1 //===------- SemaTemplate.cpp - Semantic Analysis for C++ Templates -------===/
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //===----------------------------------------------------------------------===/
9 // This file implements semantic analysis for C++ templates.
10 //===----------------------------------------------------------------------===/
12 #include "clang/Sema/SemaInternal.h"
13 #include "clang/Sema/Lookup.h"
14 #include "clang/Sema/Scope.h"
15 #include "clang/Sema/Template.h"
16 #include "clang/Sema/TemplateDeduction.h"
17 #include "TreeTransform.h"
18 #include "clang/AST/ASTContext.h"
19 #include "clang/AST/Expr.h"
20 #include "clang/AST/ExprCXX.h"
21 #include "clang/AST/DeclFriend.h"
22 #include "clang/AST/DeclTemplate.h"
23 #include "clang/Sema/DeclSpec.h"
24 #include "clang/Sema/ParsedTemplate.h"
25 #include "clang/Basic/LangOptions.h"
26 #include "clang/Basic/PartialDiagnostic.h"
27 #include "llvm/ADT/StringExtras.h"
28 using namespace clang;
31 /// \brief Determine whether the declaration found is acceptable as the name
32 /// of a template and, if so, return that template declaration. Otherwise,
34 static NamedDecl *isAcceptableTemplateName(ASTContext &Context,
36 NamedDecl *D = Orig->getUnderlyingDecl();
38 if (isa<TemplateDecl>(D))
41 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(D)) {
42 // C++ [temp.local]p1:
43 // Like normal (non-template) classes, class templates have an
44 // injected-class-name (Clause 9). The injected-class-name
45 // can be used with or without a template-argument-list. When
46 // it is used without a template-argument-list, it is
47 // equivalent to the injected-class-name followed by the
48 // template-parameters of the class template enclosed in
49 // <>. When it is used with a template-argument-list, it
50 // refers to the specified class template specialization,
51 // which could be the current specialization or another
53 if (Record->isInjectedClassName()) {
54 Record = cast<CXXRecordDecl>(Record->getDeclContext());
55 if (Record->getDescribedClassTemplate())
56 return Record->getDescribedClassTemplate();
58 if (ClassTemplateSpecializationDecl *Spec
59 = dyn_cast<ClassTemplateSpecializationDecl>(Record))
60 return Spec->getSpecializedTemplate();
69 static void FilterAcceptableTemplateNames(ASTContext &C, LookupResult &R) {
70 // The set of class templates we've already seen.
71 llvm::SmallPtrSet<ClassTemplateDecl *, 8> ClassTemplates;
72 LookupResult::Filter filter = R.makeFilter();
73 while (filter.hasNext()) {
74 NamedDecl *Orig = filter.next();
75 NamedDecl *Repl = isAcceptableTemplateName(C, Orig);
78 else if (Repl != Orig) {
80 // C++ [temp.local]p3:
81 // A lookup that finds an injected-class-name (10.2) can result in an
82 // ambiguity in certain cases (for example, if it is found in more than
83 // one base class). If all of the injected-class-names that are found
84 // refer to specializations of the same class template, and if the name
85 // is followed by a template-argument-list, the reference refers to the
86 // class template itself and not a specialization thereof, and is not
89 // FIXME: Will we eventually have to do the same for alias templates?
90 if (ClassTemplateDecl *ClassTmpl = dyn_cast<ClassTemplateDecl>(Repl))
91 if (!ClassTemplates.insert(ClassTmpl)) {
96 // FIXME: we promote access to public here as a workaround to
97 // the fact that LookupResult doesn't let us remember that we
98 // found this template through a particular injected class name,
99 // which means we end up doing nasty things to the invariants.
100 // Pretending that access is public is *much* safer.
101 filter.replace(Repl, AS_public);
107 TemplateNameKind Sema::isTemplateName(Scope *S,
109 bool hasTemplateKeyword,
111 ParsedType ObjectTypePtr,
112 bool EnteringContext,
113 TemplateTy &TemplateResult,
114 bool &MemberOfUnknownSpecialization) {
115 assert(getLangOptions().CPlusPlus && "No template names in C!");
117 DeclarationName TName;
118 MemberOfUnknownSpecialization = false;
120 switch (Name.getKind()) {
121 case UnqualifiedId::IK_Identifier:
122 TName = DeclarationName(Name.Identifier);
125 case UnqualifiedId::IK_OperatorFunctionId:
126 TName = Context.DeclarationNames.getCXXOperatorName(
127 Name.OperatorFunctionId.Operator);
130 case UnqualifiedId::IK_LiteralOperatorId:
131 TName = Context.DeclarationNames.getCXXLiteralOperatorName(Name.Identifier);
135 return TNK_Non_template;
138 QualType ObjectType = ObjectTypePtr.get();
140 LookupResult R(*this, TName, Name.getSourceRange().getBegin(),
142 LookupTemplateName(R, S, SS, ObjectType, EnteringContext,
143 MemberOfUnknownSpecialization);
144 if (R.empty()) return TNK_Non_template;
145 if (R.isAmbiguous()) {
146 // Suppress diagnostics; we'll redo this lookup later.
147 R.suppressDiagnostics();
149 // FIXME: we might have ambiguous templates, in which case we
150 // should at least parse them properly!
151 return TNK_Non_template;
154 TemplateName Template;
155 TemplateNameKind TemplateKind;
157 unsigned ResultCount = R.end() - R.begin();
158 if (ResultCount > 1) {
159 // We assume that we'll preserve the qualifier from a function
160 // template name in other ways.
161 Template = Context.getOverloadedTemplateName(R.begin(), R.end());
162 TemplateKind = TNK_Function_template;
164 // We'll do this lookup again later.
165 R.suppressDiagnostics();
167 TemplateDecl *TD = cast<TemplateDecl>((*R.begin())->getUnderlyingDecl());
169 if (SS.isSet() && !SS.isInvalid()) {
170 NestedNameSpecifier *Qualifier
171 = static_cast<NestedNameSpecifier *>(SS.getScopeRep());
172 Template = Context.getQualifiedTemplateName(Qualifier,
173 hasTemplateKeyword, TD);
175 Template = TemplateName(TD);
178 if (isa<FunctionTemplateDecl>(TD)) {
179 TemplateKind = TNK_Function_template;
181 // We'll do this lookup again later.
182 R.suppressDiagnostics();
184 assert(isa<ClassTemplateDecl>(TD) || isa<TemplateTemplateParmDecl>(TD));
185 TemplateKind = TNK_Type_template;
189 TemplateResult = TemplateTy::make(Template);
193 bool Sema::DiagnoseUnknownTemplateName(const IdentifierInfo &II,
194 SourceLocation IILoc,
196 const CXXScopeSpec *SS,
197 TemplateTy &SuggestedTemplate,
198 TemplateNameKind &SuggestedKind) {
199 // We can't recover unless there's a dependent scope specifier preceding the
201 // FIXME: Typo correction?
202 if (!SS || !SS->isSet() || !isDependentScopeSpecifier(*SS) ||
203 computeDeclContext(*SS))
206 // The code is missing a 'template' keyword prior to the dependent template
208 NestedNameSpecifier *Qualifier = (NestedNameSpecifier*)SS->getScopeRep();
209 Diag(IILoc, diag::err_template_kw_missing)
210 << Qualifier << II.getName()
211 << FixItHint::CreateInsertion(IILoc, "template ");
213 = TemplateTy::make(Context.getDependentTemplateName(Qualifier, &II));
214 SuggestedKind = TNK_Dependent_template_name;
218 void Sema::LookupTemplateName(LookupResult &Found,
219 Scope *S, CXXScopeSpec &SS,
221 bool EnteringContext,
222 bool &MemberOfUnknownSpecialization) {
223 // Determine where to perform name lookup
224 MemberOfUnknownSpecialization = false;
225 DeclContext *LookupCtx = 0;
226 bool isDependent = false;
227 if (!ObjectType.isNull()) {
228 // This nested-name-specifier occurs in a member access expression, e.g.,
229 // x->B::f, and we are looking into the type of the object.
230 assert(!SS.isSet() && "ObjectType and scope specifier cannot coexist");
231 LookupCtx = computeDeclContext(ObjectType);
232 isDependent = ObjectType->isDependentType();
233 assert((isDependent || !ObjectType->isIncompleteType()) &&
234 "Caller should have completed object type");
235 } else if (SS.isSet()) {
236 // This nested-name-specifier occurs after another nested-name-specifier,
237 // so long into the context associated with the prior nested-name-specifier.
238 LookupCtx = computeDeclContext(SS, EnteringContext);
239 isDependent = isDependentScopeSpecifier(SS);
241 // The declaration context must be complete.
242 if (LookupCtx && RequireCompleteDeclContext(SS, LookupCtx))
246 bool ObjectTypeSearchedInScope = false;
248 // Perform "qualified" name lookup into the declaration context we
249 // computed, which is either the type of the base of a member access
250 // expression or the declaration context associated with a prior
251 // nested-name-specifier.
252 LookupQualifiedName(Found, LookupCtx);
254 if (!ObjectType.isNull() && Found.empty()) {
255 // C++ [basic.lookup.classref]p1:
256 // In a class member access expression (5.2.5), if the . or -> token is
257 // immediately followed by an identifier followed by a <, the
258 // identifier must be looked up to determine whether the < is the
259 // beginning of a template argument list (14.2) or a less-than operator.
260 // The identifier is first looked up in the class of the object
261 // expression. If the identifier is not found, it is then looked up in
262 // the context of the entire postfix-expression and shall name a class
263 // or function template.
264 if (S) LookupName(Found, S);
265 ObjectTypeSearchedInScope = true;
267 } else if (isDependent && (!S || ObjectType.isNull())) {
268 // We cannot look into a dependent object type or nested nme
270 MemberOfUnknownSpecialization = true;
273 // Perform unqualified name lookup in the current scope.
274 LookupName(Found, S);
277 if (Found.empty() && !isDependent) {
278 // If we did not find any names, attempt to correct any typos.
279 DeclarationName Name = Found.getLookupName();
280 if (DeclarationName Corrected = CorrectTypo(Found, S, &SS, LookupCtx,
281 false, CTC_CXXCasts)) {
282 FilterAcceptableTemplateNames(Context, Found);
283 if (!Found.empty()) {
285 Diag(Found.getNameLoc(), diag::err_no_member_template_suggest)
286 << Name << LookupCtx << Found.getLookupName() << SS.getRange()
287 << FixItHint::CreateReplacement(Found.getNameLoc(),
288 Found.getLookupName().getAsString());
290 Diag(Found.getNameLoc(), diag::err_no_template_suggest)
291 << Name << Found.getLookupName()
292 << FixItHint::CreateReplacement(Found.getNameLoc(),
293 Found.getLookupName().getAsString());
294 if (TemplateDecl *Template = Found.getAsSingle<TemplateDecl>())
295 Diag(Template->getLocation(), diag::note_previous_decl)
296 << Template->getDeclName();
300 Found.setLookupName(Name);
304 FilterAcceptableTemplateNames(Context, Found);
307 MemberOfUnknownSpecialization = true;
311 if (S && !ObjectType.isNull() && !ObjectTypeSearchedInScope) {
312 // C++ [basic.lookup.classref]p1:
313 // [...] If the lookup in the class of the object expression finds a
314 // template, the name is also looked up in the context of the entire
315 // postfix-expression and [...]
317 LookupResult FoundOuter(*this, Found.getLookupName(), Found.getNameLoc(),
319 LookupName(FoundOuter, S);
320 FilterAcceptableTemplateNames(Context, FoundOuter);
322 if (FoundOuter.empty()) {
323 // - if the name is not found, the name found in the class of the
324 // object expression is used, otherwise
325 } else if (!FoundOuter.getAsSingle<ClassTemplateDecl>()) {
326 // - if the name is found in the context of the entire
327 // postfix-expression and does not name a class template, the name
328 // found in the class of the object expression is used, otherwise
329 } else if (!Found.isSuppressingDiagnostics()) {
330 // - if the name found is a class template, it must refer to the same
331 // entity as the one found in the class of the object expression,
332 // otherwise the program is ill-formed.
333 if (!Found.isSingleResult() ||
334 Found.getFoundDecl()->getCanonicalDecl()
335 != FoundOuter.getFoundDecl()->getCanonicalDecl()) {
336 Diag(Found.getNameLoc(),
337 diag::ext_nested_name_member_ref_lookup_ambiguous)
338 << Found.getLookupName()
340 Diag(Found.getRepresentativeDecl()->getLocation(),
341 diag::note_ambig_member_ref_object_type)
343 Diag(FoundOuter.getFoundDecl()->getLocation(),
344 diag::note_ambig_member_ref_scope);
346 // Recover by taking the template that we found in the object
347 // expression's type.
353 /// ActOnDependentIdExpression - Handle a dependent id-expression that
354 /// was just parsed. This is only possible with an explicit scope
355 /// specifier naming a dependent type.
357 Sema::ActOnDependentIdExpression(const CXXScopeSpec &SS,
358 const DeclarationNameInfo &NameInfo,
359 bool isAddressOfOperand,
360 const TemplateArgumentListInfo *TemplateArgs) {
361 NestedNameSpecifier *Qualifier
362 = static_cast<NestedNameSpecifier*>(SS.getScopeRep());
364 DeclContext *DC = getFunctionLevelDeclContext();
366 if (!isAddressOfOperand &&
367 isa<CXXMethodDecl>(DC) &&
368 cast<CXXMethodDecl>(DC)->isInstance()) {
369 QualType ThisType = cast<CXXMethodDecl>(DC)->getThisType(Context);
371 // Since the 'this' expression is synthesized, we don't need to
372 // perform the double-lookup check.
373 NamedDecl *FirstQualifierInScope = 0;
375 return Owned(CXXDependentScopeMemberExpr::Create(Context,
376 /*This*/ 0, ThisType,
378 /*Op*/ SourceLocation(),
379 Qualifier, SS.getRange(),
380 FirstQualifierInScope,
385 return BuildDependentDeclRefExpr(SS, NameInfo, TemplateArgs);
389 Sema::BuildDependentDeclRefExpr(const CXXScopeSpec &SS,
390 const DeclarationNameInfo &NameInfo,
391 const TemplateArgumentListInfo *TemplateArgs) {
392 return Owned(DependentScopeDeclRefExpr::Create(Context,
393 static_cast<NestedNameSpecifier*>(SS.getScopeRep()),
399 /// DiagnoseTemplateParameterShadow - Produce a diagnostic complaining
400 /// that the template parameter 'PrevDecl' is being shadowed by a new
401 /// declaration at location Loc. Returns true to indicate that this is
402 /// an error, and false otherwise.
403 bool Sema::DiagnoseTemplateParameterShadow(SourceLocation Loc, Decl *PrevDecl) {
404 assert(PrevDecl->isTemplateParameter() && "Not a template parameter");
406 // Microsoft Visual C++ permits template parameters to be shadowed.
407 if (getLangOptions().Microsoft)
410 // C++ [temp.local]p4:
411 // A template-parameter shall not be redeclared within its
412 // scope (including nested scopes).
413 Diag(Loc, diag::err_template_param_shadow)
414 << cast<NamedDecl>(PrevDecl)->getDeclName();
415 Diag(PrevDecl->getLocation(), diag::note_template_param_here);
419 /// AdjustDeclIfTemplate - If the given decl happens to be a template, reset
420 /// the parameter D to reference the templated declaration and return a pointer
421 /// to the template declaration. Otherwise, do nothing to D and return null.
422 TemplateDecl *Sema::AdjustDeclIfTemplate(Decl *&D) {
423 if (TemplateDecl *Temp = dyn_cast_or_null<TemplateDecl>(D)) {
424 D = Temp->getTemplatedDecl();
430 static TemplateArgumentLoc translateTemplateArgument(Sema &SemaRef,
431 const ParsedTemplateArgument &Arg) {
433 switch (Arg.getKind()) {
434 case ParsedTemplateArgument::Type: {
436 QualType T = SemaRef.GetTypeFromParser(Arg.getAsType(), &DI);
438 DI = SemaRef.Context.getTrivialTypeSourceInfo(T, Arg.getLocation());
439 return TemplateArgumentLoc(TemplateArgument(T), DI);
442 case ParsedTemplateArgument::NonType: {
443 Expr *E = static_cast<Expr *>(Arg.getAsExpr());
444 return TemplateArgumentLoc(TemplateArgument(E), E);
447 case ParsedTemplateArgument::Template: {
448 TemplateName Template = Arg.getAsTemplate().get();
449 return TemplateArgumentLoc(TemplateArgument(Template),
450 Arg.getScopeSpec().getRange(),
455 llvm_unreachable("Unhandled parsed template argument");
456 return TemplateArgumentLoc();
459 /// \brief Translates template arguments as provided by the parser
460 /// into template arguments used by semantic analysis.
461 void Sema::translateTemplateArguments(const ASTTemplateArgsPtr &TemplateArgsIn,
462 TemplateArgumentListInfo &TemplateArgs) {
463 for (unsigned I = 0, Last = TemplateArgsIn.size(); I != Last; ++I)
464 TemplateArgs.addArgument(translateTemplateArgument(*this,
468 /// ActOnTypeParameter - Called when a C++ template type parameter
469 /// (e.g., "typename T") has been parsed. Typename specifies whether
470 /// the keyword "typename" was used to declare the type parameter
471 /// (otherwise, "class" was used), and KeyLoc is the location of the
472 /// "class" or "typename" keyword. ParamName is the name of the
473 /// parameter (NULL indicates an unnamed template parameter) and
474 /// ParamName is the location of the parameter name (if any).
475 /// If the type parameter has a default argument, it will be added
476 /// later via ActOnTypeParameterDefault.
477 Decl *Sema::ActOnTypeParameter(Scope *S, bool Typename, bool Ellipsis,
478 SourceLocation EllipsisLoc,
479 SourceLocation KeyLoc,
480 IdentifierInfo *ParamName,
481 SourceLocation ParamNameLoc,
482 unsigned Depth, unsigned Position,
483 SourceLocation EqualLoc,
484 ParsedType DefaultArg) {
485 assert(S->isTemplateParamScope() &&
486 "Template type parameter not in template parameter scope!");
487 bool Invalid = false;
490 NamedDecl *PrevDecl = LookupSingleName(S, ParamName, ParamNameLoc,
493 if (PrevDecl && PrevDecl->isTemplateParameter())
494 Invalid = Invalid || DiagnoseTemplateParameterShadow(ParamNameLoc,
498 SourceLocation Loc = ParamNameLoc;
502 TemplateTypeParmDecl *Param
503 = TemplateTypeParmDecl::Create(Context, Context.getTranslationUnitDecl(),
504 Loc, Depth, Position, ParamName, Typename,
507 Param->setInvalidDecl();
510 // Add the template parameter into the current scope.
512 IdResolver.AddDecl(Param);
515 // Handle the default argument, if provided.
517 TypeSourceInfo *DefaultTInfo;
518 GetTypeFromParser(DefaultArg, &DefaultTInfo);
520 assert(DefaultTInfo && "expected source information for type");
522 // C++0x [temp.param]p9:
523 // A default template-argument may be specified for any kind of
524 // template-parameter that is not a template parameter pack.
526 Diag(EqualLoc, diag::err_template_param_pack_default_arg);
530 // Check the template argument itself.
531 if (CheckTemplateArgument(Param, DefaultTInfo)) {
532 Param->setInvalidDecl();
536 Param->setDefaultArgument(DefaultTInfo, false);
542 /// \brief Check that the type of a non-type template parameter is
545 /// \returns the (possibly-promoted) parameter type if valid;
546 /// otherwise, produces a diagnostic and returns a NULL type.
548 Sema::CheckNonTypeTemplateParameterType(QualType T, SourceLocation Loc) {
549 // We don't allow variably-modified types as the type of non-type template
551 if (T->isVariablyModifiedType()) {
552 Diag(Loc, diag::err_variably_modified_nontype_template_param)
557 // C++ [temp.param]p4:
559 // A non-type template-parameter shall have one of the following
560 // (optionally cv-qualified) types:
562 // -- integral or enumeration type,
563 if (T->isIntegralOrEnumerationType() ||
564 // -- pointer to object or pointer to function,
565 T->isPointerType() ||
566 // -- reference to object or reference to function,
567 T->isReferenceType() ||
568 // -- pointer to member.
569 T->isMemberPointerType() ||
570 // If T is a dependent type, we can't do the check now, so we
571 // assume that it is well-formed.
572 T->isDependentType())
574 // C++ [temp.param]p8:
576 // A non-type template-parameter of type "array of T" or
577 // "function returning T" is adjusted to be of type "pointer to
578 // T" or "pointer to function returning T", respectively.
579 else if (T->isArrayType())
580 // FIXME: Keep the type prior to promotion?
581 return Context.getArrayDecayedType(T);
582 else if (T->isFunctionType())
583 // FIXME: Keep the type prior to promotion?
584 return Context.getPointerType(T);
586 Diag(Loc, diag::err_template_nontype_parm_bad_type)
592 Decl *Sema::ActOnNonTypeTemplateParameter(Scope *S, Declarator &D,
595 SourceLocation EqualLoc,
597 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S);
598 QualType T = TInfo->getType();
600 assert(S->isTemplateParamScope() &&
601 "Non-type template parameter not in template parameter scope!");
602 bool Invalid = false;
604 IdentifierInfo *ParamName = D.getIdentifier();
606 NamedDecl *PrevDecl = LookupSingleName(S, ParamName, D.getIdentifierLoc(),
609 if (PrevDecl && PrevDecl->isTemplateParameter())
610 Invalid = Invalid || DiagnoseTemplateParameterShadow(D.getIdentifierLoc(),
614 T = CheckNonTypeTemplateParameterType(T, D.getIdentifierLoc());
616 T = Context.IntTy; // Recover with an 'int' type.
620 NonTypeTemplateParmDecl *Param
621 = NonTypeTemplateParmDecl::Create(Context, Context.getTranslationUnitDecl(),
622 D.getIdentifierLoc(),
623 Depth, Position, ParamName, T, TInfo);
625 Param->setInvalidDecl();
627 if (D.getIdentifier()) {
628 // Add the template parameter into the current scope.
630 IdResolver.AddDecl(Param);
633 // Check the well-formedness of the default template argument, if provided.
635 TemplateArgument Converted;
636 if (CheckTemplateArgument(Param, Param->getType(), Default, Converted)) {
637 Param->setInvalidDecl();
641 Param->setDefaultArgument(Default, false);
647 /// ActOnTemplateTemplateParameter - Called when a C++ template template
648 /// parameter (e.g. T in template <template <typename> class T> class array)
649 /// has been parsed. S is the current scope.
650 Decl *Sema::ActOnTemplateTemplateParameter(Scope* S,
651 SourceLocation TmpLoc,
652 TemplateParamsTy *Params,
653 IdentifierInfo *Name,
654 SourceLocation NameLoc,
657 SourceLocation EqualLoc,
658 const ParsedTemplateArgument &Default) {
659 assert(S->isTemplateParamScope() &&
660 "Template template parameter not in template parameter scope!");
662 // Construct the parameter object.
663 TemplateTemplateParmDecl *Param =
664 TemplateTemplateParmDecl::Create(Context, Context.getTranslationUnitDecl(),
665 NameLoc.isInvalid()? TmpLoc : NameLoc,
666 Depth, Position, Name,
667 (TemplateParameterList*)Params);
669 // If the template template parameter has a name, then link the identifier
670 // into the scope and lookup mechanisms.
673 IdResolver.AddDecl(Param);
676 if (!Default.isInvalid()) {
677 // Check only that we have a template template argument. We don't want to
678 // try to check well-formedness now, because our template template parameter
679 // might have dependent types in its template parameters, which we wouldn't
680 // be able to match now.
682 // If none of the template template parameter's template arguments mention
683 // other template parameters, we could actually perform more checking here.
684 // However, it isn't worth doing.
685 TemplateArgumentLoc DefaultArg = translateTemplateArgument(*this, Default);
686 if (DefaultArg.getArgument().getAsTemplate().isNull()) {
687 Diag(DefaultArg.getLocation(), diag::err_template_arg_not_class_template)
688 << DefaultArg.getSourceRange();
692 Param->setDefaultArgument(DefaultArg, false);
698 /// ActOnTemplateParameterList - Builds a TemplateParameterList that
699 /// contains the template parameters in Params/NumParams.
700 Sema::TemplateParamsTy *
701 Sema::ActOnTemplateParameterList(unsigned Depth,
702 SourceLocation ExportLoc,
703 SourceLocation TemplateLoc,
704 SourceLocation LAngleLoc,
705 Decl **Params, unsigned NumParams,
706 SourceLocation RAngleLoc) {
707 if (ExportLoc.isValid())
708 Diag(ExportLoc, diag::warn_template_export_unsupported);
710 return TemplateParameterList::Create(Context, TemplateLoc, LAngleLoc,
711 (NamedDecl**)Params, NumParams,
715 static void SetNestedNameSpecifier(TagDecl *T, const CXXScopeSpec &SS) {
717 T->setQualifierInfo(static_cast<NestedNameSpecifier*>(SS.getScopeRep()),
722 Sema::CheckClassTemplate(Scope *S, unsigned TagSpec, TagUseKind TUK,
723 SourceLocation KWLoc, CXXScopeSpec &SS,
724 IdentifierInfo *Name, SourceLocation NameLoc,
726 TemplateParameterList *TemplateParams,
727 AccessSpecifier AS) {
728 assert(TemplateParams && TemplateParams->size() > 0 &&
729 "No template parameters");
730 assert(TUK != TUK_Reference && "Can only declare or define class templates");
731 bool Invalid = false;
733 // Check that we can declare a template here.
734 if (CheckTemplateDeclScope(S, TemplateParams))
737 TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec);
738 assert(Kind != TTK_Enum && "can't build template of enumerated type");
740 // There is no such thing as an unnamed class template.
742 Diag(KWLoc, diag::err_template_unnamed_class);
746 // Find any previous declaration with this name.
747 DeclContext *SemanticContext;
748 LookupResult Previous(*this, Name, NameLoc, LookupOrdinaryName,
750 if (SS.isNotEmpty() && !SS.isInvalid()) {
751 SemanticContext = computeDeclContext(SS, true);
752 if (!SemanticContext) {
753 // FIXME: Produce a reasonable diagnostic here
757 if (RequireCompleteDeclContext(SS, SemanticContext))
760 LookupQualifiedName(Previous, SemanticContext);
762 SemanticContext = CurContext;
763 LookupName(Previous, S);
766 if (Previous.isAmbiguous())
769 NamedDecl *PrevDecl = 0;
770 if (Previous.begin() != Previous.end())
771 PrevDecl = (*Previous.begin())->getUnderlyingDecl();
773 // If there is a previous declaration with the same name, check
774 // whether this is a valid redeclaration.
775 ClassTemplateDecl *PrevClassTemplate
776 = dyn_cast_or_null<ClassTemplateDecl>(PrevDecl);
778 // We may have found the injected-class-name of a class template,
779 // class template partial specialization, or class template specialization.
780 // In these cases, grab the template that is being defined or specialized.
781 if (!PrevClassTemplate && PrevDecl && isa<CXXRecordDecl>(PrevDecl) &&
782 cast<CXXRecordDecl>(PrevDecl)->isInjectedClassName()) {
783 PrevDecl = cast<CXXRecordDecl>(PrevDecl->getDeclContext());
785 = cast<CXXRecordDecl>(PrevDecl)->getDescribedClassTemplate();
786 if (!PrevClassTemplate && isa<ClassTemplateSpecializationDecl>(PrevDecl)) {
788 = cast<ClassTemplateSpecializationDecl>(PrevDecl)
789 ->getSpecializedTemplate();
793 if (TUK == TUK_Friend) {
794 // C++ [namespace.memdef]p3:
795 // [...] When looking for a prior declaration of a class or a function
796 // declared as a friend, and when the name of the friend class or
797 // function is neither a qualified name nor a template-id, scopes outside
798 // the innermost enclosing namespace scope are not considered.
800 DeclContext *OutermostContext = CurContext;
801 while (!OutermostContext->isFileContext())
802 OutermostContext = OutermostContext->getLookupParent();
805 (OutermostContext->Equals(PrevDecl->getDeclContext()) ||
806 OutermostContext->Encloses(PrevDecl->getDeclContext()))) {
807 SemanticContext = PrevDecl->getDeclContext();
809 // Declarations in outer scopes don't matter. However, the outermost
810 // context we computed is the semantic context for our new
812 PrevDecl = PrevClassTemplate = 0;
813 SemanticContext = OutermostContext;
817 if (CurContext->isDependentContext()) {
818 // If this is a dependent context, we don't want to link the friend
819 // class template to the template in scope, because that would perform
820 // checking of the template parameter lists that can't be performed
821 // until the outer context is instantiated.
822 PrevDecl = PrevClassTemplate = 0;
824 } else if (PrevDecl && !isDeclInScope(PrevDecl, SemanticContext, S))
825 PrevDecl = PrevClassTemplate = 0;
827 if (PrevClassTemplate) {
828 // Ensure that the template parameter lists are compatible.
829 if (!TemplateParameterListsAreEqual(TemplateParams,
830 PrevClassTemplate->getTemplateParameters(),
835 // C++ [temp.class]p4:
836 // In a redeclaration, partial specialization, explicit
837 // specialization or explicit instantiation of a class template,
838 // the class-key shall agree in kind with the original class
839 // template declaration (7.1.5.3).
840 RecordDecl *PrevRecordDecl = PrevClassTemplate->getTemplatedDecl();
841 if (!isAcceptableTagRedeclaration(PrevRecordDecl, Kind, KWLoc, *Name)) {
842 Diag(KWLoc, diag::err_use_with_wrong_tag)
844 << FixItHint::CreateReplacement(KWLoc, PrevRecordDecl->getKindName());
845 Diag(PrevRecordDecl->getLocation(), diag::note_previous_use);
846 Kind = PrevRecordDecl->getTagKind();
849 // Check for redefinition of this class template.
850 if (TUK == TUK_Definition) {
851 if (TagDecl *Def = PrevRecordDecl->getDefinition()) {
852 Diag(NameLoc, diag::err_redefinition) << Name;
853 Diag(Def->getLocation(), diag::note_previous_definition);
854 // FIXME: Would it make sense to try to "forget" the previous
855 // definition, as part of error recovery?
859 } else if (PrevDecl && PrevDecl->isTemplateParameter()) {
860 // Maybe we will complain about the shadowed template parameter.
861 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl);
862 // Just pretend that we didn't see the previous declaration.
864 } else if (PrevDecl) {
866 // A class template shall not have the same name as any other
867 // template, class, function, object, enumeration, enumerator,
868 // namespace, or type in the same scope (3.3), except as specified
870 Diag(NameLoc, diag::err_redefinition_different_kind) << Name;
871 Diag(PrevDecl->getLocation(), diag::note_previous_definition);
875 // Check the template parameter list of this declaration, possibly
876 // merging in the template parameter list from the previous class
877 // template declaration.
878 if (CheckTemplateParameterList(TemplateParams,
879 PrevClassTemplate? PrevClassTemplate->getTemplateParameters() : 0,
884 // If the name of the template was qualified, we must be defining the
885 // template out-of-line.
886 if (!SS.isInvalid() && !Invalid && !PrevClassTemplate &&
887 !(TUK == TUK_Friend && CurContext->isDependentContext()))
888 Diag(NameLoc, diag::err_member_def_does_not_match)
889 << Name << SemanticContext << SS.getRange();
892 CXXRecordDecl *NewClass =
893 CXXRecordDecl::Create(Context, Kind, SemanticContext, NameLoc, Name, KWLoc,
895 PrevClassTemplate->getTemplatedDecl() : 0,
896 /*DelayTypeCreation=*/true);
897 SetNestedNameSpecifier(NewClass, SS);
899 ClassTemplateDecl *NewTemplate
900 = ClassTemplateDecl::Create(Context, SemanticContext, NameLoc,
901 DeclarationName(Name), TemplateParams,
902 NewClass, PrevClassTemplate);
903 NewClass->setDescribedClassTemplate(NewTemplate);
905 // Build the type for the class template declaration now.
906 QualType T = NewTemplate->getInjectedClassNameSpecialization();
907 T = Context.getInjectedClassNameType(NewClass, T);
908 assert(T->isDependentType() && "Class template type is not dependent?");
911 // If we are providing an explicit specialization of a member that is a
912 // class template, make a note of that.
913 if (PrevClassTemplate &&
914 PrevClassTemplate->getInstantiatedFromMemberTemplate())
915 PrevClassTemplate->setMemberSpecialization();
917 // Set the access specifier.
918 if (!Invalid && TUK != TUK_Friend)
919 SetMemberAccessSpecifier(NewTemplate, PrevClassTemplate, AS);
921 // Set the lexical context of these templates
922 NewClass->setLexicalDeclContext(CurContext);
923 NewTemplate->setLexicalDeclContext(CurContext);
925 if (TUK == TUK_Definition)
926 NewClass->startDefinition();
929 ProcessDeclAttributeList(S, NewClass, Attr);
931 if (TUK != TUK_Friend)
932 PushOnScopeChains(NewTemplate, S);
934 if (PrevClassTemplate && PrevClassTemplate->getAccess() != AS_none) {
935 NewTemplate->setAccess(PrevClassTemplate->getAccess());
936 NewClass->setAccess(PrevClassTemplate->getAccess());
939 NewTemplate->setObjectOfFriendDecl(/* PreviouslyDeclared = */
940 PrevClassTemplate != NULL);
942 // Friend templates are visible in fairly strange ways.
943 if (!CurContext->isDependentContext()) {
944 DeclContext *DC = SemanticContext->getRedeclContext();
945 DC->makeDeclVisibleInContext(NewTemplate, /* Recoverable = */ false);
946 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC))
947 PushOnScopeChains(NewTemplate, EnclosingScope,
948 /* AddToContext = */ false);
951 FriendDecl *Friend = FriendDecl::Create(Context, CurContext,
952 NewClass->getLocation(),
954 /*FIXME:*/NewClass->getLocation());
955 Friend->setAccess(AS_public);
956 CurContext->addDecl(Friend);
960 NewTemplate->setInvalidDecl();
961 NewClass->setInvalidDecl();
966 /// \brief Diagnose the presence of a default template argument on a
967 /// template parameter, which is ill-formed in certain contexts.
969 /// \returns true if the default template argument should be dropped.
970 static bool DiagnoseDefaultTemplateArgument(Sema &S,
971 Sema::TemplateParamListContext TPC,
972 SourceLocation ParamLoc,
973 SourceRange DefArgRange) {
975 case Sema::TPC_ClassTemplate:
978 case Sema::TPC_FunctionTemplate:
979 // C++ [temp.param]p9:
980 // A default template-argument shall not be specified in a
981 // function template declaration or a function template
983 // (This sentence is not in C++0x, per DR226).
984 if (!S.getLangOptions().CPlusPlus0x)
986 diag::err_template_parameter_default_in_function_template)
990 case Sema::TPC_ClassTemplateMember:
991 // C++0x [temp.param]p9:
992 // A default template-argument shall not be specified in the
993 // template-parameter-lists of the definition of a member of a
994 // class template that appears outside of the member's class.
995 S.Diag(ParamLoc, diag::err_template_parameter_default_template_member)
999 case Sema::TPC_FriendFunctionTemplate:
1000 // C++ [temp.param]p9:
1001 // A default template-argument shall not be specified in a
1002 // friend template declaration.
1003 S.Diag(ParamLoc, diag::err_template_parameter_default_friend_template)
1007 // FIXME: C++0x [temp.param]p9 allows default template-arguments
1008 // for friend function templates if there is only a single
1009 // declaration (and it is a definition). Strange!
1015 /// \brief Checks the validity of a template parameter list, possibly
1016 /// considering the template parameter list from a previous
1019 /// If an "old" template parameter list is provided, it must be
1020 /// equivalent (per TemplateParameterListsAreEqual) to the "new"
1021 /// template parameter list.
1023 /// \param NewParams Template parameter list for a new template
1024 /// declaration. This template parameter list will be updated with any
1025 /// default arguments that are carried through from the previous
1026 /// template parameter list.
1028 /// \param OldParams If provided, template parameter list from a
1029 /// previous declaration of the same template. Default template
1030 /// arguments will be merged from the old template parameter list to
1031 /// the new template parameter list.
1033 /// \param TPC Describes the context in which we are checking the given
1034 /// template parameter list.
1036 /// \returns true if an error occurred, false otherwise.
1037 bool Sema::CheckTemplateParameterList(TemplateParameterList *NewParams,
1038 TemplateParameterList *OldParams,
1039 TemplateParamListContext TPC) {
1040 bool Invalid = false;
1042 // C++ [temp.param]p10:
1043 // The set of default template-arguments available for use with a
1044 // template declaration or definition is obtained by merging the
1045 // default arguments from the definition (if in scope) and all
1046 // declarations in scope in the same way default function
1047 // arguments are (8.3.6).
1048 bool SawDefaultArgument = false;
1049 SourceLocation PreviousDefaultArgLoc;
1051 bool SawParameterPack = false;
1052 SourceLocation ParameterPackLoc;
1054 // Dummy initialization to avoid warnings.
1055 TemplateParameterList::iterator OldParam = NewParams->end();
1057 OldParam = OldParams->begin();
1059 for (TemplateParameterList::iterator NewParam = NewParams->begin(),
1060 NewParamEnd = NewParams->end();
1061 NewParam != NewParamEnd; ++NewParam) {
1062 // Variables used to diagnose redundant default arguments
1063 bool RedundantDefaultArg = false;
1064 SourceLocation OldDefaultLoc;
1065 SourceLocation NewDefaultLoc;
1067 // Variables used to diagnose missing default arguments
1068 bool MissingDefaultArg = false;
1070 // C++0x [temp.param]p11:
1071 // If a template parameter of a class template is a template parameter pack,
1072 // it must be the last template parameter.
1073 if (SawParameterPack) {
1074 Diag(ParameterPackLoc,
1075 diag::err_template_param_pack_must_be_last_template_parameter);
1079 if (TemplateTypeParmDecl *NewTypeParm
1080 = dyn_cast<TemplateTypeParmDecl>(*NewParam)) {
1081 // Check the presence of a default argument here.
1082 if (NewTypeParm->hasDefaultArgument() &&
1083 DiagnoseDefaultTemplateArgument(*this, TPC,
1084 NewTypeParm->getLocation(),
1085 NewTypeParm->getDefaultArgumentInfo()->getTypeLoc()
1087 NewTypeParm->removeDefaultArgument();
1089 // Merge default arguments for template type parameters.
1090 TemplateTypeParmDecl *OldTypeParm
1091 = OldParams? cast<TemplateTypeParmDecl>(*OldParam) : 0;
1093 if (NewTypeParm->isParameterPack()) {
1094 assert(!NewTypeParm->hasDefaultArgument() &&
1095 "Parameter packs can't have a default argument!");
1096 SawParameterPack = true;
1097 ParameterPackLoc = NewTypeParm->getLocation();
1098 } else if (OldTypeParm && OldTypeParm->hasDefaultArgument() &&
1099 NewTypeParm->hasDefaultArgument()) {
1100 OldDefaultLoc = OldTypeParm->getDefaultArgumentLoc();
1101 NewDefaultLoc = NewTypeParm->getDefaultArgumentLoc();
1102 SawDefaultArgument = true;
1103 RedundantDefaultArg = true;
1104 PreviousDefaultArgLoc = NewDefaultLoc;
1105 } else if (OldTypeParm && OldTypeParm->hasDefaultArgument()) {
1106 // Merge the default argument from the old declaration to the
1108 SawDefaultArgument = true;
1109 NewTypeParm->setDefaultArgument(OldTypeParm->getDefaultArgumentInfo(),
1111 PreviousDefaultArgLoc = OldTypeParm->getDefaultArgumentLoc();
1112 } else if (NewTypeParm->hasDefaultArgument()) {
1113 SawDefaultArgument = true;
1114 PreviousDefaultArgLoc = NewTypeParm->getDefaultArgumentLoc();
1115 } else if (SawDefaultArgument)
1116 MissingDefaultArg = true;
1117 } else if (NonTypeTemplateParmDecl *NewNonTypeParm
1118 = dyn_cast<NonTypeTemplateParmDecl>(*NewParam)) {
1119 // Check the presence of a default argument here.
1120 if (NewNonTypeParm->hasDefaultArgument() &&
1121 DiagnoseDefaultTemplateArgument(*this, TPC,
1122 NewNonTypeParm->getLocation(),
1123 NewNonTypeParm->getDefaultArgument()->getSourceRange())) {
1124 NewNonTypeParm->removeDefaultArgument();
1127 // Merge default arguments for non-type template parameters
1128 NonTypeTemplateParmDecl *OldNonTypeParm
1129 = OldParams? cast<NonTypeTemplateParmDecl>(*OldParam) : 0;
1130 if (OldNonTypeParm && OldNonTypeParm->hasDefaultArgument() &&
1131 NewNonTypeParm->hasDefaultArgument()) {
1132 OldDefaultLoc = OldNonTypeParm->getDefaultArgumentLoc();
1133 NewDefaultLoc = NewNonTypeParm->getDefaultArgumentLoc();
1134 SawDefaultArgument = true;
1135 RedundantDefaultArg = true;
1136 PreviousDefaultArgLoc = NewDefaultLoc;
1137 } else if (OldNonTypeParm && OldNonTypeParm->hasDefaultArgument()) {
1138 // Merge the default argument from the old declaration to the
1140 SawDefaultArgument = true;
1141 // FIXME: We need to create a new kind of "default argument"
1142 // expression that points to a previous template template
1144 NewNonTypeParm->setDefaultArgument(
1145 OldNonTypeParm->getDefaultArgument(),
1146 /*Inherited=*/ true);
1147 PreviousDefaultArgLoc = OldNonTypeParm->getDefaultArgumentLoc();
1148 } else if (NewNonTypeParm->hasDefaultArgument()) {
1149 SawDefaultArgument = true;
1150 PreviousDefaultArgLoc = NewNonTypeParm->getDefaultArgumentLoc();
1151 } else if (SawDefaultArgument)
1152 MissingDefaultArg = true;
1154 // Check the presence of a default argument here.
1155 TemplateTemplateParmDecl *NewTemplateParm
1156 = cast<TemplateTemplateParmDecl>(*NewParam);
1157 if (NewTemplateParm->hasDefaultArgument() &&
1158 DiagnoseDefaultTemplateArgument(*this, TPC,
1159 NewTemplateParm->getLocation(),
1160 NewTemplateParm->getDefaultArgument().getSourceRange()))
1161 NewTemplateParm->removeDefaultArgument();
1163 // Merge default arguments for template template parameters
1164 TemplateTemplateParmDecl *OldTemplateParm
1165 = OldParams? cast<TemplateTemplateParmDecl>(*OldParam) : 0;
1166 if (OldTemplateParm && OldTemplateParm->hasDefaultArgument() &&
1167 NewTemplateParm->hasDefaultArgument()) {
1168 OldDefaultLoc = OldTemplateParm->getDefaultArgument().getLocation();
1169 NewDefaultLoc = NewTemplateParm->getDefaultArgument().getLocation();
1170 SawDefaultArgument = true;
1171 RedundantDefaultArg = true;
1172 PreviousDefaultArgLoc = NewDefaultLoc;
1173 } else if (OldTemplateParm && OldTemplateParm->hasDefaultArgument()) {
1174 // Merge the default argument from the old declaration to the
1176 SawDefaultArgument = true;
1177 // FIXME: We need to create a new kind of "default argument" expression
1178 // that points to a previous template template parameter.
1179 NewTemplateParm->setDefaultArgument(
1180 OldTemplateParm->getDefaultArgument(),
1181 /*Inherited=*/ true);
1182 PreviousDefaultArgLoc
1183 = OldTemplateParm->getDefaultArgument().getLocation();
1184 } else if (NewTemplateParm->hasDefaultArgument()) {
1185 SawDefaultArgument = true;
1186 PreviousDefaultArgLoc
1187 = NewTemplateParm->getDefaultArgument().getLocation();
1188 } else if (SawDefaultArgument)
1189 MissingDefaultArg = true;
1192 if (RedundantDefaultArg) {
1193 // C++ [temp.param]p12:
1194 // A template-parameter shall not be given default arguments
1195 // by two different declarations in the same scope.
1196 Diag(NewDefaultLoc, diag::err_template_param_default_arg_redefinition);
1197 Diag(OldDefaultLoc, diag::note_template_param_prev_default_arg);
1199 } else if (MissingDefaultArg) {
1200 // C++ [temp.param]p11:
1201 // If a template-parameter has a default template-argument,
1202 // all subsequent template-parameters shall have a default
1203 // template-argument supplied.
1204 Diag((*NewParam)->getLocation(),
1205 diag::err_template_param_default_arg_missing);
1206 Diag(PreviousDefaultArgLoc, diag::note_template_param_prev_default_arg);
1210 // If we have an old template parameter list that we're merging
1211 // in, move on to the next parameter.
1219 /// \brief Match the given template parameter lists to the given scope
1220 /// specifier, returning the template parameter list that applies to the
1223 /// \param DeclStartLoc the start of the declaration that has a scope
1224 /// specifier or a template parameter list.
1226 /// \param SS the scope specifier that will be matched to the given template
1227 /// parameter lists. This scope specifier precedes a qualified name that is
1230 /// \param ParamLists the template parameter lists, from the outermost to the
1231 /// innermost template parameter lists.
1233 /// \param NumParamLists the number of template parameter lists in ParamLists.
1235 /// \param IsFriend Whether to apply the slightly different rules for
1236 /// matching template parameters to scope specifiers in friend
1239 /// \param IsExplicitSpecialization will be set true if the entity being
1240 /// declared is an explicit specialization, false otherwise.
1242 /// \returns the template parameter list, if any, that corresponds to the
1243 /// name that is preceded by the scope specifier @p SS. This template
1244 /// parameter list may be have template parameters (if we're declaring a
1245 /// template) or may have no template parameters (if we're declaring a
1246 /// template specialization), or may be NULL (if we were's declaring isn't
1247 /// itself a template).
1248 TemplateParameterList *
1249 Sema::MatchTemplateParametersToScopeSpecifier(SourceLocation DeclStartLoc,
1250 const CXXScopeSpec &SS,
1251 TemplateParameterList **ParamLists,
1252 unsigned NumParamLists,
1254 bool &IsExplicitSpecialization,
1256 IsExplicitSpecialization = false;
1258 // Find the template-ids that occur within the nested-name-specifier. These
1259 // template-ids will match up with the template parameter lists.
1260 llvm::SmallVector<const TemplateSpecializationType *, 4>
1261 TemplateIdsInSpecifier;
1262 llvm::SmallVector<ClassTemplateSpecializationDecl *, 4>
1263 ExplicitSpecializationsInSpecifier;
1264 for (NestedNameSpecifier *NNS = (NestedNameSpecifier *)SS.getScopeRep();
1265 NNS; NNS = NNS->getPrefix()) {
1266 const Type *T = NNS->getAsType();
1269 // C++0x [temp.expl.spec]p17:
1270 // A member or a member template may be nested within many
1271 // enclosing class templates. In an explicit specialization for
1272 // such a member, the member declaration shall be preceded by a
1273 // template<> for each enclosing class template that is
1274 // explicitly specialized.
1276 // Following the existing practice of GNU and EDG, we allow a typedef of a
1277 // template specialization type.
1278 if (const TypedefType *TT = dyn_cast<TypedefType>(T))
1279 T = TT->LookThroughTypedefs().getTypePtr();
1281 if (const TemplateSpecializationType *SpecType
1282 = dyn_cast<TemplateSpecializationType>(T)) {
1283 TemplateDecl *Template = SpecType->getTemplateName().getAsTemplateDecl();
1285 continue; // FIXME: should this be an error? probably...
1287 if (const RecordType *Record = SpecType->getAs<RecordType>()) {
1288 ClassTemplateSpecializationDecl *SpecDecl
1289 = cast<ClassTemplateSpecializationDecl>(Record->getDecl());
1290 // If the nested name specifier refers to an explicit specialization,
1291 // we don't need a template<> header.
1292 if (SpecDecl->getSpecializationKind() == TSK_ExplicitSpecialization) {
1293 ExplicitSpecializationsInSpecifier.push_back(SpecDecl);
1298 TemplateIdsInSpecifier.push_back(SpecType);
1302 // Reverse the list of template-ids in the scope specifier, so that we can
1303 // more easily match up the template-ids and the template parameter lists.
1304 std::reverse(TemplateIdsInSpecifier.begin(), TemplateIdsInSpecifier.end());
1306 SourceLocation FirstTemplateLoc = DeclStartLoc;
1308 FirstTemplateLoc = ParamLists[0]->getTemplateLoc();
1310 // Match the template-ids found in the specifier to the template parameter
1313 for (unsigned NumTemplateIds = TemplateIdsInSpecifier.size();
1314 Idx != NumTemplateIds; ++Idx) {
1315 QualType TemplateId = QualType(TemplateIdsInSpecifier[Idx], 0);
1316 bool DependentTemplateId = TemplateId->isDependentType();
1317 if (Idx >= NumParamLists) {
1318 // We have a template-id without a corresponding template parameter
1321 // ...which is fine if this is a friend declaration.
1323 IsExplicitSpecialization = true;
1327 if (DependentTemplateId) {
1328 // FIXME: the location information here isn't great.
1329 Diag(SS.getRange().getBegin(),
1330 diag::err_template_spec_needs_template_parameters)
1335 Diag(SS.getRange().getBegin(), diag::err_template_spec_needs_header)
1337 << FixItHint::CreateInsertion(FirstTemplateLoc, "template<> ");
1338 IsExplicitSpecialization = true;
1343 // Check the template parameter list against its corresponding template-id.
1344 if (DependentTemplateId) {
1345 TemplateParameterList *ExpectedTemplateParams = 0;
1347 // Are there cases in (e.g.) friends where this won't match?
1348 if (const InjectedClassNameType *Injected
1349 = TemplateId->getAs<InjectedClassNameType>()) {
1350 CXXRecordDecl *Record = Injected->getDecl();
1351 if (ClassTemplatePartialSpecializationDecl *Partial =
1352 dyn_cast<ClassTemplatePartialSpecializationDecl>(Record))
1353 ExpectedTemplateParams = Partial->getTemplateParameters();
1355 ExpectedTemplateParams = Record->getDescribedClassTemplate()
1356 ->getTemplateParameters();
1359 if (ExpectedTemplateParams)
1360 TemplateParameterListsAreEqual(ParamLists[Idx],
1361 ExpectedTemplateParams,
1362 true, TPL_TemplateMatch);
1364 CheckTemplateParameterList(ParamLists[Idx], 0, TPC_ClassTemplateMember);
1365 } else if (ParamLists[Idx]->size() > 0)
1366 Diag(ParamLists[Idx]->getTemplateLoc(),
1367 diag::err_template_param_list_matches_nontemplate)
1369 << ParamLists[Idx]->getSourceRange();
1371 IsExplicitSpecialization = true;
1374 // If there were at least as many template-ids as there were template
1375 // parameter lists, then there are no template parameter lists remaining for
1376 // the declaration itself.
1377 if (Idx >= NumParamLists)
1380 // If there were too many template parameter lists, complain about that now.
1381 if (Idx != NumParamLists - 1) {
1382 while (Idx < NumParamLists - 1) {
1383 bool isExplicitSpecHeader = ParamLists[Idx]->size() == 0;
1384 Diag(ParamLists[Idx]->getTemplateLoc(),
1385 isExplicitSpecHeader? diag::warn_template_spec_extra_headers
1386 : diag::err_template_spec_extra_headers)
1387 << SourceRange(ParamLists[Idx]->getTemplateLoc(),
1388 ParamLists[Idx]->getRAngleLoc());
1390 if (isExplicitSpecHeader && !ExplicitSpecializationsInSpecifier.empty()) {
1391 Diag(ExplicitSpecializationsInSpecifier.back()->getLocation(),
1392 diag::note_explicit_template_spec_does_not_need_header)
1393 << ExplicitSpecializationsInSpecifier.back();
1394 ExplicitSpecializationsInSpecifier.pop_back();
1397 // We have a template parameter list with no corresponding scope, which
1398 // means that the resulting template declaration can't be instantiated
1399 // properly (we'll end up with dependent nodes when we shouldn't).
1400 if (!isExplicitSpecHeader)
1407 // Return the last template parameter list, which corresponds to the
1408 // entity being declared.
1409 return ParamLists[NumParamLists - 1];
1412 QualType Sema::CheckTemplateIdType(TemplateName Name,
1413 SourceLocation TemplateLoc,
1414 const TemplateArgumentListInfo &TemplateArgs) {
1415 TemplateDecl *Template = Name.getAsTemplateDecl();
1417 // The template name does not resolve to a template, so we just
1418 // build a dependent template-id type.
1419 return Context.getTemplateSpecializationType(Name, TemplateArgs);
1422 // Check that the template argument list is well-formed for this
1424 TemplateArgumentListBuilder Converted(Template->getTemplateParameters(),
1425 TemplateArgs.size());
1426 if (CheckTemplateArgumentList(Template, TemplateLoc, TemplateArgs,
1430 assert((Converted.structuredSize() ==
1431 Template->getTemplateParameters()->size()) &&
1432 "Converted template argument list is too short!");
1436 if (Name.isDependent() ||
1437 TemplateSpecializationType::anyDependentTemplateArguments(
1439 // This class template specialization is a dependent
1440 // type. Therefore, its canonical type is another class template
1441 // specialization type that contains all of the converted
1442 // arguments in canonical form. This ensures that, e.g., A<T> and
1443 // A<T, T> have identical types when A is declared as:
1445 // template<typename T, typename U = T> struct A;
1446 TemplateName CanonName = Context.getCanonicalTemplateName(Name);
1447 CanonType = Context.getTemplateSpecializationType(CanonName,
1448 Converted.getFlatArguments(),
1449 Converted.flatSize());
1451 // FIXME: CanonType is not actually the canonical type, and unfortunately
1452 // it is a TemplateSpecializationType that we will never use again.
1453 // In the future, we need to teach getTemplateSpecializationType to only
1454 // build the canonical type and return that to us.
1455 CanonType = Context.getCanonicalType(CanonType);
1457 // This might work out to be a current instantiation, in which
1458 // case the canonical type needs to be the InjectedClassNameType.
1460 // TODO: in theory this could be a simple hashtable lookup; most
1461 // changes to CurContext don't change the set of current
1463 if (isa<ClassTemplateDecl>(Template)) {
1464 for (DeclContext *Ctx = CurContext; Ctx; Ctx = Ctx->getLookupParent()) {
1465 // If we get out to a namespace, we're done.
1466 if (Ctx->isFileContext()) break;
1468 // If this isn't a record, keep looking.
1469 CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Ctx);
1470 if (!Record) continue;
1472 // Look for one of the two cases with InjectedClassNameTypes
1473 // and check whether it's the same template.
1474 if (!isa<ClassTemplatePartialSpecializationDecl>(Record) &&
1475 !Record->getDescribedClassTemplate())
1478 // Fetch the injected class name type and check whether its
1479 // injected type is equal to the type we just built.
1480 QualType ICNT = Context.getTypeDeclType(Record);
1481 QualType Injected = cast<InjectedClassNameType>(ICNT)
1482 ->getInjectedSpecializationType();
1484 if (CanonType != Injected->getCanonicalTypeInternal())
1487 // If so, the canonical type of this TST is the injected
1488 // class name type of the record we just found.
1489 assert(ICNT.isCanonical());
1494 } else if (ClassTemplateDecl *ClassTemplate
1495 = dyn_cast<ClassTemplateDecl>(Template)) {
1496 // Find the class template specialization declaration that
1497 // corresponds to these arguments.
1498 void *InsertPos = 0;
1499 ClassTemplateSpecializationDecl *Decl
1500 = ClassTemplate->findSpecialization(Converted.getFlatArguments(),
1501 Converted.flatSize(), InsertPos);
1503 // This is the first time we have referenced this class template
1504 // specialization. Create the canonical declaration and add it to
1505 // the set of specializations.
1506 Decl = ClassTemplateSpecializationDecl::Create(Context,
1507 ClassTemplate->getTemplatedDecl()->getTagKind(),
1508 ClassTemplate->getDeclContext(),
1509 ClassTemplate->getLocation(),
1512 ClassTemplate->AddSpecialization(Decl, InsertPos);
1513 Decl->setLexicalDeclContext(CurContext);
1516 CanonType = Context.getTypeDeclType(Decl);
1517 assert(isa<RecordType>(CanonType) &&
1518 "type of non-dependent specialization is not a RecordType");
1521 // Build the fully-sugared type for this class template
1522 // specialization, which refers back to the class template
1523 // specialization we created or found.
1524 return Context.getTemplateSpecializationType(Name, TemplateArgs, CanonType);
1528 Sema::ActOnTemplateIdType(TemplateTy TemplateD, SourceLocation TemplateLoc,
1529 SourceLocation LAngleLoc,
1530 ASTTemplateArgsPtr TemplateArgsIn,
1531 SourceLocation RAngleLoc) {
1532 TemplateName Template = TemplateD.getAsVal<TemplateName>();
1534 // Translate the parser's template argument list in our AST format.
1535 TemplateArgumentListInfo TemplateArgs(LAngleLoc, RAngleLoc);
1536 translateTemplateArguments(TemplateArgsIn, TemplateArgs);
1538 QualType Result = CheckTemplateIdType(Template, TemplateLoc, TemplateArgs);
1539 TemplateArgsIn.release();
1541 if (Result.isNull())
1544 TypeSourceInfo *DI = Context.CreateTypeSourceInfo(Result);
1545 TemplateSpecializationTypeLoc TL
1546 = cast<TemplateSpecializationTypeLoc>(DI->getTypeLoc());
1547 TL.setTemplateNameLoc(TemplateLoc);
1548 TL.setLAngleLoc(LAngleLoc);
1549 TL.setRAngleLoc(RAngleLoc);
1550 for (unsigned i = 0, e = TL.getNumArgs(); i != e; ++i)
1551 TL.setArgLocInfo(i, TemplateArgs[i].getLocInfo());
1553 return CreateParsedType(Result, DI);
1556 TypeResult Sema::ActOnTagTemplateIdType(TypeResult TypeResult,
1558 TypeSpecifierType TagSpec,
1559 SourceLocation TagLoc) {
1560 if (TypeResult.isInvalid())
1561 return ::TypeResult();
1563 // FIXME: preserve source info, ideally without copying the DI.
1565 QualType Type = GetTypeFromParser(TypeResult.get(), &DI);
1567 // Verify the tag specifier.
1568 TagTypeKind TagKind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec);
1570 if (const RecordType *RT = Type->getAs<RecordType>()) {
1571 RecordDecl *D = RT->getDecl();
1573 IdentifierInfo *Id = D->getIdentifier();
1574 assert(Id && "templated class must have an identifier");
1576 if (!isAcceptableTagRedeclaration(D, TagKind, TagLoc, *Id)) {
1577 Diag(TagLoc, diag::err_use_with_wrong_tag)
1579 << FixItHint::CreateReplacement(SourceRange(TagLoc), D->getKindName());
1580 Diag(D->getLocation(), diag::note_previous_use);
1584 ElaboratedTypeKeyword Keyword
1585 = TypeWithKeyword::getKeywordForTagTypeKind(TagKind);
1586 QualType ElabType = Context.getElaboratedType(Keyword, /*NNS=*/0, Type);
1588 return ParsedType::make(ElabType);
1591 ExprResult Sema::BuildTemplateIdExpr(const CXXScopeSpec &SS,
1594 const TemplateArgumentListInfo &TemplateArgs) {
1595 // FIXME: Can we do any checking at this point? I guess we could check the
1596 // template arguments that we have against the template name, if the template
1597 // name refers to a single template. That's not a terribly common case,
1600 // These should be filtered out by our callers.
1601 assert(!R.empty() && "empty lookup results when building templateid");
1602 assert(!R.isAmbiguous() && "ambiguous lookup when building templateid");
1604 NestedNameSpecifier *Qualifier = 0;
1605 SourceRange QualifierRange;
1607 Qualifier = static_cast<NestedNameSpecifier*>(SS.getScopeRep());
1608 QualifierRange = SS.getRange();
1611 // We don't want lookup warnings at this point.
1612 R.suppressDiagnostics();
1615 = UnresolvedLookupExpr::ComputeDependence(R.begin(), R.end(),
1617 UnresolvedLookupExpr *ULE
1618 = UnresolvedLookupExpr::Create(Context, Dependent, R.getNamingClass(),
1619 Qualifier, QualifierRange,
1620 R.getLookupNameInfo(),
1621 RequiresADL, TemplateArgs,
1622 R.begin(), R.end());
1627 // We actually only call this from template instantiation.
1629 Sema::BuildQualifiedTemplateIdExpr(CXXScopeSpec &SS,
1630 const DeclarationNameInfo &NameInfo,
1631 const TemplateArgumentListInfo &TemplateArgs) {
1633 if (!(DC = computeDeclContext(SS, false)) ||
1634 DC->isDependentContext() ||
1635 RequireCompleteDeclContext(SS, DC))
1636 return BuildDependentDeclRefExpr(SS, NameInfo, &TemplateArgs);
1638 bool MemberOfUnknownSpecialization;
1639 LookupResult R(*this, NameInfo, LookupOrdinaryName);
1640 LookupTemplateName(R, (Scope*) 0, SS, QualType(), /*Entering*/ false,
1641 MemberOfUnknownSpecialization);
1643 if (R.isAmbiguous())
1647 Diag(NameInfo.getLoc(), diag::err_template_kw_refers_to_non_template)
1648 << NameInfo.getName() << SS.getRange();
1652 if (ClassTemplateDecl *Temp = R.getAsSingle<ClassTemplateDecl>()) {
1653 Diag(NameInfo.getLoc(), diag::err_template_kw_refers_to_class_template)
1654 << (NestedNameSpecifier*) SS.getScopeRep()
1655 << NameInfo.getName() << SS.getRange();
1656 Diag(Temp->getLocation(), diag::note_referenced_class_template);
1660 return BuildTemplateIdExpr(SS, R, /* ADL */ false, TemplateArgs);
1663 /// \brief Form a dependent template name.
1665 /// This action forms a dependent template name given the template
1666 /// name and its (presumably dependent) scope specifier. For
1667 /// example, given "MetaFun::template apply", the scope specifier \p
1668 /// SS will be "MetaFun::", \p TemplateKWLoc contains the location
1669 /// of the "template" keyword, and "apply" is the \p Name.
1670 TemplateNameKind Sema::ActOnDependentTemplateName(Scope *S,
1671 SourceLocation TemplateKWLoc,
1673 UnqualifiedId &Name,
1674 ParsedType ObjectType,
1675 bool EnteringContext,
1676 TemplateTy &Result) {
1677 if (TemplateKWLoc.isValid() && S && !S->getTemplateParamParent() &&
1678 !getLangOptions().CPlusPlus0x)
1679 Diag(TemplateKWLoc, diag::ext_template_outside_of_template)
1680 << FixItHint::CreateRemoval(TemplateKWLoc);
1682 DeclContext *LookupCtx = 0;
1684 LookupCtx = computeDeclContext(SS, EnteringContext);
1685 if (!LookupCtx && ObjectType)
1686 LookupCtx = computeDeclContext(ObjectType.get());
1688 // C++0x [temp.names]p5:
1689 // If a name prefixed by the keyword template is not the name of
1690 // a template, the program is ill-formed. [Note: the keyword
1691 // template may not be applied to non-template members of class
1692 // templates. -end note ] [ Note: as is the case with the
1693 // typename prefix, the template prefix is allowed in cases
1694 // where it is not strictly necessary; i.e., when the
1695 // nested-name-specifier or the expression on the left of the ->
1696 // or . is not dependent on a template-parameter, or the use
1697 // does not appear in the scope of a template. -end note]
1699 // Note: C++03 was more strict here, because it banned the use of
1700 // the "template" keyword prior to a template-name that was not a
1701 // dependent name. C++ DR468 relaxed this requirement (the
1702 // "template" keyword is now permitted). We follow the C++0x
1703 // rules, even in C++03 mode with a warning, retroactively applying the DR.
1704 bool MemberOfUnknownSpecialization;
1705 TemplateNameKind TNK = isTemplateName(0, SS, TemplateKWLoc.isValid(), Name,
1706 ObjectType, EnteringContext, Result,
1707 MemberOfUnknownSpecialization);
1708 if (TNK == TNK_Non_template && LookupCtx->isDependentContext() &&
1709 isa<CXXRecordDecl>(LookupCtx) &&
1710 cast<CXXRecordDecl>(LookupCtx)->hasAnyDependentBases()) {
1711 // This is a dependent template. Handle it below.
1712 } else if (TNK == TNK_Non_template) {
1713 Diag(Name.getSourceRange().getBegin(),
1714 diag::err_template_kw_refers_to_non_template)
1715 << GetNameFromUnqualifiedId(Name).getName()
1716 << Name.getSourceRange()
1718 return TNK_Non_template;
1720 // We found something; return it.
1725 NestedNameSpecifier *Qualifier
1726 = static_cast<NestedNameSpecifier *>(SS.getScopeRep());
1728 switch (Name.getKind()) {
1729 case UnqualifiedId::IK_Identifier:
1730 Result = TemplateTy::make(Context.getDependentTemplateName(Qualifier,
1732 return TNK_Dependent_template_name;
1734 case UnqualifiedId::IK_OperatorFunctionId:
1735 Result = TemplateTy::make(Context.getDependentTemplateName(Qualifier,
1736 Name.OperatorFunctionId.Operator));
1737 return TNK_Dependent_template_name;
1739 case UnqualifiedId::IK_LiteralOperatorId:
1740 assert(false && "We don't support these; Parse shouldn't have allowed propagation");
1746 Diag(Name.getSourceRange().getBegin(),
1747 diag::err_template_kw_refers_to_non_template)
1748 << GetNameFromUnqualifiedId(Name).getName()
1749 << Name.getSourceRange()
1751 return TNK_Non_template;
1754 bool Sema::CheckTemplateTypeArgument(TemplateTypeParmDecl *Param,
1755 const TemplateArgumentLoc &AL,
1756 TemplateArgumentListBuilder &Converted) {
1757 const TemplateArgument &Arg = AL.getArgument();
1759 // Check template type parameter.
1760 switch(Arg.getKind()) {
1761 case TemplateArgument::Type:
1762 // C++ [temp.arg.type]p1:
1763 // A template-argument for a template-parameter which is a
1764 // type shall be a type-id.
1766 case TemplateArgument::Template: {
1767 // We have a template type parameter but the template argument
1768 // is a template without any arguments.
1769 SourceRange SR = AL.getSourceRange();
1770 TemplateName Name = Arg.getAsTemplate();
1771 Diag(SR.getBegin(), diag::err_template_missing_args)
1773 if (TemplateDecl *Decl = Name.getAsTemplateDecl())
1774 Diag(Decl->getLocation(), diag::note_template_decl_here);
1779 // We have a template type parameter but the template argument
1781 SourceRange SR = AL.getSourceRange();
1782 Diag(SR.getBegin(), diag::err_template_arg_must_be_type) << SR;
1783 Diag(Param->getLocation(), diag::note_template_param_here);
1789 if (CheckTemplateArgument(Param, AL.getTypeSourceInfo()))
1792 // Add the converted template type argument.
1794 TemplateArgument(Context.getCanonicalType(Arg.getAsType())));
1798 /// \brief Substitute template arguments into the default template argument for
1799 /// the given template type parameter.
1801 /// \param SemaRef the semantic analysis object for which we are performing
1802 /// the substitution.
1804 /// \param Template the template that we are synthesizing template arguments
1807 /// \param TemplateLoc the location of the template name that started the
1808 /// template-id we are checking.
1810 /// \param RAngleLoc the location of the right angle bracket ('>') that
1811 /// terminates the template-id.
1813 /// \param Param the template template parameter whose default we are
1814 /// substituting into.
1816 /// \param Converted the list of template arguments provided for template
1817 /// parameters that precede \p Param in the template parameter list.
1819 /// \returns the substituted template argument, or NULL if an error occurred.
1820 static TypeSourceInfo *
1821 SubstDefaultTemplateArgument(Sema &SemaRef,
1822 TemplateDecl *Template,
1823 SourceLocation TemplateLoc,
1824 SourceLocation RAngleLoc,
1825 TemplateTypeParmDecl *Param,
1826 TemplateArgumentListBuilder &Converted) {
1827 TypeSourceInfo *ArgType = Param->getDefaultArgumentInfo();
1829 // If the argument type is dependent, instantiate it now based
1830 // on the previously-computed template arguments.
1831 if (ArgType->getType()->isDependentType()) {
1832 TemplateArgumentList TemplateArgs(SemaRef.Context, Converted,
1833 /*TakeArgs=*/false);
1835 MultiLevelTemplateArgumentList AllTemplateArgs
1836 = SemaRef.getTemplateInstantiationArgs(Template, &TemplateArgs);
1838 Sema::InstantiatingTemplate Inst(SemaRef, TemplateLoc,
1839 Template, Converted.getFlatArguments(),
1840 Converted.flatSize(),
1841 SourceRange(TemplateLoc, RAngleLoc));
1843 ArgType = SemaRef.SubstType(ArgType, AllTemplateArgs,
1844 Param->getDefaultArgumentLoc(),
1845 Param->getDeclName());
1851 /// \brief Substitute template arguments into the default template argument for
1852 /// the given non-type template parameter.
1854 /// \param SemaRef the semantic analysis object for which we are performing
1855 /// the substitution.
1857 /// \param Template the template that we are synthesizing template arguments
1860 /// \param TemplateLoc the location of the template name that started the
1861 /// template-id we are checking.
1863 /// \param RAngleLoc the location of the right angle bracket ('>') that
1864 /// terminates the template-id.
1866 /// \param Param the non-type template parameter whose default we are
1867 /// substituting into.
1869 /// \param Converted the list of template arguments provided for template
1870 /// parameters that precede \p Param in the template parameter list.
1872 /// \returns the substituted template argument, or NULL if an error occurred.
1874 SubstDefaultTemplateArgument(Sema &SemaRef,
1875 TemplateDecl *Template,
1876 SourceLocation TemplateLoc,
1877 SourceLocation RAngleLoc,
1878 NonTypeTemplateParmDecl *Param,
1879 TemplateArgumentListBuilder &Converted) {
1880 TemplateArgumentList TemplateArgs(SemaRef.Context, Converted,
1881 /*TakeArgs=*/false);
1883 MultiLevelTemplateArgumentList AllTemplateArgs
1884 = SemaRef.getTemplateInstantiationArgs(Template, &TemplateArgs);
1886 Sema::InstantiatingTemplate Inst(SemaRef, TemplateLoc,
1887 Template, Converted.getFlatArguments(),
1888 Converted.flatSize(),
1889 SourceRange(TemplateLoc, RAngleLoc));
1891 return SemaRef.SubstExpr(Param->getDefaultArgument(), AllTemplateArgs);
1894 /// \brief Substitute template arguments into the default template argument for
1895 /// the given template template parameter.
1897 /// \param SemaRef the semantic analysis object for which we are performing
1898 /// the substitution.
1900 /// \param Template the template that we are synthesizing template arguments
1903 /// \param TemplateLoc the location of the template name that started the
1904 /// template-id we are checking.
1906 /// \param RAngleLoc the location of the right angle bracket ('>') that
1907 /// terminates the template-id.
1909 /// \param Param the template template parameter whose default we are
1910 /// substituting into.
1912 /// \param Converted the list of template arguments provided for template
1913 /// parameters that precede \p Param in the template parameter list.
1915 /// \returns the substituted template argument, or NULL if an error occurred.
1917 SubstDefaultTemplateArgument(Sema &SemaRef,
1918 TemplateDecl *Template,
1919 SourceLocation TemplateLoc,
1920 SourceLocation RAngleLoc,
1921 TemplateTemplateParmDecl *Param,
1922 TemplateArgumentListBuilder &Converted) {
1923 TemplateArgumentList TemplateArgs(SemaRef.Context, Converted,
1924 /*TakeArgs=*/false);
1926 MultiLevelTemplateArgumentList AllTemplateArgs
1927 = SemaRef.getTemplateInstantiationArgs(Template, &TemplateArgs);
1929 Sema::InstantiatingTemplate Inst(SemaRef, TemplateLoc,
1930 Template, Converted.getFlatArguments(),
1931 Converted.flatSize(),
1932 SourceRange(TemplateLoc, RAngleLoc));
1934 return SemaRef.SubstTemplateName(
1935 Param->getDefaultArgument().getArgument().getAsTemplate(),
1936 Param->getDefaultArgument().getTemplateNameLoc(),
1940 /// \brief If the given template parameter has a default template
1941 /// argument, substitute into that default template argument and
1942 /// return the corresponding template argument.
1944 Sema::SubstDefaultTemplateArgumentIfAvailable(TemplateDecl *Template,
1945 SourceLocation TemplateLoc,
1946 SourceLocation RAngleLoc,
1948 TemplateArgumentListBuilder &Converted) {
1949 if (TemplateTypeParmDecl *TypeParm = dyn_cast<TemplateTypeParmDecl>(Param)) {
1950 if (!TypeParm->hasDefaultArgument())
1951 return TemplateArgumentLoc();
1953 TypeSourceInfo *DI = SubstDefaultTemplateArgument(*this, Template,
1959 return TemplateArgumentLoc(TemplateArgument(DI->getType()), DI);
1961 return TemplateArgumentLoc();
1964 if (NonTypeTemplateParmDecl *NonTypeParm
1965 = dyn_cast<NonTypeTemplateParmDecl>(Param)) {
1966 if (!NonTypeParm->hasDefaultArgument())
1967 return TemplateArgumentLoc();
1969 ExprResult Arg = SubstDefaultTemplateArgument(*this, Template,
1974 if (Arg.isInvalid())
1975 return TemplateArgumentLoc();
1977 Expr *ArgE = Arg.takeAs<Expr>();
1978 return TemplateArgumentLoc(TemplateArgument(ArgE), ArgE);
1981 TemplateTemplateParmDecl *TempTempParm
1982 = cast<TemplateTemplateParmDecl>(Param);
1983 if (!TempTempParm->hasDefaultArgument())
1984 return TemplateArgumentLoc();
1986 TemplateName TName = SubstDefaultTemplateArgument(*this, Template,
1992 return TemplateArgumentLoc();
1994 return TemplateArgumentLoc(TemplateArgument(TName),
1995 TempTempParm->getDefaultArgument().getTemplateQualifierRange(),
1996 TempTempParm->getDefaultArgument().getTemplateNameLoc());
1999 /// \brief Check that the given template argument corresponds to the given
2000 /// template parameter.
2001 bool Sema::CheckTemplateArgument(NamedDecl *Param,
2002 const TemplateArgumentLoc &Arg,
2003 TemplateDecl *Template,
2004 SourceLocation TemplateLoc,
2005 SourceLocation RAngleLoc,
2006 TemplateArgumentListBuilder &Converted,
2007 CheckTemplateArgumentKind CTAK) {
2008 // Check template type parameters.
2009 if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(Param))
2010 return CheckTemplateTypeArgument(TTP, Arg, Converted);
2012 // Check non-type template parameters.
2013 if (NonTypeTemplateParmDecl *NTTP =dyn_cast<NonTypeTemplateParmDecl>(Param)) {
2014 // Do substitution on the type of the non-type template parameter
2015 // with the template arguments we've seen thus far.
2016 QualType NTTPType = NTTP->getType();
2017 if (NTTPType->isDependentType()) {
2018 // Do substitution on the type of the non-type template parameter.
2019 InstantiatingTemplate Inst(*this, TemplateLoc, Template,
2020 NTTP, Converted.getFlatArguments(),
2021 Converted.flatSize(),
2022 SourceRange(TemplateLoc, RAngleLoc));
2024 TemplateArgumentList TemplateArgs(Context, Converted,
2025 /*TakeArgs=*/false);
2026 NTTPType = SubstType(NTTPType,
2027 MultiLevelTemplateArgumentList(TemplateArgs),
2028 NTTP->getLocation(),
2029 NTTP->getDeclName());
2030 // If that worked, check the non-type template parameter type
2032 if (!NTTPType.isNull())
2033 NTTPType = CheckNonTypeTemplateParameterType(NTTPType,
2034 NTTP->getLocation());
2035 if (NTTPType.isNull())
2039 switch (Arg.getArgument().getKind()) {
2040 case TemplateArgument::Null:
2041 assert(false && "Should never see a NULL template argument here");
2044 case TemplateArgument::Expression: {
2045 Expr *E = Arg.getArgument().getAsExpr();
2046 TemplateArgument Result;
2047 if (CheckTemplateArgument(NTTP, NTTPType, E, Result, CTAK))
2050 Converted.Append(Result);
2054 case TemplateArgument::Declaration:
2055 case TemplateArgument::Integral:
2056 // We've already checked this template argument, so just copy
2057 // it to the list of converted arguments.
2058 Converted.Append(Arg.getArgument());
2061 case TemplateArgument::Template:
2062 // We were given a template template argument. It may not be ill-formed;
2064 if (DependentTemplateName *DTN
2065 = Arg.getArgument().getAsTemplate().getAsDependentTemplateName()) {
2066 // We have a template argument such as \c T::template X, which we
2067 // parsed as a template template argument. However, since we now
2068 // know that we need a non-type template argument, convert this
2069 // template name into an expression.
2071 DeclarationNameInfo NameInfo(DTN->getIdentifier(),
2072 Arg.getTemplateNameLoc());
2074 Expr *E = DependentScopeDeclRefExpr::Create(Context,
2075 DTN->getQualifier(),
2076 Arg.getTemplateQualifierRange(),
2079 TemplateArgument Result;
2080 if (CheckTemplateArgument(NTTP, NTTPType, E, Result))
2083 Converted.Append(Result);
2087 // We have a template argument that actually does refer to a class
2088 // template, template alias, or template template parameter, and
2089 // therefore cannot be a non-type template argument.
2090 Diag(Arg.getLocation(), diag::err_template_arg_must_be_expr)
2091 << Arg.getSourceRange();
2093 Diag(Param->getLocation(), diag::note_template_param_here);
2096 case TemplateArgument::Type: {
2097 // We have a non-type template parameter but the template
2098 // argument is a type.
2100 // C++ [temp.arg]p2:
2101 // In a template-argument, an ambiguity between a type-id and
2102 // an expression is resolved to a type-id, regardless of the
2103 // form of the corresponding template-parameter.
2105 // We warn specifically about this case, since it can be rather
2106 // confusing for users.
2107 QualType T = Arg.getArgument().getAsType();
2108 SourceRange SR = Arg.getSourceRange();
2109 if (T->isFunctionType())
2110 Diag(SR.getBegin(), diag::err_template_arg_nontype_ambig) << SR << T;
2112 Diag(SR.getBegin(), diag::err_template_arg_must_be_expr) << SR;
2113 Diag(Param->getLocation(), diag::note_template_param_here);
2117 case TemplateArgument::Pack:
2118 llvm_unreachable("Caller must expand template argument packs");
2126 // Check template template parameters.
2127 TemplateTemplateParmDecl *TempParm = cast<TemplateTemplateParmDecl>(Param);
2129 // Substitute into the template parameter list of the template
2130 // template parameter, since previously-supplied template arguments
2131 // may appear within the template template parameter.
2133 // Set up a template instantiation context.
2134 LocalInstantiationScope Scope(*this);
2135 InstantiatingTemplate Inst(*this, TemplateLoc, Template,
2136 TempParm, Converted.getFlatArguments(),
2137 Converted.flatSize(),
2138 SourceRange(TemplateLoc, RAngleLoc));
2140 TemplateArgumentList TemplateArgs(Context, Converted,
2141 /*TakeArgs=*/false);
2142 TempParm = cast_or_null<TemplateTemplateParmDecl>(
2143 SubstDecl(TempParm, CurContext,
2144 MultiLevelTemplateArgumentList(TemplateArgs)));
2148 // FIXME: TempParam is leaked.
2151 switch (Arg.getArgument().getKind()) {
2152 case TemplateArgument::Null:
2153 assert(false && "Should never see a NULL template argument here");
2156 case TemplateArgument::Template:
2157 if (CheckTemplateArgument(TempParm, Arg))
2160 Converted.Append(Arg.getArgument());
2163 case TemplateArgument::Expression:
2164 case TemplateArgument::Type:
2165 // We have a template template parameter but the template
2166 // argument does not refer to a template.
2167 Diag(Arg.getLocation(), diag::err_template_arg_must_be_template);
2170 case TemplateArgument::Declaration:
2172 "Declaration argument with template template parameter");
2174 case TemplateArgument::Integral:
2176 "Integral argument with template template parameter");
2179 case TemplateArgument::Pack:
2180 llvm_unreachable("Caller must expand template argument packs");
2187 /// \brief Check that the given template argument list is well-formed
2188 /// for specializing the given template.
2189 bool Sema::CheckTemplateArgumentList(TemplateDecl *Template,
2190 SourceLocation TemplateLoc,
2191 const TemplateArgumentListInfo &TemplateArgs,
2192 bool PartialTemplateArgs,
2193 TemplateArgumentListBuilder &Converted) {
2194 TemplateParameterList *Params = Template->getTemplateParameters();
2195 unsigned NumParams = Params->size();
2196 unsigned NumArgs = TemplateArgs.size();
2197 bool Invalid = false;
2199 SourceLocation RAngleLoc = TemplateArgs.getRAngleLoc();
2201 bool HasParameterPack =
2202 NumParams > 0 && Params->getParam(NumParams - 1)->isTemplateParameterPack();
2204 if ((NumArgs > NumParams && !HasParameterPack) ||
2205 (NumArgs < Params->getMinRequiredArguments() &&
2206 !PartialTemplateArgs)) {
2207 // FIXME: point at either the first arg beyond what we can handle,
2208 // or the '>', depending on whether we have too many or too few
2211 if (NumArgs > NumParams)
2212 Range = SourceRange(TemplateArgs[NumParams].getLocation(), RAngleLoc);
2213 Diag(TemplateLoc, diag::err_template_arg_list_different_arity)
2214 << (NumArgs > NumParams)
2215 << (isa<ClassTemplateDecl>(Template)? 0 :
2216 isa<FunctionTemplateDecl>(Template)? 1 :
2217 isa<TemplateTemplateParmDecl>(Template)? 2 : 3)
2218 << Template << Range;
2219 Diag(Template->getLocation(), diag::note_template_decl_here)
2220 << Params->getSourceRange();
2224 // C++ [temp.arg]p1:
2225 // [...] The type and form of each template-argument specified in
2226 // a template-id shall match the type and form specified for the
2227 // corresponding parameter declared by the template in its
2228 // template-parameter-list.
2229 unsigned ArgIdx = 0;
2230 for (TemplateParameterList::iterator Param = Params->begin(),
2231 ParamEnd = Params->end();
2232 Param != ParamEnd; ++Param, ++ArgIdx) {
2233 if (ArgIdx > NumArgs && PartialTemplateArgs)
2236 // If we have a template parameter pack, check every remaining template
2237 // argument against that template parameter pack.
2238 if ((*Param)->isTemplateParameterPack()) {
2239 Converted.BeginPack();
2240 for (; ArgIdx < NumArgs; ++ArgIdx) {
2241 if (CheckTemplateArgument(*Param, TemplateArgs[ArgIdx], Template,
2242 TemplateLoc, RAngleLoc, Converted)) {
2247 Converted.EndPack();
2251 if (ArgIdx < NumArgs) {
2252 // Check the template argument we were given.
2253 if (CheckTemplateArgument(*Param, TemplateArgs[ArgIdx], Template,
2254 TemplateLoc, RAngleLoc, Converted))
2260 // We have a default template argument that we will use.
2261 TemplateArgumentLoc Arg;
2263 // Retrieve the default template argument from the template
2264 // parameter. For each kind of template parameter, we substitute the
2265 // template arguments provided thus far and any "outer" template arguments
2266 // (when the template parameter was part of a nested template) into
2267 // the default argument.
2268 if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(*Param)) {
2269 if (!TTP->hasDefaultArgument()) {
2270 assert((Invalid || PartialTemplateArgs) && "Missing default argument");
2274 TypeSourceInfo *ArgType = SubstDefaultTemplateArgument(*this,
2283 Arg = TemplateArgumentLoc(TemplateArgument(ArgType->getType()),
2285 } else if (NonTypeTemplateParmDecl *NTTP
2286 = dyn_cast<NonTypeTemplateParmDecl>(*Param)) {
2287 if (!NTTP->hasDefaultArgument()) {
2288 assert((Invalid || PartialTemplateArgs) && "Missing default argument");
2292 ExprResult E = SubstDefaultTemplateArgument(*this, Template,
2300 Expr *Ex = E.takeAs<Expr>();
2301 Arg = TemplateArgumentLoc(TemplateArgument(Ex), Ex);
2303 TemplateTemplateParmDecl *TempParm
2304 = cast<TemplateTemplateParmDecl>(*Param);
2306 if (!TempParm->hasDefaultArgument()) {
2307 assert((Invalid || PartialTemplateArgs) && "Missing default argument");
2311 TemplateName Name = SubstDefaultTemplateArgument(*this, Template,
2319 Arg = TemplateArgumentLoc(TemplateArgument(Name),
2320 TempParm->getDefaultArgument().getTemplateQualifierRange(),
2321 TempParm->getDefaultArgument().getTemplateNameLoc());
2324 // Introduce an instantiation record that describes where we are using
2325 // the default template argument.
2326 InstantiatingTemplate Instantiating(*this, RAngleLoc, Template, *Param,
2327 Converted.getFlatArguments(),
2328 Converted.flatSize(),
2329 SourceRange(TemplateLoc, RAngleLoc));
2331 // Check the default template argument.
2332 if (CheckTemplateArgument(*Param, Arg, Template, TemplateLoc,
2333 RAngleLoc, Converted))
2340 /// \brief Check a template argument against its corresponding
2341 /// template type parameter.
2343 /// This routine implements the semantics of C++ [temp.arg.type]. It
2344 /// returns true if an error occurred, and false otherwise.
2345 bool Sema::CheckTemplateArgument(TemplateTypeParmDecl *Param,
2346 TypeSourceInfo *ArgInfo) {
2347 assert(ArgInfo && "invalid TypeSourceInfo");
2348 QualType Arg = ArgInfo->getType();
2350 // C++03 [temp.arg.type]p2:
2351 // A local type, a type with no linkage, an unnamed type or a type
2352 // compounded from any of these types shall not be used as a
2353 // template-argument for a template type-parameter.
2354 // C++0x allows these, and even in C++03 we allow them as an extension with
2356 SourceRange SR = ArgInfo->getTypeLoc().getSourceRange();
2357 if (!LangOpts.CPlusPlus0x) {
2358 const TagType *Tag = 0;
2359 if (const EnumType *EnumT = Arg->getAs<EnumType>())
2361 else if (const RecordType *RecordT = Arg->getAs<RecordType>())
2363 if (Tag && Tag->getDecl()->getDeclContext()->isFunctionOrMethod()) {
2364 SourceRange SR = ArgInfo->getTypeLoc().getSourceRange();
2365 Diag(SR.getBegin(), diag::ext_template_arg_local_type)
2366 << QualType(Tag, 0) << SR;
2367 } else if (Tag && !Tag->getDecl()->getDeclName() &&
2368 !Tag->getDecl()->getTypedefForAnonDecl()) {
2369 Diag(SR.getBegin(), diag::ext_template_arg_unnamed_type) << SR;
2370 Diag(Tag->getDecl()->getLocation(),
2371 diag::note_template_unnamed_type_here);
2375 if (Arg->isVariablyModifiedType()) {
2376 return Diag(SR.getBegin(), diag::err_variably_modified_template_arg) << Arg;
2377 } else if (Context.hasSameUnqualifiedType(Arg, Context.OverloadTy)) {
2378 return Diag(SR.getBegin(), diag::err_template_arg_overload_type) << SR;
2384 /// \brief Checks whether the given template argument is the address
2385 /// of an object or function according to C++ [temp.arg.nontype]p1.
2387 CheckTemplateArgumentAddressOfObjectOrFunction(Sema &S,
2388 NonTypeTemplateParmDecl *Param,
2391 TemplateArgument &Converted) {
2392 bool Invalid = false;
2394 QualType ArgType = Arg->getType();
2396 // See through any implicit casts we added to fix the type.
2397 while (ImplicitCastExpr *Cast = dyn_cast<ImplicitCastExpr>(Arg))
2398 Arg = Cast->getSubExpr();
2400 // C++ [temp.arg.nontype]p1:
2402 // A template-argument for a non-type, non-template
2403 // template-parameter shall be one of: [...]
2405 // -- the address of an object or function with external
2406 // linkage, including function templates and function
2407 // template-ids but excluding non-static class members,
2408 // expressed as & id-expression where the & is optional if
2409 // the name refers to a function or array, or if the
2410 // corresponding template-parameter is a reference; or
2411 DeclRefExpr *DRE = 0;
2413 // Ignore (and complain about) any excess parentheses.
2414 while (ParenExpr *Parens = dyn_cast<ParenExpr>(Arg)) {
2416 S.Diag(Arg->getSourceRange().getBegin(),
2417 diag::err_template_arg_extra_parens)
2418 << Arg->getSourceRange();
2422 Arg = Parens->getSubExpr();
2425 bool AddressTaken = false;
2426 SourceLocation AddrOpLoc;
2427 if (UnaryOperator *UnOp = dyn_cast<UnaryOperator>(Arg)) {
2428 if (UnOp->getOpcode() == UO_AddrOf) {
2429 DRE = dyn_cast<DeclRefExpr>(UnOp->getSubExpr());
2430 AddressTaken = true;
2431 AddrOpLoc = UnOp->getOperatorLoc();
2434 DRE = dyn_cast<DeclRefExpr>(Arg);
2437 S.Diag(Arg->getLocStart(), diag::err_template_arg_not_decl_ref)
2438 << Arg->getSourceRange();
2439 S.Diag(Param->getLocation(), diag::note_template_param_here);
2443 // Stop checking the precise nature of the argument if it is value dependent,
2444 // it should be checked when instantiated.
2445 if (Arg->isValueDependent()) {
2446 Converted = TemplateArgument(ArgIn->Retain());
2450 if (!isa<ValueDecl>(DRE->getDecl())) {
2451 S.Diag(Arg->getSourceRange().getBegin(),
2452 diag::err_template_arg_not_object_or_func_form)
2453 << Arg->getSourceRange();
2454 S.Diag(Param->getLocation(), diag::note_template_param_here);
2458 NamedDecl *Entity = 0;
2460 // Cannot refer to non-static data members
2461 if (FieldDecl *Field = dyn_cast<FieldDecl>(DRE->getDecl())) {
2462 S.Diag(Arg->getSourceRange().getBegin(), diag::err_template_arg_field)
2463 << Field << Arg->getSourceRange();
2464 S.Diag(Param->getLocation(), diag::note_template_param_here);
2468 // Cannot refer to non-static member functions
2469 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(DRE->getDecl()))
2470 if (!Method->isStatic()) {
2471 S.Diag(Arg->getSourceRange().getBegin(), diag::err_template_arg_method)
2472 << Method << Arg->getSourceRange();
2473 S.Diag(Param->getLocation(), diag::note_template_param_here);
2477 // Functions must have external linkage.
2478 if (FunctionDecl *Func = dyn_cast<FunctionDecl>(DRE->getDecl())) {
2479 if (!isExternalLinkage(Func->getLinkage())) {
2480 S.Diag(Arg->getSourceRange().getBegin(),
2481 diag::err_template_arg_function_not_extern)
2482 << Func << Arg->getSourceRange();
2483 S.Diag(Func->getLocation(), diag::note_template_arg_internal_object)
2488 // Okay: we've named a function with external linkage.
2491 // If the template parameter has pointer type, the function decays.
2492 if (ParamType->isPointerType() && !AddressTaken)
2493 ArgType = S.Context.getPointerType(Func->getType());
2494 else if (AddressTaken && ParamType->isReferenceType()) {
2495 // If we originally had an address-of operator, but the
2496 // parameter has reference type, complain and (if things look
2497 // like they will work) drop the address-of operator.
2498 if (!S.Context.hasSameUnqualifiedType(Func->getType(),
2499 ParamType.getNonReferenceType())) {
2500 S.Diag(AddrOpLoc, diag::err_template_arg_address_of_non_pointer)
2502 S.Diag(Param->getLocation(), diag::note_template_param_here);
2506 S.Diag(AddrOpLoc, diag::err_template_arg_address_of_non_pointer)
2508 << FixItHint::CreateRemoval(AddrOpLoc);
2509 S.Diag(Param->getLocation(), diag::note_template_param_here);
2511 ArgType = Func->getType();
2513 } else if (VarDecl *Var = dyn_cast<VarDecl>(DRE->getDecl())) {
2514 if (!isExternalLinkage(Var->getLinkage())) {
2515 S.Diag(Arg->getSourceRange().getBegin(),
2516 diag::err_template_arg_object_not_extern)
2517 << Var << Arg->getSourceRange();
2518 S.Diag(Var->getLocation(), diag::note_template_arg_internal_object)
2523 // A value of reference type is not an object.
2524 if (Var->getType()->isReferenceType()) {
2525 S.Diag(Arg->getSourceRange().getBegin(),
2526 diag::err_template_arg_reference_var)
2527 << Var->getType() << Arg->getSourceRange();
2528 S.Diag(Param->getLocation(), diag::note_template_param_here);
2532 // Okay: we've named an object with external linkage
2535 // If the template parameter has pointer type, we must have taken
2536 // the address of this object.
2537 if (ParamType->isReferenceType()) {
2539 // If we originally had an address-of operator, but the
2540 // parameter has reference type, complain and (if things look
2541 // like they will work) drop the address-of operator.
2542 if (!S.Context.hasSameUnqualifiedType(Var->getType(),
2543 ParamType.getNonReferenceType())) {
2544 S.Diag(AddrOpLoc, diag::err_template_arg_address_of_non_pointer)
2546 S.Diag(Param->getLocation(), diag::note_template_param_here);
2550 S.Diag(AddrOpLoc, diag::err_template_arg_address_of_non_pointer)
2552 << FixItHint::CreateRemoval(AddrOpLoc);
2553 S.Diag(Param->getLocation(), diag::note_template_param_here);
2555 ArgType = Var->getType();
2557 } else if (!AddressTaken && ParamType->isPointerType()) {
2558 if (Var->getType()->isArrayType()) {
2559 // Array-to-pointer decay.
2560 ArgType = S.Context.getArrayDecayedType(Var->getType());
2562 // If the template parameter has pointer type but the address of
2563 // this object was not taken, complain and (possibly) recover by
2564 // taking the address of the entity.
2565 ArgType = S.Context.getPointerType(Var->getType());
2566 if (!S.Context.hasSameUnqualifiedType(ArgType, ParamType)) {
2567 S.Diag(Arg->getLocStart(), diag::err_template_arg_not_address_of)
2569 S.Diag(Param->getLocation(), diag::note_template_param_here);
2573 S.Diag(Arg->getLocStart(), diag::err_template_arg_not_address_of)
2575 << FixItHint::CreateInsertion(Arg->getLocStart(), "&");
2577 S.Diag(Param->getLocation(), diag::note_template_param_here);
2581 // We found something else, but we don't know specifically what it is.
2582 S.Diag(Arg->getSourceRange().getBegin(),
2583 diag::err_template_arg_not_object_or_func)
2584 << Arg->getSourceRange();
2585 S.Diag(DRE->getDecl()->getLocation(), diag::note_template_arg_refers_here);
2589 if (ParamType->isPointerType() &&
2590 !ParamType->getAs<PointerType>()->getPointeeType()->isFunctionType() &&
2591 S.IsQualificationConversion(ArgType, ParamType)) {
2592 // For pointer-to-object types, qualification conversions are
2595 if (const ReferenceType *ParamRef = ParamType->getAs<ReferenceType>()) {
2596 if (!ParamRef->getPointeeType()->isFunctionType()) {
2597 // C++ [temp.arg.nontype]p5b3:
2598 // For a non-type template-parameter of type reference to
2599 // object, no conversions apply. The type referred to by the
2600 // reference may be more cv-qualified than the (otherwise
2601 // identical) type of the template- argument. The
2602 // template-parameter is bound directly to the
2603 // template-argument, which shall be an lvalue.
2605 // FIXME: Other qualifiers?
2606 unsigned ParamQuals = ParamRef->getPointeeType().getCVRQualifiers();
2607 unsigned ArgQuals = ArgType.getCVRQualifiers();
2609 if ((ParamQuals | ArgQuals) != ParamQuals) {
2610 S.Diag(Arg->getSourceRange().getBegin(),
2611 diag::err_template_arg_ref_bind_ignores_quals)
2612 << ParamType << Arg->getType()
2613 << Arg->getSourceRange();
2614 S.Diag(Param->getLocation(), diag::note_template_param_here);
2620 // At this point, the template argument refers to an object or
2621 // function with external linkage. We now need to check whether the
2622 // argument and parameter types are compatible.
2623 if (!S.Context.hasSameUnqualifiedType(ArgType,
2624 ParamType.getNonReferenceType())) {
2625 // We can't perform this conversion or binding.
2626 if (ParamType->isReferenceType())
2627 S.Diag(Arg->getLocStart(), diag::err_template_arg_no_ref_bind)
2628 << ParamType << Arg->getType() << Arg->getSourceRange();
2630 S.Diag(Arg->getLocStart(), diag::err_template_arg_not_convertible)
2631 << Arg->getType() << ParamType << Arg->getSourceRange();
2632 S.Diag(Param->getLocation(), diag::note_template_param_here);
2637 // Create the template argument.
2638 Converted = TemplateArgument(Entity->getCanonicalDecl());
2639 S.MarkDeclarationReferenced(Arg->getLocStart(), Entity);
2643 /// \brief Checks whether the given template argument is a pointer to
2644 /// member constant according to C++ [temp.arg.nontype]p1.
2645 bool Sema::CheckTemplateArgumentPointerToMember(Expr *Arg,
2646 TemplateArgument &Converted) {
2647 bool Invalid = false;
2649 // See through any implicit casts we added to fix the type.
2650 while (ImplicitCastExpr *Cast = dyn_cast<ImplicitCastExpr>(Arg))
2651 Arg = Cast->getSubExpr();
2653 // C++ [temp.arg.nontype]p1:
2655 // A template-argument for a non-type, non-template
2656 // template-parameter shall be one of: [...]
2658 // -- a pointer to member expressed as described in 5.3.1.
2659 DeclRefExpr *DRE = 0;
2661 // Ignore (and complain about) any excess parentheses.
2662 while (ParenExpr *Parens = dyn_cast<ParenExpr>(Arg)) {
2664 Diag(Arg->getSourceRange().getBegin(),
2665 diag::err_template_arg_extra_parens)
2666 << Arg->getSourceRange();
2670 Arg = Parens->getSubExpr();
2673 // A pointer-to-member constant written &Class::member.
2674 if (UnaryOperator *UnOp = dyn_cast<UnaryOperator>(Arg)) {
2675 if (UnOp->getOpcode() == UO_AddrOf) {
2676 DRE = dyn_cast<DeclRefExpr>(UnOp->getSubExpr());
2677 if (DRE && !DRE->getQualifier())
2681 // A constant of pointer-to-member type.
2682 else if ((DRE = dyn_cast<DeclRefExpr>(Arg))) {
2683 if (ValueDecl *VD = dyn_cast<ValueDecl>(DRE->getDecl())) {
2684 if (VD->getType()->isMemberPointerType()) {
2685 if (isa<NonTypeTemplateParmDecl>(VD) ||
2686 (isa<VarDecl>(VD) &&
2687 Context.getCanonicalType(VD->getType()).isConstQualified())) {
2688 if (Arg->isTypeDependent() || Arg->isValueDependent())
2689 Converted = TemplateArgument(Arg->Retain());
2691 Converted = TemplateArgument(VD->getCanonicalDecl());
2701 return Diag(Arg->getSourceRange().getBegin(),
2702 diag::err_template_arg_not_pointer_to_member_form)
2703 << Arg->getSourceRange();
2705 if (isa<FieldDecl>(DRE->getDecl()) || isa<CXXMethodDecl>(DRE->getDecl())) {
2706 assert((isa<FieldDecl>(DRE->getDecl()) ||
2707 !cast<CXXMethodDecl>(DRE->getDecl())->isStatic()) &&
2708 "Only non-static member pointers can make it here");
2710 // Okay: this is the address of a non-static member, and therefore
2711 // a member pointer constant.
2712 if (Arg->isTypeDependent() || Arg->isValueDependent())
2713 Converted = TemplateArgument(Arg->Retain());
2715 Converted = TemplateArgument(DRE->getDecl()->getCanonicalDecl());
2719 // We found something else, but we don't know specifically what it is.
2720 Diag(Arg->getSourceRange().getBegin(),
2721 diag::err_template_arg_not_pointer_to_member_form)
2722 << Arg->getSourceRange();
2723 Diag(DRE->getDecl()->getLocation(),
2724 diag::note_template_arg_refers_here);
2728 /// \brief Check a template argument against its corresponding
2729 /// non-type template parameter.
2731 /// This routine implements the semantics of C++ [temp.arg.nontype].
2732 /// It returns true if an error occurred, and false otherwise. \p
2733 /// InstantiatedParamType is the type of the non-type template
2734 /// parameter after it has been instantiated.
2736 /// If no error was detected, Converted receives the converted template argument.
2737 bool Sema::CheckTemplateArgument(NonTypeTemplateParmDecl *Param,
2738 QualType InstantiatedParamType, Expr *&Arg,
2739 TemplateArgument &Converted,
2740 CheckTemplateArgumentKind CTAK) {
2741 SourceLocation StartLoc = Arg->getSourceRange().getBegin();
2743 // If either the parameter has a dependent type or the argument is
2744 // type-dependent, there's nothing we can check now.
2745 if (InstantiatedParamType->isDependentType() || Arg->isTypeDependent()) {
2746 // FIXME: Produce a cloned, canonical expression?
2747 Converted = TemplateArgument(Arg);
2751 // C++ [temp.arg.nontype]p5:
2752 // The following conversions are performed on each expression used
2753 // as a non-type template-argument. If a non-type
2754 // template-argument cannot be converted to the type of the
2755 // corresponding template-parameter then the program is
2758 // -- for a non-type template-parameter of integral or
2759 // enumeration type, integral promotions (4.5) and integral
2760 // conversions (4.7) are applied.
2761 QualType ParamType = InstantiatedParamType;
2762 QualType ArgType = Arg->getType();
2763 if (ParamType->isIntegralOrEnumerationType()) {
2764 // C++ [temp.arg.nontype]p1:
2765 // A template-argument for a non-type, non-template
2766 // template-parameter shall be one of:
2768 // -- an integral constant-expression of integral or enumeration
2770 // -- the name of a non-type template-parameter; or
2771 SourceLocation NonConstantLoc;
2773 if (!ArgType->isIntegralOrEnumerationType()) {
2774 Diag(Arg->getSourceRange().getBegin(),
2775 diag::err_template_arg_not_integral_or_enumeral)
2776 << ArgType << Arg->getSourceRange();
2777 Diag(Param->getLocation(), diag::note_template_param_here);
2779 } else if (!Arg->isValueDependent() &&
2780 !Arg->isIntegerConstantExpr(Value, Context, &NonConstantLoc)) {
2781 Diag(NonConstantLoc, diag::err_template_arg_not_ice)
2782 << ArgType << Arg->getSourceRange();
2786 // From here on out, all we care about are the unqualified forms
2787 // of the parameter and argument types.
2788 ParamType = ParamType.getUnqualifiedType();
2789 ArgType = ArgType.getUnqualifiedType();
2791 // Try to convert the argument to the parameter's type.
2792 if (Context.hasSameType(ParamType, ArgType)) {
2793 // Okay: no conversion necessary
2794 } else if (CTAK == CTAK_Deduced) {
2795 // C++ [temp.deduct.type]p17:
2796 // If, in the declaration of a function template with a non-type
2797 // template-parameter, the non-type template- parameter is used
2798 // in an expression in the function parameter-list and, if the
2799 // corresponding template-argument is deduced, the
2800 // template-argument type shall match the type of the
2801 // template-parameter exactly, except that a template-argument
2802 // deduced from an array bound may be of any integral type.
2803 Diag(StartLoc, diag::err_deduced_non_type_template_arg_type_mismatch)
2804 << ArgType << ParamType;
2805 Diag(Param->getLocation(), diag::note_template_param_here);
2807 } else if (IsIntegralPromotion(Arg, ArgType, ParamType) ||
2808 !ParamType->isEnumeralType()) {
2809 // This is an integral promotion or conversion.
2810 ImpCastExprToType(Arg, ParamType, CK_IntegralCast);
2812 // We can't perform this conversion.
2813 Diag(Arg->getSourceRange().getBegin(),
2814 diag::err_template_arg_not_convertible)
2815 << Arg->getType() << InstantiatedParamType << Arg->getSourceRange();
2816 Diag(Param->getLocation(), diag::note_template_param_here);
2820 QualType IntegerType = Context.getCanonicalType(ParamType);
2821 if (const EnumType *Enum = IntegerType->getAs<EnumType>())
2822 IntegerType = Context.getCanonicalType(Enum->getDecl()->getIntegerType());
2824 if (!Arg->isValueDependent()) {
2825 llvm::APSInt OldValue = Value;
2827 // Coerce the template argument's value to the value it will have
2828 // based on the template parameter's type.
2829 unsigned AllowedBits = Context.getTypeSize(IntegerType);
2830 if (Value.getBitWidth() != AllowedBits)
2831 Value.extOrTrunc(AllowedBits);
2832 Value.setIsSigned(IntegerType->isSignedIntegerType());
2834 // Complain if an unsigned parameter received a negative value.
2835 if (IntegerType->isUnsignedIntegerType()
2836 && (OldValue.isSigned() && OldValue.isNegative())) {
2837 Diag(Arg->getSourceRange().getBegin(), diag::warn_template_arg_negative)
2838 << OldValue.toString(10) << Value.toString(10) << Param->getType()
2839 << Arg->getSourceRange();
2840 Diag(Param->getLocation(), diag::note_template_param_here);
2843 // Complain if we overflowed the template parameter's type.
2844 unsigned RequiredBits;
2845 if (IntegerType->isUnsignedIntegerType())
2846 RequiredBits = OldValue.getActiveBits();
2847 else if (OldValue.isUnsigned())
2848 RequiredBits = OldValue.getActiveBits() + 1;
2850 RequiredBits = OldValue.getMinSignedBits();
2851 if (RequiredBits > AllowedBits) {
2852 Diag(Arg->getSourceRange().getBegin(),
2853 diag::warn_template_arg_too_large)
2854 << OldValue.toString(10) << Value.toString(10) << Param->getType()
2855 << Arg->getSourceRange();
2856 Diag(Param->getLocation(), diag::note_template_param_here);
2860 // Add the value of this argument to the list of converted
2861 // arguments. We use the bitwidth and signedness of the template
2863 if (Arg->isValueDependent()) {
2864 // The argument is value-dependent. Create a new
2865 // TemplateArgument with the converted expression.
2866 Converted = TemplateArgument(Arg);
2870 Converted = TemplateArgument(Value,
2871 ParamType->isEnumeralType() ? ParamType
2876 DeclAccessPair FoundResult; // temporary for ResolveOverloadedFunction
2878 // C++0x [temp.arg.nontype]p5 bullets 2, 4 and 6 permit conversion
2879 // from a template argument of type std::nullptr_t to a non-type
2880 // template parameter of type pointer to object, pointer to
2881 // function, or pointer-to-member, respectively.
2882 if (ArgType->isNullPtrType() &&
2883 (ParamType->isPointerType() || ParamType->isMemberPointerType())) {
2884 Converted = TemplateArgument((NamedDecl *)0);
2888 // Handle pointer-to-function, reference-to-function, and
2889 // pointer-to-member-function all in (roughly) the same way.
2890 if (// -- For a non-type template-parameter of type pointer to
2891 // function, only the function-to-pointer conversion (4.3) is
2892 // applied. If the template-argument represents a set of
2893 // overloaded functions (or a pointer to such), the matching
2894 // function is selected from the set (13.4).
2895 (ParamType->isPointerType() &&
2896 ParamType->getAs<PointerType>()->getPointeeType()->isFunctionType()) ||
2897 // -- For a non-type template-parameter of type reference to
2898 // function, no conversions apply. If the template-argument
2899 // represents a set of overloaded functions, the matching
2900 // function is selected from the set (13.4).
2901 (ParamType->isReferenceType() &&
2902 ParamType->getAs<ReferenceType>()->getPointeeType()->isFunctionType()) ||
2903 // -- For a non-type template-parameter of type pointer to
2904 // member function, no conversions apply. If the
2905 // template-argument represents a set of overloaded member
2906 // functions, the matching member function is selected from
2908 (ParamType->isMemberPointerType() &&
2909 ParamType->getAs<MemberPointerType>()->getPointeeType()
2910 ->isFunctionType())) {
2912 if (Arg->getType() == Context.OverloadTy) {
2913 if (FunctionDecl *Fn = ResolveAddressOfOverloadedFunction(Arg, ParamType,
2916 if (DiagnoseUseOfDecl(Fn, Arg->getSourceRange().getBegin()))
2919 Arg = FixOverloadedFunctionReference(Arg, FoundResult, Fn);
2920 ArgType = Arg->getType();
2925 if (!ParamType->isMemberPointerType())
2926 return CheckTemplateArgumentAddressOfObjectOrFunction(*this, Param,
2930 if (IsQualificationConversion(ArgType, ParamType.getNonReferenceType())) {
2931 ImpCastExprToType(Arg, ParamType, CK_NoOp, CastCategory(Arg));
2932 } else if (!Context.hasSameUnqualifiedType(ArgType,
2933 ParamType.getNonReferenceType())) {
2934 // We can't perform this conversion.
2935 Diag(Arg->getSourceRange().getBegin(),
2936 diag::err_template_arg_not_convertible)
2937 << Arg->getType() << InstantiatedParamType << Arg->getSourceRange();
2938 Diag(Param->getLocation(), diag::note_template_param_here);
2942 return CheckTemplateArgumentPointerToMember(Arg, Converted);
2945 if (ParamType->isPointerType()) {
2946 // -- for a non-type template-parameter of type pointer to
2947 // object, qualification conversions (4.4) and the
2948 // array-to-pointer conversion (4.2) are applied.
2949 // C++0x also allows a value of std::nullptr_t.
2950 assert(ParamType->getPointeeType()->isIncompleteOrObjectType() &&
2951 "Only object pointers allowed here");
2953 return CheckTemplateArgumentAddressOfObjectOrFunction(*this, Param,
2958 if (const ReferenceType *ParamRefType = ParamType->getAs<ReferenceType>()) {
2959 // -- For a non-type template-parameter of type reference to
2960 // object, no conversions apply. The type referred to by the
2961 // reference may be more cv-qualified than the (otherwise
2962 // identical) type of the template-argument. The
2963 // template-parameter is bound directly to the
2964 // template-argument, which must be an lvalue.
2965 assert(ParamRefType->getPointeeType()->isIncompleteOrObjectType() &&
2966 "Only object references allowed here");
2968 if (Arg->getType() == Context.OverloadTy) {
2969 if (FunctionDecl *Fn = ResolveAddressOfOverloadedFunction(Arg,
2970 ParamRefType->getPointeeType(),
2973 if (DiagnoseUseOfDecl(Fn, Arg->getSourceRange().getBegin()))
2976 Arg = FixOverloadedFunctionReference(Arg, FoundResult, Fn);
2977 ArgType = Arg->getType();
2982 return CheckTemplateArgumentAddressOfObjectOrFunction(*this, Param,
2987 // -- For a non-type template-parameter of type pointer to data
2988 // member, qualification conversions (4.4) are applied.
2989 assert(ParamType->isMemberPointerType() && "Only pointers to members remain");
2991 if (Context.hasSameUnqualifiedType(ParamType, ArgType)) {
2992 // Types match exactly: nothing more to do here.
2993 } else if (IsQualificationConversion(ArgType, ParamType)) {
2994 ImpCastExprToType(Arg, ParamType, CK_NoOp, CastCategory(Arg));
2996 // We can't perform this conversion.
2997 Diag(Arg->getSourceRange().getBegin(),
2998 diag::err_template_arg_not_convertible)
2999 << Arg->getType() << InstantiatedParamType << Arg->getSourceRange();
3000 Diag(Param->getLocation(), diag::note_template_param_here);
3004 return CheckTemplateArgumentPointerToMember(Arg, Converted);
3007 /// \brief Check a template argument against its corresponding
3008 /// template template parameter.
3010 /// This routine implements the semantics of C++ [temp.arg.template].
3011 /// It returns true if an error occurred, and false otherwise.
3012 bool Sema::CheckTemplateArgument(TemplateTemplateParmDecl *Param,
3013 const TemplateArgumentLoc &Arg) {
3014 TemplateName Name = Arg.getArgument().getAsTemplate();
3015 TemplateDecl *Template = Name.getAsTemplateDecl();
3017 // Any dependent template name is fine.
3018 assert(Name.isDependent() && "Non-dependent template isn't a declaration?");
3022 // C++ [temp.arg.template]p1:
3023 // A template-argument for a template template-parameter shall be
3024 // the name of a class template, expressed as id-expression. Only
3025 // primary class templates are considered when matching the
3026 // template template argument with the corresponding parameter;
3027 // partial specializations are not considered even if their
3028 // parameter lists match that of the template template parameter.
3030 // Note that we also allow template template parameters here, which
3031 // will happen when we are dealing with, e.g., class template
3032 // partial specializations.
3033 if (!isa<ClassTemplateDecl>(Template) &&
3034 !isa<TemplateTemplateParmDecl>(Template)) {
3035 assert(isa<FunctionTemplateDecl>(Template) &&
3036 "Only function templates are possible here");
3037 Diag(Arg.getLocation(), diag::err_template_arg_not_class_template);
3038 Diag(Template->getLocation(), diag::note_template_arg_refers_here_func)
3042 return !TemplateParameterListsAreEqual(Template->getTemplateParameters(),
3043 Param->getTemplateParameters(),
3045 TPL_TemplateTemplateArgumentMatch,
3049 /// \brief Given a non-type template argument that refers to a
3050 /// declaration and the type of its corresponding non-type template
3051 /// parameter, produce an expression that properly refers to that
3054 Sema::BuildExpressionFromDeclTemplateArgument(const TemplateArgument &Arg,
3056 SourceLocation Loc) {
3057 assert(Arg.getKind() == TemplateArgument::Declaration &&
3058 "Only declaration template arguments permitted here");
3059 ValueDecl *VD = cast<ValueDecl>(Arg.getAsDecl());
3061 if (VD->getDeclContext()->isRecord() &&
3062 (isa<CXXMethodDecl>(VD) || isa<FieldDecl>(VD))) {
3063 // If the value is a class member, we might have a pointer-to-member.
3064 // Determine whether the non-type template template parameter is of
3065 // pointer-to-member type. If so, we need to build an appropriate
3066 // expression for a pointer-to-member, since a "normal" DeclRefExpr
3067 // would refer to the member itself.
3068 if (ParamType->isMemberPointerType()) {
3070 = Context.getTypeDeclType(cast<RecordDecl>(VD->getDeclContext()));
3071 NestedNameSpecifier *Qualifier
3072 = NestedNameSpecifier::Create(Context, 0, false,
3073 ClassType.getTypePtr());
3075 SS.setScopeRep(Qualifier);
3076 ExprResult RefExpr = BuildDeclRefExpr(VD,
3077 VD->getType().getNonReferenceType(),
3080 if (RefExpr.isInvalid())
3083 RefExpr = CreateBuiltinUnaryOp(Loc, UO_AddrOf, RefExpr.get());
3085 // We might need to perform a trailing qualification conversion, since
3086 // the element type on the parameter could be more qualified than the
3087 // element type in the expression we constructed.
3088 if (IsQualificationConversion(((Expr*) RefExpr.get())->getType(),
3089 ParamType.getUnqualifiedType())) {
3090 Expr *RefE = RefExpr.takeAs<Expr>();
3091 ImpCastExprToType(RefE, ParamType.getUnqualifiedType(), CK_NoOp);
3092 RefExpr = Owned(RefE);
3095 assert(!RefExpr.isInvalid() &&
3096 Context.hasSameType(((Expr*) RefExpr.get())->getType(),
3097 ParamType.getUnqualifiedType()));
3098 return move(RefExpr);
3102 QualType T = VD->getType().getNonReferenceType();
3103 if (ParamType->isPointerType()) {
3104 // When the non-type template parameter is a pointer, take the
3105 // address of the declaration.
3106 ExprResult RefExpr = BuildDeclRefExpr(VD, T, Loc);
3107 if (RefExpr.isInvalid())
3110 if (T->isFunctionType() || T->isArrayType()) {
3111 // Decay functions and arrays.
3112 Expr *RefE = (Expr *)RefExpr.get();
3113 DefaultFunctionArrayConversion(RefE);
3114 if (RefE != RefExpr.get()) {
3116 RefExpr = Owned(RefE);
3119 return move(RefExpr);
3122 // Take the address of everything else
3123 return CreateBuiltinUnaryOp(Loc, UO_AddrOf, RefExpr.get());
3126 // If the non-type template parameter has reference type, qualify the
3127 // resulting declaration reference with the extra qualifiers on the
3128 // type that the reference refers to.
3129 if (const ReferenceType *TargetRef = ParamType->getAs<ReferenceType>())
3130 T = Context.getQualifiedType(T, TargetRef->getPointeeType().getQualifiers());
3132 return BuildDeclRefExpr(VD, T, Loc);
3135 /// \brief Construct a new expression that refers to the given
3136 /// integral template argument with the given source-location
3139 /// This routine takes care of the mapping from an integral template
3140 /// argument (which may have any integral type) to the appropriate
3143 Sema::BuildExpressionFromIntegralTemplateArgument(const TemplateArgument &Arg,
3144 SourceLocation Loc) {
3145 assert(Arg.getKind() == TemplateArgument::Integral &&
3146 "Operation is only value for integral template arguments");
3147 QualType T = Arg.getIntegralType();
3148 if (T->isCharType() || T->isWideCharType())
3149 return Owned(new (Context) CharacterLiteral(
3150 Arg.getAsIntegral()->getZExtValue(),
3151 T->isWideCharType(),
3154 if (T->isBooleanType())
3155 return Owned(new (Context) CXXBoolLiteralExpr(
3156 Arg.getAsIntegral()->getBoolValue(),
3160 return Owned(IntegerLiteral::Create(Context, *Arg.getAsIntegral(), T, Loc));
3164 /// \brief Determine whether the given template parameter lists are
3167 /// \param New The new template parameter list, typically written in the
3168 /// source code as part of a new template declaration.
3170 /// \param Old The old template parameter list, typically found via
3171 /// name lookup of the template declared with this template parameter
3174 /// \param Complain If true, this routine will produce a diagnostic if
3175 /// the template parameter lists are not equivalent.
3177 /// \param Kind describes how we are to match the template parameter lists.
3179 /// \param TemplateArgLoc If this source location is valid, then we
3180 /// are actually checking the template parameter list of a template
3181 /// argument (New) against the template parameter list of its
3182 /// corresponding template template parameter (Old). We produce
3183 /// slightly different diagnostics in this scenario.
3185 /// \returns True if the template parameter lists are equal, false
3188 Sema::TemplateParameterListsAreEqual(TemplateParameterList *New,
3189 TemplateParameterList *Old,
3191 TemplateParameterListEqualKind Kind,
3192 SourceLocation TemplateArgLoc) {
3193 if (Old->size() != New->size()) {
3195 unsigned NextDiag = diag::err_template_param_list_different_arity;
3196 if (TemplateArgLoc.isValid()) {
3197 Diag(TemplateArgLoc, diag::err_template_arg_template_params_mismatch);
3198 NextDiag = diag::note_template_param_list_different_arity;
3200 Diag(New->getTemplateLoc(), NextDiag)
3201 << (New->size() > Old->size())
3202 << (Kind != TPL_TemplateMatch)
3203 << SourceRange(New->getTemplateLoc(), New->getRAngleLoc());
3204 Diag(Old->getTemplateLoc(), diag::note_template_prev_declaration)
3205 << (Kind != TPL_TemplateMatch)
3206 << SourceRange(Old->getTemplateLoc(), Old->getRAngleLoc());
3212 for (TemplateParameterList::iterator OldParm = Old->begin(),
3213 OldParmEnd = Old->end(), NewParm = New->begin();
3214 OldParm != OldParmEnd; ++OldParm, ++NewParm) {
3215 if ((*OldParm)->getKind() != (*NewParm)->getKind()) {
3217 unsigned NextDiag = diag::err_template_param_different_kind;
3218 if (TemplateArgLoc.isValid()) {
3219 Diag(TemplateArgLoc, diag::err_template_arg_template_params_mismatch);
3220 NextDiag = diag::note_template_param_different_kind;
3222 Diag((*NewParm)->getLocation(), NextDiag)
3223 << (Kind != TPL_TemplateMatch);
3224 Diag((*OldParm)->getLocation(), diag::note_template_prev_declaration)
3225 << (Kind != TPL_TemplateMatch);
3230 if (TemplateTypeParmDecl *OldTTP
3231 = dyn_cast<TemplateTypeParmDecl>(*OldParm)) {
3232 // Template type parameters are equivalent if either both are template
3233 // type parameter packs or neither are (since we know we're at the same
3235 TemplateTypeParmDecl *NewTTP = cast<TemplateTypeParmDecl>(*NewParm);
3236 if (OldTTP->isParameterPack() != NewTTP->isParameterPack()) {
3237 // FIXME: Implement the rules in C++0x [temp.arg.template]p5 that
3238 // allow one to match a template parameter pack in the template
3239 // parameter list of a template template parameter to one or more
3240 // template parameters in the template parameter list of the
3241 // corresponding template template argument.
3243 unsigned NextDiag = diag::err_template_parameter_pack_non_pack;
3244 if (TemplateArgLoc.isValid()) {
3245 Diag(TemplateArgLoc,
3246 diag::err_template_arg_template_params_mismatch);
3247 NextDiag = diag::note_template_parameter_pack_non_pack;
3249 Diag(NewTTP->getLocation(), NextDiag)
3250 << 0 << NewTTP->isParameterPack();
3251 Diag(OldTTP->getLocation(), diag::note_template_parameter_pack_here)
3252 << 0 << OldTTP->isParameterPack();
3256 } else if (NonTypeTemplateParmDecl *OldNTTP
3257 = dyn_cast<NonTypeTemplateParmDecl>(*OldParm)) {
3258 // The types of non-type template parameters must agree.
3259 NonTypeTemplateParmDecl *NewNTTP
3260 = cast<NonTypeTemplateParmDecl>(*NewParm);
3262 // If we are matching a template template argument to a template
3263 // template parameter and one of the non-type template parameter types
3264 // is dependent, then we must wait until template instantiation time
3265 // to actually compare the arguments.
3266 if (Kind == TPL_TemplateTemplateArgumentMatch &&
3267 (OldNTTP->getType()->isDependentType() ||
3268 NewNTTP->getType()->isDependentType()))
3271 if (Context.getCanonicalType(OldNTTP->getType()) !=
3272 Context.getCanonicalType(NewNTTP->getType())) {
3274 unsigned NextDiag = diag::err_template_nontype_parm_different_type;
3275 if (TemplateArgLoc.isValid()) {
3276 Diag(TemplateArgLoc,
3277 diag::err_template_arg_template_params_mismatch);
3278 NextDiag = diag::note_template_nontype_parm_different_type;
3280 Diag(NewNTTP->getLocation(), NextDiag)
3281 << NewNTTP->getType()
3282 << (Kind != TPL_TemplateMatch);
3283 Diag(OldNTTP->getLocation(),
3284 diag::note_template_nontype_parm_prev_declaration)
3285 << OldNTTP->getType();
3290 // The template parameter lists of template template
3291 // parameters must agree.
3292 assert(isa<TemplateTemplateParmDecl>(*OldParm) &&
3293 "Only template template parameters handled here");
3294 TemplateTemplateParmDecl *OldTTP
3295 = cast<TemplateTemplateParmDecl>(*OldParm);
3296 TemplateTemplateParmDecl *NewTTP
3297 = cast<TemplateTemplateParmDecl>(*NewParm);
3298 if (!TemplateParameterListsAreEqual(NewTTP->getTemplateParameters(),
3299 OldTTP->getTemplateParameters(),
3301 (Kind == TPL_TemplateMatch? TPL_TemplateTemplateParmMatch : Kind),
3310 /// \brief Check whether a template can be declared within this scope.
3312 /// If the template declaration is valid in this scope, returns
3313 /// false. Otherwise, issues a diagnostic and returns true.
3315 Sema::CheckTemplateDeclScope(Scope *S, TemplateParameterList *TemplateParams) {
3316 // Find the nearest enclosing declaration scope.
3317 while ((S->getFlags() & Scope::DeclScope) == 0 ||
3318 (S->getFlags() & Scope::TemplateParamScope) != 0)
3322 // A template-declaration can appear only as a namespace scope or
3323 // class scope declaration.
3324 DeclContext *Ctx = static_cast<DeclContext *>(S->getEntity());
3325 if (Ctx && isa<LinkageSpecDecl>(Ctx) &&
3326 cast<LinkageSpecDecl>(Ctx)->getLanguage() != LinkageSpecDecl::lang_cxx)
3327 return Diag(TemplateParams->getTemplateLoc(), diag::err_template_linkage)
3328 << TemplateParams->getSourceRange();
3330 while (Ctx && isa<LinkageSpecDecl>(Ctx))
3331 Ctx = Ctx->getParent();
3333 if (Ctx && (Ctx->isFileContext() || Ctx->isRecord()))
3336 return Diag(TemplateParams->getTemplateLoc(),
3337 diag::err_template_outside_namespace_or_class_scope)
3338 << TemplateParams->getSourceRange();
3341 /// \brief Determine what kind of template specialization the given declaration
3343 static TemplateSpecializationKind getTemplateSpecializationKind(NamedDecl *D) {
3345 return TSK_Undeclared;
3347 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(D))
3348 return Record->getTemplateSpecializationKind();
3349 if (FunctionDecl *Function = dyn_cast<FunctionDecl>(D))
3350 return Function->getTemplateSpecializationKind();
3351 if (VarDecl *Var = dyn_cast<VarDecl>(D))
3352 return Var->getTemplateSpecializationKind();
3354 return TSK_Undeclared;
3357 /// \brief Check whether a specialization is well-formed in the current
3360 /// This routine determines whether a template specialization can be declared
3361 /// in the current context (C++ [temp.expl.spec]p2).
3363 /// \param S the semantic analysis object for which this check is being
3366 /// \param Specialized the entity being specialized or instantiated, which
3367 /// may be a kind of template (class template, function template, etc.) or
3368 /// a member of a class template (member function, static data member,
3371 /// \param PrevDecl the previous declaration of this entity, if any.
3373 /// \param Loc the location of the explicit specialization or instantiation of
3376 /// \param IsPartialSpecialization whether this is a partial specialization of
3377 /// a class template.
3379 /// \returns true if there was an error that we cannot recover from, false
3381 static bool CheckTemplateSpecializationScope(Sema &S,
3382 NamedDecl *Specialized,
3383 NamedDecl *PrevDecl,
3385 bool IsPartialSpecialization) {
3386 // Keep these "kind" numbers in sync with the %select statements in the
3387 // various diagnostics emitted by this routine.
3389 bool isTemplateSpecialization = false;
3390 if (isa<ClassTemplateDecl>(Specialized)) {
3391 EntityKind = IsPartialSpecialization? 1 : 0;
3392 isTemplateSpecialization = true;
3393 } else if (isa<FunctionTemplateDecl>(Specialized)) {
3395 isTemplateSpecialization = true;
3396 } else if (isa<CXXMethodDecl>(Specialized))
3398 else if (isa<VarDecl>(Specialized))
3400 else if (isa<RecordDecl>(Specialized))
3403 S.Diag(Loc, diag::err_template_spec_unknown_kind);
3404 S.Diag(Specialized->getLocation(), diag::note_specialized_entity);
3408 // C++ [temp.expl.spec]p2:
3409 // An explicit specialization shall be declared in the namespace
3410 // of which the template is a member, or, for member templates, in
3411 // the namespace of which the enclosing class or enclosing class
3412 // template is a member. An explicit specialization of a member
3413 // function, member class or static data member of a class
3414 // template shall be declared in the namespace of which the class
3415 // template is a member. Such a declaration may also be a
3416 // definition. If the declaration is not a definition, the
3417 // specialization may be defined later in the name- space in which
3418 // the explicit specialization was declared, or in a namespace
3419 // that encloses the one in which the explicit specialization was
3421 if (S.CurContext->getRedeclContext()->isFunctionOrMethod()) {
3422 S.Diag(Loc, diag::err_template_spec_decl_function_scope)
3427 if (S.CurContext->isRecord() && !IsPartialSpecialization) {
3428 S.Diag(Loc, diag::err_template_spec_decl_class_scope)
3433 // C++ [temp.class.spec]p6:
3434 // A class template partial specialization may be declared or redeclared
3435 // in any namespace scope in which its definition may be defined (14.5.1
3437 bool ComplainedAboutScope = false;
3438 DeclContext *SpecializedContext
3439 = Specialized->getDeclContext()->getEnclosingNamespaceContext();
3440 DeclContext *DC = S.CurContext->getEnclosingNamespaceContext();
3442 getTemplateSpecializationKind(PrevDecl) == TSK_Undeclared ||
3443 getTemplateSpecializationKind(PrevDecl) == TSK_ImplicitInstantiation)){
3444 // There is no prior declaration of this entity, so this
3445 // specialization must be in the same context as the template
3446 // itself, or in the enclosing namespace set.
3447 if (!DC->InEnclosingNamespaceSetOf(SpecializedContext)) {
3448 if (isa<TranslationUnitDecl>(SpecializedContext))
3449 S.Diag(Loc, diag::err_template_spec_decl_out_of_scope_global)
3450 << EntityKind << Specialized;
3451 else if (isa<NamespaceDecl>(SpecializedContext))
3452 S.Diag(Loc, diag::err_template_spec_decl_out_of_scope)
3453 << EntityKind << Specialized
3454 << cast<NamedDecl>(SpecializedContext);
3456 S.Diag(Specialized->getLocation(), diag::note_specialized_entity);
3457 ComplainedAboutScope = true;
3461 // Make sure that this redeclaration (or definition) occurs in an enclosing
3463 // Note that HandleDeclarator() performs this check for explicit
3464 // specializations of function templates, static data members, and member
3465 // functions, so we skip the check here for those kinds of entities.
3466 // FIXME: HandleDeclarator's diagnostics aren't quite as good, though.
3467 // Should we refactor that check, so that it occurs later?
3468 if (!ComplainedAboutScope && !DC->Encloses(SpecializedContext) &&
3469 !(isa<FunctionTemplateDecl>(Specialized) || isa<VarDecl>(Specialized) ||
3470 isa<FunctionDecl>(Specialized))) {
3471 if (isa<TranslationUnitDecl>(SpecializedContext))
3472 S.Diag(Loc, diag::err_template_spec_redecl_global_scope)
3473 << EntityKind << Specialized;
3474 else if (isa<NamespaceDecl>(SpecializedContext))
3475 S.Diag(Loc, diag::err_template_spec_redecl_out_of_scope)
3476 << EntityKind << Specialized
3477 << cast<NamedDecl>(SpecializedContext);
3479 S.Diag(Specialized->getLocation(), diag::note_specialized_entity);
3482 // FIXME: check for specialization-after-instantiation errors and such.
3487 /// \brief Check the non-type template arguments of a class template
3488 /// partial specialization according to C++ [temp.class.spec]p9.
3490 /// \param TemplateParams the template parameters of the primary class
3493 /// \param TemplateArg the template arguments of the class template
3494 /// partial specialization.
3496 /// \param MirrorsPrimaryTemplate will be set true if the class
3497 /// template partial specialization arguments are identical to the
3498 /// implicit template arguments of the primary template. This is not
3499 /// necessarily an error (C++0x), and it is left to the caller to diagnose
3500 /// this condition when it is an error.
3502 /// \returns true if there was an error, false otherwise.
3503 bool Sema::CheckClassTemplatePartialSpecializationArgs(
3504 TemplateParameterList *TemplateParams,
3505 const TemplateArgumentListBuilder &TemplateArgs,
3506 bool &MirrorsPrimaryTemplate) {
3507 // FIXME: the interface to this function will have to change to
3508 // accommodate variadic templates.
3509 MirrorsPrimaryTemplate = true;
3511 const TemplateArgument *ArgList = TemplateArgs.getFlatArguments();
3513 for (unsigned I = 0, N = TemplateParams->size(); I != N; ++I) {
3514 // Determine whether the template argument list of the partial
3515 // specialization is identical to the implicit argument list of
3516 // the primary template. The caller may need to diagnostic this as
3517 // an error per C++ [temp.class.spec]p9b3.
3518 if (MirrorsPrimaryTemplate) {
3519 if (TemplateTypeParmDecl *TTP
3520 = dyn_cast<TemplateTypeParmDecl>(TemplateParams->getParam(I))) {
3521 if (Context.getCanonicalType(Context.getTypeDeclType(TTP)) !=
3522 Context.getCanonicalType(ArgList[I].getAsType()))
3523 MirrorsPrimaryTemplate = false;
3524 } else if (TemplateTemplateParmDecl *TTP
3525 = dyn_cast<TemplateTemplateParmDecl>(
3526 TemplateParams->getParam(I))) {
3527 TemplateName Name = ArgList[I].getAsTemplate();
3528 TemplateTemplateParmDecl *ArgDecl
3529 = dyn_cast_or_null<TemplateTemplateParmDecl>(Name.getAsTemplateDecl());
3531 ArgDecl->getIndex() != TTP->getIndex() ||
3532 ArgDecl->getDepth() != TTP->getDepth())
3533 MirrorsPrimaryTemplate = false;
3537 NonTypeTemplateParmDecl *Param
3538 = dyn_cast<NonTypeTemplateParmDecl>(TemplateParams->getParam(I));
3543 Expr *ArgExpr = ArgList[I].getAsExpr();
3545 MirrorsPrimaryTemplate = false;
3549 // C++ [temp.class.spec]p8:
3550 // A non-type argument is non-specialized if it is the name of a
3551 // non-type parameter. All other non-type arguments are
3554 // Below, we check the two conditions that only apply to
3555 // specialized non-type arguments, so skip any non-specialized
3557 if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(ArgExpr))
3558 if (NonTypeTemplateParmDecl *NTTP
3559 = dyn_cast<NonTypeTemplateParmDecl>(DRE->getDecl())) {
3560 if (MirrorsPrimaryTemplate &&
3561 (Param->getIndex() != NTTP->getIndex() ||
3562 Param->getDepth() != NTTP->getDepth()))
3563 MirrorsPrimaryTemplate = false;
3568 // C++ [temp.class.spec]p9:
3569 // Within the argument list of a class template partial
3570 // specialization, the following restrictions apply:
3571 // -- A partially specialized non-type argument expression
3572 // shall not involve a template parameter of the partial
3573 // specialization except when the argument expression is a
3574 // simple identifier.
3575 if (ArgExpr->isTypeDependent() || ArgExpr->isValueDependent()) {
3576 Diag(ArgExpr->getLocStart(),
3577 diag::err_dependent_non_type_arg_in_partial_spec)
3578 << ArgExpr->getSourceRange();
3582 // -- The type of a template parameter corresponding to a
3583 // specialized non-type argument shall not be dependent on a
3584 // parameter of the specialization.
3585 if (Param->getType()->isDependentType()) {
3586 Diag(ArgExpr->getLocStart(),
3587 diag::err_dependent_typed_non_type_arg_in_partial_spec)
3589 << ArgExpr->getSourceRange();
3590 Diag(Param->getLocation(), diag::note_template_param_here);
3594 MirrorsPrimaryTemplate = false;
3600 /// \brief Retrieve the previous declaration of the given declaration.
3601 static NamedDecl *getPreviousDecl(NamedDecl *ND) {
3602 if (VarDecl *VD = dyn_cast<VarDecl>(ND))
3603 return VD->getPreviousDeclaration();
3604 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(ND))
3605 return FD->getPreviousDeclaration();
3606 if (TagDecl *TD = dyn_cast<TagDecl>(ND))
3607 return TD->getPreviousDeclaration();
3608 if (TypedefDecl *TD = dyn_cast<TypedefDecl>(ND))
3609 return TD->getPreviousDeclaration();
3610 if (FunctionTemplateDecl *FTD = dyn_cast<FunctionTemplateDecl>(ND))
3611 return FTD->getPreviousDeclaration();
3612 if (ClassTemplateDecl *CTD = dyn_cast<ClassTemplateDecl>(ND))
3613 return CTD->getPreviousDeclaration();
3618 Sema::ActOnClassTemplateSpecialization(Scope *S, unsigned TagSpec,
3620 SourceLocation KWLoc,
3622 TemplateTy TemplateD,
3623 SourceLocation TemplateNameLoc,
3624 SourceLocation LAngleLoc,
3625 ASTTemplateArgsPtr TemplateArgsIn,
3626 SourceLocation RAngleLoc,
3627 AttributeList *Attr,
3628 MultiTemplateParamsArg TemplateParameterLists) {
3629 assert(TUK != TUK_Reference && "References are not specializations");
3631 // Find the class template we're specializing
3632 TemplateName Name = TemplateD.getAsVal<TemplateName>();
3633 ClassTemplateDecl *ClassTemplate
3634 = dyn_cast_or_null<ClassTemplateDecl>(Name.getAsTemplateDecl());
3636 if (!ClassTemplate) {
3637 Diag(TemplateNameLoc, diag::err_not_class_template_specialization)
3638 << (Name.getAsTemplateDecl() &&
3639 isa<TemplateTemplateParmDecl>(Name.getAsTemplateDecl()));
3643 bool isExplicitSpecialization = false;
3644 bool isPartialSpecialization = false;
3646 // Check the validity of the template headers that introduce this
3648 // FIXME: We probably shouldn't complain about these headers for
3649 // friend declarations.
3650 bool Invalid = false;
3651 TemplateParameterList *TemplateParams
3652 = MatchTemplateParametersToScopeSpecifier(TemplateNameLoc, SS,
3653 (TemplateParameterList**)TemplateParameterLists.get(),
3654 TemplateParameterLists.size(),
3656 isExplicitSpecialization,
3661 unsigned NumMatchedTemplateParamLists = TemplateParameterLists.size();
3663 --NumMatchedTemplateParamLists;
3665 if (TemplateParams && TemplateParams->size() > 0) {
3666 isPartialSpecialization = true;
3668 // C++ [temp.class.spec]p10:
3669 // The template parameter list of a specialization shall not
3670 // contain default template argument values.
3671 for (unsigned I = 0, N = TemplateParams->size(); I != N; ++I) {
3672 Decl *Param = TemplateParams->getParam(I);
3673 if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(Param)) {
3674 if (TTP->hasDefaultArgument()) {
3675 Diag(TTP->getDefaultArgumentLoc(),
3676 diag::err_default_arg_in_partial_spec);
3677 TTP->removeDefaultArgument();
3679 } else if (NonTypeTemplateParmDecl *NTTP
3680 = dyn_cast<NonTypeTemplateParmDecl>(Param)) {
3681 if (Expr *DefArg = NTTP->getDefaultArgument()) {
3682 Diag(NTTP->getDefaultArgumentLoc(),
3683 diag::err_default_arg_in_partial_spec)
3684 << DefArg->getSourceRange();
3685 NTTP->removeDefaultArgument();
3688 TemplateTemplateParmDecl *TTP = cast<TemplateTemplateParmDecl>(Param);
3689 if (TTP->hasDefaultArgument()) {
3690 Diag(TTP->getDefaultArgument().getLocation(),
3691 diag::err_default_arg_in_partial_spec)
3692 << TTP->getDefaultArgument().getSourceRange();
3693 TTP->removeDefaultArgument();
3697 } else if (TemplateParams) {
3698 if (TUK == TUK_Friend)
3699 Diag(KWLoc, diag::err_template_spec_friend)
3700 << FixItHint::CreateRemoval(
3701 SourceRange(TemplateParams->getTemplateLoc(),
3702 TemplateParams->getRAngleLoc()))
3703 << SourceRange(LAngleLoc, RAngleLoc);
3705 isExplicitSpecialization = true;
3706 } else if (TUK != TUK_Friend) {
3707 Diag(KWLoc, diag::err_template_spec_needs_header)
3708 << FixItHint::CreateInsertion(KWLoc, "template<> ");
3709 isExplicitSpecialization = true;
3712 // Check that the specialization uses the same tag kind as the
3713 // original template.
3714 TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec);
3715 assert(Kind != TTK_Enum && "Invalid enum tag in class template spec!");
3716 if (!isAcceptableTagRedeclaration(ClassTemplate->getTemplatedDecl(),
3718 *ClassTemplate->getIdentifier())) {
3719 Diag(KWLoc, diag::err_use_with_wrong_tag)
3721 << FixItHint::CreateReplacement(KWLoc,
3722 ClassTemplate->getTemplatedDecl()->getKindName());
3723 Diag(ClassTemplate->getTemplatedDecl()->getLocation(),
3724 diag::note_previous_use);
3725 Kind = ClassTemplate->getTemplatedDecl()->getTagKind();
3728 // Translate the parser's template argument list in our AST format.
3729 TemplateArgumentListInfo TemplateArgs;
3730 TemplateArgs.setLAngleLoc(LAngleLoc);
3731 TemplateArgs.setRAngleLoc(RAngleLoc);
3732 translateTemplateArguments(TemplateArgsIn, TemplateArgs);
3734 // Check that the template argument list is well-formed for this
3736 TemplateArgumentListBuilder Converted(ClassTemplate->getTemplateParameters(),
3737 TemplateArgs.size());
3738 if (CheckTemplateArgumentList(ClassTemplate, TemplateNameLoc,
3739 TemplateArgs, false, Converted))
3742 assert((Converted.structuredSize() ==
3743 ClassTemplate->getTemplateParameters()->size()) &&
3744 "Converted template argument list is too short!");
3746 // Find the class template (partial) specialization declaration that
3747 // corresponds to these arguments.
3748 if (isPartialSpecialization) {
3749 bool MirrorsPrimaryTemplate;
3750 if (CheckClassTemplatePartialSpecializationArgs(
3751 ClassTemplate->getTemplateParameters(),
3752 Converted, MirrorsPrimaryTemplate))
3755 if (MirrorsPrimaryTemplate) {
3756 // C++ [temp.class.spec]p9b3:
3758 // -- The argument list of the specialization shall not be identical
3759 // to the implicit argument list of the primary template.
3760 Diag(TemplateNameLoc, diag::err_partial_spec_args_match_primary_template)
3761 << (TUK == TUK_Definition)
3762 << FixItHint::CreateRemoval(SourceRange(LAngleLoc, RAngleLoc));
3763 return CheckClassTemplate(S, TagSpec, TUK, KWLoc, SS,
3764 ClassTemplate->getIdentifier(),
3771 // FIXME: Diagnose friend partial specializations
3773 if (!Name.isDependent() &&
3774 !TemplateSpecializationType::anyDependentTemplateArguments(
3775 TemplateArgs.getArgumentArray(),
3776 TemplateArgs.size())) {
3777 Diag(TemplateNameLoc, diag::err_partial_spec_fully_specialized)
3778 << ClassTemplate->getDeclName();
3779 isPartialSpecialization = false;
3783 void *InsertPos = 0;
3784 ClassTemplateSpecializationDecl *PrevDecl = 0;
3786 if (isPartialSpecialization)
3787 // FIXME: Template parameter list matters, too
3789 = ClassTemplate->findPartialSpecialization(Converted.getFlatArguments(),
3790 Converted.flatSize(),
3794 = ClassTemplate->findSpecialization(Converted.getFlatArguments(),
3795 Converted.flatSize(), InsertPos);
3797 ClassTemplateSpecializationDecl *Specialization = 0;
3799 // Check whether we can declare a class template specialization in
3800 // the current scope.
3801 if (TUK != TUK_Friend &&
3802 CheckTemplateSpecializationScope(*this, ClassTemplate, PrevDecl,
3804 isPartialSpecialization))
3807 // The canonical type
3810 (PrevDecl->getSpecializationKind() == TSK_Undeclared ||
3811 TUK == TUK_Friend)) {
3812 // Since the only prior class template specialization with these
3813 // arguments was referenced but not declared, or we're only
3814 // referencing this specialization as a friend, reuse that
3815 // declaration node as our own, updating its source location to
3816 // reflect our new declaration.
3817 Specialization = PrevDecl;
3818 Specialization->setLocation(TemplateNameLoc);
3820 CanonType = Context.getTypeDeclType(Specialization);
3821 } else if (isPartialSpecialization) {
3822 // Build the canonical type that describes the converted template
3823 // arguments of the class template partial specialization.
3824 TemplateName CanonTemplate = Context.getCanonicalTemplateName(Name);
3825 CanonType = Context.getTemplateSpecializationType(CanonTemplate,
3826 Converted.getFlatArguments(),
3827 Converted.flatSize());
3829 // Create a new class template partial specialization declaration node.
3830 ClassTemplatePartialSpecializationDecl *PrevPartial
3831 = cast_or_null<ClassTemplatePartialSpecializationDecl>(PrevDecl);
3832 unsigned SequenceNumber = PrevPartial? PrevPartial->getSequenceNumber()
3833 : ClassTemplate->getNextPartialSpecSequenceNumber();
3834 ClassTemplatePartialSpecializationDecl *Partial
3835 = ClassTemplatePartialSpecializationDecl::Create(Context, Kind,
3836 ClassTemplate->getDeclContext(),
3845 SetNestedNameSpecifier(Partial, SS);
3846 if (NumMatchedTemplateParamLists > 0 && SS.isSet()) {
3847 Partial->setTemplateParameterListsInfo(Context,
3848 NumMatchedTemplateParamLists,
3849 (TemplateParameterList**) TemplateParameterLists.release());
3853 ClassTemplate->AddPartialSpecialization(Partial, InsertPos);
3854 Specialization = Partial;
3856 // If we are providing an explicit specialization of a member class
3857 // template specialization, make a note of that.
3858 if (PrevPartial && PrevPartial->getInstantiatedFromMember())
3859 PrevPartial->setMemberSpecialization();
3861 // Check that all of the template parameters of the class template
3862 // partial specialization are deducible from the template
3863 // arguments. If not, this class template partial specialization
3864 // will never be used.
3865 llvm::SmallVector<bool, 8> DeducibleParams;
3866 DeducibleParams.resize(TemplateParams->size());
3867 MarkUsedTemplateParameters(Partial->getTemplateArgs(), true,
3868 TemplateParams->getDepth(),
3870 unsigned NumNonDeducible = 0;
3871 for (unsigned I = 0, N = DeducibleParams.size(); I != N; ++I)
3872 if (!DeducibleParams[I])
3875 if (NumNonDeducible) {
3876 Diag(TemplateNameLoc, diag::warn_partial_specs_not_deducible)
3877 << (NumNonDeducible > 1)
3878 << SourceRange(TemplateNameLoc, RAngleLoc);
3879 for (unsigned I = 0, N = DeducibleParams.size(); I != N; ++I) {
3880 if (!DeducibleParams[I]) {
3881 NamedDecl *Param = cast<NamedDecl>(TemplateParams->getParam(I));
3882 if (Param->getDeclName())
3883 Diag(Param->getLocation(),
3884 diag::note_partial_spec_unused_parameter)
3885 << Param->getDeclName();
3887 Diag(Param->getLocation(),
3888 diag::note_partial_spec_unused_parameter)
3894 // Create a new class template specialization declaration node for
3895 // this explicit specialization or friend declaration.
3897 = ClassTemplateSpecializationDecl::Create(Context, Kind,
3898 ClassTemplate->getDeclContext(),
3903 SetNestedNameSpecifier(Specialization, SS);
3904 if (NumMatchedTemplateParamLists > 0 && SS.isSet()) {
3905 Specialization->setTemplateParameterListsInfo(Context,
3906 NumMatchedTemplateParamLists,
3907 (TemplateParameterList**) TemplateParameterLists.release());
3911 ClassTemplate->AddSpecialization(Specialization, InsertPos);
3913 CanonType = Context.getTypeDeclType(Specialization);
3916 // C++ [temp.expl.spec]p6:
3917 // If a template, a member template or the member of a class template is
3918 // explicitly specialized then that specialization shall be declared
3919 // before the first use of that specialization that would cause an implicit
3920 // instantiation to take place, in every translation unit in which such a
3921 // use occurs; no diagnostic is required.
3922 if (PrevDecl && PrevDecl->getPointOfInstantiation().isValid()) {
3924 for (NamedDecl *Prev = PrevDecl; Prev; Prev = getPreviousDecl(Prev)) {
3925 // Is there any previous explicit specialization declaration?
3926 if (getTemplateSpecializationKind(Prev) == TSK_ExplicitSpecialization) {
3933 SourceRange Range(TemplateNameLoc, RAngleLoc);
3934 Diag(TemplateNameLoc, diag::err_specialization_after_instantiation)
3935 << Context.getTypeDeclType(Specialization) << Range;
3937 Diag(PrevDecl->getPointOfInstantiation(),
3938 diag::note_instantiation_required_here)
3939 << (PrevDecl->getTemplateSpecializationKind()
3940 != TSK_ImplicitInstantiation);
3945 // If this is not a friend, note that this is an explicit specialization.
3946 if (TUK != TUK_Friend)
3947 Specialization->setSpecializationKind(TSK_ExplicitSpecialization);
3949 // Check that this isn't a redefinition of this specialization.
3950 if (TUK == TUK_Definition) {
3951 if (RecordDecl *Def = Specialization->getDefinition()) {
3952 SourceRange Range(TemplateNameLoc, RAngleLoc);
3953 Diag(TemplateNameLoc, diag::err_redefinition)
3954 << Context.getTypeDeclType(Specialization) << Range;
3955 Diag(Def->getLocation(), diag::note_previous_definition);
3956 Specialization->setInvalidDecl();
3961 // Build the fully-sugared type for this class template
3962 // specialization as the user wrote in the specialization
3963 // itself. This means that we'll pretty-print the type retrieved
3964 // from the specialization's declaration the way that the user
3965 // actually wrote the specialization, rather than formatting the
3966 // name based on the "canonical" representation used to store the
3967 // template arguments in the specialization.
3968 TypeSourceInfo *WrittenTy
3969 = Context.getTemplateSpecializationTypeInfo(Name, TemplateNameLoc,
3970 TemplateArgs, CanonType);
3971 if (TUK != TUK_Friend) {
3972 Specialization->setTypeAsWritten(WrittenTy);
3974 Specialization->setTemplateKeywordLoc(TemplateParams->getTemplateLoc());
3976 TemplateArgsIn.release();
3978 // C++ [temp.expl.spec]p9:
3979 // A template explicit specialization is in the scope of the
3980 // namespace in which the template was defined.
3982 // We actually implement this paragraph where we set the semantic
3983 // context (in the creation of the ClassTemplateSpecializationDecl),
3984 // but we also maintain the lexical context where the actual
3985 // definition occurs.
3986 Specialization->setLexicalDeclContext(CurContext);
3988 // We may be starting the definition of this specialization.
3989 if (TUK == TUK_Definition)
3990 Specialization->startDefinition();
3992 if (TUK == TUK_Friend) {
3993 FriendDecl *Friend = FriendDecl::Create(Context, CurContext,
3997 Friend->setAccess(AS_public);
3998 CurContext->addDecl(Friend);
4000 // Add the specialization into its lexical context, so that it can
4001 // be seen when iterating through the list of declarations in that
4002 // context. However, specializations are not found by name lookup.
4003 CurContext->addDecl(Specialization);
4005 return Specialization;
4008 Decl *Sema::ActOnTemplateDeclarator(Scope *S,
4009 MultiTemplateParamsArg TemplateParameterLists,
4011 return HandleDeclarator(S, D, move(TemplateParameterLists), false);
4014 Decl *Sema::ActOnStartOfFunctionTemplateDef(Scope *FnBodyScope,
4015 MultiTemplateParamsArg TemplateParameterLists,
4017 assert(getCurFunctionDecl() == 0 && "Function parsing confused");
4018 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function &&
4019 "Not a function declarator!");
4020 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun;
4022 if (FTI.hasPrototype) {
4023 // FIXME: Diagnose arguments without names in C.
4026 Scope *ParentScope = FnBodyScope->getParent();
4028 Decl *DP = HandleDeclarator(ParentScope, D,
4029 move(TemplateParameterLists),
4030 /*IsFunctionDefinition=*/true);
4031 if (FunctionTemplateDecl *FunctionTemplate
4032 = dyn_cast_or_null<FunctionTemplateDecl>(DP))
4033 return ActOnStartOfFunctionDef(FnBodyScope,
4034 FunctionTemplate->getTemplatedDecl());
4035 if (FunctionDecl *Function = dyn_cast_or_null<FunctionDecl>(DP))
4036 return ActOnStartOfFunctionDef(FnBodyScope, Function);
4040 /// \brief Strips various properties off an implicit instantiation
4041 /// that has just been explicitly specialized.
4042 static void StripImplicitInstantiation(NamedDecl *D) {
4045 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
4046 FD->setInlineSpecified(false);
4050 /// \brief Diagnose cases where we have an explicit template specialization
4051 /// before/after an explicit template instantiation, producing diagnostics
4052 /// for those cases where they are required and determining whether the
4053 /// new specialization/instantiation will have any effect.
4055 /// \param NewLoc the location of the new explicit specialization or
4058 /// \param NewTSK the kind of the new explicit specialization or instantiation.
4060 /// \param PrevDecl the previous declaration of the entity.
4062 /// \param PrevTSK the kind of the old explicit specialization or instantiatin.
4064 /// \param PrevPointOfInstantiation if valid, indicates where the previus
4065 /// declaration was instantiated (either implicitly or explicitly).
4067 /// \param HasNoEffect will be set to true to indicate that the new
4068 /// specialization or instantiation has no effect and should be ignored.
4070 /// \returns true if there was an error that should prevent the introduction of
4071 /// the new declaration into the AST, false otherwise.
4073 Sema::CheckSpecializationInstantiationRedecl(SourceLocation NewLoc,
4074 TemplateSpecializationKind NewTSK,
4075 NamedDecl *PrevDecl,
4076 TemplateSpecializationKind PrevTSK,
4077 SourceLocation PrevPointOfInstantiation,
4078 bool &HasNoEffect) {
4079 HasNoEffect = false;
4082 case TSK_Undeclared:
4083 case TSK_ImplicitInstantiation:
4084 assert(false && "Don't check implicit instantiations here");
4087 case TSK_ExplicitSpecialization:
4089 case TSK_Undeclared:
4090 case TSK_ExplicitSpecialization:
4091 // Okay, we're just specializing something that is either already
4092 // explicitly specialized or has merely been mentioned without any
4096 case TSK_ImplicitInstantiation:
4097 if (PrevPointOfInstantiation.isInvalid()) {
4098 // The declaration itself has not actually been instantiated, so it is
4099 // still okay to specialize it.
4100 StripImplicitInstantiation(PrevDecl);
4105 case TSK_ExplicitInstantiationDeclaration:
4106 case TSK_ExplicitInstantiationDefinition:
4107 assert((PrevTSK == TSK_ImplicitInstantiation ||
4108 PrevPointOfInstantiation.isValid()) &&
4109 "Explicit instantiation without point of instantiation?");
4111 // C++ [temp.expl.spec]p6:
4112 // If a template, a member template or the member of a class template
4113 // is explicitly specialized then that specialization shall be declared
4114 // before the first use of that specialization that would cause an
4115 // implicit instantiation to take place, in every translation unit in
4116 // which such a use occurs; no diagnostic is required.
4117 for (NamedDecl *Prev = PrevDecl; Prev; Prev = getPreviousDecl(Prev)) {
4118 // Is there any previous explicit specialization declaration?
4119 if (getTemplateSpecializationKind(Prev) == TSK_ExplicitSpecialization)
4123 Diag(NewLoc, diag::err_specialization_after_instantiation)
4125 Diag(PrevPointOfInstantiation, diag::note_instantiation_required_here)
4126 << (PrevTSK != TSK_ImplicitInstantiation);
4132 case TSK_ExplicitInstantiationDeclaration:
4134 case TSK_ExplicitInstantiationDeclaration:
4135 // This explicit instantiation declaration is redundant (that's okay).
4139 case TSK_Undeclared:
4140 case TSK_ImplicitInstantiation:
4141 // We're explicitly instantiating something that may have already been
4142 // implicitly instantiated; that's fine.
4145 case TSK_ExplicitSpecialization:
4146 // C++0x [temp.explicit]p4:
4147 // For a given set of template parameters, if an explicit instantiation
4148 // of a template appears after a declaration of an explicit
4149 // specialization for that template, the explicit instantiation has no
4154 case TSK_ExplicitInstantiationDefinition:
4155 // C++0x [temp.explicit]p10:
4156 // If an entity is the subject of both an explicit instantiation
4157 // declaration and an explicit instantiation definition in the same
4158 // translation unit, the definition shall follow the declaration.
4160 diag::err_explicit_instantiation_declaration_after_definition);
4161 Diag(PrevPointOfInstantiation,
4162 diag::note_explicit_instantiation_definition_here);
4163 assert(PrevPointOfInstantiation.isValid() &&
4164 "Explicit instantiation without point of instantiation?");
4170 case TSK_ExplicitInstantiationDefinition:
4172 case TSK_Undeclared:
4173 case TSK_ImplicitInstantiation:
4174 // We're explicitly instantiating something that may have already been
4175 // implicitly instantiated; that's fine.
4178 case TSK_ExplicitSpecialization:
4179 // C++ DR 259, C++0x [temp.explicit]p4:
4180 // For a given set of template parameters, if an explicit
4181 // instantiation of a template appears after a declaration of
4182 // an explicit specialization for that template, the explicit
4183 // instantiation has no effect.
4185 // In C++98/03 mode, we only give an extension warning here, because it
4186 // is not harmful to try to explicitly instantiate something that
4187 // has been explicitly specialized.
4188 if (!getLangOptions().CPlusPlus0x) {
4189 Diag(NewLoc, diag::ext_explicit_instantiation_after_specialization)
4191 Diag(PrevDecl->getLocation(),
4192 diag::note_previous_template_specialization);
4197 case TSK_ExplicitInstantiationDeclaration:
4198 // We're explicity instantiating a definition for something for which we
4199 // were previously asked to suppress instantiations. That's fine.
4202 case TSK_ExplicitInstantiationDefinition:
4203 // C++0x [temp.spec]p5:
4204 // For a given template and a given set of template-arguments,
4205 // - an explicit instantiation definition shall appear at most once
4207 Diag(NewLoc, diag::err_explicit_instantiation_duplicate)
4209 Diag(PrevPointOfInstantiation,
4210 diag::note_previous_explicit_instantiation);
4217 assert(false && "Missing specialization/instantiation case?");
4222 /// \brief Perform semantic analysis for the given dependent function
4223 /// template specialization. The only possible way to get a dependent
4224 /// function template specialization is with a friend declaration,
4227 /// template <class T> void foo(T);
4228 /// template <class T> class A {
4229 /// friend void foo<>(T);
4232 /// There really isn't any useful analysis we can do here, so we
4233 /// just store the information.
4235 Sema::CheckDependentFunctionTemplateSpecialization(FunctionDecl *FD,
4236 const TemplateArgumentListInfo &ExplicitTemplateArgs,
4237 LookupResult &Previous) {
4238 // Remove anything from Previous that isn't a function template in
4239 // the correct context.
4240 DeclContext *FDLookupContext = FD->getDeclContext()->getRedeclContext();
4241 LookupResult::Filter F = Previous.makeFilter();
4242 while (F.hasNext()) {
4243 NamedDecl *D = F.next()->getUnderlyingDecl();
4244 if (!isa<FunctionTemplateDecl>(D) ||
4245 !FDLookupContext->InEnclosingNamespaceSetOf(
4246 D->getDeclContext()->getRedeclContext()))
4251 // Should this be diagnosed here?
4252 if (Previous.empty()) return true;
4254 FD->setDependentTemplateSpecialization(Context, Previous.asUnresolvedSet(),
4255 ExplicitTemplateArgs);
4259 /// \brief Perform semantic analysis for the given function template
4262 /// This routine performs all of the semantic analysis required for an
4263 /// explicit function template specialization. On successful completion,
4264 /// the function declaration \p FD will become a function template
4267 /// \param FD the function declaration, which will be updated to become a
4268 /// function template specialization.
4270 /// \param ExplicitTemplateArgs the explicitly-provided template arguments,
4271 /// if any. Note that this may be valid info even when 0 arguments are
4272 /// explicitly provided as in, e.g., \c void sort<>(char*, char*);
4273 /// as it anyway contains info on the angle brackets locations.
4275 /// \param PrevDecl the set of declarations that may be specialized by
4276 /// this function specialization.
4278 Sema::CheckFunctionTemplateSpecialization(FunctionDecl *FD,
4279 const TemplateArgumentListInfo *ExplicitTemplateArgs,
4280 LookupResult &Previous) {
4281 // The set of function template specializations that could match this
4282 // explicit function template specialization.
4283 UnresolvedSet<8> Candidates;
4285 DeclContext *FDLookupContext = FD->getDeclContext()->getRedeclContext();
4286 for (LookupResult::iterator I = Previous.begin(), E = Previous.end();
4288 NamedDecl *Ovl = (*I)->getUnderlyingDecl();
4289 if (FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(Ovl)) {
4290 // Only consider templates found within the same semantic lookup scope as
4292 if (!FDLookupContext->InEnclosingNamespaceSetOf(
4293 Ovl->getDeclContext()->getRedeclContext()))
4296 // C++ [temp.expl.spec]p11:
4297 // A trailing template-argument can be left unspecified in the
4298 // template-id naming an explicit function template specialization
4299 // provided it can be deduced from the function argument type.
4300 // Perform template argument deduction to determine whether we may be
4301 // specializing this template.
4302 // FIXME: It is somewhat wasteful to build
4303 TemplateDeductionInfo Info(Context, FD->getLocation());
4304 FunctionDecl *Specialization = 0;
4305 if (TemplateDeductionResult TDK
4306 = DeduceTemplateArguments(FunTmpl, ExplicitTemplateArgs,
4310 // FIXME: Template argument deduction failed; record why it failed, so
4311 // that we can provide nifty diagnostics.
4316 // Record this candidate.
4317 Candidates.addDecl(Specialization, I.getAccess());
4321 // Find the most specialized function template.
4322 UnresolvedSetIterator Result
4323 = getMostSpecialized(Candidates.begin(), Candidates.end(),
4324 TPOC_Other, FD->getLocation(),
4325 PDiag(diag::err_function_template_spec_no_match)
4326 << FD->getDeclName(),
4327 PDiag(diag::err_function_template_spec_ambiguous)
4328 << FD->getDeclName() << (ExplicitTemplateArgs != 0),
4329 PDiag(diag::note_function_template_spec_matched));
4330 if (Result == Candidates.end())
4333 // Ignore access information; it doesn't figure into redeclaration checking.
4334 FunctionDecl *Specialization = cast<FunctionDecl>(*Result);
4335 Specialization->setLocation(FD->getLocation());
4337 // FIXME: Check if the prior specialization has a point of instantiation.
4338 // If so, we have run afoul of .
4340 // If this is a friend declaration, then we're not really declaring
4341 // an explicit specialization.
4342 bool isFriend = (FD->getFriendObjectKind() != Decl::FOK_None);
4344 // Check the scope of this explicit specialization.
4346 CheckTemplateSpecializationScope(*this,
4347 Specialization->getPrimaryTemplate(),
4348 Specialization, FD->getLocation(),
4352 // C++ [temp.expl.spec]p6:
4353 // If a template, a member template or the member of a class template is
4354 // explicitly specialized then that specialization shall be declared
4355 // before the first use of that specialization that would cause an implicit
4356 // instantiation to take place, in every translation unit in which such a
4357 // use occurs; no diagnostic is required.
4358 FunctionTemplateSpecializationInfo *SpecInfo
4359 = Specialization->getTemplateSpecializationInfo();
4360 assert(SpecInfo && "Function template specialization info missing?");
4362 bool HasNoEffect = false;
4364 CheckSpecializationInstantiationRedecl(FD->getLocation(),
4365 TSK_ExplicitSpecialization,
4367 SpecInfo->getTemplateSpecializationKind(),
4368 SpecInfo->getPointOfInstantiation(),
4372 // Mark the prior declaration as an explicit specialization, so that later
4373 // clients know that this is an explicit specialization.
4375 SpecInfo->setTemplateSpecializationKind(TSK_ExplicitSpecialization);
4376 MarkUnusedFileScopedDecl(Specialization);
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 MarkUnusedFileScopedDecl(InstantiationFunction);
4531 } else if (isa<VarDecl>(Member)) {
4532 VarDecl *InstantiationVar = cast<VarDecl>(Instantiation);
4533 if (InstantiationVar->getTemplateSpecializationKind() ==
4534 TSK_ImplicitInstantiation) {
4535 InstantiationVar->setTemplateSpecializationKind(
4536 TSK_ExplicitSpecialization);
4537 InstantiationVar->setLocation(Member->getLocation());
4540 Context.setInstantiatedFromStaticDataMember(cast<VarDecl>(Member),
4541 cast<VarDecl>(InstantiatedFrom),
4542 TSK_ExplicitSpecialization);
4543 MarkUnusedFileScopedDecl(InstantiationVar);
4545 assert(isa<CXXRecordDecl>(Member) && "Only member classes remain");
4546 CXXRecordDecl *InstantiationClass = cast<CXXRecordDecl>(Instantiation);
4547 if (InstantiationClass->getTemplateSpecializationKind() ==
4548 TSK_ImplicitInstantiation) {
4549 InstantiationClass->setTemplateSpecializationKind(
4550 TSK_ExplicitSpecialization);
4551 InstantiationClass->setLocation(Member->getLocation());
4554 cast<CXXRecordDecl>(Member)->setInstantiationOfMemberClass(
4555 cast<CXXRecordDecl>(InstantiatedFrom),
4556 TSK_ExplicitSpecialization);
4559 // Save the caller the trouble of having to figure out which declaration
4560 // this specialization matches.
4562 Previous.addDecl(Instantiation);
4566 /// \brief Check the scope of an explicit instantiation.
4568 /// \returns true if a serious error occurs, false otherwise.
4569 static bool CheckExplicitInstantiationScope(Sema &S, NamedDecl *D,
4570 SourceLocation InstLoc,
4571 bool WasQualifiedName) {
4572 DeclContext *OrigContext= D->getDeclContext()->getEnclosingNamespaceContext();
4573 DeclContext *CurContext = S.CurContext->getRedeclContext();
4575 if (CurContext->isRecord()) {
4576 S.Diag(InstLoc, diag::err_explicit_instantiation_in_class)
4581 // C++0x [temp.explicit]p2:
4582 // An explicit instantiation shall appear in an enclosing namespace of its
4585 // This is DR275, which we do not retroactively apply to C++98/03.
4586 if (S.getLangOptions().CPlusPlus0x &&
4587 !CurContext->Encloses(OrigContext)) {
4588 if (NamespaceDecl *NS = dyn_cast<NamespaceDecl>(OrigContext))
4590 S.getLangOptions().CPlusPlus0x?
4591 diag::err_explicit_instantiation_out_of_scope
4592 : diag::warn_explicit_instantiation_out_of_scope_0x)
4596 S.getLangOptions().CPlusPlus0x?
4597 diag::err_explicit_instantiation_must_be_global
4598 : diag::warn_explicit_instantiation_out_of_scope_0x)
4600 S.Diag(D->getLocation(), diag::note_explicit_instantiation_here);
4604 // C++0x [temp.explicit]p2:
4605 // If the name declared in the explicit instantiation is an unqualified
4606 // name, the explicit instantiation shall appear in the namespace where
4607 // its template is declared or, if that namespace is inline (7.3.1), any
4608 // namespace from its enclosing namespace set.
4609 if (WasQualifiedName)
4612 if (CurContext->InEnclosingNamespaceSetOf(OrigContext))
4616 S.getLangOptions().CPlusPlus0x?
4617 diag::err_explicit_instantiation_unqualified_wrong_namespace
4618 : diag::warn_explicit_instantiation_unqualified_wrong_namespace_0x)
4619 << D << OrigContext;
4620 S.Diag(D->getLocation(), diag::note_explicit_instantiation_here);
4624 /// \brief Determine whether the given scope specifier has a template-id in it.
4625 static bool ScopeSpecifierHasTemplateId(const CXXScopeSpec &SS) {
4629 // C++0x [temp.explicit]p2:
4630 // If the explicit instantiation is for a member function, a member class
4631 // or a static data member of a class template specialization, the name of
4632 // the class template specialization in the qualified-id for the member
4633 // name shall be a simple-template-id.
4635 // C++98 has the same restriction, just worded differently.
4636 for (NestedNameSpecifier *NNS = (NestedNameSpecifier *)SS.getScopeRep();
4637 NNS; NNS = NNS->getPrefix())
4638 if (Type *T = NNS->getAsType())
4639 if (isa<TemplateSpecializationType>(T))
4645 // Explicit instantiation of a class template specialization
4647 Sema::ActOnExplicitInstantiation(Scope *S,
4648 SourceLocation ExternLoc,
4649 SourceLocation TemplateLoc,
4651 SourceLocation KWLoc,
4652 const CXXScopeSpec &SS,
4653 TemplateTy TemplateD,
4654 SourceLocation TemplateNameLoc,
4655 SourceLocation LAngleLoc,
4656 ASTTemplateArgsPtr TemplateArgsIn,
4657 SourceLocation RAngleLoc,
4658 AttributeList *Attr) {
4659 // Find the class template we're specializing
4660 TemplateName Name = TemplateD.getAsVal<TemplateName>();
4661 ClassTemplateDecl *ClassTemplate
4662 = cast<ClassTemplateDecl>(Name.getAsTemplateDecl());
4664 // Check that the specialization uses the same tag kind as the
4665 // original template.
4666 TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec);
4667 assert(Kind != TTK_Enum &&
4668 "Invalid enum tag in class template explicit instantiation!");
4669 if (!isAcceptableTagRedeclaration(ClassTemplate->getTemplatedDecl(),
4671 *ClassTemplate->getIdentifier())) {
4672 Diag(KWLoc, diag::err_use_with_wrong_tag)
4674 << FixItHint::CreateReplacement(KWLoc,
4675 ClassTemplate->getTemplatedDecl()->getKindName());
4676 Diag(ClassTemplate->getTemplatedDecl()->getLocation(),
4677 diag::note_previous_use);
4678 Kind = ClassTemplate->getTemplatedDecl()->getTagKind();
4681 // C++0x [temp.explicit]p2:
4682 // There are two forms of explicit instantiation: an explicit instantiation
4683 // definition and an explicit instantiation declaration. An explicit
4684 // instantiation declaration begins with the extern keyword. [...]
4685 TemplateSpecializationKind TSK
4686 = ExternLoc.isInvalid()? TSK_ExplicitInstantiationDefinition
4687 : TSK_ExplicitInstantiationDeclaration;
4689 // Translate the parser's template argument list in our AST format.
4690 TemplateArgumentListInfo TemplateArgs(LAngleLoc, RAngleLoc);
4691 translateTemplateArguments(TemplateArgsIn, TemplateArgs);
4693 // Check that the template argument list is well-formed for this
4695 TemplateArgumentListBuilder Converted(ClassTemplate->getTemplateParameters(),
4696 TemplateArgs.size());
4697 if (CheckTemplateArgumentList(ClassTemplate, TemplateNameLoc,
4698 TemplateArgs, false, Converted))
4701 assert((Converted.structuredSize() ==
4702 ClassTemplate->getTemplateParameters()->size()) &&
4703 "Converted template argument list is too short!");
4705 // Find the class template specialization declaration that
4706 // corresponds to these arguments.
4707 void *InsertPos = 0;
4708 ClassTemplateSpecializationDecl *PrevDecl
4709 = ClassTemplate->findSpecialization(Converted.getFlatArguments(),
4710 Converted.flatSize(), InsertPos);
4712 TemplateSpecializationKind PrevDecl_TSK
4713 = PrevDecl ? PrevDecl->getTemplateSpecializationKind() : TSK_Undeclared;
4715 // C++0x [temp.explicit]p2:
4716 // [...] An explicit instantiation shall appear in an enclosing
4717 // namespace of its template. [...]
4719 // This is C++ DR 275.
4720 if (CheckExplicitInstantiationScope(*this, ClassTemplate, TemplateNameLoc,
4724 ClassTemplateSpecializationDecl *Specialization = 0;
4726 bool ReusedDecl = false;
4727 bool HasNoEffect = false;
4729 if (CheckSpecializationInstantiationRedecl(TemplateNameLoc, TSK,
4730 PrevDecl, PrevDecl_TSK,
4731 PrevDecl->getPointOfInstantiation(),
4735 // Even though HasNoEffect == true means that this explicit instantiation
4736 // has no effect on semantics, we go on to put its syntax in the AST.
4738 if (PrevDecl_TSK == TSK_ImplicitInstantiation ||
4739 PrevDecl_TSK == TSK_Undeclared) {
4740 // Since the only prior class template specialization with these
4741 // arguments was referenced but not declared, reuse that
4742 // declaration node as our own, updating the source location
4743 // for the template name to reflect our new declaration.
4744 // (Other source locations will be updated later.)
4745 Specialization = PrevDecl;
4746 Specialization->setLocation(TemplateNameLoc);
4752 if (!Specialization) {
4753 // Create a new class template specialization declaration node for
4754 // this explicit specialization.
4756 = ClassTemplateSpecializationDecl::Create(Context, Kind,
4757 ClassTemplate->getDeclContext(),
4760 Converted, PrevDecl);
4761 SetNestedNameSpecifier(Specialization, SS);
4763 if (!HasNoEffect && !PrevDecl) {
4764 // Insert the new specialization.
4765 ClassTemplate->AddSpecialization(Specialization, InsertPos);
4769 // Build the fully-sugared type for this explicit instantiation as
4770 // the user wrote in the explicit instantiation itself. This means
4771 // that we'll pretty-print the type retrieved from the
4772 // specialization's declaration the way that the user actually wrote
4773 // the explicit instantiation, rather than formatting the name based
4774 // on the "canonical" representation used to store the template
4775 // arguments in the specialization.
4776 TypeSourceInfo *WrittenTy
4777 = Context.getTemplateSpecializationTypeInfo(Name, TemplateNameLoc,
4779 Context.getTypeDeclType(Specialization));
4780 Specialization->setTypeAsWritten(WrittenTy);
4781 TemplateArgsIn.release();
4783 // Set source locations for keywords.
4784 Specialization->setExternLoc(ExternLoc);
4785 Specialization->setTemplateKeywordLoc(TemplateLoc);
4787 // Add the explicit instantiation into its lexical context. However,
4788 // since explicit instantiations are never found by name lookup, we
4789 // just put it into the declaration context directly.
4790 Specialization->setLexicalDeclContext(CurContext);
4791 CurContext->addDecl(Specialization);
4793 // Syntax is now OK, so return if it has no other effect on semantics.
4795 // Set the template specialization kind.
4796 Specialization->setTemplateSpecializationKind(TSK);
4797 return Specialization;
4800 // C++ [temp.explicit]p3:
4801 // A definition of a class template or class member template
4802 // shall be in scope at the point of the explicit instantiation of
4803 // the class template or class member template.
4805 // This check comes when we actually try to perform the
4807 ClassTemplateSpecializationDecl *Def
4808 = cast_or_null<ClassTemplateSpecializationDecl>(
4809 Specialization->getDefinition());
4811 InstantiateClassTemplateSpecialization(TemplateNameLoc, Specialization, TSK);
4812 else if (TSK == TSK_ExplicitInstantiationDefinition) {
4813 MarkVTableUsed(TemplateNameLoc, Specialization, true);
4814 Specialization->setPointOfInstantiation(Def->getPointOfInstantiation());
4817 // Instantiate the members of this class template specialization.
4818 Def = cast_or_null<ClassTemplateSpecializationDecl>(
4819 Specialization->getDefinition());
4821 TemplateSpecializationKind Old_TSK = Def->getTemplateSpecializationKind();
4823 // Fix a TSK_ExplicitInstantiationDeclaration followed by a
4824 // TSK_ExplicitInstantiationDefinition
4825 if (Old_TSK == TSK_ExplicitInstantiationDeclaration &&
4826 TSK == TSK_ExplicitInstantiationDefinition)
4827 Def->setTemplateSpecializationKind(TSK);
4829 InstantiateClassTemplateSpecializationMembers(TemplateNameLoc, Def, TSK);
4832 // Set the template specialization kind.
4833 Specialization->setTemplateSpecializationKind(TSK);
4834 return Specialization;
4837 // Explicit instantiation of a member class of a class template.
4839 Sema::ActOnExplicitInstantiation(Scope *S,
4840 SourceLocation ExternLoc,
4841 SourceLocation TemplateLoc,
4843 SourceLocation KWLoc,
4845 IdentifierInfo *Name,
4846 SourceLocation NameLoc,
4847 AttributeList *Attr) {
4850 bool IsDependent = false;
4851 Decl *TagD = ActOnTag(S, TagSpec, Sema::TUK_Reference,
4852 KWLoc, SS, Name, NameLoc, Attr, AS_none,
4853 MultiTemplateParamsArg(*this, 0, 0),
4854 Owned, IsDependent);
4855 assert(!IsDependent && "explicit instantiation of dependent name not yet handled");
4860 TagDecl *Tag = cast<TagDecl>(TagD);
4861 if (Tag->isEnum()) {
4862 Diag(TemplateLoc, diag::err_explicit_instantiation_enum)
4863 << Context.getTypeDeclType(Tag);
4867 if (Tag->isInvalidDecl())
4870 CXXRecordDecl *Record = cast<CXXRecordDecl>(Tag);
4871 CXXRecordDecl *Pattern = Record->getInstantiatedFromMemberClass();
4873 Diag(TemplateLoc, diag::err_explicit_instantiation_nontemplate_type)
4874 << Context.getTypeDeclType(Record);
4875 Diag(Record->getLocation(), diag::note_nontemplate_decl_here);
4879 // C++0x [temp.explicit]p2:
4880 // If the explicit instantiation is for a class or member class, the
4881 // elaborated-type-specifier in the declaration shall include a
4882 // simple-template-id.
4884 // C++98 has the same restriction, just worded differently.
4885 if (!ScopeSpecifierHasTemplateId(SS))
4886 Diag(TemplateLoc, diag::ext_explicit_instantiation_without_qualified_id)
4887 << Record << SS.getRange();
4889 // C++0x [temp.explicit]p2:
4890 // There are two forms of explicit instantiation: an explicit instantiation
4891 // definition and an explicit instantiation declaration. An explicit
4892 // instantiation declaration begins with the extern keyword. [...]
4893 TemplateSpecializationKind TSK
4894 = ExternLoc.isInvalid()? TSK_ExplicitInstantiationDefinition
4895 : TSK_ExplicitInstantiationDeclaration;
4897 // C++0x [temp.explicit]p2:
4898 // [...] An explicit instantiation shall appear in an enclosing
4899 // namespace of its template. [...]
4901 // This is C++ DR 275.
4902 CheckExplicitInstantiationScope(*this, Record, NameLoc, true);
4904 // Verify that it is okay to explicitly instantiate here.
4905 CXXRecordDecl *PrevDecl
4906 = cast_or_null<CXXRecordDecl>(Record->getPreviousDeclaration());
4907 if (!PrevDecl && Record->getDefinition())
4910 MemberSpecializationInfo *MSInfo = PrevDecl->getMemberSpecializationInfo();
4911 bool HasNoEffect = false;
4912 assert(MSInfo && "No member specialization information?");
4913 if (CheckSpecializationInstantiationRedecl(TemplateLoc, TSK,
4915 MSInfo->getTemplateSpecializationKind(),
4916 MSInfo->getPointOfInstantiation(),
4923 CXXRecordDecl *RecordDef
4924 = cast_or_null<CXXRecordDecl>(Record->getDefinition());
4926 // C++ [temp.explicit]p3:
4927 // A definition of a member class of a class template shall be in scope
4928 // at the point of an explicit instantiation of the member class.
4930 = cast_or_null<CXXRecordDecl>(Pattern->getDefinition());
4932 Diag(TemplateLoc, diag::err_explicit_instantiation_undefined_member)
4933 << 0 << Record->getDeclName() << Record->getDeclContext();
4934 Diag(Pattern->getLocation(), diag::note_forward_declaration)
4938 if (InstantiateClass(NameLoc, Record, Def,
4939 getTemplateInstantiationArgs(Record),
4943 RecordDef = cast_or_null<CXXRecordDecl>(Record->getDefinition());
4949 // Instantiate all of the members of the class.
4950 InstantiateClassMembers(NameLoc, RecordDef,
4951 getTemplateInstantiationArgs(Record), TSK);
4953 if (TSK == TSK_ExplicitInstantiationDefinition)
4954 MarkVTableUsed(NameLoc, RecordDef, true);
4956 // FIXME: We don't have any representation for explicit instantiations of
4957 // member classes. Such a representation is not needed for compilation, but it
4958 // should be available for clients that want to see all of the declarations in
4963 DeclResult Sema::ActOnExplicitInstantiation(Scope *S,
4964 SourceLocation ExternLoc,
4965 SourceLocation TemplateLoc,
4967 // Explicit instantiations always require a name.
4968 // TODO: check if/when DNInfo should replace Name.
4969 DeclarationNameInfo NameInfo = GetNameForDeclarator(D);
4970 DeclarationName Name = NameInfo.getName();
4972 if (!D.isInvalidType())
4973 Diag(D.getDeclSpec().getSourceRange().getBegin(),
4974 diag::err_explicit_instantiation_requires_name)
4975 << D.getDeclSpec().getSourceRange()
4976 << D.getSourceRange();
4981 // The scope passed in may not be a decl scope. Zip up the scope tree until
4982 // we find one that is.
4983 while ((S->getFlags() & Scope::DeclScope) == 0 ||
4984 (S->getFlags() & Scope::TemplateParamScope) != 0)
4987 // Determine the type of the declaration.
4988 TypeSourceInfo *T = GetTypeForDeclarator(D, S);
4989 QualType R = T->getType();
4993 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) {
4994 // Cannot explicitly instantiate a typedef.
4995 Diag(D.getIdentifierLoc(), diag::err_explicit_instantiation_of_typedef)
5000 // C++0x [temp.explicit]p1:
5001 // [...] An explicit instantiation of a function template shall not use the
5002 // inline or constexpr specifiers.
5003 // Presumably, this also applies to member functions of class templates as
5005 if (D.getDeclSpec().isInlineSpecified() && getLangOptions().CPlusPlus0x)
5006 Diag(D.getDeclSpec().getInlineSpecLoc(),
5007 diag::err_explicit_instantiation_inline)
5008 <<FixItHint::CreateRemoval(D.getDeclSpec().getInlineSpecLoc());
5010 // FIXME: check for constexpr specifier.
5012 // C++0x [temp.explicit]p2:
5013 // There are two forms of explicit instantiation: an explicit instantiation
5014 // definition and an explicit instantiation declaration. An explicit
5015 // instantiation declaration begins with the extern keyword. [...]
5016 TemplateSpecializationKind TSK
5017 = ExternLoc.isInvalid()? TSK_ExplicitInstantiationDefinition
5018 : TSK_ExplicitInstantiationDeclaration;
5020 LookupResult Previous(*this, NameInfo, LookupOrdinaryName);
5021 LookupParsedName(Previous, S, &D.getCXXScopeSpec());
5023 if (!R->isFunctionType()) {
5024 // C++ [temp.explicit]p1:
5025 // A [...] static data member of a class template can be explicitly
5026 // instantiated from the member definition associated with its class
5028 if (Previous.isAmbiguous())
5031 VarDecl *Prev = Previous.getAsSingle<VarDecl>();
5032 if (!Prev || !Prev->isStaticDataMember()) {
5033 // We expect to see a data data member here.
5034 Diag(D.getIdentifierLoc(), diag::err_explicit_instantiation_not_known)
5036 for (LookupResult::iterator P = Previous.begin(), PEnd = Previous.end();
5038 Diag((*P)->getLocation(), diag::note_explicit_instantiation_here);
5042 if (!Prev->getInstantiatedFromStaticDataMember()) {
5043 // FIXME: Check for explicit specialization?
5044 Diag(D.getIdentifierLoc(),
5045 diag::err_explicit_instantiation_data_member_not_instantiated)
5047 Diag(Prev->getLocation(), diag::note_explicit_instantiation_here);
5048 // FIXME: Can we provide a note showing where this was declared?
5052 // C++0x [temp.explicit]p2:
5053 // If the explicit instantiation is for a member function, a member class
5054 // or a static data member of a class template specialization, the name of
5055 // the class template specialization in the qualified-id for the member
5056 // name shall be a simple-template-id.
5058 // C++98 has the same restriction, just worded differently.
5059 if (!ScopeSpecifierHasTemplateId(D.getCXXScopeSpec()))
5060 Diag(D.getIdentifierLoc(),
5061 diag::ext_explicit_instantiation_without_qualified_id)
5062 << Prev << D.getCXXScopeSpec().getRange();
5064 // Check the scope of this explicit instantiation.
5065 CheckExplicitInstantiationScope(*this, Prev, D.getIdentifierLoc(), true);
5067 // Verify that it is okay to explicitly instantiate here.
5068 MemberSpecializationInfo *MSInfo = Prev->getMemberSpecializationInfo();
5069 assert(MSInfo && "Missing static data member specialization info?");
5070 bool HasNoEffect = false;
5071 if (CheckSpecializationInstantiationRedecl(D.getIdentifierLoc(), TSK, Prev,
5072 MSInfo->getTemplateSpecializationKind(),
5073 MSInfo->getPointOfInstantiation(),
5079 // Instantiate static data member.
5080 Prev->setTemplateSpecializationKind(TSK, D.getIdentifierLoc());
5081 if (TSK == TSK_ExplicitInstantiationDefinition)
5082 InstantiateStaticDataMemberDefinition(D.getIdentifierLoc(), Prev);
5084 // FIXME: Create an ExplicitInstantiation node?
5088 // If the declarator is a template-id, translate the parser's template
5089 // argument list into our AST format.
5090 bool HasExplicitTemplateArgs = false;
5091 TemplateArgumentListInfo TemplateArgs;
5092 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) {
5093 TemplateIdAnnotation *TemplateId = D.getName().TemplateId;
5094 TemplateArgs.setLAngleLoc(TemplateId->LAngleLoc);
5095 TemplateArgs.setRAngleLoc(TemplateId->RAngleLoc);
5096 ASTTemplateArgsPtr TemplateArgsPtr(*this,
5097 TemplateId->getTemplateArgs(),
5098 TemplateId->NumArgs);
5099 translateTemplateArguments(TemplateArgsPtr, TemplateArgs);
5100 HasExplicitTemplateArgs = true;
5101 TemplateArgsPtr.release();
5104 // C++ [temp.explicit]p1:
5105 // A [...] function [...] can be explicitly instantiated from its template.
5106 // A member function [...] of a class template can be explicitly
5107 // instantiated from the member definition associated with its class
5109 UnresolvedSet<8> Matches;
5110 for (LookupResult::iterator P = Previous.begin(), PEnd = Previous.end();
5112 NamedDecl *Prev = *P;
5113 if (!HasExplicitTemplateArgs) {
5114 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Prev)) {
5115 if (Context.hasSameUnqualifiedType(Method->getType(), R)) {
5118 Matches.addDecl(Method, P.getAccess());
5119 if (Method->getTemplateSpecializationKind() == TSK_Undeclared)
5125 FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(Prev);
5129 TemplateDeductionInfo Info(Context, D.getIdentifierLoc());
5130 FunctionDecl *Specialization = 0;
5131 if (TemplateDeductionResult TDK
5132 = DeduceTemplateArguments(FunTmpl,
5133 (HasExplicitTemplateArgs ? &TemplateArgs : 0),
5134 R, Specialization, Info)) {
5135 // FIXME: Keep track of almost-matches?
5140 Matches.addDecl(Specialization, P.getAccess());
5143 // Find the most specialized function template specialization.
5144 UnresolvedSetIterator Result
5145 = getMostSpecialized(Matches.begin(), Matches.end(), TPOC_Other,
5146 D.getIdentifierLoc(),
5147 PDiag(diag::err_explicit_instantiation_not_known) << Name,
5148 PDiag(diag::err_explicit_instantiation_ambiguous) << Name,
5149 PDiag(diag::note_explicit_instantiation_candidate));
5151 if (Result == Matches.end())
5154 // Ignore access control bits, we don't need them for redeclaration checking.
5155 FunctionDecl *Specialization = cast<FunctionDecl>(*Result);
5157 if (Specialization->getTemplateSpecializationKind() == TSK_Undeclared) {
5158 Diag(D.getIdentifierLoc(),
5159 diag::err_explicit_instantiation_member_function_not_instantiated)
5161 << (Specialization->getTemplateSpecializationKind() ==
5162 TSK_ExplicitSpecialization);
5163 Diag(Specialization->getLocation(), diag::note_explicit_instantiation_here);
5167 FunctionDecl *PrevDecl = Specialization->getPreviousDeclaration();
5168 if (!PrevDecl && Specialization->isThisDeclarationADefinition())
5169 PrevDecl = Specialization;
5172 bool HasNoEffect = false;
5173 if (CheckSpecializationInstantiationRedecl(D.getIdentifierLoc(), TSK,
5175 PrevDecl->getTemplateSpecializationKind(),
5176 PrevDecl->getPointOfInstantiation(),
5180 // FIXME: We may still want to build some representation of this
5181 // explicit specialization.
5186 Specialization->setTemplateSpecializationKind(TSK, D.getIdentifierLoc());
5188 if (TSK == TSK_ExplicitInstantiationDefinition)
5189 InstantiateFunctionDefinition(D.getIdentifierLoc(), Specialization);
5191 // C++0x [temp.explicit]p2:
5192 // If the explicit instantiation is for a member function, a member class
5193 // or a static data member of a class template specialization, the name of
5194 // the class template specialization in the qualified-id for the member
5195 // name shall be a simple-template-id.
5197 // C++98 has the same restriction, just worded differently.
5198 FunctionTemplateDecl *FunTmpl = Specialization->getPrimaryTemplate();
5199 if (D.getName().getKind() != UnqualifiedId::IK_TemplateId && !FunTmpl &&
5200 D.getCXXScopeSpec().isSet() &&
5201 !ScopeSpecifierHasTemplateId(D.getCXXScopeSpec()))
5202 Diag(D.getIdentifierLoc(),
5203 diag::ext_explicit_instantiation_without_qualified_id)
5204 << Specialization << D.getCXXScopeSpec().getRange();
5206 CheckExplicitInstantiationScope(*this,
5207 FunTmpl? (NamedDecl *)FunTmpl
5208 : Specialization->getInstantiatedFromMemberFunction(),
5209 D.getIdentifierLoc(),
5210 D.getCXXScopeSpec().isSet());
5212 // FIXME: Create some kind of ExplicitInstantiationDecl here.
5217 Sema::ActOnDependentTag(Scope *S, unsigned TagSpec, TagUseKind TUK,
5218 const CXXScopeSpec &SS, IdentifierInfo *Name,
5219 SourceLocation TagLoc, SourceLocation NameLoc) {
5220 // This has to hold, because SS is expected to be defined.
5221 assert(Name && "Expected a name in a dependent tag");
5223 NestedNameSpecifier *NNS
5224 = static_cast<NestedNameSpecifier *>(SS.getScopeRep());
5228 TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec);
5230 if (TUK == TUK_Declaration || TUK == TUK_Definition) {
5231 Diag(NameLoc, diag::err_dependent_tag_decl)
5232 << (TUK == TUK_Definition) << Kind << SS.getRange();
5236 ElaboratedTypeKeyword Kwd = TypeWithKeyword::getKeywordForTagTypeKind(Kind);
5237 return ParsedType::make(Context.getDependentNameType(Kwd, NNS, Name));
5241 Sema::ActOnTypenameType(Scope *S, SourceLocation TypenameLoc,
5242 const CXXScopeSpec &SS, const IdentifierInfo &II,
5243 SourceLocation IdLoc) {
5244 NestedNameSpecifier *NNS
5245 = static_cast<NestedNameSpecifier *>(SS.getScopeRep());
5249 if (TypenameLoc.isValid() && S && !S->getTemplateParamParent() &&
5250 !getLangOptions().CPlusPlus0x)
5251 Diag(TypenameLoc, diag::ext_typename_outside_of_template)
5252 << FixItHint::CreateRemoval(TypenameLoc);
5254 QualType T = CheckTypenameType(ETK_Typename, NNS, II,
5255 TypenameLoc, SS.getRange(), IdLoc);
5259 TypeSourceInfo *TSI = Context.CreateTypeSourceInfo(T);
5260 if (isa<DependentNameType>(T)) {
5261 DependentNameTypeLoc TL = cast<DependentNameTypeLoc>(TSI->getTypeLoc());
5262 TL.setKeywordLoc(TypenameLoc);
5263 TL.setQualifierRange(SS.getRange());
5264 TL.setNameLoc(IdLoc);
5266 ElaboratedTypeLoc TL = cast<ElaboratedTypeLoc>(TSI->getTypeLoc());
5267 TL.setKeywordLoc(TypenameLoc);
5268 TL.setQualifierRange(SS.getRange());
5269 cast<TypeSpecTypeLoc>(TL.getNamedTypeLoc()).setNameLoc(IdLoc);
5272 return CreateParsedType(T, TSI);
5276 Sema::ActOnTypenameType(Scope *S, SourceLocation TypenameLoc,
5277 const CXXScopeSpec &SS, SourceLocation TemplateLoc,
5279 if (TypenameLoc.isValid() && S && !S->getTemplateParamParent() &&
5280 !getLangOptions().CPlusPlus0x)
5281 Diag(TypenameLoc, diag::ext_typename_outside_of_template)
5282 << FixItHint::CreateRemoval(TypenameLoc);
5284 TypeSourceInfo *InnerTSI = 0;
5285 QualType T = GetTypeFromParser(Ty, &InnerTSI);
5287 assert(isa<TemplateSpecializationType>(T) &&
5288 "Expected a template specialization type");
5290 if (computeDeclContext(SS, false)) {
5291 // If we can compute a declaration context, then the "typename"
5292 // keyword was superfluous. Just build an ElaboratedType to keep
5293 // track of the nested-name-specifier.
5295 // Push the inner type, preserving its source locations if possible.
5296 TypeLocBuilder Builder;
5298 Builder.pushFullCopy(InnerTSI->getTypeLoc());
5300 Builder.push<TemplateSpecializationTypeLoc>(T).initialize(TemplateLoc);
5302 /* Note: NNS already embedded in template specialization type T. */
5303 T = Context.getElaboratedType(ETK_Typename, /*NNS=*/0, T);
5304 ElaboratedTypeLoc TL = Builder.push<ElaboratedTypeLoc>(T);
5305 TL.setKeywordLoc(TypenameLoc);
5306 TL.setQualifierRange(SS.getRange());
5308 TypeSourceInfo *TSI = Builder.getTypeSourceInfo(Context, T);
5309 return CreateParsedType(T, TSI);
5312 // TODO: it's really silly that we make a template specialization
5313 // type earlier only to drop it again here.
5314 TemplateSpecializationType *TST = cast<TemplateSpecializationType>(T);
5315 DependentTemplateName *DTN =
5316 TST->getTemplateName().getAsDependentTemplateName();
5317 assert(DTN && "dependent template has non-dependent name?");
5318 assert(DTN->getQualifier()
5319 == static_cast<NestedNameSpecifier*>(SS.getScopeRep()));
5320 T = Context.getDependentTemplateSpecializationType(ETK_Typename,
5321 DTN->getQualifier(),
5322 DTN->getIdentifier(),
5325 TypeSourceInfo *TSI = Context.CreateTypeSourceInfo(T);
5326 DependentTemplateSpecializationTypeLoc TL =
5327 cast<DependentTemplateSpecializationTypeLoc>(TSI->getTypeLoc());
5329 TemplateSpecializationTypeLoc TSTL =
5330 cast<TemplateSpecializationTypeLoc>(InnerTSI->getTypeLoc());
5331 TL.setLAngleLoc(TSTL.getLAngleLoc());
5332 TL.setRAngleLoc(TSTL.getRAngleLoc());
5333 for (unsigned I = 0, E = TST->getNumArgs(); I != E; ++I)
5334 TL.setArgLocInfo(I, TSTL.getArgLocInfo(I));
5336 TL.initializeLocal(SourceLocation());
5338 TL.setKeywordLoc(TypenameLoc);
5339 TL.setQualifierRange(SS.getRange());
5340 return CreateParsedType(T, TSI);
5343 /// \brief Build the type that describes a C++ typename specifier,
5344 /// e.g., "typename T::type".
5346 Sema::CheckTypenameType(ElaboratedTypeKeyword Keyword,
5347 NestedNameSpecifier *NNS, const IdentifierInfo &II,
5348 SourceLocation KeywordLoc, SourceRange NNSRange,
5349 SourceLocation IILoc) {
5351 SS.setScopeRep(NNS);
5352 SS.setRange(NNSRange);
5354 DeclContext *Ctx = computeDeclContext(SS);
5356 // If the nested-name-specifier is dependent and couldn't be
5357 // resolved to a type, build a typename type.
5358 assert(NNS->isDependent());
5359 return Context.getDependentNameType(Keyword, NNS, &II);
5362 // If the nested-name-specifier refers to the current instantiation,
5363 // the "typename" keyword itself is superfluous. In C++03, the
5364 // program is actually ill-formed. However, DR 382 (in C++0x CD1)
5365 // allows such extraneous "typename" keywords, and we retroactively
5366 // apply this DR to C++03 code with only a warning. In any case we continue.
5368 if (RequireCompleteDeclContext(SS, Ctx))
5371 DeclarationName Name(&II);
5372 LookupResult Result(*this, Name, IILoc, LookupOrdinaryName);
5373 LookupQualifiedName(Result, Ctx);
5374 unsigned DiagID = 0;
5375 Decl *Referenced = 0;
5376 switch (Result.getResultKind()) {
5377 case LookupResult::NotFound:
5378 DiagID = diag::err_typename_nested_not_found;
5381 case LookupResult::NotFoundInCurrentInstantiation:
5382 // Okay, it's a member of an unknown instantiation.
5383 return Context.getDependentNameType(Keyword, NNS, &II);
5385 case LookupResult::Found:
5386 if (TypeDecl *Type = dyn_cast<TypeDecl>(Result.getFoundDecl())) {
5387 // We found a type. Build an ElaboratedType, since the
5388 // typename-specifier was just sugar.
5389 return Context.getElaboratedType(ETK_Typename, NNS,
5390 Context.getTypeDeclType(Type));
5393 DiagID = diag::err_typename_nested_not_type;
5394 Referenced = Result.getFoundDecl();
5397 case LookupResult::FoundUnresolvedValue:
5398 llvm_unreachable("unresolved using decl in non-dependent context");
5401 case LookupResult::FoundOverloaded:
5402 DiagID = diag::err_typename_nested_not_type;
5403 Referenced = *Result.begin();
5406 case LookupResult::Ambiguous:
5410 // If we get here, it's because name lookup did not find a
5411 // type. Emit an appropriate diagnostic and return an error.
5412 SourceRange FullRange(KeywordLoc.isValid() ? KeywordLoc : NNSRange.getBegin(),
5414 Diag(IILoc, DiagID) << FullRange << Name << Ctx;
5416 Diag(Referenced->getLocation(), diag::note_typename_refers_here)
5422 // See Sema::RebuildTypeInCurrentInstantiation
5423 class CurrentInstantiationRebuilder
5424 : public TreeTransform<CurrentInstantiationRebuilder> {
5426 DeclarationName Entity;
5429 typedef TreeTransform<CurrentInstantiationRebuilder> inherited;
5431 CurrentInstantiationRebuilder(Sema &SemaRef,
5433 DeclarationName Entity)
5434 : TreeTransform<CurrentInstantiationRebuilder>(SemaRef),
5435 Loc(Loc), Entity(Entity) { }
5437 /// \brief Determine whether the given type \p T has already been
5440 /// For the purposes of type reconstruction, a type has already been
5441 /// transformed if it is NULL or if it is not dependent.
5442 bool AlreadyTransformed(QualType T) {
5443 return T.isNull() || !T->isDependentType();
5446 /// \brief Returns the location of the entity whose type is being
5448 SourceLocation getBaseLocation() { return Loc; }
5450 /// \brief Returns the name of the entity whose type is being rebuilt.
5451 DeclarationName getBaseEntity() { return Entity; }
5453 /// \brief Sets the "base" location and entity when that
5454 /// information is known based on another transformation.
5455 void setBase(SourceLocation Loc, DeclarationName Entity) {
5457 this->Entity = Entity;
5462 /// \brief Rebuilds a type within the context of the current instantiation.
5464 /// The type \p T is part of the type of an out-of-line member definition of
5465 /// a class template (or class template partial specialization) that was parsed
5466 /// and constructed before we entered the scope of the class template (or
5467 /// partial specialization thereof). This routine will rebuild that type now
5468 /// that we have entered the declarator's scope, which may produce different
5469 /// canonical types, e.g.,
5472 /// template<typename T>
5474 /// typedef T* pointer;
5478 /// template<typename T>
5479 /// typename X<T>::pointer X<T>::data() { ... }
5482 /// Here, the type "typename X<T>::pointer" will be created as a DependentNameType,
5483 /// since we do not know that we can look into X<T> when we parsed the type.
5484 /// This function will rebuild the type, performing the lookup of "pointer"
5485 /// in X<T> and returning an ElaboratedType whose canonical type is the same
5486 /// as the canonical type of T*, allowing the return types of the out-of-line
5487 /// definition and the declaration to match.
5488 TypeSourceInfo *Sema::RebuildTypeInCurrentInstantiation(TypeSourceInfo *T,
5490 DeclarationName Name) {
5491 if (!T || !T->getType()->isDependentType())
5494 CurrentInstantiationRebuilder Rebuilder(*this, Loc, Name);
5495 return Rebuilder.TransformType(T);
5498 ExprResult Sema::RebuildExprInCurrentInstantiation(Expr *E) {
5499 CurrentInstantiationRebuilder Rebuilder(*this, E->getExprLoc(),
5501 return Rebuilder.TransformExpr(E);
5504 bool Sema::RebuildNestedNameSpecifierInCurrentInstantiation(CXXScopeSpec &SS) {
5505 if (SS.isInvalid()) return true;
5507 NestedNameSpecifier *NNS = static_cast<NestedNameSpecifier*>(SS.getScopeRep());
5508 CurrentInstantiationRebuilder Rebuilder(*this, SS.getRange().getBegin(),
5510 NestedNameSpecifier *Rebuilt =
5511 Rebuilder.TransformNestedNameSpecifier(NNS, SS.getRange());
5512 if (!Rebuilt) return true;
5514 SS.setScopeRep(Rebuilt);
5518 /// \brief Produces a formatted string that describes the binding of
5519 /// template parameters to template arguments.
5521 Sema::getTemplateArgumentBindingsText(const TemplateParameterList *Params,
5522 const TemplateArgumentList &Args) {
5523 // FIXME: For variadic templates, we'll need to get the structured list.
5524 return getTemplateArgumentBindingsText(Params, Args.getFlatArgumentList(),
5529 Sema::getTemplateArgumentBindingsText(const TemplateParameterList *Params,
5530 const TemplateArgument *Args,
5534 if (!Params || Params->size() == 0 || NumArgs == 0)
5537 for (unsigned I = 0, N = Params->size(); I != N; ++I) {
5546 if (const IdentifierInfo *Id = Params->getParam(I)->getIdentifier()) {
5547 Result += Id->getName();
5550 Result += llvm::utostr(I);
5555 switch (Args[I].getKind()) {
5556 case TemplateArgument::Null:
5557 Result += "<no value>";
5560 case TemplateArgument::Type: {
5561 std::string TypeStr;
5562 Args[I].getAsType().getAsStringInternal(TypeStr,
5563 Context.PrintingPolicy);
5568 case TemplateArgument::Declaration: {
5569 bool Unnamed = true;
5570 if (NamedDecl *ND = dyn_cast_or_null<NamedDecl>(Args[I].getAsDecl())) {
5571 if (ND->getDeclName()) {
5573 Result += ND->getNameAsString();
5578 Result += "<anonymous>";
5583 case TemplateArgument::Template: {
5585 llvm::raw_string_ostream OS(Str);
5586 Args[I].getAsTemplate().print(OS, Context.PrintingPolicy);
5591 case TemplateArgument::Integral: {
5592 Result += Args[I].getAsIntegral()->toString(10);
5596 case TemplateArgument::Expression: {
5597 // FIXME: This is non-optimal, since we're regurgitating the
5598 // expression we were given.
5601 llvm::raw_string_ostream OS(Str);
5602 Args[I].getAsExpr()->printPretty(OS, Context, 0,
5603 Context.PrintingPolicy);
5609 case TemplateArgument::Pack:
5610 // FIXME: Format template argument packs
5611 Result += "<template argument pack>";