() == DeclarationName::CXXDestructorName) {
7391 // This is a C++ destructor declaration.
7392 if (DC->isRecord()) {
7393 R = SemaRef.CheckDestructorDeclarator(D, R, SC);
7394 CXXRecordDecl *Record = cast<CXXRecordDecl>(DC);
7395 CXXDestructorDecl *NewDD = CXXDestructorDecl::Create(
7396 SemaRef.Context, Record,
7398 NameInfo, R, TInfo, isInline,
7399 /*isImplicitlyDeclared=*/false);
7401 // If the class is complete, then we now create the implicit exception
7402 // specification. If the class is incomplete or dependent, we can't do
7404 if (SemaRef.getLangOpts().CPlusPlus11 && !Record->isDependentType() &&
7405 Record->getDefinition() && !Record->isBeingDefined() &&
7406 R->getAs<FunctionProtoType>()->getExceptionSpecType() == EST_None) {
7407 SemaRef.AdjustDestructorExceptionSpec(Record, NewDD);
7410 IsVirtualOkay = true;
7414 SemaRef.Diag(D.getIdentifierLoc(), diag::err_destructor_not_member);
7417 // Create a FunctionDecl to satisfy the function definition parsing
7419 return FunctionDecl::Create(SemaRef.Context, DC,
7421 D.getIdentifierLoc(), Name, R, TInfo,
7423 /*hasPrototype=*/true, isConstexpr);
7426 } else if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName) {
7427 if (!DC->isRecord()) {
7428 SemaRef.Diag(D.getIdentifierLoc(),
7429 diag::err_conv_function_not_member);
7433 SemaRef.CheckConversionDeclarator(D, R, SC);
7434 IsVirtualOkay = true;
7435 return CXXConversionDecl::Create(SemaRef.Context, cast<CXXRecordDecl>(DC),
7436 D.getLocStart(), NameInfo,
7437 R, TInfo, isInline, isExplicit,
7438 isConstexpr, SourceLocation());
7440 } else if (DC->isRecord()) {
7441 // If the name of the function is the same as the name of the record,
7442 // then this must be an invalid constructor that has a return type.
7443 // (The parser checks for a return type and makes the declarator a
7444 // constructor if it has no return type).
7445 if (Name.getAsIdentifierInfo() &&
7446 Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){
7447 SemaRef.Diag(D.getIdentifierLoc(), diag::err_constructor_return_type)
7448 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc())
7449 << SourceRange(D.getIdentifierLoc());
7453 // This is a C++ method declaration.
7454 CXXMethodDecl *Ret = CXXMethodDecl::Create(SemaRef.Context,
7455 cast<CXXRecordDecl>(DC),
7456 D.getLocStart(), NameInfo, R,
7457 TInfo, SC, isInline,
7458 isConstexpr, SourceLocation());
7459 IsVirtualOkay = !Ret->isStatic();
7463 SemaRef.getLangOpts().CPlusPlus && D.getDeclSpec().isFriendSpecified();
7464 if (!isFriend && SemaRef.CurContext->isRecord())
7467 // Determine whether the function was written with a
7468 // prototype. This true when:
7469 // - we're in C++ (where every function has a prototype),
7470 return FunctionDecl::Create(SemaRef.Context, DC,
7472 NameInfo, R, TInfo, SC, isInline,
7473 true/*HasPrototype*/, isConstexpr);
7477 enum OpenCLParamType {
7481 PrivatePtrKernelParam,
7486 static OpenCLParamType getOpenCLKernelParameterType(QualType PT) {
7487 if (PT->isPointerType()) {
7488 QualType PointeeType = PT->getPointeeType();
7489 if (PointeeType->isPointerType())
7490 return PtrPtrKernelParam;
7491 return PointeeType.getAddressSpace() == 0 ? PrivatePtrKernelParam
7495 // TODO: Forbid the other integer types (size_t, ptrdiff_t...) when they can
7496 // be used as builtin types.
7498 if (PT->isImageType())
7499 return PtrKernelParam;
7501 if (PT->isBooleanType())
7502 return InvalidKernelParam;
7505 return InvalidKernelParam;
7507 if (PT->isHalfType())
7508 return InvalidKernelParam;
7510 if (PT->isRecordType())
7511 return RecordKernelParam;
7513 return ValidKernelParam;
7516 static void checkIsValidOpenCLKernelParameter(
7520 llvm::SmallPtrSetImpl<const Type *> &ValidTypes) {
7521 QualType PT = Param->getType();
7523 // Cache the valid types we encounter to avoid rechecking structs that are
7525 if (ValidTypes.count(PT.getTypePtr()))
7528 switch (getOpenCLKernelParameterType(PT)) {
7529 case PtrPtrKernelParam:
7530 // OpenCL v1.2 s6.9.a:
7531 // A kernel function argument cannot be declared as a
7532 // pointer to a pointer type.
7533 S.Diag(Param->getLocation(), diag::err_opencl_ptrptr_kernel_param);
7537 case PrivatePtrKernelParam:
7538 // OpenCL v1.2 s6.9.a:
7539 // A kernel function argument cannot be declared as a
7540 // pointer to the private address space.
7541 S.Diag(Param->getLocation(), diag::err_opencl_private_ptr_kernel_param);
7545 // OpenCL v1.2 s6.9.k:
7546 // Arguments to kernel functions in a program cannot be declared with the
7547 // built-in scalar types bool, half, size_t, ptrdiff_t, intptr_t, and
7548 // uintptr_t or a struct and/or union that contain fields declared to be
7549 // one of these built-in scalar types.
7551 case InvalidKernelParam:
7552 // OpenCL v1.2 s6.8 n:
7553 // A kernel function argument cannot be declared
7555 S.Diag(Param->getLocation(), diag::err_bad_kernel_param_type) << PT;
7559 case PtrKernelParam:
7560 case ValidKernelParam:
7561 ValidTypes.insert(PT.getTypePtr());
7564 case RecordKernelParam:
7568 // Track nested structs we will inspect
7569 SmallVector<const Decl *, 4> VisitStack;
7571 // Track where we are in the nested structs. Items will migrate from
7572 // VisitStack to HistoryStack as we do the DFS for bad field.
7573 SmallVector<const FieldDecl *, 4> HistoryStack;
7574 HistoryStack.push_back(nullptr);
7576 const RecordDecl *PD = PT->castAs<RecordType>()->getDecl();
7577 VisitStack.push_back(PD);
7579 assert(VisitStack.back() && "First decl null?");
7582 const Decl *Next = VisitStack.pop_back_val();
7584 assert(!HistoryStack.empty());
7585 // Found a marker, we have gone up a level
7586 if (const FieldDecl *Hist = HistoryStack.pop_back_val())
7587 ValidTypes.insert(Hist->getType().getTypePtr());
7592 // Adds everything except the original parameter declaration (which is not a
7593 // field itself) to the history stack.
7594 const RecordDecl *RD;
7595 if (const FieldDecl *Field = dyn_cast<FieldDecl>(Next)) {
7596 HistoryStack.push_back(Field);
7597 RD = Field->getType()->castAs<RecordType>()->getDecl();
7599 RD = cast<RecordDecl>(Next);
7602 // Add a null marker so we know when we've gone back up a level
7603 VisitStack.push_back(nullptr);
7605 for (const auto *FD : RD->fields()) {
7606 QualType QT = FD->getType();
7608 if (ValidTypes.count(QT.getTypePtr()))
7611 OpenCLParamType ParamType = getOpenCLKernelParameterType(QT);
7612 if (ParamType == ValidKernelParam)
7615 if (ParamType == RecordKernelParam) {
7616 VisitStack.push_back(FD);
7620 // OpenCL v1.2 s6.9.p:
7621 // Arguments to kernel functions that are declared to be a struct or union
7622 // do not allow OpenCL objects to be passed as elements of the struct or
7624 if (ParamType == PtrKernelParam || ParamType == PtrPtrKernelParam ||
7625 ParamType == PrivatePtrKernelParam) {
7626 S.Diag(Param->getLocation(),
7627 diag::err_record_with_pointers_kernel_param)
7628 << PT->isUnionType()
7631 S.Diag(Param->getLocation(), diag::err_bad_kernel_param_type) << PT;
7634 S.Diag(PD->getLocation(), diag::note_within_field_of_type)
7635 << PD->getDeclName();
7637 // We have an error, now let's go back up through history and show where
7638 // the offending field came from
7639 for (ArrayRef<const FieldDecl *>::const_iterator
7640 I = HistoryStack.begin() + 1,
7641 E = HistoryStack.end();
7643 const FieldDecl *OuterField = *I;
7644 S.Diag(OuterField->getLocation(), diag::note_within_field_of_type)
7645 << OuterField->getType();
7648 S.Diag(FD->getLocation(), diag::note_illegal_field_declared_here)
7649 << QT->isPointerType()
7654 } while (!VisitStack.empty());
7658 Sema::ActOnFunctionDeclarator(Scope *S, Declarator &D, DeclContext *DC,
7659 TypeSourceInfo *TInfo, LookupResult &Previous,
7660 MultiTemplateParamsArg TemplateParamLists,
7662 QualType R = TInfo->getType();
7664 assert(R.getTypePtr()->isFunctionType());
7666 // TODO: consider using NameInfo for diagnostic.
7667 DeclarationNameInfo NameInfo = GetNameForDeclarator(D);
7668 DeclarationName Name = NameInfo.getName();
7669 StorageClass SC = getFunctionStorageClass(*this, D);
7671 if (DeclSpec::TSCS TSCS = D.getDeclSpec().getThreadStorageClassSpec())
7672 Diag(D.getDeclSpec().getThreadStorageClassSpecLoc(),
7673 diag::err_invalid_thread)
7674 << DeclSpec::getSpecifierName(TSCS);
7676 if (D.isFirstDeclarationOfMember())
7677 adjustMemberFunctionCC(R, D.isStaticMember(), D.isCtorOrDtor(),
7678 D.getIdentifierLoc());
7680 bool isFriend = false;
7681 FunctionTemplateDecl *FunctionTemplate = nullptr;
7682 bool isExplicitSpecialization = false;
7683 bool isFunctionTemplateSpecialization = false;
7685 bool isDependentClassScopeExplicitSpecialization = false;
7686 bool HasExplicitTemplateArgs = false;
7687 TemplateArgumentListInfo TemplateArgs;
7689 bool isVirtualOkay = false;
7691 DeclContext *OriginalDC = DC;
7692 bool IsLocalExternDecl = adjustContextForLocalExternDecl(DC);
7694 FunctionDecl *NewFD = CreateNewFunctionDecl(*this, D, DC, R, TInfo, SC,
7696 if (!NewFD) return nullptr;
7698 if (OriginalLexicalContext && OriginalLexicalContext->isObjCContainer())
7699 NewFD->setTopLevelDeclInObjCContainer();
7701 // Set the lexical context. If this is a function-scope declaration, or has a
7702 // C++ scope specifier, or is the object of a friend declaration, the lexical
7703 // context will be different from the semantic context.
7704 NewFD->setLexicalDeclContext(CurContext);
7706 if (IsLocalExternDecl)
7707 NewFD->setLocalExternDecl();
7709 if (getLangOpts().CPlusPlus) {
7710 bool isInline = D.getDeclSpec().isInlineSpecified();
7711 bool isVirtual = D.getDeclSpec().isVirtualSpecified();
7712 bool isExplicit = D.getDeclSpec().isExplicitSpecified();
7713 bool isConstexpr = D.getDeclSpec().isConstexprSpecified();
7714 bool isConcept = D.getDeclSpec().isConceptSpecified();
7715 isFriend = D.getDeclSpec().isFriendSpecified();
7716 if (isFriend && !isInline && D.isFunctionDefinition()) {
7717 // C++ [class.friend]p5
7718 // A function can be defined in a friend declaration of a
7719 // class . . . . Such a function is implicitly inline.
7720 NewFD->setImplicitlyInline();
7723 // If this is a method defined in an __interface, and is not a constructor
7724 // or an overloaded operator, then set the pure flag (isVirtual will already
7726 if (const CXXRecordDecl *Parent =
7727 dyn_cast<CXXRecordDecl>(NewFD->getDeclContext())) {
7728 if (Parent->isInterface() && cast<CXXMethodDecl>(NewFD)->isUserProvided())
7729 NewFD->setPure(true);
7731 // C++ [class.union]p2
7732 // A union can have member functions, but not virtual functions.
7733 if (isVirtual && Parent->isUnion())
7734 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_in_union);
7737 SetNestedNameSpecifier(NewFD, D);
7738 isExplicitSpecialization = false;
7739 isFunctionTemplateSpecialization = false;
7740 if (D.isInvalidType())
7741 NewFD->setInvalidDecl();
7743 // Match up the template parameter lists with the scope specifier, then
7744 // determine whether we have a template or a template specialization.
7745 bool Invalid = false;
7746 if (TemplateParameterList *TemplateParams =
7747 MatchTemplateParametersToScopeSpecifier(
7748 D.getDeclSpec().getLocStart(), D.getIdentifierLoc(),
7749 D.getCXXScopeSpec(),
7750 D.getName().getKind() == UnqualifiedId::IK_TemplateId
7751 ? D.getName().TemplateId
7753 TemplateParamLists, isFriend, isExplicitSpecialization,
7755 if (TemplateParams->size() > 0) {
7756 // This is a function template
7758 // Check that we can declare a template here.
7759 if (CheckTemplateDeclScope(S, TemplateParams))
7760 NewFD->setInvalidDecl();
7762 // A destructor cannot be a template.
7763 if (Name.getNameKind() == DeclarationName::CXXDestructorName) {
7764 Diag(NewFD->getLocation(), diag::err_destructor_template);
7765 NewFD->setInvalidDecl();
7768 // If we're adding a template to a dependent context, we may need to
7769 // rebuilding some of the types used within the template parameter list,
7770 // now that we know what the current instantiation is.
7771 if (DC->isDependentContext()) {
7772 ContextRAII SavedContext(*this, DC);
7773 if (RebuildTemplateParamsInCurrentInstantiation(TemplateParams))
7777 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC,
7778 NewFD->getLocation(),
7779 Name, TemplateParams,
7781 FunctionTemplate->setLexicalDeclContext(CurContext);
7782 NewFD->setDescribedFunctionTemplate(FunctionTemplate);
7784 // For source fidelity, store the other template param lists.
7785 if (TemplateParamLists.size() > 1) {
7786 NewFD->setTemplateParameterListsInfo(Context,
7787 TemplateParamLists.drop_back(1));
7790 // This is a function template specialization.
7791 isFunctionTemplateSpecialization = true;
7792 // For source fidelity, store all the template param lists.
7793 if (TemplateParamLists.size() > 0)
7794 NewFD->setTemplateParameterListsInfo(Context, TemplateParamLists);
7796 // C++0x [temp.expl.spec]p20 forbids "template<> friend void foo(int);".
7798 // We want to remove the "template<>", found here.
7799 SourceRange RemoveRange = TemplateParams->getSourceRange();
7801 // If we remove the template<> and the name is not a
7802 // template-id, we're actually silently creating a problem:
7803 // the friend declaration will refer to an untemplated decl,
7804 // and clearly the user wants a template specialization. So
7805 // we need to insert '<>' after the name.
7806 SourceLocation InsertLoc;
7807 if (D.getName().getKind() != UnqualifiedId::IK_TemplateId) {
7808 InsertLoc = D.getName().getSourceRange().getEnd();
7809 InsertLoc = getLocForEndOfToken(InsertLoc);
7812 Diag(D.getIdentifierLoc(), diag::err_template_spec_decl_friend)
7813 << Name << RemoveRange
7814 << FixItHint::CreateRemoval(RemoveRange)
7815 << FixItHint::CreateInsertion(InsertLoc, "<>");
7820 // All template param lists were matched against the scope specifier:
7821 // this is NOT (an explicit specialization of) a template.
7822 if (TemplateParamLists.size() > 0)
7823 // For source fidelity, store all the template param lists.
7824 NewFD->setTemplateParameterListsInfo(Context, TemplateParamLists);
7828 NewFD->setInvalidDecl();
7829 if (FunctionTemplate)
7830 FunctionTemplate->setInvalidDecl();
7833 // C++ [dcl.fct.spec]p5:
7834 // The virtual specifier shall only be used in declarations of
7835 // nonstatic class member functions that appear within a
7836 // member-specification of a class declaration; see 10.3.
7838 if (isVirtual && !NewFD->isInvalidDecl()) {
7839 if (!isVirtualOkay) {
7840 Diag(D.getDeclSpec().getVirtualSpecLoc(),
7841 diag::err_virtual_non_function);
7842 } else if (!CurContext->isRecord()) {
7843 // 'virtual' was specified outside of the class.
7844 Diag(D.getDeclSpec().getVirtualSpecLoc(),
7845 diag::err_virtual_out_of_class)
7846 << FixItHint::CreateRemoval(D.getDeclSpec().getVirtualSpecLoc());
7847 } else if (NewFD->getDescribedFunctionTemplate()) {
7848 // C++ [temp.mem]p3:
7849 // A member function template shall not be virtual.
7850 Diag(D.getDeclSpec().getVirtualSpecLoc(),
7851 diag::err_virtual_member_function_template)
7852 << FixItHint::CreateRemoval(D.getDeclSpec().getVirtualSpecLoc());
7854 // Okay: Add virtual to the method.
7855 NewFD->setVirtualAsWritten(true);
7858 if (getLangOpts().CPlusPlus14 &&
7859 NewFD->getReturnType()->isUndeducedType())
7860 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_auto_fn_virtual);
7863 if (getLangOpts().CPlusPlus14 &&
7864 (NewFD->isDependentContext() ||
7865 (isFriend && CurContext->isDependentContext())) &&
7866 NewFD->getReturnType()->isUndeducedType()) {
7867 // If the function template is referenced directly (for instance, as a
7868 // member of the current instantiation), pretend it has a dependent type.
7869 // This is not really justified by the standard, but is the only sane
7871 // FIXME: For a friend function, we have not marked the function as being
7872 // a friend yet, so 'isDependentContext' on the FD doesn't work.
7873 const FunctionProtoType *FPT =
7874 NewFD->getType()->castAs<FunctionProtoType>();
7876 SubstAutoType(FPT->getReturnType(), Context.DependentTy);
7877 NewFD->setType(Context.getFunctionType(Result, FPT->getParamTypes(),
7878 FPT->getExtProtoInfo()));
7881 // C++ [dcl.fct.spec]p3:
7882 // The inline specifier shall not appear on a block scope function
7884 if (isInline && !NewFD->isInvalidDecl()) {
7885 if (CurContext->isFunctionOrMethod()) {
7886 // 'inline' is not allowed on block scope function declaration.
7887 Diag(D.getDeclSpec().getInlineSpecLoc(),
7888 diag::err_inline_declaration_block_scope) << Name
7889 << FixItHint::CreateRemoval(D.getDeclSpec().getInlineSpecLoc());
7893 // C++ [dcl.fct.spec]p6:
7894 // The explicit specifier shall be used only in the declaration of a
7895 // constructor or conversion function within its class definition;
7896 // see 12.3.1 and 12.3.2.
7897 if (isExplicit && !NewFD->isInvalidDecl()) {
7898 if (!CurContext->isRecord()) {
7899 // 'explicit' was specified outside of the class.
7900 Diag(D.getDeclSpec().getExplicitSpecLoc(),
7901 diag::err_explicit_out_of_class)
7902 << FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecLoc());
7903 } else if (!isa<CXXConstructorDecl>(NewFD) &&
7904 !isa<CXXConversionDecl>(NewFD)) {
7905 // 'explicit' was specified on a function that wasn't a constructor
7906 // or conversion function.
7907 Diag(D.getDeclSpec().getExplicitSpecLoc(),
7908 diag::err_explicit_non_ctor_or_conv_function)
7909 << FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecLoc());
7914 // C++11 [dcl.constexpr]p2: constexpr functions and constexpr constructors
7915 // are implicitly inline.
7916 NewFD->setImplicitlyInline();
7918 // C++11 [dcl.constexpr]p3: functions declared constexpr are required to
7919 // be either constructors or to return a literal type. Therefore,
7920 // destructors cannot be declared constexpr.
7921 if (isa<CXXDestructorDecl>(NewFD))
7922 Diag(D.getDeclSpec().getConstexprSpecLoc(), diag::err_constexpr_dtor);
7926 // This is a function concept.
7927 if (FunctionTemplateDecl *FTD = NewFD->getDescribedFunctionTemplate())
7930 // C++ Concepts TS [dcl.spec.concept]p1: The concept specifier shall be
7931 // applied only to the definition of a function template [...]
7932 if (!D.isFunctionDefinition()) {
7933 Diag(D.getDeclSpec().getConceptSpecLoc(),
7934 diag::err_function_concept_not_defined);
7935 NewFD->setInvalidDecl();
7938 // C++ Concepts TS [dcl.spec.concept]p1: [...] A function concept shall
7939 // have no exception-specification and is treated as if it were specified
7940 // with noexcept(true) (15.4). [...]
7941 if (const FunctionProtoType *FPT = R->getAs<FunctionProtoType>()) {
7942 if (FPT->hasExceptionSpec()) {
7944 if (D.isFunctionDeclarator())
7945 Range = D.getFunctionTypeInfo().getExceptionSpecRange();
7946 Diag(NewFD->getLocation(), diag::err_function_concept_exception_spec)
7947 << FixItHint::CreateRemoval(Range);
7948 NewFD->setInvalidDecl();
7950 Context.adjustExceptionSpec(NewFD, EST_BasicNoexcept);
7953 // C++ Concepts TS [dcl.spec.concept]p5: A function concept has the
7954 // following restrictions:
7955 // - The declared return type shall have the type bool.
7956 if (!Context.hasSameType(FPT->getReturnType(), Context.BoolTy)) {
7957 Diag(D.getIdentifierLoc(), diag::err_function_concept_bool_ret);
7958 NewFD->setInvalidDecl();
7961 // C++ Concepts TS [dcl.spec.concept]p5: A function concept has the
7962 // following restrictions:
7963 // - The declaration's parameter list shall be equivalent to an empty
7965 if (FPT->getNumParams() > 0 || FPT->isVariadic())
7966 Diag(NewFD->getLocation(), diag::err_function_concept_with_params);
7969 // C++ Concepts TS [dcl.spec.concept]p2: Every concept definition is
7970 // implicity defined to be a constexpr declaration (implicitly inline)
7971 NewFD->setImplicitlyInline();
7973 // C++ Concepts TS [dcl.spec.concept]p2: A concept definition shall not
7974 // be declared with the thread_local, inline, friend, or constexpr
7975 // specifiers, [...]
7977 Diag(D.getDeclSpec().getInlineSpecLoc(),
7978 diag::err_concept_decl_invalid_specifiers)
7980 NewFD->setInvalidDecl(true);
7984 Diag(D.getDeclSpec().getFriendSpecLoc(),
7985 diag::err_concept_decl_invalid_specifiers)
7987 NewFD->setInvalidDecl(true);
7991 Diag(D.getDeclSpec().getConstexprSpecLoc(),
7992 diag::err_concept_decl_invalid_specifiers)
7994 NewFD->setInvalidDecl(true);
7997 // C++ Concepts TS [dcl.spec.concept]p1: The concept specifier shall be
7998 // applied only to the definition of a function template or variable
7999 // template, declared in namespace scope.
8000 if (isFunctionTemplateSpecialization) {
8001 Diag(D.getDeclSpec().getConceptSpecLoc(),
8002 diag::err_concept_specified_specialization) << 1;
8003 NewFD->setInvalidDecl(true);
8008 // If __module_private__ was specified, mark the function accordingly.
8009 if (D.getDeclSpec().isModulePrivateSpecified()) {
8010 if (isFunctionTemplateSpecialization) {
8011 SourceLocation ModulePrivateLoc
8012 = D.getDeclSpec().getModulePrivateSpecLoc();
8013 Diag(ModulePrivateLoc, diag::err_module_private_specialization)
8015 << FixItHint::CreateRemoval(ModulePrivateLoc);
8017 NewFD->setModulePrivate();
8018 if (FunctionTemplate)
8019 FunctionTemplate->setModulePrivate();
8024 if (FunctionTemplate) {
8025 FunctionTemplate->setObjectOfFriendDecl();
8026 FunctionTemplate->setAccess(AS_public);
8028 NewFD->setObjectOfFriendDecl();
8029 NewFD->setAccess(AS_public);
8032 // If a function is defined as defaulted or deleted, mark it as such now.
8033 // FIXME: Does this ever happen? ActOnStartOfFunctionDef forces the function
8034 // definition kind to FDK_Definition.
8035 switch (D.getFunctionDefinitionKind()) {
8036 case FDK_Declaration:
8037 case FDK_Definition:
8041 NewFD->setDefaulted();
8045 NewFD->setDeletedAsWritten();
8049 if (isa<CXXMethodDecl>(NewFD) && DC == CurContext &&
8050 D.isFunctionDefinition()) {
8051 // C++ [class.mfct]p2:
8052 // A member function may be defined (8.4) in its class definition, in
8053 // which case it is an inline member function (7.1.2)
8054 NewFD->setImplicitlyInline();
8057 if (SC == SC_Static && isa<CXXMethodDecl>(NewFD) &&
8058 !CurContext->isRecord()) {
8059 // C++ [class.static]p1:
8060 // A data or function member of a class may be declared static
8061 // in a class definition, in which case it is a static member of
8064 // Complain about the 'static' specifier if it's on an out-of-line
8065 // member function definition.
8066 Diag(D.getDeclSpec().getStorageClassSpecLoc(),
8067 diag::err_static_out_of_line)
8068 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc());
8071 // C++11 [except.spec]p15:
8072 // A deallocation function with no exception-specification is treated
8073 // as if it were specified with noexcept(true).
8074 const FunctionProtoType *FPT = R->getAs<FunctionProtoType>();
8075 if ((Name.getCXXOverloadedOperator() == OO_Delete ||
8076 Name.getCXXOverloadedOperator() == OO_Array_Delete) &&
8077 getLangOpts().CPlusPlus11 && FPT && !FPT->hasExceptionSpec())
8078 NewFD->setType(Context.getFunctionType(
8079 FPT->getReturnType(), FPT->getParamTypes(),
8080 FPT->getExtProtoInfo().withExceptionSpec(EST_BasicNoexcept)));
8083 // Filter out previous declarations that don't match the scope.
8084 FilterLookupForScope(Previous, OriginalDC, S, shouldConsiderLinkage(NewFD),
8085 D.getCXXScopeSpec().isNotEmpty() ||
8086 isExplicitSpecialization ||
8087 isFunctionTemplateSpecialization);
8089 // Handle GNU asm-label extension (encoded as an attribute).
8090 if (Expr *E = (Expr*) D.getAsmLabel()) {
8091 // The parser guarantees this is a string.
8092 StringLiteral *SE = cast<StringLiteral>(E);
8093 NewFD->addAttr(::new (Context) AsmLabelAttr(SE->getStrTokenLoc(0), Context,
8094 SE->getString(), 0));
8095 } else if (!ExtnameUndeclaredIdentifiers.empty()) {
8096 llvm::DenseMap<IdentifierInfo*,AsmLabelAttr*>::iterator I =
8097 ExtnameUndeclaredIdentifiers.find(NewFD->getIdentifier());
8098 if (I != ExtnameUndeclaredIdentifiers.end()) {
8099 if (isDeclExternC(NewFD)) {
8100 NewFD->addAttr(I->second);
8101 ExtnameUndeclaredIdentifiers.erase(I);
8103 Diag(NewFD->getLocation(), diag::warn_redefine_extname_not_applied)
8104 << /*Variable*/0 << NewFD;
8108 // Copy the parameter declarations from the declarator D to the function
8109 // declaration NewFD, if they are available. First scavenge them into Params.
8110 SmallVector<ParmVarDecl*, 16> Params;
8111 if (D.isFunctionDeclarator()) {
8112 DeclaratorChunk::FunctionTypeInfo &FTI = D.getFunctionTypeInfo();
8114 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs
8115 // function that takes no arguments, not a function that takes a
8116 // single void argument.
8117 // We let through "const void" here because Sema::GetTypeForDeclarator
8118 // already checks for that case.
8119 if (FTIHasNonVoidParameters(FTI) && FTI.Params[0].Param) {
8120 for (unsigned i = 0, e = FTI.NumParams; i != e; ++i) {
8121 ParmVarDecl *Param = cast<ParmVarDecl>(FTI.Params[i].Param);
8122 assert(Param->getDeclContext() != NewFD && "Was set before ?");
8123 Param->setDeclContext(NewFD);
8124 Params.push_back(Param);
8126 if (Param->isInvalidDecl())
8127 NewFD->setInvalidDecl();
8130 } else if (const FunctionProtoType *FT = R->getAs<FunctionProtoType>()) {
8131 // When we're declaring a function with a typedef, typeof, etc as in the
8132 // following example, we'll need to synthesize (unnamed)
8133 // parameters for use in the declaration.
8136 // typedef void fn(int);
8140 // Synthesize a parameter for each argument type.
8141 for (const auto &AI : FT->param_types()) {
8142 ParmVarDecl *Param =
8143 BuildParmVarDeclForTypedef(NewFD, D.getIdentifierLoc(), AI);
8144 Param->setScopeInfo(0, Params.size());
8145 Params.push_back(Param);
8148 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 &&
8149 "Should not need args for typedef of non-prototype fn");
8152 // Finally, we know we have the right number of parameters, install them.
8153 NewFD->setParams(Params);
8155 // Find all anonymous symbols defined during the declaration of this function
8156 // and add to NewFD. This lets us track decls such 'enum Y' in:
8158 // void f(enum Y {AA} x) {}
8160 // which would otherwise incorrectly end up in the translation unit scope.
8161 NewFD->setDeclsInPrototypeScope(DeclsInPrototypeScope);
8162 DeclsInPrototypeScope.clear();
8164 if (D.getDeclSpec().isNoreturnSpecified())
8166 ::new(Context) C11NoReturnAttr(D.getDeclSpec().getNoreturnSpecLoc(),
8169 // Functions returning a variably modified type violate C99 6.7.5.2p2
8170 // because all functions have linkage.
8171 if (!NewFD->isInvalidDecl() &&
8172 NewFD->getReturnType()->isVariablyModifiedType()) {
8173 Diag(NewFD->getLocation(), diag::err_vm_func_decl);
8174 NewFD->setInvalidDecl();
8177 // Apply an implicit SectionAttr if #pragma code_seg is active.
8178 if (CodeSegStack.CurrentValue && D.isFunctionDefinition() &&
8179 !NewFD->hasAttr<SectionAttr>()) {
8181 SectionAttr::CreateImplicit(Context, SectionAttr::Declspec_allocate,
8182 CodeSegStack.CurrentValue->getString(),
8183 CodeSegStack.CurrentPragmaLocation));
8184 if (UnifySection(CodeSegStack.CurrentValue->getString(),
8185 ASTContext::PSF_Implicit | ASTContext::PSF_Execute |
8186 ASTContext::PSF_Read,
8188 NewFD->dropAttr<SectionAttr>();
8191 // Handle attributes.
8192 ProcessDeclAttributes(S, NewFD, D);
8194 if (getLangOpts().CUDA)
8195 maybeAddCUDAHostDeviceAttrs(S, NewFD, Previous);
8197 if (getLangOpts().OpenCL) {
8198 // OpenCL v1.1 s6.5: Using an address space qualifier in a function return
8199 // type declaration will generate a compilation error.
8200 unsigned AddressSpace = NewFD->getReturnType().getAddressSpace();
8201 if (AddressSpace == LangAS::opencl_local ||
8202 AddressSpace == LangAS::opencl_global ||
8203 AddressSpace == LangAS::opencl_constant) {
8204 Diag(NewFD->getLocation(),
8205 diag::err_opencl_return_value_with_address_space);
8206 NewFD->setInvalidDecl();
8210 if (!getLangOpts().CPlusPlus) {
8211 // Perform semantic checking on the function declaration.
8212 bool isExplicitSpecialization=false;
8213 if (!NewFD->isInvalidDecl() && NewFD->isMain())
8214 CheckMain(NewFD, D.getDeclSpec());
8216 if (!NewFD->isInvalidDecl() && NewFD->isMSVCRTEntryPoint())
8217 CheckMSVCRTEntryPoint(NewFD);
8219 if (!NewFD->isInvalidDecl())
8220 D.setRedeclaration(CheckFunctionDeclaration(S, NewFD, Previous,
8221 isExplicitSpecialization));
8222 else if (!Previous.empty())
8223 // Recover gracefully from an invalid redeclaration.
8224 D.setRedeclaration(true);
8225 assert((NewFD->isInvalidDecl() || !D.isRedeclaration() ||
8226 Previous.getResultKind() != LookupResult::FoundOverloaded) &&
8227 "previous declaration set still overloaded");
8229 // Diagnose no-prototype function declarations with calling conventions that
8230 // don't support variadic calls. Only do this in C and do it after merging
8231 // possibly prototyped redeclarations.
8232 const FunctionType *FT = NewFD->getType()->castAs<FunctionType>();
8233 if (isa<FunctionNoProtoType>(FT) && !D.isFunctionDefinition()) {
8234 CallingConv CC = FT->getExtInfo().getCC();
8235 if (!supportsVariadicCall(CC)) {
8236 // Windows system headers sometimes accidentally use stdcall without
8237 // (void) parameters, so we relax this to a warning.
8239 CC == CC_X86StdCall ? diag::warn_cconv_knr : diag::err_cconv_knr;
8240 Diag(NewFD->getLocation(), DiagID)
8241 << FunctionType::getNameForCallConv(CC);
8245 // C++11 [replacement.functions]p3:
8246 // The program's definitions shall not be specified as inline.
8248 // N.B. We diagnose declarations instead of definitions per LWG issue 2340.
8250 // Suppress the diagnostic if the function is __attribute__((used)), since
8251 // that forces an external definition to be emitted.
8252 if (D.getDeclSpec().isInlineSpecified() &&
8253 NewFD->isReplaceableGlobalAllocationFunction() &&
8254 !NewFD->hasAttr<UsedAttr>())
8255 Diag(D.getDeclSpec().getInlineSpecLoc(),
8256 diag::ext_operator_new_delete_declared_inline)
8257 << NewFD->getDeclName();
8259 // If the declarator is a template-id, translate the parser's template
8260 // argument list into our AST format.
8261 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) {
8262 TemplateIdAnnotation *TemplateId = D.getName().TemplateId;
8263 TemplateArgs.setLAngleLoc(TemplateId->LAngleLoc);
8264 TemplateArgs.setRAngleLoc(TemplateId->RAngleLoc);
8265 ASTTemplateArgsPtr TemplateArgsPtr(TemplateId->getTemplateArgs(),
8266 TemplateId->NumArgs);
8267 translateTemplateArguments(TemplateArgsPtr,
8270 HasExplicitTemplateArgs = true;
8272 if (NewFD->isInvalidDecl()) {
8273 HasExplicitTemplateArgs = false;
8274 } else if (FunctionTemplate) {
8275 // Function template with explicit template arguments.
8276 Diag(D.getIdentifierLoc(), diag::err_function_template_partial_spec)
8277 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc);
8279 HasExplicitTemplateArgs = false;
8281 assert((isFunctionTemplateSpecialization ||
8282 D.getDeclSpec().isFriendSpecified()) &&
8283 "should have a 'template<>' for this decl");
8284 // "friend void foo<>(int);" is an implicit specialization decl.
8285 isFunctionTemplateSpecialization = true;
8287 } else if (isFriend && isFunctionTemplateSpecialization) {
8288 // This combination is only possible in a recovery case; the user
8289 // wrote something like:
8290 // template <> friend void foo(int);
8291 // which we're recovering from as if the user had written:
8292 // friend void foo<>(int);
8293 // Go ahead and fake up a template id.
8294 HasExplicitTemplateArgs = true;
8295 TemplateArgs.setLAngleLoc(D.getIdentifierLoc());
8296 TemplateArgs.setRAngleLoc(D.getIdentifierLoc());
8299 // If it's a friend (and only if it's a friend), it's possible
8300 // that either the specialized function type or the specialized
8301 // template is dependent, and therefore matching will fail. In
8302 // this case, don't check the specialization yet.
8303 bool InstantiationDependent = false;
8304 if (isFunctionTemplateSpecialization && isFriend &&
8305 (NewFD->getType()->isDependentType() || DC->isDependentContext() ||
8306 TemplateSpecializationType::anyDependentTemplateArguments(
8308 InstantiationDependent))) {
8309 assert(HasExplicitTemplateArgs &&
8310 "friend function specialization without template args");
8311 if (CheckDependentFunctionTemplateSpecialization(NewFD, TemplateArgs,
8313 NewFD->setInvalidDecl();
8314 } else if (isFunctionTemplateSpecialization) {
8315 if (CurContext->isDependentContext() && CurContext->isRecord()
8317 isDependentClassScopeExplicitSpecialization = true;
8318 Diag(NewFD->getLocation(), getLangOpts().MicrosoftExt ?
8319 diag::ext_function_specialization_in_class :
8320 diag::err_function_specialization_in_class)
8321 << NewFD->getDeclName();
8322 } else if (CheckFunctionTemplateSpecialization(NewFD,
8323 (HasExplicitTemplateArgs ? &TemplateArgs
8326 NewFD->setInvalidDecl();
8329 // A storage-class-specifier shall not be specified in an explicit
8330 // specialization (14.7.3)
8331 FunctionTemplateSpecializationInfo *Info =
8332 NewFD->getTemplateSpecializationInfo();
8333 if (Info && SC != SC_None) {
8334 if (SC != Info->getTemplate()->getTemplatedDecl()->getStorageClass())
8335 Diag(NewFD->getLocation(),
8336 diag::err_explicit_specialization_inconsistent_storage_class)
8338 << FixItHint::CreateRemoval(
8339 D.getDeclSpec().getStorageClassSpecLoc());
8342 Diag(NewFD->getLocation(),
8343 diag::ext_explicit_specialization_storage_class)
8344 << FixItHint::CreateRemoval(
8345 D.getDeclSpec().getStorageClassSpecLoc());
8347 } else if (isExplicitSpecialization && isa<CXXMethodDecl>(NewFD)) {
8348 if (CheckMemberSpecialization(NewFD, Previous))
8349 NewFD->setInvalidDecl();
8352 // Perform semantic checking on the function declaration.
8353 if (!isDependentClassScopeExplicitSpecialization) {
8354 if (!NewFD->isInvalidDecl() && NewFD->isMain())
8355 CheckMain(NewFD, D.getDeclSpec());
8357 if (!NewFD->isInvalidDecl() && NewFD->isMSVCRTEntryPoint())
8358 CheckMSVCRTEntryPoint(NewFD);
8360 if (!NewFD->isInvalidDecl())
8361 D.setRedeclaration(CheckFunctionDeclaration(S, NewFD, Previous,
8362 isExplicitSpecialization));
8363 else if (!Previous.empty())
8364 // Recover gracefully from an invalid redeclaration.
8365 D.setRedeclaration(true);
8368 assert((NewFD->isInvalidDecl() || !D.isRedeclaration() ||
8369 Previous.getResultKind() != LookupResult::FoundOverloaded) &&
8370 "previous declaration set still overloaded");
8372 NamedDecl *PrincipalDecl = (FunctionTemplate
8373 ? cast<NamedDecl>(FunctionTemplate)
8376 if (isFriend && D.isRedeclaration()) {
8377 AccessSpecifier Access = AS_public;
8378 if (!NewFD->isInvalidDecl())
8379 Access = NewFD->getPreviousDecl()->getAccess();
8381 NewFD->setAccess(Access);
8382 if (FunctionTemplate) FunctionTemplate->setAccess(Access);
8385 if (NewFD->isOverloadedOperator() && !DC->isRecord() &&
8386 PrincipalDecl->isInIdentifierNamespace(Decl::IDNS_Ordinary))
8387 PrincipalDecl->setNonMemberOperator();
8389 // If we have a function template, check the template parameter
8390 // list. This will check and merge default template arguments.
8391 if (FunctionTemplate) {
8392 FunctionTemplateDecl *PrevTemplate =
8393 FunctionTemplate->getPreviousDecl();
8394 CheckTemplateParameterList(FunctionTemplate->getTemplateParameters(),
8395 PrevTemplate ? PrevTemplate->getTemplateParameters()
8397 D.getDeclSpec().isFriendSpecified()
8398 ? (D.isFunctionDefinition()
8399 ? TPC_FriendFunctionTemplateDefinition
8400 : TPC_FriendFunctionTemplate)
8401 : (D.getCXXScopeSpec().isSet() &&
8402 DC && DC->isRecord() &&
8403 DC->isDependentContext())
8404 ? TPC_ClassTemplateMember
8405 : TPC_FunctionTemplate);
8408 if (NewFD->isInvalidDecl()) {
8409 // Ignore all the rest of this.
8410 } else if (!D.isRedeclaration()) {
8411 struct ActOnFDArgs ExtraArgs = { S, D, TemplateParamLists,
8413 // Fake up an access specifier if it's supposed to be a class member.
8414 if (isa<CXXRecordDecl>(NewFD->getDeclContext()))
8415 NewFD->setAccess(AS_public);
8417 // Qualified decls generally require a previous declaration.
8418 if (D.getCXXScopeSpec().isSet()) {
8419 // ...with the major exception of templated-scope or
8420 // dependent-scope friend declarations.
8422 // TODO: we currently also suppress this check in dependent
8423 // contexts because (1) the parameter depth will be off when
8424 // matching friend templates and (2) we might actually be
8425 // selecting a friend based on a dependent factor. But there
8426 // are situations where these conditions don't apply and we
8427 // can actually do this check immediately.
8429 (TemplateParamLists.size() ||
8430 D.getCXXScopeSpec().getScopeRep()->isDependent() ||
8431 CurContext->isDependentContext())) {
8434 // The user tried to provide an out-of-line definition for a
8435 // function that is a member of a class or namespace, but there
8436 // was no such member function declared (C++ [class.mfct]p2,
8437 // C++ [namespace.memdef]p2). For example:
8443 // void X::f() { } // ill-formed
8445 // Complain about this problem, and attempt to suggest close
8446 // matches (e.g., those that differ only in cv-qualifiers and
8447 // whether the parameter types are references).
8449 if (NamedDecl *Result = DiagnoseInvalidRedeclaration(
8450 *this, Previous, NewFD, ExtraArgs, false, nullptr)) {
8451 AddToScope = ExtraArgs.AddToScope;
8456 // Unqualified local friend declarations are required to resolve
8458 } else if (isFriend && cast<CXXRecordDecl>(CurContext)->isLocalClass()) {
8459 if (NamedDecl *Result = DiagnoseInvalidRedeclaration(
8460 *this, Previous, NewFD, ExtraArgs, true, S)) {
8461 AddToScope = ExtraArgs.AddToScope;
8465 } else if (!D.isFunctionDefinition() &&
8466 isa<CXXMethodDecl>(NewFD) && NewFD->isOutOfLine() &&
8467 !isFriend && !isFunctionTemplateSpecialization &&
8468 !isExplicitSpecialization) {
8469 // An out-of-line member function declaration must also be a
8470 // definition (C++ [class.mfct]p2).
8471 // Note that this is not the case for explicit specializations of
8472 // function templates or member functions of class templates, per
8473 // C++ [temp.expl.spec]p2. We also allow these declarations as an
8474 // extension for compatibility with old SWIG code which likes to
8476 Diag(NewFD->getLocation(), diag::ext_out_of_line_declaration)
8477 << D.getCXXScopeSpec().getRange();
8481 ProcessPragmaWeak(S, NewFD);
8482 checkAttributesAfterMerging(*this, *NewFD);
8484 AddKnownFunctionAttributes(NewFD);
8486 if (NewFD->hasAttr<OverloadableAttr>() &&
8487 !NewFD->getType()->getAs<FunctionProtoType>()) {
8488 Diag(NewFD->getLocation(),
8489 diag::err_attribute_overloadable_no_prototype)
8492 // Turn this into a variadic function with no parameters.
8493 const FunctionType *FT = NewFD->getType()->getAs<FunctionType>();
8494 FunctionProtoType::ExtProtoInfo EPI(
8495 Context.getDefaultCallingConvention(true, false));
8496 EPI.Variadic = true;
8497 EPI.ExtInfo = FT->getExtInfo();
8499 QualType R = Context.getFunctionType(FT->getReturnType(), None, EPI);
8503 // If there's a #pragma GCC visibility in scope, and this isn't a class
8504 // member, set the visibility of this function.
8505 if (!DC->isRecord() && NewFD->isExternallyVisible())
8506 AddPushedVisibilityAttribute(NewFD);
8508 // If there's a #pragma clang arc_cf_code_audited in scope, consider
8509 // marking the function.
8510 AddCFAuditedAttribute(NewFD);
8512 // If this is a function definition, check if we have to apply optnone due to
8514 if(D.isFunctionDefinition())
8515 AddRangeBasedOptnone(NewFD);
8517 // If this is the first declaration of an extern C variable, update
8518 // the map of such variables.
8519 if (NewFD->isFirstDecl() && !NewFD->isInvalidDecl() &&
8520 isIncompleteDeclExternC(*this, NewFD))
8521 RegisterLocallyScopedExternCDecl(NewFD, S);
8523 // Set this FunctionDecl's range up to the right paren.
8524 NewFD->setRangeEnd(D.getSourceRange().getEnd());
8526 if (D.isRedeclaration() && !Previous.empty()) {
8527 checkDLLAttributeRedeclaration(
8528 *this, dyn_cast<NamedDecl>(Previous.getRepresentativeDecl()), NewFD,
8529 isExplicitSpecialization || isFunctionTemplateSpecialization,
8530 D.isFunctionDefinition());
8533 if (getLangOpts().CUDA) {
8534 IdentifierInfo *II = NewFD->getIdentifier();
8535 if (II && II->isStr("cudaConfigureCall") && !NewFD->isInvalidDecl() &&
8536 NewFD->getDeclContext()->getRedeclContext()->isTranslationUnit()) {
8537 if (!R->getAs<FunctionType>()->getReturnType()->isScalarType())
8538 Diag(NewFD->getLocation(), diag::err_config_scalar_return);
8540 Context.setcudaConfigureCallDecl(NewFD);
8543 // Variadic functions, other than a *declaration* of printf, are not allowed
8544 // in device-side CUDA code, unless someone passed
8545 // -fcuda-allow-variadic-functions.
8546 if (!getLangOpts().CUDAAllowVariadicFunctions && NewFD->isVariadic() &&
8547 (NewFD->hasAttr<CUDADeviceAttr>() ||
8548 NewFD->hasAttr<CUDAGlobalAttr>()) &&
8549 !(II && II->isStr("printf") && NewFD->isExternC() &&
8550 !D.isFunctionDefinition())) {
8551 Diag(NewFD->getLocation(), diag::err_variadic_device_fn);
8555 if (getLangOpts().CPlusPlus) {
8556 if (FunctionTemplate) {
8557 if (NewFD->isInvalidDecl())
8558 FunctionTemplate->setInvalidDecl();
8559 return FunctionTemplate;
8563 if (NewFD->hasAttr<OpenCLKernelAttr>()) {
8564 // OpenCL v1.2 s6.8 static is invalid for kernel functions.
8565 if ((getLangOpts().OpenCLVersion >= 120)
8566 && (SC == SC_Static)) {
8567 Diag(D.getIdentifierLoc(), diag::err_static_kernel);
8571 // OpenCL v1.2, s6.9 -- Kernels can only have return type void.
8572 if (!NewFD->getReturnType()->isVoidType()) {
8573 SourceRange RTRange = NewFD->getReturnTypeSourceRange();
8574 Diag(D.getIdentifierLoc(), diag::err_expected_kernel_void_return_type)
8575 << (RTRange.isValid() ? FixItHint::CreateReplacement(RTRange, "void")
8580 llvm::SmallPtrSet<const Type *, 16> ValidTypes;
8581 for (auto Param : NewFD->parameters())
8582 checkIsValidOpenCLKernelParameter(*this, D, Param, ValidTypes);
8584 for (const ParmVarDecl *Param : NewFD->parameters()) {
8585 QualType PT = Param->getType();
8587 // OpenCL 2.0 pipe restrictions forbids pipe packet types to be non-value
8589 if (getLangOpts().OpenCLVersion >= 200) {
8590 if(const PipeType *PipeTy = PT->getAs<PipeType>()) {
8591 QualType ElemTy = PipeTy->getElementType();
8592 if (ElemTy->isReferenceType() || ElemTy->isPointerType()) {
8593 Diag(Param->getTypeSpecStartLoc(), diag::err_reference_pipe_type );
8600 MarkUnusedFileScopedDecl(NewFD);
8602 // Here we have an function template explicit specialization at class scope.
8603 // The actually specialization will be postponed to template instatiation
8604 // time via the ClassScopeFunctionSpecializationDecl node.
8605 if (isDependentClassScopeExplicitSpecialization) {
8606 ClassScopeFunctionSpecializationDecl *NewSpec =
8607 ClassScopeFunctionSpecializationDecl::Create(
8608 Context, CurContext, SourceLocation(),
8609 cast<CXXMethodDecl>(NewFD),
8610 HasExplicitTemplateArgs, TemplateArgs);
8611 CurContext->addDecl(NewSpec);
8618 /// \brief Perform semantic checking of a new function declaration.
8620 /// Performs semantic analysis of the new function declaration
8621 /// NewFD. This routine performs all semantic checking that does not
8622 /// require the actual declarator involved in the declaration, and is
8623 /// used both for the declaration of functions as they are parsed
8624 /// (called via ActOnDeclarator) and for the declaration of functions
8625 /// that have been instantiated via C++ template instantiation (called
8626 /// via InstantiateDecl).
8628 /// \param IsExplicitSpecialization whether this new function declaration is
8629 /// an explicit specialization of the previous declaration.
8631 /// This sets NewFD->isInvalidDecl() to true if there was an error.
8633 /// \returns true if the function declaration is a redeclaration.
8634 bool Sema::CheckFunctionDeclaration(Scope *S, FunctionDecl *NewFD,
8635 LookupResult &Previous,
8636 bool IsExplicitSpecialization) {
8637 assert(!NewFD->getReturnType()->isVariablyModifiedType() &&
8638 "Variably modified return types are not handled here");
8640 // Determine whether the type of this function should be merged with
8641 // a previous visible declaration. This never happens for functions in C++,
8642 // and always happens in C if the previous declaration was visible.
8643 bool MergeTypeWithPrevious = !getLangOpts().CPlusPlus &&
8644 !Previous.isShadowed();
8646 bool Redeclaration = false;
8647 NamedDecl *OldDecl = nullptr;
8649 // Merge or overload the declaration with an existing declaration of
8650 // the same name, if appropriate.
8651 if (!Previous.empty()) {
8652 // Determine whether NewFD is an overload of PrevDecl or
8653 // a declaration that requires merging. If it's an overload,
8654 // there's no more work to do here; we'll just add the new
8655 // function to the scope.
8656 if (!AllowOverloadingOfFunction(Previous, Context)) {
8657 NamedDecl *Candidate = Previous.getRepresentativeDecl();
8658 if (shouldLinkPossiblyHiddenDecl(Candidate, NewFD)) {
8659 Redeclaration = true;
8660 OldDecl = Candidate;
8663 switch (CheckOverload(S, NewFD, Previous, OldDecl,
8664 /*NewIsUsingDecl*/ false)) {
8666 Redeclaration = true;
8669 case Ovl_NonFunction:
8670 Redeclaration = true;
8674 Redeclaration = false;
8678 if (!getLangOpts().CPlusPlus && !NewFD->hasAttr<OverloadableAttr>()) {
8679 // If a function name is overloadable in C, then every function
8680 // with that name must be marked "overloadable".
8681 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing)
8682 << Redeclaration << NewFD;
8683 NamedDecl *OverloadedDecl = nullptr;
8685 OverloadedDecl = OldDecl;
8686 else if (!Previous.empty())
8687 OverloadedDecl = Previous.getRepresentativeDecl();
8689 Diag(OverloadedDecl->getLocation(),
8690 diag::note_attribute_overloadable_prev_overload);
8691 NewFD->addAttr(OverloadableAttr::CreateImplicit(Context));
8696 // Check for a previous extern "C" declaration with this name.
8697 if (!Redeclaration &&
8698 checkForConflictWithNonVisibleExternC(*this, NewFD, Previous)) {
8699 if (!Previous.empty()) {
8700 // This is an extern "C" declaration with the same name as a previous
8701 // declaration, and thus redeclares that entity...
8702 Redeclaration = true;
8703 OldDecl = Previous.getFoundDecl();
8704 MergeTypeWithPrevious = false;
8706 // ... except in the presence of __attribute__((overloadable)).
8707 if (OldDecl->hasAttr<OverloadableAttr>()) {
8708 if (!getLangOpts().CPlusPlus && !NewFD->hasAttr<OverloadableAttr>()) {
8709 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing)
8710 << Redeclaration << NewFD;
8711 Diag(Previous.getFoundDecl()->getLocation(),
8712 diag::note_attribute_overloadable_prev_overload);
8713 NewFD->addAttr(OverloadableAttr::CreateImplicit(Context));
8715 if (IsOverload(NewFD, cast<FunctionDecl>(OldDecl), false)) {
8716 Redeclaration = false;
8723 // C++11 [dcl.constexpr]p8:
8724 // A constexpr specifier for a non-static member function that is not
8725 // a constructor declares that member function to be const.
8727 // This needs to be delayed until we know whether this is an out-of-line
8728 // definition of a static member function.
8730 // This rule is not present in C++1y, so we produce a backwards
8731 // compatibility warning whenever it happens in C++11.
8732 CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(NewFD);
8733 if (!getLangOpts().CPlusPlus14 && MD && MD->isConstexpr() &&
8734 !MD->isStatic() && !isa<CXXConstructorDecl>(MD) &&
8735 (MD->getTypeQualifiers() & Qualifiers::Const) == 0) {
8736 CXXMethodDecl *OldMD = nullptr;
8738 OldMD = dyn_cast_or_null<CXXMethodDecl>(OldDecl->getAsFunction());
8739 if (!OldMD || !OldMD->isStatic()) {
8740 const FunctionProtoType *FPT =
8741 MD->getType()->castAs<FunctionProtoType>();
8742 FunctionProtoType::ExtProtoInfo EPI = FPT->getExtProtoInfo();
8743 EPI.TypeQuals |= Qualifiers::Const;
8744 MD->setType(Context.getFunctionType(FPT->getReturnType(),
8745 FPT->getParamTypes(), EPI));
8747 // Warn that we did this, if we're not performing template instantiation.
8748 // In that case, we'll have warned already when the template was defined.
8749 if (ActiveTemplateInstantiations.empty()) {
8750 SourceLocation AddConstLoc;
8751 if (FunctionTypeLoc FTL = MD->getTypeSourceInfo()->getTypeLoc()
8752 .IgnoreParens().getAs<FunctionTypeLoc>())
8753 AddConstLoc = getLocForEndOfToken(FTL.getRParenLoc());
8755 Diag(MD->getLocation(), diag::warn_cxx14_compat_constexpr_not_const)
8756 << FixItHint::CreateInsertion(AddConstLoc, " const");
8761 if (Redeclaration) {
8762 // NewFD and OldDecl represent declarations that need to be
8764 if (MergeFunctionDecl(NewFD, OldDecl, S, MergeTypeWithPrevious)) {
8765 NewFD->setInvalidDecl();
8766 return Redeclaration;
8770 Previous.addDecl(OldDecl);
8772 if (FunctionTemplateDecl *OldTemplateDecl
8773 = dyn_cast<FunctionTemplateDecl>(OldDecl)) {
8774 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl());
8775 FunctionTemplateDecl *NewTemplateDecl
8776 = NewFD->getDescribedFunctionTemplate();
8777 assert(NewTemplateDecl && "Template/non-template mismatch");
8778 if (CXXMethodDecl *Method
8779 = dyn_cast<CXXMethodDecl>(NewTemplateDecl->getTemplatedDecl())) {
8780 Method->setAccess(OldTemplateDecl->getAccess());
8781 NewTemplateDecl->setAccess(OldTemplateDecl->getAccess());
8784 // If this is an explicit specialization of a member that is a function
8785 // template, mark it as a member specialization.
8786 if (IsExplicitSpecialization &&
8787 NewTemplateDecl->getInstantiatedFromMemberTemplate()) {
8788 NewTemplateDecl->setMemberSpecialization();
8789 assert(OldTemplateDecl->isMemberSpecialization());
8790 // Explicit specializations of a member template do not inherit deleted
8791 // status from the parent member template that they are specializing.
8792 if (OldTemplateDecl->getTemplatedDecl()->isDeleted()) {
8793 FunctionDecl *const OldTemplatedDecl =
8794 OldTemplateDecl->getTemplatedDecl();
8795 assert(OldTemplatedDecl->getCanonicalDecl() == OldTemplatedDecl);
8796 OldTemplatedDecl->setDeletedAsWritten(false);
8801 // This needs to happen first so that 'inline' propagates.
8802 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl));
8804 if (isa<CXXMethodDecl>(NewFD))
8805 NewFD->setAccess(OldDecl->getAccess());
8809 // Semantic checking for this function declaration (in isolation).
8811 if (getLangOpts().CPlusPlus) {
8812 // C++-specific checks.
8813 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) {
8814 CheckConstructor(Constructor);
8815 } else if (CXXDestructorDecl *Destructor =
8816 dyn_cast<CXXDestructorDecl>(NewFD)) {
8817 CXXRecordDecl *Record = Destructor->getParent();
8818 QualType ClassType = Context.getTypeDeclType(Record);
8820 // FIXME: Shouldn't we be able to perform this check even when the class
8821 // type is dependent? Both gcc and edg can handle that.
8822 if (!ClassType->isDependentType()) {
8823 DeclarationName Name
8824 = Context.DeclarationNames.getCXXDestructorName(
8825 Context.getCanonicalType(ClassType));
8826 if (NewFD->getDeclName() != Name) {
8827 Diag(NewFD->getLocation(), diag::err_destructor_name);
8828 NewFD->setInvalidDecl();
8829 return Redeclaration;
8832 } else if (CXXConversionDecl *Conversion
8833 = dyn_cast<CXXConversionDecl>(NewFD)) {
8834 ActOnConversionDeclarator(Conversion);
8837 // Find any virtual functions that this function overrides.
8838 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(NewFD)) {
8839 if (!Method->isFunctionTemplateSpecialization() &&
8840 !Method->getDescribedFunctionTemplate() &&
8841 Method->isCanonicalDecl()) {
8842 if (AddOverriddenMethods(Method->getParent(), Method)) {
8843 // If the function was marked as "static", we have a problem.
8844 if (NewFD->getStorageClass() == SC_Static) {
8845 ReportOverrides(*this, diag::err_static_overrides_virtual, Method);
8850 if (Method->isStatic())
8851 checkThisInStaticMemberFunctionType(Method);
8854 // Extra checking for C++ overloaded operators (C++ [over.oper]).
8855 if (NewFD->isOverloadedOperator() &&
8856 CheckOverloadedOperatorDeclaration(NewFD)) {
8857 NewFD->setInvalidDecl();
8858 return Redeclaration;
8861 // Extra checking for C++0x literal operators (C++0x [over.literal]).
8862 if (NewFD->getLiteralIdentifier() &&
8863 CheckLiteralOperatorDeclaration(NewFD)) {
8864 NewFD->setInvalidDecl();
8865 return Redeclaration;
8868 // In C++, check default arguments now that we have merged decls. Unless
8869 // the lexical context is the class, because in this case this is done
8870 // during delayed parsing anyway.
8871 if (!CurContext->isRecord())
8872 CheckCXXDefaultArguments(NewFD);
8874 // If this function declares a builtin function, check the type of this
8875 // declaration against the expected type for the builtin.
8876 if (unsigned BuiltinID = NewFD->getBuiltinID()) {
8877 ASTContext::GetBuiltinTypeError Error;
8878 LookupPredefedObjCSuperType(*this, S, NewFD->getIdentifier());
8879 QualType T = Context.GetBuiltinType(BuiltinID, Error);
8880 if (!T.isNull() && !Context.hasSameType(T, NewFD->getType())) {
8881 // The type of this function differs from the type of the builtin,
8882 // so forget about the builtin entirely.
8883 Context.BuiltinInfo.forgetBuiltin(BuiltinID, Context.Idents);
8887 // If this function is declared as being extern "C", then check to see if
8888 // the function returns a UDT (class, struct, or union type) that is not C
8889 // compatible, and if it does, warn the user.
8890 // But, issue any diagnostic on the first declaration only.
8891 if (Previous.empty() && NewFD->isExternC()) {
8892 QualType R = NewFD->getReturnType();
8893 if (R->isIncompleteType() && !R->isVoidType())
8894 Diag(NewFD->getLocation(), diag::warn_return_value_udt_incomplete)
8896 else if (!R.isPODType(Context) && !R->isVoidType() &&
8897 !R->isObjCObjectPointerType())
8898 Diag(NewFD->getLocation(), diag::warn_return_value_udt) << NewFD << R;
8901 return Redeclaration;
8904 void Sema::CheckMain(FunctionDecl* FD, const DeclSpec& DS) {
8905 // C++11 [basic.start.main]p3:
8906 // A program that [...] declares main to be inline, static or
8907 // constexpr is ill-formed.
8908 // C11 6.7.4p4: In a hosted environment, no function specifier(s) shall
8909 // appear in a declaration of main.
8910 // static main is not an error under C99, but we should warn about it.
8911 // We accept _Noreturn main as an extension.
8912 if (FD->getStorageClass() == SC_Static)
8913 Diag(DS.getStorageClassSpecLoc(), getLangOpts().CPlusPlus
8914 ? diag::err_static_main : diag::warn_static_main)
8915 << FixItHint::CreateRemoval(DS.getStorageClassSpecLoc());
8916 if (FD->isInlineSpecified())
8917 Diag(DS.getInlineSpecLoc(), diag::err_inline_main)
8918 << FixItHint::CreateRemoval(DS.getInlineSpecLoc());
8919 if (DS.isNoreturnSpecified()) {
8920 SourceLocation NoreturnLoc = DS.getNoreturnSpecLoc();
8921 SourceRange NoreturnRange(NoreturnLoc, getLocForEndOfToken(NoreturnLoc));
8922 Diag(NoreturnLoc, diag::ext_noreturn_main);
8923 Diag(NoreturnLoc, diag::note_main_remove_noreturn)
8924 << FixItHint::CreateRemoval(NoreturnRange);
8926 if (FD->isConstexpr()) {
8927 Diag(DS.getConstexprSpecLoc(), diag::err_constexpr_main)
8928 << FixItHint::CreateRemoval(DS.getConstexprSpecLoc());
8929 FD->setConstexpr(false);
8932 if (getLangOpts().OpenCL) {
8933 Diag(FD->getLocation(), diag::err_opencl_no_main)
8934 << FD->hasAttr<OpenCLKernelAttr>();
8935 FD->setInvalidDecl();
8939 QualType T = FD->getType();
8940 assert(T->isFunctionType() && "function decl is not of function type");
8941 const FunctionType* FT = T->castAs<FunctionType>();
8943 if (getLangOpts().GNUMode && !getLangOpts().CPlusPlus) {
8944 // In C with GNU extensions we allow main() to have non-integer return
8945 // type, but we should warn about the extension, and we disable the
8946 // implicit-return-zero rule.
8948 // GCC in C mode accepts qualified 'int'.
8949 if (Context.hasSameUnqualifiedType(FT->getReturnType(), Context.IntTy))
8950 FD->setHasImplicitReturnZero(true);
8952 Diag(FD->getTypeSpecStartLoc(), diag::ext_main_returns_nonint);
8953 SourceRange RTRange = FD->getReturnTypeSourceRange();
8954 if (RTRange.isValid())
8955 Diag(RTRange.getBegin(), diag::note_main_change_return_type)
8956 << FixItHint::CreateReplacement(RTRange, "int");
8959 // In C and C++, main magically returns 0 if you fall off the end;
8960 // set the flag which tells us that.
8961 // This is C++ [basic.start.main]p5 and C99 5.1.2.2.3.
8963 // All the standards say that main() should return 'int'.
8964 if (Context.hasSameType(FT->getReturnType(), Context.IntTy))
8965 FD->setHasImplicitReturnZero(true);
8967 // Otherwise, this is just a flat-out error.
8968 SourceRange RTRange = FD->getReturnTypeSourceRange();
8969 Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint)
8970 << (RTRange.isValid() ? FixItHint::CreateReplacement(RTRange, "int")
8972 FD->setInvalidDecl(true);
8976 // Treat protoless main() as nullary.
8977 if (isa<FunctionNoProtoType>(FT)) return;
8979 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT);
8980 unsigned nparams = FTP->getNumParams();
8981 assert(FD->getNumParams() == nparams);
8983 bool HasExtraParameters = (nparams > 3);
8985 if (FTP->isVariadic()) {
8986 Diag(FD->getLocation(), diag::ext_variadic_main);
8987 // FIXME: if we had information about the location of the ellipsis, we
8988 // could add a FixIt hint to remove it as a parameter.
8991 // Darwin passes an undocumented fourth argument of type char**. If
8992 // other platforms start sprouting these, the logic below will start
8994 if (nparams == 4 && Context.getTargetInfo().getTriple().isOSDarwin())
8995 HasExtraParameters = false;
8997 if (HasExtraParameters) {
8998 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams;
8999 FD->setInvalidDecl(true);
9003 // FIXME: a lot of the following diagnostics would be improved
9004 // if we had some location information about types.
9007 Context.getPointerType(Context.getPointerType(Context.CharTy));
9008 QualType Expected[] = { Context.IntTy, CharPP, CharPP, CharPP };
9010 for (unsigned i = 0; i < nparams; ++i) {
9011 QualType AT = FTP->getParamType(i);
9013 bool mismatch = true;
9015 if (Context.hasSameUnqualifiedType(AT, Expected[i]))
9017 else if (Expected[i] == CharPP) {
9018 // As an extension, the following forms are okay:
9020 // char const * const *
9023 QualifierCollector qs;
9024 const PointerType* PT;
9025 if ((PT = qs.strip(AT)->getAs<PointerType>()) &&
9026 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) &&
9027 Context.hasSameType(QualType(qs.strip(PT->getPointeeType()), 0),
9030 mismatch = !qs.empty();
9035 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i];
9036 // TODO: suggest replacing given type with expected type
9037 FD->setInvalidDecl(true);
9041 if (nparams == 1 && !FD->isInvalidDecl()) {
9042 Diag(FD->getLocation(), diag::warn_main_one_arg);
9045 if (!FD->isInvalidDecl() && FD->getDescribedFunctionTemplate()) {
9046 Diag(FD->getLocation(), diag::err_mainlike_template_decl) << FD;
9047 FD->setInvalidDecl();
9051 void Sema::CheckMSVCRTEntryPoint(FunctionDecl *FD) {
9052 QualType T = FD->getType();
9053 assert(T->isFunctionType() && "function decl is not of function type");
9054 const FunctionType *FT = T->castAs<FunctionType>();
9056 // Set an implicit return of 'zero' if the function can return some integral,
9057 // enumeration, pointer or nullptr type.
9058 if (FT->getReturnType()->isIntegralOrEnumerationType() ||
9059 FT->getReturnType()->isAnyPointerType() ||
9060 FT->getReturnType()->isNullPtrType())
9061 // DllMain is exempt because a return value of zero means it failed.
9062 if (FD->getName() != "DllMain")
9063 FD->setHasImplicitReturnZero(true);
9065 if (!FD->isInvalidDecl() && FD->getDescribedFunctionTemplate()) {
9066 Diag(FD->getLocation(), diag::err_mainlike_template_decl) << FD;
9067 FD->setInvalidDecl();
9071 bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) {
9072 // FIXME: Need strict checking. In C89, we need to check for
9073 // any assignment, increment, decrement, function-calls, or
9074 // commas outside of a sizeof. In C99, it's the same list,
9075 // except that the aforementioned are allowed in unevaluated
9076 // expressions. Everything else falls under the
9077 // "may accept other forms of constant expressions" exception.
9078 // (We never end up here for C++, so the constant expression
9079 // rules there don't matter.)
9080 const Expr *Culprit;
9081 if (Init->isConstantInitializer(Context, false, &Culprit))
9083 Diag(Culprit->getExprLoc(), diag::err_init_element_not_constant)
9084 << Culprit->getSourceRange();
9089 // Visits an initialization expression to see if OrigDecl is evaluated in
9090 // its own initialization and throws a warning if it does.
9091 class SelfReferenceChecker
9092 : public EvaluatedExprVisitor<SelfReferenceChecker> {
9097 bool isReferenceType;
9100 llvm::SmallVector<unsigned, 4> InitFieldIndex;
9103 typedef EvaluatedExprVisitor<SelfReferenceChecker> Inherited;
9105 SelfReferenceChecker(Sema &S, Decl *OrigDecl) : Inherited(S.Context),
9106 S(S), OrigDecl(OrigDecl) {
9108 isRecordType = false;
9109 isReferenceType = false;
9111 if (ValueDecl *VD = dyn_cast<ValueDecl>(OrigDecl)) {
9112 isPODType = VD->getType().isPODType(S.Context);
9113 isRecordType = VD->getType()->isRecordType();
9114 isReferenceType = VD->getType()->isReferenceType();
9118 // For most expressions, just call the visitor. For initializer lists,
9119 // track the index of the field being initialized since fields are
9120 // initialized in order allowing use of previously initialized fields.
9121 void CheckExpr(Expr *E) {
9122 InitListExpr *InitList = dyn_cast<InitListExpr>(E);
9128 // Track and increment the index here.
9130 InitFieldIndex.push_back(0);
9131 for (auto Child : InitList->children()) {
9132 CheckExpr(cast<Expr>(Child));
9133 ++InitFieldIndex.back();
9135 InitFieldIndex.pop_back();
9138 // Returns true if MemberExpr is checked and no futher checking is needed.
9139 // Returns false if additional checking is required.
9140 bool CheckInitListMemberExpr(MemberExpr *E, bool CheckReference) {
9141 llvm::SmallVector<FieldDecl*, 4> Fields;
9143 bool ReferenceField = false;
9145 // Get the field memebers used.
9146 while (MemberExpr *ME = dyn_cast<MemberExpr>(Base)) {
9147 FieldDecl *FD = dyn_cast<FieldDecl>(ME->getMemberDecl());
9150 Fields.push_back(FD);
9151 if (FD->getType()->isReferenceType())
9152 ReferenceField = true;
9153 Base = ME->getBase()->IgnoreParenImpCasts();
9156 // Keep checking only if the base Decl is the same.
9157 DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Base);
9158 if (!DRE || DRE->getDecl() != OrigDecl)
9161 // A reference field can be bound to an unininitialized field.
9162 if (CheckReference && !ReferenceField)
9165 // Convert FieldDecls to their index number.
9166 llvm::SmallVector<unsigned, 4> UsedFieldIndex;
9167 for (const FieldDecl *I : llvm::reverse(Fields))
9168 UsedFieldIndex.push_back(I->getFieldIndex());
9170 // See if a warning is needed by checking the first difference in index
9171 // numbers. If field being used has index less than the field being
9172 // initialized, then the use is safe.
9173 for (auto UsedIter = UsedFieldIndex.begin(),
9174 UsedEnd = UsedFieldIndex.end(),
9175 OrigIter = InitFieldIndex.begin(),
9176 OrigEnd = InitFieldIndex.end();
9177 UsedIter != UsedEnd && OrigIter != OrigEnd; ++UsedIter, ++OrigIter) {
9178 if (*UsedIter < *OrigIter)
9180 if (*UsedIter > *OrigIter)
9184 // TODO: Add a different warning which will print the field names.
9185 HandleDeclRefExpr(DRE);
9189 // For most expressions, the cast is directly above the DeclRefExpr.
9190 // For conditional operators, the cast can be outside the conditional
9191 // operator if both expressions are DeclRefExpr's.
9192 void HandleValue(Expr *E) {
9193 E = E->IgnoreParens();
9194 if (DeclRefExpr* DRE = dyn_cast<DeclRefExpr>(E)) {
9195 HandleDeclRefExpr(DRE);
9199 if (ConditionalOperator *CO = dyn_cast<ConditionalOperator>(E)) {
9200 Visit(CO->getCond());
9201 HandleValue(CO->getTrueExpr());
9202 HandleValue(CO->getFalseExpr());
9206 if (BinaryConditionalOperator *BCO =
9207 dyn_cast<BinaryConditionalOperator>(E)) {
9208 Visit(BCO->getCond());
9209 HandleValue(BCO->getFalseExpr());
9213 if (OpaqueValueExpr *OVE = dyn_cast<OpaqueValueExpr>(E)) {
9214 HandleValue(OVE->getSourceExpr());
9218 if (BinaryOperator *BO = dyn_cast<BinaryOperator>(E)) {
9219 if (BO->getOpcode() == BO_Comma) {
9220 Visit(BO->getLHS());
9221 HandleValue(BO->getRHS());
9226 if (isa<MemberExpr>(E)) {
9228 if (CheckInitListMemberExpr(cast<MemberExpr>(E),
9229 false /*CheckReference*/))
9233 Expr *Base = E->IgnoreParenImpCasts();
9234 while (MemberExpr *ME = dyn_cast<MemberExpr>(Base)) {
9235 // Check for static member variables and don't warn on them.
9236 if (!isa<FieldDecl>(ME->getMemberDecl()))
9238 Base = ME->getBase()->IgnoreParenImpCasts();
9240 if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Base))
9241 HandleDeclRefExpr(DRE);
9248 // Reference types not handled in HandleValue are handled here since all
9249 // uses of references are bad, not just r-value uses.
9250 void VisitDeclRefExpr(DeclRefExpr *E) {
9251 if (isReferenceType)
9252 HandleDeclRefExpr(E);
9255 void VisitImplicitCastExpr(ImplicitCastExpr *E) {
9256 if (E->getCastKind() == CK_LValueToRValue) {
9257 HandleValue(E->getSubExpr());
9261 Inherited::VisitImplicitCastExpr(E);
9264 void VisitMemberExpr(MemberExpr *E) {
9266 if (CheckInitListMemberExpr(E, true /*CheckReference*/))
9270 // Don't warn on arrays since they can be treated as pointers.
9271 if (E->getType()->canDecayToPointerType()) return;
9273 // Warn when a non-static method call is followed by non-static member
9274 // field accesses, which is followed by a DeclRefExpr.
9275 CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(E->getMemberDecl());
9276 bool Warn = (MD && !MD->isStatic());
9277 Expr *Base = E->getBase()->IgnoreParenImpCasts();
9278 while (MemberExpr *ME = dyn_cast<MemberExpr>(Base)) {
9279 if (!isa<FieldDecl>(ME->getMemberDecl()))
9281 Base = ME->getBase()->IgnoreParenImpCasts();
9284 if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Base)) {
9286 HandleDeclRefExpr(DRE);
9290 // The base of a MemberExpr is not a MemberExpr or a DeclRefExpr.
9291 // Visit that expression.
9295 void VisitCXXOperatorCallExpr(CXXOperatorCallExpr *E) {
9296 Expr *Callee = E->getCallee();
9298 if (isa<UnresolvedLookupExpr>(Callee))
9299 return Inherited::VisitCXXOperatorCallExpr(E);
9302 for (auto Arg: E->arguments())
9303 HandleValue(Arg->IgnoreParenImpCasts());
9306 void VisitUnaryOperator(UnaryOperator *E) {
9307 // For POD record types, addresses of its own members are well-defined.
9308 if (E->getOpcode() == UO_AddrOf && isRecordType &&
9309 isa<MemberExpr>(E->getSubExpr()->IgnoreParens())) {
9311 HandleValue(E->getSubExpr());
9315 if (E->isIncrementDecrementOp()) {
9316 HandleValue(E->getSubExpr());
9320 Inherited::VisitUnaryOperator(E);
9323 void VisitObjCMessageExpr(ObjCMessageExpr *E) {}
9325 void VisitCXXConstructExpr(CXXConstructExpr *E) {
9326 if (E->getConstructor()->isCopyConstructor()) {
9327 Expr *ArgExpr = E->getArg(0);
9328 if (InitListExpr *ILE = dyn_cast<InitListExpr>(ArgExpr))
9329 if (ILE->getNumInits() == 1)
9330 ArgExpr = ILE->getInit(0);
9331 if (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(ArgExpr))
9332 if (ICE->getCastKind() == CK_NoOp)
9333 ArgExpr = ICE->getSubExpr();
9334 HandleValue(ArgExpr);
9337 Inherited::VisitCXXConstructExpr(E);
9340 void VisitCallExpr(CallExpr *E) {
9341 // Treat std::move as a use.
9342 if (E->getNumArgs() == 1) {
9343 if (FunctionDecl *FD = E->getDirectCallee()) {
9344 if (FD->isInStdNamespace() && FD->getIdentifier() &&
9345 FD->getIdentifier()->isStr("move")) {
9346 HandleValue(E->getArg(0));
9352 Inherited::VisitCallExpr(E);
9355 void VisitBinaryOperator(BinaryOperator *E) {
9356 if (E->isCompoundAssignmentOp()) {
9357 HandleValue(E->getLHS());
9362 Inherited::VisitBinaryOperator(E);
9365 // A custom visitor for BinaryConditionalOperator is needed because the
9366 // regular visitor would check the condition and true expression separately
9367 // but both point to the same place giving duplicate diagnostics.
9368 void VisitBinaryConditionalOperator(BinaryConditionalOperator *E) {
9369 Visit(E->getCond());
9370 Visit(E->getFalseExpr());
9373 void HandleDeclRefExpr(DeclRefExpr *DRE) {
9374 Decl* ReferenceDecl = DRE->getDecl();
9375 if (OrigDecl != ReferenceDecl) return;
9377 if (isReferenceType) {
9378 diag = diag::warn_uninit_self_reference_in_reference_init;
9379 } else if (cast<VarDecl>(OrigDecl)->isStaticLocal()) {
9380 diag = diag::warn_static_self_reference_in_init;
9381 } else if (isa<TranslationUnitDecl>(OrigDecl->getDeclContext()) ||
9382 isa<NamespaceDecl>(OrigDecl->getDeclContext()) ||
9383 DRE->getDecl()->getType()->isRecordType()) {
9384 diag = diag::warn_uninit_self_reference_in_init;
9386 // Local variables will be handled by the CFG analysis.
9390 S.DiagRuntimeBehavior(DRE->getLocStart(), DRE,
9392 << DRE->getNameInfo().getName()
9393 << OrigDecl->getLocation()
9394 << DRE->getSourceRange());
9398 /// CheckSelfReference - Warns if OrigDecl is used in expression E.
9399 static void CheckSelfReference(Sema &S, Decl* OrigDecl, Expr *E,
9401 // Parameters arguments are occassionially constructed with itself,
9402 // for instance, in recursive functions. Skip them.
9403 if (isa<ParmVarDecl>(OrigDecl))
9406 E = E->IgnoreParens();
9408 // Skip checking T a = a where T is not a record or reference type.
9409 // Doing so is a way to silence uninitialized warnings.
9410 if (!DirectInit && !cast<VarDecl>(OrigDecl)->getType()->isRecordType())
9411 if (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(E))
9412 if (ICE->getCastKind() == CK_LValueToRValue)
9413 if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(ICE->getSubExpr()))
9414 if (DRE->getDecl() == OrigDecl)
9417 SelfReferenceChecker(S, OrigDecl).CheckExpr(E);
9419 } // end anonymous namespace
9421 QualType Sema::deduceVarTypeFromInitializer(VarDecl *VDecl,
9422 DeclarationName Name, QualType Type,
9423 TypeSourceInfo *TSI,
9424 SourceRange Range, bool DirectInit,
9426 bool IsInitCapture = !VDecl;
9427 assert((!VDecl || !VDecl->isInitCapture()) &&
9428 "init captures are expected to be deduced prior to initialization");
9430 ArrayRef<Expr *> DeduceInits = Init;
9432 if (auto *PL = dyn_cast<ParenListExpr>(Init))
9433 DeduceInits = PL->exprs();
9434 else if (auto *IL = dyn_cast<InitListExpr>(Init))
9435 DeduceInits = IL->inits();
9438 // Deduction only works if we have exactly one source expression.
9439 if (DeduceInits.empty()) {
9440 // It isn't possible to write this directly, but it is possible to
9441 // end up in this situation with "auto x(some_pack...);"
9442 Diag(Init->getLocStart(), IsInitCapture
9443 ? diag::err_init_capture_no_expression
9444 : diag::err_auto_var_init_no_expression)
9445 << Name << Type << Range;
9449 if (DeduceInits.size() > 1) {
9450 Diag(DeduceInits[1]->getLocStart(),
9451 IsInitCapture ? diag::err_init_capture_multiple_expressions
9452 : diag::err_auto_var_init_multiple_expressions)
9453 << Name << Type << Range;
9457 Expr *DeduceInit = DeduceInits[0];
9458 if (DirectInit && isa<InitListExpr>(DeduceInit)) {
9459 Diag(Init->getLocStart(), IsInitCapture
9460 ? diag::err_init_capture_paren_braces
9461 : diag::err_auto_var_init_paren_braces)
9462 << isa<InitListExpr>(Init) << Name << Type << Range;
9466 // Expressions default to 'id' when we're in a debugger.
9467 bool DefaultedAnyToId = false;
9468 if (getLangOpts().DebuggerCastResultToId &&
9469 Init->getType() == Context.UnknownAnyTy && !IsInitCapture) {
9470 ExprResult Result = forceUnknownAnyToType(Init, Context.getObjCIdType());
9471 if (Result.isInvalid()) {
9474 Init = Result.get();
9475 DefaultedAnyToId = true;
9478 QualType DeducedType;
9479 if (DeduceAutoType(TSI, DeduceInit, DeducedType) == DAR_Failed) {
9481 DiagnoseAutoDeductionFailure(VDecl, DeduceInit);
9482 else if (isa<InitListExpr>(Init))
9483 Diag(Range.getBegin(),
9484 diag::err_init_capture_deduction_failure_from_init_list)
9486 << (DeduceInit->getType().isNull() ? TSI->getType()
9487 : DeduceInit->getType())
9488 << DeduceInit->getSourceRange();
9490 Diag(Range.getBegin(), diag::err_init_capture_deduction_failure)
9491 << Name << TSI->getType()
9492 << (DeduceInit->getType().isNull() ? TSI->getType()
9493 : DeduceInit->getType())
9494 << DeduceInit->getSourceRange();
9497 // Warn if we deduced 'id'. 'auto' usually implies type-safety, but using
9498 // 'id' instead of a specific object type prevents most of our usual
9500 // We only want to warn outside of template instantiations, though:
9501 // inside a template, the 'id' could have come from a parameter.
9502 if (ActiveTemplateInstantiations.empty() && !DefaultedAnyToId &&
9503 !IsInitCapture && !DeducedType.isNull() && DeducedType->isObjCIdType()) {
9504 SourceLocation Loc = TSI->getTypeLoc().getBeginLoc();
9505 Diag(Loc, diag::warn_auto_var_is_id) << Name << Range;
9511 /// AddInitializerToDecl - Adds the initializer Init to the
9512 /// declaration dcl. If DirectInit is true, this is C++ direct
9513 /// initialization rather than copy initialization.
9514 void Sema::AddInitializerToDecl(Decl *RealDecl, Expr *Init,
9515 bool DirectInit, bool TypeMayContainAuto) {
9516 // If there is no declaration, there was an error parsing it. Just ignore
9518 if (!RealDecl || RealDecl->isInvalidDecl()) {
9519 CorrectDelayedTyposInExpr(Init, dyn_cast_or_null<VarDecl>(RealDecl));
9523 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) {
9524 // Pure-specifiers are handled in ActOnPureSpecifier.
9525 Diag(Method->getLocation(), diag::err_member_function_initialization)
9526 << Method->getDeclName() << Init->getSourceRange();
9527 Method->setInvalidDecl();
9531 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl);
9533 assert(!isa<FieldDecl>(RealDecl) && "field init shouldn't get here");
9534 Diag(RealDecl->getLocation(), diag::err_illegal_initializer);
9535 RealDecl->setInvalidDecl();
9539 // C++11 [decl.spec.auto]p6. Deduce the type which 'auto' stands in for.
9540 if (TypeMayContainAuto && VDecl->getType()->isUndeducedType()) {
9541 // Attempt typo correction early so that the type of the init expression can
9542 // be deduced based on the chosen correction if the original init contains a
9544 ExprResult Res = CorrectDelayedTyposInExpr(Init, VDecl);
9545 if (!Res.isUsable()) {
9546 RealDecl->setInvalidDecl();
9551 QualType DeducedType = deduceVarTypeFromInitializer(
9552 VDecl, VDecl->getDeclName(), VDecl->getType(),
9553 VDecl->getTypeSourceInfo(), VDecl->getSourceRange(), DirectInit, Init);
9554 if (DeducedType.isNull()) {
9555 RealDecl->setInvalidDecl();
9559 VDecl->setType(DeducedType);
9560 assert(VDecl->isLinkageValid());
9562 // In ARC, infer lifetime.
9563 if (getLangOpts().ObjCAutoRefCount && inferObjCARCLifetime(VDecl))
9564 VDecl->setInvalidDecl();
9566 // If this is a redeclaration, check that the type we just deduced matches
9567 // the previously declared type.
9568 if (VarDecl *Old = VDecl->getPreviousDecl()) {
9569 // We never need to merge the type, because we cannot form an incomplete
9570 // array of auto, nor deduce such a type.
9571 MergeVarDeclTypes(VDecl, Old, /*MergeTypeWithPrevious*/ false);
9574 // Check the deduced type is valid for a variable declaration.
9575 CheckVariableDeclarationType(VDecl);
9576 if (VDecl->isInvalidDecl())
9580 // dllimport cannot be used on variable definitions.
9581 if (VDecl->hasAttr<DLLImportAttr>() && !VDecl->isStaticDataMember()) {
9582 Diag(VDecl->getLocation(), diag::err_attribute_dllimport_data_definition);
9583 VDecl->setInvalidDecl();
9587 if (VDecl->isLocalVarDecl() && VDecl->hasExternalStorage()) {
9588 // C99 6.7.8p5. C++ has no such restriction, but that is a defect.
9589 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init);
9590 VDecl->setInvalidDecl();
9594 if (!VDecl->getType()->isDependentType()) {
9595 // A definition must end up with a complete type, which means it must be
9596 // complete with the restriction that an array type might be completed by
9597 // the initializer; note that later code assumes this restriction.
9598 QualType BaseDeclType = VDecl->getType();
9599 if (const ArrayType *Array = Context.getAsIncompleteArrayType(BaseDeclType))
9600 BaseDeclType = Array->getElementType();
9601 if (RequireCompleteType(VDecl->getLocation(), BaseDeclType,
9602 diag::err_typecheck_decl_incomplete_type)) {
9603 RealDecl->setInvalidDecl();
9607 // The variable can not have an abstract class type.
9608 if (RequireNonAbstractType(VDecl->getLocation(), VDecl->getType(),
9609 diag::err_abstract_type_in_decl,
9610 AbstractVariableType))
9611 VDecl->setInvalidDecl();
9615 if ((Def = VDecl->getDefinition()) && Def != VDecl) {
9616 NamedDecl *Hidden = nullptr;
9617 if (!hasVisibleDefinition(Def, &Hidden) &&
9618 (VDecl->getFormalLinkage() == InternalLinkage ||
9619 VDecl->getDescribedVarTemplate() ||
9620 VDecl->getNumTemplateParameterLists() ||
9621 VDecl->getDeclContext()->isDependentContext())) {
9622 // The previous definition is hidden, and multiple definitions are
9623 // permitted (in separate TUs). Form another definition of it.
9625 Diag(VDecl->getLocation(), diag::err_redefinition)
9626 << VDecl->getDeclName();
9627 Diag(Def->getLocation(), diag::note_previous_definition);
9628 VDecl->setInvalidDecl();
9633 if (getLangOpts().CPlusPlus) {
9634 // C++ [class.static.data]p4
9635 // If a static data member is of const integral or const
9636 // enumeration type, its declaration in the class definition can
9637 // specify a constant-initializer which shall be an integral
9638 // constant expression (5.19). In that case, the member can appear
9639 // in integral constant expressions. The member shall still be
9640 // defined in a namespace scope if it is used in the program and the
9641 // namespace scope definition shall not contain an initializer.
9643 // We already performed a redefinition check above, but for static
9644 // data members we also need to check whether there was an in-class
9645 // declaration with an initializer.
9646 if (VDecl->isStaticDataMember() && VDecl->getCanonicalDecl()->hasInit()) {
9647 Diag(Init->getExprLoc(), diag::err_static_data_member_reinitialization)
9648 << VDecl->getDeclName();
9649 Diag(VDecl->getCanonicalDecl()->getInit()->getExprLoc(),
9650 diag::note_previous_initializer)
9655 if (VDecl->hasLocalStorage())
9656 getCurFunction()->setHasBranchProtectedScope();
9658 if (DiagnoseUnexpandedParameterPack(Init, UPPC_Initializer)) {
9659 VDecl->setInvalidDecl();
9664 // OpenCL 1.1 6.5.2: "Variables allocated in the __local address space inside
9665 // a kernel function cannot be initialized."
9666 if (VDecl->getType().getAddressSpace() == LangAS::opencl_local) {
9667 Diag(VDecl->getLocation(), diag::err_local_cant_init);
9668 VDecl->setInvalidDecl();
9672 // Get the decls type and save a reference for later, since
9673 // CheckInitializerTypes may change it.
9674 QualType DclT = VDecl->getType(), SavT = DclT;
9676 // Expressions default to 'id' when we're in a debugger
9677 // and we are assigning it to a variable of Objective-C pointer type.
9678 if (getLangOpts().DebuggerCastResultToId && DclT->isObjCObjectPointerType() &&
9679 Init->getType() == Context.UnknownAnyTy) {
9680 ExprResult Result = forceUnknownAnyToType(Init, Context.getObjCIdType());
9681 if (Result.isInvalid()) {
9682 VDecl->setInvalidDecl();
9685 Init = Result.get();
9688 // Perform the initialization.
9689 ParenListExpr *CXXDirectInit = dyn_cast<ParenListExpr>(Init);
9690 if (!VDecl->isInvalidDecl()) {
9691 InitializedEntity Entity = InitializedEntity::InitializeVariable(VDecl);
9692 InitializationKind Kind =
9695 ? InitializationKind::CreateDirect(VDecl->getLocation(),
9696 Init->getLocStart(),
9698 : InitializationKind::CreateDirectList(VDecl->getLocation())
9699 : InitializationKind::CreateCopy(VDecl->getLocation(),
9700 Init->getLocStart());
9702 MultiExprArg Args = Init;
9704 Args = MultiExprArg(CXXDirectInit->getExprs(),
9705 CXXDirectInit->getNumExprs());
9707 // Try to correct any TypoExprs in the initialization arguments.
9708 for (size_t Idx = 0; Idx < Args.size(); ++Idx) {
9709 ExprResult Res = CorrectDelayedTyposInExpr(
9710 Args[Idx], VDecl, [this, Entity, Kind](Expr *E) {
9711 InitializationSequence Init(*this, Entity, Kind, MultiExprArg(E));
9712 return Init.Failed() ? ExprError() : E;
9714 if (Res.isInvalid()) {
9715 VDecl->setInvalidDecl();
9716 } else if (Res.get() != Args[Idx]) {
9717 Args[Idx] = Res.get();
9720 if (VDecl->isInvalidDecl())
9723 InitializationSequence InitSeq(*this, Entity, Kind, Args,
9724 /*TopLevelOfInitList=*/false,
9725 /*TreatUnavailableAsInvalid=*/false);
9726 ExprResult Result = InitSeq.Perform(*this, Entity, Kind, Args, &DclT);
9727 if (Result.isInvalid()) {
9728 VDecl->setInvalidDecl();
9732 Init = Result.getAs<Expr>();
9735 // Check for self-references within variable initializers.
9736 // Variables declared within a function/method body (except for references)
9737 // are handled by a dataflow analysis.
9738 if (!VDecl->hasLocalStorage() || VDecl->getType()->isRecordType() ||
9739 VDecl->getType()->isReferenceType()) {
9740 CheckSelfReference(*this, RealDecl, Init, DirectInit);
9743 // If the type changed, it means we had an incomplete type that was
9744 // completed by the initializer. For example:
9745 // int ary[] = { 1, 3, 5 };
9746 // "ary" transitions from an IncompleteArrayType to a ConstantArrayType.
9747 if (!VDecl->isInvalidDecl() && (DclT != SavT))
9748 VDecl->setType(DclT);
9750 if (!VDecl->isInvalidDecl()) {
9751 checkUnsafeAssigns(VDecl->getLocation(), VDecl->getType(), Init);
9753 if (VDecl->hasAttr<BlocksAttr>())
9754 checkRetainCycles(VDecl, Init);
9756 // It is safe to assign a weak reference into a strong variable.
9757 // Although this code can still have problems:
9758 // id x = self.weakProp;
9759 // id y = self.weakProp;
9760 // we do not warn to warn spuriously when 'x' and 'y' are on separate
9761 // paths through the function. This should be revisited if
9762 // -Wrepeated-use-of-weak is made flow-sensitive.
9763 if (VDecl->getType().getObjCLifetime() == Qualifiers::OCL_Strong &&
9764 !Diags.isIgnored(diag::warn_arc_repeated_use_of_weak,
9765 Init->getLocStart()))
9766 getCurFunction()->markSafeWeakUse(Init);
9769 // The initialization is usually a full-expression.
9771 // FIXME: If this is a braced initialization of an aggregate, it is not
9772 // an expression, and each individual field initializer is a separate
9773 // full-expression. For instance, in:
9775 // struct Temp { ~Temp(); };
9776 // struct S { S(Temp); };
9777 // struct T { S a, b; } t = { Temp(), Temp() }
9779 // we should destroy the first Temp before constructing the second.
9780 ExprResult Result = ActOnFinishFullExpr(Init, VDecl->getLocation(),
9782 VDecl->isConstexpr());
9783 if (Result.isInvalid()) {
9784 VDecl->setInvalidDecl();
9787 Init = Result.get();
9789 // Attach the initializer to the decl.
9790 VDecl->setInit(Init);
9792 if (VDecl->isLocalVarDecl()) {
9793 // C99 6.7.8p4: All the expressions in an initializer for an object that has
9794 // static storage duration shall be constant expressions or string literals.
9795 // C++ does not have this restriction.
9796 if (!getLangOpts().CPlusPlus && !VDecl->isInvalidDecl()) {
9797 const Expr *Culprit;
9798 if (VDecl->getStorageClass() == SC_Static)
9799 CheckForConstantInitializer(Init, DclT);
9800 // C89 is stricter than C99 for non-static aggregate types.
9801 // C89 6.5.7p3: All the expressions [...] in an initializer list
9802 // for an object that has aggregate or union type shall be
9803 // constant expressions.
9804 else if (!getLangOpts().C99 && VDecl->getType()->isAggregateType() &&
9805 isa<InitListExpr>(Init) &&
9806 !Init->isConstantInitializer(Context, false, &Culprit))
9807 Diag(Culprit->getExprLoc(),
9808 diag::ext_aggregate_init_not_constant)
9809 << Culprit->getSourceRange();
9811 } else if (VDecl->isStaticDataMember() && !VDecl->isInline() &&
9812 VDecl->getLexicalDeclContext()->isRecord()) {
9813 // This is an in-class initialization for a static data member, e.g.,
9816 // static const int value = 17;
9819 // C++ [class.mem]p4:
9820 // A member-declarator can contain a constant-initializer only
9821 // if it declares a static member (9.4) of const integral or
9822 // const enumeration type, see 9.4.2.
9824 // C++11 [class.static.data]p3:
9825 // If a non-volatile non-inline const static data member is of integral
9826 // or enumeration type, its declaration in the class definition can
9827 // specify a brace-or-equal-initializer in which every initalizer-clause
9828 // that is an assignment-expression is a constant expression. A static
9829 // data member of literal type can be declared in the class definition
9830 // with the constexpr specifier; if so, its declaration shall specify a
9831 // brace-or-equal-initializer in which every initializer-clause that is
9832 // an assignment-expression is a constant expression.
9834 // Do nothing on dependent types.
9835 if (DclT->isDependentType()) {
9837 // Allow any 'static constexpr' members, whether or not they are of literal
9838 // type. We separately check that every constexpr variable is of literal
9840 } else if (VDecl->isConstexpr()) {
9842 // Require constness.
9843 } else if (!DclT.isConstQualified()) {
9844 Diag(VDecl->getLocation(), diag::err_in_class_initializer_non_const)
9845 << Init->getSourceRange();
9846 VDecl->setInvalidDecl();
9848 // We allow integer constant expressions in all cases.
9849 } else if (DclT->isIntegralOrEnumerationType()) {
9850 // Check whether the expression is a constant expression.
9852 if (getLangOpts().CPlusPlus11 && DclT.isVolatileQualified())
9853 // In C++11, a non-constexpr const static data member with an
9854 // in-class initializer cannot be volatile.
9855 Diag(VDecl->getLocation(), diag::err_in_class_initializer_volatile);
9856 else if (Init->isValueDependent())
9857 ; // Nothing to check.
9858 else if (Init->isIntegerConstantExpr(Context, &Loc))
9859 ; // Ok, it's an ICE!
9860 else if (Init->isEvaluatable(Context)) {
9861 // If we can constant fold the initializer through heroics, accept it,
9862 // but report this as a use of an extension for -pedantic.
9863 Diag(Loc, diag::ext_in_class_initializer_non_constant)
9864 << Init->getSourceRange();
9866 // Otherwise, this is some crazy unknown case. Report the issue at the
9867 // location provided by the isIntegerConstantExpr failed check.
9868 Diag(Loc, diag::err_in_class_initializer_non_constant)
9869 << Init->getSourceRange();
9870 VDecl->setInvalidDecl();
9873 // We allow foldable floating-point constants as an extension.
9874 } else if (DclT->isFloatingType()) { // also permits complex, which is ok
9875 // In C++98, this is a GNU extension. In C++11, it is not, but we support
9876 // it anyway and provide a fixit to add the 'constexpr'.
9877 if (getLangOpts().CPlusPlus11) {
9878 Diag(VDecl->getLocation(),
9879 diag::ext_in_class_initializer_float_type_cxx11)
9880 << DclT << Init->getSourceRange();
9881 Diag(VDecl->getLocStart(),
9882 diag::note_in_class_initializer_float_type_cxx11)
9883 << FixItHint::CreateInsertion(VDecl->getLocStart(), "constexpr ");
9885 Diag(VDecl->getLocation(), diag::ext_in_class_initializer_float_type)
9886 << DclT << Init->getSourceRange();
9888 if (!Init->isValueDependent() && !Init->isEvaluatable(Context)) {
9889 Diag(Init->getExprLoc(), diag::err_in_class_initializer_non_constant)
9890 << Init->getSourceRange();
9891 VDecl->setInvalidDecl();
9895 // Suggest adding 'constexpr' in C++11 for literal types.
9896 } else if (getLangOpts().CPlusPlus11 && DclT->isLiteralType(Context)) {
9897 Diag(VDecl->getLocation(), diag::err_in_class_initializer_literal_type)
9898 << DclT << Init->getSourceRange()
9899 << FixItHint::CreateInsertion(VDecl->getLocStart(), "constexpr ");
9900 VDecl->setConstexpr(true);
9903 Diag(VDecl->getLocation(), diag::err_in_class_initializer_bad_type)
9904 << DclT << Init->getSourceRange();
9905 VDecl->setInvalidDecl();
9907 } else if (VDecl->isFileVarDecl()) {
9908 if (VDecl->getStorageClass() == SC_Extern &&
9909 (!getLangOpts().CPlusPlus ||
9910 !(Context.getBaseElementType(VDecl->getType()).isConstQualified() ||
9911 VDecl->isExternC())) &&
9912 !isTemplateInstantiation(VDecl->getTemplateSpecializationKind()))
9913 Diag(VDecl->getLocation(), diag::warn_extern_init);
9915 // C99 6.7.8p4. All file scoped initializers need to be constant.
9916 if (!getLangOpts().CPlusPlus && !VDecl->isInvalidDecl())
9917 CheckForConstantInitializer(Init, DclT);
9920 // We will represent direct-initialization similarly to copy-initialization:
9921 // int x(1); -as-> int x = 1;
9922 // ClassType x(a,b,c); -as-> ClassType x = ClassType(a,b,c);
9924 // Clients that want to distinguish between the two forms, can check for
9925 // direct initializer using VarDecl::getInitStyle().
9926 // A major benefit is that clients that don't particularly care about which
9927 // exactly form was it (like the CodeGen) can handle both cases without
9928 // special case code.
9931 // The form of initialization (using parentheses or '=') is generally
9932 // insignificant, but does matter when the entity being initialized has a
9934 if (CXXDirectInit) {
9935 assert(DirectInit && "Call-style initializer must be direct init.");
9936 VDecl->setInitStyle(VarDecl::CallInit);
9937 } else if (DirectInit) {
9938 // This must be list-initialization. No other way is direct-initialization.
9939 VDecl->setInitStyle(VarDecl::ListInit);
9942 CheckCompleteVariableDeclaration(VDecl);
9945 /// ActOnInitializerError - Given that there was an error parsing an
9946 /// initializer for the given declaration, try to return to some form
9948 void Sema::ActOnInitializerError(Decl *D) {
9949 // Our main concern here is re-establishing invariants like "a
9950 // variable's type is either dependent or complete".
9951 if (!D || D->isInvalidDecl()) return;
9953 VarDecl *VD = dyn_cast<VarDecl>(D);
9956 // Auto types are meaningless if we can't make sense of the initializer.
9957 if (ParsingInitForAutoVars.count(D)) {
9958 D->setInvalidDecl();
9962 QualType Ty = VD->getType();
9963 if (Ty->isDependentType()) return;
9965 // Require a complete type.
9966 if (RequireCompleteType(VD->getLocation(),
9967 Context.getBaseElementType(Ty),
9968 diag::err_typecheck_decl_incomplete_type)) {
9969 VD->setInvalidDecl();
9973 // Require a non-abstract type.
9974 if (RequireNonAbstractType(VD->getLocation(), Ty,
9975 diag::err_abstract_type_in_decl,
9976 AbstractVariableType)) {
9977 VD->setInvalidDecl();
9981 // Don't bother complaining about constructors or destructors,
9985 void Sema::ActOnUninitializedDecl(Decl *RealDecl,
9986 bool TypeMayContainAuto) {
9987 // If there is no declaration, there was an error parsing it. Just ignore it.
9991 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) {
9992 QualType Type = Var->getType();
9994 // C++11 [dcl.spec.auto]p3
9995 if (TypeMayContainAuto && Type->getContainedAutoType()) {
9996 Diag(Var->getLocation(), diag::err_auto_var_requires_init)
9997 << Var->getDeclName() << Type;
9998 Var->setInvalidDecl();
10002 // C++11 [class.static.data]p3: A static data member can be declared with
10003 // the constexpr specifier; if so, its declaration shall specify
10004 // a brace-or-equal-initializer.
10005 // C++11 [dcl.constexpr]p1: The constexpr specifier shall be applied only to
10006 // the definition of a variable [...] or the declaration of a static data
10008 if (Var->isConstexpr() && !Var->isThisDeclarationADefinition()) {
10009 if (Var->isStaticDataMember()) {
10010 // C++1z removes the relevant rule; the in-class declaration is always
10011 // a definition there.
10012 if (!getLangOpts().CPlusPlus1z) {
10013 Diag(Var->getLocation(),
10014 diag::err_constexpr_static_mem_var_requires_init)
10015 << Var->getDeclName();
10016 Var->setInvalidDecl();
10020 Diag(Var->getLocation(), diag::err_invalid_constexpr_var_decl);
10021 Var->setInvalidDecl();
10026 // C++ Concepts TS [dcl.spec.concept]p1: [...] A variable template
10027 // definition having the concept specifier is called a variable concept. A
10028 // concept definition refers to [...] a variable concept and its initializer.
10029 if (VarTemplateDecl *VTD = Var->getDescribedVarTemplate()) {
10030 if (VTD->isConcept()) {
10031 Diag(Var->getLocation(), diag::err_var_concept_not_initialized);
10032 Var->setInvalidDecl();
10037 // OpenCL v1.1 s6.5.3: variables declared in the constant address space must
10039 if (!Var->isInvalidDecl() &&
10040 Var->getType().getAddressSpace() == LangAS::opencl_constant &&
10041 Var->getStorageClass() != SC_Extern && !Var->getInit()) {
10042 Diag(Var->getLocation(), diag::err_opencl_constant_no_init);
10043 Var->setInvalidDecl();
10047 switch (Var->isThisDeclarationADefinition()) {
10048 case VarDecl::Definition:
10049 if (!Var->isStaticDataMember() || !Var->getAnyInitializer())
10052 // We have an out-of-line definition of a static data member
10053 // that has an in-class initializer, so we type-check this like
10058 case VarDecl::DeclarationOnly:
10059 // It's only a declaration.
10061 // Block scope. C99 6.7p7: If an identifier for an object is
10062 // declared with no linkage (C99 6.2.2p6), the type for the
10063 // object shall be complete.
10064 if (!Type->isDependentType() && Var->isLocalVarDecl() &&
10065 !Var->hasLinkage() && !Var->isInvalidDecl() &&
10066 RequireCompleteType(Var->getLocation(), Type,
10067 diag::err_typecheck_decl_incomplete_type))
10068 Var->setInvalidDecl();
10070 // Make sure that the type is not abstract.
10071 if (!Type->isDependentType() && !Var->isInvalidDecl() &&
10072 RequireNonAbstractType(Var->getLocation(), Type,
10073 diag::err_abstract_type_in_decl,
10074 AbstractVariableType))
10075 Var->setInvalidDecl();
10076 if (!Type->isDependentType() && !Var->isInvalidDecl() &&
10077 Var->getStorageClass() == SC_PrivateExtern) {
10078 Diag(Var->getLocation(), diag::warn_private_extern);
10079 Diag(Var->getLocation(), diag::note_private_extern);
10084 case VarDecl::TentativeDefinition:
10085 // File scope. C99 6.9.2p2: A declaration of an identifier for an
10086 // object that has file scope without an initializer, and without a
10087 // storage-class specifier or with the storage-class specifier "static",
10088 // constitutes a tentative definition. Note: A tentative definition with
10089 // external linkage is valid (C99 6.2.2p5).
10090 if (!Var->isInvalidDecl()) {
10091 if (const IncompleteArrayType *ArrayT
10092 = Context.getAsIncompleteArrayType(Type)) {
10093 if (RequireCompleteType(Var->getLocation(),
10094 ArrayT->getElementType(),
10095 diag::err_illegal_decl_array_incomplete_type))
10096 Var->setInvalidDecl();
10097 } else if (Var->getStorageClass() == SC_Static) {
10098 // C99 6.9.2p3: If the declaration of an identifier for an object is
10099 // a tentative definition and has internal linkage (C99 6.2.2p3), the
10100 // declared type shall not be an incomplete type.
10101 // NOTE: code such as the following
10102 // static struct s;
10103 // struct s { int a; };
10104 // is accepted by gcc. Hence here we issue a warning instead of
10105 // an error and we do not invalidate the static declaration.
10106 // NOTE: to avoid multiple warnings, only check the first declaration.
10107 if (Var->isFirstDecl())
10108 RequireCompleteType(Var->getLocation(), Type,
10109 diag::ext_typecheck_decl_incomplete_type);
10113 // Record the tentative definition; we're done.
10114 if (!Var->isInvalidDecl())
10115 TentativeDefinitions.push_back(Var);
10119 // Provide a specific diagnostic for uninitialized variable
10120 // definitions with incomplete array type.
10121 if (Type->isIncompleteArrayType()) {
10122 Diag(Var->getLocation(),
10123 diag::err_typecheck_incomplete_array_needs_initializer);
10124 Var->setInvalidDecl();
10128 // Provide a specific diagnostic for uninitialized variable
10129 // definitions with reference type.
10130 if (Type->isReferenceType()) {
10131 Diag(Var->getLocation(), diag::err_reference_var_requires_init)
10132 << Var->getDeclName()
10133 << SourceRange(Var->getLocation(), Var->getLocation());
10134 Var->setInvalidDecl();
10138 // Do not attempt to type-check the default initializer for a
10139 // variable with dependent type.
10140 if (Type->isDependentType())
10143 if (Var->isInvalidDecl())
10146 if (!Var->hasAttr<AliasAttr>()) {
10147 if (RequireCompleteType(Var->getLocation(),
10148 Context.getBaseElementType(Type),
10149 diag::err_typecheck_decl_incomplete_type)) {
10150 Var->setInvalidDecl();
10157 // The variable can not have an abstract class type.
10158 if (RequireNonAbstractType(Var->getLocation(), Type,
10159 diag::err_abstract_type_in_decl,
10160 AbstractVariableType)) {
10161 Var->setInvalidDecl();
10165 // Check for jumps past the implicit initializer. C++0x
10166 // clarifies that this applies to a "variable with automatic
10167 // storage duration", not a "local variable".
10168 // C++11 [stmt.dcl]p3
10169 // A program that jumps from a point where a variable with automatic
10170 // storage duration is not in scope to a point where it is in scope is
10171 // ill-formed unless the variable has scalar type, class type with a
10172 // trivial default constructor and a trivial destructor, a cv-qualified
10173 // version of one of these types, or an array of one of the preceding
10174 // types and is declared without an initializer.
10175 if (getLangOpts().CPlusPlus && Var->hasLocalStorage()) {
10176 if (const RecordType *Record
10177 = Context.getBaseElementType(Type)->getAs<RecordType>()) {
10178 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record->getDecl());
10179 // Mark the function for further checking even if the looser rules of
10180 // C++11 do not require such checks, so that we can diagnose
10181 // incompatibilities with C++98.
10182 if (!CXXRecord->isPOD())
10183 getCurFunction()->setHasBranchProtectedScope();
10187 // C++03 [dcl.init]p9:
10188 // If no initializer is specified for an object, and the
10189 // object is of (possibly cv-qualified) non-POD class type (or
10190 // array thereof), the object shall be default-initialized; if
10191 // the object is of const-qualified type, the underlying class
10192 // type shall have a user-declared default
10193 // constructor. Otherwise, if no initializer is specified for
10194 // a non- static object, the object and its subobjects, if
10195 // any, have an indeterminate initial value); if the object
10196 // or any of its subobjects are of const-qualified type, the
10197 // program is ill-formed.
10198 // C++0x [dcl.init]p11:
10199 // If no initializer is specified for an object, the object is
10200 // default-initialized; [...].
10201 InitializedEntity Entity = InitializedEntity::InitializeVariable(Var);
10202 InitializationKind Kind
10203 = InitializationKind::CreateDefault(Var->getLocation());
10205 InitializationSequence InitSeq(*this, Entity, Kind, None);
10206 ExprResult Init = InitSeq.Perform(*this, Entity, Kind, None);
10207 if (Init.isInvalid())
10208 Var->setInvalidDecl();
10209 else if (Init.get()) {
10210 Var->setInit(MaybeCreateExprWithCleanups(Init.get()));
10211 // This is important for template substitution.
10212 Var->setInitStyle(VarDecl::CallInit);
10215 CheckCompleteVariableDeclaration(Var);
10219 void Sema::ActOnCXXForRangeDecl(Decl *D) {
10220 // If there is no declaration, there was an error parsing it. Ignore it.
10224 VarDecl *VD = dyn_cast<VarDecl>(D);
10226 Diag(D->getLocation(), diag::err_for_range_decl_must_be_var);
10227 D->setInvalidDecl();
10231 VD->setCXXForRangeDecl(true);
10233 // for-range-declaration cannot be given a storage class specifier.
10235 switch (VD->getStorageClass()) {
10244 case SC_PrivateExtern:
10255 Diag(VD->getOuterLocStart(), diag::err_for_range_storage_class)
10256 << VD->getDeclName() << Error;
10257 D->setInvalidDecl();
10262 Sema::ActOnCXXForRangeIdentifier(Scope *S, SourceLocation IdentLoc,
10263 IdentifierInfo *Ident,
10264 ParsedAttributes &Attrs,
10265 SourceLocation AttrEnd) {
10266 // C++1y [stmt.iter]p1:
10267 // A range-based for statement of the form
10268 // for ( for-range-identifier : for-range-initializer ) statement
10269 // is equivalent to
10270 // for ( auto&& for-range-identifier : for-range-initializer ) statement
10271 DeclSpec DS(Attrs.getPool().getFactory());
10273 const char *PrevSpec;
10275 DS.SetTypeSpecType(DeclSpec::TST_auto, IdentLoc, PrevSpec, DiagID,
10276 getPrintingPolicy());
10278 Declarator D(DS, Declarator::ForContext);
10279 D.SetIdentifier(Ident, IdentLoc);
10280 D.takeAttributes(Attrs, AttrEnd);
10282 ParsedAttributes EmptyAttrs(Attrs.getPool().getFactory());
10283 D.AddTypeInfo(DeclaratorChunk::getReference(0, IdentLoc, /*lvalue*/false),
10284 EmptyAttrs, IdentLoc);
10285 Decl *Var = ActOnDeclarator(S, D);
10286 cast<VarDecl>(Var)->setCXXForRangeDecl(true);
10287 FinalizeDeclaration(Var);
10288 return ActOnDeclStmt(FinalizeDeclaratorGroup(S, DS, Var), IdentLoc,
10289 AttrEnd.isValid() ? AttrEnd : IdentLoc);
10292 void Sema::CheckCompleteVariableDeclaration(VarDecl *var) {
10293 if (var->isInvalidDecl()) return;
10295 if (getLangOpts().OpenCL) {
10296 // OpenCL v2.0 s6.12.5 - Every block variable declaration must have an
10298 if (var->getTypeSourceInfo()->getType()->isBlockPointerType() &&
10300 Diag(var->getLocation(), diag::err_opencl_invalid_block_declaration)
10302 var->setInvalidDecl();
10307 // In Objective-C, don't allow jumps past the implicit initialization of a
10308 // local retaining variable.
10309 if (getLangOpts().ObjC1 &&
10310 var->hasLocalStorage()) {
10311 switch (var->getType().getObjCLifetime()) {
10312 case Qualifiers::OCL_None:
10313 case Qualifiers::OCL_ExplicitNone:
10314 case Qualifiers::OCL_Autoreleasing:
10317 case Qualifiers::OCL_Weak:
10318 case Qualifiers::OCL_Strong:
10319 getCurFunction()->setHasBranchProtectedScope();
10324 // Warn about externally-visible variables being defined without a
10325 // prior declaration. We only want to do this for global
10326 // declarations, but we also specifically need to avoid doing it for
10327 // class members because the linkage of an anonymous class can
10328 // change if it's later given a typedef name.
10329 if (var->isThisDeclarationADefinition() &&
10330 var->getDeclContext()->getRedeclContext()->isFileContext() &&
10331 var->isExternallyVisible() && var->hasLinkage() &&
10332 !getDiagnostics().isIgnored(diag::warn_missing_variable_declarations,
10333 var->getLocation())) {
10334 // Find a previous declaration that's not a definition.
10335 VarDecl *prev = var->getPreviousDecl();
10336 while (prev && prev->isThisDeclarationADefinition())
10337 prev = prev->getPreviousDecl();
10340 Diag(var->getLocation(), diag::warn_missing_variable_declarations) << var;
10343 if (var->getTLSKind() == VarDecl::TLS_Static) {
10344 const Expr *Culprit;
10345 if (var->getType().isDestructedType()) {
10346 // GNU C++98 edits for __thread, [basic.start.term]p3:
10347 // The type of an object with thread storage duration shall not
10348 // have a non-trivial destructor.
10349 Diag(var->getLocation(), diag::err_thread_nontrivial_dtor);
10350 if (getLangOpts().CPlusPlus11)
10351 Diag(var->getLocation(), diag::note_use_thread_local);
10352 } else if (getLangOpts().CPlusPlus && var->hasInit() &&
10353 !var->getInit()->isConstantInitializer(
10354 Context, var->getType()->isReferenceType(), &Culprit)) {
10355 // GNU C++98 edits for __thread, [basic.start.init]p4:
10356 // An object of thread storage duration shall not require dynamic
10358 // FIXME: Need strict checking here.
10359 Diag(Culprit->getExprLoc(), diag::err_thread_dynamic_init)
10360 << Culprit->getSourceRange();
10361 if (getLangOpts().CPlusPlus11)
10362 Diag(var->getLocation(), diag::note_use_thread_local);
10366 // Apply section attributes and pragmas to global variables.
10367 bool GlobalStorage = var->hasGlobalStorage();
10368 if (GlobalStorage && var->isThisDeclarationADefinition() &&
10369 ActiveTemplateInstantiations.empty()) {
10370 PragmaStack<StringLiteral *> *Stack = nullptr;
10371 int SectionFlags = ASTContext::PSF_Implicit | ASTContext::PSF_Read;
10372 if (var->getType().isConstQualified())
10373 Stack = &ConstSegStack;
10374 else if (!var->getInit()) {
10375 Stack = &BSSSegStack;
10376 SectionFlags |= ASTContext::PSF_Write;
10378 Stack = &DataSegStack;
10379 SectionFlags |= ASTContext::PSF_Write;
10381 if (Stack->CurrentValue && !var->hasAttr<SectionAttr>()) {
10382 var->addAttr(SectionAttr::CreateImplicit(
10383 Context, SectionAttr::Declspec_allocate,
10384 Stack->CurrentValue->getString(), Stack->CurrentPragmaLocation));
10386 if (const SectionAttr *SA = var->getAttr<SectionAttr>())
10387 if (UnifySection(SA->getName(), SectionFlags, var))
10388 var->dropAttr<SectionAttr>();
10390 // Apply the init_seg attribute if this has an initializer. If the
10391 // initializer turns out to not be dynamic, we'll end up ignoring this
10393 if (CurInitSeg && var->getInit())
10394 var->addAttr(InitSegAttr::CreateImplicit(Context, CurInitSeg->getString(),
10398 // All the following checks are C++ only.
10399 if (!getLangOpts().CPlusPlus) return;
10401 QualType type = var->getType();
10402 if (type->isDependentType()) return;
10404 // __block variables might require us to capture a copy-initializer.
10405 if (var->hasAttr<BlocksAttr>()) {
10406 // It's currently invalid to ever have a __block variable with an
10407 // array type; should we diagnose that here?
10409 // Regardless, we don't want to ignore array nesting when
10410 // constructing this copy.
10411 if (type->isStructureOrClassType()) {
10412 EnterExpressionEvaluationContext scope(*this, PotentiallyEvaluated);
10413 SourceLocation poi = var->getLocation();
10414 Expr *varRef =new (Context) DeclRefExpr(var, false, type, VK_LValue, poi);
10416 = PerformMoveOrCopyInitialization(
10417 InitializedEntity::InitializeBlock(poi, type, false),
10418 var, var->getType(), varRef, /*AllowNRVO=*/true);
10419 if (!result.isInvalid()) {
10420 result = MaybeCreateExprWithCleanups(result);
10421 Expr *init = result.getAs<Expr>();
10422 Context.setBlockVarCopyInits(var, init);
10427 Expr *Init = var->getInit();
10428 bool IsGlobal = GlobalStorage && !var->isStaticLocal();
10429 QualType baseType = Context.getBaseElementType(type);
10431 if (!var->getDeclContext()->isDependentContext() &&
10432 Init && !Init->isValueDependent()) {
10433 if (IsGlobal && !var->isConstexpr() &&
10434 !getDiagnostics().isIgnored(diag::warn_global_constructor,
10435 var->getLocation())) {
10436 // Warn about globals which don't have a constant initializer. Don't
10437 // warn about globals with a non-trivial destructor because we already
10438 // warned about them.
10439 CXXRecordDecl *RD = baseType->getAsCXXRecordDecl();
10440 if (!(RD && !RD->hasTrivialDestructor()) &&
10441 !Init->isConstantInitializer(Context, baseType->isReferenceType()))
10442 Diag(var->getLocation(), diag::warn_global_constructor)
10443 << Init->getSourceRange();
10446 if (var->isConstexpr()) {
10447 SmallVector<PartialDiagnosticAt, 8> Notes;
10448 if (!var->evaluateValue(Notes) || !var->isInitICE()) {
10449 SourceLocation DiagLoc = var->getLocation();
10450 // If the note doesn't add any useful information other than a source
10451 // location, fold it into the primary diagnostic.
10452 if (Notes.size() == 1 && Notes[0].second.getDiagID() ==
10453 diag::note_invalid_subexpr_in_const_expr) {
10454 DiagLoc = Notes[0].first;
10457 Diag(DiagLoc, diag::err_constexpr_var_requires_const_init)
10458 << var << Init->getSourceRange();
10459 for (unsigned I = 0, N = Notes.size(); I != N; ++I)
10460 Diag(Notes[I].first, Notes[I].second);
10462 } else if (var->isUsableInConstantExpressions(Context)) {
10463 // Check whether the initializer of a const variable of integral or
10464 // enumeration type is an ICE now, since we can't tell whether it was
10465 // initialized by a constant expression if we check later.
10466 var->checkInitIsICE();
10470 // Require the destructor.
10471 if (const RecordType *recordType = baseType->getAs<RecordType>())
10472 FinalizeVarWithDestructor(var, recordType);
10475 /// \brief Determines if a variable's alignment is dependent.
10476 static bool hasDependentAlignment(VarDecl *VD) {
10477 if (VD->getType()->isDependentType())
10479 for (auto *I : VD->specific_attrs<AlignedAttr>())
10480 if (I->isAlignmentDependent())
10485 /// FinalizeDeclaration - called by ParseDeclarationAfterDeclarator to perform
10486 /// any semantic actions necessary after any initializer has been attached.
10488 Sema::FinalizeDeclaration(Decl *ThisDecl) {
10489 // Note that we are no longer parsing the initializer for this declaration.
10490 ParsingInitForAutoVars.erase(ThisDecl);
10492 VarDecl *VD = dyn_cast_or_null<VarDecl>(ThisDecl);
10496 checkAttributesAfterMerging(*this, *VD);
10498 // Perform TLS alignment check here after attributes attached to the variable
10499 // which may affect the alignment have been processed. Only perform the check
10500 // if the target has a maximum TLS alignment (zero means no constraints).
10501 if (unsigned MaxAlign = Context.getTargetInfo().getMaxTLSAlign()) {
10502 // Protect the check so that it's not performed on dependent types and
10503 // dependent alignments (we can't determine the alignment in that case).
10504 if (VD->getTLSKind() && !hasDependentAlignment(VD)) {
10505 CharUnits MaxAlignChars = Context.toCharUnitsFromBits(MaxAlign);
10506 if (Context.getDeclAlign(VD) > MaxAlignChars) {
10507 Diag(VD->getLocation(), diag::err_tls_var_aligned_over_maximum)
10508 << (unsigned)Context.getDeclAlign(VD).getQuantity() << VD
10509 << (unsigned)MaxAlignChars.getQuantity();
10514 if (VD->isStaticLocal()) {
10515 if (FunctionDecl *FD =
10516 dyn_cast_or_null<FunctionDecl>(VD->getParentFunctionOrMethod())) {
10517 // Static locals inherit dll attributes from their function.
10518 if (Attr *A = getDLLAttr(FD)) {
10519 auto *NewAttr = cast<InheritableAttr>(A->clone(getASTContext()));
10520 NewAttr->setInherited(true);
10521 VD->addAttr(NewAttr);
10523 // CUDA E.2.9.4: Within the body of a __device__ or __global__
10524 // function, only __shared__ variables may be declared with
10525 // static storage class.
10526 if (getLangOpts().CUDA && getLangOpts().CUDAIsDevice &&
10527 (FD->hasAttr<CUDADeviceAttr>() || FD->hasAttr<CUDAGlobalAttr>()) &&
10528 !VD->hasAttr<CUDASharedAttr>()) {
10529 Diag(VD->getLocation(), diag::err_device_static_local_var);
10530 VD->setInvalidDecl();
10535 // Perform check for initializers of device-side global variables.
10536 // CUDA allows empty constructors as initializers (see E.2.3.1, CUDA
10537 // 7.5). We must also apply the same checks to all __shared__
10538 // variables whether they are local or not. CUDA also allows
10539 // constant initializers for __constant__ and __device__ variables.
10540 if (getLangOpts().CUDA && getLangOpts().CUDAIsDevice) {
10541 const Expr *Init = VD->getInit();
10542 if (Init && VD->hasGlobalStorage() &&
10543 (VD->hasAttr<CUDADeviceAttr>() || VD->hasAttr<CUDAConstantAttr>() ||
10544 VD->hasAttr<CUDASharedAttr>())) {
10545 assert((!VD->isStaticLocal() || VD->hasAttr<CUDASharedAttr>()));
10546 bool AllowedInit = false;
10547 if (const CXXConstructExpr *CE = dyn_cast<CXXConstructExpr>(Init))
10549 isEmptyCudaConstructor(VD->getLocation(), CE->getConstructor());
10550 // We'll allow constant initializers even if it's a non-empty
10551 // constructor according to CUDA rules. This deviates from NVCC,
10552 // but allows us to handle things like constexpr constructors.
10553 if (!AllowedInit &&
10554 (VD->hasAttr<CUDADeviceAttr>() || VD->hasAttr<CUDAConstantAttr>()))
10555 AllowedInit = VD->getInit()->isConstantInitializer(
10556 Context, VD->getType()->isReferenceType());
10558 // Also make sure that destructor, if there is one, is empty.
10560 if (CXXRecordDecl *RD = VD->getType()->getAsCXXRecordDecl())
10562 isEmptyCudaDestructor(VD->getLocation(), RD->getDestructor());
10564 if (!AllowedInit) {
10565 Diag(VD->getLocation(), VD->hasAttr<CUDASharedAttr>()
10566 ? diag::err_shared_var_init
10567 : diag::err_dynamic_var_init)
10568 << Init->getSourceRange();
10569 VD->setInvalidDecl();
10574 // Grab the dllimport or dllexport attribute off of the VarDecl.
10575 const InheritableAttr *DLLAttr = getDLLAttr(VD);
10577 // Imported static data members cannot be defined out-of-line.
10578 if (const auto *IA = dyn_cast_or_null<DLLImportAttr>(DLLAttr)) {
10579 if (VD->isStaticDataMember() && VD->isOutOfLine() &&
10580 VD->isThisDeclarationADefinition()) {
10581 // We allow definitions of dllimport class template static data members
10583 CXXRecordDecl *Context =
10584 cast<CXXRecordDecl>(VD->getFirstDecl()->getDeclContext());
10585 bool IsClassTemplateMember =
10586 isa<ClassTemplatePartialSpecializationDecl>(Context) ||
10587 Context->getDescribedClassTemplate();
10589 Diag(VD->getLocation(),
10590 IsClassTemplateMember
10591 ? diag::warn_attribute_dllimport_static_field_definition
10592 : diag::err_attribute_dllimport_static_field_definition);
10593 Diag(IA->getLocation(), diag::note_attribute);
10594 if (!IsClassTemplateMember)
10595 VD->setInvalidDecl();
10599 // dllimport/dllexport variables cannot be thread local, their TLS index
10600 // isn't exported with the variable.
10601 if (DLLAttr && VD->getTLSKind()) {
10602 auto *F = dyn_cast_or_null<FunctionDecl>(VD->getParentFunctionOrMethod());
10603 if (F && getDLLAttr(F)) {
10604 assert(VD->isStaticLocal());
10605 // But if this is a static local in a dlimport/dllexport function, the
10606 // function will never be inlined, which means the var would never be
10607 // imported, so having it marked import/export is safe.
10609 Diag(VD->getLocation(), diag::err_attribute_dll_thread_local) << VD
10611 VD->setInvalidDecl();
10615 if (UsedAttr *Attr = VD->getAttr<UsedAttr>()) {
10616 if (!Attr->isInherited() && !VD->isThisDeclarationADefinition()) {
10617 Diag(Attr->getLocation(), diag::warn_attribute_ignored) << Attr;
10618 VD->dropAttr<UsedAttr>();
10622 const DeclContext *DC = VD->getDeclContext();
10623 // If there's a #pragma GCC visibility in scope, and this isn't a class
10624 // member, set the visibility of this variable.
10625 if (DC->getRedeclContext()->isFileContext() && VD->isExternallyVisible())
10626 AddPushedVisibilityAttribute(VD);
10628 // FIXME: Warn on unused templates.
10629 if (VD->isFileVarDecl() && !VD->getDescribedVarTemplate() &&
10630 !isa<VarTemplatePartialSpecializationDecl>(VD))
10631 MarkUnusedFileScopedDecl(VD);
10633 // Now we have parsed the initializer and can update the table of magic
10635 if (!VD->hasAttr<TypeTagForDatatypeAttr>() ||
10636 !VD->getType()->isIntegralOrEnumerationType())
10639 for (const auto *I : ThisDecl->specific_attrs<TypeTagForDatatypeAttr>()) {
10640 const Expr *MagicValueExpr = VD->getInit();
10641 if (!MagicValueExpr) {
10644 llvm::APSInt MagicValueInt;
10645 if (!MagicValueExpr->isIntegerConstantExpr(MagicValueInt, Context)) {
10646 Diag(I->getRange().getBegin(),
10647 diag::err_type_tag_for_datatype_not_ice)
10648 << LangOpts.CPlusPlus << MagicValueExpr->getSourceRange();
10651 if (MagicValueInt.getActiveBits() > 64) {
10652 Diag(I->getRange().getBegin(),
10653 diag::err_type_tag_for_datatype_too_large)
10654 << LangOpts.CPlusPlus << MagicValueExpr->getSourceRange();
10657 uint64_t MagicValue = MagicValueInt.getZExtValue();
10658 RegisterTypeTagForDatatype(I->getArgumentKind(),
10660 I->getMatchingCType(),
10661 I->getLayoutCompatible(),
10662 I->getMustBeNull());
10666 Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS,
10667 ArrayRef<Decl *> Group) {
10668 SmallVector<Decl*, 8> Decls;
10670 if (DS.isTypeSpecOwned())
10671 Decls.push_back(DS.getRepAsDecl());
10673 DeclaratorDecl *FirstDeclaratorInGroup = nullptr;
10674 for (unsigned i = 0, e = Group.size(); i != e; ++i)
10675 if (Decl *D = Group[i]) {
10676 if (DeclaratorDecl *DD = dyn_cast<DeclaratorDecl>(D))
10677 if (!FirstDeclaratorInGroup)
10678 FirstDeclaratorInGroup = DD;
10679 Decls.push_back(D);
10682 if (DeclSpec::isDeclRep(DS.getTypeSpecType())) {
10683 if (TagDecl *Tag = dyn_cast_or_null<TagDecl>(DS.getRepAsDecl())) {
10684 handleTagNumbering(Tag, S);
10685 if (FirstDeclaratorInGroup && !Tag->hasNameForLinkage() &&
10686 getLangOpts().CPlusPlus)
10687 Context.addDeclaratorForUnnamedTagDecl(Tag, FirstDeclaratorInGroup);
10691 return BuildDeclaratorGroup(Decls, DS.containsPlaceholderType());
10694 /// BuildDeclaratorGroup - convert a list of declarations into a declaration
10695 /// group, performing any necessary semantic checking.
10696 Sema::DeclGroupPtrTy
10697 Sema::BuildDeclaratorGroup(MutableArrayRef<Decl *> Group,
10698 bool TypeMayContainAuto) {
10699 // C++0x [dcl.spec.auto]p7:
10700 // If the type deduced for the template parameter U is not the same in each
10701 // deduction, the program is ill-formed.
10702 // FIXME: When initializer-list support is added, a distinction is needed
10703 // between the deduced type U and the deduced type which 'auto' stands for.
10704 // auto a = 0, b = { 1, 2, 3 };
10705 // is legal because the deduced type U is 'int' in both cases.
10706 if (TypeMayContainAuto && Group.size() > 1) {
10708 CanQualType DeducedCanon;
10709 VarDecl *DeducedDecl = nullptr;
10710 for (unsigned i = 0, e = Group.size(); i != e; ++i) {
10711 if (VarDecl *D = dyn_cast<VarDecl>(Group[i])) {
10712 AutoType *AT = D->getType()->getContainedAutoType();
10713 // Don't reissue diagnostics when instantiating a template.
10714 if (AT && D->isInvalidDecl())
10716 QualType U = AT ? AT->getDeducedType() : QualType();
10718 CanQualType UCanon = Context.getCanonicalType(U);
10719 if (Deduced.isNull()) {
10721 DeducedCanon = UCanon;
10723 } else if (DeducedCanon != UCanon) {
10724 Diag(D->getTypeSourceInfo()->getTypeLoc().getBeginLoc(),
10725 diag::err_auto_different_deductions)
10726 << (unsigned)AT->getKeyword()
10727 << Deduced << DeducedDecl->getDeclName()
10728 << U << D->getDeclName()
10729 << DeducedDecl->getInit()->getSourceRange()
10730 << D->getInit()->getSourceRange();
10731 D->setInvalidDecl();
10739 ActOnDocumentableDecls(Group);
10741 return DeclGroupPtrTy::make(
10742 DeclGroupRef::Create(Context, Group.data(), Group.size()));
10745 void Sema::ActOnDocumentableDecl(Decl *D) {
10746 ActOnDocumentableDecls(D);
10749 void Sema::ActOnDocumentableDecls(ArrayRef<Decl *> Group) {
10750 // Don't parse the comment if Doxygen diagnostics are ignored.
10751 if (Group.empty() || !Group[0])
10754 if (Diags.isIgnored(diag::warn_doc_param_not_found,
10755 Group[0]->getLocation()) &&
10756 Diags.isIgnored(diag::warn_unknown_comment_command_name,
10757 Group[0]->getLocation()))
10760 if (Group.size() >= 2) {
10761 // This is a decl group. Normally it will contain only declarations
10762 // produced from declarator list. But in case we have any definitions or
10763 // additional declaration references:
10764 // 'typedef struct S {} S;'
10765 // 'typedef struct S *S;'
10767 // FinalizeDeclaratorGroup adds these as separate declarations.
10768 Decl *MaybeTagDecl = Group[0];
10769 if (MaybeTagDecl && isa<TagDecl>(MaybeTagDecl)) {
10770 Group = Group.slice(1);
10774 // See if there are any new comments that are not attached to a decl.
10775 ArrayRef<RawComment *> Comments = Context.getRawCommentList().getComments();
10776 if (!Comments.empty() &&
10777 !Comments.back()->isAttached()) {
10778 // There is at least one comment that not attached to a decl.
10779 // Maybe it should be attached to one of these decls?
10781 // Note that this way we pick up not only comments that precede the
10782 // declaration, but also comments that *follow* the declaration -- thanks to
10783 // the lookahead in the lexer: we've consumed the semicolon and looked
10784 // ahead through comments.
10785 for (unsigned i = 0, e = Group.size(); i != e; ++i)
10786 Context.getCommentForDecl(Group[i], &PP);
10790 /// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator()
10791 /// to introduce parameters into function prototype scope.
10792 Decl *Sema::ActOnParamDeclarator(Scope *S, Declarator &D) {
10793 const DeclSpec &DS = D.getDeclSpec();
10795 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'.
10797 // C++03 [dcl.stc]p2 also permits 'auto'.
10798 StorageClass SC = SC_None;
10799 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) {
10801 } else if (getLangOpts().CPlusPlus &&
10802 DS.getStorageClassSpec() == DeclSpec::SCS_auto) {
10804 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) {
10805 Diag(DS.getStorageClassSpecLoc(),
10806 diag::err_invalid_storage_class_in_func_decl);
10807 D.getMutableDeclSpec().ClearStorageClassSpecs();
10810 if (DeclSpec::TSCS TSCS = DS.getThreadStorageClassSpec())
10811 Diag(DS.getThreadStorageClassSpecLoc(), diag::err_invalid_thread)
10812 << DeclSpec::getSpecifierName(TSCS);
10813 if (DS.isInlineSpecified())
10814 Diag(DS.getInlineSpecLoc(), diag::err_inline_non_function)
10815 << getLangOpts().CPlusPlus1z;
10816 if (DS.isConstexprSpecified())
10817 Diag(DS.getConstexprSpecLoc(), diag::err_invalid_constexpr)
10819 if (DS.isConceptSpecified())
10820 Diag(DS.getConceptSpecLoc(), diag::err_concept_wrong_decl_kind);
10822 DiagnoseFunctionSpecifiers(DS);
10824 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S);
10825 QualType parmDeclType = TInfo->getType();
10827 if (getLangOpts().CPlusPlus) {
10828 // Check that there are no default arguments inside the type of this
10830 CheckExtraCXXDefaultArguments(D);
10832 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1).
10833 if (D.getCXXScopeSpec().isSet()) {
10834 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator)
10835 << D.getCXXScopeSpec().getRange();
10836 D.getCXXScopeSpec().clear();
10840 // Ensure we have a valid name
10841 IdentifierInfo *II = nullptr;
10843 II = D.getIdentifier();
10845 Diag(D.getIdentifierLoc(), diag::err_bad_parameter_name)
10846 << GetNameForDeclarator(D).getName();
10847 D.setInvalidType(true);
10851 // Check for redeclaration of parameters, e.g. int foo(int x, int x);
10853 LookupResult R(*this, II, D.getIdentifierLoc(), LookupOrdinaryName,
10856 if (R.isSingleResult()) {
10857 NamedDecl *PrevDecl = R.getFoundDecl();
10858 if (PrevDecl->isTemplateParameter()) {
10859 // Maybe we will complain about the shadowed template parameter.
10860 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl);
10861 // Just pretend that we didn't see the previous declaration.
10862 PrevDecl = nullptr;
10863 } else if (S->isDeclScope(PrevDecl)) {
10864 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II;
10865 Diag(PrevDecl->getLocation(), diag::note_previous_declaration);
10867 // Recover by removing the name
10869 D.SetIdentifier(nullptr, D.getIdentifierLoc());
10870 D.setInvalidType(true);
10875 // Temporarily put parameter variables in the translation unit, not
10876 // the enclosing context. This prevents them from accidentally
10877 // looking like class members in C++.
10878 ParmVarDecl *New = CheckParameter(Context.getTranslationUnitDecl(),
10880 D.getIdentifierLoc(), II,
10881 parmDeclType, TInfo,
10884 if (D.isInvalidType())
10885 New->setInvalidDecl();
10887 assert(S->isFunctionPrototypeScope());
10888 assert(S->getFunctionPrototypeDepth() >= 1);
10889 New->setScopeInfo(S->getFunctionPrototypeDepth() - 1,
10890 S->getNextFunctionPrototypeIndex());
10892 // Add the parameter declaration into this scope.
10895 IdResolver.AddDecl(New);
10897 ProcessDeclAttributes(S, New, D);
10899 if (D.getDeclSpec().isModulePrivateSpecified())
10900 Diag(New->getLocation(), diag::err_module_private_local)
10901 << 1 << New->getDeclName()
10902 << SourceRange(D.getDeclSpec().getModulePrivateSpecLoc())
10903 << FixItHint::CreateRemoval(D.getDeclSpec().getModulePrivateSpecLoc());
10905 if (New->hasAttr<BlocksAttr>()) {
10906 Diag(New->getLocation(), diag::err_block_on_nonlocal);
10911 /// \brief Synthesizes a variable for a parameter arising from a
10913 ParmVarDecl *Sema::BuildParmVarDeclForTypedef(DeclContext *DC,
10914 SourceLocation Loc,
10916 /* FIXME: setting StartLoc == Loc.
10917 Would it be worth to modify callers so as to provide proper source
10918 location for the unnamed parameters, embedding the parameter's type? */
10919 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, Loc, Loc, nullptr,
10920 T, Context.getTrivialTypeSourceInfo(T, Loc),
10922 Param->setImplicit();
10926 void Sema::DiagnoseUnusedParameters(ArrayRef<ParmVarDecl *> Parameters) {
10927 // Don't diagnose unused-parameter errors in template instantiations; we
10928 // will already have done so in the template itself.
10929 if (!ActiveTemplateInstantiations.empty())
10932 for (const ParmVarDecl *Parameter : Parameters) {
10933 if (!Parameter->isReferenced() && Parameter->getDeclName() &&
10934 !Parameter->hasAttr<UnusedAttr>()) {
10935 Diag(Parameter->getLocation(), diag::warn_unused_parameter)
10936 << Parameter->getDeclName();
10941 void Sema::DiagnoseSizeOfParametersAndReturnValue(
10942 ArrayRef<ParmVarDecl *> Parameters, QualType ReturnTy, NamedDecl *D) {
10943 if (LangOpts.NumLargeByValueCopy == 0) // No check.
10946 // Warn if the return value is pass-by-value and larger than the specified
10948 if (!ReturnTy->isDependentType() && ReturnTy.isPODType(Context)) {
10949 unsigned Size = Context.getTypeSizeInChars(ReturnTy).getQuantity();
10950 if (Size > LangOpts.NumLargeByValueCopy)
10951 Diag(D->getLocation(), diag::warn_return_value_size)
10952 << D->getDeclName() << Size;
10955 // Warn if any parameter is pass-by-value and larger than the specified
10957 for (const ParmVarDecl *Parameter : Parameters) {
10958 QualType T = Parameter->getType();
10959 if (T->isDependentType() || !T.isPODType(Context))
10961 unsigned Size = Context.getTypeSizeInChars(T).getQuantity();
10962 if (Size > LangOpts.NumLargeByValueCopy)
10963 Diag(Parameter->getLocation(), diag::warn_parameter_size)
10964 << Parameter->getDeclName() << Size;
10968 ParmVarDecl *Sema::CheckParameter(DeclContext *DC, SourceLocation StartLoc,
10969 SourceLocation NameLoc, IdentifierInfo *Name,
10970 QualType T, TypeSourceInfo *TSInfo,
10972 // In ARC, infer a lifetime qualifier for appropriate parameter types.
10973 if (getLangOpts().ObjCAutoRefCount &&
10974 T.getObjCLifetime() == Qualifiers::OCL_None &&
10975 T->isObjCLifetimeType()) {
10977 Qualifiers::ObjCLifetime lifetime;
10979 // Special cases for arrays:
10980 // - if it's const, use __unsafe_unretained
10981 // - otherwise, it's an error
10982 if (T->isArrayType()) {
10983 if (!T.isConstQualified()) {
10984 DelayedDiagnostics.add(
10985 sema::DelayedDiagnostic::makeForbiddenType(
10986 NameLoc, diag::err_arc_array_param_no_ownership, T, false));
10988 lifetime = Qualifiers::OCL_ExplicitNone;
10990 lifetime = T->getObjCARCImplicitLifetime();
10992 T = Context.getLifetimeQualifiedType(T, lifetime);
10995 ParmVarDecl *New = ParmVarDecl::Create(Context, DC, StartLoc, NameLoc, Name,
10996 Context.getAdjustedParameterType(T),
10997 TSInfo, SC, nullptr);
10999 // Parameters can not be abstract class types.
11000 // For record types, this is done by the AbstractClassUsageDiagnoser once
11001 // the class has been completely parsed.
11002 if (!CurContext->isRecord() &&
11003 RequireNonAbstractType(NameLoc, T, diag::err_abstract_type_in_decl,
11004 AbstractParamType))
11005 New->setInvalidDecl();
11007 // Parameter declarators cannot be interface types. All ObjC objects are
11008 // passed by reference.
11009 if (T->isObjCObjectType()) {
11010 SourceLocation TypeEndLoc =
11011 getLocForEndOfToken(TSInfo->getTypeLoc().getLocEnd());
11013 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T
11014 << FixItHint::CreateInsertion(TypeEndLoc, "*");
11015 T = Context.getObjCObjectPointerType(T);
11019 // ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage
11020 // duration shall not be qualified by an address-space qualifier."
11021 // Since all parameters have automatic store duration, they can not have
11022 // an address space.
11023 if (T.getAddressSpace() != 0) {
11024 // OpenCL allows function arguments declared to be an array of a type
11025 // to be qualified with an address space.
11026 if (!(getLangOpts().OpenCL && T->isArrayType())) {
11027 Diag(NameLoc, diag::err_arg_with_address_space);
11028 New->setInvalidDecl();
11035 void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D,
11036 SourceLocation LocAfterDecls) {
11037 DeclaratorChunk::FunctionTypeInfo &FTI = D.getFunctionTypeInfo();
11039 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared'
11040 // for a K&R function.
11041 if (!FTI.hasPrototype) {
11042 for (int i = FTI.NumParams; i != 0; /* decrement in loop */) {
11044 if (FTI.Params[i].Param == nullptr) {
11045 SmallString<256> Code;
11046 llvm::raw_svector_ostream(Code)
11047 << " int " << FTI.Params[i].Ident->getName() << ";\n";
11048 Diag(FTI.Params[i].IdentLoc, diag::ext_param_not_declared)
11049 << FTI.Params[i].Ident
11050 << FixItHint::CreateInsertion(LocAfterDecls, Code);
11052 // Implicitly declare the argument as type 'int' for lack of a better
11054 AttributeFactory attrs;
11055 DeclSpec DS(attrs);
11056 const char* PrevSpec; // unused
11057 unsigned DiagID; // unused
11058 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.Params[i].IdentLoc, PrevSpec,
11059 DiagID, Context.getPrintingPolicy());
11060 // Use the identifier location for the type source range.
11061 DS.SetRangeStart(FTI.Params[i].IdentLoc);
11062 DS.SetRangeEnd(FTI.Params[i].IdentLoc);
11063 Declarator ParamD(DS, Declarator::KNRTypeListContext);
11064 ParamD.SetIdentifier(FTI.Params[i].Ident, FTI.Params[i].IdentLoc);
11065 FTI.Params[i].Param = ActOnParamDeclarator(S, ParamD);
11072 Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, Declarator &D,
11073 MultiTemplateParamsArg TemplateParameterLists,
11074 SkipBodyInfo *SkipBody) {
11075 assert(getCurFunctionDecl() == nullptr && "Function parsing confused");
11076 assert(D.isFunctionDeclarator() && "Not a function declarator!");
11077 Scope *ParentScope = FnBodyScope->getParent();
11079 D.setFunctionDefinitionKind(FDK_Definition);
11080 Decl *DP = HandleDeclarator(ParentScope, D, TemplateParameterLists);
11081 return ActOnStartOfFunctionDef(FnBodyScope, DP, SkipBody);
11084 void Sema::ActOnFinishInlineFunctionDef(FunctionDecl *D) {
11085 Consumer.HandleInlineFunctionDefinition(D);
11088 static bool ShouldWarnAboutMissingPrototype(const FunctionDecl *FD,
11089 const FunctionDecl*& PossibleZeroParamPrototype) {
11090 // Don't warn about invalid declarations.
11091 if (FD->isInvalidDecl())
11094 // Or declarations that aren't global.
11095 if (!FD->isGlobal())
11098 // Don't warn about C++ member functions.
11099 if (isa<CXXMethodDecl>(FD))
11102 // Don't warn about 'main'.
11106 // Don't warn about inline functions.
11107 if (FD->isInlined())
11110 // Don't warn about function templates.
11111 if (FD->getDescribedFunctionTemplate())
11114 // Don't warn about function template specializations.
11115 if (FD->isFunctionTemplateSpecialization())
11118 // Don't warn for OpenCL kernels.
11119 if (FD->hasAttr<OpenCLKernelAttr>())
11122 // Don't warn on explicitly deleted functions.
11123 if (FD->isDeleted())
11126 bool MissingPrototype = true;
11127 for (const FunctionDecl *Prev = FD->getPreviousDecl();
11128 Prev; Prev = Prev->getPreviousDecl()) {
11129 // Ignore any declarations that occur in function or method
11130 // scope, because they aren't visible from the header.
11131 if (Prev->getLexicalDeclContext()->isFunctionOrMethod())
11134 MissingPrototype = !Prev->getType()->isFunctionProtoType();
11135 if (FD->getNumParams() == 0)
11136 PossibleZeroParamPrototype = Prev;
11140 return MissingPrototype;
11144 Sema::CheckForFunctionRedefinition(FunctionDecl *FD,
11145 const FunctionDecl *EffectiveDefinition,
11146 SkipBodyInfo *SkipBody) {
11147 // Don't complain if we're in GNU89 mode and the previous definition
11148 // was an extern inline function.
11149 const FunctionDecl *Definition = EffectiveDefinition;
11151 if (!FD->isDefined(Definition))
11154 if (canRedefineFunction(Definition, getLangOpts()))
11157 // If we don't have a visible definition of the function, and it's inline or
11158 // a template, skip the new definition.
11159 if (SkipBody && !hasVisibleDefinition(Definition) &&
11160 (Definition->getFormalLinkage() == InternalLinkage ||
11161 Definition->isInlined() ||
11162 Definition->getDescribedFunctionTemplate() ||
11163 Definition->getNumTemplateParameterLists())) {
11164 SkipBody->ShouldSkip = true;
11165 if (auto *TD = Definition->getDescribedFunctionTemplate())
11166 makeMergedDefinitionVisible(TD, FD->getLocation());
11168 makeMergedDefinitionVisible(const_cast<FunctionDecl*>(Definition),
11169 FD->getLocation());
11173 if (getLangOpts().GNUMode && Definition->isInlineSpecified() &&
11174 Definition->getStorageClass() == SC_Extern)
11175 Diag(FD->getLocation(), diag::err_redefinition_extern_inline)
11176 << FD->getDeclName() << getLangOpts().CPlusPlus;
11178 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName();
11180 Diag(Definition->getLocation(), diag::note_previous_definition);
11181 FD->setInvalidDecl();
11184 static void RebuildLambdaScopeInfo(CXXMethodDecl *CallOperator,
11186 CXXRecordDecl *const LambdaClass = CallOperator->getParent();
11188 LambdaScopeInfo *LSI = S.PushLambdaScope();
11189 LSI->CallOperator = CallOperator;
11190 LSI->Lambda = LambdaClass;
11191 LSI->ReturnType = CallOperator->getReturnType();
11192 const LambdaCaptureDefault LCD = LambdaClass->getLambdaCaptureDefault();
11194 if (LCD == LCD_None)
11195 LSI->ImpCaptureStyle = CapturingScopeInfo::ImpCap_None;
11196 else if (LCD == LCD_ByCopy)
11197 LSI->ImpCaptureStyle = CapturingScopeInfo::ImpCap_LambdaByval;
11198 else if (LCD == LCD_ByRef)
11199 LSI->ImpCaptureStyle = CapturingScopeInfo::ImpCap_LambdaByref;
11200 DeclarationNameInfo DNI = CallOperator->getNameInfo();
11202 LSI->IntroducerRange = DNI.getCXXOperatorNameRange();
11203 LSI->Mutable = !CallOperator->isConst();
11205 // Add the captures to the LSI so they can be noted as already
11206 // captured within tryCaptureVar.
11207 auto I = LambdaClass->field_begin();
11208 for (const auto &C : LambdaClass->captures()) {
11209 if (C.capturesVariable()) {
11210 VarDecl *VD = C.getCapturedVar();
11211 if (VD->isInitCapture())
11212 S.CurrentInstantiationScope->InstantiatedLocal(VD, VD);
11213 QualType CaptureType = VD->getType();
11214 const bool ByRef = C.getCaptureKind() == LCK_ByRef;
11215 LSI->addCapture(VD, /*IsBlock*/false, ByRef,
11216 /*RefersToEnclosingVariableOrCapture*/true, C.getLocation(),
11217 /*EllipsisLoc*/C.isPackExpansion()
11218 ? C.getEllipsisLoc() : SourceLocation(),
11219 CaptureType, /*Expr*/ nullptr);
11221 } else if (C.capturesThis()) {
11222 LSI->addThisCapture(/*Nested*/ false, C.getLocation(),
11224 C.getCaptureKind() == LCK_StarThis);
11226 LSI->addVLATypeCapture(C.getLocation(), I->getType());
11232 Decl *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, Decl *D,
11233 SkipBodyInfo *SkipBody) {
11234 // Clear the last template instantiation error context.
11235 LastTemplateInstantiationErrorContext = ActiveTemplateInstantiation();
11239 FunctionDecl *FD = nullptr;
11241 if (FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(D))
11242 FD = FunTmpl->getTemplatedDecl();
11244 FD = cast<FunctionDecl>(D);
11246 // See if this is a redefinition.
11247 if (!FD->isLateTemplateParsed()) {
11248 CheckForFunctionRedefinition(FD, nullptr, SkipBody);
11250 // If we're skipping the body, we're done. Don't enter the scope.
11251 if (SkipBody && SkipBody->ShouldSkip)
11255 // If we are instantiating a generic lambda call operator, push
11256 // a LambdaScopeInfo onto the function stack. But use the information
11257 // that's already been calculated (ActOnLambdaExpr) to prime the current
11258 // LambdaScopeInfo.
11259 // When the template operator is being specialized, the LambdaScopeInfo,
11260 // has to be properly restored so that tryCaptureVariable doesn't try
11261 // and capture any new variables. In addition when calculating potential
11262 // captures during transformation of nested lambdas, it is necessary to
11263 // have the LSI properly restored.
11264 if (isGenericLambdaCallOperatorSpecialization(FD)) {
11265 assert(ActiveTemplateInstantiations.size() &&
11266 "There should be an active template instantiation on the stack "
11267 "when instantiating a generic lambda!");
11268 RebuildLambdaScopeInfo(cast<CXXMethodDecl>(D), *this);
11271 // Enter a new function scope
11272 PushFunctionScope();
11274 // Builtin functions cannot be defined.
11275 if (unsigned BuiltinID = FD->getBuiltinID()) {
11276 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID) &&
11277 !Context.BuiltinInfo.isPredefinedRuntimeFunction(BuiltinID)) {
11278 Diag(FD->getLocation(), diag::err_builtin_definition) << FD;
11279 FD->setInvalidDecl();
11283 // The return type of a function definition must be complete
11284 // (C99 6.9.1p3, C++ [dcl.fct]p6).
11285 QualType ResultType = FD->getReturnType();
11286 if (!ResultType->isDependentType() && !ResultType->isVoidType() &&
11287 !FD->isInvalidDecl() &&
11288 RequireCompleteType(FD->getLocation(), ResultType,
11289 diag::err_func_def_incomplete_result))
11290 FD->setInvalidDecl();
11293 PushDeclContext(FnBodyScope, FD);
11295 // Check the validity of our function parameters
11296 CheckParmsForFunctionDef(FD->parameters(),
11297 /*CheckParameterNames=*/true);
11299 // Introduce our parameters into the function scope
11300 for (auto Param : FD->parameters()) {
11301 Param->setOwningFunction(FD);
11303 // If this has an identifier, add it to the scope stack.
11304 if (Param->getIdentifier() && FnBodyScope) {
11305 CheckShadow(FnBodyScope, Param);
11307 PushOnScopeChains(Param, FnBodyScope);
11311 // If we had any tags defined in the function prototype,
11312 // introduce them into the function scope.
11314 for (ArrayRef<NamedDecl *>::iterator
11315 I = FD->getDeclsInPrototypeScope().begin(),
11316 E = FD->getDeclsInPrototypeScope().end();
11320 // Some of these decls (like enums) may have been pinned to the
11321 // translation unit for lack of a real context earlier. If so, remove
11322 // from the translation unit and reattach to the current context.
11323 if (D->getLexicalDeclContext() == Context.getTranslationUnitDecl()) {
11324 // Is the decl actually in the context?
11325 if (Context.getTranslationUnitDecl()->containsDecl(D))
11326 Context.getTranslationUnitDecl()->removeDecl(D);
11327 // Either way, reassign the lexical decl context to our FunctionDecl.
11328 D->setLexicalDeclContext(CurContext);
11331 // If the decl has a non-null name, make accessible in the current scope.
11332 if (!D->getName().empty())
11333 PushOnScopeChains(D, FnBodyScope, /*AddToContext=*/false);
11335 // Similarly, dive into enums and fish their constants out, making them
11336 // accessible in this scope.
11337 if (auto *ED = dyn_cast<EnumDecl>(D)) {
11338 for (auto *EI : ED->enumerators())
11339 PushOnScopeChains(EI, FnBodyScope, /*AddToContext=*/false);
11344 // Ensure that the function's exception specification is instantiated.
11345 if (const FunctionProtoType *FPT = FD->getType()->getAs<FunctionProtoType>())
11346 ResolveExceptionSpec(D->getLocation(), FPT);
11348 // dllimport cannot be applied to non-inline function definitions.
11349 if (FD->hasAttr<DLLImportAttr>() && !FD->isInlined() &&
11350 !FD->isTemplateInstantiation()) {
11351 assert(!FD->hasAttr<DLLExportAttr>());
11352 Diag(FD->getLocation(), diag::err_attribute_dllimport_function_definition);
11353 FD->setInvalidDecl();
11356 // We want to attach documentation to original Decl (which might be
11357 // a function template).
11358 ActOnDocumentableDecl(D);
11359 if (getCurLexicalContext()->isObjCContainer() &&
11360 getCurLexicalContext()->getDeclKind() != Decl::ObjCCategoryImpl &&
11361 getCurLexicalContext()->getDeclKind() != Decl::ObjCImplementation)
11362 Diag(FD->getLocation(), diag::warn_function_def_in_objc_container);
11367 /// \brief Given the set of return statements within a function body,
11368 /// compute the variables that are subject to the named return value
11371 /// Each of the variables that is subject to the named return value
11372 /// optimization will be marked as NRVO variables in the AST, and any
11373 /// return statement that has a marked NRVO variable as its NRVO candidate can
11374 /// use the named return value optimization.
11376 /// This function applies a very simplistic algorithm for NRVO: if every return
11377 /// statement in the scope of a variable has the same NRVO candidate, that
11378 /// candidate is an NRVO variable.
11379 void Sema::computeNRVO(Stmt *Body, FunctionScopeInfo *Scope) {
11380 ReturnStmt **Returns = Scope->Returns.data();
11382 for (unsigned I = 0, E = Scope->Returns.size(); I != E; ++I) {
11383 if (const VarDecl *NRVOCandidate = Returns[I]->getNRVOCandidate()) {
11384 if (!NRVOCandidate->isNRVOVariable())
11385 Returns[I]->setNRVOCandidate(nullptr);
11390 bool Sema::canDelayFunctionBody(const Declarator &D) {
11391 // We can't delay parsing the body of a constexpr function template (yet).
11392 if (D.getDeclSpec().isConstexprSpecified())
11395 // We can't delay parsing the body of a function template with a deduced
11396 // return type (yet).
11397 if (D.getDeclSpec().containsPlaceholderType()) {
11398 // If the placeholder introduces a non-deduced trailing return type,
11399 // we can still delay parsing it.
11400 if (D.getNumTypeObjects()) {
11401 const auto &Outer = D.getTypeObject(D.getNumTypeObjects() - 1);
11402 if (Outer.Kind == DeclaratorChunk::Function &&
11403 Outer.Fun.hasTrailingReturnType()) {
11404 QualType Ty = GetTypeFromParser(Outer.Fun.getTrailingReturnType());
11405 return Ty.isNull() || !Ty->isUndeducedType();
11414 bool Sema::canSkipFunctionBody(Decl *D) {
11415 // We cannot skip the body of a function (or function template) which is
11416 // constexpr, since we may need to evaluate its body in order to parse the
11417 // rest of the file.
11418 // We cannot skip the body of a function with an undeduced return type,
11419 // because any callers of that function need to know the type.
11420 if (const FunctionDecl *FD = D->getAsFunction())
11421 if (FD->isConstexpr() || FD->getReturnType()->isUndeducedType())
11423 return Consumer.shouldSkipFunctionBody(D);
11426 Decl *Sema::ActOnSkippedFunctionBody(Decl *Decl) {
11427 if (FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(Decl))
11428 FD->setHasSkippedBody();
11429 else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(Decl))
11430 MD->setHasSkippedBody();
11434 Decl *Sema::ActOnFinishFunctionBody(Decl *D, Stmt *BodyArg) {
11435 return ActOnFinishFunctionBody(D, BodyArg, false);
11438 Decl *Sema::ActOnFinishFunctionBody(Decl *dcl, Stmt *Body,
11439 bool IsInstantiation) {
11440 FunctionDecl *FD = dcl ? dcl->getAsFunction() : nullptr;
11442 sema::AnalysisBasedWarnings::Policy WP = AnalysisWarnings.getDefaultPolicy();
11443 sema::AnalysisBasedWarnings::Policy *ActivePolicy = nullptr;
11445 if (getLangOpts().Coroutines && !getCurFunction()->CoroutineStmts.empty())
11446 CheckCompletedCoroutineBody(FD, Body);
11451 if (getLangOpts().CPlusPlus14) {
11452 if (!FD->isInvalidDecl() && Body && !FD->isDependentContext() &&
11453 FD->getReturnType()->isUndeducedType()) {
11454 // If the function has a deduced result type but contains no 'return'
11455 // statements, the result type as written must be exactly 'auto', and
11456 // the deduced result type is 'void'.
11457 if (!FD->getReturnType()->getAs<AutoType>()) {
11458 Diag(dcl->getLocation(), diag::err_auto_fn_no_return_but_not_auto)
11459 << FD->getReturnType();
11460 FD->setInvalidDecl();
11462 // Substitute 'void' for the 'auto' in the type.
11463 TypeLoc ResultType = getReturnTypeLoc(FD);
11464 Context.adjustDeducedFunctionResultType(
11465 FD, SubstAutoType(ResultType.getType(), Context.VoidTy));
11468 } else if (getLangOpts().CPlusPlus11 && isLambdaCallOperator(FD)) {
11469 // In C++11, we don't use 'auto' deduction rules for lambda call
11470 // operators because we don't support return type deduction.
11471 auto *LSI = getCurLambda();
11472 if (LSI->HasImplicitReturnType) {
11473 deduceClosureReturnType(*LSI);
11475 // C++11 [expr.prim.lambda]p4:
11476 // [...] if there are no return statements in the compound-statement
11477 // [the deduced type is] the type void
11479 LSI->ReturnType.isNull() ? Context.VoidTy : LSI->ReturnType;
11481 // Update the return type to the deduced type.
11482 const FunctionProtoType *Proto =
11483 FD->getType()->getAs<FunctionProtoType>();
11484 FD->setType(Context.getFunctionType(RetType, Proto->getParamTypes(),
11485 Proto->getExtProtoInfo()));
11489 // The only way to be included in UndefinedButUsed is if there is an
11490 // ODR use before the definition. Avoid the expensive map lookup if this
11491 // is the first declaration.
11492 if (!FD->isFirstDecl() && FD->getPreviousDecl()->isUsed()) {
11493 if (!FD->isExternallyVisible())
11494 UndefinedButUsed.erase(FD);
11495 else if (FD->isInlined() &&
11496 !LangOpts.GNUInline &&
11497 (!FD->getPreviousDecl()->hasAttr<GNUInlineAttr>()))
11498 UndefinedButUsed.erase(FD);
11501 // If the function implicitly returns zero (like 'main') or is naked,
11502 // don't complain about missing return statements.
11503 if (FD->hasImplicitReturnZero() || FD->hasAttr<NakedAttr>())
11504 WP.disableCheckFallThrough();
11506 // MSVC permits the use of pure specifier (=0) on function definition,
11507 // defined at class scope, warn about this non-standard construct.
11508 if (getLangOpts().MicrosoftExt && FD->isPure() && FD->isCanonicalDecl())
11509 Diag(FD->getLocation(), diag::ext_pure_function_definition);
11511 if (!FD->isInvalidDecl()) {
11512 // Don't diagnose unused parameters of defaulted or deleted functions.
11513 if (!FD->isDeleted() && !FD->isDefaulted())
11514 DiagnoseUnusedParameters(FD->parameters());
11515 DiagnoseSizeOfParametersAndReturnValue(FD->parameters(),
11516 FD->getReturnType(), FD);
11518 // If this is a structor, we need a vtable.
11519 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(FD))
11520 MarkVTableUsed(FD->getLocation(), Constructor->getParent());
11521 else if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(FD))
11522 MarkVTableUsed(FD->getLocation(), Destructor->getParent());
11524 // Try to apply the named return value optimization. We have to check
11525 // if we can do this here because lambdas keep return statements around
11526 // to deduce an implicit return type.
11527 if (getLangOpts().CPlusPlus && FD->getReturnType()->isRecordType() &&
11528 !FD->isDependentContext())
11529 computeNRVO(Body, getCurFunction());
11532 // GNU warning -Wmissing-prototypes:
11533 // Warn if a global function is defined without a previous
11534 // prototype declaration. This warning is issued even if the
11535 // definition itself provides a prototype. The aim is to detect
11536 // global functions that fail to be declared in header files.
11537 const FunctionDecl *PossibleZeroParamPrototype = nullptr;
11538 if (ShouldWarnAboutMissingPrototype(FD, PossibleZeroParamPrototype)) {
11539 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD;
11541 if (PossibleZeroParamPrototype) {
11542 // We found a declaration that is not a prototype,
11543 // but that could be a zero-parameter prototype
11544 if (TypeSourceInfo *TI =
11545 PossibleZeroParamPrototype->getTypeSourceInfo()) {
11546 TypeLoc TL = TI->getTypeLoc();
11547 if (FunctionNoProtoTypeLoc FTL = TL.getAs<FunctionNoProtoTypeLoc>())
11548 Diag(PossibleZeroParamPrototype->getLocation(),
11549 diag::note_declaration_not_a_prototype)
11550 << PossibleZeroParamPrototype
11551 << FixItHint::CreateInsertion(FTL.getRParenLoc(), "void");
11556 if (auto *MD = dyn_cast<CXXMethodDecl>(FD)) {
11557 const CXXMethodDecl *KeyFunction;
11558 if (MD->isOutOfLine() && (MD = MD->getCanonicalDecl()) &&
11560 (KeyFunction = Context.getCurrentKeyFunction(MD->getParent())) &&
11561 MD == KeyFunction->getCanonicalDecl()) {
11562 // Update the key-function state if necessary for this ABI.
11563 if (FD->isInlined() &&
11564 !Context.getTargetInfo().getCXXABI().canKeyFunctionBeInline()) {
11565 Context.setNonKeyFunction(MD);
11567 // If the newly-chosen key function is already defined, then we
11568 // need to mark the vtable as used retroactively.
11569 KeyFunction = Context.getCurrentKeyFunction(MD->getParent());
11570 const FunctionDecl *Definition;
11571 if (KeyFunction && KeyFunction->isDefined(Definition))
11572 MarkVTableUsed(Definition->getLocation(), MD->getParent(), true);
11574 // We just defined they key function; mark the vtable as used.
11575 MarkVTableUsed(FD->getLocation(), MD->getParent(), true);
11580 assert((FD == getCurFunctionDecl() || getCurLambda()->CallOperator == FD) &&
11581 "Function parsing confused");
11582 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) {
11583 assert(MD == getCurMethodDecl() && "Method parsing confused");
11585 if (!MD->isInvalidDecl()) {
11586 DiagnoseUnusedParameters(MD->parameters());
11587 DiagnoseSizeOfParametersAndReturnValue(MD->parameters(),
11588 MD->getReturnType(), MD);
11591 computeNRVO(Body, getCurFunction());
11593 if (getCurFunction()->ObjCShouldCallSuper) {
11594 Diag(MD->getLocEnd(), diag::warn_objc_missing_super_call)
11595 << MD->getSelector().getAsString();
11596 getCurFunction()->ObjCShouldCallSuper = false;
11598 if (getCurFunction()->ObjCWarnForNoDesignatedInitChain) {
11599 const ObjCMethodDecl *InitMethod = nullptr;
11600 bool isDesignated =
11601 MD->isDesignatedInitializerForTheInterface(&InitMethod);
11602 assert(isDesignated && InitMethod);
11603 (void)isDesignated;
11605 auto superIsNSObject = [&](const ObjCMethodDecl *MD) {
11606 auto IFace = MD->getClassInterface();
11609 auto SuperD = IFace->getSuperClass();
11612 return SuperD->getIdentifier() ==
11613 NSAPIObj->getNSClassId(NSAPI::ClassId_NSObject);
11615 // Don't issue this warning for unavailable inits or direct subclasses
11617 if (!MD->isUnavailable() && !superIsNSObject(MD)) {
11618 Diag(MD->getLocation(),
11619 diag::warn_objc_designated_init_missing_super_call);
11620 Diag(InitMethod->getLocation(),
11621 diag::note_objc_designated_init_marked_here);
11623 getCurFunction()->ObjCWarnForNoDesignatedInitChain = false;
11625 if (getCurFunction()->ObjCWarnForNoInitDelegation) {
11626 // Don't issue this warning for unavaialable inits.
11627 if (!MD->isUnavailable())
11628 Diag(MD->getLocation(),
11629 diag::warn_objc_secondary_init_missing_init_call);
11630 getCurFunction()->ObjCWarnForNoInitDelegation = false;
11636 assert(!getCurFunction()->ObjCShouldCallSuper &&
11637 "This should only be set for ObjC methods, which should have been "
11638 "handled in the block above.");
11640 // Verify and clean out per-function state.
11641 if (Body && (!FD || !FD->isDefaulted())) {
11642 // C++ constructors that have function-try-blocks can't have return
11643 // statements in the handlers of that block. (C++ [except.handle]p14)
11645 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body))
11646 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body));
11648 // Verify that gotos and switch cases don't jump into scopes illegally.
11649 if (getCurFunction()->NeedsScopeChecking() &&
11650 !PP.isCodeCompletionEnabled())
11651 DiagnoseInvalidJumps(Body);
11653 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) {
11654 if (!Destructor->getParent()->isDependentType())
11655 CheckDestructor(Destructor);
11657 MarkBaseAndMemberDestructorsReferenced(Destructor->getLocation(),
11658 Destructor->getParent());
11661 // If any errors have occurred, clear out any temporaries that may have
11662 // been leftover. This ensures that these temporaries won't be picked up for
11663 // deletion in some later function.
11664 if (getDiagnostics().hasErrorOccurred() ||
11665 getDiagnostics().getSuppressAllDiagnostics()) {
11666 DiscardCleanupsInEvaluationContext();
11668 if (!getDiagnostics().hasUncompilableErrorOccurred() &&
11669 !isa<FunctionTemplateDecl>(dcl)) {
11670 // Since the body is valid, issue any analysis-based warnings that are
11672 ActivePolicy = &WP;
11675 if (!IsInstantiation && FD && FD->isConstexpr() && !FD->isInvalidDecl() &&
11676 (!CheckConstexprFunctionDecl(FD) ||
11677 !CheckConstexprFunctionBody(FD, Body)))
11678 FD->setInvalidDecl();
11680 if (FD && FD->hasAttr<NakedAttr>()) {
11681 for (const Stmt *S : Body->children()) {
11682 if (!isa<AsmStmt>(S) && !isa<NullStmt>(S)) {
11683 Diag(S->getLocStart(), diag::err_non_asm_stmt_in_naked_function);
11684 Diag(FD->getAttr<NakedAttr>()->getLocation(), diag::note_attribute);
11685 FD->setInvalidDecl();
11691 assert(ExprCleanupObjects.size() ==
11692 ExprEvalContexts.back().NumCleanupObjects &&
11693 "Leftover temporaries in function");
11694 assert(!Cleanup.exprNeedsCleanups() && "Unaccounted cleanups in function");
11695 assert(MaybeODRUseExprs.empty() &&
11696 "Leftover expressions for odr-use checking");
11699 if (!IsInstantiation)
11702 PopFunctionScopeInfo(ActivePolicy, dcl);
11703 // If any errors have occurred, clear out any temporaries that may have
11704 // been leftover. This ensures that these temporaries won't be picked up for
11705 // deletion in some later function.
11706 if (getDiagnostics().hasErrorOccurred()) {
11707 DiscardCleanupsInEvaluationContext();
11713 /// When we finish delayed parsing of an attribute, we must attach it to the
11715 void Sema::ActOnFinishDelayedAttribute(Scope *S, Decl *D,
11716 ParsedAttributes &Attrs) {
11717 // Always attach attributes to the underlying decl.
11718 if (TemplateDecl *TD = dyn_cast<TemplateDecl>(D))
11719 D = TD->getTemplatedDecl();
11720 ProcessDeclAttributeList(S, D, Attrs.getList());
11722 if (CXXMethodDecl *Method = dyn_cast_or_null<CXXMethodDecl>(D))
11723 if (Method->isStatic())
11724 checkThisInStaticMemberFunctionAttributes(Method);
11727 /// ImplicitlyDefineFunction - An undeclared identifier was used in a function
11728 /// call, forming a call to an implicitly defined function (per C99 6.5.1p2).
11729 NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc,
11730 IdentifierInfo &II, Scope *S) {
11731 // Before we produce a declaration for an implicitly defined
11732 // function, see whether there was a locally-scoped declaration of
11733 // this name as a function or variable. If so, use that
11734 // (non-visible) declaration, and complain about it.
11735 if (NamedDecl *ExternCPrev = findLocallyScopedExternCDecl(&II)) {
11736 Diag(Loc, diag::warn_use_out_of_scope_declaration) << ExternCPrev;
11737 Diag(ExternCPrev->getLocation(), diag::note_previous_declaration);
11738 return ExternCPrev;
11741 // Extension in C99. Legal in C90, but warn about it.
11743 if (II.getName().startswith("__builtin_"))
11744 diag_id = diag::warn_builtin_unknown;
11745 else if (getLangOpts().C99)
11746 diag_id = diag::ext_implicit_function_decl;
11748 diag_id = diag::warn_implicit_function_decl;
11749 Diag(Loc, diag_id) << &II;
11751 // Because typo correction is expensive, only do it if the implicit
11752 // function declaration is going to be treated as an error.
11753 if (Diags.getDiagnosticLevel(diag_id, Loc) >= DiagnosticsEngine::Error) {
11754 TypoCorrection Corrected;
11756 (Corrected = CorrectTypo(
11757 DeclarationNameInfo(&II, Loc), LookupOrdinaryName, S, nullptr,
11758 llvm::make_unique<DeclFilterCCC<FunctionDecl>>(), CTK_NonError)))
11759 diagnoseTypo(Corrected, PDiag(diag::note_function_suggestion),
11760 /*ErrorRecovery*/false);
11763 // Set a Declarator for the implicit definition: int foo();
11765 AttributeFactory attrFactory;
11766 DeclSpec DS(attrFactory);
11768 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID,
11769 Context.getPrintingPolicy());
11770 (void)Error; // Silence warning.
11771 assert(!Error && "Error setting up implicit decl!");
11772 SourceLocation NoLoc;
11773 Declarator D(DS, Declarator::BlockContext);
11774 D.AddTypeInfo(DeclaratorChunk::getFunction(/*HasProto=*/false,
11775 /*IsAmbiguous=*/false,
11776 /*LParenLoc=*/NoLoc,
11777 /*Params=*/nullptr,
11779 /*EllipsisLoc=*/NoLoc,
11780 /*RParenLoc=*/NoLoc,
11782 /*RefQualifierIsLvalueRef=*/true,
11783 /*RefQualifierLoc=*/NoLoc,
11784 /*ConstQualifierLoc=*/NoLoc,
11785 /*VolatileQualifierLoc=*/NoLoc,
11786 /*RestrictQualifierLoc=*/NoLoc,
11787 /*MutableLoc=*/NoLoc,
11789 /*ESpecRange=*/SourceRange(),
11790 /*Exceptions=*/nullptr,
11791 /*ExceptionRanges=*/nullptr,
11792 /*NumExceptions=*/0,
11793 /*NoexceptExpr=*/nullptr,
11794 /*ExceptionSpecTokens=*/nullptr,
11796 DS.getAttributes(),
11798 D.SetIdentifier(&II, Loc);
11800 // Insert this function into translation-unit scope.
11802 DeclContext *PrevDC = CurContext;
11803 CurContext = Context.getTranslationUnitDecl();
11805 FunctionDecl *FD = cast<FunctionDecl>(ActOnDeclarator(TUScope, D));
11808 CurContext = PrevDC;
11810 AddKnownFunctionAttributes(FD);
11815 /// \brief Adds any function attributes that we know a priori based on
11816 /// the declaration of this function.
11818 /// These attributes can apply both to implicitly-declared builtins
11819 /// (like __builtin___printf_chk) or to library-declared functions
11820 /// like NSLog or printf.
11822 /// We need to check for duplicate attributes both here and where user-written
11823 /// attributes are applied to declarations.
11824 void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) {
11825 if (FD->isInvalidDecl())
11828 // If this is a built-in function, map its builtin attributes to
11829 // actual attributes.
11830 if (unsigned BuiltinID = FD->getBuiltinID()) {
11831 // Handle printf-formatting attributes.
11832 unsigned FormatIdx;
11834 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) {
11835 if (!FD->hasAttr<FormatAttr>()) {
11836 const char *fmt = "printf";
11837 unsigned int NumParams = FD->getNumParams();
11838 if (FormatIdx < NumParams && // NumParams may be 0 (e.g. vfprintf)
11839 FD->getParamDecl(FormatIdx)->getType()->isObjCObjectPointerType())
11841 FD->addAttr(FormatAttr::CreateImplicit(Context,
11842 &Context.Idents.get(fmt),
11844 HasVAListArg ? 0 : FormatIdx+2,
11845 FD->getLocation()));
11848 if (Context.BuiltinInfo.isScanfLike(BuiltinID, FormatIdx,
11850 if (!FD->hasAttr<FormatAttr>())
11851 FD->addAttr(FormatAttr::CreateImplicit(Context,
11852 &Context.Idents.get("scanf"),
11854 HasVAListArg ? 0 : FormatIdx+2,
11855 FD->getLocation()));
11858 // Mark const if we don't care about errno and that is the only
11859 // thing preventing the function from being const. This allows
11860 // IRgen to use LLVM intrinsics for such functions.
11861 if (!getLangOpts().MathErrno &&
11862 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) {
11863 if (!FD->hasAttr<ConstAttr>())
11864 FD->addAttr(ConstAttr::CreateImplicit(Context, FD->getLocation()));
11867 if (Context.BuiltinInfo.isReturnsTwice(BuiltinID) &&
11868 !FD->hasAttr<ReturnsTwiceAttr>())
11869 FD->addAttr(ReturnsTwiceAttr::CreateImplicit(Context,
11870 FD->getLocation()));
11871 if (Context.BuiltinInfo.isNoThrow(BuiltinID) && !FD->hasAttr<NoThrowAttr>())
11872 FD->addAttr(NoThrowAttr::CreateImplicit(Context, FD->getLocation()));
11873 if (Context.BuiltinInfo.isPure(BuiltinID) && !FD->hasAttr<PureAttr>())
11874 FD->addAttr(PureAttr::CreateImplicit(Context, FD->getLocation()));
11875 if (Context.BuiltinInfo.isConst(BuiltinID) && !FD->hasAttr<ConstAttr>())
11876 FD->addAttr(ConstAttr::CreateImplicit(Context, FD->getLocation()));
11877 if (getLangOpts().CUDA && Context.BuiltinInfo.isTSBuiltin(BuiltinID) &&
11878 !FD->hasAttr<CUDADeviceAttr>() && !FD->hasAttr<CUDAHostAttr>()) {
11879 // Add the appropriate attribute, depending on the CUDA compilation mode
11880 // and which target the builtin belongs to. For example, during host
11881 // compilation, aux builtins are __device__, while the rest are __host__.
11882 if (getLangOpts().CUDAIsDevice !=
11883 Context.BuiltinInfo.isAuxBuiltinID(BuiltinID))
11884 FD->addAttr(CUDADeviceAttr::CreateImplicit(Context, FD->getLocation()));
11886 FD->addAttr(CUDAHostAttr::CreateImplicit(Context, FD->getLocation()));
11890 // If C++ exceptions are enabled but we are told extern "C" functions cannot
11891 // throw, add an implicit nothrow attribute to any extern "C" function we come
11893 if (getLangOpts().CXXExceptions && getLangOpts().ExternCNoUnwind &&
11894 FD->isExternC() && !FD->hasAttr<NoThrowAttr>()) {
11895 const auto *FPT = FD->getType()->getAs<FunctionProtoType>();
11896 if (!FPT || FPT->getExceptionSpecType() == EST_None)
11897 FD->addAttr(NoThrowAttr::CreateImplicit(Context, FD->getLocation()));
11900 IdentifierInfo *Name = FD->getIdentifier();
11903 if ((!getLangOpts().CPlusPlus &&
11904 FD->getDeclContext()->isTranslationUnit()) ||
11905 (isa<LinkageSpecDecl>(FD->getDeclContext()) &&
11906 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() ==
11907 LinkageSpecDecl::lang_c)) {
11908 // Okay: this could be a libc/libm/Objective-C function we know
11913 if (Name->isStr("asprintf") || Name->isStr("vasprintf")) {
11914 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be
11915 // target-specific builtins, perhaps?
11916 if (!FD->hasAttr<FormatAttr>())
11917 FD->addAttr(FormatAttr::CreateImplicit(Context,
11918 &Context.Idents.get("printf"), 2,
11919 Name->isStr("vasprintf") ? 0 : 3,
11920 FD->getLocation()));
11923 if (Name->isStr("__CFStringMakeConstantString")) {
11924 // We already have a __builtin___CFStringMakeConstantString,
11925 // but builds that use -fno-constant-cfstrings don't go through that.
11926 if (!FD->hasAttr<FormatArgAttr>())
11927 FD->addAttr(FormatArgAttr::CreateImplicit(Context, 1,
11928 FD->getLocation()));
11932 TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T,
11933 TypeSourceInfo *TInfo) {
11934 assert(D.getIdentifier() && "Wrong callback for declspec without declarator");
11935 assert(!T.isNull() && "GetTypeForDeclarator() returned null type");
11938 assert(D.isInvalidType() && "no declarator info for valid type");
11939 TInfo = Context.getTrivialTypeSourceInfo(T);
11942 // Scope manipulation handled by caller.
11943 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext,
11945 D.getIdentifierLoc(),
11949 // Bail out immediately if we have an invalid declaration.
11950 if (D.isInvalidType()) {
11951 NewTD->setInvalidDecl();
11955 if (D.getDeclSpec().isModulePrivateSpecified()) {
11956 if (CurContext->isFunctionOrMethod())
11957 Diag(NewTD->getLocation(), diag::err_module_private_local)
11958 << 2 << NewTD->getDeclName()
11959 << SourceRange(D.getDeclSpec().getModulePrivateSpecLoc())
11960 << FixItHint::CreateRemoval(D.getDeclSpec().getModulePrivateSpecLoc());
11962 NewTD->setModulePrivate();
11965 // C++ [dcl.typedef]p8:
11966 // If the typedef declaration defines an unnamed class (or
11967 // enum), the first typedef-name declared by the declaration
11968 // to be that class type (or enum type) is used to denote the
11969 // class type (or enum type) for linkage purposes only.
11970 // We need to check whether the type was declared in the declaration.
11971 switch (D.getDeclSpec().getTypeSpecType()) {
11974 case TST_interface:
11977 TagDecl *tagFromDeclSpec = cast<TagDecl>(D.getDeclSpec().getRepAsDecl());
11978 setTagNameForLinkagePurposes(tagFromDeclSpec, NewTD);
11989 /// \brief Check that this is a valid underlying type for an enum declaration.
11990 bool Sema::CheckEnumUnderlyingType(TypeSourceInfo *TI) {
11991 SourceLocation UnderlyingLoc = TI->getTypeLoc().getBeginLoc();
11992 QualType T = TI->getType();
11994 if (T->isDependentType())
11997 if (const BuiltinType *BT = T->getAs<BuiltinType>())
11998 if (BT->isInteger())
12001 Diag(UnderlyingLoc, diag::err_enum_invalid_underlying) << T;
12005 /// Check whether this is a valid redeclaration of a previous enumeration.
12006 /// \return true if the redeclaration was invalid.
12007 bool Sema::CheckEnumRedeclaration(
12008 SourceLocation EnumLoc, bool IsScoped, QualType EnumUnderlyingTy,
12009 bool EnumUnderlyingIsImplicit, const EnumDecl *Prev) {
12010 bool IsFixed = !EnumUnderlyingTy.isNull();
12012 if (IsScoped != Prev->isScoped()) {
12013 Diag(EnumLoc, diag::err_enum_redeclare_scoped_mismatch)
12014 << Prev->isScoped();
12015 Diag(Prev->getLocation(), diag::note_previous_declaration);
12019 if (IsFixed && Prev->isFixed()) {
12020 if (!EnumUnderlyingTy->isDependentType() &&
12021 !Prev->getIntegerType()->isDependentType() &&
12022 !Context.hasSameUnqualifiedType(EnumUnderlyingTy,
12023 Prev->getIntegerType())) {
12024 // TODO: Highlight the underlying type of the redeclaration.
12025 Diag(EnumLoc, diag::err_enum_redeclare_type_mismatch)
12026 << EnumUnderlyingTy << Prev->getIntegerType();
12027 Diag(Prev->getLocation(), diag::note_previous_declaration)
12028 << Prev->getIntegerTypeRange();
12031 } else if (IsFixed && !Prev->isFixed() && EnumUnderlyingIsImplicit) {
12033 } else if (!IsFixed && Prev->isFixed() && !Prev->getIntegerTypeSourceInfo()) {
12035 } else if (IsFixed != Prev->isFixed()) {
12036 Diag(EnumLoc, diag::err_enum_redeclare_fixed_mismatch)
12037 << Prev->isFixed();
12038 Diag(Prev->getLocation(), diag::note_previous_declaration);
12045 /// \brief Get diagnostic %select index for tag kind for
12046 /// redeclaration diagnostic message.
12047 /// WARNING: Indexes apply to particular diagnostics only!
12049 /// \returns diagnostic %select index.
12050 static unsigned getRedeclDiagFromTagKind(TagTypeKind Tag) {
12052 case TTK_Struct: return 0;
12053 case TTK_Interface: return 1;
12054 case TTK_Class: return 2;
12055 default: llvm_unreachable("Invalid tag kind for redecl diagnostic!");
12059 /// \brief Determine if tag kind is a class-key compatible with
12060 /// class for redeclaration (class, struct, or __interface).
12062 /// \returns true iff the tag kind is compatible.
12063 static bool isClassCompatTagKind(TagTypeKind Tag)
12065 return Tag == TTK_Struct || Tag == TTK_Class || Tag == TTK_Interface;
12068 /// \brief Determine whether a tag with a given kind is acceptable
12069 /// as a redeclaration of the given tag declaration.
12071 /// \returns true if the new tag kind is acceptable, false otherwise.
12072 bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous,
12073 TagTypeKind NewTag, bool isDefinition,
12074 SourceLocation NewTagLoc,
12075 const IdentifierInfo *Name) {
12076 // C++ [dcl.type.elab]p3:
12077 // The class-key or enum keyword present in the
12078 // elaborated-type-specifier shall agree in kind with the
12079 // declaration to which the name in the elaborated-type-specifier
12080 // refers. This rule also applies to the form of
12081 // elaborated-type-specifier that declares a class-name or
12082 // friend class since it can be construed as referring to the
12083 // definition of the class. Thus, in any
12084 // elaborated-type-specifier, the enum keyword shall be used to
12085 // refer to an enumeration (7.2), the union class-key shall be
12086 // used to refer to a union (clause 9), and either the class or
12087 // struct class-key shall be used to refer to a class (clause 9)
12088 // declared using the class or struct class-key.
12089 TagTypeKind OldTag = Previous->getTagKind();
12090 if (!isDefinition || !isClassCompatTagKind(NewTag))
12091 if (OldTag == NewTag)
12094 if (isClassCompatTagKind(OldTag) && isClassCompatTagKind(NewTag)) {
12095 // Warn about the struct/class tag mismatch.
12096 bool isTemplate = false;
12097 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous))
12098 isTemplate = Record->getDescribedClassTemplate();
12100 if (!ActiveTemplateInstantiations.empty()) {
12101 // In a template instantiation, do not offer fix-its for tag mismatches
12102 // since they usually mess up the template instead of fixing the problem.
12103 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch)
12104 << getRedeclDiagFromTagKind(NewTag) << isTemplate << Name
12105 << getRedeclDiagFromTagKind(OldTag);
12109 if (isDefinition) {
12110 // On definitions, check previous tags and issue a fix-it for each
12111 // one that doesn't match the current tag.
12112 if (Previous->getDefinition()) {
12113 // Don't suggest fix-its for redefinitions.
12117 bool previousMismatch = false;
12118 for (auto I : Previous->redecls()) {
12119 if (I->getTagKind() != NewTag) {
12120 if (!previousMismatch) {
12121 previousMismatch = true;
12122 Diag(NewTagLoc, diag::warn_struct_class_previous_tag_mismatch)
12123 << getRedeclDiagFromTagKind(NewTag) << isTemplate << Name
12124 << getRedeclDiagFromTagKind(I->getTagKind());
12126 Diag(I->getInnerLocStart(), diag::note_struct_class_suggestion)
12127 << getRedeclDiagFromTagKind(NewTag)
12128 << FixItHint::CreateReplacement(I->getInnerLocStart(),
12129 TypeWithKeyword::getTagTypeKindName(NewTag));
12135 // Check for a previous definition. If current tag and definition
12136 // are same type, do nothing. If no definition, but disagree with
12137 // with previous tag type, give a warning, but no fix-it.
12138 const TagDecl *Redecl = Previous->getDefinition() ?
12139 Previous->getDefinition() : Previous;
12140 if (Redecl->getTagKind() == NewTag) {
12144 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch)
12145 << getRedeclDiagFromTagKind(NewTag) << isTemplate << Name
12146 << getRedeclDiagFromTagKind(OldTag);
12147 Diag(Redecl->getLocation(), diag::note_previous_use);
12149 // If there is a previous definition, suggest a fix-it.
12150 if (Previous->getDefinition()) {
12151 Diag(NewTagLoc, diag::note_struct_class_suggestion)
12152 << getRedeclDiagFromTagKind(Redecl->getTagKind())
12153 << FixItHint::CreateReplacement(SourceRange(NewTagLoc),
12154 TypeWithKeyword::getTagTypeKindName(Redecl->getTagKind()));
12162 /// Add a minimal nested name specifier fixit hint to allow lookup of a tag name
12163 /// from an outer enclosing namespace or file scope inside a friend declaration.
12164 /// This should provide the commented out code in the following snippet:
12168 /// struct Y { friend struct /*N::*/ X; };
12171 static FixItHint createFriendTagNNSFixIt(Sema &SemaRef, NamedDecl *ND, Scope *S,
12172 SourceLocation NameLoc) {
12173 // While the decl is in a namespace, do repeated lookup of that name and see
12174 // if we get the same namespace back. If we do not, continue until
12175 // translation unit scope, at which point we have a fully qualified NNS.
12176 SmallVector<IdentifierInfo *, 4> Namespaces;
12177 DeclContext *DC = ND->getDeclContext()->getRedeclContext();
12178 for (; !DC->isTranslationUnit(); DC = DC->getParent()) {
12179 // This tag should be declared in a namespace, which can only be enclosed by
12180 // other namespaces. Bail if there's an anonymous namespace in the chain.
12181 NamespaceDecl *Namespace = dyn_cast<NamespaceDecl>(DC);
12182 if (!Namespace || Namespace->isAnonymousNamespace())
12183 return FixItHint();
12184 IdentifierInfo *II = Namespace->getIdentifier();
12185 Namespaces.push_back(II);
12186 NamedDecl *Lookup = SemaRef.LookupSingleName(
12187 S, II, NameLoc, Sema::LookupNestedNameSpecifierName);
12188 if (Lookup == Namespace)
12192 // Once we have all the namespaces, reverse them to go outermost first, and
12194 SmallString<64> Insertion;
12195 llvm::raw_svector_ostream OS(Insertion);
12196 if (DC->isTranslationUnit())
12198 std::reverse(Namespaces.begin(), Namespaces.end());
12199 for (auto *II : Namespaces)
12200 OS << II->getName() << "::";
12201 return FixItHint::CreateInsertion(NameLoc, Insertion);
12204 /// \brief Determine whether a tag originally declared in context \p OldDC can
12205 /// be redeclared with an unqualfied name in \p NewDC (assuming name lookup
12206 /// found a declaration in \p OldDC as a previous decl, perhaps through a
12207 /// using-declaration).
12208 static bool isAcceptableTagRedeclContext(Sema &S, DeclContext *OldDC,
12209 DeclContext *NewDC) {
12210 OldDC = OldDC->getRedeclContext();
12211 NewDC = NewDC->getRedeclContext();
12213 if (OldDC->Equals(NewDC))
12216 // In MSVC mode, we allow a redeclaration if the contexts are related (either
12217 // encloses the other).
12218 if (S.getLangOpts().MSVCCompat &&
12219 (OldDC->Encloses(NewDC) || NewDC->Encloses(OldDC)))
12225 /// Find the DeclContext in which a tag is implicitly declared if we see an
12226 /// elaborated type specifier in the specified context, and lookup finds
12228 static DeclContext *getTagInjectionContext(DeclContext *DC) {
12229 while (!DC->isFileContext() && !DC->isFunctionOrMethod())
12230 DC = DC->getParent();
12234 /// Find the Scope in which a tag is implicitly declared if we see an
12235 /// elaborated type specifier in the specified context, and lookup finds
12237 static Scope *getTagInjectionScope(Scope *S, const LangOptions &LangOpts) {
12238 while (S->isClassScope() ||
12239 (LangOpts.CPlusPlus &&
12240 S->isFunctionPrototypeScope()) ||
12241 ((S->getFlags() & Scope::DeclScope) == 0) ||
12242 (S->getEntity() && S->getEntity()->isTransparentContext()))
12243 S = S->getParent();
12247 /// \brief This is invoked when we see 'struct foo' or 'struct {'. In the
12248 /// former case, Name will be non-null. In the later case, Name will be null.
12249 /// TagSpec indicates what kind of tag this is. TUK indicates whether this is a
12250 /// reference/declaration/definition of a tag.
12252 /// \param IsTypeSpecifier \c true if this is a type-specifier (or
12253 /// trailing-type-specifier) other than one in an alias-declaration.
12255 /// \param SkipBody If non-null, will be set to indicate if the caller should
12256 /// skip the definition of this tag and treat it as if it were a declaration.
12257 Decl *Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK,
12258 SourceLocation KWLoc, CXXScopeSpec &SS,
12259 IdentifierInfo *Name, SourceLocation NameLoc,
12260 AttributeList *Attr, AccessSpecifier AS,
12261 SourceLocation ModulePrivateLoc,
12262 MultiTemplateParamsArg TemplateParameterLists,
12263 bool &OwnedDecl, bool &IsDependent,
12264 SourceLocation ScopedEnumKWLoc,
12265 bool ScopedEnumUsesClassTag,
12266 TypeResult UnderlyingType,
12267 bool IsTypeSpecifier, SkipBodyInfo *SkipBody) {
12268 // If this is not a definition, it must have a name.
12269 IdentifierInfo *OrigName = Name;
12270 assert((Name != nullptr || TUK == TUK_Definition) &&
12271 "Nameless record must be a definition!");
12272 assert(TemplateParameterLists.size() == 0 || TUK != TUK_Reference);
12275 TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec);
12276 bool ScopedEnum = ScopedEnumKWLoc.isValid();
12278 // FIXME: Check explicit specializations more carefully.
12279 bool isExplicitSpecialization = false;
12280 bool Invalid = false;
12282 // We only need to do this matching if we have template parameters
12283 // or a scope specifier, which also conveniently avoids this work
12284 // for non-C++ cases.
12285 if (TemplateParameterLists.size() > 0 ||
12286 (SS.isNotEmpty() && TUK != TUK_Reference)) {
12287 if (TemplateParameterList *TemplateParams =
12288 MatchTemplateParametersToScopeSpecifier(
12289 KWLoc, NameLoc, SS, nullptr, TemplateParameterLists,
12290 TUK == TUK_Friend, isExplicitSpecialization, Invalid)) {
12291 if (Kind == TTK_Enum) {
12292 Diag(KWLoc, diag::err_enum_template);
12296 if (TemplateParams->size() > 0) {
12297 // This is a declaration or definition of a class template (which may
12298 // be a member of another template).
12304 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc,
12305 SS, Name, NameLoc, Attr,
12306 TemplateParams, AS,
12308 /*FriendLoc*/SourceLocation(),
12309 TemplateParameterLists.size()-1,
12310 TemplateParameterLists.data(),
12312 return Result.get();
12314 // The "template<>" header is extraneous.
12315 Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams)
12316 << TypeWithKeyword::getTagTypeKindName(Kind) << Name;
12317 isExplicitSpecialization = true;
12322 // Figure out the underlying type if this a enum declaration. We need to do
12323 // this early, because it's needed to detect if this is an incompatible
12325 llvm::PointerUnion<const Type*, TypeSourceInfo*> EnumUnderlying;
12326 bool EnumUnderlyingIsImplicit = false;
12328 if (Kind == TTK_Enum) {
12329 if (UnderlyingType.isInvalid() || (!UnderlyingType.get() && ScopedEnum))
12330 // No underlying type explicitly specified, or we failed to parse the
12331 // type, default to int.
12332 EnumUnderlying = Context.IntTy.getTypePtr();
12333 else if (UnderlyingType.get()) {
12334 // C++0x 7.2p2: The type-specifier-seq of an enum-base shall name an
12335 // integral type; any cv-qualification is ignored.
12336 TypeSourceInfo *TI = nullptr;
12337 GetTypeFromParser(UnderlyingType.get(), &TI);
12338 EnumUnderlying = TI;
12340 if (CheckEnumUnderlyingType(TI))
12341 // Recover by falling back to int.
12342 EnumUnderlying = Context.IntTy.getTypePtr();
12344 if (DiagnoseUnexpandedParameterPack(TI->getTypeLoc().getBeginLoc(), TI,
12345 UPPC_FixedUnderlyingType))
12346 EnumUnderlying = Context.IntTy.getTypePtr();
12348 } else if (Context.getTargetInfo().getCXXABI().isMicrosoft()) {
12349 if (getLangOpts().MSVCCompat || TUK == TUK_Definition) {
12350 // Microsoft enums are always of int type.
12351 EnumUnderlying = Context.IntTy.getTypePtr();
12352 EnumUnderlyingIsImplicit = true;
12357 DeclContext *SearchDC = CurContext;
12358 DeclContext *DC = CurContext;
12359 bool isStdBadAlloc = false;
12361 RedeclarationKind Redecl = ForRedeclaration;
12362 if (TUK == TUK_Friend || TUK == TUK_Reference)
12363 Redecl = NotForRedeclaration;
12365 LookupResult Previous(*this, Name, NameLoc, LookupTagName, Redecl);
12366 if (Name && SS.isNotEmpty()) {
12367 // We have a nested-name tag ('struct foo::bar').
12369 // Check for invalid 'foo::'.
12370 if (SS.isInvalid()) {
12372 goto CreateNewDecl;
12375 // If this is a friend or a reference to a class in a dependent
12376 // context, don't try to make a decl for it.
12377 if (TUK == TUK_Friend || TUK == TUK_Reference) {
12378 DC = computeDeclContext(SS, false);
12380 IsDependent = true;
12384 DC = computeDeclContext(SS, true);
12386 Diag(SS.getRange().getBegin(), diag::err_dependent_nested_name_spec)
12392 if (RequireCompleteDeclContext(SS, DC))
12396 // Look-up name inside 'foo::'.
12397 LookupQualifiedName(Previous, DC);
12399 if (Previous.isAmbiguous())
12402 if (Previous.empty()) {
12403 // Name lookup did not find anything. However, if the
12404 // nested-name-specifier refers to the current instantiation,
12405 // and that current instantiation has any dependent base
12406 // classes, we might find something at instantiation time: treat
12407 // this as a dependent elaborated-type-specifier.
12408 // But this only makes any sense for reference-like lookups.
12409 if (Previous.wasNotFoundInCurrentInstantiation() &&
12410 (TUK == TUK_Reference || TUK == TUK_Friend)) {
12411 IsDependent = true;
12415 // A tag 'foo::bar' must already exist.
12416 Diag(NameLoc, diag::err_not_tag_in_scope)
12417 << Kind << Name << DC << SS.getRange();
12420 goto CreateNewDecl;
12423 // C++14 [class.mem]p14:
12424 // If T is the name of a class, then each of the following shall have a
12425 // name different from T:
12426 // -- every member of class T that is itself a type
12427 if (TUK != TUK_Reference && TUK != TUK_Friend &&
12428 DiagnoseClassNameShadow(SearchDC, DeclarationNameInfo(Name, NameLoc)))
12431 // If this is a named struct, check to see if there was a previous forward
12432 // declaration or definition.
12433 // FIXME: We're looking into outer scopes here, even when we
12434 // shouldn't be. Doing so can result in ambiguities that we
12435 // shouldn't be diagnosing.
12436 LookupName(Previous, S);
12438 // When declaring or defining a tag, ignore ambiguities introduced
12439 // by types using'ed into this scope.
12440 if (Previous.isAmbiguous() &&
12441 (TUK == TUK_Definition || TUK == TUK_Declaration)) {
12442 LookupResult::Filter F = Previous.makeFilter();
12443 while (F.hasNext()) {
12444 NamedDecl *ND = F.next();
12445 if (!ND->getDeclContext()->getRedeclContext()->Equals(
12446 SearchDC->getRedeclContext()))
12452 // C++11 [namespace.memdef]p3:
12453 // If the name in a friend declaration is neither qualified nor
12454 // a template-id and the declaration is a function or an
12455 // elaborated-type-specifier, the lookup to determine whether
12456 // the entity has been previously declared shall not consider
12457 // any scopes outside the innermost enclosing namespace.
12459 // MSVC doesn't implement the above rule for types, so a friend tag
12460 // declaration may be a redeclaration of a type declared in an enclosing
12461 // scope. They do implement this rule for friend functions.
12463 // Does it matter that this should be by scope instead of by
12464 // semantic context?
12465 if (!Previous.empty() && TUK == TUK_Friend) {
12466 DeclContext *EnclosingNS = SearchDC->getEnclosingNamespaceContext();
12467 LookupResult::Filter F = Previous.makeFilter();
12468 bool FriendSawTagOutsideEnclosingNamespace = false;
12469 while (F.hasNext()) {
12470 NamedDecl *ND = F.next();
12471 DeclContext *DC = ND->getDeclContext()->getRedeclContext();
12472 if (DC->isFileContext() &&
12473 !EnclosingNS->Encloses(ND->getDeclContext())) {
12474 if (getLangOpts().MSVCCompat)
12475 FriendSawTagOutsideEnclosingNamespace = true;
12482 // Diagnose this MSVC extension in the easy case where lookup would have
12483 // unambiguously found something outside the enclosing namespace.
12484 if (Previous.isSingleResult() && FriendSawTagOutsideEnclosingNamespace) {
12485 NamedDecl *ND = Previous.getFoundDecl();
12486 Diag(NameLoc, diag::ext_friend_tag_redecl_outside_namespace)
12487 << createFriendTagNNSFixIt(*this, ND, S, NameLoc);
12491 // Note: there used to be some attempt at recovery here.
12492 if (Previous.isAmbiguous())
12495 if (!getLangOpts().CPlusPlus && TUK != TUK_Reference) {
12496 // FIXME: This makes sure that we ignore the contexts associated
12497 // with C structs, unions, and enums when looking for a matching
12498 // tag declaration or definition. See the similar lookup tweak
12499 // in Sema::LookupName; is there a better way to deal with this?
12500 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC))
12501 SearchDC = SearchDC->getParent();
12505 if (Previous.isSingleResult() &&
12506 Previous.getFoundDecl()->isTemplateParameter()) {
12507 // Maybe we will complain about the shadowed template parameter.
12508 DiagnoseTemplateParameterShadow(NameLoc, Previous.getFoundDecl());
12509 // Just pretend that we didn't see the previous declaration.
12513 if (getLangOpts().CPlusPlus && Name && DC && StdNamespace &&
12514 DC->Equals(getStdNamespace()) && Name->isStr("bad_alloc")) {
12515 // This is a declaration of or a reference to "std::bad_alloc".
12516 isStdBadAlloc = true;
12518 if (Previous.empty() && StdBadAlloc) {
12519 // std::bad_alloc has been implicitly declared (but made invisible to
12520 // name lookup). Fill in this implicit declaration as the previous
12521 // declaration, so that the declarations get chained appropriately.
12522 Previous.addDecl(getStdBadAlloc());
12526 // If we didn't find a previous declaration, and this is a reference
12527 // (or friend reference), move to the correct scope. In C++, we
12528 // also need to do a redeclaration lookup there, just in case
12529 // there's a shadow friend decl.
12530 if (Name && Previous.empty() &&
12531 (TUK == TUK_Reference || TUK == TUK_Friend)) {
12532 if (Invalid) goto CreateNewDecl;
12533 assert(SS.isEmpty());
12535 if (TUK == TUK_Reference) {
12536 // C++ [basic.scope.pdecl]p5:
12537 // -- for an elaborated-type-specifier of the form
12539 // class-key identifier
12541 // if the elaborated-type-specifier is used in the
12542 // decl-specifier-seq or parameter-declaration-clause of a
12543 // function defined in namespace scope, the identifier is
12544 // declared as a class-name in the namespace that contains
12545 // the declaration; otherwise, except as a friend
12546 // declaration, the identifier is declared in the smallest
12547 // non-class, non-function-prototype scope that contains the
12550 // C99 6.7.2.3p8 has a similar (but not identical!) provision for
12551 // C structs and unions.
12553 // It is an error in C++ to declare (rather than define) an enum
12554 // type, including via an elaborated type specifier. We'll
12555 // diagnose that later; for now, declare the enum in the same
12556 // scope as we would have picked for any other tag type.
12558 // GNU C also supports this behavior as part of its incomplete
12559 // enum types extension, while GNU C++ does not.
12561 // Find the context where we'll be declaring the tag.
12562 // FIXME: We would like to maintain the current DeclContext as the
12563 // lexical context,
12564 SearchDC = getTagInjectionContext(SearchDC);
12566 // Find the scope where we'll be declaring the tag.
12567 S = getTagInjectionScope(S, getLangOpts());
12569 assert(TUK == TUK_Friend);
12570 // C++ [namespace.memdef]p3:
12571 // If a friend declaration in a non-local class first declares a
12572 // class or function, the friend class or function is a member of
12573 // the innermost enclosing namespace.
12574 SearchDC = SearchDC->getEnclosingNamespaceContext();
12577 // In C++, we need to do a redeclaration lookup to properly
12578 // diagnose some problems.
12579 // FIXME: redeclaration lookup is also used (with and without C++) to find a
12580 // hidden declaration so that we don't get ambiguity errors when using a
12581 // type declared by an elaborated-type-specifier. In C that is not correct
12582 // and we should instead merge compatible types found by lookup.
12583 if (getLangOpts().CPlusPlus) {
12584 Previous.setRedeclarationKind(ForRedeclaration);
12585 LookupQualifiedName(Previous, SearchDC);
12587 Previous.setRedeclarationKind(ForRedeclaration);
12588 LookupName(Previous, S);
12592 // If we have a known previous declaration to use, then use it.
12593 if (Previous.empty() && SkipBody && SkipBody->Previous)
12594 Previous.addDecl(SkipBody->Previous);
12596 if (!Previous.empty()) {
12597 NamedDecl *PrevDecl = Previous.getFoundDecl();
12598 NamedDecl *DirectPrevDecl = Previous.getRepresentativeDecl();
12600 // It's okay to have a tag decl in the same scope as a typedef
12601 // which hides a tag decl in the same scope. Finding this
12602 // insanity with a redeclaration lookup can only actually happen
12605 // This is also okay for elaborated-type-specifiers, which is
12606 // technically forbidden by the current standard but which is
12607 // okay according to the likely resolution of an open issue;
12608 // see http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#407
12609 if (getLangOpts().CPlusPlus) {
12610 if (TypedefNameDecl *TD = dyn_cast<TypedefNameDecl>(PrevDecl)) {
12611 if (const TagType *TT = TD->getUnderlyingType()->getAs<TagType>()) {
12612 TagDecl *Tag = TT->getDecl();
12613 if (Tag->getDeclName() == Name &&
12614 Tag->getDeclContext()->getRedeclContext()
12615 ->Equals(TD->getDeclContext()->getRedeclContext())) {
12618 Previous.addDecl(Tag);
12619 Previous.resolveKind();
12625 // If this is a redeclaration of a using shadow declaration, it must
12626 // declare a tag in the same context. In MSVC mode, we allow a
12627 // redefinition if either context is within the other.
12628 if (auto *Shadow = dyn_cast<UsingShadowDecl>(DirectPrevDecl)) {
12629 auto *OldTag = dyn_cast<TagDecl>(PrevDecl);
12630 if (SS.isEmpty() && TUK != TUK_Reference && TUK != TUK_Friend &&
12631 isDeclInScope(Shadow, SearchDC, S, isExplicitSpecialization) &&
12632 !(OldTag && isAcceptableTagRedeclContext(
12633 *this, OldTag->getDeclContext(), SearchDC))) {
12634 Diag(KWLoc, diag::err_using_decl_conflict_reverse);
12635 Diag(Shadow->getTargetDecl()->getLocation(),
12636 diag::note_using_decl_target);
12637 Diag(Shadow->getUsingDecl()->getLocation(), diag::note_using_decl)
12639 // Recover by ignoring the old declaration.
12641 goto CreateNewDecl;
12645 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) {
12646 // If this is a use of a previous tag, or if the tag is already declared
12647 // in the same scope (so that the definition/declaration completes or
12648 // rementions the tag), reuse the decl.
12649 if (TUK == TUK_Reference || TUK == TUK_Friend ||
12650 isDeclInScope(DirectPrevDecl, SearchDC, S,
12651 SS.isNotEmpty() || isExplicitSpecialization)) {
12652 // Make sure that this wasn't declared as an enum and now used as a
12653 // struct or something similar.
12654 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind,
12655 TUK == TUK_Definition, KWLoc,
12657 bool SafeToContinue
12658 = (PrevTagDecl->getTagKind() != TTK_Enum &&
12660 if (SafeToContinue)
12661 Diag(KWLoc, diag::err_use_with_wrong_tag)
12663 << FixItHint::CreateReplacement(SourceRange(KWLoc),
12664 PrevTagDecl->getKindName());
12666 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name;
12667 Diag(PrevTagDecl->getLocation(), diag::note_previous_use);
12669 if (SafeToContinue)
12670 Kind = PrevTagDecl->getTagKind();
12672 // Recover by making this an anonymous redefinition.
12679 if (Kind == TTK_Enum && PrevTagDecl->getTagKind() == TTK_Enum) {
12680 const EnumDecl *PrevEnum = cast<EnumDecl>(PrevTagDecl);
12682 // If this is an elaborated-type-specifier for a scoped enumeration,
12683 // the 'class' keyword is not necessary and not permitted.
12684 if (TUK == TUK_Reference || TUK == TUK_Friend) {
12686 Diag(ScopedEnumKWLoc, diag::err_enum_class_reference)
12687 << PrevEnum->isScoped()
12688 << FixItHint::CreateRemoval(ScopedEnumKWLoc);
12689 return PrevTagDecl;
12692 QualType EnumUnderlyingTy;
12693 if (TypeSourceInfo *TI = EnumUnderlying.dyn_cast<TypeSourceInfo*>())
12694 EnumUnderlyingTy = TI->getType().getUnqualifiedType();
12695 else if (const Type *T = EnumUnderlying.dyn_cast<const Type*>())
12696 EnumUnderlyingTy = QualType(T, 0);
12698 // All conflicts with previous declarations are recovered by
12699 // returning the previous declaration, unless this is a definition,
12700 // in which case we want the caller to bail out.
12701 if (CheckEnumRedeclaration(NameLoc.isValid() ? NameLoc : KWLoc,
12702 ScopedEnum, EnumUnderlyingTy,
12703 EnumUnderlyingIsImplicit, PrevEnum))
12704 return TUK == TUK_Declaration ? PrevTagDecl : nullptr;
12707 // C++11 [class.mem]p1:
12708 // A member shall not be declared twice in the member-specification,
12709 // except that a nested class or member class template can be declared
12710 // and then later defined.
12711 if (TUK == TUK_Declaration && PrevDecl->isCXXClassMember() &&
12712 S->isDeclScope(PrevDecl)) {
12713 Diag(NameLoc, diag::ext_member_redeclared);
12714 Diag(PrevTagDecl->getLocation(), diag::note_previous_declaration);
12718 // If this is a use, just return the declaration we found, unless
12719 // we have attributes.
12720 if (TUK == TUK_Reference || TUK == TUK_Friend) {
12722 // FIXME: Diagnose these attributes. For now, we create a new
12723 // declaration to hold them.
12724 } else if (TUK == TUK_Reference &&
12725 (PrevTagDecl->getFriendObjectKind() ==
12726 Decl::FOK_Undeclared ||
12727 PP.getModuleContainingLocation(
12728 PrevDecl->getLocation()) !=
12729 PP.getModuleContainingLocation(KWLoc)) &&
12731 // This declaration is a reference to an existing entity, but
12732 // has different visibility from that entity: it either makes
12733 // a friend visible or it makes a type visible in a new module.
12734 // In either case, create a new declaration. We only do this if
12735 // the declaration would have meant the same thing if no prior
12736 // declaration were found, that is, if it was found in the same
12737 // scope where we would have injected a declaration.
12738 if (!getTagInjectionContext(CurContext)->getRedeclContext()
12739 ->Equals(PrevDecl->getDeclContext()->getRedeclContext()))
12740 return PrevTagDecl;
12741 // This is in the injected scope, create a new declaration in
12743 S = getTagInjectionScope(S, getLangOpts());
12745 return PrevTagDecl;
12749 // Diagnose attempts to redefine a tag.
12750 if (TUK == TUK_Definition) {
12751 if (NamedDecl *Def = PrevTagDecl->getDefinition()) {
12752 // If we're defining a specialization and the previous definition
12753 // is from an implicit instantiation, don't emit an error
12754 // here; we'll catch this in the general case below.
12755 bool IsExplicitSpecializationAfterInstantiation = false;
12756 if (isExplicitSpecialization) {
12757 if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(Def))
12758 IsExplicitSpecializationAfterInstantiation =
12759 RD->getTemplateSpecializationKind() !=
12760 TSK_ExplicitSpecialization;
12761 else if (EnumDecl *ED = dyn_cast<EnumDecl>(Def))
12762 IsExplicitSpecializationAfterInstantiation =
12763 ED->getTemplateSpecializationKind() !=
12764 TSK_ExplicitSpecialization;
12767 NamedDecl *Hidden = nullptr;
12768 if (SkipBody && getLangOpts().CPlusPlus &&
12769 !hasVisibleDefinition(Def, &Hidden)) {
12770 // There is a definition of this tag, but it is not visible. We
12771 // explicitly make use of C++'s one definition rule here, and
12772 // assume that this definition is identical to the hidden one
12773 // we already have. Make the existing definition visible and
12774 // use it in place of this one.
12775 SkipBody->ShouldSkip = true;
12776 makeMergedDefinitionVisible(Hidden, KWLoc);
12778 } else if (!IsExplicitSpecializationAfterInstantiation) {
12779 // A redeclaration in function prototype scope in C isn't
12780 // visible elsewhere, so merely issue a warning.
12781 if (!getLangOpts().CPlusPlus && S->containedInPrototypeScope())
12782 Diag(NameLoc, diag::warn_redefinition_in_param_list) << Name;
12784 Diag(NameLoc, diag::err_redefinition) << Name;
12785 Diag(Def->getLocation(), diag::note_previous_definition);
12786 // If this is a redefinition, recover by making this
12787 // struct be anonymous, which will make any later
12788 // references get the previous definition.
12794 // If the type is currently being defined, complain
12795 // about a nested redefinition.
12796 auto *TD = Context.getTagDeclType(PrevTagDecl)->getAsTagDecl();
12797 if (TD->isBeingDefined()) {
12798 Diag(NameLoc, diag::err_nested_redefinition) << Name;
12799 Diag(PrevTagDecl->getLocation(),
12800 diag::note_previous_definition);
12807 // Okay, this is definition of a previously declared or referenced
12808 // tag. We're going to create a new Decl for it.
12811 // Okay, we're going to make a redeclaration. If this is some kind
12812 // of reference, make sure we build the redeclaration in the same DC
12813 // as the original, and ignore the current access specifier.
12814 if (TUK == TUK_Friend || TUK == TUK_Reference) {
12815 SearchDC = PrevTagDecl->getDeclContext();
12819 // If we get here we have (another) forward declaration or we
12820 // have a definition. Just create a new decl.
12823 // If we get here, this is a definition of a new tag type in a nested
12824 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a
12825 // new decl/type. We set PrevDecl to NULL so that the entities
12826 // have distinct types.
12829 // If we get here, we're going to create a new Decl. If PrevDecl
12830 // is non-NULL, it's a definition of the tag declared by
12831 // PrevDecl. If it's NULL, we have a new definition.
12833 // Otherwise, PrevDecl is not a tag, but was found with tag
12834 // lookup. This is only actually possible in C++, where a few
12835 // things like templates still live in the tag namespace.
12837 // Use a better diagnostic if an elaborated-type-specifier
12838 // found the wrong kind of type on the first
12839 // (non-redeclaration) lookup.
12840 if ((TUK == TUK_Reference || TUK == TUK_Friend) &&
12841 !Previous.isForRedeclaration()) {
12843 if (isa<TypedefDecl>(PrevDecl)) Kind = 1;
12844 else if (isa<TypeAliasDecl>(PrevDecl)) Kind = 2;
12845 else if (isa<ClassTemplateDecl>(PrevDecl)) Kind = 3;
12846 Diag(NameLoc, diag::err_tag_reference_non_tag) << Kind;
12847 Diag(PrevDecl->getLocation(), diag::note_declared_at);
12850 // Otherwise, only diagnose if the declaration is in scope.
12851 } else if (!isDeclInScope(DirectPrevDecl, SearchDC, S,
12852 SS.isNotEmpty() || isExplicitSpecialization)) {
12855 // Diagnose implicit declarations introduced by elaborated types.
12856 } else if (TUK == TUK_Reference || TUK == TUK_Friend) {
12858 if (isa<TypedefDecl>(PrevDecl)) Kind = 1;
12859 else if (isa<TypeAliasDecl>(PrevDecl)) Kind = 2;
12860 else if (isa<ClassTemplateDecl>(PrevDecl)) Kind = 3;
12861 Diag(NameLoc, diag::err_tag_reference_conflict) << Kind;
12862 Diag(PrevDecl->getLocation(), diag::note_previous_decl) << PrevDecl;
12865 // Otherwise it's a declaration. Call out a particularly common
12867 } else if (TypedefNameDecl *TND = dyn_cast<TypedefNameDecl>(PrevDecl)) {
12869 if (isa<TypeAliasDecl>(PrevDecl)) Kind = 1;
12870 Diag(NameLoc, diag::err_tag_definition_of_typedef)
12871 << Name << Kind << TND->getUnderlyingType();
12872 Diag(PrevDecl->getLocation(), diag::note_previous_decl) << PrevDecl;
12875 // Otherwise, diagnose.
12877 // The tag name clashes with something else in the target scope,
12878 // issue an error and recover by making this tag be anonymous.
12879 Diag(NameLoc, diag::err_redefinition_different_kind) << Name;
12880 Diag(PrevDecl->getLocation(), diag::note_previous_definition);
12885 // The existing declaration isn't relevant to us; we're in a
12886 // new scope, so clear out the previous declaration.
12893 TagDecl *PrevDecl = nullptr;
12894 if (Previous.isSingleResult())
12895 PrevDecl = cast<TagDecl>(Previous.getFoundDecl());
12897 // If there is an identifier, use the location of the identifier as the
12898 // location of the decl, otherwise use the location of the struct/union
12900 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc;
12902 // Otherwise, create a new declaration. If there is a previous
12903 // declaration of the same entity, the two will be linked via
12907 bool IsForwardReference = false;
12908 if (Kind == TTK_Enum) {
12909 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.:
12910 // enum X { A, B, C } D; D should chain to X.
12911 New = EnumDecl::Create(Context, SearchDC, KWLoc, Loc, Name,
12912 cast_or_null<EnumDecl>(PrevDecl), ScopedEnum,
12913 ScopedEnumUsesClassTag, !EnumUnderlying.isNull());
12914 // If this is an undefined enum, warn.
12915 if (TUK != TUK_Definition && !Invalid) {
12917 if ((getLangOpts().CPlusPlus11 || getLangOpts().ObjC2) &&
12918 cast<EnumDecl>(New)->isFixed()) {
12919 // C++0x: 7.2p2: opaque-enum-declaration.
12920 // Conflicts are diagnosed above. Do nothing.
12922 else if (PrevDecl && (Def = cast<EnumDecl>(PrevDecl)->getDefinition())) {
12923 Diag(Loc, diag::ext_forward_ref_enum_def)
12925 Diag(Def->getLocation(), diag::note_previous_definition);
12927 unsigned DiagID = diag::ext_forward_ref_enum;
12928 if (getLangOpts().MSVCCompat)
12929 DiagID = diag::ext_ms_forward_ref_enum;
12930 else if (getLangOpts().CPlusPlus)
12931 DiagID = diag::err_forward_ref_enum;
12934 // If this is a forward-declared reference to an enumeration, make a
12935 // note of it; we won't actually be introducing the declaration into
12936 // the declaration context.
12937 if (TUK == TUK_Reference)
12938 IsForwardReference = true;
12942 if (EnumUnderlying) {
12943 EnumDecl *ED = cast<EnumDecl>(New);
12944 if (TypeSourceInfo *TI = EnumUnderlying.dyn_cast<TypeSourceInfo*>())
12945 ED->setIntegerTypeSourceInfo(TI);
12947 ED->setIntegerType(QualType(EnumUnderlying.get<const Type*>(), 0));
12948 ED->setPromotionType(ED->getIntegerType());
12951 // struct/union/class
12953 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.:
12954 // struct X { int A; } D; D should chain to X.
12955 if (getLangOpts().CPlusPlus) {
12956 // FIXME: Look for a way to use RecordDecl for simple structs.
12957 New = CXXRecordDecl::Create(Context, Kind, SearchDC, KWLoc, Loc, Name,
12958 cast_or_null<CXXRecordDecl>(PrevDecl));
12960 if (isStdBadAlloc && (!StdBadAlloc || getStdBadAlloc()->isImplicit()))
12961 StdBadAlloc = cast<CXXRecordDecl>(New);
12963 New = RecordDecl::Create(Context, Kind, SearchDC, KWLoc, Loc, Name,
12964 cast_or_null<RecordDecl>(PrevDecl));
12967 // C++11 [dcl.type]p3:
12968 // A type-specifier-seq shall not define a class or enumeration [...].
12969 if (getLangOpts().CPlusPlus && IsTypeSpecifier && TUK == TUK_Definition) {
12970 Diag(New->getLocation(), diag::err_type_defined_in_type_specifier)
12971 << Context.getTagDeclType(New);
12975 // Maybe add qualifier info.
12976 if (SS.isNotEmpty()) {
12978 // If this is either a declaration or a definition, check the
12979 // nested-name-specifier against the current context. We don't do this
12980 // for explicit specializations, because they have similar checking
12981 // (with more specific diagnostics) in the call to
12982 // CheckMemberSpecialization, below.
12983 if (!isExplicitSpecialization &&
12984 (TUK == TUK_Definition || TUK == TUK_Declaration) &&
12985 diagnoseQualifiedDeclaration(SS, DC, OrigName, Loc))
12988 New->setQualifierInfo(SS.getWithLocInContext(Context));
12989 if (TemplateParameterLists.size() > 0) {
12990 New->setTemplateParameterListsInfo(Context, TemplateParameterLists);
12997 if (RecordDecl *RD = dyn_cast<RecordDecl>(New)) {
12998 // Add alignment attributes if necessary; these attributes are checked when
12999 // the ASTContext lays out the structure.
13001 // It is important for implementing the correct semantics that this
13002 // happen here (in act on tag decl). The #pragma pack stack is
13003 // maintained as a result of parser callbacks which can occur at
13004 // many points during the parsing of a struct declaration (because
13005 // the #pragma tokens are effectively skipped over during the
13006 // parsing of the struct).
13007 if (TUK == TUK_Definition) {
13008 AddAlignmentAttributesForRecord(RD);
13009 AddMsStructLayoutForRecord(RD);
13013 if (ModulePrivateLoc.isValid()) {
13014 if (isExplicitSpecialization)
13015 Diag(New->getLocation(), diag::err_module_private_specialization)
13017 << FixItHint::CreateRemoval(ModulePrivateLoc);
13018 // __module_private__ does not apply to local classes. However, we only
13019 // diagnose this as an error when the declaration specifiers are
13020 // freestanding. Here, we just ignore the __module_private__.
13021 else if (!SearchDC->isFunctionOrMethod())
13022 New->setModulePrivate();
13025 // If this is a specialization of a member class (of a class template),
13026 // check the specialization.
13027 if (isExplicitSpecialization && CheckMemberSpecialization(New, Previous))
13030 // If we're declaring or defining a tag in function prototype scope in C,
13031 // note that this type can only be used within the function and add it to
13032 // the list of decls to inject into the function definition scope.
13033 if ((Name || Kind == TTK_Enum) &&
13034 getNonFieldDeclScope(S)->isFunctionPrototypeScope()) {
13035 if (getLangOpts().CPlusPlus) {
13036 // C++ [dcl.fct]p6:
13037 // Types shall not be defined in return or parameter types.
13038 if (TUK == TUK_Definition && !IsTypeSpecifier) {
13039 Diag(Loc, diag::err_type_defined_in_param_type)
13043 } else if (!PrevDecl) {
13044 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New);
13046 DeclsInPrototypeScope.push_back(New);
13050 New->setInvalidDecl();
13053 ProcessDeclAttributeList(S, New, Attr);
13055 // Set the lexical context. If the tag has a C++ scope specifier, the
13056 // lexical context will be different from the semantic context.
13057 New->setLexicalDeclContext(CurContext);
13059 // Mark this as a friend decl if applicable.
13060 // In Microsoft mode, a friend declaration also acts as a forward
13061 // declaration so we always pass true to setObjectOfFriendDecl to make
13062 // the tag name visible.
13063 if (TUK == TUK_Friend)
13064 New->setObjectOfFriendDecl(getLangOpts().MSVCCompat);
13066 // Set the access specifier.
13067 if (!Invalid && SearchDC->isRecord())
13068 SetMemberAccessSpecifier(New, PrevDecl, AS);
13070 if (TUK == TUK_Definition)
13071 New->startDefinition();
13073 // If this has an identifier, add it to the scope stack.
13074 if (TUK == TUK_Friend) {
13075 // We might be replacing an existing declaration in the lookup tables;
13076 // if so, borrow its access specifier.
13078 New->setAccess(PrevDecl->getAccess());
13080 DeclContext *DC = New->getDeclContext()->getRedeclContext();
13081 DC->makeDeclVisibleInContext(New);
13082 if (Name) // can be null along some error paths
13083 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC))
13084 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false);
13086 S = getNonFieldDeclScope(S);
13087 PushOnScopeChains(New, S, !IsForwardReference);
13088 if (IsForwardReference)
13089 SearchDC->makeDeclVisibleInContext(New);
13091 CurContext->addDecl(New);
13094 // If this is the C FILE type, notify the AST context.
13095 if (IdentifierInfo *II = New->getIdentifier())
13096 if (!New->isInvalidDecl() &&
13097 New->getDeclContext()->getRedeclContext()->isTranslationUnit() &&
13099 Context.setFILEDecl(New);
13102 mergeDeclAttributes(New, PrevDecl);
13104 // If there's a #pragma GCC visibility in scope, set the visibility of this
13106 AddPushedVisibilityAttribute(New);
13109 // In C++, don't return an invalid declaration. We can't recover well from
13110 // the cases where we make the type anonymous.
13111 return (Invalid && getLangOpts().CPlusPlus) ? nullptr : New;
13114 void Sema::ActOnTagStartDefinition(Scope *S, Decl *TagD) {
13115 AdjustDeclIfTemplate(TagD);
13116 TagDecl *Tag = cast<TagDecl>(TagD);
13118 // Enter the tag context.
13119 PushDeclContext(S, Tag);
13121 ActOnDocumentableDecl(TagD);
13123 // If there's a #pragma GCC visibility in scope, set the visibility of this
13125 AddPushedVisibilityAttribute(Tag);
13128 Decl *Sema::ActOnObjCContainerStartDefinition(Decl *IDecl) {
13129 assert(isa<ObjCContainerDecl>(IDecl) &&
13130 "ActOnObjCContainerStartDefinition - Not ObjCContainerDecl");
13131 DeclContext *OCD = cast<DeclContext>(IDecl);
13132 assert(getContainingDC(OCD) == CurContext &&
13133 "The next DeclContext should be lexically contained in the current one.");
13138 void Sema::ActOnStartCXXMemberDeclarations(Scope *S, Decl *TagD,
13139 SourceLocation FinalLoc,
13140 bool IsFinalSpelledSealed,
13141 SourceLocation LBraceLoc) {
13142 AdjustDeclIfTemplate(TagD);
13143 CXXRecordDecl *Record = cast<CXXRecordDecl>(TagD);
13145 FieldCollector->StartClass();
13147 if (!Record->getIdentifier())
13150 if (FinalLoc.isValid())
13151 Record->addAttr(new (Context)
13152 FinalAttr(FinalLoc, Context, IsFinalSpelledSealed));
13155 // [...] The class-name is also inserted into the scope of the
13156 // class itself; this is known as the injected-class-name. For
13157 // purposes of access checking, the injected-class-name is treated
13158 // as if it were a public member name.
13159 CXXRecordDecl *InjectedClassName
13160 = CXXRecordDecl::Create(Context, Record->getTagKind(), CurContext,
13161 Record->getLocStart(), Record->getLocation(),
13162 Record->getIdentifier(),
13163 /*PrevDecl=*/nullptr,
13164 /*DelayTypeCreation=*/true);
13165 Context.getTypeDeclType(InjectedClassName, Record);
13166 InjectedClassName->setImplicit();
13167 InjectedClassName->setAccess(AS_public);
13168 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate())
13169 InjectedClassName->setDescribedClassTemplate(Template);
13170 PushOnScopeChains(InjectedClassName, S);
13171 assert(InjectedClassName->isInjectedClassName() &&
13172 "Broken injected-class-name");
13175 void Sema::ActOnTagFinishDefinition(Scope *S, Decl *TagD,
13176 SourceLocation RBraceLoc) {
13177 AdjustDeclIfTemplate(TagD);
13178 TagDecl *Tag = cast<TagDecl>(TagD);
13179 Tag->setRBraceLoc(RBraceLoc);
13181 // Make sure we "complete" the definition even it is invalid.
13182 if (Tag->isBeingDefined()) {
13183 assert(Tag->isInvalidDecl() && "We should already have completed it");
13184 if (RecordDecl *RD = dyn_cast<RecordDecl>(Tag))
13185 RD->completeDefinition();
13188 if (isa<CXXRecordDecl>(Tag))
13189 FieldCollector->FinishClass();
13191 // Exit this scope of this tag's definition.
13194 if (getCurLexicalContext()->isObjCContainer() &&
13195 Tag->getDeclContext()->isFileContext())
13196 Tag->setTopLevelDeclInObjCContainer();
13198 // Notify the consumer that we've defined a tag.
13199 if (!Tag->isInvalidDecl())
13200 Consumer.HandleTagDeclDefinition(Tag);
13203 void Sema::ActOnObjCContainerFinishDefinition() {
13204 // Exit this scope of this interface definition.
13208 void Sema::ActOnObjCTemporaryExitContainerContext(DeclContext *DC) {
13209 assert(DC == CurContext && "Mismatch of container contexts");
13210 OriginalLexicalContext = DC;
13211 ActOnObjCContainerFinishDefinition();
13214 void Sema::ActOnObjCReenterContainerContext(DeclContext *DC) {
13215 ActOnObjCContainerStartDefinition(cast<Decl>(DC));
13216 OriginalLexicalContext = nullptr;
13219 void Sema::ActOnTagDefinitionError(Scope *S, Decl *TagD) {
13220 AdjustDeclIfTemplate(TagD);
13221 TagDecl *Tag = cast<TagDecl>(TagD);
13222 Tag->setInvalidDecl();
13224 // Make sure we "complete" the definition even it is invalid.
13225 if (Tag->isBeingDefined()) {
13226 if (RecordDecl *RD = dyn_cast<RecordDecl>(Tag))
13227 RD->completeDefinition();
13230 // We're undoing ActOnTagStartDefinition here, not
13231 // ActOnStartCXXMemberDeclarations, so we don't have to mess with
13232 // the FieldCollector.
13237 // Note that FieldName may be null for anonymous bitfields.
13238 ExprResult Sema::VerifyBitField(SourceLocation FieldLoc,
13239 IdentifierInfo *FieldName,
13240 QualType FieldTy, bool IsMsStruct,
13241 Expr *BitWidth, bool *ZeroWidth) {
13242 // Default to true; that shouldn't confuse checks for emptiness
13246 // C99 6.7.2.1p4 - verify the field type.
13247 // C++ 9.6p3: A bit-field shall have integral or enumeration type.
13248 if (!FieldTy->isDependentType() && !FieldTy->isIntegralOrEnumerationType()) {
13249 // Handle incomplete types with specific error.
13250 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete))
13251 return ExprError();
13253 return Diag(FieldLoc, diag::err_not_integral_type_bitfield)
13254 << FieldName << FieldTy << BitWidth->getSourceRange();
13255 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield)
13256 << FieldTy << BitWidth->getSourceRange();
13257 } else if (DiagnoseUnexpandedParameterPack(const_cast<Expr *>(BitWidth),
13258 UPPC_BitFieldWidth))
13259 return ExprError();
13261 // If the bit-width is type- or value-dependent, don't try to check
13263 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent())
13266 llvm::APSInt Value;
13267 ExprResult ICE = VerifyIntegerConstantExpression(BitWidth, &Value);
13268 if (ICE.isInvalid())
13270 BitWidth = ICE.get();
13272 if (Value != 0 && ZeroWidth)
13273 *ZeroWidth = false;
13275 // Zero-width bitfield is ok for anonymous field.
13276 if (Value == 0 && FieldName)
13277 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName;
13279 if (Value.isSigned() && Value.isNegative()) {
13281 return Diag(FieldLoc, diag::err_bitfield_has_negative_width)
13282 << FieldName << Value.toString(10);
13283 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width)
13284 << Value.toString(10);
13287 if (!FieldTy->isDependentType()) {
13288 uint64_t TypeStorageSize = Context.getTypeSize(FieldTy);
13289 uint64_t TypeWidth = Context.getIntWidth(FieldTy);
13290 bool BitfieldIsOverwide = Value.ugt(TypeWidth);
13292 // Over-wide bitfields are an error in C or when using the MSVC bitfield
13294 bool CStdConstraintViolation =
13295 BitfieldIsOverwide && !getLangOpts().CPlusPlus;
13296 bool MSBitfieldViolation =
13297 Value.ugt(TypeStorageSize) &&
13298 (IsMsStruct || Context.getTargetInfo().getCXXABI().isMicrosoft());
13299 if (CStdConstraintViolation || MSBitfieldViolation) {
13300 unsigned DiagWidth =
13301 CStdConstraintViolation ? TypeWidth : TypeStorageSize;
13303 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_width)
13304 << FieldName << (unsigned)Value.getZExtValue()
13305 << !CStdConstraintViolation << DiagWidth;
13307 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_width)
13308 << (unsigned)Value.getZExtValue() << !CStdConstraintViolation
13312 // Warn on types where the user might conceivably expect to get all
13313 // specified bits as value bits: that's all integral types other than
13315 if (BitfieldIsOverwide && !FieldTy->isBooleanType()) {
13317 Diag(FieldLoc, diag::warn_bitfield_width_exceeds_type_width)
13318 << FieldName << (unsigned)Value.getZExtValue()
13319 << (unsigned)TypeWidth;
13321 Diag(FieldLoc, diag::warn_anon_bitfield_width_exceeds_type_width)
13322 << (unsigned)Value.getZExtValue() << (unsigned)TypeWidth;
13329 /// ActOnField - Each field of a C struct/union is passed into this in order
13330 /// to create a FieldDecl object for it.
13331 Decl *Sema::ActOnField(Scope *S, Decl *TagD, SourceLocation DeclStart,
13332 Declarator &D, Expr *BitfieldWidth) {
13333 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD),
13334 DeclStart, D, static_cast<Expr*>(BitfieldWidth),
13335 /*InitStyle=*/ICIS_NoInit, AS_public);
13339 /// HandleField - Analyze a field of a C struct or a C++ data member.
13341 FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record,
13342 SourceLocation DeclStart,
13343 Declarator &D, Expr *BitWidth,
13344 InClassInitStyle InitStyle,
13345 AccessSpecifier AS) {
13346 IdentifierInfo *II = D.getIdentifier();
13347 SourceLocation Loc = DeclStart;
13348 if (II) Loc = D.getIdentifierLoc();
13350 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S);
13351 QualType T = TInfo->getType();
13352 if (getLangOpts().CPlusPlus) {
13353 CheckExtraCXXDefaultArguments(D);
13355 if (DiagnoseUnexpandedParameterPack(D.getIdentifierLoc(), TInfo,
13356 UPPC_DataMemberType)) {
13357 D.setInvalidType();
13359 TInfo = Context.getTrivialTypeSourceInfo(T, Loc);
13363 // TR 18037 does not allow fields to be declared with address spaces.
13364 if (T.getQualifiers().hasAddressSpace()) {
13365 Diag(Loc, diag::err_field_with_address_space);
13366 D.setInvalidType();
13369 // OpenCL v1.2 s6.9b,r & OpenCL v2.0 s6.12.5 - The following types cannot be
13370 // used as structure or union field: image, sampler, event or block types.
13371 if (LangOpts.OpenCL && (T->isEventT() || T->isImageType() ||
13372 T->isSamplerT() || T->isBlockPointerType())) {
13373 Diag(Loc, diag::err_opencl_type_struct_or_union_field) << T;
13374 D.setInvalidType();
13377 DiagnoseFunctionSpecifiers(D.getDeclSpec());
13379 if (D.getDeclSpec().isInlineSpecified())
13380 Diag(D.getDeclSpec().getInlineSpecLoc(), diag::err_inline_non_function)
13381 << getLangOpts().CPlusPlus1z;
13382 if (DeclSpec::TSCS TSCS = D.getDeclSpec().getThreadStorageClassSpec())
13383 Diag(D.getDeclSpec().getThreadStorageClassSpecLoc(),
13384 diag::err_invalid_thread)
13385 << DeclSpec::getSpecifierName(TSCS);
13387 // Check to see if this name was declared as a member previously
13388 NamedDecl *PrevDecl = nullptr;
13389 LookupResult Previous(*this, II, Loc, LookupMemberName, ForRedeclaration);
13390 LookupName(Previous, S);
13391 switch (Previous.getResultKind()) {
13392 case LookupResult::Found:
13393 case LookupResult::FoundUnresolvedValue:
13394 PrevDecl = Previous.getAsSingle<NamedDecl>();
13397 case LookupResult::FoundOverloaded:
13398 PrevDecl = Previous.getRepresentativeDecl();
13401 case LookupResult::NotFound:
13402 case LookupResult::NotFoundInCurrentInstantiation:
13403 case LookupResult::Ambiguous:
13406 Previous.suppressDiagnostics();
13408 if (PrevDecl && PrevDecl->isTemplateParameter()) {
13409 // Maybe we will complain about the shadowed template parameter.
13410 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl);
13411 // Just pretend that we didn't see the previous declaration.
13412 PrevDecl = nullptr;
13415 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S))
13416 PrevDecl = nullptr;
13419 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable);
13420 SourceLocation TSSL = D.getLocStart();
13422 = CheckFieldDecl(II, T, TInfo, Record, Loc, Mutable, BitWidth, InitStyle,
13423 TSSL, AS, PrevDecl, &D);
13425 if (NewFD->isInvalidDecl())
13426 Record->setInvalidDecl();
13428 if (D.getDeclSpec().isModulePrivateSpecified())
13429 NewFD->setModulePrivate();
13431 if (NewFD->isInvalidDecl() && PrevDecl) {
13432 // Don't introduce NewFD into scope; there's already something
13433 // with the same name in the same scope.
13435 PushOnScopeChains(NewFD, S);
13437 Record->addDecl(NewFD);
13442 /// \brief Build a new FieldDecl and check its well-formedness.
13444 /// This routine builds a new FieldDecl given the fields name, type,
13445 /// record, etc. \p PrevDecl should refer to any previous declaration
13446 /// with the same name and in the same scope as the field to be
13449 /// \returns a new FieldDecl.
13451 /// \todo The Declarator argument is a hack. It will be removed once
13452 FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T,
13453 TypeSourceInfo *TInfo,
13454 RecordDecl *Record, SourceLocation Loc,
13455 bool Mutable, Expr *BitWidth,
13456 InClassInitStyle InitStyle,
13457 SourceLocation TSSL,
13458 AccessSpecifier AS, NamedDecl *PrevDecl,
13460 IdentifierInfo *II = Name.getAsIdentifierInfo();
13461 bool InvalidDecl = false;
13462 if (D) InvalidDecl = D->isInvalidType();
13464 // If we receive a broken type, recover by assuming 'int' and
13465 // marking this declaration as invalid.
13467 InvalidDecl = true;
13471 QualType EltTy = Context.getBaseElementType(T);
13472 if (!EltTy->isDependentType()) {
13473 if (RequireCompleteType(Loc, EltTy, diag::err_field_incomplete)) {
13474 // Fields of incomplete type force their record to be invalid.
13475 Record->setInvalidDecl();
13476 InvalidDecl = true;
13479 EltTy->isIncompleteType(&Def);
13480 if (Def && Def->isInvalidDecl()) {
13481 Record->setInvalidDecl();
13482 InvalidDecl = true;
13487 // OpenCL v1.2 s6.9.c: bitfields are not supported.
13488 if (BitWidth && getLangOpts().OpenCL) {
13489 Diag(Loc, diag::err_opencl_bitfields);
13490 InvalidDecl = true;
13493 // C99 6.7.2.1p8: A member of a structure or union may have any type other
13494 // than a variably modified type.
13495 if (!InvalidDecl && T->isVariablyModifiedType()) {
13496 bool SizeIsNegative;
13497 llvm::APSInt Oversized;
13499 TypeSourceInfo *FixedTInfo =
13500 TryToFixInvalidVariablyModifiedTypeSourceInfo(TInfo, Context,
13504 Diag(Loc, diag::warn_illegal_constant_array_size);
13505 TInfo = FixedTInfo;
13506 T = FixedTInfo->getType();
13508 if (SizeIsNegative)
13509 Diag(Loc, diag::err_typecheck_negative_array_size);
13510 else if (Oversized.getBoolValue())
13511 Diag(Loc, diag::err_array_too_large)
13512 << Oversized.toString(10);
13514 Diag(Loc, diag::err_typecheck_field_variable_size);
13515 InvalidDecl = true;
13519 // Fields can not have abstract class types
13520 if (!InvalidDecl && RequireNonAbstractType(Loc, T,
13521 diag::err_abstract_type_in_decl,
13522 AbstractFieldType))
13523 InvalidDecl = true;
13525 bool ZeroWidth = false;
13527 BitWidth = nullptr;
13528 // If this is declared as a bit-field, check the bit-field.
13530 BitWidth = VerifyBitField(Loc, II, T, Record->isMsStruct(Context), BitWidth,
13533 InvalidDecl = true;
13534 BitWidth = nullptr;
13539 // Check that 'mutable' is consistent with the type of the declaration.
13540 if (!InvalidDecl && Mutable) {
13541 unsigned DiagID = 0;
13542 if (T->isReferenceType())
13543 DiagID = getLangOpts().MSVCCompat ? diag::ext_mutable_reference
13544 : diag::err_mutable_reference;
13545 else if (T.isConstQualified())
13546 DiagID = diag::err_mutable_const;
13549 SourceLocation ErrLoc = Loc;
13550 if (D && D->getDeclSpec().getStorageClassSpecLoc().isValid())
13551 ErrLoc = D->getDeclSpec().getStorageClassSpecLoc();
13552 Diag(ErrLoc, DiagID);
13553 if (DiagID != diag::ext_mutable_reference) {
13555 InvalidDecl = true;
13560 // C++11 [class.union]p8 (DR1460):
13561 // At most one variant member of a union may have a
13562 // brace-or-equal-initializer.
13563 if (InitStyle != ICIS_NoInit)
13564 checkDuplicateDefaultInit(*this, cast<CXXRecordDecl>(Record), Loc);
13566 FieldDecl *NewFD = FieldDecl::Create(Context, Record, TSSL, Loc, II, T, TInfo,
13567 BitWidth, Mutable, InitStyle);
13569 NewFD->setInvalidDecl();
13571 if (PrevDecl && !isa<TagDecl>(PrevDecl)) {
13572 Diag(Loc, diag::err_duplicate_member) << II;
13573 Diag(PrevDecl->getLocation(), diag::note_previous_declaration);
13574 NewFD->setInvalidDecl();
13577 if (!InvalidDecl && getLangOpts().CPlusPlus) {
13578 if (Record->isUnion()) {
13579 if (const RecordType *RT = EltTy->getAs<RecordType>()) {
13580 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl());
13581 if (RDecl->getDefinition()) {
13582 // C++ [class.union]p1: An object of a class with a non-trivial
13583 // constructor, a non-trivial copy constructor, a non-trivial
13584 // destructor, or a non-trivial copy assignment operator
13585 // cannot be a member of a union, nor can an array of such
13587 if (CheckNontrivialField(NewFD))
13588 NewFD->setInvalidDecl();
13592 // C++ [class.union]p1: If a union contains a member of reference type,
13593 // the program is ill-formed, except when compiling with MSVC extensions
13595 if (EltTy->isReferenceType()) {
13596 Diag(NewFD->getLocation(), getLangOpts().MicrosoftExt ?
13597 diag::ext_union_member_of_reference_type :
13598 diag::err_union_member_of_reference_type)
13599 << NewFD->getDeclName() << EltTy;
13600 if (!getLangOpts().MicrosoftExt)
13601 NewFD->setInvalidDecl();
13606 // FIXME: We need to pass in the attributes given an AST
13607 // representation, not a parser representation.
13609 // FIXME: The current scope is almost... but not entirely... correct here.
13610 ProcessDeclAttributes(getCurScope(), NewFD, *D);
13612 if (NewFD->hasAttrs())
13613 CheckAlignasUnderalignment(NewFD);
13616 // In auto-retain/release, infer strong retension for fields of
13617 // retainable type.
13618 if (getLangOpts().ObjCAutoRefCount && inferObjCARCLifetime(NewFD))
13619 NewFD->setInvalidDecl();
13621 if (T.isObjCGCWeak())
13622 Diag(Loc, diag::warn_attribute_weak_on_field);
13624 NewFD->setAccess(AS);
13628 bool Sema::CheckNontrivialField(FieldDecl *FD) {
13630 assert(getLangOpts().CPlusPlus && "valid check only for C++");
13632 if (FD->isInvalidDecl() || FD->getType()->isDependentType())
13635 QualType EltTy = Context.getBaseElementType(FD->getType());
13636 if (const RecordType *RT = EltTy->getAs<RecordType>()) {
13637 CXXRecordDecl *RDecl = cast<CXXRecordDecl>(RT->getDecl());
13638 if (RDecl->getDefinition()) {
13639 // We check for copy constructors before constructors
13640 // because otherwise we'll never get complaints about
13641 // copy constructors.
13643 CXXSpecialMember member = CXXInvalid;
13644 // We're required to check for any non-trivial constructors. Since the
13645 // implicit default constructor is suppressed if there are any
13646 // user-declared constructors, we just need to check that there is a
13647 // trivial default constructor and a trivial copy constructor. (We don't
13648 // worry about move constructors here, since this is a C++98 check.)
13649 if (RDecl->hasNonTrivialCopyConstructor())
13650 member = CXXCopyConstructor;
13651 else if (!RDecl->hasTrivialDefaultConstructor())
13652 member = CXXDefaultConstructor;
13653 else if (RDecl->hasNonTrivialCopyAssignment())
13654 member = CXXCopyAssignment;
13655 else if (RDecl->hasNonTrivialDestructor())
13656 member = CXXDestructor;
13658 if (member != CXXInvalid) {
13659 if (!getLangOpts().CPlusPlus11 &&
13660 getLangOpts().ObjCAutoRefCount && RDecl->hasObjectMember()) {
13661 // Objective-C++ ARC: it is an error to have a non-trivial field of
13662 // a union. However, system headers in Objective-C programs
13663 // occasionally have Objective-C lifetime objects within unions,
13664 // and rather than cause the program to fail, we make those
13665 // members unavailable.
13666 SourceLocation Loc = FD->getLocation();
13667 if (getSourceManager().isInSystemHeader(Loc)) {
13668 if (!FD->hasAttr<UnavailableAttr>())
13669 FD->addAttr(UnavailableAttr::CreateImplicit(Context, "",
13670 UnavailableAttr::IR_ARCFieldWithOwnership, Loc));
13675 Diag(FD->getLocation(), getLangOpts().CPlusPlus11 ?
13676 diag::warn_cxx98_compat_nontrivial_union_or_anon_struct_member :
13677 diag::err_illegal_union_or_anon_struct_member)
13678 << FD->getParent()->isUnion() << FD->getDeclName() << member;
13679 DiagnoseNontrivial(RDecl, member);
13680 return !getLangOpts().CPlusPlus11;
13688 /// TranslateIvarVisibility - Translate visibility from a token ID to an
13689 /// AST enum value.
13690 static ObjCIvarDecl::AccessControl
13691 TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) {
13692 switch (ivarVisibility) {
13693 default: llvm_unreachable("Unknown visitibility kind");
13694 case tok::objc_private: return ObjCIvarDecl::Private;
13695 case tok::objc_public: return ObjCIvarDecl::Public;
13696 case tok::objc_protected: return ObjCIvarDecl::Protected;
13697 case tok::objc_package: return ObjCIvarDecl::Package;
13701 /// ActOnIvar - Each ivar field of an objective-c class is passed into this
13702 /// in order to create an IvarDecl object for it.
13703 Decl *Sema::ActOnIvar(Scope *S,
13704 SourceLocation DeclStart,
13705 Declarator &D, Expr *BitfieldWidth,
13706 tok::ObjCKeywordKind Visibility) {
13708 IdentifierInfo *II = D.getIdentifier();
13709 Expr *BitWidth = (Expr*)BitfieldWidth;
13710 SourceLocation Loc = DeclStart;
13711 if (II) Loc = D.getIdentifierLoc();
13713 // FIXME: Unnamed fields can be handled in various different ways, for
13714 // example, unnamed unions inject all members into the struct namespace!
13716 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S);
13717 QualType T = TInfo->getType();
13720 // 6.7.2.1p3, 6.7.2.1p4
13721 BitWidth = VerifyBitField(Loc, II, T, /*IsMsStruct*/false, BitWidth).get();
13723 D.setInvalidType();
13730 if (T->isReferenceType()) {
13731 Diag(Loc, diag::err_ivar_reference_type);
13732 D.setInvalidType();
13734 // C99 6.7.2.1p8: A member of a structure or union may have any type other
13735 // than a variably modified type.
13736 else if (T->isVariablyModifiedType()) {
13737 Diag(Loc, diag::err_typecheck_ivar_variable_size);
13738 D.setInvalidType();
13741 // Get the visibility (access control) for this ivar.
13742 ObjCIvarDecl::AccessControl ac =
13743 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility)
13744 : ObjCIvarDecl::None;
13745 // Must set ivar's DeclContext to its enclosing interface.
13746 ObjCContainerDecl *EnclosingDecl = cast<ObjCContainerDecl>(CurContext);
13747 if (!EnclosingDecl || EnclosingDecl->isInvalidDecl())
13749 ObjCContainerDecl *EnclosingContext;
13750 if (ObjCImplementationDecl *IMPDecl =
13751 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) {
13752 if (LangOpts.ObjCRuntime.isFragile()) {
13753 // Case of ivar declared in an implementation. Context is that of its class.
13754 EnclosingContext = IMPDecl->getClassInterface();
13755 assert(EnclosingContext && "Implementation has no class interface!");
13758 EnclosingContext = EnclosingDecl;
13760 if (ObjCCategoryDecl *CDecl =
13761 dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) {
13762 if (LangOpts.ObjCRuntime.isFragile() || !CDecl->IsClassExtension()) {
13763 Diag(Loc, diag::err_misplaced_ivar) << CDecl->IsClassExtension();
13767 EnclosingContext = EnclosingDecl;
13770 // Construct the decl.
13771 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, EnclosingContext,
13772 DeclStart, Loc, II, T,
13773 TInfo, ac, (Expr *)BitfieldWidth);
13776 NamedDecl *PrevDecl = LookupSingleName(S, II, Loc, LookupMemberName,
13778 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S)
13779 && !isa<TagDecl>(PrevDecl)) {
13780 Diag(Loc, diag::err_duplicate_member) << II;
13781 Diag(PrevDecl->getLocation(), diag::note_previous_declaration);
13782 NewID->setInvalidDecl();
13786 // Process attributes attached to the ivar.
13787 ProcessDeclAttributes(S, NewID, D);
13789 if (D.isInvalidType())
13790 NewID->setInvalidDecl();
13792 // In ARC, infer 'retaining' for ivars of retainable type.
13793 if (getLangOpts().ObjCAutoRefCount && inferObjCARCLifetime(NewID))
13794 NewID->setInvalidDecl();
13796 if (D.getDeclSpec().isModulePrivateSpecified())
13797 NewID->setModulePrivate();
13800 // FIXME: When interfaces are DeclContexts, we'll need to add
13801 // these to the interface.
13803 IdResolver.AddDecl(NewID);
13806 if (LangOpts.ObjCRuntime.isNonFragile() &&
13807 !NewID->isInvalidDecl() && isa<ObjCInterfaceDecl>(EnclosingDecl))
13808 Diag(Loc, diag::warn_ivars_in_interface);
13813 /// ActOnLastBitfield - This routine handles synthesized bitfields rules for
13814 /// class and class extensions. For every class \@interface and class
13815 /// extension \@interface, if the last ivar is a bitfield of any type,
13816 /// then add an implicit `char :0` ivar to the end of that interface.
13817 void Sema::ActOnLastBitfield(SourceLocation DeclLoc,
13818 SmallVectorImpl<Decl *> &AllIvarDecls) {
13819 if (LangOpts.ObjCRuntime.isFragile() || AllIvarDecls.empty())
13822 Decl *ivarDecl = AllIvarDecls[AllIvarDecls.size()-1];
13823 ObjCIvarDecl *Ivar = cast<ObjCIvarDecl>(ivarDecl);
13825 if (!Ivar->isBitField() || Ivar->getBitWidthValue(Context) == 0)
13827 ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(CurContext);
13829 if (ObjCCategoryDecl *CD = dyn_cast<ObjCCategoryDecl>(CurContext)) {
13830 if (!CD->IsClassExtension())
13833 // No need to add this to end of @implementation.
13837 // All conditions are met. Add a new bitfield to the tail end of ivars.
13838 llvm::APInt Zero(Context.getTypeSize(Context.IntTy), 0);
13839 Expr * BW = IntegerLiteral::Create(Context, Zero, Context.IntTy, DeclLoc);
13841 Ivar = ObjCIvarDecl::Create(Context, cast<ObjCContainerDecl>(CurContext),
13842 DeclLoc, DeclLoc, nullptr,
13844 Context.getTrivialTypeSourceInfo(Context.CharTy,
13846 ObjCIvarDecl::Private, BW,
13848 AllIvarDecls.push_back(Ivar);
13851 void Sema::ActOnFields(Scope *S, SourceLocation RecLoc, Decl *EnclosingDecl,
13852 ArrayRef<Decl *> Fields, SourceLocation LBrac,
13853 SourceLocation RBrac, AttributeList *Attr) {
13854 assert(EnclosingDecl && "missing record or interface decl");
13856 // If this is an Objective-C @implementation or category and we have
13857 // new fields here we should reset the layout of the interface since
13858 // it will now change.
13859 if (!Fields.empty() && isa<ObjCContainerDecl>(EnclosingDecl)) {
13860 ObjCContainerDecl *DC = cast<ObjCContainerDecl>(EnclosingDecl);
13861 switch (DC->getKind()) {
13863 case Decl::ObjCCategory:
13864 Context.ResetObjCLayout(cast<ObjCCategoryDecl>(DC)->getClassInterface());
13866 case Decl::ObjCImplementation:
13868 ResetObjCLayout(cast<ObjCImplementationDecl>(DC)->getClassInterface());
13873 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl);
13875 // Start counting up the number of named members; make sure to include
13876 // members of anonymous structs and unions in the total.
13877 unsigned NumNamedMembers = 0;
13879 for (const auto *I : Record->decls()) {
13880 if (const auto *IFD = dyn_cast<IndirectFieldDecl>(I))
13881 if (IFD->getDeclName())
13886 // Verify that all the fields are okay.
13887 SmallVector<FieldDecl*, 32> RecFields;
13889 bool ARCErrReported = false;
13890 for (ArrayRef<Decl *>::iterator i = Fields.begin(), end = Fields.end();
13892 FieldDecl *FD = cast<FieldDecl>(*i);
13894 // Get the type for the field.
13895 const Type *FDTy = FD->getType().getTypePtr();
13897 if (!FD->isAnonymousStructOrUnion()) {
13898 // Remember all fields written by the user.
13899 RecFields.push_back(FD);
13902 // If the field is already invalid for some reason, don't emit more
13903 // diagnostics about it.
13904 if (FD->isInvalidDecl()) {
13905 EnclosingDecl->setInvalidDecl();
13910 // A structure or union shall not contain a member with
13911 // incomplete or function type (hence, a structure shall not
13912 // contain an instance of itself, but may contain a pointer to
13913 // an instance of itself), except that the last member of a
13914 // structure with more than one named member may have incomplete
13915 // array type; such a structure (and any union containing,
13916 // possibly recursively, a member that is such a structure)
13917 // shall not be a member of a structure or an element of an
13919 if (FDTy->isFunctionType()) {
13920 // Field declared as a function.
13921 Diag(FD->getLocation(), diag::err_field_declared_as_function)
13922 << FD->getDeclName();
13923 FD->setInvalidDecl();
13924 EnclosingDecl->setInvalidDecl();
13926 } else if (FDTy->isIncompleteArrayType() && Record &&
13927 ((i + 1 == Fields.end() && !Record->isUnion()) ||
13928 ((getLangOpts().MicrosoftExt ||
13929 getLangOpts().CPlusPlus) &&
13930 (i + 1 == Fields.end() || Record->isUnion())))) {
13931 // Flexible array member.
13932 // Microsoft and g++ is more permissive regarding flexible array.
13933 // It will accept flexible array in union and also
13934 // as the sole element of a struct/class.
13935 unsigned DiagID = 0;
13936 if (Record->isUnion())
13937 DiagID = getLangOpts().MicrosoftExt
13938 ? diag::ext_flexible_array_union_ms
13939 : getLangOpts().CPlusPlus
13940 ? diag::ext_flexible_array_union_gnu
13941 : diag::err_flexible_array_union;
13942 else if (NumNamedMembers < 1)
13943 DiagID = getLangOpts().MicrosoftExt
13944 ? diag::ext_flexible_array_empty_aggregate_ms
13945 : getLangOpts().CPlusPlus
13946 ? diag::ext_flexible_array_empty_aggregate_gnu
13947 : diag::err_flexible_array_empty_aggregate;
13950 Diag(FD->getLocation(), DiagID) << FD->getDeclName()
13951 << Record->getTagKind();
13952 // While the layout of types that contain virtual bases is not specified
13953 // by the C++ standard, both the Itanium and Microsoft C++ ABIs place
13954 // virtual bases after the derived members. This would make a flexible
13955 // array member declared at the end of an object not adjacent to the end
13957 if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(Record))
13958 if (RD->getNumVBases() != 0)
13959 Diag(FD->getLocation(), diag::err_flexible_array_virtual_base)
13960 << FD->getDeclName() << Record->getTagKind();
13961 if (!getLangOpts().C99)
13962 Diag(FD->getLocation(), diag::ext_c99_flexible_array_member)
13963 << FD->getDeclName() << Record->getTagKind();
13965 // If the element type has a non-trivial destructor, we would not
13966 // implicitly destroy the elements, so disallow it for now.
13968 // FIXME: GCC allows this. We should probably either implicitly delete
13969 // the destructor of the containing class, or just allow this.
13970 QualType BaseElem = Context.getBaseElementType(FD->getType());
13971 if (!BaseElem->isDependentType() && BaseElem.isDestructedType()) {
13972 Diag(FD->getLocation(), diag::err_flexible_array_has_nontrivial_dtor)
13973 << FD->getDeclName() << FD->getType();
13974 FD->setInvalidDecl();
13975 EnclosingDecl->setInvalidDecl();
13978 // Okay, we have a legal flexible array member at the end of the struct.
13979 Record->setHasFlexibleArrayMember(true);
13980 } else if (!FDTy->isDependentType() &&
13981 RequireCompleteType(FD->getLocation(), FD->getType(),
13982 diag::err_field_incomplete)) {
13984 FD->setInvalidDecl();
13985 EnclosingDecl->setInvalidDecl();
13987 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) {
13988 if (Record && FDTTy->getDecl()->hasFlexibleArrayMember()) {
13989 // A type which contains a flexible array member is considered to be a
13990 // flexible array member.
13991 Record->setHasFlexibleArrayMember(true);
13992 if (!Record->isUnion()) {
13993 // If this is a struct/class and this is not the last element, reject
13994 // it. Note that GCC supports variable sized arrays in the middle of
13996 if (i + 1 != Fields.end())
13997 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct)
13998 << FD->getDeclName() << FD->getType();
14000 // We support flexible arrays at the end of structs in
14001 // other structs as an extension.
14002 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct)
14003 << FD->getDeclName();
14007 if (isa<ObjCContainerDecl>(EnclosingDecl) &&
14008 RequireNonAbstractType(FD->getLocation(), FD->getType(),
14009 diag::err_abstract_type_in_decl,
14010 AbstractIvarType)) {
14011 // Ivars can not have abstract class types
14012 FD->setInvalidDecl();
14014 if (Record && FDTTy->getDecl()->hasObjectMember())
14015 Record->setHasObjectMember(true);
14016 if (Record && FDTTy->getDecl()->hasVolatileMember())
14017 Record->setHasVolatileMember(true);
14018 } else if (FDTy->isObjCObjectType()) {
14019 /// A field cannot be an Objective-c object
14020 Diag(FD->getLocation(), diag::err_statically_allocated_object)
14021 << FixItHint::CreateInsertion(FD->getLocation(), "*");
14022 QualType T = Context.getObjCObjectPointerType(FD->getType());
14024 } else if (getLangOpts().ObjCAutoRefCount && Record && !ARCErrReported &&
14025 (!getLangOpts().CPlusPlus || Record->isUnion())) {
14026 // It's an error in ARC if a field has lifetime.
14027 // We don't want to report this in a system header, though,
14028 // so we just make the field unavailable.
14029 // FIXME: that's really not sufficient; we need to make the type
14030 // itself invalid to, say, initialize or copy.
14031 QualType T = FD->getType();
14032 Qualifiers::ObjCLifetime lifetime = T.getObjCLifetime();
14033 if (lifetime && lifetime != Qualifiers::OCL_ExplicitNone) {
14034 SourceLocation loc = FD->getLocation();
14035 if (getSourceManager().isInSystemHeader(loc)) {
14036 if (!FD->hasAttr<UnavailableAttr>()) {
14037 FD->addAttr(UnavailableAttr::CreateImplicit(Context, "",
14038 UnavailableAttr::IR_ARCFieldWithOwnership, loc));
14041 Diag(FD->getLocation(), diag::err_arc_objc_object_in_tag)
14042 << T->isBlockPointerType() << Record->getTagKind();
14044 ARCErrReported = true;
14046 } else if (getLangOpts().ObjC1 &&
14047 getLangOpts().getGC() != LangOptions::NonGC &&
14048 Record && !Record->hasObjectMember()) {
14049 if (FD->getType()->isObjCObjectPointerType() ||
14050 FD->getType().isObjCGCStrong())
14051 Record->setHasObjectMember(true);
14052 else if (Context.getAsArrayType(FD->getType())) {
14053 QualType BaseType = Context.getBaseElementType(FD->getType());
14054 if (BaseType->isRecordType() &&
14055 BaseType->getAs<RecordType>()->getDecl()->hasObjectMember())
14056 Record->setHasObjectMember(true);
14057 else if (BaseType->isObjCObjectPointerType() ||
14058 BaseType.isObjCGCStrong())
14059 Record->setHasObjectMember(true);
14062 if (Record && FD->getType().isVolatileQualified())
14063 Record->setHasVolatileMember(true);
14064 // Keep track of the number of named members.
14065 if (FD->getIdentifier())
14069 // Okay, we successfully defined 'Record'.
14071 bool Completed = false;
14072 if (CXXRecordDecl *CXXRecord = dyn_cast<CXXRecordDecl>(Record)) {
14073 if (!CXXRecord->isInvalidDecl()) {
14074 // Set access bits correctly on the directly-declared conversions.
14075 for (CXXRecordDecl::conversion_iterator
14076 I = CXXRecord->conversion_begin(),
14077 E = CXXRecord->conversion_end(); I != E; ++I)
14078 I.setAccess((*I)->getAccess());
14081 if (!CXXRecord->isDependentType()) {
14082 if (CXXRecord->hasUserDeclaredDestructor()) {
14083 // Adjust user-defined destructor exception spec.
14084 if (getLangOpts().CPlusPlus11)
14085 AdjustDestructorExceptionSpec(CXXRecord,
14086 CXXRecord->getDestructor());
14089 if (!CXXRecord->isInvalidDecl()) {
14090 // Add any implicitly-declared members to this class.
14091 AddImplicitlyDeclaredMembersToClass(CXXRecord);
14093 // If we have virtual base classes, we may end up finding multiple
14094 // final overriders for a given virtual function. Check for this
14096 if (CXXRecord->getNumVBases()) {
14097 CXXFinalOverriderMap FinalOverriders;
14098 CXXRecord->getFinalOverriders(FinalOverriders);
14100 for (CXXFinalOverriderMap::iterator M = FinalOverriders.begin(),
14101 MEnd = FinalOverriders.end();
14103 for (OverridingMethods::iterator SO = M->second.begin(),
14104 SOEnd = M->second.end();
14105 SO != SOEnd; ++SO) {
14106 assert(SO->second.size() > 0 &&
14107 "Virtual function without overridding functions?");
14108 if (SO->second.size() == 1)
14111 // C++ [class.virtual]p2:
14112 // In a derived class, if a virtual member function of a base
14113 // class subobject has more than one final overrider the
14114 // program is ill-formed.
14115 Diag(Record->getLocation(), diag::err_multiple_final_overriders)
14116 << (const NamedDecl *)M->first << Record;
14117 Diag(M->first->getLocation(),
14118 diag::note_overridden_virtual_function);
14119 for (OverridingMethods::overriding_iterator
14120 OM = SO->second.begin(),
14121 OMEnd = SO->second.end();
14123 Diag(OM->Method->getLocation(), diag::note_final_overrider)
14124 << (const NamedDecl *)M->first << OM->Method->getParent();
14126 Record->setInvalidDecl();
14129 CXXRecord->completeDefinition(&FinalOverriders);
14137 Record->completeDefinition();
14139 if (Record->hasAttrs()) {
14140 CheckAlignasUnderalignment(Record);
14142 if (const MSInheritanceAttr *IA = Record->getAttr<MSInheritanceAttr>())
14143 checkMSInheritanceAttrOnDefinition(cast<CXXRecordDecl>(Record),
14144 IA->getRange(), IA->getBestCase(),
14145 IA->getSemanticSpelling());
14148 // Check if the structure/union declaration is a type that can have zero
14149 // size in C. For C this is a language extension, for C++ it may cause
14150 // compatibility problems.
14151 bool CheckForZeroSize;
14152 if (!getLangOpts().CPlusPlus) {
14153 CheckForZeroSize = true;
14155 // For C++ filter out types that cannot be referenced in C code.
14156 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record);
14158 CXXRecord->getLexicalDeclContext()->isExternCContext() &&
14159 !CXXRecord->isDependentType() &&
14160 CXXRecord->isCLike();
14162 if (CheckForZeroSize) {
14163 bool ZeroSize = true;
14164 bool IsEmpty = true;
14165 unsigned NonBitFields = 0;
14166 for (RecordDecl::field_iterator I = Record->field_begin(),
14167 E = Record->field_end();
14168 (NonBitFields == 0 || ZeroSize) && I != E; ++I) {
14170 if (I->isUnnamedBitfield()) {
14171 if (I->getBitWidthValue(Context) > 0)
14175 QualType FieldType = I->getType();
14176 if (FieldType->isIncompleteType() ||
14177 !Context.getTypeSizeInChars(FieldType).isZero())
14182 // Empty structs are an extension in C (C99 6.7.2.1p7). They are
14183 // allowed in C++, but warn if its declaration is inside
14184 // extern "C" block.
14186 Diag(RecLoc, getLangOpts().CPlusPlus ?
14187 diag::warn_zero_size_struct_union_in_extern_c :
14188 diag::warn_zero_size_struct_union_compat)
14189 << IsEmpty << Record->isUnion() << (NonBitFields > 1);
14192 // Structs without named members are extension in C (C99 6.7.2.1p7),
14193 // but are accepted by GCC.
14194 if (NonBitFields == 0 && !getLangOpts().CPlusPlus) {
14195 Diag(RecLoc, IsEmpty ? diag::ext_empty_struct_union :
14196 diag::ext_no_named_members_in_struct_union)
14197 << Record->isUnion();
14201 ObjCIvarDecl **ClsFields =
14202 reinterpret_cast<ObjCIvarDecl**>(RecFields.data());
14203 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) {
14204 ID->setEndOfDefinitionLoc(RBrac);
14205 // Add ivar's to class's DeclContext.
14206 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) {
14207 ClsFields[i]->setLexicalDeclContext(ID);
14208 ID->addDecl(ClsFields[i]);
14210 // Must enforce the rule that ivars in the base classes may not be
14212 if (ID->getSuperClass())
14213 DiagnoseDuplicateIvars(ID, ID->getSuperClass());
14214 } else if (ObjCImplementationDecl *IMPDecl =
14215 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) {
14216 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl");
14217 for (unsigned I = 0, N = RecFields.size(); I != N; ++I)
14218 // Ivar declared in @implementation never belongs to the implementation.
14219 // Only it is in implementation's lexical context.
14220 ClsFields[I]->setLexicalDeclContext(IMPDecl);
14221 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac);
14222 IMPDecl->setIvarLBraceLoc(LBrac);
14223 IMPDecl->setIvarRBraceLoc(RBrac);
14224 } else if (ObjCCategoryDecl *CDecl =
14225 dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) {
14226 // case of ivars in class extension; all other cases have been
14227 // reported as errors elsewhere.
14228 // FIXME. Class extension does not have a LocEnd field.
14229 // CDecl->setLocEnd(RBrac);
14230 // Add ivar's to class extension's DeclContext.
14231 // Diagnose redeclaration of private ivars.
14232 ObjCInterfaceDecl *IDecl = CDecl->getClassInterface();
14233 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) {
14235 if (const ObjCIvarDecl *ClsIvar =
14236 IDecl->getIvarDecl(ClsFields[i]->getIdentifier())) {
14237 Diag(ClsFields[i]->getLocation(),
14238 diag::err_duplicate_ivar_declaration);
14239 Diag(ClsIvar->getLocation(), diag::note_previous_definition);
14242 for (const auto *Ext : IDecl->known_extensions()) {
14243 if (const ObjCIvarDecl *ClsExtIvar
14244 = Ext->getIvarDecl(ClsFields[i]->getIdentifier())) {
14245 Diag(ClsFields[i]->getLocation(),
14246 diag::err_duplicate_ivar_declaration);
14247 Diag(ClsExtIvar->getLocation(), diag::note_previous_definition);
14252 ClsFields[i]->setLexicalDeclContext(CDecl);
14253 CDecl->addDecl(ClsFields[i]);
14255 CDecl->setIvarLBraceLoc(LBrac);
14256 CDecl->setIvarRBraceLoc(RBrac);
14261 ProcessDeclAttributeList(S, Record, Attr);
14264 /// \brief Determine whether the given integral value is representable within
14265 /// the given type T.
14266 static bool isRepresentableIntegerValue(ASTContext &Context,
14267 llvm::APSInt &Value,
14269 assert(T->isIntegralType(Context) && "Integral type required!");
14270 unsigned BitWidth = Context.getIntWidth(T);
14272 if (Value.isUnsigned() || Value.isNonNegative()) {
14273 if (T->isSignedIntegerOrEnumerationType())
14275 return Value.getActiveBits() <= BitWidth;
14277 return Value.getMinSignedBits() <= BitWidth;
14280 // \brief Given an integral type, return the next larger integral type
14281 // (or a NULL type of no such type exists).
14282 static QualType getNextLargerIntegralType(ASTContext &Context, QualType T) {
14283 // FIXME: Int128/UInt128 support, which also needs to be introduced into
14284 // enum checking below.
14285 assert(T->isIntegralType(Context) && "Integral type required!");
14286 const unsigned NumTypes = 4;
14287 QualType SignedIntegralTypes[NumTypes] = {
14288 Context.ShortTy, Context.IntTy, Context.LongTy, Context.LongLongTy
14290 QualType UnsignedIntegralTypes[NumTypes] = {
14291 Context.UnsignedShortTy, Context.UnsignedIntTy, Context.UnsignedLongTy,
14292 Context.UnsignedLongLongTy
14295 unsigned BitWidth = Context.getTypeSize(T);
14296 QualType *Types = T->isSignedIntegerOrEnumerationType()? SignedIntegralTypes
14297 : UnsignedIntegralTypes;
14298 for (unsigned I = 0; I != NumTypes; ++I)
14299 if (Context.getTypeSize(Types[I]) > BitWidth)
14305 EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum,
14306 EnumConstantDecl *LastEnumConst,
14307 SourceLocation IdLoc,
14308 IdentifierInfo *Id,
14310 unsigned IntWidth = Context.getTargetInfo().getIntWidth();
14311 llvm::APSInt EnumVal(IntWidth);
14314 if (Val && DiagnoseUnexpandedParameterPack(Val, UPPC_EnumeratorValue))
14318 Val = DefaultLvalueConversion(Val).get();
14321 if (Enum->isDependentType() || Val->isTypeDependent())
14322 EltTy = Context.DependentTy;
14324 SourceLocation ExpLoc;
14325 if (getLangOpts().CPlusPlus11 && Enum->isFixed() &&
14326 !getLangOpts().MSVCCompat) {
14327 // C++11 [dcl.enum]p5: If the underlying type is fixed, [...] the
14328 // constant-expression in the enumerator-definition shall be a converted
14329 // constant expression of the underlying type.
14330 EltTy = Enum->getIntegerType();
14331 ExprResult Converted =
14332 CheckConvertedConstantExpression(Val, EltTy, EnumVal,
14334 if (Converted.isInvalid())
14337 Val = Converted.get();
14338 } else if (!Val->isValueDependent() &&
14339 !(Val = VerifyIntegerConstantExpression(Val,
14340 &EnumVal).get())) {
14341 // C99 6.7.2.2p2: Make sure we have an integer constant expression.
14343 if (Enum->isFixed()) {
14344 EltTy = Enum->getIntegerType();
14346 // In Obj-C and Microsoft mode, require the enumeration value to be
14347 // representable in the underlying type of the enumeration. In C++11,
14348 // we perform a non-narrowing conversion as part of converted constant
14349 // expression checking.
14350 if (!isRepresentableIntegerValue(Context, EnumVal, EltTy)) {
14351 if (getLangOpts().MSVCCompat) {
14352 Diag(IdLoc, diag::ext_enumerator_too_large) << EltTy;
14353 Val = ImpCastExprToType(Val, EltTy, CK_IntegralCast).get();
14355 Diag(IdLoc, diag::err_enumerator_too_large) << EltTy;
14357 Val = ImpCastExprToType(Val, EltTy,
14358 EltTy->isBooleanType() ?
14359 CK_IntegralToBoolean : CK_IntegralCast)
14361 } else if (getLangOpts().CPlusPlus) {
14362 // C++11 [dcl.enum]p5:
14363 // If the underlying type is not fixed, the type of each enumerator
14364 // is the type of its initializing value:
14365 // - If an initializer is specified for an enumerator, the
14366 // initializing value has the same type as the expression.
14367 EltTy = Val->getType();
14370 // The expression that defines the value of an enumeration constant
14371 // shall be an integer constant expression that has a value
14372 // representable as an int.
14374 // Complain if the value is not representable in an int.
14375 if (!isRepresentableIntegerValue(Context, EnumVal, Context.IntTy))
14376 Diag(IdLoc, diag::ext_enum_value_not_int)
14377 << EnumVal.toString(10) << Val->getSourceRange()
14378 << (EnumVal.isUnsigned() || EnumVal.isNonNegative());
14379 else if (!Context.hasSameType(Val->getType(), Context.IntTy)) {
14380 // Force the type of the expression to 'int'.
14381 Val = ImpCastExprToType(Val, Context.IntTy, CK_IntegralCast).get();
14383 EltTy = Val->getType();
14390 if (Enum->isDependentType())
14391 EltTy = Context.DependentTy;
14392 else if (!LastEnumConst) {
14393 // C++0x [dcl.enum]p5:
14394 // If the underlying type is not fixed, the type of each enumerator
14395 // is the type of its initializing value:
14396 // - If no initializer is specified for the first enumerator, the
14397 // initializing value has an unspecified integral type.
14399 // GCC uses 'int' for its unspecified integral type, as does
14401 if (Enum->isFixed()) {
14402 EltTy = Enum->getIntegerType();
14405 EltTy = Context.IntTy;
14408 // Assign the last value + 1.
14409 EnumVal = LastEnumConst->getInitVal();
14411 EltTy = LastEnumConst->getType();
14413 // Check for overflow on increment.
14414 if (EnumVal < LastEnumConst->getInitVal()) {
14415 // C++0x [dcl.enum]p5:
14416 // If the underlying type is not fixed, the type of each enumerator
14417 // is the type of its initializing value:
14419 // - Otherwise the type of the initializing value is the same as
14420 // the type of the initializing value of the preceding enumerator
14421 // unless the incremented value is not representable in that type,
14422 // in which case the type is an unspecified integral type
14423 // sufficient to contain the incremented value. If no such type
14424 // exists, the program is ill-formed.
14425 QualType T = getNextLargerIntegralType(Context, EltTy);
14426 if (T.isNull() || Enum->isFixed()) {
14427 // There is no integral type larger enough to represent this
14428 // value. Complain, then allow the value to wrap around.
14429 EnumVal = LastEnumConst->getInitVal();
14430 EnumVal = EnumVal.zext(EnumVal.getBitWidth() * 2);
14432 if (Enum->isFixed())
14433 // When the underlying type is fixed, this is ill-formed.
14434 Diag(IdLoc, diag::err_enumerator_wrapped)
14435 << EnumVal.toString(10)
14438 Diag(IdLoc, diag::ext_enumerator_increment_too_large)
14439 << EnumVal.toString(10);
14444 // Retrieve the last enumerator's value, extent that type to the
14445 // type that is supposed to be large enough to represent the incremented
14446 // value, then increment.
14447 EnumVal = LastEnumConst->getInitVal();
14448 EnumVal.setIsSigned(EltTy->isSignedIntegerOrEnumerationType());
14449 EnumVal = EnumVal.zextOrTrunc(Context.getIntWidth(EltTy));
14452 // If we're not in C++, diagnose the overflow of enumerator values,
14453 // which in C99 means that the enumerator value is not representable in
14454 // an int (C99 6.7.2.2p2). However, we support GCC's extension that
14455 // permits enumerator values that are representable in some larger
14457 if (!getLangOpts().CPlusPlus && !T.isNull())
14458 Diag(IdLoc, diag::warn_enum_value_overflow);
14459 } else if (!getLangOpts().CPlusPlus &&
14460 !isRepresentableIntegerValue(Context, EnumVal, EltTy)) {
14461 // Enforce C99 6.7.2.2p2 even when we compute the next value.
14462 Diag(IdLoc, diag::ext_enum_value_not_int)
14463 << EnumVal.toString(10) << 1;
14468 if (!EltTy->isDependentType()) {
14469 // Make the enumerator value match the signedness and size of the
14470 // enumerator's type.
14471 EnumVal = EnumVal.extOrTrunc(Context.getIntWidth(EltTy));
14472 EnumVal.setIsSigned(EltTy->isSignedIntegerOrEnumerationType());
14475 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy,
14479 Sema::SkipBodyInfo Sema::shouldSkipAnonEnumBody(Scope *S, IdentifierInfo *II,
14480 SourceLocation IILoc) {
14481 if (!(getLangOpts().Modules || getLangOpts().ModulesLocalVisibility) ||
14482 !getLangOpts().CPlusPlus)
14483 return SkipBodyInfo();
14485 // We have an anonymous enum definition. Look up the first enumerator to
14486 // determine if we should merge the definition with an existing one and
14488 NamedDecl *PrevDecl = LookupSingleName(S, II, IILoc, LookupOrdinaryName,
14490 auto *PrevECD = dyn_cast_or_null<EnumConstantDecl>(PrevDecl);
14492 return SkipBodyInfo();
14494 EnumDecl *PrevED = cast<EnumDecl>(PrevECD->getDeclContext());
14496 if (!PrevED->getDeclName() && !hasVisibleDefinition(PrevED, &Hidden)) {
14498 Skip.Previous = Hidden;
14502 return SkipBodyInfo();
14505 Decl *Sema::ActOnEnumConstant(Scope *S, Decl *theEnumDecl, Decl *lastEnumConst,
14506 SourceLocation IdLoc, IdentifierInfo *Id,
14507 AttributeList *Attr,
14508 SourceLocation EqualLoc, Expr *Val) {
14509 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl);
14510 EnumConstantDecl *LastEnumConst =
14511 cast_or_null<EnumConstantDecl>(lastEnumConst);
14513 // The scope passed in may not be a decl scope. Zip up the scope tree until
14514 // we find one that is.
14515 S = getNonFieldDeclScope(S);
14517 // Verify that there isn't already something declared with this name in this
14519 NamedDecl *PrevDecl = LookupSingleName(S, Id, IdLoc, LookupOrdinaryName,
14521 if (PrevDecl && PrevDecl->isTemplateParameter()) {
14522 // Maybe we will complain about the shadowed template parameter.
14523 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl);
14524 // Just pretend that we didn't see the previous declaration.
14525 PrevDecl = nullptr;
14528 // C++ [class.mem]p15:
14529 // If T is the name of a class, then each of the following shall have a name
14530 // different from T:
14531 // - every enumerator of every member of class T that is an unscoped
14533 if (!TheEnumDecl->isScoped())
14534 DiagnoseClassNameShadow(TheEnumDecl->getDeclContext(),
14535 DeclarationNameInfo(Id, IdLoc));
14537 EnumConstantDecl *New =
14538 CheckEnumConstant(TheEnumDecl, LastEnumConst, IdLoc, Id, Val);
14543 // When in C++, we may get a TagDecl with the same name; in this case the
14544 // enum constant will 'hide' the tag.
14545 assert((getLangOpts().CPlusPlus || !isa<TagDecl>(PrevDecl)) &&
14546 "Received TagDecl when not in C++!");
14547 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S) &&
14548 shouldLinkPossiblyHiddenDecl(PrevDecl, New)) {
14549 if (isa<EnumConstantDecl>(PrevDecl))
14550 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id;
14552 Diag(IdLoc, diag::err_redefinition) << Id;
14553 Diag(PrevDecl->getLocation(), diag::note_previous_definition);
14558 // Process attributes.
14559 if (Attr) ProcessDeclAttributeList(S, New, Attr);
14561 // Register this decl in the current scope stack.
14562 New->setAccess(TheEnumDecl->getAccess());
14563 PushOnScopeChains(New, S);
14565 ActOnDocumentableDecl(New);
14570 // Returns true when the enum initial expression does not trigger the
14571 // duplicate enum warning. A few common cases are exempted as follows:
14572 // Element2 = Element1
14573 // Element2 = Element1 + 1
14574 // Element2 = Element1 - 1
14575 // Where Element2 and Element1 are from the same enum.
14576 static bool ValidDuplicateEnum(EnumConstantDecl *ECD, EnumDecl *Enum) {
14577 Expr *InitExpr = ECD->getInitExpr();
14580 InitExpr = InitExpr->IgnoreImpCasts();
14582 if (BinaryOperator *BO = dyn_cast<BinaryOperator>(InitExpr)) {
14583 if (!BO->isAdditiveOp())
14585 IntegerLiteral *IL = dyn_cast<IntegerLiteral>(BO->getRHS());
14588 if (IL->getValue() != 1)
14591 InitExpr = BO->getLHS();
14594 // This checks if the elements are from the same enum.
14595 DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(InitExpr);
14599 EnumConstantDecl *EnumConstant = dyn_cast<EnumConstantDecl>(DRE->getDecl());
14603 if (cast<EnumDecl>(TagDecl::castFromDeclContext(ECD->getDeclContext())) !=
14613 bool isTombstoneOrEmptyKey;
14614 DupKey(int64_t val, bool isTombstoneOrEmptyKey)
14615 : val(val), isTombstoneOrEmptyKey(isTombstoneOrEmptyKey) {}
14618 static DupKey GetDupKey(const llvm::APSInt& Val) {
14619 return DupKey(Val.isSigned() ? Val.getSExtValue() : Val.getZExtValue(),
14623 struct DenseMapInfoDupKey {
14624 static DupKey getEmptyKey() { return DupKey(0, true); }
14625 static DupKey getTombstoneKey() { return DupKey(1, true); }
14626 static unsigned getHashValue(const DupKey Key) {
14627 return (unsigned)(Key.val * 37);
14629 static bool isEqual(const DupKey& LHS, const DupKey& RHS) {
14630 return LHS.isTombstoneOrEmptyKey == RHS.isTombstoneOrEmptyKey &&
14631 LHS.val == RHS.val;
14634 } // end anonymous namespace
14636 // Emits a warning when an element is implicitly set a value that
14637 // a previous element has already been set to.
14638 static void CheckForDuplicateEnumValues(Sema &S, ArrayRef<Decl *> Elements,
14640 QualType EnumType) {
14641 if (S.Diags.isIgnored(diag::warn_duplicate_enum_values, Enum->getLocation()))
14643 // Avoid anonymous enums
14644 if (!Enum->getIdentifier())
14647 // Only check for small enums.
14648 if (Enum->getNumPositiveBits() > 63 || Enum->getNumNegativeBits() > 64)
14651 typedef SmallVector<EnumConstantDecl *, 3> ECDVector;
14652 typedef SmallVector<ECDVector *, 3> DuplicatesVector;
14654 typedef llvm::PointerUnion<EnumConstantDecl*, ECDVector*> DeclOrVector;
14655 typedef llvm::DenseMap<DupKey, DeclOrVector, DenseMapInfoDupKey>
14658 DuplicatesVector DupVector;
14659 ValueToVectorMap EnumMap;
14661 // Populate the EnumMap with all values represented by enum constants without
14663 for (unsigned i = 0, e = Elements.size(); i != e; ++i) {
14664 EnumConstantDecl *ECD = cast_or_null<EnumConstantDecl>(Elements[i]);
14666 // Null EnumConstantDecl means a previous diagnostic has been emitted for
14667 // this constant. Skip this enum since it may be ill-formed.
14672 if (ECD->getInitExpr())
14675 DupKey Key = GetDupKey(ECD->getInitVal());
14676 DeclOrVector &Entry = EnumMap[Key];
14678 // First time encountering this value.
14679 if (Entry.isNull())
14683 // Create vectors for any values that has duplicates.
14684 for (unsigned i = 0, e = Elements.size(); i != e; ++i) {
14685 EnumConstantDecl *ECD = cast<EnumConstantDecl>(Elements[i]);
14686 if (!ValidDuplicateEnum(ECD, Enum))
14689 DupKey Key = GetDupKey(ECD->getInitVal());
14691 DeclOrVector& Entry = EnumMap[Key];
14692 if (Entry.isNull())
14695 if (EnumConstantDecl *D = Entry.dyn_cast<EnumConstantDecl*>()) {
14696 // Ensure constants are different.
14700 // Create new vector and push values onto it.
14701 ECDVector *Vec = new ECDVector();
14703 Vec->push_back(ECD);
14705 // Update entry to point to the duplicates vector.
14708 // Store the vector somewhere we can consult later for quick emission of
14710 DupVector.push_back(Vec);
14714 ECDVector *Vec = Entry.get<ECDVector*>();
14715 // Make sure constants are not added more than once.
14716 if (*Vec->begin() == ECD)
14719 Vec->push_back(ECD);
14722 // Emit diagnostics.
14723 for (DuplicatesVector::iterator DupVectorIter = DupVector.begin(),
14724 DupVectorEnd = DupVector.end();
14725 DupVectorIter != DupVectorEnd; ++DupVectorIter) {
14726 ECDVector *Vec = *DupVectorIter;
14727 assert(Vec->size() > 1 && "ECDVector should have at least 2 elements.");
14729 // Emit warning for one enum constant.
14730 ECDVector::iterator I = Vec->begin();
14731 S.Diag((*I)->getLocation(), diag::warn_duplicate_enum_values)
14732 << (*I)->getName() << (*I)->getInitVal().toString(10)
14733 << (*I)->getSourceRange();
14736 // Emit one note for each of the remaining enum constants with
14738 for (ECDVector::iterator E = Vec->end(); I != E; ++I)
14739 S.Diag((*I)->getLocation(), diag::note_duplicate_element)
14740 << (*I)->getName() << (*I)->getInitVal().toString(10)
14741 << (*I)->getSourceRange();
14746 bool Sema::IsValueInFlagEnum(const EnumDecl *ED, const llvm::APInt &Val,
14747 bool AllowMask) const {
14748 assert(ED->hasAttr<FlagEnumAttr>() && "looking for value in non-flag enum");
14749 assert(ED->isCompleteDefinition() && "expected enum definition");
14751 auto R = FlagBitsCache.insert(std::make_pair(ED, llvm::APInt()));
14752 llvm::APInt &FlagBits = R.first->second;
14755 for (auto *E : ED->enumerators()) {
14756 const auto &EVal = E->getInitVal();
14757 // Only single-bit enumerators introduce new flag values.
14758 if (EVal.isPowerOf2())
14759 FlagBits = FlagBits.zextOrSelf(EVal.getBitWidth()) | EVal;
14763 // A value is in a flag enum if either its bits are a subset of the enum's
14764 // flag bits (the first condition) or we are allowing masks and the same is
14765 // true of its complement (the second condition). When masks are allowed, we
14766 // allow the common idiom of ~(enum1 | enum2) to be a valid enum value.
14768 // While it's true that any value could be used as a mask, the assumption is
14769 // that a mask will have all of the insignificant bits set. Anything else is
14770 // likely a logic error.
14771 llvm::APInt FlagMask = ~FlagBits.zextOrTrunc(Val.getBitWidth());
14772 return !(FlagMask & Val) || (AllowMask && !(FlagMask & ~Val));
14775 void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc,
14776 SourceLocation RBraceLoc, Decl *EnumDeclX,
14777 ArrayRef<Decl *> Elements,
14778 Scope *S, AttributeList *Attr) {
14779 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX);
14780 QualType EnumType = Context.getTypeDeclType(Enum);
14783 ProcessDeclAttributeList(S, Enum, Attr);
14785 if (Enum->isDependentType()) {
14786 for (unsigned i = 0, e = Elements.size(); i != e; ++i) {
14787 EnumConstantDecl *ECD =
14788 cast_or_null<EnumConstantDecl>(Elements[i]);
14789 if (!ECD) continue;
14791 ECD->setType(EnumType);
14794 Enum->completeDefinition(Context.DependentTy, Context.DependentTy, 0, 0);
14798 // TODO: If the result value doesn't fit in an int, it must be a long or long
14799 // long value. ISO C does not support this, but GCC does as an extension,
14801 unsigned IntWidth = Context.getTargetInfo().getIntWidth();
14802 unsigned CharWidth = Context.getTargetInfo().getCharWidth();
14803 unsigned ShortWidth = Context.getTargetInfo().getShortWidth();
14805 // Verify that all the values are okay, compute the size of the values, and
14806 // reverse the list.
14807 unsigned NumNegativeBits = 0;
14808 unsigned NumPositiveBits = 0;
14810 // Keep track of whether all elements have type int.
14811 bool AllElementsInt = true;
14813 for (unsigned i = 0, e = Elements.size(); i != e; ++i) {
14814 EnumConstantDecl *ECD =
14815 cast_or_null<EnumConstantDecl>(Elements[i]);
14816 if (!ECD) continue; // Already issued a diagnostic.
14818 const llvm::APSInt &InitVal = ECD->getInitVal();
14820 // Keep track of the size of positive and negative values.
14821 if (InitVal.isUnsigned() || InitVal.isNonNegative())
14822 NumPositiveBits = std::max(NumPositiveBits,
14823 (unsigned)InitVal.getActiveBits());
14825 NumNegativeBits = std::max(NumNegativeBits,
14826 (unsigned)InitVal.getMinSignedBits());
14828 // Keep track of whether every enum element has type int (very commmon).
14829 if (AllElementsInt)
14830 AllElementsInt = ECD->getType() == Context.IntTy;
14833 // Figure out the type that should be used for this enum.
14835 unsigned BestWidth;
14837 // C++0x N3000 [conv.prom]p3:
14838 // An rvalue of an unscoped enumeration type whose underlying
14839 // type is not fixed can be converted to an rvalue of the first
14840 // of the following types that can represent all the values of
14841 // the enumeration: int, unsigned int, long int, unsigned long
14842 // int, long long int, or unsigned long long int.
14844 // An identifier declared as an enumeration constant has type int.
14845 // The C99 rule is modified by a gcc extension
14846 QualType BestPromotionType;
14848 bool Packed = Enum->hasAttr<PackedAttr>();
14849 // -fshort-enums is the equivalent to specifying the packed attribute on all
14850 // enum definitions.
14851 if (LangOpts.ShortEnums)
14854 if (Enum->isFixed()) {
14855 BestType = Enum->getIntegerType();
14856 if (BestType->isPromotableIntegerType())
14857 BestPromotionType = Context.getPromotedIntegerType(BestType);
14859 BestPromotionType = BestType;
14861 BestWidth = Context.getIntWidth(BestType);
14863 else if (NumNegativeBits) {
14864 // If there is a negative value, figure out the smallest integer type (of
14865 // int/long/longlong) that fits.
14866 // If it's packed, check also if it fits a char or a short.
14867 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) {
14868 BestType = Context.SignedCharTy;
14869 BestWidth = CharWidth;
14870 } else if (Packed && NumNegativeBits <= ShortWidth &&
14871 NumPositiveBits < ShortWidth) {
14872 BestType = Context.ShortTy;
14873 BestWidth = ShortWidth;
14874 } else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) {
14875 BestType = Context.IntTy;
14876 BestWidth = IntWidth;
14878 BestWidth = Context.getTargetInfo().getLongWidth();
14880 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) {
14881 BestType = Context.LongTy;
14883 BestWidth = Context.getTargetInfo().getLongLongWidth();
14885 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth)
14886 Diag(Enum->getLocation(), diag::ext_enum_too_large);
14887 BestType = Context.LongLongTy;
14890 BestPromotionType = (BestWidth <= IntWidth ? Context.IntTy : BestType);
14892 // If there is no negative value, figure out the smallest type that fits
14893 // all of the enumerator values.
14894 // If it's packed, check also if it fits a char or a short.
14895 if (Packed && NumPositiveBits <= CharWidth) {
14896 BestType = Context.UnsignedCharTy;
14897 BestPromotionType = Context.IntTy;
14898 BestWidth = CharWidth;
14899 } else if (Packed && NumPositiveBits <= ShortWidth) {
14900 BestType = Context.UnsignedShortTy;
14901 BestPromotionType = Context.IntTy;
14902 BestWidth = ShortWidth;
14903 } else if (NumPositiveBits <= IntWidth) {
14904 BestType = Context.UnsignedIntTy;
14905 BestWidth = IntWidth;
14907 = (NumPositiveBits == BestWidth || !getLangOpts().CPlusPlus)
14908 ? Context.UnsignedIntTy : Context.IntTy;
14909 } else if (NumPositiveBits <=
14910 (BestWidth = Context.getTargetInfo().getLongWidth())) {
14911 BestType = Context.UnsignedLongTy;
14913 = (NumPositiveBits == BestWidth || !getLangOpts().CPlusPlus)
14914 ? Context.UnsignedLongTy : Context.LongTy;
14916 BestWidth = Context.getTargetInfo().getLongLongWidth();
14917 assert(NumPositiveBits <= BestWidth &&
14918 "How could an initializer get larger than ULL?");
14919 BestType = Context.UnsignedLongLongTy;
14921 = (NumPositiveBits == BestWidth || !getLangOpts().CPlusPlus)
14922 ? Context.UnsignedLongLongTy : Context.LongLongTy;
14926 // Loop over all of the enumerator constants, changing their types to match
14927 // the type of the enum if needed.
14928 for (auto *D : Elements) {
14929 auto *ECD = cast_or_null<EnumConstantDecl>(D);
14930 if (!ECD) continue; // Already issued a diagnostic.
14932 // Standard C says the enumerators have int type, but we allow, as an
14933 // extension, the enumerators to be larger than int size. If each
14934 // enumerator value fits in an int, type it as an int, otherwise type it the
14935 // same as the enumerator decl itself. This means that in "enum { X = 1U }"
14936 // that X has type 'int', not 'unsigned'.
14938 // Determine whether the value fits into an int.
14939 llvm::APSInt InitVal = ECD->getInitVal();
14941 // If it fits into an integer type, force it. Otherwise force it to match
14942 // the enum decl type.
14946 if (!getLangOpts().CPlusPlus &&
14947 !Enum->isFixed() &&
14948 isRepresentableIntegerValue(Context, InitVal, Context.IntTy)) {
14949 NewTy = Context.IntTy;
14950 NewWidth = IntWidth;
14952 } else if (ECD->getType() == BestType) {
14953 // Already the right type!
14954 if (getLangOpts().CPlusPlus)
14955 // C++ [dcl.enum]p4: Following the closing brace of an
14956 // enum-specifier, each enumerator has the type of its
14958 ECD->setType(EnumType);
14962 NewWidth = BestWidth;
14963 NewSign = BestType->isSignedIntegerOrEnumerationType();
14966 // Adjust the APSInt value.
14967 InitVal = InitVal.extOrTrunc(NewWidth);
14968 InitVal.setIsSigned(NewSign);
14969 ECD->setInitVal(InitVal);
14971 // Adjust the Expr initializer and type.
14972 if (ECD->getInitExpr() &&
14973 !Context.hasSameType(NewTy, ECD->getInitExpr()->getType()))
14974 ECD->setInitExpr(ImplicitCastExpr::Create(Context, NewTy,
14976 ECD->getInitExpr(),
14977 /*base paths*/ nullptr,
14979 if (getLangOpts().CPlusPlus)
14980 // C++ [dcl.enum]p4: Following the closing brace of an
14981 // enum-specifier, each enumerator has the type of its
14983 ECD->setType(EnumType);
14985 ECD->setType(NewTy);
14988 Enum->completeDefinition(BestType, BestPromotionType,
14989 NumPositiveBits, NumNegativeBits);
14991 CheckForDuplicateEnumValues(*this, Elements, Enum, EnumType);
14993 if (Enum->hasAttr<FlagEnumAttr>()) {
14994 for (Decl *D : Elements) {
14995 EnumConstantDecl *ECD = cast_or_null<EnumConstantDecl>(D);
14996 if (!ECD) continue; // Already issued a diagnostic.
14998 llvm::APSInt InitVal = ECD->getInitVal();
14999 if (InitVal != 0 && !InitVal.isPowerOf2() &&
15000 !IsValueInFlagEnum(Enum, InitVal, true))
15001 Diag(ECD->getLocation(), diag::warn_flag_enum_constant_out_of_range)
15006 // Now that the enum type is defined, ensure it's not been underaligned.
15007 if (Enum->hasAttrs())
15008 CheckAlignasUnderalignment(Enum);
15011 Decl *Sema::ActOnFileScopeAsmDecl(Expr *expr,
15012 SourceLocation StartLoc,
15013 SourceLocation EndLoc) {
15014 StringLiteral *AsmString = cast<StringLiteral>(expr);
15016 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext,
15017 AsmString, StartLoc,
15019 CurContext->addDecl(New);
15023 static void checkModuleImportContext(Sema &S, Module *M,
15024 SourceLocation ImportLoc, DeclContext *DC,
15025 bool FromInclude = false) {
15026 SourceLocation ExternCLoc;
15028 if (auto *LSD = dyn_cast<LinkageSpecDecl>(DC)) {
15029 switch (LSD->getLanguage()) {
15030 case LinkageSpecDecl::lang_c:
15031 if (ExternCLoc.isInvalid())
15032 ExternCLoc = LSD->getLocStart();
15034 case LinkageSpecDecl::lang_cxx:
15037 DC = LSD->getParent();
15040 while (isa<LinkageSpecDecl>(DC))
15041 DC = DC->getParent();
15043 if (!isa<TranslationUnitDecl>(DC)) {
15044 S.Diag(ImportLoc, (FromInclude && S.isModuleVisible(M))
15045 ? diag::ext_module_import_not_at_top_level_noop
15046 : diag::err_module_import_not_at_top_level_fatal)
15047 << M->getFullModuleName() << DC;
15048 S.Diag(cast<Decl>(DC)->getLocStart(),
15049 diag::note_module_import_not_at_top_level) << DC;
15050 } else if (!M->IsExternC && ExternCLoc.isValid()) {
15051 S.Diag(ImportLoc, diag::ext_module_import_in_extern_c)
15052 << M->getFullModuleName();
15053 S.Diag(ExternCLoc, diag::note_module_import_in_extern_c);
15057 void Sema::diagnoseMisplacedModuleImport(Module *M, SourceLocation ImportLoc) {
15058 return checkModuleImportContext(*this, M, ImportLoc, CurContext);
15061 DeclResult Sema::ActOnModuleImport(SourceLocation AtLoc,
15062 SourceLocation ImportLoc,
15063 ModuleIdPath Path) {
15065 getModuleLoader().loadModule(ImportLoc, Path, Module::AllVisible,
15066 /*IsIncludeDirective=*/false);
15070 VisibleModules.setVisible(Mod, ImportLoc);
15072 checkModuleImportContext(*this, Mod, ImportLoc, CurContext);
15074 // FIXME: we should support importing a submodule within a different submodule
15075 // of the same top-level module. Until we do, make it an error rather than
15076 // silently ignoring the import.
15077 if (Mod->getTopLevelModuleName() == getLangOpts().CurrentModule)
15078 Diag(ImportLoc, getLangOpts().CompilingModule
15079 ? diag::err_module_self_import
15080 : diag::err_module_import_in_implementation)
15081 << Mod->getFullModuleName() << getLangOpts().CurrentModule;
15083 SmallVector<SourceLocation, 2> IdentifierLocs;
15084 Module *ModCheck = Mod;
15085 for (unsigned I = 0, N = Path.size(); I != N; ++I) {
15086 // If we've run out of module parents, just drop the remaining identifiers.
15087 // We need the length to be consistent.
15090 ModCheck = ModCheck->Parent;
15092 IdentifierLocs.push_back(Path[I].second);
15095 ImportDecl *Import = ImportDecl::Create(Context,
15096 Context.getTranslationUnitDecl(),
15097 AtLoc.isValid()? AtLoc : ImportLoc,
15098 Mod, IdentifierLocs);
15099 Context.getTranslationUnitDecl()->addDecl(Import);
15103 void Sema::ActOnModuleInclude(SourceLocation DirectiveLoc, Module *Mod) {
15104 checkModuleImportContext(*this, Mod, DirectiveLoc, CurContext, true);
15106 // Determine whether we're in the #include buffer for a module. The #includes
15107 // in that buffer do not qualify as module imports; they're just an
15108 // implementation detail of us building the module.
15110 // FIXME: Should we even get ActOnModuleInclude calls for those?
15111 bool IsInModuleIncludes =
15112 TUKind == TU_Module &&
15113 getSourceManager().isWrittenInMainFile(DirectiveLoc);
15115 // Similarly, if we're in the implementation of a module, don't
15116 // synthesize an illegal module import. FIXME: Why not?
15117 bool ShouldAddImport =
15118 !IsInModuleIncludes &&
15119 (getLangOpts().CompilingModule ||
15120 getLangOpts().CurrentModule.empty() ||
15121 getLangOpts().CurrentModule != Mod->getTopLevelModuleName());
15123 // If this module import was due to an inclusion directive, create an
15124 // implicit import declaration to capture it in the AST.
15125 if (ShouldAddImport) {
15126 TranslationUnitDecl *TU = getASTContext().getTranslationUnitDecl();
15127 ImportDecl *ImportD = ImportDecl::CreateImplicit(getASTContext(), TU,
15130 TU->addDecl(ImportD);
15131 Consumer.HandleImplicitImportDecl(ImportD);
15134 getModuleLoader().makeModuleVisible(Mod, Module::AllVisible, DirectiveLoc);
15135 VisibleModules.setVisible(Mod, DirectiveLoc);
15138 void Sema::ActOnModuleBegin(SourceLocation DirectiveLoc, Module *Mod) {
15139 checkModuleImportContext(*this, Mod, DirectiveLoc, CurContext);
15141 if (getLangOpts().ModulesLocalVisibility)
15142 VisibleModulesStack.push_back(std::move(VisibleModules));
15143 VisibleModules.setVisible(Mod, DirectiveLoc);
15146 void Sema::ActOnModuleEnd(SourceLocation DirectiveLoc, Module *Mod) {
15147 checkModuleImportContext(*this, Mod, DirectiveLoc, CurContext);
15149 if (getLangOpts().ModulesLocalVisibility) {
15150 VisibleModules = std::move(VisibleModulesStack.back());
15151 VisibleModulesStack.pop_back();
15152 VisibleModules.setVisible(Mod, DirectiveLoc);
15153 // Leaving a module hides namespace names, so our visible namespace cache
15154 // is now out of date.
15155 VisibleNamespaceCache.clear();
15159 void Sema::createImplicitModuleImportForErrorRecovery(SourceLocation Loc,
15161 // Bail if we're not allowed to implicitly import a module here.
15162 if (isSFINAEContext() || !getLangOpts().ModulesErrorRecovery)
15165 // Create the implicit import declaration.
15166 TranslationUnitDecl *TU = getASTContext().getTranslationUnitDecl();
15167 ImportDecl *ImportD = ImportDecl::CreateImplicit(getASTContext(), TU,
15169 TU->addDecl(ImportD);
15170 Consumer.HandleImplicitImportDecl(ImportD);
15172 // Make the module visible.
15173 getModuleLoader().makeModuleVisible(Mod, Module::AllVisible, Loc);
15174 VisibleModules.setVisible(Mod, Loc);
15177 void Sema::ActOnPragmaRedefineExtname(IdentifierInfo* Name,
15178 IdentifierInfo* AliasName,
15179 SourceLocation PragmaLoc,
15180 SourceLocation NameLoc,
15181 SourceLocation AliasNameLoc) {
15182 NamedDecl *PrevDecl = LookupSingleName(TUScope, Name, NameLoc,
15183 LookupOrdinaryName);
15184 AsmLabelAttr *Attr =
15185 AsmLabelAttr::CreateImplicit(Context, AliasName->getName(), AliasNameLoc);
15187 // If a declaration that:
15188 // 1) declares a function or a variable
15189 // 2) has external linkage
15190 // already exists, add a label attribute to it.
15191 if (PrevDecl && (isa<FunctionDecl>(PrevDecl) || isa<VarDecl>(PrevDecl))) {
15192 if (isDeclExternC(PrevDecl))
15193 PrevDecl->addAttr(Attr);
15195 Diag(PrevDecl->getLocation(), diag::warn_redefine_extname_not_applied)
15196 << /*Variable*/(isa<FunctionDecl>(PrevDecl) ? 0 : 1) << PrevDecl;
15197 // Otherwise, add a label atttibute to ExtnameUndeclaredIdentifiers.
15199 (void)ExtnameUndeclaredIdentifiers.insert(std::make_pair(Name, Attr));
15202 void Sema::ActOnPragmaWeakID(IdentifierInfo* Name,
15203 SourceLocation PragmaLoc,
15204 SourceLocation NameLoc) {
15205 Decl *PrevDecl = LookupSingleName(TUScope, Name, NameLoc, LookupOrdinaryName);
15208 PrevDecl->addAttr(WeakAttr::CreateImplicit(Context, PragmaLoc));
15210 (void)WeakUndeclaredIdentifiers.insert(
15211 std::pair<IdentifierInfo*,WeakInfo>
15212 (Name, WeakInfo((IdentifierInfo*)nullptr, NameLoc)));
15216 void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name,
15217 IdentifierInfo* AliasName,
15218 SourceLocation PragmaLoc,
15219 SourceLocation NameLoc,
15220 SourceLocation AliasNameLoc) {
15221 Decl *PrevDecl = LookupSingleName(TUScope, AliasName, AliasNameLoc,
15222 LookupOrdinaryName);
15223 WeakInfo W = WeakInfo(Name, NameLoc);
15225 if (PrevDecl && (isa<FunctionDecl>(PrevDecl) || isa<VarDecl>(PrevDecl))) {
15226 if (!PrevDecl->hasAttr<AliasAttr>())
15227 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl))
15228 DeclApplyPragmaWeak(TUScope, ND, W);
15230 (void)WeakUndeclaredIdentifiers.insert(
15231 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W));
15235 Decl *Sema::getObjCDeclContext() const {
15236 return (dyn_cast_or_null<ObjCContainerDecl>(CurContext));
15239 AvailabilityResult Sema::getCurContextAvailability() const {
15240 const Decl *D = cast_or_null<Decl>(getCurObjCLexicalContext());
15242 return AR_Available;
15244 // If we are within an Objective-C method, we should consult
15245 // both the availability of the method as well as the
15246 // enclosing class. If the class is (say) deprecated,
15247 // the entire method is considered deprecated from the
15248 // purpose of checking if the current context is deprecated.
15249 if (const ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) {
15250 AvailabilityResult R = MD->getAvailability();
15251 if (R != AR_Available)
15253 D = MD->getClassInterface();
15255 // If we are within an Objective-c @implementation, it
15256 // gets the same availability context as the @interface.
15257 else if (const ObjCImplementationDecl *ID =
15258 dyn_cast<ObjCImplementationDecl>(D)) {
15259 D = ID->getClassInterface();
15261 // Recover from user error.
15262 return D ? D->getAvailability() : AR_Available;