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_wchar_t:
113 case tok::kw___underlying_type:
114 case tok::kw___auto_type:
117 case tok::annot_typename:
118 case tok::kw_char16_t:
119 case tok::kw_char32_t:
121 case tok::annot_decltype:
122 case tok::kw_decltype:
123 return getLangOpts().CPlusPlus;
133 enum class UnqualifiedTypeNameLookupResult {
138 } // end anonymous namespace
140 /// \brief Tries to perform unqualified lookup of the type decls in bases for
142 /// \return \a NotFound if no any decls is found, \a FoundNotType if found not a
143 /// type decl, \a FoundType if only type decls are found.
144 static UnqualifiedTypeNameLookupResult
145 lookupUnqualifiedTypeNameInBase(Sema &S, const IdentifierInfo &II,
146 SourceLocation NameLoc,
147 const CXXRecordDecl *RD) {
148 if (!RD->hasDefinition())
149 return UnqualifiedTypeNameLookupResult::NotFound;
150 // Look for type decls in base classes.
151 UnqualifiedTypeNameLookupResult FoundTypeDecl =
152 UnqualifiedTypeNameLookupResult::NotFound;
153 for (const auto &Base : RD->bases()) {
154 const CXXRecordDecl *BaseRD = nullptr;
155 if (auto *BaseTT = Base.getType()->getAs<TagType>())
156 BaseRD = BaseTT->getAsCXXRecordDecl();
157 else if (auto *TST = Base.getType()->getAs<TemplateSpecializationType>()) {
158 // Look for type decls in dependent base classes that have known primary
160 if (!TST || !TST->isDependentType())
162 auto *TD = TST->getTemplateName().getAsTemplateDecl();
165 auto *BasePrimaryTemplate =
166 dyn_cast_or_null<CXXRecordDecl>(TD->getTemplatedDecl());
167 if (!BasePrimaryTemplate)
169 BaseRD = BasePrimaryTemplate;
172 for (NamedDecl *ND : BaseRD->lookup(&II)) {
173 if (!isa<TypeDecl>(ND))
174 return UnqualifiedTypeNameLookupResult::FoundNonType;
175 FoundTypeDecl = UnqualifiedTypeNameLookupResult::FoundType;
177 if (FoundTypeDecl == UnqualifiedTypeNameLookupResult::NotFound) {
178 switch (lookupUnqualifiedTypeNameInBase(S, II, NameLoc, BaseRD)) {
179 case UnqualifiedTypeNameLookupResult::FoundNonType:
180 return UnqualifiedTypeNameLookupResult::FoundNonType;
181 case UnqualifiedTypeNameLookupResult::FoundType:
182 FoundTypeDecl = UnqualifiedTypeNameLookupResult::FoundType;
184 case UnqualifiedTypeNameLookupResult::NotFound:
191 return FoundTypeDecl;
194 static ParsedType recoverFromTypeInKnownDependentBase(Sema &S,
195 const IdentifierInfo &II,
196 SourceLocation NameLoc) {
197 // Lookup in the parent class template context, if any.
198 const CXXRecordDecl *RD = nullptr;
199 UnqualifiedTypeNameLookupResult FoundTypeDecl =
200 UnqualifiedTypeNameLookupResult::NotFound;
201 for (DeclContext *DC = S.CurContext;
202 DC && FoundTypeDecl == UnqualifiedTypeNameLookupResult::NotFound;
203 DC = DC->getParent()) {
204 // Look for type decls in dependent base classes that have known primary
206 RD = dyn_cast<CXXRecordDecl>(DC);
207 if (RD && RD->getDescribedClassTemplate())
208 FoundTypeDecl = lookupUnqualifiedTypeNameInBase(S, II, NameLoc, RD);
210 if (FoundTypeDecl != UnqualifiedTypeNameLookupResult::FoundType)
213 // We found some types in dependent base classes. Recover as if the user
214 // wrote 'typename MyClass::II' instead of 'II'. We'll fully resolve the
215 // lookup during template instantiation.
216 S.Diag(NameLoc, diag::ext_found_via_dependent_bases_lookup) << &II;
218 ASTContext &Context = S.Context;
219 auto *NNS = NestedNameSpecifier::Create(Context, nullptr, false,
220 cast<Type>(Context.getRecordType(RD)));
221 QualType T = Context.getDependentNameType(ETK_Typename, NNS, &II);
224 SS.MakeTrivial(Context, NNS, SourceRange(NameLoc));
226 TypeLocBuilder Builder;
227 DependentNameTypeLoc DepTL = Builder.push<DependentNameTypeLoc>(T);
228 DepTL.setNameLoc(NameLoc);
229 DepTL.setElaboratedKeywordLoc(SourceLocation());
230 DepTL.setQualifierLoc(SS.getWithLocInContext(Context));
231 return S.CreateParsedType(T, Builder.getTypeSourceInfo(Context, T));
234 /// \brief If the identifier refers to a type name within this scope,
235 /// return the declaration of that type.
237 /// This routine performs ordinary name lookup of the identifier II
238 /// within the given scope, with optional C++ scope specifier SS, to
239 /// determine whether the name refers to a type. If so, returns an
240 /// opaque pointer (actually a QualType) corresponding to that
241 /// type. Otherwise, returns NULL.
242 ParsedType Sema::getTypeName(const IdentifierInfo &II, SourceLocation NameLoc,
243 Scope *S, CXXScopeSpec *SS,
244 bool isClassName, bool HasTrailingDot,
245 ParsedType ObjectTypePtr,
246 bool IsCtorOrDtorName,
247 bool WantNontrivialTypeSourceInfo,
248 IdentifierInfo **CorrectedII) {
249 // Determine where we will perform name lookup.
250 DeclContext *LookupCtx = nullptr;
252 QualType ObjectType = ObjectTypePtr.get();
253 if (ObjectType->isRecordType())
254 LookupCtx = computeDeclContext(ObjectType);
255 } else if (SS && SS->isNotEmpty()) {
256 LookupCtx = computeDeclContext(*SS, false);
259 if (isDependentScopeSpecifier(*SS)) {
261 // A qualified-id that refers to a type and in which the
262 // nested-name-specifier depends on a template-parameter (14.6.2)
263 // shall be prefixed by the keyword typename to indicate that the
264 // qualified-id denotes a type, forming an
265 // elaborated-type-specifier (7.1.5.3).
267 // We therefore do not perform any name lookup if the result would
268 // refer to a member of an unknown specialization.
269 if (!isClassName && !IsCtorOrDtorName)
272 // We know from the grammar that this name refers to a type,
273 // so build a dependent node to describe the type.
274 if (WantNontrivialTypeSourceInfo)
275 return ActOnTypenameType(S, SourceLocation(), *SS, II, NameLoc).get();
277 NestedNameSpecifierLoc QualifierLoc = SS->getWithLocInContext(Context);
278 QualType T = CheckTypenameType(ETK_None, SourceLocation(), QualifierLoc,
280 return ParsedType::make(T);
286 if (!LookupCtx->isDependentContext() &&
287 RequireCompleteDeclContext(*SS, LookupCtx))
291 // FIXME: LookupNestedNameSpecifierName isn't the right kind of
292 // lookup for class-names.
293 LookupNameKind Kind = isClassName ? LookupNestedNameSpecifierName :
295 LookupResult Result(*this, &II, NameLoc, Kind);
297 // Perform "qualified" name lookup into the declaration context we
298 // computed, which is either the type of the base of a member access
299 // expression or the declaration context associated with a prior
300 // nested-name-specifier.
301 LookupQualifiedName(Result, LookupCtx);
303 if (ObjectTypePtr && Result.empty()) {
304 // C++ [basic.lookup.classref]p3:
305 // If the unqualified-id is ~type-name, the type-name is looked up
306 // in the context of the entire postfix-expression. If the type T of
307 // the object expression is of a class type C, the type-name is also
308 // looked up in the scope of class C. At least one of the lookups shall
309 // find a name that refers to (possibly cv-qualified) T.
310 LookupName(Result, S);
313 // Perform unqualified name lookup.
314 LookupName(Result, S);
316 // For unqualified lookup in a class template in MSVC mode, look into
317 // dependent base classes where the primary class template is known.
318 if (Result.empty() && getLangOpts().MSVCCompat && (!SS || SS->isEmpty())) {
319 if (ParsedType TypeInBase =
320 recoverFromTypeInKnownDependentBase(*this, II, NameLoc))
325 NamedDecl *IIDecl = nullptr;
326 switch (Result.getResultKind()) {
327 case LookupResult::NotFound:
328 case LookupResult::NotFoundInCurrentInstantiation:
330 TypoCorrection Correction = CorrectTypo(
331 Result.getLookupNameInfo(), Kind, S, SS,
332 llvm::make_unique<TypeNameValidatorCCC>(true, isClassName),
334 IdentifierInfo *NewII = Correction.getCorrectionAsIdentifierInfo();
336 bool MemberOfUnknownSpecialization;
337 UnqualifiedId TemplateName;
338 TemplateName.setIdentifier(NewII, NameLoc);
339 NestedNameSpecifier *NNS = Correction.getCorrectionSpecifier();
340 CXXScopeSpec NewSS, *NewSSPtr = SS;
342 NewSS.MakeTrivial(Context, NNS, SourceRange(NameLoc));
345 if (Correction && (NNS || NewII != &II) &&
346 // Ignore a correction to a template type as the to-be-corrected
347 // identifier is not a template (typo correction for template names
348 // is handled elsewhere).
349 !(getLangOpts().CPlusPlus && NewSSPtr &&
350 isTemplateName(S, *NewSSPtr, false, TemplateName, nullptr, false,
351 Template, MemberOfUnknownSpecialization))) {
352 ParsedType Ty = getTypeName(*NewII, NameLoc, S, NewSSPtr,
353 isClassName, HasTrailingDot, ObjectTypePtr,
355 WantNontrivialTypeSourceInfo);
357 diagnoseTypo(Correction,
358 PDiag(diag::err_unknown_type_or_class_name_suggest)
359 << Result.getLookupName() << isClassName);
361 SS->MakeTrivial(Context, NNS, SourceRange(NameLoc));
362 *CorrectedII = NewII;
367 // If typo correction failed or was not performed, fall through
368 case LookupResult::FoundOverloaded:
369 case LookupResult::FoundUnresolvedValue:
370 Result.suppressDiagnostics();
373 case LookupResult::Ambiguous:
374 // Recover from type-hiding ambiguities by hiding the type. We'll
375 // do the lookup again when looking for an object, and we can
376 // diagnose the error then. If we don't do this, then the error
377 // about hiding the type will be immediately followed by an error
378 // that only makes sense if the identifier was treated like a type.
379 if (Result.getAmbiguityKind() == LookupResult::AmbiguousTagHiding) {
380 Result.suppressDiagnostics();
384 // Look to see if we have a type anywhere in the list of results.
385 for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end();
386 Res != ResEnd; ++Res) {
387 if (isa<TypeDecl>(*Res) || isa<ObjCInterfaceDecl>(*Res)) {
389 (*Res)->getLocation().getRawEncoding() <
390 IIDecl->getLocation().getRawEncoding())
396 // None of the entities we found is a type, so there is no way
397 // to even assume that the result is a type. In this case, don't
398 // complain about the ambiguity. The parser will either try to
399 // perform this lookup again (e.g., as an object name), which
400 // will produce the ambiguity, or will complain that it expected
402 Result.suppressDiagnostics();
406 // We found a type within the ambiguous lookup; diagnose the
407 // ambiguity and then return that type. This might be the right
408 // answer, or it might not be, but it suppresses any attempt to
409 // perform the name lookup again.
412 case LookupResult::Found:
413 IIDecl = Result.getFoundDecl();
417 assert(IIDecl && "Didn't find decl");
420 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) {
421 DiagnoseUseOfDecl(IIDecl, NameLoc);
423 T = Context.getTypeDeclType(TD);
424 MarkAnyDeclReferenced(TD->getLocation(), TD, /*OdrUse=*/false);
426 // NOTE: avoid constructing an ElaboratedType(Loc) if this is a
427 // constructor or destructor name (in such a case, the scope specifier
428 // will be attached to the enclosing Expr or Decl node).
429 if (SS && SS->isNotEmpty() && !IsCtorOrDtorName) {
430 if (WantNontrivialTypeSourceInfo) {
431 // Construct a type with type-source information.
432 TypeLocBuilder Builder;
433 Builder.pushTypeSpec(T).setNameLoc(NameLoc);
435 T = getElaboratedType(ETK_None, *SS, T);
436 ElaboratedTypeLoc ElabTL = Builder.push<ElaboratedTypeLoc>(T);
437 ElabTL.setElaboratedKeywordLoc(SourceLocation());
438 ElabTL.setQualifierLoc(SS->getWithLocInContext(Context));
439 return CreateParsedType(T, Builder.getTypeSourceInfo(Context, T));
441 T = getElaboratedType(ETK_None, *SS, T);
444 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) {
445 (void)DiagnoseUseOfDecl(IDecl, NameLoc);
447 T = Context.getObjCInterfaceType(IDecl);
451 // If it's not plausibly a type, suppress diagnostics.
452 Result.suppressDiagnostics();
455 return ParsedType::make(T);
458 // Builds a fake NNS for the given decl context.
459 static NestedNameSpecifier *
460 synthesizeCurrentNestedNameSpecifier(ASTContext &Context, DeclContext *DC) {
461 for (;; DC = DC->getLookupParent()) {
462 DC = DC->getPrimaryContext();
463 auto *ND = dyn_cast<NamespaceDecl>(DC);
464 if (ND && !ND->isInline() && !ND->isAnonymousNamespace())
465 return NestedNameSpecifier::Create(Context, nullptr, ND);
466 else if (auto *RD = dyn_cast<CXXRecordDecl>(DC))
467 return NestedNameSpecifier::Create(Context, nullptr, RD->isTemplateDecl(),
468 RD->getTypeForDecl());
469 else if (isa<TranslationUnitDecl>(DC))
470 return NestedNameSpecifier::GlobalSpecifier(Context);
472 llvm_unreachable("something isn't in TU scope?");
475 ParsedType Sema::ActOnDelayedDefaultTemplateArg(const IdentifierInfo &II,
476 SourceLocation NameLoc) {
477 // Accepting an undeclared identifier as a default argument for a template
478 // type parameter is a Microsoft extension.
479 Diag(NameLoc, diag::ext_ms_delayed_template_argument) << &II;
481 // Build a fake DependentNameType that will perform lookup into CurContext at
482 // instantiation time. The name specifier isn't dependent, so template
483 // instantiation won't transform it. It will retry the lookup, however.
484 NestedNameSpecifier *NNS =
485 synthesizeCurrentNestedNameSpecifier(Context, CurContext);
486 QualType T = Context.getDependentNameType(ETK_None, NNS, &II);
488 // Build type location information. We synthesized the qualifier, so we have
489 // to build a fake NestedNameSpecifierLoc.
490 NestedNameSpecifierLocBuilder NNSLocBuilder;
491 NNSLocBuilder.MakeTrivial(Context, NNS, SourceRange(NameLoc));
492 NestedNameSpecifierLoc QualifierLoc = NNSLocBuilder.getWithLocInContext(Context);
494 TypeLocBuilder Builder;
495 DependentNameTypeLoc DepTL = Builder.push<DependentNameTypeLoc>(T);
496 DepTL.setNameLoc(NameLoc);
497 DepTL.setElaboratedKeywordLoc(SourceLocation());
498 DepTL.setQualifierLoc(QualifierLoc);
499 return CreateParsedType(T, Builder.getTypeSourceInfo(Context, T));
502 /// isTagName() - This method is called *for error recovery purposes only*
503 /// to determine if the specified name is a valid tag name ("struct foo"). If
504 /// so, this returns the TST for the tag corresponding to it (TST_enum,
505 /// TST_union, TST_struct, TST_interface, TST_class). This is used to diagnose
506 /// cases in C where the user forgot to specify the tag.
507 DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) {
508 // Do a tag name lookup in this scope.
509 LookupResult R(*this, &II, SourceLocation(), LookupTagName);
510 LookupName(R, S, false);
511 R.suppressDiagnostics();
512 if (R.getResultKind() == LookupResult::Found)
513 if (const TagDecl *TD = R.getAsSingle<TagDecl>()) {
514 switch (TD->getTagKind()) {
515 case TTK_Struct: return DeclSpec::TST_struct;
516 case TTK_Interface: return DeclSpec::TST_interface;
517 case TTK_Union: return DeclSpec::TST_union;
518 case TTK_Class: return DeclSpec::TST_class;
519 case TTK_Enum: return DeclSpec::TST_enum;
523 return DeclSpec::TST_unspecified;
526 /// isMicrosoftMissingTypename - In Microsoft mode, within class scope,
527 /// if a CXXScopeSpec's type is equal to the type of one of the base classes
528 /// then downgrade the missing typename error to a warning.
529 /// This is needed for MSVC compatibility; Example:
531 /// template<class T> class A {
533 /// typedef int TYPE;
535 /// template<class T> class B : public A<T> {
537 /// A<T>::TYPE a; // no typename required because A<T> is a base class.
540 bool Sema::isMicrosoftMissingTypename(const CXXScopeSpec *SS, Scope *S) {
541 if (CurContext->isRecord()) {
542 if (SS->getScopeRep()->getKind() == NestedNameSpecifier::Super)
545 const Type *Ty = SS->getScopeRep()->getAsType();
547 CXXRecordDecl *RD = cast<CXXRecordDecl>(CurContext);
548 for (const auto &Base : RD->bases())
549 if (Context.hasSameUnqualifiedType(QualType(Ty, 1), Base.getType()))
551 return S->isFunctionPrototypeScope();
553 return CurContext->isFunctionOrMethod() || S->isFunctionPrototypeScope();
556 void Sema::DiagnoseUnknownTypeName(IdentifierInfo *&II,
557 SourceLocation IILoc,
560 ParsedType &SuggestedType,
561 bool AllowClassTemplates) {
562 // We don't have anything to suggest (yet).
563 SuggestedType = nullptr;
565 // There may have been a typo in the name of the type. Look up typo
566 // results, in case we have something that we can suggest.
567 if (TypoCorrection Corrected =
568 CorrectTypo(DeclarationNameInfo(II, IILoc), LookupOrdinaryName, S, SS,
569 llvm::make_unique<TypeNameValidatorCCC>(
570 false, false, AllowClassTemplates),
571 CTK_ErrorRecovery)) {
572 if (Corrected.isKeyword()) {
573 // We corrected to a keyword.
574 diagnoseTypo(Corrected, PDiag(diag::err_unknown_typename_suggest) << II);
575 II = Corrected.getCorrectionAsIdentifierInfo();
577 // We found a similarly-named type or interface; suggest that.
578 if (!SS || !SS->isSet()) {
579 diagnoseTypo(Corrected,
580 PDiag(diag::err_unknown_typename_suggest) << II);
581 } else if (DeclContext *DC = computeDeclContext(*SS, false)) {
582 std::string CorrectedStr(Corrected.getAsString(getLangOpts()));
583 bool DroppedSpecifier = Corrected.WillReplaceSpecifier() &&
584 II->getName().equals(CorrectedStr);
585 diagnoseTypo(Corrected,
586 PDiag(diag::err_unknown_nested_typename_suggest)
587 << II << DC << DroppedSpecifier << SS->getRange());
589 llvm_unreachable("could not have corrected a typo here");
593 if (Corrected.getCorrectionSpecifier())
594 tmpSS.MakeTrivial(Context, Corrected.getCorrectionSpecifier(),
597 getTypeName(*Corrected.getCorrectionAsIdentifierInfo(), IILoc, S,
598 tmpSS.isSet() ? &tmpSS : SS, false, false, nullptr,
599 /*IsCtorOrDtorName=*/false,
600 /*NonTrivialTypeSourceInfo=*/true);
605 if (getLangOpts().CPlusPlus) {
606 // See if II is a class template that the user forgot to pass arguments to.
608 Name.setIdentifier(II, IILoc);
609 CXXScopeSpec EmptySS;
610 TemplateTy TemplateResult;
611 bool MemberOfUnknownSpecialization;
612 if (isTemplateName(S, SS ? *SS : EmptySS, /*hasTemplateKeyword=*/false,
613 Name, nullptr, true, TemplateResult,
614 MemberOfUnknownSpecialization) == TNK_Type_template) {
615 TemplateName TplName = TemplateResult.get();
616 Diag(IILoc, diag::err_template_missing_args) << TplName;
617 if (TemplateDecl *TplDecl = TplName.getAsTemplateDecl()) {
618 Diag(TplDecl->getLocation(), diag::note_template_decl_here)
619 << TplDecl->getTemplateParameters()->getSourceRange();
625 // FIXME: Should we move the logic that tries to recover from a missing tag
626 // (struct, union, enum) from Parser::ParseImplicitInt here, instead?
628 if (!SS || (!SS->isSet() && !SS->isInvalid()))
629 Diag(IILoc, diag::err_unknown_typename) << II;
630 else if (DeclContext *DC = computeDeclContext(*SS, false))
631 Diag(IILoc, diag::err_typename_nested_not_found)
632 << II << DC << SS->getRange();
633 else if (isDependentScopeSpecifier(*SS)) {
634 unsigned DiagID = diag::err_typename_missing;
635 if (getLangOpts().MSVCCompat && isMicrosoftMissingTypename(SS, S))
636 DiagID = diag::ext_typename_missing;
638 Diag(SS->getRange().getBegin(), DiagID)
639 << SS->getScopeRep() << II->getName()
640 << SourceRange(SS->getRange().getBegin(), IILoc)
641 << FixItHint::CreateInsertion(SS->getRange().getBegin(), "typename ");
642 SuggestedType = ActOnTypenameType(S, SourceLocation(),
643 *SS, *II, IILoc).get();
645 assert(SS && SS->isInvalid() &&
646 "Invalid scope specifier has already been diagnosed");
650 /// \brief Determine whether the given result set contains either a type name
652 static bool isResultTypeOrTemplate(LookupResult &R, const Token &NextToken) {
653 bool CheckTemplate = R.getSema().getLangOpts().CPlusPlus &&
654 NextToken.is(tok::less);
656 for (LookupResult::iterator I = R.begin(), IEnd = R.end(); I != IEnd; ++I) {
657 if (isa<TypeDecl>(*I) || isa<ObjCInterfaceDecl>(*I))
660 if (CheckTemplate && isa<TemplateDecl>(*I))
667 static bool isTagTypeWithMissingTag(Sema &SemaRef, LookupResult &Result,
668 Scope *S, CXXScopeSpec &SS,
669 IdentifierInfo *&Name,
670 SourceLocation NameLoc) {
671 LookupResult R(SemaRef, Name, NameLoc, Sema::LookupTagName);
672 SemaRef.LookupParsedName(R, S, &SS);
673 if (TagDecl *Tag = R.getAsSingle<TagDecl>()) {
674 StringRef FixItTagName;
675 switch (Tag->getTagKind()) {
677 FixItTagName = "class ";
681 FixItTagName = "enum ";
685 FixItTagName = "struct ";
689 FixItTagName = "__interface ";
693 FixItTagName = "union ";
697 StringRef TagName = FixItTagName.drop_back();
698 SemaRef.Diag(NameLoc, diag::err_use_of_tag_name_without_tag)
699 << Name << TagName << SemaRef.getLangOpts().CPlusPlus
700 << FixItHint::CreateInsertion(NameLoc, FixItTagName);
702 for (LookupResult::iterator I = Result.begin(), IEnd = Result.end();
704 SemaRef.Diag((*I)->getLocation(), diag::note_decl_hiding_tag_type)
707 // Replace lookup results with just the tag decl.
708 Result.clear(Sema::LookupTagName);
709 SemaRef.LookupParsedName(Result, S, &SS);
716 /// Build a ParsedType for a simple-type-specifier with a nested-name-specifier.
717 static ParsedType buildNestedType(Sema &S, CXXScopeSpec &SS,
718 QualType T, SourceLocation NameLoc) {
719 ASTContext &Context = S.Context;
721 TypeLocBuilder Builder;
722 Builder.pushTypeSpec(T).setNameLoc(NameLoc);
724 T = S.getElaboratedType(ETK_None, SS, T);
725 ElaboratedTypeLoc ElabTL = Builder.push<ElaboratedTypeLoc>(T);
726 ElabTL.setElaboratedKeywordLoc(SourceLocation());
727 ElabTL.setQualifierLoc(SS.getWithLocInContext(Context));
728 return S.CreateParsedType(T, Builder.getTypeSourceInfo(Context, T));
731 Sema::NameClassification
732 Sema::ClassifyName(Scope *S, CXXScopeSpec &SS, IdentifierInfo *&Name,
733 SourceLocation NameLoc, const Token &NextToken,
734 bool IsAddressOfOperand,
735 std::unique_ptr<CorrectionCandidateCallback> CCC) {
736 DeclarationNameInfo NameInfo(Name, NameLoc);
737 ObjCMethodDecl *CurMethod = getCurMethodDecl();
739 if (NextToken.is(tok::coloncolon)) {
740 BuildCXXNestedNameSpecifier(S, *Name, NameLoc, NextToken.getLocation(),
741 QualType(), false, SS, nullptr, false);
744 LookupResult Result(*this, Name, NameLoc, LookupOrdinaryName);
745 LookupParsedName(Result, S, &SS, !CurMethod);
747 // For unqualified lookup in a class template in MSVC mode, look into
748 // dependent base classes where the primary class template is known.
749 if (Result.empty() && SS.isEmpty() && getLangOpts().MSVCCompat) {
750 if (ParsedType TypeInBase =
751 recoverFromTypeInKnownDependentBase(*this, *Name, NameLoc))
755 // Perform lookup for Objective-C instance variables (including automatically
756 // synthesized instance variables), if we're in an Objective-C method.
757 // FIXME: This lookup really, really needs to be folded in to the normal
758 // unqualified lookup mechanism.
759 if (!SS.isSet() && CurMethod && !isResultTypeOrTemplate(Result, NextToken)) {
760 ExprResult E = LookupInObjCMethod(Result, S, Name, true);
761 if (E.get() || E.isInvalid())
765 bool SecondTry = false;
766 bool IsFilteredTemplateName = false;
769 switch (Result.getResultKind()) {
770 case LookupResult::NotFound:
771 // If an unqualified-id is followed by a '(', then we have a function
773 if (!SS.isSet() && NextToken.is(tok::l_paren)) {
774 // In C++, this is an ADL-only call.
776 if (getLangOpts().CPlusPlus)
777 return BuildDeclarationNameExpr(SS, Result, /*ADL=*/true);
780 // If the expression that precedes the parenthesized argument list in a
781 // function call consists solely of an identifier, and if no
782 // declaration is visible for this identifier, the identifier is
783 // implicitly declared exactly as if, in the innermost block containing
784 // the function call, the declaration
786 // extern int identifier ();
790 // We also allow this in C99 as an extension.
791 if (NamedDecl *D = ImplicitlyDefineFunction(NameLoc, *Name, S)) {
793 Result.resolveKind();
794 return BuildDeclarationNameExpr(SS, Result, /*ADL=*/false);
798 // In C, we first see whether there is a tag type by the same name, in
799 // which case it's likely that the user just forgot to write "enum",
800 // "struct", or "union".
801 if (!getLangOpts().CPlusPlus && !SecondTry &&
802 isTagTypeWithMissingTag(*this, Result, S, SS, Name, NameLoc)) {
806 // Perform typo correction to determine if there is another name that is
807 // close to this name.
808 if (!SecondTry && CCC) {
810 if (TypoCorrection Corrected = CorrectTypo(Result.getLookupNameInfo(),
811 Result.getLookupKind(), S,
813 CTK_ErrorRecovery)) {
814 unsigned UnqualifiedDiag = diag::err_undeclared_var_use_suggest;
815 unsigned QualifiedDiag = diag::err_no_member_suggest;
817 NamedDecl *FirstDecl = Corrected.getFoundDecl();
818 NamedDecl *UnderlyingFirstDecl = Corrected.getCorrectionDecl();
819 if (getLangOpts().CPlusPlus && NextToken.is(tok::less) &&
820 UnderlyingFirstDecl && isa<TemplateDecl>(UnderlyingFirstDecl)) {
821 UnqualifiedDiag = diag::err_no_template_suggest;
822 QualifiedDiag = diag::err_no_member_template_suggest;
823 } else if (UnderlyingFirstDecl &&
824 (isa<TypeDecl>(UnderlyingFirstDecl) ||
825 isa<ObjCInterfaceDecl>(UnderlyingFirstDecl) ||
826 isa<ObjCCompatibleAliasDecl>(UnderlyingFirstDecl))) {
827 UnqualifiedDiag = diag::err_unknown_typename_suggest;
828 QualifiedDiag = diag::err_unknown_nested_typename_suggest;
832 diagnoseTypo(Corrected, PDiag(UnqualifiedDiag) << Name);
833 } else {// FIXME: is this even reachable? Test it.
834 std::string CorrectedStr(Corrected.getAsString(getLangOpts()));
835 bool DroppedSpecifier = Corrected.WillReplaceSpecifier() &&
836 Name->getName().equals(CorrectedStr);
837 diagnoseTypo(Corrected, PDiag(QualifiedDiag)
838 << Name << computeDeclContext(SS, false)
839 << DroppedSpecifier << SS.getRange());
842 // Update the name, so that the caller has the new name.
843 Name = Corrected.getCorrectionAsIdentifierInfo();
845 // Typo correction corrected to a keyword.
846 if (Corrected.isKeyword())
849 // Also update the LookupResult...
850 // FIXME: This should probably go away at some point
852 Result.setLookupName(Corrected.getCorrection());
854 Result.addDecl(FirstDecl);
856 // If we found an Objective-C instance variable, let
857 // LookupInObjCMethod build the appropriate expression to
858 // reference the ivar.
859 // FIXME: This is a gross hack.
860 if (ObjCIvarDecl *Ivar = Result.getAsSingle<ObjCIvarDecl>()) {
862 ExprResult E(LookupInObjCMethod(Result, S, Ivar->getIdentifier()));
870 // We failed to correct; just fall through and let the parser deal with it.
871 Result.suppressDiagnostics();
872 return NameClassification::Unknown();
874 case LookupResult::NotFoundInCurrentInstantiation: {
875 // We performed name lookup into the current instantiation, and there were
876 // dependent bases, so we treat this result the same way as any other
877 // dependent nested-name-specifier.
880 // A name used in a template declaration or definition and that is
881 // dependent on a template-parameter is assumed not to name a type
882 // unless the applicable name lookup finds a type name or the name is
883 // qualified by the keyword typename.
885 // FIXME: If the next token is '<', we might want to ask the parser to
886 // perform some heroics to see if we actually have a
887 // template-argument-list, which would indicate a missing 'template'
889 return ActOnDependentIdExpression(SS, /*TemplateKWLoc=*/SourceLocation(),
890 NameInfo, IsAddressOfOperand,
891 /*TemplateArgs=*/nullptr);
894 case LookupResult::Found:
895 case LookupResult::FoundOverloaded:
896 case LookupResult::FoundUnresolvedValue:
899 case LookupResult::Ambiguous:
900 if (getLangOpts().CPlusPlus && NextToken.is(tok::less) &&
901 hasAnyAcceptableTemplateNames(Result)) {
902 // C++ [temp.local]p3:
903 // A lookup that finds an injected-class-name (10.2) can result in an
904 // ambiguity in certain cases (for example, if it is found in more than
905 // one base class). If all of the injected-class-names that are found
906 // refer to specializations of the same class template, and if the name
907 // is followed by a template-argument-list, the reference refers to the
908 // class template itself and not a specialization thereof, and is not
911 // This filtering can make an ambiguous result into an unambiguous one,
912 // so try again after filtering out template names.
913 FilterAcceptableTemplateNames(Result);
914 if (!Result.isAmbiguous()) {
915 IsFilteredTemplateName = true;
920 // Diagnose the ambiguity and return an error.
921 return NameClassification::Error();
924 if (getLangOpts().CPlusPlus && NextToken.is(tok::less) &&
925 (IsFilteredTemplateName || hasAnyAcceptableTemplateNames(Result))) {
926 // C++ [temp.names]p3:
927 // After name lookup (3.4) finds that a name is a template-name or that
928 // an operator-function-id or a literal- operator-id refers to a set of
929 // overloaded functions any member of which is a function template if
930 // this is followed by a <, the < is always taken as the delimiter of a
931 // template-argument-list and never as the less-than operator.
932 if (!IsFilteredTemplateName)
933 FilterAcceptableTemplateNames(Result);
935 if (!Result.empty()) {
936 bool IsFunctionTemplate;
938 TemplateName Template;
939 if (Result.end() - Result.begin() > 1) {
940 IsFunctionTemplate = true;
941 Template = Context.getOverloadedTemplateName(Result.begin(),
945 = cast<TemplateDecl>((*Result.begin())->getUnderlyingDecl());
946 IsFunctionTemplate = isa<FunctionTemplateDecl>(TD);
947 IsVarTemplate = isa<VarTemplateDecl>(TD);
949 if (SS.isSet() && !SS.isInvalid())
950 Template = Context.getQualifiedTemplateName(SS.getScopeRep(),
951 /*TemplateKeyword=*/false,
954 Template = TemplateName(TD);
957 if (IsFunctionTemplate) {
958 // Function templates always go through overload resolution, at which
959 // point we'll perform the various checks (e.g., accessibility) we need
960 // to based on which function we selected.
961 Result.suppressDiagnostics();
963 return NameClassification::FunctionTemplate(Template);
966 return IsVarTemplate ? NameClassification::VarTemplate(Template)
967 : NameClassification::TypeTemplate(Template);
971 NamedDecl *FirstDecl = (*Result.begin())->getUnderlyingDecl();
972 if (TypeDecl *Type = dyn_cast<TypeDecl>(FirstDecl)) {
973 DiagnoseUseOfDecl(Type, NameLoc);
974 MarkAnyDeclReferenced(Type->getLocation(), Type, /*OdrUse=*/false);
975 QualType T = Context.getTypeDeclType(Type);
977 return buildNestedType(*this, SS, T, NameLoc);
978 return ParsedType::make(T);
981 ObjCInterfaceDecl *Class = dyn_cast<ObjCInterfaceDecl>(FirstDecl);
983 // FIXME: It's unfortunate that we don't have a Type node for handling this.
984 if (ObjCCompatibleAliasDecl *Alias =
985 dyn_cast<ObjCCompatibleAliasDecl>(FirstDecl))
986 Class = Alias->getClassInterface();
990 DiagnoseUseOfDecl(Class, NameLoc);
992 if (NextToken.is(tok::period)) {
993 // Interface. <something> is parsed as a property reference expression.
994 // Just return "unknown" as a fall-through for now.
995 Result.suppressDiagnostics();
996 return NameClassification::Unknown();
999 QualType T = Context.getObjCInterfaceType(Class);
1000 return ParsedType::make(T);
1003 // We can have a type template here if we're classifying a template argument.
1004 if (isa<TemplateDecl>(FirstDecl) && !isa<FunctionTemplateDecl>(FirstDecl))
1005 return NameClassification::TypeTemplate(
1006 TemplateName(cast<TemplateDecl>(FirstDecl)));
1008 // Check for a tag type hidden by a non-type decl in a few cases where it
1009 // seems likely a type is wanted instead of the non-type that was found.
1010 bool NextIsOp = NextToken.isOneOf(tok::amp, tok::star);
1011 if ((NextToken.is(tok::identifier) ||
1013 FirstDecl->getUnderlyingDecl()->isFunctionOrFunctionTemplate())) &&
1014 isTagTypeWithMissingTag(*this, Result, S, SS, Name, NameLoc)) {
1015 TypeDecl *Type = Result.getAsSingle<TypeDecl>();
1016 DiagnoseUseOfDecl(Type, NameLoc);
1017 QualType T = Context.getTypeDeclType(Type);
1018 if (SS.isNotEmpty())
1019 return buildNestedType(*this, SS, T, NameLoc);
1020 return ParsedType::make(T);
1023 if (FirstDecl->isCXXClassMember())
1024 return BuildPossibleImplicitMemberExpr(SS, SourceLocation(), Result,
1027 bool ADL = UseArgumentDependentLookup(SS, Result, NextToken.is(tok::l_paren));
1028 return BuildDeclarationNameExpr(SS, Result, ADL);
1031 // Determines the context to return to after temporarily entering a
1032 // context. This depends in an unnecessarily complicated way on the
1033 // exact ordering of callbacks from the parser.
1034 DeclContext *Sema::getContainingDC(DeclContext *DC) {
1036 // Functions defined inline within classes aren't parsed until we've
1037 // finished parsing the top-level class, so the top-level class is
1038 // the context we'll need to return to.
1039 // A Lambda call operator whose parent is a class must not be treated
1040 // as an inline member function. A Lambda can be used legally
1041 // either as an in-class member initializer or a default argument. These
1042 // are parsed once the class has been marked complete and so the containing
1043 // context would be the nested class (when the lambda is defined in one);
1044 // If the class is not complete, then the lambda is being used in an
1045 // ill-formed fashion (such as to specify the width of a bit-field, or
1046 // in an array-bound) - in which case we still want to return the
1047 // lexically containing DC (which could be a nested class).
1048 if (isa<FunctionDecl>(DC) && !isLambdaCallOperator(DC)) {
1049 DC = DC->getLexicalParent();
1051 // A function not defined within a class will always return to its
1053 if (!isa<CXXRecordDecl>(DC))
1056 // A C++ inline method/friend is parsed *after* the topmost class
1057 // it was declared in is fully parsed ("complete"); the topmost
1058 // class is the context we need to return to.
1059 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent()))
1062 // Return the declaration context of the topmost class the inline method is
1067 return DC->getLexicalParent();
1070 void Sema::PushDeclContext(Scope *S, DeclContext *DC) {
1071 assert(getContainingDC(DC) == CurContext &&
1072 "The next DeclContext should be lexically contained in the current one.");
1077 void Sema::PopDeclContext() {
1078 assert(CurContext && "DeclContext imbalance!");
1080 CurContext = getContainingDC(CurContext);
1081 assert(CurContext && "Popped translation unit!");
1084 Sema::SkippedDefinitionContext Sema::ActOnTagStartSkippedDefinition(Scope *S,
1086 // Unlike PushDeclContext, the context to which we return is not necessarily
1087 // the containing DC of TD, because the new context will be some pre-existing
1088 // TagDecl definition instead of a fresh one.
1089 auto Result = static_cast<SkippedDefinitionContext>(CurContext);
1090 CurContext = cast<TagDecl>(D)->getDefinition();
1091 assert(CurContext && "skipping definition of undefined tag");
1092 // Start lookups from the parent of the current context; we don't want to look
1093 // into the pre-existing complete definition.
1094 S->setEntity(CurContext->getLookupParent());
1098 void Sema::ActOnTagFinishSkippedDefinition(SkippedDefinitionContext Context) {
1099 CurContext = static_cast<decltype(CurContext)>(Context);
1102 /// EnterDeclaratorContext - Used when we must lookup names in the context
1103 /// of a declarator's nested name specifier.
1105 void Sema::EnterDeclaratorContext(Scope *S, DeclContext *DC) {
1106 // C++0x [basic.lookup.unqual]p13:
1107 // A name used in the definition of a static data member of class
1108 // X (after the qualified-id of the static member) is looked up as
1109 // if the name was used in a member function of X.
1110 // C++0x [basic.lookup.unqual]p14:
1111 // If a variable member of a namespace is defined outside of the
1112 // scope of its namespace then any name used in the definition of
1113 // the variable member (after the declarator-id) is looked up as
1114 // if the definition of the variable member occurred in its
1116 // Both of these imply that we should push a scope whose context
1117 // is the semantic context of the declaration. We can't use
1118 // PushDeclContext here because that context is not necessarily
1119 // lexically contained in the current context. Fortunately,
1120 // the containing scope should have the appropriate information.
1122 assert(!S->getEntity() && "scope already has entity");
1125 Scope *Ancestor = S->getParent();
1126 while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent();
1127 assert(Ancestor->getEntity() == CurContext && "ancestor context mismatch");
1134 void Sema::ExitDeclaratorContext(Scope *S) {
1135 assert(S->getEntity() == CurContext && "Context imbalance!");
1137 // Switch back to the lexical context. The safety of this is
1138 // enforced by an assert in EnterDeclaratorContext.
1139 Scope *Ancestor = S->getParent();
1140 while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent();
1141 CurContext = Ancestor->getEntity();
1143 // We don't need to do anything with the scope, which is going to
1147 void Sema::ActOnReenterFunctionContext(Scope* S, Decl *D) {
1148 // We assume that the caller has already called
1149 // ActOnReenterTemplateScope so getTemplatedDecl() works.
1150 FunctionDecl *FD = D->getAsFunction();
1154 // Same implementation as PushDeclContext, but enters the context
1155 // from the lexical parent, rather than the top-level class.
1156 assert(CurContext == FD->getLexicalParent() &&
1157 "The next DeclContext should be lexically contained in the current one.");
1159 S->setEntity(CurContext);
1161 for (unsigned P = 0, NumParams = FD->getNumParams(); P < NumParams; ++P) {
1162 ParmVarDecl *Param = FD->getParamDecl(P);
1163 // If the parameter has an identifier, then add it to the scope
1164 if (Param->getIdentifier()) {
1166 IdResolver.AddDecl(Param);
1171 void Sema::ActOnExitFunctionContext() {
1172 // Same implementation as PopDeclContext, but returns to the lexical parent,
1173 // rather than the top-level class.
1174 assert(CurContext && "DeclContext imbalance!");
1175 CurContext = CurContext->getLexicalParent();
1176 assert(CurContext && "Popped translation unit!");
1179 /// \brief Determine whether we allow overloading of the function
1180 /// PrevDecl with another declaration.
1182 /// This routine determines whether overloading is possible, not
1183 /// whether some new function is actually an overload. It will return
1184 /// true in C++ (where we can always provide overloads) or, as an
1185 /// extension, in C when the previous function is already an
1186 /// overloaded function declaration or has the "overloadable"
1188 static bool AllowOverloadingOfFunction(LookupResult &Previous,
1189 ASTContext &Context) {
1190 if (Context.getLangOpts().CPlusPlus)
1193 if (Previous.getResultKind() == LookupResult::FoundOverloaded)
1196 return (Previous.getResultKind() == LookupResult::Found
1197 && Previous.getFoundDecl()->hasAttr<OverloadableAttr>());
1200 /// Add this decl to the scope shadowed decl chains.
1201 void Sema::PushOnScopeChains(NamedDecl *D, Scope *S, bool AddToContext) {
1202 // Move up the scope chain until we find the nearest enclosing
1203 // non-transparent context. The declaration will be introduced into this
1205 while (S->getEntity() && S->getEntity()->isTransparentContext())
1208 // Add scoped declarations into their context, so that they can be
1209 // found later. Declarations without a context won't be inserted
1210 // into any context.
1212 CurContext->addDecl(D);
1214 // Out-of-line definitions shouldn't be pushed into scope in C++, unless they
1215 // are function-local declarations.
1216 if (getLangOpts().CPlusPlus && D->isOutOfLine() &&
1217 !D->getDeclContext()->getRedeclContext()->Equals(
1218 D->getLexicalDeclContext()->getRedeclContext()) &&
1219 !D->getLexicalDeclContext()->isFunctionOrMethod())
1222 // Template instantiations should also not be pushed into scope.
1223 if (isa<FunctionDecl>(D) &&
1224 cast<FunctionDecl>(D)->isFunctionTemplateSpecialization())
1227 // If this replaces anything in the current scope,
1228 IdentifierResolver::iterator I = IdResolver.begin(D->getDeclName()),
1229 IEnd = IdResolver.end();
1230 for (; I != IEnd; ++I) {
1231 if (S->isDeclScope(*I) && D->declarationReplaces(*I)) {
1233 IdResolver.RemoveDecl(*I);
1235 // Should only need to replace one decl.
1242 if (isa<LabelDecl>(D) && !cast<LabelDecl>(D)->isGnuLocal()) {
1243 // Implicitly-generated labels may end up getting generated in an order that
1244 // isn't strictly lexical, which breaks name lookup. Be careful to insert
1245 // the label at the appropriate place in the identifier chain.
1246 for (I = IdResolver.begin(D->getDeclName()); I != IEnd; ++I) {
1247 DeclContext *IDC = (*I)->getLexicalDeclContext()->getRedeclContext();
1248 if (IDC == CurContext) {
1249 if (!S->isDeclScope(*I))
1251 } else if (IDC->Encloses(CurContext))
1255 IdResolver.InsertDeclAfter(I, D);
1257 IdResolver.AddDecl(D);
1261 void Sema::pushExternalDeclIntoScope(NamedDecl *D, DeclarationName Name) {
1262 if (IdResolver.tryAddTopLevelDecl(D, Name) && TUScope)
1263 TUScope->AddDecl(D);
1266 bool Sema::isDeclInScope(NamedDecl *D, DeclContext *Ctx, Scope *S,
1267 bool AllowInlineNamespace) {
1268 return IdResolver.isDeclInScope(D, Ctx, S, AllowInlineNamespace);
1271 Scope *Sema::getScopeForDeclContext(Scope *S, DeclContext *DC) {
1272 DeclContext *TargetDC = DC->getPrimaryContext();
1274 if (DeclContext *ScopeDC = S->getEntity())
1275 if (ScopeDC->getPrimaryContext() == TargetDC)
1277 } while ((S = S->getParent()));
1282 static bool isOutOfScopePreviousDeclaration(NamedDecl *,
1286 /// Filters out lookup results that don't fall within the given scope
1287 /// as determined by isDeclInScope.
1288 void Sema::FilterLookupForScope(LookupResult &R, DeclContext *Ctx, Scope *S,
1289 bool ConsiderLinkage,
1290 bool AllowInlineNamespace) {
1291 LookupResult::Filter F = R.makeFilter();
1292 while (F.hasNext()) {
1293 NamedDecl *D = F.next();
1295 if (isDeclInScope(D, Ctx, S, AllowInlineNamespace))
1298 if (ConsiderLinkage && isOutOfScopePreviousDeclaration(D, Ctx, Context))
1307 static bool isUsingDecl(NamedDecl *D) {
1308 return isa<UsingShadowDecl>(D) ||
1309 isa<UnresolvedUsingTypenameDecl>(D) ||
1310 isa<UnresolvedUsingValueDecl>(D);
1313 /// Removes using shadow declarations from the lookup results.
1314 static void RemoveUsingDecls(LookupResult &R) {
1315 LookupResult::Filter F = R.makeFilter();
1317 if (isUsingDecl(F.next()))
1323 /// \brief Check for this common pattern:
1326 /// S(const S&); // DO NOT IMPLEMENT
1327 /// void operator=(const S&); // DO NOT IMPLEMENT
1330 static bool IsDisallowedCopyOrAssign(const CXXMethodDecl *D) {
1331 // FIXME: Should check for private access too but access is set after we get
1333 if (D->doesThisDeclarationHaveABody())
1336 if (const CXXConstructorDecl *CD = dyn_cast<CXXConstructorDecl>(D))
1337 return CD->isCopyConstructor();
1338 if (const CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(D))
1339 return Method->isCopyAssignmentOperator();
1343 // We need this to handle
1346 // void *foo() { return 0; }
1349 // When we see foo we don't know if after the typedef we will get 'A' or '*A'
1350 // for example. If 'A', foo will have external linkage. If we have '*A',
1351 // foo will have no linkage. Since we can't know until we get to the end
1352 // of the typedef, this function finds out if D might have non-external linkage.
1353 // Callers should verify at the end of the TU if it D has external linkage or
1355 bool Sema::mightHaveNonExternalLinkage(const DeclaratorDecl *D) {
1356 const DeclContext *DC = D->getDeclContext();
1357 while (!DC->isTranslationUnit()) {
1358 if (const RecordDecl *RD = dyn_cast<RecordDecl>(DC)){
1359 if (!RD->hasNameForLinkage())
1362 DC = DC->getParent();
1365 return !D->isExternallyVisible();
1368 // FIXME: This needs to be refactored; some other isInMainFile users want
1370 static bool isMainFileLoc(const Sema &S, SourceLocation Loc) {
1371 if (S.TUKind != TU_Complete)
1373 return S.SourceMgr.isInMainFile(Loc);
1376 bool Sema::ShouldWarnIfUnusedFileScopedDecl(const DeclaratorDecl *D) const {
1379 if (D->isInvalidDecl() || D->isUsed() || D->hasAttr<UnusedAttr>())
1382 // Ignore all entities declared within templates, and out-of-line definitions
1383 // of members of class templates.
1384 if (D->getDeclContext()->isDependentContext() ||
1385 D->getLexicalDeclContext()->isDependentContext())
1388 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
1389 if (FD->getTemplateSpecializationKind() == TSK_ImplicitInstantiation)
1392 if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) {
1393 if (MD->isVirtual() || IsDisallowedCopyOrAssign(MD))
1396 // 'static inline' functions are defined in headers; don't warn.
1397 if (FD->isInlined() && !isMainFileLoc(*this, FD->getLocation()))
1401 if (FD->doesThisDeclarationHaveABody() &&
1402 Context.DeclMustBeEmitted(FD))
1404 } else if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
1405 // Constants and utility variables are defined in headers with internal
1406 // linkage; don't warn. (Unlike functions, there isn't a convenient marker
1408 if (!isMainFileLoc(*this, VD->getLocation()))
1411 if (Context.DeclMustBeEmitted(VD))
1414 if (VD->isStaticDataMember() &&
1415 VD->getTemplateSpecializationKind() == TSK_ImplicitInstantiation)
1421 // Only warn for unused decls internal to the translation unit.
1422 // FIXME: This seems like a bogus check; it suppresses -Wunused-function
1423 // for inline functions defined in the main source file, for instance.
1424 return mightHaveNonExternalLinkage(D);
1427 void Sema::MarkUnusedFileScopedDecl(const DeclaratorDecl *D) {
1431 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
1432 const FunctionDecl *First = FD->getFirstDecl();
1433 if (FD != First && ShouldWarnIfUnusedFileScopedDecl(First))
1434 return; // First should already be in the vector.
1437 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
1438 const VarDecl *First = VD->getFirstDecl();
1439 if (VD != First && ShouldWarnIfUnusedFileScopedDecl(First))
1440 return; // First should already be in the vector.
1443 if (ShouldWarnIfUnusedFileScopedDecl(D))
1444 UnusedFileScopedDecls.push_back(D);
1447 static bool ShouldDiagnoseUnusedDecl(const NamedDecl *D) {
1448 if (D->isInvalidDecl())
1451 if (D->isReferenced() || D->isUsed() || D->hasAttr<UnusedAttr>() ||
1452 D->hasAttr<ObjCPreciseLifetimeAttr>())
1455 if (isa<LabelDecl>(D))
1458 // Except for labels, we only care about unused decls that are local to
1460 bool WithinFunction = D->getDeclContext()->isFunctionOrMethod();
1461 if (const auto *R = dyn_cast<CXXRecordDecl>(D->getDeclContext()))
1462 // For dependent types, the diagnostic is deferred.
1464 WithinFunction || (R->isLocalClass() && !R->isDependentType());
1465 if (!WithinFunction)
1468 if (isa<TypedefNameDecl>(D))
1471 // White-list anything that isn't a local variable.
1472 if (!isa<VarDecl>(D) || isa<ParmVarDecl>(D) || isa<ImplicitParamDecl>(D))
1475 // Types of valid local variables should be complete, so this should succeed.
1476 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
1478 // White-list anything with an __attribute__((unused)) type.
1479 QualType Ty = VD->getType();
1481 // Only look at the outermost level of typedef.
1482 if (const TypedefType *TT = Ty->getAs<TypedefType>()) {
1483 if (TT->getDecl()->hasAttr<UnusedAttr>())
1487 // If we failed to complete the type for some reason, or if the type is
1488 // dependent, don't diagnose the variable.
1489 if (Ty->isIncompleteType() || Ty->isDependentType())
1492 if (const TagType *TT = Ty->getAs<TagType>()) {
1493 const TagDecl *Tag = TT->getDecl();
1494 if (Tag->hasAttr<UnusedAttr>())
1497 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(Tag)) {
1498 if (!RD->hasTrivialDestructor() && !RD->hasAttr<WarnUnusedAttr>())
1501 if (const Expr *Init = VD->getInit()) {
1502 if (const ExprWithCleanups *Cleanups =
1503 dyn_cast<ExprWithCleanups>(Init))
1504 Init = Cleanups->getSubExpr();
1505 const CXXConstructExpr *Construct =
1506 dyn_cast<CXXConstructExpr>(Init);
1507 if (Construct && !Construct->isElidable()) {
1508 CXXConstructorDecl *CD = Construct->getConstructor();
1509 if (!CD->isTrivial() && !RD->hasAttr<WarnUnusedAttr>())
1516 // TODO: __attribute__((unused)) templates?
1522 static void GenerateFixForUnusedDecl(const NamedDecl *D, ASTContext &Ctx,
1524 if (isa<LabelDecl>(D)) {
1525 SourceLocation AfterColon = Lexer::findLocationAfterToken(D->getLocEnd(),
1526 tok::colon, Ctx.getSourceManager(), Ctx.getLangOpts(), true);
1527 if (AfterColon.isInvalid())
1529 Hint = FixItHint::CreateRemoval(CharSourceRange::
1530 getCharRange(D->getLocStart(), AfterColon));
1534 void Sema::DiagnoseUnusedNestedTypedefs(const RecordDecl *D) {
1535 if (D->getTypeForDecl()->isDependentType())
1538 for (auto *TmpD : D->decls()) {
1539 if (const auto *T = dyn_cast<TypedefNameDecl>(TmpD))
1540 DiagnoseUnusedDecl(T);
1541 else if(const auto *R = dyn_cast<RecordDecl>(TmpD))
1542 DiagnoseUnusedNestedTypedefs(R);
1546 /// DiagnoseUnusedDecl - Emit warnings about declarations that are not used
1547 /// unless they are marked attr(unused).
1548 void Sema::DiagnoseUnusedDecl(const NamedDecl *D) {
1549 if (!ShouldDiagnoseUnusedDecl(D))
1552 if (auto *TD = dyn_cast<TypedefNameDecl>(D)) {
1553 // typedefs can be referenced later on, so the diagnostics are emitted
1554 // at end-of-translation-unit.
1555 UnusedLocalTypedefNameCandidates.insert(TD);
1560 GenerateFixForUnusedDecl(D, Context, Hint);
1563 if (isa<VarDecl>(D) && cast<VarDecl>(D)->isExceptionVariable())
1564 DiagID = diag::warn_unused_exception_param;
1565 else if (isa<LabelDecl>(D))
1566 DiagID = diag::warn_unused_label;
1568 DiagID = diag::warn_unused_variable;
1570 Diag(D->getLocation(), DiagID) << D->getDeclName() << Hint;
1573 static void CheckPoppedLabel(LabelDecl *L, Sema &S) {
1574 // Verify that we have no forward references left. If so, there was a goto
1575 // or address of a label taken, but no definition of it. Label fwd
1576 // definitions are indicated with a null substmt which is also not a resolved
1577 // MS inline assembly label name.
1578 bool Diagnose = false;
1579 if (L->isMSAsmLabel())
1580 Diagnose = !L->isResolvedMSAsmLabel();
1582 Diagnose = L->getStmt() == nullptr;
1584 S.Diag(L->getLocation(), diag::err_undeclared_label_use) <<L->getDeclName();
1587 void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) {
1588 S->mergeNRVOIntoParent();
1590 if (S->decl_empty()) return;
1591 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) &&
1592 "Scope shouldn't contain decls!");
1594 for (auto *TmpD : S->decls()) {
1595 assert(TmpD && "This decl didn't get pushed??");
1597 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?");
1598 NamedDecl *D = cast<NamedDecl>(TmpD);
1600 if (!D->getDeclName()) continue;
1602 // Diagnose unused variables in this scope.
1603 if (!S->hasUnrecoverableErrorOccurred()) {
1604 DiagnoseUnusedDecl(D);
1605 if (const auto *RD = dyn_cast<RecordDecl>(D))
1606 DiagnoseUnusedNestedTypedefs(RD);
1609 // If this was a forward reference to a label, verify it was defined.
1610 if (LabelDecl *LD = dyn_cast<LabelDecl>(D))
1611 CheckPoppedLabel(LD, *this);
1613 // Remove this name from our lexical scope.
1614 IdResolver.RemoveDecl(D);
1618 /// \brief Look for an Objective-C class in the translation unit.
1620 /// \param Id The name of the Objective-C class we're looking for. If
1621 /// typo-correction fixes this name, the Id will be updated
1622 /// to the fixed name.
1624 /// \param IdLoc The location of the name in the translation unit.
1626 /// \param DoTypoCorrection If true, this routine will attempt typo correction
1627 /// if there is no class with the given name.
1629 /// \returns The declaration of the named Objective-C class, or NULL if the
1630 /// class could not be found.
1631 ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *&Id,
1632 SourceLocation IdLoc,
1633 bool DoTypoCorrection) {
1634 // The third "scope" argument is 0 since we aren't enabling lazy built-in
1635 // creation from this context.
1636 NamedDecl *IDecl = LookupSingleName(TUScope, Id, IdLoc, LookupOrdinaryName);
1638 if (!IDecl && DoTypoCorrection) {
1639 // Perform typo correction at the given location, but only if we
1640 // find an Objective-C class name.
1641 if (TypoCorrection C = CorrectTypo(
1642 DeclarationNameInfo(Id, IdLoc), LookupOrdinaryName, TUScope, nullptr,
1643 llvm::make_unique<DeclFilterCCC<ObjCInterfaceDecl>>(),
1644 CTK_ErrorRecovery)) {
1645 diagnoseTypo(C, PDiag(diag::err_undef_interface_suggest) << Id);
1646 IDecl = C.getCorrectionDeclAs<ObjCInterfaceDecl>();
1647 Id = IDecl->getIdentifier();
1650 ObjCInterfaceDecl *Def = dyn_cast_or_null<ObjCInterfaceDecl>(IDecl);
1651 // This routine must always return a class definition, if any.
1652 if (Def && Def->getDefinition())
1653 Def = Def->getDefinition();
1657 /// getNonFieldDeclScope - Retrieves the innermost scope, starting
1658 /// from S, where a non-field would be declared. This routine copes
1659 /// with the difference between C and C++ scoping rules in structs and
1660 /// unions. For example, the following code is well-formed in C but
1661 /// ill-formed in C++:
1667 /// void test_S6() {
1672 /// For the declaration of BAR, this routine will return a different
1673 /// scope. The scope S will be the scope of the unnamed enumeration
1674 /// within S6. In C++, this routine will return the scope associated
1675 /// with S6, because the enumeration's scope is a transparent
1676 /// context but structures can contain non-field names. In C, this
1677 /// routine will return the translation unit scope, since the
1678 /// enumeration's scope is a transparent context and structures cannot
1679 /// contain non-field names.
1680 Scope *Sema::getNonFieldDeclScope(Scope *S) {
1681 while (((S->getFlags() & Scope::DeclScope) == 0) ||
1682 (S->getEntity() && S->getEntity()->isTransparentContext()) ||
1683 (S->isClassScope() && !getLangOpts().CPlusPlus))
1688 /// \brief Looks up the declaration of "struct objc_super" and
1689 /// saves it for later use in building builtin declaration of
1690 /// objc_msgSendSuper and objc_msgSendSuper_stret. If no such
1691 /// pre-existing declaration exists no action takes place.
1692 static void LookupPredefedObjCSuperType(Sema &ThisSema, Scope *S,
1693 IdentifierInfo *II) {
1694 if (!II->isStr("objc_msgSendSuper"))
1696 ASTContext &Context = ThisSema.Context;
1698 LookupResult Result(ThisSema, &Context.Idents.get("objc_super"),
1699 SourceLocation(), Sema::LookupTagName);
1700 ThisSema.LookupName(Result, S);
1701 if (Result.getResultKind() == LookupResult::Found)
1702 if (const TagDecl *TD = Result.getAsSingle<TagDecl>())
1703 Context.setObjCSuperType(Context.getTagDeclType(TD));
1706 static StringRef getHeaderName(ASTContext::GetBuiltinTypeError Error) {
1708 case ASTContext::GE_None:
1710 case ASTContext::GE_Missing_stdio:
1712 case ASTContext::GE_Missing_setjmp:
1714 case ASTContext::GE_Missing_ucontext:
1715 return "ucontext.h";
1717 llvm_unreachable("unhandled error kind");
1720 /// LazilyCreateBuiltin - The specified Builtin-ID was first used at
1721 /// file scope. lazily create a decl for it. ForRedeclaration is true
1722 /// if we're creating this built-in in anticipation of redeclaring the
1724 NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned ID,
1725 Scope *S, bool ForRedeclaration,
1726 SourceLocation Loc) {
1727 LookupPredefedObjCSuperType(*this, S, II);
1729 ASTContext::GetBuiltinTypeError Error;
1730 QualType R = Context.GetBuiltinType(ID, Error);
1732 if (ForRedeclaration)
1733 Diag(Loc, diag::warn_implicit_decl_requires_sysheader)
1734 << getHeaderName(Error) << Context.BuiltinInfo.getName(ID);
1738 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(ID)) {
1739 Diag(Loc, diag::ext_implicit_lib_function_decl)
1740 << Context.BuiltinInfo.getName(ID) << R;
1741 if (Context.BuiltinInfo.getHeaderName(ID) &&
1742 !Diags.isIgnored(diag::ext_implicit_lib_function_decl, Loc))
1743 Diag(Loc, diag::note_include_header_or_declare)
1744 << Context.BuiltinInfo.getHeaderName(ID)
1745 << Context.BuiltinInfo.getName(ID);
1751 DeclContext *Parent = Context.getTranslationUnitDecl();
1752 if (getLangOpts().CPlusPlus) {
1753 LinkageSpecDecl *CLinkageDecl =
1754 LinkageSpecDecl::Create(Context, Parent, Loc, Loc,
1755 LinkageSpecDecl::lang_c, false);
1756 CLinkageDecl->setImplicit();
1757 Parent->addDecl(CLinkageDecl);
1758 Parent = CLinkageDecl;
1761 FunctionDecl *New = FunctionDecl::Create(Context,
1763 Loc, Loc, II, R, /*TInfo=*/nullptr,
1766 R->isFunctionProtoType());
1769 // Create Decl objects for each parameter, adding them to the
1771 if (const FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) {
1772 SmallVector<ParmVarDecl*, 16> Params;
1773 for (unsigned i = 0, e = FT->getNumParams(); i != e; ++i) {
1775 ParmVarDecl::Create(Context, New, SourceLocation(), SourceLocation(),
1776 nullptr, FT->getParamType(i), /*TInfo=*/nullptr,
1778 parm->setScopeInfo(0, i);
1779 Params.push_back(parm);
1781 New->setParams(Params);
1784 AddKnownFunctionAttributes(New);
1785 RegisterLocallyScopedExternCDecl(New, S);
1787 // TUScope is the translation-unit scope to insert this function into.
1788 // FIXME: This is hideous. We need to teach PushOnScopeChains to
1789 // relate Scopes to DeclContexts, and probably eliminate CurContext
1790 // entirely, but we're not there yet.
1791 DeclContext *SavedContext = CurContext;
1792 CurContext = Parent;
1793 PushOnScopeChains(New, TUScope);
1794 CurContext = SavedContext;
1798 /// Typedef declarations don't have linkage, but they still denote the same
1799 /// entity if their types are the same.
1800 /// FIXME: This is notionally doing the same thing as ASTReaderDecl's
1802 static void filterNonConflictingPreviousTypedefDecls(Sema &S,
1803 TypedefNameDecl *Decl,
1804 LookupResult &Previous) {
1805 // This is only interesting when modules are enabled.
1806 if (!S.getLangOpts().Modules && !S.getLangOpts().ModulesLocalVisibility)
1809 // Empty sets are uninteresting.
1810 if (Previous.empty())
1813 LookupResult::Filter Filter = Previous.makeFilter();
1814 while (Filter.hasNext()) {
1815 NamedDecl *Old = Filter.next();
1817 // Non-hidden declarations are never ignored.
1818 if (S.isVisible(Old))
1821 // Declarations of the same entity are not ignored, even if they have
1822 // different linkages.
1823 if (auto *OldTD = dyn_cast<TypedefNameDecl>(Old)) {
1824 if (S.Context.hasSameType(OldTD->getUnderlyingType(),
1825 Decl->getUnderlyingType()))
1828 // If both declarations give a tag declaration a typedef name for linkage
1829 // purposes, then they declare the same entity.
1830 if (S.getLangOpts().CPlusPlus &&
1831 OldTD->getAnonDeclWithTypedefName(/*AnyRedecl*/true) &&
1832 Decl->getAnonDeclWithTypedefName())
1842 bool Sema::isIncompatibleTypedef(TypeDecl *Old, TypedefNameDecl *New) {
1844 if (TypedefNameDecl *OldTypedef = dyn_cast<TypedefNameDecl>(Old))
1845 OldType = OldTypedef->getUnderlyingType();
1847 OldType = Context.getTypeDeclType(Old);
1848 QualType NewType = New->getUnderlyingType();
1850 if (NewType->isVariablyModifiedType()) {
1851 // Must not redefine a typedef with a variably-modified type.
1852 int Kind = isa<TypeAliasDecl>(Old) ? 1 : 0;
1853 Diag(New->getLocation(), diag::err_redefinition_variably_modified_typedef)
1855 if (Old->getLocation().isValid())
1856 Diag(Old->getLocation(), diag::note_previous_definition);
1857 New->setInvalidDecl();
1861 if (OldType != NewType &&
1862 !OldType->isDependentType() &&
1863 !NewType->isDependentType() &&
1864 !Context.hasSameType(OldType, NewType)) {
1865 int Kind = isa<TypeAliasDecl>(Old) ? 1 : 0;
1866 Diag(New->getLocation(), diag::err_redefinition_different_typedef)
1867 << Kind << NewType << OldType;
1868 if (Old->getLocation().isValid())
1869 Diag(Old->getLocation(), diag::note_previous_definition);
1870 New->setInvalidDecl();
1876 /// MergeTypedefNameDecl - We just parsed a typedef 'New' which has the
1877 /// same name and scope as a previous declaration 'Old'. Figure out
1878 /// how to resolve this situation, merging decls or emitting
1879 /// diagnostics as appropriate. If there was an error, set New to be invalid.
1881 void Sema::MergeTypedefNameDecl(Scope *S, TypedefNameDecl *New,
1882 LookupResult &OldDecls) {
1883 // If the new decl is known invalid already, don't bother doing any
1885 if (New->isInvalidDecl()) return;
1887 // Allow multiple definitions for ObjC built-in typedefs.
1888 // FIXME: Verify the underlying types are equivalent!
1889 if (getLangOpts().ObjC1) {
1890 const IdentifierInfo *TypeID = New->getIdentifier();
1891 switch (TypeID->getLength()) {
1895 if (!TypeID->isStr("id"))
1897 QualType T = New->getUnderlyingType();
1898 if (!T->isPointerType())
1900 if (!T->isVoidPointerType()) {
1901 QualType PT = T->getAs<PointerType>()->getPointeeType();
1902 if (!PT->isStructureType())
1905 Context.setObjCIdRedefinitionType(T);
1906 // Install the built-in type for 'id', ignoring the current definition.
1907 New->setTypeForDecl(Context.getObjCIdType().getTypePtr());
1911 if (!TypeID->isStr("Class"))
1913 Context.setObjCClassRedefinitionType(New->getUnderlyingType());
1914 // Install the built-in type for 'Class', ignoring the current definition.
1915 New->setTypeForDecl(Context.getObjCClassType().getTypePtr());
1918 if (!TypeID->isStr("SEL"))
1920 Context.setObjCSelRedefinitionType(New->getUnderlyingType());
1921 // Install the built-in type for 'SEL', ignoring the current definition.
1922 New->setTypeForDecl(Context.getObjCSelType().getTypePtr());
1925 // Fall through - the typedef name was not a builtin type.
1928 // Verify the old decl was also a type.
1929 TypeDecl *Old = OldDecls.getAsSingle<TypeDecl>();
1931 Diag(New->getLocation(), diag::err_redefinition_different_kind)
1932 << New->getDeclName();
1934 NamedDecl *OldD = OldDecls.getRepresentativeDecl();
1935 if (OldD->getLocation().isValid())
1936 Diag(OldD->getLocation(), diag::note_previous_definition);
1938 return New->setInvalidDecl();
1941 // If the old declaration is invalid, just give up here.
1942 if (Old->isInvalidDecl())
1943 return New->setInvalidDecl();
1945 if (auto *OldTD = dyn_cast<TypedefNameDecl>(Old)) {
1946 auto *OldTag = OldTD->getAnonDeclWithTypedefName(/*AnyRedecl*/true);
1947 auto *NewTag = New->getAnonDeclWithTypedefName();
1948 NamedDecl *Hidden = nullptr;
1949 if (getLangOpts().CPlusPlus && OldTag && NewTag &&
1950 OldTag->getCanonicalDecl() != NewTag->getCanonicalDecl() &&
1951 !hasVisibleDefinition(OldTag, &Hidden)) {
1952 // There is a definition of this tag, but it is not visible. Use it
1953 // instead of our tag.
1954 New->setTypeForDecl(OldTD->getTypeForDecl());
1955 if (OldTD->isModed())
1956 New->setModedTypeSourceInfo(OldTD->getTypeSourceInfo(),
1957 OldTD->getUnderlyingType());
1959 New->setTypeSourceInfo(OldTD->getTypeSourceInfo());
1961 // Make the old tag definition visible.
1962 makeMergedDefinitionVisible(Hidden, NewTag->getLocation());
1964 // If this was an unscoped enumeration, yank all of its enumerators
1965 // out of the scope.
1966 if (isa<EnumDecl>(NewTag)) {
1967 Scope *EnumScope = getNonFieldDeclScope(S);
1968 for (auto *D : NewTag->decls()) {
1969 auto *ED = cast<EnumConstantDecl>(D);
1970 assert(EnumScope->isDeclScope(ED));
1971 EnumScope->RemoveDecl(ED);
1972 IdResolver.RemoveDecl(ED);
1973 ED->getLexicalDeclContext()->removeDecl(ED);
1979 // If the typedef types are not identical, reject them in all languages and
1980 // with any extensions enabled.
1981 if (isIncompatibleTypedef(Old, New))
1984 // The types match. Link up the redeclaration chain and merge attributes if
1985 // the old declaration was a typedef.
1986 if (TypedefNameDecl *Typedef = dyn_cast<TypedefNameDecl>(Old)) {
1987 New->setPreviousDecl(Typedef);
1988 mergeDeclAttributes(New, Old);
1991 if (getLangOpts().MicrosoftExt)
1994 if (getLangOpts().CPlusPlus) {
1995 // C++ [dcl.typedef]p2:
1996 // In a given non-class scope, a typedef specifier can be used to
1997 // redefine the name of any type declared in that scope to refer
1998 // to the type to which it already refers.
1999 if (!isa<CXXRecordDecl>(CurContext))
2002 // C++0x [dcl.typedef]p4:
2003 // In a given class scope, a typedef specifier can be used to redefine
2004 // any class-name declared in that scope that is not also a typedef-name
2005 // to refer to the type to which it already refers.
2007 // This wording came in via DR424, which was a correction to the
2008 // wording in DR56, which accidentally banned code like:
2011 // typedef struct A { } A;
2014 // in the C++03 standard. We implement the C++0x semantics, which
2015 // allow the above but disallow
2022 // since that was the intent of DR56.
2023 if (!isa<TypedefNameDecl>(Old))
2026 Diag(New->getLocation(), diag::err_redefinition)
2027 << New->getDeclName();
2028 Diag(Old->getLocation(), diag::note_previous_definition);
2029 return New->setInvalidDecl();
2032 // Modules always permit redefinition of typedefs, as does C11.
2033 if (getLangOpts().Modules || getLangOpts().C11)
2036 // If we have a redefinition of a typedef in C, emit a warning. This warning
2037 // is normally mapped to an error, but can be controlled with
2038 // -Wtypedef-redefinition. If either the original or the redefinition is
2039 // in a system header, don't emit this for compatibility with GCC.
2040 if (getDiagnostics().getSuppressSystemWarnings() &&
2041 (Context.getSourceManager().isInSystemHeader(Old->getLocation()) ||
2042 Context.getSourceManager().isInSystemHeader(New->getLocation())))
2045 Diag(New->getLocation(), diag::ext_redefinition_of_typedef)
2046 << New->getDeclName();
2047 Diag(Old->getLocation(), diag::note_previous_definition);
2050 /// DeclhasAttr - returns true if decl Declaration already has the target
2052 static bool DeclHasAttr(const Decl *D, const Attr *A) {
2053 const OwnershipAttr *OA = dyn_cast<OwnershipAttr>(A);
2054 const AnnotateAttr *Ann = dyn_cast<AnnotateAttr>(A);
2055 for (const auto *i : D->attrs())
2056 if (i->getKind() == A->getKind()) {
2058 if (Ann->getAnnotation() == cast<AnnotateAttr>(i)->getAnnotation())
2062 // FIXME: Don't hardcode this check
2063 if (OA && isa<OwnershipAttr>(i))
2064 return OA->getOwnKind() == cast<OwnershipAttr>(i)->getOwnKind();
2071 static bool isAttributeTargetADefinition(Decl *D) {
2072 if (VarDecl *VD = dyn_cast<VarDecl>(D))
2073 return VD->isThisDeclarationADefinition();
2074 if (TagDecl *TD = dyn_cast<TagDecl>(D))
2075 return TD->isCompleteDefinition() || TD->isBeingDefined();
2079 /// Merge alignment attributes from \p Old to \p New, taking into account the
2080 /// special semantics of C11's _Alignas specifier and C++11's alignas attribute.
2082 /// \return \c true if any attributes were added to \p New.
2083 static bool mergeAlignedAttrs(Sema &S, NamedDecl *New, Decl *Old) {
2084 // Look for alignas attributes on Old, and pick out whichever attribute
2085 // specifies the strictest alignment requirement.
2086 AlignedAttr *OldAlignasAttr = nullptr;
2087 AlignedAttr *OldStrictestAlignAttr = nullptr;
2088 unsigned OldAlign = 0;
2089 for (auto *I : Old->specific_attrs<AlignedAttr>()) {
2090 // FIXME: We have no way of representing inherited dependent alignments
2092 // template<int A, int B> struct alignas(A) X;
2093 // template<int A, int B> struct alignas(B) X {};
2094 // For now, we just ignore any alignas attributes which are not on the
2095 // definition in such a case.
2096 if (I->isAlignmentDependent())
2102 unsigned Align = I->getAlignment(S.Context);
2103 if (Align > OldAlign) {
2105 OldStrictestAlignAttr = I;
2109 // Look for alignas attributes on New.
2110 AlignedAttr *NewAlignasAttr = nullptr;
2111 unsigned NewAlign = 0;
2112 for (auto *I : New->specific_attrs<AlignedAttr>()) {
2113 if (I->isAlignmentDependent())
2119 unsigned Align = I->getAlignment(S.Context);
2120 if (Align > NewAlign)
2124 if (OldAlignasAttr && NewAlignasAttr && OldAlign != NewAlign) {
2125 // Both declarations have 'alignas' attributes. We require them to match.
2126 // C++11 [dcl.align]p6 and C11 6.7.5/7 both come close to saying this, but
2127 // fall short. (If two declarations both have alignas, they must both match
2128 // every definition, and so must match each other if there is a definition.)
2130 // If either declaration only contains 'alignas(0)' specifiers, then it
2131 // specifies the natural alignment for the type.
2132 if (OldAlign == 0 || NewAlign == 0) {
2134 if (ValueDecl *VD = dyn_cast<ValueDecl>(New))
2137 Ty = S.Context.getTagDeclType(cast<TagDecl>(New));
2140 OldAlign = S.Context.getTypeAlign(Ty);
2142 NewAlign = S.Context.getTypeAlign(Ty);
2145 if (OldAlign != NewAlign) {
2146 S.Diag(NewAlignasAttr->getLocation(), diag::err_alignas_mismatch)
2147 << (unsigned)S.Context.toCharUnitsFromBits(OldAlign).getQuantity()
2148 << (unsigned)S.Context.toCharUnitsFromBits(NewAlign).getQuantity();
2149 S.Diag(OldAlignasAttr->getLocation(), diag::note_previous_declaration);
2153 if (OldAlignasAttr && !NewAlignasAttr && isAttributeTargetADefinition(New)) {
2154 // C++11 [dcl.align]p6:
2155 // if any declaration of an entity has an alignment-specifier,
2156 // every defining declaration of that entity shall specify an
2157 // equivalent alignment.
2159 // If the definition of an object does not have an alignment
2160 // specifier, any other declaration of that object shall also
2161 // have no alignment specifier.
2162 S.Diag(New->getLocation(), diag::err_alignas_missing_on_definition)
2164 S.Diag(OldAlignasAttr->getLocation(), diag::note_alignas_on_declaration)
2168 bool AnyAdded = false;
2170 // Ensure we have an attribute representing the strictest alignment.
2171 if (OldAlign > NewAlign) {
2172 AlignedAttr *Clone = OldStrictestAlignAttr->clone(S.Context);
2173 Clone->setInherited(true);
2174 New->addAttr(Clone);
2178 // Ensure we have an alignas attribute if the old declaration had one.
2179 if (OldAlignasAttr && !NewAlignasAttr &&
2180 !(AnyAdded && OldStrictestAlignAttr->isAlignas())) {
2181 AlignedAttr *Clone = OldAlignasAttr->clone(S.Context);
2182 Clone->setInherited(true);
2183 New->addAttr(Clone);
2190 static bool mergeDeclAttribute(Sema &S, NamedDecl *D,
2191 const InheritableAttr *Attr,
2192 Sema::AvailabilityMergeKind AMK) {
2193 InheritableAttr *NewAttr = nullptr;
2194 unsigned AttrSpellingListIndex = Attr->getSpellingListIndex();
2195 if (const auto *AA = dyn_cast<AvailabilityAttr>(Attr))
2196 NewAttr = S.mergeAvailabilityAttr(D, AA->getRange(), AA->getPlatform(),
2197 AA->getIntroduced(), AA->getDeprecated(),
2198 AA->getObsoleted(), AA->getUnavailable(),
2199 AA->getMessage(), AA->getNopartial(), AMK,
2200 AttrSpellingListIndex);
2201 else if (const auto *VA = dyn_cast<VisibilityAttr>(Attr))
2202 NewAttr = S.mergeVisibilityAttr(D, VA->getRange(), VA->getVisibility(),
2203 AttrSpellingListIndex);
2204 else if (const auto *VA = dyn_cast<TypeVisibilityAttr>(Attr))
2205 NewAttr = S.mergeTypeVisibilityAttr(D, VA->getRange(), VA->getVisibility(),
2206 AttrSpellingListIndex);
2207 else if (const auto *ImportA = dyn_cast<DLLImportAttr>(Attr))
2208 NewAttr = S.mergeDLLImportAttr(D, ImportA->getRange(),
2209 AttrSpellingListIndex);
2210 else if (const auto *ExportA = dyn_cast<DLLExportAttr>(Attr))
2211 NewAttr = S.mergeDLLExportAttr(D, ExportA->getRange(),
2212 AttrSpellingListIndex);
2213 else if (const auto *FA = dyn_cast<FormatAttr>(Attr))
2214 NewAttr = S.mergeFormatAttr(D, FA->getRange(), FA->getType(),
2215 FA->getFormatIdx(), FA->getFirstArg(),
2216 AttrSpellingListIndex);
2217 else if (const auto *SA = dyn_cast<SectionAttr>(Attr))
2218 NewAttr = S.mergeSectionAttr(D, SA->getRange(), SA->getName(),
2219 AttrSpellingListIndex);
2220 else if (const auto *IA = dyn_cast<MSInheritanceAttr>(Attr))
2221 NewAttr = S.mergeMSInheritanceAttr(D, IA->getRange(), IA->getBestCase(),
2222 AttrSpellingListIndex,
2223 IA->getSemanticSpelling());
2224 else if (const auto *AA = dyn_cast<AlwaysInlineAttr>(Attr))
2225 NewAttr = S.mergeAlwaysInlineAttr(D, AA->getRange(),
2226 &S.Context.Idents.get(AA->getSpelling()),
2227 AttrSpellingListIndex);
2228 else if (const auto *MA = dyn_cast<MinSizeAttr>(Attr))
2229 NewAttr = S.mergeMinSizeAttr(D, MA->getRange(), AttrSpellingListIndex);
2230 else if (const auto *OA = dyn_cast<OptimizeNoneAttr>(Attr))
2231 NewAttr = S.mergeOptimizeNoneAttr(D, OA->getRange(), AttrSpellingListIndex);
2232 else if (const auto *InternalLinkageA = dyn_cast<InternalLinkageAttr>(Attr))
2233 NewAttr = S.mergeInternalLinkageAttr(
2234 D, InternalLinkageA->getRange(),
2235 &S.Context.Idents.get(InternalLinkageA->getSpelling()),
2236 AttrSpellingListIndex);
2237 else if (const auto *CommonA = dyn_cast<CommonAttr>(Attr))
2238 NewAttr = S.mergeCommonAttr(D, CommonA->getRange(),
2239 &S.Context.Idents.get(CommonA->getSpelling()),
2240 AttrSpellingListIndex);
2241 else if (isa<AlignedAttr>(Attr))
2242 // AlignedAttrs are handled separately, because we need to handle all
2243 // such attributes on a declaration at the same time.
2245 else if ((isa<DeprecatedAttr>(Attr) || isa<UnavailableAttr>(Attr)) &&
2246 (AMK == Sema::AMK_Override ||
2247 AMK == Sema::AMK_ProtocolImplementation))
2249 else if (Attr->duplicatesAllowed() || !DeclHasAttr(D, Attr))
2250 NewAttr = cast<InheritableAttr>(Attr->clone(S.Context));
2253 NewAttr->setInherited(true);
2254 D->addAttr(NewAttr);
2255 if (isa<MSInheritanceAttr>(NewAttr))
2256 S.Consumer.AssignInheritanceModel(cast<CXXRecordDecl>(D));
2263 static const Decl *getDefinition(const Decl *D) {
2264 if (const TagDecl *TD = dyn_cast<TagDecl>(D))
2265 return TD->getDefinition();
2266 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
2267 const VarDecl *Def = VD->getDefinition();
2270 return VD->getActingDefinition();
2272 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
2273 const FunctionDecl* Def;
2274 if (FD->isDefined(Def))
2280 static bool hasAttribute(const Decl *D, attr::Kind Kind) {
2281 for (const auto *Attribute : D->attrs())
2282 if (Attribute->getKind() == Kind)
2287 /// checkNewAttributesAfterDef - If we already have a definition, check that
2288 /// there are no new attributes in this declaration.
2289 static void checkNewAttributesAfterDef(Sema &S, Decl *New, const Decl *Old) {
2290 if (!New->hasAttrs())
2293 const Decl *Def = getDefinition(Old);
2294 if (!Def || Def == New)
2297 AttrVec &NewAttributes = New->getAttrs();
2298 for (unsigned I = 0, E = NewAttributes.size(); I != E;) {
2299 const Attr *NewAttribute = NewAttributes[I];
2301 if (isa<AliasAttr>(NewAttribute)) {
2302 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(New)) {
2303 Sema::SkipBodyInfo SkipBody;
2304 S.CheckForFunctionRedefinition(FD, cast<FunctionDecl>(Def), &SkipBody);
2306 // If we're skipping this definition, drop the "alias" attribute.
2307 if (SkipBody.ShouldSkip) {
2308 NewAttributes.erase(NewAttributes.begin() + I);
2313 VarDecl *VD = cast<VarDecl>(New);
2314 unsigned Diag = cast<VarDecl>(Def)->isThisDeclarationADefinition() ==
2315 VarDecl::TentativeDefinition
2316 ? diag::err_alias_after_tentative
2317 : diag::err_redefinition;
2318 S.Diag(VD->getLocation(), Diag) << VD->getDeclName();
2319 S.Diag(Def->getLocation(), diag::note_previous_definition);
2320 VD->setInvalidDecl();
2326 if (const VarDecl *VD = dyn_cast<VarDecl>(Def)) {
2327 // Tentative definitions are only interesting for the alias check above.
2328 if (VD->isThisDeclarationADefinition() != VarDecl::Definition) {
2334 if (hasAttribute(Def, NewAttribute->getKind())) {
2336 continue; // regular attr merging will take care of validating this.
2339 if (isa<C11NoReturnAttr>(NewAttribute)) {
2340 // C's _Noreturn is allowed to be added to a function after it is defined.
2343 } else if (const AlignedAttr *AA = dyn_cast<AlignedAttr>(NewAttribute)) {
2344 if (AA->isAlignas()) {
2345 // C++11 [dcl.align]p6:
2346 // if any declaration of an entity has an alignment-specifier,
2347 // every defining declaration of that entity shall specify an
2348 // equivalent alignment.
2350 // If the definition of an object does not have an alignment
2351 // specifier, any other declaration of that object shall also
2352 // have no alignment specifier.
2353 S.Diag(Def->getLocation(), diag::err_alignas_missing_on_definition)
2355 S.Diag(NewAttribute->getLocation(), diag::note_alignas_on_declaration)
2357 NewAttributes.erase(NewAttributes.begin() + I);
2363 S.Diag(NewAttribute->getLocation(),
2364 diag::warn_attribute_precede_definition);
2365 S.Diag(Def->getLocation(), diag::note_previous_definition);
2366 NewAttributes.erase(NewAttributes.begin() + I);
2371 /// mergeDeclAttributes - Copy attributes from the Old decl to the New one.
2372 void Sema::mergeDeclAttributes(NamedDecl *New, Decl *Old,
2373 AvailabilityMergeKind AMK) {
2374 if (UsedAttr *OldAttr = Old->getMostRecentDecl()->getAttr<UsedAttr>()) {
2375 UsedAttr *NewAttr = OldAttr->clone(Context);
2376 NewAttr->setInherited(true);
2377 New->addAttr(NewAttr);
2380 if (!Old->hasAttrs() && !New->hasAttrs())
2383 // Attributes declared post-definition are currently ignored.
2384 checkNewAttributesAfterDef(*this, New, Old);
2386 if (AsmLabelAttr *NewA = New->getAttr<AsmLabelAttr>()) {
2387 if (AsmLabelAttr *OldA = Old->getAttr<AsmLabelAttr>()) {
2388 if (OldA->getLabel() != NewA->getLabel()) {
2389 // This redeclaration changes __asm__ label.
2390 Diag(New->getLocation(), diag::err_different_asm_label);
2391 Diag(OldA->getLocation(), diag::note_previous_declaration);
2393 } else if (Old->isUsed()) {
2394 // This redeclaration adds an __asm__ label to a declaration that has
2395 // already been ODR-used.
2396 Diag(New->getLocation(), diag::err_late_asm_label_name)
2397 << isa<FunctionDecl>(Old) << New->getAttr<AsmLabelAttr>()->getRange();
2401 if (!Old->hasAttrs())
2404 bool foundAny = New->hasAttrs();
2406 // Ensure that any moving of objects within the allocated map is done before
2408 if (!foundAny) New->setAttrs(AttrVec());
2410 for (auto *I : Old->specific_attrs<InheritableAttr>()) {
2411 // Ignore deprecated/unavailable/availability attributes if requested.
2412 AvailabilityMergeKind LocalAMK = AMK_None;
2413 if (isa<DeprecatedAttr>(I) ||
2414 isa<UnavailableAttr>(I) ||
2415 isa<AvailabilityAttr>(I)) {
2420 case AMK_Redeclaration:
2422 case AMK_ProtocolImplementation:
2429 if (isa<UsedAttr>(I))
2432 if (mergeDeclAttribute(*this, New, I, LocalAMK))
2436 if (mergeAlignedAttrs(*this, New, Old))
2439 if (!foundAny) New->dropAttrs();
2442 /// mergeParamDeclAttributes - Copy attributes from the old parameter
2444 static void mergeParamDeclAttributes(ParmVarDecl *newDecl,
2445 const ParmVarDecl *oldDecl,
2447 // C++11 [dcl.attr.depend]p2:
2448 // The first declaration of a function shall specify the
2449 // carries_dependency attribute for its declarator-id if any declaration
2450 // of the function specifies the carries_dependency attribute.
2451 const CarriesDependencyAttr *CDA = newDecl->getAttr<CarriesDependencyAttr>();
2452 if (CDA && !oldDecl->hasAttr<CarriesDependencyAttr>()) {
2453 S.Diag(CDA->getLocation(),
2454 diag::err_carries_dependency_missing_on_first_decl) << 1/*Param*/;
2455 // Find the first declaration of the parameter.
2456 // FIXME: Should we build redeclaration chains for function parameters?
2457 const FunctionDecl *FirstFD =
2458 cast<FunctionDecl>(oldDecl->getDeclContext())->getFirstDecl();
2459 const ParmVarDecl *FirstVD =
2460 FirstFD->getParamDecl(oldDecl->getFunctionScopeIndex());
2461 S.Diag(FirstVD->getLocation(),
2462 diag::note_carries_dependency_missing_first_decl) << 1/*Param*/;
2465 if (!oldDecl->hasAttrs())
2468 bool foundAny = newDecl->hasAttrs();
2470 // Ensure that any moving of objects within the allocated map is
2471 // done before we process them.
2472 if (!foundAny) newDecl->setAttrs(AttrVec());
2474 for (const auto *I : oldDecl->specific_attrs<InheritableParamAttr>()) {
2475 if (!DeclHasAttr(newDecl, I)) {
2476 InheritableAttr *newAttr =
2477 cast<InheritableParamAttr>(I->clone(S.Context));
2478 newAttr->setInherited(true);
2479 newDecl->addAttr(newAttr);
2484 if (!foundAny) newDecl->dropAttrs();
2487 static void mergeParamDeclTypes(ParmVarDecl *NewParam,
2488 const ParmVarDecl *OldParam,
2490 if (auto Oldnullability = OldParam->getType()->getNullability(S.Context)) {
2491 if (auto Newnullability = NewParam->getType()->getNullability(S.Context)) {
2492 if (*Oldnullability != *Newnullability) {
2493 S.Diag(NewParam->getLocation(), diag::warn_mismatched_nullability_attr)
2494 << DiagNullabilityKind(
2496 ((NewParam->getObjCDeclQualifier() & Decl::OBJC_TQ_CSNullability)
2498 << DiagNullabilityKind(
2500 ((OldParam->getObjCDeclQualifier() & Decl::OBJC_TQ_CSNullability)
2502 S.Diag(OldParam->getLocation(), diag::note_previous_declaration);
2505 QualType NewT = NewParam->getType();
2506 NewT = S.Context.getAttributedType(
2507 AttributedType::getNullabilityAttrKind(*Oldnullability),
2509 NewParam->setType(NewT);
2516 /// Used in MergeFunctionDecl to keep track of function parameters in
2518 struct GNUCompatibleParamWarning {
2519 ParmVarDecl *OldParm;
2520 ParmVarDecl *NewParm;
2521 QualType PromotedType;
2524 } // end anonymous namespace
2526 /// getSpecialMember - get the special member enum for a method.
2527 Sema::CXXSpecialMember Sema::getSpecialMember(const CXXMethodDecl *MD) {
2528 if (const CXXConstructorDecl *Ctor = dyn_cast<CXXConstructorDecl>(MD)) {
2529 if (Ctor->isDefaultConstructor())
2530 return Sema::CXXDefaultConstructor;
2532 if (Ctor->isCopyConstructor())
2533 return Sema::CXXCopyConstructor;
2535 if (Ctor->isMoveConstructor())
2536 return Sema::CXXMoveConstructor;
2537 } else if (isa<CXXDestructorDecl>(MD)) {
2538 return Sema::CXXDestructor;
2539 } else if (MD->isCopyAssignmentOperator()) {
2540 return Sema::CXXCopyAssignment;
2541 } else if (MD->isMoveAssignmentOperator()) {
2542 return Sema::CXXMoveAssignment;
2545 return Sema::CXXInvalid;
2548 // Determine whether the previous declaration was a definition, implicit
2549 // declaration, or a declaration.
2550 template <typename T>
2551 static std::pair<diag::kind, SourceLocation>
2552 getNoteDiagForInvalidRedeclaration(const T *Old, const T *New) {
2553 diag::kind PrevDiag;
2554 SourceLocation OldLocation = Old->getLocation();
2555 if (Old->isThisDeclarationADefinition())
2556 PrevDiag = diag::note_previous_definition;
2557 else if (Old->isImplicit()) {
2558 PrevDiag = diag::note_previous_implicit_declaration;
2559 if (OldLocation.isInvalid())
2560 OldLocation = New->getLocation();
2562 PrevDiag = diag::note_previous_declaration;
2563 return std::make_pair(PrevDiag, OldLocation);
2566 /// canRedefineFunction - checks if a function can be redefined. Currently,
2567 /// only extern inline functions can be redefined, and even then only in
2569 static bool canRedefineFunction(const FunctionDecl *FD,
2570 const LangOptions& LangOpts) {
2571 return ((FD->hasAttr<GNUInlineAttr>() || LangOpts.GNUInline) &&
2572 !LangOpts.CPlusPlus &&
2573 FD->isInlineSpecified() &&
2574 FD->getStorageClass() == SC_Extern);
2577 const AttributedType *Sema::getCallingConvAttributedType(QualType T) const {
2578 const AttributedType *AT = T->getAs<AttributedType>();
2579 while (AT && !AT->isCallingConv())
2580 AT = AT->getModifiedType()->getAs<AttributedType>();
2584 template <typename T>
2585 static bool haveIncompatibleLanguageLinkages(const T *Old, const T *New) {
2586 const DeclContext *DC = Old->getDeclContext();
2590 LanguageLinkage OldLinkage = Old->getLanguageLinkage();
2591 if (OldLinkage == CXXLanguageLinkage && New->isInExternCContext())
2593 if (OldLinkage == CLanguageLinkage && New->isInExternCXXContext())
2598 template<typename T> static bool isExternC(T *D) { return D->isExternC(); }
2599 static bool isExternC(VarTemplateDecl *) { return false; }
2601 /// \brief Check whether a redeclaration of an entity introduced by a
2602 /// using-declaration is valid, given that we know it's not an overload
2603 /// (nor a hidden tag declaration).
2604 template<typename ExpectedDecl>
2605 static bool checkUsingShadowRedecl(Sema &S, UsingShadowDecl *OldS,
2606 ExpectedDecl *New) {
2607 // C++11 [basic.scope.declarative]p4:
2608 // Given a set of declarations in a single declarative region, each of
2609 // which specifies the same unqualified name,
2610 // -- they shall all refer to the same entity, or all refer to functions
2611 // and function templates; or
2612 // -- exactly one declaration shall declare a class name or enumeration
2613 // name that is not a typedef name and the other declarations shall all
2614 // refer to the same variable or enumerator, or all refer to functions
2615 // and function templates; in this case the class name or enumeration
2616 // name is hidden (3.3.10).
2618 // C++11 [namespace.udecl]p14:
2619 // If a function declaration in namespace scope or block scope has the
2620 // same name and the same parameter-type-list as a function introduced
2621 // by a using-declaration, and the declarations do not declare the same
2622 // function, the program is ill-formed.
2624 auto *Old = dyn_cast<ExpectedDecl>(OldS->getTargetDecl());
2626 !Old->getDeclContext()->getRedeclContext()->Equals(
2627 New->getDeclContext()->getRedeclContext()) &&
2628 !(isExternC(Old) && isExternC(New)))
2632 S.Diag(New->getLocation(), diag::err_using_decl_conflict_reverse);
2633 S.Diag(OldS->getTargetDecl()->getLocation(), diag::note_using_decl_target);
2634 S.Diag(OldS->getUsingDecl()->getLocation(), diag::note_using_decl) << 0;
2640 static bool hasIdenticalPassObjectSizeAttrs(const FunctionDecl *A,
2641 const FunctionDecl *B) {
2642 assert(A->getNumParams() == B->getNumParams());
2644 auto AttrEq = [](const ParmVarDecl *A, const ParmVarDecl *B) {
2645 const auto *AttrA = A->getAttr<PassObjectSizeAttr>();
2646 const auto *AttrB = B->getAttr<PassObjectSizeAttr>();
2649 return AttrA && AttrB && AttrA->getType() == AttrB->getType();
2652 return std::equal(A->param_begin(), A->param_end(), B->param_begin(), AttrEq);
2655 /// MergeFunctionDecl - We just parsed a function 'New' from
2656 /// declarator D which has the same name and scope as a previous
2657 /// declaration 'Old'. Figure out how to resolve this situation,
2658 /// merging decls or emitting diagnostics as appropriate.
2660 /// In C++, New and Old must be declarations that are not
2661 /// overloaded. Use IsOverload to determine whether New and Old are
2662 /// overloaded, and to select the Old declaration that New should be
2665 /// Returns true if there was an error, false otherwise.
2666 bool Sema::MergeFunctionDecl(FunctionDecl *New, NamedDecl *&OldD,
2667 Scope *S, bool MergeTypeWithOld) {
2668 // Verify the old decl was also a function.
2669 FunctionDecl *Old = OldD->getAsFunction();
2671 if (UsingShadowDecl *Shadow = dyn_cast<UsingShadowDecl>(OldD)) {
2672 if (New->getFriendObjectKind()) {
2673 Diag(New->getLocation(), diag::err_using_decl_friend);
2674 Diag(Shadow->getTargetDecl()->getLocation(),
2675 diag::note_using_decl_target);
2676 Diag(Shadow->getUsingDecl()->getLocation(),
2677 diag::note_using_decl) << 0;
2681 // Check whether the two declarations might declare the same function.
2682 if (checkUsingShadowRedecl<FunctionDecl>(*this, Shadow, New))
2684 OldD = Old = cast<FunctionDecl>(Shadow->getTargetDecl());
2686 Diag(New->getLocation(), diag::err_redefinition_different_kind)
2687 << New->getDeclName();
2688 Diag(OldD->getLocation(), diag::note_previous_definition);
2693 // If the old declaration is invalid, just give up here.
2694 if (Old->isInvalidDecl())
2697 diag::kind PrevDiag;
2698 SourceLocation OldLocation;
2699 std::tie(PrevDiag, OldLocation) =
2700 getNoteDiagForInvalidRedeclaration(Old, New);
2702 // Don't complain about this if we're in GNU89 mode and the old function
2703 // is an extern inline function.
2704 // Don't complain about specializations. They are not supposed to have
2706 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) &&
2707 New->getStorageClass() == SC_Static &&
2708 Old->hasExternalFormalLinkage() &&
2709 !New->getTemplateSpecializationInfo() &&
2710 !canRedefineFunction(Old, getLangOpts())) {
2711 if (getLangOpts().MicrosoftExt) {
2712 Diag(New->getLocation(), diag::ext_static_non_static) << New;
2713 Diag(OldLocation, PrevDiag);
2715 Diag(New->getLocation(), diag::err_static_non_static) << New;
2716 Diag(OldLocation, PrevDiag);
2721 if (New->hasAttr<InternalLinkageAttr>() &&
2722 !Old->hasAttr<InternalLinkageAttr>()) {
2723 Diag(New->getLocation(), diag::err_internal_linkage_redeclaration)
2724 << New->getDeclName();
2725 Diag(Old->getLocation(), diag::note_previous_definition);
2726 New->dropAttr<InternalLinkageAttr>();
2729 // If a function is first declared with a calling convention, but is later
2730 // declared or defined without one, all following decls assume the calling
2731 // convention of the first.
2733 // It's OK if a function is first declared without a calling convention,
2734 // but is later declared or defined with the default calling convention.
2736 // To test if either decl has an explicit calling convention, we look for
2737 // AttributedType sugar nodes on the type as written. If they are missing or
2738 // were canonicalized away, we assume the calling convention was implicit.
2740 // Note also that we DO NOT return at this point, because we still have
2741 // other tests to run.
2742 QualType OldQType = Context.getCanonicalType(Old->getType());
2743 QualType NewQType = Context.getCanonicalType(New->getType());
2744 const FunctionType *OldType = cast<FunctionType>(OldQType);
2745 const FunctionType *NewType = cast<FunctionType>(NewQType);
2746 FunctionType::ExtInfo OldTypeInfo = OldType->getExtInfo();
2747 FunctionType::ExtInfo NewTypeInfo = NewType->getExtInfo();
2748 bool RequiresAdjustment = false;
2750 if (OldTypeInfo.getCC() != NewTypeInfo.getCC()) {
2751 FunctionDecl *First = Old->getFirstDecl();
2752 const FunctionType *FT =
2753 First->getType().getCanonicalType()->castAs<FunctionType>();
2754 FunctionType::ExtInfo FI = FT->getExtInfo();
2755 bool NewCCExplicit = getCallingConvAttributedType(New->getType());
2756 if (!NewCCExplicit) {
2757 // Inherit the CC from the previous declaration if it was specified
2758 // there but not here.
2759 NewTypeInfo = NewTypeInfo.withCallingConv(OldTypeInfo.getCC());
2760 RequiresAdjustment = true;
2762 // Calling conventions aren't compatible, so complain.
2763 bool FirstCCExplicit = getCallingConvAttributedType(First->getType());
2764 Diag(New->getLocation(), diag::err_cconv_change)
2765 << FunctionType::getNameForCallConv(NewTypeInfo.getCC())
2767 << (!FirstCCExplicit ? "" :
2768 FunctionType::getNameForCallConv(FI.getCC()));
2770 // Put the note on the first decl, since it is the one that matters.
2771 Diag(First->getLocation(), diag::note_previous_declaration);
2776 // FIXME: diagnose the other way around?
2777 if (OldTypeInfo.getNoReturn() && !NewTypeInfo.getNoReturn()) {
2778 NewTypeInfo = NewTypeInfo.withNoReturn(true);
2779 RequiresAdjustment = true;
2782 // Merge regparm attribute.
2783 if (OldTypeInfo.getHasRegParm() != NewTypeInfo.getHasRegParm() ||
2784 OldTypeInfo.getRegParm() != NewTypeInfo.getRegParm()) {
2785 if (NewTypeInfo.getHasRegParm()) {
2786 Diag(New->getLocation(), diag::err_regparm_mismatch)
2787 << NewType->getRegParmType()
2788 << OldType->getRegParmType();
2789 Diag(OldLocation, diag::note_previous_declaration);
2793 NewTypeInfo = NewTypeInfo.withRegParm(OldTypeInfo.getRegParm());
2794 RequiresAdjustment = true;
2797 // Merge ns_returns_retained attribute.
2798 if (OldTypeInfo.getProducesResult() != NewTypeInfo.getProducesResult()) {
2799 if (NewTypeInfo.getProducesResult()) {
2800 Diag(New->getLocation(), diag::err_returns_retained_mismatch);
2801 Diag(OldLocation, diag::note_previous_declaration);
2805 NewTypeInfo = NewTypeInfo.withProducesResult(true);
2806 RequiresAdjustment = true;
2809 if (RequiresAdjustment) {
2810 const FunctionType *AdjustedType = New->getType()->getAs<FunctionType>();
2811 AdjustedType = Context.adjustFunctionType(AdjustedType, NewTypeInfo);
2812 New->setType(QualType(AdjustedType, 0));
2813 NewQType = Context.getCanonicalType(New->getType());
2814 NewType = cast<FunctionType>(NewQType);
2817 // If this redeclaration makes the function inline, we may need to add it to
2818 // UndefinedButUsed.
2819 if (!Old->isInlined() && New->isInlined() &&
2820 !New->hasAttr<GNUInlineAttr>() &&
2821 !getLangOpts().GNUInline &&
2822 Old->isUsed(false) &&
2823 !Old->isDefined() && !New->isThisDeclarationADefinition())
2824 UndefinedButUsed.insert(std::make_pair(Old->getCanonicalDecl(),
2827 // If this redeclaration makes it newly gnu_inline, we don't want to warn
2829 if (New->hasAttr<GNUInlineAttr>() &&
2830 Old->isInlined() && !Old->hasAttr<GNUInlineAttr>()) {
2831 UndefinedButUsed.erase(Old->getCanonicalDecl());
2834 // If pass_object_size params don't match up perfectly, this isn't a valid
2836 if (Old->getNumParams() > 0 && Old->getNumParams() == New->getNumParams() &&
2837 !hasIdenticalPassObjectSizeAttrs(Old, New)) {
2838 Diag(New->getLocation(), diag::err_different_pass_object_size_params)
2839 << New->getDeclName();
2840 Diag(OldLocation, PrevDiag) << Old << Old->getType();
2844 if (getLangOpts().CPlusPlus) {
2846 // Certain function declarations cannot be overloaded:
2847 // -- Function declarations that differ only in the return type
2848 // cannot be overloaded.
2850 // Go back to the type source info to compare the declared return types,
2851 // per C++1y [dcl.type.auto]p13:
2852 // Redeclarations or specializations of a function or function template
2853 // with a declared return type that uses a placeholder type shall also
2854 // use that placeholder, not a deduced type.
2855 QualType OldDeclaredReturnType =
2856 (Old->getTypeSourceInfo()
2857 ? Old->getTypeSourceInfo()->getType()->castAs<FunctionType>()
2858 : OldType)->getReturnType();
2859 QualType NewDeclaredReturnType =
2860 (New->getTypeSourceInfo()
2861 ? New->getTypeSourceInfo()->getType()->castAs<FunctionType>()
2862 : NewType)->getReturnType();
2864 if (!Context.hasSameType(OldDeclaredReturnType, NewDeclaredReturnType) &&
2865 !((NewQType->isDependentType() || OldQType->isDependentType()) &&
2866 New->isLocalExternDecl())) {
2867 if (NewDeclaredReturnType->isObjCObjectPointerType() &&
2868 OldDeclaredReturnType->isObjCObjectPointerType())
2869 ResQT = Context.mergeObjCGCQualifiers(NewQType, OldQType);
2870 if (ResQT.isNull()) {
2871 if (New->isCXXClassMember() && New->isOutOfLine())
2872 Diag(New->getLocation(), diag::err_member_def_does_not_match_ret_type)
2873 << New << New->getReturnTypeSourceRange();
2875 Diag(New->getLocation(), diag::err_ovl_diff_return_type)
2876 << New->getReturnTypeSourceRange();
2877 Diag(OldLocation, PrevDiag) << Old << Old->getType()
2878 << Old->getReturnTypeSourceRange();
2885 QualType OldReturnType = OldType->getReturnType();
2886 QualType NewReturnType = cast<FunctionType>(NewQType)->getReturnType();
2887 if (OldReturnType != NewReturnType) {
2888 // If this function has a deduced return type and has already been
2889 // defined, copy the deduced value from the old declaration.
2890 AutoType *OldAT = Old->getReturnType()->getContainedAutoType();
2891 if (OldAT && OldAT->isDeduced()) {
2893 SubstAutoType(New->getType(),
2894 OldAT->isDependentType() ? Context.DependentTy
2895 : OldAT->getDeducedType()));
2896 NewQType = Context.getCanonicalType(
2897 SubstAutoType(NewQType,
2898 OldAT->isDependentType() ? Context.DependentTy
2899 : OldAT->getDeducedType()));
2903 const CXXMethodDecl *OldMethod = dyn_cast<CXXMethodDecl>(Old);
2904 CXXMethodDecl *NewMethod = dyn_cast<CXXMethodDecl>(New);
2905 if (OldMethod && NewMethod) {
2906 // Preserve triviality.
2907 NewMethod->setTrivial(OldMethod->isTrivial());
2909 // MSVC allows explicit template specialization at class scope:
2910 // 2 CXXMethodDecls referring to the same function will be injected.
2911 // We don't want a redeclaration error.
2912 bool IsClassScopeExplicitSpecialization =
2913 OldMethod->isFunctionTemplateSpecialization() &&
2914 NewMethod->isFunctionTemplateSpecialization();
2915 bool isFriend = NewMethod->getFriendObjectKind();
2917 if (!isFriend && NewMethod->getLexicalDeclContext()->isRecord() &&
2918 !IsClassScopeExplicitSpecialization) {
2919 // -- Member function declarations with the same name and the
2920 // same parameter types cannot be overloaded if any of them
2921 // is a static member function declaration.
2922 if (OldMethod->isStatic() != NewMethod->isStatic()) {
2923 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member);
2924 Diag(OldLocation, PrevDiag) << Old << Old->getType();
2928 // C++ [class.mem]p1:
2929 // [...] A member shall not be declared twice in the
2930 // member-specification, except that a nested class or member
2931 // class template can be declared and then later defined.
2932 if (ActiveTemplateInstantiations.empty()) {
2934 if (isa<CXXConstructorDecl>(OldMethod))
2935 NewDiag = diag::err_constructor_redeclared;
2936 else if (isa<CXXDestructorDecl>(NewMethod))
2937 NewDiag = diag::err_destructor_redeclared;
2938 else if (isa<CXXConversionDecl>(NewMethod))
2939 NewDiag = diag::err_conv_function_redeclared;
2941 NewDiag = diag::err_member_redeclared;
2943 Diag(New->getLocation(), NewDiag);
2945 Diag(New->getLocation(), diag::err_member_redeclared_in_instantiation)
2946 << New << New->getType();
2948 Diag(OldLocation, PrevDiag) << Old << Old->getType();
2951 // Complain if this is an explicit declaration of a special
2952 // member that was initially declared implicitly.
2954 // As an exception, it's okay to befriend such methods in order
2955 // to permit the implicit constructor/destructor/operator calls.
2956 } else if (OldMethod->isImplicit()) {
2958 NewMethod->setImplicit();
2960 Diag(NewMethod->getLocation(),
2961 diag::err_definition_of_implicitly_declared_member)
2962 << New << getSpecialMember(OldMethod);
2965 } else if (OldMethod->isExplicitlyDefaulted() && !isFriend) {
2966 Diag(NewMethod->getLocation(),
2967 diag::err_definition_of_explicitly_defaulted_member)
2968 << getSpecialMember(OldMethod);
2973 // C++11 [dcl.attr.noreturn]p1:
2974 // The first declaration of a function shall specify the noreturn
2975 // attribute if any declaration of that function specifies the noreturn
2977 const CXX11NoReturnAttr *NRA = New->getAttr<CXX11NoReturnAttr>();
2978 if (NRA && !Old->hasAttr<CXX11NoReturnAttr>()) {
2979 Diag(NRA->getLocation(), diag::err_noreturn_missing_on_first_decl);
2980 Diag(Old->getFirstDecl()->getLocation(),
2981 diag::note_noreturn_missing_first_decl);
2984 // C++11 [dcl.attr.depend]p2:
2985 // The first declaration of a function shall specify the
2986 // carries_dependency attribute for its declarator-id if any declaration
2987 // of the function specifies the carries_dependency attribute.
2988 const CarriesDependencyAttr *CDA = New->getAttr<CarriesDependencyAttr>();
2989 if (CDA && !Old->hasAttr<CarriesDependencyAttr>()) {
2990 Diag(CDA->getLocation(),
2991 diag::err_carries_dependency_missing_on_first_decl) << 0/*Function*/;
2992 Diag(Old->getFirstDecl()->getLocation(),
2993 diag::note_carries_dependency_missing_first_decl) << 0/*Function*/;
2997 // All declarations for a function shall agree exactly in both the
2998 // return type and the parameter-type-list.
2999 // We also want to respect all the extended bits except noreturn.
3001 // noreturn should now match unless the old type info didn't have it.
3002 QualType OldQTypeForComparison = OldQType;
3003 if (!OldTypeInfo.getNoReturn() && NewTypeInfo.getNoReturn()) {
3004 assert(OldQType == QualType(OldType, 0));
3005 const FunctionType *OldTypeForComparison
3006 = Context.adjustFunctionType(OldType, OldTypeInfo.withNoReturn(true));
3007 OldQTypeForComparison = QualType(OldTypeForComparison, 0);
3008 assert(OldQTypeForComparison.isCanonical());
3011 if (haveIncompatibleLanguageLinkages(Old, New)) {
3012 // As a special case, retain the language linkage from previous
3013 // declarations of a friend function as an extension.
3015 // This liberal interpretation of C++ [class.friend]p3 matches GCC/MSVC
3016 // and is useful because there's otherwise no way to specify language
3017 // linkage within class scope.
3019 // Check cautiously as the friend object kind isn't yet complete.
3020 if (New->getFriendObjectKind() != Decl::FOK_None) {
3021 Diag(New->getLocation(), diag::ext_retained_language_linkage) << New;
3022 Diag(OldLocation, PrevDiag);
3024 Diag(New->getLocation(), diag::err_different_language_linkage) << New;
3025 Diag(OldLocation, PrevDiag);
3030 if (OldQTypeForComparison == NewQType)
3031 return MergeCompatibleFunctionDecls(New, Old, S, MergeTypeWithOld);
3033 if ((NewQType->isDependentType() || OldQType->isDependentType()) &&
3034 New->isLocalExternDecl()) {
3035 // It's OK if we couldn't merge types for a local function declaraton
3036 // if either the old or new type is dependent. We'll merge the types
3037 // when we instantiate the function.
3041 // Fall through for conflicting redeclarations and redefinitions.
3044 // C: Function types need to be compatible, not identical. This handles
3045 // duplicate function decls like "void f(int); void f(enum X);" properly.
3046 if (!getLangOpts().CPlusPlus &&
3047 Context.typesAreCompatible(OldQType, NewQType)) {
3048 const FunctionType *OldFuncType = OldQType->getAs<FunctionType>();
3049 const FunctionType *NewFuncType = NewQType->getAs<FunctionType>();
3050 const FunctionProtoType *OldProto = nullptr;
3051 if (MergeTypeWithOld && isa<FunctionNoProtoType>(NewFuncType) &&
3052 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) {
3053 // The old declaration provided a function prototype, but the
3054 // new declaration does not. Merge in the prototype.
3055 assert(!OldProto->hasExceptionSpec() && "Exception spec in C");
3056 SmallVector<QualType, 16> ParamTypes(OldProto->param_types());
3058 Context.getFunctionType(NewFuncType->getReturnType(), ParamTypes,
3059 OldProto->getExtProtoInfo());
3060 New->setType(NewQType);
3061 New->setHasInheritedPrototype();
3063 // Synthesize parameters with the same types.
3064 SmallVector<ParmVarDecl*, 16> Params;
3065 for (const auto &ParamType : OldProto->param_types()) {
3066 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, SourceLocation(),
3067 SourceLocation(), nullptr,
3068 ParamType, /*TInfo=*/nullptr,
3070 Param->setScopeInfo(0, Params.size());
3071 Param->setImplicit();
3072 Params.push_back(Param);
3075 New->setParams(Params);
3078 return MergeCompatibleFunctionDecls(New, Old, S, MergeTypeWithOld);
3081 // GNU C permits a K&R definition to follow a prototype declaration
3082 // if the declared types of the parameters in the K&R definition
3083 // match the types in the prototype declaration, even when the
3084 // promoted types of the parameters from the K&R definition differ
3085 // from the types in the prototype. GCC then keeps the types from
3088 // If a variadic prototype is followed by a non-variadic K&R definition,
3089 // the K&R definition becomes variadic. This is sort of an edge case, but
3090 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and
3092 if (!getLangOpts().CPlusPlus &&
3093 Old->hasPrototype() && !New->hasPrototype() &&
3094 New->getType()->getAs<FunctionProtoType>() &&
3095 Old->getNumParams() == New->getNumParams()) {
3096 SmallVector<QualType, 16> ArgTypes;
3097 SmallVector<GNUCompatibleParamWarning, 16> Warnings;
3098 const FunctionProtoType *OldProto
3099 = Old->getType()->getAs<FunctionProtoType>();
3100 const FunctionProtoType *NewProto
3101 = New->getType()->getAs<FunctionProtoType>();
3103 // Determine whether this is the GNU C extension.
3104 QualType MergedReturn = Context.mergeTypes(OldProto->getReturnType(),
3105 NewProto->getReturnType());
3106 bool LooseCompatible = !MergedReturn.isNull();
3107 for (unsigned Idx = 0, End = Old->getNumParams();
3108 LooseCompatible && Idx != End; ++Idx) {
3109 ParmVarDecl *OldParm = Old->getParamDecl(Idx);
3110 ParmVarDecl *NewParm = New->getParamDecl(Idx);
3111 if (Context.typesAreCompatible(OldParm->getType(),
3112 NewProto->getParamType(Idx))) {
3113 ArgTypes.push_back(NewParm->getType());
3114 } else if (Context.typesAreCompatible(OldParm->getType(),
3116 /*CompareUnqualified=*/true)) {
3117 GNUCompatibleParamWarning Warn = { OldParm, NewParm,
3118 NewProto->getParamType(Idx) };
3119 Warnings.push_back(Warn);
3120 ArgTypes.push_back(NewParm->getType());
3122 LooseCompatible = false;
3125 if (LooseCompatible) {
3126 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) {
3127 Diag(Warnings[Warn].NewParm->getLocation(),
3128 diag::ext_param_promoted_not_compatible_with_prototype)
3129 << Warnings[Warn].PromotedType
3130 << Warnings[Warn].OldParm->getType();
3131 if (Warnings[Warn].OldParm->getLocation().isValid())
3132 Diag(Warnings[Warn].OldParm->getLocation(),
3133 diag::note_previous_declaration);
3136 if (MergeTypeWithOld)
3137 New->setType(Context.getFunctionType(MergedReturn, ArgTypes,
3138 OldProto->getExtProtoInfo()));
3139 return MergeCompatibleFunctionDecls(New, Old, S, MergeTypeWithOld);
3142 // Fall through to diagnose conflicting types.
3145 // A function that has already been declared has been redeclared or
3146 // defined with a different type; show an appropriate diagnostic.
3148 // If the previous declaration was an implicitly-generated builtin
3149 // declaration, then at the very least we should use a specialized note.
3151 if (Old->isImplicit() && (BuiltinID = Old->getBuiltinID())) {
3152 // If it's actually a library-defined builtin function like 'malloc'
3153 // or 'printf', just warn about the incompatible redeclaration.
3154 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) {
3155 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New;
3156 Diag(OldLocation, diag::note_previous_builtin_declaration)
3157 << Old << Old->getType();
3159 // If this is a global redeclaration, just forget hereafter
3160 // about the "builtin-ness" of the function.
3162 // Doing this for local extern declarations is problematic. If
3163 // the builtin declaration remains visible, a second invalid
3164 // local declaration will produce a hard error; if it doesn't
3165 // remain visible, a single bogus local redeclaration (which is
3166 // actually only a warning) could break all the downstream code.
3167 if (!New->getLexicalDeclContext()->isFunctionOrMethod())
3168 New->getIdentifier()->revertBuiltin();
3173 PrevDiag = diag::note_previous_builtin_declaration;
3176 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName();
3177 Diag(OldLocation, PrevDiag) << Old << Old->getType();
3181 /// \brief Completes the merge of two function declarations that are
3182 /// known to be compatible.
3184 /// This routine handles the merging of attributes and other
3185 /// properties of function declarations from the old declaration to
3186 /// the new declaration, once we know that New is in fact a
3187 /// redeclaration of Old.
3190 bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old,
3191 Scope *S, bool MergeTypeWithOld) {
3192 // Merge the attributes
3193 mergeDeclAttributes(New, Old);
3195 // Merge "pure" flag.
3199 // Merge "used" flag.
3200 if (Old->getMostRecentDecl()->isUsed(false))
3203 // Merge attributes from the parameters. These can mismatch with K&R
3205 if (New->getNumParams() == Old->getNumParams())
3206 for (unsigned i = 0, e = New->getNumParams(); i != e; ++i) {
3207 ParmVarDecl *NewParam = New->getParamDecl(i);
3208 ParmVarDecl *OldParam = Old->getParamDecl(i);
3209 mergeParamDeclAttributes(NewParam, OldParam, *this);
3210 mergeParamDeclTypes(NewParam, OldParam, *this);
3213 if (getLangOpts().CPlusPlus)
3214 return MergeCXXFunctionDecl(New, Old, S);
3216 // Merge the function types so the we get the composite types for the return
3217 // and argument types. Per C11 6.2.7/4, only update the type if the old decl
3219 QualType Merged = Context.mergeTypes(Old->getType(), New->getType());
3220 if (!Merged.isNull() && MergeTypeWithOld)
3221 New->setType(Merged);
3226 void Sema::mergeObjCMethodDecls(ObjCMethodDecl *newMethod,
3227 ObjCMethodDecl *oldMethod) {
3228 // Merge the attributes, including deprecated/unavailable
3229 AvailabilityMergeKind MergeKind =
3230 isa<ObjCProtocolDecl>(oldMethod->getDeclContext())
3231 ? AMK_ProtocolImplementation
3232 : isa<ObjCImplDecl>(newMethod->getDeclContext()) ? AMK_Redeclaration
3235 mergeDeclAttributes(newMethod, oldMethod, MergeKind);
3237 // Merge attributes from the parameters.
3238 ObjCMethodDecl::param_const_iterator oi = oldMethod->param_begin(),
3239 oe = oldMethod->param_end();
3240 for (ObjCMethodDecl::param_iterator
3241 ni = newMethod->param_begin(), ne = newMethod->param_end();
3242 ni != ne && oi != oe; ++ni, ++oi)
3243 mergeParamDeclAttributes(*ni, *oi, *this);
3245 CheckObjCMethodOverride(newMethod, oldMethod);
3248 /// MergeVarDeclTypes - We parsed a variable 'New' which has the same name and
3249 /// scope as a previous declaration 'Old'. Figure out how to merge their types,
3250 /// emitting diagnostics as appropriate.
3252 /// Declarations using the auto type specifier (C++ [decl.spec.auto]) call back
3253 /// to here in AddInitializerToDecl. We can't check them before the initializer
3255 void Sema::MergeVarDeclTypes(VarDecl *New, VarDecl *Old,
3256 bool MergeTypeWithOld) {
3257 if (New->isInvalidDecl() || Old->isInvalidDecl())
3261 if (getLangOpts().CPlusPlus) {
3262 if (New->getType()->isUndeducedType()) {
3263 // We don't know what the new type is until the initializer is attached.
3265 } else if (Context.hasSameType(New->getType(), Old->getType())) {
3266 // These could still be something that needs exception specs checked.
3267 return MergeVarDeclExceptionSpecs(New, Old);
3269 // C++ [basic.link]p10:
3270 // [...] the types specified by all declarations referring to a given
3271 // object or function shall be identical, except that declarations for an
3272 // array object can specify array types that differ by the presence or
3273 // absence of a major array bound (8.3.4).
3274 else if (Old->getType()->isIncompleteArrayType() &&
3275 New->getType()->isArrayType()) {
3276 const ArrayType *OldArray = Context.getAsArrayType(Old->getType());
3277 const ArrayType *NewArray = Context.getAsArrayType(New->getType());
3278 if (Context.hasSameType(OldArray->getElementType(),
3279 NewArray->getElementType()))
3280 MergedT = New->getType();
3281 } else if (Old->getType()->isArrayType() &&
3282 New->getType()->isIncompleteArrayType()) {
3283 const ArrayType *OldArray = Context.getAsArrayType(Old->getType());
3284 const ArrayType *NewArray = Context.getAsArrayType(New->getType());
3285 if (Context.hasSameType(OldArray->getElementType(),
3286 NewArray->getElementType()))
3287 MergedT = Old->getType();
3288 } else if (New->getType()->isObjCObjectPointerType() &&
3289 Old->getType()->isObjCObjectPointerType()) {
3290 MergedT = Context.mergeObjCGCQualifiers(New->getType(),
3295 // All declarations that refer to the same object or function shall have
3297 MergedT = Context.mergeTypes(New->getType(), Old->getType());
3299 if (MergedT.isNull()) {
3300 // It's OK if we couldn't merge types if either type is dependent, for a
3301 // block-scope variable. In other cases (static data members of class
3302 // templates, variable templates, ...), we require the types to be
3304 // FIXME: The C++ standard doesn't say anything about this.
3305 if ((New->getType()->isDependentType() ||
3306 Old->getType()->isDependentType()) && New->isLocalVarDecl()) {
3307 // If the old type was dependent, we can't merge with it, so the new type
3308 // becomes dependent for now. We'll reproduce the original type when we
3309 // instantiate the TypeSourceInfo for the variable.
3310 if (!New->getType()->isDependentType() && MergeTypeWithOld)
3311 New->setType(Context.DependentTy);
3315 // FIXME: Even if this merging succeeds, some other non-visible declaration
3316 // of this variable might have an incompatible type. For instance:
3318 // extern int arr[];
3319 // void f() { extern int arr[2]; }
3320 // void g() { extern int arr[3]; }
3322 // Neither C nor C++ requires a diagnostic for this, but we should still try
3324 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 Diag(OldLocation, PrevDiag);
3334 return New->setInvalidDecl();
3337 // Don't actually update the type on the new declaration if the old
3338 // declaration was an extern declaration in a different scope.
3339 if (MergeTypeWithOld)
3340 New->setType(MergedT);
3343 static bool mergeTypeWithPrevious(Sema &S, VarDecl *NewVD, VarDecl *OldVD,
3344 LookupResult &Previous) {
3346 // For an identifier with internal or external linkage declared
3347 // in a scope in which a prior declaration of that identifier is
3348 // visible, if the prior declaration specifies internal or
3349 // external linkage, the type of the identifier at the later
3350 // declaration becomes the composite type.
3352 // If the variable isn't visible, we do not merge with its type.
3353 if (Previous.isShadowed())
3356 if (S.getLangOpts().CPlusPlus) {
3357 // C++11 [dcl.array]p3:
3358 // If there is a preceding declaration of the entity in the same
3359 // scope in which the bound was specified, an omitted array bound
3360 // is taken to be the same as in that earlier declaration.
3361 return NewVD->isPreviousDeclInSameBlockScope() ||
3362 (!OldVD->getLexicalDeclContext()->isFunctionOrMethod() &&
3363 !NewVD->getLexicalDeclContext()->isFunctionOrMethod());
3365 // If the old declaration was function-local, don't merge with its
3366 // type unless we're in the same function.
3367 return !OldVD->getLexicalDeclContext()->isFunctionOrMethod() ||
3368 OldVD->getLexicalDeclContext() == NewVD->getLexicalDeclContext();
3372 /// MergeVarDecl - We just parsed a variable 'New' which has the same name
3373 /// and scope as a previous declaration 'Old'. Figure out how to resolve this
3374 /// situation, merging decls or emitting diagnostics as appropriate.
3376 /// Tentative definition rules (C99 6.9.2p2) are checked by
3377 /// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative
3378 /// definitions here, since the initializer hasn't been attached.
3380 void Sema::MergeVarDecl(VarDecl *New, LookupResult &Previous) {
3381 // If the new decl is already invalid, don't do any other checking.
3382 if (New->isInvalidDecl())
3385 if (!shouldLinkPossiblyHiddenDecl(Previous, New))
3388 VarTemplateDecl *NewTemplate = New->getDescribedVarTemplate();
3390 // Verify the old decl was also a variable or variable template.
3391 VarDecl *Old = nullptr;
3392 VarTemplateDecl *OldTemplate = nullptr;
3393 if (Previous.isSingleResult()) {
3395 OldTemplate = dyn_cast<VarTemplateDecl>(Previous.getFoundDecl());
3396 Old = OldTemplate ? OldTemplate->getTemplatedDecl() : nullptr;
3399 dyn_cast<UsingShadowDecl>(Previous.getRepresentativeDecl()))
3400 if (checkUsingShadowRedecl<VarTemplateDecl>(*this, Shadow, NewTemplate))
3401 return New->setInvalidDecl();
3403 Old = dyn_cast<VarDecl>(Previous.getFoundDecl());
3406 dyn_cast<UsingShadowDecl>(Previous.getRepresentativeDecl()))
3407 if (checkUsingShadowRedecl<VarDecl>(*this, Shadow, New))
3408 return New->setInvalidDecl();
3412 Diag(New->getLocation(), diag::err_redefinition_different_kind)
3413 << New->getDeclName();
3414 Diag(Previous.getRepresentativeDecl()->getLocation(),
3415 diag::note_previous_definition);
3416 return New->setInvalidDecl();
3419 // Ensure the template parameters are compatible.
3421 !TemplateParameterListsAreEqual(NewTemplate->getTemplateParameters(),
3422 OldTemplate->getTemplateParameters(),
3423 /*Complain=*/true, TPL_TemplateMatch))
3424 return New->setInvalidDecl();
3426 // C++ [class.mem]p1:
3427 // A member shall not be declared twice in the member-specification [...]
3429 // Here, we need only consider static data members.
3430 if (Old->isStaticDataMember() && !New->isOutOfLine()) {
3431 Diag(New->getLocation(), diag::err_duplicate_member)
3432 << New->getIdentifier();
3433 Diag(Old->getLocation(), diag::note_previous_declaration);
3434 New->setInvalidDecl();
3437 mergeDeclAttributes(New, Old);
3438 // Warn if an already-declared variable is made a weak_import in a subsequent
3440 if (New->hasAttr<WeakImportAttr>() &&
3441 Old->getStorageClass() == SC_None &&
3442 !Old->hasAttr<WeakImportAttr>()) {
3443 Diag(New->getLocation(), diag::warn_weak_import) << New->getDeclName();
3444 Diag(Old->getLocation(), diag::note_previous_definition);
3445 // Remove weak_import attribute on new declaration.
3446 New->dropAttr<WeakImportAttr>();
3449 if (New->hasAttr<InternalLinkageAttr>() &&
3450 !Old->hasAttr<InternalLinkageAttr>()) {
3451 Diag(New->getLocation(), diag::err_internal_linkage_redeclaration)
3452 << New->getDeclName();
3453 Diag(Old->getLocation(), diag::note_previous_definition);
3454 New->dropAttr<InternalLinkageAttr>();
3458 VarDecl *MostRecent = Old->getMostRecentDecl();
3459 if (MostRecent != Old) {
3460 MergeVarDeclTypes(New, MostRecent,
3461 mergeTypeWithPrevious(*this, New, MostRecent, Previous));
3462 if (New->isInvalidDecl())
3466 MergeVarDeclTypes(New, Old, mergeTypeWithPrevious(*this, New, Old, Previous));
3467 if (New->isInvalidDecl())
3470 diag::kind PrevDiag;
3471 SourceLocation OldLocation;
3472 std::tie(PrevDiag, OldLocation) =
3473 getNoteDiagForInvalidRedeclaration(Old, New);
3475 // [dcl.stc]p8: Check if we have a non-static decl followed by a static.
3476 if (New->getStorageClass() == SC_Static &&
3477 !New->isStaticDataMember() &&
3478 Old->hasExternalFormalLinkage()) {
3479 if (getLangOpts().MicrosoftExt) {
3480 Diag(New->getLocation(), diag::ext_static_non_static)
3481 << New->getDeclName();
3482 Diag(OldLocation, PrevDiag);
3484 Diag(New->getLocation(), diag::err_static_non_static)
3485 << New->getDeclName();
3486 Diag(OldLocation, PrevDiag);
3487 return New->setInvalidDecl();
3491 // For an identifier declared with the storage-class specifier
3492 // extern in a scope in which a prior declaration of that
3493 // identifier is visible,23) if the prior declaration specifies
3494 // internal or external linkage, the linkage of the identifier at
3495 // the later declaration is the same as the linkage specified at
3496 // the prior declaration. If no prior declaration is visible, or
3497 // if the prior declaration specifies no linkage, then the
3498 // identifier has external linkage.
3499 if (New->hasExternalStorage() && Old->hasLinkage())
3501 else if (New->getCanonicalDecl()->getStorageClass() != SC_Static &&
3502 !New->isStaticDataMember() &&
3503 Old->getCanonicalDecl()->getStorageClass() == SC_Static) {
3504 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName();
3505 Diag(OldLocation, PrevDiag);
3506 return New->setInvalidDecl();
3509 // Check if extern is followed by non-extern and vice-versa.
3510 if (New->hasExternalStorage() &&
3511 !Old->hasLinkage() && Old->isLocalVarDeclOrParm()) {
3512 Diag(New->getLocation(), diag::err_extern_non_extern) << New->getDeclName();
3513 Diag(OldLocation, PrevDiag);
3514 return New->setInvalidDecl();
3516 if (Old->hasLinkage() && New->isLocalVarDeclOrParm() &&
3517 !New->hasExternalStorage()) {
3518 Diag(New->getLocation(), diag::err_non_extern_extern) << New->getDeclName();
3519 Diag(OldLocation, PrevDiag);
3520 return New->setInvalidDecl();
3523 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup.
3525 // FIXME: The test for external storage here seems wrong? We still
3526 // need to check for mismatches.
3527 if (!New->hasExternalStorage() && !New->isFileVarDecl() &&
3528 // Don't complain about out-of-line definitions of static members.
3529 !(Old->getLexicalDeclContext()->isRecord() &&
3530 !New->getLexicalDeclContext()->isRecord())) {
3531 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName();
3532 Diag(OldLocation, PrevDiag);
3533 return New->setInvalidDecl();
3536 if (New->getTLSKind() != Old->getTLSKind()) {
3537 if (!Old->getTLSKind()) {
3538 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName();
3539 Diag(OldLocation, PrevDiag);
3540 } else if (!New->getTLSKind()) {
3541 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName();
3542 Diag(OldLocation, PrevDiag);
3544 // Do not allow redeclaration to change the variable between requiring
3545 // static and dynamic initialization.
3546 // FIXME: GCC allows this, but uses the TLS keyword on the first
3547 // declaration to determine the kind. Do we need to be compatible here?
3548 Diag(New->getLocation(), diag::err_thread_thread_different_kind)
3549 << New->getDeclName() << (New->getTLSKind() == VarDecl::TLS_Dynamic);
3550 Diag(OldLocation, PrevDiag);
3554 // C++ doesn't have tentative definitions, so go right ahead and check here.
3556 if (getLangOpts().CPlusPlus &&
3557 New->isThisDeclarationADefinition() == VarDecl::Definition &&
3558 (Def = Old->getDefinition())) {
3559 NamedDecl *Hidden = nullptr;
3560 if (!hasVisibleDefinition(Def, &Hidden) &&
3561 (New->getFormalLinkage() == InternalLinkage ||
3562 New->getDescribedVarTemplate() ||
3563 New->getNumTemplateParameterLists() ||
3564 New->getDeclContext()->isDependentContext())) {
3565 // The previous definition is hidden, and multiple definitions are
3566 // permitted (in separate TUs). Form another definition of it.
3568 Diag(New->getLocation(), diag::err_redefinition) << New;
3569 Diag(Def->getLocation(), diag::note_previous_definition);
3570 New->setInvalidDecl();
3575 if (haveIncompatibleLanguageLinkages(Old, New)) {
3576 Diag(New->getLocation(), diag::err_different_language_linkage) << New;
3577 Diag(OldLocation, PrevDiag);
3578 New->setInvalidDecl();
3582 // Merge "used" flag.
3583 if (Old->getMostRecentDecl()->isUsed(false))
3586 // Keep a chain of previous declarations.
3587 New->setPreviousDecl(Old);
3589 NewTemplate->setPreviousDecl(OldTemplate);
3591 // Inherit access appropriately.
3592 New->setAccess(Old->getAccess());
3594 NewTemplate->setAccess(New->getAccess());
3597 /// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with
3598 /// no declarator (e.g. "struct foo;") is parsed.
3600 Sema::ParsedFreeStandingDeclSpec(Scope *S, AccessSpecifier AS, DeclSpec &DS,
3601 RecordDecl *&AnonRecord) {
3602 return ParsedFreeStandingDeclSpec(S, AS, DS, MultiTemplateParamsArg(), false,
3606 // The MS ABI changed between VS2013 and VS2015 with regard to numbers used to
3607 // disambiguate entities defined in different scopes.
3608 // While the VS2015 ABI fixes potential miscompiles, it is also breaks
3610 // We will pick our mangling number depending on which version of MSVC is being
3612 static unsigned getMSManglingNumber(const LangOptions &LO, Scope *S) {
3613 return LO.isCompatibleWithMSVC(LangOptions::MSVC2015)
3614 ? S->getMSCurManglingNumber()
3615 : S->getMSLastManglingNumber();
3618 void Sema::handleTagNumbering(const TagDecl *Tag, Scope *TagScope) {
3619 if (!Context.getLangOpts().CPlusPlus)
3622 if (isa<CXXRecordDecl>(Tag->getParent())) {
3623 // If this tag is the direct child of a class, number it if
3625 if (!Tag->getName().empty() || Tag->getTypedefNameForAnonDecl())
3627 MangleNumberingContext &MCtx =
3628 Context.getManglingNumberContext(Tag->getParent());
3629 Context.setManglingNumber(
3630 Tag, MCtx.getManglingNumber(
3631 Tag, getMSManglingNumber(getLangOpts(), TagScope)));
3635 // If this tag isn't a direct child of a class, number it if it is local.
3636 Decl *ManglingContextDecl;
3637 if (MangleNumberingContext *MCtx = getCurrentMangleNumberContext(
3638 Tag->getDeclContext(), ManglingContextDecl)) {
3639 Context.setManglingNumber(
3640 Tag, MCtx->getManglingNumber(
3641 Tag, getMSManglingNumber(getLangOpts(), TagScope)));
3645 void Sema::setTagNameForLinkagePurposes(TagDecl *TagFromDeclSpec,
3646 TypedefNameDecl *NewTD) {
3647 if (TagFromDeclSpec->isInvalidDecl())
3650 // Do nothing if the tag already has a name for linkage purposes.
3651 if (TagFromDeclSpec->hasNameForLinkage())
3654 // A well-formed anonymous tag must always be a TUK_Definition.
3655 assert(TagFromDeclSpec->isThisDeclarationADefinition());
3657 // The type must match the tag exactly; no qualifiers allowed.
3658 if (!Context.hasSameType(NewTD->getUnderlyingType(),
3659 Context.getTagDeclType(TagFromDeclSpec))) {
3660 if (getLangOpts().CPlusPlus)
3661 Context.addTypedefNameForUnnamedTagDecl(TagFromDeclSpec, NewTD);
3665 // If we've already computed linkage for the anonymous tag, then
3666 // adding a typedef name for the anonymous decl can change that
3667 // linkage, which might be a serious problem. Diagnose this as
3668 // unsupported and ignore the typedef name. TODO: we should
3669 // pursue this as a language defect and establish a formal rule
3670 // for how to handle it.
3671 if (TagFromDeclSpec->hasLinkageBeenComputed()) {
3672 Diag(NewTD->getLocation(), diag::err_typedef_changes_linkage);
3674 SourceLocation tagLoc = TagFromDeclSpec->getInnerLocStart();
3675 tagLoc = getLocForEndOfToken(tagLoc);
3677 llvm::SmallString<40> textToInsert;
3678 textToInsert += ' ';
3679 textToInsert += NewTD->getIdentifier()->getName();
3680 Diag(tagLoc, diag::note_typedef_changes_linkage)
3681 << FixItHint::CreateInsertion(tagLoc, textToInsert);
3685 // Otherwise, set this is the anon-decl typedef for the tag.
3686 TagFromDeclSpec->setTypedefNameForAnonDecl(NewTD);
3689 static unsigned GetDiagnosticTypeSpecifierID(DeclSpec::TST T) {
3691 case DeclSpec::TST_class:
3693 case DeclSpec::TST_struct:
3695 case DeclSpec::TST_interface:
3697 case DeclSpec::TST_union:
3699 case DeclSpec::TST_enum:
3702 llvm_unreachable("unexpected type specifier");
3706 /// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with
3707 /// no declarator (e.g. "struct foo;") is parsed. It also accepts template
3708 /// parameters to cope with template friend declarations.
3710 Sema::ParsedFreeStandingDeclSpec(Scope *S, AccessSpecifier AS, DeclSpec &DS,
3711 MultiTemplateParamsArg TemplateParams,
3712 bool IsExplicitInstantiation,
3713 RecordDecl *&AnonRecord) {
3714 Decl *TagD = nullptr;
3715 TagDecl *Tag = nullptr;
3716 if (DS.getTypeSpecType() == DeclSpec::TST_class ||
3717 DS.getTypeSpecType() == DeclSpec::TST_struct ||
3718 DS.getTypeSpecType() == DeclSpec::TST_interface ||
3719 DS.getTypeSpecType() == DeclSpec::TST_union ||
3720 DS.getTypeSpecType() == DeclSpec::TST_enum) {
3721 TagD = DS.getRepAsDecl();
3723 if (!TagD) // We probably had an error
3726 // Note that the above type specs guarantee that the
3727 // type rep is a Decl, whereas in many of the others
3729 if (isa<TagDecl>(TagD))
3730 Tag = cast<TagDecl>(TagD);
3731 else if (ClassTemplateDecl *CTD = dyn_cast<ClassTemplateDecl>(TagD))
3732 Tag = CTD->getTemplatedDecl();
3736 handleTagNumbering(Tag, S);
3737 Tag->setFreeStanding();
3738 if (Tag->isInvalidDecl())
3742 if (unsigned TypeQuals = DS.getTypeQualifiers()) {
3743 // Enforce C99 6.7.3p2: "Types other than pointer types derived from object
3744 // or incomplete types shall not be restrict-qualified."
3745 if (TypeQuals & DeclSpec::TQ_restrict)
3746 Diag(DS.getRestrictSpecLoc(),
3747 diag::err_typecheck_invalid_restrict_not_pointer_noarg)
3748 << DS.getSourceRange();
3751 if (DS.isConstexprSpecified()) {
3752 // C++0x [dcl.constexpr]p1: constexpr can only be applied to declarations
3753 // and definitions of functions and variables.
3755 Diag(DS.getConstexprSpecLoc(), diag::err_constexpr_tag)
3756 << GetDiagnosticTypeSpecifierID(DS.getTypeSpecType());
3758 Diag(DS.getConstexprSpecLoc(), diag::err_constexpr_no_declarators);
3759 // Don't emit warnings after this error.
3763 if (DS.isConceptSpecified()) {
3764 // C++ Concepts TS [dcl.spec.concept]p1: A concept definition refers to
3765 // either a function concept and its definition or a variable concept and
3767 Diag(DS.getConceptSpecLoc(), diag::err_concept_wrong_decl_kind);
3771 DiagnoseFunctionSpecifiers(DS);
3773 if (DS.isFriendSpecified()) {
3774 // If we're dealing with a decl but not a TagDecl, assume that
3775 // whatever routines created it handled the friendship aspect.
3778 return ActOnFriendTypeDecl(S, DS, TemplateParams);
3781 const CXXScopeSpec &SS = DS.getTypeSpecScope();
3782 bool IsExplicitSpecialization =
3783 !TemplateParams.empty() && TemplateParams.back()->size() == 0;
3784 if (Tag && SS.isNotEmpty() && !Tag->isCompleteDefinition() &&
3785 !IsExplicitInstantiation && !IsExplicitSpecialization &&
3786 !isa<ClassTemplatePartialSpecializationDecl>(Tag)) {
3787 // Per C++ [dcl.type.elab]p1, a class declaration cannot have a
3788 // nested-name-specifier unless it is an explicit instantiation
3789 // or an explicit specialization.
3791 // FIXME: We allow class template partial specializations here too, per the
3792 // obvious intent of DR1819.
3794 // Per C++ [dcl.enum]p1, an opaque-enum-declaration can't either.
3795 Diag(SS.getBeginLoc(), diag::err_standalone_class_nested_name_specifier)
3796 << GetDiagnosticTypeSpecifierID(DS.getTypeSpecType()) << SS.getRange();
3800 // Track whether this decl-specifier declares anything.
3801 bool DeclaresAnything = true;
3803 // Handle anonymous struct definitions.
3804 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) {
3805 if (!Record->getDeclName() && Record->isCompleteDefinition() &&
3806 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) {
3807 if (getLangOpts().CPlusPlus ||
3808 Record->getDeclContext()->isRecord()) {
3809 // If CurContext is a DeclContext that can contain statements,
3810 // RecursiveASTVisitor won't visit the decls that
3811 // BuildAnonymousStructOrUnion() will put into CurContext.
3812 // Also store them here so that they can be part of the
3813 // DeclStmt that gets created in this case.
3814 // FIXME: Also return the IndirectFieldDecls created by
3815 // BuildAnonymousStructOr union, for the same reason?
3816 if (CurContext->isFunctionOrMethod())
3817 AnonRecord = Record;
3818 return BuildAnonymousStructOrUnion(S, DS, AS, Record,
3819 Context.getPrintingPolicy());
3822 DeclaresAnything = false;
3827 // A struct-declaration that does not declare an anonymous structure or
3828 // anonymous union shall contain a struct-declarator-list.
3830 // This rule also existed in C89 and C99; the grammar for struct-declaration
3831 // did not permit a struct-declaration without a struct-declarator-list.
3832 if (!getLangOpts().CPlusPlus && CurContext->isRecord() &&
3833 DS.getStorageClassSpec() == DeclSpec::SCS_unspecified) {
3834 // Check for Microsoft C extension: anonymous struct/union member.
3835 // Handle 2 kinds of anonymous struct/union:
3839 // STRUCT_TYPE; <- where STRUCT_TYPE is a typedef struct.
3840 // UNION_TYPE; <- where UNION_TYPE is a typedef union.
3841 if ((Tag && Tag->getDeclName()) ||
3842 DS.getTypeSpecType() == DeclSpec::TST_typename) {
3843 RecordDecl *Record = nullptr;
3845 Record = dyn_cast<RecordDecl>(Tag);
3846 else if (const RecordType *RT =
3847 DS.getRepAsType().get()->getAsStructureType())
3848 Record = RT->getDecl();
3849 else if (const RecordType *UT = DS.getRepAsType().get()->getAsUnionType())
3850 Record = UT->getDecl();
3852 if (Record && getLangOpts().MicrosoftExt) {
3853 Diag(DS.getLocStart(), diag::ext_ms_anonymous_record)
3854 << Record->isUnion() << DS.getSourceRange();
3855 return BuildMicrosoftCAnonymousStruct(S, DS, Record);
3858 DeclaresAnything = false;
3862 // Skip all the checks below if we have a type error.
3863 if (DS.getTypeSpecType() == DeclSpec::TST_error ||
3864 (TagD && TagD->isInvalidDecl()))
3867 if (getLangOpts().CPlusPlus &&
3868 DS.getStorageClassSpec() != DeclSpec::SCS_typedef)
3869 if (EnumDecl *Enum = dyn_cast_or_null<EnumDecl>(Tag))
3870 if (Enum->enumerator_begin() == Enum->enumerator_end() &&
3871 !Enum->getIdentifier() && !Enum->isInvalidDecl())
3872 DeclaresAnything = false;
3874 if (!DS.isMissingDeclaratorOk()) {
3875 // Customize diagnostic for a typedef missing a name.
3876 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef)
3877 Diag(DS.getLocStart(), diag::ext_typedef_without_a_name)
3878 << DS.getSourceRange();
3880 DeclaresAnything = false;
3883 if (DS.isModulePrivateSpecified() &&
3884 Tag && Tag->getDeclContext()->isFunctionOrMethod())
3885 Diag(DS.getModulePrivateSpecLoc(), diag::err_module_private_local_class)
3886 << Tag->getTagKind()
3887 << FixItHint::CreateRemoval(DS.getModulePrivateSpecLoc());
3889 ActOnDocumentableDecl(TagD);
3892 // A declaration [...] shall declare at least a declarator [...], a tag,
3893 // or the members of an enumeration.
3895 // [If there are no declarators], and except for the declaration of an
3896 // unnamed bit-field, the decl-specifier-seq shall introduce one or more
3897 // names into the program, or shall redeclare a name introduced by a
3898 // previous declaration.
3899 if (!DeclaresAnything) {
3900 // In C, we allow this as a (popular) extension / bug. Don't bother
3901 // producing further diagnostics for redundant qualifiers after this.
3902 Diag(DS.getLocStart(), diag::ext_no_declarators) << DS.getSourceRange();
3907 // If a storage-class-specifier appears in a decl-specifier-seq, [...] the
3908 // init-declarator-list of the declaration shall not be empty.
3909 // C++ [dcl.fct.spec]p1:
3910 // If a cv-qualifier appears in a decl-specifier-seq, the
3911 // init-declarator-list of the declaration shall not be empty.
3913 // Spurious qualifiers here appear to be valid in C.
3914 unsigned DiagID = diag::warn_standalone_specifier;
3915 if (getLangOpts().CPlusPlus)
3916 DiagID = diag::ext_standalone_specifier;
3918 // Note that a linkage-specification sets a storage class, but
3919 // 'extern "C" struct foo;' is actually valid and not theoretically
3921 if (DeclSpec::SCS SCS = DS.getStorageClassSpec()) {
3922 if (SCS == DeclSpec::SCS_mutable)
3923 // Since mutable is not a viable storage class specifier in C, there is
3924 // no reason to treat it as an extension. Instead, diagnose as an error.
3925 Diag(DS.getStorageClassSpecLoc(), diag::err_mutable_nonmember);
3926 else if (!DS.isExternInLinkageSpec() && SCS != DeclSpec::SCS_typedef)
3927 Diag(DS.getStorageClassSpecLoc(), DiagID)
3928 << DeclSpec::getSpecifierName(SCS);
3931 if (DeclSpec::TSCS TSCS = DS.getThreadStorageClassSpec())
3932 Diag(DS.getThreadStorageClassSpecLoc(), DiagID)
3933 << DeclSpec::getSpecifierName(TSCS);
3934 if (DS.getTypeQualifiers()) {
3935 if (DS.getTypeQualifiers() & DeclSpec::TQ_const)
3936 Diag(DS.getConstSpecLoc(), DiagID) << "const";
3937 if (DS.getTypeQualifiers() & DeclSpec::TQ_volatile)
3938 Diag(DS.getConstSpecLoc(), DiagID) << "volatile";
3939 // Restrict is covered above.
3940 if (DS.getTypeQualifiers() & DeclSpec::TQ_atomic)
3941 Diag(DS.getAtomicSpecLoc(), DiagID) << "_Atomic";
3944 // Warn about ignored type attributes, for example:
3945 // __attribute__((aligned)) struct A;
3946 // Attributes should be placed after tag to apply to type declaration.
3947 if (!DS.getAttributes().empty()) {
3948 DeclSpec::TST TypeSpecType = DS.getTypeSpecType();
3949 if (TypeSpecType == DeclSpec::TST_class ||
3950 TypeSpecType == DeclSpec::TST_struct ||
3951 TypeSpecType == DeclSpec::TST_interface ||
3952 TypeSpecType == DeclSpec::TST_union ||
3953 TypeSpecType == DeclSpec::TST_enum) {
3954 for (AttributeList* attrs = DS.getAttributes().getList(); attrs;
3955 attrs = attrs->getNext())
3956 Diag(attrs->getLoc(), diag::warn_declspec_attribute_ignored)
3957 << attrs->getName() << GetDiagnosticTypeSpecifierID(TypeSpecType);
3964 /// We are trying to inject an anonymous member into the given scope;
3965 /// check if there's an existing declaration that can't be overloaded.
3967 /// \return true if this is a forbidden redeclaration
3968 static bool CheckAnonMemberRedeclaration(Sema &SemaRef,
3971 DeclarationName Name,
3972 SourceLocation NameLoc,
3974 LookupResult R(SemaRef, Name, NameLoc, Sema::LookupMemberName,
3975 Sema::ForRedeclaration);
3976 if (!SemaRef.LookupName(R, S)) return false;
3978 // Pick a representative declaration.
3979 NamedDecl *PrevDecl = R.getRepresentativeDecl()->getUnderlyingDecl();
3980 assert(PrevDecl && "Expected a non-null Decl");
3982 if (!SemaRef.isDeclInScope(PrevDecl, Owner, S))
3985 SemaRef.Diag(NameLoc, diag::err_anonymous_record_member_redecl)
3987 SemaRef.Diag(PrevDecl->getLocation(), diag::note_previous_declaration);
3992 /// InjectAnonymousStructOrUnionMembers - Inject the members of the
3993 /// anonymous struct or union AnonRecord into the owning context Owner
3994 /// and scope S. This routine will be invoked just after we realize
3995 /// that an unnamed union or struct is actually an anonymous union or
4002 /// }; // InjectAnonymousStructOrUnionMembers called here to inject i and
4003 /// // f into the surrounding scope.x
4006 /// This routine is recursive, injecting the names of nested anonymous
4007 /// structs/unions into the owning context and scope as well.
4009 InjectAnonymousStructOrUnionMembers(Sema &SemaRef, Scope *S, DeclContext *Owner,
4010 RecordDecl *AnonRecord, AccessSpecifier AS,
4011 SmallVectorImpl<NamedDecl *> &Chaining) {
4012 bool Invalid = false;
4014 // Look every FieldDecl and IndirectFieldDecl with a name.
4015 for (auto *D : AnonRecord->decls()) {
4016 if ((isa<FieldDecl>(D) || isa<IndirectFieldDecl>(D)) &&
4017 cast<NamedDecl>(D)->getDeclName()) {
4018 ValueDecl *VD = cast<ValueDecl>(D);
4019 if (CheckAnonMemberRedeclaration(SemaRef, S, Owner, VD->getDeclName(),
4021 AnonRecord->isUnion())) {
4022 // C++ [class.union]p2:
4023 // The names of the members of an anonymous union shall be
4024 // distinct from the names of any other entity in the
4025 // scope in which the anonymous union is declared.
4028 // C++ [class.union]p2:
4029 // For the purpose of name lookup, after the anonymous union
4030 // definition, the members of the anonymous union are
4031 // considered to have been defined in the scope in which the
4032 // anonymous union is declared.
4033 unsigned OldChainingSize = Chaining.size();
4034 if (IndirectFieldDecl *IF = dyn_cast<IndirectFieldDecl>(VD))
4035 Chaining.append(IF->chain_begin(), IF->chain_end());
4037 Chaining.push_back(VD);
4039 assert(Chaining.size() >= 2);
4040 NamedDecl **NamedChain =
4041 new (SemaRef.Context)NamedDecl*[Chaining.size()];
4042 for (unsigned i = 0; i < Chaining.size(); i++)
4043 NamedChain[i] = Chaining[i];
4045 IndirectFieldDecl *IndirectField = IndirectFieldDecl::Create(
4046 SemaRef.Context, Owner, VD->getLocation(), VD->getIdentifier(),
4047 VD->getType(), NamedChain, Chaining.size());
4049 for (const auto *Attr : VD->attrs())
4050 IndirectField->addAttr(Attr->clone(SemaRef.Context));
4052 IndirectField->setAccess(AS);
4053 IndirectField->setImplicit();
4054 SemaRef.PushOnScopeChains(IndirectField, S);
4056 // That includes picking up the appropriate access specifier.
4057 if (AS != AS_none) IndirectField->setAccess(AS);
4059 Chaining.resize(OldChainingSize);
4067 /// StorageClassSpecToVarDeclStorageClass - Maps a DeclSpec::SCS to
4068 /// a VarDecl::StorageClass. Any error reporting is up to the caller:
4069 /// illegal input values are mapped to SC_None.
4071 StorageClassSpecToVarDeclStorageClass(const DeclSpec &DS) {
4072 DeclSpec::SCS StorageClassSpec = DS.getStorageClassSpec();
4073 assert(StorageClassSpec != DeclSpec::SCS_typedef &&
4074 "Parser allowed 'typedef' as storage class VarDecl.");
4075 switch (StorageClassSpec) {
4076 case DeclSpec::SCS_unspecified: return SC_None;
4077 case DeclSpec::SCS_extern:
4078 if (DS.isExternInLinkageSpec())
4081 case DeclSpec::SCS_static: return SC_Static;
4082 case DeclSpec::SCS_auto: return SC_Auto;
4083 case DeclSpec::SCS_register: return SC_Register;
4084 case DeclSpec::SCS_private_extern: return SC_PrivateExtern;
4085 // Illegal SCSs map to None: error reporting is up to the caller.
4086 case DeclSpec::SCS_mutable: // Fall through.
4087 case DeclSpec::SCS_typedef: return SC_None;
4089 llvm_unreachable("unknown storage class specifier");
4092 static SourceLocation findDefaultInitializer(const CXXRecordDecl *Record) {
4093 assert(Record->hasInClassInitializer());
4095 for (const auto *I : Record->decls()) {
4096 const auto *FD = dyn_cast<FieldDecl>(I);
4097 if (const auto *IFD = dyn_cast<IndirectFieldDecl>(I))
4098 FD = IFD->getAnonField();
4099 if (FD && FD->hasInClassInitializer())
4100 return FD->getLocation();
4103 llvm_unreachable("couldn't find in-class initializer");
4106 static void checkDuplicateDefaultInit(Sema &S, CXXRecordDecl *Parent,
4107 SourceLocation DefaultInitLoc) {
4108 if (!Parent->isUnion() || !Parent->hasInClassInitializer())
4111 S.Diag(DefaultInitLoc, diag::err_multiple_mem_union_initialization);
4112 S.Diag(findDefaultInitializer(Parent), diag::note_previous_initializer) << 0;
4115 static void checkDuplicateDefaultInit(Sema &S, CXXRecordDecl *Parent,
4116 CXXRecordDecl *AnonUnion) {
4117 if (!Parent->isUnion() || !Parent->hasInClassInitializer())
4120 checkDuplicateDefaultInit(S, Parent, findDefaultInitializer(AnonUnion));
4123 /// BuildAnonymousStructOrUnion - Handle the declaration of an
4124 /// anonymous structure or union. Anonymous unions are a C++ feature
4125 /// (C++ [class.union]) and a C11 feature; anonymous structures
4126 /// are a C11 feature and GNU C++ extension.
4127 Decl *Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS,
4130 const PrintingPolicy &Policy) {
4131 DeclContext *Owner = Record->getDeclContext();
4133 // Diagnose whether this anonymous struct/union is an extension.
4134 if (Record->isUnion() && !getLangOpts().CPlusPlus && !getLangOpts().C11)
4135 Diag(Record->getLocation(), diag::ext_anonymous_union);
4136 else if (!Record->isUnion() && getLangOpts().CPlusPlus)
4137 Diag(Record->getLocation(), diag::ext_gnu_anonymous_struct);
4138 else if (!Record->isUnion() && !getLangOpts().C11)
4139 Diag(Record->getLocation(), diag::ext_c11_anonymous_struct);
4141 // C and C++ require different kinds of checks for anonymous
4143 bool Invalid = false;
4144 if (getLangOpts().CPlusPlus) {
4145 const char *PrevSpec = nullptr;
4147 if (Record->isUnion()) {
4148 // C++ [class.union]p6:
4149 // Anonymous unions declared in a named namespace or in the
4150 // global namespace shall be declared static.
4151 if (DS.getStorageClassSpec() != DeclSpec::SCS_static &&
4152 (isa<TranslationUnitDecl>(Owner) ||
4153 (isa<NamespaceDecl>(Owner) &&
4154 cast<NamespaceDecl>(Owner)->getDeclName()))) {
4155 Diag(Record->getLocation(), diag::err_anonymous_union_not_static)
4156 << FixItHint::CreateInsertion(Record->getLocation(), "static ");
4158 // Recover by adding 'static'.
4159 DS.SetStorageClassSpec(*this, DeclSpec::SCS_static, SourceLocation(),
4160 PrevSpec, DiagID, Policy);
4162 // C++ [class.union]p6:
4163 // A storage class is not allowed in a declaration of an
4164 // anonymous union in a class scope.
4165 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified &&
4166 isa<RecordDecl>(Owner)) {
4167 Diag(DS.getStorageClassSpecLoc(),
4168 diag::err_anonymous_union_with_storage_spec)
4169 << FixItHint::CreateRemoval(DS.getStorageClassSpecLoc());
4171 // Recover by removing the storage specifier.
4172 DS.SetStorageClassSpec(*this, DeclSpec::SCS_unspecified,
4174 PrevSpec, DiagID, Context.getPrintingPolicy());
4178 // Ignore const/volatile/restrict qualifiers.
4179 if (DS.getTypeQualifiers()) {
4180 if (DS.getTypeQualifiers() & DeclSpec::TQ_const)
4181 Diag(DS.getConstSpecLoc(), diag::ext_anonymous_struct_union_qualified)
4182 << Record->isUnion() << "const"
4183 << FixItHint::CreateRemoval(DS.getConstSpecLoc());
4184 if (DS.getTypeQualifiers() & DeclSpec::TQ_volatile)
4185 Diag(DS.getVolatileSpecLoc(),
4186 diag::ext_anonymous_struct_union_qualified)
4187 << Record->isUnion() << "volatile"
4188 << FixItHint::CreateRemoval(DS.getVolatileSpecLoc());
4189 if (DS.getTypeQualifiers() & DeclSpec::TQ_restrict)
4190 Diag(DS.getRestrictSpecLoc(),
4191 diag::ext_anonymous_struct_union_qualified)
4192 << Record->isUnion() << "restrict"
4193 << FixItHint::CreateRemoval(DS.getRestrictSpecLoc());
4194 if (DS.getTypeQualifiers() & DeclSpec::TQ_atomic)
4195 Diag(DS.getAtomicSpecLoc(),
4196 diag::ext_anonymous_struct_union_qualified)
4197 << Record->isUnion() << "_Atomic"
4198 << FixItHint::CreateRemoval(DS.getAtomicSpecLoc());
4200 DS.ClearTypeQualifiers();
4203 // C++ [class.union]p2:
4204 // The member-specification of an anonymous union shall only
4205 // define non-static data members. [Note: nested types and
4206 // functions cannot be declared within an anonymous union. ]
4207 for (auto *Mem : Record->decls()) {
4208 if (auto *FD = dyn_cast<FieldDecl>(Mem)) {
4209 // C++ [class.union]p3:
4210 // An anonymous union shall not have private or protected
4211 // members (clause 11).
4212 assert(FD->getAccess() != AS_none);
4213 if (FD->getAccess() != AS_public) {
4214 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member)
4215 << Record->isUnion() << (FD->getAccess() == AS_protected);
4219 // C++ [class.union]p1
4220 // An object of a class with a non-trivial constructor, a non-trivial
4221 // copy constructor, a non-trivial destructor, or a non-trivial copy
4222 // assignment operator cannot be a member of a union, nor can an
4223 // array of such objects.
4224 if (CheckNontrivialField(FD))
4226 } else if (Mem->isImplicit()) {
4227 // Any implicit members are fine.
4228 } else if (isa<TagDecl>(Mem) && Mem->getDeclContext() != Record) {
4229 // This is a type that showed up in an
4230 // elaborated-type-specifier inside the anonymous struct or
4231 // union, but which actually declares a type outside of the
4232 // anonymous struct or union. It's okay.
4233 } else if (auto *MemRecord = dyn_cast<RecordDecl>(Mem)) {
4234 if (!MemRecord->isAnonymousStructOrUnion() &&
4235 MemRecord->getDeclName()) {
4236 // Visual C++ allows type definition in anonymous struct or union.
4237 if (getLangOpts().MicrosoftExt)
4238 Diag(MemRecord->getLocation(), diag::ext_anonymous_record_with_type)
4239 << Record->isUnion();
4241 // This is a nested type declaration.
4242 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type)
4243 << Record->isUnion();
4247 // This is an anonymous type definition within another anonymous type.
4248 // This is a popular extension, provided by Plan9, MSVC and GCC, but
4249 // not part of standard C++.
4250 Diag(MemRecord->getLocation(),
4251 diag::ext_anonymous_record_with_anonymous_type)
4252 << Record->isUnion();
4254 } else if (isa<AccessSpecDecl>(Mem)) {
4255 // Any access specifier is fine.
4256 } else if (isa<StaticAssertDecl>(Mem)) {
4257 // In C++1z, static_assert declarations are also fine.
4259 // We have something that isn't a non-static data
4260 // member. Complain about it.
4261 unsigned DK = diag::err_anonymous_record_bad_member;
4262 if (isa<TypeDecl>(Mem))
4263 DK = diag::err_anonymous_record_with_type;
4264 else if (isa<FunctionDecl>(Mem))
4265 DK = diag::err_anonymous_record_with_function;
4266 else if (isa<VarDecl>(Mem))
4267 DK = diag::err_anonymous_record_with_static;
4269 // Visual C++ allows type definition in anonymous struct or union.
4270 if (getLangOpts().MicrosoftExt &&
4271 DK == diag::err_anonymous_record_with_type)
4272 Diag(Mem->getLocation(), diag::ext_anonymous_record_with_type)
4273 << Record->isUnion();
4275 Diag(Mem->getLocation(), DK) << Record->isUnion();
4281 // C++11 [class.union]p8 (DR1460):
4282 // At most one variant member of a union may have a
4283 // brace-or-equal-initializer.
4284 if (cast<CXXRecordDecl>(Record)->hasInClassInitializer() &&
4286 checkDuplicateDefaultInit(*this, cast<CXXRecordDecl>(Owner),
4287 cast<CXXRecordDecl>(Record));
4290 if (!Record->isUnion() && !Owner->isRecord()) {
4291 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member)
4292 << getLangOpts().CPlusPlus;
4296 // Mock up a declarator.
4297 Declarator Dc(DS, Declarator::MemberContext);
4298 TypeSourceInfo *TInfo = GetTypeForDeclarator(Dc, S);
4299 assert(TInfo && "couldn't build declarator info for anonymous struct/union");
4301 // Create a declaration for this anonymous struct/union.
4302 NamedDecl *Anon = nullptr;
4303 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) {
4304 Anon = FieldDecl::Create(Context, OwningClass,
4306 Record->getLocation(),
4307 /*IdentifierInfo=*/nullptr,
4308 Context.getTypeDeclType(Record),
4310 /*BitWidth=*/nullptr, /*Mutable=*/false,
4311 /*InitStyle=*/ICIS_NoInit);
4312 Anon->setAccess(AS);
4313 if (getLangOpts().CPlusPlus)
4314 FieldCollector->Add(cast<FieldDecl>(Anon));
4316 DeclSpec::SCS SCSpec = DS.getStorageClassSpec();
4317 StorageClass SC = StorageClassSpecToVarDeclStorageClass(DS);
4318 if (SCSpec == DeclSpec::SCS_mutable) {
4319 // mutable can only appear on non-static class members, so it's always
4321 Diag(Record->getLocation(), diag::err_mutable_nonmember);
4326 Anon = VarDecl::Create(Context, Owner,
4328 Record->getLocation(), /*IdentifierInfo=*/nullptr,
4329 Context.getTypeDeclType(Record),
4332 // Default-initialize the implicit variable. This initialization will be
4333 // trivial in almost all cases, except if a union member has an in-class
4335 // union { int n = 0; };
4336 ActOnUninitializedDecl(Anon, /*TypeMayContainAuto=*/false);
4338 Anon->setImplicit();
4340 // Mark this as an anonymous struct/union type.
4341 Record->setAnonymousStructOrUnion(true);
4343 // Add the anonymous struct/union object to the current
4344 // context. We'll be referencing this object when we refer to one of
4346 Owner->addDecl(Anon);
4348 // Inject the members of the anonymous struct/union into the owning
4349 // context and into the identifier resolver chain for name lookup
4351 SmallVector<NamedDecl*, 2> Chain;
4352 Chain.push_back(Anon);
4354 if (InjectAnonymousStructOrUnionMembers(*this, S, Owner, Record, AS, Chain))
4357 if (VarDecl *NewVD = dyn_cast<VarDecl>(Anon)) {
4358 if (getLangOpts().CPlusPlus && NewVD->isStaticLocal()) {
4359 Decl *ManglingContextDecl;
4360 if (MangleNumberingContext *MCtx = getCurrentMangleNumberContext(
4361 NewVD->getDeclContext(), ManglingContextDecl)) {
4362 Context.setManglingNumber(
4363 NewVD, MCtx->getManglingNumber(
4364 NewVD, getMSManglingNumber(getLangOpts(), S)));
4365 Context.setStaticLocalNumber(NewVD, MCtx->getStaticLocalNumber(NewVD));
4371 Anon->setInvalidDecl();
4376 /// BuildMicrosoftCAnonymousStruct - Handle the declaration of an
4377 /// Microsoft C anonymous structure.
4378 /// Ref: http://msdn.microsoft.com/en-us/library/z2cx9y4f.aspx
4381 /// struct A { int a; };
4382 /// struct B { struct A; int b; };
4389 Decl *Sema::BuildMicrosoftCAnonymousStruct(Scope *S, DeclSpec &DS,
4390 RecordDecl *Record) {
4391 assert(Record && "expected a record!");
4393 // Mock up a declarator.
4394 Declarator Dc(DS, Declarator::TypeNameContext);
4395 TypeSourceInfo *TInfo = GetTypeForDeclarator(Dc, S);
4396 assert(TInfo && "couldn't build declarator info for anonymous struct");
4398 auto *ParentDecl = cast<RecordDecl>(CurContext);
4399 QualType RecTy = Context.getTypeDeclType(Record);
4401 // Create a declaration for this anonymous struct.
4402 NamedDecl *Anon = FieldDecl::Create(Context,
4406 /*IdentifierInfo=*/nullptr,
4409 /*BitWidth=*/nullptr, /*Mutable=*/false,
4410 /*InitStyle=*/ICIS_NoInit);
4411 Anon->setImplicit();
4413 // Add the anonymous struct object to the current context.
4414 CurContext->addDecl(Anon);
4416 // Inject the members of the anonymous struct into the current
4417 // context and into the identifier resolver chain for name lookup
4419 SmallVector<NamedDecl*, 2> Chain;
4420 Chain.push_back(Anon);
4422 RecordDecl *RecordDef = Record->getDefinition();
4423 if (RequireCompleteType(Anon->getLocation(), RecTy,
4424 diag::err_field_incomplete) ||
4425 InjectAnonymousStructOrUnionMembers(*this, S, CurContext, RecordDef,
4427 Anon->setInvalidDecl();
4428 ParentDecl->setInvalidDecl();
4434 /// GetNameForDeclarator - Determine the full declaration name for the
4435 /// given Declarator.
4436 DeclarationNameInfo Sema::GetNameForDeclarator(Declarator &D) {
4437 return GetNameFromUnqualifiedId(D.getName());
4440 /// \brief Retrieves the declaration name from a parsed unqualified-id.
4442 Sema::GetNameFromUnqualifiedId(const UnqualifiedId &Name) {
4443 DeclarationNameInfo NameInfo;
4444 NameInfo.setLoc(Name.StartLocation);
4446 switch (Name.getKind()) {
4448 case UnqualifiedId::IK_ImplicitSelfParam:
4449 case UnqualifiedId::IK_Identifier:
4450 NameInfo.setName(Name.Identifier);
4451 NameInfo.setLoc(Name.StartLocation);
4454 case UnqualifiedId::IK_OperatorFunctionId:
4455 NameInfo.setName(Context.DeclarationNames.getCXXOperatorName(
4456 Name.OperatorFunctionId.Operator));
4457 NameInfo.setLoc(Name.StartLocation);
4458 NameInfo.getInfo().CXXOperatorName.BeginOpNameLoc
4459 = Name.OperatorFunctionId.SymbolLocations[0];
4460 NameInfo.getInfo().CXXOperatorName.EndOpNameLoc
4461 = Name.EndLocation.getRawEncoding();
4464 case UnqualifiedId::IK_LiteralOperatorId:
4465 NameInfo.setName(Context.DeclarationNames.getCXXLiteralOperatorName(
4467 NameInfo.setLoc(Name.StartLocation);
4468 NameInfo.setCXXLiteralOperatorNameLoc(Name.EndLocation);
4471 case UnqualifiedId::IK_ConversionFunctionId: {
4472 TypeSourceInfo *TInfo;
4473 QualType Ty = GetTypeFromParser(Name.ConversionFunctionId, &TInfo);
4475 return DeclarationNameInfo();
4476 NameInfo.setName(Context.DeclarationNames.getCXXConversionFunctionName(
4477 Context.getCanonicalType(Ty)));
4478 NameInfo.setLoc(Name.StartLocation);
4479 NameInfo.setNamedTypeInfo(TInfo);
4483 case UnqualifiedId::IK_ConstructorName: {
4484 TypeSourceInfo *TInfo;
4485 QualType Ty = GetTypeFromParser(Name.ConstructorName, &TInfo);
4487 return DeclarationNameInfo();
4488 NameInfo.setName(Context.DeclarationNames.getCXXConstructorName(
4489 Context.getCanonicalType(Ty)));
4490 NameInfo.setLoc(Name.StartLocation);
4491 NameInfo.setNamedTypeInfo(TInfo);
4495 case UnqualifiedId::IK_ConstructorTemplateId: {
4496 // In well-formed code, we can only have a constructor
4497 // template-id that refers to the current context, so go there
4498 // to find the actual type being constructed.
4499 CXXRecordDecl *CurClass = dyn_cast<CXXRecordDecl>(CurContext);
4500 if (!CurClass || CurClass->getIdentifier() != Name.TemplateId->Name)
4501 return DeclarationNameInfo();
4503 // Determine the type of the class being constructed.
4504 QualType CurClassType = Context.getTypeDeclType(CurClass);
4506 // FIXME: Check two things: that the template-id names the same type as
4507 // CurClassType, and that the template-id does not occur when the name
4510 NameInfo.setName(Context.DeclarationNames.getCXXConstructorName(
4511 Context.getCanonicalType(CurClassType)));
4512 NameInfo.setLoc(Name.StartLocation);
4513 // FIXME: should we retrieve TypeSourceInfo?
4514 NameInfo.setNamedTypeInfo(nullptr);
4518 case UnqualifiedId::IK_DestructorName: {
4519 TypeSourceInfo *TInfo;
4520 QualType Ty = GetTypeFromParser(Name.DestructorName, &TInfo);
4522 return DeclarationNameInfo();
4523 NameInfo.setName(Context.DeclarationNames.getCXXDestructorName(
4524 Context.getCanonicalType(Ty)));
4525 NameInfo.setLoc(Name.StartLocation);
4526 NameInfo.setNamedTypeInfo(TInfo);
4530 case UnqualifiedId::IK_TemplateId: {
4531 TemplateName TName = Name.TemplateId->Template.get();
4532 SourceLocation TNameLoc = Name.TemplateId->TemplateNameLoc;
4533 return Context.getNameForTemplate(TName, TNameLoc);
4536 } // switch (Name.getKind())
4538 llvm_unreachable("Unknown name kind");
4541 static QualType getCoreType(QualType Ty) {
4543 if (Ty->isPointerType() || Ty->isReferenceType())
4544 Ty = Ty->getPointeeType();
4545 else if (Ty->isArrayType())
4546 Ty = Ty->castAsArrayTypeUnsafe()->getElementType();
4548 return Ty.withoutLocalFastQualifiers();
4552 /// hasSimilarParameters - Determine whether the C++ functions Declaration
4553 /// and Definition have "nearly" matching parameters. This heuristic is
4554 /// used to improve diagnostics in the case where an out-of-line function
4555 /// definition doesn't match any declaration within the class or namespace.
4556 /// Also sets Params to the list of indices to the parameters that differ
4557 /// between the declaration and the definition. If hasSimilarParameters
4558 /// returns true and Params is empty, then all of the parameters match.
4559 static bool hasSimilarParameters(ASTContext &Context,
4560 FunctionDecl *Declaration,
4561 FunctionDecl *Definition,
4562 SmallVectorImpl<unsigned> &Params) {
4564 if (Declaration->param_size() != Definition->param_size())
4566 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) {
4567 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType();
4568 QualType DefParamTy = Definition->getParamDecl(Idx)->getType();
4570 // The parameter types are identical
4571 if (Context.hasSameType(DefParamTy, DeclParamTy))
4574 QualType DeclParamBaseTy = getCoreType(DeclParamTy);
4575 QualType DefParamBaseTy = getCoreType(DefParamTy);
4576 const IdentifierInfo *DeclTyName = DeclParamBaseTy.getBaseTypeIdentifier();
4577 const IdentifierInfo *DefTyName = DefParamBaseTy.getBaseTypeIdentifier();
4579 if (Context.hasSameUnqualifiedType(DeclParamBaseTy, DefParamBaseTy) ||
4580 (DeclTyName && DeclTyName == DefTyName))
4581 Params.push_back(Idx);
4582 else // The two parameters aren't even close
4589 /// NeedsRebuildingInCurrentInstantiation - Checks whether the given
4590 /// declarator needs to be rebuilt in the current instantiation.
4591 /// Any bits of declarator which appear before the name are valid for
4592 /// consideration here. That's specifically the type in the decl spec
4593 /// and the base type in any member-pointer chunks.
4594 static bool RebuildDeclaratorInCurrentInstantiation(Sema &S, Declarator &D,
4595 DeclarationName Name) {
4596 // The types we specifically need to rebuild are:
4597 // - typenames, typeofs, and decltypes
4598 // - types which will become injected class names
4599 // Of course, we also need to rebuild any type referencing such a
4600 // type. It's safest to just say "dependent", but we call out a
4603 DeclSpec &DS = D.getMutableDeclSpec();
4604 switch (DS.getTypeSpecType()) {
4605 case DeclSpec::TST_typename:
4606 case DeclSpec::TST_typeofType:
4607 case DeclSpec::TST_underlyingType:
4608 case DeclSpec::TST_atomic: {
4609 // Grab the type from the parser.
4610 TypeSourceInfo *TSI = nullptr;
4611 QualType T = S.GetTypeFromParser(DS.getRepAsType(), &TSI);
4612 if (T.isNull() || !T->isDependentType()) break;
4614 // Make sure there's a type source info. This isn't really much
4615 // of a waste; most dependent types should have type source info
4616 // attached already.
4618 TSI = S.Context.getTrivialTypeSourceInfo(T, DS.getTypeSpecTypeLoc());
4620 // Rebuild the type in the current instantiation.
4621 TSI = S.RebuildTypeInCurrentInstantiation(TSI, D.getIdentifierLoc(), Name);
4622 if (!TSI) return true;
4624 // Store the new type back in the decl spec.
4625 ParsedType LocType = S.CreateParsedType(TSI->getType(), TSI);
4626 DS.UpdateTypeRep(LocType);
4630 case DeclSpec::TST_decltype:
4631 case DeclSpec::TST_typeofExpr: {
4632 Expr *E = DS.getRepAsExpr();
4633 ExprResult Result = S.RebuildExprInCurrentInstantiation(E);
4634 if (Result.isInvalid()) return true;
4635 DS.UpdateExprRep(Result.get());
4640 // Nothing to do for these decl specs.
4644 // It doesn't matter what order we do this in.
4645 for (unsigned I = 0, E = D.getNumTypeObjects(); I != E; ++I) {
4646 DeclaratorChunk &Chunk = D.getTypeObject(I);
4648 // The only type information in the declarator which can come
4649 // before the declaration name is the base type of a member
4651 if (Chunk.Kind != DeclaratorChunk::MemberPointer)
4654 // Rebuild the scope specifier in-place.
4655 CXXScopeSpec &SS = Chunk.Mem.Scope();
4656 if (S.RebuildNestedNameSpecifierInCurrentInstantiation(SS))
4663 Decl *Sema::ActOnDeclarator(Scope *S, Declarator &D) {
4664 D.setFunctionDefinitionKind(FDK_Declaration);
4665 Decl *Dcl = HandleDeclarator(S, D, MultiTemplateParamsArg());
4667 if (OriginalLexicalContext && OriginalLexicalContext->isObjCContainer() &&
4668 Dcl && Dcl->getDeclContext()->isFileContext())
4669 Dcl->setTopLevelDeclInObjCContainer();
4674 /// DiagnoseClassNameShadow - Implement C++ [class.mem]p13:
4675 /// If T is the name of a class, then each of the following shall have a
4676 /// name different from T:
4677 /// - every static data member of class T;
4678 /// - every member function of class T
4679 /// - every member of class T that is itself a type;
4680 /// \returns true if the declaration name violates these rules.
4681 bool Sema::DiagnoseClassNameShadow(DeclContext *DC,
4682 DeclarationNameInfo NameInfo) {
4683 DeclarationName Name = NameInfo.getName();
4685 CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(DC);
4686 while (Record && Record->isAnonymousStructOrUnion())
4687 Record = dyn_cast<CXXRecordDecl>(Record->getParent());
4688 if (Record && Record->getIdentifier() && Record->getDeclName() == Name) {
4689 Diag(NameInfo.getLoc(), diag::err_member_name_of_class) << Name;
4696 /// \brief Diagnose a declaration whose declarator-id has the given
4697 /// nested-name-specifier.
4699 /// \param SS The nested-name-specifier of the declarator-id.
4701 /// \param DC The declaration context to which the nested-name-specifier
4704 /// \param Name The name of the entity being declared.
4706 /// \param Loc The location of the name of the entity being declared.
4708 /// \returns true if we cannot safely recover from this error, false otherwise.
4709 bool Sema::diagnoseQualifiedDeclaration(CXXScopeSpec &SS, DeclContext *DC,
4710 DeclarationName Name,
4711 SourceLocation Loc) {
4712 DeclContext *Cur = CurContext;
4713 while (isa<LinkageSpecDecl>(Cur) || isa<CapturedDecl>(Cur))
4714 Cur = Cur->getParent();
4716 // If the user provided a superfluous scope specifier that refers back to the
4717 // class in which the entity is already declared, diagnose and ignore it.
4723 // Note, it was once ill-formed to give redundant qualification in all
4724 // contexts, but that rule was removed by DR482.
4725 if (Cur->Equals(DC)) {
4726 if (Cur->isRecord()) {
4727 Diag(Loc, LangOpts.MicrosoftExt ? diag::warn_member_extra_qualification
4728 : diag::err_member_extra_qualification)
4729 << Name << FixItHint::CreateRemoval(SS.getRange());
4732 Diag(Loc, diag::warn_namespace_member_extra_qualification) << Name;
4737 // Check whether the qualifying scope encloses the scope of the original
4739 if (!Cur->Encloses(DC)) {
4740 if (Cur->isRecord())
4741 Diag(Loc, diag::err_member_qualification)
4742 << Name << SS.getRange();
4743 else if (isa<TranslationUnitDecl>(DC))
4744 Diag(Loc, diag::err_invalid_declarator_global_scope)
4745 << Name << SS.getRange();
4746 else if (isa<FunctionDecl>(Cur))
4747 Diag(Loc, diag::err_invalid_declarator_in_function)
4748 << Name << SS.getRange();
4749 else if (isa<BlockDecl>(Cur))
4750 Diag(Loc, diag::err_invalid_declarator_in_block)
4751 << Name << SS.getRange();
4753 Diag(Loc, diag::err_invalid_declarator_scope)
4754 << Name << cast<NamedDecl>(Cur) << cast<NamedDecl>(DC) << SS.getRange();
4759 if (Cur->isRecord()) {
4760 // Cannot qualify members within a class.
4761 Diag(Loc, diag::err_member_qualification)
4762 << Name << SS.getRange();
4765 // C++ constructors and destructors with incorrect scopes can break
4766 // our AST invariants by having the wrong underlying types. If
4767 // that's the case, then drop this declaration entirely.
4768 if ((Name.getNameKind() == DeclarationName::CXXConstructorName ||
4769 Name.getNameKind() == DeclarationName::CXXDestructorName) &&
4770 !Context.hasSameType(Name.getCXXNameType(),
4771 Context.getTypeDeclType(cast<CXXRecordDecl>(Cur))))
4777 // C++11 [dcl.meaning]p1:
4778 // [...] "The nested-name-specifier of the qualified declarator-id shall
4779 // not begin with a decltype-specifer"
4780 NestedNameSpecifierLoc SpecLoc(SS.getScopeRep(), SS.location_data());
4781 while (SpecLoc.getPrefix())
4782 SpecLoc = SpecLoc.getPrefix();
4783 if (dyn_cast_or_null<DecltypeType>(
4784 SpecLoc.getNestedNameSpecifier()->getAsType()))
4785 Diag(Loc, diag::err_decltype_in_declarator)
4786 << SpecLoc.getTypeLoc().getSourceRange();
4791 NamedDecl *Sema::HandleDeclarator(Scope *S, Declarator &D,
4792 MultiTemplateParamsArg TemplateParamLists) {
4793 // TODO: consider using NameInfo for diagnostic.
4794 DeclarationNameInfo NameInfo = GetNameForDeclarator(D);
4795 DeclarationName Name = NameInfo.getName();
4797 // All of these full declarators require an identifier. If it doesn't have
4798 // one, the ParsedFreeStandingDeclSpec action should be used.
4800 if (!D.isInvalidType()) // Reject this if we think it is valid.
4801 Diag(D.getDeclSpec().getLocStart(),
4802 diag::err_declarator_need_ident)
4803 << D.getDeclSpec().getSourceRange() << D.getSourceRange();
4805 } else if (DiagnoseUnexpandedParameterPack(NameInfo, UPPC_DeclarationType))
4808 // The scope passed in may not be a decl scope. Zip up the scope tree until
4809 // we find one that is.
4810 while ((S->getFlags() & Scope::DeclScope) == 0 ||
4811 (S->getFlags() & Scope::TemplateParamScope) != 0)
4814 DeclContext *DC = CurContext;
4815 if (D.getCXXScopeSpec().isInvalid())
4817 else if (D.getCXXScopeSpec().isSet()) {
4818 if (DiagnoseUnexpandedParameterPack(D.getCXXScopeSpec(),
4819 UPPC_DeclarationQualifier))
4822 bool EnteringContext = !D.getDeclSpec().isFriendSpecified();
4823 DC = computeDeclContext(D.getCXXScopeSpec(), EnteringContext);
4824 if (!DC || isa<EnumDecl>(DC)) {
4825 // If we could not compute the declaration context, it's because the
4826 // declaration context is dependent but does not refer to a class,
4827 // class template, or class template partial specialization. Complain
4828 // and return early, to avoid the coming semantic disaster.
4829 Diag(D.getIdentifierLoc(),
4830 diag::err_template_qualified_declarator_no_match)
4831 << D.getCXXScopeSpec().getScopeRep()
4832 << D.getCXXScopeSpec().getRange();
4835 bool IsDependentContext = DC->isDependentContext();
4837 if (!IsDependentContext &&
4838 RequireCompleteDeclContext(D.getCXXScopeSpec(), DC))
4841 // If a class is incomplete, do not parse entities inside it.
4842 if (isa<CXXRecordDecl>(DC) && !cast<CXXRecordDecl>(DC)->hasDefinition()) {
4843 Diag(D.getIdentifierLoc(),
4844 diag::err_member_def_undefined_record)
4845 << Name << DC << D.getCXXScopeSpec().getRange();
4848 if (!D.getDeclSpec().isFriendSpecified()) {
4849 if (diagnoseQualifiedDeclaration(D.getCXXScopeSpec(), DC,
4850 Name, D.getIdentifierLoc())) {
4858 // Check whether we need to rebuild the type of the given
4859 // declaration in the current instantiation.
4860 if (EnteringContext && IsDependentContext &&
4861 TemplateParamLists.size() != 0) {
4862 ContextRAII SavedContext(*this, DC);
4863 if (RebuildDeclaratorInCurrentInstantiation(*this, D, Name))
4868 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S);
4869 QualType R = TInfo->getType();
4871 if (!R->isFunctionType() && DiagnoseClassNameShadow(DC, NameInfo))
4872 // If this is a typedef, we'll end up spewing multiple diagnostics.
4873 // Just return early; it's safer. If this is a function, let the
4874 // "constructor cannot have a return type" diagnostic handle it.
4875 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef)
4878 if (DiagnoseUnexpandedParameterPack(D.getIdentifierLoc(), TInfo,
4879 UPPC_DeclarationType))
4882 LookupResult Previous(*this, NameInfo, LookupOrdinaryName,
4885 // See if this is a redefinition of a variable in the same scope.
4886 if (!D.getCXXScopeSpec().isSet()) {
4887 bool IsLinkageLookup = false;
4888 bool CreateBuiltins = false;
4890 // If the declaration we're planning to build will be a function
4891 // or object with linkage, then look for another declaration with
4892 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6).
4894 // If the declaration we're planning to build will be declared with
4895 // external linkage in the translation unit, create any builtin with
4897 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef)
4899 else if (CurContext->isFunctionOrMethod() &&
4900 (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern ||
4901 R->isFunctionType())) {
4902 IsLinkageLookup = true;
4904 CurContext->getEnclosingNamespaceContext()->isTranslationUnit();
4905 } else if (CurContext->getRedeclContext()->isTranslationUnit() &&
4906 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static)
4907 CreateBuiltins = true;
4909 if (IsLinkageLookup)
4910 Previous.clear(LookupRedeclarationWithLinkage);
4912 LookupName(Previous, S, CreateBuiltins);
4913 } else { // Something like "int foo::x;"
4914 LookupQualifiedName(Previous, DC);
4916 // C++ [dcl.meaning]p1:
4917 // When the declarator-id is qualified, the declaration shall refer to a
4918 // previously declared member of the class or namespace to which the
4919 // qualifier refers (or, in the case of a namespace, of an element of the
4920 // inline namespace set of that namespace (7.3.1)) or to a specialization
4923 // Note that we already checked the context above, and that we do not have
4924 // enough information to make sure that Previous contains the declaration
4925 // we want to match. For example, given:
4932 // void X::f(int) { } // ill-formed
4934 // In this case, Previous will point to the overload set
4935 // containing the two f's declared in X, but neither of them
4938 // C++ [dcl.meaning]p1:
4939 // [...] the member shall not merely have been introduced by a
4940 // using-declaration in the scope of the class or namespace nominated by
4941 // the nested-name-specifier of the declarator-id.
4942 RemoveUsingDecls(Previous);
4945 if (Previous.isSingleResult() &&
4946 Previous.getFoundDecl()->isTemplateParameter()) {
4947 // Maybe we will complain about the shadowed template parameter.
4948 if (!D.isInvalidType())
4949 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(),
4950 Previous.getFoundDecl());
4952 // Just pretend that we didn't see the previous declaration.
4956 // In C++, the previous declaration we find might be a tag type
4957 // (class or enum). In this case, the new declaration will hide the
4958 // tag type. Note that this does does not apply if we're declaring a
4959 // typedef (C++ [dcl.typedef]p4).
4960 if (Previous.isSingleTagDecl() &&
4961 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef)
4964 // Check that there are no default arguments other than in the parameters
4965 // of a function declaration (C++ only).
4966 if (getLangOpts().CPlusPlus)
4967 CheckExtraCXXDefaultArguments(D);
4969 if (D.getDeclSpec().isConceptSpecified()) {
4970 // C++ Concepts TS [dcl.spec.concept]p1: The concept specifier shall be
4971 // applied only to the definition of a function template or variable
4972 // template, declared in namespace scope
4973 if (!TemplateParamLists.size()) {
4974 Diag(D.getDeclSpec().getConceptSpecLoc(),
4975 diag:: err_concept_wrong_decl_kind);
4979 if (!DC->getRedeclContext()->isFileContext()) {
4980 Diag(D.getIdentifierLoc(),
4981 diag::err_concept_decls_may_only_appear_in_namespace_scope);
4988 bool AddToScope = true;
4989 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) {
4990 if (TemplateParamLists.size()) {
4991 Diag(D.getIdentifierLoc(), diag::err_template_typedef);
4995 New = ActOnTypedefDeclarator(S, D, DC, TInfo, Previous);
4996 } else if (R->isFunctionType()) {
4997 New = ActOnFunctionDeclarator(S, D, DC, TInfo, Previous,
5001 New = ActOnVariableDeclarator(S, D, DC, TInfo, Previous, TemplateParamLists,
5008 // If this has an identifier and is not an invalid redeclaration or
5009 // function template specialization, add it to the scope stack.
5010 if (New->getDeclName() && AddToScope &&
5011 !(D.isRedeclaration() && New->isInvalidDecl())) {
5012 // Only make a locally-scoped extern declaration visible if it is the first
5013 // declaration of this entity. Qualified lookup for such an entity should
5014 // only find this declaration if there is no visible declaration of it.
5015 bool AddToContext = !D.isRedeclaration() || !New->isLocalExternDecl();
5016 PushOnScopeChains(New, S, AddToContext);
5018 CurContext->addHiddenDecl(New);
5024 /// Helper method to turn variable array types into constant array
5025 /// types in certain situations which would otherwise be errors (for
5026 /// GCC compatibility).
5027 static QualType TryToFixInvalidVariablyModifiedType(QualType T,
5028 ASTContext &Context,
5029 bool &SizeIsNegative,
5030 llvm::APSInt &Oversized) {
5031 // This method tries to turn a variable array into a constant
5032 // array even when the size isn't an ICE. This is necessary
5033 // for compatibility with code that depends on gcc's buggy
5034 // constant expression folding, like struct {char x[(int)(char*)2];}
5035 SizeIsNegative = false;
5038 if (T->isDependentType())
5041 QualifierCollector Qs;
5042 const Type *Ty = Qs.strip(T);
5044 if (const PointerType* PTy = dyn_cast<PointerType>(Ty)) {
5045 QualType Pointee = PTy->getPointeeType();
5046 QualType FixedType =
5047 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative,
5049 if (FixedType.isNull()) return FixedType;
5050 FixedType = Context.getPointerType(FixedType);
5051 return Qs.apply(Context, FixedType);
5053 if (const ParenType* PTy = dyn_cast<ParenType>(Ty)) {
5054 QualType Inner = PTy->getInnerType();
5055 QualType FixedType =
5056 TryToFixInvalidVariablyModifiedType(Inner, Context, SizeIsNegative,
5058 if (FixedType.isNull()) return FixedType;
5059 FixedType = Context.getParenType(FixedType);
5060 return Qs.apply(Context, FixedType);
5063 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T);
5066 // FIXME: We should probably handle this case
5067 if (VLATy->getElementType()->isVariablyModifiedType())
5071 if (!VLATy->getSizeExpr() ||
5072 !VLATy->getSizeExpr()->EvaluateAsInt(Res, Context))
5075 // Check whether the array size is negative.
5076 if (Res.isSigned() && Res.isNegative()) {
5077 SizeIsNegative = true;
5081 // Check whether the array is too large to be addressed.
5082 unsigned ActiveSizeBits
5083 = ConstantArrayType::getNumAddressingBits(Context, VLATy->getElementType(),
5085 if (ActiveSizeBits > ConstantArrayType::getMaxSizeBits(Context)) {
5090 return Context.getConstantArrayType(VLATy->getElementType(),
5091 Res, ArrayType::Normal, 0);
5095 FixInvalidVariablyModifiedTypeLoc(TypeLoc SrcTL, TypeLoc DstTL) {
5096 SrcTL = SrcTL.getUnqualifiedLoc();
5097 DstTL = DstTL.getUnqualifiedLoc();
5098 if (PointerTypeLoc SrcPTL = SrcTL.getAs<PointerTypeLoc>()) {
5099 PointerTypeLoc DstPTL = DstTL.castAs<PointerTypeLoc>();
5100 FixInvalidVariablyModifiedTypeLoc(SrcPTL.getPointeeLoc(),
5101 DstPTL.getPointeeLoc());
5102 DstPTL.setStarLoc(SrcPTL.getStarLoc());
5105 if (ParenTypeLoc SrcPTL = SrcTL.getAs<ParenTypeLoc>()) {
5106 ParenTypeLoc DstPTL = DstTL.castAs<ParenTypeLoc>();
5107 FixInvalidVariablyModifiedTypeLoc(SrcPTL.getInnerLoc(),
5108 DstPTL.getInnerLoc());
5109 DstPTL.setLParenLoc(SrcPTL.getLParenLoc());
5110 DstPTL.setRParenLoc(SrcPTL.getRParenLoc());
5113 ArrayTypeLoc SrcATL = SrcTL.castAs<ArrayTypeLoc>();
5114 ArrayTypeLoc DstATL = DstTL.castAs<ArrayTypeLoc>();
5115 TypeLoc SrcElemTL = SrcATL.getElementLoc();
5116 TypeLoc DstElemTL = DstATL.getElementLoc();
5117 DstElemTL.initializeFullCopy(SrcElemTL);
5118 DstATL.setLBracketLoc(SrcATL.getLBracketLoc());
5119 DstATL.setSizeExpr(SrcATL.getSizeExpr());
5120 DstATL.setRBracketLoc(SrcATL.getRBracketLoc());
5123 /// Helper method to turn variable array types into constant array
5124 /// types in certain situations which would otherwise be errors (for
5125 /// GCC compatibility).
5126 static TypeSourceInfo*
5127 TryToFixInvalidVariablyModifiedTypeSourceInfo(TypeSourceInfo *TInfo,
5128 ASTContext &Context,
5129 bool &SizeIsNegative,
5130 llvm::APSInt &Oversized) {
5132 = TryToFixInvalidVariablyModifiedType(TInfo->getType(), Context,
5133 SizeIsNegative, Oversized);
5134 if (FixedTy.isNull())
5136 TypeSourceInfo *FixedTInfo = Context.getTrivialTypeSourceInfo(FixedTy);
5137 FixInvalidVariablyModifiedTypeLoc(TInfo->getTypeLoc(),
5138 FixedTInfo->getTypeLoc());
5142 /// \brief Register the given locally-scoped extern "C" declaration so
5143 /// that it can be found later for redeclarations. We include any extern "C"
5144 /// declaration that is not visible in the translation unit here, not just
5145 /// function-scope declarations.
5147 Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, Scope *S) {
5148 if (!getLangOpts().CPlusPlus &&
5149 ND->getLexicalDeclContext()->getRedeclContext()->isTranslationUnit())
5150 // Don't need to track declarations in the TU in C.
5153 // Note that we have a locally-scoped external with this name.
5154 Context.getExternCContextDecl()->makeDeclVisibleInContext(ND);
5157 NamedDecl *Sema::findLocallyScopedExternCDecl(DeclarationName Name) {
5158 // FIXME: We can have multiple results via __attribute__((overloadable)).
5159 auto Result = Context.getExternCContextDecl()->lookup(Name);
5160 return Result.empty() ? nullptr : *Result.begin();
5163 /// \brief Diagnose function specifiers on a declaration of an identifier that
5164 /// does not identify a function.
5165 void Sema::DiagnoseFunctionSpecifiers(const DeclSpec &DS) {
5166 // FIXME: We should probably indicate the identifier in question to avoid
5167 // confusion for constructs like "inline int a(), b;"
5168 if (DS.isInlineSpecified())
5169 Diag(DS.getInlineSpecLoc(),
5170 diag::err_inline_non_function);
5172 if (DS.isVirtualSpecified())
5173 Diag(DS.getVirtualSpecLoc(),
5174 diag::err_virtual_non_function);
5176 if (DS.isExplicitSpecified())
5177 Diag(DS.getExplicitSpecLoc(),
5178 diag::err_explicit_non_function);
5180 if (DS.isNoreturnSpecified())
5181 Diag(DS.getNoreturnSpecLoc(),
5182 diag::err_noreturn_non_function);
5186 Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC,
5187 TypeSourceInfo *TInfo, LookupResult &Previous) {
5188 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1).
5189 if (D.getCXXScopeSpec().isSet()) {
5190 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator)
5191 << D.getCXXScopeSpec().getRange();
5193 // Pretend we didn't see the scope specifier.
5198 DiagnoseFunctionSpecifiers(D.getDeclSpec());
5200 if (D.getDeclSpec().isConstexprSpecified())
5201 Diag(D.getDeclSpec().getConstexprSpecLoc(), diag::err_invalid_constexpr)
5203 if (D.getDeclSpec().isConceptSpecified())
5204 Diag(D.getDeclSpec().getConceptSpecLoc(),
5205 diag::err_concept_wrong_decl_kind);
5207 if (D.getName().Kind != UnqualifiedId::IK_Identifier) {
5208 Diag(D.getName().StartLocation, diag::err_typedef_not_identifier)
5209 << D.getName().getSourceRange();
5213 TypedefDecl *NewTD = ParseTypedefDecl(S, D, TInfo->getType(), TInfo);
5214 if (!NewTD) return nullptr;
5216 // Handle attributes prior to checking for duplicates in MergeVarDecl
5217 ProcessDeclAttributes(S, NewTD, D);
5219 CheckTypedefForVariablyModifiedType(S, NewTD);
5221 bool Redeclaration = D.isRedeclaration();
5222 NamedDecl *ND = ActOnTypedefNameDecl(S, DC, NewTD, Previous, Redeclaration);
5223 D.setRedeclaration(Redeclaration);
5228 Sema::CheckTypedefForVariablyModifiedType(Scope *S, TypedefNameDecl *NewTD) {
5229 // C99 6.7.7p2: If a typedef name specifies a variably modified type
5230 // then it shall have block scope.
5231 // Note that variably modified types must be fixed before merging the decl so
5232 // that redeclarations will match.
5233 TypeSourceInfo *TInfo = NewTD->getTypeSourceInfo();
5234 QualType T = TInfo->getType();
5235 if (T->isVariablyModifiedType()) {
5236 getCurFunction()->setHasBranchProtectedScope();
5238 if (S->getFnParent() == nullptr) {
5239 bool SizeIsNegative;
5240 llvm::APSInt Oversized;
5241 TypeSourceInfo *FixedTInfo =
5242 TryToFixInvalidVariablyModifiedTypeSourceInfo(TInfo, Context,
5246 Diag(NewTD->getLocation(), diag::warn_illegal_constant_array_size);
5247 NewTD->setTypeSourceInfo(FixedTInfo);
5250 Diag(NewTD->getLocation(), diag::err_typecheck_negative_array_size);
5251 else if (T->isVariableArrayType())
5252 Diag(NewTD->getLocation(), diag::err_vla_decl_in_file_scope);
5253 else if (Oversized.getBoolValue())
5254 Diag(NewTD->getLocation(), diag::err_array_too_large)
5255 << Oversized.toString(10);
5257 Diag(NewTD->getLocation(), diag::err_vm_decl_in_file_scope);
5258 NewTD->setInvalidDecl();
5264 /// ActOnTypedefNameDecl - Perform semantic checking for a declaration which
5265 /// declares a typedef-name, either using the 'typedef' type specifier or via
5266 /// a C++0x [dcl.typedef]p2 alias-declaration: 'using T = A;'.
5268 Sema::ActOnTypedefNameDecl(Scope *S, DeclContext *DC, TypedefNameDecl *NewTD,
5269 LookupResult &Previous, bool &Redeclaration) {
5270 // Merge the decl with the existing one if appropriate. If the decl is
5271 // in an outer scope, it isn't the same thing.
5272 FilterLookupForScope(Previous, DC, S, /*ConsiderLinkage*/false,
5273 /*AllowInlineNamespace*/false);
5274 filterNonConflictingPreviousTypedefDecls(*this, NewTD, Previous);
5275 if (!Previous.empty()) {
5276 Redeclaration = true;
5277 MergeTypedefNameDecl(S, NewTD, Previous);
5280 // If this is the C FILE type, notify the AST context.
5281 if (IdentifierInfo *II = NewTD->getIdentifier())
5282 if (!NewTD->isInvalidDecl() &&
5283 NewTD->getDeclContext()->getRedeclContext()->isTranslationUnit()) {
5284 if (II->isStr("FILE"))
5285 Context.setFILEDecl(NewTD);
5286 else if (II->isStr("jmp_buf"))
5287 Context.setjmp_bufDecl(NewTD);
5288 else if (II->isStr("sigjmp_buf"))
5289 Context.setsigjmp_bufDecl(NewTD);
5290 else if (II->isStr("ucontext_t"))
5291 Context.setucontext_tDecl(NewTD);
5297 /// \brief Determines whether the given declaration is an out-of-scope
5298 /// previous declaration.
5300 /// This routine should be invoked when name lookup has found a
5301 /// previous declaration (PrevDecl) that is not in the scope where a
5302 /// new declaration by the same name is being introduced. If the new
5303 /// declaration occurs in a local scope, previous declarations with
5304 /// linkage may still be considered previous declarations (C99
5305 /// 6.2.2p4-5, C++ [basic.link]p6).
5307 /// \param PrevDecl the previous declaration found by name
5310 /// \param DC the context in which the new declaration is being
5313 /// \returns true if PrevDecl is an out-of-scope previous declaration
5314 /// for a new delcaration with the same name.
5316 isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC,
5317 ASTContext &Context) {
5321 if (!PrevDecl->hasLinkage())
5324 if (Context.getLangOpts().CPlusPlus) {
5325 // C++ [basic.link]p6:
5326 // If there is a visible declaration of an entity with linkage
5327 // having the same name and type, ignoring entities declared
5328 // outside the innermost enclosing namespace scope, the block
5329 // scope declaration declares that same entity and receives the
5330 // linkage of the previous declaration.
5331 DeclContext *OuterContext = DC->getRedeclContext();
5332 if (!OuterContext->isFunctionOrMethod())
5333 // This rule only applies to block-scope declarations.
5336 DeclContext *PrevOuterContext = PrevDecl->getDeclContext();
5337 if (PrevOuterContext->isRecord())
5338 // We found a member function: ignore it.
5341 // Find the innermost enclosing namespace for the new and
5342 // previous declarations.
5343 OuterContext = OuterContext->getEnclosingNamespaceContext();
5344 PrevOuterContext = PrevOuterContext->getEnclosingNamespaceContext();
5346 // The previous declaration is in a different namespace, so it
5347 // isn't the same function.
5348 if (!OuterContext->Equals(PrevOuterContext))
5355 static void SetNestedNameSpecifier(DeclaratorDecl *DD, Declarator &D) {
5356 CXXScopeSpec &SS = D.getCXXScopeSpec();
5357 if (!SS.isSet()) return;
5358 DD->setQualifierInfo(SS.getWithLocInContext(DD->getASTContext()));
5361 bool Sema::inferObjCARCLifetime(ValueDecl *decl) {
5362 QualType type = decl->getType();
5363 Qualifiers::ObjCLifetime lifetime = type.getObjCLifetime();
5364 if (lifetime == Qualifiers::OCL_Autoreleasing) {
5365 // Various kinds of declaration aren't allowed to be __autoreleasing.
5366 unsigned kind = -1U;
5367 if (VarDecl *var = dyn_cast<VarDecl>(decl)) {
5368 if (var->hasAttr<BlocksAttr>())
5369 kind = 0; // __block
5370 else if (!var->hasLocalStorage())
5372 } else if (isa<ObjCIvarDecl>(decl)) {
5374 } else if (isa<FieldDecl>(decl)) {
5379 Diag(decl->getLocation(), diag::err_arc_autoreleasing_var)
5382 } else if (lifetime == Qualifiers::OCL_None) {
5383 // Try to infer lifetime.
5384 if (!type->isObjCLifetimeType())
5387 lifetime = type->getObjCARCImplicitLifetime();
5388 type = Context.getLifetimeQualifiedType(type, lifetime);
5389 decl->setType(type);
5392 if (VarDecl *var = dyn_cast<VarDecl>(decl)) {
5393 // Thread-local variables cannot have lifetime.
5394 if (lifetime && lifetime != Qualifiers::OCL_ExplicitNone &&
5395 var->getTLSKind()) {
5396 Diag(var->getLocation(), diag::err_arc_thread_ownership)
5405 static void checkAttributesAfterMerging(Sema &S, NamedDecl &ND) {
5406 // Ensure that an auto decl is deduced otherwise the checks below might cache
5407 // the wrong linkage.
5408 assert(S.ParsingInitForAutoVars.count(&ND) == 0);
5410 // 'weak' only applies to declarations with external linkage.
5411 if (WeakAttr *Attr = ND.getAttr<WeakAttr>()) {
5412 if (!ND.isExternallyVisible()) {
5413 S.Diag(Attr->getLocation(), diag::err_attribute_weak_static);
5414 ND.dropAttr<WeakAttr>();
5417 if (WeakRefAttr *Attr = ND.getAttr<WeakRefAttr>()) {
5418 if (ND.isExternallyVisible()) {
5419 S.Diag(Attr->getLocation(), diag::err_attribute_weakref_not_static);
5420 ND.dropAttr<WeakRefAttr>();
5421 ND.dropAttr<AliasAttr>();
5425 if (auto *VD = dyn_cast<VarDecl>(&ND)) {
5426 if (VD->hasInit()) {
5427 if (const auto *Attr = VD->getAttr<AliasAttr>()) {
5428 assert(VD->isThisDeclarationADefinition() &&
5429 !VD->isExternallyVisible() && "Broken AliasAttr handled late!");
5430 S.Diag(Attr->getLocation(), diag::err_alias_is_definition) << VD;
5431 VD->dropAttr<AliasAttr>();
5436 // 'selectany' only applies to externally visible variable declarations.
5437 // It does not apply to functions.
5438 if (SelectAnyAttr *Attr = ND.getAttr<SelectAnyAttr>()) {
5439 if (isa<FunctionDecl>(ND) || !ND.isExternallyVisible()) {
5440 S.Diag(Attr->getLocation(),
5441 diag::err_attribute_selectany_non_extern_data);
5442 ND.dropAttr<SelectAnyAttr>();
5446 if (const InheritableAttr *Attr = getDLLAttr(&ND)) {
5447 // dll attributes require external linkage. Static locals may have external
5448 // linkage but still cannot be explicitly imported or exported.
5449 auto *VD = dyn_cast<VarDecl>(&ND);
5450 if (!ND.isExternallyVisible() || (VD && VD->isStaticLocal())) {
5451 S.Diag(ND.getLocation(), diag::err_attribute_dll_not_extern)
5453 ND.setInvalidDecl();
5457 // Virtual functions cannot be marked as 'notail'.
5458 if (auto *Attr = ND.getAttr<NotTailCalledAttr>())
5459 if (auto *MD = dyn_cast<CXXMethodDecl>(&ND))
5460 if (MD->isVirtual()) {
5461 S.Diag(ND.getLocation(),
5462 diag::err_invalid_attribute_on_virtual_function)
5464 ND.dropAttr<NotTailCalledAttr>();
5468 static void checkDLLAttributeRedeclaration(Sema &S, NamedDecl *OldDecl,
5470 bool IsSpecialization) {
5471 if (TemplateDecl *OldTD = dyn_cast<TemplateDecl>(OldDecl))
5472 OldDecl = OldTD->getTemplatedDecl();
5473 if (TemplateDecl *NewTD = dyn_cast<TemplateDecl>(NewDecl))
5474 NewDecl = NewTD->getTemplatedDecl();
5476 if (!OldDecl || !NewDecl)
5479 const DLLImportAttr *OldImportAttr = OldDecl->getAttr<DLLImportAttr>();
5480 const DLLExportAttr *OldExportAttr = OldDecl->getAttr<DLLExportAttr>();
5481 const DLLImportAttr *NewImportAttr = NewDecl->getAttr<DLLImportAttr>();
5482 const DLLExportAttr *NewExportAttr = NewDecl->getAttr<DLLExportAttr>();
5484 // dllimport and dllexport are inheritable attributes so we have to exclude
5485 // inherited attribute instances.
5486 bool HasNewAttr = (NewImportAttr && !NewImportAttr->isInherited()) ||
5487 (NewExportAttr && !NewExportAttr->isInherited());
5489 // A redeclaration is not allowed to add a dllimport or dllexport attribute,
5490 // the only exception being explicit specializations.
5491 // Implicitly generated declarations are also excluded for now because there
5492 // is no other way to switch these to use dllimport or dllexport.
5493 bool AddsAttr = !(OldImportAttr || OldExportAttr) && HasNewAttr;
5495 if (AddsAttr && !IsSpecialization && !OldDecl->isImplicit()) {
5496 // Allow with a warning for free functions and global variables.
5497 bool JustWarn = false;
5498 if (!OldDecl->isCXXClassMember()) {
5499 auto *VD = dyn_cast<VarDecl>(OldDecl);
5500 if (VD && !VD->getDescribedVarTemplate())
5502 auto *FD = dyn_cast<FunctionDecl>(OldDecl);
5503 if (FD && FD->getTemplatedKind() == FunctionDecl::TK_NonTemplate)
5507 // We cannot change a declaration that's been used because IR has already
5508 // been emitted. Dllimported functions will still work though (modulo
5509 // address equality) as they can use the thunk.
5510 if (OldDecl->isUsed())
5511 if (!isa<FunctionDecl>(OldDecl) || !NewImportAttr)
5514 unsigned DiagID = JustWarn ? diag::warn_attribute_dll_redeclaration
5515 : diag::err_attribute_dll_redeclaration;
5516 S.Diag(NewDecl->getLocation(), DiagID)
5518 << (NewImportAttr ? (const Attr *)NewImportAttr : NewExportAttr);
5519 S.Diag(OldDecl->getLocation(), diag::note_previous_declaration);
5521 NewDecl->setInvalidDecl();
5526 // A redeclaration is not allowed to drop a dllimport attribute, the only
5527 // exceptions being inline function definitions, local extern declarations,
5528 // and qualified friend declarations.
5529 // NB: MSVC converts such a declaration to dllexport.
5530 bool IsInline = false, IsStaticDataMember = false, IsQualifiedFriend = false;
5531 if (const auto *VD = dyn_cast<VarDecl>(NewDecl))
5532 // Ignore static data because out-of-line definitions are diagnosed
5534 IsStaticDataMember = VD->isStaticDataMember();
5535 else if (const auto *FD = dyn_cast<FunctionDecl>(NewDecl)) {
5536 IsInline = FD->isInlined();
5537 IsQualifiedFriend = FD->getQualifier() &&
5538 FD->getFriendObjectKind() == Decl::FOK_Declared;
5541 if (OldImportAttr && !HasNewAttr && !IsInline && !IsStaticDataMember &&
5542 !NewDecl->isLocalExternDecl() && !IsQualifiedFriend) {
5543 S.Diag(NewDecl->getLocation(),
5544 diag::warn_redeclaration_without_attribute_prev_attribute_ignored)
5545 << NewDecl << OldImportAttr;
5546 S.Diag(OldDecl->getLocation(), diag::note_previous_declaration);
5547 S.Diag(OldImportAttr->getLocation(), diag::note_previous_attribute);
5548 OldDecl->dropAttr<DLLImportAttr>();
5549 NewDecl->dropAttr<DLLImportAttr>();
5550 } else if (IsInline && OldImportAttr &&
5551 !S.Context.getTargetInfo().getCXXABI().isMicrosoft()) {
5552 // In MinGW, seeing a function declared inline drops the dllimport attribute.
5553 OldDecl->dropAttr<DLLImportAttr>();
5554 NewDecl->dropAttr<DLLImportAttr>();
5555 S.Diag(NewDecl->getLocation(),
5556 diag::warn_dllimport_dropped_from_inline_function)
5557 << NewDecl << OldImportAttr;
5561 /// Given that we are within the definition of the given function,
5562 /// will that definition behave like C99's 'inline', where the
5563 /// definition is discarded except for optimization purposes?
5564 static bool isFunctionDefinitionDiscarded(Sema &S, FunctionDecl *FD) {
5565 // Try to avoid calling GetGVALinkageForFunction.
5567 // All cases of this require the 'inline' keyword.
5568 if (!FD->isInlined()) return false;
5570 // This is only possible in C++ with the gnu_inline attribute.
5571 if (S.getLangOpts().CPlusPlus && !FD->hasAttr<GNUInlineAttr>())
5574 // Okay, go ahead and call the relatively-more-expensive function.
5577 // AST quite reasonably asserts that it's working on a function
5578 // definition. We don't really have a way to tell it that we're
5579 // currently defining the function, so just lie to it in +Asserts
5580 // builds. This is an awful hack.
5585 S.Context.GetGVALinkageForFunction(FD) == GVA_AvailableExternally;
5594 /// Determine whether a variable is extern "C" prior to attaching
5595 /// an initializer. We can't just call isExternC() here, because that
5596 /// will also compute and cache whether the declaration is externally
5597 /// visible, which might change when we attach the initializer.
5599 /// This can only be used if the declaration is known to not be a
5600 /// redeclaration of an internal linkage declaration.
5606 /// Attaching the initializer here makes this declaration not externally
5607 /// visible, because its type has internal linkage.
5609 /// FIXME: This is a hack.
5610 template<typename T>
5611 static bool isIncompleteDeclExternC(Sema &S, const T *D) {
5612 if (S.getLangOpts().CPlusPlus) {
5613 // In C++, the overloadable attribute negates the effects of extern "C".
5614 if (!D->isInExternCContext() || D->template hasAttr<OverloadableAttr>())
5617 // So do CUDA's host/device attributes if overloading is enabled.
5618 if (S.getLangOpts().CUDA && S.getLangOpts().CUDATargetOverloads &&
5619 (D->template hasAttr<CUDADeviceAttr>() ||
5620 D->template hasAttr<CUDAHostAttr>()))
5623 return D->isExternC();
5626 static bool shouldConsiderLinkage(const VarDecl *VD) {
5627 const DeclContext *DC = VD->getDeclContext()->getRedeclContext();
5628 if (DC->isFunctionOrMethod())
5629 return VD->hasExternalStorage();
5630 if (DC->isFileContext())
5634 llvm_unreachable("Unexpected context");
5637 static bool shouldConsiderLinkage(const FunctionDecl *FD) {
5638 const DeclContext *DC = FD->getDeclContext()->getRedeclContext();
5639 if (DC->isFileContext() || DC->isFunctionOrMethod())
5643 llvm_unreachable("Unexpected context");
5646 static bool hasParsedAttr(Scope *S, const AttributeList *AttrList,
5647 AttributeList::Kind Kind) {
5648 for (const AttributeList *L = AttrList; L; L = L->getNext())
5649 if (L->getKind() == Kind)
5654 static bool hasParsedAttr(Scope *S, const Declarator &PD,
5655 AttributeList::Kind Kind) {
5656 // Check decl attributes on the DeclSpec.
5657 if (hasParsedAttr(S, PD.getDeclSpec().getAttributes().getList(), Kind))
5660 // Walk the declarator structure, checking decl attributes that were in a type
5661 // position to the decl itself.
5662 for (unsigned I = 0, E = PD.getNumTypeObjects(); I != E; ++I) {
5663 if (hasParsedAttr(S, PD.getTypeObject(I).getAttrs(), Kind))
5667 // Finally, check attributes on the decl itself.
5668 return hasParsedAttr(S, PD.getAttributes(), Kind);
5671 /// Adjust the \c DeclContext for a function or variable that might be a
5672 /// function-local external declaration.
5673 bool Sema::adjustContextForLocalExternDecl(DeclContext *&DC) {
5674 if (!DC->isFunctionOrMethod())
5677 // If this is a local extern function or variable declared within a function
5678 // template, don't add it into the enclosing namespace scope until it is
5679 // instantiated; it might have a dependent type right now.
5680 if (DC->isDependentContext())
5683 // C++11 [basic.link]p7:
5684 // When a block scope declaration of an entity with linkage is not found to
5685 // refer to some other declaration, then that entity is a member of the
5686 // innermost enclosing namespace.
5688 // Per C++11 [namespace.def]p6, the innermost enclosing namespace is a
5689 // semantically-enclosing namespace, not a lexically-enclosing one.
5690 while (!DC->isFileContext() && !isa<LinkageSpecDecl>(DC))
5691 DC = DC->getParent();
5695 /// \brief Returns true if given declaration has external C language linkage.
5696 static bool isDeclExternC(const Decl *D) {
5697 if (const auto *FD = dyn_cast<FunctionDecl>(D))
5698 return FD->isExternC();
5699 if (const auto *VD = dyn_cast<VarDecl>(D))
5700 return VD->isExternC();
5702 llvm_unreachable("Unknown type of decl!");
5706 Sema::ActOnVariableDeclarator(Scope *S, Declarator &D, DeclContext *DC,
5707 TypeSourceInfo *TInfo, LookupResult &Previous,
5708 MultiTemplateParamsArg TemplateParamLists,
5710 QualType R = TInfo->getType();
5711 DeclarationName Name = GetNameForDeclarator(D).getName();
5713 DeclSpec::SCS SCSpec = D.getDeclSpec().getStorageClassSpec();
5714 StorageClass SC = StorageClassSpecToVarDeclStorageClass(D.getDeclSpec());
5716 // dllimport globals without explicit storage class are treated as extern. We
5717 // have to change the storage class this early to get the right DeclContext.
5718 if (SC == SC_None && !DC->isRecord() &&
5719 hasParsedAttr(S, D, AttributeList::AT_DLLImport) &&
5720 !hasParsedAttr(S, D, AttributeList::AT_DLLExport))
5723 DeclContext *OriginalDC = DC;
5724 bool IsLocalExternDecl = SC == SC_Extern &&
5725 adjustContextForLocalExternDecl(DC);
5727 if (getLangOpts().OpenCL) {
5728 // OpenCL v1.0 s6.8.a.3: Pointers to functions are not allowed.
5730 while (NR->isPointerType()) {
5731 if (NR->isFunctionPointerType()) {
5732 Diag(D.getIdentifierLoc(), diag::err_opencl_function_pointer_variable);
5736 NR = NR->getPointeeType();
5739 if (!getOpenCLOptions().cl_khr_fp16) {
5740 // OpenCL v1.2 s6.1.1.1: reject declaring variables of the half and
5741 // half array type (unless the cl_khr_fp16 extension is enabled).
5742 if (Context.getBaseElementType(R)->isHalfType()) {
5743 Diag(D.getIdentifierLoc(), diag::err_opencl_half_declaration) << R;
5749 if (SCSpec == DeclSpec::SCS_mutable) {
5750 // mutable can only appear on non-static class members, so it's always
5752 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember);
5757 if (getLangOpts().CPlusPlus11 && SCSpec == DeclSpec::SCS_register &&
5758 !D.getAsmLabel() && !getSourceManager().isInSystemMacro(
5759 D.getDeclSpec().getStorageClassSpecLoc())) {
5760 // In C++11, the 'register' storage class specifier is deprecated.
5761 // Suppress the warning in system macros, it's used in macros in some
5762 // popular C system headers, such as in glibc's htonl() macro.
5763 Diag(D.getDeclSpec().getStorageClassSpecLoc(),
5764 getLangOpts().CPlusPlus1z ? diag::ext_register_storage_class
5765 : diag::warn_deprecated_register)
5766 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc());
5769 IdentifierInfo *II = Name.getAsIdentifierInfo();
5771 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name)
5776 DiagnoseFunctionSpecifiers(D.getDeclSpec());
5778 if (!DC->isRecord() && S->getFnParent() == nullptr) {
5779 // C99 6.9p2: The storage-class specifiers auto and register shall not
5780 // appear in the declaration specifiers in an external declaration.
5781 // Global Register+Asm is a GNU extension we support.
5782 if (SC == SC_Auto || (SC == SC_Register && !D.getAsmLabel())) {
5783 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope);
5788 if (getLangOpts().OpenCL) {
5789 // OpenCL v1.2 s6.9.b p4:
5790 // The sampler type cannot be used with the __local and __global address
5791 // space qualifiers.
5792 if (R->isSamplerT() && (R.getAddressSpace() == LangAS::opencl_local ||
5793 R.getAddressSpace() == LangAS::opencl_global)) {
5794 Diag(D.getIdentifierLoc(), diag::err_wrong_sampler_addressspace);
5797 // OpenCL 1.2 spec, p6.9 r:
5798 // The event type cannot be used to declare a program scope variable.
5799 // The event type cannot be used with the __local, __constant and __global
5800 // address space qualifiers.
5801 if (R->isEventT()) {
5802 if (S->getParent() == nullptr) {
5803 Diag(D.getLocStart(), diag::err_event_t_global_var);
5807 if (R.getAddressSpace()) {
5808 Diag(D.getLocStart(), diag::err_event_t_addr_space_qual);
5814 bool IsExplicitSpecialization = false;
5815 bool IsVariableTemplateSpecialization = false;
5816 bool IsPartialSpecialization = false;
5817 bool IsVariableTemplate = false;
5818 VarDecl *NewVD = nullptr;
5819 VarTemplateDecl *NewTemplate = nullptr;
5820 TemplateParameterList *TemplateParams = nullptr;
5821 if (!getLangOpts().CPlusPlus) {
5822 NewVD = VarDecl::Create(Context, DC, D.getLocStart(),
5823 D.getIdentifierLoc(), II,
5826 if (D.getDeclSpec().containsPlaceholderType() && R->getContainedAutoType())
5827 ParsingInitForAutoVars.insert(NewVD);
5829 if (D.isInvalidType())
5830 NewVD->setInvalidDecl();
5832 bool Invalid = false;
5834 if (DC->isRecord() && !CurContext->isRecord()) {
5835 // This is an out-of-line definition of a static data member.
5840 Diag(D.getDeclSpec().getStorageClassSpecLoc(),
5841 diag::err_static_out_of_line)
5842 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc());
5847 // [dcl.stc] p2: The auto or register specifiers shall be applied only
5848 // to names of variables declared in a block or to function parameters.
5849 // [dcl.stc] p6: The extern specifier cannot be used in the declaration
5852 Diag(D.getDeclSpec().getStorageClassSpecLoc(),
5853 diag::err_storage_class_for_static_member)
5854 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc());
5856 case SC_PrivateExtern:
5857 llvm_unreachable("C storage class in c++!");
5861 if (SC == SC_Static && CurContext->isRecord()) {
5862 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) {
5863 if (RD->isLocalClass())
5864 Diag(D.getIdentifierLoc(),
5865 diag::err_static_data_member_not_allowed_in_local_class)
5866 << Name << RD->getDeclName();
5868 // C++98 [class.union]p1: If a union contains a static data member,
5869 // the program is ill-formed. C++11 drops this restriction.
5871 Diag(D.getIdentifierLoc(),
5872 getLangOpts().CPlusPlus11
5873 ? diag::warn_cxx98_compat_static_data_member_in_union
5874 : diag::ext_static_data_member_in_union) << Name;
5875 // We conservatively disallow static data members in anonymous structs.
5876 else if (!RD->getDeclName())
5877 Diag(D.getIdentifierLoc(),
5878 diag::err_static_data_member_not_allowed_in_anon_struct)
5879 << Name << RD->isUnion();
5883 // Match up the template parameter lists with the scope specifier, then
5884 // determine whether we have a template or a template specialization.
5885 TemplateParams = MatchTemplateParametersToScopeSpecifier(
5886 D.getDeclSpec().getLocStart(), D.getIdentifierLoc(),
5887 D.getCXXScopeSpec(),
5888 D.getName().getKind() == UnqualifiedId::IK_TemplateId
5889 ? D.getName().TemplateId
5892 /*never a friend*/ false, IsExplicitSpecialization, Invalid);
5894 if (TemplateParams) {
5895 if (!TemplateParams->size() &&
5896 D.getName().getKind() != UnqualifiedId::IK_TemplateId) {
5897 // There is an extraneous 'template<>' for this variable. Complain
5898 // about it, but allow the declaration of the variable.
5899 Diag(TemplateParams->getTemplateLoc(),
5900 diag::err_template_variable_noparams)
5902 << SourceRange(TemplateParams->getTemplateLoc(),
5903 TemplateParams->getRAngleLoc());
5904 TemplateParams = nullptr;
5906 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) {
5907 // This is an explicit specialization or a partial specialization.
5908 // FIXME: Check that we can declare a specialization here.
5909 IsVariableTemplateSpecialization = true;
5910 IsPartialSpecialization = TemplateParams->size() > 0;
5911 } else { // if (TemplateParams->size() > 0)
5912 // This is a template declaration.
5913 IsVariableTemplate = true;
5915 // Check that we can declare a template here.
5916 if (CheckTemplateDeclScope(S, TemplateParams))
5919 // Only C++1y supports variable templates (N3651).
5920 Diag(D.getIdentifierLoc(),
5921 getLangOpts().CPlusPlus14
5922 ? diag::warn_cxx11_compat_variable_template
5923 : diag::ext_variable_template);
5928 (Invalid || D.getName().getKind() != UnqualifiedId::IK_TemplateId) &&
5929 "should have a 'template<>' for this decl");
5932 if (IsVariableTemplateSpecialization) {
5933 SourceLocation TemplateKWLoc =
5934 TemplateParamLists.size() > 0
5935 ? TemplateParamLists[0]->getTemplateLoc()
5937 DeclResult Res = ActOnVarTemplateSpecialization(
5938 S, D, TInfo, TemplateKWLoc, TemplateParams, SC,
5939 IsPartialSpecialization);
5940 if (Res.isInvalid())
5942 NewVD = cast<VarDecl>(Res.get());
5945 NewVD = VarDecl::Create(Context, DC, D.getLocStart(),
5946 D.getIdentifierLoc(), II, R, TInfo, SC);
5948 // If this is supposed to be a variable template, create it as such.
5949 if (IsVariableTemplate) {
5951 VarTemplateDecl::Create(Context, DC, D.getIdentifierLoc(), Name,
5952 TemplateParams, NewVD);
5953 NewVD->setDescribedVarTemplate(NewTemplate);
5956 // If this decl has an auto type in need of deduction, make a note of the
5957 // Decl so we can diagnose uses of it in its own initializer.
5958 if (D.getDeclSpec().containsPlaceholderType() && R->getContainedAutoType())
5959 ParsingInitForAutoVars.insert(NewVD);
5961 if (D.isInvalidType() || Invalid) {
5962 NewVD->setInvalidDecl();
5964 NewTemplate->setInvalidDecl();
5967 SetNestedNameSpecifier(NewVD, D);
5969 // If we have any template parameter lists that don't directly belong to
5970 // the variable (matching the scope specifier), store them.
5971 unsigned VDTemplateParamLists = TemplateParams ? 1 : 0;
5972 if (TemplateParamLists.size() > VDTemplateParamLists)
5973 NewVD->setTemplateParameterListsInfo(
5974 Context, TemplateParamLists.drop_back(VDTemplateParamLists));
5976 if (D.getDeclSpec().isConstexprSpecified())
5977 NewVD->setConstexpr(true);
5979 if (D.getDeclSpec().isConceptSpecified()) {
5980 if (VarTemplateDecl *VTD = NewVD->getDescribedVarTemplate())
5983 // C++ Concepts TS [dcl.spec.concept]p2: A concept definition shall not
5984 // be declared with the thread_local, inline, friend, or constexpr
5985 // specifiers, [...]
5986 if (D.getDeclSpec().getThreadStorageClassSpec() == TSCS_thread_local) {
5987 Diag(D.getDeclSpec().getThreadStorageClassSpecLoc(),
5988 diag::err_concept_decl_invalid_specifiers)
5990 NewVD->setInvalidDecl(true);
5993 if (D.getDeclSpec().isConstexprSpecified()) {
5994 Diag(D.getDeclSpec().getConstexprSpecLoc(),
5995 diag::err_concept_decl_invalid_specifiers)
5997 NewVD->setInvalidDecl(true);
6000 // C++ Concepts TS [dcl.spec.concept]p1: The concept specifier shall be
6001 // applied only to the definition of a function template or variable
6002 // template, declared in namespace scope.
6003 if (IsVariableTemplateSpecialization) {
6004 Diag(D.getDeclSpec().getConceptSpecLoc(),
6005 diag::err_concept_specified_specialization)
6006 << (IsPartialSpecialization ? 2 : 1);
6009 // C++ Concepts TS [dcl.spec.concept]p6: A variable concept has the
6010 // following restrictions:
6011 // - The declared type shall have the type bool.
6012 if (!Context.hasSameType(NewVD->getType(), Context.BoolTy) &&
6013 !NewVD->isInvalidDecl()) {
6014 Diag(D.getIdentifierLoc(), diag::err_variable_concept_bool_decl);
6015 NewVD->setInvalidDecl(true);
6020 // Set the lexical context. If the declarator has a C++ scope specifier, the
6021 // lexical context will be different from the semantic context.
6022 NewVD->setLexicalDeclContext(CurContext);
6024 NewTemplate->setLexicalDeclContext(CurContext);
6026 if (IsLocalExternDecl)
6027 NewVD->setLocalExternDecl();
6029 bool EmitTLSUnsupportedError = false;
6030 if (DeclSpec::TSCS TSCS = D.getDeclSpec().getThreadStorageClassSpec()) {
6031 // C++11 [dcl.stc]p4:
6032 // When thread_local is applied to a variable of block scope the
6033 // storage-class-specifier static is implied if it does not appear
6035 // Core issue: 'static' is not implied if the variable is declared
6037 if (NewVD->hasLocalStorage() &&
6038 (SCSpec != DeclSpec::SCS_unspecified ||
6039 TSCS != DeclSpec::TSCS_thread_local ||
6040 !DC->isFunctionOrMethod()))
6041 Diag(D.getDeclSpec().getThreadStorageClassSpecLoc(),
6042 diag::err_thread_non_global)
6043 << DeclSpec::getSpecifierName(TSCS);
6044 else if (!Context.getTargetInfo().isTLSSupported()) {
6045 if (getLangOpts().CUDA) {
6046 // Postpone error emission until we've collected attributes required to
6047 // figure out whether it's a host or device variable and whether the
6048 // error should be ignored.
6049 EmitTLSUnsupportedError = true;
6050 // We still need to mark the variable as TLS so it shows up in AST with
6051 // proper storage class for other tools to use even if we're not going
6052 // to emit any code for it.
6053 NewVD->setTSCSpec(TSCS);
6055 Diag(D.getDeclSpec().getThreadStorageClassSpecLoc(),
6056 diag::err_thread_unsupported);
6058 NewVD->setTSCSpec(TSCS);
6062 // An inline definition of a function with external linkage shall
6063 // not contain a definition of a modifiable object with static or
6064 // thread storage duration...
6065 // We only apply this when the function is required to be defined
6066 // elsewhere, i.e. when the function is not 'extern inline'. Note
6067 // that a local variable with thread storage duration still has to
6068 // be marked 'static'. Also note that it's possible to get these
6069 // semantics in C++ using __attribute__((gnu_inline)).
6070 if (SC == SC_Static && S->getFnParent() != nullptr &&
6071 !NewVD->getType().isConstQualified()) {
6072 FunctionDecl *CurFD = getCurFunctionDecl();
6073 if (CurFD && isFunctionDefinitionDiscarded(*this, CurFD)) {
6074 Diag(D.getDeclSpec().getStorageClassSpecLoc(),
6075 diag::warn_static_local_in_extern_inline);
6076 MaybeSuggestAddingStaticToDecl(CurFD);
6080 if (D.getDeclSpec().isModulePrivateSpecified()) {
6081 if (IsVariableTemplateSpecialization)
6082 Diag(NewVD->getLocation(), diag::err_module_private_specialization)
6083 << (IsPartialSpecialization ? 1 : 0)
6084 << FixItHint::CreateRemoval(
6085 D.getDeclSpec().getModulePrivateSpecLoc());
6086 else if (IsExplicitSpecialization)
6087 Diag(NewVD->getLocation(), diag::err_module_private_specialization)
6089 << FixItHint::CreateRemoval(D.getDeclSpec().getModulePrivateSpecLoc());
6090 else if (NewVD->hasLocalStorage())
6091 Diag(NewVD->getLocation(), diag::err_module_private_local)
6092 << 0 << NewVD->getDeclName()
6093 << SourceRange(D.getDeclSpec().getModulePrivateSpecLoc())
6094 << FixItHint::CreateRemoval(D.getDeclSpec().getModulePrivateSpecLoc());
6096 NewVD->setModulePrivate();
6098 NewTemplate->setModulePrivate();
6102 // Handle attributes prior to checking for duplicates in MergeVarDecl
6103 ProcessDeclAttributes(S, NewVD, D);
6105 if (getLangOpts().CUDA) {
6106 if (EmitTLSUnsupportedError && DeclAttrsMatchCUDAMode(getLangOpts(), NewVD))
6107 Diag(D.getDeclSpec().getThreadStorageClassSpecLoc(),
6108 diag::err_thread_unsupported);
6109 // CUDA B.2.5: "__shared__ and __constant__ variables have implied static
6110 // storage [duration]."
6111 if (SC == SC_None && S->getFnParent() != nullptr &&
6112 (NewVD->hasAttr<CUDASharedAttr>() ||
6113 NewVD->hasAttr<CUDAConstantAttr>())) {
6114 NewVD->setStorageClass(SC_Static);
6118 // Ensure that dllimport globals without explicit storage class are treated as
6119 // extern. The storage class is set above using parsed attributes. Now we can
6120 // check the VarDecl itself.
6121 assert(!NewVD->hasAttr<DLLImportAttr>() ||
6122 NewVD->getAttr<DLLImportAttr>()->isInherited() ||
6123 NewVD->isStaticDataMember() || NewVD->getStorageClass() != SC_None);
6125 // In auto-retain/release, infer strong retension for variables of
6127 if (getLangOpts().ObjCAutoRefCount && inferObjCARCLifetime(NewVD))
6128 NewVD->setInvalidDecl();
6130 // Handle GNU asm-label extension (encoded as an attribute).
6131 if (Expr *E = (Expr*)D.getAsmLabel()) {
6132 // The parser guarantees this is a string.
6133 StringLiteral *SE = cast<StringLiteral>(E);
6134 StringRef Label = SE->getString();
6135 if (S->getFnParent() != nullptr) {
6139 Diag(E->getExprLoc(), diag::warn_asm_label_on_auto_decl) << Label;
6142 // Local Named register
6143 if (!Context.getTargetInfo().isValidGCCRegisterName(Label) &&
6144 DeclAttrsMatchCUDAMode(getLangOpts(), getCurFunctionDecl()))
6145 Diag(E->getExprLoc(), diag::err_asm_unknown_register_name) << Label;
6149 case SC_PrivateExtern:
6152 } else if (SC == SC_Register) {
6153 // Global Named register
6154 if (DeclAttrsMatchCUDAMode(getLangOpts(), NewVD)) {
6155 const auto &TI = Context.getTargetInfo();
6156 bool HasSizeMismatch;
6158 if (!TI.isValidGCCRegisterName(Label))
6159 Diag(E->getExprLoc(), diag::err_asm_unknown_register_name) << Label;
6160 else if (!TI.validateGlobalRegisterVariable(Label,
6161 Context.getTypeSize(R),
6163 Diag(E->getExprLoc(), diag::err_asm_invalid_global_var_reg) << Label;
6164 else if (HasSizeMismatch)
6165 Diag(E->getExprLoc(), diag::err_asm_register_size_mismatch) << Label;
6168 if (!R->isIntegralType(Context) && !R->isPointerType()) {
6169 Diag(D.getLocStart(), diag::err_asm_bad_register_type);
6170 NewVD->setInvalidDecl(true);
6174 NewVD->addAttr(::new (Context) AsmLabelAttr(SE->getStrTokenLoc(0),
6175 Context, Label, 0));
6176 } else if (!ExtnameUndeclaredIdentifiers.empty()) {
6177 llvm::DenseMap<IdentifierInfo*,AsmLabelAttr*>::iterator I =
6178 ExtnameUndeclaredIdentifiers.find(NewVD->getIdentifier());
6179 if (I != ExtnameUndeclaredIdentifiers.end()) {
6180 if (isDeclExternC(NewVD)) {
6181 NewVD->addAttr(I->second);
6182 ExtnameUndeclaredIdentifiers.erase(I);
6184 Diag(NewVD->getLocation(), diag::warn_redefine_extname_not_applied)
6185 << /*Variable*/1 << NewVD;
6189 // Diagnose shadowed variables before filtering for scope.
6190 if (D.getCXXScopeSpec().isEmpty())
6191 CheckShadow(S, NewVD, Previous);
6193 // Don't consider existing declarations that are in a different
6194 // scope and are out-of-semantic-context declarations (if the new
6195 // declaration has linkage).
6196 FilterLookupForScope(Previous, OriginalDC, S, shouldConsiderLinkage(NewVD),
6197 D.getCXXScopeSpec().isNotEmpty() ||
6198 IsExplicitSpecialization ||
6199 IsVariableTemplateSpecialization);
6201 // Check whether the previous declaration is in the same block scope. This
6202 // affects whether we merge types with it, per C++11 [dcl.array]p3.
6203 if (getLangOpts().CPlusPlus &&
6204 NewVD->isLocalVarDecl() && NewVD->hasExternalStorage())
6205 NewVD->setPreviousDeclInSameBlockScope(
6206 Previous.isSingleResult() && !Previous.isShadowed() &&
6207 isDeclInScope(Previous.getFoundDecl(), OriginalDC, S, false));
6209 if (!getLangOpts().CPlusPlus) {
6210 D.setRedeclaration(CheckVariableDeclaration(NewVD, Previous));
6212 // If this is an explicit specialization of a static data member, check it.
6213 if (IsExplicitSpecialization && !NewVD->isInvalidDecl() &&
6214 CheckMemberSpecialization(NewVD, Previous))
6215 NewVD->setInvalidDecl();
6217 // Merge the decl with the existing one if appropriate.
6218 if (!Previous.empty()) {
6219 if (Previous.isSingleResult() &&
6220 isa<FieldDecl>(Previous.getFoundDecl()) &&
6221 D.getCXXScopeSpec().isSet()) {
6222 // The user tried to define a non-static data member
6223 // out-of-line (C++ [dcl.meaning]p1).
6224 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line)
6225 << D.getCXXScopeSpec().getRange();
6227 NewVD->setInvalidDecl();
6229 } else if (D.getCXXScopeSpec().isSet()) {
6230 // No previous declaration in the qualifying scope.
6231 Diag(D.getIdentifierLoc(), diag::err_no_member)
6232 << Name << computeDeclContext(D.getCXXScopeSpec(), true)
6233 << D.getCXXScopeSpec().getRange();
6234 NewVD->setInvalidDecl();
6237 if (!IsVariableTemplateSpecialization)
6238 D.setRedeclaration(CheckVariableDeclaration(NewVD, Previous));
6241 VarTemplateDecl *PrevVarTemplate =
6242 NewVD->getPreviousDecl()
6243 ? NewVD->getPreviousDecl()->getDescribedVarTemplate()
6246 // Check the template parameter list of this declaration, possibly
6247 // merging in the template parameter list from the previous variable
6248 // template declaration.
6249 if (CheckTemplateParameterList(
6251 PrevVarTemplate ? PrevVarTemplate->getTemplateParameters()
6253 (D.getCXXScopeSpec().isSet() && DC && DC->isRecord() &&
6254 DC->isDependentContext())
6255 ? TPC_ClassTemplateMember
6257 NewVD->setInvalidDecl();
6259 // If we are providing an explicit specialization of a static variable
6260 // template, make a note of that.
6261 if (PrevVarTemplate &&
6262 PrevVarTemplate->getInstantiatedFromMemberTemplate())
6263 PrevVarTemplate->setMemberSpecialization();
6267 ProcessPragmaWeak(S, NewVD);
6269 // If this is the first declaration of an extern C variable, update
6270 // the map of such variables.
6271 if (NewVD->isFirstDecl() && !NewVD->isInvalidDecl() &&
6272 isIncompleteDeclExternC(*this, NewVD))
6273 RegisterLocallyScopedExternCDecl(NewVD, S);
6275 if (getLangOpts().CPlusPlus && NewVD->isStaticLocal()) {
6276 Decl *ManglingContextDecl;
6277 if (MangleNumberingContext *MCtx = getCurrentMangleNumberContext(
6278 NewVD->getDeclContext(), ManglingContextDecl)) {
6279 Context.setManglingNumber(
6280 NewVD, MCtx->getManglingNumber(
6281 NewVD, getMSManglingNumber(getLangOpts(), S)));
6282 Context.setStaticLocalNumber(NewVD, MCtx->getStaticLocalNumber(NewVD));
6286 // Special handling of variable named 'main'.
6287 if (Name.isIdentifier() && Name.getAsIdentifierInfo()->isStr("main") &&
6288 NewVD->getDeclContext()->getRedeclContext()->isTranslationUnit() &&
6289 !getLangOpts().Freestanding && !NewVD->getDescribedVarTemplate()) {
6291 // C++ [basic.start.main]p3
6292 // A program that declares a variable main at global scope is ill-formed.
6293 if (getLangOpts().CPlusPlus)
6294 Diag(D.getLocStart(), diag::err_main_global_variable);
6296 // In C, and external-linkage variable named main results in undefined
6298 else if (NewVD->hasExternalFormalLinkage())
6299 Diag(D.getLocStart(), diag::warn_main_redefined);
6302 if (D.isRedeclaration() && !Previous.empty()) {
6303 checkDLLAttributeRedeclaration(
6304 *this, dyn_cast<NamedDecl>(Previous.getRepresentativeDecl()), NewVD,
6305 IsExplicitSpecialization);
6309 if (NewVD->isInvalidDecl())
6310 NewTemplate->setInvalidDecl();
6311 ActOnDocumentableDecl(NewTemplate);
6318 /// \brief Diagnose variable or built-in function shadowing. Implements
6321 /// This method is called whenever a VarDecl is added to a "useful"
6324 /// \param S the scope in which the shadowing name is being declared
6325 /// \param R the lookup of the name
6327 void Sema::CheckShadow(Scope *S, VarDecl *D, const LookupResult& R) {
6328 // Return if warning is ignored.
6329 if (Diags.isIgnored(diag::warn_decl_shadow, R.getNameLoc()))
6332 // Don't diagnose declarations at file scope.
6333 if (D->hasGlobalStorage())
6336 DeclContext *NewDC = D->getDeclContext();
6338 // Only diagnose if we're shadowing an unambiguous field or variable.
6339 if (R.getResultKind() != LookupResult::Found)
6342 NamedDecl* ShadowedDecl = R.getFoundDecl();
6343 if (!isa<VarDecl>(ShadowedDecl) && !isa<FieldDecl>(ShadowedDecl))
6346 // Fields are not shadowed by variables in C++ static methods.
6347 if (isa<FieldDecl>(ShadowedDecl))
6348 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(NewDC))
6352 if (VarDecl *shadowedVar = dyn_cast<VarDecl>(ShadowedDecl))
6353 if (shadowedVar->isExternC()) {
6354 // For shadowing external vars, make sure that we point to the global
6355 // declaration, not a locally scoped extern declaration.
6356 for (auto I : shadowedVar->redecls())
6357 if (I->isFileVarDecl()) {
6363 DeclContext *OldDC = ShadowedDecl->getDeclContext();
6365 // Only warn about certain kinds of shadowing for class members.
6366 if (NewDC && NewDC->isRecord()) {
6367 // In particular, don't warn about shadowing non-class members.
6368 if (!OldDC->isRecord())
6371 // TODO: should we warn about static data members shadowing
6372 // static data members from base classes?
6374 // TODO: don't diagnose for inaccessible shadowed members.
6375 // This is hard to do perfectly because we might friend the
6376 // shadowing context, but that's just a false negative.
6379 // Determine what kind of declaration we're shadowing.
6381 if (isa<RecordDecl>(OldDC)) {
6382 if (isa<FieldDecl>(ShadowedDecl))
6385 Kind = 2; // static data member
6386 } else if (OldDC->isFileContext())
6391 DeclarationName Name = R.getLookupName();
6393 // Emit warning and note.
6394 if (getSourceManager().isInSystemMacro(R.getNameLoc()))
6396 Diag(R.getNameLoc(), diag::warn_decl_shadow) << Name << Kind << OldDC;
6397 Diag(ShadowedDecl->getLocation(), diag::note_previous_declaration);
6400 /// \brief Check -Wshadow without the advantage of a previous lookup.
6401 void Sema::CheckShadow(Scope *S, VarDecl *D) {
6402 if (Diags.isIgnored(diag::warn_decl_shadow, D->getLocation()))
6405 LookupResult R(*this, D->getDeclName(), D->getLocation(),
6406 Sema::LookupOrdinaryName, Sema::ForRedeclaration);
6408 CheckShadow(S, D, R);
6411 /// Check for conflict between this global or extern "C" declaration and
6412 /// previous global or extern "C" declarations. This is only used in C++.
6413 template<typename T>
6414 static bool checkGlobalOrExternCConflict(
6415 Sema &S, const T *ND, bool IsGlobal, LookupResult &Previous) {
6416 assert(S.getLangOpts().CPlusPlus && "only C++ has extern \"C\"");
6417 NamedDecl *Prev = S.findLocallyScopedExternCDecl(ND->getDeclName());
6419 if (!Prev && IsGlobal && !isIncompleteDeclExternC(S, ND)) {
6420 // The common case: this global doesn't conflict with any extern "C"
6426 if (!IsGlobal || isIncompleteDeclExternC(S, ND)) {
6427 // Both the old and new declarations have C language linkage. This is a
6430 Previous.addDecl(Prev);
6434 // This is a global, non-extern "C" declaration, and there is a previous
6435 // non-global extern "C" declaration. Diagnose if this is a variable
6437 if (!isa<VarDecl>(ND))
6440 // The declaration is extern "C". Check for any declaration in the
6441 // translation unit which might conflict.
6443 // We have already performed the lookup into the translation unit.
6445 for (LookupResult::iterator I = Previous.begin(), E = Previous.end();
6447 if (isa<VarDecl>(*I)) {
6453 DeclContext::lookup_result R =
6454 S.Context.getTranslationUnitDecl()->lookup(ND->getDeclName());
6455 for (DeclContext::lookup_result::iterator I = R.begin(), E = R.end();
6457 if (isa<VarDecl>(*I)) {
6461 // FIXME: If we have any other entity with this name in global scope,
6462 // the declaration is ill-formed, but that is a defect: it breaks the
6463 // 'stat' hack, for instance. Only variables can have mangled name
6464 // clashes with extern "C" declarations, so only they deserve a
6473 // Use the first declaration's location to ensure we point at something which
6474 // is lexically inside an extern "C" linkage-spec.
6475 assert(Prev && "should have found a previous declaration to diagnose");
6476 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(Prev))
6477 Prev = FD->getFirstDecl();
6479 Prev = cast<VarDecl>(Prev)->getFirstDecl();
6481 S.Diag(ND->getLocation(), diag::err_extern_c_global_conflict)
6483 S.Diag(Prev->getLocation(), diag::note_extern_c_global_conflict)
6488 /// Apply special rules for handling extern "C" declarations. Returns \c true
6489 /// if we have found that this is a redeclaration of some prior entity.
6491 /// Per C++ [dcl.link]p6:
6492 /// Two declarations [for a function or variable] with C language linkage
6493 /// with the same name that appear in different scopes refer to the same
6494 /// [entity]. An entity with C language linkage shall not be declared with
6495 /// the same name as an entity in global scope.
6496 template<typename T>
6497 static bool checkForConflictWithNonVisibleExternC(Sema &S, const T *ND,
6498 LookupResult &Previous) {
6499 if (!S.getLangOpts().CPlusPlus) {
6500 // In C, when declaring a global variable, look for a corresponding 'extern'
6501 // variable declared in function scope. We don't need this in C++, because
6502 // we find local extern decls in the surrounding file-scope DeclContext.
6503 if (ND->getDeclContext()->getRedeclContext()->isTranslationUnit()) {
6504 if (NamedDecl *Prev = S.findLocallyScopedExternCDecl(ND->getDeclName())) {
6506 Previous.addDecl(Prev);
6513 // A declaration in the translation unit can conflict with an extern "C"
6515 if (ND->getDeclContext()->getRedeclContext()->isTranslationUnit())
6516 return checkGlobalOrExternCConflict(S, ND, /*IsGlobal*/true, Previous);
6518 // An extern "C" declaration can conflict with a declaration in the
6519 // translation unit or can be a redeclaration of an extern "C" declaration
6520 // in another scope.
6521 if (isIncompleteDeclExternC(S,ND))
6522 return checkGlobalOrExternCConflict(S, ND, /*IsGlobal*/false, Previous);
6524 // Neither global nor extern "C": nothing to do.
6528 void Sema::CheckVariableDeclarationType(VarDecl *NewVD) {
6529 // If the decl is already known invalid, don't check it.
6530 if (NewVD->isInvalidDecl())
6533 TypeSourceInfo *TInfo = NewVD->getTypeSourceInfo();
6534 QualType T = TInfo->getType();
6536 // Defer checking an 'auto' type until its initializer is attached.
6537 if (T->isUndeducedType())
6540 if (NewVD->hasAttrs())
6541 CheckAlignasUnderalignment(NewVD);
6543 if (T->isObjCObjectType()) {
6544 Diag(NewVD->getLocation(), diag::err_statically_allocated_object)
6545 << FixItHint::CreateInsertion(NewVD->getLocation(), "*");
6546 T = Context.getObjCObjectPointerType(T);
6550 // Emit an error if an address space was applied to decl with local storage.
6551 // This includes arrays of objects with address space qualifiers, but not
6552 // automatic variables that point to other address spaces.
6553 // ISO/IEC TR 18037 S5.1.2
6554 if (!getLangOpts().OpenCL
6555 && NewVD->hasLocalStorage() && T.getAddressSpace() != 0) {
6556 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl);
6557 NewVD->setInvalidDecl();
6561 // OpenCL v1.2 s6.8 -- The static qualifier is valid only in program
6563 if (getLangOpts().OpenCLVersion == 120 &&
6564 !getOpenCLOptions().cl_clang_storage_class_specifiers &&
6565 NewVD->isStaticLocal()) {
6566 Diag(NewVD->getLocation(), diag::err_static_function_scope);
6567 NewVD->setInvalidDecl();
6571 // OpenCL v1.2 s6.5 - All program scope variables must be declared in the
6572 // __constant address space.
6573 // OpenCL v2.0 s6.5.1 - Variables defined at program scope and static
6574 // variables inside a function can also be declared in the global
6576 if (getLangOpts().OpenCL) {
6577 if (NewVD->isFileVarDecl()) {
6578 if (!T->isSamplerT() &&
6579 !(T.getAddressSpace() == LangAS::opencl_constant ||
6580 (T.getAddressSpace() == LangAS::opencl_global &&
6581 getLangOpts().OpenCLVersion == 200))) {
6582 if (getLangOpts().OpenCLVersion == 200)
6583 Diag(NewVD->getLocation(), diag::err_opencl_global_invalid_addr_space)
6584 << "global or constant";
6586 Diag(NewVD->getLocation(), diag::err_opencl_global_invalid_addr_space)
6588 NewVD->setInvalidDecl();
6592 // OpenCL v2.0 s6.5.1 - Variables defined at program scope and static
6593 // variables inside a function can also be declared in the global
6595 if (NewVD->isStaticLocal() &&
6596 !(T.getAddressSpace() == LangAS::opencl_constant ||
6597 (T.getAddressSpace() == LangAS::opencl_global &&
6598 getLangOpts().OpenCLVersion == 200))) {
6599 if (getLangOpts().OpenCLVersion == 200)
6600 Diag(NewVD->getLocation(), diag::err_opencl_global_invalid_addr_space)
6601 << "global or constant";
6603 Diag(NewVD->getLocation(), diag::err_opencl_global_invalid_addr_space)
6605 NewVD->setInvalidDecl();
6608 // OpenCL v1.1 s6.5.2 and s6.5.3 no local or constant variables
6610 if (T.getAddressSpace() == LangAS::opencl_constant ||
6611 T.getAddressSpace() == LangAS::opencl_local) {
6612 FunctionDecl *FD = getCurFunctionDecl();
6613 if (FD && !FD->hasAttr<OpenCLKernelAttr>()) {
6614 if (T.getAddressSpace() == LangAS::opencl_constant)
6615 Diag(NewVD->getLocation(), diag::err_opencl_non_kernel_variable)
6618 Diag(NewVD->getLocation(), diag::err_opencl_non_kernel_variable)
6620 NewVD->setInvalidDecl();
6627 if (NewVD->hasLocalStorage() && T.isObjCGCWeak()
6628 && !NewVD->hasAttr<BlocksAttr>()) {
6629 if (getLangOpts().getGC() != LangOptions::NonGC)
6630 Diag(NewVD->getLocation(), diag::warn_gc_attribute_weak_on_local);
6632 assert(!getLangOpts().ObjCAutoRefCount);
6633 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local);
6637 bool isVM = T->isVariablyModifiedType();
6638 if (isVM || NewVD->hasAttr<CleanupAttr>() ||
6639 NewVD->hasAttr<BlocksAttr>())
6640 getCurFunction()->setHasBranchProtectedScope();
6642 if ((isVM && NewVD->hasLinkage()) ||
6643 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) {
6644 bool SizeIsNegative;
6645 llvm::APSInt Oversized;
6646 TypeSourceInfo *FixedTInfo =
6647 TryToFixInvalidVariablyModifiedTypeSourceInfo(TInfo, Context,
6648 SizeIsNegative, Oversized);
6649 if (!FixedTInfo && T->isVariableArrayType()) {
6650 const VariableArrayType *VAT = Context.getAsVariableArrayType(T);
6651 // FIXME: This won't give the correct result for
6653 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange();
6655 if (NewVD->isFileVarDecl())
6656 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope)
6658 else if (NewVD->isStaticLocal())
6659 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage)
6662 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage)
6664 NewVD->setInvalidDecl();
6669 if (NewVD->isFileVarDecl())
6670 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope);
6672 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage);
6673 NewVD->setInvalidDecl();
6677 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size);
6678 NewVD->setType(FixedTInfo->getType());
6679 NewVD->setTypeSourceInfo(FixedTInfo);
6682 if (T->isVoidType()) {
6683 // C++98 [dcl.stc]p5: The extern specifier can be applied only to the names
6684 // of objects and functions.
6685 if (NewVD->isThisDeclarationADefinition() || getLangOpts().CPlusPlus) {
6686 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type)
6688 NewVD->setInvalidDecl();
6693 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) {
6694 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal);
6695 NewVD->setInvalidDecl();
6699 if (isVM && NewVD->hasAttr<BlocksAttr>()) {
6700 Diag(NewVD->getLocation(), diag::err_block_on_vm);
6701 NewVD->setInvalidDecl();
6705 if (NewVD->isConstexpr() && !T->isDependentType() &&
6706 RequireLiteralType(NewVD->getLocation(), T,
6707 diag::err_constexpr_var_non_literal)) {
6708 NewVD->setInvalidDecl();
6713 /// \brief Perform semantic checking on a newly-created variable
6716 /// This routine performs all of the type-checking required for a
6717 /// variable declaration once it has been built. It is used both to
6718 /// check variables after they have been parsed and their declarators
6719 /// have been translated into a declaration, and to check variables
6720 /// that have been instantiated from a template.
6722 /// Sets NewVD->isInvalidDecl() if an error was encountered.
6724 /// Returns true if the variable declaration is a redeclaration.
6725 bool Sema::CheckVariableDeclaration(VarDecl *NewVD, LookupResult &Previous) {
6726 CheckVariableDeclarationType(NewVD);
6728 // If the decl is already known invalid, don't check it.
6729 if (NewVD->isInvalidDecl())
6732 // If we did not find anything by this name, look for a non-visible
6733 // extern "C" declaration with the same name.
6734 if (Previous.empty() &&
6735 checkForConflictWithNonVisibleExternC(*this, NewVD, Previous))
6736 Previous.setShadowed();
6738 if (!Previous.empty()) {
6739 MergeVarDecl(NewVD, Previous);
6746 struct FindOverriddenMethod {
6748 CXXMethodDecl *Method;
6750 /// Member lookup function that determines whether a given C++
6751 /// method overrides a method in a base class, to be used with
6752 /// CXXRecordDecl::lookupInBases().
6753 bool operator()(const CXXBaseSpecifier *Specifier, CXXBasePath &Path) {
6754 RecordDecl *BaseRecord =
6755 Specifier->getType()->getAs<RecordType>()->getDecl();
6757 DeclarationName Name = Method->getDeclName();
6759 // FIXME: Do we care about other names here too?
6760 if (Name.getNameKind() == DeclarationName::CXXDestructorName) {
6761 // We really want to find the base class destructor here.
6762 QualType T = S->Context.getTypeDeclType(BaseRecord);
6763 CanQualType CT = S->Context.getCanonicalType(T);
6765 Name = S->Context.DeclarationNames.getCXXDestructorName(CT);
6768 for (Path.Decls = BaseRecord->lookup(Name); !Path.Decls.empty();
6769 Path.Decls = Path.Decls.slice(1)) {
6770 NamedDecl *D = Path.Decls.front();
6771 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(D)) {
6772 if (MD->isVirtual() && !S->IsOverload(Method, MD, false))
6781 enum OverrideErrorKind { OEK_All, OEK_NonDeleted, OEK_Deleted };
6782 } // end anonymous namespace
6784 /// \brief Report an error regarding overriding, along with any relevant
6785 /// overriden methods.
6787 /// \param DiagID the primary error to report.
6788 /// \param MD the overriding method.
6789 /// \param OEK which overrides to include as notes.
6790 static void ReportOverrides(Sema& S, unsigned DiagID, const CXXMethodDecl *MD,
6791 OverrideErrorKind OEK = OEK_All) {
6792 S.Diag(MD->getLocation(), DiagID) << MD->getDeclName();
6793 for (CXXMethodDecl::method_iterator I = MD->begin_overridden_methods(),
6794 E = MD->end_overridden_methods();
6796 // This check (& the OEK parameter) could be replaced by a predicate, but
6797 // without lambdas that would be overkill. This is still nicer than writing
6798 // out the diag loop 3 times.
6799 if ((OEK == OEK_All) ||
6800 (OEK == OEK_NonDeleted && !(*I)->isDeleted()) ||
6801 (OEK == OEK_Deleted && (*I)->isDeleted()))
6802 S.Diag((*I)->getLocation(), diag::note_overridden_virtual_function);
6806 /// AddOverriddenMethods - See if a method overrides any in the base classes,
6807 /// and if so, check that it's a valid override and remember it.
6808 bool Sema::AddOverriddenMethods(CXXRecordDecl *DC, CXXMethodDecl *MD) {
6809 // Look for methods in base classes that this method might override.
6811 FindOverriddenMethod FOM;
6814 bool hasDeletedOverridenMethods = false;
6815 bool hasNonDeletedOverridenMethods = false;
6816 bool AddedAny = false;
6817 if (DC->lookupInBases(FOM, Paths)) {
6818 for (auto *I : Paths.found_decls()) {
6819 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(I)) {
6820 MD->addOverriddenMethod(OldMD->getCanonicalDecl());
6821 if (!CheckOverridingFunctionReturnType(MD, OldMD) &&
6822 !CheckOverridingFunctionAttributes(MD, OldMD) &&
6823 !CheckOverridingFunctionExceptionSpec(MD, OldMD) &&
6824 !CheckIfOverriddenFunctionIsMarkedFinal(MD, OldMD)) {
6825 hasDeletedOverridenMethods |= OldMD->isDeleted();
6826 hasNonDeletedOverridenMethods |= !OldMD->isDeleted();
6833 if (hasDeletedOverridenMethods && !MD->isDeleted()) {
6834 ReportOverrides(*this, diag::err_non_deleted_override, MD, OEK_Deleted);
6836 if (hasNonDeletedOverridenMethods && MD->isDeleted()) {
6837 ReportOverrides(*this, diag::err_deleted_override, MD, OEK_NonDeleted);
6844 // Struct for holding all of the extra arguments needed by
6845 // DiagnoseInvalidRedeclaration to call Sema::ActOnFunctionDeclarator.
6846 struct ActOnFDArgs {
6849 MultiTemplateParamsArg TemplateParamLists;
6852 } // end anonymous namespace
6856 // Callback to only accept typo corrections that have a non-zero edit distance.
6857 // Also only accept corrections that have the same parent decl.
6858 class DifferentNameValidatorCCC : public CorrectionCandidateCallback {
6860 DifferentNameValidatorCCC(ASTContext &Context, FunctionDecl *TypoFD,
6861 CXXRecordDecl *Parent)
6862 : Context(Context), OriginalFD(TypoFD),
6863 ExpectedParent(Parent ? Parent->getCanonicalDecl() : nullptr) {}
6865 bool ValidateCandidate(const TypoCorrection &candidate) override {
6866 if (candidate.getEditDistance() == 0)
6869 SmallVector<unsigned, 1> MismatchedParams;
6870 for (TypoCorrection::const_decl_iterator CDecl = candidate.begin(),
6871 CDeclEnd = candidate.end();
6872 CDecl != CDeclEnd; ++CDecl) {
6873 FunctionDecl *FD = dyn_cast<FunctionDecl>(*CDecl);
6875 if (FD && !FD->hasBody() &&
6876 hasSimilarParameters(Context, FD, OriginalFD, MismatchedParams)) {
6877 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) {
6878 CXXRecordDecl *Parent = MD->getParent();
6879 if (Parent && Parent->getCanonicalDecl() == ExpectedParent)
6881 } else if (!ExpectedParent) {
6891 ASTContext &Context;
6892 FunctionDecl *OriginalFD;
6893 CXXRecordDecl *ExpectedParent;
6896 } // end anonymous namespace
6898 /// \brief Generate diagnostics for an invalid function redeclaration.
6900 /// This routine handles generating the diagnostic messages for an invalid
6901 /// function redeclaration, including finding possible similar declarations
6902 /// or performing typo correction if there are no previous declarations with
6905 /// Returns a NamedDecl iff typo correction was performed and substituting in
6906 /// the new declaration name does not cause new errors.
6907 static NamedDecl *DiagnoseInvalidRedeclaration(
6908 Sema &SemaRef, LookupResult &Previous, FunctionDecl *NewFD,
6909 ActOnFDArgs &ExtraArgs, bool IsLocalFriend, Scope *S) {
6910 DeclarationName Name = NewFD->getDeclName();
6911 DeclContext *NewDC = NewFD->getDeclContext();
6912 SmallVector<unsigned, 1> MismatchedParams;
6913 SmallVector<std::pair<FunctionDecl *, unsigned>, 1> NearMatches;
6914 TypoCorrection Correction;
6915 bool IsDefinition = ExtraArgs.D.isFunctionDefinition();
6916 unsigned DiagMsg = IsLocalFriend ? diag::err_no_matching_local_friend
6917 : diag::err_member_decl_does_not_match;
6918 LookupResult Prev(SemaRef, Name, NewFD->getLocation(),
6919 IsLocalFriend ? Sema::LookupLocalFriendName
6920 : Sema::LookupOrdinaryName,
6921 Sema::ForRedeclaration);
6923 NewFD->setInvalidDecl();
6925 SemaRef.LookupName(Prev, S);
6927 SemaRef.LookupQualifiedName(Prev, NewDC);
6928 assert(!Prev.isAmbiguous() &&
6929 "Cannot have an ambiguity in previous-declaration lookup");
6930 CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(NewFD);
6931 if (!Prev.empty()) {
6932 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end();
6933 Func != FuncEnd; ++Func) {
6934 FunctionDecl *FD = dyn_cast<FunctionDecl>(*Func);
6936 hasSimilarParameters(SemaRef.Context, FD, NewFD, MismatchedParams)) {
6937 // Add 1 to the index so that 0 can mean the mismatch didn't
6938 // involve a parameter
6940 MismatchedParams.empty() ? 0 : MismatchedParams.front() + 1;
6941 NearMatches.push_back(std::make_pair(FD, ParamNum));
6944 // If the qualified name lookup yielded nothing, try typo correction
6945 } else if ((Correction = SemaRef.CorrectTypo(
6946 Prev.getLookupNameInfo(), Prev.getLookupKind(), S,
6947 &ExtraArgs.D.getCXXScopeSpec(),
6948 llvm::make_unique<DifferentNameValidatorCCC>(
6949 SemaRef.Context, NewFD, MD ? MD->getParent() : nullptr),
6950 Sema::CTK_ErrorRecovery, IsLocalFriend ? nullptr : NewDC))) {
6951 // Set up everything for the call to ActOnFunctionDeclarator
6952 ExtraArgs.D.SetIdentifier(Correction.getCorrectionAsIdentifierInfo(),
6953 ExtraArgs.D.getIdentifierLoc());
6955 Previous.setLookupName(Correction.getCorrection());
6956 for (TypoCorrection::decl_iterator CDecl = Correction.begin(),
6957 CDeclEnd = Correction.end();
6958 CDecl != CDeclEnd; ++CDecl) {
6959 FunctionDecl *FD = dyn_cast<FunctionDecl>(*CDecl);
6960 if (FD && !FD->hasBody() &&
6961 hasSimilarParameters(SemaRef.Context, FD, NewFD, MismatchedParams)) {
6962 Previous.addDecl(FD);
6965 bool wasRedeclaration = ExtraArgs.D.isRedeclaration();
6968 // Retry building the function declaration with the new previous
6969 // declarations, and with errors suppressed.
6972 Sema::SFINAETrap Trap(SemaRef);
6974 // TODO: Refactor ActOnFunctionDeclarator so that we can call only the
6975 // pieces need to verify the typo-corrected C++ declaration and hopefully
6976 // eliminate the need for the parameter pack ExtraArgs.
6977 Result = SemaRef.ActOnFunctionDeclarator(
6978 ExtraArgs.S, ExtraArgs.D,
6979 Correction.getCorrectionDecl()->getDeclContext(),
6980 NewFD->getTypeSourceInfo(), Previous, ExtraArgs.TemplateParamLists,
6981 ExtraArgs.AddToScope);
6983 if (Trap.hasErrorOccurred())
6988 // Determine which correction we picked.
6989 Decl *Canonical = Result->getCanonicalDecl();
6990 for (LookupResult::iterator I = Previous.begin(), E = Previous.end();
6992 if ((*I)->getCanonicalDecl() == Canonical)
6993 Correction.setCorrectionDecl(*I);
6995 SemaRef.diagnoseTypo(
6997 SemaRef.PDiag(IsLocalFriend
6998 ? diag::err_no_matching_local_friend_suggest
6999 : diag::err_member_decl_does_not_match_suggest)
7000 << Name << NewDC << IsDefinition);
7004 // Pretend the typo correction never occurred
7005 ExtraArgs.D.SetIdentifier(Name.getAsIdentifierInfo(),
7006 ExtraArgs.D.getIdentifierLoc());
7007 ExtraArgs.D.setRedeclaration(wasRedeclaration);
7009 Previous.setLookupName(Name);
7012 SemaRef.Diag(NewFD->getLocation(), DiagMsg)
7013 << Name << NewDC << IsDefinition << NewFD->getLocation();
7015 bool NewFDisConst = false;
7016 if (CXXMethodDecl *NewMD = dyn_cast<CXXMethodDecl>(NewFD))
7017 NewFDisConst = NewMD->isConst();
7019 for (SmallVectorImpl<std::pair<FunctionDecl *, unsigned> >::iterator
7020 NearMatch = NearMatches.begin(), NearMatchEnd = NearMatches.end();
7021 NearMatch != NearMatchEnd; ++NearMatch) {
7022 FunctionDecl *FD = NearMatch->first;
7023 CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD);
7024 bool FDisConst = MD && MD->isConst();
7025 bool IsMember = MD || !IsLocalFriend;
7027 // FIXME: These notes are poorly worded for the local friend case.
7028 if (unsigned Idx = NearMatch->second) {
7029 ParmVarDecl *FDParam = FD->getParamDecl(Idx-1);
7030 SourceLocation Loc = FDParam->getTypeSpecStartLoc();
7031 if (Loc.isInvalid()) Loc = FD->getLocation();
7032 SemaRef.Diag(Loc, IsMember ? diag::note_member_def_close_param_match
7033 : diag::note_local_decl_close_param_match)
7034 << Idx << FDParam->getType()
7035 << NewFD->getParamDecl(Idx - 1)->getType();
7036 } else if (FDisConst != NewFDisConst) {
7037 SemaRef.Diag(FD->getLocation(), diag::note_member_def_close_const_match)
7038 << NewFDisConst << FD->getSourceRange().getEnd();
7040 SemaRef.Diag(FD->getLocation(),
7041 IsMember ? diag::note_member_def_close_match
7042 : diag::note_local_decl_close_match);
7047 static StorageClass getFunctionStorageClass(Sema &SemaRef, Declarator &D) {
7048 switch (D.getDeclSpec().getStorageClassSpec()) {
7049 default: llvm_unreachable("Unknown storage class!");
7050 case DeclSpec::SCS_auto:
7051 case DeclSpec::SCS_register:
7052 case DeclSpec::SCS_mutable:
7053 SemaRef.Diag(D.getDeclSpec().getStorageClassSpecLoc(),
7054 diag::err_typecheck_sclass_func);
7057 case DeclSpec::SCS_unspecified: break;
7058 case DeclSpec::SCS_extern:
7059 if (D.getDeclSpec().isExternInLinkageSpec())
7062 case DeclSpec::SCS_static: {
7063 if (SemaRef.CurContext->getRedeclContext()->isFunctionOrMethod()) {
7065 // The declaration of an identifier for a function that has
7066 // block scope shall have no explicit storage-class specifier
7067 // other than extern
7068 // See also (C++ [dcl.stc]p4).
7069 SemaRef.Diag(D.getDeclSpec().getStorageClassSpecLoc(),
7070 diag::err_static_block_func);
7075 case DeclSpec::SCS_private_extern: return SC_PrivateExtern;
7078 // No explicit storage class has already been returned
7082 static FunctionDecl* CreateNewFunctionDecl(Sema &SemaRef, Declarator &D,
7083 DeclContext *DC, QualType &R,
7084 TypeSourceInfo *TInfo,
7086 bool &IsVirtualOkay) {
7087 DeclarationNameInfo NameInfo = SemaRef.GetNameForDeclarator(D);
7088 DeclarationName Name = NameInfo.getName();
7090 FunctionDecl *NewFD = nullptr;
7091 bool isInline = D.getDeclSpec().isInlineSpecified();
7093 if (!SemaRef.getLangOpts().CPlusPlus) {
7094 // Determine whether the function was written with a
7095 // prototype. This true when:
7096 // - there is a prototype in the declarator, or
7097 // - the type R of the function is some kind of typedef or other reference
7098 // to a type name (which eventually refers to a function type).
7100 (D.isFunctionDeclarator() && D.getFunctionTypeInfo().hasPrototype) ||
7101 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType());
7103 NewFD = FunctionDecl::Create(SemaRef.Context, DC,
7104 D.getLocStart(), NameInfo, R,
7105 TInfo, SC, isInline,
7106 HasPrototype, false);
7107 if (D.isInvalidType())
7108 NewFD->setInvalidDecl();
7113 bool isExplicit = D.getDeclSpec().isExplicitSpecified();
7114 bool isConstexpr = D.getDeclSpec().isConstexprSpecified();
7116 // Check that the return type is not an abstract class type.
7117 // For record types, this is done by the AbstractClassUsageDiagnoser once
7118 // the class has been completely parsed.
7119 if (!DC->isRecord() &&
7120 SemaRef.RequireNonAbstractType(
7121 D.getIdentifierLoc(), R->getAs<FunctionType>()->getReturnType(),
7122 diag::err_abstract_type_in_decl, SemaRef.AbstractReturnType))
7125 if (Name.getNameKind() == DeclarationName::CXXConstructorName) {
7126 // This is a C++ constructor declaration.
7127 assert(DC->isRecord() &&
7128 "Constructors can only be declared in a member context");
7130 R = SemaRef.CheckConstructorDeclarator(D, R, SC);
7131 return CXXConstructorDecl::Create(SemaRef.Context, cast<CXXRecordDecl>(DC),
7132 D.getLocStart(), NameInfo,
7133 R, TInfo, isExplicit, isInline,
7134 /*isImplicitlyDeclared=*/false,
7137 } else if (Name.getNameKind() == DeclarationName::CXXDestructorName) {
7138 // This is a C++ destructor declaration.
7139 if (DC->isRecord()) {
7140 R = SemaRef.CheckDestructorDeclarator(D, R, SC);
7141 CXXRecordDecl *Record = cast<CXXRecordDecl>(DC);
7142 CXXDestructorDecl *NewDD = CXXDestructorDecl::Create(
7143 SemaRef.Context, Record,
7145 NameInfo, R, TInfo, isInline,
7146 /*isImplicitlyDeclared=*/false);
7148 // If the class is complete, then we now create the implicit exception
7149 // specification. If the class is incomplete or dependent, we can't do
7151 if (SemaRef.getLangOpts().CPlusPlus11 && !Record->isDependentType() &&
7152 Record->getDefinition() && !Record->isBeingDefined() &&
7153 R->getAs<FunctionProtoType>()->getExceptionSpecType() == EST_None) {
7154 SemaRef.AdjustDestructorExceptionSpec(Record, NewDD);
7157 IsVirtualOkay = true;
7161 SemaRef.Diag(D.getIdentifierLoc(), diag::err_destructor_not_member);
7164 // Create a FunctionDecl to satisfy the function definition parsing
7166 return FunctionDecl::Create(SemaRef.Context, DC,
7168 D.getIdentifierLoc(), Name, R, TInfo,
7170 /*hasPrototype=*/true, isConstexpr);
7173 } else if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName) {
7174 if (!DC->isRecord()) {
7175 SemaRef.Diag(D.getIdentifierLoc(),
7176 diag::err_conv_function_not_member);
7180 SemaRef.CheckConversionDeclarator(D, R, SC);
7181 IsVirtualOkay = true;
7182 return CXXConversionDecl::Create(SemaRef.Context, cast<CXXRecordDecl>(DC),
7183 D.getLocStart(), NameInfo,
7184 R, TInfo, isInline, isExplicit,
7185 isConstexpr, SourceLocation());
7187 } else if (DC->isRecord()) {
7188 // If the name of the function is the same as the name of the record,
7189 // then this must be an invalid constructor that has a return type.
7190 // (The parser checks for a return type and makes the declarator a
7191 // constructor if it has no return type).
7192 if (Name.getAsIdentifierInfo() &&
7193 Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){
7194 SemaRef.Diag(D.getIdentifierLoc(), diag::err_constructor_return_type)
7195 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc())
7196 << SourceRange(D.getIdentifierLoc());
7200 // This is a C++ method declaration.
7201 CXXMethodDecl *Ret = CXXMethodDecl::Create(SemaRef.Context,
7202 cast<CXXRecordDecl>(DC),
7203 D.getLocStart(), NameInfo, R,
7204 TInfo, SC, isInline,
7205 isConstexpr, SourceLocation());
7206 IsVirtualOkay = !Ret->isStatic();
7210 SemaRef.getLangOpts().CPlusPlus && D.getDeclSpec().isFriendSpecified();
7211 if (!isFriend && SemaRef.CurContext->isRecord())
7214 // Determine whether the function was written with a
7215 // prototype. This true when:
7216 // - we're in C++ (where every function has a prototype),
7217 return FunctionDecl::Create(SemaRef.Context, DC,
7219 NameInfo, R, TInfo, SC, isInline,
7220 true/*HasPrototype*/, isConstexpr);
7224 enum OpenCLParamType {
7228 PrivatePtrKernelParam,
7233 static OpenCLParamType getOpenCLKernelParameterType(QualType PT) {
7234 if (PT->isPointerType()) {
7235 QualType PointeeType = PT->getPointeeType();
7236 if (PointeeType->isPointerType())
7237 return PtrPtrKernelParam;
7238 return PointeeType.getAddressSpace() == 0 ? PrivatePtrKernelParam
7242 // TODO: Forbid the other integer types (size_t, ptrdiff_t...) when they can
7243 // be used as builtin types.
7245 if (PT->isImageType())
7246 return PtrKernelParam;
7248 if (PT->isBooleanType())
7249 return InvalidKernelParam;
7252 return InvalidKernelParam;
7254 if (PT->isHalfType())
7255 return InvalidKernelParam;
7257 if (PT->isRecordType())
7258 return RecordKernelParam;
7260 return ValidKernelParam;
7263 static void checkIsValidOpenCLKernelParameter(
7267 llvm::SmallPtrSetImpl<const Type *> &ValidTypes) {
7268 QualType PT = Param->getType();
7270 // Cache the valid types we encounter to avoid rechecking structs that are
7272 if (ValidTypes.count(PT.getTypePtr()))
7275 switch (getOpenCLKernelParameterType(PT)) {
7276 case PtrPtrKernelParam:
7277 // OpenCL v1.2 s6.9.a:
7278 // A kernel function argument cannot be declared as a
7279 // pointer to a pointer type.
7280 S.Diag(Param->getLocation(), diag::err_opencl_ptrptr_kernel_param);
7284 case PrivatePtrKernelParam:
7285 // OpenCL v1.2 s6.9.a:
7286 // A kernel function argument cannot be declared as a
7287 // pointer to the private address space.
7288 S.Diag(Param->getLocation(), diag::err_opencl_private_ptr_kernel_param);
7292 // OpenCL v1.2 s6.9.k:
7293 // Arguments to kernel functions in a program cannot be declared with the
7294 // built-in scalar types bool, half, size_t, ptrdiff_t, intptr_t, and
7295 // uintptr_t or a struct and/or union that contain fields declared to be
7296 // one of these built-in scalar types.
7298 case InvalidKernelParam:
7299 // OpenCL v1.2 s6.8 n:
7300 // A kernel function argument cannot be declared
7302 S.Diag(Param->getLocation(), diag::err_bad_kernel_param_type) << PT;
7306 case PtrKernelParam:
7307 case ValidKernelParam:
7308 ValidTypes.insert(PT.getTypePtr());
7311 case RecordKernelParam:
7315 // Track nested structs we will inspect
7316 SmallVector<const Decl *, 4> VisitStack;
7318 // Track where we are in the nested structs. Items will migrate from
7319 // VisitStack to HistoryStack as we do the DFS for bad field.
7320 SmallVector<const FieldDecl *, 4> HistoryStack;
7321 HistoryStack.push_back(nullptr);
7323 const RecordDecl *PD = PT->castAs<RecordType>()->getDecl();
7324 VisitStack.push_back(PD);
7326 assert(VisitStack.back() && "First decl null?");
7329 const Decl *Next = VisitStack.pop_back_val();
7331 assert(!HistoryStack.empty());
7332 // Found a marker, we have gone up a level
7333 if (const FieldDecl *Hist = HistoryStack.pop_back_val())
7334 ValidTypes.insert(Hist->getType().getTypePtr());
7339 // Adds everything except the original parameter declaration (which is not a
7340 // field itself) to the history stack.
7341 const RecordDecl *RD;
7342 if (const FieldDecl *Field = dyn_cast<FieldDecl>(Next)) {
7343 HistoryStack.push_back(Field);
7344 RD = Field->getType()->castAs<RecordType>()->getDecl();
7346 RD = cast<RecordDecl>(Next);
7349 // Add a null marker so we know when we've gone back up a level
7350 VisitStack.push_back(nullptr);
7352 for (const auto *FD : RD->fields()) {
7353 QualType QT = FD->getType();
7355 if (ValidTypes.count(QT.getTypePtr()))
7358 OpenCLParamType ParamType = getOpenCLKernelParameterType(QT);
7359 if (ParamType == ValidKernelParam)
7362 if (ParamType == RecordKernelParam) {
7363 VisitStack.push_back(FD);
7367 // OpenCL v1.2 s6.9.p:
7368 // Arguments to kernel functions that are declared to be a struct or union
7369 // do not allow OpenCL objects to be passed as elements of the struct or
7371 if (ParamType == PtrKernelParam || ParamType == PtrPtrKernelParam ||
7372 ParamType == PrivatePtrKernelParam) {
7373 S.Diag(Param->getLocation(),
7374 diag::err_record_with_pointers_kernel_param)
7375 << PT->isUnionType()
7378 S.Diag(Param->getLocation(), diag::err_bad_kernel_param_type) << PT;
7381 S.Diag(PD->getLocation(), diag::note_within_field_of_type)
7382 << PD->getDeclName();
7384 // We have an error, now let's go back up through history and show where
7385 // the offending field came from
7386 for (ArrayRef<const FieldDecl *>::const_iterator
7387 I = HistoryStack.begin() + 1,
7388 E = HistoryStack.end();
7390 const FieldDecl *OuterField = *I;
7391 S.Diag(OuterField->getLocation(), diag::note_within_field_of_type)
7392 << OuterField->getType();
7395 S.Diag(FD->getLocation(), diag::note_illegal_field_declared_here)
7396 << QT->isPointerType()
7401 } while (!VisitStack.empty());
7405 Sema::ActOnFunctionDeclarator(Scope *S, Declarator &D, DeclContext *DC,
7406 TypeSourceInfo *TInfo, LookupResult &Previous,
7407 MultiTemplateParamsArg TemplateParamLists,
7409 QualType R = TInfo->getType();
7411 assert(R.getTypePtr()->isFunctionType());
7413 // TODO: consider using NameInfo for diagnostic.
7414 DeclarationNameInfo NameInfo = GetNameForDeclarator(D);
7415 DeclarationName Name = NameInfo.getName();
7416 StorageClass SC = getFunctionStorageClass(*this, D);
7418 if (DeclSpec::TSCS TSCS = D.getDeclSpec().getThreadStorageClassSpec())
7419 Diag(D.getDeclSpec().getThreadStorageClassSpecLoc(),
7420 diag::err_invalid_thread)
7421 << DeclSpec::getSpecifierName(TSCS);
7423 if (D.isFirstDeclarationOfMember())
7424 adjustMemberFunctionCC(R, D.isStaticMember(), D.isCtorOrDtor(),
7425 D.getIdentifierLoc());
7427 bool isFriend = false;
7428 FunctionTemplateDecl *FunctionTemplate = nullptr;
7429 bool isExplicitSpecialization = false;
7430 bool isFunctionTemplateSpecialization = false;
7432 bool isDependentClassScopeExplicitSpecialization = false;
7433 bool HasExplicitTemplateArgs = false;
7434 TemplateArgumentListInfo TemplateArgs;
7436 bool isVirtualOkay = false;
7438 DeclContext *OriginalDC = DC;
7439 bool IsLocalExternDecl = adjustContextForLocalExternDecl(DC);
7441 FunctionDecl *NewFD = CreateNewFunctionDecl(*this, D, DC, R, TInfo, SC,
7443 if (!NewFD) return nullptr;
7445 if (OriginalLexicalContext && OriginalLexicalContext->isObjCContainer())
7446 NewFD->setTopLevelDeclInObjCContainer();
7448 // Set the lexical context. If this is a function-scope declaration, or has a
7449 // C++ scope specifier, or is the object of a friend declaration, the lexical
7450 // context will be different from the semantic context.
7451 NewFD->setLexicalDeclContext(CurContext);
7453 if (IsLocalExternDecl)
7454 NewFD->setLocalExternDecl();
7456 if (getLangOpts().CPlusPlus) {
7457 bool isInline = D.getDeclSpec().isInlineSpecified();
7458 bool isVirtual = D.getDeclSpec().isVirtualSpecified();
7459 bool isExplicit = D.getDeclSpec().isExplicitSpecified();
7460 bool isConstexpr = D.getDeclSpec().isConstexprSpecified();
7461 bool isConcept = D.getDeclSpec().isConceptSpecified();
7462 isFriend = D.getDeclSpec().isFriendSpecified();
7463 if (isFriend && !isInline && D.isFunctionDefinition()) {
7464 // C++ [class.friend]p5
7465 // A function can be defined in a friend declaration of a
7466 // class . . . . Such a function is implicitly inline.
7467 NewFD->setImplicitlyInline();
7470 // If this is a method defined in an __interface, and is not a constructor
7471 // or an overloaded operator, then set the pure flag (isVirtual will already
7473 if (const CXXRecordDecl *Parent =
7474 dyn_cast<CXXRecordDecl>(NewFD->getDeclContext())) {
7475 if (Parent->isInterface() && cast<CXXMethodDecl>(NewFD)->isUserProvided())
7476 NewFD->setPure(true);
7478 // C++ [class.union]p2
7479 // A union can have member functions, but not virtual functions.
7480 if (isVirtual && Parent->isUnion())
7481 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_in_union);
7484 SetNestedNameSpecifier(NewFD, D);
7485 isExplicitSpecialization = false;
7486 isFunctionTemplateSpecialization = false;
7487 if (D.isInvalidType())
7488 NewFD->setInvalidDecl();
7490 // Match up the template parameter lists with the scope specifier, then
7491 // determine whether we have a template or a template specialization.
7492 bool Invalid = false;
7493 if (TemplateParameterList *TemplateParams =
7494 MatchTemplateParametersToScopeSpecifier(
7495 D.getDeclSpec().getLocStart(), D.getIdentifierLoc(),
7496 D.getCXXScopeSpec(),
7497 D.getName().getKind() == UnqualifiedId::IK_TemplateId
7498 ? D.getName().TemplateId
7500 TemplateParamLists, isFriend, isExplicitSpecialization,
7502 if (TemplateParams->size() > 0) {
7503 // This is a function template
7505 // Check that we can declare a template here.
7506 if (CheckTemplateDeclScope(S, TemplateParams))
7507 NewFD->setInvalidDecl();
7509 // A destructor cannot be a template.
7510 if (Name.getNameKind() == DeclarationName::CXXDestructorName) {
7511 Diag(NewFD->getLocation(), diag::err_destructor_template);
7512 NewFD->setInvalidDecl();
7515 // If we're adding a template to a dependent context, we may need to
7516 // rebuilding some of the types used within the template parameter list,
7517 // now that we know what the current instantiation is.
7518 if (DC->isDependentContext()) {
7519 ContextRAII SavedContext(*this, DC);
7520 if (RebuildTemplateParamsInCurrentInstantiation(TemplateParams))
7524 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC,
7525 NewFD->getLocation(),
7526 Name, TemplateParams,
7528 FunctionTemplate->setLexicalDeclContext(CurContext);
7529 NewFD->setDescribedFunctionTemplate(FunctionTemplate);
7531 // For source fidelity, store the other template param lists.
7532 if (TemplateParamLists.size() > 1) {
7533 NewFD->setTemplateParameterListsInfo(Context,
7534 TemplateParamLists.drop_back(1));
7537 // This is a function template specialization.
7538 isFunctionTemplateSpecialization = true;
7539 // For source fidelity, store all the template param lists.
7540 if (TemplateParamLists.size() > 0)
7541 NewFD->setTemplateParameterListsInfo(Context, TemplateParamLists);
7543 // C++0x [temp.expl.spec]p20 forbids "template<> friend void foo(int);".
7545 // We want to remove the "template<>", found here.
7546 SourceRange RemoveRange = TemplateParams->getSourceRange();
7548 // If we remove the template<> and the name is not a
7549 // template-id, we're actually silently creating a problem:
7550 // the friend declaration will refer to an untemplated decl,
7551 // and clearly the user wants a template specialization. So
7552 // we need to insert '<>' after the name.
7553 SourceLocation InsertLoc;
7554 if (D.getName().getKind() != UnqualifiedId::IK_TemplateId) {
7555 InsertLoc = D.getName().getSourceRange().getEnd();
7556 InsertLoc = getLocForEndOfToken(InsertLoc);
7559 Diag(D.getIdentifierLoc(), diag::err_template_spec_decl_friend)
7560 << Name << RemoveRange
7561 << FixItHint::CreateRemoval(RemoveRange)
7562 << FixItHint::CreateInsertion(InsertLoc, "<>");
7567 // All template param lists were matched against the scope specifier:
7568 // this is NOT (an explicit specialization of) a template.
7569 if (TemplateParamLists.size() > 0)
7570 // For source fidelity, store all the template param lists.
7571 NewFD->setTemplateParameterListsInfo(Context, TemplateParamLists);
7575 NewFD->setInvalidDecl();
7576 if (FunctionTemplate)
7577 FunctionTemplate->setInvalidDecl();
7580 // C++ [dcl.fct.spec]p5:
7581 // The virtual specifier shall only be used in declarations of
7582 // nonstatic class member functions that appear within a
7583 // member-specification of a class declaration; see 10.3.
7585 if (isVirtual && !NewFD->isInvalidDecl()) {
7586 if (!isVirtualOkay) {
7587 Diag(D.getDeclSpec().getVirtualSpecLoc(),
7588 diag::err_virtual_non_function);
7589 } else if (!CurContext->isRecord()) {
7590 // 'virtual' was specified outside of the class.
7591 Diag(D.getDeclSpec().getVirtualSpecLoc(),
7592 diag::err_virtual_out_of_class)
7593 << FixItHint::CreateRemoval(D.getDeclSpec().getVirtualSpecLoc());
7594 } else if (NewFD->getDescribedFunctionTemplate()) {
7595 // C++ [temp.mem]p3:
7596 // A member function template shall not be virtual.
7597 Diag(D.getDeclSpec().getVirtualSpecLoc(),
7598 diag::err_virtual_member_function_template)
7599 << FixItHint::CreateRemoval(D.getDeclSpec().getVirtualSpecLoc());
7601 // Okay: Add virtual to the method.
7602 NewFD->setVirtualAsWritten(true);
7605 if (getLangOpts().CPlusPlus14 &&
7606 NewFD->getReturnType()->isUndeducedType())
7607 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_auto_fn_virtual);
7610 if (getLangOpts().CPlusPlus14 &&
7611 (NewFD->isDependentContext() ||
7612 (isFriend && CurContext->isDependentContext())) &&
7613 NewFD->getReturnType()->isUndeducedType()) {
7614 // If the function template is referenced directly (for instance, as a
7615 // member of the current instantiation), pretend it has a dependent type.
7616 // This is not really justified by the standard, but is the only sane
7618 // FIXME: For a friend function, we have not marked the function as being
7619 // a friend yet, so 'isDependentContext' on the FD doesn't work.
7620 const FunctionProtoType *FPT =
7621 NewFD->getType()->castAs<FunctionProtoType>();
7623 SubstAutoType(FPT->getReturnType(), Context.DependentTy);
7624 NewFD->setType(Context.getFunctionType(Result, FPT->getParamTypes(),
7625 FPT->getExtProtoInfo()));
7628 // C++ [dcl.fct.spec]p3:
7629 // The inline specifier shall not appear on a block scope function
7631 if (isInline && !NewFD->isInvalidDecl()) {
7632 if (CurContext->isFunctionOrMethod()) {
7633 // 'inline' is not allowed on block scope function declaration.
7634 Diag(D.getDeclSpec().getInlineSpecLoc(),
7635 diag::err_inline_declaration_block_scope) << Name
7636 << FixItHint::CreateRemoval(D.getDeclSpec().getInlineSpecLoc());
7640 // C++ [dcl.fct.spec]p6:
7641 // The explicit specifier shall be used only in the declaration of a
7642 // constructor or conversion function within its class definition;
7643 // see 12.3.1 and 12.3.2.
7644 if (isExplicit && !NewFD->isInvalidDecl()) {
7645 if (!CurContext->isRecord()) {
7646 // 'explicit' was specified outside of the class.
7647 Diag(D.getDeclSpec().getExplicitSpecLoc(),
7648 diag::err_explicit_out_of_class)
7649 << FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecLoc());
7650 } else if (!isa<CXXConstructorDecl>(NewFD) &&
7651 !isa<CXXConversionDecl>(NewFD)) {
7652 // 'explicit' was specified on a function that wasn't a constructor
7653 // or conversion function.
7654 Diag(D.getDeclSpec().getExplicitSpecLoc(),
7655 diag::err_explicit_non_ctor_or_conv_function)
7656 << FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecLoc());
7661 // C++11 [dcl.constexpr]p2: constexpr functions and constexpr constructors
7662 // are implicitly inline.
7663 NewFD->setImplicitlyInline();
7665 // C++11 [dcl.constexpr]p3: functions declared constexpr are required to
7666 // be either constructors or to return a literal type. Therefore,
7667 // destructors cannot be declared constexpr.
7668 if (isa<CXXDestructorDecl>(NewFD))
7669 Diag(D.getDeclSpec().getConstexprSpecLoc(), diag::err_constexpr_dtor);
7673 // This is a function concept.
7674 if (FunctionTemplateDecl *FTD = NewFD->getDescribedFunctionTemplate())
7677 // C++ Concepts TS [dcl.spec.concept]p1: The concept specifier shall be
7678 // applied only to the definition of a function template [...]
7679 if (!D.isFunctionDefinition()) {
7680 Diag(D.getDeclSpec().getConceptSpecLoc(),
7681 diag::err_function_concept_not_defined);
7682 NewFD->setInvalidDecl();
7685 // C++ Concepts TS [dcl.spec.concept]p1: [...] A function concept shall
7686 // have no exception-specification and is treated as if it were specified
7687 // with noexcept(true) (15.4). [...]
7688 if (const FunctionProtoType *FPT = R->getAs<FunctionProtoType>()) {
7689 if (FPT->hasExceptionSpec()) {
7691 if (D.isFunctionDeclarator())
7692 Range = D.getFunctionTypeInfo().getExceptionSpecRange();
7693 Diag(NewFD->getLocation(), diag::err_function_concept_exception_spec)
7694 << FixItHint::CreateRemoval(Range);
7695 NewFD->setInvalidDecl();
7697 Context.adjustExceptionSpec(NewFD, EST_BasicNoexcept);
7700 // C++ Concepts TS [dcl.spec.concept]p5: A function concept has the
7701 // following restrictions:
7702 // - The declared return type shall have the type bool.
7703 if (!Context.hasSameType(FPT->getReturnType(), Context.BoolTy)) {
7704 Diag(D.getIdentifierLoc(), diag::err_function_concept_bool_ret);
7705 NewFD->setInvalidDecl();
7708 // C++ Concepts TS [dcl.spec.concept]p5: A function concept has the
7709 // following restrictions:
7710 // - The declaration's parameter list shall be equivalent to an empty
7712 if (FPT->getNumParams() > 0 || FPT->isVariadic())
7713 Diag(NewFD->getLocation(), diag::err_function_concept_with_params);
7716 // C++ Concepts TS [dcl.spec.concept]p2: Every concept definition is
7717 // implicity defined to be a constexpr declaration (implicitly inline)
7718 NewFD->setImplicitlyInline();
7720 // C++ Concepts TS [dcl.spec.concept]p2: A concept definition shall not
7721 // be declared with the thread_local, inline, friend, or constexpr
7722 // specifiers, [...]
7724 Diag(D.getDeclSpec().getInlineSpecLoc(),
7725 diag::err_concept_decl_invalid_specifiers)
7727 NewFD->setInvalidDecl(true);
7731 Diag(D.getDeclSpec().getFriendSpecLoc(),
7732 diag::err_concept_decl_invalid_specifiers)
7734 NewFD->setInvalidDecl(true);
7738 Diag(D.getDeclSpec().getConstexprSpecLoc(),
7739 diag::err_concept_decl_invalid_specifiers)
7741 NewFD->setInvalidDecl(true);
7744 // C++ Concepts TS [dcl.spec.concept]p1: The concept specifier shall be
7745 // applied only to the definition of a function template or variable
7746 // template, declared in namespace scope.
7747 if (isFunctionTemplateSpecialization) {
7748 Diag(D.getDeclSpec().getConceptSpecLoc(),
7749 diag::err_concept_specified_specialization) << 1;
7753 // If __module_private__ was specified, mark the function accordingly.
7754 if (D.getDeclSpec().isModulePrivateSpecified()) {
7755 if (isFunctionTemplateSpecialization) {
7756 SourceLocation ModulePrivateLoc
7757 = D.getDeclSpec().getModulePrivateSpecLoc();
7758 Diag(ModulePrivateLoc, diag::err_module_private_specialization)
7760 << FixItHint::CreateRemoval(ModulePrivateLoc);
7762 NewFD->setModulePrivate();
7763 if (FunctionTemplate)
7764 FunctionTemplate->setModulePrivate();
7769 if (FunctionTemplate) {
7770 FunctionTemplate->setObjectOfFriendDecl();
7771 FunctionTemplate->setAccess(AS_public);
7773 NewFD->setObjectOfFriendDecl();
7774 NewFD->setAccess(AS_public);
7777 // If a function is defined as defaulted or deleted, mark it as such now.
7778 // FIXME: Does this ever happen? ActOnStartOfFunctionDef forces the function
7779 // definition kind to FDK_Definition.
7780 switch (D.getFunctionDefinitionKind()) {
7781 case FDK_Declaration:
7782 case FDK_Definition:
7786 NewFD->setDefaulted();
7790 NewFD->setDeletedAsWritten();
7794 if (isa<CXXMethodDecl>(NewFD) && DC == CurContext &&
7795 D.isFunctionDefinition()) {
7796 // C++ [class.mfct]p2:
7797 // A member function may be defined (8.4) in its class definition, in
7798 // which case it is an inline member function (7.1.2)
7799 NewFD->setImplicitlyInline();
7802 if (SC == SC_Static && isa<CXXMethodDecl>(NewFD) &&
7803 !CurContext->isRecord()) {
7804 // C++ [class.static]p1:
7805 // A data or function member of a class may be declared static
7806 // in a class definition, in which case it is a static member of
7809 // Complain about the 'static' specifier if it's on an out-of-line
7810 // member function definition.
7811 Diag(D.getDeclSpec().getStorageClassSpecLoc(),
7812 diag::err_static_out_of_line)
7813 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc());
7816 // C++11 [except.spec]p15:
7817 // A deallocation function with no exception-specification is treated
7818 // as if it were specified with noexcept(true).
7819 const FunctionProtoType *FPT = R->getAs<FunctionProtoType>();
7820 if ((Name.getCXXOverloadedOperator() == OO_Delete ||
7821 Name.getCXXOverloadedOperator() == OO_Array_Delete) &&
7822 getLangOpts().CPlusPlus11 && FPT && !FPT->hasExceptionSpec())
7823 NewFD->setType(Context.getFunctionType(
7824 FPT->getReturnType(), FPT->getParamTypes(),
7825 FPT->getExtProtoInfo().withExceptionSpec(EST_BasicNoexcept)));
7828 // Filter out previous declarations that don't match the scope.
7829 FilterLookupForScope(Previous, OriginalDC, S, shouldConsiderLinkage(NewFD),
7830 D.getCXXScopeSpec().isNotEmpty() ||
7831 isExplicitSpecialization ||
7832 isFunctionTemplateSpecialization);
7834 // Handle GNU asm-label extension (encoded as an attribute).
7835 if (Expr *E = (Expr*) D.getAsmLabel()) {
7836 // The parser guarantees this is a string.
7837 StringLiteral *SE = cast<StringLiteral>(E);
7838 NewFD->addAttr(::new (Context) AsmLabelAttr(SE->getStrTokenLoc(0), Context,
7839 SE->getString(), 0));
7840 } else if (!ExtnameUndeclaredIdentifiers.empty()) {
7841 llvm::DenseMap<IdentifierInfo*,AsmLabelAttr*>::iterator I =
7842 ExtnameUndeclaredIdentifiers.find(NewFD->getIdentifier());
7843 if (I != ExtnameUndeclaredIdentifiers.end()) {
7844 if (isDeclExternC(NewFD)) {
7845 NewFD->addAttr(I->second);
7846 ExtnameUndeclaredIdentifiers.erase(I);
7848 Diag(NewFD->getLocation(), diag::warn_redefine_extname_not_applied)
7849 << /*Variable*/0 << NewFD;
7853 // Copy the parameter declarations from the declarator D to the function
7854 // declaration NewFD, if they are available. First scavenge them into Params.
7855 SmallVector<ParmVarDecl*, 16> Params;
7856 if (D.isFunctionDeclarator()) {
7857 DeclaratorChunk::FunctionTypeInfo &FTI = D.getFunctionTypeInfo();
7859 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs
7860 // function that takes no arguments, not a function that takes a
7861 // single void argument.
7862 // We let through "const void" here because Sema::GetTypeForDeclarator
7863 // already checks for that case.
7864 if (FTIHasNonVoidParameters(FTI) && FTI.Params[0].Param) {
7865 for (unsigned i = 0, e = FTI.NumParams; i != e; ++i) {
7866 ParmVarDecl *Param = cast<ParmVarDecl>(FTI.Params[i].Param);
7867 assert(Param->getDeclContext() != NewFD && "Was set before ?");
7868 Param->setDeclContext(NewFD);
7869 Params.push_back(Param);
7871 if (Param->isInvalidDecl())
7872 NewFD->setInvalidDecl();
7875 } else if (const FunctionProtoType *FT = R->getAs<FunctionProtoType>()) {
7876 // When we're declaring a function with a typedef, typeof, etc as in the
7877 // following example, we'll need to synthesize (unnamed)
7878 // parameters for use in the declaration.
7881 // typedef void fn(int);
7885 // Synthesize a parameter for each argument type.
7886 for (const auto &AI : FT->param_types()) {
7887 ParmVarDecl *Param =
7888 BuildParmVarDeclForTypedef(NewFD, D.getIdentifierLoc(), AI);
7889 Param->setScopeInfo(0, Params.size());
7890 Params.push_back(Param);
7893 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 &&
7894 "Should not need args for typedef of non-prototype fn");
7897 // Finally, we know we have the right number of parameters, install them.
7898 NewFD->setParams(Params);
7900 // Find all anonymous symbols defined during the declaration of this function
7901 // and add to NewFD. This lets us track decls such 'enum Y' in:
7903 // void f(enum Y {AA} x) {}
7905 // which would otherwise incorrectly end up in the translation unit scope.
7906 NewFD->setDeclsInPrototypeScope(DeclsInPrototypeScope);
7907 DeclsInPrototypeScope.clear();
7909 if (D.getDeclSpec().isNoreturnSpecified())
7911 ::new(Context) C11NoReturnAttr(D.getDeclSpec().getNoreturnSpecLoc(),
7914 // Functions returning a variably modified type violate C99 6.7.5.2p2
7915 // because all functions have linkage.
7916 if (!NewFD->isInvalidDecl() &&
7917 NewFD->getReturnType()->isVariablyModifiedType()) {
7918 Diag(NewFD->getLocation(), diag::err_vm_func_decl);
7919 NewFD->setInvalidDecl();
7922 // Apply an implicit SectionAttr if #pragma code_seg is active.
7923 if (CodeSegStack.CurrentValue && D.isFunctionDefinition() &&
7924 !NewFD->hasAttr<SectionAttr>()) {
7926 SectionAttr::CreateImplicit(Context, SectionAttr::Declspec_allocate,
7927 CodeSegStack.CurrentValue->getString(),
7928 CodeSegStack.CurrentPragmaLocation));
7929 if (UnifySection(CodeSegStack.CurrentValue->getString(),
7930 ASTContext::PSF_Implicit | ASTContext::PSF_Execute |
7931 ASTContext::PSF_Read,
7933 NewFD->dropAttr<SectionAttr>();
7936 // Handle attributes.
7937 ProcessDeclAttributes(S, NewFD, D);
7939 if (getLangOpts().OpenCL) {
7940 // OpenCL v1.1 s6.5: Using an address space qualifier in a function return
7941 // type declaration will generate a compilation error.
7942 unsigned AddressSpace = NewFD->getReturnType().getAddressSpace();
7943 if (AddressSpace == LangAS::opencl_local ||
7944 AddressSpace == LangAS::opencl_global ||
7945 AddressSpace == LangAS::opencl_constant) {
7946 Diag(NewFD->getLocation(),
7947 diag::err_opencl_return_value_with_address_space);
7948 NewFD->setInvalidDecl();
7952 if (!getLangOpts().CPlusPlus) {
7953 // Perform semantic checking on the function declaration.
7954 bool isExplicitSpecialization=false;
7955 if (!NewFD->isInvalidDecl() && NewFD->isMain())
7956 CheckMain(NewFD, D.getDeclSpec());
7958 if (!NewFD->isInvalidDecl() && NewFD->isMSVCRTEntryPoint())
7959 CheckMSVCRTEntryPoint(NewFD);
7961 if (!NewFD->isInvalidDecl())
7962 D.setRedeclaration(CheckFunctionDeclaration(S, NewFD, Previous,
7963 isExplicitSpecialization));
7964 else if (!Previous.empty())
7965 // Recover gracefully from an invalid redeclaration.
7966 D.setRedeclaration(true);
7967 assert((NewFD->isInvalidDecl() || !D.isRedeclaration() ||
7968 Previous.getResultKind() != LookupResult::FoundOverloaded) &&
7969 "previous declaration set still overloaded");
7971 // Diagnose no-prototype function declarations with calling conventions that
7972 // don't support variadic calls. Only do this in C and do it after merging
7973 // possibly prototyped redeclarations.
7974 const FunctionType *FT = NewFD->getType()->castAs<FunctionType>();
7975 if (isa<FunctionNoProtoType>(FT) && !D.isFunctionDefinition()) {
7976 CallingConv CC = FT->getExtInfo().getCC();
7977 if (!supportsVariadicCall(CC)) {
7978 // Windows system headers sometimes accidentally use stdcall without
7979 // (void) parameters, so we relax this to a warning.
7981 CC == CC_X86StdCall ? diag::warn_cconv_knr : diag::err_cconv_knr;
7982 Diag(NewFD->getLocation(), DiagID)
7983 << FunctionType::getNameForCallConv(CC);
7987 // C++11 [replacement.functions]p3:
7988 // The program's definitions shall not be specified as inline.
7990 // N.B. We diagnose declarations instead of definitions per LWG issue 2340.
7992 // Suppress the diagnostic if the function is __attribute__((used)), since
7993 // that forces an external definition to be emitted.
7994 if (D.getDeclSpec().isInlineSpecified() &&
7995 NewFD->isReplaceableGlobalAllocationFunction() &&
7996 !NewFD->hasAttr<UsedAttr>())
7997 Diag(D.getDeclSpec().getInlineSpecLoc(),
7998 diag::ext_operator_new_delete_declared_inline)
7999 << NewFD->getDeclName();
8001 // If the declarator is a template-id, translate the parser's template
8002 // argument list into our AST format.
8003 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) {
8004 TemplateIdAnnotation *TemplateId = D.getName().TemplateId;
8005 TemplateArgs.setLAngleLoc(TemplateId->LAngleLoc);
8006 TemplateArgs.setRAngleLoc(TemplateId->RAngleLoc);
8007 ASTTemplateArgsPtr TemplateArgsPtr(TemplateId->getTemplateArgs(),
8008 TemplateId->NumArgs);
8009 translateTemplateArguments(TemplateArgsPtr,
8012 HasExplicitTemplateArgs = true;
8014 if (NewFD->isInvalidDecl()) {
8015 HasExplicitTemplateArgs = false;
8016 } else if (FunctionTemplate) {
8017 // Function template with explicit template arguments.
8018 Diag(D.getIdentifierLoc(), diag::err_function_template_partial_spec)
8019 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc);
8021 HasExplicitTemplateArgs = false;
8023 assert((isFunctionTemplateSpecialization ||
8024 D.getDeclSpec().isFriendSpecified()) &&
8025 "should have a 'template<>' for this decl");
8026 // "friend void foo<>(int);" is an implicit specialization decl.
8027 isFunctionTemplateSpecialization = true;
8029 } else if (isFriend && isFunctionTemplateSpecialization) {
8030 // This combination is only possible in a recovery case; the user
8031 // wrote something like:
8032 // template <> friend void foo(int);
8033 // which we're recovering from as if the user had written:
8034 // friend void foo<>(int);
8035 // Go ahead and fake up a template id.
8036 HasExplicitTemplateArgs = true;
8037 TemplateArgs.setLAngleLoc(D.getIdentifierLoc());
8038 TemplateArgs.setRAngleLoc(D.getIdentifierLoc());
8041 // If it's a friend (and only if it's a friend), it's possible
8042 // that either the specialized function type or the specialized
8043 // template is dependent, and therefore matching will fail. In
8044 // this case, don't check the specialization yet.
8045 bool InstantiationDependent = false;
8046 if (isFunctionTemplateSpecialization && isFriend &&
8047 (NewFD->getType()->isDependentType() || DC->isDependentContext() ||
8048 TemplateSpecializationType::anyDependentTemplateArguments(
8049 TemplateArgs.getArgumentArray(), TemplateArgs.size(),
8050 InstantiationDependent))) {
8051 assert(HasExplicitTemplateArgs &&
8052 "friend function specialization without template args");
8053 if (CheckDependentFunctionTemplateSpecialization(NewFD, TemplateArgs,
8055 NewFD->setInvalidDecl();
8056 } else if (isFunctionTemplateSpecialization) {
8057 if (CurContext->isDependentContext() && CurContext->isRecord()
8059 isDependentClassScopeExplicitSpecialization = true;
8060 Diag(NewFD->getLocation(), getLangOpts().MicrosoftExt ?
8061 diag::ext_function_specialization_in_class :
8062 diag::err_function_specialization_in_class)
8063 << NewFD->getDeclName();
8064 } else if (CheckFunctionTemplateSpecialization(NewFD,
8065 (HasExplicitTemplateArgs ? &TemplateArgs
8068 NewFD->setInvalidDecl();
8071 // A storage-class-specifier shall not be specified in an explicit
8072 // specialization (14.7.3)
8073 FunctionTemplateSpecializationInfo *Info =
8074 NewFD->getTemplateSpecializationInfo();
8075 if (Info && SC != SC_None) {
8076 if (SC != Info->getTemplate()->getTemplatedDecl()->getStorageClass())
8077 Diag(NewFD->getLocation(),
8078 diag::err_explicit_specialization_inconsistent_storage_class)
8080 << FixItHint::CreateRemoval(
8081 D.getDeclSpec().getStorageClassSpecLoc());
8084 Diag(NewFD->getLocation(),
8085 diag::ext_explicit_specialization_storage_class)
8086 << FixItHint::CreateRemoval(
8087 D.getDeclSpec().getStorageClassSpecLoc());
8089 } else if (isExplicitSpecialization && isa<CXXMethodDecl>(NewFD)) {
8090 if (CheckMemberSpecialization(NewFD, Previous))
8091 NewFD->setInvalidDecl();
8094 // Perform semantic checking on the function declaration.
8095 if (!isDependentClassScopeExplicitSpecialization) {
8096 if (!NewFD->isInvalidDecl() && NewFD->isMain())
8097 CheckMain(NewFD, D.getDeclSpec());
8099 if (!NewFD->isInvalidDecl() && NewFD->isMSVCRTEntryPoint())
8100 CheckMSVCRTEntryPoint(NewFD);
8102 if (!NewFD->isInvalidDecl())
8103 D.setRedeclaration(CheckFunctionDeclaration(S, NewFD, Previous,
8104 isExplicitSpecialization));
8105 else if (!Previous.empty())
8106 // Recover gracefully from an invalid redeclaration.
8107 D.setRedeclaration(true);
8110 assert((NewFD->isInvalidDecl() || !D.isRedeclaration() ||
8111 Previous.getResultKind() != LookupResult::FoundOverloaded) &&
8112 "previous declaration set still overloaded");
8114 NamedDecl *PrincipalDecl = (FunctionTemplate
8115 ? cast<NamedDecl>(FunctionTemplate)
8118 if (isFriend && D.isRedeclaration()) {
8119 AccessSpecifier Access = AS_public;
8120 if (!NewFD->isInvalidDecl())
8121 Access = NewFD->getPreviousDecl()->getAccess();
8123 NewFD->setAccess(Access);
8124 if (FunctionTemplate) FunctionTemplate->setAccess(Access);
8127 if (NewFD->isOverloadedOperator() && !DC->isRecord() &&
8128 PrincipalDecl->isInIdentifierNamespace(Decl::IDNS_Ordinary))
8129 PrincipalDecl->setNonMemberOperator();
8131 // If we have a function template, check the template parameter
8132 // list. This will check and merge default template arguments.
8133 if (FunctionTemplate) {
8134 FunctionTemplateDecl *PrevTemplate =
8135 FunctionTemplate->getPreviousDecl();
8136 CheckTemplateParameterList(FunctionTemplate->getTemplateParameters(),
8137 PrevTemplate ? PrevTemplate->getTemplateParameters()
8139 D.getDeclSpec().isFriendSpecified()
8140 ? (D.isFunctionDefinition()
8141 ? TPC_FriendFunctionTemplateDefinition
8142 : TPC_FriendFunctionTemplate)
8143 : (D.getCXXScopeSpec().isSet() &&
8144 DC && DC->isRecord() &&
8145 DC->isDependentContext())
8146 ? TPC_ClassTemplateMember
8147 : TPC_FunctionTemplate);
8150 if (NewFD->isInvalidDecl()) {
8151 // Ignore all the rest of this.
8152 } else if (!D.isRedeclaration()) {
8153 struct ActOnFDArgs ExtraArgs = { S, D, TemplateParamLists,
8155 // Fake up an access specifier if it's supposed to be a class member.
8156 if (isa<CXXRecordDecl>(NewFD->getDeclContext()))
8157 NewFD->setAccess(AS_public);
8159 // Qualified decls generally require a previous declaration.
8160 if (D.getCXXScopeSpec().isSet()) {
8161 // ...with the major exception of templated-scope or
8162 // dependent-scope friend declarations.
8164 // TODO: we currently also suppress this check in dependent
8165 // contexts because (1) the parameter depth will be off when
8166 // matching friend templates and (2) we might actually be
8167 // selecting a friend based on a dependent factor. But there
8168 // are situations where these conditions don't apply and we
8169 // can actually do this check immediately.
8171 (TemplateParamLists.size() ||
8172 D.getCXXScopeSpec().getScopeRep()->isDependent() ||
8173 CurContext->isDependentContext())) {
8176 // The user tried to provide an out-of-line definition for a
8177 // function that is a member of a class or namespace, but there
8178 // was no such member function declared (C++ [class.mfct]p2,
8179 // C++ [namespace.memdef]p2). For example:
8185 // void X::f() { } // ill-formed
8187 // Complain about this problem, and attempt to suggest close
8188 // matches (e.g., those that differ only in cv-qualifiers and
8189 // whether the parameter types are references).
8191 if (NamedDecl *Result = DiagnoseInvalidRedeclaration(
8192 *this, Previous, NewFD, ExtraArgs, false, nullptr)) {
8193 AddToScope = ExtraArgs.AddToScope;
8198 // Unqualified local friend declarations are required to resolve
8200 } else if (isFriend && cast<CXXRecordDecl>(CurContext)->isLocalClass()) {
8201 if (NamedDecl *Result = DiagnoseInvalidRedeclaration(
8202 *this, Previous, NewFD, ExtraArgs, true, S)) {
8203 AddToScope = ExtraArgs.AddToScope;
8207 } else if (!D.isFunctionDefinition() &&
8208 isa<CXXMethodDecl>(NewFD) && NewFD->isOutOfLine() &&
8209 !isFriend && !isFunctionTemplateSpecialization &&
8210 !isExplicitSpecialization) {
8211 // An out-of-line member function declaration must also be a
8212 // definition (C++ [class.mfct]p2).
8213 // Note that this is not the case for explicit specializations of
8214 // function templates or member functions of class templates, per
8215 // C++ [temp.expl.spec]p2. We also allow these declarations as an
8216 // extension for compatibility with old SWIG code which likes to
8218 Diag(NewFD->getLocation(), diag::ext_out_of_line_declaration)
8219 << D.getCXXScopeSpec().getRange();
8223 ProcessPragmaWeak(S, NewFD);
8224 checkAttributesAfterMerging(*this, *NewFD);
8226 AddKnownFunctionAttributes(NewFD);
8228 if (NewFD->hasAttr<OverloadableAttr>() &&
8229 !NewFD->getType()->getAs<FunctionProtoType>()) {
8230 Diag(NewFD->getLocation(),
8231 diag::err_attribute_overloadable_no_prototype)
8234 // Turn this into a variadic function with no parameters.
8235 const FunctionType *FT = NewFD->getType()->getAs<FunctionType>();
8236 FunctionProtoType::ExtProtoInfo EPI(
8237 Context.getDefaultCallingConvention(true, false));
8238 EPI.Variadic = true;
8239 EPI.ExtInfo = FT->getExtInfo();
8241 QualType R = Context.getFunctionType(FT->getReturnType(), None, EPI);
8245 // If there's a #pragma GCC visibility in scope, and this isn't a class
8246 // member, set the visibility of this function.
8247 if (!DC->isRecord() && NewFD->isExternallyVisible())
8248 AddPushedVisibilityAttribute(NewFD);
8250 // If there's a #pragma clang arc_cf_code_audited in scope, consider
8251 // marking the function.
8252 AddCFAuditedAttribute(NewFD);
8254 // If this is a function definition, check if we have to apply optnone due to
8256 if(D.isFunctionDefinition())
8257 AddRangeBasedOptnone(NewFD);
8259 // If this is the first declaration of an extern C variable, update
8260 // the map of such variables.
8261 if (NewFD->isFirstDecl() && !NewFD->isInvalidDecl() &&
8262 isIncompleteDeclExternC(*this, NewFD))
8263 RegisterLocallyScopedExternCDecl(NewFD, S);
8265 // Set this FunctionDecl's range up to the right paren.
8266 NewFD->setRangeEnd(D.getSourceRange().getEnd());
8268 if (D.isRedeclaration() && !Previous.empty()) {
8269 checkDLLAttributeRedeclaration(
8270 *this, dyn_cast<NamedDecl>(Previous.getRepresentativeDecl()), NewFD,
8271 isExplicitSpecialization || isFunctionTemplateSpecialization);
8274 if (getLangOpts().CPlusPlus) {
8275 if (FunctionTemplate) {
8276 if (NewFD->isInvalidDecl())
8277 FunctionTemplate->setInvalidDecl();
8278 return FunctionTemplate;
8282 if (NewFD->hasAttr<OpenCLKernelAttr>()) {
8283 // OpenCL v1.2 s6.8 static is invalid for kernel functions.
8284 if ((getLangOpts().OpenCLVersion >= 120)
8285 && (SC == SC_Static)) {
8286 Diag(D.getIdentifierLoc(), diag::err_static_kernel);
8290 // OpenCL v1.2, s6.9 -- Kernels can only have return type void.
8291 if (!NewFD->getReturnType()->isVoidType()) {
8292 SourceRange RTRange = NewFD->getReturnTypeSourceRange();
8293 Diag(D.getIdentifierLoc(), diag::err_expected_kernel_void_return_type)
8294 << (RTRange.isValid() ? FixItHint::CreateReplacement(RTRange, "void")
8299 llvm::SmallPtrSet<const Type *, 16> ValidTypes;
8300 for (auto Param : NewFD->params())
8301 checkIsValidOpenCLKernelParameter(*this, D, Param, ValidTypes);
8303 for (FunctionDecl::param_iterator PI = NewFD->param_begin(),
8304 PE = NewFD->param_end(); PI != PE; ++PI) {
8305 ParmVarDecl *Param = *PI;
8306 QualType PT = Param->getType();
8308 // OpenCL 2.0 pipe restrictions forbids pipe packet types to be non-value
8310 if (getLangOpts().OpenCLVersion >= 200) {
8311 if(const PipeType *PipeTy = PT->getAs<PipeType>()) {
8312 QualType ElemTy = PipeTy->getElementType();
8313 if (ElemTy->isReferenceType() || ElemTy->isPointerType()) {
8314 Diag(Param->getTypeSpecStartLoc(), diag::err_reference_pipe_type );
8321 MarkUnusedFileScopedDecl(NewFD);
8323 if (getLangOpts().CUDA) {
8324 IdentifierInfo *II = NewFD->getIdentifier();
8325 if (II && II->isStr("cudaConfigureCall") && !NewFD->isInvalidDecl() &&
8326 NewFD->getDeclContext()->getRedeclContext()->isTranslationUnit()) {
8327 if (!R->getAs<FunctionType>()->getReturnType()->isScalarType())
8328 Diag(NewFD->getLocation(), diag::err_config_scalar_return);
8330 Context.setcudaConfigureCallDecl(NewFD);
8333 // Variadic functions, other than a *declaration* of printf, are not allowed
8334 // in device-side CUDA code, unless someone passed
8335 // -fcuda-allow-variadic-functions.
8336 if (!getLangOpts().CUDAAllowVariadicFunctions && NewFD->isVariadic() &&
8337 (NewFD->hasAttr<CUDADeviceAttr>() ||
8338 NewFD->hasAttr<CUDAGlobalAttr>()) &&
8339 !(II && II->isStr("printf") && NewFD->isExternC() &&
8340 !D.isFunctionDefinition())) {
8341 Diag(NewFD->getLocation(), diag::err_variadic_device_fn);
8345 // Here we have an function template explicit specialization at class scope.
8346 // The actually specialization will be postponed to template instatiation
8347 // time via the ClassScopeFunctionSpecializationDecl node.
8348 if (isDependentClassScopeExplicitSpecialization) {
8349 ClassScopeFunctionSpecializationDecl *NewSpec =
8350 ClassScopeFunctionSpecializationDecl::Create(
8351 Context, CurContext, SourceLocation(),
8352 cast<CXXMethodDecl>(NewFD),
8353 HasExplicitTemplateArgs, TemplateArgs);
8354 CurContext->addDecl(NewSpec);
8361 /// \brief Perform semantic checking of a new function declaration.
8363 /// Performs semantic analysis of the new function declaration
8364 /// NewFD. This routine performs all semantic checking that does not
8365 /// require the actual declarator involved in the declaration, and is
8366 /// used both for the declaration of functions as they are parsed
8367 /// (called via ActOnDeclarator) and for the declaration of functions
8368 /// that have been instantiated via C++ template instantiation (called
8369 /// via InstantiateDecl).
8371 /// \param IsExplicitSpecialization whether this new function declaration is
8372 /// an explicit specialization of the previous declaration.
8374 /// This sets NewFD->isInvalidDecl() to true if there was an error.
8376 /// \returns true if the function declaration is a redeclaration.
8377 bool Sema::CheckFunctionDeclaration(Scope *S, FunctionDecl *NewFD,
8378 LookupResult &Previous,
8379 bool IsExplicitSpecialization) {
8380 assert(!NewFD->getReturnType()->isVariablyModifiedType() &&
8381 "Variably modified return types are not handled here");
8383 // Determine whether the type of this function should be merged with
8384 // a previous visible declaration. This never happens for functions in C++,
8385 // and always happens in C if the previous declaration was visible.
8386 bool MergeTypeWithPrevious = !getLangOpts().CPlusPlus &&
8387 !Previous.isShadowed();
8389 bool Redeclaration = false;
8390 NamedDecl *OldDecl = nullptr;
8392 // Merge or overload the declaration with an existing declaration of
8393 // the same name, if appropriate.
8394 if (!Previous.empty()) {
8395 // Determine whether NewFD is an overload of PrevDecl or
8396 // a declaration that requires merging. If it's an overload,
8397 // there's no more work to do here; we'll just add the new
8398 // function to the scope.
8399 if (!AllowOverloadingOfFunction(Previous, Context)) {
8400 NamedDecl *Candidate = Previous.getRepresentativeDecl();
8401 if (shouldLinkPossiblyHiddenDecl(Candidate, NewFD)) {
8402 Redeclaration = true;
8403 OldDecl = Candidate;
8406 switch (CheckOverload(S, NewFD, Previous, OldDecl,
8407 /*NewIsUsingDecl*/ false)) {
8409 Redeclaration = true;
8412 case Ovl_NonFunction:
8413 Redeclaration = true;
8417 Redeclaration = false;
8421 if (!getLangOpts().CPlusPlus && !NewFD->hasAttr<OverloadableAttr>()) {
8422 // If a function name is overloadable in C, then every function
8423 // with that name must be marked "overloadable".
8424 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing)
8425 << Redeclaration << NewFD;
8426 NamedDecl *OverloadedDecl = nullptr;
8428 OverloadedDecl = OldDecl;
8429 else if (!Previous.empty())
8430 OverloadedDecl = Previous.getRepresentativeDecl();
8432 Diag(OverloadedDecl->getLocation(),
8433 diag::note_attribute_overloadable_prev_overload);
8434 NewFD->addAttr(OverloadableAttr::CreateImplicit(Context));
8439 // Check for a previous extern "C" declaration with this name.
8440 if (!Redeclaration &&
8441 checkForConflictWithNonVisibleExternC(*this, NewFD, Previous)) {
8442 if (!Previous.empty()) {
8443 // This is an extern "C" declaration with the same name as a previous
8444 // declaration, and thus redeclares that entity...
8445 Redeclaration = true;
8446 OldDecl = Previous.getFoundDecl();
8447 MergeTypeWithPrevious = false;
8449 // ... except in the presence of __attribute__((overloadable)).
8450 if (OldDecl->hasAttr<OverloadableAttr>()) {
8451 if (!getLangOpts().CPlusPlus && !NewFD->hasAttr<OverloadableAttr>()) {
8452 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing)
8453 << Redeclaration << NewFD;
8454 Diag(Previous.getFoundDecl()->getLocation(),
8455 diag::note_attribute_overloadable_prev_overload);
8456 NewFD->addAttr(OverloadableAttr::CreateImplicit(Context));
8458 if (IsOverload(NewFD, cast<FunctionDecl>(OldDecl), false)) {
8459 Redeclaration = false;
8466 // C++11 [dcl.constexpr]p8:
8467 // A constexpr specifier for a non-static member function that is not
8468 // a constructor declares that member function to be const.
8470 // This needs to be delayed until we know whether this is an out-of-line
8471 // definition of a static member function.
8473 // This rule is not present in C++1y, so we produce a backwards
8474 // compatibility warning whenever it happens in C++11.
8475 CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(NewFD);
8476 if (!getLangOpts().CPlusPlus14 && MD && MD->isConstexpr() &&
8477 !MD->isStatic() && !isa<CXXConstructorDecl>(MD) &&
8478 (MD->getTypeQualifiers() & Qualifiers::Const) == 0) {
8479 CXXMethodDecl *OldMD = nullptr;
8481 OldMD = dyn_cast_or_null<CXXMethodDecl>(OldDecl->getAsFunction());
8482 if (!OldMD || !OldMD->isStatic()) {
8483 const FunctionProtoType *FPT =
8484 MD->getType()->castAs<FunctionProtoType>();
8485 FunctionProtoType::ExtProtoInfo EPI = FPT->getExtProtoInfo();
8486 EPI.TypeQuals |= Qualifiers::Const;
8487 MD->setType(Context.getFunctionType(FPT->getReturnType(),
8488 FPT->getParamTypes(), EPI));
8490 // Warn that we did this, if we're not performing template instantiation.
8491 // In that case, we'll have warned already when the template was defined.
8492 if (ActiveTemplateInstantiations.empty()) {
8493 SourceLocation AddConstLoc;
8494 if (FunctionTypeLoc FTL = MD->getTypeSourceInfo()->getTypeLoc()
8495 .IgnoreParens().getAs<FunctionTypeLoc>())
8496 AddConstLoc = getLocForEndOfToken(FTL.getRParenLoc());
8498 Diag(MD->getLocation(), diag::warn_cxx14_compat_constexpr_not_const)
8499 << FixItHint::CreateInsertion(AddConstLoc, " const");
8504 if (Redeclaration) {
8505 // NewFD and OldDecl represent declarations that need to be
8507 if (MergeFunctionDecl(NewFD, OldDecl, S, MergeTypeWithPrevious)) {
8508 NewFD->setInvalidDecl();
8509 return Redeclaration;
8513 Previous.addDecl(OldDecl);
8515 if (FunctionTemplateDecl *OldTemplateDecl
8516 = dyn_cast<FunctionTemplateDecl>(OldDecl)) {
8517 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl());
8518 FunctionTemplateDecl *NewTemplateDecl
8519 = NewFD->getDescribedFunctionTemplate();
8520 assert(NewTemplateDecl && "Template/non-template mismatch");
8521 if (CXXMethodDecl *Method
8522 = dyn_cast<CXXMethodDecl>(NewTemplateDecl->getTemplatedDecl())) {
8523 Method->setAccess(OldTemplateDecl->getAccess());
8524 NewTemplateDecl->setAccess(OldTemplateDecl->getAccess());
8527 // If this is an explicit specialization of a member that is a function
8528 // template, mark it as a member specialization.
8529 if (IsExplicitSpecialization &&
8530 NewTemplateDecl->getInstantiatedFromMemberTemplate()) {
8531 NewTemplateDecl->setMemberSpecialization();
8532 assert(OldTemplateDecl->isMemberSpecialization());
8536 // This needs to happen first so that 'inline' propagates.
8537 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl));
8539 if (isa<CXXMethodDecl>(NewFD))
8540 NewFD->setAccess(OldDecl->getAccess());
8544 // Semantic checking for this function declaration (in isolation).
8546 if (getLangOpts().CPlusPlus) {
8547 // C++-specific checks.
8548 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) {
8549 CheckConstructor(Constructor);
8550 } else if (CXXDestructorDecl *Destructor =
8551 dyn_cast<CXXDestructorDecl>(NewFD)) {
8552 CXXRecordDecl *Record = Destructor->getParent();
8553 QualType ClassType = Context.getTypeDeclType(Record);
8555 // FIXME: Shouldn't we be able to perform this check even when the class
8556 // type is dependent? Both gcc and edg can handle that.
8557 if (!ClassType->isDependentType()) {
8558 DeclarationName Name
8559 = Context.DeclarationNames.getCXXDestructorName(
8560 Context.getCanonicalType(ClassType));
8561 if (NewFD->getDeclName() != Name) {
8562 Diag(NewFD->getLocation(), diag::err_destructor_name);
8563 NewFD->setInvalidDecl();
8564 return Redeclaration;
8567 } else if (CXXConversionDecl *Conversion
8568 = dyn_cast<CXXConversionDecl>(NewFD)) {
8569 ActOnConversionDeclarator(Conversion);
8572 // Find any virtual functions that this function overrides.
8573 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(NewFD)) {
8574 if (!Method->isFunctionTemplateSpecialization() &&
8575 !Method->getDescribedFunctionTemplate() &&
8576 Method->isCanonicalDecl()) {
8577 if (AddOverriddenMethods(Method->getParent(), Method)) {
8578 // If the function was marked as "static", we have a problem.
8579 if (NewFD->getStorageClass() == SC_Static) {
8580 ReportOverrides(*this, diag::err_static_overrides_virtual, Method);
8585 if (Method->isStatic())
8586 checkThisInStaticMemberFunctionType(Method);
8589 // Extra checking for C++ overloaded operators (C++ [over.oper]).
8590 if (NewFD->isOverloadedOperator() &&
8591 CheckOverloadedOperatorDeclaration(NewFD)) {
8592 NewFD->setInvalidDecl();
8593 return Redeclaration;
8596 // Extra checking for C++0x literal operators (C++0x [over.literal]).
8597 if (NewFD->getLiteralIdentifier() &&
8598 CheckLiteralOperatorDeclaration(NewFD)) {
8599 NewFD->setInvalidDecl();
8600 return Redeclaration;
8603 // In C++, check default arguments now that we have merged decls. Unless
8604 // the lexical context is the class, because in this case this is done
8605 // during delayed parsing anyway.
8606 if (!CurContext->isRecord())
8607 CheckCXXDefaultArguments(NewFD);
8609 // If this function declares a builtin function, check the type of this
8610 // declaration against the expected type for the builtin.
8611 if (unsigned BuiltinID = NewFD->getBuiltinID()) {
8612 ASTContext::GetBuiltinTypeError Error;
8613 LookupPredefedObjCSuperType(*this, S, NewFD->getIdentifier());
8614 QualType T = Context.GetBuiltinType(BuiltinID, Error);
8615 if (!T.isNull() && !Context.hasSameType(T, NewFD->getType())) {
8616 // The type of this function differs from the type of the builtin,
8617 // so forget about the builtin entirely.
8618 Context.BuiltinInfo.forgetBuiltin(BuiltinID, Context.Idents);
8622 // If this function is declared as being extern "C", then check to see if
8623 // the function returns a UDT (class, struct, or union type) that is not C
8624 // compatible, and if it does, warn the user.
8625 // But, issue any diagnostic on the first declaration only.
8626 if (Previous.empty() && NewFD->isExternC()) {
8627 QualType R = NewFD->getReturnType();
8628 if (R->isIncompleteType() && !R->isVoidType())
8629 Diag(NewFD->getLocation(), diag::warn_return_value_udt_incomplete)
8631 else if (!R.isPODType(Context) && !R->isVoidType() &&
8632 !R->isObjCObjectPointerType())
8633 Diag(NewFD->getLocation(), diag::warn_return_value_udt) << NewFD << R;
8636 return Redeclaration;
8639 void Sema::CheckMain(FunctionDecl* FD, const DeclSpec& DS) {
8640 // C++11 [basic.start.main]p3:
8641 // A program that [...] declares main to be inline, static or
8642 // constexpr is ill-formed.
8643 // C11 6.7.4p4: In a hosted environment, no function specifier(s) shall
8644 // appear in a declaration of main.
8645 // static main is not an error under C99, but we should warn about it.
8646 // We accept _Noreturn main as an extension.
8647 if (FD->getStorageClass() == SC_Static)
8648 Diag(DS.getStorageClassSpecLoc(), getLangOpts().CPlusPlus
8649 ? diag::err_static_main : diag::warn_static_main)
8650 << FixItHint::CreateRemoval(DS.getStorageClassSpecLoc());
8651 if (FD->isInlineSpecified())
8652 Diag(DS.getInlineSpecLoc(), diag::err_inline_main)
8653 << FixItHint::CreateRemoval(DS.getInlineSpecLoc());
8654 if (DS.isNoreturnSpecified()) {
8655 SourceLocation NoreturnLoc = DS.getNoreturnSpecLoc();
8656 SourceRange NoreturnRange(NoreturnLoc, getLocForEndOfToken(NoreturnLoc));
8657 Diag(NoreturnLoc, diag::ext_noreturn_main);
8658 Diag(NoreturnLoc, diag::note_main_remove_noreturn)
8659 << FixItHint::CreateRemoval(NoreturnRange);
8661 if (FD->isConstexpr()) {
8662 Diag(DS.getConstexprSpecLoc(), diag::err_constexpr_main)
8663 << FixItHint::CreateRemoval(DS.getConstexprSpecLoc());
8664 FD->setConstexpr(false);
8667 if (getLangOpts().OpenCL) {
8668 Diag(FD->getLocation(), diag::err_opencl_no_main)
8669 << FD->hasAttr<OpenCLKernelAttr>();
8670 FD->setInvalidDecl();
8674 QualType T = FD->getType();
8675 assert(T->isFunctionType() && "function decl is not of function type");
8676 const FunctionType* FT = T->castAs<FunctionType>();
8678 if (getLangOpts().GNUMode && !getLangOpts().CPlusPlus) {
8679 // In C with GNU extensions we allow main() to have non-integer return
8680 // type, but we should warn about the extension, and we disable the
8681 // implicit-return-zero rule.
8683 // GCC in C mode accepts qualified 'int'.
8684 if (Context.hasSameUnqualifiedType(FT->getReturnType(), Context.IntTy))
8685 FD->setHasImplicitReturnZero(true);
8687 Diag(FD->getTypeSpecStartLoc(), diag::ext_main_returns_nonint);
8688 SourceRange RTRange = FD->getReturnTypeSourceRange();
8689 if (RTRange.isValid())
8690 Diag(RTRange.getBegin(), diag::note_main_change_return_type)
8691 << FixItHint::CreateReplacement(RTRange, "int");
8694 // In C and C++, main magically returns 0 if you fall off the end;
8695 // set the flag which tells us that.
8696 // This is C++ [basic.start.main]p5 and C99 5.1.2.2.3.
8698 // All the standards say that main() should return 'int'.
8699 if (Context.hasSameType(FT->getReturnType(), Context.IntTy))
8700 FD->setHasImplicitReturnZero(true);
8702 // Otherwise, this is just a flat-out error.
8703 SourceRange RTRange = FD->getReturnTypeSourceRange();
8704 Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint)
8705 << (RTRange.isValid() ? FixItHint::CreateReplacement(RTRange, "int")
8707 FD->setInvalidDecl(true);
8711 // Treat protoless main() as nullary.
8712 if (isa<FunctionNoProtoType>(FT)) return;
8714 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT);
8715 unsigned nparams = FTP->getNumParams();
8716 assert(FD->getNumParams() == nparams);
8718 bool HasExtraParameters = (nparams > 3);
8720 if (FTP->isVariadic()) {
8721 Diag(FD->getLocation(), diag::ext_variadic_main);
8722 // FIXME: if we had information about the location of the ellipsis, we
8723 // could add a FixIt hint to remove it as a parameter.
8726 // Darwin passes an undocumented fourth argument of type char**. If
8727 // other platforms start sprouting these, the logic below will start
8729 if (nparams == 4 && Context.getTargetInfo().getTriple().isOSDarwin())
8730 HasExtraParameters = false;
8732 if (HasExtraParameters) {
8733 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams;
8734 FD->setInvalidDecl(true);
8738 // FIXME: a lot of the following diagnostics would be improved
8739 // if we had some location information about types.
8742 Context.getPointerType(Context.getPointerType(Context.CharTy));
8743 QualType Expected[] = { Context.IntTy, CharPP, CharPP, CharPP };
8745 for (unsigned i = 0; i < nparams; ++i) {
8746 QualType AT = FTP->getParamType(i);
8748 bool mismatch = true;
8750 if (Context.hasSameUnqualifiedType(AT, Expected[i]))
8752 else if (Expected[i] == CharPP) {
8753 // As an extension, the following forms are okay:
8755 // char const * const *
8758 QualifierCollector qs;
8759 const PointerType* PT;
8760 if ((PT = qs.strip(AT)->getAs<PointerType>()) &&
8761 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) &&
8762 Context.hasSameType(QualType(qs.strip(PT->getPointeeType()), 0),
8765 mismatch = !qs.empty();
8770 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i];
8771 // TODO: suggest replacing given type with expected type
8772 FD->setInvalidDecl(true);
8776 if (nparams == 1 && !FD->isInvalidDecl()) {
8777 Diag(FD->getLocation(), diag::warn_main_one_arg);
8780 if (!FD->isInvalidDecl() && FD->getDescribedFunctionTemplate()) {
8781 Diag(FD->getLocation(), diag::err_mainlike_template_decl) << FD;
8782 FD->setInvalidDecl();
8786 void Sema::CheckMSVCRTEntryPoint(FunctionDecl *FD) {
8787 QualType T = FD->getType();
8788 assert(T->isFunctionType() && "function decl is not of function type");
8789 const FunctionType *FT = T->castAs<FunctionType>();
8791 // Set an implicit return of 'zero' if the function can return some integral,
8792 // enumeration, pointer or nullptr type.
8793 if (FT->getReturnType()->isIntegralOrEnumerationType() ||
8794 FT->getReturnType()->isAnyPointerType() ||
8795 FT->getReturnType()->isNullPtrType())
8796 // DllMain is exempt because a return value of zero means it failed.
8797 if (FD->getName() != "DllMain")
8798 FD->setHasImplicitReturnZero(true);
8800 if (!FD->isInvalidDecl() && FD->getDescribedFunctionTemplate()) {
8801 Diag(FD->getLocation(), diag::err_mainlike_template_decl) << FD;
8802 FD->setInvalidDecl();
8806 bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) {
8807 // FIXME: Need strict checking. In C89, we need to check for
8808 // any assignment, increment, decrement, function-calls, or
8809 // commas outside of a sizeof. In C99, it's the same list,
8810 // except that the aforementioned are allowed in unevaluated
8811 // expressions. Everything else falls under the
8812 // "may accept other forms of constant expressions" exception.
8813 // (We never end up here for C++, so the constant expression
8814 // rules there don't matter.)
8815 const Expr *Culprit;
8816 if (Init->isConstantInitializer(Context, false, &Culprit))
8818 Diag(Culprit->getExprLoc(), diag::err_init_element_not_constant)
8819 << Culprit->getSourceRange();
8824 // Visits an initialization expression to see if OrigDecl is evaluated in
8825 // its own initialization and throws a warning if it does.
8826 class SelfReferenceChecker
8827 : public EvaluatedExprVisitor<SelfReferenceChecker> {
8832 bool isReferenceType;
8835 llvm::SmallVector<unsigned, 4> InitFieldIndex;
8838 typedef EvaluatedExprVisitor<SelfReferenceChecker> Inherited;
8840 SelfReferenceChecker(Sema &S, Decl *OrigDecl) : Inherited(S.Context),
8841 S(S), OrigDecl(OrigDecl) {
8843 isRecordType = false;
8844 isReferenceType = false;
8846 if (ValueDecl *VD = dyn_cast<ValueDecl>(OrigDecl)) {
8847 isPODType = VD->getType().isPODType(S.Context);
8848 isRecordType = VD->getType()->isRecordType();
8849 isReferenceType = VD->getType()->isReferenceType();
8853 // For most expressions, just call the visitor. For initializer lists,
8854 // track the index of the field being initialized since fields are
8855 // initialized in order allowing use of previously initialized fields.
8856 void CheckExpr(Expr *E) {
8857 InitListExpr *InitList = dyn_cast<InitListExpr>(E);
8863 // Track and increment the index here.
8865 InitFieldIndex.push_back(0);
8866 for (auto Child : InitList->children()) {
8867 CheckExpr(cast<Expr>(Child));
8868 ++InitFieldIndex.back();
8870 InitFieldIndex.pop_back();
8873 // Returns true if MemberExpr is checked and no futher checking is needed.
8874 // Returns false if additional checking is required.
8875 bool CheckInitListMemberExpr(MemberExpr *E, bool CheckReference) {
8876 llvm::SmallVector<FieldDecl*, 4> Fields;
8878 bool ReferenceField = false;
8880 // Get the field memebers used.
8881 while (MemberExpr *ME = dyn_cast<MemberExpr>(Base)) {
8882 FieldDecl *FD = dyn_cast<FieldDecl>(ME->getMemberDecl());
8885 Fields.push_back(FD);
8886 if (FD->getType()->isReferenceType())
8887 ReferenceField = true;
8888 Base = ME->getBase()->IgnoreParenImpCasts();
8891 // Keep checking only if the base Decl is the same.
8892 DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Base);
8893 if (!DRE || DRE->getDecl() != OrigDecl)
8896 // A reference field can be bound to an unininitialized field.
8897 if (CheckReference && !ReferenceField)
8900 // Convert FieldDecls to their index number.
8901 llvm::SmallVector<unsigned, 4> UsedFieldIndex;
8902 for (const FieldDecl *I : llvm::reverse(Fields))
8903 UsedFieldIndex.push_back(I->getFieldIndex());
8905 // See if a warning is needed by checking the first difference in index
8906 // numbers. If field being used has index less than the field being
8907 // initialized, then the use is safe.
8908 for (auto UsedIter = UsedFieldIndex.begin(),
8909 UsedEnd = UsedFieldIndex.end(),
8910 OrigIter = InitFieldIndex.begin(),
8911 OrigEnd = InitFieldIndex.end();
8912 UsedIter != UsedEnd && OrigIter != OrigEnd; ++UsedIter, ++OrigIter) {
8913 if (*UsedIter < *OrigIter)
8915 if (*UsedIter > *OrigIter)
8919 // TODO: Add a different warning which will print the field names.
8920 HandleDeclRefExpr(DRE);
8924 // For most expressions, the cast is directly above the DeclRefExpr.
8925 // For conditional operators, the cast can be outside the conditional
8926 // operator if both expressions are DeclRefExpr's.
8927 void HandleValue(Expr *E) {
8928 E = E->IgnoreParens();
8929 if (DeclRefExpr* DRE = dyn_cast<DeclRefExpr>(E)) {
8930 HandleDeclRefExpr(DRE);
8934 if (ConditionalOperator *CO = dyn_cast<ConditionalOperator>(E)) {
8935 Visit(CO->getCond());
8936 HandleValue(CO->getTrueExpr());
8937 HandleValue(CO->getFalseExpr());
8941 if (BinaryConditionalOperator *BCO =
8942 dyn_cast<BinaryConditionalOperator>(E)) {
8943 Visit(BCO->getCond());
8944 HandleValue(BCO->getFalseExpr());
8948 if (OpaqueValueExpr *OVE = dyn_cast<OpaqueValueExpr>(E)) {
8949 HandleValue(OVE->getSourceExpr());
8953 if (BinaryOperator *BO = dyn_cast<BinaryOperator>(E)) {
8954 if (BO->getOpcode() == BO_Comma) {
8955 Visit(BO->getLHS());
8956 HandleValue(BO->getRHS());
8961 if (isa<MemberExpr>(E)) {
8963 if (CheckInitListMemberExpr(cast<MemberExpr>(E),
8964 false /*CheckReference*/))
8968 Expr *Base = E->IgnoreParenImpCasts();
8969 while (MemberExpr *ME = dyn_cast<MemberExpr>(Base)) {
8970 // Check for static member variables and don't warn on them.
8971 if (!isa<FieldDecl>(ME->getMemberDecl()))
8973 Base = ME->getBase()->IgnoreParenImpCasts();
8975 if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Base))
8976 HandleDeclRefExpr(DRE);
8983 // Reference types not handled in HandleValue are handled here since all
8984 // uses of references are bad, not just r-value uses.
8985 void VisitDeclRefExpr(DeclRefExpr *E) {
8986 if (isReferenceType)
8987 HandleDeclRefExpr(E);
8990 void VisitImplicitCastExpr(ImplicitCastExpr *E) {
8991 if (E->getCastKind() == CK_LValueToRValue) {
8992 HandleValue(E->getSubExpr());
8996 Inherited::VisitImplicitCastExpr(E);
8999 void VisitMemberExpr(MemberExpr *E) {
9001 if (CheckInitListMemberExpr(E, true /*CheckReference*/))
9005 // Don't warn on arrays since they can be treated as pointers.
9006 if (E->getType()->canDecayToPointerType()) return;
9008 // Warn when a non-static method call is followed by non-static member
9009 // field accesses, which is followed by a DeclRefExpr.
9010 CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(E->getMemberDecl());
9011 bool Warn = (MD && !MD->isStatic());
9012 Expr *Base = E->getBase()->IgnoreParenImpCasts();
9013 while (MemberExpr *ME = dyn_cast<MemberExpr>(Base)) {
9014 if (!isa<FieldDecl>(ME->getMemberDecl()))
9016 Base = ME->getBase()->IgnoreParenImpCasts();
9019 if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Base)) {
9021 HandleDeclRefExpr(DRE);
9025 // The base of a MemberExpr is not a MemberExpr or a DeclRefExpr.
9026 // Visit that expression.
9030 void VisitCXXOperatorCallExpr(CXXOperatorCallExpr *E) {
9031 Expr *Callee = E->getCallee();
9033 if (isa<UnresolvedLookupExpr>(Callee))
9034 return Inherited::VisitCXXOperatorCallExpr(E);
9037 for (auto Arg: E->arguments())
9038 HandleValue(Arg->IgnoreParenImpCasts());
9041 void VisitUnaryOperator(UnaryOperator *E) {
9042 // For POD record types, addresses of its own members are well-defined.
9043 if (E->getOpcode() == UO_AddrOf && isRecordType &&
9044 isa<MemberExpr>(E->getSubExpr()->IgnoreParens())) {
9046 HandleValue(E->getSubExpr());
9050 if (E->isIncrementDecrementOp()) {
9051 HandleValue(E->getSubExpr());
9055 Inherited::VisitUnaryOperator(E);
9058 void VisitObjCMessageExpr(ObjCMessageExpr *E) {}
9060 void VisitCXXConstructExpr(CXXConstructExpr *E) {
9061 if (E->getConstructor()->isCopyConstructor()) {
9062 Expr *ArgExpr = E->getArg(0);
9063 if (InitListExpr *ILE = dyn_cast<InitListExpr>(ArgExpr))
9064 if (ILE->getNumInits() == 1)
9065 ArgExpr = ILE->getInit(0);
9066 if (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(ArgExpr))
9067 if (ICE->getCastKind() == CK_NoOp)
9068 ArgExpr = ICE->getSubExpr();
9069 HandleValue(ArgExpr);
9072 Inherited::VisitCXXConstructExpr(E);
9075 void VisitCallExpr(CallExpr *E) {
9076 // Treat std::move as a use.
9077 if (E->getNumArgs() == 1) {
9078 if (FunctionDecl *FD = E->getDirectCallee()) {
9079 if (FD->isInStdNamespace() && FD->getIdentifier() &&
9080 FD->getIdentifier()->isStr("move")) {
9081 HandleValue(E->getArg(0));
9087 Inherited::VisitCallExpr(E);
9090 void VisitBinaryOperator(BinaryOperator *E) {
9091 if (E->isCompoundAssignmentOp()) {
9092 HandleValue(E->getLHS());
9097 Inherited::VisitBinaryOperator(E);
9100 // A custom visitor for BinaryConditionalOperator is needed because the
9101 // regular visitor would check the condition and true expression separately
9102 // but both point to the same place giving duplicate diagnostics.
9103 void VisitBinaryConditionalOperator(BinaryConditionalOperator *E) {
9104 Visit(E->getCond());
9105 Visit(E->getFalseExpr());
9108 void HandleDeclRefExpr(DeclRefExpr *DRE) {
9109 Decl* ReferenceDecl = DRE->getDecl();
9110 if (OrigDecl != ReferenceDecl) return;
9112 if (isReferenceType) {
9113 diag = diag::warn_uninit_self_reference_in_reference_init;
9114 } else if (cast<VarDecl>(OrigDecl)->isStaticLocal()) {
9115 diag = diag::warn_static_self_reference_in_init;
9116 } else if (isa<TranslationUnitDecl>(OrigDecl->getDeclContext()) ||
9117 isa<NamespaceDecl>(OrigDecl->getDeclContext()) ||
9118 DRE->getDecl()->getType()->isRecordType()) {
9119 diag = diag::warn_uninit_self_reference_in_init;
9121 // Local variables will be handled by the CFG analysis.
9125 S.DiagRuntimeBehavior(DRE->getLocStart(), DRE,
9127 << DRE->getNameInfo().getName()
9128 << OrigDecl->getLocation()
9129 << DRE->getSourceRange());
9133 /// CheckSelfReference - Warns if OrigDecl is used in expression E.
9134 static void CheckSelfReference(Sema &S, Decl* OrigDecl, Expr *E,
9136 // Parameters arguments are occassionially constructed with itself,
9137 // for instance, in recursive functions. Skip them.
9138 if (isa<ParmVarDecl>(OrigDecl))
9141 E = E->IgnoreParens();
9143 // Skip checking T a = a where T is not a record or reference type.
9144 // Doing so is a way to silence uninitialized warnings.
9145 if (!DirectInit && !cast<VarDecl>(OrigDecl)->getType()->isRecordType())
9146 if (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(E))
9147 if (ICE->getCastKind() == CK_LValueToRValue)
9148 if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(ICE->getSubExpr()))
9149 if (DRE->getDecl() == OrigDecl)
9152 SelfReferenceChecker(S, OrigDecl).CheckExpr(E);
9154 } // end anonymous namespace
9156 QualType Sema::deduceVarTypeFromInitializer(VarDecl *VDecl,
9157 DeclarationName Name, QualType Type,
9158 TypeSourceInfo *TSI,
9159 SourceRange Range, bool DirectInit,
9161 bool IsInitCapture = !VDecl;
9162 assert((!VDecl || !VDecl->isInitCapture()) &&
9163 "init captures are expected to be deduced prior to initialization");
9165 ArrayRef<Expr *> DeduceInits = Init;
9167 if (auto *PL = dyn_cast<ParenListExpr>(Init))
9168 DeduceInits = PL->exprs();
9169 else if (auto *IL = dyn_cast<InitListExpr>(Init))
9170 DeduceInits = IL->inits();
9173 // Deduction only works if we have exactly one source expression.
9174 if (DeduceInits.empty()) {
9175 // It isn't possible to write this directly, but it is possible to
9176 // end up in this situation with "auto x(some_pack...);"
9177 Diag(Init->getLocStart(), IsInitCapture
9178 ? diag::err_init_capture_no_expression
9179 : diag::err_auto_var_init_no_expression)
9180 << Name << Type << Range;
9184 if (DeduceInits.size() > 1) {
9185 Diag(DeduceInits[1]->getLocStart(),
9186 IsInitCapture ? diag::err_init_capture_multiple_expressions
9187 : diag::err_auto_var_init_multiple_expressions)
9188 << Name << Type << Range;
9192 Expr *DeduceInit = DeduceInits[0];
9193 if (DirectInit && isa<InitListExpr>(DeduceInit)) {
9194 Diag(Init->getLocStart(), IsInitCapture
9195 ? diag::err_init_capture_paren_braces
9196 : diag::err_auto_var_init_paren_braces)
9197 << isa<InitListExpr>(Init) << Name << Type << Range;
9201 // Expressions default to 'id' when we're in a debugger.
9202 bool DefaultedAnyToId = false;
9203 if (getLangOpts().DebuggerCastResultToId &&
9204 Init->getType() == Context.UnknownAnyTy && !IsInitCapture) {
9205 ExprResult Result = forceUnknownAnyToType(Init, Context.getObjCIdType());
9206 if (Result.isInvalid()) {
9209 Init = Result.get();
9210 DefaultedAnyToId = true;
9213 QualType DeducedType;
9214 if (DeduceAutoType(TSI, DeduceInit, DeducedType) == DAR_Failed) {
9216 DiagnoseAutoDeductionFailure(VDecl, DeduceInit);
9217 else if (isa<InitListExpr>(Init))
9218 Diag(Range.getBegin(),
9219 diag::err_init_capture_deduction_failure_from_init_list)
9221 << (DeduceInit->getType().isNull() ? TSI->getType()
9222 : DeduceInit->getType())
9223 << DeduceInit->getSourceRange();
9225 Diag(Range.getBegin(), diag::err_init_capture_deduction_failure)
9226 << Name << TSI->getType()
9227 << (DeduceInit->getType().isNull() ? TSI->getType()
9228 : DeduceInit->getType())
9229 << DeduceInit->getSourceRange();
9232 // Warn if we deduced 'id'. 'auto' usually implies type-safety, but using
9233 // 'id' instead of a specific object type prevents most of our usual
9235 // We only want to warn outside of template instantiations, though:
9236 // inside a template, the 'id' could have come from a parameter.
9237 if (ActiveTemplateInstantiations.empty() && !DefaultedAnyToId &&
9238 !IsInitCapture && !DeducedType.isNull() && DeducedType->isObjCIdType()) {
9239 SourceLocation Loc = TSI->getTypeLoc().getBeginLoc();
9240 Diag(Loc, diag::warn_auto_var_is_id) << Name << Range;
9246 /// AddInitializerToDecl - Adds the initializer Init to the
9247 /// declaration dcl. If DirectInit is true, this is C++ direct
9248 /// initialization rather than copy initialization.
9249 void Sema::AddInitializerToDecl(Decl *RealDecl, Expr *Init,
9250 bool DirectInit, bool TypeMayContainAuto) {
9251 // If there is no declaration, there was an error parsing it. Just ignore
9253 if (!RealDecl || RealDecl->isInvalidDecl()) {
9254 CorrectDelayedTyposInExpr(Init, dyn_cast_or_null<VarDecl>(RealDecl));
9258 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) {
9259 // Pure-specifiers are handled in ActOnPureSpecifier.
9260 Diag(Method->getLocation(), diag::err_member_function_initialization)
9261 << Method->getDeclName() << Init->getSourceRange();
9262 Method->setInvalidDecl();
9266 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl);
9268 assert(!isa<FieldDecl>(RealDecl) && "field init shouldn't get here");
9269 Diag(RealDecl->getLocation(), diag::err_illegal_initializer);
9270 RealDecl->setInvalidDecl();
9274 // C++11 [decl.spec.auto]p6. Deduce the type which 'auto' stands in for.
9275 if (TypeMayContainAuto && VDecl->getType()->isUndeducedType()) {
9276 // Attempt typo correction early so that the type of the init expression can
9277 // be deduced based on the chosen correction if the original init contains a
9279 ExprResult Res = CorrectDelayedTyposInExpr(Init, VDecl);
9280 if (!Res.isUsable()) {
9281 RealDecl->setInvalidDecl();
9286 QualType DeducedType = deduceVarTypeFromInitializer(
9287 VDecl, VDecl->getDeclName(), VDecl->getType(),
9288 VDecl->getTypeSourceInfo(), VDecl->getSourceRange(), DirectInit, Init);
9289 if (DeducedType.isNull()) {
9290 RealDecl->setInvalidDecl();
9294 VDecl->setType(DeducedType);
9295 assert(VDecl->isLinkageValid());
9297 // In ARC, infer lifetime.
9298 if (getLangOpts().ObjCAutoRefCount && inferObjCARCLifetime(VDecl))
9299 VDecl->setInvalidDecl();
9301 // If this is a redeclaration, check that the type we just deduced matches
9302 // the previously declared type.
9303 if (VarDecl *Old = VDecl->getPreviousDecl()) {
9304 // We never need to merge the type, because we cannot form an incomplete
9305 // array of auto, nor deduce such a type.
9306 MergeVarDeclTypes(VDecl, Old, /*MergeTypeWithPrevious*/ false);
9309 // Check the deduced type is valid for a variable declaration.
9310 CheckVariableDeclarationType(VDecl);
9311 if (VDecl->isInvalidDecl())
9315 // dllimport cannot be used on variable definitions.
9316 if (VDecl->hasAttr<DLLImportAttr>() && !VDecl->isStaticDataMember()) {
9317 Diag(VDecl->getLocation(), diag::err_attribute_dllimport_data_definition);
9318 VDecl->setInvalidDecl();
9322 if (VDecl->isLocalVarDecl() && VDecl->hasExternalStorage()) {
9323 // C99 6.7.8p5. C++ has no such restriction, but that is a defect.
9324 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init);
9325 VDecl->setInvalidDecl();
9329 if (!VDecl->getType()->isDependentType()) {
9330 // A definition must end up with a complete type, which means it must be
9331 // complete with the restriction that an array type might be completed by
9332 // the initializer; note that later code assumes this restriction.
9333 QualType BaseDeclType = VDecl->getType();
9334 if (const ArrayType *Array = Context.getAsIncompleteArrayType(BaseDeclType))
9335 BaseDeclType = Array->getElementType();
9336 if (RequireCompleteType(VDecl->getLocation(), BaseDeclType,
9337 diag::err_typecheck_decl_incomplete_type)) {
9338 RealDecl->setInvalidDecl();
9342 // The variable can not have an abstract class type.
9343 if (RequireNonAbstractType(VDecl->getLocation(), VDecl->getType(),
9344 diag::err_abstract_type_in_decl,
9345 AbstractVariableType))
9346 VDecl->setInvalidDecl();
9350 if ((Def = VDecl->getDefinition()) && Def != VDecl) {
9351 NamedDecl *Hidden = nullptr;
9352 if (!hasVisibleDefinition(Def, &Hidden) &&
9353 (VDecl->getFormalLinkage() == InternalLinkage ||
9354 VDecl->getDescribedVarTemplate() ||
9355 VDecl->getNumTemplateParameterLists() ||
9356 VDecl->getDeclContext()->isDependentContext())) {
9357 // The previous definition is hidden, and multiple definitions are
9358 // permitted (in separate TUs). Form another definition of it.
9360 Diag(VDecl->getLocation(), diag::err_redefinition)
9361 << VDecl->getDeclName();
9362 Diag(Def->getLocation(), diag::note_previous_definition);
9363 VDecl->setInvalidDecl();
9368 if (getLangOpts().CPlusPlus) {
9369 // C++ [class.static.data]p4
9370 // If a static data member is of const integral or const
9371 // enumeration type, its declaration in the class definition can
9372 // specify a constant-initializer which shall be an integral
9373 // constant expression (5.19). In that case, the member can appear
9374 // in integral constant expressions. The member shall still be
9375 // defined in a namespace scope if it is used in the program and the
9376 // namespace scope definition shall not contain an initializer.
9378 // We already performed a redefinition check above, but for static
9379 // data members we also need to check whether there was an in-class
9380 // declaration with an initializer.
9381 if (VDecl->isStaticDataMember() && VDecl->getCanonicalDecl()->hasInit()) {
9382 Diag(Init->getExprLoc(), diag::err_static_data_member_reinitialization)
9383 << VDecl->getDeclName();
9384 Diag(VDecl->getCanonicalDecl()->getInit()->getExprLoc(),
9385 diag::note_previous_initializer)
9390 if (VDecl->hasLocalStorage())
9391 getCurFunction()->setHasBranchProtectedScope();
9393 if (DiagnoseUnexpandedParameterPack(Init, UPPC_Initializer)) {
9394 VDecl->setInvalidDecl();
9399 // OpenCL 1.1 6.5.2: "Variables allocated in the __local address space inside
9400 // a kernel function cannot be initialized."
9401 if (VDecl->getType().getAddressSpace() == LangAS::opencl_local) {
9402 Diag(VDecl->getLocation(), diag::err_local_cant_init);
9403 VDecl->setInvalidDecl();
9407 // Get the decls type and save a reference for later, since
9408 // CheckInitializerTypes may change it.
9409 QualType DclT = VDecl->getType(), SavT = DclT;
9411 // Expressions default to 'id' when we're in a debugger
9412 // and we are assigning it to a variable of Objective-C pointer type.
9413 if (getLangOpts().DebuggerCastResultToId && DclT->isObjCObjectPointerType() &&
9414 Init->getType() == Context.UnknownAnyTy) {
9415 ExprResult Result = forceUnknownAnyToType(Init, Context.getObjCIdType());
9416 if (Result.isInvalid()) {
9417 VDecl->setInvalidDecl();
9420 Init = Result.get();
9423 // Perform the initialization.
9424 ParenListExpr *CXXDirectInit = dyn_cast<ParenListExpr>(Init);
9425 if (!VDecl->isInvalidDecl()) {
9426 InitializedEntity Entity = InitializedEntity::InitializeVariable(VDecl);
9427 InitializationKind Kind =
9430 ? InitializationKind::CreateDirect(VDecl->getLocation(),
9431 Init->getLocStart(),
9433 : InitializationKind::CreateDirectList(VDecl->getLocation())
9434 : InitializationKind::CreateCopy(VDecl->getLocation(),
9435 Init->getLocStart());
9437 MultiExprArg Args = Init;
9439 Args = MultiExprArg(CXXDirectInit->getExprs(),
9440 CXXDirectInit->getNumExprs());
9442 // Try to correct any TypoExprs in the initialization arguments.
9443 for (size_t Idx = 0; Idx < Args.size(); ++Idx) {
9444 ExprResult Res = CorrectDelayedTyposInExpr(
9445 Args[Idx], VDecl, [this, Entity, Kind](Expr *E) {
9446 InitializationSequence Init(*this, Entity, Kind, MultiExprArg(E));
9447 return Init.Failed() ? ExprError() : E;
9449 if (Res.isInvalid()) {
9450 VDecl->setInvalidDecl();
9451 } else if (Res.get() != Args[Idx]) {
9452 Args[Idx] = Res.get();
9455 if (VDecl->isInvalidDecl())
9458 InitializationSequence InitSeq(*this, Entity, Kind, Args);
9459 ExprResult Result = InitSeq.Perform(*this, Entity, Kind, Args, &DclT);
9460 if (Result.isInvalid()) {
9461 VDecl->setInvalidDecl();
9465 Init = Result.getAs<Expr>();
9468 // Check for self-references within variable initializers.
9469 // Variables declared within a function/method body (except for references)
9470 // are handled by a dataflow analysis.
9471 if (!VDecl->hasLocalStorage() || VDecl->getType()->isRecordType() ||
9472 VDecl->getType()->isReferenceType()) {
9473 CheckSelfReference(*this, RealDecl, Init, DirectInit);
9476 // If the type changed, it means we had an incomplete type that was
9477 // completed by the initializer. For example:
9478 // int ary[] = { 1, 3, 5 };
9479 // "ary" transitions from an IncompleteArrayType to a ConstantArrayType.
9480 if (!VDecl->isInvalidDecl() && (DclT != SavT))
9481 VDecl->setType(DclT);
9483 if (!VDecl->isInvalidDecl()) {
9484 checkUnsafeAssigns(VDecl->getLocation(), VDecl->getType(), Init);
9486 if (VDecl->hasAttr<BlocksAttr>())
9487 checkRetainCycles(VDecl, Init);
9489 // It is safe to assign a weak reference into a strong variable.
9490 // Although this code can still have problems:
9491 // id x = self.weakProp;
9492 // id y = self.weakProp;
9493 // we do not warn to warn spuriously when 'x' and 'y' are on separate
9494 // paths through the function. This should be revisited if
9495 // -Wrepeated-use-of-weak is made flow-sensitive.
9496 if (VDecl->getType().getObjCLifetime() == Qualifiers::OCL_Strong &&
9497 !Diags.isIgnored(diag::warn_arc_repeated_use_of_weak,
9498 Init->getLocStart()))
9499 getCurFunction()->markSafeWeakUse(Init);
9502 // The initialization is usually a full-expression.
9504 // FIXME: If this is a braced initialization of an aggregate, it is not
9505 // an expression, and each individual field initializer is a separate
9506 // full-expression. For instance, in:
9508 // struct Temp { ~Temp(); };
9509 // struct S { S(Temp); };
9510 // struct T { S a, b; } t = { Temp(), Temp() }
9512 // we should destroy the first Temp before constructing the second.
9513 ExprResult Result = ActOnFinishFullExpr(Init, VDecl->getLocation(),
9515 VDecl->isConstexpr());
9516 if (Result.isInvalid()) {
9517 VDecl->setInvalidDecl();
9520 Init = Result.get();
9522 // Attach the initializer to the decl.
9523 VDecl->setInit(Init);
9525 if (VDecl->isLocalVarDecl()) {
9526 // C99 6.7.8p4: All the expressions in an initializer for an object that has
9527 // static storage duration shall be constant expressions or string literals.
9528 // C++ does not have this restriction.
9529 if (!getLangOpts().CPlusPlus && !VDecl->isInvalidDecl()) {
9530 const Expr *Culprit;
9531 if (VDecl->getStorageClass() == SC_Static)
9532 CheckForConstantInitializer(Init, DclT);
9533 // C89 is stricter than C99 for non-static aggregate types.
9534 // C89 6.5.7p3: All the expressions [...] in an initializer list
9535 // for an object that has aggregate or union type shall be
9536 // constant expressions.
9537 else if (!getLangOpts().C99 && VDecl->getType()->isAggregateType() &&
9538 isa<InitListExpr>(Init) &&
9539 !Init->isConstantInitializer(Context, false, &Culprit))
9540 Diag(Culprit->getExprLoc(),
9541 diag::ext_aggregate_init_not_constant)
9542 << Culprit->getSourceRange();
9544 } else if (VDecl->isStaticDataMember() &&
9545 VDecl->getLexicalDeclContext()->isRecord()) {
9546 // This is an in-class initialization for a static data member, e.g.,
9549 // static const int value = 17;
9552 // C++ [class.mem]p4:
9553 // A member-declarator can contain a constant-initializer only
9554 // if it declares a static member (9.4) of const integral or
9555 // const enumeration type, see 9.4.2.
9557 // C++11 [class.static.data]p3:
9558 // If a non-volatile const static data member is of integral or
9559 // enumeration type, its declaration in the class definition can
9560 // specify a brace-or-equal-initializer in which every initalizer-clause
9561 // that is an assignment-expression is a constant expression. A static
9562 // data member of literal type can be declared in the class definition
9563 // with the constexpr specifier; if so, its declaration shall specify a
9564 // brace-or-equal-initializer in which every initializer-clause that is
9565 // an assignment-expression is a constant expression.
9567 // Do nothing on dependent types.
9568 if (DclT->isDependentType()) {
9570 // Allow any 'static constexpr' members, whether or not they are of literal
9571 // type. We separately check that every constexpr variable is of literal
9573 } else if (VDecl->isConstexpr()) {
9575 // Require constness.
9576 } else if (!DclT.isConstQualified()) {
9577 Diag(VDecl->getLocation(), diag::err_in_class_initializer_non_const)
9578 << Init->getSourceRange();
9579 VDecl->setInvalidDecl();
9581 // We allow integer constant expressions in all cases.
9582 } else if (DclT->isIntegralOrEnumerationType()) {
9583 // Check whether the expression is a constant expression.
9585 if (getLangOpts().CPlusPlus11 && DclT.isVolatileQualified())
9586 // In C++11, a non-constexpr const static data member with an
9587 // in-class initializer cannot be volatile.
9588 Diag(VDecl->getLocation(), diag::err_in_class_initializer_volatile);
9589 else if (Init->isValueDependent())
9590 ; // Nothing to check.
9591 else if (Init->isIntegerConstantExpr(Context, &Loc))
9592 ; // Ok, it's an ICE!
9593 else if (Init->isEvaluatable(Context)) {
9594 // If we can constant fold the initializer through heroics, accept it,
9595 // but report this as a use of an extension for -pedantic.
9596 Diag(Loc, diag::ext_in_class_initializer_non_constant)
9597 << Init->getSourceRange();
9599 // Otherwise, this is some crazy unknown case. Report the issue at the
9600 // location provided by the isIntegerConstantExpr failed check.
9601 Diag(Loc, diag::err_in_class_initializer_non_constant)
9602 << Init->getSourceRange();
9603 VDecl->setInvalidDecl();
9606 // We allow foldable floating-point constants as an extension.
9607 } else if (DclT->isFloatingType()) { // also permits complex, which is ok
9608 // In C++98, this is a GNU extension. In C++11, it is not, but we support
9609 // it anyway and provide a fixit to add the 'constexpr'.
9610 if (getLangOpts().CPlusPlus11) {
9611 Diag(VDecl->getLocation(),
9612 diag::ext_in_class_initializer_float_type_cxx11)
9613 << DclT << Init->getSourceRange();
9614 Diag(VDecl->getLocStart(),
9615 diag::note_in_class_initializer_float_type_cxx11)
9616 << FixItHint::CreateInsertion(VDecl->getLocStart(), "constexpr ");
9618 Diag(VDecl->getLocation(), diag::ext_in_class_initializer_float_type)
9619 << DclT << Init->getSourceRange();
9621 if (!Init->isValueDependent() && !Init->isEvaluatable(Context)) {
9622 Diag(Init->getExprLoc(), diag::err_in_class_initializer_non_constant)
9623 << Init->getSourceRange();
9624 VDecl->setInvalidDecl();
9628 // Suggest adding 'constexpr' in C++11 for literal types.
9629 } else if (getLangOpts().CPlusPlus11 && DclT->isLiteralType(Context)) {
9630 Diag(VDecl->getLocation(), diag::err_in_class_initializer_literal_type)
9631 << DclT << Init->getSourceRange()
9632 << FixItHint::CreateInsertion(VDecl->getLocStart(), "constexpr ");
9633 VDecl->setConstexpr(true);
9636 Diag(VDecl->getLocation(), diag::err_in_class_initializer_bad_type)
9637 << DclT << Init->getSourceRange();
9638 VDecl->setInvalidDecl();
9640 } else if (VDecl->isFileVarDecl()) {
9641 if (VDecl->getStorageClass() == SC_Extern &&
9642 (!getLangOpts().CPlusPlus ||
9643 !(Context.getBaseElementType(VDecl->getType()).isConstQualified() ||
9644 VDecl->isExternC())) &&
9645 !isTemplateInstantiation(VDecl->getTemplateSpecializationKind()))
9646 Diag(VDecl->getLocation(), diag::warn_extern_init);
9648 // C99 6.7.8p4. All file scoped initializers need to be constant.
9649 if (!getLangOpts().CPlusPlus && !VDecl->isInvalidDecl())
9650 CheckForConstantInitializer(Init, DclT);
9653 // We will represent direct-initialization similarly to copy-initialization:
9654 // int x(1); -as-> int x = 1;
9655 // ClassType x(a,b,c); -as-> ClassType x = ClassType(a,b,c);
9657 // Clients that want to distinguish between the two forms, can check for
9658 // direct initializer using VarDecl::getInitStyle().
9659 // A major benefit is that clients that don't particularly care about which
9660 // exactly form was it (like the CodeGen) can handle both cases without
9661 // special case code.
9664 // The form of initialization (using parentheses or '=') is generally
9665 // insignificant, but does matter when the entity being initialized has a
9667 if (CXXDirectInit) {
9668 assert(DirectInit && "Call-style initializer must be direct init.");
9669 VDecl->setInitStyle(VarDecl::CallInit);
9670 } else if (DirectInit) {
9671 // This must be list-initialization. No other way is direct-initialization.
9672 VDecl->setInitStyle(VarDecl::ListInit);
9675 CheckCompleteVariableDeclaration(VDecl);
9678 /// ActOnInitializerError - Given that there was an error parsing an
9679 /// initializer for the given declaration, try to return to some form
9681 void Sema::ActOnInitializerError(Decl *D) {
9682 // Our main concern here is re-establishing invariants like "a
9683 // variable's type is either dependent or complete".
9684 if (!D || D->isInvalidDecl()) return;
9686 VarDecl *VD = dyn_cast<VarDecl>(D);
9689 // Auto types are meaningless if we can't make sense of the initializer.
9690 if (ParsingInitForAutoVars.count(D)) {
9691 D->setInvalidDecl();
9695 QualType Ty = VD->getType();
9696 if (Ty->isDependentType()) return;
9698 // Require a complete type.
9699 if (RequireCompleteType(VD->getLocation(),
9700 Context.getBaseElementType(Ty),
9701 diag::err_typecheck_decl_incomplete_type)) {
9702 VD->setInvalidDecl();
9706 // Require a non-abstract type.
9707 if (RequireNonAbstractType(VD->getLocation(), Ty,
9708 diag::err_abstract_type_in_decl,
9709 AbstractVariableType)) {
9710 VD->setInvalidDecl();
9714 // Don't bother complaining about constructors or destructors,
9718 void Sema::ActOnUninitializedDecl(Decl *RealDecl,
9719 bool TypeMayContainAuto) {
9720 // If there is no declaration, there was an error parsing it. Just ignore it.
9724 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) {
9725 QualType Type = Var->getType();
9727 // C++11 [dcl.spec.auto]p3
9728 if (TypeMayContainAuto && Type->getContainedAutoType()) {
9729 Diag(Var->getLocation(), diag::err_auto_var_requires_init)
9730 << Var->getDeclName() << Type;
9731 Var->setInvalidDecl();
9735 // C++11 [class.static.data]p3: A static data member can be declared with
9736 // the constexpr specifier; if so, its declaration shall specify
9737 // a brace-or-equal-initializer.
9738 // C++11 [dcl.constexpr]p1: The constexpr specifier shall be applied only to
9739 // the definition of a variable [...] or the declaration of a static data
9741 if (Var->isConstexpr() && !Var->isThisDeclarationADefinition()) {
9742 if (Var->isStaticDataMember())
9743 Diag(Var->getLocation(),
9744 diag::err_constexpr_static_mem_var_requires_init)
9745 << Var->getDeclName();
9747 Diag(Var->getLocation(), diag::err_invalid_constexpr_var_decl);
9748 Var->setInvalidDecl();
9752 // C++ Concepts TS [dcl.spec.concept]p1: [...] A variable template
9753 // definition having the concept specifier is called a variable concept. A
9754 // concept definition refers to [...] a variable concept and its initializer.
9755 if (VarTemplateDecl *VTD = Var->getDescribedVarTemplate()) {
9756 if (VTD->isConcept()) {
9757 Diag(Var->getLocation(), diag::err_var_concept_not_initialized);
9758 Var->setInvalidDecl();
9763 // OpenCL v1.1 s6.5.3: variables declared in the constant address space must
9765 if (!Var->isInvalidDecl() &&
9766 Var->getType().getAddressSpace() == LangAS::opencl_constant &&
9767 Var->getStorageClass() != SC_Extern && !Var->getInit()) {
9768 Diag(Var->getLocation(), diag::err_opencl_constant_no_init);
9769 Var->setInvalidDecl();
9773 switch (Var->isThisDeclarationADefinition()) {
9774 case VarDecl::Definition:
9775 if (!Var->isStaticDataMember() || !Var->getAnyInitializer())
9778 // We have an out-of-line definition of a static data member
9779 // that has an in-class initializer, so we type-check this like
9784 case VarDecl::DeclarationOnly:
9785 // It's only a declaration.
9787 // Block scope. C99 6.7p7: If an identifier for an object is
9788 // declared with no linkage (C99 6.2.2p6), the type for the
9789 // object shall be complete.
9790 if (!Type->isDependentType() && Var->isLocalVarDecl() &&
9791 !Var->hasLinkage() && !Var->isInvalidDecl() &&
9792 RequireCompleteType(Var->getLocation(), Type,
9793 diag::err_typecheck_decl_incomplete_type))
9794 Var->setInvalidDecl();
9796 // Make sure that the type is not abstract.
9797 if (!Type->isDependentType() && !Var->isInvalidDecl() &&
9798 RequireNonAbstractType(Var->getLocation(), Type,
9799 diag::err_abstract_type_in_decl,
9800 AbstractVariableType))
9801 Var->setInvalidDecl();
9802 if (!Type->isDependentType() && !Var->isInvalidDecl() &&
9803 Var->getStorageClass() == SC_PrivateExtern) {
9804 Diag(Var->getLocation(), diag::warn_private_extern);
9805 Diag(Var->getLocation(), diag::note_private_extern);
9810 case VarDecl::TentativeDefinition:
9811 // File scope. C99 6.9.2p2: A declaration of an identifier for an
9812 // object that has file scope without an initializer, and without a
9813 // storage-class specifier or with the storage-class specifier "static",
9814 // constitutes a tentative definition. Note: A tentative definition with
9815 // external linkage is valid (C99 6.2.2p5).
9816 if (!Var->isInvalidDecl()) {
9817 if (const IncompleteArrayType *ArrayT
9818 = Context.getAsIncompleteArrayType(Type)) {
9819 if (RequireCompleteType(Var->getLocation(),
9820 ArrayT->getElementType(),
9821 diag::err_illegal_decl_array_incomplete_type))
9822 Var->setInvalidDecl();
9823 } else if (Var->getStorageClass() == SC_Static) {
9824 // C99 6.9.2p3: If the declaration of an identifier for an object is
9825 // a tentative definition and has internal linkage (C99 6.2.2p3), the
9826 // declared type shall not be an incomplete type.
9827 // NOTE: code such as the following
9829 // struct s { int a; };
9830 // is accepted by gcc. Hence here we issue a warning instead of
9831 // an error and we do not invalidate the static declaration.
9832 // NOTE: to avoid multiple warnings, only check the first declaration.
9833 if (Var->isFirstDecl())
9834 RequireCompleteType(Var->getLocation(), Type,
9835 diag::ext_typecheck_decl_incomplete_type);
9839 // Record the tentative definition; we're done.
9840 if (!Var->isInvalidDecl())
9841 TentativeDefinitions.push_back(Var);
9845 // Provide a specific diagnostic for uninitialized variable
9846 // definitions with incomplete array type.
9847 if (Type->isIncompleteArrayType()) {
9848 Diag(Var->getLocation(),
9849 diag::err_typecheck_incomplete_array_needs_initializer);
9850 Var->setInvalidDecl();
9854 // Provide a specific diagnostic for uninitialized variable
9855 // definitions with reference type.
9856 if (Type->isReferenceType()) {
9857 Diag(Var->getLocation(), diag::err_reference_var_requires_init)
9858 << Var->getDeclName()
9859 << SourceRange(Var->getLocation(), Var->getLocation());
9860 Var->setInvalidDecl();
9864 // Do not attempt to type-check the default initializer for a
9865 // variable with dependent type.
9866 if (Type->isDependentType())
9869 if (Var->isInvalidDecl())
9872 if (!Var->hasAttr<AliasAttr>()) {
9873 if (RequireCompleteType(Var->getLocation(),
9874 Context.getBaseElementType(Type),
9875 diag::err_typecheck_decl_incomplete_type)) {
9876 Var->setInvalidDecl();
9883 // The variable can not have an abstract class type.
9884 if (RequireNonAbstractType(Var->getLocation(), Type,
9885 diag::err_abstract_type_in_decl,
9886 AbstractVariableType)) {
9887 Var->setInvalidDecl();
9891 // Check for jumps past the implicit initializer. C++0x
9892 // clarifies that this applies to a "variable with automatic
9893 // storage duration", not a "local variable".
9894 // C++11 [stmt.dcl]p3
9895 // A program that jumps from a point where a variable with automatic
9896 // storage duration is not in scope to a point where it is in scope is
9897 // ill-formed unless the variable has scalar type, class type with a
9898 // trivial default constructor and a trivial destructor, a cv-qualified
9899 // version of one of these types, or an array of one of the preceding
9900 // types and is declared without an initializer.
9901 if (getLangOpts().CPlusPlus && Var->hasLocalStorage()) {
9902 if (const RecordType *Record
9903 = Context.getBaseElementType(Type)->getAs<RecordType>()) {
9904 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record->getDecl());
9905 // Mark the function for further checking even if the looser rules of
9906 // C++11 do not require such checks, so that we can diagnose
9907 // incompatibilities with C++98.
9908 if (!CXXRecord->isPOD())
9909 getCurFunction()->setHasBranchProtectedScope();
9913 // C++03 [dcl.init]p9:
9914 // If no initializer is specified for an object, and the
9915 // object is of (possibly cv-qualified) non-POD class type (or
9916 // array thereof), the object shall be default-initialized; if
9917 // the object is of const-qualified type, the underlying class
9918 // type shall have a user-declared default
9919 // constructor. Otherwise, if no initializer is specified for
9920 // a non- static object, the object and its subobjects, if
9921 // any, have an indeterminate initial value); if the object
9922 // or any of its subobjects are of const-qualified type, the
9923 // program is ill-formed.
9924 // C++0x [dcl.init]p11:
9925 // If no initializer is specified for an object, the object is
9926 // default-initialized; [...].
9927 InitializedEntity Entity = InitializedEntity::InitializeVariable(Var);
9928 InitializationKind Kind
9929 = InitializationKind::CreateDefault(Var->getLocation());
9931 InitializationSequence InitSeq(*this, Entity, Kind, None);
9932 ExprResult Init = InitSeq.Perform(*this, Entity, Kind, None);
9933 if (Init.isInvalid())
9934 Var->setInvalidDecl();
9935 else if (Init.get()) {
9936 Var->setInit(MaybeCreateExprWithCleanups(Init.get()));
9937 // This is important for template substitution.
9938 Var->setInitStyle(VarDecl::CallInit);
9941 CheckCompleteVariableDeclaration(Var);
9945 void Sema::ActOnCXXForRangeDecl(Decl *D) {
9946 // If there is no declaration, there was an error parsing it. Ignore it.
9950 VarDecl *VD = dyn_cast<VarDecl>(D);
9952 Diag(D->getLocation(), diag::err_for_range_decl_must_be_var);
9953 D->setInvalidDecl();
9957 VD->setCXXForRangeDecl(true);
9959 // for-range-declaration cannot be given a storage class specifier.
9961 switch (VD->getStorageClass()) {
9970 case SC_PrivateExtern:
9981 Diag(VD->getOuterLocStart(), diag::err_for_range_storage_class)
9982 << VD->getDeclName() << Error;
9983 D->setInvalidDecl();
9988 Sema::ActOnCXXForRangeIdentifier(Scope *S, SourceLocation IdentLoc,
9989 IdentifierInfo *Ident,
9990 ParsedAttributes &Attrs,
9991 SourceLocation AttrEnd) {
9992 // C++1y [stmt.iter]p1:
9993 // A range-based for statement of the form
9994 // for ( for-range-identifier : for-range-initializer ) statement
9996 // for ( auto&& for-range-identifier : for-range-initializer ) statement
9997 DeclSpec DS(Attrs.getPool().getFactory());
9999 const char *PrevSpec;
10001 DS.SetTypeSpecType(DeclSpec::TST_auto, IdentLoc, PrevSpec, DiagID,
10002 getPrintingPolicy());
10004 Declarator D(DS, Declarator::ForContext);
10005 D.SetIdentifier(Ident, IdentLoc);
10006 D.takeAttributes(Attrs, AttrEnd);
10008 ParsedAttributes EmptyAttrs(Attrs.getPool().getFactory());
10009 D.AddTypeInfo(DeclaratorChunk::getReference(0, IdentLoc, /*lvalue*/false),
10010 EmptyAttrs, IdentLoc);
10011 Decl *Var = ActOnDeclarator(S, D);
10012 cast<VarDecl>(Var)->setCXXForRangeDecl(true);
10013 FinalizeDeclaration(Var);
10014 return ActOnDeclStmt(FinalizeDeclaratorGroup(S, DS, Var), IdentLoc,
10015 AttrEnd.isValid() ? AttrEnd : IdentLoc);
10018 void Sema::CheckCompleteVariableDeclaration(VarDecl *var) {
10019 if (var->isInvalidDecl()) return;
10021 // In Objective-C, don't allow jumps past the implicit initialization of a
10022 // local retaining variable.
10023 if (getLangOpts().ObjC1 &&
10024 var->hasLocalStorage()) {
10025 switch (var->getType().getObjCLifetime()) {
10026 case Qualifiers::OCL_None:
10027 case Qualifiers::OCL_ExplicitNone:
10028 case Qualifiers::OCL_Autoreleasing:
10031 case Qualifiers::OCL_Weak:
10032 case Qualifiers::OCL_Strong:
10033 getCurFunction()->setHasBranchProtectedScope();
10038 // Warn about externally-visible variables being defined without a
10039 // prior declaration. We only want to do this for global
10040 // declarations, but we also specifically need to avoid doing it for
10041 // class members because the linkage of an anonymous class can
10042 // change if it's later given a typedef name.
10043 if (var->isThisDeclarationADefinition() &&
10044 var->getDeclContext()->getRedeclContext()->isFileContext() &&
10045 var->isExternallyVisible() && var->hasLinkage() &&
10046 !getDiagnostics().isIgnored(diag::warn_missing_variable_declarations,
10047 var->getLocation())) {
10048 // Find a previous declaration that's not a definition.
10049 VarDecl *prev = var->getPreviousDecl();
10050 while (prev && prev->isThisDeclarationADefinition())
10051 prev = prev->getPreviousDecl();
10054 Diag(var->getLocation(), diag::warn_missing_variable_declarations) << var;
10057 if (var->getTLSKind() == VarDecl::TLS_Static) {
10058 const Expr *Culprit;
10059 if (var->getType().isDestructedType()) {
10060 // GNU C++98 edits for __thread, [basic.start.term]p3:
10061 // The type of an object with thread storage duration shall not
10062 // have a non-trivial destructor.
10063 Diag(var->getLocation(), diag::err_thread_nontrivial_dtor);
10064 if (getLangOpts().CPlusPlus11)
10065 Diag(var->getLocation(), diag::note_use_thread_local);
10066 } else if (getLangOpts().CPlusPlus && var->hasInit() &&
10067 !var->getInit()->isConstantInitializer(
10068 Context, var->getType()->isReferenceType(), &Culprit)) {
10069 // GNU C++98 edits for __thread, [basic.start.init]p4:
10070 // An object of thread storage duration shall not require dynamic
10072 // FIXME: Need strict checking here.
10073 Diag(Culprit->getExprLoc(), diag::err_thread_dynamic_init)
10074 << Culprit->getSourceRange();
10075 if (getLangOpts().CPlusPlus11)
10076 Diag(var->getLocation(), diag::note_use_thread_local);
10080 // Apply section attributes and pragmas to global variables.
10081 bool GlobalStorage = var->hasGlobalStorage();
10082 if (GlobalStorage && var->isThisDeclarationADefinition() &&
10083 ActiveTemplateInstantiations.empty()) {
10084 PragmaStack<StringLiteral *> *Stack = nullptr;
10085 int SectionFlags = ASTContext::PSF_Implicit | ASTContext::PSF_Read;
10086 if (var->getType().isConstQualified())
10087 Stack = &ConstSegStack;
10088 else if (!var->getInit()) {
10089 Stack = &BSSSegStack;
10090 SectionFlags |= ASTContext::PSF_Write;
10092 Stack = &DataSegStack;
10093 SectionFlags |= ASTContext::PSF_Write;
10095 if (Stack->CurrentValue && !var->hasAttr<SectionAttr>()) {
10096 var->addAttr(SectionAttr::CreateImplicit(
10097 Context, SectionAttr::Declspec_allocate,
10098 Stack->CurrentValue->getString(), Stack->CurrentPragmaLocation));
10100 if (const SectionAttr *SA = var->getAttr<SectionAttr>())
10101 if (UnifySection(SA->getName(), SectionFlags, var))
10102 var->dropAttr<SectionAttr>();
10104 // Apply the init_seg attribute if this has an initializer. If the
10105 // initializer turns out to not be dynamic, we'll end up ignoring this
10107 if (CurInitSeg && var->getInit())
10108 var->addAttr(InitSegAttr::CreateImplicit(Context, CurInitSeg->getString(),
10112 // All the following checks are C++ only.
10113 if (!getLangOpts().CPlusPlus) return;
10115 QualType type = var->getType();
10116 if (type->isDependentType()) return;
10118 // __block variables might require us to capture a copy-initializer.
10119 if (var->hasAttr<BlocksAttr>()) {
10120 // It's currently invalid to ever have a __block variable with an
10121 // array type; should we diagnose that here?
10123 // Regardless, we don't want to ignore array nesting when
10124 // constructing this copy.
10125 if (type->isStructureOrClassType()) {
10126 EnterExpressionEvaluationContext scope(*this, PotentiallyEvaluated);
10127 SourceLocation poi = var->getLocation();
10128 Expr *varRef =new (Context) DeclRefExpr(var, false, type, VK_LValue, poi);
10130 = PerformMoveOrCopyInitialization(
10131 InitializedEntity::InitializeBlock(poi, type, false),
10132 var, var->getType(), varRef, /*AllowNRVO=*/true);
10133 if (!result.isInvalid()) {
10134 result = MaybeCreateExprWithCleanups(result);
10135 Expr *init = result.getAs<Expr>();
10136 Context.setBlockVarCopyInits(var, init);
10141 Expr *Init = var->getInit();
10142 bool IsGlobal = GlobalStorage && !var->isStaticLocal();
10143 QualType baseType = Context.getBaseElementType(type);
10145 if (!var->getDeclContext()->isDependentContext() &&
10146 Init && !Init->isValueDependent()) {
10147 if (IsGlobal && !var->isConstexpr() &&
10148 !getDiagnostics().isIgnored(diag::warn_global_constructor,
10149 var->getLocation())) {
10150 // Warn about globals which don't have a constant initializer. Don't
10151 // warn about globals with a non-trivial destructor because we already
10152 // warned about them.
10153 CXXRecordDecl *RD = baseType->getAsCXXRecordDecl();
10154 if (!(RD && !RD->hasTrivialDestructor()) &&
10155 !Init->isConstantInitializer(Context, baseType->isReferenceType()))
10156 Diag(var->getLocation(), diag::warn_global_constructor)
10157 << Init->getSourceRange();
10160 if (var->isConstexpr()) {
10161 SmallVector<PartialDiagnosticAt, 8> Notes;
10162 if (!var->evaluateValue(Notes) || !var->isInitICE()) {
10163 SourceLocation DiagLoc = var->getLocation();
10164 // If the note doesn't add any useful information other than a source
10165 // location, fold it into the primary diagnostic.
10166 if (Notes.size() == 1 && Notes[0].second.getDiagID() ==
10167 diag::note_invalid_subexpr_in_const_expr) {
10168 DiagLoc = Notes[0].first;
10171 Diag(DiagLoc, diag::err_constexpr_var_requires_const_init)
10172 << var << Init->getSourceRange();
10173 for (unsigned I = 0, N = Notes.size(); I != N; ++I)
10174 Diag(Notes[I].first, Notes[I].second);
10176 } else if (var->isUsableInConstantExpressions(Context)) {
10177 // Check whether the initializer of a const variable of integral or
10178 // enumeration type is an ICE now, since we can't tell whether it was
10179 // initialized by a constant expression if we check later.
10180 var->checkInitIsICE();
10184 // Require the destructor.
10185 if (const RecordType *recordType = baseType->getAs<RecordType>())
10186 FinalizeVarWithDestructor(var, recordType);
10189 /// \brief Determines if a variable's alignment is dependent.
10190 static bool hasDependentAlignment(VarDecl *VD) {
10191 if (VD->getType()->isDependentType())
10193 for (auto *I : VD->specific_attrs<AlignedAttr>())
10194 if (I->isAlignmentDependent())
10199 /// FinalizeDeclaration - called by ParseDeclarationAfterDeclarator to perform
10200 /// any semantic actions necessary after any initializer has been attached.
10202 Sema::FinalizeDeclaration(Decl *ThisDecl) {
10203 // Note that we are no longer parsing the initializer for this declaration.
10204 ParsingInitForAutoVars.erase(ThisDecl);
10206 VarDecl *VD = dyn_cast_or_null<VarDecl>(ThisDecl);
10210 checkAttributesAfterMerging(*this, *VD);
10212 // Perform TLS alignment check here after attributes attached to the variable
10213 // which may affect the alignment have been processed. Only perform the check
10214 // if the target has a maximum TLS alignment (zero means no constraints).
10215 if (unsigned MaxAlign = Context.getTargetInfo().getMaxTLSAlign()) {
10216 // Protect the check so that it's not performed on dependent types and
10217 // dependent alignments (we can't determine the alignment in that case).
10218 if (VD->getTLSKind() && !hasDependentAlignment(VD)) {
10219 CharUnits MaxAlignChars = Context.toCharUnitsFromBits(MaxAlign);
10220 if (Context.getDeclAlign(VD) > MaxAlignChars) {
10221 Diag(VD->getLocation(), diag::err_tls_var_aligned_over_maximum)
10222 << (unsigned)Context.getDeclAlign(VD).getQuantity() << VD
10223 << (unsigned)MaxAlignChars.getQuantity();
10228 // Static locals inherit dll attributes from their function.
10229 if (VD->isStaticLocal()) {
10230 if (FunctionDecl *FD =
10231 dyn_cast_or_null<FunctionDecl>(VD->getParentFunctionOrMethod())) {
10232 if (Attr *A = getDLLAttr(FD)) {
10233 auto *NewAttr = cast<InheritableAttr>(A->clone(getASTContext()));
10234 NewAttr->setInherited(true);
10235 VD->addAttr(NewAttr);
10240 // Perform check for initializers of device-side global variables.
10241 // CUDA allows empty constructors as initializers (see E.2.3.1, CUDA
10242 // 7.5). CUDA also allows constant initializers for __constant__ and
10243 // __device__ variables.
10244 if (getLangOpts().CUDA && getLangOpts().CUDAIsDevice) {
10245 const Expr *Init = VD->getInit();
10246 const bool IsGlobal = VD->hasGlobalStorage() && !VD->isStaticLocal();
10247 if (Init && IsGlobal &&
10248 (VD->hasAttr<CUDADeviceAttr>() || VD->hasAttr<CUDAConstantAttr>() ||
10249 VD->hasAttr<CUDASharedAttr>())) {
10250 bool AllowedInit = false;
10251 if (const CXXConstructExpr *CE = dyn_cast<CXXConstructExpr>(Init))
10253 isEmptyCudaConstructor(VD->getLocation(), CE->getConstructor());
10254 // We'll allow constant initializers even if it's a non-empty
10255 // constructor according to CUDA rules. This deviates from NVCC,
10256 // but allows us to handle things like constexpr constructors.
10257 if (!AllowedInit &&
10258 (VD->hasAttr<CUDADeviceAttr>() || VD->hasAttr<CUDAConstantAttr>()))
10259 AllowedInit = VD->getInit()->isConstantInitializer(
10260 Context, VD->getType()->isReferenceType());
10262 if (!AllowedInit) {
10263 Diag(VD->getLocation(), VD->hasAttr<CUDASharedAttr>()
10264 ? diag::err_shared_var_init
10265 : diag::err_dynamic_var_init)
10266 << Init->getSourceRange();
10267 VD->setInvalidDecl();
10272 // Grab the dllimport or dllexport attribute off of the VarDecl.
10273 const InheritableAttr *DLLAttr = getDLLAttr(VD);
10275 // Imported static data members cannot be defined out-of-line.
10276 if (const auto *IA = dyn_cast_or_null<DLLImportAttr>(DLLAttr)) {
10277 if (VD->isStaticDataMember() && VD->isOutOfLine() &&
10278 VD->isThisDeclarationADefinition()) {
10279 // We allow definitions of dllimport class template static data members
10281 CXXRecordDecl *Context =
10282 cast<CXXRecordDecl>(VD->getFirstDecl()->getDeclContext());
10283 bool IsClassTemplateMember =
10284 isa<ClassTemplatePartialSpecializationDecl>(Context) ||
10285 Context->getDescribedClassTemplate();
10287 Diag(VD->getLocation(),
10288 IsClassTemplateMember
10289 ? diag::warn_attribute_dllimport_static_field_definition
10290 : diag::err_attribute_dllimport_static_field_definition);
10291 Diag(IA->getLocation(), diag::note_attribute);
10292 if (!IsClassTemplateMember)
10293 VD->setInvalidDecl();
10297 // dllimport/dllexport variables cannot be thread local, their TLS index
10298 // isn't exported with the variable.
10299 if (DLLAttr && VD->getTLSKind()) {
10300 auto *F = dyn_cast_or_null<FunctionDecl>(VD->getParentFunctionOrMethod());
10301 if (F && getDLLAttr(F)) {
10302 assert(VD->isStaticLocal());
10303 // But if this is a static local in a dlimport/dllexport function, the
10304 // function will never be inlined, which means the var would never be
10305 // imported, so having it marked import/export is safe.
10307 Diag(VD->getLocation(), diag::err_attribute_dll_thread_local) << VD
10309 VD->setInvalidDecl();
10313 if (UsedAttr *Attr = VD->getAttr<UsedAttr>()) {
10314 if (!Attr->isInherited() && !VD->isThisDeclarationADefinition()) {
10315 Diag(Attr->getLocation(), diag::warn_attribute_ignored) << Attr;
10316 VD->dropAttr<UsedAttr>();
10320 const DeclContext *DC = VD->getDeclContext();
10321 // If there's a #pragma GCC visibility in scope, and this isn't a class
10322 // member, set the visibility of this variable.
10323 if (DC->getRedeclContext()->isFileContext() && VD->isExternallyVisible())
10324 AddPushedVisibilityAttribute(VD);
10326 // FIXME: Warn on unused templates.
10327 if (VD->isFileVarDecl() && !VD->getDescribedVarTemplate() &&
10328 !isa<VarTemplatePartialSpecializationDecl>(VD))
10329 MarkUnusedFileScopedDecl(VD);
10331 // Now we have parsed the initializer and can update the table of magic
10333 if (!VD->hasAttr<TypeTagForDatatypeAttr>() ||
10334 !VD->getType()->isIntegralOrEnumerationType())
10337 for (const auto *I : ThisDecl->specific_attrs<TypeTagForDatatypeAttr>()) {
10338 const Expr *MagicValueExpr = VD->getInit();
10339 if (!MagicValueExpr) {
10342 llvm::APSInt MagicValueInt;
10343 if (!MagicValueExpr->isIntegerConstantExpr(MagicValueInt, Context)) {
10344 Diag(I->getRange().getBegin(),
10345 diag::err_type_tag_for_datatype_not_ice)
10346 << LangOpts.CPlusPlus << MagicValueExpr->getSourceRange();
10349 if (MagicValueInt.getActiveBits() > 64) {
10350 Diag(I->getRange().getBegin(),
10351 diag::err_type_tag_for_datatype_too_large)
10352 << LangOpts.CPlusPlus << MagicValueExpr->getSourceRange();
10355 uint64_t MagicValue = MagicValueInt.getZExtValue();
10356 RegisterTypeTagForDatatype(I->getArgumentKind(),
10358 I->getMatchingCType(),
10359 I->getLayoutCompatible(),
10360 I->getMustBeNull());
10364 Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS,
10365 ArrayRef<Decl *> Group) {
10366 SmallVector<Decl*, 8> Decls;
10368 if (DS.isTypeSpecOwned())
10369 Decls.push_back(DS.getRepAsDecl());
10371 DeclaratorDecl *FirstDeclaratorInGroup = nullptr;
10372 for (unsigned i = 0, e = Group.size(); i != e; ++i)
10373 if (Decl *D = Group[i]) {
10374 if (DeclaratorDecl *DD = dyn_cast<DeclaratorDecl>(D))
10375 if (!FirstDeclaratorInGroup)
10376 FirstDeclaratorInGroup = DD;
10377 Decls.push_back(D);
10380 if (DeclSpec::isDeclRep(DS.getTypeSpecType())) {
10381 if (TagDecl *Tag = dyn_cast_or_null<TagDecl>(DS.getRepAsDecl())) {
10382 handleTagNumbering(Tag, S);
10383 if (FirstDeclaratorInGroup && !Tag->hasNameForLinkage() &&
10384 getLangOpts().CPlusPlus)
10385 Context.addDeclaratorForUnnamedTagDecl(Tag, FirstDeclaratorInGroup);
10389 return BuildDeclaratorGroup(Decls, DS.containsPlaceholderType());
10392 /// BuildDeclaratorGroup - convert a list of declarations into a declaration
10393 /// group, performing any necessary semantic checking.
10394 Sema::DeclGroupPtrTy
10395 Sema::BuildDeclaratorGroup(MutableArrayRef<Decl *> Group,
10396 bool TypeMayContainAuto) {
10397 // C++0x [dcl.spec.auto]p7:
10398 // If the type deduced for the template parameter U is not the same in each
10399 // deduction, the program is ill-formed.
10400 // FIXME: When initializer-list support is added, a distinction is needed
10401 // between the deduced type U and the deduced type which 'auto' stands for.
10402 // auto a = 0, b = { 1, 2, 3 };
10403 // is legal because the deduced type U is 'int' in both cases.
10404 if (TypeMayContainAuto && Group.size() > 1) {
10406 CanQualType DeducedCanon;
10407 VarDecl *DeducedDecl = nullptr;
10408 for (unsigned i = 0, e = Group.size(); i != e; ++i) {
10409 if (VarDecl *D = dyn_cast<VarDecl>(Group[i])) {
10410 AutoType *AT = D->getType()->getContainedAutoType();
10411 // Don't reissue diagnostics when instantiating a template.
10412 if (AT && D->isInvalidDecl())
10414 QualType U = AT ? AT->getDeducedType() : QualType();
10416 CanQualType UCanon = Context.getCanonicalType(U);
10417 if (Deduced.isNull()) {
10419 DeducedCanon = UCanon;
10421 } else if (DeducedCanon != UCanon) {
10422 Diag(D->getTypeSourceInfo()->getTypeLoc().getBeginLoc(),
10423 diag::err_auto_different_deductions)
10424 << (unsigned)AT->getKeyword()
10425 << Deduced << DeducedDecl->getDeclName()
10426 << U << D->getDeclName()
10427 << DeducedDecl->getInit()->getSourceRange()
10428 << D->getInit()->getSourceRange();
10429 D->setInvalidDecl();
10437 ActOnDocumentableDecls(Group);
10439 return DeclGroupPtrTy::make(
10440 DeclGroupRef::Create(Context, Group.data(), Group.size()));
10443 void Sema::ActOnDocumentableDecl(Decl *D) {
10444 ActOnDocumentableDecls(D);
10447 void Sema::ActOnDocumentableDecls(ArrayRef<Decl *> Group) {
10448 // Don't parse the comment if Doxygen diagnostics are ignored.
10449 if (Group.empty() || !Group[0])
10452 if (Diags.isIgnored(diag::warn_doc_param_not_found,
10453 Group[0]->getLocation()) &&
10454 Diags.isIgnored(diag::warn_unknown_comment_command_name,
10455 Group[0]->getLocation()))
10458 if (Group.size() >= 2) {
10459 // This is a decl group. Normally it will contain only declarations
10460 // produced from declarator list. But in case we have any definitions or
10461 // additional declaration references:
10462 // 'typedef struct S {} S;'
10463 // 'typedef struct S *S;'
10465 // FinalizeDeclaratorGroup adds these as separate declarations.
10466 Decl *MaybeTagDecl = Group[0];
10467 if (MaybeTagDecl && isa<TagDecl>(MaybeTagDecl)) {
10468 Group = Group.slice(1);
10472 // See if there are any new comments that are not attached to a decl.
10473 ArrayRef<RawComment *> Comments = Context.getRawCommentList().getComments();
10474 if (!Comments.empty() &&
10475 !Comments.back()->isAttached()) {
10476 // There is at least one comment that not attached to a decl.
10477 // Maybe it should be attached to one of these decls?
10479 // Note that this way we pick up not only comments that precede the
10480 // declaration, but also comments that *follow* the declaration -- thanks to
10481 // the lookahead in the lexer: we've consumed the semicolon and looked
10482 // ahead through comments.
10483 for (unsigned i = 0, e = Group.size(); i != e; ++i)
10484 Context.getCommentForDecl(Group[i], &PP);
10488 /// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator()
10489 /// to introduce parameters into function prototype scope.
10490 Decl *Sema::ActOnParamDeclarator(Scope *S, Declarator &D) {
10491 const DeclSpec &DS = D.getDeclSpec();
10493 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'.
10495 // C++03 [dcl.stc]p2 also permits 'auto'.
10496 StorageClass SC = SC_None;
10497 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) {
10499 } else if (getLangOpts().CPlusPlus &&
10500 DS.getStorageClassSpec() == DeclSpec::SCS_auto) {
10502 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) {
10503 Diag(DS.getStorageClassSpecLoc(),
10504 diag::err_invalid_storage_class_in_func_decl);
10505 D.getMutableDeclSpec().ClearStorageClassSpecs();
10508 if (DeclSpec::TSCS TSCS = DS.getThreadStorageClassSpec())
10509 Diag(DS.getThreadStorageClassSpecLoc(), diag::err_invalid_thread)
10510 << DeclSpec::getSpecifierName(TSCS);
10511 if (DS.isConstexprSpecified())
10512 Diag(DS.getConstexprSpecLoc(), diag::err_invalid_constexpr)
10514 if (DS.isConceptSpecified())
10515 Diag(DS.getConceptSpecLoc(), diag::err_concept_wrong_decl_kind);
10517 DiagnoseFunctionSpecifiers(DS);
10519 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S);
10520 QualType parmDeclType = TInfo->getType();
10522 if (getLangOpts().CPlusPlus) {
10523 // Check that there are no default arguments inside the type of this
10525 CheckExtraCXXDefaultArguments(D);
10527 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1).
10528 if (D.getCXXScopeSpec().isSet()) {
10529 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator)
10530 << D.getCXXScopeSpec().getRange();
10531 D.getCXXScopeSpec().clear();
10535 // Ensure we have a valid name
10536 IdentifierInfo *II = nullptr;
10538 II = D.getIdentifier();
10540 Diag(D.getIdentifierLoc(), diag::err_bad_parameter_name)
10541 << GetNameForDeclarator(D).getName();
10542 D.setInvalidType(true);
10546 // Check for redeclaration of parameters, e.g. int foo(int x, int x);
10548 LookupResult R(*this, II, D.getIdentifierLoc(), LookupOrdinaryName,
10551 if (R.isSingleResult()) {
10552 NamedDecl *PrevDecl = R.getFoundDecl();
10553 if (PrevDecl->isTemplateParameter()) {
10554 // Maybe we will complain about the shadowed template parameter.
10555 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl);
10556 // Just pretend that we didn't see the previous declaration.
10557 PrevDecl = nullptr;
10558 } else if (S->isDeclScope(PrevDecl)) {
10559 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II;
10560 Diag(PrevDecl->getLocation(), diag::note_previous_declaration);
10562 // Recover by removing the name
10564 D.SetIdentifier(nullptr, D.getIdentifierLoc());
10565 D.setInvalidType(true);
10570 // Temporarily put parameter variables in the translation unit, not
10571 // the enclosing context. This prevents them from accidentally
10572 // looking like class members in C++.
10573 ParmVarDecl *New = CheckParameter(Context.getTranslationUnitDecl(),
10575 D.getIdentifierLoc(), II,
10576 parmDeclType, TInfo,
10579 if (D.isInvalidType())
10580 New->setInvalidDecl();
10582 assert(S->isFunctionPrototypeScope());
10583 assert(S->getFunctionPrototypeDepth() >= 1);
10584 New->setScopeInfo(S->getFunctionPrototypeDepth() - 1,
10585 S->getNextFunctionPrototypeIndex());
10587 // Add the parameter declaration into this scope.
10590 IdResolver.AddDecl(New);
10592 ProcessDeclAttributes(S, New, D);
10594 if (D.getDeclSpec().isModulePrivateSpecified())
10595 Diag(New->getLocation(), diag::err_module_private_local)
10596 << 1 << New->getDeclName()
10597 << SourceRange(D.getDeclSpec().getModulePrivateSpecLoc())
10598 << FixItHint::CreateRemoval(D.getDeclSpec().getModulePrivateSpecLoc());
10600 if (New->hasAttr<BlocksAttr>()) {
10601 Diag(New->getLocation(), diag::err_block_on_nonlocal);
10606 /// \brief Synthesizes a variable for a parameter arising from a
10608 ParmVarDecl *Sema::BuildParmVarDeclForTypedef(DeclContext *DC,
10609 SourceLocation Loc,
10611 /* FIXME: setting StartLoc == Loc.
10612 Would it be worth to modify callers so as to provide proper source
10613 location for the unnamed parameters, embedding the parameter's type? */
10614 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, Loc, Loc, nullptr,
10615 T, Context.getTrivialTypeSourceInfo(T, Loc),
10617 Param->setImplicit();
10621 void Sema::DiagnoseUnusedParameters(ParmVarDecl * const *Param,
10622 ParmVarDecl * const *ParamEnd) {
10623 // Don't diagnose unused-parameter errors in template instantiations; we
10624 // will already have done so in the template itself.
10625 if (!ActiveTemplateInstantiations.empty())
10628 for (; Param != ParamEnd; ++Param) {
10629 if (!(*Param)->isReferenced() && (*Param)->getDeclName() &&
10630 !(*Param)->hasAttr<UnusedAttr>()) {
10631 Diag((*Param)->getLocation(), diag::warn_unused_parameter)
10632 << (*Param)->getDeclName();
10637 void Sema::DiagnoseSizeOfParametersAndReturnValue(ParmVarDecl * const *Param,
10638 ParmVarDecl * const *ParamEnd,
10641 if (LangOpts.NumLargeByValueCopy == 0) // No check.
10644 // Warn if the return value is pass-by-value and larger than the specified
10646 if (!ReturnTy->isDependentType() && ReturnTy.isPODType(Context)) {
10647 unsigned Size = Context.getTypeSizeInChars(ReturnTy).getQuantity();
10648 if (Size > LangOpts.NumLargeByValueCopy)
10649 Diag(D->getLocation(), diag::warn_return_value_size)
10650 << D->getDeclName() << Size;
10653 // Warn if any parameter is pass-by-value and larger than the specified
10655 for (; Param != ParamEnd; ++Param) {
10656 QualType T = (*Param)->getType();
10657 if (T->isDependentType() || !T.isPODType(Context))
10659 unsigned Size = Context.getTypeSizeInChars(T).getQuantity();
10660 if (Size > LangOpts.NumLargeByValueCopy)
10661 Diag((*Param)->getLocation(), diag::warn_parameter_size)
10662 << (*Param)->getDeclName() << Size;
10666 ParmVarDecl *Sema::CheckParameter(DeclContext *DC, SourceLocation StartLoc,
10667 SourceLocation NameLoc, IdentifierInfo *Name,
10668 QualType T, TypeSourceInfo *TSInfo,
10670 // In ARC, infer a lifetime qualifier for appropriate parameter types.
10671 if (getLangOpts().ObjCAutoRefCount &&
10672 T.getObjCLifetime() == Qualifiers::OCL_None &&
10673 T->isObjCLifetimeType()) {
10675 Qualifiers::ObjCLifetime lifetime;
10677 // Special cases for arrays:
10678 // - if it's const, use __unsafe_unretained
10679 // - otherwise, it's an error
10680 if (T->isArrayType()) {
10681 if (!T.isConstQualified()) {
10682 DelayedDiagnostics.add(
10683 sema::DelayedDiagnostic::makeForbiddenType(
10684 NameLoc, diag::err_arc_array_param_no_ownership, T, false));
10686 lifetime = Qualifiers::OCL_ExplicitNone;
10688 lifetime = T->getObjCARCImplicitLifetime();
10690 T = Context.getLifetimeQualifiedType(T, lifetime);
10693 ParmVarDecl *New = ParmVarDecl::Create(Context, DC, StartLoc, NameLoc, Name,
10694 Context.getAdjustedParameterType(T),
10695 TSInfo, SC, nullptr);
10697 // Parameters can not be abstract class types.
10698 // For record types, this is done by the AbstractClassUsageDiagnoser once
10699 // the class has been completely parsed.
10700 if (!CurContext->isRecord() &&
10701 RequireNonAbstractType(NameLoc, T, diag::err_abstract_type_in_decl,
10702 AbstractParamType))
10703 New->setInvalidDecl();
10705 // Parameter declarators cannot be interface types. All ObjC objects are
10706 // passed by reference.
10707 if (T->isObjCObjectType()) {
10708 SourceLocation TypeEndLoc = TSInfo->getTypeLoc().getLocEnd();
10710 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T
10711 << FixItHint::CreateInsertion(TypeEndLoc, "*");
10712 T = Context.getObjCObjectPointerType(T);
10716 // ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage
10717 // duration shall not be qualified by an address-space qualifier."
10718 // Since all parameters have automatic store duration, they can not have
10719 // an address space.
10720 if (T.getAddressSpace() != 0) {
10721 // OpenCL allows function arguments declared to be an array of a type
10722 // to be qualified with an address space.
10723 if (!(getLangOpts().OpenCL && T->isArrayType())) {
10724 Diag(NameLoc, diag::err_arg_with_address_space);
10725 New->setInvalidDecl();
10732 void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D,
10733 SourceLocation LocAfterDecls) {
10734 DeclaratorChunk::FunctionTypeInfo &FTI = D.getFunctionTypeInfo();
10736 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared'
10737 // for a K&R function.
10738 if (!FTI.hasPrototype) {
10739 for (int i = FTI.NumParams; i != 0; /* decrement in loop */) {
10741 if (FTI.Params[i].Param == nullptr) {
10742 SmallString<256> Code;
10743 llvm::raw_svector_ostream(Code)
10744 << " int " << FTI.Params[i].Ident->getName() << ";\n";
10745 Diag(FTI.Params[i].IdentLoc, diag::ext_param_not_declared)
10746 << FTI.Params[i].Ident
10747 << FixItHint::CreateInsertion(LocAfterDecls, Code);
10749 // Implicitly declare the argument as type 'int' for lack of a better
10751 AttributeFactory attrs;
10752 DeclSpec DS(attrs);
10753 const char* PrevSpec; // unused
10754 unsigned DiagID; // unused
10755 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.Params[i].IdentLoc, PrevSpec,
10756 DiagID, Context.getPrintingPolicy());
10757 // Use the identifier location for the type source range.
10758 DS.SetRangeStart(FTI.Params[i].IdentLoc);
10759 DS.SetRangeEnd(FTI.Params[i].IdentLoc);
10760 Declarator ParamD(DS, Declarator::KNRTypeListContext);
10761 ParamD.SetIdentifier(FTI.Params[i].Ident, FTI.Params[i].IdentLoc);
10762 FTI.Params[i].Param = ActOnParamDeclarator(S, ParamD);
10769 Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, Declarator &D,
10770 MultiTemplateParamsArg TemplateParameterLists,
10771 SkipBodyInfo *SkipBody) {
10772 assert(getCurFunctionDecl() == nullptr && "Function parsing confused");
10773 assert(D.isFunctionDeclarator() && "Not a function declarator!");
10774 Scope *ParentScope = FnBodyScope->getParent();
10776 D.setFunctionDefinitionKind(FDK_Definition);
10777 Decl *DP = HandleDeclarator(ParentScope, D, TemplateParameterLists);
10778 return ActOnStartOfFunctionDef(FnBodyScope, DP, SkipBody);
10781 void Sema::ActOnFinishInlineMethodDef(CXXMethodDecl *D) {
10782 Consumer.HandleInlineMethodDefinition(D);
10785 static bool ShouldWarnAboutMissingPrototype(const FunctionDecl *FD,
10786 const FunctionDecl*& PossibleZeroParamPrototype) {
10787 // Don't warn about invalid declarations.
10788 if (FD->isInvalidDecl())
10791 // Or declarations that aren't global.
10792 if (!FD->isGlobal())
10795 // Don't warn about C++ member functions.
10796 if (isa<CXXMethodDecl>(FD))
10799 // Don't warn about 'main'.
10803 // Don't warn about inline functions.
10804 if (FD->isInlined())
10807 // Don't warn about function templates.
10808 if (FD->getDescribedFunctionTemplate())
10811 // Don't warn about function template specializations.
10812 if (FD->isFunctionTemplateSpecialization())
10815 // Don't warn for OpenCL kernels.
10816 if (FD->hasAttr<OpenCLKernelAttr>())
10819 // Don't warn on explicitly deleted functions.
10820 if (FD->isDeleted())
10823 bool MissingPrototype = true;
10824 for (const FunctionDecl *Prev = FD->getPreviousDecl();
10825 Prev; Prev = Prev->getPreviousDecl()) {
10826 // Ignore any declarations that occur in function or method
10827 // scope, because they aren't visible from the header.
10828 if (Prev->getLexicalDeclContext()->isFunctionOrMethod())
10831 MissingPrototype = !Prev->getType()->isFunctionProtoType();
10832 if (FD->getNumParams() == 0)
10833 PossibleZeroParamPrototype = Prev;
10837 return MissingPrototype;
10841 Sema::CheckForFunctionRedefinition(FunctionDecl *FD,
10842 const FunctionDecl *EffectiveDefinition,
10843 SkipBodyInfo *SkipBody) {
10844 // Don't complain if we're in GNU89 mode and the previous definition
10845 // was an extern inline function.
10846 const FunctionDecl *Definition = EffectiveDefinition;
10848 if (!FD->isDefined(Definition))
10851 if (canRedefineFunction(Definition, getLangOpts()))
10854 // If we don't have a visible definition of the function, and it's inline or
10855 // a template, skip the new definition.
10856 if (SkipBody && !hasVisibleDefinition(Definition) &&
10857 (Definition->getFormalLinkage() == InternalLinkage ||
10858 Definition->isInlined() ||
10859 Definition->getDescribedFunctionTemplate() ||
10860 Definition->getNumTemplateParameterLists())) {
10861 SkipBody->ShouldSkip = true;
10862 if (auto *TD = Definition->getDescribedFunctionTemplate())
10863 makeMergedDefinitionVisible(TD, FD->getLocation());
10865 makeMergedDefinitionVisible(const_cast<FunctionDecl*>(Definition),
10866 FD->getLocation());
10870 if (getLangOpts().GNUMode && Definition->isInlineSpecified() &&
10871 Definition->getStorageClass() == SC_Extern)
10872 Diag(FD->getLocation(), diag::err_redefinition_extern_inline)
10873 << FD->getDeclName() << getLangOpts().CPlusPlus;
10875 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName();
10877 Diag(Definition->getLocation(), diag::note_previous_definition);
10878 FD->setInvalidDecl();
10881 static void RebuildLambdaScopeInfo(CXXMethodDecl *CallOperator,
10883 CXXRecordDecl *const LambdaClass = CallOperator->getParent();
10885 LambdaScopeInfo *LSI = S.PushLambdaScope();
10886 LSI->CallOperator = CallOperator;
10887 LSI->Lambda = LambdaClass;
10888 LSI->ReturnType = CallOperator->getReturnType();
10889 const LambdaCaptureDefault LCD = LambdaClass->getLambdaCaptureDefault();
10891 if (LCD == LCD_None)
10892 LSI->ImpCaptureStyle = CapturingScopeInfo::ImpCap_None;
10893 else if (LCD == LCD_ByCopy)
10894 LSI->ImpCaptureStyle = CapturingScopeInfo::ImpCap_LambdaByval;
10895 else if (LCD == LCD_ByRef)
10896 LSI->ImpCaptureStyle = CapturingScopeInfo::ImpCap_LambdaByref;
10897 DeclarationNameInfo DNI = CallOperator->getNameInfo();
10899 LSI->IntroducerRange = DNI.getCXXOperatorNameRange();
10900 LSI->Mutable = !CallOperator->isConst();
10902 // Add the captures to the LSI so they can be noted as already
10903 // captured within tryCaptureVar.
10904 auto I = LambdaClass->field_begin();
10905 for (const auto &C : LambdaClass->captures()) {
10906 if (C.capturesVariable()) {
10907 VarDecl *VD = C.getCapturedVar();
10908 if (VD->isInitCapture())
10909 S.CurrentInstantiationScope->InstantiatedLocal(VD, VD);
10910 QualType CaptureType = VD->getType();
10911 const bool ByRef = C.getCaptureKind() == LCK_ByRef;
10912 LSI->addCapture(VD, /*IsBlock*/false, ByRef,
10913 /*RefersToEnclosingVariableOrCapture*/true, C.getLocation(),
10914 /*EllipsisLoc*/C.isPackExpansion()
10915 ? C.getEllipsisLoc() : SourceLocation(),
10916 CaptureType, /*Expr*/ nullptr);
10918 } else if (C.capturesThis()) {
10919 LSI->addThisCapture(/*Nested*/ false, C.getLocation(),
10920 S.getCurrentThisType(), /*Expr*/ nullptr);
10922 LSI->addVLATypeCapture(C.getLocation(), I->getType());
10928 Decl *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, Decl *D,
10929 SkipBodyInfo *SkipBody) {
10930 // Clear the last template instantiation error context.
10931 LastTemplateInstantiationErrorContext = ActiveTemplateInstantiation();
10935 FunctionDecl *FD = nullptr;
10937 if (FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(D))
10938 FD = FunTmpl->getTemplatedDecl();
10940 FD = cast<FunctionDecl>(D);
10942 // See if this is a redefinition.
10943 if (!FD->isLateTemplateParsed()) {
10944 CheckForFunctionRedefinition(FD, nullptr, SkipBody);
10946 // If we're skipping the body, we're done. Don't enter the scope.
10947 if (SkipBody && SkipBody->ShouldSkip)
10951 // If we are instantiating a generic lambda call operator, push
10952 // a LambdaScopeInfo onto the function stack. But use the information
10953 // that's already been calculated (ActOnLambdaExpr) to prime the current
10954 // LambdaScopeInfo.
10955 // When the template operator is being specialized, the LambdaScopeInfo,
10956 // has to be properly restored so that tryCaptureVariable doesn't try
10957 // and capture any new variables. In addition when calculating potential
10958 // captures during transformation of nested lambdas, it is necessary to
10959 // have the LSI properly restored.
10960 if (isGenericLambdaCallOperatorSpecialization(FD)) {
10961 assert(ActiveTemplateInstantiations.size() &&
10962 "There should be an active template instantiation on the stack "
10963 "when instantiating a generic lambda!");
10964 RebuildLambdaScopeInfo(cast<CXXMethodDecl>(D), *this);
10967 // Enter a new function scope
10968 PushFunctionScope();
10970 // Builtin functions cannot be defined.
10971 if (unsigned BuiltinID = FD->getBuiltinID()) {
10972 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID) &&
10973 !Context.BuiltinInfo.isPredefinedRuntimeFunction(BuiltinID)) {
10974 Diag(FD->getLocation(), diag::err_builtin_definition) << FD;
10975 FD->setInvalidDecl();
10979 // The return type of a function definition must be complete
10980 // (C99 6.9.1p3, C++ [dcl.fct]p6).
10981 QualType ResultType = FD->getReturnType();
10982 if (!ResultType->isDependentType() && !ResultType->isVoidType() &&
10983 !FD->isInvalidDecl() &&
10984 RequireCompleteType(FD->getLocation(), ResultType,
10985 diag::err_func_def_incomplete_result))
10986 FD->setInvalidDecl();
10989 PushDeclContext(FnBodyScope, FD);
10991 // Check the validity of our function parameters
10992 CheckParmsForFunctionDef(FD->param_begin(), FD->param_end(),
10993 /*CheckParameterNames=*/true);
10995 // Introduce our parameters into the function scope
10996 for (auto Param : FD->params()) {
10997 Param->setOwningFunction(FD);
10999 // If this has an identifier, add it to the scope stack.
11000 if (Param->getIdentifier() && FnBodyScope) {
11001 CheckShadow(FnBodyScope, Param);
11003 PushOnScopeChains(Param, FnBodyScope);
11007 // If we had any tags defined in the function prototype,
11008 // introduce them into the function scope.
11010 for (ArrayRef<NamedDecl *>::iterator
11011 I = FD->getDeclsInPrototypeScope().begin(),
11012 E = FD->getDeclsInPrototypeScope().end();
11016 // Some of these decls (like enums) may have been pinned to the
11017 // translation unit for lack of a real context earlier. If so, remove
11018 // from the translation unit and reattach to the current context.
11019 if (D->getLexicalDeclContext() == Context.getTranslationUnitDecl()) {
11020 // Is the decl actually in the context?
11021 if (Context.getTranslationUnitDecl()->containsDecl(D))
11022 Context.getTranslationUnitDecl()->removeDecl(D);
11023 // Either way, reassign the lexical decl context to our FunctionDecl.
11024 D->setLexicalDeclContext(CurContext);
11027 // If the decl has a non-null name, make accessible in the current scope.
11028 if (!D->getName().empty())
11029 PushOnScopeChains(D, FnBodyScope, /*AddToContext=*/false);
11031 // Similarly, dive into enums and fish their constants out, making them
11032 // accessible in this scope.
11033 if (auto *ED = dyn_cast<EnumDecl>(D)) {
11034 for (auto *EI : ED->enumerators())
11035 PushOnScopeChains(EI, FnBodyScope, /*AddToContext=*/false);
11040 // Ensure that the function's exception specification is instantiated.
11041 if (const FunctionProtoType *FPT = FD->getType()->getAs<FunctionProtoType>())
11042 ResolveExceptionSpec(D->getLocation(), FPT);
11044 // dllimport cannot be applied to non-inline function definitions.
11045 if (FD->hasAttr<DLLImportAttr>() && !FD->isInlined() &&
11046 !FD->isTemplateInstantiation()) {
11047 assert(!FD->hasAttr<DLLExportAttr>());
11048 Diag(FD->getLocation(), diag::err_attribute_dllimport_function_definition);
11049 FD->setInvalidDecl();
11052 // We want to attach documentation to original Decl (which might be
11053 // a function template).
11054 ActOnDocumentableDecl(D);
11055 if (getCurLexicalContext()->isObjCContainer() &&
11056 getCurLexicalContext()->getDeclKind() != Decl::ObjCCategoryImpl &&
11057 getCurLexicalContext()->getDeclKind() != Decl::ObjCImplementation)
11058 Diag(FD->getLocation(), diag::warn_function_def_in_objc_container);
11063 /// \brief Given the set of return statements within a function body,
11064 /// compute the variables that are subject to the named return value
11067 /// Each of the variables that is subject to the named return value
11068 /// optimization will be marked as NRVO variables in the AST, and any
11069 /// return statement that has a marked NRVO variable as its NRVO candidate can
11070 /// use the named return value optimization.
11072 /// This function applies a very simplistic algorithm for NRVO: if every return
11073 /// statement in the scope of a variable has the same NRVO candidate, that
11074 /// candidate is an NRVO variable.
11075 void Sema::computeNRVO(Stmt *Body, FunctionScopeInfo *Scope) {
11076 ReturnStmt **Returns = Scope->Returns.data();
11078 for (unsigned I = 0, E = Scope->Returns.size(); I != E; ++I) {
11079 if (const VarDecl *NRVOCandidate = Returns[I]->getNRVOCandidate()) {
11080 if (!NRVOCandidate->isNRVOVariable())
11081 Returns[I]->setNRVOCandidate(nullptr);
11086 bool Sema::canDelayFunctionBody(const Declarator &D) {
11087 // We can't delay parsing the body of a constexpr function template (yet).
11088 if (D.getDeclSpec().isConstexprSpecified())
11091 // We can't delay parsing the body of a function template with a deduced
11092 // return type (yet).
11093 if (D.getDeclSpec().containsPlaceholderType()) {
11094 // If the placeholder introduces a non-deduced trailing return type,
11095 // we can still delay parsing it.
11096 if (D.getNumTypeObjects()) {
11097 const auto &Outer = D.getTypeObject(D.getNumTypeObjects() - 1);
11098 if (Outer.Kind == DeclaratorChunk::Function &&
11099 Outer.Fun.hasTrailingReturnType()) {
11100 QualType Ty = GetTypeFromParser(Outer.Fun.getTrailingReturnType());
11101 return Ty.isNull() || !Ty->isUndeducedType();
11110 bool Sema::canSkipFunctionBody(Decl *D) {
11111 // We cannot skip the body of a function (or function template) which is
11112 // constexpr, since we may need to evaluate its body in order to parse the
11113 // rest of the file.
11114 // We cannot skip the body of a function with an undeduced return type,
11115 // because any callers of that function need to know the type.
11116 if (const FunctionDecl *FD = D->getAsFunction())
11117 if (FD->isConstexpr() || FD->getReturnType()->isUndeducedType())
11119 return Consumer.shouldSkipFunctionBody(D);
11122 Decl *Sema::ActOnSkippedFunctionBody(Decl *Decl) {
11123 if (FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(Decl))
11124 FD->setHasSkippedBody();
11125 else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(Decl))
11126 MD->setHasSkippedBody();
11127 return ActOnFinishFunctionBody(Decl, nullptr);
11130 Decl *Sema::ActOnFinishFunctionBody(Decl *D, Stmt *BodyArg) {
11131 return ActOnFinishFunctionBody(D, BodyArg, false);
11134 Decl *Sema::ActOnFinishFunctionBody(Decl *dcl, Stmt *Body,
11135 bool IsInstantiation) {
11136 FunctionDecl *FD = dcl ? dcl->getAsFunction() : nullptr;
11138 sema::AnalysisBasedWarnings::Policy WP = AnalysisWarnings.getDefaultPolicy();
11139 sema::AnalysisBasedWarnings::Policy *ActivePolicy = nullptr;
11141 if (getLangOpts().Coroutines && !getCurFunction()->CoroutineStmts.empty())
11142 CheckCompletedCoroutineBody(FD, Body);
11147 if (getLangOpts().CPlusPlus14) {
11148 if (!FD->isInvalidDecl() && Body && !FD->isDependentContext() &&
11149 FD->getReturnType()->isUndeducedType()) {
11150 // If the function has a deduced result type but contains no 'return'
11151 // statements, the result type as written must be exactly 'auto', and
11152 // the deduced result type is 'void'.
11153 if (!FD->getReturnType()->getAs<AutoType>()) {
11154 Diag(dcl->getLocation(), diag::err_auto_fn_no_return_but_not_auto)
11155 << FD->getReturnType();
11156 FD->setInvalidDecl();
11158 // Substitute 'void' for the 'auto' in the type.
11159 TypeLoc ResultType = getReturnTypeLoc(FD);
11160 Context.adjustDeducedFunctionResultType(
11161 FD, SubstAutoType(ResultType.getType(), Context.VoidTy));
11164 } else if (getLangOpts().CPlusPlus11 && isLambdaCallOperator(FD)) {
11165 // In C++11, we don't use 'auto' deduction rules for lambda call
11166 // operators because we don't support return type deduction.
11167 auto *LSI = getCurLambda();
11168 if (LSI->HasImplicitReturnType) {
11169 deduceClosureReturnType(*LSI);
11171 // C++11 [expr.prim.lambda]p4:
11172 // [...] if there are no return statements in the compound-statement
11173 // [the deduced type is] the type void
11175 LSI->ReturnType.isNull() ? Context.VoidTy : LSI->ReturnType;
11177 // Update the return type to the deduced type.
11178 const FunctionProtoType *Proto =
11179 FD->getType()->getAs<FunctionProtoType>();
11180 FD->setType(Context.getFunctionType(RetType, Proto->getParamTypes(),
11181 Proto->getExtProtoInfo()));
11185 // The only way to be included in UndefinedButUsed is if there is an
11186 // ODR use before the definition. Avoid the expensive map lookup if this
11187 // is the first declaration.
11188 if (!FD->isFirstDecl() && FD->getPreviousDecl()->isUsed()) {
11189 if (!FD->isExternallyVisible())
11190 UndefinedButUsed.erase(FD);
11191 else if (FD->isInlined() &&
11192 !LangOpts.GNUInline &&
11193 (!FD->getPreviousDecl()->hasAttr<GNUInlineAttr>()))
11194 UndefinedButUsed.erase(FD);
11197 // If the function implicitly returns zero (like 'main') or is naked,
11198 // don't complain about missing return statements.
11199 if (FD->hasImplicitReturnZero() || FD->hasAttr<NakedAttr>())
11200 WP.disableCheckFallThrough();
11202 // MSVC permits the use of pure specifier (=0) on function definition,
11203 // defined at class scope, warn about this non-standard construct.
11204 if (getLangOpts().MicrosoftExt && FD->isPure() && FD->isCanonicalDecl())
11205 Diag(FD->getLocation(), diag::ext_pure_function_definition);
11207 if (!FD->isInvalidDecl()) {
11208 // Don't diagnose unused parameters of defaulted or deleted functions.
11209 if (!FD->isDeleted() && !FD->isDefaulted())
11210 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end());
11211 DiagnoseSizeOfParametersAndReturnValue(FD->param_begin(), FD->param_end(),
11212 FD->getReturnType(), FD);
11214 // If this is a structor, we need a vtable.
11215 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(FD))
11216 MarkVTableUsed(FD->getLocation(), Constructor->getParent());
11217 else if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(FD))
11218 MarkVTableUsed(FD->getLocation(), Destructor->getParent());
11220 // Try to apply the named return value optimization. We have to check
11221 // if we can do this here because lambdas keep return statements around
11222 // to deduce an implicit return type.
11223 if (getLangOpts().CPlusPlus && FD->getReturnType()->isRecordType() &&
11224 !FD->isDependentContext())
11225 computeNRVO(Body, getCurFunction());
11228 // GNU warning -Wmissing-prototypes:
11229 // Warn if a global function is defined without a previous
11230 // prototype declaration. This warning is issued even if the
11231 // definition itself provides a prototype. The aim is to detect
11232 // global functions that fail to be declared in header files.
11233 const FunctionDecl *PossibleZeroParamPrototype = nullptr;
11234 if (ShouldWarnAboutMissingPrototype(FD, PossibleZeroParamPrototype)) {
11235 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD;
11237 if (PossibleZeroParamPrototype) {
11238 // We found a declaration that is not a prototype,
11239 // but that could be a zero-parameter prototype
11240 if (TypeSourceInfo *TI =
11241 PossibleZeroParamPrototype->getTypeSourceInfo()) {
11242 TypeLoc TL = TI->getTypeLoc();
11243 if (FunctionNoProtoTypeLoc FTL = TL.getAs<FunctionNoProtoTypeLoc>())
11244 Diag(PossibleZeroParamPrototype->getLocation(),
11245 diag::note_declaration_not_a_prototype)
11246 << PossibleZeroParamPrototype
11247 << FixItHint::CreateInsertion(FTL.getRParenLoc(), "void");
11252 if (auto *MD = dyn_cast<CXXMethodDecl>(FD)) {
11253 const CXXMethodDecl *KeyFunction;
11254 if (MD->isOutOfLine() && (MD = MD->getCanonicalDecl()) &&
11256 (KeyFunction = Context.getCurrentKeyFunction(MD->getParent())) &&
11257 MD == KeyFunction->getCanonicalDecl()) {
11258 // Update the key-function state if necessary for this ABI.
11259 if (FD->isInlined() &&
11260 !Context.getTargetInfo().getCXXABI().canKeyFunctionBeInline()) {
11261 Context.setNonKeyFunction(MD);
11263 // If the newly-chosen key function is already defined, then we
11264 // need to mark the vtable as used retroactively.
11265 KeyFunction = Context.getCurrentKeyFunction(MD->getParent());
11266 const FunctionDecl *Definition;
11267 if (KeyFunction && KeyFunction->isDefined(Definition))
11268 MarkVTableUsed(Definition->getLocation(), MD->getParent(), true);
11270 // We just defined they key function; mark the vtable as used.
11271 MarkVTableUsed(FD->getLocation(), MD->getParent(), true);
11276 assert((FD == getCurFunctionDecl() || getCurLambda()->CallOperator == FD) &&
11277 "Function parsing confused");
11278 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) {
11279 assert(MD == getCurMethodDecl() && "Method parsing confused");
11281 if (!MD->isInvalidDecl()) {
11282 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end());
11283 DiagnoseSizeOfParametersAndReturnValue(MD->param_begin(), MD->param_end(),
11284 MD->getReturnType(), MD);
11287 computeNRVO(Body, getCurFunction());
11289 if (getCurFunction()->ObjCShouldCallSuper) {
11290 Diag(MD->getLocEnd(), diag::warn_objc_missing_super_call)
11291 << MD->getSelector().getAsString();
11292 getCurFunction()->ObjCShouldCallSuper = false;
11294 if (getCurFunction()->ObjCWarnForNoDesignatedInitChain) {
11295 const ObjCMethodDecl *InitMethod = nullptr;
11296 bool isDesignated =
11297 MD->isDesignatedInitializerForTheInterface(&InitMethod);
11298 assert(isDesignated && InitMethod);
11299 (void)isDesignated;
11301 auto superIsNSObject = [&](const ObjCMethodDecl *MD) {
11302 auto IFace = MD->getClassInterface();
11305 auto SuperD = IFace->getSuperClass();
11308 return SuperD->getIdentifier() ==
11309 NSAPIObj->getNSClassId(NSAPI::ClassId_NSObject);
11311 // Don't issue this warning for unavailable inits or direct subclasses
11313 if (!MD->isUnavailable() && !superIsNSObject(MD)) {
11314 Diag(MD->getLocation(),
11315 diag::warn_objc_designated_init_missing_super_call);
11316 Diag(InitMethod->getLocation(),
11317 diag::note_objc_designated_init_marked_here);
11319 getCurFunction()->ObjCWarnForNoDesignatedInitChain = false;
11321 if (getCurFunction()->ObjCWarnForNoInitDelegation) {
11322 // Don't issue this warning for unavaialable inits.
11323 if (!MD->isUnavailable())
11324 Diag(MD->getLocation(),
11325 diag::warn_objc_secondary_init_missing_init_call);
11326 getCurFunction()->ObjCWarnForNoInitDelegation = false;
11332 assert(!getCurFunction()->ObjCShouldCallSuper &&
11333 "This should only be set for ObjC methods, which should have been "
11334 "handled in the block above.");
11336 // Verify and clean out per-function state.
11337 if (Body && (!FD || !FD->isDefaulted())) {
11338 // C++ constructors that have function-try-blocks can't have return
11339 // statements in the handlers of that block. (C++ [except.handle]p14)
11341 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body))
11342 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body));
11344 // Verify that gotos and switch cases don't jump into scopes illegally.
11345 if (getCurFunction()->NeedsScopeChecking() &&
11346 !PP.isCodeCompletionEnabled())
11347 DiagnoseInvalidJumps(Body);
11349 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) {
11350 if (!Destructor->getParent()->isDependentType())
11351 CheckDestructor(Destructor);
11353 MarkBaseAndMemberDestructorsReferenced(Destructor->getLocation(),
11354 Destructor->getParent());
11357 // If any errors have occurred, clear out any temporaries that may have
11358 // been leftover. This ensures that these temporaries won't be picked up for
11359 // deletion in some later function.
11360 if (getDiagnostics().hasErrorOccurred() ||
11361 getDiagnostics().getSuppressAllDiagnostics()) {
11362 DiscardCleanupsInEvaluationContext();
11364 if (!getDiagnostics().hasUncompilableErrorOccurred() &&
11365 !isa<FunctionTemplateDecl>(dcl)) {
11366 // Since the body is valid, issue any analysis-based warnings that are
11368 ActivePolicy = &WP;
11371 if (!IsInstantiation && FD && FD->isConstexpr() && !FD->isInvalidDecl() &&
11372 (!CheckConstexprFunctionDecl(FD) ||
11373 !CheckConstexprFunctionBody(FD, Body)))
11374 FD->setInvalidDecl();
11376 if (FD && FD->hasAttr<NakedAttr>()) {
11377 for (const Stmt *S : Body->children()) {
11378 if (!isa<AsmStmt>(S) && !isa<NullStmt>(S)) {
11379 Diag(S->getLocStart(), diag::err_non_asm_stmt_in_naked_function);
11380 Diag(FD->getAttr<NakedAttr>()->getLocation(), diag::note_attribute);
11381 FD->setInvalidDecl();
11387 assert(ExprCleanupObjects.size() ==
11388 ExprEvalContexts.back().NumCleanupObjects &&
11389 "Leftover temporaries in function");
11390 assert(!ExprNeedsCleanups && "Unaccounted cleanups in function");
11391 assert(MaybeODRUseExprs.empty() &&
11392 "Leftover expressions for odr-use checking");
11395 if (!IsInstantiation)
11398 PopFunctionScopeInfo(ActivePolicy, dcl);
11399 // If any errors have occurred, clear out any temporaries that may have
11400 // been leftover. This ensures that these temporaries won't be picked up for
11401 // deletion in some later function.
11402 if (getDiagnostics().hasErrorOccurred()) {
11403 DiscardCleanupsInEvaluationContext();
11409 /// When we finish delayed parsing of an attribute, we must attach it to the
11411 void Sema::ActOnFinishDelayedAttribute(Scope *S, Decl *D,
11412 ParsedAttributes &Attrs) {
11413 // Always attach attributes to the underlying decl.
11414 if (TemplateDecl *TD = dyn_cast<TemplateDecl>(D))
11415 D = TD->getTemplatedDecl();
11416 ProcessDeclAttributeList(S, D, Attrs.getList());
11418 if (CXXMethodDecl *Method = dyn_cast_or_null<CXXMethodDecl>(D))
11419 if (Method->isStatic())
11420 checkThisInStaticMemberFunctionAttributes(Method);
11423 /// ImplicitlyDefineFunction - An undeclared identifier was used in a function
11424 /// call, forming a call to an implicitly defined function (per C99 6.5.1p2).
11425 NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc,
11426 IdentifierInfo &II, Scope *S) {
11427 // Before we produce a declaration for an implicitly defined
11428 // function, see whether there was a locally-scoped declaration of
11429 // this name as a function or variable. If so, use that
11430 // (non-visible) declaration, and complain about it.
11431 if (NamedDecl *ExternCPrev = findLocallyScopedExternCDecl(&II)) {
11432 Diag(Loc, diag::warn_use_out_of_scope_declaration) << ExternCPrev;
11433 Diag(ExternCPrev->getLocation(), diag::note_previous_declaration);
11434 return ExternCPrev;
11437 // Extension in C99. Legal in C90, but warn about it.
11439 if (II.getName().startswith("__builtin_"))
11440 diag_id = diag::warn_builtin_unknown;
11441 else if (getLangOpts().C99)
11442 diag_id = diag::ext_implicit_function_decl;
11444 diag_id = diag::warn_implicit_function_decl;
11445 Diag(Loc, diag_id) << &II;
11447 // Because typo correction is expensive, only do it if the implicit
11448 // function declaration is going to be treated as an error.
11449 if (Diags.getDiagnosticLevel(diag_id, Loc) >= DiagnosticsEngine::Error) {
11450 TypoCorrection Corrected;
11452 (Corrected = CorrectTypo(
11453 DeclarationNameInfo(&II, Loc), LookupOrdinaryName, S, nullptr,
11454 llvm::make_unique<DeclFilterCCC<FunctionDecl>>(), CTK_NonError)))
11455 diagnoseTypo(Corrected, PDiag(diag::note_function_suggestion),
11456 /*ErrorRecovery*/false);
11459 // Set a Declarator for the implicit definition: int foo();
11461 AttributeFactory attrFactory;
11462 DeclSpec DS(attrFactory);
11464 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID,
11465 Context.getPrintingPolicy());
11466 (void)Error; // Silence warning.
11467 assert(!Error && "Error setting up implicit decl!");
11468 SourceLocation NoLoc;
11469 Declarator D(DS, Declarator::BlockContext);
11470 D.AddTypeInfo(DeclaratorChunk::getFunction(/*HasProto=*/false,
11471 /*IsAmbiguous=*/false,
11472 /*LParenLoc=*/NoLoc,
11473 /*Params=*/nullptr,
11475 /*EllipsisLoc=*/NoLoc,
11476 /*RParenLoc=*/NoLoc,
11478 /*RefQualifierIsLvalueRef=*/true,
11479 /*RefQualifierLoc=*/NoLoc,
11480 /*ConstQualifierLoc=*/NoLoc,
11481 /*VolatileQualifierLoc=*/NoLoc,
11482 /*RestrictQualifierLoc=*/NoLoc,
11483 /*MutableLoc=*/NoLoc,
11485 /*ESpecRange=*/SourceRange(),
11486 /*Exceptions=*/nullptr,
11487 /*ExceptionRanges=*/nullptr,
11488 /*NumExceptions=*/0,
11489 /*NoexceptExpr=*/nullptr,
11490 /*ExceptionSpecTokens=*/nullptr,
11492 DS.getAttributes(),
11494 D.SetIdentifier(&II, Loc);
11496 // Insert this function into translation-unit scope.
11498 DeclContext *PrevDC = CurContext;
11499 CurContext = Context.getTranslationUnitDecl();
11501 FunctionDecl *FD = cast<FunctionDecl>(ActOnDeclarator(TUScope, D));
11504 CurContext = PrevDC;
11506 AddKnownFunctionAttributes(FD);
11511 /// \brief Adds any function attributes that we know a priori based on
11512 /// the declaration of this function.
11514 /// These attributes can apply both to implicitly-declared builtins
11515 /// (like __builtin___printf_chk) or to library-declared functions
11516 /// like NSLog or printf.
11518 /// We need to check for duplicate attributes both here and where user-written
11519 /// attributes are applied to declarations.
11520 void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) {
11521 if (FD->isInvalidDecl())
11524 // If this is a built-in function, map its builtin attributes to
11525 // actual attributes.
11526 if (unsigned BuiltinID = FD->getBuiltinID()) {
11527 // Handle printf-formatting attributes.
11528 unsigned FormatIdx;
11530 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) {
11531 if (!FD->hasAttr<FormatAttr>()) {
11532 const char *fmt = "printf";
11533 unsigned int NumParams = FD->getNumParams();
11534 if (FormatIdx < NumParams && // NumParams may be 0 (e.g. vfprintf)
11535 FD->getParamDecl(FormatIdx)->getType()->isObjCObjectPointerType())
11537 FD->addAttr(FormatAttr::CreateImplicit(Context,
11538 &Context.Idents.get(fmt),
11540 HasVAListArg ? 0 : FormatIdx+2,
11541 FD->getLocation()));
11544 if (Context.BuiltinInfo.isScanfLike(BuiltinID, FormatIdx,
11546 if (!FD->hasAttr<FormatAttr>())
11547 FD->addAttr(FormatAttr::CreateImplicit(Context,
11548 &Context.Idents.get("scanf"),
11550 HasVAListArg ? 0 : FormatIdx+2,
11551 FD->getLocation()));
11554 // Mark const if we don't care about errno and that is the only
11555 // thing preventing the function from being const. This allows
11556 // IRgen to use LLVM intrinsics for such functions.
11557 if (!getLangOpts().MathErrno &&
11558 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) {
11559 if (!FD->hasAttr<ConstAttr>())
11560 FD->addAttr(ConstAttr::CreateImplicit(Context, FD->getLocation()));
11563 if (Context.BuiltinInfo.isReturnsTwice(BuiltinID) &&
11564 !FD->hasAttr<ReturnsTwiceAttr>())
11565 FD->addAttr(ReturnsTwiceAttr::CreateImplicit(Context,
11566 FD->getLocation()));
11567 if (Context.BuiltinInfo.isNoThrow(BuiltinID) && !FD->hasAttr<NoThrowAttr>())
11568 FD->addAttr(NoThrowAttr::CreateImplicit(Context, FD->getLocation()));
11569 if (Context.BuiltinInfo.isConst(BuiltinID) && !FD->hasAttr<ConstAttr>())
11570 FD->addAttr(ConstAttr::CreateImplicit(Context, FD->getLocation()));
11571 if (getLangOpts().CUDA && getLangOpts().CUDATargetOverloads &&
11572 Context.BuiltinInfo.isTSBuiltin(BuiltinID) &&
11573 !FD->hasAttr<CUDADeviceAttr>() && !FD->hasAttr<CUDAHostAttr>()) {
11574 // Assign appropriate attribute depending on CUDA compilation
11575 // mode and the target builtin belongs to. E.g. during host
11576 // compilation, aux builtins are __device__, the rest are __host__.
11577 if (getLangOpts().CUDAIsDevice !=
11578 Context.BuiltinInfo.isAuxBuiltinID(BuiltinID))
11579 FD->addAttr(CUDADeviceAttr::CreateImplicit(Context, FD->getLocation()));
11581 FD->addAttr(CUDAHostAttr::CreateImplicit(Context, FD->getLocation()));
11585 IdentifierInfo *Name = FD->getIdentifier();
11588 if ((!getLangOpts().CPlusPlus &&
11589 FD->getDeclContext()->isTranslationUnit()) ||
11590 (isa<LinkageSpecDecl>(FD->getDeclContext()) &&
11591 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() ==
11592 LinkageSpecDecl::lang_c)) {
11593 // Okay: this could be a libc/libm/Objective-C function we know
11598 if (Name->isStr("asprintf") || Name->isStr("vasprintf")) {
11599 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be
11600 // target-specific builtins, perhaps?
11601 if (!FD->hasAttr<FormatAttr>())
11602 FD->addAttr(FormatAttr::CreateImplicit(Context,
11603 &Context.Idents.get("printf"), 2,
11604 Name->isStr("vasprintf") ? 0 : 3,
11605 FD->getLocation()));
11608 if (Name->isStr("__CFStringMakeConstantString")) {
11609 // We already have a __builtin___CFStringMakeConstantString,
11610 // but builds that use -fno-constant-cfstrings don't go through that.
11611 if (!FD->hasAttr<FormatArgAttr>())
11612 FD->addAttr(FormatArgAttr::CreateImplicit(Context, 1,
11613 FD->getLocation()));
11617 TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T,
11618 TypeSourceInfo *TInfo) {
11619 assert(D.getIdentifier() && "Wrong callback for declspec without declarator");
11620 assert(!T.isNull() && "GetTypeForDeclarator() returned null type");
11623 assert(D.isInvalidType() && "no declarator info for valid type");
11624 TInfo = Context.getTrivialTypeSourceInfo(T);
11627 // Scope manipulation handled by caller.
11628 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext,
11630 D.getIdentifierLoc(),
11634 // Bail out immediately if we have an invalid declaration.
11635 if (D.isInvalidType()) {
11636 NewTD->setInvalidDecl();
11640 if (D.getDeclSpec().isModulePrivateSpecified()) {
11641 if (CurContext->isFunctionOrMethod())
11642 Diag(NewTD->getLocation(), diag::err_module_private_local)
11643 << 2 << NewTD->getDeclName()
11644 << SourceRange(D.getDeclSpec().getModulePrivateSpecLoc())
11645 << FixItHint::CreateRemoval(D.getDeclSpec().getModulePrivateSpecLoc());
11647 NewTD->setModulePrivate();
11650 // C++ [dcl.typedef]p8:
11651 // If the typedef declaration defines an unnamed class (or
11652 // enum), the first typedef-name declared by the declaration
11653 // to be that class type (or enum type) is used to denote the
11654 // class type (or enum type) for linkage purposes only.
11655 // We need to check whether the type was declared in the declaration.
11656 switch (D.getDeclSpec().getTypeSpecType()) {
11659 case TST_interface:
11662 TagDecl *tagFromDeclSpec = cast<TagDecl>(D.getDeclSpec().getRepAsDecl());
11663 setTagNameForLinkagePurposes(tagFromDeclSpec, NewTD);
11674 /// \brief Check that this is a valid underlying type for an enum declaration.
11675 bool Sema::CheckEnumUnderlyingType(TypeSourceInfo *TI) {
11676 SourceLocation UnderlyingLoc = TI->getTypeLoc().getBeginLoc();
11677 QualType T = TI->getType();
11679 if (T->isDependentType())
11682 if (const BuiltinType *BT = T->getAs<BuiltinType>())
11683 if (BT->isInteger())
11686 Diag(UnderlyingLoc, diag::err_enum_invalid_underlying) << T;
11690 /// Check whether this is a valid redeclaration of a previous enumeration.
11691 /// \return true if the redeclaration was invalid.
11692 bool Sema::CheckEnumRedeclaration(
11693 SourceLocation EnumLoc, bool IsScoped, QualType EnumUnderlyingTy,
11694 bool EnumUnderlyingIsImplicit, const EnumDecl *Prev) {
11695 bool IsFixed = !EnumUnderlyingTy.isNull();
11697 if (IsScoped != Prev->isScoped()) {
11698 Diag(EnumLoc, diag::err_enum_redeclare_scoped_mismatch)
11699 << Prev->isScoped();
11700 Diag(Prev->getLocation(), diag::note_previous_declaration);
11704 if (IsFixed && Prev->isFixed()) {
11705 if (!EnumUnderlyingTy->isDependentType() &&
11706 !Prev->getIntegerType()->isDependentType() &&
11707 !Context.hasSameUnqualifiedType(EnumUnderlyingTy,
11708 Prev->getIntegerType())) {
11709 // TODO: Highlight the underlying type of the redeclaration.
11710 Diag(EnumLoc, diag::err_enum_redeclare_type_mismatch)
11711 << EnumUnderlyingTy << Prev->getIntegerType();
11712 Diag(Prev->getLocation(), diag::note_previous_declaration)
11713 << Prev->getIntegerTypeRange();
11716 } else if (IsFixed && !Prev->isFixed() && EnumUnderlyingIsImplicit) {
11718 } else if (!IsFixed && Prev->isFixed() && !Prev->getIntegerTypeSourceInfo()) {
11720 } else if (IsFixed != Prev->isFixed()) {
11721 Diag(EnumLoc, diag::err_enum_redeclare_fixed_mismatch)
11722 << Prev->isFixed();
11723 Diag(Prev->getLocation(), diag::note_previous_declaration);
11730 /// \brief Get diagnostic %select index for tag kind for
11731 /// redeclaration diagnostic message.
11732 /// WARNING: Indexes apply to particular diagnostics only!
11734 /// \returns diagnostic %select index.
11735 static unsigned getRedeclDiagFromTagKind(TagTypeKind Tag) {
11737 case TTK_Struct: return 0;
11738 case TTK_Interface: return 1;
11739 case TTK_Class: return 2;
11740 default: llvm_unreachable("Invalid tag kind for redecl diagnostic!");
11744 /// \brief Determine if tag kind is a class-key compatible with
11745 /// class for redeclaration (class, struct, or __interface).
11747 /// \returns true iff the tag kind is compatible.
11748 static bool isClassCompatTagKind(TagTypeKind Tag)
11750 return Tag == TTK_Struct || Tag == TTK_Class || Tag == TTK_Interface;
11753 /// \brief Determine whether a tag with a given kind is acceptable
11754 /// as a redeclaration of the given tag declaration.
11756 /// \returns true if the new tag kind is acceptable, false otherwise.
11757 bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous,
11758 TagTypeKind NewTag, bool isDefinition,
11759 SourceLocation NewTagLoc,
11760 const IdentifierInfo *Name) {
11761 // C++ [dcl.type.elab]p3:
11762 // The class-key or enum keyword present in the
11763 // elaborated-type-specifier shall agree in kind with the
11764 // declaration to which the name in the elaborated-type-specifier
11765 // refers. This rule also applies to the form of
11766 // elaborated-type-specifier that declares a class-name or
11767 // friend class since it can be construed as referring to the
11768 // definition of the class. Thus, in any
11769 // elaborated-type-specifier, the enum keyword shall be used to
11770 // refer to an enumeration (7.2), the union class-key shall be
11771 // used to refer to a union (clause 9), and either the class or
11772 // struct class-key shall be used to refer to a class (clause 9)
11773 // declared using the class or struct class-key.
11774 TagTypeKind OldTag = Previous->getTagKind();
11775 if (!isDefinition || !isClassCompatTagKind(NewTag))
11776 if (OldTag == NewTag)
11779 if (isClassCompatTagKind(OldTag) && isClassCompatTagKind(NewTag)) {
11780 // Warn about the struct/class tag mismatch.
11781 bool isTemplate = false;
11782 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous))
11783 isTemplate = Record->getDescribedClassTemplate();
11785 if (!ActiveTemplateInstantiations.empty()) {
11786 // In a template instantiation, do not offer fix-its for tag mismatches
11787 // since they usually mess up the template instead of fixing the problem.
11788 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch)
11789 << getRedeclDiagFromTagKind(NewTag) << isTemplate << Name
11790 << getRedeclDiagFromTagKind(OldTag);
11794 if (isDefinition) {
11795 // On definitions, check previous tags and issue a fix-it for each
11796 // one that doesn't match the current tag.
11797 if (Previous->getDefinition()) {
11798 // Don't suggest fix-its for redefinitions.
11802 bool previousMismatch = false;
11803 for (auto I : Previous->redecls()) {
11804 if (I->getTagKind() != NewTag) {
11805 if (!previousMismatch) {
11806 previousMismatch = true;
11807 Diag(NewTagLoc, diag::warn_struct_class_previous_tag_mismatch)
11808 << getRedeclDiagFromTagKind(NewTag) << isTemplate << Name
11809 << getRedeclDiagFromTagKind(I->getTagKind());
11811 Diag(I->getInnerLocStart(), diag::note_struct_class_suggestion)
11812 << getRedeclDiagFromTagKind(NewTag)
11813 << FixItHint::CreateReplacement(I->getInnerLocStart(),
11814 TypeWithKeyword::getTagTypeKindName(NewTag));
11820 // Check for a previous definition. If current tag and definition
11821 // are same type, do nothing. If no definition, but disagree with
11822 // with previous tag type, give a warning, but no fix-it.
11823 const TagDecl *Redecl = Previous->getDefinition() ?
11824 Previous->getDefinition() : Previous;
11825 if (Redecl->getTagKind() == NewTag) {
11829 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch)
11830 << getRedeclDiagFromTagKind(NewTag) << isTemplate << Name
11831 << getRedeclDiagFromTagKind(OldTag);
11832 Diag(Redecl->getLocation(), diag::note_previous_use);
11834 // If there is a previous definition, suggest a fix-it.
11835 if (Previous->getDefinition()) {
11836 Diag(NewTagLoc, diag::note_struct_class_suggestion)
11837 << getRedeclDiagFromTagKind(Redecl->getTagKind())
11838 << FixItHint::CreateReplacement(SourceRange(NewTagLoc),
11839 TypeWithKeyword::getTagTypeKindName(Redecl->getTagKind()));
11847 /// Add a minimal nested name specifier fixit hint to allow lookup of a tag name
11848 /// from an outer enclosing namespace or file scope inside a friend declaration.
11849 /// This should provide the commented out code in the following snippet:
11853 /// struct Y { friend struct /*N::*/ X; };
11856 static FixItHint createFriendTagNNSFixIt(Sema &SemaRef, NamedDecl *ND, Scope *S,
11857 SourceLocation NameLoc) {
11858 // While the decl is in a namespace, do repeated lookup of that name and see
11859 // if we get the same namespace back. If we do not, continue until
11860 // translation unit scope, at which point we have a fully qualified NNS.
11861 SmallVector<IdentifierInfo *, 4> Namespaces;
11862 DeclContext *DC = ND->getDeclContext()->getRedeclContext();
11863 for (; !DC->isTranslationUnit(); DC = DC->getParent()) {
11864 // This tag should be declared in a namespace, which can only be enclosed by
11865 // other namespaces. Bail if there's an anonymous namespace in the chain.
11866 NamespaceDecl *Namespace = dyn_cast<NamespaceDecl>(DC);
11867 if (!Namespace || Namespace->isAnonymousNamespace())
11868 return FixItHint();
11869 IdentifierInfo *II = Namespace->getIdentifier();
11870 Namespaces.push_back(II);
11871 NamedDecl *Lookup = SemaRef.LookupSingleName(
11872 S, II, NameLoc, Sema::LookupNestedNameSpecifierName);
11873 if (Lookup == Namespace)
11877 // Once we have all the namespaces, reverse them to go outermost first, and
11879 SmallString<64> Insertion;
11880 llvm::raw_svector_ostream OS(Insertion);
11881 if (DC->isTranslationUnit())
11883 std::reverse(Namespaces.begin(), Namespaces.end());
11884 for (auto *II : Namespaces)
11885 OS << II->getName() << "::";
11886 return FixItHint::CreateInsertion(NameLoc, Insertion);
11889 /// \brief Determine whether a tag originally declared in context \p OldDC can
11890 /// be redeclared with an unqualfied name in \p NewDC (assuming name lookup
11891 /// found a declaration in \p OldDC as a previous decl, perhaps through a
11892 /// using-declaration).
11893 static bool isAcceptableTagRedeclContext(Sema &S, DeclContext *OldDC,
11894 DeclContext *NewDC) {
11895 OldDC = OldDC->getRedeclContext();
11896 NewDC = NewDC->getRedeclContext();
11898 if (OldDC->Equals(NewDC))
11901 // In MSVC mode, we allow a redeclaration if the contexts are related (either
11902 // encloses the other).
11903 if (S.getLangOpts().MSVCCompat &&
11904 (OldDC->Encloses(NewDC) || NewDC->Encloses(OldDC)))
11910 /// Find the DeclContext in which a tag is implicitly declared if we see an
11911 /// elaborated type specifier in the specified context, and lookup finds
11913 static DeclContext *getTagInjectionContext(DeclContext *DC) {
11914 while (!DC->isFileContext() && !DC->isFunctionOrMethod())
11915 DC = DC->getParent();
11919 /// Find the Scope in which a tag is implicitly declared if we see an
11920 /// elaborated type specifier in the specified context, and lookup finds
11922 static Scope *getTagInjectionScope(Scope *S, const LangOptions &LangOpts) {
11923 while (S->isClassScope() ||
11924 (LangOpts.CPlusPlus &&
11925 S->isFunctionPrototypeScope()) ||
11926 ((S->getFlags() & Scope::DeclScope) == 0) ||
11927 (S->getEntity() && S->getEntity()->isTransparentContext()))
11928 S = S->getParent();
11932 /// \brief This is invoked when we see 'struct foo' or 'struct {'. In the
11933 /// former case, Name will be non-null. In the later case, Name will be null.
11934 /// TagSpec indicates what kind of tag this is. TUK indicates whether this is a
11935 /// reference/declaration/definition of a tag.
11937 /// \param IsTypeSpecifier \c true if this is a type-specifier (or
11938 /// trailing-type-specifier) other than one in an alias-declaration.
11940 /// \param SkipBody If non-null, will be set to indicate if the caller should
11941 /// skip the definition of this tag and treat it as if it were a declaration.
11942 Decl *Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK,
11943 SourceLocation KWLoc, CXXScopeSpec &SS,
11944 IdentifierInfo *Name, SourceLocation NameLoc,
11945 AttributeList *Attr, AccessSpecifier AS,
11946 SourceLocation ModulePrivateLoc,
11947 MultiTemplateParamsArg TemplateParameterLists,
11948 bool &OwnedDecl, bool &IsDependent,
11949 SourceLocation ScopedEnumKWLoc,
11950 bool ScopedEnumUsesClassTag,
11951 TypeResult UnderlyingType,
11952 bool IsTypeSpecifier, SkipBodyInfo *SkipBody) {
11953 // If this is not a definition, it must have a name.
11954 IdentifierInfo *OrigName = Name;
11955 assert((Name != nullptr || TUK == TUK_Definition) &&
11956 "Nameless record must be a definition!");
11957 assert(TemplateParameterLists.size() == 0 || TUK != TUK_Reference);
11960 TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec);
11961 bool ScopedEnum = ScopedEnumKWLoc.isValid();
11963 // FIXME: Check explicit specializations more carefully.
11964 bool isExplicitSpecialization = false;
11965 bool Invalid = false;
11967 // We only need to do this matching if we have template parameters
11968 // or a scope specifier, which also conveniently avoids this work
11969 // for non-C++ cases.
11970 if (TemplateParameterLists.size() > 0 ||
11971 (SS.isNotEmpty() && TUK != TUK_Reference)) {
11972 if (TemplateParameterList *TemplateParams =
11973 MatchTemplateParametersToScopeSpecifier(
11974 KWLoc, NameLoc, SS, nullptr, TemplateParameterLists,
11975 TUK == TUK_Friend, isExplicitSpecialization, Invalid)) {
11976 if (Kind == TTK_Enum) {
11977 Diag(KWLoc, diag::err_enum_template);
11981 if (TemplateParams->size() > 0) {
11982 // This is a declaration or definition of a class template (which may
11983 // be a member of another template).
11989 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc,
11990 SS, Name, NameLoc, Attr,
11991 TemplateParams, AS,
11993 /*FriendLoc*/SourceLocation(),
11994 TemplateParameterLists.size()-1,
11995 TemplateParameterLists.data(),
11997 return Result.get();
11999 // The "template<>" header is extraneous.
12000 Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams)
12001 << TypeWithKeyword::getTagTypeKindName(Kind) << Name;
12002 isExplicitSpecialization = true;
12007 // Figure out the underlying type if this a enum declaration. We need to do
12008 // this early, because it's needed to detect if this is an incompatible
12010 llvm::PointerUnion<const Type*, TypeSourceInfo*> EnumUnderlying;
12011 bool EnumUnderlyingIsImplicit = false;
12013 if (Kind == TTK_Enum) {
12014 if (UnderlyingType.isInvalid() || (!UnderlyingType.get() && ScopedEnum))
12015 // No underlying type explicitly specified, or we failed to parse the
12016 // type, default to int.
12017 EnumUnderlying = Context.IntTy.getTypePtr();
12018 else if (UnderlyingType.get()) {
12019 // C++0x 7.2p2: The type-specifier-seq of an enum-base shall name an
12020 // integral type; any cv-qualification is ignored.
12021 TypeSourceInfo *TI = nullptr;
12022 GetTypeFromParser(UnderlyingType.get(), &TI);
12023 EnumUnderlying = TI;
12025 if (CheckEnumUnderlyingType(TI))
12026 // Recover by falling back to int.
12027 EnumUnderlying = Context.IntTy.getTypePtr();
12029 if (DiagnoseUnexpandedParameterPack(TI->getTypeLoc().getBeginLoc(), TI,
12030 UPPC_FixedUnderlyingType))
12031 EnumUnderlying = Context.IntTy.getTypePtr();
12033 } else if (Context.getTargetInfo().getCXXABI().isMicrosoft()) {
12034 if (getLangOpts().MSVCCompat || TUK == TUK_Definition) {
12035 // Microsoft enums are always of int type.
12036 EnumUnderlying = Context.IntTy.getTypePtr();
12037 EnumUnderlyingIsImplicit = true;
12042 DeclContext *SearchDC = CurContext;
12043 DeclContext *DC = CurContext;
12044 bool isStdBadAlloc = false;
12046 RedeclarationKind Redecl = ForRedeclaration;
12047 if (TUK == TUK_Friend || TUK == TUK_Reference)
12048 Redecl = NotForRedeclaration;
12050 LookupResult Previous(*this, Name, NameLoc, LookupTagName, Redecl);
12051 if (Name && SS.isNotEmpty()) {
12052 // We have a nested-name tag ('struct foo::bar').
12054 // Check for invalid 'foo::'.
12055 if (SS.isInvalid()) {
12057 goto CreateNewDecl;
12060 // If this is a friend or a reference to a class in a dependent
12061 // context, don't try to make a decl for it.
12062 if (TUK == TUK_Friend || TUK == TUK_Reference) {
12063 DC = computeDeclContext(SS, false);
12065 IsDependent = true;
12069 DC = computeDeclContext(SS, true);
12071 Diag(SS.getRange().getBegin(), diag::err_dependent_nested_name_spec)
12077 if (RequireCompleteDeclContext(SS, DC))
12081 // Look-up name inside 'foo::'.
12082 LookupQualifiedName(Previous, DC);
12084 if (Previous.isAmbiguous())
12087 if (Previous.empty()) {
12088 // Name lookup did not find anything. However, if the
12089 // nested-name-specifier refers to the current instantiation,
12090 // and that current instantiation has any dependent base
12091 // classes, we might find something at instantiation time: treat
12092 // this as a dependent elaborated-type-specifier.
12093 // But this only makes any sense for reference-like lookups.
12094 if (Previous.wasNotFoundInCurrentInstantiation() &&
12095 (TUK == TUK_Reference || TUK == TUK_Friend)) {
12096 IsDependent = true;
12100 // A tag 'foo::bar' must already exist.
12101 Diag(NameLoc, diag::err_not_tag_in_scope)
12102 << Kind << Name << DC << SS.getRange();
12105 goto CreateNewDecl;
12108 // C++14 [class.mem]p14:
12109 // If T is the name of a class, then each of the following shall have a
12110 // name different from T:
12111 // -- every member of class T that is itself a type
12112 if (TUK != TUK_Reference && TUK != TUK_Friend &&
12113 DiagnoseClassNameShadow(SearchDC, DeclarationNameInfo(Name, NameLoc)))
12116 // If this is a named struct, check to see if there was a previous forward
12117 // declaration or definition.
12118 // FIXME: We're looking into outer scopes here, even when we
12119 // shouldn't be. Doing so can result in ambiguities that we
12120 // shouldn't be diagnosing.
12121 LookupName(Previous, S);
12123 // When declaring or defining a tag, ignore ambiguities introduced
12124 // by types using'ed into this scope.
12125 if (Previous.isAmbiguous() &&
12126 (TUK == TUK_Definition || TUK == TUK_Declaration)) {
12127 LookupResult::Filter F = Previous.makeFilter();
12128 while (F.hasNext()) {
12129 NamedDecl *ND = F.next();
12130 if (ND->getDeclContext()->getRedeclContext() != SearchDC)
12136 // C++11 [namespace.memdef]p3:
12137 // If the name in a friend declaration is neither qualified nor
12138 // a template-id and the declaration is a function or an
12139 // elaborated-type-specifier, the lookup to determine whether
12140 // the entity has been previously declared shall not consider
12141 // any scopes outside the innermost enclosing namespace.
12143 // MSVC doesn't implement the above rule for types, so a friend tag
12144 // declaration may be a redeclaration of a type declared in an enclosing
12145 // scope. They do implement this rule for friend functions.
12147 // Does it matter that this should be by scope instead of by
12148 // semantic context?
12149 if (!Previous.empty() && TUK == TUK_Friend) {
12150 DeclContext *EnclosingNS = SearchDC->getEnclosingNamespaceContext();
12151 LookupResult::Filter F = Previous.makeFilter();
12152 bool FriendSawTagOutsideEnclosingNamespace = false;
12153 while (F.hasNext()) {
12154 NamedDecl *ND = F.next();
12155 DeclContext *DC = ND->getDeclContext()->getRedeclContext();
12156 if (DC->isFileContext() &&
12157 !EnclosingNS->Encloses(ND->getDeclContext())) {
12158 if (getLangOpts().MSVCCompat)
12159 FriendSawTagOutsideEnclosingNamespace = true;
12166 // Diagnose this MSVC extension in the easy case where lookup would have
12167 // unambiguously found something outside the enclosing namespace.
12168 if (Previous.isSingleResult() && FriendSawTagOutsideEnclosingNamespace) {
12169 NamedDecl *ND = Previous.getFoundDecl();
12170 Diag(NameLoc, diag::ext_friend_tag_redecl_outside_namespace)
12171 << createFriendTagNNSFixIt(*this, ND, S, NameLoc);
12175 // Note: there used to be some attempt at recovery here.
12176 if (Previous.isAmbiguous())
12179 if (!getLangOpts().CPlusPlus && TUK != TUK_Reference) {
12180 // FIXME: This makes sure that we ignore the contexts associated
12181 // with C structs, unions, and enums when looking for a matching
12182 // tag declaration or definition. See the similar lookup tweak
12183 // in Sema::LookupName; is there a better way to deal with this?
12184 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC))
12185 SearchDC = SearchDC->getParent();
12189 if (Previous.isSingleResult() &&
12190 Previous.getFoundDecl()->isTemplateParameter()) {
12191 // Maybe we will complain about the shadowed template parameter.
12192 DiagnoseTemplateParameterShadow(NameLoc, Previous.getFoundDecl());
12193 // Just pretend that we didn't see the previous declaration.
12197 if (getLangOpts().CPlusPlus && Name && DC && StdNamespace &&
12198 DC->Equals(getStdNamespace()) && Name->isStr("bad_alloc")) {
12199 // This is a declaration of or a reference to "std::bad_alloc".
12200 isStdBadAlloc = true;
12202 if (Previous.empty() && StdBadAlloc) {
12203 // std::bad_alloc has been implicitly declared (but made invisible to
12204 // name lookup). Fill in this implicit declaration as the previous
12205 // declaration, so that the declarations get chained appropriately.
12206 Previous.addDecl(getStdBadAlloc());
12210 // If we didn't find a previous declaration, and this is a reference
12211 // (or friend reference), move to the correct scope. In C++, we
12212 // also need to do a redeclaration lookup there, just in case
12213 // there's a shadow friend decl.
12214 if (Name && Previous.empty() &&
12215 (TUK == TUK_Reference || TUK == TUK_Friend)) {
12216 if (Invalid) goto CreateNewDecl;
12217 assert(SS.isEmpty());
12219 if (TUK == TUK_Reference) {
12220 // C++ [basic.scope.pdecl]p5:
12221 // -- for an elaborated-type-specifier of the form
12223 // class-key identifier
12225 // if the elaborated-type-specifier is used in the
12226 // decl-specifier-seq or parameter-declaration-clause of a
12227 // function defined in namespace scope, the identifier is
12228 // declared as a class-name in the namespace that contains
12229 // the declaration; otherwise, except as a friend
12230 // declaration, the identifier is declared in the smallest
12231 // non-class, non-function-prototype scope that contains the
12234 // C99 6.7.2.3p8 has a similar (but not identical!) provision for
12235 // C structs and unions.
12237 // It is an error in C++ to declare (rather than define) an enum
12238 // type, including via an elaborated type specifier. We'll
12239 // diagnose that later; for now, declare the enum in the same
12240 // scope as we would have picked for any other tag type.
12242 // GNU C also supports this behavior as part of its incomplete
12243 // enum types extension, while GNU C++ does not.
12245 // Find the context where we'll be declaring the tag.
12246 // FIXME: We would like to maintain the current DeclContext as the
12247 // lexical context,
12248 SearchDC = getTagInjectionContext(SearchDC);
12250 // Find the scope where we'll be declaring the tag.
12251 S = getTagInjectionScope(S, getLangOpts());
12253 assert(TUK == TUK_Friend);
12254 // C++ [namespace.memdef]p3:
12255 // If a friend declaration in a non-local class first declares a
12256 // class or function, the friend class or function is a member of
12257 // the innermost enclosing namespace.
12258 SearchDC = SearchDC->getEnclosingNamespaceContext();
12261 // In C++, we need to do a redeclaration lookup to properly
12262 // diagnose some problems.
12263 // FIXME: redeclaration lookup is also used (with and without C++) to find a
12264 // hidden declaration so that we don't get ambiguity errors when using a
12265 // type declared by an elaborated-type-specifier. In C that is not correct
12266 // and we should instead merge compatible types found by lookup.
12267 if (getLangOpts().CPlusPlus) {
12268 Previous.setRedeclarationKind(ForRedeclaration);
12269 LookupQualifiedName(Previous, SearchDC);
12271 Previous.setRedeclarationKind(ForRedeclaration);
12272 LookupName(Previous, S);
12276 // If we have a known previous declaration to use, then use it.
12277 if (Previous.empty() && SkipBody && SkipBody->Previous)
12278 Previous.addDecl(SkipBody->Previous);
12280 if (!Previous.empty()) {
12281 NamedDecl *PrevDecl = Previous.getFoundDecl();
12282 NamedDecl *DirectPrevDecl = Previous.getRepresentativeDecl();
12284 // It's okay to have a tag decl in the same scope as a typedef
12285 // which hides a tag decl in the same scope. Finding this
12286 // insanity with a redeclaration lookup can only actually happen
12289 // This is also okay for elaborated-type-specifiers, which is
12290 // technically forbidden by the current standard but which is
12291 // okay according to the likely resolution of an open issue;
12292 // see http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#407
12293 if (getLangOpts().CPlusPlus) {
12294 if (TypedefNameDecl *TD = dyn_cast<TypedefNameDecl>(PrevDecl)) {
12295 if (const TagType *TT = TD->getUnderlyingType()->getAs<TagType>()) {
12296 TagDecl *Tag = TT->getDecl();
12297 if (Tag->getDeclName() == Name &&
12298 Tag->getDeclContext()->getRedeclContext()
12299 ->Equals(TD->getDeclContext()->getRedeclContext())) {
12302 Previous.addDecl(Tag);
12303 Previous.resolveKind();
12309 // If this is a redeclaration of a using shadow declaration, it must
12310 // declare a tag in the same context. In MSVC mode, we allow a
12311 // redefinition if either context is within the other.
12312 if (auto *Shadow = dyn_cast<UsingShadowDecl>(DirectPrevDecl)) {
12313 auto *OldTag = dyn_cast<TagDecl>(PrevDecl);
12314 if (SS.isEmpty() && TUK != TUK_Reference && TUK != TUK_Friend &&
12315 isDeclInScope(Shadow, SearchDC, S, isExplicitSpecialization) &&
12316 !(OldTag && isAcceptableTagRedeclContext(
12317 *this, OldTag->getDeclContext(), SearchDC))) {
12318 Diag(KWLoc, diag::err_using_decl_conflict_reverse);
12319 Diag(Shadow->getTargetDecl()->getLocation(),
12320 diag::note_using_decl_target);
12321 Diag(Shadow->getUsingDecl()->getLocation(), diag::note_using_decl)
12323 // Recover by ignoring the old declaration.
12325 goto CreateNewDecl;
12329 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) {
12330 // If this is a use of a previous tag, or if the tag is already declared
12331 // in the same scope (so that the definition/declaration completes or
12332 // rementions the tag), reuse the decl.
12333 if (TUK == TUK_Reference || TUK == TUK_Friend ||
12334 isDeclInScope(DirectPrevDecl, SearchDC, S,
12335 SS.isNotEmpty() || isExplicitSpecialization)) {
12336 // Make sure that this wasn't declared as an enum and now used as a
12337 // struct or something similar.
12338 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind,
12339 TUK == TUK_Definition, KWLoc,
12341 bool SafeToContinue
12342 = (PrevTagDecl->getTagKind() != TTK_Enum &&
12344 if (SafeToContinue)
12345 Diag(KWLoc, diag::err_use_with_wrong_tag)
12347 << FixItHint::CreateReplacement(SourceRange(KWLoc),
12348 PrevTagDecl->getKindName());
12350 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name;
12351 Diag(PrevTagDecl->getLocation(), diag::note_previous_use);
12353 if (SafeToContinue)
12354 Kind = PrevTagDecl->getTagKind();
12356 // Recover by making this an anonymous redefinition.
12363 if (Kind == TTK_Enum && PrevTagDecl->getTagKind() == TTK_Enum) {
12364 const EnumDecl *PrevEnum = cast<EnumDecl>(PrevTagDecl);
12366 // If this is an elaborated-type-specifier for a scoped enumeration,
12367 // the 'class' keyword is not necessary and not permitted.
12368 if (TUK == TUK_Reference || TUK == TUK_Friend) {
12370 Diag(ScopedEnumKWLoc, diag::err_enum_class_reference)
12371 << PrevEnum->isScoped()
12372 << FixItHint::CreateRemoval(ScopedEnumKWLoc);
12373 return PrevTagDecl;
12376 QualType EnumUnderlyingTy;
12377 if (TypeSourceInfo *TI = EnumUnderlying.dyn_cast<TypeSourceInfo*>())
12378 EnumUnderlyingTy = TI->getType().getUnqualifiedType();
12379 else if (const Type *T = EnumUnderlying.dyn_cast<const Type*>())
12380 EnumUnderlyingTy = QualType(T, 0);
12382 // All conflicts with previous declarations are recovered by
12383 // returning the previous declaration, unless this is a definition,
12384 // in which case we want the caller to bail out.
12385 if (CheckEnumRedeclaration(NameLoc.isValid() ? NameLoc : KWLoc,
12386 ScopedEnum, EnumUnderlyingTy,
12387 EnumUnderlyingIsImplicit, PrevEnum))
12388 return TUK == TUK_Declaration ? PrevTagDecl : nullptr;
12391 // C++11 [class.mem]p1:
12392 // A member shall not be declared twice in the member-specification,
12393 // except that a nested class or member class template can be declared
12394 // and then later defined.
12395 if (TUK == TUK_Declaration && PrevDecl->isCXXClassMember() &&
12396 S->isDeclScope(PrevDecl)) {
12397 Diag(NameLoc, diag::ext_member_redeclared);
12398 Diag(PrevTagDecl->getLocation(), diag::note_previous_declaration);
12402 // If this is a use, just return the declaration we found, unless
12403 // we have attributes.
12404 if (TUK == TUK_Reference || TUK == TUK_Friend) {
12406 // FIXME: Diagnose these attributes. For now, we create a new
12407 // declaration to hold them.
12408 } else if (TUK == TUK_Reference &&
12409 (PrevTagDecl->getFriendObjectKind() ==
12410 Decl::FOK_Undeclared ||
12411 PP.getModuleContainingLocation(
12412 PrevDecl->getLocation()) !=
12413 PP.getModuleContainingLocation(KWLoc)) &&
12415 // This declaration is a reference to an existing entity, but
12416 // has different visibility from that entity: it either makes
12417 // a friend visible or it makes a type visible in a new module.
12418 // In either case, create a new declaration. We only do this if
12419 // the declaration would have meant the same thing if no prior
12420 // declaration were found, that is, if it was found in the same
12421 // scope where we would have injected a declaration.
12422 if (!getTagInjectionContext(CurContext)->getRedeclContext()
12423 ->Equals(PrevDecl->getDeclContext()->getRedeclContext()))
12424 return PrevTagDecl;
12425 // This is in the injected scope, create a new declaration in
12427 S = getTagInjectionScope(S, getLangOpts());
12429 return PrevTagDecl;
12433 // Diagnose attempts to redefine a tag.
12434 if (TUK == TUK_Definition) {
12435 if (NamedDecl *Def = PrevTagDecl->getDefinition()) {
12436 // If we're defining a specialization and the previous definition
12437 // is from an implicit instantiation, don't emit an error
12438 // here; we'll catch this in the general case below.
12439 bool IsExplicitSpecializationAfterInstantiation = false;
12440 if (isExplicitSpecialization) {
12441 if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(Def))
12442 IsExplicitSpecializationAfterInstantiation =
12443 RD->getTemplateSpecializationKind() !=
12444 TSK_ExplicitSpecialization;
12445 else if (EnumDecl *ED = dyn_cast<EnumDecl>(Def))
12446 IsExplicitSpecializationAfterInstantiation =
12447 ED->getTemplateSpecializationKind() !=
12448 TSK_ExplicitSpecialization;
12451 NamedDecl *Hidden = nullptr;
12452 if (SkipBody && getLangOpts().CPlusPlus &&
12453 !hasVisibleDefinition(Def, &Hidden)) {
12454 // There is a definition of this tag, but it is not visible. We
12455 // explicitly make use of C++'s one definition rule here, and
12456 // assume that this definition is identical to the hidden one
12457 // we already have. Make the existing definition visible and
12458 // use it in place of this one.
12459 SkipBody->ShouldSkip = true;
12460 makeMergedDefinitionVisible(Hidden, KWLoc);
12462 } else if (!IsExplicitSpecializationAfterInstantiation) {
12463 // A redeclaration in function prototype scope in C isn't
12464 // visible elsewhere, so merely issue a warning.
12465 if (!getLangOpts().CPlusPlus && S->containedInPrototypeScope())
12466 Diag(NameLoc, diag::warn_redefinition_in_param_list) << Name;
12468 Diag(NameLoc, diag::err_redefinition) << Name;
12469 Diag(Def->getLocation(), diag::note_previous_definition);
12470 // If this is a redefinition, recover by making this
12471 // struct be anonymous, which will make any later
12472 // references get the previous definition.
12478 // If the type is currently being defined, complain
12479 // about a nested redefinition.
12480 auto *TD = Context.getTagDeclType(PrevTagDecl)->getAsTagDecl();
12481 if (TD->isBeingDefined()) {
12482 Diag(NameLoc, diag::err_nested_redefinition) << Name;
12483 Diag(PrevTagDecl->getLocation(),
12484 diag::note_previous_definition);
12491 // Okay, this is definition of a previously declared or referenced
12492 // tag. We're going to create a new Decl for it.
12495 // Okay, we're going to make a redeclaration. If this is some kind
12496 // of reference, make sure we build the redeclaration in the same DC
12497 // as the original, and ignore the current access specifier.
12498 if (TUK == TUK_Friend || TUK == TUK_Reference) {
12499 SearchDC = PrevTagDecl->getDeclContext();
12503 // If we get here we have (another) forward declaration or we
12504 // have a definition. Just create a new decl.
12507 // If we get here, this is a definition of a new tag type in a nested
12508 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a
12509 // new decl/type. We set PrevDecl to NULL so that the entities
12510 // have distinct types.
12513 // If we get here, we're going to create a new Decl. If PrevDecl
12514 // is non-NULL, it's a definition of the tag declared by
12515 // PrevDecl. If it's NULL, we have a new definition.
12517 // Otherwise, PrevDecl is not a tag, but was found with tag
12518 // lookup. This is only actually possible in C++, where a few
12519 // things like templates still live in the tag namespace.
12521 // Use a better diagnostic if an elaborated-type-specifier
12522 // found the wrong kind of type on the first
12523 // (non-redeclaration) lookup.
12524 if ((TUK == TUK_Reference || TUK == TUK_Friend) &&
12525 !Previous.isForRedeclaration()) {
12527 if (isa<TypedefDecl>(PrevDecl)) Kind = 1;
12528 else if (isa<TypeAliasDecl>(PrevDecl)) Kind = 2;
12529 else if (isa<ClassTemplateDecl>(PrevDecl)) Kind = 3;
12530 Diag(NameLoc, diag::err_tag_reference_non_tag) << Kind;
12531 Diag(PrevDecl->getLocation(), diag::note_declared_at);
12534 // Otherwise, only diagnose if the declaration is in scope.
12535 } else if (!isDeclInScope(DirectPrevDecl, SearchDC, S,
12536 SS.isNotEmpty() || isExplicitSpecialization)) {
12539 // Diagnose implicit declarations introduced by elaborated types.
12540 } else if (TUK == TUK_Reference || TUK == TUK_Friend) {
12542 if (isa<TypedefDecl>(PrevDecl)) Kind = 1;
12543 else if (isa<TypeAliasDecl>(PrevDecl)) Kind = 2;
12544 else if (isa<ClassTemplateDecl>(PrevDecl)) Kind = 3;
12545 Diag(NameLoc, diag::err_tag_reference_conflict) << Kind;
12546 Diag(PrevDecl->getLocation(), diag::note_previous_decl) << PrevDecl;
12549 // Otherwise it's a declaration. Call out a particularly common
12551 } else if (TypedefNameDecl *TND = dyn_cast<TypedefNameDecl>(PrevDecl)) {
12553 if (isa<TypeAliasDecl>(PrevDecl)) Kind = 1;
12554 Diag(NameLoc, diag::err_tag_definition_of_typedef)
12555 << Name << Kind << TND->getUnderlyingType();
12556 Diag(PrevDecl->getLocation(), diag::note_previous_decl) << PrevDecl;
12559 // Otherwise, diagnose.
12561 // The tag name clashes with something else in the target scope,
12562 // issue an error and recover by making this tag be anonymous.
12563 Diag(NameLoc, diag::err_redefinition_different_kind) << Name;
12564 Diag(PrevDecl->getLocation(), diag::note_previous_definition);
12569 // The existing declaration isn't relevant to us; we're in a
12570 // new scope, so clear out the previous declaration.
12577 TagDecl *PrevDecl = nullptr;
12578 if (Previous.isSingleResult())
12579 PrevDecl = cast<TagDecl>(Previous.getFoundDecl());
12581 // If there is an identifier, use the location of the identifier as the
12582 // location of the decl, otherwise use the location of the struct/union
12584 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc;
12586 // Otherwise, create a new declaration. If there is a previous
12587 // declaration of the same entity, the two will be linked via
12591 bool IsForwardReference = false;
12592 if (Kind == TTK_Enum) {
12593 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.:
12594 // enum X { A, B, C } D; D should chain to X.
12595 New = EnumDecl::Create(Context, SearchDC, KWLoc, Loc, Name,
12596 cast_or_null<EnumDecl>(PrevDecl), ScopedEnum,
12597 ScopedEnumUsesClassTag, !EnumUnderlying.isNull());
12598 // If this is an undefined enum, warn.
12599 if (TUK != TUK_Definition && !Invalid) {
12601 if ((getLangOpts().CPlusPlus11 || getLangOpts().ObjC2) &&
12602 cast<EnumDecl>(New)->isFixed()) {
12603 // C++0x: 7.2p2: opaque-enum-declaration.
12604 // Conflicts are diagnosed above. Do nothing.
12606 else if (PrevDecl && (Def = cast<EnumDecl>(PrevDecl)->getDefinition())) {
12607 Diag(Loc, diag::ext_forward_ref_enum_def)
12609 Diag(Def->getLocation(), diag::note_previous_definition);
12611 unsigned DiagID = diag::ext_forward_ref_enum;
12612 if (getLangOpts().MSVCCompat)
12613 DiagID = diag::ext_ms_forward_ref_enum;
12614 else if (getLangOpts().CPlusPlus)
12615 DiagID = diag::err_forward_ref_enum;
12618 // If this is a forward-declared reference to an enumeration, make a
12619 // note of it; we won't actually be introducing the declaration into
12620 // the declaration context.
12621 if (TUK == TUK_Reference)
12622 IsForwardReference = true;
12626 if (EnumUnderlying) {
12627 EnumDecl *ED = cast<EnumDecl>(New);
12628 if (TypeSourceInfo *TI = EnumUnderlying.dyn_cast<TypeSourceInfo*>())
12629 ED->setIntegerTypeSourceInfo(TI);
12631 ED->setIntegerType(QualType(EnumUnderlying.get<const Type*>(), 0));
12632 ED->setPromotionType(ED->getIntegerType());
12635 // struct/union/class
12637 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.:
12638 // struct X { int A; } D; D should chain to X.
12639 if (getLangOpts().CPlusPlus) {
12640 // FIXME: Look for a way to use RecordDecl for simple structs.
12641 New = CXXRecordDecl::Create(Context, Kind, SearchDC, KWLoc, Loc, Name,
12642 cast_or_null<CXXRecordDecl>(PrevDecl));
12644 if (isStdBadAlloc && (!StdBadAlloc || getStdBadAlloc()->isImplicit()))
12645 StdBadAlloc = cast<CXXRecordDecl>(New);
12647 New = RecordDecl::Create(Context, Kind, SearchDC, KWLoc, Loc, Name,
12648 cast_or_null<RecordDecl>(PrevDecl));
12651 // C++11 [dcl.type]p3:
12652 // A type-specifier-seq shall not define a class or enumeration [...].
12653 if (getLangOpts().CPlusPlus && IsTypeSpecifier && TUK == TUK_Definition) {
12654 Diag(New->getLocation(), diag::err_type_defined_in_type_specifier)
12655 << Context.getTagDeclType(New);
12659 // Maybe add qualifier info.
12660 if (SS.isNotEmpty()) {
12662 // If this is either a declaration or a definition, check the
12663 // nested-name-specifier against the current context. We don't do this
12664 // for explicit specializations, because they have similar checking
12665 // (with more specific diagnostics) in the call to
12666 // CheckMemberSpecialization, below.
12667 if (!isExplicitSpecialization &&
12668 (TUK == TUK_Definition || TUK == TUK_Declaration) &&
12669 diagnoseQualifiedDeclaration(SS, DC, OrigName, Loc))
12672 New->setQualifierInfo(SS.getWithLocInContext(Context));
12673 if (TemplateParameterLists.size() > 0) {
12674 New->setTemplateParameterListsInfo(Context, TemplateParameterLists);
12681 if (RecordDecl *RD = dyn_cast<RecordDecl>(New)) {
12682 // Add alignment attributes if necessary; these attributes are checked when
12683 // the ASTContext lays out the structure.
12685 // It is important for implementing the correct semantics that this
12686 // happen here (in act on tag decl). The #pragma pack stack is
12687 // maintained as a result of parser callbacks which can occur at
12688 // many points during the parsing of a struct declaration (because
12689 // the #pragma tokens are effectively skipped over during the
12690 // parsing of the struct).
12691 if (TUK == TUK_Definition) {
12692 AddAlignmentAttributesForRecord(RD);
12693 AddMsStructLayoutForRecord(RD);
12697 if (ModulePrivateLoc.isValid()) {
12698 if (isExplicitSpecialization)
12699 Diag(New->getLocation(), diag::err_module_private_specialization)
12701 << FixItHint::CreateRemoval(ModulePrivateLoc);
12702 // __module_private__ does not apply to local classes. However, we only
12703 // diagnose this as an error when the declaration specifiers are
12704 // freestanding. Here, we just ignore the __module_private__.
12705 else if (!SearchDC->isFunctionOrMethod())
12706 New->setModulePrivate();
12709 // If this is a specialization of a member class (of a class template),
12710 // check the specialization.
12711 if (isExplicitSpecialization && CheckMemberSpecialization(New, Previous))
12714 // If we're declaring or defining a tag in function prototype scope in C,
12715 // note that this type can only be used within the function and add it to
12716 // the list of decls to inject into the function definition scope.
12717 if ((Name || Kind == TTK_Enum) &&
12718 getNonFieldDeclScope(S)->isFunctionPrototypeScope()) {
12719 if (getLangOpts().CPlusPlus) {
12720 // C++ [dcl.fct]p6:
12721 // Types shall not be defined in return or parameter types.
12722 if (TUK == TUK_Definition && !IsTypeSpecifier) {
12723 Diag(Loc, diag::err_type_defined_in_param_type)
12727 } else if (!PrevDecl) {
12728 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New);
12730 DeclsInPrototypeScope.push_back(New);
12734 New->setInvalidDecl();
12737 ProcessDeclAttributeList(S, New, Attr);
12739 // Set the lexical context. If the tag has a C++ scope specifier, the
12740 // lexical context will be different from the semantic context.
12741 New->setLexicalDeclContext(CurContext);
12743 // Mark this as a friend decl if applicable.
12744 // In Microsoft mode, a friend declaration also acts as a forward
12745 // declaration so we always pass true to setObjectOfFriendDecl to make
12746 // the tag name visible.
12747 if (TUK == TUK_Friend)
12748 New->setObjectOfFriendDecl(getLangOpts().MSVCCompat);
12750 // Set the access specifier.
12751 if (!Invalid && SearchDC->isRecord())
12752 SetMemberAccessSpecifier(New, PrevDecl, AS);
12754 if (TUK == TUK_Definition)
12755 New->startDefinition();
12757 // If this has an identifier, add it to the scope stack.
12758 if (TUK == TUK_Friend) {
12759 // We might be replacing an existing declaration in the lookup tables;
12760 // if so, borrow its access specifier.
12762 New->setAccess(PrevDecl->getAccess());
12764 DeclContext *DC = New->getDeclContext()->getRedeclContext();
12765 DC->makeDeclVisibleInContext(New);
12766 if (Name) // can be null along some error paths
12767 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC))
12768 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false);
12770 S = getNonFieldDeclScope(S);
12771 PushOnScopeChains(New, S, !IsForwardReference);
12772 if (IsForwardReference)
12773 SearchDC->makeDeclVisibleInContext(New);
12775 CurContext->addDecl(New);
12778 // If this is the C FILE type, notify the AST context.
12779 if (IdentifierInfo *II = New->getIdentifier())
12780 if (!New->isInvalidDecl() &&
12781 New->getDeclContext()->getRedeclContext()->isTranslationUnit() &&
12783 Context.setFILEDecl(New);
12786 mergeDeclAttributes(New, PrevDecl);
12788 // If there's a #pragma GCC visibility in scope, set the visibility of this
12790 AddPushedVisibilityAttribute(New);
12793 // In C++, don't return an invalid declaration. We can't recover well from
12794 // the cases where we make the type anonymous.
12795 return (Invalid && getLangOpts().CPlusPlus) ? nullptr : New;
12798 void Sema::ActOnTagStartDefinition(Scope *S, Decl *TagD) {
12799 AdjustDeclIfTemplate(TagD);
12800 TagDecl *Tag = cast<TagDecl>(TagD);
12802 // Enter the tag context.
12803 PushDeclContext(S, Tag);
12805 ActOnDocumentableDecl(TagD);
12807 // If there's a #pragma GCC visibility in scope, set the visibility of this
12809 AddPushedVisibilityAttribute(Tag);
12812 Decl *Sema::ActOnObjCContainerStartDefinition(Decl *IDecl) {
12813 assert(isa<ObjCContainerDecl>(IDecl) &&
12814 "ActOnObjCContainerStartDefinition - Not ObjCContainerDecl");
12815 DeclContext *OCD = cast<DeclContext>(IDecl);
12816 assert(getContainingDC(OCD) == CurContext &&
12817 "The next DeclContext should be lexically contained in the current one.");
12822 void Sema::ActOnStartCXXMemberDeclarations(Scope *S, Decl *TagD,
12823 SourceLocation FinalLoc,
12824 bool IsFinalSpelledSealed,
12825 SourceLocation LBraceLoc) {
12826 AdjustDeclIfTemplate(TagD);
12827 CXXRecordDecl *Record = cast<CXXRecordDecl>(TagD);
12829 FieldCollector->StartClass();
12831 if (!Record->getIdentifier())
12834 if (FinalLoc.isValid())
12835 Record->addAttr(new (Context)
12836 FinalAttr(FinalLoc, Context, IsFinalSpelledSealed));
12839 // [...] The class-name is also inserted into the scope of the
12840 // class itself; this is known as the injected-class-name. For
12841 // purposes of access checking, the injected-class-name is treated
12842 // as if it were a public member name.
12843 CXXRecordDecl *InjectedClassName
12844 = CXXRecordDecl::Create(Context, Record->getTagKind(), CurContext,
12845 Record->getLocStart(), Record->getLocation(),
12846 Record->getIdentifier(),
12847 /*PrevDecl=*/nullptr,
12848 /*DelayTypeCreation=*/true);
12849 Context.getTypeDeclType(InjectedClassName, Record);
12850 InjectedClassName->setImplicit();
12851 InjectedClassName->setAccess(AS_public);
12852 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate())
12853 InjectedClassName->setDescribedClassTemplate(Template);
12854 PushOnScopeChains(InjectedClassName, S);
12855 assert(InjectedClassName->isInjectedClassName() &&
12856 "Broken injected-class-name");
12859 void Sema::ActOnTagFinishDefinition(Scope *S, Decl *TagD,
12860 SourceLocation RBraceLoc) {
12861 AdjustDeclIfTemplate(TagD);
12862 TagDecl *Tag = cast<TagDecl>(TagD);
12863 Tag->setRBraceLoc(RBraceLoc);
12865 // Make sure we "complete" the definition even it is invalid.
12866 if (Tag->isBeingDefined()) {
12867 assert(Tag->isInvalidDecl() && "We should already have completed it");
12868 if (RecordDecl *RD = dyn_cast<RecordDecl>(Tag))
12869 RD->completeDefinition();
12872 if (isa<CXXRecordDecl>(Tag))
12873 FieldCollector->FinishClass();
12875 // Exit this scope of this tag's definition.
12878 if (getCurLexicalContext()->isObjCContainer() &&
12879 Tag->getDeclContext()->isFileContext())
12880 Tag->setTopLevelDeclInObjCContainer();
12882 // Notify the consumer that we've defined a tag.
12883 if (!Tag->isInvalidDecl())
12884 Consumer.HandleTagDeclDefinition(Tag);
12887 void Sema::ActOnObjCContainerFinishDefinition() {
12888 // Exit this scope of this interface definition.
12892 void Sema::ActOnObjCTemporaryExitContainerContext(DeclContext *DC) {
12893 assert(DC == CurContext && "Mismatch of container contexts");
12894 OriginalLexicalContext = DC;
12895 ActOnObjCContainerFinishDefinition();
12898 void Sema::ActOnObjCReenterContainerContext(DeclContext *DC) {
12899 ActOnObjCContainerStartDefinition(cast<Decl>(DC));
12900 OriginalLexicalContext = nullptr;
12903 void Sema::ActOnTagDefinitionError(Scope *S, Decl *TagD) {
12904 AdjustDeclIfTemplate(TagD);
12905 TagDecl *Tag = cast<TagDecl>(TagD);
12906 Tag->setInvalidDecl();
12908 // Make sure we "complete" the definition even it is invalid.
12909 if (Tag->isBeingDefined()) {
12910 if (RecordDecl *RD = dyn_cast<RecordDecl>(Tag))
12911 RD->completeDefinition();
12914 // We're undoing ActOnTagStartDefinition here, not
12915 // ActOnStartCXXMemberDeclarations, so we don't have to mess with
12916 // the FieldCollector.
12921 // Note that FieldName may be null for anonymous bitfields.
12922 ExprResult Sema::VerifyBitField(SourceLocation FieldLoc,
12923 IdentifierInfo *FieldName,
12924 QualType FieldTy, bool IsMsStruct,
12925 Expr *BitWidth, bool *ZeroWidth) {
12926 // Default to true; that shouldn't confuse checks for emptiness
12930 // C99 6.7.2.1p4 - verify the field type.
12931 // C++ 9.6p3: A bit-field shall have integral or enumeration type.
12932 if (!FieldTy->isDependentType() && !FieldTy->isIntegralOrEnumerationType()) {
12933 // Handle incomplete types with specific error.
12934 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete))
12935 return ExprError();
12937 return Diag(FieldLoc, diag::err_not_integral_type_bitfield)
12938 << FieldName << FieldTy << BitWidth->getSourceRange();
12939 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield)
12940 << FieldTy << BitWidth->getSourceRange();
12941 } else if (DiagnoseUnexpandedParameterPack(const_cast<Expr *>(BitWidth),
12942 UPPC_BitFieldWidth))
12943 return ExprError();
12945 // If the bit-width is type- or value-dependent, don't try to check
12947 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent())
12950 llvm::APSInt Value;
12951 ExprResult ICE = VerifyIntegerConstantExpression(BitWidth, &Value);
12952 if (ICE.isInvalid())
12954 BitWidth = ICE.get();
12956 if (Value != 0 && ZeroWidth)
12957 *ZeroWidth = false;
12959 // Zero-width bitfield is ok for anonymous field.
12960 if (Value == 0 && FieldName)
12961 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName;
12963 if (Value.isSigned() && Value.isNegative()) {
12965 return Diag(FieldLoc, diag::err_bitfield_has_negative_width)
12966 << FieldName << Value.toString(10);
12967 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width)
12968 << Value.toString(10);
12971 if (!FieldTy->isDependentType()) {
12972 uint64_t TypeStorageSize = Context.getTypeSize(FieldTy);
12973 uint64_t TypeWidth = Context.getIntWidth(FieldTy);
12974 bool BitfieldIsOverwide = Value.ugt(TypeWidth);
12976 // Over-wide bitfields are an error in C or when using the MSVC bitfield
12978 bool CStdConstraintViolation =
12979 BitfieldIsOverwide && !getLangOpts().CPlusPlus;
12980 bool MSBitfieldViolation =
12981 Value.ugt(TypeStorageSize) &&
12982 (IsMsStruct || Context.getTargetInfo().getCXXABI().isMicrosoft());
12983 if (CStdConstraintViolation || MSBitfieldViolation) {
12984 unsigned DiagWidth =
12985 CStdConstraintViolation ? TypeWidth : TypeStorageSize;
12987 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_width)
12988 << FieldName << (unsigned)Value.getZExtValue()
12989 << !CStdConstraintViolation << DiagWidth;
12991 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_width)
12992 << (unsigned)Value.getZExtValue() << !CStdConstraintViolation
12996 // Warn on types where the user might conceivably expect to get all
12997 // specified bits as value bits: that's all integral types other than
12999 if (BitfieldIsOverwide && !FieldTy->isBooleanType()) {
13001 Diag(FieldLoc, diag::warn_bitfield_width_exceeds_type_width)
13002 << FieldName << (unsigned)Value.getZExtValue()
13003 << (unsigned)TypeWidth;
13005 Diag(FieldLoc, diag::warn_anon_bitfield_width_exceeds_type_width)
13006 << (unsigned)Value.getZExtValue() << (unsigned)TypeWidth;
13013 /// ActOnField - Each field of a C struct/union is passed into this in order
13014 /// to create a FieldDecl object for it.
13015 Decl *Sema::ActOnField(Scope *S, Decl *TagD, SourceLocation DeclStart,
13016 Declarator &D, Expr *BitfieldWidth) {
13017 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD),
13018 DeclStart, D, static_cast<Expr*>(BitfieldWidth),
13019 /*InitStyle=*/ICIS_NoInit, AS_public);
13023 /// HandleField - Analyze a field of a C struct or a C++ data member.
13025 FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record,
13026 SourceLocation DeclStart,
13027 Declarator &D, Expr *BitWidth,
13028 InClassInitStyle InitStyle,
13029 AccessSpecifier AS) {
13030 IdentifierInfo *II = D.getIdentifier();
13031 SourceLocation Loc = DeclStart;
13032 if (II) Loc = D.getIdentifierLoc();
13034 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S);
13035 QualType T = TInfo->getType();
13036 if (getLangOpts().CPlusPlus) {
13037 CheckExtraCXXDefaultArguments(D);
13039 if (DiagnoseUnexpandedParameterPack(D.getIdentifierLoc(), TInfo,
13040 UPPC_DataMemberType)) {
13041 D.setInvalidType();
13043 TInfo = Context.getTrivialTypeSourceInfo(T, Loc);
13047 // TR 18037 does not allow fields to be declared with address spaces.
13048 if (T.getQualifiers().hasAddressSpace()) {
13049 Diag(Loc, diag::err_field_with_address_space);
13050 D.setInvalidType();
13053 // OpenCL 1.2 spec, s6.9 r:
13054 // The event type cannot be used to declare a structure or union field.
13055 if (LangOpts.OpenCL && T->isEventT()) {
13056 Diag(Loc, diag::err_event_t_struct_field);
13057 D.setInvalidType();
13060 DiagnoseFunctionSpecifiers(D.getDeclSpec());
13062 if (DeclSpec::TSCS TSCS = D.getDeclSpec().getThreadStorageClassSpec())
13063 Diag(D.getDeclSpec().getThreadStorageClassSpecLoc(),
13064 diag::err_invalid_thread)
13065 << DeclSpec::getSpecifierName(TSCS);
13067 // Check to see if this name was declared as a member previously
13068 NamedDecl *PrevDecl = nullptr;
13069 LookupResult Previous(*this, II, Loc, LookupMemberName, ForRedeclaration);
13070 LookupName(Previous, S);
13071 switch (Previous.getResultKind()) {
13072 case LookupResult::Found:
13073 case LookupResult::FoundUnresolvedValue:
13074 PrevDecl = Previous.getAsSingle<NamedDecl>();
13077 case LookupResult::FoundOverloaded:
13078 PrevDecl = Previous.getRepresentativeDecl();
13081 case LookupResult::NotFound:
13082 case LookupResult::NotFoundInCurrentInstantiation:
13083 case LookupResult::Ambiguous:
13086 Previous.suppressDiagnostics();
13088 if (PrevDecl && PrevDecl->isTemplateParameter()) {
13089 // Maybe we will complain about the shadowed template parameter.
13090 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl);
13091 // Just pretend that we didn't see the previous declaration.
13092 PrevDecl = nullptr;
13095 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S))
13096 PrevDecl = nullptr;
13099 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable);
13100 SourceLocation TSSL = D.getLocStart();
13102 = CheckFieldDecl(II, T, TInfo, Record, Loc, Mutable, BitWidth, InitStyle,
13103 TSSL, AS, PrevDecl, &D);
13105 if (NewFD->isInvalidDecl())
13106 Record->setInvalidDecl();
13108 if (D.getDeclSpec().isModulePrivateSpecified())
13109 NewFD->setModulePrivate();
13111 if (NewFD->isInvalidDecl() && PrevDecl) {
13112 // Don't introduce NewFD into scope; there's already something
13113 // with the same name in the same scope.
13115 PushOnScopeChains(NewFD, S);
13117 Record->addDecl(NewFD);
13122 /// \brief Build a new FieldDecl and check its well-formedness.
13124 /// This routine builds a new FieldDecl given the fields name, type,
13125 /// record, etc. \p PrevDecl should refer to any previous declaration
13126 /// with the same name and in the same scope as the field to be
13129 /// \returns a new FieldDecl.
13131 /// \todo The Declarator argument is a hack. It will be removed once
13132 FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T,
13133 TypeSourceInfo *TInfo,
13134 RecordDecl *Record, SourceLocation Loc,
13135 bool Mutable, Expr *BitWidth,
13136 InClassInitStyle InitStyle,
13137 SourceLocation TSSL,
13138 AccessSpecifier AS, NamedDecl *PrevDecl,
13140 IdentifierInfo *II = Name.getAsIdentifierInfo();
13141 bool InvalidDecl = false;
13142 if (D) InvalidDecl = D->isInvalidType();
13144 // If we receive a broken type, recover by assuming 'int' and
13145 // marking this declaration as invalid.
13147 InvalidDecl = true;
13151 QualType EltTy = Context.getBaseElementType(T);
13152 if (!EltTy->isDependentType()) {
13153 if (RequireCompleteType(Loc, EltTy, diag::err_field_incomplete)) {
13154 // Fields of incomplete type force their record to be invalid.
13155 Record->setInvalidDecl();
13156 InvalidDecl = true;
13159 EltTy->isIncompleteType(&Def);
13160 if (Def && Def->isInvalidDecl()) {
13161 Record->setInvalidDecl();
13162 InvalidDecl = true;
13167 // OpenCL v1.2 s6.9.c: bitfields are not supported.
13168 if (BitWidth && getLangOpts().OpenCL) {
13169 Diag(Loc, diag::err_opencl_bitfields);
13170 InvalidDecl = true;
13173 // C99 6.7.2.1p8: A member of a structure or union may have any type other
13174 // than a variably modified type.
13175 if (!InvalidDecl && T->isVariablyModifiedType()) {
13176 bool SizeIsNegative;
13177 llvm::APSInt Oversized;
13179 TypeSourceInfo *FixedTInfo =
13180 TryToFixInvalidVariablyModifiedTypeSourceInfo(TInfo, Context,
13184 Diag(Loc, diag::warn_illegal_constant_array_size);
13185 TInfo = FixedTInfo;
13186 T = FixedTInfo->getType();
13188 if (SizeIsNegative)
13189 Diag(Loc, diag::err_typecheck_negative_array_size);
13190 else if (Oversized.getBoolValue())
13191 Diag(Loc, diag::err_array_too_large)
13192 << Oversized.toString(10);
13194 Diag(Loc, diag::err_typecheck_field_variable_size);
13195 InvalidDecl = true;
13199 // Fields can not have abstract class types
13200 if (!InvalidDecl && RequireNonAbstractType(Loc, T,
13201 diag::err_abstract_type_in_decl,
13202 AbstractFieldType))
13203 InvalidDecl = true;
13205 bool ZeroWidth = false;
13207 BitWidth = nullptr;
13208 // If this is declared as a bit-field, check the bit-field.
13210 BitWidth = VerifyBitField(Loc, II, T, Record->isMsStruct(Context), BitWidth,
13213 InvalidDecl = true;
13214 BitWidth = nullptr;
13219 // Check that 'mutable' is consistent with the type of the declaration.
13220 if (!InvalidDecl && Mutable) {
13221 unsigned DiagID = 0;
13222 if (T->isReferenceType())
13223 DiagID = getLangOpts().MSVCCompat ? diag::ext_mutable_reference
13224 : diag::err_mutable_reference;
13225 else if (T.isConstQualified())
13226 DiagID = diag::err_mutable_const;
13229 SourceLocation ErrLoc = Loc;
13230 if (D && D->getDeclSpec().getStorageClassSpecLoc().isValid())
13231 ErrLoc = D->getDeclSpec().getStorageClassSpecLoc();
13232 Diag(ErrLoc, DiagID);
13233 if (DiagID != diag::ext_mutable_reference) {
13235 InvalidDecl = true;
13240 // C++11 [class.union]p8 (DR1460):
13241 // At most one variant member of a union may have a
13242 // brace-or-equal-initializer.
13243 if (InitStyle != ICIS_NoInit)
13244 checkDuplicateDefaultInit(*this, cast<CXXRecordDecl>(Record), Loc);
13246 FieldDecl *NewFD = FieldDecl::Create(Context, Record, TSSL, Loc, II, T, TInfo,
13247 BitWidth, Mutable, InitStyle);
13249 NewFD->setInvalidDecl();
13251 if (PrevDecl && !isa<TagDecl>(PrevDecl)) {
13252 Diag(Loc, diag::err_duplicate_member) << II;
13253 Diag(PrevDecl->getLocation(), diag::note_previous_declaration);
13254 NewFD->setInvalidDecl();
13257 if (!InvalidDecl && getLangOpts().CPlusPlus) {
13258 if (Record->isUnion()) {
13259 if (const RecordType *RT = EltTy->getAs<RecordType>()) {
13260 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl());
13261 if (RDecl->getDefinition()) {
13262 // C++ [class.union]p1: An object of a class with a non-trivial
13263 // constructor, a non-trivial copy constructor, a non-trivial
13264 // destructor, or a non-trivial copy assignment operator
13265 // cannot be a member of a union, nor can an array of such
13267 if (CheckNontrivialField(NewFD))
13268 NewFD->setInvalidDecl();
13272 // C++ [class.union]p1: If a union contains a member of reference type,
13273 // the program is ill-formed, except when compiling with MSVC extensions
13275 if (EltTy->isReferenceType()) {
13276 Diag(NewFD->getLocation(), getLangOpts().MicrosoftExt ?
13277 diag::ext_union_member_of_reference_type :
13278 diag::err_union_member_of_reference_type)
13279 << NewFD->getDeclName() << EltTy;
13280 if (!getLangOpts().MicrosoftExt)
13281 NewFD->setInvalidDecl();
13286 // FIXME: We need to pass in the attributes given an AST
13287 // representation, not a parser representation.
13289 // FIXME: The current scope is almost... but not entirely... correct here.
13290 ProcessDeclAttributes(getCurScope(), NewFD, *D);
13292 if (NewFD->hasAttrs())
13293 CheckAlignasUnderalignment(NewFD);
13296 // In auto-retain/release, infer strong retension for fields of
13297 // retainable type.
13298 if (getLangOpts().ObjCAutoRefCount && inferObjCARCLifetime(NewFD))
13299 NewFD->setInvalidDecl();
13301 if (T.isObjCGCWeak())
13302 Diag(Loc, diag::warn_attribute_weak_on_field);
13304 NewFD->setAccess(AS);
13308 bool Sema::CheckNontrivialField(FieldDecl *FD) {
13310 assert(getLangOpts().CPlusPlus && "valid check only for C++");
13312 if (FD->isInvalidDecl() || FD->getType()->isDependentType())
13315 QualType EltTy = Context.getBaseElementType(FD->getType());
13316 if (const RecordType *RT = EltTy->getAs<RecordType>()) {
13317 CXXRecordDecl *RDecl = cast<CXXRecordDecl>(RT->getDecl());
13318 if (RDecl->getDefinition()) {
13319 // We check for copy constructors before constructors
13320 // because otherwise we'll never get complaints about
13321 // copy constructors.
13323 CXXSpecialMember member = CXXInvalid;
13324 // We're required to check for any non-trivial constructors. Since the
13325 // implicit default constructor is suppressed if there are any
13326 // user-declared constructors, we just need to check that there is a
13327 // trivial default constructor and a trivial copy constructor. (We don't
13328 // worry about move constructors here, since this is a C++98 check.)
13329 if (RDecl->hasNonTrivialCopyConstructor())
13330 member = CXXCopyConstructor;
13331 else if (!RDecl->hasTrivialDefaultConstructor())
13332 member = CXXDefaultConstructor;
13333 else if (RDecl->hasNonTrivialCopyAssignment())
13334 member = CXXCopyAssignment;
13335 else if (RDecl->hasNonTrivialDestructor())
13336 member = CXXDestructor;
13338 if (member != CXXInvalid) {
13339 if (!getLangOpts().CPlusPlus11 &&
13340 getLangOpts().ObjCAutoRefCount && RDecl->hasObjectMember()) {
13341 // Objective-C++ ARC: it is an error to have a non-trivial field of
13342 // a union. However, system headers in Objective-C programs
13343 // occasionally have Objective-C lifetime objects within unions,
13344 // and rather than cause the program to fail, we make those
13345 // members unavailable.
13346 SourceLocation Loc = FD->getLocation();
13347 if (getSourceManager().isInSystemHeader(Loc)) {
13348 if (!FD->hasAttr<UnavailableAttr>())
13349 FD->addAttr(UnavailableAttr::CreateImplicit(Context, "",
13350 UnavailableAttr::IR_ARCFieldWithOwnership, Loc));
13355 Diag(FD->getLocation(), getLangOpts().CPlusPlus11 ?
13356 diag::warn_cxx98_compat_nontrivial_union_or_anon_struct_member :
13357 diag::err_illegal_union_or_anon_struct_member)
13358 << FD->getParent()->isUnion() << FD->getDeclName() << member;
13359 DiagnoseNontrivial(RDecl, member);
13360 return !getLangOpts().CPlusPlus11;
13368 /// TranslateIvarVisibility - Translate visibility from a token ID to an
13369 /// AST enum value.
13370 static ObjCIvarDecl::AccessControl
13371 TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) {
13372 switch (ivarVisibility) {
13373 default: llvm_unreachable("Unknown visitibility kind");
13374 case tok::objc_private: return ObjCIvarDecl::Private;
13375 case tok::objc_public: return ObjCIvarDecl::Public;
13376 case tok::objc_protected: return ObjCIvarDecl::Protected;
13377 case tok::objc_package: return ObjCIvarDecl::Package;
13381 /// ActOnIvar - Each ivar field of an objective-c class is passed into this
13382 /// in order to create an IvarDecl object for it.
13383 Decl *Sema::ActOnIvar(Scope *S,
13384 SourceLocation DeclStart,
13385 Declarator &D, Expr *BitfieldWidth,
13386 tok::ObjCKeywordKind Visibility) {
13388 IdentifierInfo *II = D.getIdentifier();
13389 Expr *BitWidth = (Expr*)BitfieldWidth;
13390 SourceLocation Loc = DeclStart;
13391 if (II) Loc = D.getIdentifierLoc();
13393 // FIXME: Unnamed fields can be handled in various different ways, for
13394 // example, unnamed unions inject all members into the struct namespace!
13396 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S);
13397 QualType T = TInfo->getType();
13400 // 6.7.2.1p3, 6.7.2.1p4
13401 BitWidth = VerifyBitField(Loc, II, T, /*IsMsStruct*/false, BitWidth).get();
13403 D.setInvalidType();
13410 if (T->isReferenceType()) {
13411 Diag(Loc, diag::err_ivar_reference_type);
13412 D.setInvalidType();
13414 // C99 6.7.2.1p8: A member of a structure or union may have any type other
13415 // than a variably modified type.
13416 else if (T->isVariablyModifiedType()) {
13417 Diag(Loc, diag::err_typecheck_ivar_variable_size);
13418 D.setInvalidType();
13421 // Get the visibility (access control) for this ivar.
13422 ObjCIvarDecl::AccessControl ac =
13423 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility)
13424 : ObjCIvarDecl::None;
13425 // Must set ivar's DeclContext to its enclosing interface.
13426 ObjCContainerDecl *EnclosingDecl = cast<ObjCContainerDecl>(CurContext);
13427 if (!EnclosingDecl || EnclosingDecl->isInvalidDecl())
13429 ObjCContainerDecl *EnclosingContext;
13430 if (ObjCImplementationDecl *IMPDecl =
13431 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) {
13432 if (LangOpts.ObjCRuntime.isFragile()) {
13433 // Case of ivar declared in an implementation. Context is that of its class.
13434 EnclosingContext = IMPDecl->getClassInterface();
13435 assert(EnclosingContext && "Implementation has no class interface!");
13438 EnclosingContext = EnclosingDecl;
13440 if (ObjCCategoryDecl *CDecl =
13441 dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) {
13442 if (LangOpts.ObjCRuntime.isFragile() || !CDecl->IsClassExtension()) {
13443 Diag(Loc, diag::err_misplaced_ivar) << CDecl->IsClassExtension();
13447 EnclosingContext = EnclosingDecl;
13450 // Construct the decl.
13451 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, EnclosingContext,
13452 DeclStart, Loc, II, T,
13453 TInfo, ac, (Expr *)BitfieldWidth);
13456 NamedDecl *PrevDecl = LookupSingleName(S, II, Loc, LookupMemberName,
13458 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S)
13459 && !isa<TagDecl>(PrevDecl)) {
13460 Diag(Loc, diag::err_duplicate_member) << II;
13461 Diag(PrevDecl->getLocation(), diag::note_previous_declaration);
13462 NewID->setInvalidDecl();
13466 // Process attributes attached to the ivar.
13467 ProcessDeclAttributes(S, NewID, D);
13469 if (D.isInvalidType())
13470 NewID->setInvalidDecl();
13472 // In ARC, infer 'retaining' for ivars of retainable type.
13473 if (getLangOpts().ObjCAutoRefCount && inferObjCARCLifetime(NewID))
13474 NewID->setInvalidDecl();
13476 if (D.getDeclSpec().isModulePrivateSpecified())
13477 NewID->setModulePrivate();
13480 // FIXME: When interfaces are DeclContexts, we'll need to add
13481 // these to the interface.
13483 IdResolver.AddDecl(NewID);
13486 if (LangOpts.ObjCRuntime.isNonFragile() &&
13487 !NewID->isInvalidDecl() && isa<ObjCInterfaceDecl>(EnclosingDecl))
13488 Diag(Loc, diag::warn_ivars_in_interface);
13493 /// ActOnLastBitfield - This routine handles synthesized bitfields rules for
13494 /// class and class extensions. For every class \@interface and class
13495 /// extension \@interface, if the last ivar is a bitfield of any type,
13496 /// then add an implicit `char :0` ivar to the end of that interface.
13497 void Sema::ActOnLastBitfield(SourceLocation DeclLoc,
13498 SmallVectorImpl<Decl *> &AllIvarDecls) {
13499 if (LangOpts.ObjCRuntime.isFragile() || AllIvarDecls.empty())
13502 Decl *ivarDecl = AllIvarDecls[AllIvarDecls.size()-1];
13503 ObjCIvarDecl *Ivar = cast<ObjCIvarDecl>(ivarDecl);
13505 if (!Ivar->isBitField() || Ivar->getBitWidthValue(Context) == 0)
13507 ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(CurContext);
13509 if (ObjCCategoryDecl *CD = dyn_cast<ObjCCategoryDecl>(CurContext)) {
13510 if (!CD->IsClassExtension())
13513 // No need to add this to end of @implementation.
13517 // All conditions are met. Add a new bitfield to the tail end of ivars.
13518 llvm::APInt Zero(Context.getTypeSize(Context.IntTy), 0);
13519 Expr * BW = IntegerLiteral::Create(Context, Zero, Context.IntTy, DeclLoc);
13521 Ivar = ObjCIvarDecl::Create(Context, cast<ObjCContainerDecl>(CurContext),
13522 DeclLoc, DeclLoc, nullptr,
13524 Context.getTrivialTypeSourceInfo(Context.CharTy,
13526 ObjCIvarDecl::Private, BW,
13528 AllIvarDecls.push_back(Ivar);
13531 void Sema::ActOnFields(Scope *S, SourceLocation RecLoc, Decl *EnclosingDecl,
13532 ArrayRef<Decl *> Fields, SourceLocation LBrac,
13533 SourceLocation RBrac, AttributeList *Attr) {
13534 assert(EnclosingDecl && "missing record or interface decl");
13536 // If this is an Objective-C @implementation or category and we have
13537 // new fields here we should reset the layout of the interface since
13538 // it will now change.
13539 if (!Fields.empty() && isa<ObjCContainerDecl>(EnclosingDecl)) {
13540 ObjCContainerDecl *DC = cast<ObjCContainerDecl>(EnclosingDecl);
13541 switch (DC->getKind()) {
13543 case Decl::ObjCCategory:
13544 Context.ResetObjCLayout(cast<ObjCCategoryDecl>(DC)->getClassInterface());
13546 case Decl::ObjCImplementation:
13548 ResetObjCLayout(cast<ObjCImplementationDecl>(DC)->getClassInterface());
13553 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl);
13555 // Start counting up the number of named members; make sure to include
13556 // members of anonymous structs and unions in the total.
13557 unsigned NumNamedMembers = 0;
13559 for (const auto *I : Record->decls()) {
13560 if (const auto *IFD = dyn_cast<IndirectFieldDecl>(I))
13561 if (IFD->getDeclName())
13566 // Verify that all the fields are okay.
13567 SmallVector<FieldDecl*, 32> RecFields;
13569 bool ARCErrReported = false;
13570 for (ArrayRef<Decl *>::iterator i = Fields.begin(), end = Fields.end();
13572 FieldDecl *FD = cast<FieldDecl>(*i);
13574 // Get the type for the field.
13575 const Type *FDTy = FD->getType().getTypePtr();
13577 if (!FD->isAnonymousStructOrUnion()) {
13578 // Remember all fields written by the user.
13579 RecFields.push_back(FD);
13582 // If the field is already invalid for some reason, don't emit more
13583 // diagnostics about it.
13584 if (FD->isInvalidDecl()) {
13585 EnclosingDecl->setInvalidDecl();
13590 // A structure or union shall not contain a member with
13591 // incomplete or function type (hence, a structure shall not
13592 // contain an instance of itself, but may contain a pointer to
13593 // an instance of itself), except that the last member of a
13594 // structure with more than one named member may have incomplete
13595 // array type; such a structure (and any union containing,
13596 // possibly recursively, a member that is such a structure)
13597 // shall not be a member of a structure or an element of an
13599 if (FDTy->isFunctionType()) {
13600 // Field declared as a function.
13601 Diag(FD->getLocation(), diag::err_field_declared_as_function)
13602 << FD->getDeclName();
13603 FD->setInvalidDecl();
13604 EnclosingDecl->setInvalidDecl();
13606 } else if (FDTy->isIncompleteArrayType() && Record &&
13607 ((i + 1 == Fields.end() && !Record->isUnion()) ||
13608 ((getLangOpts().MicrosoftExt ||
13609 getLangOpts().CPlusPlus) &&
13610 (i + 1 == Fields.end() || Record->isUnion())))) {
13611 // Flexible array member.
13612 // Microsoft and g++ is more permissive regarding flexible array.
13613 // It will accept flexible array in union and also
13614 // as the sole element of a struct/class.
13615 unsigned DiagID = 0;
13616 if (Record->isUnion())
13617 DiagID = getLangOpts().MicrosoftExt
13618 ? diag::ext_flexible_array_union_ms
13619 : getLangOpts().CPlusPlus
13620 ? diag::ext_flexible_array_union_gnu
13621 : diag::err_flexible_array_union;
13622 else if (Fields.size() == 1)
13623 DiagID = getLangOpts().MicrosoftExt
13624 ? diag::ext_flexible_array_empty_aggregate_ms
13625 : getLangOpts().CPlusPlus
13626 ? diag::ext_flexible_array_empty_aggregate_gnu
13627 : NumNamedMembers < 1
13628 ? diag::err_flexible_array_empty_aggregate
13632 Diag(FD->getLocation(), DiagID) << FD->getDeclName()
13633 << Record->getTagKind();
13634 // While the layout of types that contain virtual bases is not specified
13635 // by the C++ standard, both the Itanium and Microsoft C++ ABIs place
13636 // virtual bases after the derived members. This would make a flexible
13637 // array member declared at the end of an object not adjacent to the end
13639 if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(Record))
13640 if (RD->getNumVBases() != 0)
13641 Diag(FD->getLocation(), diag::err_flexible_array_virtual_base)
13642 << FD->getDeclName() << Record->getTagKind();
13643 if (!getLangOpts().C99)
13644 Diag(FD->getLocation(), diag::ext_c99_flexible_array_member)
13645 << FD->getDeclName() << Record->getTagKind();
13647 // If the element type has a non-trivial destructor, we would not
13648 // implicitly destroy the elements, so disallow it for now.
13650 // FIXME: GCC allows this. We should probably either implicitly delete
13651 // the destructor of the containing class, or just allow this.
13652 QualType BaseElem = Context.getBaseElementType(FD->getType());
13653 if (!BaseElem->isDependentType() && BaseElem.isDestructedType()) {
13654 Diag(FD->getLocation(), diag::err_flexible_array_has_nontrivial_dtor)
13655 << FD->getDeclName() << FD->getType();
13656 FD->setInvalidDecl();
13657 EnclosingDecl->setInvalidDecl();
13660 // Okay, we have a legal flexible array member at the end of the struct.
13661 Record->setHasFlexibleArrayMember(true);
13662 } else if (!FDTy->isDependentType() &&
13663 RequireCompleteType(FD->getLocation(), FD->getType(),
13664 diag::err_field_incomplete)) {
13666 FD->setInvalidDecl();
13667 EnclosingDecl->setInvalidDecl();
13669 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) {
13670 if (Record && FDTTy->getDecl()->hasFlexibleArrayMember()) {
13671 // A type which contains a flexible array member is considered to be a
13672 // flexible array member.
13673 Record->setHasFlexibleArrayMember(true);
13674 if (!Record->isUnion()) {
13675 // If this is a struct/class and this is not the last element, reject
13676 // it. Note that GCC supports variable sized arrays in the middle of
13678 if (i + 1 != Fields.end())
13679 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct)
13680 << FD->getDeclName() << FD->getType();
13682 // We support flexible arrays at the end of structs in
13683 // other structs as an extension.
13684 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct)
13685 << FD->getDeclName();
13689 if (isa<ObjCContainerDecl>(EnclosingDecl) &&
13690 RequireNonAbstractType(FD->getLocation(), FD->getType(),
13691 diag::err_abstract_type_in_decl,
13692 AbstractIvarType)) {
13693 // Ivars can not have abstract class types
13694 FD->setInvalidDecl();
13696 if (Record && FDTTy->getDecl()->hasObjectMember())
13697 Record->setHasObjectMember(true);
13698 if (Record && FDTTy->getDecl()->hasVolatileMember())
13699 Record->setHasVolatileMember(true);
13700 } else if (FDTy->isObjCObjectType()) {
13701 /// A field cannot be an Objective-c object
13702 Diag(FD->getLocation(), diag::err_statically_allocated_object)
13703 << FixItHint::CreateInsertion(FD->getLocation(), "*");
13704 QualType T = Context.getObjCObjectPointerType(FD->getType());
13706 } else if (getLangOpts().ObjCAutoRefCount && Record && !ARCErrReported &&
13707 (!getLangOpts().CPlusPlus || Record->isUnion())) {
13708 // It's an error in ARC if a field has lifetime.
13709 // We don't want to report this in a system header, though,
13710 // so we just make the field unavailable.
13711 // FIXME: that's really not sufficient; we need to make the type
13712 // itself invalid to, say, initialize or copy.
13713 QualType T = FD->getType();
13714 Qualifiers::ObjCLifetime lifetime = T.getObjCLifetime();
13715 if (lifetime && lifetime != Qualifiers::OCL_ExplicitNone) {
13716 SourceLocation loc = FD->getLocation();
13717 if (getSourceManager().isInSystemHeader(loc)) {
13718 if (!FD->hasAttr<UnavailableAttr>()) {
13719 FD->addAttr(UnavailableAttr::CreateImplicit(Context, "",
13720 UnavailableAttr::IR_ARCFieldWithOwnership, loc));
13723 Diag(FD->getLocation(), diag::err_arc_objc_object_in_tag)
13724 << T->isBlockPointerType() << Record->getTagKind();
13726 ARCErrReported = true;
13728 } else if (getLangOpts().ObjC1 &&
13729 getLangOpts().getGC() != LangOptions::NonGC &&
13730 Record && !Record->hasObjectMember()) {
13731 if (FD->getType()->isObjCObjectPointerType() ||
13732 FD->getType().isObjCGCStrong())
13733 Record->setHasObjectMember(true);
13734 else if (Context.getAsArrayType(FD->getType())) {
13735 QualType BaseType = Context.getBaseElementType(FD->getType());
13736 if (BaseType->isRecordType() &&
13737 BaseType->getAs<RecordType>()->getDecl()->hasObjectMember())
13738 Record->setHasObjectMember(true);
13739 else if (BaseType->isObjCObjectPointerType() ||
13740 BaseType.isObjCGCStrong())
13741 Record->setHasObjectMember(true);
13744 if (Record && FD->getType().isVolatileQualified())
13745 Record->setHasVolatileMember(true);
13746 // Keep track of the number of named members.
13747 if (FD->getIdentifier())
13751 // Okay, we successfully defined 'Record'.
13753 bool Completed = false;
13754 if (CXXRecordDecl *CXXRecord = dyn_cast<CXXRecordDecl>(Record)) {
13755 if (!CXXRecord->isInvalidDecl()) {
13756 // Set access bits correctly on the directly-declared conversions.
13757 for (CXXRecordDecl::conversion_iterator
13758 I = CXXRecord->conversion_begin(),
13759 E = CXXRecord->conversion_end(); I != E; ++I)
13760 I.setAccess((*I)->getAccess());
13762 if (!CXXRecord->isDependentType()) {
13763 if (CXXRecord->hasUserDeclaredDestructor()) {
13764 // Adjust user-defined destructor exception spec.
13765 if (getLangOpts().CPlusPlus11)
13766 AdjustDestructorExceptionSpec(CXXRecord,
13767 CXXRecord->getDestructor());
13770 // Add any implicitly-declared members to this class.
13771 AddImplicitlyDeclaredMembersToClass(CXXRecord);
13773 // If we have virtual base classes, we may end up finding multiple
13774 // final overriders for a given virtual function. Check for this
13776 if (CXXRecord->getNumVBases()) {
13777 CXXFinalOverriderMap FinalOverriders;
13778 CXXRecord->getFinalOverriders(FinalOverriders);
13780 for (CXXFinalOverriderMap::iterator M = FinalOverriders.begin(),
13781 MEnd = FinalOverriders.end();
13783 for (OverridingMethods::iterator SO = M->second.begin(),
13784 SOEnd = M->second.end();
13785 SO != SOEnd; ++SO) {
13786 assert(SO->second.size() > 0 &&
13787 "Virtual function without overridding functions?");
13788 if (SO->second.size() == 1)
13791 // C++ [class.virtual]p2:
13792 // In a derived class, if a virtual member function of a base
13793 // class subobject has more than one final overrider the
13794 // program is ill-formed.
13795 Diag(Record->getLocation(), diag::err_multiple_final_overriders)
13796 << (const NamedDecl *)M->first << Record;
13797 Diag(M->first->getLocation(),
13798 diag::note_overridden_virtual_function);
13799 for (OverridingMethods::overriding_iterator
13800 OM = SO->second.begin(),
13801 OMEnd = SO->second.end();
13803 Diag(OM->Method->getLocation(), diag::note_final_overrider)
13804 << (const NamedDecl *)M->first << OM->Method->getParent();
13806 Record->setInvalidDecl();
13809 CXXRecord->completeDefinition(&FinalOverriders);
13817 Record->completeDefinition();
13819 if (Record->hasAttrs()) {
13820 CheckAlignasUnderalignment(Record);
13822 if (const MSInheritanceAttr *IA = Record->getAttr<MSInheritanceAttr>())
13823 checkMSInheritanceAttrOnDefinition(cast<CXXRecordDecl>(Record),
13824 IA->getRange(), IA->getBestCase(),
13825 IA->getSemanticSpelling());
13828 // Check if the structure/union declaration is a type that can have zero
13829 // size in C. For C this is a language extension, for C++ it may cause
13830 // compatibility problems.
13831 bool CheckForZeroSize;
13832 if (!getLangOpts().CPlusPlus) {
13833 CheckForZeroSize = true;
13835 // For C++ filter out types that cannot be referenced in C code.
13836 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record);
13838 CXXRecord->getLexicalDeclContext()->isExternCContext() &&
13839 !CXXRecord->isDependentType() &&
13840 CXXRecord->isCLike();
13842 if (CheckForZeroSize) {
13843 bool ZeroSize = true;
13844 bool IsEmpty = true;
13845 unsigned NonBitFields = 0;
13846 for (RecordDecl::field_iterator I = Record->field_begin(),
13847 E = Record->field_end();
13848 (NonBitFields == 0 || ZeroSize) && I != E; ++I) {
13850 if (I->isUnnamedBitfield()) {
13851 if (I->getBitWidthValue(Context) > 0)
13855 QualType FieldType = I->getType();
13856 if (FieldType->isIncompleteType() ||
13857 !Context.getTypeSizeInChars(FieldType).isZero())
13862 // Empty structs are an extension in C (C99 6.7.2.1p7). They are
13863 // allowed in C++, but warn if its declaration is inside
13864 // extern "C" block.
13866 Diag(RecLoc, getLangOpts().CPlusPlus ?
13867 diag::warn_zero_size_struct_union_in_extern_c :
13868 diag::warn_zero_size_struct_union_compat)
13869 << IsEmpty << Record->isUnion() << (NonBitFields > 1);
13872 // Structs without named members are extension in C (C99 6.7.2.1p7),
13873 // but are accepted by GCC.
13874 if (NonBitFields == 0 && !getLangOpts().CPlusPlus) {
13875 Diag(RecLoc, IsEmpty ? diag::ext_empty_struct_union :
13876 diag::ext_no_named_members_in_struct_union)
13877 << Record->isUnion();
13881 ObjCIvarDecl **ClsFields =
13882 reinterpret_cast<ObjCIvarDecl**>(RecFields.data());
13883 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) {
13884 ID->setEndOfDefinitionLoc(RBrac);
13885 // Add ivar's to class's DeclContext.
13886 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) {
13887 ClsFields[i]->setLexicalDeclContext(ID);
13888 ID->addDecl(ClsFields[i]);
13890 // Must enforce the rule that ivars in the base classes may not be
13892 if (ID->getSuperClass())
13893 DiagnoseDuplicateIvars(ID, ID->getSuperClass());
13894 } else if (ObjCImplementationDecl *IMPDecl =
13895 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) {
13896 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl");
13897 for (unsigned I = 0, N = RecFields.size(); I != N; ++I)
13898 // Ivar declared in @implementation never belongs to the implementation.
13899 // Only it is in implementation's lexical context.
13900 ClsFields[I]->setLexicalDeclContext(IMPDecl);
13901 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac);
13902 IMPDecl->setIvarLBraceLoc(LBrac);
13903 IMPDecl->setIvarRBraceLoc(RBrac);
13904 } else if (ObjCCategoryDecl *CDecl =
13905 dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) {
13906 // case of ivars in class extension; all other cases have been
13907 // reported as errors elsewhere.
13908 // FIXME. Class extension does not have a LocEnd field.
13909 // CDecl->setLocEnd(RBrac);
13910 // Add ivar's to class extension's DeclContext.
13911 // Diagnose redeclaration of private ivars.
13912 ObjCInterfaceDecl *IDecl = CDecl->getClassInterface();
13913 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) {
13915 if (const ObjCIvarDecl *ClsIvar =
13916 IDecl->getIvarDecl(ClsFields[i]->getIdentifier())) {
13917 Diag(ClsFields[i]->getLocation(),
13918 diag::err_duplicate_ivar_declaration);
13919 Diag(ClsIvar->getLocation(), diag::note_previous_definition);
13922 for (const auto *Ext : IDecl->known_extensions()) {
13923 if (const ObjCIvarDecl *ClsExtIvar
13924 = Ext->getIvarDecl(ClsFields[i]->getIdentifier())) {
13925 Diag(ClsFields[i]->getLocation(),
13926 diag::err_duplicate_ivar_declaration);
13927 Diag(ClsExtIvar->getLocation(), diag::note_previous_definition);
13932 ClsFields[i]->setLexicalDeclContext(CDecl);
13933 CDecl->addDecl(ClsFields[i]);
13935 CDecl->setIvarLBraceLoc(LBrac);
13936 CDecl->setIvarRBraceLoc(RBrac);
13941 ProcessDeclAttributeList(S, Record, Attr);
13944 /// \brief Determine whether the given integral value is representable within
13945 /// the given type T.
13946 static bool isRepresentableIntegerValue(ASTContext &Context,
13947 llvm::APSInt &Value,
13949 assert(T->isIntegralType(Context) && "Integral type required!");
13950 unsigned BitWidth = Context.getIntWidth(T);
13952 if (Value.isUnsigned() || Value.isNonNegative()) {
13953 if (T->isSignedIntegerOrEnumerationType())
13955 return Value.getActiveBits() <= BitWidth;
13957 return Value.getMinSignedBits() <= BitWidth;
13960 // \brief Given an integral type, return the next larger integral type
13961 // (or a NULL type of no such type exists).
13962 static QualType getNextLargerIntegralType(ASTContext &Context, QualType T) {
13963 // FIXME: Int128/UInt128 support, which also needs to be introduced into
13964 // enum checking below.
13965 assert(T->isIntegralType(Context) && "Integral type required!");
13966 const unsigned NumTypes = 4;
13967 QualType SignedIntegralTypes[NumTypes] = {
13968 Context.ShortTy, Context.IntTy, Context.LongTy, Context.LongLongTy
13970 QualType UnsignedIntegralTypes[NumTypes] = {
13971 Context.UnsignedShortTy, Context.UnsignedIntTy, Context.UnsignedLongTy,
13972 Context.UnsignedLongLongTy
13975 unsigned BitWidth = Context.getTypeSize(T);
13976 QualType *Types = T->isSignedIntegerOrEnumerationType()? SignedIntegralTypes
13977 : UnsignedIntegralTypes;
13978 for (unsigned I = 0; I != NumTypes; ++I)
13979 if (Context.getTypeSize(Types[I]) > BitWidth)
13985 EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum,
13986 EnumConstantDecl *LastEnumConst,
13987 SourceLocation IdLoc,
13988 IdentifierInfo *Id,
13990 unsigned IntWidth = Context.getTargetInfo().getIntWidth();
13991 llvm::APSInt EnumVal(IntWidth);
13994 if (Val && DiagnoseUnexpandedParameterPack(Val, UPPC_EnumeratorValue))
13998 Val = DefaultLvalueConversion(Val).get();
14001 if (Enum->isDependentType() || Val->isTypeDependent())
14002 EltTy = Context.DependentTy;
14004 SourceLocation ExpLoc;
14005 if (getLangOpts().CPlusPlus11 && Enum->isFixed() &&
14006 !getLangOpts().MSVCCompat) {
14007 // C++11 [dcl.enum]p5: If the underlying type is fixed, [...] the
14008 // constant-expression in the enumerator-definition shall be a converted
14009 // constant expression of the underlying type.
14010 EltTy = Enum->getIntegerType();
14011 ExprResult Converted =
14012 CheckConvertedConstantExpression(Val, EltTy, EnumVal,
14014 if (Converted.isInvalid())
14017 Val = Converted.get();
14018 } else if (!Val->isValueDependent() &&
14019 !(Val = VerifyIntegerConstantExpression(Val,
14020 &EnumVal).get())) {
14021 // C99 6.7.2.2p2: Make sure we have an integer constant expression.
14023 if (Enum->isFixed()) {
14024 EltTy = Enum->getIntegerType();
14026 // In Obj-C and Microsoft mode, require the enumeration value to be
14027 // representable in the underlying type of the enumeration. In C++11,
14028 // we perform a non-narrowing conversion as part of converted constant
14029 // expression checking.
14030 if (!isRepresentableIntegerValue(Context, EnumVal, EltTy)) {
14031 if (getLangOpts().MSVCCompat) {
14032 Diag(IdLoc, diag::ext_enumerator_too_large) << EltTy;
14033 Val = ImpCastExprToType(Val, EltTy, CK_IntegralCast).get();
14035 Diag(IdLoc, diag::err_enumerator_too_large) << EltTy;
14037 Val = ImpCastExprToType(Val, EltTy, CK_IntegralCast).get();
14038 } else if (getLangOpts().CPlusPlus) {
14039 // C++11 [dcl.enum]p5:
14040 // If the underlying type is not fixed, the type of each enumerator
14041 // is the type of its initializing value:
14042 // - If an initializer is specified for an enumerator, the
14043 // initializing value has the same type as the expression.
14044 EltTy = Val->getType();
14047 // The expression that defines the value of an enumeration constant
14048 // shall be an integer constant expression that has a value
14049 // representable as an int.
14051 // Complain if the value is not representable in an int.
14052 if (!isRepresentableIntegerValue(Context, EnumVal, Context.IntTy))
14053 Diag(IdLoc, diag::ext_enum_value_not_int)
14054 << EnumVal.toString(10) << Val->getSourceRange()
14055 << (EnumVal.isUnsigned() || EnumVal.isNonNegative());
14056 else if (!Context.hasSameType(Val->getType(), Context.IntTy)) {
14057 // Force the type of the expression to 'int'.
14058 Val = ImpCastExprToType(Val, Context.IntTy, CK_IntegralCast).get();
14060 EltTy = Val->getType();
14067 if (Enum->isDependentType())
14068 EltTy = Context.DependentTy;
14069 else if (!LastEnumConst) {
14070 // C++0x [dcl.enum]p5:
14071 // If the underlying type is not fixed, the type of each enumerator
14072 // is the type of its initializing value:
14073 // - If no initializer is specified for the first enumerator, the
14074 // initializing value has an unspecified integral type.
14076 // GCC uses 'int' for its unspecified integral type, as does
14078 if (Enum->isFixed()) {
14079 EltTy = Enum->getIntegerType();
14082 EltTy = Context.IntTy;
14085 // Assign the last value + 1.
14086 EnumVal = LastEnumConst->getInitVal();
14088 EltTy = LastEnumConst->getType();
14090 // Check for overflow on increment.
14091 if (EnumVal < LastEnumConst->getInitVal()) {
14092 // C++0x [dcl.enum]p5:
14093 // If the underlying type is not fixed, the type of each enumerator
14094 // is the type of its initializing value:
14096 // - Otherwise the type of the initializing value is the same as
14097 // the type of the initializing value of the preceding enumerator
14098 // unless the incremented value is not representable in that type,
14099 // in which case the type is an unspecified integral type
14100 // sufficient to contain the incremented value. If no such type
14101 // exists, the program is ill-formed.
14102 QualType T = getNextLargerIntegralType(Context, EltTy);
14103 if (T.isNull() || Enum->isFixed()) {
14104 // There is no integral type larger enough to represent this
14105 // value. Complain, then allow the value to wrap around.
14106 EnumVal = LastEnumConst->getInitVal();
14107 EnumVal = EnumVal.zext(EnumVal.getBitWidth() * 2);
14109 if (Enum->isFixed())
14110 // When the underlying type is fixed, this is ill-formed.
14111 Diag(IdLoc, diag::err_enumerator_wrapped)
14112 << EnumVal.toString(10)
14115 Diag(IdLoc, diag::ext_enumerator_increment_too_large)
14116 << EnumVal.toString(10);
14121 // Retrieve the last enumerator's value, extent that type to the
14122 // type that is supposed to be large enough to represent the incremented
14123 // value, then increment.
14124 EnumVal = LastEnumConst->getInitVal();
14125 EnumVal.setIsSigned(EltTy->isSignedIntegerOrEnumerationType());
14126 EnumVal = EnumVal.zextOrTrunc(Context.getIntWidth(EltTy));
14129 // If we're not in C++, diagnose the overflow of enumerator values,
14130 // which in C99 means that the enumerator value is not representable in
14131 // an int (C99 6.7.2.2p2). However, we support GCC's extension that
14132 // permits enumerator values that are representable in some larger
14134 if (!getLangOpts().CPlusPlus && !T.isNull())
14135 Diag(IdLoc, diag::warn_enum_value_overflow);
14136 } else if (!getLangOpts().CPlusPlus &&
14137 !isRepresentableIntegerValue(Context, EnumVal, EltTy)) {
14138 // Enforce C99 6.7.2.2p2 even when we compute the next value.
14139 Diag(IdLoc, diag::ext_enum_value_not_int)
14140 << EnumVal.toString(10) << 1;
14145 if (!EltTy->isDependentType()) {
14146 // Make the enumerator value match the signedness and size of the
14147 // enumerator's type.
14148 EnumVal = EnumVal.extOrTrunc(Context.getIntWidth(EltTy));
14149 EnumVal.setIsSigned(EltTy->isSignedIntegerOrEnumerationType());
14152 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy,
14156 Sema::SkipBodyInfo Sema::shouldSkipAnonEnumBody(Scope *S, IdentifierInfo *II,
14157 SourceLocation IILoc) {
14158 if (!(getLangOpts().Modules || getLangOpts().ModulesLocalVisibility) ||
14159 !getLangOpts().CPlusPlus)
14160 return SkipBodyInfo();
14162 // We have an anonymous enum definition. Look up the first enumerator to
14163 // determine if we should merge the definition with an existing one and
14165 NamedDecl *PrevDecl = LookupSingleName(S, II, IILoc, LookupOrdinaryName,
14167 auto *PrevECD = dyn_cast_or_null<EnumConstantDecl>(PrevDecl);
14169 return SkipBodyInfo();
14171 EnumDecl *PrevED = cast<EnumDecl>(PrevECD->getDeclContext());
14173 if (!PrevED->getDeclName() && !hasVisibleDefinition(PrevED, &Hidden)) {
14175 Skip.Previous = Hidden;
14179 return SkipBodyInfo();
14182 Decl *Sema::ActOnEnumConstant(Scope *S, Decl *theEnumDecl, Decl *lastEnumConst,
14183 SourceLocation IdLoc, IdentifierInfo *Id,
14184 AttributeList *Attr,
14185 SourceLocation EqualLoc, Expr *Val) {
14186 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl);
14187 EnumConstantDecl *LastEnumConst =
14188 cast_or_null<EnumConstantDecl>(lastEnumConst);
14190 // The scope passed in may not be a decl scope. Zip up the scope tree until
14191 // we find one that is.
14192 S = getNonFieldDeclScope(S);
14194 // Verify that there isn't already something declared with this name in this
14196 NamedDecl *PrevDecl = LookupSingleName(S, Id, IdLoc, LookupOrdinaryName,
14198 if (PrevDecl && PrevDecl->isTemplateParameter()) {
14199 // Maybe we will complain about the shadowed template parameter.
14200 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl);
14201 // Just pretend that we didn't see the previous declaration.
14202 PrevDecl = nullptr;
14205 // C++ [class.mem]p15:
14206 // If T is the name of a class, then each of the following shall have a name
14207 // different from T:
14208 // - every enumerator of every member of class T that is an unscoped
14210 if (!TheEnumDecl->isScoped())
14211 DiagnoseClassNameShadow(TheEnumDecl->getDeclContext(),
14212 DeclarationNameInfo(Id, IdLoc));
14214 EnumConstantDecl *New =
14215 CheckEnumConstant(TheEnumDecl, LastEnumConst, IdLoc, Id, Val);
14220 // When in C++, we may get a TagDecl with the same name; in this case the
14221 // enum constant will 'hide' the tag.
14222 assert((getLangOpts().CPlusPlus || !isa<TagDecl>(PrevDecl)) &&
14223 "Received TagDecl when not in C++!");
14224 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S) &&
14225 shouldLinkPossiblyHiddenDecl(PrevDecl, New)) {
14226 if (isa<EnumConstantDecl>(PrevDecl))
14227 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id;
14229 Diag(IdLoc, diag::err_redefinition) << Id;
14230 Diag(PrevDecl->getLocation(), diag::note_previous_definition);
14235 // Process attributes.
14236 if (Attr) ProcessDeclAttributeList(S, New, Attr);
14238 // Register this decl in the current scope stack.
14239 New->setAccess(TheEnumDecl->getAccess());
14240 PushOnScopeChains(New, S);
14242 ActOnDocumentableDecl(New);
14247 // Returns true when the enum initial expression does not trigger the
14248 // duplicate enum warning. A few common cases are exempted as follows:
14249 // Element2 = Element1
14250 // Element2 = Element1 + 1
14251 // Element2 = Element1 - 1
14252 // Where Element2 and Element1 are from the same enum.
14253 static bool ValidDuplicateEnum(EnumConstantDecl *ECD, EnumDecl *Enum) {
14254 Expr *InitExpr = ECD->getInitExpr();
14257 InitExpr = InitExpr->IgnoreImpCasts();
14259 if (BinaryOperator *BO = dyn_cast<BinaryOperator>(InitExpr)) {
14260 if (!BO->isAdditiveOp())
14262 IntegerLiteral *IL = dyn_cast<IntegerLiteral>(BO->getRHS());
14265 if (IL->getValue() != 1)
14268 InitExpr = BO->getLHS();
14271 // This checks if the elements are from the same enum.
14272 DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(InitExpr);
14276 EnumConstantDecl *EnumConstant = dyn_cast<EnumConstantDecl>(DRE->getDecl());
14280 if (cast<EnumDecl>(TagDecl::castFromDeclContext(ECD->getDeclContext())) !=
14290 bool isTombstoneOrEmptyKey;
14291 DupKey(int64_t val, bool isTombstoneOrEmptyKey)
14292 : val(val), isTombstoneOrEmptyKey(isTombstoneOrEmptyKey) {}
14295 static DupKey GetDupKey(const llvm::APSInt& Val) {
14296 return DupKey(Val.isSigned() ? Val.getSExtValue() : Val.getZExtValue(),
14300 struct DenseMapInfoDupKey {
14301 static DupKey getEmptyKey() { return DupKey(0, true); }
14302 static DupKey getTombstoneKey() { return DupKey(1, true); }
14303 static unsigned getHashValue(const DupKey Key) {
14304 return (unsigned)(Key.val * 37);
14306 static bool isEqual(const DupKey& LHS, const DupKey& RHS) {
14307 return LHS.isTombstoneOrEmptyKey == RHS.isTombstoneOrEmptyKey &&
14308 LHS.val == RHS.val;
14311 } // end anonymous namespace
14313 // Emits a warning when an element is implicitly set a value that
14314 // a previous element has already been set to.
14315 static void CheckForDuplicateEnumValues(Sema &S, ArrayRef<Decl *> Elements,
14317 QualType EnumType) {
14318 if (S.Diags.isIgnored(diag::warn_duplicate_enum_values, Enum->getLocation()))
14320 // Avoid anonymous enums
14321 if (!Enum->getIdentifier())
14324 // Only check for small enums.
14325 if (Enum->getNumPositiveBits() > 63 || Enum->getNumNegativeBits() > 64)
14328 typedef SmallVector<EnumConstantDecl *, 3> ECDVector;
14329 typedef SmallVector<ECDVector *, 3> DuplicatesVector;
14331 typedef llvm::PointerUnion<EnumConstantDecl*, ECDVector*> DeclOrVector;
14332 typedef llvm::DenseMap<DupKey, DeclOrVector, DenseMapInfoDupKey>
14335 DuplicatesVector DupVector;
14336 ValueToVectorMap EnumMap;
14338 // Populate the EnumMap with all values represented by enum constants without
14340 for (unsigned i = 0, e = Elements.size(); i != e; ++i) {
14341 EnumConstantDecl *ECD = cast_or_null<EnumConstantDecl>(Elements[i]);
14343 // Null EnumConstantDecl means a previous diagnostic has been emitted for
14344 // this constant. Skip this enum since it may be ill-formed.
14349 if (ECD->getInitExpr())
14352 DupKey Key = GetDupKey(ECD->getInitVal());
14353 DeclOrVector &Entry = EnumMap[Key];
14355 // First time encountering this value.
14356 if (Entry.isNull())
14360 // Create vectors for any values that has duplicates.
14361 for (unsigned i = 0, e = Elements.size(); i != e; ++i) {
14362 EnumConstantDecl *ECD = cast<EnumConstantDecl>(Elements[i]);
14363 if (!ValidDuplicateEnum(ECD, Enum))
14366 DupKey Key = GetDupKey(ECD->getInitVal());
14368 DeclOrVector& Entry = EnumMap[Key];
14369 if (Entry.isNull())
14372 if (EnumConstantDecl *D = Entry.dyn_cast<EnumConstantDecl*>()) {
14373 // Ensure constants are different.
14377 // Create new vector and push values onto it.
14378 ECDVector *Vec = new ECDVector();
14380 Vec->push_back(ECD);
14382 // Update entry to point to the duplicates vector.
14385 // Store the vector somewhere we can consult later for quick emission of
14387 DupVector.push_back(Vec);
14391 ECDVector *Vec = Entry.get<ECDVector*>();
14392 // Make sure constants are not added more than once.
14393 if (*Vec->begin() == ECD)
14396 Vec->push_back(ECD);
14399 // Emit diagnostics.
14400 for (DuplicatesVector::iterator DupVectorIter = DupVector.begin(),
14401 DupVectorEnd = DupVector.end();
14402 DupVectorIter != DupVectorEnd; ++DupVectorIter) {
14403 ECDVector *Vec = *DupVectorIter;
14404 assert(Vec->size() > 1 && "ECDVector should have at least 2 elements.");
14406 // Emit warning for one enum constant.
14407 ECDVector::iterator I = Vec->begin();
14408 S.Diag((*I)->getLocation(), diag::warn_duplicate_enum_values)
14409 << (*I)->getName() << (*I)->getInitVal().toString(10)
14410 << (*I)->getSourceRange();
14413 // Emit one note for each of the remaining enum constants with
14415 for (ECDVector::iterator E = Vec->end(); I != E; ++I)
14416 S.Diag((*I)->getLocation(), diag::note_duplicate_element)
14417 << (*I)->getName() << (*I)->getInitVal().toString(10)
14418 << (*I)->getSourceRange();
14423 bool Sema::IsValueInFlagEnum(const EnumDecl *ED, const llvm::APInt &Val,
14424 bool AllowMask) const {
14425 assert(ED->hasAttr<FlagEnumAttr>() && "looking for value in non-flag enum");
14426 assert(ED->isCompleteDefinition() && "expected enum definition");
14428 auto R = FlagBitsCache.insert(std::make_pair(ED, llvm::APInt()));
14429 llvm::APInt &FlagBits = R.first->second;
14432 for (auto *E : ED->enumerators()) {
14433 const auto &EVal = E->getInitVal();
14434 // Only single-bit enumerators introduce new flag values.
14435 if (EVal.isPowerOf2())
14436 FlagBits = FlagBits.zextOrSelf(EVal.getBitWidth()) | EVal;
14440 // A value is in a flag enum if either its bits are a subset of the enum's
14441 // flag bits (the first condition) or we are allowing masks and the same is
14442 // true of its complement (the second condition). When masks are allowed, we
14443 // allow the common idiom of ~(enum1 | enum2) to be a valid enum value.
14445 // While it's true that any value could be used as a mask, the assumption is
14446 // that a mask will have all of the insignificant bits set. Anything else is
14447 // likely a logic error.
14448 llvm::APInt FlagMask = ~FlagBits.zextOrTrunc(Val.getBitWidth());
14449 return !(FlagMask & Val) || (AllowMask && !(FlagMask & ~Val));
14452 void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc,
14453 SourceLocation RBraceLoc, Decl *EnumDeclX,
14454 ArrayRef<Decl *> Elements,
14455 Scope *S, AttributeList *Attr) {
14456 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX);
14457 QualType EnumType = Context.getTypeDeclType(Enum);
14460 ProcessDeclAttributeList(S, Enum, Attr);
14462 if (Enum->isDependentType()) {
14463 for (unsigned i = 0, e = Elements.size(); i != e; ++i) {
14464 EnumConstantDecl *ECD =
14465 cast_or_null<EnumConstantDecl>(Elements[i]);
14466 if (!ECD) continue;
14468 ECD->setType(EnumType);
14471 Enum->completeDefinition(Context.DependentTy, Context.DependentTy, 0, 0);
14475 // TODO: If the result value doesn't fit in an int, it must be a long or long
14476 // long value. ISO C does not support this, but GCC does as an extension,
14478 unsigned IntWidth = Context.getTargetInfo().getIntWidth();
14479 unsigned CharWidth = Context.getTargetInfo().getCharWidth();
14480 unsigned ShortWidth = Context.getTargetInfo().getShortWidth();
14482 // Verify that all the values are okay, compute the size of the values, and
14483 // reverse the list.
14484 unsigned NumNegativeBits = 0;
14485 unsigned NumPositiveBits = 0;
14487 // Keep track of whether all elements have type int.
14488 bool AllElementsInt = true;
14490 for (unsigned i = 0, e = Elements.size(); i != e; ++i) {
14491 EnumConstantDecl *ECD =
14492 cast_or_null<EnumConstantDecl>(Elements[i]);
14493 if (!ECD) continue; // Already issued a diagnostic.
14495 const llvm::APSInt &InitVal = ECD->getInitVal();
14497 // Keep track of the size of positive and negative values.
14498 if (InitVal.isUnsigned() || InitVal.isNonNegative())
14499 NumPositiveBits = std::max(NumPositiveBits,
14500 (unsigned)InitVal.getActiveBits());
14502 NumNegativeBits = std::max(NumNegativeBits,
14503 (unsigned)InitVal.getMinSignedBits());
14505 // Keep track of whether every enum element has type int (very commmon).
14506 if (AllElementsInt)
14507 AllElementsInt = ECD->getType() == Context.IntTy;
14510 // Figure out the type that should be used for this enum.
14512 unsigned BestWidth;
14514 // C++0x N3000 [conv.prom]p3:
14515 // An rvalue of an unscoped enumeration type whose underlying
14516 // type is not fixed can be converted to an rvalue of the first
14517 // of the following types that can represent all the values of
14518 // the enumeration: int, unsigned int, long int, unsigned long
14519 // int, long long int, or unsigned long long int.
14521 // An identifier declared as an enumeration constant has type int.
14522 // The C99 rule is modified by a gcc extension
14523 QualType BestPromotionType;
14525 bool Packed = Enum->hasAttr<PackedAttr>();
14526 // -fshort-enums is the equivalent to specifying the packed attribute on all
14527 // enum definitions.
14528 if (LangOpts.ShortEnums)
14531 if (Enum->isFixed()) {
14532 BestType = Enum->getIntegerType();
14533 if (BestType->isPromotableIntegerType())
14534 BestPromotionType = Context.getPromotedIntegerType(BestType);
14536 BestPromotionType = BestType;
14538 BestWidth = Context.getIntWidth(BestType);
14540 else if (NumNegativeBits) {
14541 // If there is a negative value, figure out the smallest integer type (of
14542 // int/long/longlong) that fits.
14543 // If it's packed, check also if it fits a char or a short.
14544 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) {
14545 BestType = Context.SignedCharTy;
14546 BestWidth = CharWidth;
14547 } else if (Packed && NumNegativeBits <= ShortWidth &&
14548 NumPositiveBits < ShortWidth) {
14549 BestType = Context.ShortTy;
14550 BestWidth = ShortWidth;
14551 } else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) {
14552 BestType = Context.IntTy;
14553 BestWidth = IntWidth;
14555 BestWidth = Context.getTargetInfo().getLongWidth();
14557 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) {
14558 BestType = Context.LongTy;
14560 BestWidth = Context.getTargetInfo().getLongLongWidth();
14562 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth)
14563 Diag(Enum->getLocation(), diag::ext_enum_too_large);
14564 BestType = Context.LongLongTy;
14567 BestPromotionType = (BestWidth <= IntWidth ? Context.IntTy : BestType);
14569 // If there is no negative value, figure out the smallest type that fits
14570 // all of the enumerator values.
14571 // If it's packed, check also if it fits a char or a short.
14572 if (Packed && NumPositiveBits <= CharWidth) {
14573 BestType = Context.UnsignedCharTy;
14574 BestPromotionType = Context.IntTy;
14575 BestWidth = CharWidth;
14576 } else if (Packed && NumPositiveBits <= ShortWidth) {
14577 BestType = Context.UnsignedShortTy;
14578 BestPromotionType = Context.IntTy;
14579 BestWidth = ShortWidth;
14580 } else if (NumPositiveBits <= IntWidth) {
14581 BestType = Context.UnsignedIntTy;
14582 BestWidth = IntWidth;
14584 = (NumPositiveBits == BestWidth || !getLangOpts().CPlusPlus)
14585 ? Context.UnsignedIntTy : Context.IntTy;
14586 } else if (NumPositiveBits <=
14587 (BestWidth = Context.getTargetInfo().getLongWidth())) {
14588 BestType = Context.UnsignedLongTy;
14590 = (NumPositiveBits == BestWidth || !getLangOpts().CPlusPlus)
14591 ? Context.UnsignedLongTy : Context.LongTy;
14593 BestWidth = Context.getTargetInfo().getLongLongWidth();
14594 assert(NumPositiveBits <= BestWidth &&
14595 "How could an initializer get larger than ULL?");
14596 BestType = Context.UnsignedLongLongTy;
14598 = (NumPositiveBits == BestWidth || !getLangOpts().CPlusPlus)
14599 ? Context.UnsignedLongLongTy : Context.LongLongTy;
14603 // Loop over all of the enumerator constants, changing their types to match
14604 // the type of the enum if needed.
14605 for (auto *D : Elements) {
14606 auto *ECD = cast_or_null<EnumConstantDecl>(D);
14607 if (!ECD) continue; // Already issued a diagnostic.
14609 // Standard C says the enumerators have int type, but we allow, as an
14610 // extension, the enumerators to be larger than int size. If each
14611 // enumerator value fits in an int, type it as an int, otherwise type it the
14612 // same as the enumerator decl itself. This means that in "enum { X = 1U }"
14613 // that X has type 'int', not 'unsigned'.
14615 // Determine whether the value fits into an int.
14616 llvm::APSInt InitVal = ECD->getInitVal();
14618 // If it fits into an integer type, force it. Otherwise force it to match
14619 // the enum decl type.
14623 if (!getLangOpts().CPlusPlus &&
14624 !Enum->isFixed() &&
14625 isRepresentableIntegerValue(Context, InitVal, Context.IntTy)) {
14626 NewTy = Context.IntTy;
14627 NewWidth = IntWidth;
14629 } else if (ECD->getType() == BestType) {
14630 // Already the right type!
14631 if (getLangOpts().CPlusPlus)
14632 // C++ [dcl.enum]p4: Following the closing brace of an
14633 // enum-specifier, each enumerator has the type of its
14635 ECD->setType(EnumType);
14639 NewWidth = BestWidth;
14640 NewSign = BestType->isSignedIntegerOrEnumerationType();
14643 // Adjust the APSInt value.
14644 InitVal = InitVal.extOrTrunc(NewWidth);
14645 InitVal.setIsSigned(NewSign);
14646 ECD->setInitVal(InitVal);
14648 // Adjust the Expr initializer and type.
14649 if (ECD->getInitExpr() &&
14650 !Context.hasSameType(NewTy, ECD->getInitExpr()->getType()))
14651 ECD->setInitExpr(ImplicitCastExpr::Create(Context, NewTy,
14653 ECD->getInitExpr(),
14654 /*base paths*/ nullptr,
14656 if (getLangOpts().CPlusPlus)
14657 // C++ [dcl.enum]p4: Following the closing brace of an
14658 // enum-specifier, each enumerator has the type of its
14660 ECD->setType(EnumType);
14662 ECD->setType(NewTy);
14665 Enum->completeDefinition(BestType, BestPromotionType,
14666 NumPositiveBits, NumNegativeBits);
14668 CheckForDuplicateEnumValues(*this, Elements, Enum, EnumType);
14670 if (Enum->hasAttr<FlagEnumAttr>()) {
14671 for (Decl *D : Elements) {
14672 EnumConstantDecl *ECD = cast_or_null<EnumConstantDecl>(D);
14673 if (!ECD) continue; // Already issued a diagnostic.
14675 llvm::APSInt InitVal = ECD->getInitVal();
14676 if (InitVal != 0 && !InitVal.isPowerOf2() &&
14677 !IsValueInFlagEnum(Enum, InitVal, true))
14678 Diag(ECD->getLocation(), diag::warn_flag_enum_constant_out_of_range)
14683 // Now that the enum type is defined, ensure it's not been underaligned.
14684 if (Enum->hasAttrs())
14685 CheckAlignasUnderalignment(Enum);
14688 Decl *Sema::ActOnFileScopeAsmDecl(Expr *expr,
14689 SourceLocation StartLoc,
14690 SourceLocation EndLoc) {
14691 StringLiteral *AsmString = cast<StringLiteral>(expr);
14693 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext,
14694 AsmString, StartLoc,
14696 CurContext->addDecl(New);
14700 static void checkModuleImportContext(Sema &S, Module *M,
14701 SourceLocation ImportLoc, DeclContext *DC,
14702 bool FromInclude = false) {
14703 SourceLocation ExternCLoc;
14705 if (auto *LSD = dyn_cast<LinkageSpecDecl>(DC)) {
14706 switch (LSD->getLanguage()) {
14707 case LinkageSpecDecl::lang_c:
14708 if (ExternCLoc.isInvalid())
14709 ExternCLoc = LSD->getLocStart();
14711 case LinkageSpecDecl::lang_cxx:
14714 DC = LSD->getParent();
14717 while (isa<LinkageSpecDecl>(DC))
14718 DC = DC->getParent();
14720 if (!isa<TranslationUnitDecl>(DC)) {
14721 S.Diag(ImportLoc, (FromInclude && S.isModuleVisible(M))
14722 ? diag::ext_module_import_not_at_top_level_noop
14723 : diag::err_module_import_not_at_top_level_fatal)
14724 << M->getFullModuleName() << DC;
14725 S.Diag(cast<Decl>(DC)->getLocStart(),
14726 diag::note_module_import_not_at_top_level) << DC;
14727 } else if (!M->IsExternC && ExternCLoc.isValid()) {
14728 S.Diag(ImportLoc, diag::ext_module_import_in_extern_c)
14729 << M->getFullModuleName();
14730 S.Diag(ExternCLoc, diag::note_module_import_in_extern_c);
14734 void Sema::diagnoseMisplacedModuleImport(Module *M, SourceLocation ImportLoc) {
14735 return checkModuleImportContext(*this, M, ImportLoc, CurContext);
14738 DeclResult Sema::ActOnModuleImport(SourceLocation AtLoc,
14739 SourceLocation ImportLoc,
14740 ModuleIdPath Path) {
14742 getModuleLoader().loadModule(ImportLoc, Path, Module::AllVisible,
14743 /*IsIncludeDirective=*/false);
14747 VisibleModules.setVisible(Mod, ImportLoc);
14749 checkModuleImportContext(*this, Mod, ImportLoc, CurContext);
14751 // FIXME: we should support importing a submodule within a different submodule
14752 // of the same top-level module. Until we do, make it an error rather than
14753 // silently ignoring the import.
14754 if (Mod->getTopLevelModuleName() == getLangOpts().CurrentModule)
14755 Diag(ImportLoc, getLangOpts().CompilingModule
14756 ? diag::err_module_self_import
14757 : diag::err_module_import_in_implementation)
14758 << Mod->getFullModuleName() << getLangOpts().CurrentModule;
14760 SmallVector<SourceLocation, 2> IdentifierLocs;
14761 Module *ModCheck = Mod;
14762 for (unsigned I = 0, N = Path.size(); I != N; ++I) {
14763 // If we've run out of module parents, just drop the remaining identifiers.
14764 // We need the length to be consistent.
14767 ModCheck = ModCheck->Parent;
14769 IdentifierLocs.push_back(Path[I].second);
14772 ImportDecl *Import = ImportDecl::Create(Context,
14773 Context.getTranslationUnitDecl(),
14774 AtLoc.isValid()? AtLoc : ImportLoc,
14775 Mod, IdentifierLocs);
14776 Context.getTranslationUnitDecl()->addDecl(Import);
14780 void Sema::ActOnModuleInclude(SourceLocation DirectiveLoc, Module *Mod) {
14781 checkModuleImportContext(*this, Mod, DirectiveLoc, CurContext, true);
14783 // Determine whether we're in the #include buffer for a module. The #includes
14784 // in that buffer do not qualify as module imports; they're just an
14785 // implementation detail of us building the module.
14787 // FIXME: Should we even get ActOnModuleInclude calls for those?
14788 bool IsInModuleIncludes =
14789 TUKind == TU_Module &&
14790 getSourceManager().isWrittenInMainFile(DirectiveLoc);
14792 // Similarly, if we're in the implementation of a module, don't
14793 // synthesize an illegal module import. FIXME: Why not?
14794 bool ShouldAddImport =
14795 !IsInModuleIncludes &&
14796 (getLangOpts().CompilingModule ||
14797 getLangOpts().CurrentModule.empty() ||
14798 getLangOpts().CurrentModule != Mod->getTopLevelModuleName());
14800 // If this module import was due to an inclusion directive, create an
14801 // implicit import declaration to capture it in the AST.
14802 if (ShouldAddImport) {
14803 TranslationUnitDecl *TU = getASTContext().getTranslationUnitDecl();
14804 ImportDecl *ImportD = ImportDecl::CreateImplicit(getASTContext(), TU,
14807 TU->addDecl(ImportD);
14808 Consumer.HandleImplicitImportDecl(ImportD);
14811 getModuleLoader().makeModuleVisible(Mod, Module::AllVisible, DirectiveLoc);
14812 VisibleModules.setVisible(Mod, DirectiveLoc);
14815 void Sema::ActOnModuleBegin(SourceLocation DirectiveLoc, Module *Mod) {
14816 checkModuleImportContext(*this, Mod, DirectiveLoc, CurContext);
14818 if (getLangOpts().ModulesLocalVisibility)
14819 VisibleModulesStack.push_back(std::move(VisibleModules));
14820 VisibleModules.setVisible(Mod, DirectiveLoc);
14823 void Sema::ActOnModuleEnd(SourceLocation DirectiveLoc, Module *Mod) {
14824 checkModuleImportContext(*this, Mod, DirectiveLoc, CurContext);
14826 if (getLangOpts().ModulesLocalVisibility) {
14827 VisibleModules = std::move(VisibleModulesStack.back());
14828 VisibleModulesStack.pop_back();
14829 VisibleModules.setVisible(Mod, DirectiveLoc);
14830 // Leaving a module hides namespace names, so our visible namespace cache
14831 // is now out of date.
14832 VisibleNamespaceCache.clear();
14836 void Sema::createImplicitModuleImportForErrorRecovery(SourceLocation Loc,
14838 // Bail if we're not allowed to implicitly import a module here.
14839 if (isSFINAEContext() || !getLangOpts().ModulesErrorRecovery)
14842 // Create the implicit import declaration.
14843 TranslationUnitDecl *TU = getASTContext().getTranslationUnitDecl();
14844 ImportDecl *ImportD = ImportDecl::CreateImplicit(getASTContext(), TU,
14846 TU->addDecl(ImportD);
14847 Consumer.HandleImplicitImportDecl(ImportD);
14849 // Make the module visible.
14850 getModuleLoader().makeModuleVisible(Mod, Module::AllVisible, Loc);
14851 VisibleModules.setVisible(Mod, Loc);
14854 void Sema::ActOnPragmaRedefineExtname(IdentifierInfo* Name,
14855 IdentifierInfo* AliasName,
14856 SourceLocation PragmaLoc,
14857 SourceLocation NameLoc,
14858 SourceLocation AliasNameLoc) {
14859 NamedDecl *PrevDecl = LookupSingleName(TUScope, Name, NameLoc,
14860 LookupOrdinaryName);
14861 AsmLabelAttr *Attr =
14862 AsmLabelAttr::CreateImplicit(Context, AliasName->getName(), AliasNameLoc);
14864 // If a declaration that:
14865 // 1) declares a function or a variable
14866 // 2) has external linkage
14867 // already exists, add a label attribute to it.
14868 if (PrevDecl && (isa<FunctionDecl>(PrevDecl) || isa<VarDecl>(PrevDecl))) {
14869 if (isDeclExternC(PrevDecl))
14870 PrevDecl->addAttr(Attr);
14872 Diag(PrevDecl->getLocation(), diag::warn_redefine_extname_not_applied)
14873 << /*Variable*/(isa<FunctionDecl>(PrevDecl) ? 0 : 1) << PrevDecl;
14874 // Otherwise, add a label atttibute to ExtnameUndeclaredIdentifiers.
14876 (void)ExtnameUndeclaredIdentifiers.insert(std::make_pair(Name, Attr));
14879 void Sema::ActOnPragmaWeakID(IdentifierInfo* Name,
14880 SourceLocation PragmaLoc,
14881 SourceLocation NameLoc) {
14882 Decl *PrevDecl = LookupSingleName(TUScope, Name, NameLoc, LookupOrdinaryName);
14885 PrevDecl->addAttr(WeakAttr::CreateImplicit(Context, PragmaLoc));
14887 (void)WeakUndeclaredIdentifiers.insert(
14888 std::pair<IdentifierInfo*,WeakInfo>
14889 (Name, WeakInfo((IdentifierInfo*)nullptr, NameLoc)));
14893 void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name,
14894 IdentifierInfo* AliasName,
14895 SourceLocation PragmaLoc,
14896 SourceLocation NameLoc,
14897 SourceLocation AliasNameLoc) {
14898 Decl *PrevDecl = LookupSingleName(TUScope, AliasName, AliasNameLoc,
14899 LookupOrdinaryName);
14900 WeakInfo W = WeakInfo(Name, NameLoc);
14902 if (PrevDecl && (isa<FunctionDecl>(PrevDecl) || isa<VarDecl>(PrevDecl))) {
14903 if (!PrevDecl->hasAttr<AliasAttr>())
14904 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl))
14905 DeclApplyPragmaWeak(TUScope, ND, W);
14907 (void)WeakUndeclaredIdentifiers.insert(
14908 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W));
14912 Decl *Sema::getObjCDeclContext() const {
14913 return (dyn_cast_or_null<ObjCContainerDecl>(CurContext));
14916 AvailabilityResult Sema::getCurContextAvailability() const {
14917 const Decl *D = cast_or_null<Decl>(getCurObjCLexicalContext());
14919 return AR_Available;
14921 // If we are within an Objective-C method, we should consult
14922 // both the availability of the method as well as the
14923 // enclosing class. If the class is (say) deprecated,
14924 // the entire method is considered deprecated from the
14925 // purpose of checking if the current context is deprecated.
14926 if (const ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) {
14927 AvailabilityResult R = MD->getAvailability();
14928 if (R != AR_Available)
14930 D = MD->getClassInterface();
14932 // If we are within an Objective-c @implementation, it
14933 // gets the same availability context as the @interface.
14934 else if (const ObjCImplementationDecl *ID =
14935 dyn_cast<ObjCImplementationDecl>(D)) {
14936 D = ID->getClassInterface();
14938 // Recover from user error.
14939 return D ? D->getAvailability() : AR_Available;