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 //===----------------------------------------------------------------------===/
14 #include "TreeTransform.h"
15 #include "clang/AST/ASTContext.h"
16 #include "clang/AST/Expr.h"
17 #include "clang/AST/ExprCXX.h"
18 #include "clang/AST/DeclFriend.h"
19 #include "clang/AST/DeclTemplate.h"
20 #include "clang/Parse/DeclSpec.h"
21 #include "clang/Parse/Template.h"
22 #include "clang/Basic/LangOptions.h"
23 #include "clang/Basic/PartialDiagnostic.h"
24 #include "llvm/ADT/StringExtras.h"
25 using namespace clang;
27 /// \brief Determine whether the declaration found is acceptable as the name
28 /// of a template and, if so, return that template declaration. Otherwise,
30 static NamedDecl *isAcceptableTemplateName(ASTContext &Context,
32 NamedDecl *D = Orig->getUnderlyingDecl();
34 if (isa<TemplateDecl>(D))
37 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(D)) {
38 // C++ [temp.local]p1:
39 // Like normal (non-template) classes, class templates have an
40 // injected-class-name (Clause 9). The injected-class-name
41 // can be used with or without a template-argument-list. When
42 // it is used without a template-argument-list, it is
43 // equivalent to the injected-class-name followed by the
44 // template-parameters of the class template enclosed in
45 // <>. When it is used with a template-argument-list, it
46 // refers to the specified class template specialization,
47 // which could be the current specialization or another
49 if (Record->isInjectedClassName()) {
50 Record = cast<CXXRecordDecl>(Record->getDeclContext());
51 if (Record->getDescribedClassTemplate())
52 return Record->getDescribedClassTemplate();
54 if (ClassTemplateSpecializationDecl *Spec
55 = dyn_cast<ClassTemplateSpecializationDecl>(Record))
56 return Spec->getSpecializedTemplate();
65 static void FilterAcceptableTemplateNames(ASTContext &C, LookupResult &R) {
66 // The set of class templates we've already seen.
67 llvm::SmallPtrSet<ClassTemplateDecl *, 8> ClassTemplates;
68 LookupResult::Filter filter = R.makeFilter();
69 while (filter.hasNext()) {
70 NamedDecl *Orig = filter.next();
71 NamedDecl *Repl = isAcceptableTemplateName(C, Orig);
74 else if (Repl != Orig) {
76 // C++ [temp.local]p3:
77 // A lookup that finds an injected-class-name (10.2) can result in an
78 // ambiguity in certain cases (for example, if it is found in more than
79 // one base class). If all of the injected-class-names that are found
80 // refer to specializations of the same class template, and if the name
81 // is followed by a template-argument-list, the reference refers to the
82 // class template itself and not a specialization thereof, and is not
85 // FIXME: Will we eventually have to do the same for alias templates?
86 if (ClassTemplateDecl *ClassTmpl = dyn_cast<ClassTemplateDecl>(Repl))
87 if (!ClassTemplates.insert(ClassTmpl)) {
98 TemplateNameKind Sema::isTemplateName(Scope *S,
101 TypeTy *ObjectTypePtr,
102 bool EnteringContext,
103 TemplateTy &TemplateResult,
104 bool &MemberOfUnknownSpecialization) {
105 assert(getLangOptions().CPlusPlus && "No template names in C!");
107 DeclarationName TName;
108 MemberOfUnknownSpecialization = false;
110 switch (Name.getKind()) {
111 case UnqualifiedId::IK_Identifier:
112 TName = DeclarationName(Name.Identifier);
115 case UnqualifiedId::IK_OperatorFunctionId:
116 TName = Context.DeclarationNames.getCXXOperatorName(
117 Name.OperatorFunctionId.Operator);
120 case UnqualifiedId::IK_LiteralOperatorId:
121 TName = Context.DeclarationNames.getCXXLiteralOperatorName(Name.Identifier);
125 return TNK_Non_template;
128 QualType ObjectType = QualType::getFromOpaquePtr(ObjectTypePtr);
130 LookupResult R(*this, TName, Name.getSourceRange().getBegin(),
132 R.suppressDiagnostics();
133 LookupTemplateName(R, S, SS, ObjectType, EnteringContext,
134 MemberOfUnknownSpecialization);
135 if (R.empty() || R.isAmbiguous())
136 return TNK_Non_template;
138 TemplateName Template;
139 TemplateNameKind TemplateKind;
141 unsigned ResultCount = R.end() - R.begin();
142 if (ResultCount > 1) {
143 // We assume that we'll preserve the qualifier from a function
144 // template name in other ways.
145 Template = Context.getOverloadedTemplateName(R.begin(), R.end());
146 TemplateKind = TNK_Function_template;
148 TemplateDecl *TD = cast<TemplateDecl>((*R.begin())->getUnderlyingDecl());
150 if (SS.isSet() && !SS.isInvalid()) {
151 NestedNameSpecifier *Qualifier
152 = static_cast<NestedNameSpecifier *>(SS.getScopeRep());
153 Template = Context.getQualifiedTemplateName(Qualifier, false, TD);
155 Template = TemplateName(TD);
158 if (isa<FunctionTemplateDecl>(TD))
159 TemplateKind = TNK_Function_template;
161 assert(isa<ClassTemplateDecl>(TD) || isa<TemplateTemplateParmDecl>(TD));
162 TemplateKind = TNK_Type_template;
166 TemplateResult = TemplateTy::make(Template);
170 bool Sema::DiagnoseUnknownTemplateName(const IdentifierInfo &II,
171 SourceLocation IILoc,
173 const CXXScopeSpec *SS,
174 TemplateTy &SuggestedTemplate,
175 TemplateNameKind &SuggestedKind) {
176 // We can't recover unless there's a dependent scope specifier preceding the
178 // FIXME: Typo correction?
179 if (!SS || !SS->isSet() || !isDependentScopeSpecifier(*SS) ||
180 computeDeclContext(*SS))
183 // The code is missing a 'template' keyword prior to the dependent template
185 NestedNameSpecifier *Qualifier = (NestedNameSpecifier*)SS->getScopeRep();
186 Diag(IILoc, diag::err_template_kw_missing)
187 << Qualifier << II.getName()
188 << FixItHint::CreateInsertion(IILoc, "template ");
190 = TemplateTy::make(Context.getDependentTemplateName(Qualifier, &II));
191 SuggestedKind = TNK_Dependent_template_name;
195 void Sema::LookupTemplateName(LookupResult &Found,
196 Scope *S, CXXScopeSpec &SS,
198 bool EnteringContext,
199 bool &MemberOfUnknownSpecialization) {
200 // Determine where to perform name lookup
201 MemberOfUnknownSpecialization = false;
202 DeclContext *LookupCtx = 0;
203 bool isDependent = false;
204 if (!ObjectType.isNull()) {
205 // This nested-name-specifier occurs in a member access expression, e.g.,
206 // x->B::f, and we are looking into the type of the object.
207 assert(!SS.isSet() && "ObjectType and scope specifier cannot coexist");
208 LookupCtx = computeDeclContext(ObjectType);
209 isDependent = ObjectType->isDependentType();
210 assert((isDependent || !ObjectType->isIncompleteType()) &&
211 "Caller should have completed object type");
212 } else if (SS.isSet()) {
213 // This nested-name-specifier occurs after another nested-name-specifier,
214 // so long into the context associated with the prior nested-name-specifier.
215 LookupCtx = computeDeclContext(SS, EnteringContext);
216 isDependent = isDependentScopeSpecifier(SS);
218 // The declaration context must be complete.
219 if (LookupCtx && RequireCompleteDeclContext(SS, LookupCtx))
223 bool ObjectTypeSearchedInScope = false;
225 // Perform "qualified" name lookup into the declaration context we
226 // computed, which is either the type of the base of a member access
227 // expression or the declaration context associated with a prior
228 // nested-name-specifier.
229 LookupQualifiedName(Found, LookupCtx);
231 if (!ObjectType.isNull() && Found.empty()) {
232 // C++ [basic.lookup.classref]p1:
233 // In a class member access expression (5.2.5), if the . or -> token is
234 // immediately followed by an identifier followed by a <, the
235 // identifier must be looked up to determine whether the < is the
236 // beginning of a template argument list (14.2) or a less-than operator.
237 // The identifier is first looked up in the class of the object
238 // expression. If the identifier is not found, it is then looked up in
239 // the context of the entire postfix-expression and shall name a class
240 // or function template.
242 // FIXME: When we're instantiating a template, do we actually have to
243 // look in the scope of the template? Seems fishy...
244 if (S) LookupName(Found, S);
245 ObjectTypeSearchedInScope = true;
247 } else if (isDependent) {
248 // We cannot look into a dependent object type or nested nme
250 MemberOfUnknownSpecialization = true;
253 // Perform unqualified name lookup in the current scope.
254 LookupName(Found, S);
257 if (Found.empty() && !isDependent) {
258 // If we did not find any names, attempt to correct any typos.
259 DeclarationName Name = Found.getLookupName();
260 if (DeclarationName Corrected = CorrectTypo(Found, S, &SS, LookupCtx,
261 false, CTC_CXXCasts)) {
262 FilterAcceptableTemplateNames(Context, Found);
263 if (!Found.empty()) {
265 Diag(Found.getNameLoc(), diag::err_no_member_template_suggest)
266 << Name << LookupCtx << Found.getLookupName() << SS.getRange()
267 << FixItHint::CreateReplacement(Found.getNameLoc(),
268 Found.getLookupName().getAsString());
270 Diag(Found.getNameLoc(), diag::err_no_template_suggest)
271 << Name << Found.getLookupName()
272 << FixItHint::CreateReplacement(Found.getNameLoc(),
273 Found.getLookupName().getAsString());
274 if (TemplateDecl *Template = Found.getAsSingle<TemplateDecl>())
275 Diag(Template->getLocation(), diag::note_previous_decl)
276 << Template->getDeclName();
280 Found.setLookupName(Name);
284 FilterAcceptableTemplateNames(Context, Found);
288 if (S && !ObjectType.isNull() && !ObjectTypeSearchedInScope) {
289 // C++ [basic.lookup.classref]p1:
290 // [...] If the lookup in the class of the object expression finds a
291 // template, the name is also looked up in the context of the entire
292 // postfix-expression and [...]
294 LookupResult FoundOuter(*this, Found.getLookupName(), Found.getNameLoc(),
296 LookupName(FoundOuter, S);
297 FilterAcceptableTemplateNames(Context, FoundOuter);
299 if (FoundOuter.empty()) {
300 // - if the name is not found, the name found in the class of the
301 // object expression is used, otherwise
302 } else if (!FoundOuter.getAsSingle<ClassTemplateDecl>()) {
303 // - if the name is found in the context of the entire
304 // postfix-expression and does not name a class template, the name
305 // found in the class of the object expression is used, otherwise
306 } else if (!Found.isSuppressingDiagnostics()) {
307 // - if the name found is a class template, it must refer to the same
308 // entity as the one found in the class of the object expression,
309 // otherwise the program is ill-formed.
310 if (!Found.isSingleResult() ||
311 Found.getFoundDecl()->getCanonicalDecl()
312 != FoundOuter.getFoundDecl()->getCanonicalDecl()) {
313 Diag(Found.getNameLoc(),
314 diag::ext_nested_name_member_ref_lookup_ambiguous)
315 << Found.getLookupName()
317 Diag(Found.getRepresentativeDecl()->getLocation(),
318 diag::note_ambig_member_ref_object_type)
320 Diag(FoundOuter.getFoundDecl()->getLocation(),
321 diag::note_ambig_member_ref_scope);
323 // Recover by taking the template that we found in the object
324 // expression's type.
330 /// ActOnDependentIdExpression - Handle a dependent id-expression that
331 /// was just parsed. This is only possible with an explicit scope
332 /// specifier naming a dependent type.
333 Sema::OwningExprResult
334 Sema::ActOnDependentIdExpression(const CXXScopeSpec &SS,
335 DeclarationName Name,
336 SourceLocation NameLoc,
337 bool isAddressOfOperand,
338 const TemplateArgumentListInfo *TemplateArgs) {
339 NestedNameSpecifier *Qualifier
340 = static_cast<NestedNameSpecifier*>(SS.getScopeRep());
342 DeclContext *DC = getFunctionLevelDeclContext();
344 if (!isAddressOfOperand &&
345 isa<CXXMethodDecl>(DC) &&
346 cast<CXXMethodDecl>(DC)->isInstance()) {
347 QualType ThisType = cast<CXXMethodDecl>(DC)->getThisType(Context);
349 // Since the 'this' expression is synthesized, we don't need to
350 // perform the double-lookup check.
351 NamedDecl *FirstQualifierInScope = 0;
353 return Owned(CXXDependentScopeMemberExpr::Create(Context,
354 /*This*/ 0, ThisType,
356 /*Op*/ SourceLocation(),
357 Qualifier, SS.getRange(),
358 FirstQualifierInScope,
363 return BuildDependentDeclRefExpr(SS, Name, NameLoc, TemplateArgs);
366 Sema::OwningExprResult
367 Sema::BuildDependentDeclRefExpr(const CXXScopeSpec &SS,
368 DeclarationName Name,
369 SourceLocation NameLoc,
370 const TemplateArgumentListInfo *TemplateArgs) {
371 return Owned(DependentScopeDeclRefExpr::Create(Context,
372 static_cast<NestedNameSpecifier*>(SS.getScopeRep()),
378 /// DiagnoseTemplateParameterShadow - Produce a diagnostic complaining
379 /// that the template parameter 'PrevDecl' is being shadowed by a new
380 /// declaration at location Loc. Returns true to indicate that this is
381 /// an error, and false otherwise.
382 bool Sema::DiagnoseTemplateParameterShadow(SourceLocation Loc, Decl *PrevDecl) {
383 assert(PrevDecl->isTemplateParameter() && "Not a template parameter");
385 // Microsoft Visual C++ permits template parameters to be shadowed.
386 if (getLangOptions().Microsoft)
389 // C++ [temp.local]p4:
390 // A template-parameter shall not be redeclared within its
391 // scope (including nested scopes).
392 Diag(Loc, diag::err_template_param_shadow)
393 << cast<NamedDecl>(PrevDecl)->getDeclName();
394 Diag(PrevDecl->getLocation(), diag::note_template_param_here);
398 /// AdjustDeclIfTemplate - If the given decl happens to be a template, reset
399 /// the parameter D to reference the templated declaration and return a pointer
400 /// to the template declaration. Otherwise, do nothing to D and return null.
401 TemplateDecl *Sema::AdjustDeclIfTemplate(DeclPtrTy &D) {
402 if (TemplateDecl *Temp = dyn_cast_or_null<TemplateDecl>(D.getAs<Decl>())) {
403 D = DeclPtrTy::make(Temp->getTemplatedDecl());
409 static TemplateArgumentLoc translateTemplateArgument(Sema &SemaRef,
410 const ParsedTemplateArgument &Arg) {
412 switch (Arg.getKind()) {
413 case ParsedTemplateArgument::Type: {
415 QualType T = SemaRef.GetTypeFromParser(Arg.getAsType(), &DI);
417 DI = SemaRef.Context.getTrivialTypeSourceInfo(T, Arg.getLocation());
418 return TemplateArgumentLoc(TemplateArgument(T), DI);
421 case ParsedTemplateArgument::NonType: {
422 Expr *E = static_cast<Expr *>(Arg.getAsExpr());
423 return TemplateArgumentLoc(TemplateArgument(E), E);
426 case ParsedTemplateArgument::Template: {
427 TemplateName Template
428 = TemplateName::getFromVoidPointer(Arg.getAsTemplate().get());
429 return TemplateArgumentLoc(TemplateArgument(Template),
430 Arg.getScopeSpec().getRange(),
435 llvm_unreachable("Unhandled parsed template argument");
436 return TemplateArgumentLoc();
439 /// \brief Translates template arguments as provided by the parser
440 /// into template arguments used by semantic analysis.
441 void Sema::translateTemplateArguments(const ASTTemplateArgsPtr &TemplateArgsIn,
442 TemplateArgumentListInfo &TemplateArgs) {
443 for (unsigned I = 0, Last = TemplateArgsIn.size(); I != Last; ++I)
444 TemplateArgs.addArgument(translateTemplateArgument(*this,
448 /// ActOnTypeParameter - Called when a C++ template type parameter
449 /// (e.g., "typename T") has been parsed. Typename specifies whether
450 /// the keyword "typename" was used to declare the type parameter
451 /// (otherwise, "class" was used), and KeyLoc is the location of the
452 /// "class" or "typename" keyword. ParamName is the name of the
453 /// parameter (NULL indicates an unnamed template parameter) and
454 /// ParamName is the location of the parameter name (if any).
455 /// If the type parameter has a default argument, it will be added
456 /// later via ActOnTypeParameterDefault.
457 Sema::DeclPtrTy Sema::ActOnTypeParameter(Scope *S, bool Typename, bool Ellipsis,
458 SourceLocation EllipsisLoc,
459 SourceLocation KeyLoc,
460 IdentifierInfo *ParamName,
461 SourceLocation ParamNameLoc,
462 unsigned Depth, unsigned Position,
463 SourceLocation EqualLoc,
464 TypeTy *DefaultArg) {
465 assert(S->isTemplateParamScope() &&
466 "Template type parameter not in template parameter scope!");
467 bool Invalid = false;
470 NamedDecl *PrevDecl = LookupSingleName(S, ParamName, ParamNameLoc,
473 if (PrevDecl && PrevDecl->isTemplateParameter())
474 Invalid = Invalid || DiagnoseTemplateParameterShadow(ParamNameLoc,
478 SourceLocation Loc = ParamNameLoc;
482 TemplateTypeParmDecl *Param
483 = TemplateTypeParmDecl::Create(Context, Context.getTranslationUnitDecl(),
484 Loc, Depth, Position, ParamName, Typename,
487 Param->setInvalidDecl();
490 // Add the template parameter into the current scope.
491 S->AddDecl(DeclPtrTy::make(Param));
492 IdResolver.AddDecl(Param);
495 // Handle the default argument, if provided.
497 TypeSourceInfo *DefaultTInfo;
498 GetTypeFromParser(DefaultArg, &DefaultTInfo);
500 assert(DefaultTInfo && "expected source information for type");
502 // C++0x [temp.param]p9:
503 // A default template-argument may be specified for any kind of
504 // template-parameter that is not a template parameter pack.
506 Diag(EqualLoc, diag::err_template_param_pack_default_arg);
507 return DeclPtrTy::make(Param);
510 // Check the template argument itself.
511 if (CheckTemplateArgument(Param, DefaultTInfo)) {
512 Param->setInvalidDecl();
513 return DeclPtrTy::make(Param);;
516 Param->setDefaultArgument(DefaultTInfo, false);
519 return DeclPtrTy::make(Param);
522 /// \brief Check that the type of a non-type template parameter is
525 /// \returns the (possibly-promoted) parameter type if valid;
526 /// otherwise, produces a diagnostic and returns a NULL type.
528 Sema::CheckNonTypeTemplateParameterType(QualType T, SourceLocation Loc) {
529 // We don't allow variably-modified types as the type of non-type template
531 if (T->isVariablyModifiedType()) {
532 Diag(Loc, diag::err_variably_modified_nontype_template_param)
537 // C++ [temp.param]p4:
539 // A non-type template-parameter shall have one of the following
540 // (optionally cv-qualified) types:
542 // -- integral or enumeration type,
543 if (T->isIntegralOrEnumerationType() ||
544 // -- pointer to object or pointer to function,
545 (T->isPointerType() &&
546 (T->getAs<PointerType>()->getPointeeType()->isObjectType() ||
547 T->getAs<PointerType>()->getPointeeType()->isFunctionType())) ||
548 // -- reference to object or reference to function,
549 T->isReferenceType() ||
550 // -- pointer to member.
551 T->isMemberPointerType() ||
552 // If T is a dependent type, we can't do the check now, so we
553 // assume that it is well-formed.
554 T->isDependentType())
556 // C++ [temp.param]p8:
558 // A non-type template-parameter of type "array of T" or
559 // "function returning T" is adjusted to be of type "pointer to
560 // T" or "pointer to function returning T", respectively.
561 else if (T->isArrayType())
562 // FIXME: Keep the type prior to promotion?
563 return Context.getArrayDecayedType(T);
564 else if (T->isFunctionType())
565 // FIXME: Keep the type prior to promotion?
566 return Context.getPointerType(T);
568 Diag(Loc, diag::err_template_nontype_parm_bad_type)
574 Sema::DeclPtrTy Sema::ActOnNonTypeTemplateParameter(Scope *S, Declarator &D,
577 SourceLocation EqualLoc,
578 ExprArg DefaultArg) {
579 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S);
580 QualType T = TInfo->getType();
582 assert(S->isTemplateParamScope() &&
583 "Non-type template parameter not in template parameter scope!");
584 bool Invalid = false;
586 IdentifierInfo *ParamName = D.getIdentifier();
588 NamedDecl *PrevDecl = LookupSingleName(S, ParamName, D.getIdentifierLoc(),
591 if (PrevDecl && PrevDecl->isTemplateParameter())
592 Invalid = Invalid || DiagnoseTemplateParameterShadow(D.getIdentifierLoc(),
596 T = CheckNonTypeTemplateParameterType(T, D.getIdentifierLoc());
598 T = Context.IntTy; // Recover with an 'int' type.
602 NonTypeTemplateParmDecl *Param
603 = NonTypeTemplateParmDecl::Create(Context, Context.getTranslationUnitDecl(),
604 D.getIdentifierLoc(),
605 Depth, Position, ParamName, T, TInfo);
607 Param->setInvalidDecl();
609 if (D.getIdentifier()) {
610 // Add the template parameter into the current scope.
611 S->AddDecl(DeclPtrTy::make(Param));
612 IdResolver.AddDecl(Param);
615 // Check the well-formedness of the default template argument, if provided.
616 if (Expr *Default = static_cast<Expr *>(DefaultArg.get())) {
617 TemplateArgument Converted;
618 if (CheckTemplateArgument(Param, Param->getType(), Default, Converted)) {
619 Param->setInvalidDecl();
620 return DeclPtrTy::make(Param);;
623 Param->setDefaultArgument(DefaultArg.takeAs<Expr>(), false);
626 return DeclPtrTy::make(Param);
629 /// ActOnTemplateTemplateParameter - Called when a C++ template template
630 /// parameter (e.g. T in template <template <typename> class T> class array)
631 /// has been parsed. S is the current scope.
632 Sema::DeclPtrTy Sema::ActOnTemplateTemplateParameter(Scope* S,
633 SourceLocation TmpLoc,
634 TemplateParamsTy *Params,
635 IdentifierInfo *Name,
636 SourceLocation NameLoc,
639 SourceLocation EqualLoc,
640 const ParsedTemplateArgument &Default) {
641 assert(S->isTemplateParamScope() &&
642 "Template template parameter not in template parameter scope!");
644 // Construct the parameter object.
645 TemplateTemplateParmDecl *Param =
646 TemplateTemplateParmDecl::Create(Context, Context.getTranslationUnitDecl(),
647 TmpLoc, Depth, Position, Name,
648 (TemplateParameterList*)Params);
650 // If the template template parameter has a name, then link the identifier
651 // into the scope and lookup mechanisms.
653 S->AddDecl(DeclPtrTy::make(Param));
654 IdResolver.AddDecl(Param);
657 if (!Default.isInvalid()) {
658 // Check only that we have a template template argument. We don't want to
659 // try to check well-formedness now, because our template template parameter
660 // might have dependent types in its template parameters, which we wouldn't
661 // be able to match now.
663 // If none of the template template parameter's template arguments mention
664 // other template parameters, we could actually perform more checking here.
665 // However, it isn't worth doing.
666 TemplateArgumentLoc DefaultArg = translateTemplateArgument(*this, Default);
667 if (DefaultArg.getArgument().getAsTemplate().isNull()) {
668 Diag(DefaultArg.getLocation(), diag::err_template_arg_not_class_template)
669 << DefaultArg.getSourceRange();
670 return DeclPtrTy::make(Param);
673 Param->setDefaultArgument(DefaultArg, false);
676 return DeclPtrTy::make(Param);
679 /// ActOnTemplateParameterList - Builds a TemplateParameterList that
680 /// contains the template parameters in Params/NumParams.
681 Sema::TemplateParamsTy *
682 Sema::ActOnTemplateParameterList(unsigned Depth,
683 SourceLocation ExportLoc,
684 SourceLocation TemplateLoc,
685 SourceLocation LAngleLoc,
686 DeclPtrTy *Params, unsigned NumParams,
687 SourceLocation RAngleLoc) {
688 if (ExportLoc.isValid())
689 Diag(ExportLoc, diag::warn_template_export_unsupported);
691 return TemplateParameterList::Create(Context, TemplateLoc, LAngleLoc,
692 (NamedDecl**)Params, NumParams,
696 static void SetNestedNameSpecifier(TagDecl *T, const CXXScopeSpec &SS) {
698 T->setQualifierInfo(static_cast<NestedNameSpecifier*>(SS.getScopeRep()),
703 Sema::CheckClassTemplate(Scope *S, unsigned TagSpec, TagUseKind TUK,
704 SourceLocation KWLoc, CXXScopeSpec &SS,
705 IdentifierInfo *Name, SourceLocation NameLoc,
707 TemplateParameterList *TemplateParams,
708 AccessSpecifier AS) {
709 assert(TemplateParams && TemplateParams->size() > 0 &&
710 "No template parameters");
711 assert(TUK != TUK_Reference && "Can only declare or define class templates");
712 bool Invalid = false;
714 // Check that we can declare a template here.
715 if (CheckTemplateDeclScope(S, TemplateParams))
718 TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec);
719 assert(Kind != TTK_Enum && "can't build template of enumerated type");
721 // There is no such thing as an unnamed class template.
723 Diag(KWLoc, diag::err_template_unnamed_class);
727 // Find any previous declaration with this name.
728 DeclContext *SemanticContext;
729 LookupResult Previous(*this, Name, NameLoc, LookupOrdinaryName,
731 if (SS.isNotEmpty() && !SS.isInvalid()) {
732 SemanticContext = computeDeclContext(SS, true);
733 if (!SemanticContext) {
734 // FIXME: Produce a reasonable diagnostic here
738 if (RequireCompleteDeclContext(SS, SemanticContext))
741 LookupQualifiedName(Previous, SemanticContext);
743 SemanticContext = CurContext;
744 LookupName(Previous, S);
747 if (Previous.isAmbiguous())
750 NamedDecl *PrevDecl = 0;
751 if (Previous.begin() != Previous.end())
752 PrevDecl = (*Previous.begin())->getUnderlyingDecl();
754 // If there is a previous declaration with the same name, check
755 // whether this is a valid redeclaration.
756 ClassTemplateDecl *PrevClassTemplate
757 = dyn_cast_or_null<ClassTemplateDecl>(PrevDecl);
759 // We may have found the injected-class-name of a class template,
760 // class template partial specialization, or class template specialization.
761 // In these cases, grab the template that is being defined or specialized.
762 if (!PrevClassTemplate && PrevDecl && isa<CXXRecordDecl>(PrevDecl) &&
763 cast<CXXRecordDecl>(PrevDecl)->isInjectedClassName()) {
764 PrevDecl = cast<CXXRecordDecl>(PrevDecl->getDeclContext());
766 = cast<CXXRecordDecl>(PrevDecl)->getDescribedClassTemplate();
767 if (!PrevClassTemplate && isa<ClassTemplateSpecializationDecl>(PrevDecl)) {
769 = cast<ClassTemplateSpecializationDecl>(PrevDecl)
770 ->getSpecializedTemplate();
774 if (TUK == TUK_Friend) {
775 // C++ [namespace.memdef]p3:
776 // [...] When looking for a prior declaration of a class or a function
777 // declared as a friend, and when the name of the friend class or
778 // function is neither a qualified name nor a template-id, scopes outside
779 // the innermost enclosing namespace scope are not considered.
781 DeclContext *OutermostContext = CurContext;
782 while (!OutermostContext->isFileContext())
783 OutermostContext = OutermostContext->getLookupParent();
786 (OutermostContext->Equals(PrevDecl->getDeclContext()) ||
787 OutermostContext->Encloses(PrevDecl->getDeclContext()))) {
788 SemanticContext = PrevDecl->getDeclContext();
790 // Declarations in outer scopes don't matter. However, the outermost
791 // context we computed is the semantic context for our new
793 PrevDecl = PrevClassTemplate = 0;
794 SemanticContext = OutermostContext;
798 if (CurContext->isDependentContext()) {
799 // If this is a dependent context, we don't want to link the friend
800 // class template to the template in scope, because that would perform
801 // checking of the template parameter lists that can't be performed
802 // until the outer context is instantiated.
803 PrevDecl = PrevClassTemplate = 0;
805 } else if (PrevDecl && !isDeclInScope(PrevDecl, SemanticContext, S))
806 PrevDecl = PrevClassTemplate = 0;
808 if (PrevClassTemplate) {
809 // Ensure that the template parameter lists are compatible.
810 if (!TemplateParameterListsAreEqual(TemplateParams,
811 PrevClassTemplate->getTemplateParameters(),
816 // C++ [temp.class]p4:
817 // In a redeclaration, partial specialization, explicit
818 // specialization or explicit instantiation of a class template,
819 // the class-key shall agree in kind with the original class
820 // template declaration (7.1.5.3).
821 RecordDecl *PrevRecordDecl = PrevClassTemplate->getTemplatedDecl();
822 if (!isAcceptableTagRedeclaration(PrevRecordDecl, Kind, KWLoc, *Name)) {
823 Diag(KWLoc, diag::err_use_with_wrong_tag)
825 << FixItHint::CreateReplacement(KWLoc, PrevRecordDecl->getKindName());
826 Diag(PrevRecordDecl->getLocation(), diag::note_previous_use);
827 Kind = PrevRecordDecl->getTagKind();
830 // Check for redefinition of this class template.
831 if (TUK == TUK_Definition) {
832 if (TagDecl *Def = PrevRecordDecl->getDefinition()) {
833 Diag(NameLoc, diag::err_redefinition) << Name;
834 Diag(Def->getLocation(), diag::note_previous_definition);
835 // FIXME: Would it make sense to try to "forget" the previous
836 // definition, as part of error recovery?
840 } else if (PrevDecl && PrevDecl->isTemplateParameter()) {
841 // Maybe we will complain about the shadowed template parameter.
842 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl);
843 // Just pretend that we didn't see the previous declaration.
845 } else if (PrevDecl) {
847 // A class template shall not have the same name as any other
848 // template, class, function, object, enumeration, enumerator,
849 // namespace, or type in the same scope (3.3), except as specified
851 Diag(NameLoc, diag::err_redefinition_different_kind) << Name;
852 Diag(PrevDecl->getLocation(), diag::note_previous_definition);
856 // Check the template parameter list of this declaration, possibly
857 // merging in the template parameter list from the previous class
858 // template declaration.
859 if (CheckTemplateParameterList(TemplateParams,
860 PrevClassTemplate? PrevClassTemplate->getTemplateParameters() : 0,
865 // If the name of the template was qualified, we must be defining the
866 // template out-of-line.
867 if (!SS.isInvalid() && !Invalid && !PrevClassTemplate &&
868 !(TUK == TUK_Friend && CurContext->isDependentContext()))
869 Diag(NameLoc, diag::err_member_def_does_not_match)
870 << Name << SemanticContext << SS.getRange();
873 CXXRecordDecl *NewClass =
874 CXXRecordDecl::Create(Context, Kind, SemanticContext, NameLoc, Name, KWLoc,
876 PrevClassTemplate->getTemplatedDecl() : 0,
877 /*DelayTypeCreation=*/true);
878 SetNestedNameSpecifier(NewClass, SS);
880 ClassTemplateDecl *NewTemplate
881 = ClassTemplateDecl::Create(Context, SemanticContext, NameLoc,
882 DeclarationName(Name), TemplateParams,
883 NewClass, PrevClassTemplate);
884 NewClass->setDescribedClassTemplate(NewTemplate);
886 // Build the type for the class template declaration now.
887 QualType T = NewTemplate->getInjectedClassNameSpecialization();
888 T = Context.getInjectedClassNameType(NewClass, T);
889 assert(T->isDependentType() && "Class template type is not dependent?");
892 // If we are providing an explicit specialization of a member that is a
893 // class template, make a note of that.
894 if (PrevClassTemplate &&
895 PrevClassTemplate->getInstantiatedFromMemberTemplate())
896 PrevClassTemplate->setMemberSpecialization();
898 // Set the access specifier.
899 if (!Invalid && TUK != TUK_Friend)
900 SetMemberAccessSpecifier(NewTemplate, PrevClassTemplate, AS);
902 // Set the lexical context of these templates
903 NewClass->setLexicalDeclContext(CurContext);
904 NewTemplate->setLexicalDeclContext(CurContext);
906 if (TUK == TUK_Definition)
907 NewClass->startDefinition();
910 ProcessDeclAttributeList(S, NewClass, Attr);
912 if (TUK != TUK_Friend)
913 PushOnScopeChains(NewTemplate, S);
915 if (PrevClassTemplate && PrevClassTemplate->getAccess() != AS_none) {
916 NewTemplate->setAccess(PrevClassTemplate->getAccess());
917 NewClass->setAccess(PrevClassTemplate->getAccess());
920 NewTemplate->setObjectOfFriendDecl(/* PreviouslyDeclared = */
921 PrevClassTemplate != NULL);
923 // Friend templates are visible in fairly strange ways.
924 if (!CurContext->isDependentContext()) {
925 DeclContext *DC = SemanticContext->getLookupContext();
926 DC->makeDeclVisibleInContext(NewTemplate, /* Recoverable = */ false);
927 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC))
928 PushOnScopeChains(NewTemplate, EnclosingScope,
929 /* AddToContext = */ false);
932 FriendDecl *Friend = FriendDecl::Create(Context, CurContext,
933 NewClass->getLocation(),
935 /*FIXME:*/NewClass->getLocation());
936 Friend->setAccess(AS_public);
937 CurContext->addDecl(Friend);
941 NewTemplate->setInvalidDecl();
942 NewClass->setInvalidDecl();
944 return DeclPtrTy::make(NewTemplate);
947 /// \brief Diagnose the presence of a default template argument on a
948 /// template parameter, which is ill-formed in certain contexts.
950 /// \returns true if the default template argument should be dropped.
951 static bool DiagnoseDefaultTemplateArgument(Sema &S,
952 Sema::TemplateParamListContext TPC,
953 SourceLocation ParamLoc,
954 SourceRange DefArgRange) {
956 case Sema::TPC_ClassTemplate:
959 case Sema::TPC_FunctionTemplate:
960 // C++ [temp.param]p9:
961 // A default template-argument shall not be specified in a
962 // function template declaration or a function template
964 // (This sentence is not in C++0x, per DR226).
965 if (!S.getLangOptions().CPlusPlus0x)
967 diag::err_template_parameter_default_in_function_template)
971 case Sema::TPC_ClassTemplateMember:
972 // C++0x [temp.param]p9:
973 // A default template-argument shall not be specified in the
974 // template-parameter-lists of the definition of a member of a
975 // class template that appears outside of the member's class.
976 S.Diag(ParamLoc, diag::err_template_parameter_default_template_member)
980 case Sema::TPC_FriendFunctionTemplate:
981 // C++ [temp.param]p9:
982 // A default template-argument shall not be specified in a
983 // friend template declaration.
984 S.Diag(ParamLoc, diag::err_template_parameter_default_friend_template)
988 // FIXME: C++0x [temp.param]p9 allows default template-arguments
989 // for friend function templates if there is only a single
990 // declaration (and it is a definition). Strange!
996 /// \brief Checks the validity of a template parameter list, possibly
997 /// considering the template parameter list from a previous
1000 /// If an "old" template parameter list is provided, it must be
1001 /// equivalent (per TemplateParameterListsAreEqual) to the "new"
1002 /// template parameter list.
1004 /// \param NewParams Template parameter list for a new template
1005 /// declaration. This template parameter list will be updated with any
1006 /// default arguments that are carried through from the previous
1007 /// template parameter list.
1009 /// \param OldParams If provided, template parameter list from a
1010 /// previous declaration of the same template. Default template
1011 /// arguments will be merged from the old template parameter list to
1012 /// the new template parameter list.
1014 /// \param TPC Describes the context in which we are checking the given
1015 /// template parameter list.
1017 /// \returns true if an error occurred, false otherwise.
1018 bool Sema::CheckTemplateParameterList(TemplateParameterList *NewParams,
1019 TemplateParameterList *OldParams,
1020 TemplateParamListContext TPC) {
1021 bool Invalid = false;
1023 // C++ [temp.param]p10:
1024 // The set of default template-arguments available for use with a
1025 // template declaration or definition is obtained by merging the
1026 // default arguments from the definition (if in scope) and all
1027 // declarations in scope in the same way default function
1028 // arguments are (8.3.6).
1029 bool SawDefaultArgument = false;
1030 SourceLocation PreviousDefaultArgLoc;
1032 bool SawParameterPack = false;
1033 SourceLocation ParameterPackLoc;
1035 // Dummy initialization to avoid warnings.
1036 TemplateParameterList::iterator OldParam = NewParams->end();
1038 OldParam = OldParams->begin();
1040 for (TemplateParameterList::iterator NewParam = NewParams->begin(),
1041 NewParamEnd = NewParams->end();
1042 NewParam != NewParamEnd; ++NewParam) {
1043 // Variables used to diagnose redundant default arguments
1044 bool RedundantDefaultArg = false;
1045 SourceLocation OldDefaultLoc;
1046 SourceLocation NewDefaultLoc;
1048 // Variables used to diagnose missing default arguments
1049 bool MissingDefaultArg = false;
1051 // C++0x [temp.param]p11:
1052 // If a template parameter of a class template is a template parameter pack,
1053 // it must be the last template parameter.
1054 if (SawParameterPack) {
1055 Diag(ParameterPackLoc,
1056 diag::err_template_param_pack_must_be_last_template_parameter);
1060 if (TemplateTypeParmDecl *NewTypeParm
1061 = dyn_cast<TemplateTypeParmDecl>(*NewParam)) {
1062 // Check the presence of a default argument here.
1063 if (NewTypeParm->hasDefaultArgument() &&
1064 DiagnoseDefaultTemplateArgument(*this, TPC,
1065 NewTypeParm->getLocation(),
1066 NewTypeParm->getDefaultArgumentInfo()->getTypeLoc()
1068 NewTypeParm->removeDefaultArgument();
1070 // Merge default arguments for template type parameters.
1071 TemplateTypeParmDecl *OldTypeParm
1072 = OldParams? cast<TemplateTypeParmDecl>(*OldParam) : 0;
1074 if (NewTypeParm->isParameterPack()) {
1075 assert(!NewTypeParm->hasDefaultArgument() &&
1076 "Parameter packs can't have a default argument!");
1077 SawParameterPack = true;
1078 ParameterPackLoc = NewTypeParm->getLocation();
1079 } else if (OldTypeParm && OldTypeParm->hasDefaultArgument() &&
1080 NewTypeParm->hasDefaultArgument()) {
1081 OldDefaultLoc = OldTypeParm->getDefaultArgumentLoc();
1082 NewDefaultLoc = NewTypeParm->getDefaultArgumentLoc();
1083 SawDefaultArgument = true;
1084 RedundantDefaultArg = true;
1085 PreviousDefaultArgLoc = NewDefaultLoc;
1086 } else if (OldTypeParm && OldTypeParm->hasDefaultArgument()) {
1087 // Merge the default argument from the old declaration to the
1089 SawDefaultArgument = true;
1090 NewTypeParm->setDefaultArgument(OldTypeParm->getDefaultArgumentInfo(),
1092 PreviousDefaultArgLoc = OldTypeParm->getDefaultArgumentLoc();
1093 } else if (NewTypeParm->hasDefaultArgument()) {
1094 SawDefaultArgument = true;
1095 PreviousDefaultArgLoc = NewTypeParm->getDefaultArgumentLoc();
1096 } else if (SawDefaultArgument)
1097 MissingDefaultArg = true;
1098 } else if (NonTypeTemplateParmDecl *NewNonTypeParm
1099 = dyn_cast<NonTypeTemplateParmDecl>(*NewParam)) {
1100 // Check the presence of a default argument here.
1101 if (NewNonTypeParm->hasDefaultArgument() &&
1102 DiagnoseDefaultTemplateArgument(*this, TPC,
1103 NewNonTypeParm->getLocation(),
1104 NewNonTypeParm->getDefaultArgument()->getSourceRange())) {
1105 NewNonTypeParm->getDefaultArgument()->Destroy(Context);
1106 NewNonTypeParm->removeDefaultArgument();
1109 // Merge default arguments for non-type template parameters
1110 NonTypeTemplateParmDecl *OldNonTypeParm
1111 = OldParams? cast<NonTypeTemplateParmDecl>(*OldParam) : 0;
1112 if (OldNonTypeParm && OldNonTypeParm->hasDefaultArgument() &&
1113 NewNonTypeParm->hasDefaultArgument()) {
1114 OldDefaultLoc = OldNonTypeParm->getDefaultArgumentLoc();
1115 NewDefaultLoc = NewNonTypeParm->getDefaultArgumentLoc();
1116 SawDefaultArgument = true;
1117 RedundantDefaultArg = true;
1118 PreviousDefaultArgLoc = NewDefaultLoc;
1119 } else if (OldNonTypeParm && OldNonTypeParm->hasDefaultArgument()) {
1120 // Merge the default argument from the old declaration to the
1122 SawDefaultArgument = true;
1123 // FIXME: We need to create a new kind of "default argument"
1124 // expression that points to a previous template template
1126 NewNonTypeParm->setDefaultArgument(
1127 OldNonTypeParm->getDefaultArgument(),
1128 /*Inherited=*/ true);
1129 PreviousDefaultArgLoc = OldNonTypeParm->getDefaultArgumentLoc();
1130 } else if (NewNonTypeParm->hasDefaultArgument()) {
1131 SawDefaultArgument = true;
1132 PreviousDefaultArgLoc = NewNonTypeParm->getDefaultArgumentLoc();
1133 } else if (SawDefaultArgument)
1134 MissingDefaultArg = true;
1136 // Check the presence of a default argument here.
1137 TemplateTemplateParmDecl *NewTemplateParm
1138 = cast<TemplateTemplateParmDecl>(*NewParam);
1139 if (NewTemplateParm->hasDefaultArgument() &&
1140 DiagnoseDefaultTemplateArgument(*this, TPC,
1141 NewTemplateParm->getLocation(),
1142 NewTemplateParm->getDefaultArgument().getSourceRange()))
1143 NewTemplateParm->removeDefaultArgument();
1145 // Merge default arguments for template template parameters
1146 TemplateTemplateParmDecl *OldTemplateParm
1147 = OldParams? cast<TemplateTemplateParmDecl>(*OldParam) : 0;
1148 if (OldTemplateParm && OldTemplateParm->hasDefaultArgument() &&
1149 NewTemplateParm->hasDefaultArgument()) {
1150 OldDefaultLoc = OldTemplateParm->getDefaultArgument().getLocation();
1151 NewDefaultLoc = NewTemplateParm->getDefaultArgument().getLocation();
1152 SawDefaultArgument = true;
1153 RedundantDefaultArg = true;
1154 PreviousDefaultArgLoc = NewDefaultLoc;
1155 } else if (OldTemplateParm && OldTemplateParm->hasDefaultArgument()) {
1156 // Merge the default argument from the old declaration to the
1158 SawDefaultArgument = true;
1159 // FIXME: We need to create a new kind of "default argument" expression
1160 // that points to a previous template template parameter.
1161 NewTemplateParm->setDefaultArgument(
1162 OldTemplateParm->getDefaultArgument(),
1163 /*Inherited=*/ true);
1164 PreviousDefaultArgLoc
1165 = OldTemplateParm->getDefaultArgument().getLocation();
1166 } else if (NewTemplateParm->hasDefaultArgument()) {
1167 SawDefaultArgument = true;
1168 PreviousDefaultArgLoc
1169 = NewTemplateParm->getDefaultArgument().getLocation();
1170 } else if (SawDefaultArgument)
1171 MissingDefaultArg = true;
1174 if (RedundantDefaultArg) {
1175 // C++ [temp.param]p12:
1176 // A template-parameter shall not be given default arguments
1177 // by two different declarations in the same scope.
1178 Diag(NewDefaultLoc, diag::err_template_param_default_arg_redefinition);
1179 Diag(OldDefaultLoc, diag::note_template_param_prev_default_arg);
1181 } else if (MissingDefaultArg) {
1182 // C++ [temp.param]p11:
1183 // If a template-parameter has a default template-argument,
1184 // all subsequent template-parameters shall have a default
1185 // template-argument supplied.
1186 Diag((*NewParam)->getLocation(),
1187 diag::err_template_param_default_arg_missing);
1188 Diag(PreviousDefaultArgLoc, diag::note_template_param_prev_default_arg);
1192 // If we have an old template parameter list that we're merging
1193 // in, move on to the next parameter.
1201 /// \brief Match the given template parameter lists to the given scope
1202 /// specifier, returning the template parameter list that applies to the
1205 /// \param DeclStartLoc the start of the declaration that has a scope
1206 /// specifier or a template parameter list.
1208 /// \param SS the scope specifier that will be matched to the given template
1209 /// parameter lists. This scope specifier precedes a qualified name that is
1212 /// \param ParamLists the template parameter lists, from the outermost to the
1213 /// innermost template parameter lists.
1215 /// \param NumParamLists the number of template parameter lists in ParamLists.
1217 /// \param IsFriend Whether to apply the slightly different rules for
1218 /// matching template parameters to scope specifiers in friend
1221 /// \param IsExplicitSpecialization will be set true if the entity being
1222 /// declared is an explicit specialization, false otherwise.
1224 /// \returns the template parameter list, if any, that corresponds to the
1225 /// name that is preceded by the scope specifier @p SS. This template
1226 /// parameter list may be have template parameters (if we're declaring a
1227 /// template) or may have no template parameters (if we're declaring a
1228 /// template specialization), or may be NULL (if we were's declaring isn't
1229 /// itself a template).
1230 TemplateParameterList *
1231 Sema::MatchTemplateParametersToScopeSpecifier(SourceLocation DeclStartLoc,
1232 const CXXScopeSpec &SS,
1233 TemplateParameterList **ParamLists,
1234 unsigned NumParamLists,
1236 bool &IsExplicitSpecialization,
1238 IsExplicitSpecialization = false;
1240 // Find the template-ids that occur within the nested-name-specifier. These
1241 // template-ids will match up with the template parameter lists.
1242 llvm::SmallVector<const TemplateSpecializationType *, 4>
1243 TemplateIdsInSpecifier;
1244 llvm::SmallVector<ClassTemplateSpecializationDecl *, 4>
1245 ExplicitSpecializationsInSpecifier;
1246 for (NestedNameSpecifier *NNS = (NestedNameSpecifier *)SS.getScopeRep();
1247 NNS; NNS = NNS->getPrefix()) {
1248 const Type *T = NNS->getAsType();
1251 // C++0x [temp.expl.spec]p17:
1252 // A member or a member template may be nested within many
1253 // enclosing class templates. In an explicit specialization for
1254 // such a member, the member declaration shall be preceded by a
1255 // template<> for each enclosing class template that is
1256 // explicitly specialized.
1258 // Following the existing practice of GNU and EDG, we allow a typedef of a
1259 // template specialization type.
1260 if (const TypedefType *TT = dyn_cast<TypedefType>(T))
1261 T = TT->LookThroughTypedefs().getTypePtr();
1263 if (const TemplateSpecializationType *SpecType
1264 = dyn_cast<TemplateSpecializationType>(T)) {
1265 TemplateDecl *Template = SpecType->getTemplateName().getAsTemplateDecl();
1267 continue; // FIXME: should this be an error? probably...
1269 if (const RecordType *Record = SpecType->getAs<RecordType>()) {
1270 ClassTemplateSpecializationDecl *SpecDecl
1271 = cast<ClassTemplateSpecializationDecl>(Record->getDecl());
1272 // If the nested name specifier refers to an explicit specialization,
1273 // we don't need a template<> header.
1274 if (SpecDecl->getSpecializationKind() == TSK_ExplicitSpecialization) {
1275 ExplicitSpecializationsInSpecifier.push_back(SpecDecl);
1280 TemplateIdsInSpecifier.push_back(SpecType);
1284 // Reverse the list of template-ids in the scope specifier, so that we can
1285 // more easily match up the template-ids and the template parameter lists.
1286 std::reverse(TemplateIdsInSpecifier.begin(), TemplateIdsInSpecifier.end());
1288 SourceLocation FirstTemplateLoc = DeclStartLoc;
1290 FirstTemplateLoc = ParamLists[0]->getTemplateLoc();
1292 // Match the template-ids found in the specifier to the template parameter
1295 for (unsigned NumTemplateIds = TemplateIdsInSpecifier.size();
1296 Idx != NumTemplateIds; ++Idx) {
1297 QualType TemplateId = QualType(TemplateIdsInSpecifier[Idx], 0);
1298 bool DependentTemplateId = TemplateId->isDependentType();
1299 if (Idx >= NumParamLists) {
1300 // We have a template-id without a corresponding template parameter
1303 // ...which is fine if this is a friend declaration.
1305 IsExplicitSpecialization = true;
1309 if (DependentTemplateId) {
1310 // FIXME: the location information here isn't great.
1311 Diag(SS.getRange().getBegin(),
1312 diag::err_template_spec_needs_template_parameters)
1317 Diag(SS.getRange().getBegin(), diag::err_template_spec_needs_header)
1319 << FixItHint::CreateInsertion(FirstTemplateLoc, "template<> ");
1320 IsExplicitSpecialization = true;
1325 // Check the template parameter list against its corresponding template-id.
1326 if (DependentTemplateId) {
1327 TemplateParameterList *ExpectedTemplateParams = 0;
1329 // Are there cases in (e.g.) friends where this won't match?
1330 if (const InjectedClassNameType *Injected
1331 = TemplateId->getAs<InjectedClassNameType>()) {
1332 CXXRecordDecl *Record = Injected->getDecl();
1333 if (ClassTemplatePartialSpecializationDecl *Partial =
1334 dyn_cast<ClassTemplatePartialSpecializationDecl>(Record))
1335 ExpectedTemplateParams = Partial->getTemplateParameters();
1337 ExpectedTemplateParams = Record->getDescribedClassTemplate()
1338 ->getTemplateParameters();
1341 if (ExpectedTemplateParams)
1342 TemplateParameterListsAreEqual(ParamLists[Idx],
1343 ExpectedTemplateParams,
1344 true, TPL_TemplateMatch);
1346 CheckTemplateParameterList(ParamLists[Idx], 0, TPC_ClassTemplateMember);
1347 } else if (ParamLists[Idx]->size() > 0)
1348 Diag(ParamLists[Idx]->getTemplateLoc(),
1349 diag::err_template_param_list_matches_nontemplate)
1351 << ParamLists[Idx]->getSourceRange();
1353 IsExplicitSpecialization = true;
1356 // If there were at least as many template-ids as there were template
1357 // parameter lists, then there are no template parameter lists remaining for
1358 // the declaration itself.
1359 if (Idx >= NumParamLists)
1362 // If there were too many template parameter lists, complain about that now.
1363 if (Idx != NumParamLists - 1) {
1364 while (Idx < NumParamLists - 1) {
1365 bool isExplicitSpecHeader = ParamLists[Idx]->size() == 0;
1366 Diag(ParamLists[Idx]->getTemplateLoc(),
1367 isExplicitSpecHeader? diag::warn_template_spec_extra_headers
1368 : diag::err_template_spec_extra_headers)
1369 << SourceRange(ParamLists[Idx]->getTemplateLoc(),
1370 ParamLists[Idx]->getRAngleLoc());
1372 if (isExplicitSpecHeader && !ExplicitSpecializationsInSpecifier.empty()) {
1373 Diag(ExplicitSpecializationsInSpecifier.back()->getLocation(),
1374 diag::note_explicit_template_spec_does_not_need_header)
1375 << ExplicitSpecializationsInSpecifier.back();
1376 ExplicitSpecializationsInSpecifier.pop_back();
1379 // We have a template parameter list with no corresponding scope, which
1380 // means that the resulting template declaration can't be instantiated
1381 // properly (we'll end up with dependent nodes when we shouldn't).
1382 if (!isExplicitSpecHeader)
1389 // Return the last template parameter list, which corresponds to the
1390 // entity being declared.
1391 return ParamLists[NumParamLists - 1];
1394 QualType Sema::CheckTemplateIdType(TemplateName Name,
1395 SourceLocation TemplateLoc,
1396 const TemplateArgumentListInfo &TemplateArgs) {
1397 TemplateDecl *Template = Name.getAsTemplateDecl();
1399 // The template name does not resolve to a template, so we just
1400 // build a dependent template-id type.
1401 return Context.getTemplateSpecializationType(Name, TemplateArgs);
1404 // Check that the template argument list is well-formed for this
1406 TemplateArgumentListBuilder Converted(Template->getTemplateParameters(),
1407 TemplateArgs.size());
1408 if (CheckTemplateArgumentList(Template, TemplateLoc, TemplateArgs,
1412 assert((Converted.structuredSize() ==
1413 Template->getTemplateParameters()->size()) &&
1414 "Converted template argument list is too short!");
1418 if (Name.isDependent() ||
1419 TemplateSpecializationType::anyDependentTemplateArguments(
1421 // This class template specialization is a dependent
1422 // type. Therefore, its canonical type is another class template
1423 // specialization type that contains all of the converted
1424 // arguments in canonical form. This ensures that, e.g., A<T> and
1425 // A<T, T> have identical types when A is declared as:
1427 // template<typename T, typename U = T> struct A;
1428 TemplateName CanonName = Context.getCanonicalTemplateName(Name);
1429 CanonType = Context.getTemplateSpecializationType(CanonName,
1430 Converted.getFlatArguments(),
1431 Converted.flatSize());
1433 // FIXME: CanonType is not actually the canonical type, and unfortunately
1434 // it is a TemplateSpecializationType that we will never use again.
1435 // In the future, we need to teach getTemplateSpecializationType to only
1436 // build the canonical type and return that to us.
1437 CanonType = Context.getCanonicalType(CanonType);
1439 // This might work out to be a current instantiation, in which
1440 // case the canonical type needs to be the InjectedClassNameType.
1442 // TODO: in theory this could be a simple hashtable lookup; most
1443 // changes to CurContext don't change the set of current
1445 if (isa<ClassTemplateDecl>(Template)) {
1446 for (DeclContext *Ctx = CurContext; Ctx; Ctx = Ctx->getLookupParent()) {
1447 // If we get out to a namespace, we're done.
1448 if (Ctx->isFileContext()) break;
1450 // If this isn't a record, keep looking.
1451 CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Ctx);
1452 if (!Record) continue;
1454 // Look for one of the two cases with InjectedClassNameTypes
1455 // and check whether it's the same template.
1456 if (!isa<ClassTemplatePartialSpecializationDecl>(Record) &&
1457 !Record->getDescribedClassTemplate())
1460 // Fetch the injected class name type and check whether its
1461 // injected type is equal to the type we just built.
1462 QualType ICNT = Context.getTypeDeclType(Record);
1463 QualType Injected = cast<InjectedClassNameType>(ICNT)
1464 ->getInjectedSpecializationType();
1466 if (CanonType != Injected->getCanonicalTypeInternal())
1469 // If so, the canonical type of this TST is the injected
1470 // class name type of the record we just found.
1471 assert(ICNT.isCanonical());
1476 } else if (ClassTemplateDecl *ClassTemplate
1477 = dyn_cast<ClassTemplateDecl>(Template)) {
1478 // Find the class template specialization declaration that
1479 // corresponds to these arguments.
1480 llvm::FoldingSetNodeID ID;
1481 ClassTemplateSpecializationDecl::Profile(ID,
1482 Converted.getFlatArguments(),
1483 Converted.flatSize(),
1485 void *InsertPos = 0;
1486 ClassTemplateSpecializationDecl *Decl
1487 = ClassTemplate->getSpecializations().FindNodeOrInsertPos(ID, InsertPos);
1489 // This is the first time we have referenced this class template
1490 // specialization. Create the canonical declaration and add it to
1491 // the set of specializations.
1492 Decl = ClassTemplateSpecializationDecl::Create(Context,
1493 ClassTemplate->getTemplatedDecl()->getTagKind(),
1494 ClassTemplate->getDeclContext(),
1495 ClassTemplate->getLocation(),
1498 ClassTemplate->getSpecializations().InsertNode(Decl, InsertPos);
1499 Decl->setLexicalDeclContext(CurContext);
1502 CanonType = Context.getTypeDeclType(Decl);
1503 assert(isa<RecordType>(CanonType) &&
1504 "type of non-dependent specialization is not a RecordType");
1507 // Build the fully-sugared type for this class template
1508 // specialization, which refers back to the class template
1509 // specialization we created or found.
1510 return Context.getTemplateSpecializationType(Name, TemplateArgs, CanonType);
1514 Sema::ActOnTemplateIdType(TemplateTy TemplateD, SourceLocation TemplateLoc,
1515 SourceLocation LAngleLoc,
1516 ASTTemplateArgsPtr TemplateArgsIn,
1517 SourceLocation RAngleLoc) {
1518 TemplateName Template = TemplateD.getAsVal<TemplateName>();
1520 // Translate the parser's template argument list in our AST format.
1521 TemplateArgumentListInfo TemplateArgs(LAngleLoc, RAngleLoc);
1522 translateTemplateArguments(TemplateArgsIn, TemplateArgs);
1524 QualType Result = CheckTemplateIdType(Template, TemplateLoc, TemplateArgs);
1525 TemplateArgsIn.release();
1527 if (Result.isNull())
1530 TypeSourceInfo *DI = Context.CreateTypeSourceInfo(Result);
1531 TemplateSpecializationTypeLoc TL
1532 = cast<TemplateSpecializationTypeLoc>(DI->getTypeLoc());
1533 TL.setTemplateNameLoc(TemplateLoc);
1534 TL.setLAngleLoc(LAngleLoc);
1535 TL.setRAngleLoc(RAngleLoc);
1536 for (unsigned i = 0, e = TL.getNumArgs(); i != e; ++i)
1537 TL.setArgLocInfo(i, TemplateArgs[i].getLocInfo());
1539 return CreateLocInfoType(Result, DI).getAsOpaquePtr();
1542 Sema::TypeResult Sema::ActOnTagTemplateIdType(TypeResult TypeResult,
1544 DeclSpec::TST TagSpec,
1545 SourceLocation TagLoc) {
1546 if (TypeResult.isInvalid())
1547 return Sema::TypeResult();
1549 // FIXME: preserve source info, ideally without copying the DI.
1551 QualType Type = GetTypeFromParser(TypeResult.get(), &DI);
1553 // Verify the tag specifier.
1554 TagTypeKind TagKind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec);
1556 if (const RecordType *RT = Type->getAs<RecordType>()) {
1557 RecordDecl *D = RT->getDecl();
1559 IdentifierInfo *Id = D->getIdentifier();
1560 assert(Id && "templated class must have an identifier");
1562 if (!isAcceptableTagRedeclaration(D, TagKind, TagLoc, *Id)) {
1563 Diag(TagLoc, diag::err_use_with_wrong_tag)
1565 << FixItHint::CreateReplacement(SourceRange(TagLoc), D->getKindName());
1566 Diag(D->getLocation(), diag::note_previous_use);
1570 ElaboratedTypeKeyword Keyword
1571 = TypeWithKeyword::getKeywordForTagTypeKind(TagKind);
1572 QualType ElabType = Context.getElaboratedType(Keyword, /*NNS=*/0, Type);
1574 return ElabType.getAsOpaquePtr();
1577 Sema::OwningExprResult Sema::BuildTemplateIdExpr(const CXXScopeSpec &SS,
1580 const TemplateArgumentListInfo &TemplateArgs) {
1581 // FIXME: Can we do any checking at this point? I guess we could check the
1582 // template arguments that we have against the template name, if the template
1583 // name refers to a single template. That's not a terribly common case,
1586 // These should be filtered out by our callers.
1587 assert(!R.empty() && "empty lookup results when building templateid");
1588 assert(!R.isAmbiguous() && "ambiguous lookup when building templateid");
1590 NestedNameSpecifier *Qualifier = 0;
1591 SourceRange QualifierRange;
1593 Qualifier = static_cast<NestedNameSpecifier*>(SS.getScopeRep());
1594 QualifierRange = SS.getRange();
1597 // We don't want lookup warnings at this point.
1598 R.suppressDiagnostics();
1601 = UnresolvedLookupExpr::ComputeDependence(R.begin(), R.end(),
1603 UnresolvedLookupExpr *ULE
1604 = UnresolvedLookupExpr::Create(Context, Dependent, R.getNamingClass(),
1605 Qualifier, QualifierRange,
1606 R.getLookupName(), R.getNameLoc(),
1607 RequiresADL, TemplateArgs,
1608 R.begin(), R.end());
1613 // We actually only call this from template instantiation.
1614 Sema::OwningExprResult
1615 Sema::BuildQualifiedTemplateIdExpr(CXXScopeSpec &SS,
1616 DeclarationName Name,
1617 SourceLocation NameLoc,
1618 const TemplateArgumentListInfo &TemplateArgs) {
1620 if (!(DC = computeDeclContext(SS, false)) ||
1621 DC->isDependentContext() ||
1622 RequireCompleteDeclContext(SS, DC))
1623 return BuildDependentDeclRefExpr(SS, Name, NameLoc, &TemplateArgs);
1625 bool MemberOfUnknownSpecialization;
1626 LookupResult R(*this, Name, NameLoc, LookupOrdinaryName);
1627 LookupTemplateName(R, (Scope*) 0, SS, QualType(), /*Entering*/ false,
1628 MemberOfUnknownSpecialization);
1630 if (R.isAmbiguous())
1634 Diag(NameLoc, diag::err_template_kw_refers_to_non_template)
1635 << Name << SS.getRange();
1639 if (ClassTemplateDecl *Temp = R.getAsSingle<ClassTemplateDecl>()) {
1640 Diag(NameLoc, diag::err_template_kw_refers_to_class_template)
1641 << (NestedNameSpecifier*) SS.getScopeRep() << Name << SS.getRange();
1642 Diag(Temp->getLocation(), diag::note_referenced_class_template);
1646 return BuildTemplateIdExpr(SS, R, /* ADL */ false, TemplateArgs);
1649 /// \brief Form a dependent template name.
1651 /// This action forms a dependent template name given the template
1652 /// name and its (presumably dependent) scope specifier. For
1653 /// example, given "MetaFun::template apply", the scope specifier \p
1654 /// SS will be "MetaFun::", \p TemplateKWLoc contains the location
1655 /// of the "template" keyword, and "apply" is the \p Name.
1656 TemplateNameKind Sema::ActOnDependentTemplateName(Scope *S,
1657 SourceLocation TemplateKWLoc,
1659 UnqualifiedId &Name,
1661 bool EnteringContext,
1662 TemplateTy &Result) {
1663 if (TemplateKWLoc.isValid() && S && !S->getTemplateParamParent() &&
1664 !getLangOptions().CPlusPlus0x)
1665 Diag(TemplateKWLoc, diag::ext_template_outside_of_template)
1666 << FixItHint::CreateRemoval(TemplateKWLoc);
1668 DeclContext *LookupCtx = 0;
1670 LookupCtx = computeDeclContext(SS, EnteringContext);
1671 if (!LookupCtx && ObjectType)
1672 LookupCtx = computeDeclContext(QualType::getFromOpaquePtr(ObjectType));
1674 // C++0x [temp.names]p5:
1675 // If a name prefixed by the keyword template is not the name of
1676 // a template, the program is ill-formed. [Note: the keyword
1677 // template may not be applied to non-template members of class
1678 // templates. -end note ] [ Note: as is the case with the
1679 // typename prefix, the template prefix is allowed in cases
1680 // where it is not strictly necessary; i.e., when the
1681 // nested-name-specifier or the expression on the left of the ->
1682 // or . is not dependent on a template-parameter, or the use
1683 // does not appear in the scope of a template. -end note]
1685 // Note: C++03 was more strict here, because it banned the use of
1686 // the "template" keyword prior to a template-name that was not a
1687 // dependent name. C++ DR468 relaxed this requirement (the
1688 // "template" keyword is now permitted). We follow the C++0x
1689 // rules, even in C++03 mode with a warning, retroactively applying the DR.
1690 bool MemberOfUnknownSpecialization;
1691 TemplateNameKind TNK = isTemplateName(0, SS, Name, ObjectType,
1692 EnteringContext, Result,
1693 MemberOfUnknownSpecialization);
1694 if (TNK == TNK_Non_template && LookupCtx->isDependentContext() &&
1695 isa<CXXRecordDecl>(LookupCtx) &&
1696 cast<CXXRecordDecl>(LookupCtx)->hasAnyDependentBases()) {
1697 // This is a dependent template. Handle it below.
1698 } else if (TNK == TNK_Non_template) {
1699 Diag(Name.getSourceRange().getBegin(),
1700 diag::err_template_kw_refers_to_non_template)
1701 << GetNameFromUnqualifiedId(Name)
1702 << Name.getSourceRange()
1704 return TNK_Non_template;
1706 // We found something; return it.
1711 NestedNameSpecifier *Qualifier
1712 = static_cast<NestedNameSpecifier *>(SS.getScopeRep());
1714 switch (Name.getKind()) {
1715 case UnqualifiedId::IK_Identifier:
1716 Result = TemplateTy::make(Context.getDependentTemplateName(Qualifier,
1718 return TNK_Dependent_template_name;
1720 case UnqualifiedId::IK_OperatorFunctionId:
1721 Result = TemplateTy::make(Context.getDependentTemplateName(Qualifier,
1722 Name.OperatorFunctionId.Operator));
1723 return TNK_Dependent_template_name;
1725 case UnqualifiedId::IK_LiteralOperatorId:
1726 assert(false && "We don't support these; Parse shouldn't have allowed propagation");
1732 Diag(Name.getSourceRange().getBegin(),
1733 diag::err_template_kw_refers_to_non_template)
1734 << GetNameFromUnqualifiedId(Name)
1735 << Name.getSourceRange()
1737 return TNK_Non_template;
1740 bool Sema::CheckTemplateTypeArgument(TemplateTypeParmDecl *Param,
1741 const TemplateArgumentLoc &AL,
1742 TemplateArgumentListBuilder &Converted) {
1743 const TemplateArgument &Arg = AL.getArgument();
1745 // Check template type parameter.
1746 switch(Arg.getKind()) {
1747 case TemplateArgument::Type:
1748 // C++ [temp.arg.type]p1:
1749 // A template-argument for a template-parameter which is a
1750 // type shall be a type-id.
1752 case TemplateArgument::Template: {
1753 // We have a template type parameter but the template argument
1754 // is a template without any arguments.
1755 SourceRange SR = AL.getSourceRange();
1756 TemplateName Name = Arg.getAsTemplate();
1757 Diag(SR.getBegin(), diag::err_template_missing_args)
1759 if (TemplateDecl *Decl = Name.getAsTemplateDecl())
1760 Diag(Decl->getLocation(), diag::note_template_decl_here);
1765 // We have a template type parameter but the template argument
1767 SourceRange SR = AL.getSourceRange();
1768 Diag(SR.getBegin(), diag::err_template_arg_must_be_type) << SR;
1769 Diag(Param->getLocation(), diag::note_template_param_here);
1775 if (CheckTemplateArgument(Param, AL.getTypeSourceInfo()))
1778 // Add the converted template type argument.
1780 TemplateArgument(Context.getCanonicalType(Arg.getAsType())));
1784 /// \brief Substitute template arguments into the default template argument for
1785 /// the given template type parameter.
1787 /// \param SemaRef the semantic analysis object for which we are performing
1788 /// the substitution.
1790 /// \param Template the template that we are synthesizing template arguments
1793 /// \param TemplateLoc the location of the template name that started the
1794 /// template-id we are checking.
1796 /// \param RAngleLoc the location of the right angle bracket ('>') that
1797 /// terminates the template-id.
1799 /// \param Param the template template parameter whose default we are
1800 /// substituting into.
1802 /// \param Converted the list of template arguments provided for template
1803 /// parameters that precede \p Param in the template parameter list.
1805 /// \returns the substituted template argument, or NULL if an error occurred.
1806 static TypeSourceInfo *
1807 SubstDefaultTemplateArgument(Sema &SemaRef,
1808 TemplateDecl *Template,
1809 SourceLocation TemplateLoc,
1810 SourceLocation RAngleLoc,
1811 TemplateTypeParmDecl *Param,
1812 TemplateArgumentListBuilder &Converted) {
1813 TypeSourceInfo *ArgType = Param->getDefaultArgumentInfo();
1815 // If the argument type is dependent, instantiate it now based
1816 // on the previously-computed template arguments.
1817 if (ArgType->getType()->isDependentType()) {
1818 TemplateArgumentList TemplateArgs(SemaRef.Context, Converted,
1819 /*TakeArgs=*/false);
1821 MultiLevelTemplateArgumentList AllTemplateArgs
1822 = SemaRef.getTemplateInstantiationArgs(Template, &TemplateArgs);
1824 Sema::InstantiatingTemplate Inst(SemaRef, TemplateLoc,
1825 Template, Converted.getFlatArguments(),
1826 Converted.flatSize(),
1827 SourceRange(TemplateLoc, RAngleLoc));
1829 ArgType = SemaRef.SubstType(ArgType, AllTemplateArgs,
1830 Param->getDefaultArgumentLoc(),
1831 Param->getDeclName());
1837 /// \brief Substitute template arguments into the default template argument for
1838 /// the given non-type template parameter.
1840 /// \param SemaRef the semantic analysis object for which we are performing
1841 /// the substitution.
1843 /// \param Template the template that we are synthesizing template arguments
1846 /// \param TemplateLoc the location of the template name that started the
1847 /// template-id we are checking.
1849 /// \param RAngleLoc the location of the right angle bracket ('>') that
1850 /// terminates the template-id.
1852 /// \param Param the non-type template parameter whose default we are
1853 /// substituting into.
1855 /// \param Converted the list of template arguments provided for template
1856 /// parameters that precede \p Param in the template parameter list.
1858 /// \returns the substituted template argument, or NULL if an error occurred.
1859 static Sema::OwningExprResult
1860 SubstDefaultTemplateArgument(Sema &SemaRef,
1861 TemplateDecl *Template,
1862 SourceLocation TemplateLoc,
1863 SourceLocation RAngleLoc,
1864 NonTypeTemplateParmDecl *Param,
1865 TemplateArgumentListBuilder &Converted) {
1866 TemplateArgumentList TemplateArgs(SemaRef.Context, Converted,
1867 /*TakeArgs=*/false);
1869 MultiLevelTemplateArgumentList AllTemplateArgs
1870 = SemaRef.getTemplateInstantiationArgs(Template, &TemplateArgs);
1872 Sema::InstantiatingTemplate Inst(SemaRef, TemplateLoc,
1873 Template, Converted.getFlatArguments(),
1874 Converted.flatSize(),
1875 SourceRange(TemplateLoc, RAngleLoc));
1877 return SemaRef.SubstExpr(Param->getDefaultArgument(), AllTemplateArgs);
1880 /// \brief Substitute template arguments into the default template argument for
1881 /// the given template template parameter.
1883 /// \param SemaRef the semantic analysis object for which we are performing
1884 /// the substitution.
1886 /// \param Template the template that we are synthesizing template arguments
1889 /// \param TemplateLoc the location of the template name that started the
1890 /// template-id we are checking.
1892 /// \param RAngleLoc the location of the right angle bracket ('>') that
1893 /// terminates the template-id.
1895 /// \param Param the template template parameter whose default we are
1896 /// substituting into.
1898 /// \param Converted the list of template arguments provided for template
1899 /// parameters that precede \p Param in the template parameter list.
1901 /// \returns the substituted template argument, or NULL if an error occurred.
1903 SubstDefaultTemplateArgument(Sema &SemaRef,
1904 TemplateDecl *Template,
1905 SourceLocation TemplateLoc,
1906 SourceLocation RAngleLoc,
1907 TemplateTemplateParmDecl *Param,
1908 TemplateArgumentListBuilder &Converted) {
1909 TemplateArgumentList TemplateArgs(SemaRef.Context, Converted,
1910 /*TakeArgs=*/false);
1912 MultiLevelTemplateArgumentList AllTemplateArgs
1913 = SemaRef.getTemplateInstantiationArgs(Template, &TemplateArgs);
1915 Sema::InstantiatingTemplate Inst(SemaRef, TemplateLoc,
1916 Template, Converted.getFlatArguments(),
1917 Converted.flatSize(),
1918 SourceRange(TemplateLoc, RAngleLoc));
1920 return SemaRef.SubstTemplateName(
1921 Param->getDefaultArgument().getArgument().getAsTemplate(),
1922 Param->getDefaultArgument().getTemplateNameLoc(),
1926 /// \brief If the given template parameter has a default template
1927 /// argument, substitute into that default template argument and
1928 /// return the corresponding template argument.
1930 Sema::SubstDefaultTemplateArgumentIfAvailable(TemplateDecl *Template,
1931 SourceLocation TemplateLoc,
1932 SourceLocation RAngleLoc,
1934 TemplateArgumentListBuilder &Converted) {
1935 if (TemplateTypeParmDecl *TypeParm = dyn_cast<TemplateTypeParmDecl>(Param)) {
1936 if (!TypeParm->hasDefaultArgument())
1937 return TemplateArgumentLoc();
1939 TypeSourceInfo *DI = SubstDefaultTemplateArgument(*this, Template,
1945 return TemplateArgumentLoc(TemplateArgument(DI->getType()), DI);
1947 return TemplateArgumentLoc();
1950 if (NonTypeTemplateParmDecl *NonTypeParm
1951 = dyn_cast<NonTypeTemplateParmDecl>(Param)) {
1952 if (!NonTypeParm->hasDefaultArgument())
1953 return TemplateArgumentLoc();
1955 OwningExprResult Arg = SubstDefaultTemplateArgument(*this, Template,
1960 if (Arg.isInvalid())
1961 return TemplateArgumentLoc();
1963 Expr *ArgE = Arg.takeAs<Expr>();
1964 return TemplateArgumentLoc(TemplateArgument(ArgE), ArgE);
1967 TemplateTemplateParmDecl *TempTempParm
1968 = cast<TemplateTemplateParmDecl>(Param);
1969 if (!TempTempParm->hasDefaultArgument())
1970 return TemplateArgumentLoc();
1972 TemplateName TName = SubstDefaultTemplateArgument(*this, Template,
1978 return TemplateArgumentLoc();
1980 return TemplateArgumentLoc(TemplateArgument(TName),
1981 TempTempParm->getDefaultArgument().getTemplateQualifierRange(),
1982 TempTempParm->getDefaultArgument().getTemplateNameLoc());
1985 /// \brief Check that the given template argument corresponds to the given
1986 /// template parameter.
1987 bool Sema::CheckTemplateArgument(NamedDecl *Param,
1988 const TemplateArgumentLoc &Arg,
1989 TemplateDecl *Template,
1990 SourceLocation TemplateLoc,
1991 SourceLocation RAngleLoc,
1992 TemplateArgumentListBuilder &Converted,
1993 CheckTemplateArgumentKind CTAK) {
1994 // Check template type parameters.
1995 if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(Param))
1996 return CheckTemplateTypeArgument(TTP, Arg, Converted);
1998 // Check non-type template parameters.
1999 if (NonTypeTemplateParmDecl *NTTP =dyn_cast<NonTypeTemplateParmDecl>(Param)) {
2000 // Do substitution on the type of the non-type template parameter
2001 // with the template arguments we've seen thus far.
2002 QualType NTTPType = NTTP->getType();
2003 if (NTTPType->isDependentType()) {
2004 // Do substitution on the type of the non-type template parameter.
2005 InstantiatingTemplate Inst(*this, TemplateLoc, Template,
2006 NTTP, Converted.getFlatArguments(),
2007 Converted.flatSize(),
2008 SourceRange(TemplateLoc, RAngleLoc));
2010 TemplateArgumentList TemplateArgs(Context, Converted,
2011 /*TakeArgs=*/false);
2012 NTTPType = SubstType(NTTPType,
2013 MultiLevelTemplateArgumentList(TemplateArgs),
2014 NTTP->getLocation(),
2015 NTTP->getDeclName());
2016 // If that worked, check the non-type template parameter type
2018 if (!NTTPType.isNull())
2019 NTTPType = CheckNonTypeTemplateParameterType(NTTPType,
2020 NTTP->getLocation());
2021 if (NTTPType.isNull())
2025 switch (Arg.getArgument().getKind()) {
2026 case TemplateArgument::Null:
2027 assert(false && "Should never see a NULL template argument here");
2030 case TemplateArgument::Expression: {
2031 Expr *E = Arg.getArgument().getAsExpr();
2032 TemplateArgument Result;
2033 if (CheckTemplateArgument(NTTP, NTTPType, E, Result, CTAK))
2036 Converted.Append(Result);
2040 case TemplateArgument::Declaration:
2041 case TemplateArgument::Integral:
2042 // We've already checked this template argument, so just copy
2043 // it to the list of converted arguments.
2044 Converted.Append(Arg.getArgument());
2047 case TemplateArgument::Template:
2048 // We were given a template template argument. It may not be ill-formed;
2050 if (DependentTemplateName *DTN
2051 = Arg.getArgument().getAsTemplate().getAsDependentTemplateName()) {
2052 // We have a template argument such as \c T::template X, which we
2053 // parsed as a template template argument. However, since we now
2054 // know that we need a non-type template argument, convert this
2055 // template name into an expression.
2056 Expr *E = DependentScopeDeclRefExpr::Create(Context,
2057 DTN->getQualifier(),
2058 Arg.getTemplateQualifierRange(),
2059 DTN->getIdentifier(),
2060 Arg.getTemplateNameLoc());
2062 TemplateArgument Result;
2063 if (CheckTemplateArgument(NTTP, NTTPType, E, Result))
2066 Converted.Append(Result);
2070 // We have a template argument that actually does refer to a class
2071 // template, template alias, or template template parameter, and
2072 // therefore cannot be a non-type template argument.
2073 Diag(Arg.getLocation(), diag::err_template_arg_must_be_expr)
2074 << Arg.getSourceRange();
2076 Diag(Param->getLocation(), diag::note_template_param_here);
2079 case TemplateArgument::Type: {
2080 // We have a non-type template parameter but the template
2081 // argument is a type.
2083 // C++ [temp.arg]p2:
2084 // In a template-argument, an ambiguity between a type-id and
2085 // an expression is resolved to a type-id, regardless of the
2086 // form of the corresponding template-parameter.
2088 // We warn specifically about this case, since it can be rather
2089 // confusing for users.
2090 QualType T = Arg.getArgument().getAsType();
2091 SourceRange SR = Arg.getSourceRange();
2092 if (T->isFunctionType())
2093 Diag(SR.getBegin(), diag::err_template_arg_nontype_ambig) << SR << T;
2095 Diag(SR.getBegin(), diag::err_template_arg_must_be_expr) << SR;
2096 Diag(Param->getLocation(), diag::note_template_param_here);
2100 case TemplateArgument::Pack:
2101 llvm_unreachable("Caller must expand template argument packs");
2109 // Check template template parameters.
2110 TemplateTemplateParmDecl *TempParm = cast<TemplateTemplateParmDecl>(Param);
2112 // Substitute into the template parameter list of the template
2113 // template parameter, since previously-supplied template arguments
2114 // may appear within the template template parameter.
2116 // Set up a template instantiation context.
2117 LocalInstantiationScope Scope(*this);
2118 InstantiatingTemplate Inst(*this, TemplateLoc, Template,
2119 TempParm, Converted.getFlatArguments(),
2120 Converted.flatSize(),
2121 SourceRange(TemplateLoc, RAngleLoc));
2123 TemplateArgumentList TemplateArgs(Context, Converted,
2124 /*TakeArgs=*/false);
2125 TempParm = cast_or_null<TemplateTemplateParmDecl>(
2126 SubstDecl(TempParm, CurContext,
2127 MultiLevelTemplateArgumentList(TemplateArgs)));
2131 // FIXME: TempParam is leaked.
2134 switch (Arg.getArgument().getKind()) {
2135 case TemplateArgument::Null:
2136 assert(false && "Should never see a NULL template argument here");
2139 case TemplateArgument::Template:
2140 if (CheckTemplateArgument(TempParm, Arg))
2143 Converted.Append(Arg.getArgument());
2146 case TemplateArgument::Expression:
2147 case TemplateArgument::Type:
2148 // We have a template template parameter but the template
2149 // argument does not refer to a template.
2150 Diag(Arg.getLocation(), diag::err_template_arg_must_be_template);
2153 case TemplateArgument::Declaration:
2155 "Declaration argument with template template parameter");
2157 case TemplateArgument::Integral:
2159 "Integral argument with template template parameter");
2162 case TemplateArgument::Pack:
2163 llvm_unreachable("Caller must expand template argument packs");
2170 /// \brief Check that the given template argument list is well-formed
2171 /// for specializing the given template.
2172 bool Sema::CheckTemplateArgumentList(TemplateDecl *Template,
2173 SourceLocation TemplateLoc,
2174 const TemplateArgumentListInfo &TemplateArgs,
2175 bool PartialTemplateArgs,
2176 TemplateArgumentListBuilder &Converted) {
2177 TemplateParameterList *Params = Template->getTemplateParameters();
2178 unsigned NumParams = Params->size();
2179 unsigned NumArgs = TemplateArgs.size();
2180 bool Invalid = false;
2182 SourceLocation RAngleLoc = TemplateArgs.getRAngleLoc();
2184 bool HasParameterPack =
2185 NumParams > 0 && Params->getParam(NumParams - 1)->isTemplateParameterPack();
2187 if ((NumArgs > NumParams && !HasParameterPack) ||
2188 (NumArgs < Params->getMinRequiredArguments() &&
2189 !PartialTemplateArgs)) {
2190 // FIXME: point at either the first arg beyond what we can handle,
2191 // or the '>', depending on whether we have too many or too few
2194 if (NumArgs > NumParams)
2195 Range = SourceRange(TemplateArgs[NumParams].getLocation(), RAngleLoc);
2196 Diag(TemplateLoc, diag::err_template_arg_list_different_arity)
2197 << (NumArgs > NumParams)
2198 << (isa<ClassTemplateDecl>(Template)? 0 :
2199 isa<FunctionTemplateDecl>(Template)? 1 :
2200 isa<TemplateTemplateParmDecl>(Template)? 2 : 3)
2201 << Template << Range;
2202 Diag(Template->getLocation(), diag::note_template_decl_here)
2203 << Params->getSourceRange();
2207 // C++ [temp.arg]p1:
2208 // [...] The type and form of each template-argument specified in
2209 // a template-id shall match the type and form specified for the
2210 // corresponding parameter declared by the template in its
2211 // template-parameter-list.
2212 unsigned ArgIdx = 0;
2213 for (TemplateParameterList::iterator Param = Params->begin(),
2214 ParamEnd = Params->end();
2215 Param != ParamEnd; ++Param, ++ArgIdx) {
2216 if (ArgIdx > NumArgs && PartialTemplateArgs)
2219 // If we have a template parameter pack, check every remaining template
2220 // argument against that template parameter pack.
2221 if ((*Param)->isTemplateParameterPack()) {
2222 Converted.BeginPack();
2223 for (; ArgIdx < NumArgs; ++ArgIdx) {
2224 if (CheckTemplateArgument(*Param, TemplateArgs[ArgIdx], Template,
2225 TemplateLoc, RAngleLoc, Converted)) {
2230 Converted.EndPack();
2234 if (ArgIdx < NumArgs) {
2235 // Check the template argument we were given.
2236 if (CheckTemplateArgument(*Param, TemplateArgs[ArgIdx], Template,
2237 TemplateLoc, RAngleLoc, Converted))
2243 // We have a default template argument that we will use.
2244 TemplateArgumentLoc Arg;
2246 // Retrieve the default template argument from the template
2247 // parameter. For each kind of template parameter, we substitute the
2248 // template arguments provided thus far and any "outer" template arguments
2249 // (when the template parameter was part of a nested template) into
2250 // the default argument.
2251 if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(*Param)) {
2252 if (!TTP->hasDefaultArgument()) {
2253 assert((Invalid || PartialTemplateArgs) && "Missing default argument");
2257 TypeSourceInfo *ArgType = SubstDefaultTemplateArgument(*this,
2266 Arg = TemplateArgumentLoc(TemplateArgument(ArgType->getType()),
2268 } else if (NonTypeTemplateParmDecl *NTTP
2269 = dyn_cast<NonTypeTemplateParmDecl>(*Param)) {
2270 if (!NTTP->hasDefaultArgument()) {
2271 assert((Invalid || PartialTemplateArgs) && "Missing default argument");
2275 Sema::OwningExprResult E = SubstDefaultTemplateArgument(*this, Template,
2283 Expr *Ex = E.takeAs<Expr>();
2284 Arg = TemplateArgumentLoc(TemplateArgument(Ex), Ex);
2286 TemplateTemplateParmDecl *TempParm
2287 = cast<TemplateTemplateParmDecl>(*Param);
2289 if (!TempParm->hasDefaultArgument()) {
2290 assert((Invalid || PartialTemplateArgs) && "Missing default argument");
2294 TemplateName Name = SubstDefaultTemplateArgument(*this, Template,
2302 Arg = TemplateArgumentLoc(TemplateArgument(Name),
2303 TempParm->getDefaultArgument().getTemplateQualifierRange(),
2304 TempParm->getDefaultArgument().getTemplateNameLoc());
2307 // Introduce an instantiation record that describes where we are using
2308 // the default template argument.
2309 InstantiatingTemplate Instantiating(*this, RAngleLoc, Template, *Param,
2310 Converted.getFlatArguments(),
2311 Converted.flatSize(),
2312 SourceRange(TemplateLoc, RAngleLoc));
2314 // Check the default template argument.
2315 if (CheckTemplateArgument(*Param, Arg, Template, TemplateLoc,
2316 RAngleLoc, Converted))
2323 /// \brief Check a template argument against its corresponding
2324 /// template type parameter.
2326 /// This routine implements the semantics of C++ [temp.arg.type]. It
2327 /// returns true if an error occurred, and false otherwise.
2328 bool Sema::CheckTemplateArgument(TemplateTypeParmDecl *Param,
2329 TypeSourceInfo *ArgInfo) {
2330 assert(ArgInfo && "invalid TypeSourceInfo");
2331 QualType Arg = ArgInfo->getType();
2333 // C++ [temp.arg.type]p2:
2334 // A local type, a type with no linkage, an unnamed type or a type
2335 // compounded from any of these types shall not be used as a
2336 // template-argument for a template type-parameter.
2338 // FIXME: Perform the unnamed type check.
2339 SourceRange SR = ArgInfo->getTypeLoc().getSourceRange();
2340 const TagType *Tag = 0;
2341 if (const EnumType *EnumT = Arg->getAs<EnumType>())
2343 else if (const RecordType *RecordT = Arg->getAs<RecordType>())
2345 if (Tag && Tag->getDecl()->getDeclContext()->isFunctionOrMethod()) {
2346 SourceRange SR = ArgInfo->getTypeLoc().getSourceRange();
2347 return Diag(SR.getBegin(), diag::err_template_arg_local_type)
2348 << QualType(Tag, 0) << SR;
2349 } else if (Tag && !Tag->getDecl()->getDeclName() &&
2350 !Tag->getDecl()->getTypedefForAnonDecl()) {
2351 Diag(SR.getBegin(), diag::err_template_arg_unnamed_type) << SR;
2352 Diag(Tag->getDecl()->getLocation(), diag::note_template_unnamed_type_here);
2354 } else if (Arg->isVariablyModifiedType()) {
2355 Diag(SR.getBegin(), diag::err_variably_modified_template_arg)
2358 } else if (Context.hasSameUnqualifiedType(Arg, Context.OverloadTy)) {
2359 return Diag(SR.getBegin(), diag::err_template_arg_overload_type) << SR;
2365 /// \brief Checks whether the given template argument is the address
2366 /// of an object or function according to C++ [temp.arg.nontype]p1.
2368 CheckTemplateArgumentAddressOfObjectOrFunction(Sema &S,
2369 NonTypeTemplateParmDecl *Param,
2372 TemplateArgument &Converted) {
2373 bool Invalid = false;
2375 QualType ArgType = Arg->getType();
2377 // See through any implicit casts we added to fix the type.
2378 while (ImplicitCastExpr *Cast = dyn_cast<ImplicitCastExpr>(Arg))
2379 Arg = Cast->getSubExpr();
2381 // C++ [temp.arg.nontype]p1:
2383 // A template-argument for a non-type, non-template
2384 // template-parameter shall be one of: [...]
2386 // -- the address of an object or function with external
2387 // linkage, including function templates and function
2388 // template-ids but excluding non-static class members,
2389 // expressed as & id-expression where the & is optional if
2390 // the name refers to a function or array, or if the
2391 // corresponding template-parameter is a reference; or
2392 DeclRefExpr *DRE = 0;
2394 // Ignore (and complain about) any excess parentheses.
2395 while (ParenExpr *Parens = dyn_cast<ParenExpr>(Arg)) {
2397 S.Diag(Arg->getSourceRange().getBegin(),
2398 diag::err_template_arg_extra_parens)
2399 << Arg->getSourceRange();
2403 Arg = Parens->getSubExpr();
2406 bool AddressTaken = false;
2407 SourceLocation AddrOpLoc;
2408 if (UnaryOperator *UnOp = dyn_cast<UnaryOperator>(Arg)) {
2409 if (UnOp->getOpcode() == UnaryOperator::AddrOf) {
2410 DRE = dyn_cast<DeclRefExpr>(UnOp->getSubExpr());
2411 AddressTaken = true;
2412 AddrOpLoc = UnOp->getOperatorLoc();
2415 DRE = dyn_cast<DeclRefExpr>(Arg);
2418 S.Diag(Arg->getLocStart(), diag::err_template_arg_not_decl_ref)
2419 << Arg->getSourceRange();
2420 S.Diag(Param->getLocation(), diag::note_template_param_here);
2424 // Stop checking the precise nature of the argument if it is value dependent,
2425 // it should be checked when instantiated.
2426 if (Arg->isValueDependent()) {
2427 Converted = TemplateArgument(ArgIn->Retain());
2431 if (!isa<ValueDecl>(DRE->getDecl())) {
2432 S.Diag(Arg->getSourceRange().getBegin(),
2433 diag::err_template_arg_not_object_or_func_form)
2434 << Arg->getSourceRange();
2435 S.Diag(Param->getLocation(), diag::note_template_param_here);
2439 NamedDecl *Entity = 0;
2441 // Cannot refer to non-static data members
2442 if (FieldDecl *Field = dyn_cast<FieldDecl>(DRE->getDecl())) {
2443 S.Diag(Arg->getSourceRange().getBegin(), diag::err_template_arg_field)
2444 << Field << Arg->getSourceRange();
2445 S.Diag(Param->getLocation(), diag::note_template_param_here);
2449 // Cannot refer to non-static member functions
2450 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(DRE->getDecl()))
2451 if (!Method->isStatic()) {
2452 S.Diag(Arg->getSourceRange().getBegin(), diag::err_template_arg_method)
2453 << Method << Arg->getSourceRange();
2454 S.Diag(Param->getLocation(), diag::note_template_param_here);
2458 // Functions must have external linkage.
2459 if (FunctionDecl *Func = dyn_cast<FunctionDecl>(DRE->getDecl())) {
2460 if (!isExternalLinkage(Func->getLinkage())) {
2461 S.Diag(Arg->getSourceRange().getBegin(),
2462 diag::err_template_arg_function_not_extern)
2463 << Func << Arg->getSourceRange();
2464 S.Diag(Func->getLocation(), diag::note_template_arg_internal_object)
2469 // Okay: we've named a function with external linkage.
2472 // If the template parameter has pointer type, the function decays.
2473 if (ParamType->isPointerType() && !AddressTaken)
2474 ArgType = S.Context.getPointerType(Func->getType());
2475 else if (AddressTaken && ParamType->isReferenceType()) {
2476 // If we originally had an address-of operator, but the
2477 // parameter has reference type, complain and (if things look
2478 // like they will work) drop the address-of operator.
2479 if (!S.Context.hasSameUnqualifiedType(Func->getType(),
2480 ParamType.getNonReferenceType())) {
2481 S.Diag(AddrOpLoc, diag::err_template_arg_address_of_non_pointer)
2483 S.Diag(Param->getLocation(), diag::note_template_param_here);
2487 S.Diag(AddrOpLoc, diag::err_template_arg_address_of_non_pointer)
2489 << FixItHint::CreateRemoval(AddrOpLoc);
2490 S.Diag(Param->getLocation(), diag::note_template_param_here);
2492 ArgType = Func->getType();
2494 } else if (VarDecl *Var = dyn_cast<VarDecl>(DRE->getDecl())) {
2495 if (!isExternalLinkage(Var->getLinkage())) {
2496 S.Diag(Arg->getSourceRange().getBegin(),
2497 diag::err_template_arg_object_not_extern)
2498 << Var << Arg->getSourceRange();
2499 S.Diag(Var->getLocation(), diag::note_template_arg_internal_object)
2504 // A value of reference type is not an object.
2505 if (Var->getType()->isReferenceType()) {
2506 S.Diag(Arg->getSourceRange().getBegin(),
2507 diag::err_template_arg_reference_var)
2508 << Var->getType() << Arg->getSourceRange();
2509 S.Diag(Param->getLocation(), diag::note_template_param_here);
2513 // Okay: we've named an object with external linkage
2516 // If the template parameter has pointer type, we must have taken
2517 // the address of this object.
2518 if (ParamType->isReferenceType()) {
2520 // If we originally had an address-of operator, but the
2521 // parameter has reference type, complain and (if things look
2522 // like they will work) drop the address-of operator.
2523 if (!S.Context.hasSameUnqualifiedType(Var->getType(),
2524 ParamType.getNonReferenceType())) {
2525 S.Diag(AddrOpLoc, diag::err_template_arg_address_of_non_pointer)
2527 S.Diag(Param->getLocation(), diag::note_template_param_here);
2531 S.Diag(AddrOpLoc, diag::err_template_arg_address_of_non_pointer)
2533 << FixItHint::CreateRemoval(AddrOpLoc);
2534 S.Diag(Param->getLocation(), diag::note_template_param_here);
2536 ArgType = Var->getType();
2538 } else if (!AddressTaken && ParamType->isPointerType()) {
2539 if (Var->getType()->isArrayType()) {
2540 // Array-to-pointer decay.
2541 ArgType = S.Context.getArrayDecayedType(Var->getType());
2543 // If the template parameter has pointer type but the address of
2544 // this object was not taken, complain and (possibly) recover by
2545 // taking the address of the entity.
2546 ArgType = S.Context.getPointerType(Var->getType());
2547 if (!S.Context.hasSameUnqualifiedType(ArgType, ParamType)) {
2548 S.Diag(Arg->getLocStart(), diag::err_template_arg_not_address_of)
2550 S.Diag(Param->getLocation(), diag::note_template_param_here);
2554 S.Diag(Arg->getLocStart(), diag::err_template_arg_not_address_of)
2556 << FixItHint::CreateInsertion(Arg->getLocStart(), "&");
2558 S.Diag(Param->getLocation(), diag::note_template_param_here);
2562 // We found something else, but we don't know specifically what it is.
2563 S.Diag(Arg->getSourceRange().getBegin(),
2564 diag::err_template_arg_not_object_or_func)
2565 << Arg->getSourceRange();
2566 S.Diag(DRE->getDecl()->getLocation(), diag::note_template_arg_refers_here);
2570 if (ParamType->isPointerType() &&
2571 !ParamType->getAs<PointerType>()->getPointeeType()->isFunctionType() &&
2572 S.IsQualificationConversion(ArgType, ParamType)) {
2573 // For pointer-to-object types, qualification conversions are
2576 if (const ReferenceType *ParamRef = ParamType->getAs<ReferenceType>()) {
2577 if (!ParamRef->getPointeeType()->isFunctionType()) {
2578 // C++ [temp.arg.nontype]p5b3:
2579 // For a non-type template-parameter of type reference to
2580 // object, no conversions apply. The type referred to by the
2581 // reference may be more cv-qualified than the (otherwise
2582 // identical) type of the template- argument. The
2583 // template-parameter is bound directly to the
2584 // template-argument, which shall be an lvalue.
2586 // FIXME: Other qualifiers?
2587 unsigned ParamQuals = ParamRef->getPointeeType().getCVRQualifiers();
2588 unsigned ArgQuals = ArgType.getCVRQualifiers();
2590 if ((ParamQuals | ArgQuals) != ParamQuals) {
2591 S.Diag(Arg->getSourceRange().getBegin(),
2592 diag::err_template_arg_ref_bind_ignores_quals)
2593 << ParamType << Arg->getType()
2594 << Arg->getSourceRange();
2595 S.Diag(Param->getLocation(), diag::note_template_param_here);
2601 // At this point, the template argument refers to an object or
2602 // function with external linkage. We now need to check whether the
2603 // argument and parameter types are compatible.
2604 if (!S.Context.hasSameUnqualifiedType(ArgType,
2605 ParamType.getNonReferenceType())) {
2606 // We can't perform this conversion or binding.
2607 if (ParamType->isReferenceType())
2608 S.Diag(Arg->getLocStart(), diag::err_template_arg_no_ref_bind)
2609 << ParamType << Arg->getType() << Arg->getSourceRange();
2611 S.Diag(Arg->getLocStart(), diag::err_template_arg_not_convertible)
2612 << Arg->getType() << ParamType << Arg->getSourceRange();
2613 S.Diag(Param->getLocation(), diag::note_template_param_here);
2618 // Create the template argument.
2619 Converted = TemplateArgument(Entity->getCanonicalDecl());
2620 S.MarkDeclarationReferenced(Arg->getLocStart(), Entity);
2624 /// \brief Checks whether the given template argument is a pointer to
2625 /// member constant according to C++ [temp.arg.nontype]p1.
2626 bool Sema::CheckTemplateArgumentPointerToMember(Expr *Arg,
2627 TemplateArgument &Converted) {
2628 bool Invalid = false;
2630 // See through any implicit casts we added to fix the type.
2631 while (ImplicitCastExpr *Cast = dyn_cast<ImplicitCastExpr>(Arg))
2632 Arg = Cast->getSubExpr();
2634 // C++ [temp.arg.nontype]p1:
2636 // A template-argument for a non-type, non-template
2637 // template-parameter shall be one of: [...]
2639 // -- a pointer to member expressed as described in 5.3.1.
2640 DeclRefExpr *DRE = 0;
2642 // Ignore (and complain about) any excess parentheses.
2643 while (ParenExpr *Parens = dyn_cast<ParenExpr>(Arg)) {
2645 Diag(Arg->getSourceRange().getBegin(),
2646 diag::err_template_arg_extra_parens)
2647 << Arg->getSourceRange();
2651 Arg = Parens->getSubExpr();
2654 // A pointer-to-member constant written &Class::member.
2655 if (UnaryOperator *UnOp = dyn_cast<UnaryOperator>(Arg)) {
2656 if (UnOp->getOpcode() == UnaryOperator::AddrOf) {
2657 DRE = dyn_cast<DeclRefExpr>(UnOp->getSubExpr());
2658 if (DRE && !DRE->getQualifier())
2662 // A constant of pointer-to-member type.
2663 else if ((DRE = dyn_cast<DeclRefExpr>(Arg))) {
2664 if (ValueDecl *VD = dyn_cast<ValueDecl>(DRE->getDecl())) {
2665 if (VD->getType()->isMemberPointerType()) {
2666 if (isa<NonTypeTemplateParmDecl>(VD) ||
2667 (isa<VarDecl>(VD) &&
2668 Context.getCanonicalType(VD->getType()).isConstQualified())) {
2669 if (Arg->isTypeDependent() || Arg->isValueDependent())
2670 Converted = TemplateArgument(Arg->Retain());
2672 Converted = TemplateArgument(VD->getCanonicalDecl());
2682 return Diag(Arg->getSourceRange().getBegin(),
2683 diag::err_template_arg_not_pointer_to_member_form)
2684 << Arg->getSourceRange();
2686 if (isa<FieldDecl>(DRE->getDecl()) || isa<CXXMethodDecl>(DRE->getDecl())) {
2687 assert((isa<FieldDecl>(DRE->getDecl()) ||
2688 !cast<CXXMethodDecl>(DRE->getDecl())->isStatic()) &&
2689 "Only non-static member pointers can make it here");
2691 // Okay: this is the address of a non-static member, and therefore
2692 // a member pointer constant.
2693 if (Arg->isTypeDependent() || Arg->isValueDependent())
2694 Converted = TemplateArgument(Arg->Retain());
2696 Converted = TemplateArgument(DRE->getDecl()->getCanonicalDecl());
2700 // We found something else, but we don't know specifically what it is.
2701 Diag(Arg->getSourceRange().getBegin(),
2702 diag::err_template_arg_not_pointer_to_member_form)
2703 << Arg->getSourceRange();
2704 Diag(DRE->getDecl()->getLocation(),
2705 diag::note_template_arg_refers_here);
2709 /// \brief Check a template argument against its corresponding
2710 /// non-type template parameter.
2712 /// This routine implements the semantics of C++ [temp.arg.nontype].
2713 /// It returns true if an error occurred, and false otherwise. \p
2714 /// InstantiatedParamType is the type of the non-type template
2715 /// parameter after it has been instantiated.
2717 /// If no error was detected, Converted receives the converted template argument.
2718 bool Sema::CheckTemplateArgument(NonTypeTemplateParmDecl *Param,
2719 QualType InstantiatedParamType, Expr *&Arg,
2720 TemplateArgument &Converted,
2721 CheckTemplateArgumentKind CTAK) {
2722 SourceLocation StartLoc = Arg->getSourceRange().getBegin();
2724 // If either the parameter has a dependent type or the argument is
2725 // type-dependent, there's nothing we can check now.
2726 if (InstantiatedParamType->isDependentType() || Arg->isTypeDependent()) {
2727 // FIXME: Produce a cloned, canonical expression?
2728 Converted = TemplateArgument(Arg);
2732 // C++ [temp.arg.nontype]p5:
2733 // The following conversions are performed on each expression used
2734 // as a non-type template-argument. If a non-type
2735 // template-argument cannot be converted to the type of the
2736 // corresponding template-parameter then the program is
2739 // -- for a non-type template-parameter of integral or
2740 // enumeration type, integral promotions (4.5) and integral
2741 // conversions (4.7) are applied.
2742 QualType ParamType = InstantiatedParamType;
2743 QualType ArgType = Arg->getType();
2744 if (ParamType->isIntegralOrEnumerationType()) {
2745 // C++ [temp.arg.nontype]p1:
2746 // A template-argument for a non-type, non-template
2747 // template-parameter shall be one of:
2749 // -- an integral constant-expression of integral or enumeration
2751 // -- the name of a non-type template-parameter; or
2752 SourceLocation NonConstantLoc;
2754 if (!ArgType->isIntegralOrEnumerationType()) {
2755 Diag(Arg->getSourceRange().getBegin(),
2756 diag::err_template_arg_not_integral_or_enumeral)
2757 << ArgType << Arg->getSourceRange();
2758 Diag(Param->getLocation(), diag::note_template_param_here);
2760 } else if (!Arg->isValueDependent() &&
2761 !Arg->isIntegerConstantExpr(Value, Context, &NonConstantLoc)) {
2762 Diag(NonConstantLoc, diag::err_template_arg_not_ice)
2763 << ArgType << Arg->getSourceRange();
2767 // From here on out, all we care about are the unqualified forms
2768 // of the parameter and argument types.
2769 ParamType = ParamType.getUnqualifiedType();
2770 ArgType = ArgType.getUnqualifiedType();
2772 // Try to convert the argument to the parameter's type.
2773 if (Context.hasSameType(ParamType, ArgType)) {
2774 // Okay: no conversion necessary
2775 } else if (CTAK == CTAK_Deduced) {
2776 // C++ [temp.deduct.type]p17:
2777 // If, in the declaration of a function template with a non-type
2778 // template-parameter, the non-type template- parameter is used
2779 // in an expression in the function parameter-list and, if the
2780 // corresponding template-argument is deduced, the
2781 // template-argument type shall match the type of the
2782 // template-parameter exactly, except that a template-argument
2783 // deduced from an array bound may be of any integral type.
2784 Diag(StartLoc, diag::err_deduced_non_type_template_arg_type_mismatch)
2785 << ArgType << ParamType;
2786 Diag(Param->getLocation(), diag::note_template_param_here);
2788 } else if (IsIntegralPromotion(Arg, ArgType, ParamType) ||
2789 !ParamType->isEnumeralType()) {
2790 // This is an integral promotion or conversion.
2791 ImpCastExprToType(Arg, ParamType, CastExpr::CK_IntegralCast);
2793 // We can't perform this conversion.
2794 Diag(Arg->getSourceRange().getBegin(),
2795 diag::err_template_arg_not_convertible)
2796 << Arg->getType() << InstantiatedParamType << Arg->getSourceRange();
2797 Diag(Param->getLocation(), diag::note_template_param_here);
2801 QualType IntegerType = Context.getCanonicalType(ParamType);
2802 if (const EnumType *Enum = IntegerType->getAs<EnumType>())
2803 IntegerType = Context.getCanonicalType(Enum->getDecl()->getIntegerType());
2805 if (!Arg->isValueDependent()) {
2806 llvm::APSInt OldValue = Value;
2808 // Coerce the template argument's value to the value it will have
2809 // based on the template parameter's type.
2810 unsigned AllowedBits = Context.getTypeSize(IntegerType);
2811 if (Value.getBitWidth() != AllowedBits)
2812 Value.extOrTrunc(AllowedBits);
2813 Value.setIsSigned(IntegerType->isSignedIntegerType());
2815 // Complain if an unsigned parameter received a negative value.
2816 if (IntegerType->isUnsignedIntegerType()
2817 && (OldValue.isSigned() && OldValue.isNegative())) {
2818 Diag(Arg->getSourceRange().getBegin(), diag::warn_template_arg_negative)
2819 << OldValue.toString(10) << Value.toString(10) << Param->getType()
2820 << Arg->getSourceRange();
2821 Diag(Param->getLocation(), diag::note_template_param_here);
2824 // Complain if we overflowed the template parameter's type.
2825 unsigned RequiredBits;
2826 if (IntegerType->isUnsignedIntegerType())
2827 RequiredBits = OldValue.getActiveBits();
2828 else if (OldValue.isUnsigned())
2829 RequiredBits = OldValue.getActiveBits() + 1;
2831 RequiredBits = OldValue.getMinSignedBits();
2832 if (RequiredBits > AllowedBits) {
2833 Diag(Arg->getSourceRange().getBegin(),
2834 diag::warn_template_arg_too_large)
2835 << OldValue.toString(10) << Value.toString(10) << Param->getType()
2836 << Arg->getSourceRange();
2837 Diag(Param->getLocation(), diag::note_template_param_here);
2841 // Add the value of this argument to the list of converted
2842 // arguments. We use the bitwidth and signedness of the template
2844 if (Arg->isValueDependent()) {
2845 // The argument is value-dependent. Create a new
2846 // TemplateArgument with the converted expression.
2847 Converted = TemplateArgument(Arg);
2851 Converted = TemplateArgument(Value,
2852 ParamType->isEnumeralType() ? ParamType
2857 DeclAccessPair FoundResult; // temporary for ResolveOverloadedFunction
2859 // C++0x [temp.arg.nontype]p5 bullets 2, 4 and 6 permit conversion
2860 // from a template argument of type std::nullptr_t to a non-type
2861 // template parameter of type pointer to object, pointer to
2862 // function, or pointer-to-member, respectively.
2863 if (ArgType->isNullPtrType() &&
2864 (ParamType->isPointerType() || ParamType->isMemberPointerType())) {
2865 Converted = TemplateArgument((NamedDecl *)0);
2869 // Handle pointer-to-function, reference-to-function, and
2870 // pointer-to-member-function all in (roughly) the same way.
2871 if (// -- For a non-type template-parameter of type pointer to
2872 // function, only the function-to-pointer conversion (4.3) is
2873 // applied. If the template-argument represents a set of
2874 // overloaded functions (or a pointer to such), the matching
2875 // function is selected from the set (13.4).
2876 (ParamType->isPointerType() &&
2877 ParamType->getAs<PointerType>()->getPointeeType()->isFunctionType()) ||
2878 // -- For a non-type template-parameter of type reference to
2879 // function, no conversions apply. If the template-argument
2880 // represents a set of overloaded functions, the matching
2881 // function is selected from the set (13.4).
2882 (ParamType->isReferenceType() &&
2883 ParamType->getAs<ReferenceType>()->getPointeeType()->isFunctionType()) ||
2884 // -- For a non-type template-parameter of type pointer to
2885 // member function, no conversions apply. If the
2886 // template-argument represents a set of overloaded member
2887 // functions, the matching member function is selected from
2889 (ParamType->isMemberPointerType() &&
2890 ParamType->getAs<MemberPointerType>()->getPointeeType()
2891 ->isFunctionType())) {
2893 if (Arg->getType() == Context.OverloadTy) {
2894 if (FunctionDecl *Fn = ResolveAddressOfOverloadedFunction(Arg, ParamType,
2897 if (DiagnoseUseOfDecl(Fn, Arg->getSourceRange().getBegin()))
2900 Arg = FixOverloadedFunctionReference(Arg, FoundResult, Fn);
2901 ArgType = Arg->getType();
2906 if (!ParamType->isMemberPointerType())
2907 return CheckTemplateArgumentAddressOfObjectOrFunction(*this, Param,
2911 if (IsQualificationConversion(ArgType, ParamType.getNonReferenceType())) {
2912 ImpCastExprToType(Arg, ParamType, CastExpr::CK_NoOp,
2913 Arg->isLvalue(Context) == Expr::LV_Valid);
2914 } else if (!Context.hasSameUnqualifiedType(ArgType,
2915 ParamType.getNonReferenceType())) {
2916 // We can't perform this conversion.
2917 Diag(Arg->getSourceRange().getBegin(),
2918 diag::err_template_arg_not_convertible)
2919 << Arg->getType() << InstantiatedParamType << Arg->getSourceRange();
2920 Diag(Param->getLocation(), diag::note_template_param_here);
2924 return CheckTemplateArgumentPointerToMember(Arg, Converted);
2927 if (ParamType->isPointerType()) {
2928 // -- for a non-type template-parameter of type pointer to
2929 // object, qualification conversions (4.4) and the
2930 // array-to-pointer conversion (4.2) are applied.
2931 // C++0x also allows a value of std::nullptr_t.
2932 assert(ParamType->getAs<PointerType>()->getPointeeType()->isObjectType() &&
2933 "Only object pointers allowed here");
2935 return CheckTemplateArgumentAddressOfObjectOrFunction(*this, Param,
2940 if (const ReferenceType *ParamRefType = ParamType->getAs<ReferenceType>()) {
2941 // -- For a non-type template-parameter of type reference to
2942 // object, no conversions apply. The type referred to by the
2943 // reference may be more cv-qualified than the (otherwise
2944 // identical) type of the template-argument. The
2945 // template-parameter is bound directly to the
2946 // template-argument, which must be an lvalue.
2947 assert(ParamRefType->getPointeeType()->isObjectType() &&
2948 "Only object references allowed here");
2950 if (Arg->getType() == Context.OverloadTy) {
2951 if (FunctionDecl *Fn = ResolveAddressOfOverloadedFunction(Arg,
2952 ParamRefType->getPointeeType(),
2955 if (DiagnoseUseOfDecl(Fn, Arg->getSourceRange().getBegin()))
2958 Arg = FixOverloadedFunctionReference(Arg, FoundResult, Fn);
2959 ArgType = Arg->getType();
2964 return CheckTemplateArgumentAddressOfObjectOrFunction(*this, Param,
2969 // -- For a non-type template-parameter of type pointer to data
2970 // member, qualification conversions (4.4) are applied.
2971 assert(ParamType->isMemberPointerType() && "Only pointers to members remain");
2973 if (Context.hasSameUnqualifiedType(ParamType, ArgType)) {
2974 // Types match exactly: nothing more to do here.
2975 } else if (IsQualificationConversion(ArgType, ParamType)) {
2976 ImpCastExprToType(Arg, ParamType, CastExpr::CK_NoOp,
2977 Arg->isLvalue(Context) == Expr::LV_Valid);
2979 // We can't perform this conversion.
2980 Diag(Arg->getSourceRange().getBegin(),
2981 diag::err_template_arg_not_convertible)
2982 << Arg->getType() << InstantiatedParamType << Arg->getSourceRange();
2983 Diag(Param->getLocation(), diag::note_template_param_here);
2987 return CheckTemplateArgumentPointerToMember(Arg, Converted);
2990 /// \brief Check a template argument against its corresponding
2991 /// template template parameter.
2993 /// This routine implements the semantics of C++ [temp.arg.template].
2994 /// It returns true if an error occurred, and false otherwise.
2995 bool Sema::CheckTemplateArgument(TemplateTemplateParmDecl *Param,
2996 const TemplateArgumentLoc &Arg) {
2997 TemplateName Name = Arg.getArgument().getAsTemplate();
2998 TemplateDecl *Template = Name.getAsTemplateDecl();
3000 // Any dependent template name is fine.
3001 assert(Name.isDependent() && "Non-dependent template isn't a declaration?");
3005 // C++ [temp.arg.template]p1:
3006 // A template-argument for a template template-parameter shall be
3007 // the name of a class template, expressed as id-expression. Only
3008 // primary class templates are considered when matching the
3009 // template template argument with the corresponding parameter;
3010 // partial specializations are not considered even if their
3011 // parameter lists match that of the template template parameter.
3013 // Note that we also allow template template parameters here, which
3014 // will happen when we are dealing with, e.g., class template
3015 // partial specializations.
3016 if (!isa<ClassTemplateDecl>(Template) &&
3017 !isa<TemplateTemplateParmDecl>(Template)) {
3018 assert(isa<FunctionTemplateDecl>(Template) &&
3019 "Only function templates are possible here");
3020 Diag(Arg.getLocation(), diag::err_template_arg_not_class_template);
3021 Diag(Template->getLocation(), diag::note_template_arg_refers_here_func)
3025 return !TemplateParameterListsAreEqual(Template->getTemplateParameters(),
3026 Param->getTemplateParameters(),
3028 TPL_TemplateTemplateArgumentMatch,
3032 /// \brief Given a non-type template argument that refers to a
3033 /// declaration and the type of its corresponding non-type template
3034 /// parameter, produce an expression that properly refers to that
3036 Sema::OwningExprResult
3037 Sema::BuildExpressionFromDeclTemplateArgument(const TemplateArgument &Arg,
3039 SourceLocation Loc) {
3040 assert(Arg.getKind() == TemplateArgument::Declaration &&
3041 "Only declaration template arguments permitted here");
3042 ValueDecl *VD = cast<ValueDecl>(Arg.getAsDecl());
3044 if (VD->getDeclContext()->isRecord() &&
3045 (isa<CXXMethodDecl>(VD) || isa<FieldDecl>(VD))) {
3046 // If the value is a class member, we might have a pointer-to-member.
3047 // Determine whether the non-type template template parameter is of
3048 // pointer-to-member type. If so, we need to build an appropriate
3049 // expression for a pointer-to-member, since a "normal" DeclRefExpr
3050 // would refer to the member itself.
3051 if (ParamType->isMemberPointerType()) {
3053 = Context.getTypeDeclType(cast<RecordDecl>(VD->getDeclContext()));
3054 NestedNameSpecifier *Qualifier
3055 = NestedNameSpecifier::Create(Context, 0, false, ClassType.getTypePtr());
3057 SS.setScopeRep(Qualifier);
3058 OwningExprResult RefExpr = BuildDeclRefExpr(VD,
3059 VD->getType().getNonReferenceType(),
3062 if (RefExpr.isInvalid())
3065 RefExpr = CreateBuiltinUnaryOp(Loc, UnaryOperator::AddrOf, move(RefExpr));
3067 // We might need to perform a trailing qualification conversion, since
3068 // the element type on the parameter could be more qualified than the
3069 // element type in the expression we constructed.
3070 if (IsQualificationConversion(((Expr*) RefExpr.get())->getType(),
3071 ParamType.getUnqualifiedType())) {
3072 Expr *RefE = RefExpr.takeAs<Expr>();
3073 ImpCastExprToType(RefE, ParamType.getUnqualifiedType(),
3075 RefExpr = Owned(RefE);
3078 assert(!RefExpr.isInvalid() &&
3079 Context.hasSameType(((Expr*) RefExpr.get())->getType(),
3080 ParamType.getUnqualifiedType()));
3081 return move(RefExpr);
3085 QualType T = VD->getType().getNonReferenceType();
3086 if (ParamType->isPointerType()) {
3087 // When the non-type template parameter is a pointer, take the
3088 // address of the declaration.
3089 OwningExprResult RefExpr = BuildDeclRefExpr(VD, T, Loc);
3090 if (RefExpr.isInvalid())
3093 if (T->isFunctionType() || T->isArrayType()) {
3094 // Decay functions and arrays.
3095 Expr *RefE = (Expr *)RefExpr.get();
3096 DefaultFunctionArrayConversion(RefE);
3097 if (RefE != RefExpr.get()) {
3099 RefExpr = Owned(RefE);
3102 return move(RefExpr);
3105 // Take the address of everything else
3106 return CreateBuiltinUnaryOp(Loc, UnaryOperator::AddrOf, move(RefExpr));
3109 // If the non-type template parameter has reference type, qualify the
3110 // resulting declaration reference with the extra qualifiers on the
3111 // type that the reference refers to.
3112 if (const ReferenceType *TargetRef = ParamType->getAs<ReferenceType>())
3113 T = Context.getQualifiedType(T, TargetRef->getPointeeType().getQualifiers());
3115 return BuildDeclRefExpr(VD, T, Loc);
3118 /// \brief Construct a new expression that refers to the given
3119 /// integral template argument with the given source-location
3122 /// This routine takes care of the mapping from an integral template
3123 /// argument (which may have any integral type) to the appropriate
3125 Sema::OwningExprResult
3126 Sema::BuildExpressionFromIntegralTemplateArgument(const TemplateArgument &Arg,
3127 SourceLocation Loc) {
3128 assert(Arg.getKind() == TemplateArgument::Integral &&
3129 "Operation is only value for integral template arguments");
3130 QualType T = Arg.getIntegralType();
3131 if (T->isCharType() || T->isWideCharType())
3132 return Owned(new (Context) CharacterLiteral(
3133 Arg.getAsIntegral()->getZExtValue(),
3134 T->isWideCharType(),
3137 if (T->isBooleanType())
3138 return Owned(new (Context) CXXBoolLiteralExpr(
3139 Arg.getAsIntegral()->getBoolValue(),
3143 return Owned(new (Context) IntegerLiteral(*Arg.getAsIntegral(), T, Loc));
3147 /// \brief Determine whether the given template parameter lists are
3150 /// \param New The new template parameter list, typically written in the
3151 /// source code as part of a new template declaration.
3153 /// \param Old The old template parameter list, typically found via
3154 /// name lookup of the template declared with this template parameter
3157 /// \param Complain If true, this routine will produce a diagnostic if
3158 /// the template parameter lists are not equivalent.
3160 /// \param Kind describes how we are to match the template parameter lists.
3162 /// \param TemplateArgLoc If this source location is valid, then we
3163 /// are actually checking the template parameter list of a template
3164 /// argument (New) against the template parameter list of its
3165 /// corresponding template template parameter (Old). We produce
3166 /// slightly different diagnostics in this scenario.
3168 /// \returns True if the template parameter lists are equal, false
3171 Sema::TemplateParameterListsAreEqual(TemplateParameterList *New,
3172 TemplateParameterList *Old,
3174 TemplateParameterListEqualKind Kind,
3175 SourceLocation TemplateArgLoc) {
3176 if (Old->size() != New->size()) {
3178 unsigned NextDiag = diag::err_template_param_list_different_arity;
3179 if (TemplateArgLoc.isValid()) {
3180 Diag(TemplateArgLoc, diag::err_template_arg_template_params_mismatch);
3181 NextDiag = diag::note_template_param_list_different_arity;
3183 Diag(New->getTemplateLoc(), NextDiag)
3184 << (New->size() > Old->size())
3185 << (Kind != TPL_TemplateMatch)
3186 << SourceRange(New->getTemplateLoc(), New->getRAngleLoc());
3187 Diag(Old->getTemplateLoc(), diag::note_template_prev_declaration)
3188 << (Kind != TPL_TemplateMatch)
3189 << SourceRange(Old->getTemplateLoc(), Old->getRAngleLoc());
3195 for (TemplateParameterList::iterator OldParm = Old->begin(),
3196 OldParmEnd = Old->end(), NewParm = New->begin();
3197 OldParm != OldParmEnd; ++OldParm, ++NewParm) {
3198 if ((*OldParm)->getKind() != (*NewParm)->getKind()) {
3200 unsigned NextDiag = diag::err_template_param_different_kind;
3201 if (TemplateArgLoc.isValid()) {
3202 Diag(TemplateArgLoc, diag::err_template_arg_template_params_mismatch);
3203 NextDiag = diag::note_template_param_different_kind;
3205 Diag((*NewParm)->getLocation(), NextDiag)
3206 << (Kind != TPL_TemplateMatch);
3207 Diag((*OldParm)->getLocation(), diag::note_template_prev_declaration)
3208 << (Kind != TPL_TemplateMatch);
3213 if (TemplateTypeParmDecl *OldTTP
3214 = dyn_cast<TemplateTypeParmDecl>(*OldParm)) {
3215 // Template type parameters are equivalent if either both are template
3216 // type parameter packs or neither are (since we know we're at the same
3218 TemplateTypeParmDecl *NewTTP = cast<TemplateTypeParmDecl>(*NewParm);
3219 if (OldTTP->isParameterPack() != NewTTP->isParameterPack()) {
3220 // FIXME: Implement the rules in C++0x [temp.arg.template]p5 that
3221 // allow one to match a template parameter pack in the template
3222 // parameter list of a template template parameter to one or more
3223 // template parameters in the template parameter list of the
3224 // corresponding template template argument.
3226 unsigned NextDiag = diag::err_template_parameter_pack_non_pack;
3227 if (TemplateArgLoc.isValid()) {
3228 Diag(TemplateArgLoc,
3229 diag::err_template_arg_template_params_mismatch);
3230 NextDiag = diag::note_template_parameter_pack_non_pack;
3232 Diag(NewTTP->getLocation(), NextDiag)
3233 << 0 << NewTTP->isParameterPack();
3234 Diag(OldTTP->getLocation(), diag::note_template_parameter_pack_here)
3235 << 0 << OldTTP->isParameterPack();
3239 } else if (NonTypeTemplateParmDecl *OldNTTP
3240 = dyn_cast<NonTypeTemplateParmDecl>(*OldParm)) {
3241 // The types of non-type template parameters must agree.
3242 NonTypeTemplateParmDecl *NewNTTP
3243 = cast<NonTypeTemplateParmDecl>(*NewParm);
3245 // If we are matching a template template argument to a template
3246 // template parameter and one of the non-type template parameter types
3247 // is dependent, then we must wait until template instantiation time
3248 // to actually compare the arguments.
3249 if (Kind == TPL_TemplateTemplateArgumentMatch &&
3250 (OldNTTP->getType()->isDependentType() ||
3251 NewNTTP->getType()->isDependentType()))
3254 if (Context.getCanonicalType(OldNTTP->getType()) !=
3255 Context.getCanonicalType(NewNTTP->getType())) {
3257 unsigned NextDiag = diag::err_template_nontype_parm_different_type;
3258 if (TemplateArgLoc.isValid()) {
3259 Diag(TemplateArgLoc,
3260 diag::err_template_arg_template_params_mismatch);
3261 NextDiag = diag::note_template_nontype_parm_different_type;
3263 Diag(NewNTTP->getLocation(), NextDiag)
3264 << NewNTTP->getType()
3265 << (Kind != TPL_TemplateMatch);
3266 Diag(OldNTTP->getLocation(),
3267 diag::note_template_nontype_parm_prev_declaration)
3268 << OldNTTP->getType();
3273 // The template parameter lists of template template
3274 // parameters must agree.
3275 assert(isa<TemplateTemplateParmDecl>(*OldParm) &&
3276 "Only template template parameters handled here");
3277 TemplateTemplateParmDecl *OldTTP
3278 = cast<TemplateTemplateParmDecl>(*OldParm);
3279 TemplateTemplateParmDecl *NewTTP
3280 = cast<TemplateTemplateParmDecl>(*NewParm);
3281 if (!TemplateParameterListsAreEqual(NewTTP->getTemplateParameters(),
3282 OldTTP->getTemplateParameters(),
3284 (Kind == TPL_TemplateMatch? TPL_TemplateTemplateParmMatch : Kind),
3293 /// \brief Check whether a template can be declared within this scope.
3295 /// If the template declaration is valid in this scope, returns
3296 /// false. Otherwise, issues a diagnostic and returns true.
3298 Sema::CheckTemplateDeclScope(Scope *S, TemplateParameterList *TemplateParams) {
3299 // Find the nearest enclosing declaration scope.
3300 while ((S->getFlags() & Scope::DeclScope) == 0 ||
3301 (S->getFlags() & Scope::TemplateParamScope) != 0)
3305 // A template-declaration can appear only as a namespace scope or
3306 // class scope declaration.
3307 DeclContext *Ctx = static_cast<DeclContext *>(S->getEntity());
3308 if (Ctx && isa<LinkageSpecDecl>(Ctx) &&
3309 cast<LinkageSpecDecl>(Ctx)->getLanguage() != LinkageSpecDecl::lang_cxx)
3310 return Diag(TemplateParams->getTemplateLoc(), diag::err_template_linkage)
3311 << TemplateParams->getSourceRange();
3313 while (Ctx && isa<LinkageSpecDecl>(Ctx))
3314 Ctx = Ctx->getParent();
3316 if (Ctx && (Ctx->isFileContext() || Ctx->isRecord()))
3319 return Diag(TemplateParams->getTemplateLoc(),
3320 diag::err_template_outside_namespace_or_class_scope)
3321 << TemplateParams->getSourceRange();
3324 /// \brief Determine what kind of template specialization the given declaration
3326 static TemplateSpecializationKind getTemplateSpecializationKind(NamedDecl *D) {
3328 return TSK_Undeclared;
3330 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(D))
3331 return Record->getTemplateSpecializationKind();
3332 if (FunctionDecl *Function = dyn_cast<FunctionDecl>(D))
3333 return Function->getTemplateSpecializationKind();
3334 if (VarDecl *Var = dyn_cast<VarDecl>(D))
3335 return Var->getTemplateSpecializationKind();
3337 return TSK_Undeclared;
3340 /// \brief Check whether a specialization is well-formed in the current
3343 /// This routine determines whether a template specialization can be declared
3344 /// in the current context (C++ [temp.expl.spec]p2).
3346 /// \param S the semantic analysis object for which this check is being
3349 /// \param Specialized the entity being specialized or instantiated, which
3350 /// may be a kind of template (class template, function template, etc.) or
3351 /// a member of a class template (member function, static data member,
3354 /// \param PrevDecl the previous declaration of this entity, if any.
3356 /// \param Loc the location of the explicit specialization or instantiation of
3359 /// \param IsPartialSpecialization whether this is a partial specialization of
3360 /// a class template.
3362 /// \returns true if there was an error that we cannot recover from, false
3364 static bool CheckTemplateSpecializationScope(Sema &S,
3365 NamedDecl *Specialized,
3366 NamedDecl *PrevDecl,
3368 bool IsPartialSpecialization) {
3369 // Keep these "kind" numbers in sync with the %select statements in the
3370 // various diagnostics emitted by this routine.
3372 bool isTemplateSpecialization = false;
3373 if (isa<ClassTemplateDecl>(Specialized)) {
3374 EntityKind = IsPartialSpecialization? 1 : 0;
3375 isTemplateSpecialization = true;
3376 } else if (isa<FunctionTemplateDecl>(Specialized)) {
3378 isTemplateSpecialization = true;
3379 } else if (isa<CXXMethodDecl>(Specialized))
3381 else if (isa<VarDecl>(Specialized))
3383 else if (isa<RecordDecl>(Specialized))
3386 S.Diag(Loc, diag::err_template_spec_unknown_kind);
3387 S.Diag(Specialized->getLocation(), diag::note_specialized_entity);
3391 // C++ [temp.expl.spec]p2:
3392 // An explicit specialization shall be declared in the namespace
3393 // of which the template is a member, or, for member templates, in
3394 // the namespace of which the enclosing class or enclosing class
3395 // template is a member. An explicit specialization of a member
3396 // function, member class or static data member of a class
3397 // template shall be declared in the namespace of which the class
3398 // template is a member. Such a declaration may also be a
3399 // definition. If the declaration is not a definition, the
3400 // specialization may be defined later in the name- space in which
3401 // the explicit specialization was declared, or in a namespace
3402 // that encloses the one in which the explicit specialization was
3404 if (S.CurContext->getLookupContext()->isFunctionOrMethod()) {
3405 S.Diag(Loc, diag::err_template_spec_decl_function_scope)
3410 if (S.CurContext->isRecord() && !IsPartialSpecialization) {
3411 S.Diag(Loc, diag::err_template_spec_decl_class_scope)
3416 // C++ [temp.class.spec]p6:
3417 // A class template partial specialization may be declared or redeclared
3418 // in any namespace scope in which its definition may be defined (14.5.1
3420 bool ComplainedAboutScope = false;
3421 DeclContext *SpecializedContext
3422 = Specialized->getDeclContext()->getEnclosingNamespaceContext();
3423 DeclContext *DC = S.CurContext->getEnclosingNamespaceContext();
3425 getTemplateSpecializationKind(PrevDecl) == TSK_Undeclared ||
3426 getTemplateSpecializationKind(PrevDecl) == TSK_ImplicitInstantiation)){
3427 // There is no prior declaration of this entity, so this
3428 // specialization must be in the same context as the template
3430 if (!DC->Equals(SpecializedContext)) {
3431 if (isa<TranslationUnitDecl>(SpecializedContext))
3432 S.Diag(Loc, diag::err_template_spec_decl_out_of_scope_global)
3433 << EntityKind << Specialized;
3434 else if (isa<NamespaceDecl>(SpecializedContext))
3435 S.Diag(Loc, diag::err_template_spec_decl_out_of_scope)
3436 << EntityKind << Specialized
3437 << cast<NamedDecl>(SpecializedContext);
3439 S.Diag(Specialized->getLocation(), diag::note_specialized_entity);
3440 ComplainedAboutScope = true;
3444 // Make sure that this redeclaration (or definition) occurs in an enclosing
3446 // Note that HandleDeclarator() performs this check for explicit
3447 // specializations of function templates, static data members, and member
3448 // functions, so we skip the check here for those kinds of entities.
3449 // FIXME: HandleDeclarator's diagnostics aren't quite as good, though.
3450 // Should we refactor that check, so that it occurs later?
3451 if (!ComplainedAboutScope && !DC->Encloses(SpecializedContext) &&
3452 !(isa<FunctionTemplateDecl>(Specialized) || isa<VarDecl>(Specialized) ||
3453 isa<FunctionDecl>(Specialized))) {
3454 if (isa<TranslationUnitDecl>(SpecializedContext))
3455 S.Diag(Loc, diag::err_template_spec_redecl_global_scope)
3456 << EntityKind << Specialized;
3457 else if (isa<NamespaceDecl>(SpecializedContext))
3458 S.Diag(Loc, diag::err_template_spec_redecl_out_of_scope)
3459 << EntityKind << Specialized
3460 << cast<NamedDecl>(SpecializedContext);
3462 S.Diag(Specialized->getLocation(), diag::note_specialized_entity);
3465 // FIXME: check for specialization-after-instantiation errors and such.
3470 /// \brief Check the non-type template arguments of a class template
3471 /// partial specialization according to C++ [temp.class.spec]p9.
3473 /// \param TemplateParams the template parameters of the primary class
3476 /// \param TemplateArg the template arguments of the class template
3477 /// partial specialization.
3479 /// \param MirrorsPrimaryTemplate will be set true if the class
3480 /// template partial specialization arguments are identical to the
3481 /// implicit template arguments of the primary template. This is not
3482 /// necessarily an error (C++0x), and it is left to the caller to diagnose
3483 /// this condition when it is an error.
3485 /// \returns true if there was an error, false otherwise.
3486 bool Sema::CheckClassTemplatePartialSpecializationArgs(
3487 TemplateParameterList *TemplateParams,
3488 const TemplateArgumentListBuilder &TemplateArgs,
3489 bool &MirrorsPrimaryTemplate) {
3490 // FIXME: the interface to this function will have to change to
3491 // accommodate variadic templates.
3492 MirrorsPrimaryTemplate = true;
3494 const TemplateArgument *ArgList = TemplateArgs.getFlatArguments();
3496 for (unsigned I = 0, N = TemplateParams->size(); I != N; ++I) {
3497 // Determine whether the template argument list of the partial
3498 // specialization is identical to the implicit argument list of
3499 // the primary template. The caller may need to diagnostic this as
3500 // an error per C++ [temp.class.spec]p9b3.
3501 if (MirrorsPrimaryTemplate) {
3502 if (TemplateTypeParmDecl *TTP
3503 = dyn_cast<TemplateTypeParmDecl>(TemplateParams->getParam(I))) {
3504 if (Context.getCanonicalType(Context.getTypeDeclType(TTP)) !=
3505 Context.getCanonicalType(ArgList[I].getAsType()))
3506 MirrorsPrimaryTemplate = false;
3507 } else if (TemplateTemplateParmDecl *TTP
3508 = dyn_cast<TemplateTemplateParmDecl>(
3509 TemplateParams->getParam(I))) {
3510 TemplateName Name = ArgList[I].getAsTemplate();
3511 TemplateTemplateParmDecl *ArgDecl
3512 = dyn_cast_or_null<TemplateTemplateParmDecl>(Name.getAsTemplateDecl());
3514 ArgDecl->getIndex() != TTP->getIndex() ||
3515 ArgDecl->getDepth() != TTP->getDepth())
3516 MirrorsPrimaryTemplate = false;
3520 NonTypeTemplateParmDecl *Param
3521 = dyn_cast<NonTypeTemplateParmDecl>(TemplateParams->getParam(I));
3526 Expr *ArgExpr = ArgList[I].getAsExpr();
3528 MirrorsPrimaryTemplate = false;
3532 // C++ [temp.class.spec]p8:
3533 // A non-type argument is non-specialized if it is the name of a
3534 // non-type parameter. All other non-type arguments are
3537 // Below, we check the two conditions that only apply to
3538 // specialized non-type arguments, so skip any non-specialized
3540 if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(ArgExpr))
3541 if (NonTypeTemplateParmDecl *NTTP
3542 = dyn_cast<NonTypeTemplateParmDecl>(DRE->getDecl())) {
3543 if (MirrorsPrimaryTemplate &&
3544 (Param->getIndex() != NTTP->getIndex() ||
3545 Param->getDepth() != NTTP->getDepth()))
3546 MirrorsPrimaryTemplate = false;
3551 // C++ [temp.class.spec]p9:
3552 // Within the argument list of a class template partial
3553 // specialization, the following restrictions apply:
3554 // -- A partially specialized non-type argument expression
3555 // shall not involve a template parameter of the partial
3556 // specialization except when the argument expression is a
3557 // simple identifier.
3558 if (ArgExpr->isTypeDependent() || ArgExpr->isValueDependent()) {
3559 Diag(ArgExpr->getLocStart(),
3560 diag::err_dependent_non_type_arg_in_partial_spec)
3561 << ArgExpr->getSourceRange();
3565 // -- The type of a template parameter corresponding to a
3566 // specialized non-type argument shall not be dependent on a
3567 // parameter of the specialization.
3568 if (Param->getType()->isDependentType()) {
3569 Diag(ArgExpr->getLocStart(),
3570 diag::err_dependent_typed_non_type_arg_in_partial_spec)
3572 << ArgExpr->getSourceRange();
3573 Diag(Param->getLocation(), diag::note_template_param_here);
3577 MirrorsPrimaryTemplate = false;
3583 /// \brief Retrieve the previous declaration of the given declaration.
3584 static NamedDecl *getPreviousDecl(NamedDecl *ND) {
3585 if (VarDecl *VD = dyn_cast<VarDecl>(ND))
3586 return VD->getPreviousDeclaration();
3587 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(ND))
3588 return FD->getPreviousDeclaration();
3589 if (TagDecl *TD = dyn_cast<TagDecl>(ND))
3590 return TD->getPreviousDeclaration();
3591 if (TypedefDecl *TD = dyn_cast<TypedefDecl>(ND))
3592 return TD->getPreviousDeclaration();
3593 if (FunctionTemplateDecl *FTD = dyn_cast<FunctionTemplateDecl>(ND))
3594 return FTD->getPreviousDeclaration();
3595 if (ClassTemplateDecl *CTD = dyn_cast<ClassTemplateDecl>(ND))
3596 return CTD->getPreviousDeclaration();
3601 Sema::ActOnClassTemplateSpecialization(Scope *S, unsigned TagSpec,
3603 SourceLocation KWLoc,
3605 TemplateTy TemplateD,
3606 SourceLocation TemplateNameLoc,
3607 SourceLocation LAngleLoc,
3608 ASTTemplateArgsPtr TemplateArgsIn,
3609 SourceLocation RAngleLoc,
3610 AttributeList *Attr,
3611 MultiTemplateParamsArg TemplateParameterLists) {
3612 assert(TUK != TUK_Reference && "References are not specializations");
3614 // Find the class template we're specializing
3615 TemplateName Name = TemplateD.getAsVal<TemplateName>();
3616 ClassTemplateDecl *ClassTemplate
3617 = dyn_cast_or_null<ClassTemplateDecl>(Name.getAsTemplateDecl());
3619 if (!ClassTemplate) {
3620 Diag(TemplateNameLoc, diag::err_not_class_template_specialization)
3621 << (Name.getAsTemplateDecl() &&
3622 isa<TemplateTemplateParmDecl>(Name.getAsTemplateDecl()));
3626 bool isExplicitSpecialization = false;
3627 bool isPartialSpecialization = false;
3629 // Check the validity of the template headers that introduce this
3631 // FIXME: We probably shouldn't complain about these headers for
3632 // friend declarations.
3633 bool Invalid = false;
3634 TemplateParameterList *TemplateParams
3635 = MatchTemplateParametersToScopeSpecifier(TemplateNameLoc, SS,
3636 (TemplateParameterList**)TemplateParameterLists.get(),
3637 TemplateParameterLists.size(),
3639 isExplicitSpecialization,
3644 unsigned NumMatchedTemplateParamLists = TemplateParameterLists.size();
3646 --NumMatchedTemplateParamLists;
3648 if (TemplateParams && TemplateParams->size() > 0) {
3649 isPartialSpecialization = true;
3651 // C++ [temp.class.spec]p10:
3652 // The template parameter list of a specialization shall not
3653 // contain default template argument values.
3654 for (unsigned I = 0, N = TemplateParams->size(); I != N; ++I) {
3655 Decl *Param = TemplateParams->getParam(I);
3656 if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(Param)) {
3657 if (TTP->hasDefaultArgument()) {
3658 Diag(TTP->getDefaultArgumentLoc(),
3659 diag::err_default_arg_in_partial_spec);
3660 TTP->removeDefaultArgument();
3662 } else if (NonTypeTemplateParmDecl *NTTP
3663 = dyn_cast<NonTypeTemplateParmDecl>(Param)) {
3664 if (Expr *DefArg = NTTP->getDefaultArgument()) {
3665 Diag(NTTP->getDefaultArgumentLoc(),
3666 diag::err_default_arg_in_partial_spec)
3667 << DefArg->getSourceRange();
3668 NTTP->removeDefaultArgument();
3669 DefArg->Destroy(Context);
3672 TemplateTemplateParmDecl *TTP = cast<TemplateTemplateParmDecl>(Param);
3673 if (TTP->hasDefaultArgument()) {
3674 Diag(TTP->getDefaultArgument().getLocation(),
3675 diag::err_default_arg_in_partial_spec)
3676 << TTP->getDefaultArgument().getSourceRange();
3677 TTP->removeDefaultArgument();
3681 } else if (TemplateParams) {
3682 if (TUK == TUK_Friend)
3683 Diag(KWLoc, diag::err_template_spec_friend)
3684 << FixItHint::CreateRemoval(
3685 SourceRange(TemplateParams->getTemplateLoc(),
3686 TemplateParams->getRAngleLoc()))
3687 << SourceRange(LAngleLoc, RAngleLoc);
3689 isExplicitSpecialization = true;
3690 } else if (TUK != TUK_Friend) {
3691 Diag(KWLoc, diag::err_template_spec_needs_header)
3692 << FixItHint::CreateInsertion(KWLoc, "template<> ");
3693 isExplicitSpecialization = true;
3696 // Check that the specialization uses the same tag kind as the
3697 // original template.
3698 TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec);
3699 assert(Kind != TTK_Enum && "Invalid enum tag in class template spec!");
3700 if (!isAcceptableTagRedeclaration(ClassTemplate->getTemplatedDecl(),
3702 *ClassTemplate->getIdentifier())) {
3703 Diag(KWLoc, diag::err_use_with_wrong_tag)
3705 << FixItHint::CreateReplacement(KWLoc,
3706 ClassTemplate->getTemplatedDecl()->getKindName());
3707 Diag(ClassTemplate->getTemplatedDecl()->getLocation(),
3708 diag::note_previous_use);
3709 Kind = ClassTemplate->getTemplatedDecl()->getTagKind();
3712 // Translate the parser's template argument list in our AST format.
3713 TemplateArgumentListInfo TemplateArgs;
3714 TemplateArgs.setLAngleLoc(LAngleLoc);
3715 TemplateArgs.setRAngleLoc(RAngleLoc);
3716 translateTemplateArguments(TemplateArgsIn, TemplateArgs);
3718 // Check that the template argument list is well-formed for this
3720 TemplateArgumentListBuilder Converted(ClassTemplate->getTemplateParameters(),
3721 TemplateArgs.size());
3722 if (CheckTemplateArgumentList(ClassTemplate, TemplateNameLoc,
3723 TemplateArgs, false, Converted))
3726 assert((Converted.structuredSize() ==
3727 ClassTemplate->getTemplateParameters()->size()) &&
3728 "Converted template argument list is too short!");
3730 // Find the class template (partial) specialization declaration that
3731 // corresponds to these arguments.
3732 llvm::FoldingSetNodeID ID;
3733 if (isPartialSpecialization) {
3734 bool MirrorsPrimaryTemplate;
3735 if (CheckClassTemplatePartialSpecializationArgs(
3736 ClassTemplate->getTemplateParameters(),
3737 Converted, MirrorsPrimaryTemplate))
3740 if (MirrorsPrimaryTemplate) {
3741 // C++ [temp.class.spec]p9b3:
3743 // -- The argument list of the specialization shall not be identical
3744 // to the implicit argument list of the primary template.
3745 Diag(TemplateNameLoc, diag::err_partial_spec_args_match_primary_template)
3746 << (TUK == TUK_Definition)
3747 << FixItHint::CreateRemoval(SourceRange(LAngleLoc, RAngleLoc));
3748 return CheckClassTemplate(S, TagSpec, TUK, KWLoc, SS,
3749 ClassTemplate->getIdentifier(),
3756 // FIXME: Diagnose friend partial specializations
3758 if (!Name.isDependent() &&
3759 !TemplateSpecializationType::anyDependentTemplateArguments(
3760 TemplateArgs.getArgumentArray(),
3761 TemplateArgs.size())) {
3762 Diag(TemplateNameLoc, diag::err_partial_spec_fully_specialized)
3763 << ClassTemplate->getDeclName();
3764 isPartialSpecialization = false;
3766 // FIXME: Template parameter list matters, too
3767 ClassTemplatePartialSpecializationDecl::Profile(ID,
3768 Converted.getFlatArguments(),
3769 Converted.flatSize(),
3774 if (!isPartialSpecialization)
3775 ClassTemplateSpecializationDecl::Profile(ID,
3776 Converted.getFlatArguments(),
3777 Converted.flatSize(),
3779 void *InsertPos = 0;
3780 ClassTemplateSpecializationDecl *PrevDecl = 0;
3782 if (isPartialSpecialization)
3784 = ClassTemplate->getPartialSpecializations().FindNodeOrInsertPos(ID,
3788 = ClassTemplate->getSpecializations().FindNodeOrInsertPos(ID, InsertPos);
3790 ClassTemplateSpecializationDecl *Specialization = 0;
3792 // Check whether we can declare a class template specialization in
3793 // the current scope.
3794 if (TUK != TUK_Friend &&
3795 CheckTemplateSpecializationScope(*this, ClassTemplate, PrevDecl,
3797 isPartialSpecialization))
3800 // The canonical type
3803 (PrevDecl->getSpecializationKind() == TSK_Undeclared ||
3804 TUK == TUK_Friend)) {
3805 // Since the only prior class template specialization with these
3806 // arguments was referenced but not declared, or we're only
3807 // referencing this specialization as a friend, reuse that
3808 // declaration node as our own, updating its source location to
3809 // reflect our new declaration.
3810 Specialization = PrevDecl;
3811 Specialization->setLocation(TemplateNameLoc);
3813 CanonType = Context.getTypeDeclType(Specialization);
3814 } else if (isPartialSpecialization) {
3815 // Build the canonical type that describes the converted template
3816 // arguments of the class template partial specialization.
3817 TemplateName CanonTemplate = Context.getCanonicalTemplateName(Name);
3818 CanonType = Context.getTemplateSpecializationType(CanonTemplate,
3819 Converted.getFlatArguments(),
3820 Converted.flatSize());
3822 // Create a new class template partial specialization declaration node.
3823 ClassTemplatePartialSpecializationDecl *PrevPartial
3824 = cast_or_null<ClassTemplatePartialSpecializationDecl>(PrevDecl);
3825 unsigned SequenceNumber = PrevPartial? PrevPartial->getSequenceNumber()
3826 : ClassTemplate->getPartialSpecializations().size();
3827 ClassTemplatePartialSpecializationDecl *Partial
3828 = ClassTemplatePartialSpecializationDecl::Create(Context, Kind,
3829 ClassTemplate->getDeclContext(),
3838 SetNestedNameSpecifier(Partial, SS);
3839 if (NumMatchedTemplateParamLists > 0) {
3840 Partial->setTemplateParameterListsInfo(Context,
3841 NumMatchedTemplateParamLists,
3842 (TemplateParameterList**) TemplateParameterLists.release());
3846 ClassTemplate->getPartialSpecializations().RemoveNode(PrevPartial);
3847 ClassTemplate->getPartialSpecializations().GetOrInsertNode(Partial);
3849 ClassTemplate->getPartialSpecializations().InsertNode(Partial, InsertPos);
3851 Specialization = Partial;
3853 // If we are providing an explicit specialization of a member class
3854 // template specialization, make a note of that.
3855 if (PrevPartial && PrevPartial->getInstantiatedFromMember())
3856 PrevPartial->setMemberSpecialization();
3858 // Check that all of the template parameters of the class template
3859 // partial specialization are deducible from the template
3860 // arguments. If not, this class template partial specialization
3861 // will never be used.
3862 llvm::SmallVector<bool, 8> DeducibleParams;
3863 DeducibleParams.resize(TemplateParams->size());
3864 MarkUsedTemplateParameters(Partial->getTemplateArgs(), true,
3865 TemplateParams->getDepth(),
3867 unsigned NumNonDeducible = 0;
3868 for (unsigned I = 0, N = DeducibleParams.size(); I != N; ++I)
3869 if (!DeducibleParams[I])
3872 if (NumNonDeducible) {
3873 Diag(TemplateNameLoc, diag::warn_partial_specs_not_deducible)
3874 << (NumNonDeducible > 1)
3875 << SourceRange(TemplateNameLoc, RAngleLoc);
3876 for (unsigned I = 0, N = DeducibleParams.size(); I != N; ++I) {
3877 if (!DeducibleParams[I]) {
3878 NamedDecl *Param = cast<NamedDecl>(TemplateParams->getParam(I));
3879 if (Param->getDeclName())
3880 Diag(Param->getLocation(),
3881 diag::note_partial_spec_unused_parameter)
3882 << Param->getDeclName();
3884 Diag(Param->getLocation(),
3885 diag::note_partial_spec_unused_parameter)
3886 << std::string("<anonymous>");
3891 // Create a new class template specialization declaration node for
3892 // this explicit specialization or friend declaration.
3894 = ClassTemplateSpecializationDecl::Create(Context, Kind,
3895 ClassTemplate->getDeclContext(),
3900 SetNestedNameSpecifier(Specialization, SS);
3901 if (NumMatchedTemplateParamLists > 0) {
3902 Specialization->setTemplateParameterListsInfo(Context,
3903 NumMatchedTemplateParamLists,
3904 (TemplateParameterList**) TemplateParameterLists.release());
3908 ClassTemplate->getSpecializations().RemoveNode(PrevDecl);
3909 ClassTemplate->getSpecializations().GetOrInsertNode(Specialization);
3911 ClassTemplate->getSpecializations().InsertNode(Specialization,
3915 CanonType = Context.getTypeDeclType(Specialization);
3918 // C++ [temp.expl.spec]p6:
3919 // If a template, a member template or the member of a class template is
3920 // explicitly specialized then that specialization shall be declared
3921 // before the first use of that specialization that would cause an implicit
3922 // instantiation to take place, in every translation unit in which such a
3923 // use occurs; no diagnostic is required.
3924 if (PrevDecl && PrevDecl->getPointOfInstantiation().isValid()) {
3926 for (NamedDecl *Prev = PrevDecl; Prev; Prev = getPreviousDecl(Prev)) {
3927 // Is there any previous explicit specialization declaration?
3928 if (getTemplateSpecializationKind(Prev) == TSK_ExplicitSpecialization) {
3935 SourceRange Range(TemplateNameLoc, RAngleLoc);
3936 Diag(TemplateNameLoc, diag::err_specialization_after_instantiation)
3937 << Context.getTypeDeclType(Specialization) << Range;
3939 Diag(PrevDecl->getPointOfInstantiation(),
3940 diag::note_instantiation_required_here)
3941 << (PrevDecl->getTemplateSpecializationKind()
3942 != TSK_ImplicitInstantiation);
3947 // If this is not a friend, note that this is an explicit specialization.
3948 if (TUK != TUK_Friend)
3949 Specialization->setSpecializationKind(TSK_ExplicitSpecialization);
3951 // Check that this isn't a redefinition of this specialization.
3952 if (TUK == TUK_Definition) {
3953 if (RecordDecl *Def = Specialization->getDefinition()) {
3954 SourceRange Range(TemplateNameLoc, RAngleLoc);
3955 Diag(TemplateNameLoc, diag::err_redefinition)
3956 << Context.getTypeDeclType(Specialization) << Range;
3957 Diag(Def->getLocation(), diag::note_previous_definition);
3958 Specialization->setInvalidDecl();
3963 // Build the fully-sugared type for this class template
3964 // specialization as the user wrote in the specialization
3965 // itself. This means that we'll pretty-print the type retrieved
3966 // from the specialization's declaration the way that the user
3967 // actually wrote the specialization, rather than formatting the
3968 // name based on the "canonical" representation used to store the
3969 // template arguments in the specialization.
3970 TypeSourceInfo *WrittenTy
3971 = Context.getTemplateSpecializationTypeInfo(Name, TemplateNameLoc,
3972 TemplateArgs, CanonType);
3973 if (TUK != TUK_Friend) {
3974 Specialization->setTypeAsWritten(WrittenTy);
3976 Specialization->setTemplateKeywordLoc(TemplateParams->getTemplateLoc());
3978 TemplateArgsIn.release();
3980 // C++ [temp.expl.spec]p9:
3981 // A template explicit specialization is in the scope of the
3982 // namespace in which the template was defined.
3984 // We actually implement this paragraph where we set the semantic
3985 // context (in the creation of the ClassTemplateSpecializationDecl),
3986 // but we also maintain the lexical context where the actual
3987 // definition occurs.
3988 Specialization->setLexicalDeclContext(CurContext);
3990 // We may be starting the definition of this specialization.
3991 if (TUK == TUK_Definition)
3992 Specialization->startDefinition();
3994 if (TUK == TUK_Friend) {
3995 FriendDecl *Friend = FriendDecl::Create(Context, CurContext,
3999 Friend->setAccess(AS_public);
4000 CurContext->addDecl(Friend);
4002 // Add the specialization into its lexical context, so that it can
4003 // be seen when iterating through the list of declarations in that
4004 // context. However, specializations are not found by name lookup.
4005 CurContext->addDecl(Specialization);
4007 return DeclPtrTy::make(Specialization);
4011 Sema::ActOnTemplateDeclarator(Scope *S,
4012 MultiTemplateParamsArg TemplateParameterLists,
4014 return HandleDeclarator(S, D, move(TemplateParameterLists), false);
4018 Sema::ActOnStartOfFunctionTemplateDef(Scope *FnBodyScope,
4019 MultiTemplateParamsArg TemplateParameterLists,
4021 assert(getCurFunctionDecl() == 0 && "Function parsing confused");
4022 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function &&
4023 "Not a function declarator!");
4024 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun;
4026 if (FTI.hasPrototype) {
4027 // FIXME: Diagnose arguments without names in C.
4030 Scope *ParentScope = FnBodyScope->getParent();
4032 DeclPtrTy DP = HandleDeclarator(ParentScope, D,
4033 move(TemplateParameterLists),
4034 /*IsFunctionDefinition=*/true);
4035 if (FunctionTemplateDecl *FunctionTemplate
4036 = dyn_cast_or_null<FunctionTemplateDecl>(DP.getAs<Decl>()))
4037 return ActOnStartOfFunctionDef(FnBodyScope,
4038 DeclPtrTy::make(FunctionTemplate->getTemplatedDecl()));
4039 if (FunctionDecl *Function = dyn_cast_or_null<FunctionDecl>(DP.getAs<Decl>()))
4040 return ActOnStartOfFunctionDef(FnBodyScope, DeclPtrTy::make(Function));
4044 /// \brief Strips various properties off an implicit instantiation
4045 /// that has just been explicitly specialized.
4046 static void StripImplicitInstantiation(NamedDecl *D) {
4047 D->invalidateAttrs();
4049 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
4050 FD->setInlineSpecified(false);
4054 /// \brief Diagnose cases where we have an explicit template specialization
4055 /// before/after an explicit template instantiation, producing diagnostics
4056 /// for those cases where they are required and determining whether the
4057 /// new specialization/instantiation will have any effect.
4059 /// \param NewLoc the location of the new explicit specialization or
4062 /// \param NewTSK the kind of the new explicit specialization or instantiation.
4064 /// \param PrevDecl the previous declaration of the entity.
4066 /// \param PrevTSK the kind of the old explicit specialization or instantiatin.
4068 /// \param PrevPointOfInstantiation if valid, indicates where the previus
4069 /// declaration was instantiated (either implicitly or explicitly).
4071 /// \param HasNoEffect will be set to true to indicate that the new
4072 /// specialization or instantiation has no effect and should be ignored.
4074 /// \returns true if there was an error that should prevent the introduction of
4075 /// the new declaration into the AST, false otherwise.
4077 Sema::CheckSpecializationInstantiationRedecl(SourceLocation NewLoc,
4078 TemplateSpecializationKind NewTSK,
4079 NamedDecl *PrevDecl,
4080 TemplateSpecializationKind PrevTSK,
4081 SourceLocation PrevPointOfInstantiation,
4082 bool &HasNoEffect) {
4083 HasNoEffect = false;
4086 case TSK_Undeclared:
4087 case TSK_ImplicitInstantiation:
4088 assert(false && "Don't check implicit instantiations here");
4091 case TSK_ExplicitSpecialization:
4093 case TSK_Undeclared:
4094 case TSK_ExplicitSpecialization:
4095 // Okay, we're just specializing something that is either already
4096 // explicitly specialized or has merely been mentioned without any
4100 case TSK_ImplicitInstantiation:
4101 if (PrevPointOfInstantiation.isInvalid()) {
4102 // The declaration itself has not actually been instantiated, so it is
4103 // still okay to specialize it.
4104 StripImplicitInstantiation(PrevDecl);
4109 case TSK_ExplicitInstantiationDeclaration:
4110 case TSK_ExplicitInstantiationDefinition:
4111 assert((PrevTSK == TSK_ImplicitInstantiation ||
4112 PrevPointOfInstantiation.isValid()) &&
4113 "Explicit instantiation without point of instantiation?");
4115 // C++ [temp.expl.spec]p6:
4116 // If a template, a member template or the member of a class template
4117 // is explicitly specialized then that specialization shall be declared
4118 // before the first use of that specialization that would cause an
4119 // implicit instantiation to take place, in every translation unit in
4120 // which such a use occurs; no diagnostic is required.
4121 for (NamedDecl *Prev = PrevDecl; Prev; Prev = getPreviousDecl(Prev)) {
4122 // Is there any previous explicit specialization declaration?
4123 if (getTemplateSpecializationKind(Prev) == TSK_ExplicitSpecialization)
4127 Diag(NewLoc, diag::err_specialization_after_instantiation)
4129 Diag(PrevPointOfInstantiation, diag::note_instantiation_required_here)
4130 << (PrevTSK != TSK_ImplicitInstantiation);
4136 case TSK_ExplicitInstantiationDeclaration:
4138 case TSK_ExplicitInstantiationDeclaration:
4139 // This explicit instantiation declaration is redundant (that's okay).
4143 case TSK_Undeclared:
4144 case TSK_ImplicitInstantiation:
4145 // We're explicitly instantiating something that may have already been
4146 // implicitly instantiated; that's fine.
4149 case TSK_ExplicitSpecialization:
4150 // C++0x [temp.explicit]p4:
4151 // For a given set of template parameters, if an explicit instantiation
4152 // of a template appears after a declaration of an explicit
4153 // specialization for that template, the explicit instantiation has no
4158 case TSK_ExplicitInstantiationDefinition:
4159 // C++0x [temp.explicit]p10:
4160 // If an entity is the subject of both an explicit instantiation
4161 // declaration and an explicit instantiation definition in the same
4162 // translation unit, the definition shall follow the declaration.
4164 diag::err_explicit_instantiation_declaration_after_definition);
4165 Diag(PrevPointOfInstantiation,
4166 diag::note_explicit_instantiation_definition_here);
4167 assert(PrevPointOfInstantiation.isValid() &&
4168 "Explicit instantiation without point of instantiation?");
4174 case TSK_ExplicitInstantiationDefinition:
4176 case TSK_Undeclared:
4177 case TSK_ImplicitInstantiation:
4178 // We're explicitly instantiating something that may have already been
4179 // implicitly instantiated; that's fine.
4182 case TSK_ExplicitSpecialization:
4183 // C++ DR 259, C++0x [temp.explicit]p4:
4184 // For a given set of template parameters, if an explicit
4185 // instantiation of a template appears after a declaration of
4186 // an explicit specialization for that template, the explicit
4187 // instantiation has no effect.
4189 // In C++98/03 mode, we only give an extension warning here, because it
4190 // is not harmful to try to explicitly instantiate something that
4191 // has been explicitly specialized.
4192 if (!getLangOptions().CPlusPlus0x) {
4193 Diag(NewLoc, diag::ext_explicit_instantiation_after_specialization)
4195 Diag(PrevDecl->getLocation(),
4196 diag::note_previous_template_specialization);
4201 case TSK_ExplicitInstantiationDeclaration:
4202 // We're explicity instantiating a definition for something for which we
4203 // were previously asked to suppress instantiations. That's fine.
4206 case TSK_ExplicitInstantiationDefinition:
4207 // C++0x [temp.spec]p5:
4208 // For a given template and a given set of template-arguments,
4209 // - an explicit instantiation definition shall appear at most once
4211 Diag(NewLoc, diag::err_explicit_instantiation_duplicate)
4213 Diag(PrevPointOfInstantiation,
4214 diag::note_previous_explicit_instantiation);
4221 assert(false && "Missing specialization/instantiation case?");
4226 /// \brief Perform semantic analysis for the given dependent function
4227 /// template specialization. The only possible way to get a dependent
4228 /// function template specialization is with a friend declaration,
4231 /// template <class T> void foo(T);
4232 /// template <class T> class A {
4233 /// friend void foo<>(T);
4236 /// There really isn't any useful analysis we can do here, so we
4237 /// just store the information.
4239 Sema::CheckDependentFunctionTemplateSpecialization(FunctionDecl *FD,
4240 const TemplateArgumentListInfo &ExplicitTemplateArgs,
4241 LookupResult &Previous) {
4242 // Remove anything from Previous that isn't a function template in
4243 // the correct context.
4244 DeclContext *FDLookupContext = FD->getDeclContext()->getLookupContext();
4245 LookupResult::Filter F = Previous.makeFilter();
4246 while (F.hasNext()) {
4247 NamedDecl *D = F.next()->getUnderlyingDecl();
4248 if (!isa<FunctionTemplateDecl>(D) ||
4249 !FDLookupContext->Equals(D->getDeclContext()->getLookupContext()))
4254 // Should this be diagnosed here?
4255 if (Previous.empty()) return true;
4257 FD->setDependentTemplateSpecialization(Context, Previous.asUnresolvedSet(),
4258 ExplicitTemplateArgs);
4262 /// \brief Perform semantic analysis for the given function template
4265 /// This routine performs all of the semantic analysis required for an
4266 /// explicit function template specialization. On successful completion,
4267 /// the function declaration \p FD will become a function template
4270 /// \param FD the function declaration, which will be updated to become a
4271 /// function template specialization.
4273 /// \param ExplicitTemplateArgs the explicitly-provided template arguments,
4274 /// if any. Note that this may be valid info even when 0 arguments are
4275 /// explicitly provided as in, e.g., \c void sort<>(char*, char*);
4276 /// as it anyway contains info on the angle brackets locations.
4278 /// \param PrevDecl the set of declarations that may be specialized by
4279 /// this function specialization.
4281 Sema::CheckFunctionTemplateSpecialization(FunctionDecl *FD,
4282 const TemplateArgumentListInfo *ExplicitTemplateArgs,
4283 LookupResult &Previous) {
4284 // The set of function template specializations that could match this
4285 // explicit function template specialization.
4286 UnresolvedSet<8> Candidates;
4288 DeclContext *FDLookupContext = FD->getDeclContext()->getLookupContext();
4289 for (LookupResult::iterator I = Previous.begin(), E = Previous.end();
4291 NamedDecl *Ovl = (*I)->getUnderlyingDecl();
4292 if (FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(Ovl)) {
4293 // Only consider templates found within the same semantic lookup scope as
4295 if (!FDLookupContext->Equals(Ovl->getDeclContext()->getLookupContext()))
4298 // C++ [temp.expl.spec]p11:
4299 // A trailing template-argument can be left unspecified in the
4300 // template-id naming an explicit function template specialization
4301 // provided it can be deduced from the function argument type.
4302 // Perform template argument deduction to determine whether we may be
4303 // specializing this template.
4304 // FIXME: It is somewhat wasteful to build
4305 TemplateDeductionInfo Info(Context, FD->getLocation());
4306 FunctionDecl *Specialization = 0;
4307 if (TemplateDeductionResult TDK
4308 = DeduceTemplateArguments(FunTmpl, ExplicitTemplateArgs,
4312 // FIXME: Template argument deduction failed; record why it failed, so
4313 // that we can provide nifty diagnostics.
4318 // Record this candidate.
4319 Candidates.addDecl(Specialization, I.getAccess());
4323 // Find the most specialized function template.
4324 UnresolvedSetIterator Result
4325 = getMostSpecialized(Candidates.begin(), Candidates.end(),
4326 TPOC_Other, FD->getLocation(),
4327 PDiag(diag::err_function_template_spec_no_match)
4328 << FD->getDeclName(),
4329 PDiag(diag::err_function_template_spec_ambiguous)
4330 << FD->getDeclName() << (ExplicitTemplateArgs != 0),
4331 PDiag(diag::note_function_template_spec_matched));
4332 if (Result == Candidates.end())
4335 // Ignore access information; it doesn't figure into redeclaration checking.
4336 FunctionDecl *Specialization = cast<FunctionDecl>(*Result);
4337 Specialization->setLocation(FD->getLocation());
4339 // FIXME: Check if the prior specialization has a point of instantiation.
4340 // If so, we have run afoul of .
4342 // If this is a friend declaration, then we're not really declaring
4343 // an explicit specialization.
4344 bool isFriend = (FD->getFriendObjectKind() != Decl::FOK_None);
4346 // Check the scope of this explicit specialization.
4348 CheckTemplateSpecializationScope(*this,
4349 Specialization->getPrimaryTemplate(),
4350 Specialization, FD->getLocation(),
4354 // C++ [temp.expl.spec]p6:
4355 // If a template, a member template or the member of a class template is
4356 // explicitly specialized then that specialization shall be declared
4357 // before the first use of that specialization that would cause an implicit
4358 // instantiation to take place, in every translation unit in which such a
4359 // use occurs; no diagnostic is required.
4360 FunctionTemplateSpecializationInfo *SpecInfo
4361 = Specialization->getTemplateSpecializationInfo();
4362 assert(SpecInfo && "Function template specialization info missing?");
4364 bool HasNoEffect = false;
4366 CheckSpecializationInstantiationRedecl(FD->getLocation(),
4367 TSK_ExplicitSpecialization,
4369 SpecInfo->getTemplateSpecializationKind(),
4370 SpecInfo->getPointOfInstantiation(),
4374 // Mark the prior declaration as an explicit specialization, so that later
4375 // clients know that this is an explicit specialization.
4377 SpecInfo->setTemplateSpecializationKind(TSK_ExplicitSpecialization);
4379 // Turn the given function declaration into a function template
4380 // specialization, with the template arguments from the previous
4382 // Take copies of (semantic and syntactic) template argument lists.
4383 const TemplateArgumentList* TemplArgs = new (Context)
4384 TemplateArgumentList(Specialization->getTemplateSpecializationArgs());
4385 const TemplateArgumentListInfo* TemplArgsAsWritten = ExplicitTemplateArgs
4386 ? new (Context) TemplateArgumentListInfo(*ExplicitTemplateArgs) : 0;
4387 FD->setFunctionTemplateSpecialization(Specialization->getPrimaryTemplate(),
4388 TemplArgs, /*InsertPos=*/0,
4389 SpecInfo->getTemplateSpecializationKind(),
4390 TemplArgsAsWritten);
4392 // The "previous declaration" for this function template specialization is
4393 // the prior function template specialization.
4395 Previous.addDecl(Specialization);
4399 /// \brief Perform semantic analysis for the given non-template member
4402 /// This routine performs all of the semantic analysis required for an
4403 /// explicit member function specialization. On successful completion,
4404 /// the function declaration \p FD will become a member function
4407 /// \param Member the member declaration, which will be updated to become a
4410 /// \param Previous the set of declarations, one of which may be specialized
4411 /// by this function specialization; the set will be modified to contain the
4412 /// redeclared member.
4414 Sema::CheckMemberSpecialization(NamedDecl *Member, LookupResult &Previous) {
4415 assert(!isa<TemplateDecl>(Member) && "Only for non-template members");
4417 // Try to find the member we are instantiating.
4418 NamedDecl *Instantiation = 0;
4419 NamedDecl *InstantiatedFrom = 0;
4420 MemberSpecializationInfo *MSInfo = 0;
4422 if (Previous.empty()) {
4423 // Nowhere to look anyway.
4424 } else if (FunctionDecl *Function = dyn_cast<FunctionDecl>(Member)) {
4425 for (LookupResult::iterator I = Previous.begin(), E = Previous.end();
4427 NamedDecl *D = (*I)->getUnderlyingDecl();
4428 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(D)) {
4429 if (Context.hasSameType(Function->getType(), Method->getType())) {
4430 Instantiation = Method;
4431 InstantiatedFrom = Method->getInstantiatedFromMemberFunction();
4432 MSInfo = Method->getMemberSpecializationInfo();
4437 } else if (isa<VarDecl>(Member)) {
4439 if (Previous.isSingleResult() &&
4440 (PrevVar = dyn_cast<VarDecl>(Previous.getFoundDecl())))
4441 if (PrevVar->isStaticDataMember()) {
4442 Instantiation = PrevVar;
4443 InstantiatedFrom = PrevVar->getInstantiatedFromStaticDataMember();
4444 MSInfo = PrevVar->getMemberSpecializationInfo();
4446 } else if (isa<RecordDecl>(Member)) {
4447 CXXRecordDecl *PrevRecord;
4448 if (Previous.isSingleResult() &&
4449 (PrevRecord = dyn_cast<CXXRecordDecl>(Previous.getFoundDecl()))) {
4450 Instantiation = PrevRecord;
4451 InstantiatedFrom = PrevRecord->getInstantiatedFromMemberClass();
4452 MSInfo = PrevRecord->getMemberSpecializationInfo();
4456 if (!Instantiation) {
4457 // There is no previous declaration that matches. Since member
4458 // specializations are always out-of-line, the caller will complain about
4459 // this mismatch later.
4463 // If this is a friend, just bail out here before we start turning
4464 // things into explicit specializations.
4465 if (Member->getFriendObjectKind() != Decl::FOK_None) {
4466 // Preserve instantiation information.
4467 if (InstantiatedFrom && isa<CXXMethodDecl>(Member)) {
4468 cast<CXXMethodDecl>(Member)->setInstantiationOfMemberFunction(
4469 cast<CXXMethodDecl>(InstantiatedFrom),
4470 cast<CXXMethodDecl>(Instantiation)->getTemplateSpecializationKind());
4471 } else if (InstantiatedFrom && isa<CXXRecordDecl>(Member)) {
4472 cast<CXXRecordDecl>(Member)->setInstantiationOfMemberClass(
4473 cast<CXXRecordDecl>(InstantiatedFrom),
4474 cast<CXXRecordDecl>(Instantiation)->getTemplateSpecializationKind());
4478 Previous.addDecl(Instantiation);
4482 // Make sure that this is a specialization of a member.
4483 if (!InstantiatedFrom) {
4484 Diag(Member->getLocation(), diag::err_spec_member_not_instantiated)
4486 Diag(Instantiation->getLocation(), diag::note_specialized_decl);
4490 // C++ [temp.expl.spec]p6:
4491 // If a template, a member template or the member of a class template is
4492 // explicitly specialized then that spe- cialization shall be declared
4493 // before the first use of that specialization that would cause an implicit
4494 // instantiation to take place, in every translation unit in which such a
4495 // use occurs; no diagnostic is required.
4496 assert(MSInfo && "Member specialization info missing?");
4498 bool HasNoEffect = false;
4499 if (CheckSpecializationInstantiationRedecl(Member->getLocation(),
4500 TSK_ExplicitSpecialization,
4502 MSInfo->getTemplateSpecializationKind(),
4503 MSInfo->getPointOfInstantiation(),
4507 // Check the scope of this explicit specialization.
4508 if (CheckTemplateSpecializationScope(*this,
4510 Instantiation, Member->getLocation(),
4514 // Note that this is an explicit instantiation of a member.
4515 // the original declaration to note that it is an explicit specialization
4516 // (if it was previously an implicit instantiation). This latter step
4517 // makes bookkeeping easier.
4518 if (isa<FunctionDecl>(Member)) {
4519 FunctionDecl *InstantiationFunction = cast<FunctionDecl>(Instantiation);
4520 if (InstantiationFunction->getTemplateSpecializationKind() ==
4521 TSK_ImplicitInstantiation) {
4522 InstantiationFunction->setTemplateSpecializationKind(
4523 TSK_ExplicitSpecialization);
4524 InstantiationFunction->setLocation(Member->getLocation());
4527 cast<FunctionDecl>(Member)->setInstantiationOfMemberFunction(
4528 cast<CXXMethodDecl>(InstantiatedFrom),
4529 TSK_ExplicitSpecialization);
4530 } else if (isa<VarDecl>(Member)) {
4531 VarDecl *InstantiationVar = cast<VarDecl>(Instantiation);
4532 if (InstantiationVar->getTemplateSpecializationKind() ==
4533 TSK_ImplicitInstantiation) {
4534 InstantiationVar->setTemplateSpecializationKind(
4535 TSK_ExplicitSpecialization);
4536 InstantiationVar->setLocation(Member->getLocation());
4539 Context.setInstantiatedFromStaticDataMember(cast<VarDecl>(Member),
4540 cast<VarDecl>(InstantiatedFrom),
4541 TSK_ExplicitSpecialization);
4543 assert(isa<CXXRecordDecl>(Member) && "Only member classes remain");
4544 CXXRecordDecl *InstantiationClass = cast<CXXRecordDecl>(Instantiation);
4545 if (InstantiationClass->getTemplateSpecializationKind() ==
4546 TSK_ImplicitInstantiation) {
4547 InstantiationClass->setTemplateSpecializationKind(
4548 TSK_ExplicitSpecialization);
4549 InstantiationClass->setLocation(Member->getLocation());
4552 cast<CXXRecordDecl>(Member)->setInstantiationOfMemberClass(
4553 cast<CXXRecordDecl>(InstantiatedFrom),
4554 TSK_ExplicitSpecialization);
4557 // Save the caller the trouble of having to figure out which declaration
4558 // this specialization matches.
4560 Previous.addDecl(Instantiation);
4564 /// \brief Check the scope of an explicit instantiation.
4566 /// \returns true if a serious error occurs, false otherwise.
4567 static bool CheckExplicitInstantiationScope(Sema &S, NamedDecl *D,
4568 SourceLocation InstLoc,
4569 bool WasQualifiedName) {
4570 DeclContext *ExpectedContext
4571 = D->getDeclContext()->getEnclosingNamespaceContext()->getLookupContext();
4572 DeclContext *CurContext = S.CurContext->getLookupContext();
4574 if (CurContext->isRecord()) {
4575 S.Diag(InstLoc, diag::err_explicit_instantiation_in_class)
4580 // C++0x [temp.explicit]p2:
4581 // An explicit instantiation shall appear in an enclosing namespace of its
4584 // This is DR275, which we do not retroactively apply to C++98/03.
4585 if (S.getLangOptions().CPlusPlus0x &&
4586 !CurContext->Encloses(ExpectedContext)) {
4587 if (NamespaceDecl *NS = dyn_cast<NamespaceDecl>(ExpectedContext))
4589 S.getLangOptions().CPlusPlus0x?
4590 diag::err_explicit_instantiation_out_of_scope
4591 : diag::warn_explicit_instantiation_out_of_scope_0x)
4595 S.getLangOptions().CPlusPlus0x?
4596 diag::err_explicit_instantiation_must_be_global
4597 : diag::warn_explicit_instantiation_out_of_scope_0x)
4599 S.Diag(D->getLocation(), diag::note_explicit_instantiation_here);
4603 // C++0x [temp.explicit]p2:
4604 // If the name declared in the explicit instantiation is an unqualified
4605 // name, the explicit instantiation shall appear in the namespace where
4606 // its template is declared or, if that namespace is inline (7.3.1), any
4607 // namespace from its enclosing namespace set.
4608 if (WasQualifiedName)
4611 if (CurContext->Equals(ExpectedContext))
4615 S.getLangOptions().CPlusPlus0x?
4616 diag::err_explicit_instantiation_unqualified_wrong_namespace
4617 : diag::warn_explicit_instantiation_unqualified_wrong_namespace_0x)
4618 << D << ExpectedContext;
4619 S.Diag(D->getLocation(), diag::note_explicit_instantiation_here);
4623 /// \brief Determine whether the given scope specifier has a template-id in it.
4624 static bool ScopeSpecifierHasTemplateId(const CXXScopeSpec &SS) {
4628 // C++0x [temp.explicit]p2:
4629 // If the explicit instantiation is for a member function, a member class
4630 // or a static data member of a class template specialization, the name of
4631 // the class template specialization in the qualified-id for the member
4632 // name shall be a simple-template-id.
4634 // C++98 has the same restriction, just worded differently.
4635 for (NestedNameSpecifier *NNS = (NestedNameSpecifier *)SS.getScopeRep();
4636 NNS; NNS = NNS->getPrefix())
4637 if (Type *T = NNS->getAsType())
4638 if (isa<TemplateSpecializationType>(T))
4644 // Explicit instantiation of a class template specialization
4646 Sema::ActOnExplicitInstantiation(Scope *S,
4647 SourceLocation ExternLoc,
4648 SourceLocation TemplateLoc,
4650 SourceLocation KWLoc,
4651 const CXXScopeSpec &SS,
4652 TemplateTy TemplateD,
4653 SourceLocation TemplateNameLoc,
4654 SourceLocation LAngleLoc,
4655 ASTTemplateArgsPtr TemplateArgsIn,
4656 SourceLocation RAngleLoc,
4657 AttributeList *Attr) {
4658 // Find the class template we're specializing
4659 TemplateName Name = TemplateD.getAsVal<TemplateName>();
4660 ClassTemplateDecl *ClassTemplate
4661 = cast<ClassTemplateDecl>(Name.getAsTemplateDecl());
4663 // Check that the specialization uses the same tag kind as the
4664 // original template.
4665 TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec);
4666 assert(Kind != TTK_Enum &&
4667 "Invalid enum tag in class template explicit instantiation!");
4668 if (!isAcceptableTagRedeclaration(ClassTemplate->getTemplatedDecl(),
4670 *ClassTemplate->getIdentifier())) {
4671 Diag(KWLoc, diag::err_use_with_wrong_tag)
4673 << FixItHint::CreateReplacement(KWLoc,
4674 ClassTemplate->getTemplatedDecl()->getKindName());
4675 Diag(ClassTemplate->getTemplatedDecl()->getLocation(),
4676 diag::note_previous_use);
4677 Kind = ClassTemplate->getTemplatedDecl()->getTagKind();
4680 // C++0x [temp.explicit]p2:
4681 // There are two forms of explicit instantiation: an explicit instantiation
4682 // definition and an explicit instantiation declaration. An explicit
4683 // instantiation declaration begins with the extern keyword. [...]
4684 TemplateSpecializationKind TSK
4685 = ExternLoc.isInvalid()? TSK_ExplicitInstantiationDefinition
4686 : TSK_ExplicitInstantiationDeclaration;
4688 // Translate the parser's template argument list in our AST format.
4689 TemplateArgumentListInfo TemplateArgs(LAngleLoc, RAngleLoc);
4690 translateTemplateArguments(TemplateArgsIn, TemplateArgs);
4692 // Check that the template argument list is well-formed for this
4694 TemplateArgumentListBuilder Converted(ClassTemplate->getTemplateParameters(),
4695 TemplateArgs.size());
4696 if (CheckTemplateArgumentList(ClassTemplate, TemplateNameLoc,
4697 TemplateArgs, false, Converted))
4700 assert((Converted.structuredSize() ==
4701 ClassTemplate->getTemplateParameters()->size()) &&
4702 "Converted template argument list is too short!");
4704 // Find the class template specialization declaration that
4705 // corresponds to these arguments.
4706 llvm::FoldingSetNodeID ID;
4707 ClassTemplateSpecializationDecl::Profile(ID,
4708 Converted.getFlatArguments(),
4709 Converted.flatSize(),
4711 void *InsertPos = 0;
4712 ClassTemplateSpecializationDecl *PrevDecl
4713 = ClassTemplate->getSpecializations().FindNodeOrInsertPos(ID, InsertPos);
4715 TemplateSpecializationKind PrevDecl_TSK
4716 = PrevDecl ? PrevDecl->getTemplateSpecializationKind() : TSK_Undeclared;
4718 // C++0x [temp.explicit]p2:
4719 // [...] An explicit instantiation shall appear in an enclosing
4720 // namespace of its template. [...]
4722 // This is C++ DR 275.
4723 if (CheckExplicitInstantiationScope(*this, ClassTemplate, TemplateNameLoc,
4727 ClassTemplateSpecializationDecl *Specialization = 0;
4729 bool ReusedDecl = false;
4730 bool HasNoEffect = false;
4732 if (CheckSpecializationInstantiationRedecl(TemplateNameLoc, TSK,
4733 PrevDecl, PrevDecl_TSK,
4734 PrevDecl->getPointOfInstantiation(),
4736 return DeclPtrTy::make(PrevDecl);
4738 // Even though HasNoEffect == true means that this explicit instantiation
4739 // has no effect on semantics, we go on to put its syntax in the AST.
4741 if (PrevDecl_TSK == TSK_ImplicitInstantiation ||
4742 PrevDecl_TSK == TSK_Undeclared) {
4743 // Since the only prior class template specialization with these
4744 // arguments was referenced but not declared, reuse that
4745 // declaration node as our own, updating the source location
4746 // for the template name to reflect our new declaration.
4747 // (Other source locations will be updated later.)
4748 Specialization = PrevDecl;
4749 Specialization->setLocation(TemplateNameLoc);
4755 if (!Specialization) {
4756 // Create a new class template specialization declaration node for
4757 // this explicit specialization.
4759 = ClassTemplateSpecializationDecl::Create(Context, Kind,
4760 ClassTemplate->getDeclContext(),
4763 Converted, PrevDecl);
4764 SetNestedNameSpecifier(Specialization, SS);
4768 // Remove the previous declaration from the folding set, since we want
4769 // to introduce a new declaration.
4770 ClassTemplate->getSpecializations().RemoveNode(PrevDecl);
4771 ClassTemplate->getSpecializations().FindNodeOrInsertPos(ID, InsertPos);
4773 // Insert the new specialization.
4774 ClassTemplate->getSpecializations().InsertNode(Specialization, InsertPos);
4778 // Build the fully-sugared type for this explicit instantiation as
4779 // the user wrote in the explicit instantiation itself. This means
4780 // that we'll pretty-print the type retrieved from the
4781 // specialization's declaration the way that the user actually wrote
4782 // the explicit instantiation, rather than formatting the name based
4783 // on the "canonical" representation used to store the template
4784 // arguments in the specialization.
4785 TypeSourceInfo *WrittenTy
4786 = Context.getTemplateSpecializationTypeInfo(Name, TemplateNameLoc,
4788 Context.getTypeDeclType(Specialization));
4789 Specialization->setTypeAsWritten(WrittenTy);
4790 TemplateArgsIn.release();
4792 // Set source locations for keywords.
4793 Specialization->setExternLoc(ExternLoc);
4794 Specialization->setTemplateKeywordLoc(TemplateLoc);
4796 // Add the explicit instantiation into its lexical context. However,
4797 // since explicit instantiations are never found by name lookup, we
4798 // just put it into the declaration context directly.
4799 Specialization->setLexicalDeclContext(CurContext);
4800 CurContext->addDecl(Specialization);
4802 // Syntax is now OK, so return if it has no other effect on semantics.
4804 // Set the template specialization kind.
4805 Specialization->setTemplateSpecializationKind(TSK);
4806 return DeclPtrTy::make(Specialization);
4809 // C++ [temp.explicit]p3:
4810 // A definition of a class template or class member template
4811 // shall be in scope at the point of the explicit instantiation of
4812 // the class template or class member template.
4814 // This check comes when we actually try to perform the
4816 ClassTemplateSpecializationDecl *Def
4817 = cast_or_null<ClassTemplateSpecializationDecl>(
4818 Specialization->getDefinition());
4820 InstantiateClassTemplateSpecialization(TemplateNameLoc, Specialization, TSK);
4821 else if (TSK == TSK_ExplicitInstantiationDefinition) {
4822 MarkVTableUsed(TemplateNameLoc, Specialization, true);
4823 Specialization->setPointOfInstantiation(Def->getPointOfInstantiation());
4826 // Instantiate the members of this class template specialization.
4827 Def = cast_or_null<ClassTemplateSpecializationDecl>(
4828 Specialization->getDefinition());
4830 TemplateSpecializationKind Old_TSK = Def->getTemplateSpecializationKind();
4832 // Fix a TSK_ExplicitInstantiationDeclaration followed by a
4833 // TSK_ExplicitInstantiationDefinition
4834 if (Old_TSK == TSK_ExplicitInstantiationDeclaration &&
4835 TSK == TSK_ExplicitInstantiationDefinition)
4836 Def->setTemplateSpecializationKind(TSK);
4838 InstantiateClassTemplateSpecializationMembers(TemplateNameLoc, Def, TSK);
4841 // Set the template specialization kind.
4842 Specialization->setTemplateSpecializationKind(TSK);
4843 return DeclPtrTy::make(Specialization);
4846 // Explicit instantiation of a member class of a class template.
4848 Sema::ActOnExplicitInstantiation(Scope *S,
4849 SourceLocation ExternLoc,
4850 SourceLocation TemplateLoc,
4852 SourceLocation KWLoc,
4854 IdentifierInfo *Name,
4855 SourceLocation NameLoc,
4856 AttributeList *Attr) {
4859 bool IsDependent = false;
4860 DeclPtrTy TagD = ActOnTag(S, TagSpec, Action::TUK_Reference,
4861 KWLoc, SS, Name, NameLoc, Attr, AS_none,
4862 MultiTemplateParamsArg(*this, 0, 0),
4863 Owned, IsDependent);
4864 assert(!IsDependent && "explicit instantiation of dependent name not yet handled");
4869 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>());
4870 if (Tag->isEnum()) {
4871 Diag(TemplateLoc, diag::err_explicit_instantiation_enum)
4872 << Context.getTypeDeclType(Tag);
4876 if (Tag->isInvalidDecl())
4879 CXXRecordDecl *Record = cast<CXXRecordDecl>(Tag);
4880 CXXRecordDecl *Pattern = Record->getInstantiatedFromMemberClass();
4882 Diag(TemplateLoc, diag::err_explicit_instantiation_nontemplate_type)
4883 << Context.getTypeDeclType(Record);
4884 Diag(Record->getLocation(), diag::note_nontemplate_decl_here);
4888 // C++0x [temp.explicit]p2:
4889 // If the explicit instantiation is for a class or member class, the
4890 // elaborated-type-specifier in the declaration shall include a
4891 // simple-template-id.
4893 // C++98 has the same restriction, just worded differently.
4894 if (!ScopeSpecifierHasTemplateId(SS))
4895 Diag(TemplateLoc, diag::ext_explicit_instantiation_without_qualified_id)
4896 << Record << SS.getRange();
4898 // C++0x [temp.explicit]p2:
4899 // There are two forms of explicit instantiation: an explicit instantiation
4900 // definition and an explicit instantiation declaration. An explicit
4901 // instantiation declaration begins with the extern keyword. [...]
4902 TemplateSpecializationKind TSK
4903 = ExternLoc.isInvalid()? TSK_ExplicitInstantiationDefinition
4904 : TSK_ExplicitInstantiationDeclaration;
4906 // C++0x [temp.explicit]p2:
4907 // [...] An explicit instantiation shall appear in an enclosing
4908 // namespace of its template. [...]
4910 // This is C++ DR 275.
4911 CheckExplicitInstantiationScope(*this, Record, NameLoc, true);
4913 // Verify that it is okay to explicitly instantiate here.
4914 CXXRecordDecl *PrevDecl
4915 = cast_or_null<CXXRecordDecl>(Record->getPreviousDeclaration());
4916 if (!PrevDecl && Record->getDefinition())
4919 MemberSpecializationInfo *MSInfo = PrevDecl->getMemberSpecializationInfo();
4920 bool HasNoEffect = false;
4921 assert(MSInfo && "No member specialization information?");
4922 if (CheckSpecializationInstantiationRedecl(TemplateLoc, TSK,
4924 MSInfo->getTemplateSpecializationKind(),
4925 MSInfo->getPointOfInstantiation(),
4932 CXXRecordDecl *RecordDef
4933 = cast_or_null<CXXRecordDecl>(Record->getDefinition());
4935 // C++ [temp.explicit]p3:
4936 // A definition of a member class of a class template shall be in scope
4937 // at the point of an explicit instantiation of the member class.
4939 = cast_or_null<CXXRecordDecl>(Pattern->getDefinition());
4941 Diag(TemplateLoc, diag::err_explicit_instantiation_undefined_member)
4942 << 0 << Record->getDeclName() << Record->getDeclContext();
4943 Diag(Pattern->getLocation(), diag::note_forward_declaration)
4947 if (InstantiateClass(NameLoc, Record, Def,
4948 getTemplateInstantiationArgs(Record),
4952 RecordDef = cast_or_null<CXXRecordDecl>(Record->getDefinition());
4958 // Instantiate all of the members of the class.
4959 InstantiateClassMembers(NameLoc, RecordDef,
4960 getTemplateInstantiationArgs(Record), TSK);
4962 if (TSK == TSK_ExplicitInstantiationDefinition)
4963 MarkVTableUsed(NameLoc, RecordDef, true);
4965 // FIXME: We don't have any representation for explicit instantiations of
4966 // member classes. Such a representation is not needed for compilation, but it
4967 // should be available for clients that want to see all of the declarations in
4972 Sema::DeclResult Sema::ActOnExplicitInstantiation(Scope *S,
4973 SourceLocation ExternLoc,
4974 SourceLocation TemplateLoc,
4976 // Explicit instantiations always require a name.
4977 DeclarationName Name = GetNameForDeclarator(D);
4979 if (!D.isInvalidType())
4980 Diag(D.getDeclSpec().getSourceRange().getBegin(),
4981 diag::err_explicit_instantiation_requires_name)
4982 << D.getDeclSpec().getSourceRange()
4983 << D.getSourceRange();
4988 // The scope passed in may not be a decl scope. Zip up the scope tree until
4989 // we find one that is.
4990 while ((S->getFlags() & Scope::DeclScope) == 0 ||
4991 (S->getFlags() & Scope::TemplateParamScope) != 0)
4994 // Determine the type of the declaration.
4995 TypeSourceInfo *T = GetTypeForDeclarator(D, S);
4996 QualType R = T->getType();
5000 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) {
5001 // Cannot explicitly instantiate a typedef.
5002 Diag(D.getIdentifierLoc(), diag::err_explicit_instantiation_of_typedef)
5007 // C++0x [temp.explicit]p1:
5008 // [...] An explicit instantiation of a function template shall not use the
5009 // inline or constexpr specifiers.
5010 // Presumably, this also applies to member functions of class templates as
5012 if (D.getDeclSpec().isInlineSpecified() && getLangOptions().CPlusPlus0x)
5013 Diag(D.getDeclSpec().getInlineSpecLoc(),
5014 diag::err_explicit_instantiation_inline)
5015 <<FixItHint::CreateRemoval(D.getDeclSpec().getInlineSpecLoc());
5017 // FIXME: check for constexpr specifier.
5019 // C++0x [temp.explicit]p2:
5020 // There are two forms of explicit instantiation: an explicit instantiation
5021 // definition and an explicit instantiation declaration. An explicit
5022 // instantiation declaration begins with the extern keyword. [...]
5023 TemplateSpecializationKind TSK
5024 = ExternLoc.isInvalid()? TSK_ExplicitInstantiationDefinition
5025 : TSK_ExplicitInstantiationDeclaration;
5027 LookupResult Previous(*this, Name, D.getIdentifierLoc(), LookupOrdinaryName);
5028 LookupParsedName(Previous, S, &D.getCXXScopeSpec());
5030 if (!R->isFunctionType()) {
5031 // C++ [temp.explicit]p1:
5032 // A [...] static data member of a class template can be explicitly
5033 // instantiated from the member definition associated with its class
5035 if (Previous.isAmbiguous())
5038 VarDecl *Prev = Previous.getAsSingle<VarDecl>();
5039 if (!Prev || !Prev->isStaticDataMember()) {
5040 // We expect to see a data data member here.
5041 Diag(D.getIdentifierLoc(), diag::err_explicit_instantiation_not_known)
5043 for (LookupResult::iterator P = Previous.begin(), PEnd = Previous.end();
5045 Diag((*P)->getLocation(), diag::note_explicit_instantiation_here);
5049 if (!Prev->getInstantiatedFromStaticDataMember()) {
5050 // FIXME: Check for explicit specialization?
5051 Diag(D.getIdentifierLoc(),
5052 diag::err_explicit_instantiation_data_member_not_instantiated)
5054 Diag(Prev->getLocation(), diag::note_explicit_instantiation_here);
5055 // FIXME: Can we provide a note showing where this was declared?
5059 // C++0x [temp.explicit]p2:
5060 // If the explicit instantiation is for a member function, a member class
5061 // or a static data member of a class template specialization, the name of
5062 // the class template specialization in the qualified-id for the member
5063 // name shall be a simple-template-id.
5065 // C++98 has the same restriction, just worded differently.
5066 if (!ScopeSpecifierHasTemplateId(D.getCXXScopeSpec()))
5067 Diag(D.getIdentifierLoc(),
5068 diag::ext_explicit_instantiation_without_qualified_id)
5069 << Prev << D.getCXXScopeSpec().getRange();
5071 // Check the scope of this explicit instantiation.
5072 CheckExplicitInstantiationScope(*this, Prev, D.getIdentifierLoc(), true);
5074 // Verify that it is okay to explicitly instantiate here.
5075 MemberSpecializationInfo *MSInfo = Prev->getMemberSpecializationInfo();
5076 assert(MSInfo && "Missing static data member specialization info?");
5077 bool HasNoEffect = false;
5078 if (CheckSpecializationInstantiationRedecl(D.getIdentifierLoc(), TSK, Prev,
5079 MSInfo->getTemplateSpecializationKind(),
5080 MSInfo->getPointOfInstantiation(),
5086 // Instantiate static data member.
5087 Prev->setTemplateSpecializationKind(TSK, D.getIdentifierLoc());
5088 if (TSK == TSK_ExplicitInstantiationDefinition)
5089 InstantiateStaticDataMemberDefinition(D.getIdentifierLoc(), Prev, false,
5090 /*DefinitionRequired=*/true);
5092 // FIXME: Create an ExplicitInstantiation node?
5096 // If the declarator is a template-id, translate the parser's template
5097 // argument list into our AST format.
5098 bool HasExplicitTemplateArgs = false;
5099 TemplateArgumentListInfo TemplateArgs;
5100 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) {
5101 TemplateIdAnnotation *TemplateId = D.getName().TemplateId;
5102 TemplateArgs.setLAngleLoc(TemplateId->LAngleLoc);
5103 TemplateArgs.setRAngleLoc(TemplateId->RAngleLoc);
5104 ASTTemplateArgsPtr TemplateArgsPtr(*this,
5105 TemplateId->getTemplateArgs(),
5106 TemplateId->NumArgs);
5107 translateTemplateArguments(TemplateArgsPtr, TemplateArgs);
5108 HasExplicitTemplateArgs = true;
5109 TemplateArgsPtr.release();
5112 // C++ [temp.explicit]p1:
5113 // A [...] function [...] can be explicitly instantiated from its template.
5114 // A member function [...] of a class template can be explicitly
5115 // instantiated from the member definition associated with its class
5117 UnresolvedSet<8> Matches;
5118 for (LookupResult::iterator P = Previous.begin(), PEnd = Previous.end();
5120 NamedDecl *Prev = *P;
5121 if (!HasExplicitTemplateArgs) {
5122 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Prev)) {
5123 if (Context.hasSameUnqualifiedType(Method->getType(), R)) {
5126 Matches.addDecl(Method, P.getAccess());
5127 if (Method->getTemplateSpecializationKind() == TSK_Undeclared)
5133 FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(Prev);
5137 TemplateDeductionInfo Info(Context, D.getIdentifierLoc());
5138 FunctionDecl *Specialization = 0;
5139 if (TemplateDeductionResult TDK
5140 = DeduceTemplateArguments(FunTmpl,
5141 (HasExplicitTemplateArgs ? &TemplateArgs : 0),
5142 R, Specialization, Info)) {
5143 // FIXME: Keep track of almost-matches?
5148 Matches.addDecl(Specialization, P.getAccess());
5151 // Find the most specialized function template specialization.
5152 UnresolvedSetIterator Result
5153 = getMostSpecialized(Matches.begin(), Matches.end(), TPOC_Other,
5154 D.getIdentifierLoc(),
5155 PDiag(diag::err_explicit_instantiation_not_known) << Name,
5156 PDiag(diag::err_explicit_instantiation_ambiguous) << Name,
5157 PDiag(diag::note_explicit_instantiation_candidate));
5159 if (Result == Matches.end())
5162 // Ignore access control bits, we don't need them for redeclaration checking.
5163 FunctionDecl *Specialization = cast<FunctionDecl>(*Result);
5165 if (Specialization->getTemplateSpecializationKind() == TSK_Undeclared) {
5166 Diag(D.getIdentifierLoc(),
5167 diag::err_explicit_instantiation_member_function_not_instantiated)
5169 << (Specialization->getTemplateSpecializationKind() ==
5170 TSK_ExplicitSpecialization);
5171 Diag(Specialization->getLocation(), diag::note_explicit_instantiation_here);
5175 FunctionDecl *PrevDecl = Specialization->getPreviousDeclaration();
5176 if (!PrevDecl && Specialization->isThisDeclarationADefinition())
5177 PrevDecl = Specialization;
5180 bool HasNoEffect = false;
5181 if (CheckSpecializationInstantiationRedecl(D.getIdentifierLoc(), TSK,
5183 PrevDecl->getTemplateSpecializationKind(),
5184 PrevDecl->getPointOfInstantiation(),
5188 // FIXME: We may still want to build some representation of this
5189 // explicit specialization.
5194 Specialization->setTemplateSpecializationKind(TSK, D.getIdentifierLoc());
5196 if (TSK == TSK_ExplicitInstantiationDefinition)
5197 InstantiateFunctionDefinition(D.getIdentifierLoc(), Specialization,
5198 false, /*DefinitionRequired=*/true);
5200 // C++0x [temp.explicit]p2:
5201 // If the explicit instantiation is for a member function, a member class
5202 // or a static data member of a class template specialization, the name of
5203 // the class template specialization in the qualified-id for the member
5204 // name shall be a simple-template-id.
5206 // C++98 has the same restriction, just worded differently.
5207 FunctionTemplateDecl *FunTmpl = Specialization->getPrimaryTemplate();
5208 if (D.getName().getKind() != UnqualifiedId::IK_TemplateId && !FunTmpl &&
5209 D.getCXXScopeSpec().isSet() &&
5210 !ScopeSpecifierHasTemplateId(D.getCXXScopeSpec()))
5211 Diag(D.getIdentifierLoc(),
5212 diag::ext_explicit_instantiation_without_qualified_id)
5213 << Specialization << D.getCXXScopeSpec().getRange();
5215 CheckExplicitInstantiationScope(*this,
5216 FunTmpl? (NamedDecl *)FunTmpl
5217 : Specialization->getInstantiatedFromMemberFunction(),
5218 D.getIdentifierLoc(),
5219 D.getCXXScopeSpec().isSet());
5221 // FIXME: Create some kind of ExplicitInstantiationDecl here.
5226 Sema::ActOnDependentTag(Scope *S, unsigned TagSpec, TagUseKind TUK,
5227 const CXXScopeSpec &SS, IdentifierInfo *Name,
5228 SourceLocation TagLoc, SourceLocation NameLoc) {
5229 // This has to hold, because SS is expected to be defined.
5230 assert(Name && "Expected a name in a dependent tag");
5232 NestedNameSpecifier *NNS
5233 = static_cast<NestedNameSpecifier *>(SS.getScopeRep());
5237 TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec);
5239 if (TUK == TUK_Declaration || TUK == TUK_Definition) {
5240 Diag(NameLoc, diag::err_dependent_tag_decl)
5241 << (TUK == TUK_Definition) << Kind << SS.getRange();
5245 ElaboratedTypeKeyword Kwd = TypeWithKeyword::getKeywordForTagTypeKind(Kind);
5246 return Context.getDependentNameType(Kwd, NNS, Name).getAsOpaquePtr();
5250 Sema::ActOnTypenameType(Scope *S, SourceLocation TypenameLoc,
5251 const CXXScopeSpec &SS, const IdentifierInfo &II,
5252 SourceLocation IdLoc) {
5253 NestedNameSpecifier *NNS
5254 = static_cast<NestedNameSpecifier *>(SS.getScopeRep());
5258 if (TypenameLoc.isValid() && S && !S->getTemplateParamParent() &&
5259 !getLangOptions().CPlusPlus0x)
5260 Diag(TypenameLoc, diag::ext_typename_outside_of_template)
5261 << FixItHint::CreateRemoval(TypenameLoc);
5263 QualType T = CheckTypenameType(ETK_Typename, NNS, II,
5264 TypenameLoc, SS.getRange(), IdLoc);
5268 TypeSourceInfo *TSI = Context.CreateTypeSourceInfo(T);
5269 if (isa<DependentNameType>(T)) {
5270 DependentNameTypeLoc TL = cast<DependentNameTypeLoc>(TSI->getTypeLoc());
5271 TL.setKeywordLoc(TypenameLoc);
5272 TL.setQualifierRange(SS.getRange());
5273 TL.setNameLoc(IdLoc);
5275 ElaboratedTypeLoc TL = cast<ElaboratedTypeLoc>(TSI->getTypeLoc());
5276 TL.setKeywordLoc(TypenameLoc);
5277 TL.setQualifierRange(SS.getRange());
5278 cast<TypeSpecTypeLoc>(TL.getNamedTypeLoc()).setNameLoc(IdLoc);
5281 return CreateLocInfoType(T, TSI).getAsOpaquePtr();
5285 Sema::ActOnTypenameType(Scope *S, SourceLocation TypenameLoc,
5286 const CXXScopeSpec &SS, SourceLocation TemplateLoc,
5288 if (TypenameLoc.isValid() && S && !S->getTemplateParamParent() &&
5289 !getLangOptions().CPlusPlus0x)
5290 Diag(TypenameLoc, diag::ext_typename_outside_of_template)
5291 << FixItHint::CreateRemoval(TypenameLoc);
5293 TypeSourceInfo *InnerTSI = 0;
5294 QualType T = GetTypeFromParser(Ty, &InnerTSI);
5295 NestedNameSpecifier *NNS
5296 = static_cast<NestedNameSpecifier *>(SS.getScopeRep());
5298 assert(isa<TemplateSpecializationType>(T) &&
5299 "Expected a template specialization type");
5301 if (computeDeclContext(SS, false)) {
5302 // If we can compute a declaration context, then the "typename"
5303 // keyword was superfluous. Just build an ElaboratedType to keep
5304 // track of the nested-name-specifier.
5306 // Push the inner type, preserving its source locations if possible.
5307 TypeLocBuilder Builder;
5309 Builder.pushFullCopy(InnerTSI->getTypeLoc());
5311 Builder.push<TemplateSpecializationTypeLoc>(T).initialize(TemplateLoc);
5313 T = Context.getElaboratedType(ETK_Typename, NNS, T);
5314 ElaboratedTypeLoc TL = Builder.push<ElaboratedTypeLoc>(T);
5315 TL.setKeywordLoc(TypenameLoc);
5316 TL.setQualifierRange(SS.getRange());
5318 TypeSourceInfo *TSI = Builder.getTypeSourceInfo(Context, T);
5319 return CreateLocInfoType(T, TSI).getAsOpaquePtr();
5322 // TODO: it's really silly that we make a template specialization
5323 // type earlier only to drop it again here.
5324 TemplateSpecializationType *TST = cast<TemplateSpecializationType>(T);
5325 DependentTemplateName *DTN =
5326 TST->getTemplateName().getAsDependentTemplateName();
5327 assert(DTN && "dependent template has non-dependent name?");
5328 T = Context.getDependentTemplateSpecializationType(ETK_Typename, NNS,
5329 DTN->getIdentifier(),
5332 TypeSourceInfo *TSI = Context.CreateTypeSourceInfo(T);
5333 DependentTemplateSpecializationTypeLoc TL =
5334 cast<DependentTemplateSpecializationTypeLoc>(TSI->getTypeLoc());
5336 TemplateSpecializationTypeLoc TSTL =
5337 cast<TemplateSpecializationTypeLoc>(InnerTSI->getTypeLoc());
5338 TL.setLAngleLoc(TSTL.getLAngleLoc());
5339 TL.setRAngleLoc(TSTL.getRAngleLoc());
5340 for (unsigned I = 0, E = TST->getNumArgs(); I != E; ++I)
5341 TL.setArgLocInfo(I, TSTL.getArgLocInfo(I));
5343 TL.initializeLocal(SourceLocation());
5345 TL.setKeywordLoc(TypenameLoc);
5346 TL.setQualifierRange(SS.getRange());
5347 return CreateLocInfoType(T, TSI).getAsOpaquePtr();
5350 /// \brief Build the type that describes a C++ typename specifier,
5351 /// e.g., "typename T::type".
5353 Sema::CheckTypenameType(ElaboratedTypeKeyword Keyword,
5354 NestedNameSpecifier *NNS, const IdentifierInfo &II,
5355 SourceLocation KeywordLoc, SourceRange NNSRange,
5356 SourceLocation IILoc) {
5358 SS.setScopeRep(NNS);
5359 SS.setRange(NNSRange);
5361 DeclContext *Ctx = computeDeclContext(SS);
5363 // If the nested-name-specifier is dependent and couldn't be
5364 // resolved to a type, build a typename type.
5365 assert(NNS->isDependent());
5366 return Context.getDependentNameType(Keyword, NNS, &II);
5369 // If the nested-name-specifier refers to the current instantiation,
5370 // the "typename" keyword itself is superfluous. In C++03, the
5371 // program is actually ill-formed. However, DR 382 (in C++0x CD1)
5372 // allows such extraneous "typename" keywords, and we retroactively
5373 // apply this DR to C++03 code with only a warning. In any case we continue.
5375 if (RequireCompleteDeclContext(SS, Ctx))
5378 DeclarationName Name(&II);
5379 LookupResult Result(*this, Name, IILoc, LookupOrdinaryName);
5380 LookupQualifiedName(Result, Ctx);
5381 unsigned DiagID = 0;
5382 Decl *Referenced = 0;
5383 switch (Result.getResultKind()) {
5384 case LookupResult::NotFound:
5385 DiagID = diag::err_typename_nested_not_found;
5388 case LookupResult::NotFoundInCurrentInstantiation:
5389 // Okay, it's a member of an unknown instantiation.
5390 return Context.getDependentNameType(Keyword, NNS, &II);
5392 case LookupResult::Found:
5393 if (TypeDecl *Type = dyn_cast<TypeDecl>(Result.getFoundDecl())) {
5394 // We found a type. Build an ElaboratedType, since the
5395 // typename-specifier was just sugar.
5396 return Context.getElaboratedType(ETK_Typename, NNS,
5397 Context.getTypeDeclType(Type));
5400 DiagID = diag::err_typename_nested_not_type;
5401 Referenced = Result.getFoundDecl();
5404 case LookupResult::FoundUnresolvedValue:
5405 llvm_unreachable("unresolved using decl in non-dependent context");
5408 case LookupResult::FoundOverloaded:
5409 DiagID = diag::err_typename_nested_not_type;
5410 Referenced = *Result.begin();
5413 case LookupResult::Ambiguous:
5417 // If we get here, it's because name lookup did not find a
5418 // type. Emit an appropriate diagnostic and return an error.
5419 SourceRange FullRange(KeywordLoc.isValid() ? KeywordLoc : NNSRange.getBegin(),
5421 Diag(IILoc, DiagID) << FullRange << Name << Ctx;
5423 Diag(Referenced->getLocation(), diag::note_typename_refers_here)
5429 // See Sema::RebuildTypeInCurrentInstantiation
5430 class CurrentInstantiationRebuilder
5431 : public TreeTransform<CurrentInstantiationRebuilder> {
5433 DeclarationName Entity;
5436 typedef TreeTransform<CurrentInstantiationRebuilder> inherited;
5438 CurrentInstantiationRebuilder(Sema &SemaRef,
5440 DeclarationName Entity)
5441 : TreeTransform<CurrentInstantiationRebuilder>(SemaRef),
5442 Loc(Loc), Entity(Entity) { }
5444 /// \brief Determine whether the given type \p T has already been
5447 /// For the purposes of type reconstruction, a type has already been
5448 /// transformed if it is NULL or if it is not dependent.
5449 bool AlreadyTransformed(QualType T) {
5450 return T.isNull() || !T->isDependentType();
5453 /// \brief Returns the location of the entity whose type is being
5455 SourceLocation getBaseLocation() { return Loc; }
5457 /// \brief Returns the name of the entity whose type is being rebuilt.
5458 DeclarationName getBaseEntity() { return Entity; }
5460 /// \brief Sets the "base" location and entity when that
5461 /// information is known based on another transformation.
5462 void setBase(SourceLocation Loc, DeclarationName Entity) {
5464 this->Entity = Entity;
5467 /// \brief Transforms an expression by returning the expression itself
5468 /// (an identity function).
5470 /// FIXME: This is completely unsafe; we will need to actually clone the
5472 Sema::OwningExprResult TransformExpr(Expr *E) {
5473 return getSema().Owned(E->Retain());
5478 /// \brief Rebuilds a type within the context of the current instantiation.
5480 /// The type \p T is part of the type of an out-of-line member definition of
5481 /// a class template (or class template partial specialization) that was parsed
5482 /// and constructed before we entered the scope of the class template (or
5483 /// partial specialization thereof). This routine will rebuild that type now
5484 /// that we have entered the declarator's scope, which may produce different
5485 /// canonical types, e.g.,
5488 /// template<typename T>
5490 /// typedef T* pointer;
5494 /// template<typename T>
5495 /// typename X<T>::pointer X<T>::data() { ... }
5498 /// Here, the type "typename X<T>::pointer" will be created as a DependentNameType,
5499 /// since we do not know that we can look into X<T> when we parsed the type.
5500 /// This function will rebuild the type, performing the lookup of "pointer"
5501 /// in X<T> and returning an ElaboratedType whose canonical type is the same
5502 /// as the canonical type of T*, allowing the return types of the out-of-line
5503 /// definition and the declaration to match.
5504 TypeSourceInfo *Sema::RebuildTypeInCurrentInstantiation(TypeSourceInfo *T,
5506 DeclarationName Name) {
5507 if (!T || !T->getType()->isDependentType())
5510 CurrentInstantiationRebuilder Rebuilder(*this, Loc, Name);
5511 return Rebuilder.TransformType(T);
5514 bool Sema::RebuildNestedNameSpecifierInCurrentInstantiation(CXXScopeSpec &SS) {
5515 if (SS.isInvalid()) return true;
5517 NestedNameSpecifier *NNS = static_cast<NestedNameSpecifier*>(SS.getScopeRep());
5518 CurrentInstantiationRebuilder Rebuilder(*this, SS.getRange().getBegin(),
5520 NestedNameSpecifier *Rebuilt =
5521 Rebuilder.TransformNestedNameSpecifier(NNS, SS.getRange());
5522 if (!Rebuilt) return true;
5524 SS.setScopeRep(Rebuilt);
5528 /// \brief Produces a formatted string that describes the binding of
5529 /// template parameters to template arguments.
5531 Sema::getTemplateArgumentBindingsText(const TemplateParameterList *Params,
5532 const TemplateArgumentList &Args) {
5533 // FIXME: For variadic templates, we'll need to get the structured list.
5534 return getTemplateArgumentBindingsText(Params, Args.getFlatArgumentList(),
5539 Sema::getTemplateArgumentBindingsText(const TemplateParameterList *Params,
5540 const TemplateArgument *Args,
5544 if (!Params || Params->size() == 0 || NumArgs == 0)
5547 for (unsigned I = 0, N = Params->size(); I != N; ++I) {
5556 if (const IdentifierInfo *Id = Params->getParam(I)->getIdentifier()) {
5557 Result += Id->getName();
5560 Result += llvm::utostr(I);
5565 switch (Args[I].getKind()) {
5566 case TemplateArgument::Null:
5567 Result += "<no value>";
5570 case TemplateArgument::Type: {
5571 std::string TypeStr;
5572 Args[I].getAsType().getAsStringInternal(TypeStr,
5573 Context.PrintingPolicy);
5578 case TemplateArgument::Declaration: {
5579 bool Unnamed = true;
5580 if (NamedDecl *ND = dyn_cast_or_null<NamedDecl>(Args[I].getAsDecl())) {
5581 if (ND->getDeclName()) {
5583 Result += ND->getNameAsString();
5588 Result += "<anonymous>";
5593 case TemplateArgument::Template: {
5595 llvm::raw_string_ostream OS(Str);
5596 Args[I].getAsTemplate().print(OS, Context.PrintingPolicy);
5601 case TemplateArgument::Integral: {
5602 Result += Args[I].getAsIntegral()->toString(10);
5606 case TemplateArgument::Expression: {
5607 // FIXME: This is non-optimal, since we're regurgitating the
5608 // expression we were given.
5611 llvm::raw_string_ostream OS(Str);
5612 Args[I].getAsExpr()->printPretty(OS, Context, 0,
5613 Context.PrintingPolicy);
5619 case TemplateArgument::Pack:
5620 // FIXME: Format template argument packs
5621 Result += "<template argument pack>";