1 //===------- SemaTemplate.cpp - Semantic Analysis for C++ Templates -------===/
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //===----------------------------------------------------------------------===/
9 // This file implements semantic analysis for C++ templates.
10 //===----------------------------------------------------------------------===/
12 #include "TreeTransform.h"
13 #include "clang/AST/ASTConsumer.h"
14 #include "clang/AST/ASTContext.h"
15 #include "clang/AST/DeclFriend.h"
16 #include "clang/AST/DeclTemplate.h"
17 #include "clang/AST/Expr.h"
18 #include "clang/AST/ExprCXX.h"
19 #include "clang/AST/RecursiveASTVisitor.h"
20 #include "clang/AST/TypeVisitor.h"
21 #include "clang/Basic/LangOptions.h"
22 #include "clang/Basic/PartialDiagnostic.h"
23 #include "clang/Basic/TargetInfo.h"
24 #include "clang/Sema/DeclSpec.h"
25 #include "clang/Sema/Lookup.h"
26 #include "clang/Sema/ParsedTemplate.h"
27 #include "clang/Sema/Scope.h"
28 #include "clang/Sema/SemaInternal.h"
29 #include "clang/Sema/Template.h"
30 #include "clang/Sema/TemplateDeduction.h"
31 #include "llvm/ADT/SmallBitVector.h"
32 #include "llvm/ADT/SmallString.h"
33 #include "llvm/ADT/StringExtras.h"
34 using namespace clang;
37 // Exported for use by Parser.
39 clang::getTemplateParamsRange(TemplateParameterList const * const *Ps,
41 if (!N) return SourceRange();
42 return SourceRange(Ps[0]->getTemplateLoc(), Ps[N-1]->getRAngleLoc());
45 /// \brief Determine whether the declaration found is acceptable as the name
46 /// of a template and, if so, return that template declaration. Otherwise,
48 static NamedDecl *isAcceptableTemplateName(ASTContext &Context,
50 bool AllowFunctionTemplates) {
51 NamedDecl *D = Orig->getUnderlyingDecl();
53 if (isa<TemplateDecl>(D)) {
54 if (!AllowFunctionTemplates && isa<FunctionTemplateDecl>(D))
60 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(D)) {
61 // C++ [temp.local]p1:
62 // Like normal (non-template) classes, class templates have an
63 // injected-class-name (Clause 9). The injected-class-name
64 // can be used with or without a template-argument-list. When
65 // it is used without a template-argument-list, it is
66 // equivalent to the injected-class-name followed by the
67 // template-parameters of the class template enclosed in
68 // <>. When it is used with a template-argument-list, it
69 // refers to the specified class template specialization,
70 // which could be the current specialization or another
72 if (Record->isInjectedClassName()) {
73 Record = cast<CXXRecordDecl>(Record->getDeclContext());
74 if (Record->getDescribedClassTemplate())
75 return Record->getDescribedClassTemplate();
77 if (ClassTemplateSpecializationDecl *Spec
78 = dyn_cast<ClassTemplateSpecializationDecl>(Record))
79 return Spec->getSpecializedTemplate();
88 void Sema::FilterAcceptableTemplateNames(LookupResult &R,
89 bool AllowFunctionTemplates) {
90 // The set of class templates we've already seen.
91 llvm::SmallPtrSet<ClassTemplateDecl *, 8> ClassTemplates;
92 LookupResult::Filter filter = R.makeFilter();
93 while (filter.hasNext()) {
94 NamedDecl *Orig = filter.next();
95 NamedDecl *Repl = isAcceptableTemplateName(Context, Orig,
96 AllowFunctionTemplates);
99 else if (Repl != Orig) {
101 // C++ [temp.local]p3:
102 // A lookup that finds an injected-class-name (10.2) can result in an
103 // ambiguity in certain cases (for example, if it is found in more than
104 // one base class). If all of the injected-class-names that are found
105 // refer to specializations of the same class template, and if the name
106 // is used as a template-name, the reference refers to the class
107 // template itself and not a specialization thereof, and is not
109 if (ClassTemplateDecl *ClassTmpl = dyn_cast<ClassTemplateDecl>(Repl))
110 if (!ClassTemplates.insert(ClassTmpl).second) {
115 // FIXME: we promote access to public here as a workaround to
116 // the fact that LookupResult doesn't let us remember that we
117 // found this template through a particular injected class name,
118 // which means we end up doing nasty things to the invariants.
119 // Pretending that access is public is *much* safer.
120 filter.replace(Repl, AS_public);
126 bool Sema::hasAnyAcceptableTemplateNames(LookupResult &R,
127 bool AllowFunctionTemplates) {
128 for (LookupResult::iterator I = R.begin(), IEnd = R.end(); I != IEnd; ++I)
129 if (isAcceptableTemplateName(Context, *I, AllowFunctionTemplates))
135 TemplateNameKind Sema::isTemplateName(Scope *S,
137 bool hasTemplateKeyword,
139 ParsedType ObjectTypePtr,
140 bool EnteringContext,
141 TemplateTy &TemplateResult,
142 bool &MemberOfUnknownSpecialization) {
143 assert(getLangOpts().CPlusPlus && "No template names in C!");
145 DeclarationName TName;
146 MemberOfUnknownSpecialization = false;
148 switch (Name.getKind()) {
149 case UnqualifiedId::IK_Identifier:
150 TName = DeclarationName(Name.Identifier);
153 case UnqualifiedId::IK_OperatorFunctionId:
154 TName = Context.DeclarationNames.getCXXOperatorName(
155 Name.OperatorFunctionId.Operator);
158 case UnqualifiedId::IK_LiteralOperatorId:
159 TName = Context.DeclarationNames.getCXXLiteralOperatorName(Name.Identifier);
163 return TNK_Non_template;
166 QualType ObjectType = ObjectTypePtr.get();
168 LookupResult R(*this, TName, Name.getLocStart(), LookupOrdinaryName);
169 LookupTemplateName(R, S, SS, ObjectType, EnteringContext,
170 MemberOfUnknownSpecialization);
171 if (R.empty()) return TNK_Non_template;
172 if (R.isAmbiguous()) {
173 // Suppress diagnostics; we'll redo this lookup later.
174 R.suppressDiagnostics();
176 // FIXME: we might have ambiguous templates, in which case we
177 // should at least parse them properly!
178 return TNK_Non_template;
181 TemplateName Template;
182 TemplateNameKind TemplateKind;
184 unsigned ResultCount = R.end() - R.begin();
185 if (ResultCount > 1) {
186 // We assume that we'll preserve the qualifier from a function
187 // template name in other ways.
188 Template = Context.getOverloadedTemplateName(R.begin(), R.end());
189 TemplateKind = TNK_Function_template;
191 // We'll do this lookup again later.
192 R.suppressDiagnostics();
194 TemplateDecl *TD = cast<TemplateDecl>((*R.begin())->getUnderlyingDecl());
196 if (SS.isSet() && !SS.isInvalid()) {
197 NestedNameSpecifier *Qualifier = SS.getScopeRep();
198 Template = Context.getQualifiedTemplateName(Qualifier,
199 hasTemplateKeyword, TD);
201 Template = TemplateName(TD);
204 if (isa<FunctionTemplateDecl>(TD)) {
205 TemplateKind = TNK_Function_template;
207 // We'll do this lookup again later.
208 R.suppressDiagnostics();
210 assert(isa<ClassTemplateDecl>(TD) || isa<TemplateTemplateParmDecl>(TD) ||
211 isa<TypeAliasTemplateDecl>(TD) || isa<VarTemplateDecl>(TD));
213 isa<VarTemplateDecl>(TD) ? TNK_Var_template : TNK_Type_template;
217 TemplateResult = TemplateTy::make(Template);
221 bool Sema::DiagnoseUnknownTemplateName(const IdentifierInfo &II,
222 SourceLocation IILoc,
224 const CXXScopeSpec *SS,
225 TemplateTy &SuggestedTemplate,
226 TemplateNameKind &SuggestedKind) {
227 // We can't recover unless there's a dependent scope specifier preceding the
229 // FIXME: Typo correction?
230 if (!SS || !SS->isSet() || !isDependentScopeSpecifier(*SS) ||
231 computeDeclContext(*SS))
234 // The code is missing a 'template' keyword prior to the dependent template
236 NestedNameSpecifier *Qualifier = (NestedNameSpecifier*)SS->getScopeRep();
237 Diag(IILoc, diag::err_template_kw_missing)
238 << Qualifier << II.getName()
239 << FixItHint::CreateInsertion(IILoc, "template ");
241 = TemplateTy::make(Context.getDependentTemplateName(Qualifier, &II));
242 SuggestedKind = TNK_Dependent_template_name;
246 void Sema::LookupTemplateName(LookupResult &Found,
247 Scope *S, CXXScopeSpec &SS,
249 bool EnteringContext,
250 bool &MemberOfUnknownSpecialization) {
251 // Determine where to perform name lookup
252 MemberOfUnknownSpecialization = false;
253 DeclContext *LookupCtx = nullptr;
254 bool isDependent = false;
255 if (!ObjectType.isNull()) {
256 // This nested-name-specifier occurs in a member access expression, e.g.,
257 // x->B::f, and we are looking into the type of the object.
258 assert(!SS.isSet() && "ObjectType and scope specifier cannot coexist");
259 LookupCtx = computeDeclContext(ObjectType);
260 isDependent = ObjectType->isDependentType();
261 assert((isDependent || !ObjectType->isIncompleteType() ||
262 ObjectType->castAs<TagType>()->isBeingDefined()) &&
263 "Caller should have completed object type");
265 // Template names cannot appear inside an Objective-C class or object type.
266 if (ObjectType->isObjCObjectOrInterfaceType()) {
270 } else if (SS.isSet()) {
271 // This nested-name-specifier occurs after another nested-name-specifier,
272 // so long into the context associated with the prior nested-name-specifier.
273 LookupCtx = computeDeclContext(SS, EnteringContext);
274 isDependent = isDependentScopeSpecifier(SS);
276 // The declaration context must be complete.
277 if (LookupCtx && RequireCompleteDeclContext(SS, LookupCtx))
281 bool ObjectTypeSearchedInScope = false;
282 bool AllowFunctionTemplatesInLookup = true;
284 // Perform "qualified" name lookup into the declaration context we
285 // computed, which is either the type of the base of a member access
286 // expression or the declaration context associated with a prior
287 // nested-name-specifier.
288 LookupQualifiedName(Found, LookupCtx);
289 if (!ObjectType.isNull() && Found.empty()) {
290 // C++ [basic.lookup.classref]p1:
291 // In a class member access expression (5.2.5), if the . or -> token is
292 // immediately followed by an identifier followed by a <, the
293 // identifier must be looked up to determine whether the < is the
294 // beginning of a template argument list (14.2) or a less-than operator.
295 // The identifier is first looked up in the class of the object
296 // expression. If the identifier is not found, it is then looked up in
297 // the context of the entire postfix-expression and shall name a class
298 // or function template.
299 if (S) LookupName(Found, S);
300 ObjectTypeSearchedInScope = true;
301 AllowFunctionTemplatesInLookup = false;
303 } else if (isDependent && (!S || ObjectType.isNull())) {
304 // We cannot look into a dependent object type or nested nme
306 MemberOfUnknownSpecialization = true;
309 // Perform unqualified name lookup in the current scope.
310 LookupName(Found, S);
312 if (!ObjectType.isNull())
313 AllowFunctionTemplatesInLookup = false;
316 if (Found.empty() && !isDependent) {
317 // If we did not find any names, attempt to correct any typos.
318 DeclarationName Name = Found.getLookupName();
320 // Simple filter callback that, for keywords, only accepts the C++ *_cast
321 auto FilterCCC = llvm::make_unique<CorrectionCandidateCallback>();
322 FilterCCC->WantTypeSpecifiers = false;
323 FilterCCC->WantExpressionKeywords = false;
324 FilterCCC->WantRemainingKeywords = false;
325 FilterCCC->WantCXXNamedCasts = true;
326 if (TypoCorrection Corrected = CorrectTypo(
327 Found.getLookupNameInfo(), Found.getLookupKind(), S, &SS,
328 std::move(FilterCCC), CTK_ErrorRecovery, LookupCtx)) {
329 Found.setLookupName(Corrected.getCorrection());
330 if (Corrected.getCorrectionDecl())
331 Found.addDecl(Corrected.getCorrectionDecl());
332 FilterAcceptableTemplateNames(Found);
333 if (!Found.empty()) {
335 std::string CorrectedStr(Corrected.getAsString(getLangOpts()));
336 bool DroppedSpecifier = Corrected.WillReplaceSpecifier() &&
337 Name.getAsString() == CorrectedStr;
338 diagnoseTypo(Corrected, PDiag(diag::err_no_member_template_suggest)
339 << Name << LookupCtx << DroppedSpecifier
342 diagnoseTypo(Corrected, PDiag(diag::err_no_template_suggest) << Name);
346 Found.setLookupName(Name);
350 FilterAcceptableTemplateNames(Found, AllowFunctionTemplatesInLookup);
353 MemberOfUnknownSpecialization = true;
357 if (S && !ObjectType.isNull() && !ObjectTypeSearchedInScope &&
358 !getLangOpts().CPlusPlus11) {
359 // C++03 [basic.lookup.classref]p1:
360 // [...] If the lookup in the class of the object expression finds a
361 // template, the name is also looked up in the context of the entire
362 // postfix-expression and [...]
364 // Note: C++11 does not perform this second lookup.
365 LookupResult FoundOuter(*this, Found.getLookupName(), Found.getNameLoc(),
367 LookupName(FoundOuter, S);
368 FilterAcceptableTemplateNames(FoundOuter, /*AllowFunctionTemplates=*/false);
370 if (FoundOuter.empty()) {
371 // - if the name is not found, the name found in the class of the
372 // object expression is used, otherwise
373 } else if (!FoundOuter.getAsSingle<ClassTemplateDecl>() ||
374 FoundOuter.isAmbiguous()) {
375 // - if the name is found in the context of the entire
376 // postfix-expression and does not name a class template, the name
377 // found in the class of the object expression is used, otherwise
379 } else if (!Found.isSuppressingDiagnostics()) {
380 // - if the name found is a class template, it must refer to the same
381 // entity as the one found in the class of the object expression,
382 // otherwise the program is ill-formed.
383 if (!Found.isSingleResult() ||
384 Found.getFoundDecl()->getCanonicalDecl()
385 != FoundOuter.getFoundDecl()->getCanonicalDecl()) {
386 Diag(Found.getNameLoc(),
387 diag::ext_nested_name_member_ref_lookup_ambiguous)
388 << Found.getLookupName()
390 Diag(Found.getRepresentativeDecl()->getLocation(),
391 diag::note_ambig_member_ref_object_type)
393 Diag(FoundOuter.getFoundDecl()->getLocation(),
394 diag::note_ambig_member_ref_scope);
396 // Recover by taking the template that we found in the object
397 // expression's type.
403 /// ActOnDependentIdExpression - Handle a dependent id-expression that
404 /// was just parsed. This is only possible with an explicit scope
405 /// specifier naming a dependent type.
407 Sema::ActOnDependentIdExpression(const CXXScopeSpec &SS,
408 SourceLocation TemplateKWLoc,
409 const DeclarationNameInfo &NameInfo,
410 bool isAddressOfOperand,
411 const TemplateArgumentListInfo *TemplateArgs) {
412 DeclContext *DC = getFunctionLevelDeclContext();
414 if (!isAddressOfOperand &&
415 isa<CXXMethodDecl>(DC) &&
416 cast<CXXMethodDecl>(DC)->isInstance()) {
417 QualType ThisType = cast<CXXMethodDecl>(DC)->getThisType(Context);
419 // Since the 'this' expression is synthesized, we don't need to
420 // perform the double-lookup check.
421 NamedDecl *FirstQualifierInScope = nullptr;
423 return CXXDependentScopeMemberExpr::Create(
424 Context, /*This*/ nullptr, ThisType, /*IsArrow*/ true,
425 /*Op*/ SourceLocation(), SS.getWithLocInContext(Context), TemplateKWLoc,
426 FirstQualifierInScope, NameInfo, TemplateArgs);
429 return BuildDependentDeclRefExpr(SS, TemplateKWLoc, NameInfo, TemplateArgs);
433 Sema::BuildDependentDeclRefExpr(const CXXScopeSpec &SS,
434 SourceLocation TemplateKWLoc,
435 const DeclarationNameInfo &NameInfo,
436 const TemplateArgumentListInfo *TemplateArgs) {
437 return DependentScopeDeclRefExpr::Create(
438 Context, SS.getWithLocInContext(Context), TemplateKWLoc, NameInfo,
442 /// DiagnoseTemplateParameterShadow - Produce a diagnostic complaining
443 /// that the template parameter 'PrevDecl' is being shadowed by a new
444 /// declaration at location Loc. Returns true to indicate that this is
445 /// an error, and false otherwise.
446 void Sema::DiagnoseTemplateParameterShadow(SourceLocation Loc, Decl *PrevDecl) {
447 assert(PrevDecl->isTemplateParameter() && "Not a template parameter");
449 // Microsoft Visual C++ permits template parameters to be shadowed.
450 if (getLangOpts().MicrosoftExt)
453 // C++ [temp.local]p4:
454 // A template-parameter shall not be redeclared within its
455 // scope (including nested scopes).
456 Diag(Loc, diag::err_template_param_shadow)
457 << cast<NamedDecl>(PrevDecl)->getDeclName();
458 Diag(PrevDecl->getLocation(), diag::note_template_param_here);
462 /// AdjustDeclIfTemplate - If the given decl happens to be a template, reset
463 /// the parameter D to reference the templated declaration and return a pointer
464 /// to the template declaration. Otherwise, do nothing to D and return null.
465 TemplateDecl *Sema::AdjustDeclIfTemplate(Decl *&D) {
466 if (TemplateDecl *Temp = dyn_cast_or_null<TemplateDecl>(D)) {
467 D = Temp->getTemplatedDecl();
473 ParsedTemplateArgument ParsedTemplateArgument::getTemplatePackExpansion(
474 SourceLocation EllipsisLoc) const {
475 assert(Kind == Template &&
476 "Only template template arguments can be pack expansions here");
477 assert(getAsTemplate().get().containsUnexpandedParameterPack() &&
478 "Template template argument pack expansion without packs");
479 ParsedTemplateArgument Result(*this);
480 Result.EllipsisLoc = EllipsisLoc;
484 static TemplateArgumentLoc translateTemplateArgument(Sema &SemaRef,
485 const ParsedTemplateArgument &Arg) {
487 switch (Arg.getKind()) {
488 case ParsedTemplateArgument::Type: {
490 QualType T = SemaRef.GetTypeFromParser(Arg.getAsType(), &DI);
492 DI = SemaRef.Context.getTrivialTypeSourceInfo(T, Arg.getLocation());
493 return TemplateArgumentLoc(TemplateArgument(T), DI);
496 case ParsedTemplateArgument::NonType: {
497 Expr *E = static_cast<Expr *>(Arg.getAsExpr());
498 return TemplateArgumentLoc(TemplateArgument(E), E);
501 case ParsedTemplateArgument::Template: {
502 TemplateName Template = Arg.getAsTemplate().get();
503 TemplateArgument TArg;
504 if (Arg.getEllipsisLoc().isValid())
505 TArg = TemplateArgument(Template, Optional<unsigned int>());
508 return TemplateArgumentLoc(TArg,
509 Arg.getScopeSpec().getWithLocInContext(
512 Arg.getEllipsisLoc());
516 llvm_unreachable("Unhandled parsed template argument");
519 /// \brief Translates template arguments as provided by the parser
520 /// into template arguments used by semantic analysis.
521 void Sema::translateTemplateArguments(const ASTTemplateArgsPtr &TemplateArgsIn,
522 TemplateArgumentListInfo &TemplateArgs) {
523 for (unsigned I = 0, Last = TemplateArgsIn.size(); I != Last; ++I)
524 TemplateArgs.addArgument(translateTemplateArgument(*this,
528 static void maybeDiagnoseTemplateParameterShadow(Sema &SemaRef, Scope *S,
530 IdentifierInfo *Name) {
531 NamedDecl *PrevDecl = SemaRef.LookupSingleName(
532 S, Name, Loc, Sema::LookupOrdinaryName, Sema::ForRedeclaration);
533 if (PrevDecl && PrevDecl->isTemplateParameter())
534 SemaRef.DiagnoseTemplateParameterShadow(Loc, PrevDecl);
537 /// ActOnTypeParameter - Called when a C++ template type parameter
538 /// (e.g., "typename T") has been parsed. Typename specifies whether
539 /// the keyword "typename" was used to declare the type parameter
540 /// (otherwise, "class" was used), and KeyLoc is the location of the
541 /// "class" or "typename" keyword. ParamName is the name of the
542 /// parameter (NULL indicates an unnamed template parameter) and
543 /// ParamNameLoc is the location of the parameter name (if any).
544 /// If the type parameter has a default argument, it will be added
545 /// later via ActOnTypeParameterDefault.
546 Decl *Sema::ActOnTypeParameter(Scope *S, bool Typename,
547 SourceLocation EllipsisLoc,
548 SourceLocation KeyLoc,
549 IdentifierInfo *ParamName,
550 SourceLocation ParamNameLoc,
551 unsigned Depth, unsigned Position,
552 SourceLocation EqualLoc,
553 ParsedType DefaultArg) {
554 assert(S->isTemplateParamScope() &&
555 "Template type parameter not in template parameter scope!");
556 bool Invalid = false;
558 SourceLocation Loc = ParamNameLoc;
562 bool IsParameterPack = EllipsisLoc.isValid();
563 TemplateTypeParmDecl *Param
564 = TemplateTypeParmDecl::Create(Context, Context.getTranslationUnitDecl(),
565 KeyLoc, Loc, Depth, Position, ParamName,
566 Typename, IsParameterPack);
567 Param->setAccess(AS_public);
569 Param->setInvalidDecl();
572 maybeDiagnoseTemplateParameterShadow(*this, S, ParamNameLoc, ParamName);
574 // Add the template parameter into the current scope.
576 IdResolver.AddDecl(Param);
579 // C++0x [temp.param]p9:
580 // A default template-argument may be specified for any kind of
581 // template-parameter that is not a template parameter pack.
582 if (DefaultArg && IsParameterPack) {
583 Diag(EqualLoc, diag::err_template_param_pack_default_arg);
584 DefaultArg = ParsedType();
587 // Handle the default argument, if provided.
589 TypeSourceInfo *DefaultTInfo;
590 GetTypeFromParser(DefaultArg, &DefaultTInfo);
592 assert(DefaultTInfo && "expected source information for type");
594 // Check for unexpanded parameter packs.
595 if (DiagnoseUnexpandedParameterPack(Loc, DefaultTInfo,
596 UPPC_DefaultArgument))
599 // Check the template argument itself.
600 if (CheckTemplateArgument(Param, DefaultTInfo)) {
601 Param->setInvalidDecl();
605 Param->setDefaultArgument(DefaultTInfo, false);
611 /// \brief Check that the type of a non-type template parameter is
614 /// \returns the (possibly-promoted) parameter type if valid;
615 /// otherwise, produces a diagnostic and returns a NULL type.
617 Sema::CheckNonTypeTemplateParameterType(QualType T, SourceLocation Loc) {
618 // We don't allow variably-modified types as the type of non-type template
620 if (T->isVariablyModifiedType()) {
621 Diag(Loc, diag::err_variably_modified_nontype_template_param)
626 // C++ [temp.param]p4:
628 // A non-type template-parameter shall have one of the following
629 // (optionally cv-qualified) types:
631 // -- integral or enumeration type,
632 if (T->isIntegralOrEnumerationType() ||
633 // -- pointer to object or pointer to function,
634 T->isPointerType() ||
635 // -- reference to object or reference to function,
636 T->isReferenceType() ||
637 // -- pointer to member,
638 T->isMemberPointerType() ||
639 // -- std::nullptr_t.
640 T->isNullPtrType() ||
641 // If T is a dependent type, we can't do the check now, so we
642 // assume that it is well-formed.
643 T->isDependentType()) {
644 // C++ [temp.param]p5: The top-level cv-qualifiers on the template-parameter
645 // are ignored when determining its type.
646 return T.getUnqualifiedType();
649 // C++ [temp.param]p8:
651 // A non-type template-parameter of type "array of T" or
652 // "function returning T" is adjusted to be of type "pointer to
653 // T" or "pointer to function returning T", respectively.
654 else if (T->isArrayType())
655 // FIXME: Keep the type prior to promotion?
656 return Context.getArrayDecayedType(T);
657 else if (T->isFunctionType())
658 // FIXME: Keep the type prior to promotion?
659 return Context.getPointerType(T);
661 Diag(Loc, diag::err_template_nontype_parm_bad_type)
667 Decl *Sema::ActOnNonTypeTemplateParameter(Scope *S, Declarator &D,
670 SourceLocation EqualLoc,
672 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S);
673 QualType T = TInfo->getType();
675 assert(S->isTemplateParamScope() &&
676 "Non-type template parameter not in template parameter scope!");
677 bool Invalid = false;
679 T = CheckNonTypeTemplateParameterType(T, D.getIdentifierLoc());
681 T = Context.IntTy; // Recover with an 'int' type.
685 IdentifierInfo *ParamName = D.getIdentifier();
686 bool IsParameterPack = D.hasEllipsis();
687 NonTypeTemplateParmDecl *Param
688 = NonTypeTemplateParmDecl::Create(Context, Context.getTranslationUnitDecl(),
690 D.getIdentifierLoc(),
691 Depth, Position, ParamName, T,
692 IsParameterPack, TInfo);
693 Param->setAccess(AS_public);
696 Param->setInvalidDecl();
699 maybeDiagnoseTemplateParameterShadow(*this, S, D.getIdentifierLoc(),
702 // Add the template parameter into the current scope.
704 IdResolver.AddDecl(Param);
707 // C++0x [temp.param]p9:
708 // A default template-argument may be specified for any kind of
709 // template-parameter that is not a template parameter pack.
710 if (Default && IsParameterPack) {
711 Diag(EqualLoc, diag::err_template_param_pack_default_arg);
715 // Check the well-formedness of the default template argument, if provided.
717 // Check for unexpanded parameter packs.
718 if (DiagnoseUnexpandedParameterPack(Default, UPPC_DefaultArgument))
721 TemplateArgument Converted;
722 ExprResult DefaultRes = CheckTemplateArgument(Param, Param->getType(), Default, Converted);
723 if (DefaultRes.isInvalid()) {
724 Param->setInvalidDecl();
727 Default = DefaultRes.get();
729 Param->setDefaultArgument(Default, false);
735 /// ActOnTemplateTemplateParameter - Called when a C++ template template
736 /// parameter (e.g. T in template <template \<typename> class T> class array)
737 /// has been parsed. S is the current scope.
738 Decl *Sema::ActOnTemplateTemplateParameter(Scope* S,
739 SourceLocation TmpLoc,
740 TemplateParameterList *Params,
741 SourceLocation EllipsisLoc,
742 IdentifierInfo *Name,
743 SourceLocation NameLoc,
746 SourceLocation EqualLoc,
747 ParsedTemplateArgument Default) {
748 assert(S->isTemplateParamScope() &&
749 "Template template parameter not in template parameter scope!");
751 // Construct the parameter object.
752 bool IsParameterPack = EllipsisLoc.isValid();
753 TemplateTemplateParmDecl *Param =
754 TemplateTemplateParmDecl::Create(Context, Context.getTranslationUnitDecl(),
755 NameLoc.isInvalid()? TmpLoc : NameLoc,
756 Depth, Position, IsParameterPack,
758 Param->setAccess(AS_public);
760 // If the template template parameter has a name, then link the identifier
761 // into the scope and lookup mechanisms.
763 maybeDiagnoseTemplateParameterShadow(*this, S, NameLoc, Name);
766 IdResolver.AddDecl(Param);
769 if (Params->size() == 0) {
770 Diag(Param->getLocation(), diag::err_template_template_parm_no_parms)
771 << SourceRange(Params->getLAngleLoc(), Params->getRAngleLoc());
772 Param->setInvalidDecl();
775 // C++0x [temp.param]p9:
776 // A default template-argument may be specified for any kind of
777 // template-parameter that is not a template parameter pack.
778 if (IsParameterPack && !Default.isInvalid()) {
779 Diag(EqualLoc, diag::err_template_param_pack_default_arg);
780 Default = ParsedTemplateArgument();
783 if (!Default.isInvalid()) {
784 // Check only that we have a template template argument. We don't want to
785 // try to check well-formedness now, because our template template parameter
786 // might have dependent types in its template parameters, which we wouldn't
787 // be able to match now.
789 // If none of the template template parameter's template arguments mention
790 // other template parameters, we could actually perform more checking here.
791 // However, it isn't worth doing.
792 TemplateArgumentLoc DefaultArg = translateTemplateArgument(*this, Default);
793 if (DefaultArg.getArgument().getAsTemplate().isNull()) {
794 Diag(DefaultArg.getLocation(), diag::err_template_arg_not_class_template)
795 << DefaultArg.getSourceRange();
799 // Check for unexpanded parameter packs.
800 if (DiagnoseUnexpandedParameterPack(DefaultArg.getLocation(),
801 DefaultArg.getArgument().getAsTemplate(),
802 UPPC_DefaultArgument))
805 Param->setDefaultArgument(DefaultArg, false);
811 /// ActOnTemplateParameterList - Builds a TemplateParameterList that
812 /// contains the template parameters in Params/NumParams.
813 TemplateParameterList *
814 Sema::ActOnTemplateParameterList(unsigned Depth,
815 SourceLocation ExportLoc,
816 SourceLocation TemplateLoc,
817 SourceLocation LAngleLoc,
818 Decl **Params, unsigned NumParams,
819 SourceLocation RAngleLoc) {
820 if (ExportLoc.isValid())
821 Diag(ExportLoc, diag::warn_template_export_unsupported);
823 return TemplateParameterList::Create(Context, TemplateLoc, LAngleLoc,
824 (NamedDecl**)Params, NumParams,
828 static void SetNestedNameSpecifier(TagDecl *T, const CXXScopeSpec &SS) {
830 T->setQualifierInfo(SS.getWithLocInContext(T->getASTContext()));
834 Sema::CheckClassTemplate(Scope *S, unsigned TagSpec, TagUseKind TUK,
835 SourceLocation KWLoc, CXXScopeSpec &SS,
836 IdentifierInfo *Name, SourceLocation NameLoc,
838 TemplateParameterList *TemplateParams,
839 AccessSpecifier AS, SourceLocation ModulePrivateLoc,
840 SourceLocation FriendLoc,
841 unsigned NumOuterTemplateParamLists,
842 TemplateParameterList** OuterTemplateParamLists) {
843 assert(TemplateParams && TemplateParams->size() > 0 &&
844 "No template parameters");
845 assert(TUK != TUK_Reference && "Can only declare or define class templates");
846 bool Invalid = false;
848 // Check that we can declare a template here.
849 if (CheckTemplateDeclScope(S, TemplateParams))
852 TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec);
853 assert(Kind != TTK_Enum && "can't build template of enumerated type");
855 // There is no such thing as an unnamed class template.
857 Diag(KWLoc, diag::err_template_unnamed_class);
861 // Find any previous declaration with this name. For a friend with no
862 // scope explicitly specified, we only look for tag declarations (per
863 // C++11 [basic.lookup.elab]p2).
864 DeclContext *SemanticContext;
865 LookupResult Previous(*this, Name, NameLoc,
866 (SS.isEmpty() && TUK == TUK_Friend)
867 ? LookupTagName : LookupOrdinaryName,
869 if (SS.isNotEmpty() && !SS.isInvalid()) {
870 SemanticContext = computeDeclContext(SS, true);
871 if (!SemanticContext) {
872 // FIXME: Horrible, horrible hack! We can't currently represent this
873 // in the AST, and historically we have just ignored such friend
874 // class templates, so don't complain here.
875 Diag(NameLoc, TUK == TUK_Friend
876 ? diag::warn_template_qualified_friend_ignored
877 : diag::err_template_qualified_declarator_no_match)
878 << SS.getScopeRep() << SS.getRange();
879 return TUK != TUK_Friend;
882 if (RequireCompleteDeclContext(SS, SemanticContext))
885 // If we're adding a template to a dependent context, we may need to
886 // rebuilding some of the types used within the template parameter list,
887 // now that we know what the current instantiation is.
888 if (SemanticContext->isDependentContext()) {
889 ContextRAII SavedContext(*this, SemanticContext);
890 if (RebuildTemplateParamsInCurrentInstantiation(TemplateParams))
892 } else if (TUK != TUK_Friend && TUK != TUK_Reference)
893 diagnoseQualifiedDeclaration(SS, SemanticContext, Name, NameLoc);
895 LookupQualifiedName(Previous, SemanticContext);
897 SemanticContext = CurContext;
898 LookupName(Previous, S);
901 if (Previous.isAmbiguous())
904 NamedDecl *PrevDecl = nullptr;
905 if (Previous.begin() != Previous.end())
906 PrevDecl = (*Previous.begin())->getUnderlyingDecl();
908 // If there is a previous declaration with the same name, check
909 // whether this is a valid redeclaration.
910 ClassTemplateDecl *PrevClassTemplate
911 = dyn_cast_or_null<ClassTemplateDecl>(PrevDecl);
913 // We may have found the injected-class-name of a class template,
914 // class template partial specialization, or class template specialization.
915 // In these cases, grab the template that is being defined or specialized.
916 if (!PrevClassTemplate && PrevDecl && isa<CXXRecordDecl>(PrevDecl) &&
917 cast<CXXRecordDecl>(PrevDecl)->isInjectedClassName()) {
918 PrevDecl = cast<CXXRecordDecl>(PrevDecl->getDeclContext());
920 = cast<CXXRecordDecl>(PrevDecl)->getDescribedClassTemplate();
921 if (!PrevClassTemplate && isa<ClassTemplateSpecializationDecl>(PrevDecl)) {
923 = cast<ClassTemplateSpecializationDecl>(PrevDecl)
924 ->getSpecializedTemplate();
928 if (TUK == TUK_Friend) {
929 // C++ [namespace.memdef]p3:
930 // [...] When looking for a prior declaration of a class or a function
931 // declared as a friend, and when the name of the friend class or
932 // function is neither a qualified name nor a template-id, scopes outside
933 // the innermost enclosing namespace scope are not considered.
935 DeclContext *OutermostContext = CurContext;
936 while (!OutermostContext->isFileContext())
937 OutermostContext = OutermostContext->getLookupParent();
940 (OutermostContext->Equals(PrevDecl->getDeclContext()) ||
941 OutermostContext->Encloses(PrevDecl->getDeclContext()))) {
942 SemanticContext = PrevDecl->getDeclContext();
944 // Declarations in outer scopes don't matter. However, the outermost
945 // context we computed is the semantic context for our new
947 PrevDecl = PrevClassTemplate = nullptr;
948 SemanticContext = OutermostContext;
950 // Check that the chosen semantic context doesn't already contain a
951 // declaration of this name as a non-tag type.
952 LookupResult Previous(*this, Name, NameLoc, LookupOrdinaryName,
954 DeclContext *LookupContext = SemanticContext;
955 while (LookupContext->isTransparentContext())
956 LookupContext = LookupContext->getLookupParent();
957 LookupQualifiedName(Previous, LookupContext);
959 if (Previous.isAmbiguous())
962 if (Previous.begin() != Previous.end())
963 PrevDecl = (*Previous.begin())->getUnderlyingDecl();
966 } else if (PrevDecl &&
967 !isDeclInScope(PrevDecl, SemanticContext, S, SS.isValid()))
968 PrevDecl = PrevClassTemplate = nullptr;
970 if (PrevClassTemplate) {
971 // Ensure that the template parameter lists are compatible. Skip this check
972 // for a friend in a dependent context: the template parameter list itself
973 // could be dependent.
974 if (!(TUK == TUK_Friend && CurContext->isDependentContext()) &&
975 !TemplateParameterListsAreEqual(TemplateParams,
976 PrevClassTemplate->getTemplateParameters(),
981 // C++ [temp.class]p4:
982 // In a redeclaration, partial specialization, explicit
983 // specialization or explicit instantiation of a class template,
984 // the class-key shall agree in kind with the original class
985 // template declaration (7.1.5.3).
986 RecordDecl *PrevRecordDecl = PrevClassTemplate->getTemplatedDecl();
987 if (!isAcceptableTagRedeclaration(PrevRecordDecl, Kind,
988 TUK == TUK_Definition, KWLoc, *Name)) {
989 Diag(KWLoc, diag::err_use_with_wrong_tag)
991 << FixItHint::CreateReplacement(KWLoc, PrevRecordDecl->getKindName());
992 Diag(PrevRecordDecl->getLocation(), diag::note_previous_use);
993 Kind = PrevRecordDecl->getTagKind();
996 // Check for redefinition of this class template.
997 if (TUK == TUK_Definition) {
998 if (TagDecl *Def = PrevRecordDecl->getDefinition()) {
999 Diag(NameLoc, diag::err_redefinition) << Name;
1000 Diag(Def->getLocation(), diag::note_previous_definition);
1001 // FIXME: Would it make sense to try to "forget" the previous
1002 // definition, as part of error recovery?
1006 } else if (PrevDecl && PrevDecl->isTemplateParameter()) {
1007 // Maybe we will complain about the shadowed template parameter.
1008 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl);
1009 // Just pretend that we didn't see the previous declaration.
1011 } else if (PrevDecl) {
1013 // A class template shall not have the same name as any other
1014 // template, class, function, object, enumeration, enumerator,
1015 // namespace, or type in the same scope (3.3), except as specified
1017 Diag(NameLoc, diag::err_redefinition_different_kind) << Name;
1018 Diag(PrevDecl->getLocation(), diag::note_previous_definition);
1022 // Check the template parameter list of this declaration, possibly
1023 // merging in the template parameter list from the previous class
1024 // template declaration. Skip this check for a friend in a dependent
1025 // context, because the template parameter list might be dependent.
1026 if (!(TUK == TUK_Friend && CurContext->isDependentContext()) &&
1027 CheckTemplateParameterList(
1029 PrevClassTemplate ? PrevClassTemplate->getTemplateParameters()
1031 (SS.isSet() && SemanticContext && SemanticContext->isRecord() &&
1032 SemanticContext->isDependentContext())
1033 ? TPC_ClassTemplateMember
1034 : TUK == TUK_Friend ? TPC_FriendClassTemplate
1035 : TPC_ClassTemplate))
1039 // If the name of the template was qualified, we must be defining the
1040 // template out-of-line.
1041 if (!SS.isInvalid() && !Invalid && !PrevClassTemplate) {
1042 Diag(NameLoc, TUK == TUK_Friend ? diag::err_friend_decl_does_not_match
1043 : diag::err_member_decl_does_not_match)
1044 << Name << SemanticContext << /*IsDefinition*/true << SS.getRange();
1049 CXXRecordDecl *NewClass =
1050 CXXRecordDecl::Create(Context, Kind, SemanticContext, KWLoc, NameLoc, Name,
1052 PrevClassTemplate->getTemplatedDecl() : nullptr,
1053 /*DelayTypeCreation=*/true);
1054 SetNestedNameSpecifier(NewClass, SS);
1055 if (NumOuterTemplateParamLists > 0)
1056 NewClass->setTemplateParameterListsInfo(Context,
1057 NumOuterTemplateParamLists,
1058 OuterTemplateParamLists);
1060 // Add alignment attributes if necessary; these attributes are checked when
1061 // the ASTContext lays out the structure.
1062 if (TUK == TUK_Definition) {
1063 AddAlignmentAttributesForRecord(NewClass);
1064 AddMsStructLayoutForRecord(NewClass);
1067 ClassTemplateDecl *NewTemplate
1068 = ClassTemplateDecl::Create(Context, SemanticContext, NameLoc,
1069 DeclarationName(Name), TemplateParams,
1070 NewClass, PrevClassTemplate);
1071 NewClass->setDescribedClassTemplate(NewTemplate);
1073 if (ModulePrivateLoc.isValid())
1074 NewTemplate->setModulePrivate();
1076 // Build the type for the class template declaration now.
1077 QualType T = NewTemplate->getInjectedClassNameSpecialization();
1078 T = Context.getInjectedClassNameType(NewClass, T);
1079 assert(T->isDependentType() && "Class template type is not dependent?");
1082 // If we are providing an explicit specialization of a member that is a
1083 // class template, make a note of that.
1084 if (PrevClassTemplate &&
1085 PrevClassTemplate->getInstantiatedFromMemberTemplate())
1086 PrevClassTemplate->setMemberSpecialization();
1088 // Set the access specifier.
1089 if (!Invalid && TUK != TUK_Friend && NewTemplate->getDeclContext()->isRecord())
1090 SetMemberAccessSpecifier(NewTemplate, PrevClassTemplate, AS);
1092 // Set the lexical context of these templates
1093 NewClass->setLexicalDeclContext(CurContext);
1094 NewTemplate->setLexicalDeclContext(CurContext);
1096 if (TUK == TUK_Definition)
1097 NewClass->startDefinition();
1100 ProcessDeclAttributeList(S, NewClass, Attr);
1102 if (PrevClassTemplate)
1103 mergeDeclAttributes(NewClass, PrevClassTemplate->getTemplatedDecl());
1105 AddPushedVisibilityAttribute(NewClass);
1107 if (TUK != TUK_Friend) {
1108 // Per C++ [basic.scope.temp]p2, skip the template parameter scopes.
1110 while ((Outer->getFlags() & Scope::TemplateParamScope) != 0)
1111 Outer = Outer->getParent();
1112 PushOnScopeChains(NewTemplate, Outer);
1114 if (PrevClassTemplate && PrevClassTemplate->getAccess() != AS_none) {
1115 NewTemplate->setAccess(PrevClassTemplate->getAccess());
1116 NewClass->setAccess(PrevClassTemplate->getAccess());
1119 NewTemplate->setObjectOfFriendDecl();
1121 // Friend templates are visible in fairly strange ways.
1122 if (!CurContext->isDependentContext()) {
1123 DeclContext *DC = SemanticContext->getRedeclContext();
1124 DC->makeDeclVisibleInContext(NewTemplate);
1125 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC))
1126 PushOnScopeChains(NewTemplate, EnclosingScope,
1127 /* AddToContext = */ false);
1130 FriendDecl *Friend = FriendDecl::Create(
1131 Context, CurContext, NewClass->getLocation(), NewTemplate, FriendLoc);
1132 Friend->setAccess(AS_public);
1133 CurContext->addDecl(Friend);
1137 NewTemplate->setInvalidDecl();
1138 NewClass->setInvalidDecl();
1141 ActOnDocumentableDecl(NewTemplate);
1146 /// \brief Diagnose the presence of a default template argument on a
1147 /// template parameter, which is ill-formed in certain contexts.
1149 /// \returns true if the default template argument should be dropped.
1150 static bool DiagnoseDefaultTemplateArgument(Sema &S,
1151 Sema::TemplateParamListContext TPC,
1152 SourceLocation ParamLoc,
1153 SourceRange DefArgRange) {
1155 case Sema::TPC_ClassTemplate:
1156 case Sema::TPC_VarTemplate:
1157 case Sema::TPC_TypeAliasTemplate:
1160 case Sema::TPC_FunctionTemplate:
1161 case Sema::TPC_FriendFunctionTemplateDefinition:
1162 // C++ [temp.param]p9:
1163 // A default template-argument shall not be specified in a
1164 // function template declaration or a function template
1166 // If a friend function template declaration specifies a default
1167 // template-argument, that declaration shall be a definition and shall be
1168 // the only declaration of the function template in the translation unit.
1169 // (C++98/03 doesn't have this wording; see DR226).
1170 S.Diag(ParamLoc, S.getLangOpts().CPlusPlus11 ?
1171 diag::warn_cxx98_compat_template_parameter_default_in_function_template
1172 : diag::ext_template_parameter_default_in_function_template)
1176 case Sema::TPC_ClassTemplateMember:
1177 // C++0x [temp.param]p9:
1178 // A default template-argument shall not be specified in the
1179 // template-parameter-lists of the definition of a member of a
1180 // class template that appears outside of the member's class.
1181 S.Diag(ParamLoc, diag::err_template_parameter_default_template_member)
1185 case Sema::TPC_FriendClassTemplate:
1186 case Sema::TPC_FriendFunctionTemplate:
1187 // C++ [temp.param]p9:
1188 // A default template-argument shall not be specified in a
1189 // friend template declaration.
1190 S.Diag(ParamLoc, diag::err_template_parameter_default_friend_template)
1194 // FIXME: C++0x [temp.param]p9 allows default template-arguments
1195 // for friend function templates if there is only a single
1196 // declaration (and it is a definition). Strange!
1199 llvm_unreachable("Invalid TemplateParamListContext!");
1202 /// \brief Check for unexpanded parameter packs within the template parameters
1203 /// of a template template parameter, recursively.
1204 static bool DiagnoseUnexpandedParameterPacks(Sema &S,
1205 TemplateTemplateParmDecl *TTP) {
1206 // A template template parameter which is a parameter pack is also a pack
1208 if (TTP->isParameterPack())
1211 TemplateParameterList *Params = TTP->getTemplateParameters();
1212 for (unsigned I = 0, N = Params->size(); I != N; ++I) {
1213 NamedDecl *P = Params->getParam(I);
1214 if (NonTypeTemplateParmDecl *NTTP = dyn_cast<NonTypeTemplateParmDecl>(P)) {
1215 if (!NTTP->isParameterPack() &&
1216 S.DiagnoseUnexpandedParameterPack(NTTP->getLocation(),
1217 NTTP->getTypeSourceInfo(),
1218 Sema::UPPC_NonTypeTemplateParameterType))
1224 if (TemplateTemplateParmDecl *InnerTTP
1225 = dyn_cast<TemplateTemplateParmDecl>(P))
1226 if (DiagnoseUnexpandedParameterPacks(S, InnerTTP))
1233 /// \brief Checks the validity of a template parameter list, possibly
1234 /// considering the template parameter list from a previous
1237 /// If an "old" template parameter list is provided, it must be
1238 /// equivalent (per TemplateParameterListsAreEqual) to the "new"
1239 /// template parameter list.
1241 /// \param NewParams Template parameter list for a new template
1242 /// declaration. This template parameter list will be updated with any
1243 /// default arguments that are carried through from the previous
1244 /// template parameter list.
1246 /// \param OldParams If provided, template parameter list from a
1247 /// previous declaration of the same template. Default template
1248 /// arguments will be merged from the old template parameter list to
1249 /// the new template parameter list.
1251 /// \param TPC Describes the context in which we are checking the given
1252 /// template parameter list.
1254 /// \returns true if an error occurred, false otherwise.
1255 bool Sema::CheckTemplateParameterList(TemplateParameterList *NewParams,
1256 TemplateParameterList *OldParams,
1257 TemplateParamListContext TPC) {
1258 bool Invalid = false;
1260 // C++ [temp.param]p10:
1261 // The set of default template-arguments available for use with a
1262 // template declaration or definition is obtained by merging the
1263 // default arguments from the definition (if in scope) and all
1264 // declarations in scope in the same way default function
1265 // arguments are (8.3.6).
1266 bool SawDefaultArgument = false;
1267 SourceLocation PreviousDefaultArgLoc;
1269 // Dummy initialization to avoid warnings.
1270 TemplateParameterList::iterator OldParam = NewParams->end();
1272 OldParam = OldParams->begin();
1274 bool RemoveDefaultArguments = false;
1275 for (TemplateParameterList::iterator NewParam = NewParams->begin(),
1276 NewParamEnd = NewParams->end();
1277 NewParam != NewParamEnd; ++NewParam) {
1278 // Variables used to diagnose redundant default arguments
1279 bool RedundantDefaultArg = false;
1280 SourceLocation OldDefaultLoc;
1281 SourceLocation NewDefaultLoc;
1283 // Variable used to diagnose missing default arguments
1284 bool MissingDefaultArg = false;
1286 // Variable used to diagnose non-final parameter packs
1287 bool SawParameterPack = false;
1289 if (TemplateTypeParmDecl *NewTypeParm
1290 = dyn_cast<TemplateTypeParmDecl>(*NewParam)) {
1291 // Check the presence of a default argument here.
1292 if (NewTypeParm->hasDefaultArgument() &&
1293 DiagnoseDefaultTemplateArgument(*this, TPC,
1294 NewTypeParm->getLocation(),
1295 NewTypeParm->getDefaultArgumentInfo()->getTypeLoc()
1297 NewTypeParm->removeDefaultArgument();
1299 // Merge default arguments for template type parameters.
1300 TemplateTypeParmDecl *OldTypeParm
1301 = OldParams? cast<TemplateTypeParmDecl>(*OldParam) : nullptr;
1303 if (NewTypeParm->isParameterPack()) {
1304 assert(!NewTypeParm->hasDefaultArgument() &&
1305 "Parameter packs can't have a default argument!");
1306 SawParameterPack = true;
1307 } else if (OldTypeParm && OldTypeParm->hasDefaultArgument() &&
1308 NewTypeParm->hasDefaultArgument()) {
1309 OldDefaultLoc = OldTypeParm->getDefaultArgumentLoc();
1310 NewDefaultLoc = NewTypeParm->getDefaultArgumentLoc();
1311 SawDefaultArgument = true;
1312 RedundantDefaultArg = true;
1313 PreviousDefaultArgLoc = NewDefaultLoc;
1314 } else if (OldTypeParm && OldTypeParm->hasDefaultArgument()) {
1315 // Merge the default argument from the old declaration to the
1317 NewTypeParm->setDefaultArgument(OldTypeParm->getDefaultArgumentInfo(),
1319 PreviousDefaultArgLoc = OldTypeParm->getDefaultArgumentLoc();
1320 } else if (NewTypeParm->hasDefaultArgument()) {
1321 SawDefaultArgument = true;
1322 PreviousDefaultArgLoc = NewTypeParm->getDefaultArgumentLoc();
1323 } else if (SawDefaultArgument)
1324 MissingDefaultArg = true;
1325 } else if (NonTypeTemplateParmDecl *NewNonTypeParm
1326 = dyn_cast<NonTypeTemplateParmDecl>(*NewParam)) {
1327 // Check for unexpanded parameter packs.
1328 if (!NewNonTypeParm->isParameterPack() &&
1329 DiagnoseUnexpandedParameterPack(NewNonTypeParm->getLocation(),
1330 NewNonTypeParm->getTypeSourceInfo(),
1331 UPPC_NonTypeTemplateParameterType)) {
1336 // Check the presence of a default argument here.
1337 if (NewNonTypeParm->hasDefaultArgument() &&
1338 DiagnoseDefaultTemplateArgument(*this, TPC,
1339 NewNonTypeParm->getLocation(),
1340 NewNonTypeParm->getDefaultArgument()->getSourceRange())) {
1341 NewNonTypeParm->removeDefaultArgument();
1344 // Merge default arguments for non-type template parameters
1345 NonTypeTemplateParmDecl *OldNonTypeParm
1346 = OldParams? cast<NonTypeTemplateParmDecl>(*OldParam) : nullptr;
1347 if (NewNonTypeParm->isParameterPack()) {
1348 assert(!NewNonTypeParm->hasDefaultArgument() &&
1349 "Parameter packs can't have a default argument!");
1350 if (!NewNonTypeParm->isPackExpansion())
1351 SawParameterPack = true;
1352 } else if (OldNonTypeParm && OldNonTypeParm->hasDefaultArgument() &&
1353 NewNonTypeParm->hasDefaultArgument()) {
1354 OldDefaultLoc = OldNonTypeParm->getDefaultArgumentLoc();
1355 NewDefaultLoc = NewNonTypeParm->getDefaultArgumentLoc();
1356 SawDefaultArgument = true;
1357 RedundantDefaultArg = true;
1358 PreviousDefaultArgLoc = NewDefaultLoc;
1359 } else if (OldNonTypeParm && OldNonTypeParm->hasDefaultArgument()) {
1360 // Merge the default argument from the old declaration to the
1362 // FIXME: We need to create a new kind of "default argument"
1363 // expression that points to a previous non-type template
1365 NewNonTypeParm->setDefaultArgument(
1366 OldNonTypeParm->getDefaultArgument(),
1367 /*Inherited=*/ true);
1368 PreviousDefaultArgLoc = OldNonTypeParm->getDefaultArgumentLoc();
1369 } else if (NewNonTypeParm->hasDefaultArgument()) {
1370 SawDefaultArgument = true;
1371 PreviousDefaultArgLoc = NewNonTypeParm->getDefaultArgumentLoc();
1372 } else if (SawDefaultArgument)
1373 MissingDefaultArg = true;
1375 TemplateTemplateParmDecl *NewTemplateParm
1376 = cast<TemplateTemplateParmDecl>(*NewParam);
1378 // Check for unexpanded parameter packs, recursively.
1379 if (::DiagnoseUnexpandedParameterPacks(*this, NewTemplateParm)) {
1384 // Check the presence of a default argument here.
1385 if (NewTemplateParm->hasDefaultArgument() &&
1386 DiagnoseDefaultTemplateArgument(*this, TPC,
1387 NewTemplateParm->getLocation(),
1388 NewTemplateParm->getDefaultArgument().getSourceRange()))
1389 NewTemplateParm->removeDefaultArgument();
1391 // Merge default arguments for template template parameters
1392 TemplateTemplateParmDecl *OldTemplateParm
1393 = OldParams? cast<TemplateTemplateParmDecl>(*OldParam) : nullptr;
1394 if (NewTemplateParm->isParameterPack()) {
1395 assert(!NewTemplateParm->hasDefaultArgument() &&
1396 "Parameter packs can't have a default argument!");
1397 if (!NewTemplateParm->isPackExpansion())
1398 SawParameterPack = true;
1399 } else if (OldTemplateParm && OldTemplateParm->hasDefaultArgument() &&
1400 NewTemplateParm->hasDefaultArgument()) {
1401 OldDefaultLoc = OldTemplateParm->getDefaultArgument().getLocation();
1402 NewDefaultLoc = NewTemplateParm->getDefaultArgument().getLocation();
1403 SawDefaultArgument = true;
1404 RedundantDefaultArg = true;
1405 PreviousDefaultArgLoc = NewDefaultLoc;
1406 } else if (OldTemplateParm && OldTemplateParm->hasDefaultArgument()) {
1407 // Merge the default argument from the old declaration to the
1409 // FIXME: We need to create a new kind of "default argument" expression
1410 // that points to a previous template template parameter.
1411 NewTemplateParm->setDefaultArgument(
1412 OldTemplateParm->getDefaultArgument(),
1413 /*Inherited=*/ true);
1414 PreviousDefaultArgLoc
1415 = OldTemplateParm->getDefaultArgument().getLocation();
1416 } else if (NewTemplateParm->hasDefaultArgument()) {
1417 SawDefaultArgument = true;
1418 PreviousDefaultArgLoc
1419 = NewTemplateParm->getDefaultArgument().getLocation();
1420 } else if (SawDefaultArgument)
1421 MissingDefaultArg = true;
1424 // C++11 [temp.param]p11:
1425 // If a template parameter of a primary class template or alias template
1426 // is a template parameter pack, it shall be the last template parameter.
1427 if (SawParameterPack && (NewParam + 1) != NewParamEnd &&
1428 (TPC == TPC_ClassTemplate || TPC == TPC_VarTemplate ||
1429 TPC == TPC_TypeAliasTemplate)) {
1430 Diag((*NewParam)->getLocation(),
1431 diag::err_template_param_pack_must_be_last_template_parameter);
1435 if (RedundantDefaultArg) {
1436 // C++ [temp.param]p12:
1437 // A template-parameter shall not be given default arguments
1438 // by two different declarations in the same scope.
1439 Diag(NewDefaultLoc, diag::err_template_param_default_arg_redefinition);
1440 Diag(OldDefaultLoc, diag::note_template_param_prev_default_arg);
1442 } else if (MissingDefaultArg && TPC != TPC_FunctionTemplate) {
1443 // C++ [temp.param]p11:
1444 // If a template-parameter of a class template has a default
1445 // template-argument, each subsequent template-parameter shall either
1446 // have a default template-argument supplied or be a template parameter
1448 Diag((*NewParam)->getLocation(),
1449 diag::err_template_param_default_arg_missing);
1450 Diag(PreviousDefaultArgLoc, diag::note_template_param_prev_default_arg);
1452 RemoveDefaultArguments = true;
1455 // If we have an old template parameter list that we're merging
1456 // in, move on to the next parameter.
1461 // We were missing some default arguments at the end of the list, so remove
1462 // all of the default arguments.
1463 if (RemoveDefaultArguments) {
1464 for (TemplateParameterList::iterator NewParam = NewParams->begin(),
1465 NewParamEnd = NewParams->end();
1466 NewParam != NewParamEnd; ++NewParam) {
1467 if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(*NewParam))
1468 TTP->removeDefaultArgument();
1469 else if (NonTypeTemplateParmDecl *NTTP
1470 = dyn_cast<NonTypeTemplateParmDecl>(*NewParam))
1471 NTTP->removeDefaultArgument();
1473 cast<TemplateTemplateParmDecl>(*NewParam)->removeDefaultArgument();
1482 /// A class which looks for a use of a certain level of template
1484 struct DependencyChecker : RecursiveASTVisitor<DependencyChecker> {
1485 typedef RecursiveASTVisitor<DependencyChecker> super;
1489 SourceLocation MatchLoc;
1491 DependencyChecker(unsigned Depth) : Depth(Depth), Match(false) {}
1493 DependencyChecker(TemplateParameterList *Params) : Match(false) {
1494 NamedDecl *ND = Params->getParam(0);
1495 if (TemplateTypeParmDecl *PD = dyn_cast<TemplateTypeParmDecl>(ND)) {
1496 Depth = PD->getDepth();
1497 } else if (NonTypeTemplateParmDecl *PD =
1498 dyn_cast<NonTypeTemplateParmDecl>(ND)) {
1499 Depth = PD->getDepth();
1501 Depth = cast<TemplateTemplateParmDecl>(ND)->getDepth();
1505 bool Matches(unsigned ParmDepth, SourceLocation Loc = SourceLocation()) {
1506 if (ParmDepth >= Depth) {
1514 bool VisitTemplateTypeParmTypeLoc(TemplateTypeParmTypeLoc TL) {
1515 return !Matches(TL.getTypePtr()->getDepth(), TL.getNameLoc());
1518 bool VisitTemplateTypeParmType(const TemplateTypeParmType *T) {
1519 return !Matches(T->getDepth());
1522 bool TraverseTemplateName(TemplateName N) {
1523 if (TemplateTemplateParmDecl *PD =
1524 dyn_cast_or_null<TemplateTemplateParmDecl>(N.getAsTemplateDecl()))
1525 if (Matches(PD->getDepth()))
1527 return super::TraverseTemplateName(N);
1530 bool VisitDeclRefExpr(DeclRefExpr *E) {
1531 if (NonTypeTemplateParmDecl *PD =
1532 dyn_cast<NonTypeTemplateParmDecl>(E->getDecl()))
1533 if (Matches(PD->getDepth(), E->getExprLoc()))
1535 return super::VisitDeclRefExpr(E);
1538 bool VisitSubstTemplateTypeParmType(const SubstTemplateTypeParmType *T) {
1539 return TraverseType(T->getReplacementType());
1543 VisitSubstTemplateTypeParmPackType(const SubstTemplateTypeParmPackType *T) {
1544 return TraverseTemplateArgument(T->getArgumentPack());
1547 bool TraverseInjectedClassNameType(const InjectedClassNameType *T) {
1548 return TraverseType(T->getInjectedSpecializationType());
1553 /// Determines whether a given type depends on the given parameter
1556 DependsOnTemplateParameters(QualType T, TemplateParameterList *Params) {
1557 DependencyChecker Checker(Params);
1558 Checker.TraverseType(T);
1559 return Checker.Match;
1562 // Find the source range corresponding to the named type in the given
1563 // nested-name-specifier, if any.
1564 static SourceRange getRangeOfTypeInNestedNameSpecifier(ASTContext &Context,
1566 const CXXScopeSpec &SS) {
1567 NestedNameSpecifierLoc NNSLoc(SS.getScopeRep(), SS.location_data());
1568 while (NestedNameSpecifier *NNS = NNSLoc.getNestedNameSpecifier()) {
1569 if (const Type *CurType = NNS->getAsType()) {
1570 if (Context.hasSameUnqualifiedType(T, QualType(CurType, 0)))
1571 return NNSLoc.getTypeLoc().getSourceRange();
1575 NNSLoc = NNSLoc.getPrefix();
1578 return SourceRange();
1581 /// \brief Match the given template parameter lists to the given scope
1582 /// specifier, returning the template parameter list that applies to the
1585 /// \param DeclStartLoc the start of the declaration that has a scope
1586 /// specifier or a template parameter list.
1588 /// \param DeclLoc The location of the declaration itself.
1590 /// \param SS the scope specifier that will be matched to the given template
1591 /// parameter lists. This scope specifier precedes a qualified name that is
1594 /// \param TemplateId The template-id following the scope specifier, if there
1595 /// is one. Used to check for a missing 'template<>'.
1597 /// \param ParamLists the template parameter lists, from the outermost to the
1598 /// innermost template parameter lists.
1600 /// \param IsFriend Whether to apply the slightly different rules for
1601 /// matching template parameters to scope specifiers in friend
1604 /// \param IsExplicitSpecialization will be set true if the entity being
1605 /// declared is an explicit specialization, false otherwise.
1607 /// \returns the template parameter list, if any, that corresponds to the
1608 /// name that is preceded by the scope specifier @p SS. This template
1609 /// parameter list may have template parameters (if we're declaring a
1610 /// template) or may have no template parameters (if we're declaring a
1611 /// template specialization), or may be NULL (if what we're declaring isn't
1612 /// itself a template).
1613 TemplateParameterList *Sema::MatchTemplateParametersToScopeSpecifier(
1614 SourceLocation DeclStartLoc, SourceLocation DeclLoc, const CXXScopeSpec &SS,
1615 TemplateIdAnnotation *TemplateId,
1616 ArrayRef<TemplateParameterList *> ParamLists, bool IsFriend,
1617 bool &IsExplicitSpecialization, bool &Invalid) {
1618 IsExplicitSpecialization = false;
1621 // The sequence of nested types to which we will match up the template
1622 // parameter lists. We first build this list by starting with the type named
1623 // by the nested-name-specifier and walking out until we run out of types.
1624 SmallVector<QualType, 4> NestedTypes;
1626 if (SS.getScopeRep()) {
1627 if (CXXRecordDecl *Record
1628 = dyn_cast_or_null<CXXRecordDecl>(computeDeclContext(SS, true)))
1629 T = Context.getTypeDeclType(Record);
1631 T = QualType(SS.getScopeRep()->getAsType(), 0);
1634 // If we found an explicit specialization that prevents us from needing
1635 // 'template<>' headers, this will be set to the location of that
1636 // explicit specialization.
1637 SourceLocation ExplicitSpecLoc;
1639 while (!T.isNull()) {
1640 NestedTypes.push_back(T);
1642 // Retrieve the parent of a record type.
1643 if (CXXRecordDecl *Record = T->getAsCXXRecordDecl()) {
1644 // If this type is an explicit specialization, we're done.
1645 if (ClassTemplateSpecializationDecl *Spec
1646 = dyn_cast<ClassTemplateSpecializationDecl>(Record)) {
1647 if (!isa<ClassTemplatePartialSpecializationDecl>(Spec) &&
1648 Spec->getSpecializationKind() == TSK_ExplicitSpecialization) {
1649 ExplicitSpecLoc = Spec->getLocation();
1652 } else if (Record->getTemplateSpecializationKind()
1653 == TSK_ExplicitSpecialization) {
1654 ExplicitSpecLoc = Record->getLocation();
1658 if (TypeDecl *Parent = dyn_cast<TypeDecl>(Record->getParent()))
1659 T = Context.getTypeDeclType(Parent);
1665 if (const TemplateSpecializationType *TST
1666 = T->getAs<TemplateSpecializationType>()) {
1667 if (TemplateDecl *Template = TST->getTemplateName().getAsTemplateDecl()) {
1668 if (TypeDecl *Parent = dyn_cast<TypeDecl>(Template->getDeclContext()))
1669 T = Context.getTypeDeclType(Parent);
1676 // Look one step prior in a dependent template specialization type.
1677 if (const DependentTemplateSpecializationType *DependentTST
1678 = T->getAs<DependentTemplateSpecializationType>()) {
1679 if (NestedNameSpecifier *NNS = DependentTST->getQualifier())
1680 T = QualType(NNS->getAsType(), 0);
1686 // Look one step prior in a dependent name type.
1687 if (const DependentNameType *DependentName = T->getAs<DependentNameType>()){
1688 if (NestedNameSpecifier *NNS = DependentName->getQualifier())
1689 T = QualType(NNS->getAsType(), 0);
1695 // Retrieve the parent of an enumeration type.
1696 if (const EnumType *EnumT = T->getAs<EnumType>()) {
1697 // FIXME: Forward-declared enums require a TSK_ExplicitSpecialization
1699 EnumDecl *Enum = EnumT->getDecl();
1701 // Get to the parent type.
1702 if (TypeDecl *Parent = dyn_cast<TypeDecl>(Enum->getParent()))
1703 T = Context.getTypeDeclType(Parent);
1711 // Reverse the nested types list, since we want to traverse from the outermost
1712 // to the innermost while checking template-parameter-lists.
1713 std::reverse(NestedTypes.begin(), NestedTypes.end());
1715 // C++0x [temp.expl.spec]p17:
1716 // A member or a member template may be nested within many
1717 // enclosing class templates. In an explicit specialization for
1718 // such a member, the member declaration shall be preceded by a
1719 // template<> for each enclosing class template that is
1720 // explicitly specialized.
1721 bool SawNonEmptyTemplateParameterList = false;
1723 auto CheckExplicitSpecialization = [&](SourceRange Range, bool Recovery) {
1724 if (SawNonEmptyTemplateParameterList) {
1725 Diag(DeclLoc, diag::err_specialize_member_of_template)
1726 << !Recovery << Range;
1728 IsExplicitSpecialization = false;
1735 auto DiagnoseMissingExplicitSpecialization = [&] (SourceRange Range) {
1736 // Check that we can have an explicit specialization here.
1737 if (CheckExplicitSpecialization(Range, true))
1740 // We don't have a template header, but we should.
1741 SourceLocation ExpectedTemplateLoc;
1742 if (!ParamLists.empty())
1743 ExpectedTemplateLoc = ParamLists[0]->getTemplateLoc();
1745 ExpectedTemplateLoc = DeclStartLoc;
1747 Diag(DeclLoc, diag::err_template_spec_needs_header)
1749 << FixItHint::CreateInsertion(ExpectedTemplateLoc, "template<> ");
1753 unsigned ParamIdx = 0;
1754 for (unsigned TypeIdx = 0, NumTypes = NestedTypes.size(); TypeIdx != NumTypes;
1756 T = NestedTypes[TypeIdx];
1758 // Whether we expect a 'template<>' header.
1759 bool NeedEmptyTemplateHeader = false;
1761 // Whether we expect a template header with parameters.
1762 bool NeedNonemptyTemplateHeader = false;
1764 // For a dependent type, the set of template parameters that we
1766 TemplateParameterList *ExpectedTemplateParams = nullptr;
1768 // C++0x [temp.expl.spec]p15:
1769 // A member or a member template may be nested within many enclosing
1770 // class templates. In an explicit specialization for such a member, the
1771 // member declaration shall be preceded by a template<> for each
1772 // enclosing class template that is explicitly specialized.
1773 if (CXXRecordDecl *Record = T->getAsCXXRecordDecl()) {
1774 if (ClassTemplatePartialSpecializationDecl *Partial
1775 = dyn_cast<ClassTemplatePartialSpecializationDecl>(Record)) {
1776 ExpectedTemplateParams = Partial->getTemplateParameters();
1777 NeedNonemptyTemplateHeader = true;
1778 } else if (Record->isDependentType()) {
1779 if (Record->getDescribedClassTemplate()) {
1780 ExpectedTemplateParams = Record->getDescribedClassTemplate()
1781 ->getTemplateParameters();
1782 NeedNonemptyTemplateHeader = true;
1784 } else if (ClassTemplateSpecializationDecl *Spec
1785 = dyn_cast<ClassTemplateSpecializationDecl>(Record)) {
1786 // C++0x [temp.expl.spec]p4:
1787 // Members of an explicitly specialized class template are defined
1788 // in the same manner as members of normal classes, and not using
1789 // the template<> syntax.
1790 if (Spec->getSpecializationKind() != TSK_ExplicitSpecialization)
1791 NeedEmptyTemplateHeader = true;
1794 } else if (Record->getTemplateSpecializationKind()) {
1795 if (Record->getTemplateSpecializationKind()
1796 != TSK_ExplicitSpecialization &&
1797 TypeIdx == NumTypes - 1)
1798 IsExplicitSpecialization = true;
1802 } else if (const TemplateSpecializationType *TST
1803 = T->getAs<TemplateSpecializationType>()) {
1804 if (TemplateDecl *Template = TST->getTemplateName().getAsTemplateDecl()) {
1805 ExpectedTemplateParams = Template->getTemplateParameters();
1806 NeedNonemptyTemplateHeader = true;
1808 } else if (T->getAs<DependentTemplateSpecializationType>()) {
1809 // FIXME: We actually could/should check the template arguments here
1810 // against the corresponding template parameter list.
1811 NeedNonemptyTemplateHeader = false;
1814 // C++ [temp.expl.spec]p16:
1815 // In an explicit specialization declaration for a member of a class
1816 // template or a member template that ap- pears in namespace scope, the
1817 // member template and some of its enclosing class templates may remain
1818 // unspecialized, except that the declaration shall not explicitly
1819 // specialize a class member template if its en- closing class templates
1820 // are not explicitly specialized as well.
1821 if (ParamIdx < ParamLists.size()) {
1822 if (ParamLists[ParamIdx]->size() == 0) {
1823 if (CheckExplicitSpecialization(ParamLists[ParamIdx]->getSourceRange(),
1827 SawNonEmptyTemplateParameterList = true;
1830 if (NeedEmptyTemplateHeader) {
1831 // If we're on the last of the types, and we need a 'template<>' header
1832 // here, then it's an explicit specialization.
1833 if (TypeIdx == NumTypes - 1)
1834 IsExplicitSpecialization = true;
1836 if (ParamIdx < ParamLists.size()) {
1837 if (ParamLists[ParamIdx]->size() > 0) {
1838 // The header has template parameters when it shouldn't. Complain.
1839 Diag(ParamLists[ParamIdx]->getTemplateLoc(),
1840 diag::err_template_param_list_matches_nontemplate)
1842 << SourceRange(ParamLists[ParamIdx]->getLAngleLoc(),
1843 ParamLists[ParamIdx]->getRAngleLoc())
1844 << getRangeOfTypeInNestedNameSpecifier(Context, T, SS);
1849 // Consume this template header.
1855 if (DiagnoseMissingExplicitSpecialization(
1856 getRangeOfTypeInNestedNameSpecifier(Context, T, SS)))
1862 if (NeedNonemptyTemplateHeader) {
1863 // In friend declarations we can have template-ids which don't
1864 // depend on the corresponding template parameter lists. But
1865 // assume that empty parameter lists are supposed to match this
1867 if (IsFriend && T->isDependentType()) {
1868 if (ParamIdx < ParamLists.size() &&
1869 DependsOnTemplateParameters(T, ParamLists[ParamIdx]))
1870 ExpectedTemplateParams = nullptr;
1875 if (ParamIdx < ParamLists.size()) {
1876 // Check the template parameter list, if we can.
1877 if (ExpectedTemplateParams &&
1878 !TemplateParameterListsAreEqual(ParamLists[ParamIdx],
1879 ExpectedTemplateParams,
1880 true, TPL_TemplateMatch))
1884 CheckTemplateParameterList(ParamLists[ParamIdx], nullptr,
1885 TPC_ClassTemplateMember))
1892 Diag(DeclLoc, diag::err_template_spec_needs_template_parameters)
1894 << getRangeOfTypeInNestedNameSpecifier(Context, T, SS);
1900 // If there were at least as many template-ids as there were template
1901 // parameter lists, then there are no template parameter lists remaining for
1902 // the declaration itself.
1903 if (ParamIdx >= ParamLists.size()) {
1904 if (TemplateId && !IsFriend) {
1905 // We don't have a template header for the declaration itself, but we
1907 IsExplicitSpecialization = true;
1908 DiagnoseMissingExplicitSpecialization(SourceRange(TemplateId->LAngleLoc,
1909 TemplateId->RAngleLoc));
1911 // Fabricate an empty template parameter list for the invented header.
1912 return TemplateParameterList::Create(Context, SourceLocation(),
1913 SourceLocation(), nullptr, 0,
1920 // If there were too many template parameter lists, complain about that now.
1921 if (ParamIdx < ParamLists.size() - 1) {
1922 bool HasAnyExplicitSpecHeader = false;
1923 bool AllExplicitSpecHeaders = true;
1924 for (unsigned I = ParamIdx, E = ParamLists.size() - 1; I != E; ++I) {
1925 if (ParamLists[I]->size() == 0)
1926 HasAnyExplicitSpecHeader = true;
1928 AllExplicitSpecHeaders = false;
1931 Diag(ParamLists[ParamIdx]->getTemplateLoc(),
1932 AllExplicitSpecHeaders ? diag::warn_template_spec_extra_headers
1933 : diag::err_template_spec_extra_headers)
1934 << SourceRange(ParamLists[ParamIdx]->getTemplateLoc(),
1935 ParamLists[ParamLists.size() - 2]->getRAngleLoc());
1937 // If there was a specialization somewhere, such that 'template<>' is
1938 // not required, and there were any 'template<>' headers, note where the
1939 // specialization occurred.
1940 if (ExplicitSpecLoc.isValid() && HasAnyExplicitSpecHeader)
1941 Diag(ExplicitSpecLoc,
1942 diag::note_explicit_template_spec_does_not_need_header)
1943 << NestedTypes.back();
1945 // We have a template parameter list with no corresponding scope, which
1946 // means that the resulting template declaration can't be instantiated
1947 // properly (we'll end up with dependent nodes when we shouldn't).
1948 if (!AllExplicitSpecHeaders)
1952 // C++ [temp.expl.spec]p16:
1953 // In an explicit specialization declaration for a member of a class
1954 // template or a member template that ap- pears in namespace scope, the
1955 // member template and some of its enclosing class templates may remain
1956 // unspecialized, except that the declaration shall not explicitly
1957 // specialize a class member template if its en- closing class templates
1958 // are not explicitly specialized as well.
1959 if (ParamLists.back()->size() == 0 &&
1960 CheckExplicitSpecialization(ParamLists[ParamIdx]->getSourceRange(),
1964 // Return the last template parameter list, which corresponds to the
1965 // entity being declared.
1966 return ParamLists.back();
1969 void Sema::NoteAllFoundTemplates(TemplateName Name) {
1970 if (TemplateDecl *Template = Name.getAsTemplateDecl()) {
1971 Diag(Template->getLocation(), diag::note_template_declared_here)
1972 << (isa<FunctionTemplateDecl>(Template)
1974 : isa<ClassTemplateDecl>(Template)
1976 : isa<VarTemplateDecl>(Template)
1978 : isa<TypeAliasTemplateDecl>(Template) ? 3 : 4)
1979 << Template->getDeclName();
1983 if (OverloadedTemplateStorage *OST = Name.getAsOverloadedTemplate()) {
1984 for (OverloadedTemplateStorage::iterator I = OST->begin(),
1987 Diag((*I)->getLocation(), diag::note_template_declared_here)
1988 << 0 << (*I)->getDeclName();
1994 QualType Sema::CheckTemplateIdType(TemplateName Name,
1995 SourceLocation TemplateLoc,
1996 TemplateArgumentListInfo &TemplateArgs) {
1997 DependentTemplateName *DTN
1998 = Name.getUnderlying().getAsDependentTemplateName();
1999 if (DTN && DTN->isIdentifier())
2000 // When building a template-id where the template-name is dependent,
2001 // assume the template is a type template. Either our assumption is
2002 // correct, or the code is ill-formed and will be diagnosed when the
2003 // dependent name is substituted.
2004 return Context.getDependentTemplateSpecializationType(ETK_None,
2005 DTN->getQualifier(),
2006 DTN->getIdentifier(),
2009 TemplateDecl *Template = Name.getAsTemplateDecl();
2010 if (!Template || isa<FunctionTemplateDecl>(Template) ||
2011 isa<VarTemplateDecl>(Template)) {
2012 // We might have a substituted template template parameter pack. If so,
2013 // build a template specialization type for it.
2014 if (Name.getAsSubstTemplateTemplateParmPack())
2015 return Context.getTemplateSpecializationType(Name, TemplateArgs);
2017 Diag(TemplateLoc, diag::err_template_id_not_a_type)
2019 NoteAllFoundTemplates(Name);
2023 // Check that the template argument list is well-formed for this
2025 SmallVector<TemplateArgument, 4> Converted;
2026 if (CheckTemplateArgumentList(Template, TemplateLoc, TemplateArgs,
2032 bool InstantiationDependent = false;
2033 if (TypeAliasTemplateDecl *AliasTemplate =
2034 dyn_cast<TypeAliasTemplateDecl>(Template)) {
2035 // Find the canonical type for this type alias template specialization.
2036 TypeAliasDecl *Pattern = AliasTemplate->getTemplatedDecl();
2037 if (Pattern->isInvalidDecl())
2040 TemplateArgumentList TemplateArgs(TemplateArgumentList::OnStack,
2041 Converted.data(), Converted.size());
2043 // Only substitute for the innermost template argument list.
2044 MultiLevelTemplateArgumentList TemplateArgLists;
2045 TemplateArgLists.addOuterTemplateArguments(&TemplateArgs);
2046 unsigned Depth = AliasTemplate->getTemplateParameters()->getDepth();
2047 for (unsigned I = 0; I < Depth; ++I)
2048 TemplateArgLists.addOuterTemplateArguments(None);
2050 LocalInstantiationScope Scope(*this);
2051 InstantiatingTemplate Inst(*this, TemplateLoc, Template);
2052 if (Inst.isInvalid())
2055 CanonType = SubstType(Pattern->getUnderlyingType(),
2056 TemplateArgLists, AliasTemplate->getLocation(),
2057 AliasTemplate->getDeclName());
2058 if (CanonType.isNull())
2060 } else if (Name.isDependent() ||
2061 TemplateSpecializationType::anyDependentTemplateArguments(
2062 TemplateArgs, InstantiationDependent)) {
2063 // This class template specialization is a dependent
2064 // type. Therefore, its canonical type is another class template
2065 // specialization type that contains all of the converted
2066 // arguments in canonical form. This ensures that, e.g., A<T> and
2067 // A<T, T> have identical types when A is declared as:
2069 // template<typename T, typename U = T> struct A;
2070 TemplateName CanonName = Context.getCanonicalTemplateName(Name);
2071 CanonType = Context.getTemplateSpecializationType(CanonName,
2075 // FIXME: CanonType is not actually the canonical type, and unfortunately
2076 // it is a TemplateSpecializationType that we will never use again.
2077 // In the future, we need to teach getTemplateSpecializationType to only
2078 // build the canonical type and return that to us.
2079 CanonType = Context.getCanonicalType(CanonType);
2081 // This might work out to be a current instantiation, in which
2082 // case the canonical type needs to be the InjectedClassNameType.
2084 // TODO: in theory this could be a simple hashtable lookup; most
2085 // changes to CurContext don't change the set of current
2087 if (isa<ClassTemplateDecl>(Template)) {
2088 for (DeclContext *Ctx = CurContext; Ctx; Ctx = Ctx->getLookupParent()) {
2089 // If we get out to a namespace, we're done.
2090 if (Ctx->isFileContext()) break;
2092 // If this isn't a record, keep looking.
2093 CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Ctx);
2094 if (!Record) continue;
2096 // Look for one of the two cases with InjectedClassNameTypes
2097 // and check whether it's the same template.
2098 if (!isa<ClassTemplatePartialSpecializationDecl>(Record) &&
2099 !Record->getDescribedClassTemplate())
2102 // Fetch the injected class name type and check whether its
2103 // injected type is equal to the type we just built.
2104 QualType ICNT = Context.getTypeDeclType(Record);
2105 QualType Injected = cast<InjectedClassNameType>(ICNT)
2106 ->getInjectedSpecializationType();
2108 if (CanonType != Injected->getCanonicalTypeInternal())
2111 // If so, the canonical type of this TST is the injected
2112 // class name type of the record we just found.
2113 assert(ICNT.isCanonical());
2118 } else if (ClassTemplateDecl *ClassTemplate
2119 = dyn_cast<ClassTemplateDecl>(Template)) {
2120 // Find the class template specialization declaration that
2121 // corresponds to these arguments.
2122 void *InsertPos = nullptr;
2123 ClassTemplateSpecializationDecl *Decl
2124 = ClassTemplate->findSpecialization(Converted, InsertPos);
2126 // This is the first time we have referenced this class template
2127 // specialization. Create the canonical declaration and add it to
2128 // the set of specializations.
2129 Decl = ClassTemplateSpecializationDecl::Create(Context,
2130 ClassTemplate->getTemplatedDecl()->getTagKind(),
2131 ClassTemplate->getDeclContext(),
2132 ClassTemplate->getTemplatedDecl()->getLocStart(),
2133 ClassTemplate->getLocation(),
2136 Converted.size(), nullptr);
2137 ClassTemplate->AddSpecialization(Decl, InsertPos);
2138 if (ClassTemplate->isOutOfLine())
2139 Decl->setLexicalDeclContext(ClassTemplate->getLexicalDeclContext());
2142 // Diagnose uses of this specialization.
2143 (void)DiagnoseUseOfDecl(Decl, TemplateLoc);
2145 CanonType = Context.getTypeDeclType(Decl);
2146 assert(isa<RecordType>(CanonType) &&
2147 "type of non-dependent specialization is not a RecordType");
2150 // Build the fully-sugared type for this class template
2151 // specialization, which refers back to the class template
2152 // specialization we created or found.
2153 return Context.getTemplateSpecializationType(Name, TemplateArgs, CanonType);
2157 Sema::ActOnTemplateIdType(CXXScopeSpec &SS, SourceLocation TemplateKWLoc,
2158 TemplateTy TemplateD, SourceLocation TemplateLoc,
2159 SourceLocation LAngleLoc,
2160 ASTTemplateArgsPtr TemplateArgsIn,
2161 SourceLocation RAngleLoc,
2162 bool IsCtorOrDtorName) {
2166 TemplateName Template = TemplateD.get();
2168 // Translate the parser's template argument list in our AST format.
2169 TemplateArgumentListInfo TemplateArgs(LAngleLoc, RAngleLoc);
2170 translateTemplateArguments(TemplateArgsIn, TemplateArgs);
2172 if (DependentTemplateName *DTN = Template.getAsDependentTemplateName()) {
2174 = Context.getDependentTemplateSpecializationType(ETK_None,
2175 DTN->getQualifier(),
2176 DTN->getIdentifier(),
2178 // Build type-source information.
2180 DependentTemplateSpecializationTypeLoc SpecTL
2181 = TLB.push<DependentTemplateSpecializationTypeLoc>(T);
2182 SpecTL.setElaboratedKeywordLoc(SourceLocation());
2183 SpecTL.setQualifierLoc(SS.getWithLocInContext(Context));
2184 SpecTL.setTemplateKeywordLoc(TemplateKWLoc);
2185 SpecTL.setTemplateNameLoc(TemplateLoc);
2186 SpecTL.setLAngleLoc(LAngleLoc);
2187 SpecTL.setRAngleLoc(RAngleLoc);
2188 for (unsigned I = 0, N = SpecTL.getNumArgs(); I != N; ++I)
2189 SpecTL.setArgLocInfo(I, TemplateArgs[I].getLocInfo());
2190 return CreateParsedType(T, TLB.getTypeSourceInfo(Context, T));
2193 QualType Result = CheckTemplateIdType(Template, TemplateLoc, TemplateArgs);
2195 if (Result.isNull())
2198 // Build type-source information.
2200 TemplateSpecializationTypeLoc SpecTL
2201 = TLB.push<TemplateSpecializationTypeLoc>(Result);
2202 SpecTL.setTemplateKeywordLoc(TemplateKWLoc);
2203 SpecTL.setTemplateNameLoc(TemplateLoc);
2204 SpecTL.setLAngleLoc(LAngleLoc);
2205 SpecTL.setRAngleLoc(RAngleLoc);
2206 for (unsigned i = 0, e = SpecTL.getNumArgs(); i != e; ++i)
2207 SpecTL.setArgLocInfo(i, TemplateArgs[i].getLocInfo());
2209 // NOTE: avoid constructing an ElaboratedTypeLoc if this is a
2210 // constructor or destructor name (in such a case, the scope specifier
2211 // will be attached to the enclosing Decl or Expr node).
2212 if (SS.isNotEmpty() && !IsCtorOrDtorName) {
2213 // Create an elaborated-type-specifier containing the nested-name-specifier.
2214 Result = Context.getElaboratedType(ETK_None, SS.getScopeRep(), Result);
2215 ElaboratedTypeLoc ElabTL = TLB.push<ElaboratedTypeLoc>(Result);
2216 ElabTL.setElaboratedKeywordLoc(SourceLocation());
2217 ElabTL.setQualifierLoc(SS.getWithLocInContext(Context));
2220 return CreateParsedType(Result, TLB.getTypeSourceInfo(Context, Result));
2223 TypeResult Sema::ActOnTagTemplateIdType(TagUseKind TUK,
2224 TypeSpecifierType TagSpec,
2225 SourceLocation TagLoc,
2227 SourceLocation TemplateKWLoc,
2228 TemplateTy TemplateD,
2229 SourceLocation TemplateLoc,
2230 SourceLocation LAngleLoc,
2231 ASTTemplateArgsPtr TemplateArgsIn,
2232 SourceLocation RAngleLoc) {
2233 TemplateName Template = TemplateD.get();
2235 // Translate the parser's template argument list in our AST format.
2236 TemplateArgumentListInfo TemplateArgs(LAngleLoc, RAngleLoc);
2237 translateTemplateArguments(TemplateArgsIn, TemplateArgs);
2239 // Determine the tag kind
2240 TagTypeKind TagKind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec);
2241 ElaboratedTypeKeyword Keyword
2242 = TypeWithKeyword::getKeywordForTagTypeKind(TagKind);
2244 if (DependentTemplateName *DTN = Template.getAsDependentTemplateName()) {
2245 QualType T = Context.getDependentTemplateSpecializationType(Keyword,
2246 DTN->getQualifier(),
2247 DTN->getIdentifier(),
2250 // Build type-source information.
2252 DependentTemplateSpecializationTypeLoc SpecTL
2253 = TLB.push<DependentTemplateSpecializationTypeLoc>(T);
2254 SpecTL.setElaboratedKeywordLoc(TagLoc);
2255 SpecTL.setQualifierLoc(SS.getWithLocInContext(Context));
2256 SpecTL.setTemplateKeywordLoc(TemplateKWLoc);
2257 SpecTL.setTemplateNameLoc(TemplateLoc);
2258 SpecTL.setLAngleLoc(LAngleLoc);
2259 SpecTL.setRAngleLoc(RAngleLoc);
2260 for (unsigned I = 0, N = SpecTL.getNumArgs(); I != N; ++I)
2261 SpecTL.setArgLocInfo(I, TemplateArgs[I].getLocInfo());
2262 return CreateParsedType(T, TLB.getTypeSourceInfo(Context, T));
2265 if (TypeAliasTemplateDecl *TAT =
2266 dyn_cast_or_null<TypeAliasTemplateDecl>(Template.getAsTemplateDecl())) {
2267 // C++0x [dcl.type.elab]p2:
2268 // If the identifier resolves to a typedef-name or the simple-template-id
2269 // resolves to an alias template specialization, the
2270 // elaborated-type-specifier is ill-formed.
2271 Diag(TemplateLoc, diag::err_tag_reference_non_tag) << 4;
2272 Diag(TAT->getLocation(), diag::note_declared_at);
2275 QualType Result = CheckTemplateIdType(Template, TemplateLoc, TemplateArgs);
2276 if (Result.isNull())
2277 return TypeResult(true);
2279 // Check the tag kind
2280 if (const RecordType *RT = Result->getAs<RecordType>()) {
2281 RecordDecl *D = RT->getDecl();
2283 IdentifierInfo *Id = D->getIdentifier();
2284 assert(Id && "templated class must have an identifier");
2286 if (!isAcceptableTagRedeclaration(D, TagKind, TUK == TUK_Definition,
2288 Diag(TagLoc, diag::err_use_with_wrong_tag)
2290 << FixItHint::CreateReplacement(SourceRange(TagLoc), D->getKindName());
2291 Diag(D->getLocation(), diag::note_previous_use);
2295 // Provide source-location information for the template specialization.
2297 TemplateSpecializationTypeLoc SpecTL
2298 = TLB.push<TemplateSpecializationTypeLoc>(Result);
2299 SpecTL.setTemplateKeywordLoc(TemplateKWLoc);
2300 SpecTL.setTemplateNameLoc(TemplateLoc);
2301 SpecTL.setLAngleLoc(LAngleLoc);
2302 SpecTL.setRAngleLoc(RAngleLoc);
2303 for (unsigned i = 0, e = SpecTL.getNumArgs(); i != e; ++i)
2304 SpecTL.setArgLocInfo(i, TemplateArgs[i].getLocInfo());
2306 // Construct an elaborated type containing the nested-name-specifier (if any)
2308 Result = Context.getElaboratedType(Keyword, SS.getScopeRep(), Result);
2309 ElaboratedTypeLoc ElabTL = TLB.push<ElaboratedTypeLoc>(Result);
2310 ElabTL.setElaboratedKeywordLoc(TagLoc);
2311 ElabTL.setQualifierLoc(SS.getWithLocInContext(Context));
2312 return CreateParsedType(Result, TLB.getTypeSourceInfo(Context, Result));
2315 static bool CheckTemplatePartialSpecializationArgs(
2316 Sema &S, SourceLocation NameLoc, TemplateParameterList *TemplateParams,
2317 unsigned ExplicitArgs, SmallVectorImpl<TemplateArgument> &TemplateArgs);
2319 static bool CheckTemplateSpecializationScope(Sema &S, NamedDecl *Specialized,
2320 NamedDecl *PrevDecl,
2322 bool IsPartialSpecialization);
2324 static TemplateSpecializationKind getTemplateSpecializationKind(Decl *D);
2326 static bool isTemplateArgumentTemplateParameter(
2327 const TemplateArgument &Arg, unsigned Depth, unsigned Index) {
2328 switch (Arg.getKind()) {
2329 case TemplateArgument::Null:
2330 case TemplateArgument::NullPtr:
2331 case TemplateArgument::Integral:
2332 case TemplateArgument::Declaration:
2333 case TemplateArgument::Pack:
2334 case TemplateArgument::TemplateExpansion:
2337 case TemplateArgument::Type: {
2338 QualType Type = Arg.getAsType();
2339 const TemplateTypeParmType *TPT =
2340 Arg.getAsType()->getAs<TemplateTypeParmType>();
2341 return TPT && !Type.hasQualifiers() &&
2342 TPT->getDepth() == Depth && TPT->getIndex() == Index;
2345 case TemplateArgument::Expression: {
2346 DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Arg.getAsExpr());
2347 if (!DRE || !DRE->getDecl())
2349 const NonTypeTemplateParmDecl *NTTP =
2350 dyn_cast<NonTypeTemplateParmDecl>(DRE->getDecl());
2351 return NTTP && NTTP->getDepth() == Depth && NTTP->getIndex() == Index;
2354 case TemplateArgument::Template:
2355 const TemplateTemplateParmDecl *TTP =
2356 dyn_cast_or_null<TemplateTemplateParmDecl>(
2357 Arg.getAsTemplateOrTemplatePattern().getAsTemplateDecl());
2358 return TTP && TTP->getDepth() == Depth && TTP->getIndex() == Index;
2360 llvm_unreachable("unexpected kind of template argument");
2363 static bool isSameAsPrimaryTemplate(TemplateParameterList *Params,
2364 ArrayRef<TemplateArgument> Args) {
2365 if (Params->size() != Args.size())
2368 unsigned Depth = Params->getDepth();
2370 for (unsigned I = 0, N = Args.size(); I != N; ++I) {
2371 TemplateArgument Arg = Args[I];
2373 // If the parameter is a pack expansion, the argument must be a pack
2374 // whose only element is a pack expansion.
2375 if (Params->getParam(I)->isParameterPack()) {
2376 if (Arg.getKind() != TemplateArgument::Pack || Arg.pack_size() != 1 ||
2377 !Arg.pack_begin()->isPackExpansion())
2379 Arg = Arg.pack_begin()->getPackExpansionPattern();
2382 if (!isTemplateArgumentTemplateParameter(Arg, Depth, I))
2389 /// Convert the parser's template argument list representation into our form.
2390 static TemplateArgumentListInfo
2391 makeTemplateArgumentListInfo(Sema &S, TemplateIdAnnotation &TemplateId) {
2392 TemplateArgumentListInfo TemplateArgs(TemplateId.LAngleLoc,
2393 TemplateId.RAngleLoc);
2394 ASTTemplateArgsPtr TemplateArgsPtr(TemplateId.getTemplateArgs(),
2395 TemplateId.NumArgs);
2396 S.translateTemplateArguments(TemplateArgsPtr, TemplateArgs);
2397 return TemplateArgs;
2400 DeclResult Sema::ActOnVarTemplateSpecialization(
2401 Scope *S, Declarator &D, TypeSourceInfo *DI, SourceLocation TemplateKWLoc,
2402 TemplateParameterList *TemplateParams, StorageClass SC,
2403 bool IsPartialSpecialization) {
2404 // D must be variable template id.
2405 assert(D.getName().getKind() == UnqualifiedId::IK_TemplateId &&
2406 "Variable template specialization is declared with a template it.");
2408 TemplateIdAnnotation *TemplateId = D.getName().TemplateId;
2409 TemplateArgumentListInfo TemplateArgs =
2410 makeTemplateArgumentListInfo(*this, *TemplateId);
2411 SourceLocation TemplateNameLoc = D.getIdentifierLoc();
2412 SourceLocation LAngleLoc = TemplateId->LAngleLoc;
2413 SourceLocation RAngleLoc = TemplateId->RAngleLoc;
2415 TemplateName Name = TemplateId->Template.get();
2417 // The template-id must name a variable template.
2418 VarTemplateDecl *VarTemplate =
2419 dyn_cast_or_null<VarTemplateDecl>(Name.getAsTemplateDecl());
2421 NamedDecl *FnTemplate;
2422 if (auto *OTS = Name.getAsOverloadedTemplate())
2423 FnTemplate = *OTS->begin();
2425 FnTemplate = dyn_cast_or_null<FunctionTemplateDecl>(Name.getAsTemplateDecl());
2427 return Diag(D.getIdentifierLoc(), diag::err_var_spec_no_template_but_method)
2428 << FnTemplate->getDeclName();
2429 return Diag(D.getIdentifierLoc(), diag::err_var_spec_no_template)
2430 << IsPartialSpecialization;
2433 // Check for unexpanded parameter packs in any of the template arguments.
2434 for (unsigned I = 0, N = TemplateArgs.size(); I != N; ++I)
2435 if (DiagnoseUnexpandedParameterPack(TemplateArgs[I],
2436 UPPC_PartialSpecialization))
2439 // Check that the template argument list is well-formed for this
2441 SmallVector<TemplateArgument, 4> Converted;
2442 if (CheckTemplateArgumentList(VarTemplate, TemplateNameLoc, TemplateArgs,
2446 // Check that the type of this variable template specialization
2447 // matches the expected type.
2448 TypeSourceInfo *ExpectedDI;
2450 // Do substitution on the type of the declaration
2451 TemplateArgumentList TemplateArgList(TemplateArgumentList::OnStack,
2452 Converted.data(), Converted.size());
2453 InstantiatingTemplate Inst(*this, TemplateKWLoc, VarTemplate);
2454 if (Inst.isInvalid())
2456 VarDecl *Templated = VarTemplate->getTemplatedDecl();
2458 SubstType(Templated->getTypeSourceInfo(),
2459 MultiLevelTemplateArgumentList(TemplateArgList),
2460 Templated->getTypeSpecStartLoc(), Templated->getDeclName());
2465 // Find the variable template (partial) specialization declaration that
2466 // corresponds to these arguments.
2467 if (IsPartialSpecialization) {
2468 if (CheckTemplatePartialSpecializationArgs(
2469 *this, TemplateNameLoc, VarTemplate->getTemplateParameters(),
2470 TemplateArgs.size(), Converted))
2473 bool InstantiationDependent;
2474 if (!Name.isDependent() &&
2475 !TemplateSpecializationType::anyDependentTemplateArguments(
2476 TemplateArgs.getArgumentArray(), TemplateArgs.size(),
2477 InstantiationDependent)) {
2478 Diag(TemplateNameLoc, diag::err_partial_spec_fully_specialized)
2479 << VarTemplate->getDeclName();
2480 IsPartialSpecialization = false;
2483 if (isSameAsPrimaryTemplate(VarTemplate->getTemplateParameters(),
2485 // C++ [temp.class.spec]p9b3:
2487 // -- The argument list of the specialization shall not be identical
2488 // to the implicit argument list of the primary template.
2489 Diag(TemplateNameLoc, diag::err_partial_spec_args_match_primary_template)
2490 << /*variable template*/ 1
2491 << /*is definition*/(SC != SC_Extern && !CurContext->isRecord())
2492 << FixItHint::CreateRemoval(SourceRange(LAngleLoc, RAngleLoc));
2493 // FIXME: Recover from this by treating the declaration as a redeclaration
2494 // of the primary template.
2499 void *InsertPos = nullptr;
2500 VarTemplateSpecializationDecl *PrevDecl = nullptr;
2502 if (IsPartialSpecialization)
2503 // FIXME: Template parameter list matters too
2504 PrevDecl = VarTemplate->findPartialSpecialization(Converted, InsertPos);
2506 PrevDecl = VarTemplate->findSpecialization(Converted, InsertPos);
2508 VarTemplateSpecializationDecl *Specialization = nullptr;
2510 // Check whether we can declare a variable template specialization in
2511 // the current scope.
2512 if (CheckTemplateSpecializationScope(*this, VarTemplate, PrevDecl,
2514 IsPartialSpecialization))
2517 if (PrevDecl && PrevDecl->getSpecializationKind() == TSK_Undeclared) {
2518 // Since the only prior variable template specialization with these
2519 // arguments was referenced but not declared, reuse that
2520 // declaration node as our own, updating its source location and
2521 // the list of outer template parameters to reflect our new declaration.
2522 Specialization = PrevDecl;
2523 Specialization->setLocation(TemplateNameLoc);
2525 } else if (IsPartialSpecialization) {
2526 // Create a new class template partial specialization declaration node.
2527 VarTemplatePartialSpecializationDecl *PrevPartial =
2528 cast_or_null<VarTemplatePartialSpecializationDecl>(PrevDecl);
2529 VarTemplatePartialSpecializationDecl *Partial =
2530 VarTemplatePartialSpecializationDecl::Create(
2531 Context, VarTemplate->getDeclContext(), TemplateKWLoc,
2532 TemplateNameLoc, TemplateParams, VarTemplate, DI->getType(), DI, SC,
2533 Converted.data(), Converted.size(), TemplateArgs);
2536 VarTemplate->AddPartialSpecialization(Partial, InsertPos);
2537 Specialization = Partial;
2539 // If we are providing an explicit specialization of a member variable
2540 // template specialization, make a note of that.
2541 if (PrevPartial && PrevPartial->getInstantiatedFromMember())
2542 PrevPartial->setMemberSpecialization();
2544 // Check that all of the template parameters of the variable template
2545 // partial specialization are deducible from the template
2546 // arguments. If not, this variable template partial specialization
2547 // will never be used.
2548 llvm::SmallBitVector DeducibleParams(TemplateParams->size());
2549 MarkUsedTemplateParameters(Partial->getTemplateArgs(), true,
2550 TemplateParams->getDepth(), DeducibleParams);
2552 if (!DeducibleParams.all()) {
2553 unsigned NumNonDeducible =
2554 DeducibleParams.size() - DeducibleParams.count();
2555 Diag(TemplateNameLoc, diag::warn_partial_specs_not_deducible)
2556 << /*variable template*/ 1 << (NumNonDeducible > 1)
2557 << SourceRange(TemplateNameLoc, RAngleLoc);
2558 for (unsigned I = 0, N = DeducibleParams.size(); I != N; ++I) {
2559 if (!DeducibleParams[I]) {
2560 NamedDecl *Param = cast<NamedDecl>(TemplateParams->getParam(I));
2561 if (Param->getDeclName())
2562 Diag(Param->getLocation(), diag::note_partial_spec_unused_parameter)
2563 << Param->getDeclName();
2565 Diag(Param->getLocation(), diag::note_partial_spec_unused_parameter)
2571 // Create a new class template specialization declaration node for
2572 // this explicit specialization or friend declaration.
2573 Specialization = VarTemplateSpecializationDecl::Create(
2574 Context, VarTemplate->getDeclContext(), TemplateKWLoc, TemplateNameLoc,
2575 VarTemplate, DI->getType(), DI, SC, Converted.data(), Converted.size());
2576 Specialization->setTemplateArgsInfo(TemplateArgs);
2579 VarTemplate->AddSpecialization(Specialization, InsertPos);
2582 // C++ [temp.expl.spec]p6:
2583 // If a template, a member template or the member of a class template is
2584 // explicitly specialized then that specialization shall be declared
2585 // before the first use of that specialization that would cause an implicit
2586 // instantiation to take place, in every translation unit in which such a
2587 // use occurs; no diagnostic is required.
2588 if (PrevDecl && PrevDecl->getPointOfInstantiation().isValid()) {
2590 for (Decl *Prev = PrevDecl; Prev; Prev = Prev->getPreviousDecl()) {
2591 // Is there any previous explicit specialization declaration?
2592 if (getTemplateSpecializationKind(Prev) == TSK_ExplicitSpecialization) {
2599 SourceRange Range(TemplateNameLoc, RAngleLoc);
2600 Diag(TemplateNameLoc, diag::err_specialization_after_instantiation)
2603 Diag(PrevDecl->getPointOfInstantiation(),
2604 diag::note_instantiation_required_here)
2605 << (PrevDecl->getTemplateSpecializationKind() !=
2606 TSK_ImplicitInstantiation);
2611 Specialization->setTemplateKeywordLoc(TemplateKWLoc);
2612 Specialization->setLexicalDeclContext(CurContext);
2614 // Add the specialization into its lexical context, so that it can
2615 // be seen when iterating through the list of declarations in that
2616 // context. However, specializations are not found by name lookup.
2617 CurContext->addDecl(Specialization);
2619 // Note that this is an explicit specialization.
2620 Specialization->setSpecializationKind(TSK_ExplicitSpecialization);
2623 // Check that this isn't a redefinition of this specialization,
2624 // merging with previous declarations.
2625 LookupResult PrevSpec(*this, GetNameForDeclarator(D), LookupOrdinaryName,
2627 PrevSpec.addDecl(PrevDecl);
2628 D.setRedeclaration(CheckVariableDeclaration(Specialization, PrevSpec));
2629 } else if (Specialization->isStaticDataMember() &&
2630 Specialization->isOutOfLine()) {
2631 Specialization->setAccess(VarTemplate->getAccess());
2634 // Link instantiations of static data members back to the template from
2635 // which they were instantiated.
2636 if (Specialization->isStaticDataMember())
2637 Specialization->setInstantiationOfStaticDataMember(
2638 VarTemplate->getTemplatedDecl(),
2639 Specialization->getSpecializationKind());
2641 return Specialization;
2645 /// \brief A partial specialization whose template arguments have matched
2646 /// a given template-id.
2647 struct PartialSpecMatchResult {
2648 VarTemplatePartialSpecializationDecl *Partial;
2649 TemplateArgumentList *Args;
2654 Sema::CheckVarTemplateId(VarTemplateDecl *Template, SourceLocation TemplateLoc,
2655 SourceLocation TemplateNameLoc,
2656 const TemplateArgumentListInfo &TemplateArgs) {
2657 assert(Template && "A variable template id without template?");
2659 // Check that the template argument list is well-formed for this template.
2660 SmallVector<TemplateArgument, 4> Converted;
2661 if (CheckTemplateArgumentList(
2662 Template, TemplateNameLoc,
2663 const_cast<TemplateArgumentListInfo &>(TemplateArgs), false,
2667 // Find the variable template specialization declaration that
2668 // corresponds to these arguments.
2669 void *InsertPos = nullptr;
2670 if (VarTemplateSpecializationDecl *Spec = Template->findSpecialization(
2671 Converted, InsertPos))
2672 // If we already have a variable template specialization, return it.
2675 // This is the first time we have referenced this variable template
2676 // specialization. Create the canonical declaration and add it to
2677 // the set of specializations, based on the closest partial specialization
2678 // that it represents. That is,
2679 VarDecl *InstantiationPattern = Template->getTemplatedDecl();
2680 TemplateArgumentList TemplateArgList(TemplateArgumentList::OnStack,
2681 Converted.data(), Converted.size());
2682 TemplateArgumentList *InstantiationArgs = &TemplateArgList;
2683 bool AmbiguousPartialSpec = false;
2684 typedef PartialSpecMatchResult MatchResult;
2685 SmallVector<MatchResult, 4> Matched;
2686 SourceLocation PointOfInstantiation = TemplateNameLoc;
2687 TemplateSpecCandidateSet FailedCandidates(PointOfInstantiation);
2689 // 1. Attempt to find the closest partial specialization that this
2690 // specializes, if any.
2691 // If any of the template arguments is dependent, then this is probably
2692 // a placeholder for an incomplete declarative context; which must be
2693 // complete by instantiation time. Thus, do not search through the partial
2694 // specializations yet.
2695 // TODO: Unify with InstantiateClassTemplateSpecialization()?
2696 // Perhaps better after unification of DeduceTemplateArguments() and
2697 // getMoreSpecializedPartialSpecialization().
2698 bool InstantiationDependent = false;
2699 if (!TemplateSpecializationType::anyDependentTemplateArguments(
2700 TemplateArgs, InstantiationDependent)) {
2702 SmallVector<VarTemplatePartialSpecializationDecl *, 4> PartialSpecs;
2703 Template->getPartialSpecializations(PartialSpecs);
2705 for (unsigned I = 0, N = PartialSpecs.size(); I != N; ++I) {
2706 VarTemplatePartialSpecializationDecl *Partial = PartialSpecs[I];
2707 TemplateDeductionInfo Info(FailedCandidates.getLocation());
2709 if (TemplateDeductionResult Result =
2710 DeduceTemplateArguments(Partial, TemplateArgList, Info)) {
2711 // Store the failed-deduction information for use in diagnostics, later.
2712 // TODO: Actually use the failed-deduction info?
2713 FailedCandidates.addCandidate()
2714 .set(Partial, MakeDeductionFailureInfo(Context, Result, Info));
2717 Matched.push_back(PartialSpecMatchResult());
2718 Matched.back().Partial = Partial;
2719 Matched.back().Args = Info.take();
2723 if (Matched.size() >= 1) {
2724 SmallVector<MatchResult, 4>::iterator Best = Matched.begin();
2725 if (Matched.size() == 1) {
2726 // -- If exactly one matching specialization is found, the
2727 // instantiation is generated from that specialization.
2728 // We don't need to do anything for this.
2730 // -- If more than one matching specialization is found, the
2731 // partial order rules (14.5.4.2) are used to determine
2732 // whether one of the specializations is more specialized
2733 // than the others. If none of the specializations is more
2734 // specialized than all of the other matching
2735 // specializations, then the use of the variable template is
2736 // ambiguous and the program is ill-formed.
2737 for (SmallVector<MatchResult, 4>::iterator P = Best + 1,
2738 PEnd = Matched.end();
2740 if (getMoreSpecializedPartialSpecialization(P->Partial, Best->Partial,
2741 PointOfInstantiation) ==
2746 // Determine if the best partial specialization is more specialized than
2748 for (SmallVector<MatchResult, 4>::iterator P = Matched.begin(),
2749 PEnd = Matched.end();
2751 if (P != Best && getMoreSpecializedPartialSpecialization(
2752 P->Partial, Best->Partial,
2753 PointOfInstantiation) != Best->Partial) {
2754 AmbiguousPartialSpec = true;
2760 // Instantiate using the best variable template partial specialization.
2761 InstantiationPattern = Best->Partial;
2762 InstantiationArgs = Best->Args;
2764 // -- If no match is found, the instantiation is generated
2765 // from the primary template.
2766 // InstantiationPattern = Template->getTemplatedDecl();
2770 // 2. Create the canonical declaration.
2771 // Note that we do not instantiate the variable just yet, since
2772 // instantiation is handled in DoMarkVarDeclReferenced().
2773 // FIXME: LateAttrs et al.?
2774 VarTemplateSpecializationDecl *Decl = BuildVarTemplateInstantiation(
2775 Template, InstantiationPattern, *InstantiationArgs, TemplateArgs,
2776 Converted, TemplateNameLoc, InsertPos /*, LateAttrs, StartingScope*/);
2780 if (AmbiguousPartialSpec) {
2781 // Partial ordering did not produce a clear winner. Complain.
2782 Decl->setInvalidDecl();
2783 Diag(PointOfInstantiation, diag::err_partial_spec_ordering_ambiguous)
2786 // Print the matching partial specializations.
2787 for (SmallVector<MatchResult, 4>::iterator P = Matched.begin(),
2788 PEnd = Matched.end();
2790 Diag(P->Partial->getLocation(), diag::note_partial_spec_match)
2791 << getTemplateArgumentBindingsText(
2792 P->Partial->getTemplateParameters(), *P->Args);
2796 if (VarTemplatePartialSpecializationDecl *D =
2797 dyn_cast<VarTemplatePartialSpecializationDecl>(InstantiationPattern))
2798 Decl->setInstantiationOf(D, InstantiationArgs);
2800 assert(Decl && "No variable template specialization?");
2805 Sema::CheckVarTemplateId(const CXXScopeSpec &SS,
2806 const DeclarationNameInfo &NameInfo,
2807 VarTemplateDecl *Template, SourceLocation TemplateLoc,
2808 const TemplateArgumentListInfo *TemplateArgs) {
2810 DeclResult Decl = CheckVarTemplateId(Template, TemplateLoc, NameInfo.getLoc(),
2812 if (Decl.isInvalid())
2815 VarDecl *Var = cast<VarDecl>(Decl.get());
2816 if (!Var->getTemplateSpecializationKind())
2817 Var->setTemplateSpecializationKind(TSK_ImplicitInstantiation,
2820 // Build an ordinary singleton decl ref.
2821 return BuildDeclarationNameExpr(SS, NameInfo, Var,
2822 /*FoundD=*/nullptr, TemplateArgs);
2825 ExprResult Sema::BuildTemplateIdExpr(const CXXScopeSpec &SS,
2826 SourceLocation TemplateKWLoc,
2829 const TemplateArgumentListInfo *TemplateArgs) {
2830 // FIXME: Can we do any checking at this point? I guess we could check the
2831 // template arguments that we have against the template name, if the template
2832 // name refers to a single template. That's not a terribly common case,
2834 // foo<int> could identify a single function unambiguously
2835 // This approach does NOT work, since f<int>(1);
2836 // gets resolved prior to resorting to overload resolution
2837 // i.e., template<class T> void f(double);
2838 // vs template<class T, class U> void f(U);
2840 // These should be filtered out by our callers.
2841 assert(!R.empty() && "empty lookup results when building templateid");
2842 assert(!R.isAmbiguous() && "ambiguous lookup when building templateid");
2844 // In C++1y, check variable template ids.
2845 bool InstantiationDependent;
2846 if (R.getAsSingle<VarTemplateDecl>() &&
2847 !TemplateSpecializationType::anyDependentTemplateArguments(
2848 *TemplateArgs, InstantiationDependent)) {
2849 return CheckVarTemplateId(SS, R.getLookupNameInfo(),
2850 R.getAsSingle<VarTemplateDecl>(),
2851 TemplateKWLoc, TemplateArgs);
2854 // We don't want lookup warnings at this point.
2855 R.suppressDiagnostics();
2857 UnresolvedLookupExpr *ULE
2858 = UnresolvedLookupExpr::Create(Context, R.getNamingClass(),
2859 SS.getWithLocInContext(Context),
2861 R.getLookupNameInfo(),
2862 RequiresADL, TemplateArgs,
2863 R.begin(), R.end());
2868 // We actually only call this from template instantiation.
2870 Sema::BuildQualifiedTemplateIdExpr(CXXScopeSpec &SS,
2871 SourceLocation TemplateKWLoc,
2872 const DeclarationNameInfo &NameInfo,
2873 const TemplateArgumentListInfo *TemplateArgs) {
2875 assert(TemplateArgs || TemplateKWLoc.isValid());
2877 if (!(DC = computeDeclContext(SS, false)) ||
2878 DC->isDependentContext() ||
2879 RequireCompleteDeclContext(SS, DC))
2882 bool MemberOfUnknownSpecialization;
2883 LookupResult R(*this, NameInfo, LookupOrdinaryName);
2884 LookupTemplateName(R, (Scope*)nullptr, SS, QualType(), /*Entering*/ false,
2885 MemberOfUnknownSpecialization);
2887 if (R.isAmbiguous())
2891 Diag(NameInfo.getLoc(), diag::err_template_kw_refers_to_non_template)
2892 << NameInfo.getName() << SS.getRange();
2896 if (ClassTemplateDecl *Temp = R.getAsSingle<ClassTemplateDecl>()) {
2897 Diag(NameInfo.getLoc(), diag::err_template_kw_refers_to_class_template)
2899 << NameInfo.getName().getAsString() << SS.getRange();
2900 Diag(Temp->getLocation(), diag::note_referenced_class_template);
2904 return BuildTemplateIdExpr(SS, TemplateKWLoc, R, /*ADL*/ false, TemplateArgs);
2907 /// \brief Form a dependent template name.
2909 /// This action forms a dependent template name given the template
2910 /// name and its (presumably dependent) scope specifier. For
2911 /// example, given "MetaFun::template apply", the scope specifier \p
2912 /// SS will be "MetaFun::", \p TemplateKWLoc contains the location
2913 /// of the "template" keyword, and "apply" is the \p Name.
2914 TemplateNameKind Sema::ActOnDependentTemplateName(Scope *S,
2916 SourceLocation TemplateKWLoc,
2917 UnqualifiedId &Name,
2918 ParsedType ObjectType,
2919 bool EnteringContext,
2920 TemplateTy &Result) {
2921 if (TemplateKWLoc.isValid() && S && !S->getTemplateParamParent())
2923 getLangOpts().CPlusPlus11 ?
2924 diag::warn_cxx98_compat_template_outside_of_template :
2925 diag::ext_template_outside_of_template)
2926 << FixItHint::CreateRemoval(TemplateKWLoc);
2928 DeclContext *LookupCtx = nullptr;
2930 LookupCtx = computeDeclContext(SS, EnteringContext);
2931 if (!LookupCtx && ObjectType)
2932 LookupCtx = computeDeclContext(ObjectType.get());
2934 // C++0x [temp.names]p5:
2935 // If a name prefixed by the keyword template is not the name of
2936 // a template, the program is ill-formed. [Note: the keyword
2937 // template may not be applied to non-template members of class
2938 // templates. -end note ] [ Note: as is the case with the
2939 // typename prefix, the template prefix is allowed in cases
2940 // where it is not strictly necessary; i.e., when the
2941 // nested-name-specifier or the expression on the left of the ->
2942 // or . is not dependent on a template-parameter, or the use
2943 // does not appear in the scope of a template. -end note]
2945 // Note: C++03 was more strict here, because it banned the use of
2946 // the "template" keyword prior to a template-name that was not a
2947 // dependent name. C++ DR468 relaxed this requirement (the
2948 // "template" keyword is now permitted). We follow the C++0x
2949 // rules, even in C++03 mode with a warning, retroactively applying the DR.
2950 bool MemberOfUnknownSpecialization;
2951 TemplateNameKind TNK = isTemplateName(S, SS, TemplateKWLoc.isValid(), Name,
2952 ObjectType, EnteringContext, Result,
2953 MemberOfUnknownSpecialization);
2954 if (TNK == TNK_Non_template && LookupCtx->isDependentContext() &&
2955 isa<CXXRecordDecl>(LookupCtx) &&
2956 (!cast<CXXRecordDecl>(LookupCtx)->hasDefinition() ||
2957 cast<CXXRecordDecl>(LookupCtx)->hasAnyDependentBases())) {
2958 // This is a dependent template. Handle it below.
2959 } else if (TNK == TNK_Non_template) {
2960 Diag(Name.getLocStart(),
2961 diag::err_template_kw_refers_to_non_template)
2962 << GetNameFromUnqualifiedId(Name).getName()
2963 << Name.getSourceRange()
2965 return TNK_Non_template;
2967 // We found something; return it.
2972 NestedNameSpecifier *Qualifier = SS.getScopeRep();
2974 switch (Name.getKind()) {
2975 case UnqualifiedId::IK_Identifier:
2976 Result = TemplateTy::make(Context.getDependentTemplateName(Qualifier,
2978 return TNK_Dependent_template_name;
2980 case UnqualifiedId::IK_OperatorFunctionId:
2981 Result = TemplateTy::make(Context.getDependentTemplateName(Qualifier,
2982 Name.OperatorFunctionId.Operator));
2983 return TNK_Function_template;
2985 case UnqualifiedId::IK_LiteralOperatorId:
2986 llvm_unreachable("literal operator id cannot have a dependent scope");
2992 Diag(Name.getLocStart(),
2993 diag::err_template_kw_refers_to_non_template)
2994 << GetNameFromUnqualifiedId(Name).getName()
2995 << Name.getSourceRange()
2997 return TNK_Non_template;
3000 bool Sema::CheckTemplateTypeArgument(TemplateTypeParmDecl *Param,
3001 TemplateArgumentLoc &AL,
3002 SmallVectorImpl<TemplateArgument> &Converted) {
3003 const TemplateArgument &Arg = AL.getArgument();
3005 TypeSourceInfo *TSI = nullptr;
3007 // Check template type parameter.
3008 switch(Arg.getKind()) {
3009 case TemplateArgument::Type:
3010 // C++ [temp.arg.type]p1:
3011 // A template-argument for a template-parameter which is a
3012 // type shall be a type-id.
3013 ArgType = Arg.getAsType();
3014 TSI = AL.getTypeSourceInfo();
3016 case TemplateArgument::Template: {
3017 // We have a template type parameter but the template argument
3018 // is a template without any arguments.
3019 SourceRange SR = AL.getSourceRange();
3020 TemplateName Name = Arg.getAsTemplate();
3021 Diag(SR.getBegin(), diag::err_template_missing_args)
3023 if (TemplateDecl *Decl = Name.getAsTemplateDecl())
3024 Diag(Decl->getLocation(), diag::note_template_decl_here);
3028 case TemplateArgument::Expression: {
3029 // We have a template type parameter but the template argument is an
3030 // expression; see if maybe it is missing the "typename" keyword.
3032 DeclarationNameInfo NameInfo;
3034 if (DeclRefExpr *ArgExpr = dyn_cast<DeclRefExpr>(Arg.getAsExpr())) {
3035 SS.Adopt(ArgExpr->getQualifierLoc());
3036 NameInfo = ArgExpr->getNameInfo();
3037 } else if (DependentScopeDeclRefExpr *ArgExpr =
3038 dyn_cast<DependentScopeDeclRefExpr>(Arg.getAsExpr())) {
3039 SS.Adopt(ArgExpr->getQualifierLoc());
3040 NameInfo = ArgExpr->getNameInfo();
3041 } else if (CXXDependentScopeMemberExpr *ArgExpr =
3042 dyn_cast<CXXDependentScopeMemberExpr>(Arg.getAsExpr())) {
3043 if (ArgExpr->isImplicitAccess()) {
3044 SS.Adopt(ArgExpr->getQualifierLoc());
3045 NameInfo = ArgExpr->getMemberNameInfo();
3049 if (auto *II = NameInfo.getName().getAsIdentifierInfo()) {
3050 LookupResult Result(*this, NameInfo, LookupOrdinaryName);
3051 LookupParsedName(Result, CurScope, &SS);
3053 if (Result.getAsSingle<TypeDecl>() ||
3054 Result.getResultKind() ==
3055 LookupResult::NotFoundInCurrentInstantiation) {
3056 // Suggest that the user add 'typename' before the NNS.
3057 SourceLocation Loc = AL.getSourceRange().getBegin();
3058 Diag(Loc, getLangOpts().MSVCCompat
3059 ? diag::ext_ms_template_type_arg_missing_typename
3060 : diag::err_template_arg_must_be_type_suggest)
3061 << FixItHint::CreateInsertion(Loc, "typename ");
3062 Diag(Param->getLocation(), diag::note_template_param_here);
3064 // Recover by synthesizing a type using the location information that we
3067 Context.getDependentNameType(ETK_Typename, SS.getScopeRep(), II);
3069 DependentNameTypeLoc TL = TLB.push<DependentNameTypeLoc>(ArgType);
3070 TL.setElaboratedKeywordLoc(SourceLocation(/*synthesized*/));
3071 TL.setQualifierLoc(SS.getWithLocInContext(Context));
3072 TL.setNameLoc(NameInfo.getLoc());
3073 TSI = TLB.getTypeSourceInfo(Context, ArgType);
3075 // Overwrite our input TemplateArgumentLoc so that we can recover
3077 AL = TemplateArgumentLoc(TemplateArgument(ArgType),
3078 TemplateArgumentLocInfo(TSI));
3086 // We have a template type parameter but the template argument
3088 SourceRange SR = AL.getSourceRange();
3089 Diag(SR.getBegin(), diag::err_template_arg_must_be_type) << SR;
3090 Diag(Param->getLocation(), diag::note_template_param_here);
3096 if (CheckTemplateArgument(Param, TSI))
3099 // Add the converted template type argument.
3100 ArgType = Context.getCanonicalType(ArgType);
3103 // If an explicitly-specified template argument type is a lifetime type
3104 // with no lifetime qualifier, the __strong lifetime qualifier is inferred.
3105 if (getLangOpts().ObjCAutoRefCount &&
3106 ArgType->isObjCLifetimeType() &&
3107 !ArgType.getObjCLifetime()) {
3109 Qs.setObjCLifetime(Qualifiers::OCL_Strong);
3110 ArgType = Context.getQualifiedType(ArgType, Qs);
3113 Converted.push_back(TemplateArgument(ArgType));
3117 /// \brief Substitute template arguments into the default template argument for
3118 /// the given template type parameter.
3120 /// \param SemaRef the semantic analysis object for which we are performing
3121 /// the substitution.
3123 /// \param Template the template that we are synthesizing template arguments
3126 /// \param TemplateLoc the location of the template name that started the
3127 /// template-id we are checking.
3129 /// \param RAngleLoc the location of the right angle bracket ('>') that
3130 /// terminates the template-id.
3132 /// \param Param the template template parameter whose default we are
3133 /// substituting into.
3135 /// \param Converted the list of template arguments provided for template
3136 /// parameters that precede \p Param in the template parameter list.
3137 /// \returns the substituted template argument, or NULL if an error occurred.
3138 static TypeSourceInfo *
3139 SubstDefaultTemplateArgument(Sema &SemaRef,
3140 TemplateDecl *Template,
3141 SourceLocation TemplateLoc,
3142 SourceLocation RAngleLoc,
3143 TemplateTypeParmDecl *Param,
3144 SmallVectorImpl<TemplateArgument> &Converted) {
3145 TypeSourceInfo *ArgType = Param->getDefaultArgumentInfo();
3147 // If the argument type is dependent, instantiate it now based
3148 // on the previously-computed template arguments.
3149 if (ArgType->getType()->isDependentType()) {
3150 Sema::InstantiatingTemplate Inst(SemaRef, TemplateLoc,
3151 Template, Converted,
3152 SourceRange(TemplateLoc, RAngleLoc));
3153 if (Inst.isInvalid())
3156 TemplateArgumentList TemplateArgs(TemplateArgumentList::OnStack,
3157 Converted.data(), Converted.size());
3159 // Only substitute for the innermost template argument list.
3160 MultiLevelTemplateArgumentList TemplateArgLists;
3161 TemplateArgLists.addOuterTemplateArguments(&TemplateArgs);
3162 for (unsigned i = 0, e = Param->getDepth(); i != e; ++i)
3163 TemplateArgLists.addOuterTemplateArguments(None);
3165 Sema::ContextRAII SavedContext(SemaRef, Template->getDeclContext());
3167 SemaRef.SubstType(ArgType, TemplateArgLists,
3168 Param->getDefaultArgumentLoc(), Param->getDeclName());
3174 /// \brief Substitute template arguments into the default template argument for
3175 /// the given non-type template parameter.
3177 /// \param SemaRef the semantic analysis object for which we are performing
3178 /// the substitution.
3180 /// \param Template the template that we are synthesizing template arguments
3183 /// \param TemplateLoc the location of the template name that started the
3184 /// template-id we are checking.
3186 /// \param RAngleLoc the location of the right angle bracket ('>') that
3187 /// terminates the template-id.
3189 /// \param Param the non-type template parameter whose default we are
3190 /// substituting into.
3192 /// \param Converted the list of template arguments provided for template
3193 /// parameters that precede \p Param in the template parameter list.
3195 /// \returns the substituted template argument, or NULL if an error occurred.
3197 SubstDefaultTemplateArgument(Sema &SemaRef,
3198 TemplateDecl *Template,
3199 SourceLocation TemplateLoc,
3200 SourceLocation RAngleLoc,
3201 NonTypeTemplateParmDecl *Param,
3202 SmallVectorImpl<TemplateArgument> &Converted) {
3203 Sema::InstantiatingTemplate Inst(SemaRef, TemplateLoc,
3204 Template, Converted,
3205 SourceRange(TemplateLoc, RAngleLoc));
3206 if (Inst.isInvalid())
3209 TemplateArgumentList TemplateArgs(TemplateArgumentList::OnStack,
3210 Converted.data(), Converted.size());
3212 // Only substitute for the innermost template argument list.
3213 MultiLevelTemplateArgumentList TemplateArgLists;
3214 TemplateArgLists.addOuterTemplateArguments(&TemplateArgs);
3215 for (unsigned i = 0, e = Param->getDepth(); i != e; ++i)
3216 TemplateArgLists.addOuterTemplateArguments(None);
3218 Sema::ContextRAII SavedContext(SemaRef, Template->getDeclContext());
3219 EnterExpressionEvaluationContext Unevaluated(SemaRef, Sema::Unevaluated);
3220 return SemaRef.SubstExpr(Param->getDefaultArgument(), TemplateArgLists);
3223 /// \brief Substitute template arguments into the default template argument for
3224 /// the given template template parameter.
3226 /// \param SemaRef the semantic analysis object for which we are performing
3227 /// the substitution.
3229 /// \param Template the template that we are synthesizing template arguments
3232 /// \param TemplateLoc the location of the template name that started the
3233 /// template-id we are checking.
3235 /// \param RAngleLoc the location of the right angle bracket ('>') that
3236 /// terminates the template-id.
3238 /// \param Param the template template parameter whose default we are
3239 /// substituting into.
3241 /// \param Converted the list of template arguments provided for template
3242 /// parameters that precede \p Param in the template parameter list.
3244 /// \param QualifierLoc Will be set to the nested-name-specifier (with
3245 /// source-location information) that precedes the template name.
3247 /// \returns the substituted template argument, or NULL if an error occurred.
3249 SubstDefaultTemplateArgument(Sema &SemaRef,
3250 TemplateDecl *Template,
3251 SourceLocation TemplateLoc,
3252 SourceLocation RAngleLoc,
3253 TemplateTemplateParmDecl *Param,
3254 SmallVectorImpl<TemplateArgument> &Converted,
3255 NestedNameSpecifierLoc &QualifierLoc) {
3256 Sema::InstantiatingTemplate Inst(SemaRef, TemplateLoc, Template, Converted,
3257 SourceRange(TemplateLoc, RAngleLoc));
3258 if (Inst.isInvalid())
3259 return TemplateName();
3261 TemplateArgumentList TemplateArgs(TemplateArgumentList::OnStack,
3262 Converted.data(), Converted.size());
3264 // Only substitute for the innermost template argument list.
3265 MultiLevelTemplateArgumentList TemplateArgLists;
3266 TemplateArgLists.addOuterTemplateArguments(&TemplateArgs);
3267 for (unsigned i = 0, e = Param->getDepth(); i != e; ++i)
3268 TemplateArgLists.addOuterTemplateArguments(None);
3270 Sema::ContextRAII SavedContext(SemaRef, Template->getDeclContext());
3271 // Substitute into the nested-name-specifier first,
3272 QualifierLoc = Param->getDefaultArgument().getTemplateQualifierLoc();
3275 SemaRef.SubstNestedNameSpecifierLoc(QualifierLoc, TemplateArgLists);
3277 return TemplateName();
3280 return SemaRef.SubstTemplateName(
3282 Param->getDefaultArgument().getArgument().getAsTemplate(),
3283 Param->getDefaultArgument().getTemplateNameLoc(),
3287 /// \brief If the given template parameter has a default template
3288 /// argument, substitute into that default template argument and
3289 /// return the corresponding template argument.
3291 Sema::SubstDefaultTemplateArgumentIfAvailable(TemplateDecl *Template,
3292 SourceLocation TemplateLoc,
3293 SourceLocation RAngleLoc,
3295 SmallVectorImpl<TemplateArgument>
3297 bool &HasDefaultArg) {
3298 HasDefaultArg = false;
3300 if (TemplateTypeParmDecl *TypeParm = dyn_cast<TemplateTypeParmDecl>(Param)) {
3301 if (!TypeParm->hasDefaultArgument())
3302 return TemplateArgumentLoc();
3304 HasDefaultArg = true;
3305 TypeSourceInfo *DI = SubstDefaultTemplateArgument(*this, Template,
3311 return TemplateArgumentLoc(TemplateArgument(DI->getType()), DI);
3313 return TemplateArgumentLoc();
3316 if (NonTypeTemplateParmDecl *NonTypeParm
3317 = dyn_cast<NonTypeTemplateParmDecl>(Param)) {
3318 if (!NonTypeParm->hasDefaultArgument())
3319 return TemplateArgumentLoc();
3321 HasDefaultArg = true;
3322 ExprResult Arg = SubstDefaultTemplateArgument(*this, Template,
3327 if (Arg.isInvalid())
3328 return TemplateArgumentLoc();
3330 Expr *ArgE = Arg.getAs<Expr>();
3331 return TemplateArgumentLoc(TemplateArgument(ArgE), ArgE);
3334 TemplateTemplateParmDecl *TempTempParm
3335 = cast<TemplateTemplateParmDecl>(Param);
3336 if (!TempTempParm->hasDefaultArgument())
3337 return TemplateArgumentLoc();
3339 HasDefaultArg = true;
3340 NestedNameSpecifierLoc QualifierLoc;
3341 TemplateName TName = SubstDefaultTemplateArgument(*this, Template,
3348 return TemplateArgumentLoc();
3350 return TemplateArgumentLoc(TemplateArgument(TName),
3351 TempTempParm->getDefaultArgument().getTemplateQualifierLoc(),
3352 TempTempParm->getDefaultArgument().getTemplateNameLoc());
3355 /// \brief Check that the given template argument corresponds to the given
3356 /// template parameter.
3358 /// \param Param The template parameter against which the argument will be
3361 /// \param Arg The template argument.
3363 /// \param Template The template in which the template argument resides.
3365 /// \param TemplateLoc The location of the template name for the template
3366 /// whose argument list we're matching.
3368 /// \param RAngleLoc The location of the right angle bracket ('>') that closes
3369 /// the template argument list.
3371 /// \param ArgumentPackIndex The index into the argument pack where this
3372 /// argument will be placed. Only valid if the parameter is a parameter pack.
3374 /// \param Converted The checked, converted argument will be added to the
3375 /// end of this small vector.
3377 /// \param CTAK Describes how we arrived at this particular template argument:
3378 /// explicitly written, deduced, etc.
3380 /// \returns true on error, false otherwise.
3381 bool Sema::CheckTemplateArgument(NamedDecl *Param,
3382 TemplateArgumentLoc &Arg,
3383 NamedDecl *Template,
3384 SourceLocation TemplateLoc,
3385 SourceLocation RAngleLoc,
3386 unsigned ArgumentPackIndex,
3387 SmallVectorImpl<TemplateArgument> &Converted,
3388 CheckTemplateArgumentKind CTAK) {
3389 // Check template type parameters.
3390 if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(Param))
3391 return CheckTemplateTypeArgument(TTP, Arg, Converted);
3393 // Check non-type template parameters.
3394 if (NonTypeTemplateParmDecl *NTTP =dyn_cast<NonTypeTemplateParmDecl>(Param)) {
3395 // Do substitution on the type of the non-type template parameter
3396 // with the template arguments we've seen thus far. But if the
3397 // template has a dependent context then we cannot substitute yet.
3398 QualType NTTPType = NTTP->getType();
3399 if (NTTP->isParameterPack() && NTTP->isExpandedParameterPack())
3400 NTTPType = NTTP->getExpansionType(ArgumentPackIndex);
3402 if (NTTPType->isDependentType() &&
3403 !isa<TemplateTemplateParmDecl>(Template) &&
3404 !Template->getDeclContext()->isDependentContext()) {
3405 // Do substitution on the type of the non-type template parameter.
3406 InstantiatingTemplate Inst(*this, TemplateLoc, Template,
3408 SourceRange(TemplateLoc, RAngleLoc));
3409 if (Inst.isInvalid())
3412 TemplateArgumentList TemplateArgs(TemplateArgumentList::OnStack,
3413 Converted.data(), Converted.size());
3414 NTTPType = SubstType(NTTPType,
3415 MultiLevelTemplateArgumentList(TemplateArgs),
3416 NTTP->getLocation(),
3417 NTTP->getDeclName());
3418 // If that worked, check the non-type template parameter type
3420 if (!NTTPType.isNull())
3421 NTTPType = CheckNonTypeTemplateParameterType(NTTPType,
3422 NTTP->getLocation());
3423 if (NTTPType.isNull())
3427 switch (Arg.getArgument().getKind()) {
3428 case TemplateArgument::Null:
3429 llvm_unreachable("Should never see a NULL template argument here");
3431 case TemplateArgument::Expression: {
3432 TemplateArgument Result;
3434 CheckTemplateArgument(NTTP, NTTPType, Arg.getArgument().getAsExpr(),
3436 if (Res.isInvalid())
3439 Converted.push_back(Result);
3443 case TemplateArgument::Declaration:
3444 case TemplateArgument::Integral:
3445 case TemplateArgument::NullPtr:
3446 // We've already checked this template argument, so just copy
3447 // it to the list of converted arguments.
3448 Converted.push_back(Arg.getArgument());
3451 case TemplateArgument::Template:
3452 case TemplateArgument::TemplateExpansion:
3453 // We were given a template template argument. It may not be ill-formed;
3455 if (DependentTemplateName *DTN
3456 = Arg.getArgument().getAsTemplateOrTemplatePattern()
3457 .getAsDependentTemplateName()) {
3458 // We have a template argument such as \c T::template X, which we
3459 // parsed as a template template argument. However, since we now
3460 // know that we need a non-type template argument, convert this
3461 // template name into an expression.
3463 DeclarationNameInfo NameInfo(DTN->getIdentifier(),
3464 Arg.getTemplateNameLoc());
3467 SS.Adopt(Arg.getTemplateQualifierLoc());
3468 // FIXME: the template-template arg was a DependentTemplateName,
3469 // so it was provided with a template keyword. However, its source
3470 // location is not stored in the template argument structure.
3471 SourceLocation TemplateKWLoc;
3472 ExprResult E = DependentScopeDeclRefExpr::Create(
3473 Context, SS.getWithLocInContext(Context), TemplateKWLoc, NameInfo,
3476 // If we parsed the template argument as a pack expansion, create a
3477 // pack expansion expression.
3478 if (Arg.getArgument().getKind() == TemplateArgument::TemplateExpansion){
3479 E = ActOnPackExpansion(E.get(), Arg.getTemplateEllipsisLoc());
3484 TemplateArgument Result;
3485 E = CheckTemplateArgument(NTTP, NTTPType, E.get(), Result);
3489 Converted.push_back(Result);
3493 // We have a template argument that actually does refer to a class
3494 // template, alias template, or template template parameter, and
3495 // therefore cannot be a non-type template argument.
3496 Diag(Arg.getLocation(), diag::err_template_arg_must_be_expr)
3497 << Arg.getSourceRange();
3499 Diag(Param->getLocation(), diag::note_template_param_here);
3502 case TemplateArgument::Type: {
3503 // We have a non-type template parameter but the template
3504 // argument is a type.
3506 // C++ [temp.arg]p2:
3507 // In a template-argument, an ambiguity between a type-id and
3508 // an expression is resolved to a type-id, regardless of the
3509 // form of the corresponding template-parameter.
3511 // We warn specifically about this case, since it can be rather
3512 // confusing for users.
3513 QualType T = Arg.getArgument().getAsType();
3514 SourceRange SR = Arg.getSourceRange();
3515 if (T->isFunctionType())
3516 Diag(SR.getBegin(), diag::err_template_arg_nontype_ambig) << SR << T;
3518 Diag(SR.getBegin(), diag::err_template_arg_must_be_expr) << SR;
3519 Diag(Param->getLocation(), diag::note_template_param_here);
3523 case TemplateArgument::Pack:
3524 llvm_unreachable("Caller must expand template argument packs");
3531 // Check template template parameters.
3532 TemplateTemplateParmDecl *TempParm = cast<TemplateTemplateParmDecl>(Param);
3534 // Substitute into the template parameter list of the template
3535 // template parameter, since previously-supplied template arguments
3536 // may appear within the template template parameter.
3538 // Set up a template instantiation context.
3539 LocalInstantiationScope Scope(*this);
3540 InstantiatingTemplate Inst(*this, TemplateLoc, Template,
3541 TempParm, Converted,
3542 SourceRange(TemplateLoc, RAngleLoc));
3543 if (Inst.isInvalid())
3546 TemplateArgumentList TemplateArgs(TemplateArgumentList::OnStack,
3547 Converted.data(), Converted.size());
3548 TempParm = cast_or_null<TemplateTemplateParmDecl>(
3549 SubstDecl(TempParm, CurContext,
3550 MultiLevelTemplateArgumentList(TemplateArgs)));
3555 switch (Arg.getArgument().getKind()) {
3556 case TemplateArgument::Null:
3557 llvm_unreachable("Should never see a NULL template argument here");
3559 case TemplateArgument::Template:
3560 case TemplateArgument::TemplateExpansion:
3561 if (CheckTemplateArgument(TempParm, Arg, ArgumentPackIndex))
3564 Converted.push_back(Arg.getArgument());
3567 case TemplateArgument::Expression:
3568 case TemplateArgument::Type:
3569 // We have a template template parameter but the template
3570 // argument does not refer to a template.
3571 Diag(Arg.getLocation(), diag::err_template_arg_must_be_template)
3572 << getLangOpts().CPlusPlus11;
3575 case TemplateArgument::Declaration:
3576 llvm_unreachable("Declaration argument with template template parameter");
3577 case TemplateArgument::Integral:
3578 llvm_unreachable("Integral argument with template template parameter");
3579 case TemplateArgument::NullPtr:
3580 llvm_unreachable("Null pointer argument with template template parameter");
3582 case TemplateArgument::Pack:
3583 llvm_unreachable("Caller must expand template argument packs");
3589 /// \brief Diagnose an arity mismatch in the
3590 static bool diagnoseArityMismatch(Sema &S, TemplateDecl *Template,
3591 SourceLocation TemplateLoc,
3592 TemplateArgumentListInfo &TemplateArgs) {
3593 TemplateParameterList *Params = Template->getTemplateParameters();
3594 unsigned NumParams = Params->size();
3595 unsigned NumArgs = TemplateArgs.size();
3598 if (NumArgs > NumParams)
3599 Range = SourceRange(TemplateArgs[NumParams].getLocation(),
3600 TemplateArgs.getRAngleLoc());
3601 S.Diag(TemplateLoc, diag::err_template_arg_list_different_arity)
3602 << (NumArgs > NumParams)
3603 << (isa<ClassTemplateDecl>(Template)? 0 :
3604 isa<FunctionTemplateDecl>(Template)? 1 :
3605 isa<TemplateTemplateParmDecl>(Template)? 2 : 3)
3606 << Template << Range;
3607 S.Diag(Template->getLocation(), diag::note_template_decl_here)
3608 << Params->getSourceRange();
3612 /// \brief Check whether the template parameter is a pack expansion, and if so,
3613 /// determine the number of parameters produced by that expansion. For instance:
3616 /// template<typename ...Ts> struct A {
3617 /// template<Ts ...NTs, template<Ts> class ...TTs, typename ...Us> struct B;
3621 /// In \c A<int,int>::B, \c NTs and \c TTs have expanded pack size 2, and \c Us
3622 /// is not a pack expansion, so returns an empty Optional.
3623 static Optional<unsigned> getExpandedPackSize(NamedDecl *Param) {
3624 if (NonTypeTemplateParmDecl *NTTP
3625 = dyn_cast<NonTypeTemplateParmDecl>(Param)) {
3626 if (NTTP->isExpandedParameterPack())
3627 return NTTP->getNumExpansionTypes();
3630 if (TemplateTemplateParmDecl *TTP
3631 = dyn_cast<TemplateTemplateParmDecl>(Param)) {
3632 if (TTP->isExpandedParameterPack())
3633 return TTP->getNumExpansionTemplateParameters();
3639 /// \brief Check that the given template argument list is well-formed
3640 /// for specializing the given template.
3641 bool Sema::CheckTemplateArgumentList(TemplateDecl *Template,
3642 SourceLocation TemplateLoc,
3643 TemplateArgumentListInfo &TemplateArgs,
3644 bool PartialTemplateArgs,
3645 SmallVectorImpl<TemplateArgument> &Converted) {
3646 TemplateParameterList *Params = Template->getTemplateParameters();
3648 SourceLocation RAngleLoc = TemplateArgs.getRAngleLoc();
3650 // C++ [temp.arg]p1:
3651 // [...] The type and form of each template-argument specified in
3652 // a template-id shall match the type and form specified for the
3653 // corresponding parameter declared by the template in its
3654 // template-parameter-list.
3655 bool isTemplateTemplateParameter = isa<TemplateTemplateParmDecl>(Template);
3656 SmallVector<TemplateArgument, 2> ArgumentPack;
3657 unsigned ArgIdx = 0, NumArgs = TemplateArgs.size();
3658 LocalInstantiationScope InstScope(*this, true);
3659 for (TemplateParameterList::iterator Param = Params->begin(),
3660 ParamEnd = Params->end();
3661 Param != ParamEnd; /* increment in loop */) {
3662 // If we have an expanded parameter pack, make sure we don't have too
3664 if (Optional<unsigned> Expansions = getExpandedPackSize(*Param)) {
3665 if (*Expansions == ArgumentPack.size()) {
3666 // We're done with this parameter pack. Pack up its arguments and add
3667 // them to the list.
3668 Converted.push_back(
3669 TemplateArgument::CreatePackCopy(Context,
3670 ArgumentPack.data(),
3671 ArgumentPack.size()));
3672 ArgumentPack.clear();
3674 // This argument is assigned to the next parameter.
3677 } else if (ArgIdx == NumArgs && !PartialTemplateArgs) {
3678 // Not enough arguments for this parameter pack.
3679 Diag(TemplateLoc, diag::err_template_arg_list_different_arity)
3681 << (isa<ClassTemplateDecl>(Template)? 0 :
3682 isa<FunctionTemplateDecl>(Template)? 1 :
3683 isa<TemplateTemplateParmDecl>(Template)? 2 : 3)
3685 Diag(Template->getLocation(), diag::note_template_decl_here)
3686 << Params->getSourceRange();
3691 if (ArgIdx < NumArgs) {
3692 // Check the template argument we were given.
3693 if (CheckTemplateArgument(*Param, TemplateArgs[ArgIdx], Template,
3694 TemplateLoc, RAngleLoc,
3695 ArgumentPack.size(), Converted))
3698 bool PackExpansionIntoNonPack =
3699 TemplateArgs[ArgIdx].getArgument().isPackExpansion() &&
3700 (!(*Param)->isTemplateParameterPack() || getExpandedPackSize(*Param));
3701 if (PackExpansionIntoNonPack && isa<TypeAliasTemplateDecl>(Template)) {
3702 // Core issue 1430: we have a pack expansion as an argument to an
3703 // alias template, and it's not part of a parameter pack. This
3704 // can't be canonicalized, so reject it now.
3705 Diag(TemplateArgs[ArgIdx].getLocation(),
3706 diag::err_alias_template_expansion_into_fixed_list)
3707 << TemplateArgs[ArgIdx].getSourceRange();
3708 Diag((*Param)->getLocation(), diag::note_template_param_here);
3712 // We're now done with this argument.
3715 if ((*Param)->isTemplateParameterPack()) {
3716 // The template parameter was a template parameter pack, so take the
3717 // deduced argument and place it on the argument pack. Note that we
3718 // stay on the same template parameter so that we can deduce more
3720 ArgumentPack.push_back(Converted.pop_back_val());
3722 // Move to the next template parameter.
3726 // If we just saw a pack expansion into a non-pack, then directly convert
3727 // the remaining arguments, because we don't know what parameters they'll
3729 if (PackExpansionIntoNonPack) {
3730 if (!ArgumentPack.empty()) {
3731 // If we were part way through filling in an expanded parameter pack,
3732 // fall back to just producing individual arguments.
3733 Converted.insert(Converted.end(),
3734 ArgumentPack.begin(), ArgumentPack.end());
3735 ArgumentPack.clear();
3738 while (ArgIdx < NumArgs) {
3739 Converted.push_back(TemplateArgs[ArgIdx].getArgument());
3749 // If we're checking a partial template argument list, we're done.
3750 if (PartialTemplateArgs) {
3751 if ((*Param)->isTemplateParameterPack() && !ArgumentPack.empty())
3752 Converted.push_back(TemplateArgument::CreatePackCopy(Context,
3753 ArgumentPack.data(),
3754 ArgumentPack.size()));
3759 // If we have a template parameter pack with no more corresponding
3760 // arguments, just break out now and we'll fill in the argument pack below.
3761 if ((*Param)->isTemplateParameterPack()) {
3762 assert(!getExpandedPackSize(*Param) &&
3763 "Should have dealt with this already");
3765 // A non-expanded parameter pack before the end of the parameter list
3766 // only occurs for an ill-formed template parameter list, unless we've
3767 // got a partial argument list for a function template, so just bail out.
3768 if (Param + 1 != ParamEnd)
3771 Converted.push_back(TemplateArgument::CreatePackCopy(Context,
3772 ArgumentPack.data(),
3773 ArgumentPack.size()));
3774 ArgumentPack.clear();
3780 // Check whether we have a default argument.
3781 TemplateArgumentLoc Arg;
3783 // Retrieve the default template argument from the template
3784 // parameter. For each kind of template parameter, we substitute the
3785 // template arguments provided thus far and any "outer" template arguments
3786 // (when the template parameter was part of a nested template) into
3787 // the default argument.
3788 if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(*Param)) {
3789 if (!TTP->hasDefaultArgument())
3790 return diagnoseArityMismatch(*this, Template, TemplateLoc,
3793 TypeSourceInfo *ArgType = SubstDefaultTemplateArgument(*this,
3802 Arg = TemplateArgumentLoc(TemplateArgument(ArgType->getType()),
3804 } else if (NonTypeTemplateParmDecl *NTTP
3805 = dyn_cast<NonTypeTemplateParmDecl>(*Param)) {
3806 if (!NTTP->hasDefaultArgument())
3807 return diagnoseArityMismatch(*this, Template, TemplateLoc,
3810 ExprResult E = SubstDefaultTemplateArgument(*this, Template,
3818 Expr *Ex = E.getAs<Expr>();
3819 Arg = TemplateArgumentLoc(TemplateArgument(Ex), Ex);
3821 TemplateTemplateParmDecl *TempParm
3822 = cast<TemplateTemplateParmDecl>(*Param);
3824 if (!TempParm->hasDefaultArgument())
3825 return diagnoseArityMismatch(*this, Template, TemplateLoc,
3828 NestedNameSpecifierLoc QualifierLoc;
3829 TemplateName Name = SubstDefaultTemplateArgument(*this, Template,
3838 Arg = TemplateArgumentLoc(TemplateArgument(Name), QualifierLoc,
3839 TempParm->getDefaultArgument().getTemplateNameLoc());
3842 // Introduce an instantiation record that describes where we are using
3843 // the default template argument.
3844 InstantiatingTemplate Inst(*this, RAngleLoc, Template, *Param, Converted,
3845 SourceRange(TemplateLoc, RAngleLoc));
3846 if (Inst.isInvalid())
3849 // Check the default template argument.
3850 if (CheckTemplateArgument(*Param, Arg, Template, TemplateLoc,
3851 RAngleLoc, 0, Converted))
3854 // Core issue 150 (assumed resolution): if this is a template template
3855 // parameter, keep track of the default template arguments from the
3856 // template definition.
3857 if (isTemplateTemplateParameter)
3858 TemplateArgs.addArgument(Arg);
3860 // Move to the next template parameter and argument.
3865 // If we're performing a partial argument substitution, allow any trailing
3866 // pack expansions; they might be empty. This can happen even if
3867 // PartialTemplateArgs is false (the list of arguments is complete but
3868 // still dependent).
3869 if (ArgIdx < NumArgs && CurrentInstantiationScope &&
3870 CurrentInstantiationScope->getPartiallySubstitutedPack()) {
3871 while (ArgIdx < NumArgs &&
3872 TemplateArgs[ArgIdx].getArgument().isPackExpansion())
3873 Converted.push_back(TemplateArgs[ArgIdx++].getArgument());
3876 // If we have any leftover arguments, then there were too many arguments.
3877 // Complain and fail.
3878 if (ArgIdx < NumArgs)
3879 return diagnoseArityMismatch(*this, Template, TemplateLoc, TemplateArgs);
3885 class UnnamedLocalNoLinkageFinder
3886 : public TypeVisitor<UnnamedLocalNoLinkageFinder, bool>
3891 typedef TypeVisitor<UnnamedLocalNoLinkageFinder, bool> inherited;
3894 UnnamedLocalNoLinkageFinder(Sema &S, SourceRange SR) : S(S), SR(SR) { }
3896 bool Visit(QualType T) {
3897 return inherited::Visit(T.getTypePtr());
3900 #define TYPE(Class, Parent) \
3901 bool Visit##Class##Type(const Class##Type *);
3902 #define ABSTRACT_TYPE(Class, Parent) \
3903 bool Visit##Class##Type(const Class##Type *) { return false; }
3904 #define NON_CANONICAL_TYPE(Class, Parent) \
3905 bool Visit##Class##Type(const Class##Type *) { return false; }
3906 #include "clang/AST/TypeNodes.def"
3908 bool VisitTagDecl(const TagDecl *Tag);
3909 bool VisitNestedNameSpecifier(NestedNameSpecifier *NNS);
3913 bool UnnamedLocalNoLinkageFinder::VisitBuiltinType(const BuiltinType*) {
3917 bool UnnamedLocalNoLinkageFinder::VisitComplexType(const ComplexType* T) {
3918 return Visit(T->getElementType());
3921 bool UnnamedLocalNoLinkageFinder::VisitPointerType(const PointerType* T) {
3922 return Visit(T->getPointeeType());
3925 bool UnnamedLocalNoLinkageFinder::VisitBlockPointerType(
3926 const BlockPointerType* T) {
3927 return Visit(T->getPointeeType());
3930 bool UnnamedLocalNoLinkageFinder::VisitLValueReferenceType(
3931 const LValueReferenceType* T) {
3932 return Visit(T->getPointeeType());
3935 bool UnnamedLocalNoLinkageFinder::VisitRValueReferenceType(
3936 const RValueReferenceType* T) {
3937 return Visit(T->getPointeeType());
3940 bool UnnamedLocalNoLinkageFinder::VisitMemberPointerType(
3941 const MemberPointerType* T) {
3942 return Visit(T->getPointeeType()) || Visit(QualType(T->getClass(), 0));
3945 bool UnnamedLocalNoLinkageFinder::VisitConstantArrayType(
3946 const ConstantArrayType* T) {
3947 return Visit(T->getElementType());
3950 bool UnnamedLocalNoLinkageFinder::VisitIncompleteArrayType(
3951 const IncompleteArrayType* T) {
3952 return Visit(T->getElementType());
3955 bool UnnamedLocalNoLinkageFinder::VisitVariableArrayType(
3956 const VariableArrayType* T) {
3957 return Visit(T->getElementType());
3960 bool UnnamedLocalNoLinkageFinder::VisitDependentSizedArrayType(
3961 const DependentSizedArrayType* T) {
3962 return Visit(T->getElementType());
3965 bool UnnamedLocalNoLinkageFinder::VisitDependentSizedExtVectorType(
3966 const DependentSizedExtVectorType* T) {
3967 return Visit(T->getElementType());
3970 bool UnnamedLocalNoLinkageFinder::VisitVectorType(const VectorType* T) {
3971 return Visit(T->getElementType());
3974 bool UnnamedLocalNoLinkageFinder::VisitExtVectorType(const ExtVectorType* T) {
3975 return Visit(T->getElementType());
3978 bool UnnamedLocalNoLinkageFinder::VisitFunctionProtoType(
3979 const FunctionProtoType* T) {
3980 for (const auto &A : T->param_types()) {
3985 return Visit(T->getReturnType());
3988 bool UnnamedLocalNoLinkageFinder::VisitFunctionNoProtoType(
3989 const FunctionNoProtoType* T) {
3990 return Visit(T->getReturnType());
3993 bool UnnamedLocalNoLinkageFinder::VisitUnresolvedUsingType(
3994 const UnresolvedUsingType*) {
3998 bool UnnamedLocalNoLinkageFinder::VisitTypeOfExprType(const TypeOfExprType*) {
4002 bool UnnamedLocalNoLinkageFinder::VisitTypeOfType(const TypeOfType* T) {
4003 return Visit(T->getUnderlyingType());
4006 bool UnnamedLocalNoLinkageFinder::VisitDecltypeType(const DecltypeType*) {
4010 bool UnnamedLocalNoLinkageFinder::VisitUnaryTransformType(
4011 const UnaryTransformType*) {
4015 bool UnnamedLocalNoLinkageFinder::VisitAutoType(const AutoType *T) {
4016 return Visit(T->getDeducedType());
4019 bool UnnamedLocalNoLinkageFinder::VisitRecordType(const RecordType* T) {
4020 return VisitTagDecl(T->getDecl());
4023 bool UnnamedLocalNoLinkageFinder::VisitEnumType(const EnumType* T) {
4024 return VisitTagDecl(T->getDecl());
4027 bool UnnamedLocalNoLinkageFinder::VisitTemplateTypeParmType(
4028 const TemplateTypeParmType*) {
4032 bool UnnamedLocalNoLinkageFinder::VisitSubstTemplateTypeParmPackType(
4033 const SubstTemplateTypeParmPackType *) {
4037 bool UnnamedLocalNoLinkageFinder::VisitTemplateSpecializationType(
4038 const TemplateSpecializationType*) {
4042 bool UnnamedLocalNoLinkageFinder::VisitInjectedClassNameType(
4043 const InjectedClassNameType* T) {
4044 return VisitTagDecl(T->getDecl());
4047 bool UnnamedLocalNoLinkageFinder::VisitDependentNameType(
4048 const DependentNameType* T) {
4049 return VisitNestedNameSpecifier(T->getQualifier());
4052 bool UnnamedLocalNoLinkageFinder::VisitDependentTemplateSpecializationType(
4053 const DependentTemplateSpecializationType* T) {
4054 return VisitNestedNameSpecifier(T->getQualifier());
4057 bool UnnamedLocalNoLinkageFinder::VisitPackExpansionType(
4058 const PackExpansionType* T) {
4059 return Visit(T->getPattern());
4062 bool UnnamedLocalNoLinkageFinder::VisitObjCObjectType(const ObjCObjectType *) {
4066 bool UnnamedLocalNoLinkageFinder::VisitObjCInterfaceType(
4067 const ObjCInterfaceType *) {
4071 bool UnnamedLocalNoLinkageFinder::VisitObjCObjectPointerType(
4072 const ObjCObjectPointerType *) {
4076 bool UnnamedLocalNoLinkageFinder::VisitAtomicType(const AtomicType* T) {
4077 return Visit(T->getValueType());
4080 bool UnnamedLocalNoLinkageFinder::VisitTagDecl(const TagDecl *Tag) {
4081 if (Tag->getDeclContext()->isFunctionOrMethod()) {
4082 S.Diag(SR.getBegin(),
4083 S.getLangOpts().CPlusPlus11 ?
4084 diag::warn_cxx98_compat_template_arg_local_type :
4085 diag::ext_template_arg_local_type)
4086 << S.Context.getTypeDeclType(Tag) << SR;
4090 if (!Tag->hasNameForLinkage()) {
4091 S.Diag(SR.getBegin(),
4092 S.getLangOpts().CPlusPlus11 ?
4093 diag::warn_cxx98_compat_template_arg_unnamed_type :
4094 diag::ext_template_arg_unnamed_type) << SR;
4095 S.Diag(Tag->getLocation(), diag::note_template_unnamed_type_here);
4102 bool UnnamedLocalNoLinkageFinder::VisitNestedNameSpecifier(
4103 NestedNameSpecifier *NNS) {
4104 if (NNS->getPrefix() && VisitNestedNameSpecifier(NNS->getPrefix()))
4107 switch (NNS->getKind()) {
4108 case NestedNameSpecifier::Identifier:
4109 case NestedNameSpecifier::Namespace:
4110 case NestedNameSpecifier::NamespaceAlias:
4111 case NestedNameSpecifier::Global:
4112 case NestedNameSpecifier::Super:
4115 case NestedNameSpecifier::TypeSpec:
4116 case NestedNameSpecifier::TypeSpecWithTemplate:
4117 return Visit(QualType(NNS->getAsType(), 0));
4119 llvm_unreachable("Invalid NestedNameSpecifier::Kind!");
4123 /// \brief Check a template argument against its corresponding
4124 /// template type parameter.
4126 /// This routine implements the semantics of C++ [temp.arg.type]. It
4127 /// returns true if an error occurred, and false otherwise.
4128 bool Sema::CheckTemplateArgument(TemplateTypeParmDecl *Param,
4129 TypeSourceInfo *ArgInfo) {
4130 assert(ArgInfo && "invalid TypeSourceInfo");
4131 QualType Arg = ArgInfo->getType();
4132 SourceRange SR = ArgInfo->getTypeLoc().getSourceRange();
4134 if (Arg->isVariablyModifiedType()) {
4135 return Diag(SR.getBegin(), diag::err_variably_modified_template_arg) << Arg;
4136 } else if (Context.hasSameUnqualifiedType(Arg, Context.OverloadTy)) {
4137 return Diag(SR.getBegin(), diag::err_template_arg_overload_type) << SR;
4140 // C++03 [temp.arg.type]p2:
4141 // A local type, a type with no linkage, an unnamed type or a type
4142 // compounded from any of these types shall not be used as a
4143 // template-argument for a template type-parameter.
4145 // C++11 allows these, and even in C++03 we allow them as an extension with
4148 if (LangOpts.CPlusPlus11)
4150 !Diags.isIgnored(diag::warn_cxx98_compat_template_arg_unnamed_type,
4152 !Diags.isIgnored(diag::warn_cxx98_compat_template_arg_local_type,
4155 NeedsCheck = Arg->hasUnnamedOrLocalType();
4158 UnnamedLocalNoLinkageFinder Finder(*this, SR);
4159 (void)Finder.Visit(Context.getCanonicalType(Arg));
4165 enum NullPointerValueKind {
4171 /// \brief Determine whether the given template argument is a null pointer
4172 /// value of the appropriate type.
4173 static NullPointerValueKind
4174 isNullPointerValueTemplateArgument(Sema &S, NonTypeTemplateParmDecl *Param,
4175 QualType ParamType, Expr *Arg) {
4176 if (Arg->isValueDependent() || Arg->isTypeDependent())
4177 return NPV_NotNullPointer;
4179 if (!S.getLangOpts().CPlusPlus11)
4180 return NPV_NotNullPointer;
4182 // Determine whether we have a constant expression.
4183 ExprResult ArgRV = S.DefaultFunctionArrayConversion(Arg);
4184 if (ArgRV.isInvalid())
4188 Expr::EvalResult EvalResult;
4189 SmallVector<PartialDiagnosticAt, 8> Notes;
4190 EvalResult.Diag = &Notes;
4191 if (!Arg->EvaluateAsRValue(EvalResult, S.Context) ||
4192 EvalResult.HasSideEffects) {
4193 SourceLocation DiagLoc = Arg->getExprLoc();
4195 // If our only note is the usual "invalid subexpression" note, just point
4196 // the caret at its location rather than producing an essentially
4198 if (Notes.size() == 1 && Notes[0].second.getDiagID() ==
4199 diag::note_invalid_subexpr_in_const_expr) {
4200 DiagLoc = Notes[0].first;
4204 S.Diag(DiagLoc, diag::err_template_arg_not_address_constant)
4205 << Arg->getType() << Arg->getSourceRange();
4206 for (unsigned I = 0, N = Notes.size(); I != N; ++I)
4207 S.Diag(Notes[I].first, Notes[I].second);
4209 S.Diag(Param->getLocation(), diag::note_template_param_here);
4213 // C++11 [temp.arg.nontype]p1:
4214 // - an address constant expression of type std::nullptr_t
4215 if (Arg->getType()->isNullPtrType())
4216 return NPV_NullPointer;
4218 // - a constant expression that evaluates to a null pointer value (4.10); or
4219 // - a constant expression that evaluates to a null member pointer value
4221 if ((EvalResult.Val.isLValue() && !EvalResult.Val.getLValueBase()) ||
4222 (EvalResult.Val.isMemberPointer() &&
4223 !EvalResult.Val.getMemberPointerDecl())) {
4224 // If our expression has an appropriate type, we've succeeded.
4225 bool ObjCLifetimeConversion;
4226 if (S.Context.hasSameUnqualifiedType(Arg->getType(), ParamType) ||
4227 S.IsQualificationConversion(Arg->getType(), ParamType, false,
4228 ObjCLifetimeConversion))
4229 return NPV_NullPointer;
4231 // The types didn't match, but we know we got a null pointer; complain,
4232 // then recover as if the types were correct.
4233 S.Diag(Arg->getExprLoc(), diag::err_template_arg_wrongtype_null_constant)
4234 << Arg->getType() << ParamType << Arg->getSourceRange();
4235 S.Diag(Param->getLocation(), diag::note_template_param_here);
4236 return NPV_NullPointer;
4239 // If we don't have a null pointer value, but we do have a NULL pointer
4240 // constant, suggest a cast to the appropriate type.
4241 if (Arg->isNullPointerConstant(S.Context, Expr::NPC_NeverValueDependent)) {
4242 std::string Code = "static_cast<" + ParamType.getAsString() + ">(";
4243 S.Diag(Arg->getExprLoc(), diag::err_template_arg_untyped_null_constant)
4244 << ParamType << FixItHint::CreateInsertion(Arg->getLocStart(), Code)
4245 << FixItHint::CreateInsertion(S.getLocForEndOfToken(Arg->getLocEnd()),
4247 S.Diag(Param->getLocation(), diag::note_template_param_here);
4248 return NPV_NullPointer;
4251 // FIXME: If we ever want to support general, address-constant expressions
4252 // as non-type template arguments, we should return the ExprResult here to
4253 // be interpreted by the caller.
4254 return NPV_NotNullPointer;
4257 /// \brief Checks whether the given template argument is compatible with its
4258 /// template parameter.
4259 static bool CheckTemplateArgumentIsCompatibleWithParameter(
4260 Sema &S, NonTypeTemplateParmDecl *Param, QualType ParamType, Expr *ArgIn,
4261 Expr *Arg, QualType ArgType) {
4262 bool ObjCLifetimeConversion;
4263 if (ParamType->isPointerType() &&
4264 !ParamType->getAs<PointerType>()->getPointeeType()->isFunctionType() &&
4265 S.IsQualificationConversion(ArgType, ParamType, false,
4266 ObjCLifetimeConversion)) {
4267 // For pointer-to-object types, qualification conversions are
4270 if (const ReferenceType *ParamRef = ParamType->getAs<ReferenceType>()) {
4271 if (!ParamRef->getPointeeType()->isFunctionType()) {
4272 // C++ [temp.arg.nontype]p5b3:
4273 // For a non-type template-parameter of type reference to
4274 // object, no conversions apply. The type referred to by the
4275 // reference may be more cv-qualified than the (otherwise
4276 // identical) type of the template- argument. The
4277 // template-parameter is bound directly to the
4278 // template-argument, which shall be an lvalue.
4280 // FIXME: Other qualifiers?
4281 unsigned ParamQuals = ParamRef->getPointeeType().getCVRQualifiers();
4282 unsigned ArgQuals = ArgType.getCVRQualifiers();
4284 if ((ParamQuals | ArgQuals) != ParamQuals) {
4285 S.Diag(Arg->getLocStart(),
4286 diag::err_template_arg_ref_bind_ignores_quals)
4287 << ParamType << Arg->getType() << Arg->getSourceRange();
4288 S.Diag(Param->getLocation(), diag::note_template_param_here);
4294 // At this point, the template argument refers to an object or
4295 // function with external linkage. We now need to check whether the
4296 // argument and parameter types are compatible.
4297 if (!S.Context.hasSameUnqualifiedType(ArgType,
4298 ParamType.getNonReferenceType())) {
4299 // We can't perform this conversion or binding.
4300 if (ParamType->isReferenceType())
4301 S.Diag(Arg->getLocStart(), diag::err_template_arg_no_ref_bind)
4302 << ParamType << ArgIn->getType() << Arg->getSourceRange();
4304 S.Diag(Arg->getLocStart(), diag::err_template_arg_not_convertible)
4305 << ArgIn->getType() << ParamType << Arg->getSourceRange();
4306 S.Diag(Param->getLocation(), diag::note_template_param_here);
4314 /// \brief Checks whether the given template argument is the address
4315 /// of an object or function according to C++ [temp.arg.nontype]p1.
4317 CheckTemplateArgumentAddressOfObjectOrFunction(Sema &S,
4318 NonTypeTemplateParmDecl *Param,
4321 TemplateArgument &Converted) {
4322 bool Invalid = false;
4324 QualType ArgType = Arg->getType();
4326 bool AddressTaken = false;
4327 SourceLocation AddrOpLoc;
4328 if (S.getLangOpts().MicrosoftExt) {
4329 // Microsoft Visual C++ strips all casts, allows an arbitrary number of
4330 // dereference and address-of operators.
4331 Arg = Arg->IgnoreParenCasts();
4333 bool ExtWarnMSTemplateArg = false;
4334 UnaryOperatorKind FirstOpKind;
4335 SourceLocation FirstOpLoc;
4336 while (UnaryOperator *UnOp = dyn_cast<UnaryOperator>(Arg)) {
4337 UnaryOperatorKind UnOpKind = UnOp->getOpcode();
4338 if (UnOpKind == UO_Deref)
4339 ExtWarnMSTemplateArg = true;
4340 if (UnOpKind == UO_AddrOf || UnOpKind == UO_Deref) {
4341 Arg = UnOp->getSubExpr()->IgnoreParenCasts();
4342 if (!AddrOpLoc.isValid()) {
4343 FirstOpKind = UnOpKind;
4344 FirstOpLoc = UnOp->getOperatorLoc();
4349 if (FirstOpLoc.isValid()) {
4350 if (ExtWarnMSTemplateArg)
4351 S.Diag(ArgIn->getLocStart(), diag::ext_ms_deref_template_argument)
4352 << ArgIn->getSourceRange();
4354 if (FirstOpKind == UO_AddrOf)
4355 AddressTaken = true;
4356 else if (Arg->getType()->isPointerType()) {
4357 // We cannot let pointers get dereferenced here, that is obviously not a
4358 // constant expression.
4359 assert(FirstOpKind == UO_Deref);
4360 S.Diag(Arg->getLocStart(), diag::err_template_arg_not_decl_ref)
4361 << Arg->getSourceRange();
4365 // See through any implicit casts we added to fix the type.
4366 Arg = Arg->IgnoreImpCasts();
4368 // C++ [temp.arg.nontype]p1:
4370 // A template-argument for a non-type, non-template
4371 // template-parameter shall be one of: [...]
4373 // -- the address of an object or function with external
4374 // linkage, including function templates and function
4375 // template-ids but excluding non-static class members,
4376 // expressed as & id-expression where the & is optional if
4377 // the name refers to a function or array, or if the
4378 // corresponding template-parameter is a reference; or
4380 // In C++98/03 mode, give an extension warning on any extra parentheses.
4381 // See http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_defects.html#773
4382 bool ExtraParens = false;
4383 while (ParenExpr *Parens = dyn_cast<ParenExpr>(Arg)) {
4384 if (!Invalid && !ExtraParens) {
4385 S.Diag(Arg->getLocStart(),
4386 S.getLangOpts().CPlusPlus11
4387 ? diag::warn_cxx98_compat_template_arg_extra_parens
4388 : diag::ext_template_arg_extra_parens)
4389 << Arg->getSourceRange();
4393 Arg = Parens->getSubExpr();
4396 while (SubstNonTypeTemplateParmExpr *subst =
4397 dyn_cast<SubstNonTypeTemplateParmExpr>(Arg))
4398 Arg = subst->getReplacement()->IgnoreImpCasts();
4400 if (UnaryOperator *UnOp = dyn_cast<UnaryOperator>(Arg)) {
4401 if (UnOp->getOpcode() == UO_AddrOf) {
4402 Arg = UnOp->getSubExpr();
4403 AddressTaken = true;
4404 AddrOpLoc = UnOp->getOperatorLoc();
4408 while (SubstNonTypeTemplateParmExpr *subst =
4409 dyn_cast<SubstNonTypeTemplateParmExpr>(Arg))
4410 Arg = subst->getReplacement()->IgnoreImpCasts();
4413 DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Arg);
4414 ValueDecl *Entity = DRE ? DRE->getDecl() : nullptr;
4416 // If our parameter has pointer type, check for a null template value.
4417 if (ParamType->isPointerType() || ParamType->isNullPtrType()) {
4418 NullPointerValueKind NPV;
4419 // dllimport'd entities aren't constant but are available inside of template
4421 if (Entity && Entity->hasAttr<DLLImportAttr>())
4422 NPV = NPV_NotNullPointer;
4424 NPV = isNullPointerValueTemplateArgument(S, Param, ParamType, ArgIn);
4426 case NPV_NullPointer:
4427 S.Diag(Arg->getExprLoc(), diag::warn_cxx98_compat_template_arg_null);
4428 Converted = TemplateArgument(S.Context.getCanonicalType(ParamType),
4429 /*isNullPtr=*/true);
4435 case NPV_NotNullPointer:
4440 // Stop checking the precise nature of the argument if it is value dependent,
4441 // it should be checked when instantiated.
4442 if (Arg->isValueDependent()) {
4443 Converted = TemplateArgument(ArgIn);
4447 if (isa<CXXUuidofExpr>(Arg)) {
4448 if (CheckTemplateArgumentIsCompatibleWithParameter(S, Param, ParamType,
4449 ArgIn, Arg, ArgType))
4452 Converted = TemplateArgument(ArgIn);
4457 S.Diag(Arg->getLocStart(), diag::err_template_arg_not_decl_ref)
4458 << Arg->getSourceRange();
4459 S.Diag(Param->getLocation(), diag::note_template_param_here);
4463 // Cannot refer to non-static data members
4464 if (isa<FieldDecl>(Entity) || isa<IndirectFieldDecl>(Entity)) {
4465 S.Diag(Arg->getLocStart(), diag::err_template_arg_field)
4466 << Entity << Arg->getSourceRange();
4467 S.Diag(Param->getLocation(), diag::note_template_param_here);
4471 // Cannot refer to non-static member functions
4472 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Entity)) {
4473 if (!Method->isStatic()) {
4474 S.Diag(Arg->getLocStart(), diag::err_template_arg_method)
4475 << Method << Arg->getSourceRange();
4476 S.Diag(Param->getLocation(), diag::note_template_param_here);
4481 FunctionDecl *Func = dyn_cast<FunctionDecl>(Entity);
4482 VarDecl *Var = dyn_cast<VarDecl>(Entity);
4484 // A non-type template argument must refer to an object or function.
4485 if (!Func && !Var) {
4486 // We found something, but we don't know specifically what it is.
4487 S.Diag(Arg->getLocStart(), diag::err_template_arg_not_object_or_func)
4488 << Arg->getSourceRange();
4489 S.Diag(DRE->getDecl()->getLocation(), diag::note_template_arg_refers_here);
4493 // Address / reference template args must have external linkage in C++98.
4494 if (Entity->getFormalLinkage() == InternalLinkage) {
4495 S.Diag(Arg->getLocStart(), S.getLangOpts().CPlusPlus11 ?
4496 diag::warn_cxx98_compat_template_arg_object_internal :
4497 diag::ext_template_arg_object_internal)
4498 << !Func << Entity << Arg->getSourceRange();
4499 S.Diag(Entity->getLocation(), diag::note_template_arg_internal_object)
4501 } else if (!Entity->hasLinkage()) {
4502 S.Diag(Arg->getLocStart(), diag::err_template_arg_object_no_linkage)
4503 << !Func << Entity << Arg->getSourceRange();
4504 S.Diag(Entity->getLocation(), diag::note_template_arg_internal_object)
4510 // If the template parameter has pointer type, the function decays.
4511 if (ParamType->isPointerType() && !AddressTaken)
4512 ArgType = S.Context.getPointerType(Func->getType());
4513 else if (AddressTaken && ParamType->isReferenceType()) {
4514 // If we originally had an address-of operator, but the
4515 // parameter has reference type, complain and (if things look
4516 // like they will work) drop the address-of operator.
4517 if (!S.Context.hasSameUnqualifiedType(Func->getType(),
4518 ParamType.getNonReferenceType())) {
4519 S.Diag(AddrOpLoc, diag::err_template_arg_address_of_non_pointer)
4521 S.Diag(Param->getLocation(), diag::note_template_param_here);
4525 S.Diag(AddrOpLoc, diag::err_template_arg_address_of_non_pointer)
4527 << FixItHint::CreateRemoval(AddrOpLoc);
4528 S.Diag(Param->getLocation(), diag::note_template_param_here);
4530 ArgType = Func->getType();
4533 // A value of reference type is not an object.
4534 if (Var->getType()->isReferenceType()) {
4535 S.Diag(Arg->getLocStart(),
4536 diag::err_template_arg_reference_var)
4537 << Var->getType() << Arg->getSourceRange();
4538 S.Diag(Param->getLocation(), diag::note_template_param_here);
4542 // A template argument must have static storage duration.
4543 if (Var->getTLSKind()) {
4544 S.Diag(Arg->getLocStart(), diag::err_template_arg_thread_local)
4545 << Arg->getSourceRange();
4546 S.Diag(Var->getLocation(), diag::note_template_arg_refers_here);
4550 // If the template parameter has pointer type, we must have taken
4551 // the address of this object.
4552 if (ParamType->isReferenceType()) {
4554 // If we originally had an address-of operator, but the
4555 // parameter has reference type, complain and (if things look
4556 // like they will work) drop the address-of operator.
4557 if (!S.Context.hasSameUnqualifiedType(Var->getType(),
4558 ParamType.getNonReferenceType())) {
4559 S.Diag(AddrOpLoc, diag::err_template_arg_address_of_non_pointer)
4561 S.Diag(Param->getLocation(), diag::note_template_param_here);
4565 S.Diag(AddrOpLoc, diag::err_template_arg_address_of_non_pointer)
4567 << FixItHint::CreateRemoval(AddrOpLoc);
4568 S.Diag(Param->getLocation(), diag::note_template_param_here);
4570 ArgType = Var->getType();
4572 } else if (!AddressTaken && ParamType->isPointerType()) {
4573 if (Var->getType()->isArrayType()) {
4574 // Array-to-pointer decay.
4575 ArgType = S.Context.getArrayDecayedType(Var->getType());
4577 // If the template parameter has pointer type but the address of
4578 // this object was not taken, complain and (possibly) recover by
4579 // taking the address of the entity.
4580 ArgType = S.Context.getPointerType(Var->getType());
4581 if (!S.Context.hasSameUnqualifiedType(ArgType, ParamType)) {
4582 S.Diag(Arg->getLocStart(), diag::err_template_arg_not_address_of)
4584 S.Diag(Param->getLocation(), diag::note_template_param_here);
4588 S.Diag(Arg->getLocStart(), diag::err_template_arg_not_address_of)
4590 << FixItHint::CreateInsertion(Arg->getLocStart(), "&");
4592 S.Diag(Param->getLocation(), diag::note_template_param_here);
4597 if (CheckTemplateArgumentIsCompatibleWithParameter(S, Param, ParamType, ArgIn,
4601 // Create the template argument.
4603 TemplateArgument(cast<ValueDecl>(Entity->getCanonicalDecl()), ParamType);
4604 S.MarkAnyDeclReferenced(Arg->getLocStart(), Entity, false);
4608 /// \brief Checks whether the given template argument is a pointer to
4609 /// member constant according to C++ [temp.arg.nontype]p1.
4610 static bool CheckTemplateArgumentPointerToMember(Sema &S,
4611 NonTypeTemplateParmDecl *Param,
4614 TemplateArgument &Converted) {
4615 bool Invalid = false;
4617 // Check for a null pointer value.
4618 Expr *Arg = ResultArg;
4619 switch (isNullPointerValueTemplateArgument(S, Param, ParamType, Arg)) {
4622 case NPV_NullPointer:
4623 S.Diag(Arg->getExprLoc(), diag::warn_cxx98_compat_template_arg_null);
4624 Converted = TemplateArgument(S.Context.getCanonicalType(ParamType),
4626 if (S.Context.getTargetInfo().getCXXABI().isMicrosoft())
4627 S.RequireCompleteType(Arg->getExprLoc(), ParamType, 0);
4629 case NPV_NotNullPointer:
4633 bool ObjCLifetimeConversion;
4634 if (S.IsQualificationConversion(Arg->getType(),
4635 ParamType.getNonReferenceType(),
4636 false, ObjCLifetimeConversion)) {
4637 Arg = S.ImpCastExprToType(Arg, ParamType, CK_NoOp,
4638 Arg->getValueKind()).get();
4640 } else if (!S.Context.hasSameUnqualifiedType(Arg->getType(),
4641 ParamType.getNonReferenceType())) {
4642 // We can't perform this conversion.
4643 S.Diag(Arg->getLocStart(), diag::err_template_arg_not_convertible)
4644 << Arg->getType() << ParamType << Arg->getSourceRange();
4645 S.Diag(Param->getLocation(), diag::note_template_param_here);
4649 // See through any implicit casts we added to fix the type.
4650 while (ImplicitCastExpr *Cast = dyn_cast<ImplicitCastExpr>(Arg))
4651 Arg = Cast->getSubExpr();
4653 // C++ [temp.arg.nontype]p1:
4655 // A template-argument for a non-type, non-template
4656 // template-parameter shall be one of: [...]
4658 // -- a pointer to member expressed as described in 5.3.1.
4659 DeclRefExpr *DRE = nullptr;
4661 // In C++98/03 mode, give an extension warning on any extra parentheses.
4662 // See http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_defects.html#773
4663 bool ExtraParens = false;
4664 while (ParenExpr *Parens = dyn_cast<ParenExpr>(Arg)) {
4665 if (!Invalid && !ExtraParens) {
4666 S.Diag(Arg->getLocStart(),
4667 S.getLangOpts().CPlusPlus11 ?
4668 diag::warn_cxx98_compat_template_arg_extra_parens :
4669 diag::ext_template_arg_extra_parens)
4670 << Arg->getSourceRange();
4674 Arg = Parens->getSubExpr();
4677 while (SubstNonTypeTemplateParmExpr *subst =
4678 dyn_cast<SubstNonTypeTemplateParmExpr>(Arg))
4679 Arg = subst->getReplacement()->IgnoreImpCasts();
4681 // A pointer-to-member constant written &Class::member.
4682 if (UnaryOperator *UnOp = dyn_cast<UnaryOperator>(Arg)) {
4683 if (UnOp->getOpcode() == UO_AddrOf) {
4684 DRE = dyn_cast<DeclRefExpr>(UnOp->getSubExpr());
4685 if (DRE && !DRE->getQualifier())
4689 // A constant of pointer-to-member type.
4690 else if ((DRE = dyn_cast<DeclRefExpr>(Arg))) {
4691 if (ValueDecl *VD = dyn_cast<ValueDecl>(DRE->getDecl())) {
4692 if (VD->getType()->isMemberPointerType()) {
4693 if (isa<NonTypeTemplateParmDecl>(VD)) {
4694 if (Arg->isTypeDependent() || Arg->isValueDependent()) {
4695 Converted = TemplateArgument(Arg);
4697 VD = cast<ValueDecl>(VD->getCanonicalDecl());
4698 Converted = TemplateArgument(VD, ParamType);
4709 return S.Diag(Arg->getLocStart(),
4710 diag::err_template_arg_not_pointer_to_member_form)
4711 << Arg->getSourceRange();
4713 if (isa<FieldDecl>(DRE->getDecl()) ||
4714 isa<IndirectFieldDecl>(DRE->getDecl()) ||
4715 isa<CXXMethodDecl>(DRE->getDecl())) {
4716 assert((isa<FieldDecl>(DRE->getDecl()) ||
4717 isa<IndirectFieldDecl>(DRE->getDecl()) ||
4718 !cast<CXXMethodDecl>(DRE->getDecl())->isStatic()) &&
4719 "Only non-static member pointers can make it here");
4721 // Okay: this is the address of a non-static member, and therefore
4722 // a member pointer constant.
4723 if (Arg->isTypeDependent() || Arg->isValueDependent()) {
4724 Converted = TemplateArgument(Arg);
4726 ValueDecl *D = cast<ValueDecl>(DRE->getDecl()->getCanonicalDecl());
4727 Converted = TemplateArgument(D, ParamType);
4732 // We found something else, but we don't know specifically what it is.
4733 S.Diag(Arg->getLocStart(),
4734 diag::err_template_arg_not_pointer_to_member_form)
4735 << Arg->getSourceRange();
4736 S.Diag(DRE->getDecl()->getLocation(), diag::note_template_arg_refers_here);
4740 /// \brief Check a template argument against its corresponding
4741 /// non-type template parameter.
4743 /// This routine implements the semantics of C++ [temp.arg.nontype].
4744 /// If an error occurred, it returns ExprError(); otherwise, it
4745 /// returns the converted template argument. \p
4746 /// InstantiatedParamType is the type of the non-type template
4747 /// parameter after it has been instantiated.
4748 ExprResult Sema::CheckTemplateArgument(NonTypeTemplateParmDecl *Param,
4749 QualType InstantiatedParamType, Expr *Arg,
4750 TemplateArgument &Converted,
4751 CheckTemplateArgumentKind CTAK) {
4752 SourceLocation StartLoc = Arg->getLocStart();
4754 // If either the parameter has a dependent type or the argument is
4755 // type-dependent, there's nothing we can check now.
4756 if (InstantiatedParamType->isDependentType() || Arg->isTypeDependent()) {
4757 // FIXME: Produce a cloned, canonical expression?
4758 Converted = TemplateArgument(Arg);
4762 QualType ParamType = InstantiatedParamType;
4763 if (getLangOpts().CPlusPlus1z) {
4764 // FIXME: We can do some limited checking for a value-dependent but not
4765 // type-dependent argument.
4766 if (Arg->isValueDependent()) {
4767 Converted = TemplateArgument(Arg);
4771 // C++1z [temp.arg.nontype]p1:
4772 // A template-argument for a non-type template parameter shall be
4773 // a converted constant expression of the type of the template-parameter.
4775 ExprResult ArgResult = CheckConvertedConstantExpression(
4776 Arg, ParamType, Value, CCEK_TemplateArg);
4777 if (ArgResult.isInvalid())
4780 // Convert the APValue to a TemplateArgument.
4781 switch (Value.getKind()) {
4782 case APValue::Uninitialized:
4783 assert(ParamType->isNullPtrType());
4784 Converted = TemplateArgument(ParamType, /*isNullPtr*/true);
4787 assert(ParamType->isIntegralOrEnumerationType());
4788 Converted = TemplateArgument(Context, Value.getInt(), ParamType);
4790 case APValue::MemberPointer: {
4791 assert(ParamType->isMemberPointerType());
4793 // FIXME: We need TemplateArgument representation and mangling for these.
4794 if (!Value.getMemberPointerPath().empty()) {
4795 Diag(Arg->getLocStart(),
4796 diag::err_template_arg_member_ptr_base_derived_not_supported)
4797 << Value.getMemberPointerDecl() << ParamType
4798 << Arg->getSourceRange();
4802 auto *VD = const_cast<ValueDecl*>(Value.getMemberPointerDecl());
4803 Converted = VD ? TemplateArgument(VD, ParamType)
4804 : TemplateArgument(ParamType, /*isNullPtr*/true);
4807 case APValue::LValue: {
4808 // For a non-type template-parameter of pointer or reference type,
4809 // the value of the constant expression shall not refer to
4810 assert(ParamType->isPointerType() || ParamType->isReferenceType());
4811 // -- a temporary object
4812 // -- a string literal
4813 // -- the result of a typeid expression, or
4814 // -- a predefind __func__ variable
4815 if (auto *E = Value.getLValueBase().dyn_cast<const Expr*>()) {
4816 if (isa<CXXUuidofExpr>(E)) {
4817 Converted = TemplateArgument(const_cast<Expr*>(E));
4820 Diag(Arg->getLocStart(), diag::err_template_arg_not_decl_ref)
4821 << Arg->getSourceRange();
4824 auto *VD = const_cast<ValueDecl *>(
4825 Value.getLValueBase().dyn_cast<const ValueDecl *>());
4827 if (Value.hasLValuePath() && Value.getLValuePath().size() == 1 &&
4828 VD && VD->getType()->isArrayType() &&
4829 Value.getLValuePath()[0].ArrayIndex == 0 &&
4830 !Value.isLValueOnePastTheEnd() && ParamType->isPointerType()) {
4831 // Per defect report (no number yet):
4832 // ... other than a pointer to the first element of a complete array
4834 } else if (!Value.hasLValuePath() || Value.getLValuePath().size() ||
4835 Value.isLValueOnePastTheEnd()) {
4836 Diag(StartLoc, diag::err_non_type_template_arg_subobject)
4837 << Value.getAsString(Context, ParamType);
4840 assert((VD || ParamType->isPointerType()) &&
4841 "null reference should not be a constant expression");
4842 Converted = VD ? TemplateArgument(VD, ParamType)
4843 : TemplateArgument(ParamType, /*isNullPtr*/true);
4846 case APValue::AddrLabelDiff:
4847 return Diag(StartLoc, diag::err_non_type_template_arg_addr_label_diff);
4848 case APValue::Float:
4849 case APValue::ComplexInt:
4850 case APValue::ComplexFloat:
4851 case APValue::Vector:
4852 case APValue::Array:
4853 case APValue::Struct:
4854 case APValue::Union:
4855 llvm_unreachable("invalid kind for template argument");
4858 return ArgResult.get();
4861 // C++ [temp.arg.nontype]p5:
4862 // The following conversions are performed on each expression used
4863 // as a non-type template-argument. If a non-type
4864 // template-argument cannot be converted to the type of the
4865 // corresponding template-parameter then the program is
4867 if (ParamType->isIntegralOrEnumerationType()) {
4869 // -- for a non-type template-parameter of integral or
4870 // enumeration type, conversions permitted in a converted
4871 // constant expression are applied.
4874 // -- for a non-type template-parameter of integral or
4875 // enumeration type, integral promotions (4.5) and integral
4876 // conversions (4.7) are applied.
4878 if (CTAK == CTAK_Deduced &&
4879 !Context.hasSameUnqualifiedType(ParamType, Arg->getType())) {
4880 // C++ [temp.deduct.type]p17:
4881 // If, in the declaration of a function template with a non-type
4882 // template-parameter, the non-type template-parameter is used
4883 // in an expression in the function parameter-list and, if the
4884 // corresponding template-argument is deduced, the
4885 // template-argument type shall match the type of the
4886 // template-parameter exactly, except that a template-argument
4887 // deduced from an array bound may be of any integral type.
4888 Diag(StartLoc, diag::err_deduced_non_type_template_arg_type_mismatch)
4889 << Arg->getType().getUnqualifiedType()
4890 << ParamType.getUnqualifiedType();
4891 Diag(Param->getLocation(), diag::note_template_param_here);
4895 if (getLangOpts().CPlusPlus11) {
4896 // We can't check arbitrary value-dependent arguments.
4897 // FIXME: If there's no viable conversion to the template parameter type,
4898 // we should be able to diagnose that prior to instantiation.
4899 if (Arg->isValueDependent()) {
4900 Converted = TemplateArgument(Arg);
4904 // C++ [temp.arg.nontype]p1:
4905 // A template-argument for a non-type, non-template template-parameter
4908 // -- for a non-type template-parameter of integral or enumeration
4909 // type, a converted constant expression of the type of the
4910 // template-parameter; or
4912 ExprResult ArgResult =
4913 CheckConvertedConstantExpression(Arg, ParamType, Value,
4915 if (ArgResult.isInvalid())
4918 // Widen the argument value to sizeof(parameter type). This is almost
4919 // always a no-op, except when the parameter type is bool. In
4920 // that case, this may extend the argument from 1 bit to 8 bits.
4921 QualType IntegerType = ParamType;
4922 if (const EnumType *Enum = IntegerType->getAs<EnumType>())
4923 IntegerType = Enum->getDecl()->getIntegerType();
4924 Value = Value.extOrTrunc(Context.getTypeSize(IntegerType));
4926 Converted = TemplateArgument(Context, Value,
4927 Context.getCanonicalType(ParamType));
4931 ExprResult ArgResult = DefaultLvalueConversion(Arg);
4932 if (ArgResult.isInvalid())
4934 Arg = ArgResult.get();
4936 QualType ArgType = Arg->getType();
4938 // C++ [temp.arg.nontype]p1:
4939 // A template-argument for a non-type, non-template
4940 // template-parameter shall be one of:
4942 // -- an integral constant-expression of integral or enumeration
4944 // -- the name of a non-type template-parameter; or
4945 SourceLocation NonConstantLoc;
4947 if (!ArgType->isIntegralOrEnumerationType()) {
4948 Diag(Arg->getLocStart(),
4949 diag::err_template_arg_not_integral_or_enumeral)
4950 << ArgType << Arg->getSourceRange();
4951 Diag(Param->getLocation(), diag::note_template_param_here);
4953 } else if (!Arg->isValueDependent()) {
4954 class TmplArgICEDiagnoser : public VerifyICEDiagnoser {
4958 TmplArgICEDiagnoser(QualType T) : T(T) { }
4960 void diagnoseNotICE(Sema &S, SourceLocation Loc,
4961 SourceRange SR) override {
4962 S.Diag(Loc, diag::err_template_arg_not_ice) << T << SR;
4964 } Diagnoser(ArgType);
4966 Arg = VerifyIntegerConstantExpression(Arg, &Value, Diagnoser,
4972 // From here on out, all we care about are the unqualified forms
4973 // of the parameter and argument types.
4974 ParamType = ParamType.getUnqualifiedType();
4975 ArgType = ArgType.getUnqualifiedType();
4977 // Try to convert the argument to the parameter's type.
4978 if (Context.hasSameType(ParamType, ArgType)) {
4979 // Okay: no conversion necessary
4980 } else if (ParamType->isBooleanType()) {
4981 // This is an integral-to-boolean conversion.
4982 Arg = ImpCastExprToType(Arg, ParamType, CK_IntegralToBoolean).get();
4983 } else if (IsIntegralPromotion(Arg, ArgType, ParamType) ||
4984 !ParamType->isEnumeralType()) {
4985 // This is an integral promotion or conversion.
4986 Arg = ImpCastExprToType(Arg, ParamType, CK_IntegralCast).get();
4988 // We can't perform this conversion.
4989 Diag(Arg->getLocStart(),
4990 diag::err_template_arg_not_convertible)
4991 << Arg->getType() << InstantiatedParamType << Arg->getSourceRange();
4992 Diag(Param->getLocation(), diag::note_template_param_here);
4996 // Add the value of this argument to the list of converted
4997 // arguments. We use the bitwidth and signedness of the template
4999 if (Arg->isValueDependent()) {
5000 // The argument is value-dependent. Create a new
5001 // TemplateArgument with the converted expression.
5002 Converted = TemplateArgument(Arg);
5006 QualType IntegerType = Context.getCanonicalType(ParamType);
5007 if (const EnumType *Enum = IntegerType->getAs<EnumType>())
5008 IntegerType = Context.getCanonicalType(Enum->getDecl()->getIntegerType());
5010 if (ParamType->isBooleanType()) {
5011 // Value must be zero or one.
5013 unsigned AllowedBits = Context.getTypeSize(IntegerType);
5014 if (Value.getBitWidth() != AllowedBits)
5015 Value = Value.extOrTrunc(AllowedBits);
5016 Value.setIsSigned(IntegerType->isSignedIntegerOrEnumerationType());
5018 llvm::APSInt OldValue = Value;
5020 // Coerce the template argument's value to the value it will have
5021 // based on the template parameter's type.
5022 unsigned AllowedBits = Context.getTypeSize(IntegerType);
5023 if (Value.getBitWidth() != AllowedBits)
5024 Value = Value.extOrTrunc(AllowedBits);
5025 Value.setIsSigned(IntegerType->isSignedIntegerOrEnumerationType());
5027 // Complain if an unsigned parameter received a negative value.
5028 if (IntegerType->isUnsignedIntegerOrEnumerationType()
5029 && (OldValue.isSigned() && OldValue.isNegative())) {
5030 Diag(Arg->getLocStart(), diag::warn_template_arg_negative)
5031 << OldValue.toString(10) << Value.toString(10) << Param->getType()
5032 << Arg->getSourceRange();
5033 Diag(Param->getLocation(), diag::note_template_param_here);
5036 // Complain if we overflowed the template parameter's type.
5037 unsigned RequiredBits;
5038 if (IntegerType->isUnsignedIntegerOrEnumerationType())
5039 RequiredBits = OldValue.getActiveBits();
5040 else if (OldValue.isUnsigned())
5041 RequiredBits = OldValue.getActiveBits() + 1;
5043 RequiredBits = OldValue.getMinSignedBits();
5044 if (RequiredBits > AllowedBits) {
5045 Diag(Arg->getLocStart(),
5046 diag::warn_template_arg_too_large)
5047 << OldValue.toString(10) << Value.toString(10) << Param->getType()
5048 << Arg->getSourceRange();
5049 Diag(Param->getLocation(), diag::note_template_param_here);
5053 Converted = TemplateArgument(Context, Value,
5054 ParamType->isEnumeralType()
5055 ? Context.getCanonicalType(ParamType)
5060 QualType ArgType = Arg->getType();
5061 DeclAccessPair FoundResult; // temporary for ResolveOverloadedFunction
5063 // Handle pointer-to-function, reference-to-function, and
5064 // pointer-to-member-function all in (roughly) the same way.
5065 if (// -- For a non-type template-parameter of type pointer to
5066 // function, only the function-to-pointer conversion (4.3) is
5067 // applied. If the template-argument represents a set of
5068 // overloaded functions (or a pointer to such), the matching
5069 // function is selected from the set (13.4).
5070 (ParamType->isPointerType() &&
5071 ParamType->getAs<PointerType>()->getPointeeType()->isFunctionType()) ||
5072 // -- For a non-type template-parameter of type reference to
5073 // function, no conversions apply. If the template-argument
5074 // represents a set of overloaded functions, the matching
5075 // function is selected from the set (13.4).
5076 (ParamType->isReferenceType() &&
5077 ParamType->getAs<ReferenceType>()->getPointeeType()->isFunctionType()) ||
5078 // -- For a non-type template-parameter of type pointer to
5079 // member function, no conversions apply. If the
5080 // template-argument represents a set of overloaded member
5081 // functions, the matching member function is selected from
5083 (ParamType->isMemberPointerType() &&
5084 ParamType->getAs<MemberPointerType>()->getPointeeType()
5085 ->isFunctionType())) {
5087 if (Arg->getType() == Context.OverloadTy) {
5088 if (FunctionDecl *Fn = ResolveAddressOfOverloadedFunction(Arg, ParamType,
5091 if (DiagnoseUseOfDecl(Fn, Arg->getLocStart()))
5094 Arg = FixOverloadedFunctionReference(Arg, FoundResult, Fn);
5095 ArgType = Arg->getType();
5100 if (!ParamType->isMemberPointerType()) {
5101 if (CheckTemplateArgumentAddressOfObjectOrFunction(*this, Param,
5108 if (CheckTemplateArgumentPointerToMember(*this, Param, ParamType, Arg,
5114 if (ParamType->isPointerType()) {
5115 // -- for a non-type template-parameter of type pointer to
5116 // object, qualification conversions (4.4) and the
5117 // array-to-pointer conversion (4.2) are applied.
5118 // C++0x also allows a value of std::nullptr_t.
5119 assert(ParamType->getPointeeType()->isIncompleteOrObjectType() &&
5120 "Only object pointers allowed here");
5122 if (CheckTemplateArgumentAddressOfObjectOrFunction(*this, Param,
5129 if (const ReferenceType *ParamRefType = ParamType->getAs<ReferenceType>()) {
5130 // -- For a non-type template-parameter of type reference to
5131 // object, no conversions apply. The type referred to by the
5132 // reference may be more cv-qualified than the (otherwise
5133 // identical) type of the template-argument. The
5134 // template-parameter is bound directly to the
5135 // template-argument, which must be an lvalue.
5136 assert(ParamRefType->getPointeeType()->isIncompleteOrObjectType() &&
5137 "Only object references allowed here");
5139 if (Arg->getType() == Context.OverloadTy) {
5140 if (FunctionDecl *Fn = ResolveAddressOfOverloadedFunction(Arg,
5141 ParamRefType->getPointeeType(),
5144 if (DiagnoseUseOfDecl(Fn, Arg->getLocStart()))
5147 Arg = FixOverloadedFunctionReference(Arg, FoundResult, Fn);
5148 ArgType = Arg->getType();
5153 if (CheckTemplateArgumentAddressOfObjectOrFunction(*this, Param,
5160 // Deal with parameters of type std::nullptr_t.
5161 if (ParamType->isNullPtrType()) {
5162 if (Arg->isTypeDependent() || Arg->isValueDependent()) {
5163 Converted = TemplateArgument(Arg);
5167 switch (isNullPointerValueTemplateArgument(*this, Param, ParamType, Arg)) {
5168 case NPV_NotNullPointer:
5169 Diag(Arg->getExprLoc(), diag::err_template_arg_not_convertible)
5170 << Arg->getType() << ParamType;
5171 Diag(Param->getLocation(), diag::note_template_param_here);
5177 case NPV_NullPointer:
5178 Diag(Arg->getExprLoc(), diag::warn_cxx98_compat_template_arg_null);
5179 Converted = TemplateArgument(Context.getCanonicalType(ParamType),
5185 // -- For a non-type template-parameter of type pointer to data
5186 // member, qualification conversions (4.4) are applied.
5187 assert(ParamType->isMemberPointerType() && "Only pointers to members remain");
5189 if (CheckTemplateArgumentPointerToMember(*this, Param, ParamType, Arg,
5195 /// \brief Check a template argument against its corresponding
5196 /// template template parameter.
5198 /// This routine implements the semantics of C++ [temp.arg.template].
5199 /// It returns true if an error occurred, and false otherwise.
5200 bool Sema::CheckTemplateArgument(TemplateTemplateParmDecl *Param,
5201 TemplateArgumentLoc &Arg,
5202 unsigned ArgumentPackIndex) {
5203 TemplateName Name = Arg.getArgument().getAsTemplateOrTemplatePattern();
5204 TemplateDecl *Template = Name.getAsTemplateDecl();
5206 // Any dependent template name is fine.
5207 assert(Name.isDependent() && "Non-dependent template isn't a declaration?");
5211 // C++0x [temp.arg.template]p1:
5212 // A template-argument for a template template-parameter shall be
5213 // the name of a class template or an alias template, expressed as an
5214 // id-expression. When the template-argument names a class template, only
5215 // primary class templates are considered when matching the
5216 // template template argument with the corresponding parameter;
5217 // partial specializations are not considered even if their
5218 // parameter lists match that of the template template parameter.
5220 // Note that we also allow template template parameters here, which
5221 // will happen when we are dealing with, e.g., class template
5222 // partial specializations.
5223 if (!isa<ClassTemplateDecl>(Template) &&
5224 !isa<TemplateTemplateParmDecl>(Template) &&
5225 !isa<TypeAliasTemplateDecl>(Template)) {
5226 assert(isa<FunctionTemplateDecl>(Template) &&
5227 "Only function templates are possible here");
5228 Diag(Arg.getLocation(), diag::err_template_arg_not_class_template);
5229 Diag(Template->getLocation(), diag::note_template_arg_refers_here_func)
5233 TemplateParameterList *Params = Param->getTemplateParameters();
5234 if (Param->isExpandedParameterPack())
5235 Params = Param->getExpansionTemplateParameters(ArgumentPackIndex);
5237 return !TemplateParameterListsAreEqual(Template->getTemplateParameters(),
5240 TPL_TemplateTemplateArgumentMatch,
5244 /// \brief Given a non-type template argument that refers to a
5245 /// declaration and the type of its corresponding non-type template
5246 /// parameter, produce an expression that properly refers to that
5249 Sema::BuildExpressionFromDeclTemplateArgument(const TemplateArgument &Arg,
5251 SourceLocation Loc) {
5252 // C++ [temp.param]p8:
5254 // A non-type template-parameter of type "array of T" or
5255 // "function returning T" is adjusted to be of type "pointer to
5256 // T" or "pointer to function returning T", respectively.
5257 if (ParamType->isArrayType())
5258 ParamType = Context.getArrayDecayedType(ParamType);
5259 else if (ParamType->isFunctionType())
5260 ParamType = Context.getPointerType(ParamType);
5262 // For a NULL non-type template argument, return nullptr casted to the
5263 // parameter's type.
5264 if (Arg.getKind() == TemplateArgument::NullPtr) {
5265 return ImpCastExprToType(
5266 new (Context) CXXNullPtrLiteralExpr(Context.NullPtrTy, Loc),
5268 ParamType->getAs<MemberPointerType>()
5269 ? CK_NullToMemberPointer
5270 : CK_NullToPointer);
5272 assert(Arg.getKind() == TemplateArgument::Declaration &&
5273 "Only declaration template arguments permitted here");
5275 ValueDecl *VD = cast<ValueDecl>(Arg.getAsDecl());
5277 if (VD->getDeclContext()->isRecord() &&
5278 (isa<CXXMethodDecl>(VD) || isa<FieldDecl>(VD) ||
5279 isa<IndirectFieldDecl>(VD))) {
5280 // If the value is a class member, we might have a pointer-to-member.
5281 // Determine whether the non-type template template parameter is of
5282 // pointer-to-member type. If so, we need to build an appropriate
5283 // expression for a pointer-to-member, since a "normal" DeclRefExpr
5284 // would refer to the member itself.
5285 if (ParamType->isMemberPointerType()) {
5287 = Context.getTypeDeclType(cast<RecordDecl>(VD->getDeclContext()));
5288 NestedNameSpecifier *Qualifier
5289 = NestedNameSpecifier::Create(Context, nullptr, false,
5290 ClassType.getTypePtr());
5292 SS.MakeTrivial(Context, Qualifier, Loc);
5294 // The actual value-ness of this is unimportant, but for
5295 // internal consistency's sake, references to instance methods
5297 ExprValueKind VK = VK_LValue;
5298 if (isa<CXXMethodDecl>(VD) && cast<CXXMethodDecl>(VD)->isInstance())
5301 ExprResult RefExpr = BuildDeclRefExpr(VD,
5302 VD->getType().getNonReferenceType(),
5306 if (RefExpr.isInvalid())
5309 RefExpr = CreateBuiltinUnaryOp(Loc, UO_AddrOf, RefExpr.get());
5311 // We might need to perform a trailing qualification conversion, since
5312 // the element type on the parameter could be more qualified than the
5313 // element type in the expression we constructed.
5314 bool ObjCLifetimeConversion;
5315 if (IsQualificationConversion(((Expr*) RefExpr.get())->getType(),
5316 ParamType.getUnqualifiedType(), false,
5317 ObjCLifetimeConversion))
5318 RefExpr = ImpCastExprToType(RefExpr.get(), ParamType.getUnqualifiedType(), CK_NoOp);
5320 assert(!RefExpr.isInvalid() &&
5321 Context.hasSameType(((Expr*) RefExpr.get())->getType(),
5322 ParamType.getUnqualifiedType()));
5327 QualType T = VD->getType().getNonReferenceType();
5329 if (ParamType->isPointerType()) {
5330 // When the non-type template parameter is a pointer, take the
5331 // address of the declaration.
5332 ExprResult RefExpr = BuildDeclRefExpr(VD, T, VK_LValue, Loc);
5333 if (RefExpr.isInvalid())
5336 if (T->isFunctionType() || T->isArrayType()) {
5337 // Decay functions and arrays.
5338 RefExpr = DefaultFunctionArrayConversion(RefExpr.get());
5339 if (RefExpr.isInvalid())
5345 // Take the address of everything else
5346 return CreateBuiltinUnaryOp(Loc, UO_AddrOf, RefExpr.get());
5349 ExprValueKind VK = VK_RValue;
5351 // If the non-type template parameter has reference type, qualify the
5352 // resulting declaration reference with the extra qualifiers on the
5353 // type that the reference refers to.
5354 if (const ReferenceType *TargetRef = ParamType->getAs<ReferenceType>()) {
5356 T = Context.getQualifiedType(T,
5357 TargetRef->getPointeeType().getQualifiers());
5358 } else if (isa<FunctionDecl>(VD)) {
5359 // References to functions are always lvalues.
5363 return BuildDeclRefExpr(VD, T, VK, Loc);
5366 /// \brief Construct a new expression that refers to the given
5367 /// integral template argument with the given source-location
5370 /// This routine takes care of the mapping from an integral template
5371 /// argument (which may have any integral type) to the appropriate
5374 Sema::BuildExpressionFromIntegralTemplateArgument(const TemplateArgument &Arg,
5375 SourceLocation Loc) {
5376 assert(Arg.getKind() == TemplateArgument::Integral &&
5377 "Operation is only valid for integral template arguments");
5378 QualType OrigT = Arg.getIntegralType();
5380 // If this is an enum type that we're instantiating, we need to use an integer
5381 // type the same size as the enumerator. We don't want to build an
5382 // IntegerLiteral with enum type. The integer type of an enum type can be of
5383 // any integral type with C++11 enum classes, make sure we create the right
5384 // type of literal for it.
5386 if (const EnumType *ET = OrigT->getAs<EnumType>())
5387 T = ET->getDecl()->getIntegerType();
5390 if (T->isAnyCharacterType()) {
5391 CharacterLiteral::CharacterKind Kind;
5392 if (T->isWideCharType())
5393 Kind = CharacterLiteral::Wide;
5394 else if (T->isChar16Type())
5395 Kind = CharacterLiteral::UTF16;
5396 else if (T->isChar32Type())
5397 Kind = CharacterLiteral::UTF32;
5399 Kind = CharacterLiteral::Ascii;
5401 E = new (Context) CharacterLiteral(Arg.getAsIntegral().getZExtValue(),
5403 } else if (T->isBooleanType()) {
5404 E = new (Context) CXXBoolLiteralExpr(Arg.getAsIntegral().getBoolValue(),
5406 } else if (T->isNullPtrType()) {
5407 E = new (Context) CXXNullPtrLiteralExpr(Context.NullPtrTy, Loc);
5409 E = IntegerLiteral::Create(Context, Arg.getAsIntegral(), T, Loc);
5412 if (OrigT->isEnumeralType()) {
5413 // FIXME: This is a hack. We need a better way to handle substituted
5414 // non-type template parameters.
5415 E = CStyleCastExpr::Create(Context, OrigT, VK_RValue, CK_IntegralCast, E,
5417 Context.getTrivialTypeSourceInfo(OrigT, Loc),
5424 /// \brief Match two template parameters within template parameter lists.
5425 static bool MatchTemplateParameterKind(Sema &S, NamedDecl *New, NamedDecl *Old,
5427 Sema::TemplateParameterListEqualKind Kind,
5428 SourceLocation TemplateArgLoc) {
5429 // Check the actual kind (type, non-type, template).
5430 if (Old->getKind() != New->getKind()) {
5432 unsigned NextDiag = diag::err_template_param_different_kind;
5433 if (TemplateArgLoc.isValid()) {
5434 S.Diag(TemplateArgLoc, diag::err_template_arg_template_params_mismatch);
5435 NextDiag = diag::note_template_param_different_kind;
5437 S.Diag(New->getLocation(), NextDiag)
5438 << (Kind != Sema::TPL_TemplateMatch);
5439 S.Diag(Old->getLocation(), diag::note_template_prev_declaration)
5440 << (Kind != Sema::TPL_TemplateMatch);
5446 // Check that both are parameter packs are neither are parameter packs.
5447 // However, if we are matching a template template argument to a
5448 // template template parameter, the template template parameter can have
5449 // a parameter pack where the template template argument does not.
5450 if (Old->isTemplateParameterPack() != New->isTemplateParameterPack() &&
5451 !(Kind == Sema::TPL_TemplateTemplateArgumentMatch &&
5452 Old->isTemplateParameterPack())) {
5454 unsigned NextDiag = diag::err_template_parameter_pack_non_pack;
5455 if (TemplateArgLoc.isValid()) {
5456 S.Diag(TemplateArgLoc,
5457 diag::err_template_arg_template_params_mismatch);
5458 NextDiag = diag::note_template_parameter_pack_non_pack;
5461 unsigned ParamKind = isa<TemplateTypeParmDecl>(New)? 0
5462 : isa<NonTypeTemplateParmDecl>(New)? 1
5464 S.Diag(New->getLocation(), NextDiag)
5465 << ParamKind << New->isParameterPack();
5466 S.Diag(Old->getLocation(), diag::note_template_parameter_pack_here)
5467 << ParamKind << Old->isParameterPack();
5473 // For non-type template parameters, check the type of the parameter.
5474 if (NonTypeTemplateParmDecl *OldNTTP
5475 = dyn_cast<NonTypeTemplateParmDecl>(Old)) {
5476 NonTypeTemplateParmDecl *NewNTTP = cast<NonTypeTemplateParmDecl>(New);
5478 // If we are matching a template template argument to a template
5479 // template parameter and one of the non-type template parameter types
5480 // is dependent, then we must wait until template instantiation time
5481 // to actually compare the arguments.
5482 if (Kind == Sema::TPL_TemplateTemplateArgumentMatch &&
5483 (OldNTTP->getType()->isDependentType() ||
5484 NewNTTP->getType()->isDependentType()))
5487 if (!S.Context.hasSameType(OldNTTP->getType(), NewNTTP->getType())) {
5489 unsigned NextDiag = diag::err_template_nontype_parm_different_type;
5490 if (TemplateArgLoc.isValid()) {
5491 S.Diag(TemplateArgLoc,
5492 diag::err_template_arg_template_params_mismatch);
5493 NextDiag = diag::note_template_nontype_parm_different_type;
5495 S.Diag(NewNTTP->getLocation(), NextDiag)
5496 << NewNTTP->getType()
5497 << (Kind != Sema::TPL_TemplateMatch);
5498 S.Diag(OldNTTP->getLocation(),
5499 diag::note_template_nontype_parm_prev_declaration)
5500 << OldNTTP->getType();
5509 // For template template parameters, check the template parameter types.
5510 // The template parameter lists of template template
5511 // parameters must agree.
5512 if (TemplateTemplateParmDecl *OldTTP
5513 = dyn_cast<TemplateTemplateParmDecl>(Old)) {
5514 TemplateTemplateParmDecl *NewTTP = cast<TemplateTemplateParmDecl>(New);
5515 return S.TemplateParameterListsAreEqual(NewTTP->getTemplateParameters(),
5516 OldTTP->getTemplateParameters(),
5518 (Kind == Sema::TPL_TemplateMatch
5519 ? Sema::TPL_TemplateTemplateParmMatch
5527 /// \brief Diagnose a known arity mismatch when comparing template argument
5530 void DiagnoseTemplateParameterListArityMismatch(Sema &S,
5531 TemplateParameterList *New,
5532 TemplateParameterList *Old,
5533 Sema::TemplateParameterListEqualKind Kind,
5534 SourceLocation TemplateArgLoc) {
5535 unsigned NextDiag = diag::err_template_param_list_different_arity;
5536 if (TemplateArgLoc.isValid()) {
5537 S.Diag(TemplateArgLoc, diag::err_template_arg_template_params_mismatch);
5538 NextDiag = diag::note_template_param_list_different_arity;
5540 S.Diag(New->getTemplateLoc(), NextDiag)
5541 << (New->size() > Old->size())
5542 << (Kind != Sema::TPL_TemplateMatch)
5543 << SourceRange(New->getTemplateLoc(), New->getRAngleLoc());
5544 S.Diag(Old->getTemplateLoc(), diag::note_template_prev_declaration)
5545 << (Kind != Sema::TPL_TemplateMatch)
5546 << SourceRange(Old->getTemplateLoc(), Old->getRAngleLoc());
5549 /// \brief Determine whether the given template parameter lists are
5552 /// \param New The new template parameter list, typically written in the
5553 /// source code as part of a new template declaration.
5555 /// \param Old The old template parameter list, typically found via
5556 /// name lookup of the template declared with this template parameter
5559 /// \param Complain If true, this routine will produce a diagnostic if
5560 /// the template parameter lists are not equivalent.
5562 /// \param Kind describes how we are to match the template parameter lists.
5564 /// \param TemplateArgLoc If this source location is valid, then we
5565 /// are actually checking the template parameter list of a template
5566 /// argument (New) against the template parameter list of its
5567 /// corresponding template template parameter (Old). We produce
5568 /// slightly different diagnostics in this scenario.
5570 /// \returns True if the template parameter lists are equal, false
5573 Sema::TemplateParameterListsAreEqual(TemplateParameterList *New,
5574 TemplateParameterList *Old,
5576 TemplateParameterListEqualKind Kind,
5577 SourceLocation TemplateArgLoc) {
5578 if (Old->size() != New->size() && Kind != TPL_TemplateTemplateArgumentMatch) {
5580 DiagnoseTemplateParameterListArityMismatch(*this, New, Old, Kind,
5586 // C++0x [temp.arg.template]p3:
5587 // A template-argument matches a template template-parameter (call it P)
5588 // when each of the template parameters in the template-parameter-list of
5589 // the template-argument's corresponding class template or alias template
5590 // (call it A) matches the corresponding template parameter in the
5591 // template-parameter-list of P. [...]
5592 TemplateParameterList::iterator NewParm = New->begin();
5593 TemplateParameterList::iterator NewParmEnd = New->end();
5594 for (TemplateParameterList::iterator OldParm = Old->begin(),
5595 OldParmEnd = Old->end();
5596 OldParm != OldParmEnd; ++OldParm) {
5597 if (Kind != TPL_TemplateTemplateArgumentMatch ||
5598 !(*OldParm)->isTemplateParameterPack()) {
5599 if (NewParm == NewParmEnd) {
5601 DiagnoseTemplateParameterListArityMismatch(*this, New, Old, Kind,
5607 if (!MatchTemplateParameterKind(*this, *NewParm, *OldParm, Complain,
5608 Kind, TemplateArgLoc))
5615 // C++0x [temp.arg.template]p3:
5616 // [...] When P's template- parameter-list contains a template parameter
5617 // pack (14.5.3), the template parameter pack will match zero or more
5618 // template parameters or template parameter packs in the
5619 // template-parameter-list of A with the same type and form as the
5620 // template parameter pack in P (ignoring whether those template
5621 // parameters are template parameter packs).
5622 for (; NewParm != NewParmEnd; ++NewParm) {
5623 if (!MatchTemplateParameterKind(*this, *NewParm, *OldParm, Complain,
5624 Kind, TemplateArgLoc))
5629 // Make sure we exhausted all of the arguments.
5630 if (NewParm != NewParmEnd) {
5632 DiagnoseTemplateParameterListArityMismatch(*this, New, Old, Kind,
5641 /// \brief Check whether a template can be declared within this scope.
5643 /// If the template declaration is valid in this scope, returns
5644 /// false. Otherwise, issues a diagnostic and returns true.
5646 Sema::CheckTemplateDeclScope(Scope *S, TemplateParameterList *TemplateParams) {
5650 // Find the nearest enclosing declaration scope.
5651 while ((S->getFlags() & Scope::DeclScope) == 0 ||
5652 (S->getFlags() & Scope::TemplateParamScope) != 0)
5656 // A template [...] shall not have C linkage.
5657 DeclContext *Ctx = S->getEntity();
5658 if (Ctx && Ctx->isExternCContext())
5659 return Diag(TemplateParams->getTemplateLoc(), diag::err_template_linkage)
5660 << TemplateParams->getSourceRange();
5662 while (Ctx && isa<LinkageSpecDecl>(Ctx))
5663 Ctx = Ctx->getParent();
5666 // A template-declaration can appear only as a namespace scope or
5667 // class scope declaration.
5669 if (Ctx->isFileContext())
5671 if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(Ctx)) {
5672 // C++ [temp.mem]p2:
5673 // A local class shall not have member templates.
5674 if (RD->isLocalClass())
5675 return Diag(TemplateParams->getTemplateLoc(),
5676 diag::err_template_inside_local_class)
5677 << TemplateParams->getSourceRange();
5683 return Diag(TemplateParams->getTemplateLoc(),
5684 diag::err_template_outside_namespace_or_class_scope)
5685 << TemplateParams->getSourceRange();
5688 /// \brief Determine what kind of template specialization the given declaration
5690 static TemplateSpecializationKind getTemplateSpecializationKind(Decl *D) {
5692 return TSK_Undeclared;
5694 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(D))
5695 return Record->getTemplateSpecializationKind();
5696 if (FunctionDecl *Function = dyn_cast<FunctionDecl>(D))
5697 return Function->getTemplateSpecializationKind();
5698 if (VarDecl *Var = dyn_cast<VarDecl>(D))
5699 return Var->getTemplateSpecializationKind();
5701 return TSK_Undeclared;
5704 /// \brief Check whether a specialization is well-formed in the current
5707 /// This routine determines whether a template specialization can be declared
5708 /// in the current context (C++ [temp.expl.spec]p2).
5710 /// \param S the semantic analysis object for which this check is being
5713 /// \param Specialized the entity being specialized or instantiated, which
5714 /// may be a kind of template (class template, function template, etc.) or
5715 /// a member of a class template (member function, static data member,
5718 /// \param PrevDecl the previous declaration of this entity, if any.
5720 /// \param Loc the location of the explicit specialization or instantiation of
5723 /// \param IsPartialSpecialization whether this is a partial specialization of
5724 /// a class template.
5726 /// \returns true if there was an error that we cannot recover from, false
5728 static bool CheckTemplateSpecializationScope(Sema &S,
5729 NamedDecl *Specialized,
5730 NamedDecl *PrevDecl,
5732 bool IsPartialSpecialization) {
5733 // Keep these "kind" numbers in sync with the %select statements in the
5734 // various diagnostics emitted by this routine.
5736 if (isa<ClassTemplateDecl>(Specialized))
5737 EntityKind = IsPartialSpecialization? 1 : 0;
5738 else if (isa<VarTemplateDecl>(Specialized))
5739 EntityKind = IsPartialSpecialization ? 3 : 2;
5740 else if (isa<FunctionTemplateDecl>(Specialized))
5742 else if (isa<CXXMethodDecl>(Specialized))
5744 else if (isa<VarDecl>(Specialized))
5746 else if (isa<RecordDecl>(Specialized))
5748 else if (isa<EnumDecl>(Specialized) && S.getLangOpts().CPlusPlus11)
5751 S.Diag(Loc, diag::err_template_spec_unknown_kind)
5752 << S.getLangOpts().CPlusPlus11;
5753 S.Diag(Specialized->getLocation(), diag::note_specialized_entity);
5757 // C++ [temp.expl.spec]p2:
5758 // An explicit specialization shall be declared in the namespace
5759 // of which the template is a member, or, for member templates, in
5760 // the namespace of which the enclosing class or enclosing class
5761 // template is a member. An explicit specialization of a member
5762 // function, member class or static data member of a class
5763 // template shall be declared in the namespace of which the class
5764 // template is a member. Such a declaration may also be a
5765 // definition. If the declaration is not a definition, the
5766 // specialization may be defined later in the name- space in which
5767 // the explicit specialization was declared, or in a namespace
5768 // that encloses the one in which the explicit specialization was
5770 if (S.CurContext->getRedeclContext()->isFunctionOrMethod()) {
5771 S.Diag(Loc, diag::err_template_spec_decl_function_scope)
5776 if (S.CurContext->isRecord() && !IsPartialSpecialization) {
5777 if (S.getLangOpts().MicrosoftExt) {
5778 // Do not warn for class scope explicit specialization during
5779 // instantiation, warning was already emitted during pattern
5780 // semantic analysis.
5781 if (!S.ActiveTemplateInstantiations.size())
5782 S.Diag(Loc, diag::ext_function_specialization_in_class)
5785 S.Diag(Loc, diag::err_template_spec_decl_class_scope)
5791 if (S.CurContext->isRecord() &&
5792 !S.CurContext->Equals(Specialized->getDeclContext())) {
5793 // Make sure that we're specializing in the right record context.
5794 // Otherwise, things can go horribly wrong.
5795 S.Diag(Loc, diag::err_template_spec_decl_class_scope)
5800 // C++ [temp.class.spec]p6:
5801 // A class template partial specialization may be declared or redeclared
5802 // in any namespace scope in which its definition may be defined (14.5.1
5804 DeclContext *SpecializedContext
5805 = Specialized->getDeclContext()->getEnclosingNamespaceContext();
5806 DeclContext *DC = S.CurContext->getEnclosingNamespaceContext();
5808 // Make sure that this redeclaration (or definition) occurs in an enclosing
5810 // Note that HandleDeclarator() performs this check for explicit
5811 // specializations of function templates, static data members, and member
5812 // functions, so we skip the check here for those kinds of entities.
5813 // FIXME: HandleDeclarator's diagnostics aren't quite as good, though.
5814 // Should we refactor that check, so that it occurs later?
5815 if (!DC->Encloses(SpecializedContext) &&
5816 !(isa<FunctionTemplateDecl>(Specialized) ||
5817 isa<FunctionDecl>(Specialized) ||
5818 isa<VarTemplateDecl>(Specialized) ||
5819 isa<VarDecl>(Specialized))) {
5820 if (isa<TranslationUnitDecl>(SpecializedContext))
5821 S.Diag(Loc, diag::err_template_spec_redecl_global_scope)
5822 << EntityKind << Specialized;
5823 else if (isa<NamespaceDecl>(SpecializedContext))
5824 S.Diag(Loc, diag::err_template_spec_redecl_out_of_scope)
5825 << EntityKind << Specialized
5826 << cast<NamedDecl>(SpecializedContext);
5828 llvm_unreachable("unexpected namespace context for specialization");
5830 S.Diag(Specialized->getLocation(), diag::note_specialized_entity);
5831 } else if ((!PrevDecl ||
5832 getTemplateSpecializationKind(PrevDecl) == TSK_Undeclared ||
5833 getTemplateSpecializationKind(PrevDecl) ==
5834 TSK_ImplicitInstantiation)) {
5835 // C++ [temp.exp.spec]p2:
5836 // An explicit specialization shall be declared in the namespace of which
5837 // the template is a member, or, for member templates, in the namespace
5838 // of which the enclosing class or enclosing class template is a member.
5839 // An explicit specialization of a member function, member class or
5840 // static data member of a class template shall be declared in the
5841 // namespace of which the class template is a member.
5843 // C++11 [temp.expl.spec]p2:
5844 // An explicit specialization shall be declared in a namespace enclosing
5845 // the specialized template.
5846 // C++11 [temp.explicit]p3:
5847 // An explicit instantiation shall appear in an enclosing namespace of its
5849 if (!DC->InEnclosingNamespaceSetOf(SpecializedContext)) {
5850 bool IsCPlusPlus11Extension = DC->Encloses(SpecializedContext);
5851 if (isa<TranslationUnitDecl>(SpecializedContext)) {
5852 assert(!IsCPlusPlus11Extension &&
5853 "DC encloses TU but isn't in enclosing namespace set");
5854 S.Diag(Loc, diag::err_template_spec_decl_out_of_scope_global)
5855 << EntityKind << Specialized;
5856 } else if (isa<NamespaceDecl>(SpecializedContext)) {
5858 if (!IsCPlusPlus11Extension)
5859 Diag = diag::err_template_spec_decl_out_of_scope;
5860 else if (!S.getLangOpts().CPlusPlus11)
5861 Diag = diag::ext_template_spec_decl_out_of_scope;
5863 Diag = diag::warn_cxx98_compat_template_spec_decl_out_of_scope;
5865 << EntityKind << Specialized << cast<NamedDecl>(SpecializedContext);
5868 S.Diag(Specialized->getLocation(), diag::note_specialized_entity);
5875 static SourceRange findTemplateParameter(unsigned Depth, Expr *E) {
5876 if (!E->isInstantiationDependent())
5877 return SourceLocation();
5878 DependencyChecker Checker(Depth);
5879 Checker.TraverseStmt(E);
5880 if (Checker.Match && Checker.MatchLoc.isInvalid())
5881 return E->getSourceRange();
5882 return Checker.MatchLoc;
5885 static SourceRange findTemplateParameter(unsigned Depth, TypeLoc TL) {
5886 if (!TL.getType()->isDependentType())
5887 return SourceLocation();
5888 DependencyChecker Checker(Depth);
5889 Checker.TraverseTypeLoc(TL);
5890 if (Checker.Match && Checker.MatchLoc.isInvalid())
5891 return TL.getSourceRange();
5892 return Checker.MatchLoc;
5895 /// \brief Subroutine of Sema::CheckTemplatePartialSpecializationArgs
5896 /// that checks non-type template partial specialization arguments.
5897 static bool CheckNonTypeTemplatePartialSpecializationArgs(
5898 Sema &S, SourceLocation TemplateNameLoc, NonTypeTemplateParmDecl *Param,
5899 const TemplateArgument *Args, unsigned NumArgs, bool IsDefaultArgument) {
5900 for (unsigned I = 0; I != NumArgs; ++I) {
5901 if (Args[I].getKind() == TemplateArgument::Pack) {
5902 if (CheckNonTypeTemplatePartialSpecializationArgs(
5903 S, TemplateNameLoc, Param, Args[I].pack_begin(),
5904 Args[I].pack_size(), IsDefaultArgument))
5910 if (Args[I].getKind() != TemplateArgument::Expression)
5913 Expr *ArgExpr = Args[I].getAsExpr();
5915 // We can have a pack expansion of any of the bullets below.
5916 if (PackExpansionExpr *Expansion = dyn_cast<PackExpansionExpr>(ArgExpr))
5917 ArgExpr = Expansion->getPattern();
5919 // Strip off any implicit casts we added as part of type checking.
5920 while (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(ArgExpr))
5921 ArgExpr = ICE->getSubExpr();
5923 // C++ [temp.class.spec]p8:
5924 // A non-type argument is non-specialized if it is the name of a
5925 // non-type parameter. All other non-type arguments are
5928 // Below, we check the two conditions that only apply to
5929 // specialized non-type arguments, so skip any non-specialized
5931 if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(ArgExpr))
5932 if (isa<NonTypeTemplateParmDecl>(DRE->getDecl()))
5935 // C++ [temp.class.spec]p9:
5936 // Within the argument list of a class template partial
5937 // specialization, the following restrictions apply:
5938 // -- A partially specialized non-type argument expression
5939 // shall not involve a template parameter of the partial
5940 // specialization except when the argument expression is a
5941 // simple identifier.
5942 SourceRange ParamUseRange =
5943 findTemplateParameter(Param->getDepth(), ArgExpr);
5944 if (ParamUseRange.isValid()) {
5945 if (IsDefaultArgument) {
5946 S.Diag(TemplateNameLoc,
5947 diag::err_dependent_non_type_arg_in_partial_spec);
5948 S.Diag(ParamUseRange.getBegin(),
5949 diag::note_dependent_non_type_default_arg_in_partial_spec)
5952 S.Diag(ParamUseRange.getBegin(),
5953 diag::err_dependent_non_type_arg_in_partial_spec)
5959 // -- The type of a template parameter corresponding to a
5960 // specialized non-type argument shall not be dependent on a
5961 // parameter of the specialization.
5963 // FIXME: We need to delay this check until instantiation in some cases:
5965 // template<template<typename> class X> struct A {
5966 // template<typename T, X<T> N> struct B;
5967 // template<typename T> struct B<T, 0>;
5969 // template<typename> using X = int;
5970 // A<X>::B<int, 0> b;
5971 ParamUseRange = findTemplateParameter(
5972 Param->getDepth(), Param->getTypeSourceInfo()->getTypeLoc());
5973 if (ParamUseRange.isValid()) {
5974 S.Diag(IsDefaultArgument ? TemplateNameLoc : ArgExpr->getLocStart(),
5975 diag::err_dependent_typed_non_type_arg_in_partial_spec)
5976 << Param->getType() << ParamUseRange;
5977 S.Diag(Param->getLocation(), diag::note_template_param_here)
5978 << (IsDefaultArgument ? ParamUseRange : SourceRange());
5986 /// \brief Check the non-type template arguments of a class template
5987 /// partial specialization according to C++ [temp.class.spec]p9.
5989 /// \param TemplateNameLoc the location of the template name.
5990 /// \param TemplateParams the template parameters of the primary class
5992 /// \param NumExplicit the number of explicitly-specified template arguments.
5993 /// \param TemplateArgs the template arguments of the class template
5994 /// partial specialization.
5996 /// \returns \c true if there was an error, \c false otherwise.
5997 static bool CheckTemplatePartialSpecializationArgs(
5998 Sema &S, SourceLocation TemplateNameLoc,
5999 TemplateParameterList *TemplateParams, unsigned NumExplicit,
6000 SmallVectorImpl<TemplateArgument> &TemplateArgs) {
6001 const TemplateArgument *ArgList = TemplateArgs.data();
6003 for (unsigned I = 0, N = TemplateParams->size(); I != N; ++I) {
6004 NonTypeTemplateParmDecl *Param
6005 = dyn_cast<NonTypeTemplateParmDecl>(TemplateParams->getParam(I));
6009 if (CheckNonTypeTemplatePartialSpecializationArgs(
6010 S, TemplateNameLoc, Param, &ArgList[I], 1, I >= NumExplicit))
6018 Sema::ActOnClassTemplateSpecialization(Scope *S, unsigned TagSpec,
6020 SourceLocation KWLoc,
6021 SourceLocation ModulePrivateLoc,
6022 TemplateIdAnnotation &TemplateId,
6023 AttributeList *Attr,
6024 MultiTemplateParamsArg TemplateParameterLists) {
6025 assert(TUK != TUK_Reference && "References are not specializations");
6027 CXXScopeSpec &SS = TemplateId.SS;
6029 // NOTE: KWLoc is the location of the tag keyword. This will instead
6030 // store the location of the outermost template keyword in the declaration.
6031 SourceLocation TemplateKWLoc = TemplateParameterLists.size() > 0
6032 ? TemplateParameterLists[0]->getTemplateLoc() : KWLoc;
6033 SourceLocation TemplateNameLoc = TemplateId.TemplateNameLoc;
6034 SourceLocation LAngleLoc = TemplateId.LAngleLoc;
6035 SourceLocation RAngleLoc = TemplateId.RAngleLoc;
6037 // Find the class template we're specializing
6038 TemplateName Name = TemplateId.Template.get();
6039 ClassTemplateDecl *ClassTemplate
6040 = dyn_cast_or_null<ClassTemplateDecl>(Name.getAsTemplateDecl());
6042 if (!ClassTemplate) {
6043 Diag(TemplateNameLoc, diag::err_not_class_template_specialization)
6044 << (Name.getAsTemplateDecl() &&
6045 isa<TemplateTemplateParmDecl>(Name.getAsTemplateDecl()));
6049 bool isExplicitSpecialization = false;
6050 bool isPartialSpecialization = false;
6052 // Check the validity of the template headers that introduce this
6054 // FIXME: We probably shouldn't complain about these headers for
6055 // friend declarations.
6056 bool Invalid = false;
6057 TemplateParameterList *TemplateParams =
6058 MatchTemplateParametersToScopeSpecifier(
6059 KWLoc, TemplateNameLoc, SS, &TemplateId,
6060 TemplateParameterLists, TUK == TUK_Friend, isExplicitSpecialization,
6065 if (TemplateParams && TemplateParams->size() > 0) {
6066 isPartialSpecialization = true;
6068 if (TUK == TUK_Friend) {
6069 Diag(KWLoc, diag::err_partial_specialization_friend)
6070 << SourceRange(LAngleLoc, RAngleLoc);
6074 // C++ [temp.class.spec]p10:
6075 // The template parameter list of a specialization shall not
6076 // contain default template argument values.
6077 for (unsigned I = 0, N = TemplateParams->size(); I != N; ++I) {
6078 Decl *Param = TemplateParams->getParam(I);
6079 if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(Param)) {
6080 if (TTP->hasDefaultArgument()) {
6081 Diag(TTP->getDefaultArgumentLoc(),
6082 diag::err_default_arg_in_partial_spec);
6083 TTP->removeDefaultArgument();
6085 } else if (NonTypeTemplateParmDecl *NTTP
6086 = dyn_cast<NonTypeTemplateParmDecl>(Param)) {
6087 if (Expr *DefArg = NTTP->getDefaultArgument()) {
6088 Diag(NTTP->getDefaultArgumentLoc(),
6089 diag::err_default_arg_in_partial_spec)
6090 << DefArg->getSourceRange();
6091 NTTP->removeDefaultArgument();
6094 TemplateTemplateParmDecl *TTP = cast<TemplateTemplateParmDecl>(Param);
6095 if (TTP->hasDefaultArgument()) {
6096 Diag(TTP->getDefaultArgument().getLocation(),
6097 diag::err_default_arg_in_partial_spec)
6098 << TTP->getDefaultArgument().getSourceRange();
6099 TTP->removeDefaultArgument();
6103 } else if (TemplateParams) {
6104 if (TUK == TUK_Friend)
6105 Diag(KWLoc, diag::err_template_spec_friend)
6106 << FixItHint::CreateRemoval(
6107 SourceRange(TemplateParams->getTemplateLoc(),
6108 TemplateParams->getRAngleLoc()))
6109 << SourceRange(LAngleLoc, RAngleLoc);
6111 isExplicitSpecialization = true;
6113 assert(TUK == TUK_Friend && "should have a 'template<>' for this decl");
6116 // Check that the specialization uses the same tag kind as the
6117 // original template.
6118 TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec);
6119 assert(Kind != TTK_Enum && "Invalid enum tag in class template spec!");
6120 if (!isAcceptableTagRedeclaration(ClassTemplate->getTemplatedDecl(),
6121 Kind, TUK == TUK_Definition, KWLoc,
6122 *ClassTemplate->getIdentifier())) {
6123 Diag(KWLoc, diag::err_use_with_wrong_tag)
6125 << FixItHint::CreateReplacement(KWLoc,
6126 ClassTemplate->getTemplatedDecl()->getKindName());
6127 Diag(ClassTemplate->getTemplatedDecl()->getLocation(),
6128 diag::note_previous_use);
6129 Kind = ClassTemplate->getTemplatedDecl()->getTagKind();
6132 // Translate the parser's template argument list in our AST format.
6133 TemplateArgumentListInfo TemplateArgs =
6134 makeTemplateArgumentListInfo(*this, TemplateId);
6136 // Check for unexpanded parameter packs in any of the template arguments.
6137 for (unsigned I = 0, N = TemplateArgs.size(); I != N; ++I)
6138 if (DiagnoseUnexpandedParameterPack(TemplateArgs[I],
6139 UPPC_PartialSpecialization))
6142 // Check that the template argument list is well-formed for this
6144 SmallVector<TemplateArgument, 4> Converted;
6145 if (CheckTemplateArgumentList(ClassTemplate, TemplateNameLoc,
6146 TemplateArgs, false, Converted))
6149 // Find the class template (partial) specialization declaration that
6150 // corresponds to these arguments.
6151 if (isPartialSpecialization) {
6152 if (CheckTemplatePartialSpecializationArgs(
6153 *this, TemplateNameLoc, ClassTemplate->getTemplateParameters(),
6154 TemplateArgs.size(), Converted))
6157 bool InstantiationDependent;
6158 if (!Name.isDependent() &&
6159 !TemplateSpecializationType::anyDependentTemplateArguments(
6160 TemplateArgs.getArgumentArray(),
6161 TemplateArgs.size(),
6162 InstantiationDependent)) {
6163 Diag(TemplateNameLoc, diag::err_partial_spec_fully_specialized)
6164 << ClassTemplate->getDeclName();
6165 isPartialSpecialization = false;
6169 void *InsertPos = nullptr;
6170 ClassTemplateSpecializationDecl *PrevDecl = nullptr;
6172 if (isPartialSpecialization)
6173 // FIXME: Template parameter list matters, too
6174 PrevDecl = ClassTemplate->findPartialSpecialization(Converted, InsertPos);
6176 PrevDecl = ClassTemplate->findSpecialization(Converted, InsertPos);
6178 ClassTemplateSpecializationDecl *Specialization = nullptr;
6180 // Check whether we can declare a class template specialization in
6181 // the current scope.
6182 if (TUK != TUK_Friend &&
6183 CheckTemplateSpecializationScope(*this, ClassTemplate, PrevDecl,
6185 isPartialSpecialization))
6188 // The canonical type
6190 if (isPartialSpecialization) {
6191 // Build the canonical type that describes the converted template
6192 // arguments of the class template partial specialization.
6193 TemplateName CanonTemplate = Context.getCanonicalTemplateName(Name);
6194 CanonType = Context.getTemplateSpecializationType(CanonTemplate,
6198 if (Context.hasSameType(CanonType,
6199 ClassTemplate->getInjectedClassNameSpecialization())) {
6200 // C++ [temp.class.spec]p9b3:
6202 // -- The argument list of the specialization shall not be identical
6203 // to the implicit argument list of the primary template.
6204 Diag(TemplateNameLoc, diag::err_partial_spec_args_match_primary_template)
6205 << /*class template*/0 << (TUK == TUK_Definition)
6206 << FixItHint::CreateRemoval(SourceRange(LAngleLoc, RAngleLoc));
6207 return CheckClassTemplate(S, TagSpec, TUK, KWLoc, SS,
6208 ClassTemplate->getIdentifier(),
6212 AS_none, /*ModulePrivateLoc=*/SourceLocation(),
6213 /*FriendLoc*/SourceLocation(),
6214 TemplateParameterLists.size() - 1,
6215 TemplateParameterLists.data());
6218 // Create a new class template partial specialization declaration node.
6219 ClassTemplatePartialSpecializationDecl *PrevPartial
6220 = cast_or_null<ClassTemplatePartialSpecializationDecl>(PrevDecl);
6221 ClassTemplatePartialSpecializationDecl *Partial
6222 = ClassTemplatePartialSpecializationDecl::Create(Context, Kind,
6223 ClassTemplate->getDeclContext(),
6224 KWLoc, TemplateNameLoc,
6232 SetNestedNameSpecifier(Partial, SS);
6233 if (TemplateParameterLists.size() > 1 && SS.isSet()) {
6234 Partial->setTemplateParameterListsInfo(Context,
6235 TemplateParameterLists.size() - 1,
6236 TemplateParameterLists.data());
6240 ClassTemplate->AddPartialSpecialization(Partial, InsertPos);
6241 Specialization = Partial;
6243 // If we are providing an explicit specialization of a member class
6244 // template specialization, make a note of that.
6245 if (PrevPartial && PrevPartial->getInstantiatedFromMember())
6246 PrevPartial->setMemberSpecialization();
6248 // Check that all of the template parameters of the class template
6249 // partial specialization are deducible from the template
6250 // arguments. If not, this class template partial specialization
6251 // will never be used.
6252 llvm::SmallBitVector DeducibleParams(TemplateParams->size());
6253 MarkUsedTemplateParameters(Partial->getTemplateArgs(), true,
6254 TemplateParams->getDepth(),
6257 if (!DeducibleParams.all()) {
6258 unsigned NumNonDeducible = DeducibleParams.size()-DeducibleParams.count();
6259 Diag(TemplateNameLoc, diag::warn_partial_specs_not_deducible)
6260 << /*class template*/0 << (NumNonDeducible > 1)
6261 << SourceRange(TemplateNameLoc, RAngleLoc);
6262 for (unsigned I = 0, N = DeducibleParams.size(); I != N; ++I) {
6263 if (!DeducibleParams[I]) {
6264 NamedDecl *Param = cast<NamedDecl>(TemplateParams->getParam(I));
6265 if (Param->getDeclName())
6266 Diag(Param->getLocation(),
6267 diag::note_partial_spec_unused_parameter)
6268 << Param->getDeclName();
6270 Diag(Param->getLocation(),
6271 diag::note_partial_spec_unused_parameter)
6277 // Create a new class template specialization declaration node for
6278 // this explicit specialization or friend declaration.
6280 = ClassTemplateSpecializationDecl::Create(Context, Kind,
6281 ClassTemplate->getDeclContext(),
6282 KWLoc, TemplateNameLoc,
6287 SetNestedNameSpecifier(Specialization, SS);
6288 if (TemplateParameterLists.size() > 0) {
6289 Specialization->setTemplateParameterListsInfo(Context,
6290 TemplateParameterLists.size(),
6291 TemplateParameterLists.data());
6295 ClassTemplate->AddSpecialization(Specialization, InsertPos);
6297 CanonType = Context.getTypeDeclType(Specialization);
6300 // C++ [temp.expl.spec]p6:
6301 // If a template, a member template or the member of a class template is
6302 // explicitly specialized then that specialization shall be declared
6303 // before the first use of that specialization that would cause an implicit
6304 // instantiation to take place, in every translation unit in which such a
6305 // use occurs; no diagnostic is required.
6306 if (PrevDecl && PrevDecl->getPointOfInstantiation().isValid()) {
6308 for (Decl *Prev = PrevDecl; Prev; Prev = Prev->getPreviousDecl()) {
6309 // Is there any previous explicit specialization declaration?
6310 if (getTemplateSpecializationKind(Prev) == TSK_ExplicitSpecialization) {
6317 SourceRange Range(TemplateNameLoc, RAngleLoc);
6318 Diag(TemplateNameLoc, diag::err_specialization_after_instantiation)
6319 << Context.getTypeDeclType(Specialization) << Range;
6321 Diag(PrevDecl->getPointOfInstantiation(),
6322 diag::note_instantiation_required_here)
6323 << (PrevDecl->getTemplateSpecializationKind()
6324 != TSK_ImplicitInstantiation);
6329 // If this is not a friend, note that this is an explicit specialization.
6330 if (TUK != TUK_Friend)
6331 Specialization->setSpecializationKind(TSK_ExplicitSpecialization);
6333 // Check that this isn't a redefinition of this specialization.
6334 if (TUK == TUK_Definition) {
6335 if (RecordDecl *Def = Specialization->getDefinition()) {
6336 SourceRange Range(TemplateNameLoc, RAngleLoc);
6337 Diag(TemplateNameLoc, diag::err_redefinition)
6338 << Context.getTypeDeclType(Specialization) << Range;
6339 Diag(Def->getLocation(), diag::note_previous_definition);
6340 Specialization->setInvalidDecl();
6346 ProcessDeclAttributeList(S, Specialization, Attr);
6348 // Add alignment attributes if necessary; these attributes are checked when
6349 // the ASTContext lays out the structure.
6350 if (TUK == TUK_Definition) {
6351 AddAlignmentAttributesForRecord(Specialization);
6352 AddMsStructLayoutForRecord(Specialization);
6355 if (ModulePrivateLoc.isValid())
6356 Diag(Specialization->getLocation(), diag::err_module_private_specialization)
6357 << (isPartialSpecialization? 1 : 0)
6358 << FixItHint::CreateRemoval(ModulePrivateLoc);
6360 // Build the fully-sugared type for this class template
6361 // specialization as the user wrote in the specialization
6362 // itself. This means that we'll pretty-print the type retrieved
6363 // from the specialization's declaration the way that the user
6364 // actually wrote the specialization, rather than formatting the
6365 // name based on the "canonical" representation used to store the
6366 // template arguments in the specialization.
6367 TypeSourceInfo *WrittenTy
6368 = Context.getTemplateSpecializationTypeInfo(Name, TemplateNameLoc,
6369 TemplateArgs, CanonType);
6370 if (TUK != TUK_Friend) {
6371 Specialization->setTypeAsWritten(WrittenTy);
6372 Specialization->setTemplateKeywordLoc(TemplateKWLoc);
6375 // C++ [temp.expl.spec]p9:
6376 // A template explicit specialization is in the scope of the
6377 // namespace in which the template was defined.
6379 // We actually implement this paragraph where we set the semantic
6380 // context (in the creation of the ClassTemplateSpecializationDecl),
6381 // but we also maintain the lexical context where the actual
6382 // definition occurs.
6383 Specialization->setLexicalDeclContext(CurContext);
6385 // We may be starting the definition of this specialization.
6386 if (TUK == TUK_Definition)
6387 Specialization->startDefinition();
6389 if (TUK == TUK_Friend) {
6390 FriendDecl *Friend = FriendDecl::Create(Context, CurContext,
6394 Friend->setAccess(AS_public);
6395 CurContext->addDecl(Friend);
6397 // Add the specialization into its lexical context, so that it can
6398 // be seen when iterating through the list of declarations in that
6399 // context. However, specializations are not found by name lookup.
6400 CurContext->addDecl(Specialization);
6402 return Specialization;
6405 Decl *Sema::ActOnTemplateDeclarator(Scope *S,
6406 MultiTemplateParamsArg TemplateParameterLists,
6408 Decl *NewDecl = HandleDeclarator(S, D, TemplateParameterLists);
6409 ActOnDocumentableDecl(NewDecl);
6413 Decl *Sema::ActOnStartOfFunctionTemplateDef(Scope *FnBodyScope,
6414 MultiTemplateParamsArg TemplateParameterLists,
6416 assert(getCurFunctionDecl() == nullptr && "Function parsing confused");
6417 DeclaratorChunk::FunctionTypeInfo &FTI = D.getFunctionTypeInfo();
6419 if (FTI.hasPrototype) {
6420 // FIXME: Diagnose arguments without names in C.
6423 Scope *ParentScope = FnBodyScope->getParent();
6425 D.setFunctionDefinitionKind(FDK_Definition);
6426 Decl *DP = HandleDeclarator(ParentScope, D,
6427 TemplateParameterLists);
6428 return ActOnStartOfFunctionDef(FnBodyScope, DP);
6431 /// \brief Strips various properties off an implicit instantiation
6432 /// that has just been explicitly specialized.
6433 static void StripImplicitInstantiation(NamedDecl *D) {
6436 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
6437 FD->setInlineSpecified(false);
6439 for (auto I : FD->params())
6444 /// \brief Compute the diagnostic location for an explicit instantiation
6445 // declaration or definition.
6446 static SourceLocation DiagLocForExplicitInstantiation(
6447 NamedDecl* D, SourceLocation PointOfInstantiation) {
6448 // Explicit instantiations following a specialization have no effect and
6449 // hence no PointOfInstantiation. In that case, walk decl backwards
6450 // until a valid name loc is found.
6451 SourceLocation PrevDiagLoc = PointOfInstantiation;
6452 for (Decl *Prev = D; Prev && !PrevDiagLoc.isValid();
6453 Prev = Prev->getPreviousDecl()) {
6454 PrevDiagLoc = Prev->getLocation();
6456 assert(PrevDiagLoc.isValid() &&
6457 "Explicit instantiation without point of instantiation?");
6461 /// \brief Diagnose cases where we have an explicit template specialization
6462 /// before/after an explicit template instantiation, producing diagnostics
6463 /// for those cases where they are required and determining whether the
6464 /// new specialization/instantiation will have any effect.
6466 /// \param NewLoc the location of the new explicit specialization or
6469 /// \param NewTSK the kind of the new explicit specialization or instantiation.
6471 /// \param PrevDecl the previous declaration of the entity.
6473 /// \param PrevTSK the kind of the old explicit specialization or instantiatin.
6475 /// \param PrevPointOfInstantiation if valid, indicates where the previus
6476 /// declaration was instantiated (either implicitly or explicitly).
6478 /// \param HasNoEffect will be set to true to indicate that the new
6479 /// specialization or instantiation has no effect and should be ignored.
6481 /// \returns true if there was an error that should prevent the introduction of
6482 /// the new declaration into the AST, false otherwise.
6484 Sema::CheckSpecializationInstantiationRedecl(SourceLocation NewLoc,
6485 TemplateSpecializationKind NewTSK,
6486 NamedDecl *PrevDecl,
6487 TemplateSpecializationKind PrevTSK,
6488 SourceLocation PrevPointOfInstantiation,
6489 bool &HasNoEffect) {
6490 HasNoEffect = false;
6493 case TSK_Undeclared:
6494 case TSK_ImplicitInstantiation:
6496 (PrevTSK == TSK_Undeclared || PrevTSK == TSK_ImplicitInstantiation) &&
6497 "previous declaration must be implicit!");
6500 case TSK_ExplicitSpecialization:
6502 case TSK_Undeclared:
6503 case TSK_ExplicitSpecialization:
6504 // Okay, we're just specializing something that is either already
6505 // explicitly specialized or has merely been mentioned without any
6509 case TSK_ImplicitInstantiation:
6510 if (PrevPointOfInstantiation.isInvalid()) {
6511 // The declaration itself has not actually been instantiated, so it is
6512 // still okay to specialize it.
6513 StripImplicitInstantiation(PrevDecl);
6518 case TSK_ExplicitInstantiationDeclaration:
6519 case TSK_ExplicitInstantiationDefinition:
6520 assert((PrevTSK == TSK_ImplicitInstantiation ||
6521 PrevPointOfInstantiation.isValid()) &&
6522 "Explicit instantiation without point of instantiation?");
6524 // C++ [temp.expl.spec]p6:
6525 // If a template, a member template or the member of a class template
6526 // is explicitly specialized then that specialization shall be declared
6527 // before the first use of that specialization that would cause an
6528 // implicit instantiation to take place, in every translation unit in
6529 // which such a use occurs; no diagnostic is required.
6530 for (Decl *Prev = PrevDecl; Prev; Prev = Prev->getPreviousDecl()) {
6531 // Is there any previous explicit specialization declaration?
6532 if (getTemplateSpecializationKind(Prev) == TSK_ExplicitSpecialization)
6536 Diag(NewLoc, diag::err_specialization_after_instantiation)
6538 Diag(PrevPointOfInstantiation, diag::note_instantiation_required_here)
6539 << (PrevTSK != TSK_ImplicitInstantiation);
6544 case TSK_ExplicitInstantiationDeclaration:
6546 case TSK_ExplicitInstantiationDeclaration:
6547 // This explicit instantiation declaration is redundant (that's okay).
6551 case TSK_Undeclared:
6552 case TSK_ImplicitInstantiation:
6553 // We're explicitly instantiating something that may have already been
6554 // implicitly instantiated; that's fine.
6557 case TSK_ExplicitSpecialization:
6558 // C++0x [temp.explicit]p4:
6559 // For a given set of template parameters, if an explicit instantiation
6560 // of a template appears after a declaration of an explicit
6561 // specialization for that template, the explicit instantiation has no
6566 case TSK_ExplicitInstantiationDefinition:
6567 // C++0x [temp.explicit]p10:
6568 // If an entity is the subject of both an explicit instantiation
6569 // declaration and an explicit instantiation definition in the same
6570 // translation unit, the definition shall follow the declaration.
6572 diag::err_explicit_instantiation_declaration_after_definition);
6574 // Explicit instantiations following a specialization have no effect and
6575 // hence no PrevPointOfInstantiation. In that case, walk decl backwards
6576 // until a valid name loc is found.
6577 Diag(DiagLocForExplicitInstantiation(PrevDecl, PrevPointOfInstantiation),
6578 diag::note_explicit_instantiation_definition_here);
6583 case TSK_ExplicitInstantiationDefinition:
6585 case TSK_Undeclared:
6586 case TSK_ImplicitInstantiation:
6587 // We're explicitly instantiating something that may have already been
6588 // implicitly instantiated; that's fine.
6591 case TSK_ExplicitSpecialization:
6592 // C++ DR 259, C++0x [temp.explicit]p4:
6593 // For a given set of template parameters, if an explicit
6594 // instantiation of a template appears after a declaration of
6595 // an explicit specialization for that template, the explicit
6596 // instantiation has no effect.
6598 // In C++98/03 mode, we only give an extension warning here, because it
6599 // is not harmful to try to explicitly instantiate something that
6600 // has been explicitly specialized.
6601 Diag(NewLoc, getLangOpts().CPlusPlus11 ?
6602 diag::warn_cxx98_compat_explicit_instantiation_after_specialization :
6603 diag::ext_explicit_instantiation_after_specialization)
6605 Diag(PrevDecl->getLocation(),
6606 diag::note_previous_template_specialization);
6610 case TSK_ExplicitInstantiationDeclaration:
6611 // We're explicity instantiating a definition for something for which we
6612 // were previously asked to suppress instantiations. That's fine.
6614 // C++0x [temp.explicit]p4:
6615 // For a given set of template parameters, if an explicit instantiation
6616 // of a template appears after a declaration of an explicit
6617 // specialization for that template, the explicit instantiation has no
6619 for (Decl *Prev = PrevDecl; Prev; Prev = Prev->getPreviousDecl()) {
6620 // Is there any previous explicit specialization declaration?
6621 if (getTemplateSpecializationKind(Prev) == TSK_ExplicitSpecialization) {
6629 case TSK_ExplicitInstantiationDefinition:
6630 // C++0x [temp.spec]p5:
6631 // For a given template and a given set of template-arguments,
6632 // - an explicit instantiation definition shall appear at most once
6635 // MSVCCompat: MSVC silently ignores duplicate explicit instantiations.
6636 Diag(NewLoc, (getLangOpts().MSVCCompat)
6637 ? diag::ext_explicit_instantiation_duplicate
6638 : diag::err_explicit_instantiation_duplicate)
6640 Diag(DiagLocForExplicitInstantiation(PrevDecl, PrevPointOfInstantiation),
6641 diag::note_previous_explicit_instantiation);
6647 llvm_unreachable("Missing specialization/instantiation case?");
6650 /// \brief Perform semantic analysis for the given dependent function
6651 /// template specialization.
6653 /// The only possible way to get a dependent function template specialization
6654 /// is with a friend declaration, like so:
6657 /// template \<class T> void foo(T);
6658 /// template \<class T> class A {
6659 /// friend void foo<>(T);
6663 /// There really isn't any useful analysis we can do here, so we
6664 /// just store the information.
6666 Sema::CheckDependentFunctionTemplateSpecialization(FunctionDecl *FD,
6667 const TemplateArgumentListInfo &ExplicitTemplateArgs,
6668 LookupResult &Previous) {
6669 // Remove anything from Previous that isn't a function template in
6670 // the correct context.
6671 DeclContext *FDLookupContext = FD->getDeclContext()->getRedeclContext();
6672 LookupResult::Filter F = Previous.makeFilter();
6673 while (F.hasNext()) {
6674 NamedDecl *D = F.next()->getUnderlyingDecl();
6675 if (!isa<FunctionTemplateDecl>(D) ||
6676 !FDLookupContext->InEnclosingNamespaceSetOf(
6677 D->getDeclContext()->getRedeclContext()))
6682 // Should this be diagnosed here?
6683 if (Previous.empty()) return true;
6685 FD->setDependentTemplateSpecialization(Context, Previous.asUnresolvedSet(),
6686 ExplicitTemplateArgs);
6690 /// \brief Perform semantic analysis for the given function template
6693 /// This routine performs all of the semantic analysis required for an
6694 /// explicit function template specialization. On successful completion,
6695 /// the function declaration \p FD will become a function template
6698 /// \param FD the function declaration, which will be updated to become a
6699 /// function template specialization.
6701 /// \param ExplicitTemplateArgs the explicitly-provided template arguments,
6702 /// if any. Note that this may be valid info even when 0 arguments are
6703 /// explicitly provided as in, e.g., \c void sort<>(char*, char*);
6704 /// as it anyway contains info on the angle brackets locations.
6706 /// \param Previous the set of declarations that may be specialized by
6707 /// this function specialization.
6708 bool Sema::CheckFunctionTemplateSpecialization(
6709 FunctionDecl *FD, TemplateArgumentListInfo *ExplicitTemplateArgs,
6710 LookupResult &Previous) {
6711 // The set of function template specializations that could match this
6712 // explicit function template specialization.
6713 UnresolvedSet<8> Candidates;
6714 TemplateSpecCandidateSet FailedCandidates(FD->getLocation());
6716 DeclContext *FDLookupContext = FD->getDeclContext()->getRedeclContext();
6717 for (LookupResult::iterator I = Previous.begin(), E = Previous.end();
6719 NamedDecl *Ovl = (*I)->getUnderlyingDecl();
6720 if (FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(Ovl)) {
6721 // Only consider templates found within the same semantic lookup scope as
6723 if (!FDLookupContext->InEnclosingNamespaceSetOf(
6724 Ovl->getDeclContext()->getRedeclContext()))
6727 // When matching a constexpr member function template specialization
6728 // against the primary template, we don't yet know whether the
6729 // specialization has an implicit 'const' (because we don't know whether
6730 // it will be a static member function until we know which template it
6731 // specializes), so adjust it now assuming it specializes this template.
6732 QualType FT = FD->getType();
6733 if (FD->isConstexpr()) {
6734 CXXMethodDecl *OldMD =
6735 dyn_cast<CXXMethodDecl>(FunTmpl->getTemplatedDecl());
6736 if (OldMD && OldMD->isConst()) {
6737 const FunctionProtoType *FPT = FT->castAs<FunctionProtoType>();
6738 FunctionProtoType::ExtProtoInfo EPI = FPT->getExtProtoInfo();
6739 EPI.TypeQuals |= Qualifiers::Const;
6740 FT = Context.getFunctionType(FPT->getReturnType(),
6741 FPT->getParamTypes(), EPI);
6745 // C++ [temp.expl.spec]p11:
6746 // A trailing template-argument can be left unspecified in the
6747 // template-id naming an explicit function template specialization
6748 // provided it can be deduced from the function argument type.
6749 // Perform template argument deduction to determine whether we may be
6750 // specializing this template.
6751 // FIXME: It is somewhat wasteful to build
6752 TemplateDeductionInfo Info(FailedCandidates.getLocation());
6753 FunctionDecl *Specialization = nullptr;
6754 if (TemplateDeductionResult TDK = DeduceTemplateArguments(
6755 cast<FunctionTemplateDecl>(FunTmpl->getFirstDecl()),
6756 ExplicitTemplateArgs, FT, Specialization, Info)) {
6757 // Template argument deduction failed; record why it failed, so
6758 // that we can provide nifty diagnostics.
6759 FailedCandidates.addCandidate()
6760 .set(FunTmpl->getTemplatedDecl(),
6761 MakeDeductionFailureInfo(Context, TDK, Info));
6766 // Record this candidate.
6767 Candidates.addDecl(Specialization, I.getAccess());
6771 // Find the most specialized function template.
6772 UnresolvedSetIterator Result = getMostSpecialized(
6773 Candidates.begin(), Candidates.end(), FailedCandidates,
6775 PDiag(diag::err_function_template_spec_no_match) << FD->getDeclName(),
6776 PDiag(diag::err_function_template_spec_ambiguous)
6777 << FD->getDeclName() << (ExplicitTemplateArgs != nullptr),
6778 PDiag(diag::note_function_template_spec_matched));
6780 if (Result == Candidates.end())
6783 // Ignore access information; it doesn't figure into redeclaration checking.
6784 FunctionDecl *Specialization = cast<FunctionDecl>(*Result);
6786 FunctionTemplateSpecializationInfo *SpecInfo
6787 = Specialization->getTemplateSpecializationInfo();
6788 assert(SpecInfo && "Function template specialization info missing?");
6790 // Note: do not overwrite location info if previous template
6791 // specialization kind was explicit.
6792 TemplateSpecializationKind TSK = SpecInfo->getTemplateSpecializationKind();
6793 if (TSK == TSK_Undeclared || TSK == TSK_ImplicitInstantiation) {
6794 Specialization->setLocation(FD->getLocation());
6795 // C++11 [dcl.constexpr]p1: An explicit specialization of a constexpr
6796 // function can differ from the template declaration with respect to
6797 // the constexpr specifier.
6798 Specialization->setConstexpr(FD->isConstexpr());
6801 // FIXME: Check if the prior specialization has a point of instantiation.
6802 // If so, we have run afoul of .
6804 // If this is a friend declaration, then we're not really declaring
6805 // an explicit specialization.
6806 bool isFriend = (FD->getFriendObjectKind() != Decl::FOK_None);
6808 // Check the scope of this explicit specialization.
6810 CheckTemplateSpecializationScope(*this,
6811 Specialization->getPrimaryTemplate(),
6812 Specialization, FD->getLocation(),
6816 // C++ [temp.expl.spec]p6:
6817 // If a template, a member template or the member of a class template is
6818 // explicitly specialized then that specialization shall be declared
6819 // before the first use of that specialization that would cause an implicit
6820 // instantiation to take place, in every translation unit in which such a
6821 // use occurs; no diagnostic is required.
6822 bool HasNoEffect = false;
6824 CheckSpecializationInstantiationRedecl(FD->getLocation(),
6825 TSK_ExplicitSpecialization,
6827 SpecInfo->getTemplateSpecializationKind(),
6828 SpecInfo->getPointOfInstantiation(),
6832 // Mark the prior declaration as an explicit specialization, so that later
6833 // clients know that this is an explicit specialization.
6835 SpecInfo->setTemplateSpecializationKind(TSK_ExplicitSpecialization);
6836 MarkUnusedFileScopedDecl(Specialization);
6839 // Turn the given function declaration into a function template
6840 // specialization, with the template arguments from the previous
6842 // Take copies of (semantic and syntactic) template argument lists.
6843 const TemplateArgumentList* TemplArgs = new (Context)
6844 TemplateArgumentList(Specialization->getTemplateSpecializationArgs());
6845 FD->setFunctionTemplateSpecialization(Specialization->getPrimaryTemplate(),
6846 TemplArgs, /*InsertPos=*/nullptr,
6847 SpecInfo->getTemplateSpecializationKind(),
6848 ExplicitTemplateArgs);
6850 // The "previous declaration" for this function template specialization is
6851 // the prior function template specialization.
6853 Previous.addDecl(Specialization);
6857 /// \brief Perform semantic analysis for the given non-template member
6860 /// This routine performs all of the semantic analysis required for an
6861 /// explicit member function specialization. On successful completion,
6862 /// the function declaration \p FD will become a member function
6865 /// \param Member the member declaration, which will be updated to become a
6868 /// \param Previous the set of declarations, one of which may be specialized
6869 /// by this function specialization; the set will be modified to contain the
6870 /// redeclared member.
6872 Sema::CheckMemberSpecialization(NamedDecl *Member, LookupResult &Previous) {
6873 assert(!isa<TemplateDecl>(Member) && "Only for non-template members");
6875 // Try to find the member we are instantiating.
6876 NamedDecl *Instantiation = nullptr;
6877 NamedDecl *InstantiatedFrom = nullptr;
6878 MemberSpecializationInfo *MSInfo = nullptr;
6880 if (Previous.empty()) {
6881 // Nowhere to look anyway.
6882 } else if (FunctionDecl *Function = dyn_cast<FunctionDecl>(Member)) {
6883 for (LookupResult::iterator I = Previous.begin(), E = Previous.end();
6885 NamedDecl *D = (*I)->getUnderlyingDecl();
6886 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(D)) {
6887 QualType Adjusted = Function->getType();
6888 if (!hasExplicitCallingConv(Adjusted))
6889 Adjusted = adjustCCAndNoReturn(Adjusted, Method->getType());
6890 if (Context.hasSameType(Adjusted, Method->getType())) {
6891 Instantiation = Method;
6892 InstantiatedFrom = Method->getInstantiatedFromMemberFunction();
6893 MSInfo = Method->getMemberSpecializationInfo();
6898 } else if (isa<VarDecl>(Member)) {
6900 if (Previous.isSingleResult() &&
6901 (PrevVar = dyn_cast<VarDecl>(Previous.getFoundDecl())))
6902 if (PrevVar->isStaticDataMember()) {
6903 Instantiation = PrevVar;
6904 InstantiatedFrom = PrevVar->getInstantiatedFromStaticDataMember();
6905 MSInfo = PrevVar->getMemberSpecializationInfo();
6907 } else if (isa<RecordDecl>(Member)) {
6908 CXXRecordDecl *PrevRecord;
6909 if (Previous.isSingleResult() &&
6910 (PrevRecord = dyn_cast<CXXRecordDecl>(Previous.getFoundDecl()))) {
6911 Instantiation = PrevRecord;
6912 InstantiatedFrom = PrevRecord->getInstantiatedFromMemberClass();
6913 MSInfo = PrevRecord->getMemberSpecializationInfo();
6915 } else if (isa<EnumDecl>(Member)) {
6917 if (Previous.isSingleResult() &&
6918 (PrevEnum = dyn_cast<EnumDecl>(Previous.getFoundDecl()))) {
6919 Instantiation = PrevEnum;
6920 InstantiatedFrom = PrevEnum->getInstantiatedFromMemberEnum();
6921 MSInfo = PrevEnum->getMemberSpecializationInfo();
6925 if (!Instantiation) {
6926 // There is no previous declaration that matches. Since member
6927 // specializations are always out-of-line, the caller will complain about
6928 // this mismatch later.
6932 // If this is a friend, just bail out here before we start turning
6933 // things into explicit specializations.
6934 if (Member->getFriendObjectKind() != Decl::FOK_None) {
6935 // Preserve instantiation information.
6936 if (InstantiatedFrom && isa<CXXMethodDecl>(Member)) {
6937 cast<CXXMethodDecl>(Member)->setInstantiationOfMemberFunction(
6938 cast<CXXMethodDecl>(InstantiatedFrom),
6939 cast<CXXMethodDecl>(Instantiation)->getTemplateSpecializationKind());
6940 } else if (InstantiatedFrom && isa<CXXRecordDecl>(Member)) {
6941 cast<CXXRecordDecl>(Member)->setInstantiationOfMemberClass(
6942 cast<CXXRecordDecl>(InstantiatedFrom),
6943 cast<CXXRecordDecl>(Instantiation)->getTemplateSpecializationKind());
6947 Previous.addDecl(Instantiation);
6951 // Make sure that this is a specialization of a member.
6952 if (!InstantiatedFrom) {
6953 Diag(Member->getLocation(), diag::err_spec_member_not_instantiated)
6955 Diag(Instantiation->getLocation(), diag::note_specialized_decl);
6959 // C++ [temp.expl.spec]p6:
6960 // If a template, a member template or the member of a class template is
6961 // explicitly specialized then that specialization shall be declared
6962 // before the first use of that specialization that would cause an implicit
6963 // instantiation to take place, in every translation unit in which such a
6964 // use occurs; no diagnostic is required.
6965 assert(MSInfo && "Member specialization info missing?");
6967 bool HasNoEffect = false;
6968 if (CheckSpecializationInstantiationRedecl(Member->getLocation(),
6969 TSK_ExplicitSpecialization,
6971 MSInfo->getTemplateSpecializationKind(),
6972 MSInfo->getPointOfInstantiation(),
6976 // Check the scope of this explicit specialization.
6977 if (CheckTemplateSpecializationScope(*this,
6979 Instantiation, Member->getLocation(),
6983 // Note that this is an explicit instantiation of a member.
6984 // the original declaration to note that it is an explicit specialization
6985 // (if it was previously an implicit instantiation). This latter step
6986 // makes bookkeeping easier.
6987 if (isa<FunctionDecl>(Member)) {
6988 FunctionDecl *InstantiationFunction = cast<FunctionDecl>(Instantiation);
6989 if (InstantiationFunction->getTemplateSpecializationKind() ==
6990 TSK_ImplicitInstantiation) {
6991 InstantiationFunction->setTemplateSpecializationKind(
6992 TSK_ExplicitSpecialization);
6993 InstantiationFunction->setLocation(Member->getLocation());
6996 cast<FunctionDecl>(Member)->setInstantiationOfMemberFunction(
6997 cast<CXXMethodDecl>(InstantiatedFrom),
6998 TSK_ExplicitSpecialization);
6999 MarkUnusedFileScopedDecl(InstantiationFunction);
7000 } else if (isa<VarDecl>(Member)) {
7001 VarDecl *InstantiationVar = cast<VarDecl>(Instantiation);
7002 if (InstantiationVar->getTemplateSpecializationKind() ==
7003 TSK_ImplicitInstantiation) {
7004 InstantiationVar->setTemplateSpecializationKind(
7005 TSK_ExplicitSpecialization);
7006 InstantiationVar->setLocation(Member->getLocation());
7009 cast<VarDecl>(Member)->setInstantiationOfStaticDataMember(
7010 cast<VarDecl>(InstantiatedFrom), TSK_ExplicitSpecialization);
7011 MarkUnusedFileScopedDecl(InstantiationVar);
7012 } else if (isa<CXXRecordDecl>(Member)) {
7013 CXXRecordDecl *InstantiationClass = cast<CXXRecordDecl>(Instantiation);
7014 if (InstantiationClass->getTemplateSpecializationKind() ==
7015 TSK_ImplicitInstantiation) {
7016 InstantiationClass->setTemplateSpecializationKind(
7017 TSK_ExplicitSpecialization);
7018 InstantiationClass->setLocation(Member->getLocation());
7021 cast<CXXRecordDecl>(Member)->setInstantiationOfMemberClass(
7022 cast<CXXRecordDecl>(InstantiatedFrom),
7023 TSK_ExplicitSpecialization);
7025 assert(isa<EnumDecl>(Member) && "Only member enums remain");
7026 EnumDecl *InstantiationEnum = cast<EnumDecl>(Instantiation);
7027 if (InstantiationEnum->getTemplateSpecializationKind() ==
7028 TSK_ImplicitInstantiation) {
7029 InstantiationEnum->setTemplateSpecializationKind(
7030 TSK_ExplicitSpecialization);
7031 InstantiationEnum->setLocation(Member->getLocation());
7034 cast<EnumDecl>(Member)->setInstantiationOfMemberEnum(
7035 cast<EnumDecl>(InstantiatedFrom), TSK_ExplicitSpecialization);
7038 // Save the caller the trouble of having to figure out which declaration
7039 // this specialization matches.
7041 Previous.addDecl(Instantiation);
7045 /// \brief Check the scope of an explicit instantiation.
7047 /// \returns true if a serious error occurs, false otherwise.
7048 static bool CheckExplicitInstantiationScope(Sema &S, NamedDecl *D,
7049 SourceLocation InstLoc,
7050 bool WasQualifiedName) {
7051 DeclContext *OrigContext= D->getDeclContext()->getEnclosingNamespaceContext();
7052 DeclContext *CurContext = S.CurContext->getRedeclContext();
7054 if (CurContext->isRecord()) {
7055 S.Diag(InstLoc, diag::err_explicit_instantiation_in_class)
7060 // C++11 [temp.explicit]p3:
7061 // An explicit instantiation shall appear in an enclosing namespace of its
7062 // template. If the name declared in the explicit instantiation is an
7063 // unqualified name, the explicit instantiation shall appear in the
7064 // namespace where its template is declared or, if that namespace is inline
7065 // (7.3.1), any namespace from its enclosing namespace set.
7067 // This is DR275, which we do not retroactively apply to C++98/03.
7068 if (WasQualifiedName) {
7069 if (CurContext->Encloses(OrigContext))
7072 if (CurContext->InEnclosingNamespaceSetOf(OrigContext))
7076 if (NamespaceDecl *NS = dyn_cast<NamespaceDecl>(OrigContext)) {
7077 if (WasQualifiedName)
7079 S.getLangOpts().CPlusPlus11?
7080 diag::err_explicit_instantiation_out_of_scope :
7081 diag::warn_explicit_instantiation_out_of_scope_0x)
7085 S.getLangOpts().CPlusPlus11?
7086 diag::err_explicit_instantiation_unqualified_wrong_namespace :
7087 diag::warn_explicit_instantiation_unqualified_wrong_namespace_0x)
7091 S.getLangOpts().CPlusPlus11?
7092 diag::err_explicit_instantiation_must_be_global :
7093 diag::warn_explicit_instantiation_must_be_global_0x)
7095 S.Diag(D->getLocation(), diag::note_explicit_instantiation_here);
7099 /// \brief Determine whether the given scope specifier has a template-id in it.
7100 static bool ScopeSpecifierHasTemplateId(const CXXScopeSpec &SS) {
7104 // C++11 [temp.explicit]p3:
7105 // If the explicit instantiation is for a member function, a member class
7106 // or a static data member of a class template specialization, the name of
7107 // the class template specialization in the qualified-id for the member
7108 // name shall be a simple-template-id.
7110 // C++98 has the same restriction, just worded differently.
7111 for (NestedNameSpecifier *NNS = SS.getScopeRep(); NNS;
7112 NNS = NNS->getPrefix())
7113 if (const Type *T = NNS->getAsType())
7114 if (isa<TemplateSpecializationType>(T))
7120 // Explicit instantiation of a class template specialization
7122 Sema::ActOnExplicitInstantiation(Scope *S,
7123 SourceLocation ExternLoc,
7124 SourceLocation TemplateLoc,
7126 SourceLocation KWLoc,
7127 const CXXScopeSpec &SS,
7128 TemplateTy TemplateD,
7129 SourceLocation TemplateNameLoc,
7130 SourceLocation LAngleLoc,
7131 ASTTemplateArgsPtr TemplateArgsIn,
7132 SourceLocation RAngleLoc,
7133 AttributeList *Attr) {
7134 // Find the class template we're specializing
7135 TemplateName Name = TemplateD.get();
7136 TemplateDecl *TD = Name.getAsTemplateDecl();
7137 // Check that the specialization uses the same tag kind as the
7138 // original template.
7139 TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec);
7140 assert(Kind != TTK_Enum &&
7141 "Invalid enum tag in class template explicit instantiation!");
7143 if (isa<TypeAliasTemplateDecl>(TD)) {
7144 Diag(KWLoc, diag::err_tag_reference_non_tag) << Kind;
7145 Diag(TD->getTemplatedDecl()->getLocation(),
7146 diag::note_previous_use);
7150 ClassTemplateDecl *ClassTemplate = cast<ClassTemplateDecl>(TD);
7152 if (!isAcceptableTagRedeclaration(ClassTemplate->getTemplatedDecl(),
7153 Kind, /*isDefinition*/false, KWLoc,
7154 *ClassTemplate->getIdentifier())) {
7155 Diag(KWLoc, diag::err_use_with_wrong_tag)
7157 << FixItHint::CreateReplacement(KWLoc,
7158 ClassTemplate->getTemplatedDecl()->getKindName());
7159 Diag(ClassTemplate->getTemplatedDecl()->getLocation(),
7160 diag::note_previous_use);
7161 Kind = ClassTemplate->getTemplatedDecl()->getTagKind();
7164 // C++0x [temp.explicit]p2:
7165 // There are two forms of explicit instantiation: an explicit instantiation
7166 // definition and an explicit instantiation declaration. An explicit
7167 // instantiation declaration begins with the extern keyword. [...]
7168 TemplateSpecializationKind TSK
7169 = ExternLoc.isInvalid()? TSK_ExplicitInstantiationDefinition
7170 : TSK_ExplicitInstantiationDeclaration;
7172 // Translate the parser's template argument list in our AST format.
7173 TemplateArgumentListInfo TemplateArgs(LAngleLoc, RAngleLoc);
7174 translateTemplateArguments(TemplateArgsIn, TemplateArgs);
7176 // Check that the template argument list is well-formed for this
7178 SmallVector<TemplateArgument, 4> Converted;
7179 if (CheckTemplateArgumentList(ClassTemplate, TemplateNameLoc,
7180 TemplateArgs, false, Converted))
7183 // Find the class template specialization declaration that
7184 // corresponds to these arguments.
7185 void *InsertPos = nullptr;
7186 ClassTemplateSpecializationDecl *PrevDecl
7187 = ClassTemplate->findSpecialization(Converted, InsertPos);
7189 TemplateSpecializationKind PrevDecl_TSK
7190 = PrevDecl ? PrevDecl->getTemplateSpecializationKind() : TSK_Undeclared;
7192 // C++0x [temp.explicit]p2:
7193 // [...] An explicit instantiation shall appear in an enclosing
7194 // namespace of its template. [...]
7196 // This is C++ DR 275.
7197 if (CheckExplicitInstantiationScope(*this, ClassTemplate, TemplateNameLoc,
7201 ClassTemplateSpecializationDecl *Specialization = nullptr;
7203 bool HasNoEffect = false;
7205 if (CheckSpecializationInstantiationRedecl(TemplateNameLoc, TSK,
7206 PrevDecl, PrevDecl_TSK,
7207 PrevDecl->getPointOfInstantiation(),
7211 // Even though HasNoEffect == true means that this explicit instantiation
7212 // has no effect on semantics, we go on to put its syntax in the AST.
7214 if (PrevDecl_TSK == TSK_ImplicitInstantiation ||
7215 PrevDecl_TSK == TSK_Undeclared) {
7216 // Since the only prior class template specialization with these
7217 // arguments was referenced but not declared, reuse that
7218 // declaration node as our own, updating the source location
7219 // for the template name to reflect our new declaration.
7220 // (Other source locations will be updated later.)
7221 Specialization = PrevDecl;
7222 Specialization->setLocation(TemplateNameLoc);
7227 if (!Specialization) {
7228 // Create a new class template specialization declaration node for
7229 // this explicit specialization.
7231 = ClassTemplateSpecializationDecl::Create(Context, Kind,
7232 ClassTemplate->getDeclContext(),
7233 KWLoc, TemplateNameLoc,
7238 SetNestedNameSpecifier(Specialization, SS);
7240 if (!HasNoEffect && !PrevDecl) {
7241 // Insert the new specialization.
7242 ClassTemplate->AddSpecialization(Specialization, InsertPos);
7246 // Build the fully-sugared type for this explicit instantiation as
7247 // the user wrote in the explicit instantiation itself. This means
7248 // that we'll pretty-print the type retrieved from the
7249 // specialization's declaration the way that the user actually wrote
7250 // the explicit instantiation, rather than formatting the name based
7251 // on the "canonical" representation used to store the template
7252 // arguments in the specialization.
7253 TypeSourceInfo *WrittenTy
7254 = Context.getTemplateSpecializationTypeInfo(Name, TemplateNameLoc,
7256 Context.getTypeDeclType(Specialization));
7257 Specialization->setTypeAsWritten(WrittenTy);
7259 // Set source locations for keywords.
7260 Specialization->setExternLoc(ExternLoc);
7261 Specialization->setTemplateKeywordLoc(TemplateLoc);
7262 Specialization->setRBraceLoc(SourceLocation());
7265 ProcessDeclAttributeList(S, Specialization, Attr);
7267 // Add the explicit instantiation into its lexical context. However,
7268 // since explicit instantiations are never found by name lookup, we
7269 // just put it into the declaration context directly.
7270 Specialization->setLexicalDeclContext(CurContext);
7271 CurContext->addDecl(Specialization);
7273 // Syntax is now OK, so return if it has no other effect on semantics.
7275 // Set the template specialization kind.
7276 Specialization->setTemplateSpecializationKind(TSK);
7277 return Specialization;
7280 // C++ [temp.explicit]p3:
7281 // A definition of a class template or class member template
7282 // shall be in scope at the point of the explicit instantiation of
7283 // the class template or class member template.
7285 // This check comes when we actually try to perform the
7287 ClassTemplateSpecializationDecl *Def
7288 = cast_or_null<ClassTemplateSpecializationDecl>(
7289 Specialization->getDefinition());
7291 InstantiateClassTemplateSpecialization(TemplateNameLoc, Specialization, TSK);
7292 else if (TSK == TSK_ExplicitInstantiationDefinition) {
7293 MarkVTableUsed(TemplateNameLoc, Specialization, true);
7294 Specialization->setPointOfInstantiation(Def->getPointOfInstantiation());
7297 // Instantiate the members of this class template specialization.
7298 Def = cast_or_null<ClassTemplateSpecializationDecl>(
7299 Specialization->getDefinition());
7301 TemplateSpecializationKind Old_TSK = Def->getTemplateSpecializationKind();
7303 // Fix a TSK_ExplicitInstantiationDeclaration followed by a
7304 // TSK_ExplicitInstantiationDefinition
7305 if (Old_TSK == TSK_ExplicitInstantiationDeclaration &&
7306 TSK == TSK_ExplicitInstantiationDefinition)
7307 // FIXME: Need to notify the ASTMutationListener that we did this.
7308 Def->setTemplateSpecializationKind(TSK);
7310 InstantiateClassTemplateSpecializationMembers(TemplateNameLoc, Def, TSK);
7313 // Set the template specialization kind.
7314 Specialization->setTemplateSpecializationKind(TSK);
7315 return Specialization;
7318 // Explicit instantiation of a member class of a class template.
7320 Sema::ActOnExplicitInstantiation(Scope *S,
7321 SourceLocation ExternLoc,
7322 SourceLocation TemplateLoc,
7324 SourceLocation KWLoc,
7326 IdentifierInfo *Name,
7327 SourceLocation NameLoc,
7328 AttributeList *Attr) {
7331 bool IsDependent = false;
7332 Decl *TagD = ActOnTag(S, TagSpec, Sema::TUK_Reference,
7333 KWLoc, SS, Name, NameLoc, Attr, AS_none,
7334 /*ModulePrivateLoc=*/SourceLocation(),
7335 MultiTemplateParamsArg(), Owned, IsDependent,
7336 SourceLocation(), false, TypeResult(),
7337 /*IsTypeSpecifier*/false);
7338 assert(!IsDependent && "explicit instantiation of dependent name not yet handled");
7343 TagDecl *Tag = cast<TagDecl>(TagD);
7344 assert(!Tag->isEnum() && "shouldn't see enumerations here");
7346 if (Tag->isInvalidDecl())
7349 CXXRecordDecl *Record = cast<CXXRecordDecl>(Tag);
7350 CXXRecordDecl *Pattern = Record->getInstantiatedFromMemberClass();
7352 Diag(TemplateLoc, diag::err_explicit_instantiation_nontemplate_type)
7353 << Context.getTypeDeclType(Record);
7354 Diag(Record->getLocation(), diag::note_nontemplate_decl_here);
7358 // C++0x [temp.explicit]p2:
7359 // If the explicit instantiation is for a class or member class, the
7360 // elaborated-type-specifier in the declaration shall include a
7361 // simple-template-id.
7363 // C++98 has the same restriction, just worded differently.
7364 if (!ScopeSpecifierHasTemplateId(SS))
7365 Diag(TemplateLoc, diag::ext_explicit_instantiation_without_qualified_id)
7366 << Record << SS.getRange();
7368 // C++0x [temp.explicit]p2:
7369 // There are two forms of explicit instantiation: an explicit instantiation
7370 // definition and an explicit instantiation declaration. An explicit
7371 // instantiation declaration begins with the extern keyword. [...]
7372 TemplateSpecializationKind TSK
7373 = ExternLoc.isInvalid()? TSK_ExplicitInstantiationDefinition
7374 : TSK_ExplicitInstantiationDeclaration;
7376 // C++0x [temp.explicit]p2:
7377 // [...] An explicit instantiation shall appear in an enclosing
7378 // namespace of its template. [...]
7380 // This is C++ DR 275.
7381 CheckExplicitInstantiationScope(*this, Record, NameLoc, true);
7383 // Verify that it is okay to explicitly instantiate here.
7384 CXXRecordDecl *PrevDecl
7385 = cast_or_null<CXXRecordDecl>(Record->getPreviousDecl());
7386 if (!PrevDecl && Record->getDefinition())
7389 MemberSpecializationInfo *MSInfo = PrevDecl->getMemberSpecializationInfo();
7390 bool HasNoEffect = false;
7391 assert(MSInfo && "No member specialization information?");
7392 if (CheckSpecializationInstantiationRedecl(TemplateLoc, TSK,
7394 MSInfo->getTemplateSpecializationKind(),
7395 MSInfo->getPointOfInstantiation(),
7402 CXXRecordDecl *RecordDef
7403 = cast_or_null<CXXRecordDecl>(Record->getDefinition());
7405 // C++ [temp.explicit]p3:
7406 // A definition of a member class of a class template shall be in scope
7407 // at the point of an explicit instantiation of the member class.
7409 = cast_or_null<CXXRecordDecl>(Pattern->getDefinition());
7411 Diag(TemplateLoc, diag::err_explicit_instantiation_undefined_member)
7412 << 0 << Record->getDeclName() << Record->getDeclContext();
7413 Diag(Pattern->getLocation(), diag::note_forward_declaration)
7417 if (InstantiateClass(NameLoc, Record, Def,
7418 getTemplateInstantiationArgs(Record),
7422 RecordDef = cast_or_null<CXXRecordDecl>(Record->getDefinition());
7428 // Instantiate all of the members of the class.
7429 InstantiateClassMembers(NameLoc, RecordDef,
7430 getTemplateInstantiationArgs(Record), TSK);
7432 if (TSK == TSK_ExplicitInstantiationDefinition)
7433 MarkVTableUsed(NameLoc, RecordDef, true);
7435 // FIXME: We don't have any representation for explicit instantiations of
7436 // member classes. Such a representation is not needed for compilation, but it
7437 // should be available for clients that want to see all of the declarations in
7442 DeclResult Sema::ActOnExplicitInstantiation(Scope *S,
7443 SourceLocation ExternLoc,
7444 SourceLocation TemplateLoc,
7446 // Explicit instantiations always require a name.
7447 // TODO: check if/when DNInfo should replace Name.
7448 DeclarationNameInfo NameInfo = GetNameForDeclarator(D);
7449 DeclarationName Name = NameInfo.getName();
7451 if (!D.isInvalidType())
7452 Diag(D.getDeclSpec().getLocStart(),
7453 diag::err_explicit_instantiation_requires_name)
7454 << D.getDeclSpec().getSourceRange()
7455 << D.getSourceRange();
7460 // The scope passed in may not be a decl scope. Zip up the scope tree until
7461 // we find one that is.
7462 while ((S->getFlags() & Scope::DeclScope) == 0 ||
7463 (S->getFlags() & Scope::TemplateParamScope) != 0)
7466 // Determine the type of the declaration.
7467 TypeSourceInfo *T = GetTypeForDeclarator(D, S);
7468 QualType R = T->getType();
7473 // A storage-class-specifier shall not be specified in [...] an explicit
7474 // instantiation (14.7.2) directive.
7475 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) {
7476 Diag(D.getIdentifierLoc(), diag::err_explicit_instantiation_of_typedef)
7479 } else if (D.getDeclSpec().getStorageClassSpec()
7480 != DeclSpec::SCS_unspecified) {
7481 // Complain about then remove the storage class specifier.
7482 Diag(D.getIdentifierLoc(), diag::err_explicit_instantiation_storage_class)
7483 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc());
7485 D.getMutableDeclSpec().ClearStorageClassSpecs();
7488 // C++0x [temp.explicit]p1:
7489 // [...] An explicit instantiation of a function template shall not use the
7490 // inline or constexpr specifiers.
7491 // Presumably, this also applies to member functions of class templates as
7493 if (D.getDeclSpec().isInlineSpecified())
7494 Diag(D.getDeclSpec().getInlineSpecLoc(),
7495 getLangOpts().CPlusPlus11 ?
7496 diag::err_explicit_instantiation_inline :
7497 diag::warn_explicit_instantiation_inline_0x)
7498 << FixItHint::CreateRemoval(D.getDeclSpec().getInlineSpecLoc());
7499 if (D.getDeclSpec().isConstexprSpecified() && R->isFunctionType())
7500 // FIXME: Add a fix-it to remove the 'constexpr' and add a 'const' if one is
7501 // not already specified.
7502 Diag(D.getDeclSpec().getConstexprSpecLoc(),
7503 diag::err_explicit_instantiation_constexpr);
7505 // C++0x [temp.explicit]p2:
7506 // There are two forms of explicit instantiation: an explicit instantiation
7507 // definition and an explicit instantiation declaration. An explicit
7508 // instantiation declaration begins with the extern keyword. [...]
7509 TemplateSpecializationKind TSK
7510 = ExternLoc.isInvalid()? TSK_ExplicitInstantiationDefinition
7511 : TSK_ExplicitInstantiationDeclaration;
7513 LookupResult Previous(*this, NameInfo, LookupOrdinaryName);
7514 LookupParsedName(Previous, S, &D.getCXXScopeSpec());
7516 if (!R->isFunctionType()) {
7517 // C++ [temp.explicit]p1:
7518 // A [...] static data member of a class template can be explicitly
7519 // instantiated from the member definition associated with its class
7521 // C++1y [temp.explicit]p1:
7522 // A [...] variable [...] template specialization can be explicitly
7523 // instantiated from its template.
7524 if (Previous.isAmbiguous())
7527 VarDecl *Prev = Previous.getAsSingle<VarDecl>();
7528 VarTemplateDecl *PrevTemplate = Previous.getAsSingle<VarTemplateDecl>();
7530 if (!PrevTemplate) {
7531 if (!Prev || !Prev->isStaticDataMember()) {
7532 // We expect to see a data data member here.
7533 Diag(D.getIdentifierLoc(), diag::err_explicit_instantiation_not_known)
7535 for (LookupResult::iterator P = Previous.begin(), PEnd = Previous.end();
7537 Diag((*P)->getLocation(), diag::note_explicit_instantiation_here);
7541 if (!Prev->getInstantiatedFromStaticDataMember()) {
7542 // FIXME: Check for explicit specialization?
7543 Diag(D.getIdentifierLoc(),
7544 diag::err_explicit_instantiation_data_member_not_instantiated)
7546 Diag(Prev->getLocation(), diag::note_explicit_instantiation_here);
7547 // FIXME: Can we provide a note showing where this was declared?
7551 // Explicitly instantiate a variable template.
7553 // C++1y [dcl.spec.auto]p6:
7554 // ... A program that uses auto or decltype(auto) in a context not
7555 // explicitly allowed in this section is ill-formed.
7557 // This includes auto-typed variable template instantiations.
7558 if (R->isUndeducedType()) {
7559 Diag(T->getTypeLoc().getLocStart(),
7560 diag::err_auto_not_allowed_var_inst);
7564 if (D.getName().getKind() != UnqualifiedId::IK_TemplateId) {
7565 // C++1y [temp.explicit]p3:
7566 // If the explicit instantiation is for a variable, the unqualified-id
7567 // in the declaration shall be a template-id.
7568 Diag(D.getIdentifierLoc(),
7569 diag::err_explicit_instantiation_without_template_id)
7571 Diag(PrevTemplate->getLocation(),
7572 diag::note_explicit_instantiation_here);
7576 // Translate the parser's template argument list into our AST format.
7577 TemplateArgumentListInfo TemplateArgs =
7578 makeTemplateArgumentListInfo(*this, *D.getName().TemplateId);
7580 DeclResult Res = CheckVarTemplateId(PrevTemplate, TemplateLoc,
7581 D.getIdentifierLoc(), TemplateArgs);
7582 if (Res.isInvalid())
7585 // Ignore access control bits, we don't need them for redeclaration
7587 Prev = cast<VarDecl>(Res.get());
7590 // C++0x [temp.explicit]p2:
7591 // If the explicit instantiation is for a member function, a member class
7592 // or a static data member of a class template specialization, the name of
7593 // the class template specialization in the qualified-id for the member
7594 // name shall be a simple-template-id.
7596 // C++98 has the same restriction, just worded differently.
7598 // This does not apply to variable template specializations, where the
7599 // template-id is in the unqualified-id instead.
7600 if (!ScopeSpecifierHasTemplateId(D.getCXXScopeSpec()) && !PrevTemplate)
7601 Diag(D.getIdentifierLoc(),
7602 diag::ext_explicit_instantiation_without_qualified_id)
7603 << Prev << D.getCXXScopeSpec().getRange();
7605 // Check the scope of this explicit instantiation.
7606 CheckExplicitInstantiationScope(*this, Prev, D.getIdentifierLoc(), true);
7608 // Verify that it is okay to explicitly instantiate here.
7609 TemplateSpecializationKind PrevTSK = Prev->getTemplateSpecializationKind();
7610 SourceLocation POI = Prev->getPointOfInstantiation();
7611 bool HasNoEffect = false;
7612 if (CheckSpecializationInstantiationRedecl(D.getIdentifierLoc(), TSK, Prev,
7613 PrevTSK, POI, HasNoEffect))
7617 // Instantiate static data member or variable template.
7619 Prev->setTemplateSpecializationKind(TSK, D.getIdentifierLoc());
7621 // Merge attributes.
7622 if (AttributeList *Attr = D.getDeclSpec().getAttributes().getList())
7623 ProcessDeclAttributeList(S, Prev, Attr);
7625 if (TSK == TSK_ExplicitInstantiationDefinition)
7626 InstantiateVariableDefinition(D.getIdentifierLoc(), Prev);
7629 // Check the new variable specialization against the parsed input.
7630 if (PrevTemplate && Prev && !Context.hasSameType(Prev->getType(), R)) {
7631 Diag(T->getTypeLoc().getLocStart(),
7632 diag::err_invalid_var_template_spec_type)
7633 << 0 << PrevTemplate << R << Prev->getType();
7634 Diag(PrevTemplate->getLocation(), diag::note_template_declared_here)
7635 << 2 << PrevTemplate->getDeclName();
7639 // FIXME: Create an ExplicitInstantiation node?
7640 return (Decl*) nullptr;
7643 // If the declarator is a template-id, translate the parser's template
7644 // argument list into our AST format.
7645 bool HasExplicitTemplateArgs = false;
7646 TemplateArgumentListInfo TemplateArgs;
7647 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) {
7648 TemplateArgs = makeTemplateArgumentListInfo(*this, *D.getName().TemplateId);
7649 HasExplicitTemplateArgs = true;
7652 // C++ [temp.explicit]p1:
7653 // A [...] function [...] can be explicitly instantiated from its template.
7654 // A member function [...] of a class template can be explicitly
7655 // instantiated from the member definition associated with its class
7657 UnresolvedSet<8> Matches;
7658 TemplateSpecCandidateSet FailedCandidates(D.getIdentifierLoc());
7659 for (LookupResult::iterator P = Previous.begin(), PEnd = Previous.end();
7661 NamedDecl *Prev = *P;
7662 if (!HasExplicitTemplateArgs) {
7663 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Prev)) {
7664 QualType Adjusted = adjustCCAndNoReturn(R, Method->getType());
7665 if (Context.hasSameUnqualifiedType(Method->getType(), Adjusted)) {
7668 Matches.addDecl(Method, P.getAccess());
7669 if (Method->getTemplateSpecializationKind() == TSK_Undeclared)
7675 FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(Prev);
7679 TemplateDeductionInfo Info(FailedCandidates.getLocation());
7680 FunctionDecl *Specialization = nullptr;
7681 if (TemplateDeductionResult TDK
7682 = DeduceTemplateArguments(FunTmpl,
7683 (HasExplicitTemplateArgs ? &TemplateArgs
7685 R, Specialization, Info)) {
7686 // Keep track of almost-matches.
7687 FailedCandidates.addCandidate()
7688 .set(FunTmpl->getTemplatedDecl(),
7689 MakeDeductionFailureInfo(Context, TDK, Info));
7694 Matches.addDecl(Specialization, P.getAccess());
7697 // Find the most specialized function template specialization.
7698 UnresolvedSetIterator Result = getMostSpecialized(
7699 Matches.begin(), Matches.end(), FailedCandidates,
7700 D.getIdentifierLoc(),
7701 PDiag(diag::err_explicit_instantiation_not_known) << Name,
7702 PDiag(diag::err_explicit_instantiation_ambiguous) << Name,
7703 PDiag(diag::note_explicit_instantiation_candidate));
7705 if (Result == Matches.end())
7708 // Ignore access control bits, we don't need them for redeclaration checking.
7709 FunctionDecl *Specialization = cast<FunctionDecl>(*Result);
7711 // C++11 [except.spec]p4
7712 // In an explicit instantiation an exception-specification may be specified,
7713 // but is not required.
7714 // If an exception-specification is specified in an explicit instantiation
7715 // directive, it shall be compatible with the exception-specifications of
7716 // other declarations of that function.
7717 if (auto *FPT = R->getAs<FunctionProtoType>())
7718 if (FPT->hasExceptionSpec()) {
7720 diag::err_mismatched_exception_spec_explicit_instantiation;
7721 if (getLangOpts().MicrosoftExt)
7722 DiagID = diag::ext_mismatched_exception_spec_explicit_instantiation;
7723 bool Result = CheckEquivalentExceptionSpec(
7724 PDiag(DiagID) << Specialization->getType(),
7725 PDiag(diag::note_explicit_instantiation_here),
7726 Specialization->getType()->getAs<FunctionProtoType>(),
7727 Specialization->getLocation(), FPT, D.getLocStart());
7728 // In Microsoft mode, mismatching exception specifications just cause a
7730 if (!getLangOpts().MicrosoftExt && Result)
7734 if (Specialization->getTemplateSpecializationKind() == TSK_Undeclared) {
7735 Diag(D.getIdentifierLoc(),
7736 diag::err_explicit_instantiation_member_function_not_instantiated)
7738 << (Specialization->getTemplateSpecializationKind() ==
7739 TSK_ExplicitSpecialization);
7740 Diag(Specialization->getLocation(), diag::note_explicit_instantiation_here);
7744 FunctionDecl *PrevDecl = Specialization->getPreviousDecl();
7745 if (!PrevDecl && Specialization->isThisDeclarationADefinition())
7746 PrevDecl = Specialization;
7749 bool HasNoEffect = false;
7750 if (CheckSpecializationInstantiationRedecl(D.getIdentifierLoc(), TSK,
7752 PrevDecl->getTemplateSpecializationKind(),
7753 PrevDecl->getPointOfInstantiation(),
7757 // FIXME: We may still want to build some representation of this
7758 // explicit specialization.
7760 return (Decl*) nullptr;
7763 Specialization->setTemplateSpecializationKind(TSK, D.getIdentifierLoc());
7764 AttributeList *Attr = D.getDeclSpec().getAttributes().getList();
7766 ProcessDeclAttributeList(S, Specialization, Attr);
7768 if (Specialization->isDefined()) {
7769 // Let the ASTConsumer know that this function has been explicitly
7770 // instantiated now, and its linkage might have changed.
7771 Consumer.HandleTopLevelDecl(DeclGroupRef(Specialization));
7772 } else if (TSK == TSK_ExplicitInstantiationDefinition)
7773 InstantiateFunctionDefinition(D.getIdentifierLoc(), Specialization);
7775 // C++0x [temp.explicit]p2:
7776 // If the explicit instantiation is for a member function, a member class
7777 // or a static data member of a class template specialization, the name of
7778 // the class template specialization in the qualified-id for the member
7779 // name shall be a simple-template-id.
7781 // C++98 has the same restriction, just worded differently.
7782 FunctionTemplateDecl *FunTmpl = Specialization->getPrimaryTemplate();
7783 if (D.getName().getKind() != UnqualifiedId::IK_TemplateId && !FunTmpl &&
7784 D.getCXXScopeSpec().isSet() &&
7785 !ScopeSpecifierHasTemplateId(D.getCXXScopeSpec()))
7786 Diag(D.getIdentifierLoc(),
7787 diag::ext_explicit_instantiation_without_qualified_id)
7788 << Specialization << D.getCXXScopeSpec().getRange();
7790 CheckExplicitInstantiationScope(*this,
7791 FunTmpl? (NamedDecl *)FunTmpl
7792 : Specialization->getInstantiatedFromMemberFunction(),
7793 D.getIdentifierLoc(),
7794 D.getCXXScopeSpec().isSet());
7796 // FIXME: Create some kind of ExplicitInstantiationDecl here.
7797 return (Decl*) nullptr;
7801 Sema::ActOnDependentTag(Scope *S, unsigned TagSpec, TagUseKind TUK,
7802 const CXXScopeSpec &SS, IdentifierInfo *Name,
7803 SourceLocation TagLoc, SourceLocation NameLoc) {
7804 // This has to hold, because SS is expected to be defined.
7805 assert(Name && "Expected a name in a dependent tag");
7807 NestedNameSpecifier *NNS = SS.getScopeRep();
7811 TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec);
7813 if (TUK == TUK_Declaration || TUK == TUK_Definition) {
7814 Diag(NameLoc, diag::err_dependent_tag_decl)
7815 << (TUK == TUK_Definition) << Kind << SS.getRange();
7819 // Create the resulting type.
7820 ElaboratedTypeKeyword Kwd = TypeWithKeyword::getKeywordForTagTypeKind(Kind);
7821 QualType Result = Context.getDependentNameType(Kwd, NNS, Name);
7823 // Create type-source location information for this type.
7825 DependentNameTypeLoc TL = TLB.push<DependentNameTypeLoc>(Result);
7826 TL.setElaboratedKeywordLoc(TagLoc);
7827 TL.setQualifierLoc(SS.getWithLocInContext(Context));
7828 TL.setNameLoc(NameLoc);
7829 return CreateParsedType(Result, TLB.getTypeSourceInfo(Context, Result));
7833 Sema::ActOnTypenameType(Scope *S, SourceLocation TypenameLoc,
7834 const CXXScopeSpec &SS, const IdentifierInfo &II,
7835 SourceLocation IdLoc) {
7839 if (TypenameLoc.isValid() && S && !S->getTemplateParamParent())
7841 getLangOpts().CPlusPlus11 ?
7842 diag::warn_cxx98_compat_typename_outside_of_template :
7843 diag::ext_typename_outside_of_template)
7844 << FixItHint::CreateRemoval(TypenameLoc);
7846 NestedNameSpecifierLoc QualifierLoc = SS.getWithLocInContext(Context);
7847 QualType T = CheckTypenameType(TypenameLoc.isValid()? ETK_Typename : ETK_None,
7848 TypenameLoc, QualifierLoc, II, IdLoc);
7852 TypeSourceInfo *TSI = Context.CreateTypeSourceInfo(T);
7853 if (isa<DependentNameType>(T)) {
7854 DependentNameTypeLoc TL = TSI->getTypeLoc().castAs<DependentNameTypeLoc>();
7855 TL.setElaboratedKeywordLoc(TypenameLoc);
7856 TL.setQualifierLoc(QualifierLoc);
7857 TL.setNameLoc(IdLoc);
7859 ElaboratedTypeLoc TL = TSI->getTypeLoc().castAs<ElaboratedTypeLoc>();
7860 TL.setElaboratedKeywordLoc(TypenameLoc);
7861 TL.setQualifierLoc(QualifierLoc);
7862 TL.getNamedTypeLoc().castAs<TypeSpecTypeLoc>().setNameLoc(IdLoc);
7865 return CreateParsedType(T, TSI);
7869 Sema::ActOnTypenameType(Scope *S,
7870 SourceLocation TypenameLoc,
7871 const CXXScopeSpec &SS,
7872 SourceLocation TemplateKWLoc,
7873 TemplateTy TemplateIn,
7874 SourceLocation TemplateNameLoc,
7875 SourceLocation LAngleLoc,
7876 ASTTemplateArgsPtr TemplateArgsIn,
7877 SourceLocation RAngleLoc) {
7878 if (TypenameLoc.isValid() && S && !S->getTemplateParamParent())
7880 getLangOpts().CPlusPlus11 ?
7881 diag::warn_cxx98_compat_typename_outside_of_template :
7882 diag::ext_typename_outside_of_template)
7883 << FixItHint::CreateRemoval(TypenameLoc);
7885 // Translate the parser's template argument list in our AST format.
7886 TemplateArgumentListInfo TemplateArgs(LAngleLoc, RAngleLoc);
7887 translateTemplateArguments(TemplateArgsIn, TemplateArgs);
7889 TemplateName Template = TemplateIn.get();
7890 if (DependentTemplateName *DTN = Template.getAsDependentTemplateName()) {
7891 // Construct a dependent template specialization type.
7892 assert(DTN && "dependent template has non-dependent name?");
7893 assert(DTN->getQualifier() == SS.getScopeRep());
7894 QualType T = Context.getDependentTemplateSpecializationType(ETK_Typename,
7895 DTN->getQualifier(),
7896 DTN->getIdentifier(),
7899 // Create source-location information for this type.
7900 TypeLocBuilder Builder;
7901 DependentTemplateSpecializationTypeLoc SpecTL
7902 = Builder.push<DependentTemplateSpecializationTypeLoc>(T);
7903 SpecTL.setElaboratedKeywordLoc(TypenameLoc);
7904 SpecTL.setQualifierLoc(SS.getWithLocInContext(Context));
7905 SpecTL.setTemplateKeywordLoc(TemplateKWLoc);
7906 SpecTL.setTemplateNameLoc(TemplateNameLoc);
7907 SpecTL.setLAngleLoc(LAngleLoc);
7908 SpecTL.setRAngleLoc(RAngleLoc);
7909 for (unsigned I = 0, N = TemplateArgs.size(); I != N; ++I)
7910 SpecTL.setArgLocInfo(I, TemplateArgs[I].getLocInfo());
7911 return CreateParsedType(T, Builder.getTypeSourceInfo(Context, T));
7914 QualType T = CheckTemplateIdType(Template, TemplateNameLoc, TemplateArgs);
7918 // Provide source-location information for the template specialization type.
7919 TypeLocBuilder Builder;
7920 TemplateSpecializationTypeLoc SpecTL
7921 = Builder.push<TemplateSpecializationTypeLoc>(T);
7922 SpecTL.setTemplateKeywordLoc(TemplateKWLoc);
7923 SpecTL.setTemplateNameLoc(TemplateNameLoc);
7924 SpecTL.setLAngleLoc(LAngleLoc);
7925 SpecTL.setRAngleLoc(RAngleLoc);
7926 for (unsigned I = 0, N = TemplateArgs.size(); I != N; ++I)
7927 SpecTL.setArgLocInfo(I, TemplateArgs[I].getLocInfo());
7929 T = Context.getElaboratedType(ETK_Typename, SS.getScopeRep(), T);
7930 ElaboratedTypeLoc TL = Builder.push<ElaboratedTypeLoc>(T);
7931 TL.setElaboratedKeywordLoc(TypenameLoc);
7932 TL.setQualifierLoc(SS.getWithLocInContext(Context));
7934 TypeSourceInfo *TSI = Builder.getTypeSourceInfo(Context, T);
7935 return CreateParsedType(T, TSI);
7939 /// Determine whether this failed name lookup should be treated as being
7940 /// disabled by a usage of std::enable_if.
7941 static bool isEnableIf(NestedNameSpecifierLoc NNS, const IdentifierInfo &II,
7942 SourceRange &CondRange) {
7943 // We must be looking for a ::type...
7944 if (!II.isStr("type"))
7947 // ... within an explicitly-written template specialization...
7948 if (!NNS || !NNS.getNestedNameSpecifier()->getAsType())
7950 TypeLoc EnableIfTy = NNS.getTypeLoc();
7951 TemplateSpecializationTypeLoc EnableIfTSTLoc =
7952 EnableIfTy.getAs<TemplateSpecializationTypeLoc>();
7953 if (!EnableIfTSTLoc || EnableIfTSTLoc.getNumArgs() == 0)
7955 const TemplateSpecializationType *EnableIfTST =
7956 cast<TemplateSpecializationType>(EnableIfTSTLoc.getTypePtr());
7958 // ... which names a complete class template declaration...
7959 const TemplateDecl *EnableIfDecl =
7960 EnableIfTST->getTemplateName().getAsTemplateDecl();
7961 if (!EnableIfDecl || EnableIfTST->isIncompleteType())
7964 // ... called "enable_if".
7965 const IdentifierInfo *EnableIfII =
7966 EnableIfDecl->getDeclName().getAsIdentifierInfo();
7967 if (!EnableIfII || !EnableIfII->isStr("enable_if"))
7970 // Assume the first template argument is the condition.
7971 CondRange = EnableIfTSTLoc.getArgLoc(0).getSourceRange();
7975 /// \brief Build the type that describes a C++ typename specifier,
7976 /// e.g., "typename T::type".
7978 Sema::CheckTypenameType(ElaboratedTypeKeyword Keyword,
7979 SourceLocation KeywordLoc,
7980 NestedNameSpecifierLoc QualifierLoc,
7981 const IdentifierInfo &II,
7982 SourceLocation IILoc) {
7984 SS.Adopt(QualifierLoc);
7986 DeclContext *Ctx = computeDeclContext(SS);
7988 // If the nested-name-specifier is dependent and couldn't be
7989 // resolved to a type, build a typename type.
7990 assert(QualifierLoc.getNestedNameSpecifier()->isDependent());
7991 return Context.getDependentNameType(Keyword,
7992 QualifierLoc.getNestedNameSpecifier(),
7996 // If the nested-name-specifier refers to the current instantiation,
7997 // the "typename" keyword itself is superfluous. In C++03, the
7998 // program is actually ill-formed. However, DR 382 (in C++0x CD1)
7999 // allows such extraneous "typename" keywords, and we retroactively
8000 // apply this DR to C++03 code with only a warning. In any case we continue.
8002 if (RequireCompleteDeclContext(SS, Ctx))
8005 DeclarationName Name(&II);
8006 LookupResult Result(*this, Name, IILoc, LookupOrdinaryName);
8007 LookupQualifiedName(Result, Ctx, SS);
8008 unsigned DiagID = 0;
8009 Decl *Referenced = nullptr;
8010 switch (Result.getResultKind()) {
8011 case LookupResult::NotFound: {
8012 // If we're looking up 'type' within a template named 'enable_if', produce
8013 // a more specific diagnostic.
8014 SourceRange CondRange;
8015 if (isEnableIf(QualifierLoc, II, CondRange)) {
8016 Diag(CondRange.getBegin(), diag::err_typename_nested_not_found_enable_if)
8017 << Ctx << CondRange;
8021 DiagID = diag::err_typename_nested_not_found;
8025 case LookupResult::FoundUnresolvedValue: {
8026 // We found a using declaration that is a value. Most likely, the using
8027 // declaration itself is meant to have the 'typename' keyword.
8028 SourceRange FullRange(KeywordLoc.isValid() ? KeywordLoc : SS.getBeginLoc(),
8030 Diag(IILoc, diag::err_typename_refers_to_using_value_decl)
8031 << Name << Ctx << FullRange;
8032 if (UnresolvedUsingValueDecl *Using
8033 = dyn_cast<UnresolvedUsingValueDecl>(Result.getRepresentativeDecl())){
8034 SourceLocation Loc = Using->getQualifierLoc().getBeginLoc();
8035 Diag(Loc, diag::note_using_value_decl_missing_typename)
8036 << FixItHint::CreateInsertion(Loc, "typename ");
8039 // Fall through to create a dependent typename type, from which we can recover
8042 case LookupResult::NotFoundInCurrentInstantiation:
8043 // Okay, it's a member of an unknown instantiation.
8044 return Context.getDependentNameType(Keyword,
8045 QualifierLoc.getNestedNameSpecifier(),
8048 case LookupResult::Found:
8049 if (TypeDecl *Type = dyn_cast<TypeDecl>(Result.getFoundDecl())) {
8050 // We found a type. Build an ElaboratedType, since the
8051 // typename-specifier was just sugar.
8052 MarkAnyDeclReferenced(Type->getLocation(), Type, /*OdrUse=*/false);
8053 return Context.getElaboratedType(ETK_Typename,
8054 QualifierLoc.getNestedNameSpecifier(),
8055 Context.getTypeDeclType(Type));
8058 DiagID = diag::err_typename_nested_not_type;
8059 Referenced = Result.getFoundDecl();
8062 case LookupResult::FoundOverloaded:
8063 DiagID = diag::err_typename_nested_not_type;
8064 Referenced = *Result.begin();
8067 case LookupResult::Ambiguous:
8071 // If we get here, it's because name lookup did not find a
8072 // type. Emit an appropriate diagnostic and return an error.
8073 SourceRange FullRange(KeywordLoc.isValid() ? KeywordLoc : SS.getBeginLoc(),
8075 Diag(IILoc, DiagID) << FullRange << Name << Ctx;
8077 Diag(Referenced->getLocation(), diag::note_typename_refers_here)
8083 // See Sema::RebuildTypeInCurrentInstantiation
8084 class CurrentInstantiationRebuilder
8085 : public TreeTransform<CurrentInstantiationRebuilder> {
8087 DeclarationName Entity;
8090 typedef TreeTransform<CurrentInstantiationRebuilder> inherited;
8092 CurrentInstantiationRebuilder(Sema &SemaRef,
8094 DeclarationName Entity)
8095 : TreeTransform<CurrentInstantiationRebuilder>(SemaRef),
8096 Loc(Loc), Entity(Entity) { }
8098 /// \brief Determine whether the given type \p T has already been
8101 /// For the purposes of type reconstruction, a type has already been
8102 /// transformed if it is NULL or if it is not dependent.
8103 bool AlreadyTransformed(QualType T) {
8104 return T.isNull() || !T->isDependentType();
8107 /// \brief Returns the location of the entity whose type is being
8109 SourceLocation getBaseLocation() { return Loc; }
8111 /// \brief Returns the name of the entity whose type is being rebuilt.
8112 DeclarationName getBaseEntity() { return Entity; }
8114 /// \brief Sets the "base" location and entity when that
8115 /// information is known based on another transformation.
8116 void setBase(SourceLocation Loc, DeclarationName Entity) {
8118 this->Entity = Entity;
8121 ExprResult TransformLambdaExpr(LambdaExpr *E) {
8122 // Lambdas never need to be transformed.
8128 /// \brief Rebuilds a type within the context of the current instantiation.
8130 /// The type \p T is part of the type of an out-of-line member definition of
8131 /// a class template (or class template partial specialization) that was parsed
8132 /// and constructed before we entered the scope of the class template (or
8133 /// partial specialization thereof). This routine will rebuild that type now
8134 /// that we have entered the declarator's scope, which may produce different
8135 /// canonical types, e.g.,
8138 /// template<typename T>
8140 /// typedef T* pointer;
8144 /// template<typename T>
8145 /// typename X<T>::pointer X<T>::data() { ... }
8148 /// Here, the type "typename X<T>::pointer" will be created as a DependentNameType,
8149 /// since we do not know that we can look into X<T> when we parsed the type.
8150 /// This function will rebuild the type, performing the lookup of "pointer"
8151 /// in X<T> and returning an ElaboratedType whose canonical type is the same
8152 /// as the canonical type of T*, allowing the return types of the out-of-line
8153 /// definition and the declaration to match.
8154 TypeSourceInfo *Sema::RebuildTypeInCurrentInstantiation(TypeSourceInfo *T,
8156 DeclarationName Name) {
8157 if (!T || !T->getType()->isDependentType())
8160 CurrentInstantiationRebuilder Rebuilder(*this, Loc, Name);
8161 return Rebuilder.TransformType(T);
8164 ExprResult Sema::RebuildExprInCurrentInstantiation(Expr *E) {
8165 CurrentInstantiationRebuilder Rebuilder(*this, E->getExprLoc(),
8167 return Rebuilder.TransformExpr(E);
8170 bool Sema::RebuildNestedNameSpecifierInCurrentInstantiation(CXXScopeSpec &SS) {
8174 NestedNameSpecifierLoc QualifierLoc = SS.getWithLocInContext(Context);
8175 CurrentInstantiationRebuilder Rebuilder(*this, SS.getRange().getBegin(),
8177 NestedNameSpecifierLoc Rebuilt
8178 = Rebuilder.TransformNestedNameSpecifierLoc(QualifierLoc);
8186 /// \brief Rebuild the template parameters now that we know we're in a current
8188 bool Sema::RebuildTemplateParamsInCurrentInstantiation(
8189 TemplateParameterList *Params) {
8190 for (unsigned I = 0, N = Params->size(); I != N; ++I) {
8191 Decl *Param = Params->getParam(I);
8193 // There is nothing to rebuild in a type parameter.
8194 if (isa<TemplateTypeParmDecl>(Param))
8197 // Rebuild the template parameter list of a template template parameter.
8198 if (TemplateTemplateParmDecl *TTP
8199 = dyn_cast<TemplateTemplateParmDecl>(Param)) {
8200 if (RebuildTemplateParamsInCurrentInstantiation(
8201 TTP->getTemplateParameters()))
8207 // Rebuild the type of a non-type template parameter.
8208 NonTypeTemplateParmDecl *NTTP = cast<NonTypeTemplateParmDecl>(Param);
8209 TypeSourceInfo *NewTSI
8210 = RebuildTypeInCurrentInstantiation(NTTP->getTypeSourceInfo(),
8211 NTTP->getLocation(),
8212 NTTP->getDeclName());
8216 if (NewTSI != NTTP->getTypeSourceInfo()) {
8217 NTTP->setTypeSourceInfo(NewTSI);
8218 NTTP->setType(NewTSI->getType());
8225 /// \brief Produces a formatted string that describes the binding of
8226 /// template parameters to template arguments.
8228 Sema::getTemplateArgumentBindingsText(const TemplateParameterList *Params,
8229 const TemplateArgumentList &Args) {
8230 return getTemplateArgumentBindingsText(Params, Args.data(), Args.size());
8234 Sema::getTemplateArgumentBindingsText(const TemplateParameterList *Params,
8235 const TemplateArgument *Args,
8237 SmallString<128> Str;
8238 llvm::raw_svector_ostream Out(Str);
8240 if (!Params || Params->size() == 0 || NumArgs == 0)
8241 return std::string();
8243 for (unsigned I = 0, N = Params->size(); I != N; ++I) {
8252 if (const IdentifierInfo *Id = Params->getParam(I)->getIdentifier()) {
8253 Out << Id->getName();
8259 Args[I].print(getPrintingPolicy(), Out);
8266 void Sema::MarkAsLateParsedTemplate(FunctionDecl *FD, Decl *FnD,
8267 CachedTokens &Toks) {
8271 LateParsedTemplate *LPT = new LateParsedTemplate;
8273 // Take tokens to avoid allocations
8274 LPT->Toks.swap(Toks);
8276 LateParsedTemplateMap[FD] = LPT;
8278 FD->setLateTemplateParsed(true);
8281 void Sema::UnmarkAsLateParsedTemplate(FunctionDecl *FD) {
8284 FD->setLateTemplateParsed(false);
8287 bool Sema::IsInsideALocalClassWithinATemplateFunction() {
8288 DeclContext *DC = CurContext;
8291 if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(CurContext)) {
8292 const FunctionDecl *FD = RD->isLocalClass();
8293 return (FD && FD->getTemplatedKind() != FunctionDecl::TK_NonTemplate);
8294 } else if (DC->isTranslationUnit() || DC->isNamespace())
8297 DC = DC->getParent();