1 //===------- SemaTemplate.cpp - Semantic Analysis for C++ Templates -------===/
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //===----------------------------------------------------------------------===/
9 // This file implements semantic analysis for C++ templates.
10 //===----------------------------------------------------------------------===/
12 #include "TreeTransform.h"
13 #include "clang/AST/ASTContext.h"
14 #include "clang/AST/DeclFriend.h"
15 #include "clang/AST/DeclTemplate.h"
16 #include "clang/AST/Expr.h"
17 #include "clang/AST/ExprCXX.h"
18 #include "clang/AST/RecursiveASTVisitor.h"
19 #include "clang/AST/TypeVisitor.h"
20 #include "clang/Basic/LangOptions.h"
21 #include "clang/Basic/PartialDiagnostic.h"
22 #include "clang/Sema/DeclSpec.h"
23 #include "clang/Sema/Lookup.h"
24 #include "clang/Sema/ParsedTemplate.h"
25 #include "clang/Sema/Scope.h"
26 #include "clang/Sema/SemaInternal.h"
27 #include "clang/Sema/Template.h"
28 #include "clang/Sema/TemplateDeduction.h"
29 #include "llvm/ADT/SmallBitVector.h"
30 #include "llvm/ADT/SmallString.h"
31 #include "llvm/ADT/StringExtras.h"
32 using namespace clang;
35 // Exported for use by Parser.
37 clang::getTemplateParamsRange(TemplateParameterList const * const *Ps,
39 if (!N) return SourceRange();
40 return SourceRange(Ps[0]->getTemplateLoc(), Ps[N-1]->getRAngleLoc());
43 /// \brief Determine whether the declaration found is acceptable as the name
44 /// of a template and, if so, return that template declaration. Otherwise,
46 static NamedDecl *isAcceptableTemplateName(ASTContext &Context,
48 bool AllowFunctionTemplates) {
49 NamedDecl *D = Orig->getUnderlyingDecl();
51 if (isa<TemplateDecl>(D)) {
52 if (!AllowFunctionTemplates && isa<FunctionTemplateDecl>(D))
58 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(D)) {
59 // C++ [temp.local]p1:
60 // Like normal (non-template) classes, class templates have an
61 // injected-class-name (Clause 9). The injected-class-name
62 // can be used with or without a template-argument-list. When
63 // it is used without a template-argument-list, it is
64 // equivalent to the injected-class-name followed by the
65 // template-parameters of the class template enclosed in
66 // <>. When it is used with a template-argument-list, it
67 // refers to the specified class template specialization,
68 // which could be the current specialization or another
70 if (Record->isInjectedClassName()) {
71 Record = cast<CXXRecordDecl>(Record->getDeclContext());
72 if (Record->getDescribedClassTemplate())
73 return Record->getDescribedClassTemplate();
75 if (ClassTemplateSpecializationDecl *Spec
76 = dyn_cast<ClassTemplateSpecializationDecl>(Record))
77 return Spec->getSpecializedTemplate();
86 void Sema::FilterAcceptableTemplateNames(LookupResult &R,
87 bool AllowFunctionTemplates) {
88 // The set of class templates we've already seen.
89 llvm::SmallPtrSet<ClassTemplateDecl *, 8> ClassTemplates;
90 LookupResult::Filter filter = R.makeFilter();
91 while (filter.hasNext()) {
92 NamedDecl *Orig = filter.next();
93 NamedDecl *Repl = isAcceptableTemplateName(Context, Orig,
94 AllowFunctionTemplates);
97 else if (Repl != Orig) {
99 // C++ [temp.local]p3:
100 // A lookup that finds an injected-class-name (10.2) can result in an
101 // ambiguity in certain cases (for example, if it is found in more than
102 // one base class). If all of the injected-class-names that are found
103 // refer to specializations of the same class template, and if the name
104 // is used as a template-name, the reference refers to the class
105 // template itself and not a specialization thereof, and is not
107 if (ClassTemplateDecl *ClassTmpl = dyn_cast<ClassTemplateDecl>(Repl))
108 if (!ClassTemplates.insert(ClassTmpl)) {
113 // FIXME: we promote access to public here as a workaround to
114 // the fact that LookupResult doesn't let us remember that we
115 // found this template through a particular injected class name,
116 // which means we end up doing nasty things to the invariants.
117 // Pretending that access is public is *much* safer.
118 filter.replace(Repl, AS_public);
124 bool Sema::hasAnyAcceptableTemplateNames(LookupResult &R,
125 bool AllowFunctionTemplates) {
126 for (LookupResult::iterator I = R.begin(), IEnd = R.end(); I != IEnd; ++I)
127 if (isAcceptableTemplateName(Context, *I, AllowFunctionTemplates))
133 TemplateNameKind Sema::isTemplateName(Scope *S,
135 bool hasTemplateKeyword,
137 ParsedType ObjectTypePtr,
138 bool EnteringContext,
139 TemplateTy &TemplateResult,
140 bool &MemberOfUnknownSpecialization) {
141 assert(getLangOpts().CPlusPlus && "No template names in C!");
143 DeclarationName TName;
144 MemberOfUnknownSpecialization = false;
146 switch (Name.getKind()) {
147 case UnqualifiedId::IK_Identifier:
148 TName = DeclarationName(Name.Identifier);
151 case UnqualifiedId::IK_OperatorFunctionId:
152 TName = Context.DeclarationNames.getCXXOperatorName(
153 Name.OperatorFunctionId.Operator);
156 case UnqualifiedId::IK_LiteralOperatorId:
157 TName = Context.DeclarationNames.getCXXLiteralOperatorName(Name.Identifier);
161 return TNK_Non_template;
164 QualType ObjectType = ObjectTypePtr.get();
166 LookupResult R(*this, TName, Name.getLocStart(), LookupOrdinaryName);
167 LookupTemplateName(R, S, SS, ObjectType, EnteringContext,
168 MemberOfUnknownSpecialization);
169 if (R.empty()) return TNK_Non_template;
170 if (R.isAmbiguous()) {
171 // Suppress diagnostics; we'll redo this lookup later.
172 R.suppressDiagnostics();
174 // FIXME: we might have ambiguous templates, in which case we
175 // should at least parse them properly!
176 return TNK_Non_template;
179 TemplateName Template;
180 TemplateNameKind TemplateKind;
182 unsigned ResultCount = R.end() - R.begin();
183 if (ResultCount > 1) {
184 // We assume that we'll preserve the qualifier from a function
185 // template name in other ways.
186 Template = Context.getOverloadedTemplateName(R.begin(), R.end());
187 TemplateKind = TNK_Function_template;
189 // We'll do this lookup again later.
190 R.suppressDiagnostics();
192 TemplateDecl *TD = cast<TemplateDecl>((*R.begin())->getUnderlyingDecl());
194 if (SS.isSet() && !SS.isInvalid()) {
195 NestedNameSpecifier *Qualifier
196 = static_cast<NestedNameSpecifier *>(SS.getScopeRep());
197 Template = Context.getQualifiedTemplateName(Qualifier,
198 hasTemplateKeyword, TD);
200 Template = TemplateName(TD);
203 if (isa<FunctionTemplateDecl>(TD)) {
204 TemplateKind = TNK_Function_template;
206 // We'll do this lookup again later.
207 R.suppressDiagnostics();
209 assert(isa<ClassTemplateDecl>(TD) || isa<TemplateTemplateParmDecl>(TD) ||
210 isa<TypeAliasTemplateDecl>(TD));
211 TemplateKind = TNK_Type_template;
215 TemplateResult = TemplateTy::make(Template);
219 bool Sema::DiagnoseUnknownTemplateName(const IdentifierInfo &II,
220 SourceLocation IILoc,
222 const CXXScopeSpec *SS,
223 TemplateTy &SuggestedTemplate,
224 TemplateNameKind &SuggestedKind) {
225 // We can't recover unless there's a dependent scope specifier preceding the
227 // FIXME: Typo correction?
228 if (!SS || !SS->isSet() || !isDependentScopeSpecifier(*SS) ||
229 computeDeclContext(*SS))
232 // The code is missing a 'template' keyword prior to the dependent template
234 NestedNameSpecifier *Qualifier = (NestedNameSpecifier*)SS->getScopeRep();
235 Diag(IILoc, diag::err_template_kw_missing)
236 << Qualifier << II.getName()
237 << FixItHint::CreateInsertion(IILoc, "template ");
239 = TemplateTy::make(Context.getDependentTemplateName(Qualifier, &II));
240 SuggestedKind = TNK_Dependent_template_name;
244 void Sema::LookupTemplateName(LookupResult &Found,
245 Scope *S, CXXScopeSpec &SS,
247 bool EnteringContext,
248 bool &MemberOfUnknownSpecialization) {
249 // Determine where to perform name lookup
250 MemberOfUnknownSpecialization = false;
251 DeclContext *LookupCtx = 0;
252 bool isDependent = false;
253 if (!ObjectType.isNull()) {
254 // This nested-name-specifier occurs in a member access expression, e.g.,
255 // x->B::f, and we are looking into the type of the object.
256 assert(!SS.isSet() && "ObjectType and scope specifier cannot coexist");
257 LookupCtx = computeDeclContext(ObjectType);
258 isDependent = ObjectType->isDependentType();
259 assert((isDependent || !ObjectType->isIncompleteType()) &&
260 "Caller should have completed object type");
262 // Template names cannot appear inside an Objective-C class or object type.
263 if (ObjectType->isObjCObjectOrInterfaceType()) {
267 } else if (SS.isSet()) {
268 // This nested-name-specifier occurs after another nested-name-specifier,
269 // so long into the context associated with the prior nested-name-specifier.
270 LookupCtx = computeDeclContext(SS, EnteringContext);
271 isDependent = isDependentScopeSpecifier(SS);
273 // The declaration context must be complete.
274 if (LookupCtx && RequireCompleteDeclContext(SS, LookupCtx))
278 bool ObjectTypeSearchedInScope = false;
279 bool AllowFunctionTemplatesInLookup = true;
281 // Perform "qualified" name lookup into the declaration context we
282 // computed, which is either the type of the base of a member access
283 // expression or the declaration context associated with a prior
284 // nested-name-specifier.
285 LookupQualifiedName(Found, LookupCtx);
286 if (!ObjectType.isNull() && Found.empty()) {
287 // C++ [basic.lookup.classref]p1:
288 // In a class member access expression (5.2.5), if the . or -> token is
289 // immediately followed by an identifier followed by a <, the
290 // identifier must be looked up to determine whether the < is the
291 // beginning of a template argument list (14.2) or a less-than operator.
292 // The identifier is first looked up in the class of the object
293 // expression. If the identifier is not found, it is then looked up in
294 // the context of the entire postfix-expression and shall name a class
295 // or function template.
296 if (S) LookupName(Found, S);
297 ObjectTypeSearchedInScope = true;
298 AllowFunctionTemplatesInLookup = false;
300 } else if (isDependent && (!S || ObjectType.isNull())) {
301 // We cannot look into a dependent object type or nested nme
303 MemberOfUnknownSpecialization = true;
306 // Perform unqualified name lookup in the current scope.
307 LookupName(Found, S);
309 if (!ObjectType.isNull())
310 AllowFunctionTemplatesInLookup = false;
313 if (Found.empty() && !isDependent) {
314 // If we did not find any names, attempt to correct any typos.
315 DeclarationName Name = Found.getLookupName();
317 // Simple filter callback that, for keywords, only accepts the C++ *_cast
318 CorrectionCandidateCallback FilterCCC;
319 FilterCCC.WantTypeSpecifiers = false;
320 FilterCCC.WantExpressionKeywords = false;
321 FilterCCC.WantRemainingKeywords = false;
322 FilterCCC.WantCXXNamedCasts = true;
323 if (TypoCorrection Corrected = CorrectTypo(Found.getLookupNameInfo(),
324 Found.getLookupKind(), S, &SS,
325 FilterCCC, LookupCtx)) {
326 Found.setLookupName(Corrected.getCorrection());
327 if (Corrected.getCorrectionDecl())
328 Found.addDecl(Corrected.getCorrectionDecl());
329 FilterAcceptableTemplateNames(Found);
330 if (!Found.empty()) {
331 std::string CorrectedStr(Corrected.getAsString(getLangOpts()));
332 std::string CorrectedQuotedStr(Corrected.getQuoted(getLangOpts()));
334 Diag(Found.getNameLoc(), diag::err_no_member_template_suggest)
335 << Name << LookupCtx << CorrectedQuotedStr << SS.getRange()
336 << FixItHint::CreateReplacement(Corrected.getCorrectionRange(),
339 Diag(Found.getNameLoc(), diag::err_no_template_suggest)
340 << Name << CorrectedQuotedStr
341 << FixItHint::CreateReplacement(Found.getNameLoc(), CorrectedStr);
342 if (TemplateDecl *Template = Found.getAsSingle<TemplateDecl>())
343 Diag(Template->getLocation(), diag::note_previous_decl)
344 << CorrectedQuotedStr;
347 Found.setLookupName(Name);
351 FilterAcceptableTemplateNames(Found, AllowFunctionTemplatesInLookup);
354 MemberOfUnknownSpecialization = true;
358 if (S && !ObjectType.isNull() && !ObjectTypeSearchedInScope &&
359 !(getLangOpts().CPlusPlus11 && !Found.empty())) {
360 // C++03 [basic.lookup.classref]p1:
361 // [...] If the lookup in the class of the object expression finds a
362 // template, the name is also looked up in the context of the entire
363 // postfix-expression and [...]
365 // Note: C++11 does not perform this second lookup.
366 LookupResult FoundOuter(*this, Found.getLookupName(), Found.getNameLoc(),
368 LookupName(FoundOuter, S);
369 FilterAcceptableTemplateNames(FoundOuter, /*AllowFunctionTemplates=*/false);
371 if (FoundOuter.empty()) {
372 // - if the name is not found, the name found in the class of the
373 // object expression is used, otherwise
374 } else if (!FoundOuter.getAsSingle<ClassTemplateDecl>() ||
375 FoundOuter.isAmbiguous()) {
376 // - if the name is found in the context of the entire
377 // postfix-expression and does not name a class template, the name
378 // found in the class of the object expression is used, otherwise
380 } else if (!Found.isSuppressingDiagnostics()) {
381 // - if the name found is a class template, it must refer to the same
382 // entity as the one found in the class of the object expression,
383 // otherwise the program is ill-formed.
384 if (!Found.isSingleResult() ||
385 Found.getFoundDecl()->getCanonicalDecl()
386 != FoundOuter.getFoundDecl()->getCanonicalDecl()) {
387 Diag(Found.getNameLoc(),
388 diag::ext_nested_name_member_ref_lookup_ambiguous)
389 << Found.getLookupName()
391 Diag(Found.getRepresentativeDecl()->getLocation(),
392 diag::note_ambig_member_ref_object_type)
394 Diag(FoundOuter.getFoundDecl()->getLocation(),
395 diag::note_ambig_member_ref_scope);
397 // Recover by taking the template that we found in the object
398 // expression's type.
404 /// ActOnDependentIdExpression - Handle a dependent id-expression that
405 /// was just parsed. This is only possible with an explicit scope
406 /// specifier naming a dependent type.
408 Sema::ActOnDependentIdExpression(const CXXScopeSpec &SS,
409 SourceLocation TemplateKWLoc,
410 const DeclarationNameInfo &NameInfo,
411 bool isAddressOfOperand,
412 const TemplateArgumentListInfo *TemplateArgs) {
413 DeclContext *DC = getFunctionLevelDeclContext();
415 if (!isAddressOfOperand &&
416 isa<CXXMethodDecl>(DC) &&
417 cast<CXXMethodDecl>(DC)->isInstance()) {
418 QualType ThisType = cast<CXXMethodDecl>(DC)->getThisType(Context);
420 // Since the 'this' expression is synthesized, we don't need to
421 // perform the double-lookup check.
422 NamedDecl *FirstQualifierInScope = 0;
424 return Owned(CXXDependentScopeMemberExpr::Create(Context,
425 /*This*/ 0, ThisType,
427 /*Op*/ SourceLocation(),
428 SS.getWithLocInContext(Context),
430 FirstQualifierInScope,
435 return BuildDependentDeclRefExpr(SS, TemplateKWLoc, NameInfo, TemplateArgs);
439 Sema::BuildDependentDeclRefExpr(const CXXScopeSpec &SS,
440 SourceLocation TemplateKWLoc,
441 const DeclarationNameInfo &NameInfo,
442 const TemplateArgumentListInfo *TemplateArgs) {
443 return Owned(DependentScopeDeclRefExpr::Create(Context,
444 SS.getWithLocInContext(Context),
450 /// DiagnoseTemplateParameterShadow - Produce a diagnostic complaining
451 /// that the template parameter 'PrevDecl' is being shadowed by a new
452 /// declaration at location Loc. Returns true to indicate that this is
453 /// an error, and false otherwise.
454 void Sema::DiagnoseTemplateParameterShadow(SourceLocation Loc, Decl *PrevDecl) {
455 assert(PrevDecl->isTemplateParameter() && "Not a template parameter");
457 // Microsoft Visual C++ permits template parameters to be shadowed.
458 if (getLangOpts().MicrosoftExt)
461 // C++ [temp.local]p4:
462 // A template-parameter shall not be redeclared within its
463 // scope (including nested scopes).
464 Diag(Loc, diag::err_template_param_shadow)
465 << cast<NamedDecl>(PrevDecl)->getDeclName();
466 Diag(PrevDecl->getLocation(), diag::note_template_param_here);
470 /// AdjustDeclIfTemplate - If the given decl happens to be a template, reset
471 /// the parameter D to reference the templated declaration and return a pointer
472 /// to the template declaration. Otherwise, do nothing to D and return null.
473 TemplateDecl *Sema::AdjustDeclIfTemplate(Decl *&D) {
474 if (TemplateDecl *Temp = dyn_cast_or_null<TemplateDecl>(D)) {
475 D = Temp->getTemplatedDecl();
481 ParsedTemplateArgument ParsedTemplateArgument::getTemplatePackExpansion(
482 SourceLocation EllipsisLoc) const {
483 assert(Kind == Template &&
484 "Only template template arguments can be pack expansions here");
485 assert(getAsTemplate().get().containsUnexpandedParameterPack() &&
486 "Template template argument pack expansion without packs");
487 ParsedTemplateArgument Result(*this);
488 Result.EllipsisLoc = EllipsisLoc;
492 static TemplateArgumentLoc translateTemplateArgument(Sema &SemaRef,
493 const ParsedTemplateArgument &Arg) {
495 switch (Arg.getKind()) {
496 case ParsedTemplateArgument::Type: {
498 QualType T = SemaRef.GetTypeFromParser(Arg.getAsType(), &DI);
500 DI = SemaRef.Context.getTrivialTypeSourceInfo(T, Arg.getLocation());
501 return TemplateArgumentLoc(TemplateArgument(T), DI);
504 case ParsedTemplateArgument::NonType: {
505 Expr *E = static_cast<Expr *>(Arg.getAsExpr());
506 return TemplateArgumentLoc(TemplateArgument(E), E);
509 case ParsedTemplateArgument::Template: {
510 TemplateName Template = Arg.getAsTemplate().get();
511 TemplateArgument TArg;
512 if (Arg.getEllipsisLoc().isValid())
513 TArg = TemplateArgument(Template, Optional<unsigned int>());
516 return TemplateArgumentLoc(TArg,
517 Arg.getScopeSpec().getWithLocInContext(
520 Arg.getEllipsisLoc());
524 llvm_unreachable("Unhandled parsed template argument");
527 /// \brief Translates template arguments as provided by the parser
528 /// into template arguments used by semantic analysis.
529 void Sema::translateTemplateArguments(const ASTTemplateArgsPtr &TemplateArgsIn,
530 TemplateArgumentListInfo &TemplateArgs) {
531 for (unsigned I = 0, Last = TemplateArgsIn.size(); I != Last; ++I)
532 TemplateArgs.addArgument(translateTemplateArgument(*this,
536 /// ActOnTypeParameter - Called when a C++ template type parameter
537 /// (e.g., "typename T") has been parsed. Typename specifies whether
538 /// the keyword "typename" was used to declare the type parameter
539 /// (otherwise, "class" was used), and KeyLoc is the location of the
540 /// "class" or "typename" keyword. ParamName is the name of the
541 /// parameter (NULL indicates an unnamed template parameter) and
542 /// ParamNameLoc is the location of the parameter name (if any).
543 /// If the type parameter has a default argument, it will be added
544 /// later via ActOnTypeParameterDefault.
545 Decl *Sema::ActOnTypeParameter(Scope *S, bool Typename, bool Ellipsis,
546 SourceLocation EllipsisLoc,
547 SourceLocation KeyLoc,
548 IdentifierInfo *ParamName,
549 SourceLocation ParamNameLoc,
550 unsigned Depth, unsigned Position,
551 SourceLocation EqualLoc,
552 ParsedType DefaultArg) {
553 assert(S->isTemplateParamScope() &&
554 "Template type parameter not in template parameter scope!");
555 bool Invalid = false;
558 NamedDecl *PrevDecl = LookupSingleName(S, ParamName, ParamNameLoc,
561 if (PrevDecl && PrevDecl->isTemplateParameter()) {
562 DiagnoseTemplateParameterShadow(ParamNameLoc, PrevDecl);
567 SourceLocation Loc = ParamNameLoc;
571 TemplateTypeParmDecl *Param
572 = TemplateTypeParmDecl::Create(Context, Context.getTranslationUnitDecl(),
573 KeyLoc, Loc, Depth, Position, ParamName,
575 Param->setAccess(AS_public);
577 Param->setInvalidDecl();
580 // Add the template parameter into the current scope.
582 IdResolver.AddDecl(Param);
585 // C++0x [temp.param]p9:
586 // A default template-argument may be specified for any kind of
587 // template-parameter that is not a template parameter pack.
588 if (DefaultArg && Ellipsis) {
589 Diag(EqualLoc, diag::err_template_param_pack_default_arg);
590 DefaultArg = ParsedType();
593 // Handle the default argument, if provided.
595 TypeSourceInfo *DefaultTInfo;
596 GetTypeFromParser(DefaultArg, &DefaultTInfo);
598 assert(DefaultTInfo && "expected source information for type");
600 // Check for unexpanded parameter packs.
601 if (DiagnoseUnexpandedParameterPack(Loc, DefaultTInfo,
602 UPPC_DefaultArgument))
605 // Check the template argument itself.
606 if (CheckTemplateArgument(Param, DefaultTInfo)) {
607 Param->setInvalidDecl();
611 Param->setDefaultArgument(DefaultTInfo, false);
617 /// \brief Check that the type of a non-type template parameter is
620 /// \returns the (possibly-promoted) parameter type if valid;
621 /// otherwise, produces a diagnostic and returns a NULL type.
623 Sema::CheckNonTypeTemplateParameterType(QualType T, SourceLocation Loc) {
624 // We don't allow variably-modified types as the type of non-type template
626 if (T->isVariablyModifiedType()) {
627 Diag(Loc, diag::err_variably_modified_nontype_template_param)
632 // C++ [temp.param]p4:
634 // A non-type template-parameter shall have one of the following
635 // (optionally cv-qualified) types:
637 // -- integral or enumeration type,
638 if (T->isIntegralOrEnumerationType() ||
639 // -- pointer to object or pointer to function,
640 T->isPointerType() ||
641 // -- reference to object or reference to function,
642 T->isReferenceType() ||
643 // -- pointer to member,
644 T->isMemberPointerType() ||
645 // -- std::nullptr_t.
646 T->isNullPtrType() ||
647 // If T is a dependent type, we can't do the check now, so we
648 // assume that it is well-formed.
649 T->isDependentType()) {
650 // C++ [temp.param]p5: The top-level cv-qualifiers on the template-parameter
651 // are ignored when determining its type.
652 return T.getUnqualifiedType();
655 // C++ [temp.param]p8:
657 // A non-type template-parameter of type "array of T" or
658 // "function returning T" is adjusted to be of type "pointer to
659 // T" or "pointer to function returning T", respectively.
660 else if (T->isArrayType())
661 // FIXME: Keep the type prior to promotion?
662 return Context.getArrayDecayedType(T);
663 else if (T->isFunctionType())
664 // FIXME: Keep the type prior to promotion?
665 return Context.getPointerType(T);
667 Diag(Loc, diag::err_template_nontype_parm_bad_type)
673 Decl *Sema::ActOnNonTypeTemplateParameter(Scope *S, Declarator &D,
676 SourceLocation EqualLoc,
678 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S);
679 QualType T = TInfo->getType();
681 assert(S->isTemplateParamScope() &&
682 "Non-type template parameter not in template parameter scope!");
683 bool Invalid = false;
685 IdentifierInfo *ParamName = D.getIdentifier();
687 NamedDecl *PrevDecl = LookupSingleName(S, ParamName, D.getIdentifierLoc(),
690 if (PrevDecl && PrevDecl->isTemplateParameter()) {
691 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl);
696 T = CheckNonTypeTemplateParameterType(T, D.getIdentifierLoc());
698 T = Context.IntTy; // Recover with an 'int' type.
702 bool IsParameterPack = D.hasEllipsis();
703 NonTypeTemplateParmDecl *Param
704 = NonTypeTemplateParmDecl::Create(Context, Context.getTranslationUnitDecl(),
706 D.getIdentifierLoc(),
707 Depth, Position, ParamName, T,
708 IsParameterPack, TInfo);
709 Param->setAccess(AS_public);
712 Param->setInvalidDecl();
714 if (D.getIdentifier()) {
715 // Add the template parameter into the current scope.
717 IdResolver.AddDecl(Param);
720 // C++0x [temp.param]p9:
721 // A default template-argument may be specified for any kind of
722 // template-parameter that is not a template parameter pack.
723 if (Default && IsParameterPack) {
724 Diag(EqualLoc, diag::err_template_param_pack_default_arg);
728 // Check the well-formedness of the default template argument, if provided.
730 // Check for unexpanded parameter packs.
731 if (DiagnoseUnexpandedParameterPack(Default, UPPC_DefaultArgument))
734 TemplateArgument Converted;
735 ExprResult DefaultRes = CheckTemplateArgument(Param, Param->getType(), Default, Converted);
736 if (DefaultRes.isInvalid()) {
737 Param->setInvalidDecl();
740 Default = DefaultRes.take();
742 Param->setDefaultArgument(Default, false);
748 /// ActOnTemplateTemplateParameter - Called when a C++ template template
749 /// parameter (e.g. T in template <template \<typename> class T> class array)
750 /// has been parsed. S is the current scope.
751 Decl *Sema::ActOnTemplateTemplateParameter(Scope* S,
752 SourceLocation TmpLoc,
753 TemplateParameterList *Params,
754 SourceLocation EllipsisLoc,
755 IdentifierInfo *Name,
756 SourceLocation NameLoc,
759 SourceLocation EqualLoc,
760 ParsedTemplateArgument Default) {
761 assert(S->isTemplateParamScope() &&
762 "Template template parameter not in template parameter scope!");
764 // Construct the parameter object.
765 bool IsParameterPack = EllipsisLoc.isValid();
766 TemplateTemplateParmDecl *Param =
767 TemplateTemplateParmDecl::Create(Context, Context.getTranslationUnitDecl(),
768 NameLoc.isInvalid()? TmpLoc : NameLoc,
769 Depth, Position, IsParameterPack,
771 Param->setAccess(AS_public);
773 // If the template template parameter has a name, then link the identifier
774 // into the scope and lookup mechanisms.
777 IdResolver.AddDecl(Param);
780 if (Params->size() == 0) {
781 Diag(Param->getLocation(), diag::err_template_template_parm_no_parms)
782 << SourceRange(Params->getLAngleLoc(), Params->getRAngleLoc());
783 Param->setInvalidDecl();
786 // C++0x [temp.param]p9:
787 // A default template-argument may be specified for any kind of
788 // template-parameter that is not a template parameter pack.
789 if (IsParameterPack && !Default.isInvalid()) {
790 Diag(EqualLoc, diag::err_template_param_pack_default_arg);
791 Default = ParsedTemplateArgument();
794 if (!Default.isInvalid()) {
795 // Check only that we have a template template argument. We don't want to
796 // try to check well-formedness now, because our template template parameter
797 // might have dependent types in its template parameters, which we wouldn't
798 // be able to match now.
800 // If none of the template template parameter's template arguments mention
801 // other template parameters, we could actually perform more checking here.
802 // However, it isn't worth doing.
803 TemplateArgumentLoc DefaultArg = translateTemplateArgument(*this, Default);
804 if (DefaultArg.getArgument().getAsTemplate().isNull()) {
805 Diag(DefaultArg.getLocation(), diag::err_template_arg_not_class_template)
806 << DefaultArg.getSourceRange();
810 // Check for unexpanded parameter packs.
811 if (DiagnoseUnexpandedParameterPack(DefaultArg.getLocation(),
812 DefaultArg.getArgument().getAsTemplate(),
813 UPPC_DefaultArgument))
816 Param->setDefaultArgument(DefaultArg, false);
822 /// ActOnTemplateParameterList - Builds a TemplateParameterList that
823 /// contains the template parameters in Params/NumParams.
824 TemplateParameterList *
825 Sema::ActOnTemplateParameterList(unsigned Depth,
826 SourceLocation ExportLoc,
827 SourceLocation TemplateLoc,
828 SourceLocation LAngleLoc,
829 Decl **Params, unsigned NumParams,
830 SourceLocation RAngleLoc) {
831 if (ExportLoc.isValid())
832 Diag(ExportLoc, diag::warn_template_export_unsupported);
834 return TemplateParameterList::Create(Context, TemplateLoc, LAngleLoc,
835 (NamedDecl**)Params, NumParams,
839 static void SetNestedNameSpecifier(TagDecl *T, const CXXScopeSpec &SS) {
841 T->setQualifierInfo(SS.getWithLocInContext(T->getASTContext()));
845 Sema::CheckClassTemplate(Scope *S, unsigned TagSpec, TagUseKind TUK,
846 SourceLocation KWLoc, CXXScopeSpec &SS,
847 IdentifierInfo *Name, SourceLocation NameLoc,
849 TemplateParameterList *TemplateParams,
850 AccessSpecifier AS, SourceLocation ModulePrivateLoc,
851 unsigned NumOuterTemplateParamLists,
852 TemplateParameterList** OuterTemplateParamLists) {
853 assert(TemplateParams && TemplateParams->size() > 0 &&
854 "No template parameters");
855 assert(TUK != TUK_Reference && "Can only declare or define class templates");
856 bool Invalid = false;
858 // Check that we can declare a template here.
859 if (CheckTemplateDeclScope(S, TemplateParams))
862 TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec);
863 assert(Kind != TTK_Enum && "can't build template of enumerated type");
865 // There is no such thing as an unnamed class template.
867 Diag(KWLoc, diag::err_template_unnamed_class);
871 // Find any previous declaration with this name. For a friend with no
872 // scope explicitly specified, we only look for tag declarations (per
873 // C++11 [basic.lookup.elab]p2).
874 DeclContext *SemanticContext;
875 LookupResult Previous(*this, Name, NameLoc,
876 (SS.isEmpty() && TUK == TUK_Friend)
877 ? LookupTagName : LookupOrdinaryName,
879 if (SS.isNotEmpty() && !SS.isInvalid()) {
880 SemanticContext = computeDeclContext(SS, true);
881 if (!SemanticContext) {
882 // FIXME: Horrible, horrible hack! We can't currently represent this
883 // in the AST, and historically we have just ignored such friend
884 // class templates, so don't complain here.
885 if (TUK != TUK_Friend)
886 Diag(NameLoc, diag::err_template_qualified_declarator_no_match)
887 << SS.getScopeRep() << SS.getRange();
891 if (RequireCompleteDeclContext(SS, SemanticContext))
894 // If we're adding a template to a dependent context, we may need to
895 // rebuilding some of the types used within the template parameter list,
896 // now that we know what the current instantiation is.
897 if (SemanticContext->isDependentContext()) {
898 ContextRAII SavedContext(*this, SemanticContext);
899 if (RebuildTemplateParamsInCurrentInstantiation(TemplateParams))
901 } else if (TUK != TUK_Friend && TUK != TUK_Reference)
902 diagnoseQualifiedDeclaration(SS, SemanticContext, Name, NameLoc);
904 LookupQualifiedName(Previous, SemanticContext);
906 SemanticContext = CurContext;
907 LookupName(Previous, S);
910 if (Previous.isAmbiguous())
913 NamedDecl *PrevDecl = 0;
914 if (Previous.begin() != Previous.end())
915 PrevDecl = (*Previous.begin())->getUnderlyingDecl();
917 // If there is a previous declaration with the same name, check
918 // whether this is a valid redeclaration.
919 ClassTemplateDecl *PrevClassTemplate
920 = dyn_cast_or_null<ClassTemplateDecl>(PrevDecl);
922 // We may have found the injected-class-name of a class template,
923 // class template partial specialization, or class template specialization.
924 // In these cases, grab the template that is being defined or specialized.
925 if (!PrevClassTemplate && PrevDecl && isa<CXXRecordDecl>(PrevDecl) &&
926 cast<CXXRecordDecl>(PrevDecl)->isInjectedClassName()) {
927 PrevDecl = cast<CXXRecordDecl>(PrevDecl->getDeclContext());
929 = cast<CXXRecordDecl>(PrevDecl)->getDescribedClassTemplate();
930 if (!PrevClassTemplate && isa<ClassTemplateSpecializationDecl>(PrevDecl)) {
932 = cast<ClassTemplateSpecializationDecl>(PrevDecl)
933 ->getSpecializedTemplate();
937 if (TUK == TUK_Friend) {
938 // C++ [namespace.memdef]p3:
939 // [...] When looking for a prior declaration of a class or a function
940 // declared as a friend, and when the name of the friend class or
941 // function is neither a qualified name nor a template-id, scopes outside
942 // the innermost enclosing namespace scope are not considered.
944 DeclContext *OutermostContext = CurContext;
945 while (!OutermostContext->isFileContext())
946 OutermostContext = OutermostContext->getLookupParent();
949 (OutermostContext->Equals(PrevDecl->getDeclContext()) ||
950 OutermostContext->Encloses(PrevDecl->getDeclContext()))) {
951 SemanticContext = PrevDecl->getDeclContext();
953 // Declarations in outer scopes don't matter. However, the outermost
954 // context we computed is the semantic context for our new
956 PrevDecl = PrevClassTemplate = 0;
957 SemanticContext = OutermostContext;
959 // Check that the chosen semantic context doesn't already contain a
960 // declaration of this name as a non-tag type.
961 LookupResult Previous(*this, Name, NameLoc, LookupOrdinaryName,
963 DeclContext *LookupContext = SemanticContext;
964 while (LookupContext->isTransparentContext())
965 LookupContext = LookupContext->getLookupParent();
966 LookupQualifiedName(Previous, LookupContext);
968 if (Previous.isAmbiguous())
971 if (Previous.begin() != Previous.end())
972 PrevDecl = (*Previous.begin())->getUnderlyingDecl();
975 } else if (PrevDecl && !isDeclInScope(PrevDecl, SemanticContext, S))
976 PrevDecl = PrevClassTemplate = 0;
978 if (PrevClassTemplate) {
979 // Ensure that the template parameter lists are compatible. Skip this check
980 // for a friend in a dependent context: the template parameter list itself
981 // could be dependent.
982 if (!(TUK == TUK_Friend && CurContext->isDependentContext()) &&
983 !TemplateParameterListsAreEqual(TemplateParams,
984 PrevClassTemplate->getTemplateParameters(),
989 // C++ [temp.class]p4:
990 // In a redeclaration, partial specialization, explicit
991 // specialization or explicit instantiation of a class template,
992 // the class-key shall agree in kind with the original class
993 // template declaration (7.1.5.3).
994 RecordDecl *PrevRecordDecl = PrevClassTemplate->getTemplatedDecl();
995 if (!isAcceptableTagRedeclaration(PrevRecordDecl, Kind,
996 TUK == TUK_Definition, KWLoc, *Name)) {
997 Diag(KWLoc, diag::err_use_with_wrong_tag)
999 << FixItHint::CreateReplacement(KWLoc, PrevRecordDecl->getKindName());
1000 Diag(PrevRecordDecl->getLocation(), diag::note_previous_use);
1001 Kind = PrevRecordDecl->getTagKind();
1004 // Check for redefinition of this class template.
1005 if (TUK == TUK_Definition) {
1006 if (TagDecl *Def = PrevRecordDecl->getDefinition()) {
1007 Diag(NameLoc, diag::err_redefinition) << Name;
1008 Diag(Def->getLocation(), diag::note_previous_definition);
1009 // FIXME: Would it make sense to try to "forget" the previous
1010 // definition, as part of error recovery?
1014 } else if (PrevDecl && PrevDecl->isTemplateParameter()) {
1015 // Maybe we will complain about the shadowed template parameter.
1016 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl);
1017 // Just pretend that we didn't see the previous declaration.
1019 } else if (PrevDecl) {
1021 // A class template shall not have the same name as any other
1022 // template, class, function, object, enumeration, enumerator,
1023 // namespace, or type in the same scope (3.3), except as specified
1025 Diag(NameLoc, diag::err_redefinition_different_kind) << Name;
1026 Diag(PrevDecl->getLocation(), diag::note_previous_definition);
1030 // Check the template parameter list of this declaration, possibly
1031 // merging in the template parameter list from the previous class
1032 // template declaration. Skip this check for a friend in a dependent
1033 // context, because the template parameter list might be dependent.
1034 if (!(TUK == TUK_Friend && CurContext->isDependentContext()) &&
1035 CheckTemplateParameterList(TemplateParams,
1036 PrevClassTemplate? PrevClassTemplate->getTemplateParameters() : 0,
1037 (SS.isSet() && SemanticContext &&
1038 SemanticContext->isRecord() &&
1039 SemanticContext->isDependentContext())
1040 ? TPC_ClassTemplateMember
1041 : TPC_ClassTemplate))
1045 // If the name of the template was qualified, we must be defining the
1046 // template out-of-line.
1047 if (!SS.isInvalid() && !Invalid && !PrevClassTemplate) {
1048 Diag(NameLoc, TUK == TUK_Friend ? diag::err_friend_decl_does_not_match
1049 : diag::err_member_def_does_not_match)
1050 << Name << SemanticContext << SS.getRange();
1055 CXXRecordDecl *NewClass =
1056 CXXRecordDecl::Create(Context, Kind, SemanticContext, KWLoc, NameLoc, Name,
1058 PrevClassTemplate->getTemplatedDecl() : 0,
1059 /*DelayTypeCreation=*/true);
1060 SetNestedNameSpecifier(NewClass, SS);
1061 if (NumOuterTemplateParamLists > 0)
1062 NewClass->setTemplateParameterListsInfo(Context,
1063 NumOuterTemplateParamLists,
1064 OuterTemplateParamLists);
1066 // Add alignment attributes if necessary; these attributes are checked when
1067 // the ASTContext lays out the structure.
1068 if (TUK == TUK_Definition) {
1069 AddAlignmentAttributesForRecord(NewClass);
1070 AddMsStructLayoutForRecord(NewClass);
1073 ClassTemplateDecl *NewTemplate
1074 = ClassTemplateDecl::Create(Context, SemanticContext, NameLoc,
1075 DeclarationName(Name), TemplateParams,
1076 NewClass, PrevClassTemplate);
1077 NewClass->setDescribedClassTemplate(NewTemplate);
1079 if (ModulePrivateLoc.isValid())
1080 NewTemplate->setModulePrivate();
1082 // Build the type for the class template declaration now.
1083 QualType T = NewTemplate->getInjectedClassNameSpecialization();
1084 T = Context.getInjectedClassNameType(NewClass, T);
1085 assert(T->isDependentType() && "Class template type is not dependent?");
1088 // If we are providing an explicit specialization of a member that is a
1089 // class template, make a note of that.
1090 if (PrevClassTemplate &&
1091 PrevClassTemplate->getInstantiatedFromMemberTemplate())
1092 PrevClassTemplate->setMemberSpecialization();
1094 // Set the access specifier.
1095 if (!Invalid && TUK != TUK_Friend && NewTemplate->getDeclContext()->isRecord())
1096 SetMemberAccessSpecifier(NewTemplate, PrevClassTemplate, AS);
1098 // Set the lexical context of these templates
1099 NewClass->setLexicalDeclContext(CurContext);
1100 NewTemplate->setLexicalDeclContext(CurContext);
1102 if (TUK == TUK_Definition)
1103 NewClass->startDefinition();
1106 ProcessDeclAttributeList(S, NewClass, Attr);
1108 if (PrevClassTemplate)
1109 mergeDeclAttributes(NewClass, PrevClassTemplate->getTemplatedDecl());
1111 AddPushedVisibilityAttribute(NewClass);
1113 if (TUK != TUK_Friend)
1114 PushOnScopeChains(NewTemplate, S);
1116 if (PrevClassTemplate && PrevClassTemplate->getAccess() != AS_none) {
1117 NewTemplate->setAccess(PrevClassTemplate->getAccess());
1118 NewClass->setAccess(PrevClassTemplate->getAccess());
1121 NewTemplate->setObjectOfFriendDecl(/* PreviouslyDeclared = */
1122 PrevClassTemplate != NULL);
1124 // Friend templates are visible in fairly strange ways.
1125 if (!CurContext->isDependentContext()) {
1126 DeclContext *DC = SemanticContext->getRedeclContext();
1127 DC->makeDeclVisibleInContext(NewTemplate);
1128 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC))
1129 PushOnScopeChains(NewTemplate, EnclosingScope,
1130 /* AddToContext = */ false);
1133 FriendDecl *Friend = FriendDecl::Create(Context, CurContext,
1134 NewClass->getLocation(),
1136 /*FIXME:*/NewClass->getLocation());
1137 Friend->setAccess(AS_public);
1138 CurContext->addDecl(Friend);
1142 NewTemplate->setInvalidDecl();
1143 NewClass->setInvalidDecl();
1146 ActOnDocumentableDecl(NewTemplate);
1151 /// \brief Diagnose the presence of a default template argument on a
1152 /// template parameter, which is ill-formed in certain contexts.
1154 /// \returns true if the default template argument should be dropped.
1155 static bool DiagnoseDefaultTemplateArgument(Sema &S,
1156 Sema::TemplateParamListContext TPC,
1157 SourceLocation ParamLoc,
1158 SourceRange DefArgRange) {
1160 case Sema::TPC_ClassTemplate:
1161 case Sema::TPC_TypeAliasTemplate:
1164 case Sema::TPC_FunctionTemplate:
1165 case Sema::TPC_FriendFunctionTemplateDefinition:
1166 // C++ [temp.param]p9:
1167 // A default template-argument shall not be specified in a
1168 // function template declaration or a function template
1170 // If a friend function template declaration specifies a default
1171 // template-argument, that declaration shall be a definition and shall be
1172 // the only declaration of the function template in the translation unit.
1173 // (C++98/03 doesn't have this wording; see DR226).
1174 S.Diag(ParamLoc, S.getLangOpts().CPlusPlus11 ?
1175 diag::warn_cxx98_compat_template_parameter_default_in_function_template
1176 : diag::ext_template_parameter_default_in_function_template)
1180 case Sema::TPC_ClassTemplateMember:
1181 // C++0x [temp.param]p9:
1182 // A default template-argument shall not be specified in the
1183 // template-parameter-lists of the definition of a member of a
1184 // class template that appears outside of the member's class.
1185 S.Diag(ParamLoc, diag::err_template_parameter_default_template_member)
1189 case Sema::TPC_FriendFunctionTemplate:
1190 // C++ [temp.param]p9:
1191 // A default template-argument shall not be specified in a
1192 // friend template declaration.
1193 S.Diag(ParamLoc, diag::err_template_parameter_default_friend_template)
1197 // FIXME: C++0x [temp.param]p9 allows default template-arguments
1198 // for friend function templates if there is only a single
1199 // declaration (and it is a definition). Strange!
1202 llvm_unreachable("Invalid TemplateParamListContext!");
1205 /// \brief Check for unexpanded parameter packs within the template parameters
1206 /// of a template template parameter, recursively.
1207 static bool DiagnoseUnexpandedParameterPacks(Sema &S,
1208 TemplateTemplateParmDecl *TTP) {
1209 // A template template parameter which is a parameter pack is also a pack
1211 if (TTP->isParameterPack())
1214 TemplateParameterList *Params = TTP->getTemplateParameters();
1215 for (unsigned I = 0, N = Params->size(); I != N; ++I) {
1216 NamedDecl *P = Params->getParam(I);
1217 if (NonTypeTemplateParmDecl *NTTP = dyn_cast<NonTypeTemplateParmDecl>(P)) {
1218 if (!NTTP->isParameterPack() &&
1219 S.DiagnoseUnexpandedParameterPack(NTTP->getLocation(),
1220 NTTP->getTypeSourceInfo(),
1221 Sema::UPPC_NonTypeTemplateParameterType))
1227 if (TemplateTemplateParmDecl *InnerTTP
1228 = dyn_cast<TemplateTemplateParmDecl>(P))
1229 if (DiagnoseUnexpandedParameterPacks(S, InnerTTP))
1236 /// \brief Checks the validity of a template parameter list, possibly
1237 /// considering the template parameter list from a previous
1240 /// If an "old" template parameter list is provided, it must be
1241 /// equivalent (per TemplateParameterListsAreEqual) to the "new"
1242 /// template parameter list.
1244 /// \param NewParams Template parameter list for a new template
1245 /// declaration. This template parameter list will be updated with any
1246 /// default arguments that are carried through from the previous
1247 /// template parameter list.
1249 /// \param OldParams If provided, template parameter list from a
1250 /// previous declaration of the same template. Default template
1251 /// arguments will be merged from the old template parameter list to
1252 /// the new template parameter list.
1254 /// \param TPC Describes the context in which we are checking the given
1255 /// template parameter list.
1257 /// \returns true if an error occurred, false otherwise.
1258 bool Sema::CheckTemplateParameterList(TemplateParameterList *NewParams,
1259 TemplateParameterList *OldParams,
1260 TemplateParamListContext TPC) {
1261 bool Invalid = false;
1263 // C++ [temp.param]p10:
1264 // The set of default template-arguments available for use with a
1265 // template declaration or definition is obtained by merging the
1266 // default arguments from the definition (if in scope) and all
1267 // declarations in scope in the same way default function
1268 // arguments are (8.3.6).
1269 bool SawDefaultArgument = false;
1270 SourceLocation PreviousDefaultArgLoc;
1272 // Dummy initialization to avoid warnings.
1273 TemplateParameterList::iterator OldParam = NewParams->end();
1275 OldParam = OldParams->begin();
1277 bool RemoveDefaultArguments = false;
1278 for (TemplateParameterList::iterator NewParam = NewParams->begin(),
1279 NewParamEnd = NewParams->end();
1280 NewParam != NewParamEnd; ++NewParam) {
1281 // Variables used to diagnose redundant default arguments
1282 bool RedundantDefaultArg = false;
1283 SourceLocation OldDefaultLoc;
1284 SourceLocation NewDefaultLoc;
1286 // Variable used to diagnose missing default arguments
1287 bool MissingDefaultArg = false;
1289 // Variable used to diagnose non-final parameter packs
1290 bool SawParameterPack = false;
1292 if (TemplateTypeParmDecl *NewTypeParm
1293 = dyn_cast<TemplateTypeParmDecl>(*NewParam)) {
1294 // Check the presence of a default argument here.
1295 if (NewTypeParm->hasDefaultArgument() &&
1296 DiagnoseDefaultTemplateArgument(*this, TPC,
1297 NewTypeParm->getLocation(),
1298 NewTypeParm->getDefaultArgumentInfo()->getTypeLoc()
1300 NewTypeParm->removeDefaultArgument();
1302 // Merge default arguments for template type parameters.
1303 TemplateTypeParmDecl *OldTypeParm
1304 = OldParams? cast<TemplateTypeParmDecl>(*OldParam) : 0;
1306 if (NewTypeParm->isParameterPack()) {
1307 assert(!NewTypeParm->hasDefaultArgument() &&
1308 "Parameter packs can't have a default argument!");
1309 SawParameterPack = true;
1310 } else if (OldTypeParm && OldTypeParm->hasDefaultArgument() &&
1311 NewTypeParm->hasDefaultArgument()) {
1312 OldDefaultLoc = OldTypeParm->getDefaultArgumentLoc();
1313 NewDefaultLoc = NewTypeParm->getDefaultArgumentLoc();
1314 SawDefaultArgument = true;
1315 RedundantDefaultArg = true;
1316 PreviousDefaultArgLoc = NewDefaultLoc;
1317 } else if (OldTypeParm && OldTypeParm->hasDefaultArgument()) {
1318 // Merge the default argument from the old declaration to the
1320 SawDefaultArgument = true;
1321 NewTypeParm->setDefaultArgument(OldTypeParm->getDefaultArgumentInfo(),
1323 PreviousDefaultArgLoc = OldTypeParm->getDefaultArgumentLoc();
1324 } else if (NewTypeParm->hasDefaultArgument()) {
1325 SawDefaultArgument = true;
1326 PreviousDefaultArgLoc = NewTypeParm->getDefaultArgumentLoc();
1327 } else if (SawDefaultArgument)
1328 MissingDefaultArg = true;
1329 } else if (NonTypeTemplateParmDecl *NewNonTypeParm
1330 = dyn_cast<NonTypeTemplateParmDecl>(*NewParam)) {
1331 // Check for unexpanded parameter packs.
1332 if (!NewNonTypeParm->isParameterPack() &&
1333 DiagnoseUnexpandedParameterPack(NewNonTypeParm->getLocation(),
1334 NewNonTypeParm->getTypeSourceInfo(),
1335 UPPC_NonTypeTemplateParameterType)) {
1340 // Check the presence of a default argument here.
1341 if (NewNonTypeParm->hasDefaultArgument() &&
1342 DiagnoseDefaultTemplateArgument(*this, TPC,
1343 NewNonTypeParm->getLocation(),
1344 NewNonTypeParm->getDefaultArgument()->getSourceRange())) {
1345 NewNonTypeParm->removeDefaultArgument();
1348 // Merge default arguments for non-type template parameters
1349 NonTypeTemplateParmDecl *OldNonTypeParm
1350 = OldParams? cast<NonTypeTemplateParmDecl>(*OldParam) : 0;
1351 if (NewNonTypeParm->isParameterPack()) {
1352 assert(!NewNonTypeParm->hasDefaultArgument() &&
1353 "Parameter packs can't have a default argument!");
1354 if (!NewNonTypeParm->isPackExpansion())
1355 SawParameterPack = true;
1356 } else if (OldNonTypeParm && OldNonTypeParm->hasDefaultArgument() &&
1357 NewNonTypeParm->hasDefaultArgument()) {
1358 OldDefaultLoc = OldNonTypeParm->getDefaultArgumentLoc();
1359 NewDefaultLoc = NewNonTypeParm->getDefaultArgumentLoc();
1360 SawDefaultArgument = true;
1361 RedundantDefaultArg = true;
1362 PreviousDefaultArgLoc = NewDefaultLoc;
1363 } else if (OldNonTypeParm && OldNonTypeParm->hasDefaultArgument()) {
1364 // Merge the default argument from the old declaration to the
1366 SawDefaultArgument = true;
1367 // FIXME: We need to create a new kind of "default argument"
1368 // expression that points to a previous non-type template
1370 NewNonTypeParm->setDefaultArgument(
1371 OldNonTypeParm->getDefaultArgument(),
1372 /*Inherited=*/ true);
1373 PreviousDefaultArgLoc = OldNonTypeParm->getDefaultArgumentLoc();
1374 } else if (NewNonTypeParm->hasDefaultArgument()) {
1375 SawDefaultArgument = true;
1376 PreviousDefaultArgLoc = NewNonTypeParm->getDefaultArgumentLoc();
1377 } else if (SawDefaultArgument)
1378 MissingDefaultArg = true;
1380 TemplateTemplateParmDecl *NewTemplateParm
1381 = cast<TemplateTemplateParmDecl>(*NewParam);
1383 // Check for unexpanded parameter packs, recursively.
1384 if (::DiagnoseUnexpandedParameterPacks(*this, NewTemplateParm)) {
1389 // Check the presence of a default argument here.
1390 if (NewTemplateParm->hasDefaultArgument() &&
1391 DiagnoseDefaultTemplateArgument(*this, TPC,
1392 NewTemplateParm->getLocation(),
1393 NewTemplateParm->getDefaultArgument().getSourceRange()))
1394 NewTemplateParm->removeDefaultArgument();
1396 // Merge default arguments for template template parameters
1397 TemplateTemplateParmDecl *OldTemplateParm
1398 = OldParams? cast<TemplateTemplateParmDecl>(*OldParam) : 0;
1399 if (NewTemplateParm->isParameterPack()) {
1400 assert(!NewTemplateParm->hasDefaultArgument() &&
1401 "Parameter packs can't have a default argument!");
1402 if (!NewTemplateParm->isPackExpansion())
1403 SawParameterPack = true;
1404 } else if (OldTemplateParm && OldTemplateParm->hasDefaultArgument() &&
1405 NewTemplateParm->hasDefaultArgument()) {
1406 OldDefaultLoc = OldTemplateParm->getDefaultArgument().getLocation();
1407 NewDefaultLoc = NewTemplateParm->getDefaultArgument().getLocation();
1408 SawDefaultArgument = true;
1409 RedundantDefaultArg = true;
1410 PreviousDefaultArgLoc = NewDefaultLoc;
1411 } else if (OldTemplateParm && OldTemplateParm->hasDefaultArgument()) {
1412 // Merge the default argument from the old declaration to the
1414 SawDefaultArgument = true;
1415 // FIXME: We need to create a new kind of "default argument" expression
1416 // that points to a previous template template parameter.
1417 NewTemplateParm->setDefaultArgument(
1418 OldTemplateParm->getDefaultArgument(),
1419 /*Inherited=*/ true);
1420 PreviousDefaultArgLoc
1421 = OldTemplateParm->getDefaultArgument().getLocation();
1422 } else if (NewTemplateParm->hasDefaultArgument()) {
1423 SawDefaultArgument = true;
1424 PreviousDefaultArgLoc
1425 = NewTemplateParm->getDefaultArgument().getLocation();
1426 } else if (SawDefaultArgument)
1427 MissingDefaultArg = true;
1430 // C++11 [temp.param]p11:
1431 // If a template parameter of a primary class template or alias template
1432 // is a template parameter pack, it shall be the last template parameter.
1433 if (SawParameterPack && (NewParam + 1) != NewParamEnd &&
1434 (TPC == TPC_ClassTemplate || TPC == TPC_TypeAliasTemplate)) {
1435 Diag((*NewParam)->getLocation(),
1436 diag::err_template_param_pack_must_be_last_template_parameter);
1440 if (RedundantDefaultArg) {
1441 // C++ [temp.param]p12:
1442 // A template-parameter shall not be given default arguments
1443 // by two different declarations in the same scope.
1444 Diag(NewDefaultLoc, diag::err_template_param_default_arg_redefinition);
1445 Diag(OldDefaultLoc, diag::note_template_param_prev_default_arg);
1447 } else if (MissingDefaultArg && TPC != TPC_FunctionTemplate) {
1448 // C++ [temp.param]p11:
1449 // If a template-parameter of a class template has a default
1450 // template-argument, each subsequent template-parameter shall either
1451 // have a default template-argument supplied or be a template parameter
1453 Diag((*NewParam)->getLocation(),
1454 diag::err_template_param_default_arg_missing);
1455 Diag(PreviousDefaultArgLoc, diag::note_template_param_prev_default_arg);
1457 RemoveDefaultArguments = true;
1460 // If we have an old template parameter list that we're merging
1461 // in, move on to the next parameter.
1466 // We were missing some default arguments at the end of the list, so remove
1467 // all of the default arguments.
1468 if (RemoveDefaultArguments) {
1469 for (TemplateParameterList::iterator NewParam = NewParams->begin(),
1470 NewParamEnd = NewParams->end();
1471 NewParam != NewParamEnd; ++NewParam) {
1472 if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(*NewParam))
1473 TTP->removeDefaultArgument();
1474 else if (NonTypeTemplateParmDecl *NTTP
1475 = dyn_cast<NonTypeTemplateParmDecl>(*NewParam))
1476 NTTP->removeDefaultArgument();
1478 cast<TemplateTemplateParmDecl>(*NewParam)->removeDefaultArgument();
1487 /// A class which looks for a use of a certain level of template
1489 struct DependencyChecker : RecursiveASTVisitor<DependencyChecker> {
1490 typedef RecursiveASTVisitor<DependencyChecker> super;
1495 DependencyChecker(TemplateParameterList *Params) : Match(false) {
1496 NamedDecl *ND = Params->getParam(0);
1497 if (TemplateTypeParmDecl *PD = dyn_cast<TemplateTypeParmDecl>(ND)) {
1498 Depth = PD->getDepth();
1499 } else if (NonTypeTemplateParmDecl *PD =
1500 dyn_cast<NonTypeTemplateParmDecl>(ND)) {
1501 Depth = PD->getDepth();
1503 Depth = cast<TemplateTemplateParmDecl>(ND)->getDepth();
1507 bool Matches(unsigned ParmDepth) {
1508 if (ParmDepth >= Depth) {
1515 bool VisitTemplateTypeParmType(const TemplateTypeParmType *T) {
1516 return !Matches(T->getDepth());
1519 bool TraverseTemplateName(TemplateName N) {
1520 if (TemplateTemplateParmDecl *PD =
1521 dyn_cast_or_null<TemplateTemplateParmDecl>(N.getAsTemplateDecl()))
1522 if (Matches(PD->getDepth())) return false;
1523 return super::TraverseTemplateName(N);
1526 bool VisitDeclRefExpr(DeclRefExpr *E) {
1527 if (NonTypeTemplateParmDecl *PD =
1528 dyn_cast<NonTypeTemplateParmDecl>(E->getDecl())) {
1529 if (PD->getDepth() == Depth) {
1534 return super::VisitDeclRefExpr(E);
1537 bool TraverseInjectedClassNameType(const InjectedClassNameType *T) {
1538 return TraverseType(T->getInjectedSpecializationType());
1543 /// Determines whether a given type depends on the given parameter
1546 DependsOnTemplateParameters(QualType T, TemplateParameterList *Params) {
1547 DependencyChecker Checker(Params);
1548 Checker.TraverseType(T);
1549 return Checker.Match;
1552 // Find the source range corresponding to the named type in the given
1553 // nested-name-specifier, if any.
1554 static SourceRange getRangeOfTypeInNestedNameSpecifier(ASTContext &Context,
1556 const CXXScopeSpec &SS) {
1557 NestedNameSpecifierLoc NNSLoc(SS.getScopeRep(), SS.location_data());
1558 while (NestedNameSpecifier *NNS = NNSLoc.getNestedNameSpecifier()) {
1559 if (const Type *CurType = NNS->getAsType()) {
1560 if (Context.hasSameUnqualifiedType(T, QualType(CurType, 0)))
1561 return NNSLoc.getTypeLoc().getSourceRange();
1565 NNSLoc = NNSLoc.getPrefix();
1568 return SourceRange();
1571 /// \brief Match the given template parameter lists to the given scope
1572 /// specifier, returning the template parameter list that applies to the
1575 /// \param DeclStartLoc the start of the declaration that has a scope
1576 /// specifier or a template parameter list.
1578 /// \param DeclLoc The location of the declaration itself.
1580 /// \param SS the scope specifier that will be matched to the given template
1581 /// parameter lists. This scope specifier precedes a qualified name that is
1584 /// \param ParamLists the template parameter lists, from the outermost to the
1585 /// innermost template parameter lists.
1587 /// \param NumParamLists the number of template parameter lists in ParamLists.
1589 /// \param IsFriend Whether to apply the slightly different rules for
1590 /// matching template parameters to scope specifiers in friend
1593 /// \param IsExplicitSpecialization will be set true if the entity being
1594 /// declared is an explicit specialization, false otherwise.
1596 /// \returns the template parameter list, if any, that corresponds to the
1597 /// name that is preceded by the scope specifier @p SS. This template
1598 /// parameter list may have template parameters (if we're declaring a
1599 /// template) or may have no template parameters (if we're declaring a
1600 /// template specialization), or may be NULL (if what we're declaring isn't
1601 /// itself a template).
1602 TemplateParameterList *
1603 Sema::MatchTemplateParametersToScopeSpecifier(SourceLocation DeclStartLoc,
1604 SourceLocation DeclLoc,
1605 const CXXScopeSpec &SS,
1606 TemplateParameterList **ParamLists,
1607 unsigned NumParamLists,
1609 bool &IsExplicitSpecialization,
1611 IsExplicitSpecialization = false;
1614 // The sequence of nested types to which we will match up the template
1615 // parameter lists. We first build this list by starting with the type named
1616 // by the nested-name-specifier and walking out until we run out of types.
1617 SmallVector<QualType, 4> NestedTypes;
1619 if (SS.getScopeRep()) {
1620 if (CXXRecordDecl *Record
1621 = dyn_cast_or_null<CXXRecordDecl>(computeDeclContext(SS, true)))
1622 T = Context.getTypeDeclType(Record);
1624 T = QualType(SS.getScopeRep()->getAsType(), 0);
1627 // If we found an explicit specialization that prevents us from needing
1628 // 'template<>' headers, this will be set to the location of that
1629 // explicit specialization.
1630 SourceLocation ExplicitSpecLoc;
1632 while (!T.isNull()) {
1633 NestedTypes.push_back(T);
1635 // Retrieve the parent of a record type.
1636 if (CXXRecordDecl *Record = T->getAsCXXRecordDecl()) {
1637 // If this type is an explicit specialization, we're done.
1638 if (ClassTemplateSpecializationDecl *Spec
1639 = dyn_cast<ClassTemplateSpecializationDecl>(Record)) {
1640 if (!isa<ClassTemplatePartialSpecializationDecl>(Spec) &&
1641 Spec->getSpecializationKind() == TSK_ExplicitSpecialization) {
1642 ExplicitSpecLoc = Spec->getLocation();
1645 } else if (Record->getTemplateSpecializationKind()
1646 == TSK_ExplicitSpecialization) {
1647 ExplicitSpecLoc = Record->getLocation();
1651 if (TypeDecl *Parent = dyn_cast<TypeDecl>(Record->getParent()))
1652 T = Context.getTypeDeclType(Parent);
1658 if (const TemplateSpecializationType *TST
1659 = T->getAs<TemplateSpecializationType>()) {
1660 if (TemplateDecl *Template = TST->getTemplateName().getAsTemplateDecl()) {
1661 if (TypeDecl *Parent = dyn_cast<TypeDecl>(Template->getDeclContext()))
1662 T = Context.getTypeDeclType(Parent);
1669 // Look one step prior in a dependent template specialization type.
1670 if (const DependentTemplateSpecializationType *DependentTST
1671 = T->getAs<DependentTemplateSpecializationType>()) {
1672 if (NestedNameSpecifier *NNS = DependentTST->getQualifier())
1673 T = QualType(NNS->getAsType(), 0);
1679 // Look one step prior in a dependent name type.
1680 if (const DependentNameType *DependentName = T->getAs<DependentNameType>()){
1681 if (NestedNameSpecifier *NNS = DependentName->getQualifier())
1682 T = QualType(NNS->getAsType(), 0);
1688 // Retrieve the parent of an enumeration type.
1689 if (const EnumType *EnumT = T->getAs<EnumType>()) {
1690 // FIXME: Forward-declared enums require a TSK_ExplicitSpecialization
1692 EnumDecl *Enum = EnumT->getDecl();
1694 // Get to the parent type.
1695 if (TypeDecl *Parent = dyn_cast<TypeDecl>(Enum->getParent()))
1696 T = Context.getTypeDeclType(Parent);
1704 // Reverse the nested types list, since we want to traverse from the outermost
1705 // to the innermost while checking template-parameter-lists.
1706 std::reverse(NestedTypes.begin(), NestedTypes.end());
1708 // C++0x [temp.expl.spec]p17:
1709 // A member or a member template may be nested within many
1710 // enclosing class templates. In an explicit specialization for
1711 // such a member, the member declaration shall be preceded by a
1712 // template<> for each enclosing class template that is
1713 // explicitly specialized.
1714 bool SawNonEmptyTemplateParameterList = false;
1715 unsigned ParamIdx = 0;
1716 for (unsigned TypeIdx = 0, NumTypes = NestedTypes.size(); TypeIdx != NumTypes;
1718 T = NestedTypes[TypeIdx];
1720 // Whether we expect a 'template<>' header.
1721 bool NeedEmptyTemplateHeader = false;
1723 // Whether we expect a template header with parameters.
1724 bool NeedNonemptyTemplateHeader = false;
1726 // For a dependent type, the set of template parameters that we
1728 TemplateParameterList *ExpectedTemplateParams = 0;
1730 // C++0x [temp.expl.spec]p15:
1731 // A member or a member template may be nested within many enclosing
1732 // class templates. In an explicit specialization for such a member, the
1733 // member declaration shall be preceded by a template<> for each
1734 // enclosing class template that is explicitly specialized.
1735 if (CXXRecordDecl *Record = T->getAsCXXRecordDecl()) {
1736 if (ClassTemplatePartialSpecializationDecl *Partial
1737 = dyn_cast<ClassTemplatePartialSpecializationDecl>(Record)) {
1738 ExpectedTemplateParams = Partial->getTemplateParameters();
1739 NeedNonemptyTemplateHeader = true;
1740 } else if (Record->isDependentType()) {
1741 if (Record->getDescribedClassTemplate()) {
1742 ExpectedTemplateParams = Record->getDescribedClassTemplate()
1743 ->getTemplateParameters();
1744 NeedNonemptyTemplateHeader = true;
1746 } else if (ClassTemplateSpecializationDecl *Spec
1747 = dyn_cast<ClassTemplateSpecializationDecl>(Record)) {
1748 // C++0x [temp.expl.spec]p4:
1749 // Members of an explicitly specialized class template are defined
1750 // in the same manner as members of normal classes, and not using
1751 // the template<> syntax.
1752 if (Spec->getSpecializationKind() != TSK_ExplicitSpecialization)
1753 NeedEmptyTemplateHeader = true;
1756 } else if (Record->getTemplateSpecializationKind()) {
1757 if (Record->getTemplateSpecializationKind()
1758 != TSK_ExplicitSpecialization &&
1759 TypeIdx == NumTypes - 1)
1760 IsExplicitSpecialization = true;
1764 } else if (const TemplateSpecializationType *TST
1765 = T->getAs<TemplateSpecializationType>()) {
1766 if (TemplateDecl *Template = TST->getTemplateName().getAsTemplateDecl()) {
1767 ExpectedTemplateParams = Template->getTemplateParameters();
1768 NeedNonemptyTemplateHeader = true;
1770 } else if (T->getAs<DependentTemplateSpecializationType>()) {
1771 // FIXME: We actually could/should check the template arguments here
1772 // against the corresponding template parameter list.
1773 NeedNonemptyTemplateHeader = false;
1776 // C++ [temp.expl.spec]p16:
1777 // In an explicit specialization declaration for a member of a class
1778 // template or a member template that ap- pears in namespace scope, the
1779 // member template and some of its enclosing class templates may remain
1780 // unspecialized, except that the declaration shall not explicitly
1781 // specialize a class member template if its en- closing class templates
1782 // are not explicitly specialized as well.
1783 if (ParamIdx < NumParamLists) {
1784 if (ParamLists[ParamIdx]->size() == 0) {
1785 if (SawNonEmptyTemplateParameterList) {
1786 Diag(DeclLoc, diag::err_specialize_member_of_template)
1787 << ParamLists[ParamIdx]->getSourceRange();
1789 IsExplicitSpecialization = false;
1793 SawNonEmptyTemplateParameterList = true;
1796 if (NeedEmptyTemplateHeader) {
1797 // If we're on the last of the types, and we need a 'template<>' header
1798 // here, then it's an explicit specialization.
1799 if (TypeIdx == NumTypes - 1)
1800 IsExplicitSpecialization = true;
1802 if (ParamIdx < NumParamLists) {
1803 if (ParamLists[ParamIdx]->size() > 0) {
1804 // The header has template parameters when it shouldn't. Complain.
1805 Diag(ParamLists[ParamIdx]->getTemplateLoc(),
1806 diag::err_template_param_list_matches_nontemplate)
1808 << SourceRange(ParamLists[ParamIdx]->getLAngleLoc(),
1809 ParamLists[ParamIdx]->getRAngleLoc())
1810 << getRangeOfTypeInNestedNameSpecifier(Context, T, SS);
1815 // Consume this template header.
1821 // We don't have a template header, but we should.
1822 SourceLocation ExpectedTemplateLoc;
1823 if (NumParamLists > 0)
1824 ExpectedTemplateLoc = ParamLists[0]->getTemplateLoc();
1826 ExpectedTemplateLoc = DeclStartLoc;
1828 Diag(DeclLoc, diag::err_template_spec_needs_header)
1829 << getRangeOfTypeInNestedNameSpecifier(Context, T, SS)
1830 << FixItHint::CreateInsertion(ExpectedTemplateLoc, "template<> ");
1836 if (NeedNonemptyTemplateHeader) {
1837 // In friend declarations we can have template-ids which don't
1838 // depend on the corresponding template parameter lists. But
1839 // assume that empty parameter lists are supposed to match this
1841 if (IsFriend && T->isDependentType()) {
1842 if (ParamIdx < NumParamLists &&
1843 DependsOnTemplateParameters(T, ParamLists[ParamIdx]))
1844 ExpectedTemplateParams = 0;
1849 if (ParamIdx < NumParamLists) {
1850 // Check the template parameter list, if we can.
1851 if (ExpectedTemplateParams &&
1852 !TemplateParameterListsAreEqual(ParamLists[ParamIdx],
1853 ExpectedTemplateParams,
1854 true, TPL_TemplateMatch))
1858 CheckTemplateParameterList(ParamLists[ParamIdx], 0,
1859 TPC_ClassTemplateMember))
1866 Diag(DeclLoc, diag::err_template_spec_needs_template_parameters)
1868 << getRangeOfTypeInNestedNameSpecifier(Context, T, SS);
1874 // If there were at least as many template-ids as there were template
1875 // parameter lists, then there are no template parameter lists remaining for
1876 // the declaration itself.
1877 if (ParamIdx >= NumParamLists)
1880 // If there were too many template parameter lists, complain about that now.
1881 if (ParamIdx < NumParamLists - 1) {
1882 bool HasAnyExplicitSpecHeader = false;
1883 bool AllExplicitSpecHeaders = true;
1884 for (unsigned I = ParamIdx; I != NumParamLists - 1; ++I) {
1885 if (ParamLists[I]->size() == 0)
1886 HasAnyExplicitSpecHeader = true;
1888 AllExplicitSpecHeaders = false;
1891 Diag(ParamLists[ParamIdx]->getTemplateLoc(),
1892 AllExplicitSpecHeaders? diag::warn_template_spec_extra_headers
1893 : diag::err_template_spec_extra_headers)
1894 << SourceRange(ParamLists[ParamIdx]->getTemplateLoc(),
1895 ParamLists[NumParamLists - 2]->getRAngleLoc());
1897 // If there was a specialization somewhere, such that 'template<>' is
1898 // not required, and there were any 'template<>' headers, note where the
1899 // specialization occurred.
1900 if (ExplicitSpecLoc.isValid() && HasAnyExplicitSpecHeader)
1901 Diag(ExplicitSpecLoc,
1902 diag::note_explicit_template_spec_does_not_need_header)
1903 << NestedTypes.back();
1905 // We have a template parameter list with no corresponding scope, which
1906 // means that the resulting template declaration can't be instantiated
1907 // properly (we'll end up with dependent nodes when we shouldn't).
1908 if (!AllExplicitSpecHeaders)
1912 // C++ [temp.expl.spec]p16:
1913 // In an explicit specialization declaration for a member of a class
1914 // template or a member template that ap- pears in namespace scope, the
1915 // member template and some of its enclosing class templates may remain
1916 // unspecialized, except that the declaration shall not explicitly
1917 // specialize a class member template if its en- closing class templates
1918 // are not explicitly specialized as well.
1919 if (ParamLists[NumParamLists - 1]->size() == 0 &&
1920 SawNonEmptyTemplateParameterList) {
1921 Diag(DeclLoc, diag::err_specialize_member_of_template)
1922 << ParamLists[ParamIdx]->getSourceRange();
1924 IsExplicitSpecialization = false;
1928 // Return the last template parameter list, which corresponds to the
1929 // entity being declared.
1930 return ParamLists[NumParamLists - 1];
1933 void Sema::NoteAllFoundTemplates(TemplateName Name) {
1934 if (TemplateDecl *Template = Name.getAsTemplateDecl()) {
1935 Diag(Template->getLocation(), diag::note_template_declared_here)
1936 << (isa<FunctionTemplateDecl>(Template)? 0
1937 : isa<ClassTemplateDecl>(Template)? 1
1938 : isa<TypeAliasTemplateDecl>(Template)? 2
1940 << Template->getDeclName();
1944 if (OverloadedTemplateStorage *OST = Name.getAsOverloadedTemplate()) {
1945 for (OverloadedTemplateStorage::iterator I = OST->begin(),
1948 Diag((*I)->getLocation(), diag::note_template_declared_here)
1949 << 0 << (*I)->getDeclName();
1955 QualType Sema::CheckTemplateIdType(TemplateName Name,
1956 SourceLocation TemplateLoc,
1957 TemplateArgumentListInfo &TemplateArgs) {
1958 DependentTemplateName *DTN
1959 = Name.getUnderlying().getAsDependentTemplateName();
1960 if (DTN && DTN->isIdentifier())
1961 // When building a template-id where the template-name is dependent,
1962 // assume the template is a type template. Either our assumption is
1963 // correct, or the code is ill-formed and will be diagnosed when the
1964 // dependent name is substituted.
1965 return Context.getDependentTemplateSpecializationType(ETK_None,
1966 DTN->getQualifier(),
1967 DTN->getIdentifier(),
1970 TemplateDecl *Template = Name.getAsTemplateDecl();
1971 if (!Template || isa<FunctionTemplateDecl>(Template)) {
1972 // We might have a substituted template template parameter pack. If so,
1973 // build a template specialization type for it.
1974 if (Name.getAsSubstTemplateTemplateParmPack())
1975 return Context.getTemplateSpecializationType(Name, TemplateArgs);
1977 Diag(TemplateLoc, diag::err_template_id_not_a_type)
1979 NoteAllFoundTemplates(Name);
1983 // Check that the template argument list is well-formed for this
1985 SmallVector<TemplateArgument, 4> Converted;
1986 bool ExpansionIntoFixedList = false;
1987 if (CheckTemplateArgumentList(Template, TemplateLoc, TemplateArgs,
1988 false, Converted, &ExpansionIntoFixedList))
1993 bool InstantiationDependent = false;
1994 TypeAliasTemplateDecl *AliasTemplate = 0;
1995 if (!ExpansionIntoFixedList &&
1996 (AliasTemplate = dyn_cast<TypeAliasTemplateDecl>(Template))) {
1997 // Find the canonical type for this type alias template specialization.
1998 TypeAliasDecl *Pattern = AliasTemplate->getTemplatedDecl();
1999 if (Pattern->isInvalidDecl())
2002 TemplateArgumentList TemplateArgs(TemplateArgumentList::OnStack,
2003 Converted.data(), Converted.size());
2005 // Only substitute for the innermost template argument list.
2006 MultiLevelTemplateArgumentList TemplateArgLists;
2007 TemplateArgLists.addOuterTemplateArguments(&TemplateArgs);
2008 unsigned Depth = AliasTemplate->getTemplateParameters()->getDepth();
2009 for (unsigned I = 0; I < Depth; ++I)
2010 TemplateArgLists.addOuterTemplateArguments(0, 0);
2012 LocalInstantiationScope Scope(*this);
2013 InstantiatingTemplate Inst(*this, TemplateLoc, Template);
2017 CanonType = SubstType(Pattern->getUnderlyingType(),
2018 TemplateArgLists, AliasTemplate->getLocation(),
2019 AliasTemplate->getDeclName());
2020 if (CanonType.isNull())
2022 } else if (Name.isDependent() ||
2023 TemplateSpecializationType::anyDependentTemplateArguments(
2024 TemplateArgs, InstantiationDependent)) {
2025 // This class template specialization is a dependent
2026 // type. Therefore, its canonical type is another class template
2027 // specialization type that contains all of the converted
2028 // arguments in canonical form. This ensures that, e.g., A<T> and
2029 // A<T, T> have identical types when A is declared as:
2031 // template<typename T, typename U = T> struct A;
2032 TemplateName CanonName = Context.getCanonicalTemplateName(Name);
2033 CanonType = Context.getTemplateSpecializationType(CanonName,
2037 // FIXME: CanonType is not actually the canonical type, and unfortunately
2038 // it is a TemplateSpecializationType that we will never use again.
2039 // In the future, we need to teach getTemplateSpecializationType to only
2040 // build the canonical type and return that to us.
2041 CanonType = Context.getCanonicalType(CanonType);
2043 // This might work out to be a current instantiation, in which
2044 // case the canonical type needs to be the InjectedClassNameType.
2046 // TODO: in theory this could be a simple hashtable lookup; most
2047 // changes to CurContext don't change the set of current
2049 if (isa<ClassTemplateDecl>(Template)) {
2050 for (DeclContext *Ctx = CurContext; Ctx; Ctx = Ctx->getLookupParent()) {
2051 // If we get out to a namespace, we're done.
2052 if (Ctx->isFileContext()) break;
2054 // If this isn't a record, keep looking.
2055 CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Ctx);
2056 if (!Record) continue;
2058 // Look for one of the two cases with InjectedClassNameTypes
2059 // and check whether it's the same template.
2060 if (!isa<ClassTemplatePartialSpecializationDecl>(Record) &&
2061 !Record->getDescribedClassTemplate())
2064 // Fetch the injected class name type and check whether its
2065 // injected type is equal to the type we just built.
2066 QualType ICNT = Context.getTypeDeclType(Record);
2067 QualType Injected = cast<InjectedClassNameType>(ICNT)
2068 ->getInjectedSpecializationType();
2070 if (CanonType != Injected->getCanonicalTypeInternal())
2073 // If so, the canonical type of this TST is the injected
2074 // class name type of the record we just found.
2075 assert(ICNT.isCanonical());
2080 } else if (ClassTemplateDecl *ClassTemplate
2081 = dyn_cast<ClassTemplateDecl>(Template)) {
2082 // Find the class template specialization declaration that
2083 // corresponds to these arguments.
2084 void *InsertPos = 0;
2085 ClassTemplateSpecializationDecl *Decl
2086 = ClassTemplate->findSpecialization(Converted.data(), Converted.size(),
2089 // This is the first time we have referenced this class template
2090 // specialization. Create the canonical declaration and add it to
2091 // the set of specializations.
2092 Decl = ClassTemplateSpecializationDecl::Create(Context,
2093 ClassTemplate->getTemplatedDecl()->getTagKind(),
2094 ClassTemplate->getDeclContext(),
2095 ClassTemplate->getTemplatedDecl()->getLocStart(),
2096 ClassTemplate->getLocation(),
2099 Converted.size(), 0);
2100 ClassTemplate->AddSpecialization(Decl, InsertPos);
2101 if (ClassTemplate->isOutOfLine())
2102 Decl->setLexicalDeclContext(ClassTemplate->getLexicalDeclContext());
2105 CanonType = Context.getTypeDeclType(Decl);
2106 assert(isa<RecordType>(CanonType) &&
2107 "type of non-dependent specialization is not a RecordType");
2110 // Build the fully-sugared type for this class template
2111 // specialization, which refers back to the class template
2112 // specialization we created or found.
2113 return Context.getTemplateSpecializationType(Name, TemplateArgs, CanonType);
2117 Sema::ActOnTemplateIdType(CXXScopeSpec &SS, SourceLocation TemplateKWLoc,
2118 TemplateTy TemplateD, SourceLocation TemplateLoc,
2119 SourceLocation LAngleLoc,
2120 ASTTemplateArgsPtr TemplateArgsIn,
2121 SourceLocation RAngleLoc,
2122 bool IsCtorOrDtorName) {
2126 TemplateName Template = TemplateD.getAsVal<TemplateName>();
2128 // Translate the parser's template argument list in our AST format.
2129 TemplateArgumentListInfo TemplateArgs(LAngleLoc, RAngleLoc);
2130 translateTemplateArguments(TemplateArgsIn, TemplateArgs);
2132 if (DependentTemplateName *DTN = Template.getAsDependentTemplateName()) {
2134 = Context.getDependentTemplateSpecializationType(ETK_None,
2135 DTN->getQualifier(),
2136 DTN->getIdentifier(),
2138 // Build type-source information.
2140 DependentTemplateSpecializationTypeLoc SpecTL
2141 = TLB.push<DependentTemplateSpecializationTypeLoc>(T);
2142 SpecTL.setElaboratedKeywordLoc(SourceLocation());
2143 SpecTL.setQualifierLoc(SS.getWithLocInContext(Context));
2144 SpecTL.setTemplateKeywordLoc(TemplateKWLoc);
2145 SpecTL.setTemplateNameLoc(TemplateLoc);
2146 SpecTL.setLAngleLoc(LAngleLoc);
2147 SpecTL.setRAngleLoc(RAngleLoc);
2148 for (unsigned I = 0, N = SpecTL.getNumArgs(); I != N; ++I)
2149 SpecTL.setArgLocInfo(I, TemplateArgs[I].getLocInfo());
2150 return CreateParsedType(T, TLB.getTypeSourceInfo(Context, T));
2153 QualType Result = CheckTemplateIdType(Template, TemplateLoc, TemplateArgs);
2155 if (Result.isNull())
2158 // Build type-source information.
2160 TemplateSpecializationTypeLoc SpecTL
2161 = TLB.push<TemplateSpecializationTypeLoc>(Result);
2162 SpecTL.setTemplateKeywordLoc(TemplateKWLoc);
2163 SpecTL.setTemplateNameLoc(TemplateLoc);
2164 SpecTL.setLAngleLoc(LAngleLoc);
2165 SpecTL.setRAngleLoc(RAngleLoc);
2166 for (unsigned i = 0, e = SpecTL.getNumArgs(); i != e; ++i)
2167 SpecTL.setArgLocInfo(i, TemplateArgs[i].getLocInfo());
2169 // NOTE: avoid constructing an ElaboratedTypeLoc if this is a
2170 // constructor or destructor name (in such a case, the scope specifier
2171 // will be attached to the enclosing Decl or Expr node).
2172 if (SS.isNotEmpty() && !IsCtorOrDtorName) {
2173 // Create an elaborated-type-specifier containing the nested-name-specifier.
2174 Result = Context.getElaboratedType(ETK_None, SS.getScopeRep(), Result);
2175 ElaboratedTypeLoc ElabTL = TLB.push<ElaboratedTypeLoc>(Result);
2176 ElabTL.setElaboratedKeywordLoc(SourceLocation());
2177 ElabTL.setQualifierLoc(SS.getWithLocInContext(Context));
2180 return CreateParsedType(Result, TLB.getTypeSourceInfo(Context, Result));
2183 TypeResult Sema::ActOnTagTemplateIdType(TagUseKind TUK,
2184 TypeSpecifierType TagSpec,
2185 SourceLocation TagLoc,
2187 SourceLocation TemplateKWLoc,
2188 TemplateTy TemplateD,
2189 SourceLocation TemplateLoc,
2190 SourceLocation LAngleLoc,
2191 ASTTemplateArgsPtr TemplateArgsIn,
2192 SourceLocation RAngleLoc) {
2193 TemplateName Template = TemplateD.getAsVal<TemplateName>();
2195 // Translate the parser's template argument list in our AST format.
2196 TemplateArgumentListInfo TemplateArgs(LAngleLoc, RAngleLoc);
2197 translateTemplateArguments(TemplateArgsIn, TemplateArgs);
2199 // Determine the tag kind
2200 TagTypeKind TagKind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec);
2201 ElaboratedTypeKeyword Keyword
2202 = TypeWithKeyword::getKeywordForTagTypeKind(TagKind);
2204 if (DependentTemplateName *DTN = Template.getAsDependentTemplateName()) {
2205 QualType T = Context.getDependentTemplateSpecializationType(Keyword,
2206 DTN->getQualifier(),
2207 DTN->getIdentifier(),
2210 // Build type-source information.
2212 DependentTemplateSpecializationTypeLoc SpecTL
2213 = TLB.push<DependentTemplateSpecializationTypeLoc>(T);
2214 SpecTL.setElaboratedKeywordLoc(TagLoc);
2215 SpecTL.setQualifierLoc(SS.getWithLocInContext(Context));
2216 SpecTL.setTemplateKeywordLoc(TemplateKWLoc);
2217 SpecTL.setTemplateNameLoc(TemplateLoc);
2218 SpecTL.setLAngleLoc(LAngleLoc);
2219 SpecTL.setRAngleLoc(RAngleLoc);
2220 for (unsigned I = 0, N = SpecTL.getNumArgs(); I != N; ++I)
2221 SpecTL.setArgLocInfo(I, TemplateArgs[I].getLocInfo());
2222 return CreateParsedType(T, TLB.getTypeSourceInfo(Context, T));
2225 if (TypeAliasTemplateDecl *TAT =
2226 dyn_cast_or_null<TypeAliasTemplateDecl>(Template.getAsTemplateDecl())) {
2227 // C++0x [dcl.type.elab]p2:
2228 // If the identifier resolves to a typedef-name or the simple-template-id
2229 // resolves to an alias template specialization, the
2230 // elaborated-type-specifier is ill-formed.
2231 Diag(TemplateLoc, diag::err_tag_reference_non_tag) << 4;
2232 Diag(TAT->getLocation(), diag::note_declared_at);
2235 QualType Result = CheckTemplateIdType(Template, TemplateLoc, TemplateArgs);
2236 if (Result.isNull())
2237 return TypeResult(true);
2239 // Check the tag kind
2240 if (const RecordType *RT = Result->getAs<RecordType>()) {
2241 RecordDecl *D = RT->getDecl();
2243 IdentifierInfo *Id = D->getIdentifier();
2244 assert(Id && "templated class must have an identifier");
2246 if (!isAcceptableTagRedeclaration(D, TagKind, TUK == TUK_Definition,
2248 Diag(TagLoc, diag::err_use_with_wrong_tag)
2250 << FixItHint::CreateReplacement(SourceRange(TagLoc), D->getKindName());
2251 Diag(D->getLocation(), diag::note_previous_use);
2255 // Provide source-location information for the template specialization.
2257 TemplateSpecializationTypeLoc SpecTL
2258 = TLB.push<TemplateSpecializationTypeLoc>(Result);
2259 SpecTL.setTemplateKeywordLoc(TemplateKWLoc);
2260 SpecTL.setTemplateNameLoc(TemplateLoc);
2261 SpecTL.setLAngleLoc(LAngleLoc);
2262 SpecTL.setRAngleLoc(RAngleLoc);
2263 for (unsigned i = 0, e = SpecTL.getNumArgs(); i != e; ++i)
2264 SpecTL.setArgLocInfo(i, TemplateArgs[i].getLocInfo());
2266 // Construct an elaborated type containing the nested-name-specifier (if any)
2268 Result = Context.getElaboratedType(Keyword, SS.getScopeRep(), Result);
2269 ElaboratedTypeLoc ElabTL = TLB.push<ElaboratedTypeLoc>(Result);
2270 ElabTL.setElaboratedKeywordLoc(TagLoc);
2271 ElabTL.setQualifierLoc(SS.getWithLocInContext(Context));
2272 return CreateParsedType(Result, TLB.getTypeSourceInfo(Context, Result));
2275 ExprResult Sema::BuildTemplateIdExpr(const CXXScopeSpec &SS,
2276 SourceLocation TemplateKWLoc,
2279 const TemplateArgumentListInfo *TemplateArgs) {
2280 // FIXME: Can we do any checking at this point? I guess we could check the
2281 // template arguments that we have against the template name, if the template
2282 // name refers to a single template. That's not a terribly common case,
2284 // foo<int> could identify a single function unambiguously
2285 // This approach does NOT work, since f<int>(1);
2286 // gets resolved prior to resorting to overload resolution
2287 // i.e., template<class T> void f(double);
2288 // vs template<class T, class U> void f(U);
2290 // These should be filtered out by our callers.
2291 assert(!R.empty() && "empty lookup results when building templateid");
2292 assert(!R.isAmbiguous() && "ambiguous lookup when building templateid");
2294 // We don't want lookup warnings at this point.
2295 R.suppressDiagnostics();
2297 UnresolvedLookupExpr *ULE
2298 = UnresolvedLookupExpr::Create(Context, R.getNamingClass(),
2299 SS.getWithLocInContext(Context),
2301 R.getLookupNameInfo(),
2302 RequiresADL, TemplateArgs,
2303 R.begin(), R.end());
2308 // We actually only call this from template instantiation.
2310 Sema::BuildQualifiedTemplateIdExpr(CXXScopeSpec &SS,
2311 SourceLocation TemplateKWLoc,
2312 const DeclarationNameInfo &NameInfo,
2313 const TemplateArgumentListInfo *TemplateArgs) {
2314 assert(TemplateArgs || TemplateKWLoc.isValid());
2316 if (!(DC = computeDeclContext(SS, false)) ||
2317 DC->isDependentContext() ||
2318 RequireCompleteDeclContext(SS, DC))
2319 return BuildDependentDeclRefExpr(SS, TemplateKWLoc, NameInfo, TemplateArgs);
2321 bool MemberOfUnknownSpecialization;
2322 LookupResult R(*this, NameInfo, LookupOrdinaryName);
2323 LookupTemplateName(R, (Scope*) 0, SS, QualType(), /*Entering*/ false,
2324 MemberOfUnknownSpecialization);
2326 if (R.isAmbiguous())
2330 Diag(NameInfo.getLoc(), diag::err_template_kw_refers_to_non_template)
2331 << NameInfo.getName() << SS.getRange();
2335 if (ClassTemplateDecl *Temp = R.getAsSingle<ClassTemplateDecl>()) {
2336 Diag(NameInfo.getLoc(), diag::err_template_kw_refers_to_class_template)
2337 << (NestedNameSpecifier*) SS.getScopeRep()
2338 << NameInfo.getName() << SS.getRange();
2339 Diag(Temp->getLocation(), diag::note_referenced_class_template);
2343 return BuildTemplateIdExpr(SS, TemplateKWLoc, R, /*ADL*/ false, TemplateArgs);
2346 /// \brief Form a dependent template name.
2348 /// This action forms a dependent template name given the template
2349 /// name and its (presumably dependent) scope specifier. For
2350 /// example, given "MetaFun::template apply", the scope specifier \p
2351 /// SS will be "MetaFun::", \p TemplateKWLoc contains the location
2352 /// of the "template" keyword, and "apply" is the \p Name.
2353 TemplateNameKind Sema::ActOnDependentTemplateName(Scope *S,
2355 SourceLocation TemplateKWLoc,
2356 UnqualifiedId &Name,
2357 ParsedType ObjectType,
2358 bool EnteringContext,
2359 TemplateTy &Result) {
2360 if (TemplateKWLoc.isValid() && S && !S->getTemplateParamParent())
2362 getLangOpts().CPlusPlus11 ?
2363 diag::warn_cxx98_compat_template_outside_of_template :
2364 diag::ext_template_outside_of_template)
2365 << FixItHint::CreateRemoval(TemplateKWLoc);
2367 DeclContext *LookupCtx = 0;
2369 LookupCtx = computeDeclContext(SS, EnteringContext);
2370 if (!LookupCtx && ObjectType)
2371 LookupCtx = computeDeclContext(ObjectType.get());
2373 // C++0x [temp.names]p5:
2374 // If a name prefixed by the keyword template is not the name of
2375 // a template, the program is ill-formed. [Note: the keyword
2376 // template may not be applied to non-template members of class
2377 // templates. -end note ] [ Note: as is the case with the
2378 // typename prefix, the template prefix is allowed in cases
2379 // where it is not strictly necessary; i.e., when the
2380 // nested-name-specifier or the expression on the left of the ->
2381 // or . is not dependent on a template-parameter, or the use
2382 // does not appear in the scope of a template. -end note]
2384 // Note: C++03 was more strict here, because it banned the use of
2385 // the "template" keyword prior to a template-name that was not a
2386 // dependent name. C++ DR468 relaxed this requirement (the
2387 // "template" keyword is now permitted). We follow the C++0x
2388 // rules, even in C++03 mode with a warning, retroactively applying the DR.
2389 bool MemberOfUnknownSpecialization;
2390 TemplateNameKind TNK = isTemplateName(S, SS, TemplateKWLoc.isValid(), Name,
2391 ObjectType, EnteringContext, Result,
2392 MemberOfUnknownSpecialization);
2393 if (TNK == TNK_Non_template && LookupCtx->isDependentContext() &&
2394 isa<CXXRecordDecl>(LookupCtx) &&
2395 (!cast<CXXRecordDecl>(LookupCtx)->hasDefinition() ||
2396 cast<CXXRecordDecl>(LookupCtx)->hasAnyDependentBases())) {
2397 // This is a dependent template. Handle it below.
2398 } else if (TNK == TNK_Non_template) {
2399 Diag(Name.getLocStart(),
2400 diag::err_template_kw_refers_to_non_template)
2401 << GetNameFromUnqualifiedId(Name).getName()
2402 << Name.getSourceRange()
2404 return TNK_Non_template;
2406 // We found something; return it.
2411 NestedNameSpecifier *Qualifier
2412 = static_cast<NestedNameSpecifier *>(SS.getScopeRep());
2414 switch (Name.getKind()) {
2415 case UnqualifiedId::IK_Identifier:
2416 Result = TemplateTy::make(Context.getDependentTemplateName(Qualifier,
2418 return TNK_Dependent_template_name;
2420 case UnqualifiedId::IK_OperatorFunctionId:
2421 Result = TemplateTy::make(Context.getDependentTemplateName(Qualifier,
2422 Name.OperatorFunctionId.Operator));
2423 return TNK_Dependent_template_name;
2425 case UnqualifiedId::IK_LiteralOperatorId:
2427 "We don't support these; Parse shouldn't have allowed propagation");
2433 Diag(Name.getLocStart(),
2434 diag::err_template_kw_refers_to_non_template)
2435 << GetNameFromUnqualifiedId(Name).getName()
2436 << Name.getSourceRange()
2438 return TNK_Non_template;
2441 bool Sema::CheckTemplateTypeArgument(TemplateTypeParmDecl *Param,
2442 const TemplateArgumentLoc &AL,
2443 SmallVectorImpl<TemplateArgument> &Converted) {
2444 const TemplateArgument &Arg = AL.getArgument();
2446 // Check template type parameter.
2447 switch(Arg.getKind()) {
2448 case TemplateArgument::Type:
2449 // C++ [temp.arg.type]p1:
2450 // A template-argument for a template-parameter which is a
2451 // type shall be a type-id.
2453 case TemplateArgument::Template: {
2454 // We have a template type parameter but the template argument
2455 // is a template without any arguments.
2456 SourceRange SR = AL.getSourceRange();
2457 TemplateName Name = Arg.getAsTemplate();
2458 Diag(SR.getBegin(), diag::err_template_missing_args)
2460 if (TemplateDecl *Decl = Name.getAsTemplateDecl())
2461 Diag(Decl->getLocation(), diag::note_template_decl_here);
2465 case TemplateArgument::Expression: {
2466 // We have a template type parameter but the template argument is an
2467 // expression; see if maybe it is missing the "typename" keyword.
2469 DeclarationNameInfo NameInfo;
2471 if (DeclRefExpr *ArgExpr = dyn_cast<DeclRefExpr>(Arg.getAsExpr())) {
2472 SS.Adopt(ArgExpr->getQualifierLoc());
2473 NameInfo = ArgExpr->getNameInfo();
2474 } else if (DependentScopeDeclRefExpr *ArgExpr =
2475 dyn_cast<DependentScopeDeclRefExpr>(Arg.getAsExpr())) {
2476 SS.Adopt(ArgExpr->getQualifierLoc());
2477 NameInfo = ArgExpr->getNameInfo();
2478 } else if (CXXDependentScopeMemberExpr *ArgExpr =
2479 dyn_cast<CXXDependentScopeMemberExpr>(Arg.getAsExpr())) {
2480 if (ArgExpr->isImplicitAccess()) {
2481 SS.Adopt(ArgExpr->getQualifierLoc());
2482 NameInfo = ArgExpr->getMemberNameInfo();
2486 if (NameInfo.getName().isIdentifier()) {
2487 LookupResult Result(*this, NameInfo, LookupOrdinaryName);
2488 LookupParsedName(Result, CurScope, &SS);
2490 if (Result.getAsSingle<TypeDecl>() ||
2491 Result.getResultKind() ==
2492 LookupResult::NotFoundInCurrentInstantiation) {
2493 // FIXME: Add a FixIt and fix up the template argument for recovery.
2494 SourceLocation Loc = AL.getSourceRange().getBegin();
2495 Diag(Loc, diag::err_template_arg_must_be_type_suggest);
2496 Diag(Param->getLocation(), diag::note_template_param_here);
2503 // We have a template type parameter but the template argument
2505 SourceRange SR = AL.getSourceRange();
2506 Diag(SR.getBegin(), diag::err_template_arg_must_be_type) << SR;
2507 Diag(Param->getLocation(), diag::note_template_param_here);
2513 if (CheckTemplateArgument(Param, AL.getTypeSourceInfo()))
2516 // Add the converted template type argument.
2517 QualType ArgType = Context.getCanonicalType(Arg.getAsType());
2520 // If an explicitly-specified template argument type is a lifetime type
2521 // with no lifetime qualifier, the __strong lifetime qualifier is inferred.
2522 if (getLangOpts().ObjCAutoRefCount &&
2523 ArgType->isObjCLifetimeType() &&
2524 !ArgType.getObjCLifetime()) {
2526 Qs.setObjCLifetime(Qualifiers::OCL_Strong);
2527 ArgType = Context.getQualifiedType(ArgType, Qs);
2530 Converted.push_back(TemplateArgument(ArgType));
2534 /// \brief Substitute template arguments into the default template argument for
2535 /// the given template type parameter.
2537 /// \param SemaRef the semantic analysis object for which we are performing
2538 /// the substitution.
2540 /// \param Template the template that we are synthesizing template arguments
2543 /// \param TemplateLoc the location of the template name that started the
2544 /// template-id we are checking.
2546 /// \param RAngleLoc the location of the right angle bracket ('>') that
2547 /// terminates the template-id.
2549 /// \param Param the template template parameter whose default we are
2550 /// substituting into.
2552 /// \param Converted the list of template arguments provided for template
2553 /// parameters that precede \p Param in the template parameter list.
2554 /// \returns the substituted template argument, or NULL if an error occurred.
2555 static TypeSourceInfo *
2556 SubstDefaultTemplateArgument(Sema &SemaRef,
2557 TemplateDecl *Template,
2558 SourceLocation TemplateLoc,
2559 SourceLocation RAngleLoc,
2560 TemplateTypeParmDecl *Param,
2561 SmallVectorImpl<TemplateArgument> &Converted) {
2562 TypeSourceInfo *ArgType = Param->getDefaultArgumentInfo();
2564 // If the argument type is dependent, instantiate it now based
2565 // on the previously-computed template arguments.
2566 if (ArgType->getType()->isDependentType()) {
2567 TemplateArgumentList TemplateArgs(TemplateArgumentList::OnStack,
2568 Converted.data(), Converted.size());
2570 MultiLevelTemplateArgumentList AllTemplateArgs
2571 = SemaRef.getTemplateInstantiationArgs(Template, &TemplateArgs);
2573 Sema::InstantiatingTemplate Inst(SemaRef, TemplateLoc,
2574 Template, Converted,
2575 SourceRange(TemplateLoc, RAngleLoc));
2579 Sema::ContextRAII SavedContext(SemaRef, Template->getDeclContext());
2580 ArgType = SemaRef.SubstType(ArgType, AllTemplateArgs,
2581 Param->getDefaultArgumentLoc(),
2582 Param->getDeclName());
2588 /// \brief Substitute template arguments into the default template argument for
2589 /// the given non-type template parameter.
2591 /// \param SemaRef the semantic analysis object for which we are performing
2592 /// the substitution.
2594 /// \param Template the template that we are synthesizing template arguments
2597 /// \param TemplateLoc the location of the template name that started the
2598 /// template-id we are checking.
2600 /// \param RAngleLoc the location of the right angle bracket ('>') that
2601 /// terminates the template-id.
2603 /// \param Param the non-type template parameter whose default we are
2604 /// substituting into.
2606 /// \param Converted the list of template arguments provided for template
2607 /// parameters that precede \p Param in the template parameter list.
2609 /// \returns the substituted template argument, or NULL if an error occurred.
2611 SubstDefaultTemplateArgument(Sema &SemaRef,
2612 TemplateDecl *Template,
2613 SourceLocation TemplateLoc,
2614 SourceLocation RAngleLoc,
2615 NonTypeTemplateParmDecl *Param,
2616 SmallVectorImpl<TemplateArgument> &Converted) {
2617 TemplateArgumentList TemplateArgs(TemplateArgumentList::OnStack,
2618 Converted.data(), Converted.size());
2620 MultiLevelTemplateArgumentList AllTemplateArgs
2621 = SemaRef.getTemplateInstantiationArgs(Template, &TemplateArgs);
2623 Sema::InstantiatingTemplate Inst(SemaRef, TemplateLoc,
2624 Template, Converted,
2625 SourceRange(TemplateLoc, RAngleLoc));
2629 Sema::ContextRAII SavedContext(SemaRef, Template->getDeclContext());
2630 EnterExpressionEvaluationContext Unevaluated(SemaRef, Sema::Unevaluated);
2631 return SemaRef.SubstExpr(Param->getDefaultArgument(), AllTemplateArgs);
2634 /// \brief Substitute template arguments into the default template argument for
2635 /// the given template template parameter.
2637 /// \param SemaRef the semantic analysis object for which we are performing
2638 /// the substitution.
2640 /// \param Template the template that we are synthesizing template arguments
2643 /// \param TemplateLoc the location of the template name that started the
2644 /// template-id we are checking.
2646 /// \param RAngleLoc the location of the right angle bracket ('>') that
2647 /// terminates the template-id.
2649 /// \param Param the template template parameter whose default we are
2650 /// substituting into.
2652 /// \param Converted the list of template arguments provided for template
2653 /// parameters that precede \p Param in the template parameter list.
2655 /// \param QualifierLoc Will be set to the nested-name-specifier (with
2656 /// source-location information) that precedes the template name.
2658 /// \returns the substituted template argument, or NULL if an error occurred.
2660 SubstDefaultTemplateArgument(Sema &SemaRef,
2661 TemplateDecl *Template,
2662 SourceLocation TemplateLoc,
2663 SourceLocation RAngleLoc,
2664 TemplateTemplateParmDecl *Param,
2665 SmallVectorImpl<TemplateArgument> &Converted,
2666 NestedNameSpecifierLoc &QualifierLoc) {
2667 TemplateArgumentList TemplateArgs(TemplateArgumentList::OnStack,
2668 Converted.data(), Converted.size());
2670 MultiLevelTemplateArgumentList AllTemplateArgs
2671 = SemaRef.getTemplateInstantiationArgs(Template, &TemplateArgs);
2673 Sema::InstantiatingTemplate Inst(SemaRef, TemplateLoc,
2674 Template, Converted,
2675 SourceRange(TemplateLoc, RAngleLoc));
2677 return TemplateName();
2679 Sema::ContextRAII SavedContext(SemaRef, Template->getDeclContext());
2680 // Substitute into the nested-name-specifier first,
2681 QualifierLoc = Param->getDefaultArgument().getTemplateQualifierLoc();
2683 QualifierLoc = SemaRef.SubstNestedNameSpecifierLoc(QualifierLoc,
2686 return TemplateName();
2689 return SemaRef.SubstTemplateName(QualifierLoc,
2690 Param->getDefaultArgument().getArgument().getAsTemplate(),
2691 Param->getDefaultArgument().getTemplateNameLoc(),
2695 /// \brief If the given template parameter has a default template
2696 /// argument, substitute into that default template argument and
2697 /// return the corresponding template argument.
2699 Sema::SubstDefaultTemplateArgumentIfAvailable(TemplateDecl *Template,
2700 SourceLocation TemplateLoc,
2701 SourceLocation RAngleLoc,
2703 SmallVectorImpl<TemplateArgument> &Converted) {
2704 if (TemplateTypeParmDecl *TypeParm = dyn_cast<TemplateTypeParmDecl>(Param)) {
2705 if (!TypeParm->hasDefaultArgument())
2706 return TemplateArgumentLoc();
2708 TypeSourceInfo *DI = SubstDefaultTemplateArgument(*this, Template,
2714 return TemplateArgumentLoc(TemplateArgument(DI->getType()), DI);
2716 return TemplateArgumentLoc();
2719 if (NonTypeTemplateParmDecl *NonTypeParm
2720 = dyn_cast<NonTypeTemplateParmDecl>(Param)) {
2721 if (!NonTypeParm->hasDefaultArgument())
2722 return TemplateArgumentLoc();
2724 ExprResult Arg = SubstDefaultTemplateArgument(*this, Template,
2729 if (Arg.isInvalid())
2730 return TemplateArgumentLoc();
2732 Expr *ArgE = Arg.takeAs<Expr>();
2733 return TemplateArgumentLoc(TemplateArgument(ArgE), ArgE);
2736 TemplateTemplateParmDecl *TempTempParm
2737 = cast<TemplateTemplateParmDecl>(Param);
2738 if (!TempTempParm->hasDefaultArgument())
2739 return TemplateArgumentLoc();
2742 NestedNameSpecifierLoc QualifierLoc;
2743 TemplateName TName = SubstDefaultTemplateArgument(*this, Template,
2750 return TemplateArgumentLoc();
2752 return TemplateArgumentLoc(TemplateArgument(TName),
2753 TempTempParm->getDefaultArgument().getTemplateQualifierLoc(),
2754 TempTempParm->getDefaultArgument().getTemplateNameLoc());
2757 /// \brief Check that the given template argument corresponds to the given
2758 /// template parameter.
2760 /// \param Param The template parameter against which the argument will be
2763 /// \param Arg The template argument.
2765 /// \param Template The template in which the template argument resides.
2767 /// \param TemplateLoc The location of the template name for the template
2768 /// whose argument list we're matching.
2770 /// \param RAngleLoc The location of the right angle bracket ('>') that closes
2771 /// the template argument list.
2773 /// \param ArgumentPackIndex The index into the argument pack where this
2774 /// argument will be placed. Only valid if the parameter is a parameter pack.
2776 /// \param Converted The checked, converted argument will be added to the
2777 /// end of this small vector.
2779 /// \param CTAK Describes how we arrived at this particular template argument:
2780 /// explicitly written, deduced, etc.
2782 /// \returns true on error, false otherwise.
2783 bool Sema::CheckTemplateArgument(NamedDecl *Param,
2784 const TemplateArgumentLoc &Arg,
2785 NamedDecl *Template,
2786 SourceLocation TemplateLoc,
2787 SourceLocation RAngleLoc,
2788 unsigned ArgumentPackIndex,
2789 SmallVectorImpl<TemplateArgument> &Converted,
2790 CheckTemplateArgumentKind CTAK) {
2791 // Check template type parameters.
2792 if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(Param))
2793 return CheckTemplateTypeArgument(TTP, Arg, Converted);
2795 // Check non-type template parameters.
2796 if (NonTypeTemplateParmDecl *NTTP =dyn_cast<NonTypeTemplateParmDecl>(Param)) {
2797 // Do substitution on the type of the non-type template parameter
2798 // with the template arguments we've seen thus far. But if the
2799 // template has a dependent context then we cannot substitute yet.
2800 QualType NTTPType = NTTP->getType();
2801 if (NTTP->isParameterPack() && NTTP->isExpandedParameterPack())
2802 NTTPType = NTTP->getExpansionType(ArgumentPackIndex);
2804 if (NTTPType->isDependentType() &&
2805 !isa<TemplateTemplateParmDecl>(Template) &&
2806 !Template->getDeclContext()->isDependentContext()) {
2807 // Do substitution on the type of the non-type template parameter.
2808 InstantiatingTemplate Inst(*this, TemplateLoc, Template,
2810 SourceRange(TemplateLoc, RAngleLoc));
2814 TemplateArgumentList TemplateArgs(TemplateArgumentList::OnStack,
2815 Converted.data(), Converted.size());
2816 NTTPType = SubstType(NTTPType,
2817 MultiLevelTemplateArgumentList(TemplateArgs),
2818 NTTP->getLocation(),
2819 NTTP->getDeclName());
2820 // If that worked, check the non-type template parameter type
2822 if (!NTTPType.isNull())
2823 NTTPType = CheckNonTypeTemplateParameterType(NTTPType,
2824 NTTP->getLocation());
2825 if (NTTPType.isNull())
2829 switch (Arg.getArgument().getKind()) {
2830 case TemplateArgument::Null:
2831 llvm_unreachable("Should never see a NULL template argument here");
2833 case TemplateArgument::Expression: {
2834 TemplateArgument Result;
2836 CheckTemplateArgument(NTTP, NTTPType, Arg.getArgument().getAsExpr(),
2838 if (Res.isInvalid())
2841 Converted.push_back(Result);
2845 case TemplateArgument::Declaration:
2846 case TemplateArgument::Integral:
2847 case TemplateArgument::NullPtr:
2848 // We've already checked this template argument, so just copy
2849 // it to the list of converted arguments.
2850 Converted.push_back(Arg.getArgument());
2853 case TemplateArgument::Template:
2854 case TemplateArgument::TemplateExpansion:
2855 // We were given a template template argument. It may not be ill-formed;
2857 if (DependentTemplateName *DTN
2858 = Arg.getArgument().getAsTemplateOrTemplatePattern()
2859 .getAsDependentTemplateName()) {
2860 // We have a template argument such as \c T::template X, which we
2861 // parsed as a template template argument. However, since we now
2862 // know that we need a non-type template argument, convert this
2863 // template name into an expression.
2865 DeclarationNameInfo NameInfo(DTN->getIdentifier(),
2866 Arg.getTemplateNameLoc());
2869 SS.Adopt(Arg.getTemplateQualifierLoc());
2870 // FIXME: the template-template arg was a DependentTemplateName,
2871 // so it was provided with a template keyword. However, its source
2872 // location is not stored in the template argument structure.
2873 SourceLocation TemplateKWLoc;
2874 ExprResult E = Owned(DependentScopeDeclRefExpr::Create(Context,
2875 SS.getWithLocInContext(Context),
2879 // If we parsed the template argument as a pack expansion, create a
2880 // pack expansion expression.
2881 if (Arg.getArgument().getKind() == TemplateArgument::TemplateExpansion){
2882 E = ActOnPackExpansion(E.take(), Arg.getTemplateEllipsisLoc());
2887 TemplateArgument Result;
2888 E = CheckTemplateArgument(NTTP, NTTPType, E.take(), Result);
2892 Converted.push_back(Result);
2896 // We have a template argument that actually does refer to a class
2897 // template, alias template, or template template parameter, and
2898 // therefore cannot be a non-type template argument.
2899 Diag(Arg.getLocation(), diag::err_template_arg_must_be_expr)
2900 << Arg.getSourceRange();
2902 Diag(Param->getLocation(), diag::note_template_param_here);
2905 case TemplateArgument::Type: {
2906 // We have a non-type template parameter but the template
2907 // argument is a type.
2909 // C++ [temp.arg]p2:
2910 // In a template-argument, an ambiguity between a type-id and
2911 // an expression is resolved to a type-id, regardless of the
2912 // form of the corresponding template-parameter.
2914 // We warn specifically about this case, since it can be rather
2915 // confusing for users.
2916 QualType T = Arg.getArgument().getAsType();
2917 SourceRange SR = Arg.getSourceRange();
2918 if (T->isFunctionType())
2919 Diag(SR.getBegin(), diag::err_template_arg_nontype_ambig) << SR << T;
2921 Diag(SR.getBegin(), diag::err_template_arg_must_be_expr) << SR;
2922 Diag(Param->getLocation(), diag::note_template_param_here);
2926 case TemplateArgument::Pack:
2927 llvm_unreachable("Caller must expand template argument packs");
2934 // Check template template parameters.
2935 TemplateTemplateParmDecl *TempParm = cast<TemplateTemplateParmDecl>(Param);
2937 // Substitute into the template parameter list of the template
2938 // template parameter, since previously-supplied template arguments
2939 // may appear within the template template parameter.
2941 // Set up a template instantiation context.
2942 LocalInstantiationScope Scope(*this);
2943 InstantiatingTemplate Inst(*this, TemplateLoc, Template,
2944 TempParm, Converted,
2945 SourceRange(TemplateLoc, RAngleLoc));
2949 TemplateArgumentList TemplateArgs(TemplateArgumentList::OnStack,
2950 Converted.data(), Converted.size());
2951 TempParm = cast_or_null<TemplateTemplateParmDecl>(
2952 SubstDecl(TempParm, CurContext,
2953 MultiLevelTemplateArgumentList(TemplateArgs)));
2958 switch (Arg.getArgument().getKind()) {
2959 case TemplateArgument::Null:
2960 llvm_unreachable("Should never see a NULL template argument here");
2962 case TemplateArgument::Template:
2963 case TemplateArgument::TemplateExpansion:
2964 if (CheckTemplateArgument(TempParm, Arg, ArgumentPackIndex))
2967 Converted.push_back(Arg.getArgument());
2970 case TemplateArgument::Expression:
2971 case TemplateArgument::Type:
2972 // We have a template template parameter but the template
2973 // argument does not refer to a template.
2974 Diag(Arg.getLocation(), diag::err_template_arg_must_be_template)
2975 << getLangOpts().CPlusPlus11;
2978 case TemplateArgument::Declaration:
2979 llvm_unreachable("Declaration argument with template template parameter");
2980 case TemplateArgument::Integral:
2981 llvm_unreachable("Integral argument with template template parameter");
2982 case TemplateArgument::NullPtr:
2983 llvm_unreachable("Null pointer argument with template template parameter");
2985 case TemplateArgument::Pack:
2986 llvm_unreachable("Caller must expand template argument packs");
2992 /// \brief Diagnose an arity mismatch in the
2993 static bool diagnoseArityMismatch(Sema &S, TemplateDecl *Template,
2994 SourceLocation TemplateLoc,
2995 TemplateArgumentListInfo &TemplateArgs) {
2996 TemplateParameterList *Params = Template->getTemplateParameters();
2997 unsigned NumParams = Params->size();
2998 unsigned NumArgs = TemplateArgs.size();
3001 if (NumArgs > NumParams)
3002 Range = SourceRange(TemplateArgs[NumParams].getLocation(),
3003 TemplateArgs.getRAngleLoc());
3004 S.Diag(TemplateLoc, diag::err_template_arg_list_different_arity)
3005 << (NumArgs > NumParams)
3006 << (isa<ClassTemplateDecl>(Template)? 0 :
3007 isa<FunctionTemplateDecl>(Template)? 1 :
3008 isa<TemplateTemplateParmDecl>(Template)? 2 : 3)
3009 << Template << Range;
3010 S.Diag(Template->getLocation(), diag::note_template_decl_here)
3011 << Params->getSourceRange();
3015 /// \brief Check whether the template parameter is a pack expansion, and if so,
3016 /// determine the number of parameters produced by that expansion. For instance:
3019 /// template<typename ...Ts> struct A {
3020 /// template<Ts ...NTs, template<Ts> class ...TTs, typename ...Us> struct B;
3024 /// In \c A<int,int>::B, \c NTs and \c TTs have expanded pack size 2, and \c Us
3025 /// is not a pack expansion, so returns an empty Optional.
3026 static Optional<unsigned> getExpandedPackSize(NamedDecl *Param) {
3027 if (NonTypeTemplateParmDecl *NTTP
3028 = dyn_cast<NonTypeTemplateParmDecl>(Param)) {
3029 if (NTTP->isExpandedParameterPack())
3030 return NTTP->getNumExpansionTypes();
3033 if (TemplateTemplateParmDecl *TTP
3034 = dyn_cast<TemplateTemplateParmDecl>(Param)) {
3035 if (TTP->isExpandedParameterPack())
3036 return TTP->getNumExpansionTemplateParameters();
3042 /// \brief Check that the given template argument list is well-formed
3043 /// for specializing the given template.
3044 bool Sema::CheckTemplateArgumentList(TemplateDecl *Template,
3045 SourceLocation TemplateLoc,
3046 TemplateArgumentListInfo &TemplateArgs,
3047 bool PartialTemplateArgs,
3048 SmallVectorImpl<TemplateArgument> &Converted,
3049 bool *ExpansionIntoFixedList) {
3050 if (ExpansionIntoFixedList)
3051 *ExpansionIntoFixedList = false;
3053 TemplateParameterList *Params = Template->getTemplateParameters();
3055 SourceLocation RAngleLoc = TemplateArgs.getRAngleLoc();
3057 // C++ [temp.arg]p1:
3058 // [...] The type and form of each template-argument specified in
3059 // a template-id shall match the type and form specified for the
3060 // corresponding parameter declared by the template in its
3061 // template-parameter-list.
3062 bool isTemplateTemplateParameter = isa<TemplateTemplateParmDecl>(Template);
3063 SmallVector<TemplateArgument, 2> ArgumentPack;
3064 unsigned ArgIdx = 0, NumArgs = TemplateArgs.size();
3065 LocalInstantiationScope InstScope(*this, true);
3066 for (TemplateParameterList::iterator Param = Params->begin(),
3067 ParamEnd = Params->end();
3068 Param != ParamEnd; /* increment in loop */) {
3069 // If we have an expanded parameter pack, make sure we don't have too
3071 if (Optional<unsigned> Expansions = getExpandedPackSize(*Param)) {
3072 if (*Expansions == ArgumentPack.size()) {
3073 // We're done with this parameter pack. Pack up its arguments and add
3074 // them to the list.
3075 Converted.push_back(
3076 TemplateArgument::CreatePackCopy(Context,
3077 ArgumentPack.data(),
3078 ArgumentPack.size()));
3079 ArgumentPack.clear();
3081 // This argument is assigned to the next parameter.
3084 } else if (ArgIdx == NumArgs && !PartialTemplateArgs) {
3085 // Not enough arguments for this parameter pack.
3086 Diag(TemplateLoc, diag::err_template_arg_list_different_arity)
3088 << (isa<ClassTemplateDecl>(Template)? 0 :
3089 isa<FunctionTemplateDecl>(Template)? 1 :
3090 isa<TemplateTemplateParmDecl>(Template)? 2 : 3)
3092 Diag(Template->getLocation(), diag::note_template_decl_here)
3093 << Params->getSourceRange();
3098 if (ArgIdx < NumArgs) {
3099 // Check the template argument we were given.
3100 if (CheckTemplateArgument(*Param, TemplateArgs[ArgIdx], Template,
3101 TemplateLoc, RAngleLoc,
3102 ArgumentPack.size(), Converted))
3105 // We're now done with this argument.
3108 if ((*Param)->isTemplateParameterPack()) {
3109 // The template parameter was a template parameter pack, so take the
3110 // deduced argument and place it on the argument pack. Note that we
3111 // stay on the same template parameter so that we can deduce more
3113 ArgumentPack.push_back(Converted.back());
3114 Converted.pop_back();
3116 // Move to the next template parameter.
3120 // If we just saw a pack expansion, then directly convert the remaining
3121 // arguments, because we don't know what parameters they'll match up
3123 if (TemplateArgs[ArgIdx-1].getArgument().isPackExpansion()) {
3124 bool InFinalParameterPack = Param != ParamEnd &&
3125 Param + 1 == ParamEnd &&
3126 (*Param)->isTemplateParameterPack() &&
3127 !getExpandedPackSize(*Param);
3129 if (!InFinalParameterPack && !ArgumentPack.empty()) {
3130 // If we were part way through filling in an expanded parameter pack,
3131 // fall back to just producing individual arguments.
3132 Converted.insert(Converted.end(),
3133 ArgumentPack.begin(), ArgumentPack.end());
3134 ArgumentPack.clear();
3137 while (ArgIdx < NumArgs) {
3138 if (InFinalParameterPack)
3139 ArgumentPack.push_back(TemplateArgs[ArgIdx].getArgument());
3141 Converted.push_back(TemplateArgs[ArgIdx].getArgument());
3145 // Push the argument pack onto the list of converted arguments.
3146 if (InFinalParameterPack) {
3147 Converted.push_back(
3148 TemplateArgument::CreatePackCopy(Context,
3149 ArgumentPack.data(),
3150 ArgumentPack.size()));
3151 ArgumentPack.clear();
3152 } else if (ExpansionIntoFixedList) {
3153 // We have expanded a pack into a fixed list.
3154 *ExpansionIntoFixedList = true;
3163 // If we're checking a partial template argument list, we're done.
3164 if (PartialTemplateArgs) {
3165 if ((*Param)->isTemplateParameterPack() && !ArgumentPack.empty())
3166 Converted.push_back(TemplateArgument::CreatePackCopy(Context,
3167 ArgumentPack.data(),
3168 ArgumentPack.size()));
3173 // If we have a template parameter pack with no more corresponding
3174 // arguments, just break out now and we'll fill in the argument pack below.
3175 if ((*Param)->isTemplateParameterPack()) {
3176 assert(!getExpandedPackSize(*Param) &&
3177 "Should have dealt with this already");
3179 // A non-expanded parameter pack before the end of the parameter list
3180 // only occurs for an ill-formed template parameter list, unless we've
3181 // got a partial argument list for a function template, so just bail out.
3182 if (Param + 1 != ParamEnd)
3185 Converted.push_back(TemplateArgument::CreatePackCopy(Context,
3186 ArgumentPack.data(),
3187 ArgumentPack.size()));
3188 ArgumentPack.clear();
3194 // Check whether we have a default argument.
3195 TemplateArgumentLoc Arg;
3197 // Retrieve the default template argument from the template
3198 // parameter. For each kind of template parameter, we substitute the
3199 // template arguments provided thus far and any "outer" template arguments
3200 // (when the template parameter was part of a nested template) into
3201 // the default argument.
3202 if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(*Param)) {
3203 if (!TTP->hasDefaultArgument())
3204 return diagnoseArityMismatch(*this, Template, TemplateLoc,
3207 TypeSourceInfo *ArgType = SubstDefaultTemplateArgument(*this,
3216 Arg = TemplateArgumentLoc(TemplateArgument(ArgType->getType()),
3218 } else if (NonTypeTemplateParmDecl *NTTP
3219 = dyn_cast<NonTypeTemplateParmDecl>(*Param)) {
3220 if (!NTTP->hasDefaultArgument())
3221 return diagnoseArityMismatch(*this, Template, TemplateLoc,
3224 ExprResult E = SubstDefaultTemplateArgument(*this, Template,
3232 Expr *Ex = E.takeAs<Expr>();
3233 Arg = TemplateArgumentLoc(TemplateArgument(Ex), Ex);
3235 TemplateTemplateParmDecl *TempParm
3236 = cast<TemplateTemplateParmDecl>(*Param);
3238 if (!TempParm->hasDefaultArgument())
3239 return diagnoseArityMismatch(*this, Template, TemplateLoc,
3242 NestedNameSpecifierLoc QualifierLoc;
3243 TemplateName Name = SubstDefaultTemplateArgument(*this, Template,
3252 Arg = TemplateArgumentLoc(TemplateArgument(Name), QualifierLoc,
3253 TempParm->getDefaultArgument().getTemplateNameLoc());
3256 // Introduce an instantiation record that describes where we are using
3257 // the default template argument.
3258 InstantiatingTemplate Instantiating(*this, RAngleLoc, Template,
3260 SourceRange(TemplateLoc, RAngleLoc));
3264 // Check the default template argument.
3265 if (CheckTemplateArgument(*Param, Arg, Template, TemplateLoc,
3266 RAngleLoc, 0, Converted))
3269 // Core issue 150 (assumed resolution): if this is a template template
3270 // parameter, keep track of the default template arguments from the
3271 // template definition.
3272 if (isTemplateTemplateParameter)
3273 TemplateArgs.addArgument(Arg);
3275 // Move to the next template parameter and argument.
3280 // If we have any leftover arguments, then there were too many arguments.
3281 // Complain and fail.
3282 if (ArgIdx < NumArgs)
3283 return diagnoseArityMismatch(*this, Template, TemplateLoc, TemplateArgs);
3289 class UnnamedLocalNoLinkageFinder
3290 : public TypeVisitor<UnnamedLocalNoLinkageFinder, bool>
3295 typedef TypeVisitor<UnnamedLocalNoLinkageFinder, bool> inherited;
3298 UnnamedLocalNoLinkageFinder(Sema &S, SourceRange SR) : S(S), SR(SR) { }
3300 bool Visit(QualType T) {
3301 return inherited::Visit(T.getTypePtr());
3304 #define TYPE(Class, Parent) \
3305 bool Visit##Class##Type(const Class##Type *);
3306 #define ABSTRACT_TYPE(Class, Parent) \
3307 bool Visit##Class##Type(const Class##Type *) { return false; }
3308 #define NON_CANONICAL_TYPE(Class, Parent) \
3309 bool Visit##Class##Type(const Class##Type *) { return false; }
3310 #include "clang/AST/TypeNodes.def"
3312 bool VisitTagDecl(const TagDecl *Tag);
3313 bool VisitNestedNameSpecifier(NestedNameSpecifier *NNS);
3317 bool UnnamedLocalNoLinkageFinder::VisitBuiltinType(const BuiltinType*) {
3321 bool UnnamedLocalNoLinkageFinder::VisitComplexType(const ComplexType* T) {
3322 return Visit(T->getElementType());
3325 bool UnnamedLocalNoLinkageFinder::VisitPointerType(const PointerType* T) {
3326 return Visit(T->getPointeeType());
3329 bool UnnamedLocalNoLinkageFinder::VisitBlockPointerType(
3330 const BlockPointerType* T) {
3331 return Visit(T->getPointeeType());
3334 bool UnnamedLocalNoLinkageFinder::VisitLValueReferenceType(
3335 const LValueReferenceType* T) {
3336 return Visit(T->getPointeeType());
3339 bool UnnamedLocalNoLinkageFinder::VisitRValueReferenceType(
3340 const RValueReferenceType* T) {
3341 return Visit(T->getPointeeType());
3344 bool UnnamedLocalNoLinkageFinder::VisitMemberPointerType(
3345 const MemberPointerType* T) {
3346 return Visit(T->getPointeeType()) || Visit(QualType(T->getClass(), 0));
3349 bool UnnamedLocalNoLinkageFinder::VisitConstantArrayType(
3350 const ConstantArrayType* T) {
3351 return Visit(T->getElementType());
3354 bool UnnamedLocalNoLinkageFinder::VisitIncompleteArrayType(
3355 const IncompleteArrayType* T) {
3356 return Visit(T->getElementType());
3359 bool UnnamedLocalNoLinkageFinder::VisitVariableArrayType(
3360 const VariableArrayType* T) {
3361 return Visit(T->getElementType());
3364 bool UnnamedLocalNoLinkageFinder::VisitDependentSizedArrayType(
3365 const DependentSizedArrayType* T) {
3366 return Visit(T->getElementType());
3369 bool UnnamedLocalNoLinkageFinder::VisitDependentSizedExtVectorType(
3370 const DependentSizedExtVectorType* T) {
3371 return Visit(T->getElementType());
3374 bool UnnamedLocalNoLinkageFinder::VisitVectorType(const VectorType* T) {
3375 return Visit(T->getElementType());
3378 bool UnnamedLocalNoLinkageFinder::VisitExtVectorType(const ExtVectorType* T) {
3379 return Visit(T->getElementType());
3382 bool UnnamedLocalNoLinkageFinder::VisitFunctionProtoType(
3383 const FunctionProtoType* T) {
3384 for (FunctionProtoType::arg_type_iterator A = T->arg_type_begin(),
3385 AEnd = T->arg_type_end();
3391 return Visit(T->getResultType());
3394 bool UnnamedLocalNoLinkageFinder::VisitFunctionNoProtoType(
3395 const FunctionNoProtoType* T) {
3396 return Visit(T->getResultType());
3399 bool UnnamedLocalNoLinkageFinder::VisitUnresolvedUsingType(
3400 const UnresolvedUsingType*) {
3404 bool UnnamedLocalNoLinkageFinder::VisitTypeOfExprType(const TypeOfExprType*) {
3408 bool UnnamedLocalNoLinkageFinder::VisitTypeOfType(const TypeOfType* T) {
3409 return Visit(T->getUnderlyingType());
3412 bool UnnamedLocalNoLinkageFinder::VisitDecltypeType(const DecltypeType*) {
3416 bool UnnamedLocalNoLinkageFinder::VisitUnaryTransformType(
3417 const UnaryTransformType*) {
3421 bool UnnamedLocalNoLinkageFinder::VisitAutoType(const AutoType *T) {
3422 return Visit(T->getDeducedType());
3425 bool UnnamedLocalNoLinkageFinder::VisitRecordType(const RecordType* T) {
3426 return VisitTagDecl(T->getDecl());
3429 bool UnnamedLocalNoLinkageFinder::VisitEnumType(const EnumType* T) {
3430 return VisitTagDecl(T->getDecl());
3433 bool UnnamedLocalNoLinkageFinder::VisitTemplateTypeParmType(
3434 const TemplateTypeParmType*) {
3438 bool UnnamedLocalNoLinkageFinder::VisitSubstTemplateTypeParmPackType(
3439 const SubstTemplateTypeParmPackType *) {
3443 bool UnnamedLocalNoLinkageFinder::VisitTemplateSpecializationType(
3444 const TemplateSpecializationType*) {
3448 bool UnnamedLocalNoLinkageFinder::VisitInjectedClassNameType(
3449 const InjectedClassNameType* T) {
3450 return VisitTagDecl(T->getDecl());
3453 bool UnnamedLocalNoLinkageFinder::VisitDependentNameType(
3454 const DependentNameType* T) {
3455 return VisitNestedNameSpecifier(T->getQualifier());
3458 bool UnnamedLocalNoLinkageFinder::VisitDependentTemplateSpecializationType(
3459 const DependentTemplateSpecializationType* T) {
3460 return VisitNestedNameSpecifier(T->getQualifier());
3463 bool UnnamedLocalNoLinkageFinder::VisitPackExpansionType(
3464 const PackExpansionType* T) {
3465 return Visit(T->getPattern());
3468 bool UnnamedLocalNoLinkageFinder::VisitObjCObjectType(const ObjCObjectType *) {
3472 bool UnnamedLocalNoLinkageFinder::VisitObjCInterfaceType(
3473 const ObjCInterfaceType *) {
3477 bool UnnamedLocalNoLinkageFinder::VisitObjCObjectPointerType(
3478 const ObjCObjectPointerType *) {
3482 bool UnnamedLocalNoLinkageFinder::VisitAtomicType(const AtomicType* T) {
3483 return Visit(T->getValueType());
3486 bool UnnamedLocalNoLinkageFinder::VisitTagDecl(const TagDecl *Tag) {
3487 if (Tag->getDeclContext()->isFunctionOrMethod()) {
3488 S.Diag(SR.getBegin(),
3489 S.getLangOpts().CPlusPlus11 ?
3490 diag::warn_cxx98_compat_template_arg_local_type :
3491 diag::ext_template_arg_local_type)
3492 << S.Context.getTypeDeclType(Tag) << SR;
3496 if (!Tag->hasNameForLinkage()) {
3497 S.Diag(SR.getBegin(),
3498 S.getLangOpts().CPlusPlus11 ?
3499 diag::warn_cxx98_compat_template_arg_unnamed_type :
3500 diag::ext_template_arg_unnamed_type) << SR;
3501 S.Diag(Tag->getLocation(), diag::note_template_unnamed_type_here);
3508 bool UnnamedLocalNoLinkageFinder::VisitNestedNameSpecifier(
3509 NestedNameSpecifier *NNS) {
3510 if (NNS->getPrefix() && VisitNestedNameSpecifier(NNS->getPrefix()))
3513 switch (NNS->getKind()) {
3514 case NestedNameSpecifier::Identifier:
3515 case NestedNameSpecifier::Namespace:
3516 case NestedNameSpecifier::NamespaceAlias:
3517 case NestedNameSpecifier::Global:
3520 case NestedNameSpecifier::TypeSpec:
3521 case NestedNameSpecifier::TypeSpecWithTemplate:
3522 return Visit(QualType(NNS->getAsType(), 0));
3524 llvm_unreachable("Invalid NestedNameSpecifier::Kind!");
3528 /// \brief Check a template argument against its corresponding
3529 /// template type parameter.
3531 /// This routine implements the semantics of C++ [temp.arg.type]. It
3532 /// returns true if an error occurred, and false otherwise.
3533 bool Sema::CheckTemplateArgument(TemplateTypeParmDecl *Param,
3534 TypeSourceInfo *ArgInfo) {
3535 assert(ArgInfo && "invalid TypeSourceInfo");
3536 QualType Arg = ArgInfo->getType();
3537 SourceRange SR = ArgInfo->getTypeLoc().getSourceRange();
3539 if (Arg->isVariablyModifiedType()) {
3540 return Diag(SR.getBegin(), diag::err_variably_modified_template_arg) << Arg;
3541 } else if (Context.hasSameUnqualifiedType(Arg, Context.OverloadTy)) {
3542 return Diag(SR.getBegin(), diag::err_template_arg_overload_type) << SR;
3545 // C++03 [temp.arg.type]p2:
3546 // A local type, a type with no linkage, an unnamed type or a type
3547 // compounded from any of these types shall not be used as a
3548 // template-argument for a template type-parameter.
3550 // C++11 allows these, and even in C++03 we allow them as an extension with
3552 if (LangOpts.CPlusPlus11 ?
3553 Diags.getDiagnosticLevel(diag::warn_cxx98_compat_template_arg_unnamed_type,
3554 SR.getBegin()) != DiagnosticsEngine::Ignored ||
3555 Diags.getDiagnosticLevel(diag::warn_cxx98_compat_template_arg_local_type,
3556 SR.getBegin()) != DiagnosticsEngine::Ignored :
3557 Arg->hasUnnamedOrLocalType()) {
3558 UnnamedLocalNoLinkageFinder Finder(*this, SR);
3559 (void)Finder.Visit(Context.getCanonicalType(Arg));
3565 enum NullPointerValueKind {
3571 /// \brief Determine whether the given template argument is a null pointer
3572 /// value of the appropriate type.
3573 static NullPointerValueKind
3574 isNullPointerValueTemplateArgument(Sema &S, NonTypeTemplateParmDecl *Param,
3575 QualType ParamType, Expr *Arg) {
3576 if (Arg->isValueDependent() || Arg->isTypeDependent())
3577 return NPV_NotNullPointer;
3579 if (!S.getLangOpts().CPlusPlus11)
3580 return NPV_NotNullPointer;
3582 // Determine whether we have a constant expression.
3583 ExprResult ArgRV = S.DefaultFunctionArrayConversion(Arg);
3584 if (ArgRV.isInvalid())
3588 Expr::EvalResult EvalResult;
3589 SmallVector<PartialDiagnosticAt, 8> Notes;
3590 EvalResult.Diag = &Notes;
3591 if (!Arg->EvaluateAsRValue(EvalResult, S.Context) ||
3592 EvalResult.HasSideEffects) {
3593 SourceLocation DiagLoc = Arg->getExprLoc();
3595 // If our only note is the usual "invalid subexpression" note, just point
3596 // the caret at its location rather than producing an essentially
3598 if (Notes.size() == 1 && Notes[0].second.getDiagID() ==
3599 diag::note_invalid_subexpr_in_const_expr) {
3600 DiagLoc = Notes[0].first;
3604 S.Diag(DiagLoc, diag::err_template_arg_not_address_constant)
3605 << Arg->getType() << Arg->getSourceRange();
3606 for (unsigned I = 0, N = Notes.size(); I != N; ++I)
3607 S.Diag(Notes[I].first, Notes[I].second);
3609 S.Diag(Param->getLocation(), diag::note_template_param_here);
3613 // C++11 [temp.arg.nontype]p1:
3614 // - an address constant expression of type std::nullptr_t
3615 if (Arg->getType()->isNullPtrType())
3616 return NPV_NullPointer;
3618 // - a constant expression that evaluates to a null pointer value (4.10); or
3619 // - a constant expression that evaluates to a null member pointer value
3621 if ((EvalResult.Val.isLValue() && !EvalResult.Val.getLValueBase()) ||
3622 (EvalResult.Val.isMemberPointer() &&
3623 !EvalResult.Val.getMemberPointerDecl())) {
3624 // If our expression has an appropriate type, we've succeeded.
3625 bool ObjCLifetimeConversion;
3626 if (S.Context.hasSameUnqualifiedType(Arg->getType(), ParamType) ||
3627 S.IsQualificationConversion(Arg->getType(), ParamType, false,
3628 ObjCLifetimeConversion))
3629 return NPV_NullPointer;
3631 // The types didn't match, but we know we got a null pointer; complain,
3632 // then recover as if the types were correct.
3633 S.Diag(Arg->getExprLoc(), diag::err_template_arg_wrongtype_null_constant)
3634 << Arg->getType() << ParamType << Arg->getSourceRange();
3635 S.Diag(Param->getLocation(), diag::note_template_param_here);
3636 return NPV_NullPointer;
3639 // If we don't have a null pointer value, but we do have a NULL pointer
3640 // constant, suggest a cast to the appropriate type.
3641 if (Arg->isNullPointerConstant(S.Context, Expr::NPC_NeverValueDependent)) {
3642 std::string Code = "static_cast<" + ParamType.getAsString() + ">(";
3643 S.Diag(Arg->getExprLoc(), diag::err_template_arg_untyped_null_constant)
3645 << FixItHint::CreateInsertion(Arg->getLocStart(), Code)
3646 << FixItHint::CreateInsertion(S.PP.getLocForEndOfToken(Arg->getLocEnd()),
3648 S.Diag(Param->getLocation(), diag::note_template_param_here);
3649 return NPV_NullPointer;
3652 // FIXME: If we ever want to support general, address-constant expressions
3653 // as non-type template arguments, we should return the ExprResult here to
3654 // be interpreted by the caller.
3655 return NPV_NotNullPointer;
3658 /// \brief Checks whether the given template argument is the address
3659 /// of an object or function according to C++ [temp.arg.nontype]p1.
3661 CheckTemplateArgumentAddressOfObjectOrFunction(Sema &S,
3662 NonTypeTemplateParmDecl *Param,
3665 TemplateArgument &Converted) {
3666 bool Invalid = false;
3668 QualType ArgType = Arg->getType();
3670 // If our parameter has pointer type, check for a null template value.
3671 if (ParamType->isPointerType() || ParamType->isNullPtrType()) {
3672 switch (isNullPointerValueTemplateArgument(S, Param, ParamType, Arg)) {
3673 case NPV_NullPointer:
3674 S.Diag(Arg->getExprLoc(), diag::warn_cxx98_compat_template_arg_null);
3675 Converted = TemplateArgument(ParamType, /*isNullPtr*/true);
3681 case NPV_NotNullPointer:
3686 // See through any implicit casts we added to fix the type.
3687 Arg = Arg->IgnoreImpCasts();
3689 // C++ [temp.arg.nontype]p1:
3691 // A template-argument for a non-type, non-template
3692 // template-parameter shall be one of: [...]
3694 // -- the address of an object or function with external
3695 // linkage, including function templates and function
3696 // template-ids but excluding non-static class members,
3697 // expressed as & id-expression where the & is optional if
3698 // the name refers to a function or array, or if the
3699 // corresponding template-parameter is a reference; or
3701 // In C++98/03 mode, give an extension warning on any extra parentheses.
3702 // See http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_defects.html#773
3703 bool ExtraParens = false;
3704 while (ParenExpr *Parens = dyn_cast<ParenExpr>(Arg)) {
3705 if (!Invalid && !ExtraParens) {
3706 S.Diag(Arg->getLocStart(),
3707 S.getLangOpts().CPlusPlus11 ?
3708 diag::warn_cxx98_compat_template_arg_extra_parens :
3709 diag::ext_template_arg_extra_parens)
3710 << Arg->getSourceRange();
3714 Arg = Parens->getSubExpr();
3717 while (SubstNonTypeTemplateParmExpr *subst =
3718 dyn_cast<SubstNonTypeTemplateParmExpr>(Arg))
3719 Arg = subst->getReplacement()->IgnoreImpCasts();
3721 bool AddressTaken = false;
3722 SourceLocation AddrOpLoc;
3723 if (UnaryOperator *UnOp = dyn_cast<UnaryOperator>(Arg)) {
3724 if (UnOp->getOpcode() == UO_AddrOf) {
3725 Arg = UnOp->getSubExpr();
3726 AddressTaken = true;
3727 AddrOpLoc = UnOp->getOperatorLoc();
3731 if (S.getLangOpts().MicrosoftExt && isa<CXXUuidofExpr>(Arg)) {
3732 Converted = TemplateArgument(ArgIn);
3736 while (SubstNonTypeTemplateParmExpr *subst =
3737 dyn_cast<SubstNonTypeTemplateParmExpr>(Arg))
3738 Arg = subst->getReplacement()->IgnoreImpCasts();
3740 // Stop checking the precise nature of the argument if it is value dependent,
3741 // it should be checked when instantiated.
3742 if (Arg->isValueDependent()) {
3743 Converted = TemplateArgument(ArgIn);
3747 DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Arg);
3749 S.Diag(Arg->getLocStart(), diag::err_template_arg_not_decl_ref)
3750 << Arg->getSourceRange();
3751 S.Diag(Param->getLocation(), diag::note_template_param_here);
3755 if (!isa<ValueDecl>(DRE->getDecl())) {
3756 S.Diag(Arg->getLocStart(),
3757 diag::err_template_arg_not_object_or_func_form)
3758 << Arg->getSourceRange();
3759 S.Diag(Param->getLocation(), diag::note_template_param_here);
3763 ValueDecl *Entity = DRE->getDecl();
3765 // Cannot refer to non-static data members
3766 if (FieldDecl *Field = dyn_cast<FieldDecl>(Entity)) {
3767 S.Diag(Arg->getLocStart(), diag::err_template_arg_field)
3768 << Field << Arg->getSourceRange();
3769 S.Diag(Param->getLocation(), diag::note_template_param_here);
3773 // Cannot refer to non-static member functions
3774 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Entity)) {
3775 if (!Method->isStatic()) {
3776 S.Diag(Arg->getLocStart(), diag::err_template_arg_method)
3777 << Method << Arg->getSourceRange();
3778 S.Diag(Param->getLocation(), diag::note_template_param_here);
3783 FunctionDecl *Func = dyn_cast<FunctionDecl>(Entity);
3784 VarDecl *Var = dyn_cast<VarDecl>(Entity);
3786 // A non-type template argument must refer to an object or function.
3787 if (!Func && !Var) {
3788 // We found something, but we don't know specifically what it is.
3789 S.Diag(Arg->getLocStart(), diag::err_template_arg_not_object_or_func)
3790 << Arg->getSourceRange();
3791 S.Diag(DRE->getDecl()->getLocation(), diag::note_template_arg_refers_here);
3795 // Address / reference template args must have external linkage in C++98.
3796 if (Entity->getLinkage() == InternalLinkage) {
3797 S.Diag(Arg->getLocStart(), S.getLangOpts().CPlusPlus11 ?
3798 diag::warn_cxx98_compat_template_arg_object_internal :
3799 diag::ext_template_arg_object_internal)
3800 << !Func << Entity << Arg->getSourceRange();
3801 S.Diag(Entity->getLocation(), diag::note_template_arg_internal_object)
3803 } else if (Entity->getLinkage() == NoLinkage) {
3804 S.Diag(Arg->getLocStart(), diag::err_template_arg_object_no_linkage)
3805 << !Func << Entity << Arg->getSourceRange();
3806 S.Diag(Entity->getLocation(), diag::note_template_arg_internal_object)
3812 // If the template parameter has pointer type, the function decays.
3813 if (ParamType->isPointerType() && !AddressTaken)
3814 ArgType = S.Context.getPointerType(Func->getType());
3815 else if (AddressTaken && ParamType->isReferenceType()) {
3816 // If we originally had an address-of operator, but the
3817 // parameter has reference type, complain and (if things look
3818 // like they will work) drop the address-of operator.
3819 if (!S.Context.hasSameUnqualifiedType(Func->getType(),
3820 ParamType.getNonReferenceType())) {
3821 S.Diag(AddrOpLoc, diag::err_template_arg_address_of_non_pointer)
3823 S.Diag(Param->getLocation(), diag::note_template_param_here);
3827 S.Diag(AddrOpLoc, diag::err_template_arg_address_of_non_pointer)
3829 << FixItHint::CreateRemoval(AddrOpLoc);
3830 S.Diag(Param->getLocation(), diag::note_template_param_here);
3832 ArgType = Func->getType();
3835 // A value of reference type is not an object.
3836 if (Var->getType()->isReferenceType()) {
3837 S.Diag(Arg->getLocStart(),
3838 diag::err_template_arg_reference_var)
3839 << Var->getType() << Arg->getSourceRange();
3840 S.Diag(Param->getLocation(), diag::note_template_param_here);
3844 // A template argument must have static storage duration.
3845 if (Var->getTLSKind()) {
3846 S.Diag(Arg->getLocStart(), diag::err_template_arg_thread_local)
3847 << Arg->getSourceRange();
3848 S.Diag(Var->getLocation(), diag::note_template_arg_refers_here);
3852 // If the template parameter has pointer type, we must have taken
3853 // the address of this object.
3854 if (ParamType->isReferenceType()) {
3856 // If we originally had an address-of operator, but the
3857 // parameter has reference type, complain and (if things look
3858 // like they will work) drop the address-of operator.
3859 if (!S.Context.hasSameUnqualifiedType(Var->getType(),
3860 ParamType.getNonReferenceType())) {
3861 S.Diag(AddrOpLoc, diag::err_template_arg_address_of_non_pointer)
3863 S.Diag(Param->getLocation(), diag::note_template_param_here);
3867 S.Diag(AddrOpLoc, diag::err_template_arg_address_of_non_pointer)
3869 << FixItHint::CreateRemoval(AddrOpLoc);
3870 S.Diag(Param->getLocation(), diag::note_template_param_here);
3872 ArgType = Var->getType();
3874 } else if (!AddressTaken && ParamType->isPointerType()) {
3875 if (Var->getType()->isArrayType()) {
3876 // Array-to-pointer decay.
3877 ArgType = S.Context.getArrayDecayedType(Var->getType());
3879 // If the template parameter has pointer type but the address of
3880 // this object was not taken, complain and (possibly) recover by
3881 // taking the address of the entity.
3882 ArgType = S.Context.getPointerType(Var->getType());
3883 if (!S.Context.hasSameUnqualifiedType(ArgType, ParamType)) {
3884 S.Diag(Arg->getLocStart(), diag::err_template_arg_not_address_of)
3886 S.Diag(Param->getLocation(), diag::note_template_param_here);
3890 S.Diag(Arg->getLocStart(), diag::err_template_arg_not_address_of)
3892 << FixItHint::CreateInsertion(Arg->getLocStart(), "&");
3894 S.Diag(Param->getLocation(), diag::note_template_param_here);
3899 bool ObjCLifetimeConversion;
3900 if (ParamType->isPointerType() &&
3901 !ParamType->getAs<PointerType>()->getPointeeType()->isFunctionType() &&
3902 S.IsQualificationConversion(ArgType, ParamType, false,
3903 ObjCLifetimeConversion)) {
3904 // For pointer-to-object types, qualification conversions are
3907 if (const ReferenceType *ParamRef = ParamType->getAs<ReferenceType>()) {
3908 if (!ParamRef->getPointeeType()->isFunctionType()) {
3909 // C++ [temp.arg.nontype]p5b3:
3910 // For a non-type template-parameter of type reference to
3911 // object, no conversions apply. The type referred to by the
3912 // reference may be more cv-qualified than the (otherwise
3913 // identical) type of the template- argument. The
3914 // template-parameter is bound directly to the
3915 // template-argument, which shall be an lvalue.
3917 // FIXME: Other qualifiers?
3918 unsigned ParamQuals = ParamRef->getPointeeType().getCVRQualifiers();
3919 unsigned ArgQuals = ArgType.getCVRQualifiers();
3921 if ((ParamQuals | ArgQuals) != ParamQuals) {
3922 S.Diag(Arg->getLocStart(),
3923 diag::err_template_arg_ref_bind_ignores_quals)
3924 << ParamType << Arg->getType()
3925 << Arg->getSourceRange();
3926 S.Diag(Param->getLocation(), diag::note_template_param_here);
3932 // At this point, the template argument refers to an object or
3933 // function with external linkage. We now need to check whether the
3934 // argument and parameter types are compatible.
3935 if (!S.Context.hasSameUnqualifiedType(ArgType,
3936 ParamType.getNonReferenceType())) {
3937 // We can't perform this conversion or binding.
3938 if (ParamType->isReferenceType())
3939 S.Diag(Arg->getLocStart(), diag::err_template_arg_no_ref_bind)
3940 << ParamType << ArgIn->getType() << Arg->getSourceRange();
3942 S.Diag(Arg->getLocStart(), diag::err_template_arg_not_convertible)
3943 << ArgIn->getType() << ParamType << Arg->getSourceRange();
3944 S.Diag(Param->getLocation(), diag::note_template_param_here);
3949 // Create the template argument.
3950 Converted = TemplateArgument(cast<ValueDecl>(Entity->getCanonicalDecl()),
3951 ParamType->isReferenceType());
3952 S.MarkAnyDeclReferenced(Arg->getLocStart(), Entity, false);
3956 /// \brief Checks whether the given template argument is a pointer to
3957 /// member constant according to C++ [temp.arg.nontype]p1.
3958 static bool CheckTemplateArgumentPointerToMember(Sema &S,
3959 NonTypeTemplateParmDecl *Param,
3962 TemplateArgument &Converted) {
3963 bool Invalid = false;
3965 // Check for a null pointer value.
3966 Expr *Arg = ResultArg;
3967 switch (isNullPointerValueTemplateArgument(S, Param, ParamType, Arg)) {
3970 case NPV_NullPointer:
3971 S.Diag(Arg->getExprLoc(), diag::warn_cxx98_compat_template_arg_null);
3972 Converted = TemplateArgument(ParamType, /*isNullPtr*/true);
3974 case NPV_NotNullPointer:
3978 bool ObjCLifetimeConversion;
3979 if (S.IsQualificationConversion(Arg->getType(),
3980 ParamType.getNonReferenceType(),
3981 false, ObjCLifetimeConversion)) {
3982 Arg = S.ImpCastExprToType(Arg, ParamType, CK_NoOp,
3983 Arg->getValueKind()).take();
3985 } else if (!S.Context.hasSameUnqualifiedType(Arg->getType(),
3986 ParamType.getNonReferenceType())) {
3987 // We can't perform this conversion.
3988 S.Diag(Arg->getLocStart(), diag::err_template_arg_not_convertible)
3989 << Arg->getType() << ParamType << Arg->getSourceRange();
3990 S.Diag(Param->getLocation(), diag::note_template_param_here);
3994 // See through any implicit casts we added to fix the type.
3995 while (ImplicitCastExpr *Cast = dyn_cast<ImplicitCastExpr>(Arg))
3996 Arg = Cast->getSubExpr();
3998 // C++ [temp.arg.nontype]p1:
4000 // A template-argument for a non-type, non-template
4001 // template-parameter shall be one of: [...]
4003 // -- a pointer to member expressed as described in 5.3.1.
4004 DeclRefExpr *DRE = 0;
4006 // In C++98/03 mode, give an extension warning on any extra parentheses.
4007 // See http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_defects.html#773
4008 bool ExtraParens = false;
4009 while (ParenExpr *Parens = dyn_cast<ParenExpr>(Arg)) {
4010 if (!Invalid && !ExtraParens) {
4011 S.Diag(Arg->getLocStart(),
4012 S.getLangOpts().CPlusPlus11 ?
4013 diag::warn_cxx98_compat_template_arg_extra_parens :
4014 diag::ext_template_arg_extra_parens)
4015 << Arg->getSourceRange();
4019 Arg = Parens->getSubExpr();
4022 while (SubstNonTypeTemplateParmExpr *subst =
4023 dyn_cast<SubstNonTypeTemplateParmExpr>(Arg))
4024 Arg = subst->getReplacement()->IgnoreImpCasts();
4026 // A pointer-to-member constant written &Class::member.
4027 if (UnaryOperator *UnOp = dyn_cast<UnaryOperator>(Arg)) {
4028 if (UnOp->getOpcode() == UO_AddrOf) {
4029 DRE = dyn_cast<DeclRefExpr>(UnOp->getSubExpr());
4030 if (DRE && !DRE->getQualifier())
4034 // A constant of pointer-to-member type.
4035 else if ((DRE = dyn_cast<DeclRefExpr>(Arg))) {
4036 if (ValueDecl *VD = dyn_cast<ValueDecl>(DRE->getDecl())) {
4037 if (VD->getType()->isMemberPointerType()) {
4038 if (isa<NonTypeTemplateParmDecl>(VD) ||
4039 (isa<VarDecl>(VD) &&
4040 S.Context.getCanonicalType(VD->getType()).isConstQualified())) {
4041 if (Arg->isTypeDependent() || Arg->isValueDependent()) {
4042 Converted = TemplateArgument(Arg);
4044 VD = cast<ValueDecl>(VD->getCanonicalDecl());
4045 Converted = TemplateArgument(VD, /*isReferenceParam*/false);
4056 return S.Diag(Arg->getLocStart(),
4057 diag::err_template_arg_not_pointer_to_member_form)
4058 << Arg->getSourceRange();
4060 if (isa<FieldDecl>(DRE->getDecl()) || isa<CXXMethodDecl>(DRE->getDecl())) {
4061 assert((isa<FieldDecl>(DRE->getDecl()) ||
4062 !cast<CXXMethodDecl>(DRE->getDecl())->isStatic()) &&
4063 "Only non-static member pointers can make it here");
4065 // Okay: this is the address of a non-static member, and therefore
4066 // a member pointer constant.
4067 if (Arg->isTypeDependent() || Arg->isValueDependent()) {
4068 Converted = TemplateArgument(Arg);
4070 ValueDecl *D = cast<ValueDecl>(DRE->getDecl()->getCanonicalDecl());
4071 Converted = TemplateArgument(D, /*isReferenceParam*/false);
4076 // We found something else, but we don't know specifically what it is.
4077 S.Diag(Arg->getLocStart(),
4078 diag::err_template_arg_not_pointer_to_member_form)
4079 << Arg->getSourceRange();
4080 S.Diag(DRE->getDecl()->getLocation(), diag::note_template_arg_refers_here);
4084 /// \brief Check a template argument against its corresponding
4085 /// non-type template parameter.
4087 /// This routine implements the semantics of C++ [temp.arg.nontype].
4088 /// If an error occurred, it returns ExprError(); otherwise, it
4089 /// returns the converted template argument. \p
4090 /// InstantiatedParamType is the type of the non-type template
4091 /// parameter after it has been instantiated.
4092 ExprResult Sema::CheckTemplateArgument(NonTypeTemplateParmDecl *Param,
4093 QualType InstantiatedParamType, Expr *Arg,
4094 TemplateArgument &Converted,
4095 CheckTemplateArgumentKind CTAK) {
4096 SourceLocation StartLoc = Arg->getLocStart();
4098 // If either the parameter has a dependent type or the argument is
4099 // type-dependent, there's nothing we can check now.
4100 if (InstantiatedParamType->isDependentType() || Arg->isTypeDependent()) {
4101 // FIXME: Produce a cloned, canonical expression?
4102 Converted = TemplateArgument(Arg);
4106 // C++ [temp.arg.nontype]p5:
4107 // The following conversions are performed on each expression used
4108 // as a non-type template-argument. If a non-type
4109 // template-argument cannot be converted to the type of the
4110 // corresponding template-parameter then the program is
4112 QualType ParamType = InstantiatedParamType;
4113 if (ParamType->isIntegralOrEnumerationType()) {
4115 // -- for a non-type template-parameter of integral or
4116 // enumeration type, conversions permitted in a converted
4117 // constant expression are applied.
4120 // -- for a non-type template-parameter of integral or
4121 // enumeration type, integral promotions (4.5) and integral
4122 // conversions (4.7) are applied.
4124 if (CTAK == CTAK_Deduced &&
4125 !Context.hasSameUnqualifiedType(ParamType, Arg->getType())) {
4126 // C++ [temp.deduct.type]p17:
4127 // If, in the declaration of a function template with a non-type
4128 // template-parameter, the non-type template-parameter is used
4129 // in an expression in the function parameter-list and, if the
4130 // corresponding template-argument is deduced, the
4131 // template-argument type shall match the type of the
4132 // template-parameter exactly, except that a template-argument
4133 // deduced from an array bound may be of any integral type.
4134 Diag(StartLoc, diag::err_deduced_non_type_template_arg_type_mismatch)
4135 << Arg->getType().getUnqualifiedType()
4136 << ParamType.getUnqualifiedType();
4137 Diag(Param->getLocation(), diag::note_template_param_here);
4141 if (getLangOpts().CPlusPlus11) {
4142 // We can't check arbitrary value-dependent arguments.
4143 // FIXME: If there's no viable conversion to the template parameter type,
4144 // we should be able to diagnose that prior to instantiation.
4145 if (Arg->isValueDependent()) {
4146 Converted = TemplateArgument(Arg);
4150 // C++ [temp.arg.nontype]p1:
4151 // A template-argument for a non-type, non-template template-parameter
4154 // -- for a non-type template-parameter of integral or enumeration
4155 // type, a converted constant expression of the type of the
4156 // template-parameter; or
4158 ExprResult ArgResult =
4159 CheckConvertedConstantExpression(Arg, ParamType, Value,
4161 if (ArgResult.isInvalid())
4164 // Widen the argument value to sizeof(parameter type). This is almost
4165 // always a no-op, except when the parameter type is bool. In
4166 // that case, this may extend the argument from 1 bit to 8 bits.
4167 QualType IntegerType = ParamType;
4168 if (const EnumType *Enum = IntegerType->getAs<EnumType>())
4169 IntegerType = Enum->getDecl()->getIntegerType();
4170 Value = Value.extOrTrunc(Context.getTypeSize(IntegerType));
4172 Converted = TemplateArgument(Context, Value,
4173 Context.getCanonicalType(ParamType));
4177 ExprResult ArgResult = DefaultLvalueConversion(Arg);
4178 if (ArgResult.isInvalid())
4180 Arg = ArgResult.take();
4182 QualType ArgType = Arg->getType();
4184 // C++ [temp.arg.nontype]p1:
4185 // A template-argument for a non-type, non-template
4186 // template-parameter shall be one of:
4188 // -- an integral constant-expression of integral or enumeration
4190 // -- the name of a non-type template-parameter; or
4191 SourceLocation NonConstantLoc;
4193 if (!ArgType->isIntegralOrEnumerationType()) {
4194 Diag(Arg->getLocStart(),
4195 diag::err_template_arg_not_integral_or_enumeral)
4196 << ArgType << Arg->getSourceRange();
4197 Diag(Param->getLocation(), diag::note_template_param_here);
4199 } else if (!Arg->isValueDependent()) {
4200 class TmplArgICEDiagnoser : public VerifyICEDiagnoser {
4204 TmplArgICEDiagnoser(QualType T) : T(T) { }
4206 virtual void diagnoseNotICE(Sema &S, SourceLocation Loc,
4208 S.Diag(Loc, diag::err_template_arg_not_ice) << T << SR;
4210 } Diagnoser(ArgType);
4212 Arg = VerifyIntegerConstantExpression(Arg, &Value, Diagnoser,
4218 // From here on out, all we care about are the unqualified forms
4219 // of the parameter and argument types.
4220 ParamType = ParamType.getUnqualifiedType();
4221 ArgType = ArgType.getUnqualifiedType();
4223 // Try to convert the argument to the parameter's type.
4224 if (Context.hasSameType(ParamType, ArgType)) {
4225 // Okay: no conversion necessary
4226 } else if (ParamType->isBooleanType()) {
4227 // This is an integral-to-boolean conversion.
4228 Arg = ImpCastExprToType(Arg, ParamType, CK_IntegralToBoolean).take();
4229 } else if (IsIntegralPromotion(Arg, ArgType, ParamType) ||
4230 !ParamType->isEnumeralType()) {
4231 // This is an integral promotion or conversion.
4232 Arg = ImpCastExprToType(Arg, ParamType, CK_IntegralCast).take();
4234 // We can't perform this conversion.
4235 Diag(Arg->getLocStart(),
4236 diag::err_template_arg_not_convertible)
4237 << Arg->getType() << InstantiatedParamType << Arg->getSourceRange();
4238 Diag(Param->getLocation(), diag::note_template_param_here);
4242 // Add the value of this argument to the list of converted
4243 // arguments. We use the bitwidth and signedness of the template
4245 if (Arg->isValueDependent()) {
4246 // The argument is value-dependent. Create a new
4247 // TemplateArgument with the converted expression.
4248 Converted = TemplateArgument(Arg);
4252 QualType IntegerType = Context.getCanonicalType(ParamType);
4253 if (const EnumType *Enum = IntegerType->getAs<EnumType>())
4254 IntegerType = Context.getCanonicalType(Enum->getDecl()->getIntegerType());
4256 if (ParamType->isBooleanType()) {
4257 // Value must be zero or one.
4259 unsigned AllowedBits = Context.getTypeSize(IntegerType);
4260 if (Value.getBitWidth() != AllowedBits)
4261 Value = Value.extOrTrunc(AllowedBits);
4262 Value.setIsSigned(IntegerType->isSignedIntegerOrEnumerationType());
4264 llvm::APSInt OldValue = Value;
4266 // Coerce the template argument's value to the value it will have
4267 // based on the template parameter's type.
4268 unsigned AllowedBits = Context.getTypeSize(IntegerType);
4269 if (Value.getBitWidth() != AllowedBits)
4270 Value = Value.extOrTrunc(AllowedBits);
4271 Value.setIsSigned(IntegerType->isSignedIntegerOrEnumerationType());
4273 // Complain if an unsigned parameter received a negative value.
4274 if (IntegerType->isUnsignedIntegerOrEnumerationType()
4275 && (OldValue.isSigned() && OldValue.isNegative())) {
4276 Diag(Arg->getLocStart(), diag::warn_template_arg_negative)
4277 << OldValue.toString(10) << Value.toString(10) << Param->getType()
4278 << Arg->getSourceRange();
4279 Diag(Param->getLocation(), diag::note_template_param_here);
4282 // Complain if we overflowed the template parameter's type.
4283 unsigned RequiredBits;
4284 if (IntegerType->isUnsignedIntegerOrEnumerationType())
4285 RequiredBits = OldValue.getActiveBits();
4286 else if (OldValue.isUnsigned())
4287 RequiredBits = OldValue.getActiveBits() + 1;
4289 RequiredBits = OldValue.getMinSignedBits();
4290 if (RequiredBits > AllowedBits) {
4291 Diag(Arg->getLocStart(),
4292 diag::warn_template_arg_too_large)
4293 << OldValue.toString(10) << Value.toString(10) << Param->getType()
4294 << Arg->getSourceRange();
4295 Diag(Param->getLocation(), diag::note_template_param_here);
4299 Converted = TemplateArgument(Context, Value,
4300 ParamType->isEnumeralType()
4301 ? Context.getCanonicalType(ParamType)
4306 QualType ArgType = Arg->getType();
4307 DeclAccessPair FoundResult; // temporary for ResolveOverloadedFunction
4309 // Handle pointer-to-function, reference-to-function, and
4310 // pointer-to-member-function all in (roughly) the same way.
4311 if (// -- For a non-type template-parameter of type pointer to
4312 // function, only the function-to-pointer conversion (4.3) is
4313 // applied. If the template-argument represents a set of
4314 // overloaded functions (or a pointer to such), the matching
4315 // function is selected from the set (13.4).
4316 (ParamType->isPointerType() &&
4317 ParamType->getAs<PointerType>()->getPointeeType()->isFunctionType()) ||
4318 // -- For a non-type template-parameter of type reference to
4319 // function, no conversions apply. If the template-argument
4320 // represents a set of overloaded functions, the matching
4321 // function is selected from the set (13.4).
4322 (ParamType->isReferenceType() &&
4323 ParamType->getAs<ReferenceType>()->getPointeeType()->isFunctionType()) ||
4324 // -- For a non-type template-parameter of type pointer to
4325 // member function, no conversions apply. If the
4326 // template-argument represents a set of overloaded member
4327 // functions, the matching member function is selected from
4329 (ParamType->isMemberPointerType() &&
4330 ParamType->getAs<MemberPointerType>()->getPointeeType()
4331 ->isFunctionType())) {
4333 if (Arg->getType() == Context.OverloadTy) {
4334 if (FunctionDecl *Fn = ResolveAddressOfOverloadedFunction(Arg, ParamType,
4337 if (DiagnoseUseOfDecl(Fn, Arg->getLocStart()))
4340 Arg = FixOverloadedFunctionReference(Arg, FoundResult, Fn);
4341 ArgType = Arg->getType();
4346 if (!ParamType->isMemberPointerType()) {
4347 if (CheckTemplateArgumentAddressOfObjectOrFunction(*this, Param,
4354 if (CheckTemplateArgumentPointerToMember(*this, Param, ParamType, Arg,
4360 if (ParamType->isPointerType()) {
4361 // -- for a non-type template-parameter of type pointer to
4362 // object, qualification conversions (4.4) and the
4363 // array-to-pointer conversion (4.2) are applied.
4364 // C++0x also allows a value of std::nullptr_t.
4365 assert(ParamType->getPointeeType()->isIncompleteOrObjectType() &&
4366 "Only object pointers allowed here");
4368 if (CheckTemplateArgumentAddressOfObjectOrFunction(*this, Param,
4375 if (const ReferenceType *ParamRefType = ParamType->getAs<ReferenceType>()) {
4376 // -- For a non-type template-parameter of type reference to
4377 // object, no conversions apply. The type referred to by the
4378 // reference may be more cv-qualified than the (otherwise
4379 // identical) type of the template-argument. The
4380 // template-parameter is bound directly to the
4381 // template-argument, which must be an lvalue.
4382 assert(ParamRefType->getPointeeType()->isIncompleteOrObjectType() &&
4383 "Only object references allowed here");
4385 if (Arg->getType() == Context.OverloadTy) {
4386 if (FunctionDecl *Fn = ResolveAddressOfOverloadedFunction(Arg,
4387 ParamRefType->getPointeeType(),
4390 if (DiagnoseUseOfDecl(Fn, Arg->getLocStart()))
4393 Arg = FixOverloadedFunctionReference(Arg, FoundResult, Fn);
4394 ArgType = Arg->getType();
4399 if (CheckTemplateArgumentAddressOfObjectOrFunction(*this, Param,
4406 // Deal with parameters of type std::nullptr_t.
4407 if (ParamType->isNullPtrType()) {
4408 if (Arg->isTypeDependent() || Arg->isValueDependent()) {
4409 Converted = TemplateArgument(Arg);
4413 switch (isNullPointerValueTemplateArgument(*this, Param, ParamType, Arg)) {
4414 case NPV_NotNullPointer:
4415 Diag(Arg->getExprLoc(), diag::err_template_arg_not_convertible)
4416 << Arg->getType() << ParamType;
4417 Diag(Param->getLocation(), diag::note_template_param_here);
4423 case NPV_NullPointer:
4424 Diag(Arg->getExprLoc(), diag::warn_cxx98_compat_template_arg_null);
4425 Converted = TemplateArgument(ParamType, /*isNullPtr*/true);
4430 // -- For a non-type template-parameter of type pointer to data
4431 // member, qualification conversions (4.4) are applied.
4432 assert(ParamType->isMemberPointerType() && "Only pointers to members remain");
4434 if (CheckTemplateArgumentPointerToMember(*this, Param, ParamType, Arg,
4440 /// \brief Check a template argument against its corresponding
4441 /// template template parameter.
4443 /// This routine implements the semantics of C++ [temp.arg.template].
4444 /// It returns true if an error occurred, and false otherwise.
4445 bool Sema::CheckTemplateArgument(TemplateTemplateParmDecl *Param,
4446 const TemplateArgumentLoc &Arg,
4447 unsigned ArgumentPackIndex) {
4448 TemplateName Name = Arg.getArgument().getAsTemplateOrTemplatePattern();
4449 TemplateDecl *Template = Name.getAsTemplateDecl();
4451 // Any dependent template name is fine.
4452 assert(Name.isDependent() && "Non-dependent template isn't a declaration?");
4456 // C++0x [temp.arg.template]p1:
4457 // A template-argument for a template template-parameter shall be
4458 // the name of a class template or an alias template, expressed as an
4459 // id-expression. When the template-argument names a class template, only
4460 // primary class templates are considered when matching the
4461 // template template argument with the corresponding parameter;
4462 // partial specializations are not considered even if their
4463 // parameter lists match that of the template template parameter.
4465 // Note that we also allow template template parameters here, which
4466 // will happen when we are dealing with, e.g., class template
4467 // partial specializations.
4468 if (!isa<ClassTemplateDecl>(Template) &&
4469 !isa<TemplateTemplateParmDecl>(Template) &&
4470 !isa<TypeAliasTemplateDecl>(Template)) {
4471 assert(isa<FunctionTemplateDecl>(Template) &&
4472 "Only function templates are possible here");
4473 Diag(Arg.getLocation(), diag::err_template_arg_not_class_template);
4474 Diag(Template->getLocation(), diag::note_template_arg_refers_here_func)
4478 TemplateParameterList *Params = Param->getTemplateParameters();
4479 if (Param->isExpandedParameterPack())
4480 Params = Param->getExpansionTemplateParameters(ArgumentPackIndex);
4482 return !TemplateParameterListsAreEqual(Template->getTemplateParameters(),
4485 TPL_TemplateTemplateArgumentMatch,
4489 /// \brief Given a non-type template argument that refers to a
4490 /// declaration and the type of its corresponding non-type template
4491 /// parameter, produce an expression that properly refers to that
4494 Sema::BuildExpressionFromDeclTemplateArgument(const TemplateArgument &Arg,
4496 SourceLocation Loc) {
4497 // C++ [temp.param]p8:
4499 // A non-type template-parameter of type "array of T" or
4500 // "function returning T" is adjusted to be of type "pointer to
4501 // T" or "pointer to function returning T", respectively.
4502 if (ParamType->isArrayType())
4503 ParamType = Context.getArrayDecayedType(ParamType);
4504 else if (ParamType->isFunctionType())
4505 ParamType = Context.getPointerType(ParamType);
4507 // For a NULL non-type template argument, return nullptr casted to the
4508 // parameter's type.
4509 if (Arg.getKind() == TemplateArgument::NullPtr) {
4510 return ImpCastExprToType(
4511 new (Context) CXXNullPtrLiteralExpr(Context.NullPtrTy, Loc),
4513 ParamType->getAs<MemberPointerType>()
4514 ? CK_NullToMemberPointer
4515 : CK_NullToPointer);
4517 assert(Arg.getKind() == TemplateArgument::Declaration &&
4518 "Only declaration template arguments permitted here");
4520 ValueDecl *VD = cast<ValueDecl>(Arg.getAsDecl());
4522 if (VD->getDeclContext()->isRecord() &&
4523 (isa<CXXMethodDecl>(VD) || isa<FieldDecl>(VD))) {
4524 // If the value is a class member, we might have a pointer-to-member.
4525 // Determine whether the non-type template template parameter is of
4526 // pointer-to-member type. If so, we need to build an appropriate
4527 // expression for a pointer-to-member, since a "normal" DeclRefExpr
4528 // would refer to the member itself.
4529 if (ParamType->isMemberPointerType()) {
4531 = Context.getTypeDeclType(cast<RecordDecl>(VD->getDeclContext()));
4532 NestedNameSpecifier *Qualifier
4533 = NestedNameSpecifier::Create(Context, 0, false,
4534 ClassType.getTypePtr());
4536 SS.MakeTrivial(Context, Qualifier, Loc);
4538 // The actual value-ness of this is unimportant, but for
4539 // internal consistency's sake, references to instance methods
4541 ExprValueKind VK = VK_LValue;
4542 if (isa<CXXMethodDecl>(VD) && cast<CXXMethodDecl>(VD)->isInstance())
4545 ExprResult RefExpr = BuildDeclRefExpr(VD,
4546 VD->getType().getNonReferenceType(),
4550 if (RefExpr.isInvalid())
4553 RefExpr = CreateBuiltinUnaryOp(Loc, UO_AddrOf, RefExpr.get());
4555 // We might need to perform a trailing qualification conversion, since
4556 // the element type on the parameter could be more qualified than the
4557 // element type in the expression we constructed.
4558 bool ObjCLifetimeConversion;
4559 if (IsQualificationConversion(((Expr*) RefExpr.get())->getType(),
4560 ParamType.getUnqualifiedType(), false,
4561 ObjCLifetimeConversion))
4562 RefExpr = ImpCastExprToType(RefExpr.take(), ParamType.getUnqualifiedType(), CK_NoOp);
4564 assert(!RefExpr.isInvalid() &&
4565 Context.hasSameType(((Expr*) RefExpr.get())->getType(),
4566 ParamType.getUnqualifiedType()));
4571 QualType T = VD->getType().getNonReferenceType();
4573 if (ParamType->isPointerType()) {
4574 // When the non-type template parameter is a pointer, take the
4575 // address of the declaration.
4576 ExprResult RefExpr = BuildDeclRefExpr(VD, T, VK_LValue, Loc);
4577 if (RefExpr.isInvalid())
4580 if (T->isFunctionType() || T->isArrayType()) {
4581 // Decay functions and arrays.
4582 RefExpr = DefaultFunctionArrayConversion(RefExpr.take());
4583 if (RefExpr.isInvalid())
4589 // Take the address of everything else
4590 return CreateBuiltinUnaryOp(Loc, UO_AddrOf, RefExpr.get());
4593 ExprValueKind VK = VK_RValue;
4595 // If the non-type template parameter has reference type, qualify the
4596 // resulting declaration reference with the extra qualifiers on the
4597 // type that the reference refers to.
4598 if (const ReferenceType *TargetRef = ParamType->getAs<ReferenceType>()) {
4600 T = Context.getQualifiedType(T,
4601 TargetRef->getPointeeType().getQualifiers());
4602 } else if (isa<FunctionDecl>(VD)) {
4603 // References to functions are always lvalues.
4607 return BuildDeclRefExpr(VD, T, VK, Loc);
4610 /// \brief Construct a new expression that refers to the given
4611 /// integral template argument with the given source-location
4614 /// This routine takes care of the mapping from an integral template
4615 /// argument (which may have any integral type) to the appropriate
4618 Sema::BuildExpressionFromIntegralTemplateArgument(const TemplateArgument &Arg,
4619 SourceLocation Loc) {
4620 assert(Arg.getKind() == TemplateArgument::Integral &&
4621 "Operation is only valid for integral template arguments");
4622 QualType OrigT = Arg.getIntegralType();
4624 // If this is an enum type that we're instantiating, we need to use an integer
4625 // type the same size as the enumerator. We don't want to build an
4626 // IntegerLiteral with enum type. The integer type of an enum type can be of
4627 // any integral type with C++11 enum classes, make sure we create the right
4628 // type of literal for it.
4630 if (const EnumType *ET = OrigT->getAs<EnumType>())
4631 T = ET->getDecl()->getIntegerType();
4634 if (T->isAnyCharacterType()) {
4635 CharacterLiteral::CharacterKind Kind;
4636 if (T->isWideCharType())
4637 Kind = CharacterLiteral::Wide;
4638 else if (T->isChar16Type())
4639 Kind = CharacterLiteral::UTF16;
4640 else if (T->isChar32Type())
4641 Kind = CharacterLiteral::UTF32;
4643 Kind = CharacterLiteral::Ascii;
4645 E = new (Context) CharacterLiteral(Arg.getAsIntegral().getZExtValue(),
4647 } else if (T->isBooleanType()) {
4648 E = new (Context) CXXBoolLiteralExpr(Arg.getAsIntegral().getBoolValue(),
4650 } else if (T->isNullPtrType()) {
4651 E = new (Context) CXXNullPtrLiteralExpr(Context.NullPtrTy, Loc);
4653 E = IntegerLiteral::Create(Context, Arg.getAsIntegral(), T, Loc);
4656 if (OrigT->isEnumeralType()) {
4657 // FIXME: This is a hack. We need a better way to handle substituted
4658 // non-type template parameters.
4659 E = CStyleCastExpr::Create(Context, OrigT, VK_RValue, CK_IntegralCast, E, 0,
4660 Context.getTrivialTypeSourceInfo(OrigT, Loc),
4667 /// \brief Match two template parameters within template parameter lists.
4668 static bool MatchTemplateParameterKind(Sema &S, NamedDecl *New, NamedDecl *Old,
4670 Sema::TemplateParameterListEqualKind Kind,
4671 SourceLocation TemplateArgLoc) {
4672 // Check the actual kind (type, non-type, template).
4673 if (Old->getKind() != New->getKind()) {
4675 unsigned NextDiag = diag::err_template_param_different_kind;
4676 if (TemplateArgLoc.isValid()) {
4677 S.Diag(TemplateArgLoc, diag::err_template_arg_template_params_mismatch);
4678 NextDiag = diag::note_template_param_different_kind;
4680 S.Diag(New->getLocation(), NextDiag)
4681 << (Kind != Sema::TPL_TemplateMatch);
4682 S.Diag(Old->getLocation(), diag::note_template_prev_declaration)
4683 << (Kind != Sema::TPL_TemplateMatch);
4689 // Check that both are parameter packs are neither are parameter packs.
4690 // However, if we are matching a template template argument to a
4691 // template template parameter, the template template parameter can have
4692 // a parameter pack where the template template argument does not.
4693 if (Old->isTemplateParameterPack() != New->isTemplateParameterPack() &&
4694 !(Kind == Sema::TPL_TemplateTemplateArgumentMatch &&
4695 Old->isTemplateParameterPack())) {
4697 unsigned NextDiag = diag::err_template_parameter_pack_non_pack;
4698 if (TemplateArgLoc.isValid()) {
4699 S.Diag(TemplateArgLoc,
4700 diag::err_template_arg_template_params_mismatch);
4701 NextDiag = diag::note_template_parameter_pack_non_pack;
4704 unsigned ParamKind = isa<TemplateTypeParmDecl>(New)? 0
4705 : isa<NonTypeTemplateParmDecl>(New)? 1
4707 S.Diag(New->getLocation(), NextDiag)
4708 << ParamKind << New->isParameterPack();
4709 S.Diag(Old->getLocation(), diag::note_template_parameter_pack_here)
4710 << ParamKind << Old->isParameterPack();
4716 // For non-type template parameters, check the type of the parameter.
4717 if (NonTypeTemplateParmDecl *OldNTTP
4718 = dyn_cast<NonTypeTemplateParmDecl>(Old)) {
4719 NonTypeTemplateParmDecl *NewNTTP = cast<NonTypeTemplateParmDecl>(New);
4721 // If we are matching a template template argument to a template
4722 // template parameter and one of the non-type template parameter types
4723 // is dependent, then we must wait until template instantiation time
4724 // to actually compare the arguments.
4725 if (Kind == Sema::TPL_TemplateTemplateArgumentMatch &&
4726 (OldNTTP->getType()->isDependentType() ||
4727 NewNTTP->getType()->isDependentType()))
4730 if (!S.Context.hasSameType(OldNTTP->getType(), NewNTTP->getType())) {
4732 unsigned NextDiag = diag::err_template_nontype_parm_different_type;
4733 if (TemplateArgLoc.isValid()) {
4734 S.Diag(TemplateArgLoc,
4735 diag::err_template_arg_template_params_mismatch);
4736 NextDiag = diag::note_template_nontype_parm_different_type;
4738 S.Diag(NewNTTP->getLocation(), NextDiag)
4739 << NewNTTP->getType()
4740 << (Kind != Sema::TPL_TemplateMatch);
4741 S.Diag(OldNTTP->getLocation(),
4742 diag::note_template_nontype_parm_prev_declaration)
4743 << OldNTTP->getType();
4752 // For template template parameters, check the template parameter types.
4753 // The template parameter lists of template template
4754 // parameters must agree.
4755 if (TemplateTemplateParmDecl *OldTTP
4756 = dyn_cast<TemplateTemplateParmDecl>(Old)) {
4757 TemplateTemplateParmDecl *NewTTP = cast<TemplateTemplateParmDecl>(New);
4758 return S.TemplateParameterListsAreEqual(NewTTP->getTemplateParameters(),
4759 OldTTP->getTemplateParameters(),
4761 (Kind == Sema::TPL_TemplateMatch
4762 ? Sema::TPL_TemplateTemplateParmMatch
4770 /// \brief Diagnose a known arity mismatch when comparing template argument
4773 void DiagnoseTemplateParameterListArityMismatch(Sema &S,
4774 TemplateParameterList *New,
4775 TemplateParameterList *Old,
4776 Sema::TemplateParameterListEqualKind Kind,
4777 SourceLocation TemplateArgLoc) {
4778 unsigned NextDiag = diag::err_template_param_list_different_arity;
4779 if (TemplateArgLoc.isValid()) {
4780 S.Diag(TemplateArgLoc, diag::err_template_arg_template_params_mismatch);
4781 NextDiag = diag::note_template_param_list_different_arity;
4783 S.Diag(New->getTemplateLoc(), NextDiag)
4784 << (New->size() > Old->size())
4785 << (Kind != Sema::TPL_TemplateMatch)
4786 << SourceRange(New->getTemplateLoc(), New->getRAngleLoc());
4787 S.Diag(Old->getTemplateLoc(), diag::note_template_prev_declaration)
4788 << (Kind != Sema::TPL_TemplateMatch)
4789 << SourceRange(Old->getTemplateLoc(), Old->getRAngleLoc());
4792 /// \brief Determine whether the given template parameter lists are
4795 /// \param New The new template parameter list, typically written in the
4796 /// source code as part of a new template declaration.
4798 /// \param Old The old template parameter list, typically found via
4799 /// name lookup of the template declared with this template parameter
4802 /// \param Complain If true, this routine will produce a diagnostic if
4803 /// the template parameter lists are not equivalent.
4805 /// \param Kind describes how we are to match the template parameter lists.
4807 /// \param TemplateArgLoc If this source location is valid, then we
4808 /// are actually checking the template parameter list of a template
4809 /// argument (New) against the template parameter list of its
4810 /// corresponding template template parameter (Old). We produce
4811 /// slightly different diagnostics in this scenario.
4813 /// \returns True if the template parameter lists are equal, false
4816 Sema::TemplateParameterListsAreEqual(TemplateParameterList *New,
4817 TemplateParameterList *Old,
4819 TemplateParameterListEqualKind Kind,
4820 SourceLocation TemplateArgLoc) {
4821 if (Old->size() != New->size() && Kind != TPL_TemplateTemplateArgumentMatch) {
4823 DiagnoseTemplateParameterListArityMismatch(*this, New, Old, Kind,
4829 // C++0x [temp.arg.template]p3:
4830 // A template-argument matches a template template-parameter (call it P)
4831 // when each of the template parameters in the template-parameter-list of
4832 // the template-argument's corresponding class template or alias template
4833 // (call it A) matches the corresponding template parameter in the
4834 // template-parameter-list of P. [...]
4835 TemplateParameterList::iterator NewParm = New->begin();
4836 TemplateParameterList::iterator NewParmEnd = New->end();
4837 for (TemplateParameterList::iterator OldParm = Old->begin(),
4838 OldParmEnd = Old->end();
4839 OldParm != OldParmEnd; ++OldParm) {
4840 if (Kind != TPL_TemplateTemplateArgumentMatch ||
4841 !(*OldParm)->isTemplateParameterPack()) {
4842 if (NewParm == NewParmEnd) {
4844 DiagnoseTemplateParameterListArityMismatch(*this, New, Old, Kind,
4850 if (!MatchTemplateParameterKind(*this, *NewParm, *OldParm, Complain,
4851 Kind, TemplateArgLoc))
4858 // C++0x [temp.arg.template]p3:
4859 // [...] When P's template- parameter-list contains a template parameter
4860 // pack (14.5.3), the template parameter pack will match zero or more
4861 // template parameters or template parameter packs in the
4862 // template-parameter-list of A with the same type and form as the
4863 // template parameter pack in P (ignoring whether those template
4864 // parameters are template parameter packs).
4865 for (; NewParm != NewParmEnd; ++NewParm) {
4866 if (!MatchTemplateParameterKind(*this, *NewParm, *OldParm, Complain,
4867 Kind, TemplateArgLoc))
4872 // Make sure we exhausted all of the arguments.
4873 if (NewParm != NewParmEnd) {
4875 DiagnoseTemplateParameterListArityMismatch(*this, New, Old, Kind,
4884 /// \brief Check whether a template can be declared within this scope.
4886 /// If the template declaration is valid in this scope, returns
4887 /// false. Otherwise, issues a diagnostic and returns true.
4889 Sema::CheckTemplateDeclScope(Scope *S, TemplateParameterList *TemplateParams) {
4893 // Find the nearest enclosing declaration scope.
4894 while ((S->getFlags() & Scope::DeclScope) == 0 ||
4895 (S->getFlags() & Scope::TemplateParamScope) != 0)
4899 // A template-declaration can appear only as a namespace scope or
4900 // class scope declaration.
4901 DeclContext *Ctx = static_cast<DeclContext *>(S->getEntity());
4902 if (Ctx && isa<LinkageSpecDecl>(Ctx) &&
4903 cast<LinkageSpecDecl>(Ctx)->getLanguage() != LinkageSpecDecl::lang_cxx)
4904 return Diag(TemplateParams->getTemplateLoc(), diag::err_template_linkage)
4905 << TemplateParams->getSourceRange();
4907 while (Ctx && isa<LinkageSpecDecl>(Ctx))
4908 Ctx = Ctx->getParent();
4910 if (Ctx && (Ctx->isFileContext() || Ctx->isRecord()))
4913 return Diag(TemplateParams->getTemplateLoc(),
4914 diag::err_template_outside_namespace_or_class_scope)
4915 << TemplateParams->getSourceRange();
4918 /// \brief Determine what kind of template specialization the given declaration
4920 static TemplateSpecializationKind getTemplateSpecializationKind(Decl *D) {
4922 return TSK_Undeclared;
4924 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(D))
4925 return Record->getTemplateSpecializationKind();
4926 if (FunctionDecl *Function = dyn_cast<FunctionDecl>(D))
4927 return Function->getTemplateSpecializationKind();
4928 if (VarDecl *Var = dyn_cast<VarDecl>(D))
4929 return Var->getTemplateSpecializationKind();
4931 return TSK_Undeclared;
4934 /// \brief Check whether a specialization is well-formed in the current
4937 /// This routine determines whether a template specialization can be declared
4938 /// in the current context (C++ [temp.expl.spec]p2).
4940 /// \param S the semantic analysis object for which this check is being
4943 /// \param Specialized the entity being specialized or instantiated, which
4944 /// may be a kind of template (class template, function template, etc.) or
4945 /// a member of a class template (member function, static data member,
4948 /// \param PrevDecl the previous declaration of this entity, if any.
4950 /// \param Loc the location of the explicit specialization or instantiation of
4953 /// \param IsPartialSpecialization whether this is a partial specialization of
4954 /// a class template.
4956 /// \returns true if there was an error that we cannot recover from, false
4958 static bool CheckTemplateSpecializationScope(Sema &S,
4959 NamedDecl *Specialized,
4960 NamedDecl *PrevDecl,
4962 bool IsPartialSpecialization) {
4963 // Keep these "kind" numbers in sync with the %select statements in the
4964 // various diagnostics emitted by this routine.
4966 if (isa<ClassTemplateDecl>(Specialized))
4967 EntityKind = IsPartialSpecialization? 1 : 0;
4968 else if (isa<FunctionTemplateDecl>(Specialized))
4970 else if (isa<CXXMethodDecl>(Specialized))
4972 else if (isa<VarDecl>(Specialized))
4974 else if (isa<RecordDecl>(Specialized))
4976 else if (isa<EnumDecl>(Specialized) && S.getLangOpts().CPlusPlus11)
4979 S.Diag(Loc, diag::err_template_spec_unknown_kind)
4980 << S.getLangOpts().CPlusPlus11;
4981 S.Diag(Specialized->getLocation(), diag::note_specialized_entity);
4985 // C++ [temp.expl.spec]p2:
4986 // An explicit specialization shall be declared in the namespace
4987 // of which the template is a member, or, for member templates, in
4988 // the namespace of which the enclosing class or enclosing class
4989 // template is a member. An explicit specialization of a member
4990 // function, member class or static data member of a class
4991 // template shall be declared in the namespace of which the class
4992 // template is a member. Such a declaration may also be a
4993 // definition. If the declaration is not a definition, the
4994 // specialization may be defined later in the name- space in which
4995 // the explicit specialization was declared, or in a namespace
4996 // that encloses the one in which the explicit specialization was
4998 if (S.CurContext->getRedeclContext()->isFunctionOrMethod()) {
4999 S.Diag(Loc, diag::err_template_spec_decl_function_scope)
5004 if (S.CurContext->isRecord() && !IsPartialSpecialization) {
5005 if (S.getLangOpts().MicrosoftExt) {
5006 // Do not warn for class scope explicit specialization during
5007 // instantiation, warning was already emitted during pattern
5008 // semantic analysis.
5009 if (!S.ActiveTemplateInstantiations.size())
5010 S.Diag(Loc, diag::ext_function_specialization_in_class)
5013 S.Diag(Loc, diag::err_template_spec_decl_class_scope)
5019 if (S.CurContext->isRecord() &&
5020 !S.CurContext->Equals(Specialized->getDeclContext())) {
5021 // Make sure that we're specializing in the right record context.
5022 // Otherwise, things can go horribly wrong.
5023 S.Diag(Loc, diag::err_template_spec_decl_class_scope)
5028 // C++ [temp.class.spec]p6:
5029 // A class template partial specialization may be declared or redeclared
5030 // in any namespace scope in which its definition may be defined (14.5.1
5032 bool ComplainedAboutScope = false;
5033 DeclContext *SpecializedContext
5034 = Specialized->getDeclContext()->getEnclosingNamespaceContext();
5035 DeclContext *DC = S.CurContext->getEnclosingNamespaceContext();
5037 getTemplateSpecializationKind(PrevDecl) == TSK_Undeclared ||
5038 getTemplateSpecializationKind(PrevDecl) == TSK_ImplicitInstantiation)){
5039 // C++ [temp.exp.spec]p2:
5040 // An explicit specialization shall be declared in the namespace of which
5041 // the template is a member, or, for member templates, in the namespace
5042 // of which the enclosing class or enclosing class template is a member.
5043 // An explicit specialization of a member function, member class or
5044 // static data member of a class template shall be declared in the
5045 // namespace of which the class template is a member.
5047 // C++0x [temp.expl.spec]p2:
5048 // An explicit specialization shall be declared in a namespace enclosing
5049 // the specialized template.
5050 if (!DC->InEnclosingNamespaceSetOf(SpecializedContext)) {
5051 bool IsCPlusPlus11Extension = DC->Encloses(SpecializedContext);
5052 if (isa<TranslationUnitDecl>(SpecializedContext)) {
5053 assert(!IsCPlusPlus11Extension &&
5054 "DC encloses TU but isn't in enclosing namespace set");
5055 S.Diag(Loc, diag::err_template_spec_decl_out_of_scope_global)
5056 << EntityKind << Specialized;
5057 } else if (isa<NamespaceDecl>(SpecializedContext)) {
5059 if (!IsCPlusPlus11Extension)
5060 Diag = diag::err_template_spec_decl_out_of_scope;
5061 else if (!S.getLangOpts().CPlusPlus11)
5062 Diag = diag::ext_template_spec_decl_out_of_scope;
5064 Diag = diag::warn_cxx98_compat_template_spec_decl_out_of_scope;
5066 << EntityKind << Specialized << cast<NamedDecl>(SpecializedContext);
5069 S.Diag(Specialized->getLocation(), diag::note_specialized_entity);
5070 ComplainedAboutScope =
5071 !(IsCPlusPlus11Extension && S.getLangOpts().CPlusPlus11);
5075 // Make sure that this redeclaration (or definition) occurs in an enclosing
5077 // Note that HandleDeclarator() performs this check for explicit
5078 // specializations of function templates, static data members, and member
5079 // functions, so we skip the check here for those kinds of entities.
5080 // FIXME: HandleDeclarator's diagnostics aren't quite as good, though.
5081 // Should we refactor that check, so that it occurs later?
5082 if (!ComplainedAboutScope && !DC->Encloses(SpecializedContext) &&
5083 !(isa<FunctionTemplateDecl>(Specialized) || isa<VarDecl>(Specialized) ||
5084 isa<FunctionDecl>(Specialized))) {
5085 if (isa<TranslationUnitDecl>(SpecializedContext))
5086 S.Diag(Loc, diag::err_template_spec_redecl_global_scope)
5087 << EntityKind << Specialized;
5088 else if (isa<NamespaceDecl>(SpecializedContext))
5089 S.Diag(Loc, diag::err_template_spec_redecl_out_of_scope)
5090 << EntityKind << Specialized
5091 << cast<NamedDecl>(SpecializedContext);
5093 S.Diag(Specialized->getLocation(), diag::note_specialized_entity);
5096 // FIXME: check for specialization-after-instantiation errors and such.
5101 /// \brief Subroutine of Sema::CheckClassTemplatePartialSpecializationArgs
5102 /// that checks non-type template partial specialization arguments.
5103 static bool CheckNonTypeClassTemplatePartialSpecializationArgs(Sema &S,
5104 NonTypeTemplateParmDecl *Param,
5105 const TemplateArgument *Args,
5107 for (unsigned I = 0; I != NumArgs; ++I) {
5108 if (Args[I].getKind() == TemplateArgument::Pack) {
5109 if (CheckNonTypeClassTemplatePartialSpecializationArgs(S, Param,
5110 Args[I].pack_begin(),
5111 Args[I].pack_size()))
5117 if (Args[I].getKind() != TemplateArgument::Expression)
5120 Expr *ArgExpr = Args[I].getAsExpr();
5122 // We can have a pack expansion of any of the bullets below.
5123 if (PackExpansionExpr *Expansion = dyn_cast<PackExpansionExpr>(ArgExpr))
5124 ArgExpr = Expansion->getPattern();
5126 // Strip off any implicit casts we added as part of type checking.
5127 while (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(ArgExpr))
5128 ArgExpr = ICE->getSubExpr();
5130 // C++ [temp.class.spec]p8:
5131 // A non-type argument is non-specialized if it is the name of a
5132 // non-type parameter. All other non-type arguments are
5135 // Below, we check the two conditions that only apply to
5136 // specialized non-type arguments, so skip any non-specialized
5138 if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(ArgExpr))
5139 if (isa<NonTypeTemplateParmDecl>(DRE->getDecl()))
5142 // C++ [temp.class.spec]p9:
5143 // Within the argument list of a class template partial
5144 // specialization, the following restrictions apply:
5145 // -- A partially specialized non-type argument expression
5146 // shall not involve a template parameter of the partial
5147 // specialization except when the argument expression is a
5148 // simple identifier.
5149 if (ArgExpr->isTypeDependent() || ArgExpr->isValueDependent()) {
5150 S.Diag(ArgExpr->getLocStart(),
5151 diag::err_dependent_non_type_arg_in_partial_spec)
5152 << ArgExpr->getSourceRange();
5156 // -- The type of a template parameter corresponding to a
5157 // specialized non-type argument shall not be dependent on a
5158 // parameter of the specialization.
5159 if (Param->getType()->isDependentType()) {
5160 S.Diag(ArgExpr->getLocStart(),
5161 diag::err_dependent_typed_non_type_arg_in_partial_spec)
5163 << ArgExpr->getSourceRange();
5164 S.Diag(Param->getLocation(), diag::note_template_param_here);
5172 /// \brief Check the non-type template arguments of a class template
5173 /// partial specialization according to C++ [temp.class.spec]p9.
5175 /// \param TemplateParams the template parameters of the primary class
5178 /// \param TemplateArgs the template arguments of the class template
5179 /// partial specialization.
5181 /// \returns true if there was an error, false otherwise.
5182 static bool CheckClassTemplatePartialSpecializationArgs(Sema &S,
5183 TemplateParameterList *TemplateParams,
5184 SmallVectorImpl<TemplateArgument> &TemplateArgs) {
5185 const TemplateArgument *ArgList = TemplateArgs.data();
5187 for (unsigned I = 0, N = TemplateParams->size(); I != N; ++I) {
5188 NonTypeTemplateParmDecl *Param
5189 = dyn_cast<NonTypeTemplateParmDecl>(TemplateParams->getParam(I));
5193 if (CheckNonTypeClassTemplatePartialSpecializationArgs(S, Param,
5202 Sema::ActOnClassTemplateSpecialization(Scope *S, unsigned TagSpec,
5204 SourceLocation KWLoc,
5205 SourceLocation ModulePrivateLoc,
5207 TemplateTy TemplateD,
5208 SourceLocation TemplateNameLoc,
5209 SourceLocation LAngleLoc,
5210 ASTTemplateArgsPtr TemplateArgsIn,
5211 SourceLocation RAngleLoc,
5212 AttributeList *Attr,
5213 MultiTemplateParamsArg TemplateParameterLists) {
5214 assert(TUK != TUK_Reference && "References are not specializations");
5216 // NOTE: KWLoc is the location of the tag keyword. This will instead
5217 // store the location of the outermost template keyword in the declaration.
5218 SourceLocation TemplateKWLoc = TemplateParameterLists.size() > 0
5219 ? TemplateParameterLists[0]->getTemplateLoc() : SourceLocation();
5221 // Find the class template we're specializing
5222 TemplateName Name = TemplateD.getAsVal<TemplateName>();
5223 ClassTemplateDecl *ClassTemplate
5224 = dyn_cast_or_null<ClassTemplateDecl>(Name.getAsTemplateDecl());
5226 if (!ClassTemplate) {
5227 Diag(TemplateNameLoc, diag::err_not_class_template_specialization)
5228 << (Name.getAsTemplateDecl() &&
5229 isa<TemplateTemplateParmDecl>(Name.getAsTemplateDecl()));
5233 bool isExplicitSpecialization = false;
5234 bool isPartialSpecialization = false;
5236 // Check the validity of the template headers that introduce this
5238 // FIXME: We probably shouldn't complain about these headers for
5239 // friend declarations.
5240 bool Invalid = false;
5241 TemplateParameterList *TemplateParams
5242 = MatchTemplateParametersToScopeSpecifier(TemplateNameLoc,
5245 TemplateParameterLists.data(),
5246 TemplateParameterLists.size(),
5248 isExplicitSpecialization,
5253 if (TemplateParams && TemplateParams->size() > 0) {
5254 isPartialSpecialization = true;
5256 if (TUK == TUK_Friend) {
5257 Diag(KWLoc, diag::err_partial_specialization_friend)
5258 << SourceRange(LAngleLoc, RAngleLoc);
5262 // C++ [temp.class.spec]p10:
5263 // The template parameter list of a specialization shall not
5264 // contain default template argument values.
5265 for (unsigned I = 0, N = TemplateParams->size(); I != N; ++I) {
5266 Decl *Param = TemplateParams->getParam(I);
5267 if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(Param)) {
5268 if (TTP->hasDefaultArgument()) {
5269 Diag(TTP->getDefaultArgumentLoc(),
5270 diag::err_default_arg_in_partial_spec);
5271 TTP->removeDefaultArgument();
5273 } else if (NonTypeTemplateParmDecl *NTTP
5274 = dyn_cast<NonTypeTemplateParmDecl>(Param)) {
5275 if (Expr *DefArg = NTTP->getDefaultArgument()) {
5276 Diag(NTTP->getDefaultArgumentLoc(),
5277 diag::err_default_arg_in_partial_spec)
5278 << DefArg->getSourceRange();
5279 NTTP->removeDefaultArgument();
5282 TemplateTemplateParmDecl *TTP = cast<TemplateTemplateParmDecl>(Param);
5283 if (TTP->hasDefaultArgument()) {
5284 Diag(TTP->getDefaultArgument().getLocation(),
5285 diag::err_default_arg_in_partial_spec)
5286 << TTP->getDefaultArgument().getSourceRange();
5287 TTP->removeDefaultArgument();
5291 } else if (TemplateParams) {
5292 if (TUK == TUK_Friend)
5293 Diag(KWLoc, diag::err_template_spec_friend)
5294 << FixItHint::CreateRemoval(
5295 SourceRange(TemplateParams->getTemplateLoc(),
5296 TemplateParams->getRAngleLoc()))
5297 << SourceRange(LAngleLoc, RAngleLoc);
5299 isExplicitSpecialization = true;
5300 } else if (TUK != TUK_Friend) {
5301 Diag(KWLoc, diag::err_template_spec_needs_header)
5302 << FixItHint::CreateInsertion(KWLoc, "template<> ");
5303 isExplicitSpecialization = true;
5306 // Check that the specialization uses the same tag kind as the
5307 // original template.
5308 TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec);
5309 assert(Kind != TTK_Enum && "Invalid enum tag in class template spec!");
5310 if (!isAcceptableTagRedeclaration(ClassTemplate->getTemplatedDecl(),
5311 Kind, TUK == TUK_Definition, KWLoc,
5312 *ClassTemplate->getIdentifier())) {
5313 Diag(KWLoc, diag::err_use_with_wrong_tag)
5315 << FixItHint::CreateReplacement(KWLoc,
5316 ClassTemplate->getTemplatedDecl()->getKindName());
5317 Diag(ClassTemplate->getTemplatedDecl()->getLocation(),
5318 diag::note_previous_use);
5319 Kind = ClassTemplate->getTemplatedDecl()->getTagKind();
5322 // Translate the parser's template argument list in our AST format.
5323 TemplateArgumentListInfo TemplateArgs;
5324 TemplateArgs.setLAngleLoc(LAngleLoc);
5325 TemplateArgs.setRAngleLoc(RAngleLoc);
5326 translateTemplateArguments(TemplateArgsIn, TemplateArgs);
5328 // Check for unexpanded parameter packs in any of the template arguments.
5329 for (unsigned I = 0, N = TemplateArgs.size(); I != N; ++I)
5330 if (DiagnoseUnexpandedParameterPack(TemplateArgs[I],
5331 UPPC_PartialSpecialization))
5334 // Check that the template argument list is well-formed for this
5336 SmallVector<TemplateArgument, 4> Converted;
5337 if (CheckTemplateArgumentList(ClassTemplate, TemplateNameLoc,
5338 TemplateArgs, false, Converted))
5341 // Find the class template (partial) specialization declaration that
5342 // corresponds to these arguments.
5343 if (isPartialSpecialization) {
5344 if (CheckClassTemplatePartialSpecializationArgs(*this,
5345 ClassTemplate->getTemplateParameters(),
5349 bool InstantiationDependent;
5350 if (!Name.isDependent() &&
5351 !TemplateSpecializationType::anyDependentTemplateArguments(
5352 TemplateArgs.getArgumentArray(),
5353 TemplateArgs.size(),
5354 InstantiationDependent)) {
5355 Diag(TemplateNameLoc, diag::err_partial_spec_fully_specialized)
5356 << ClassTemplate->getDeclName();
5357 isPartialSpecialization = false;
5361 void *InsertPos = 0;
5362 ClassTemplateSpecializationDecl *PrevDecl = 0;
5364 if (isPartialSpecialization)
5365 // FIXME: Template parameter list matters, too
5367 = ClassTemplate->findPartialSpecialization(Converted.data(),
5372 = ClassTemplate->findSpecialization(Converted.data(),
5373 Converted.size(), InsertPos);
5375 ClassTemplateSpecializationDecl *Specialization = 0;
5377 // Check whether we can declare a class template specialization in
5378 // the current scope.
5379 if (TUK != TUK_Friend &&
5380 CheckTemplateSpecializationScope(*this, ClassTemplate, PrevDecl,
5382 isPartialSpecialization))
5385 // The canonical type
5388 (PrevDecl->getSpecializationKind() == TSK_Undeclared ||
5389 TUK == TUK_Friend)) {
5390 // Since the only prior class template specialization with these
5391 // arguments was referenced but not declared, or we're only
5392 // referencing this specialization as a friend, reuse that
5393 // declaration node as our own, updating its source location and
5394 // the list of outer template parameters to reflect our new declaration.
5395 Specialization = PrevDecl;
5396 Specialization->setLocation(TemplateNameLoc);
5397 if (TemplateParameterLists.size() > 0) {
5398 Specialization->setTemplateParameterListsInfo(Context,
5399 TemplateParameterLists.size(),
5400 TemplateParameterLists.data());
5403 CanonType = Context.getTypeDeclType(Specialization);
5404 } else if (isPartialSpecialization) {
5405 // Build the canonical type that describes the converted template
5406 // arguments of the class template partial specialization.
5407 TemplateName CanonTemplate = Context.getCanonicalTemplateName(Name);
5408 CanonType = Context.getTemplateSpecializationType(CanonTemplate,
5412 if (Context.hasSameType(CanonType,
5413 ClassTemplate->getInjectedClassNameSpecialization())) {
5414 // C++ [temp.class.spec]p9b3:
5416 // -- The argument list of the specialization shall not be identical
5417 // to the implicit argument list of the primary template.
5418 Diag(TemplateNameLoc, diag::err_partial_spec_args_match_primary_template)
5419 << (TUK == TUK_Definition)
5420 << FixItHint::CreateRemoval(SourceRange(LAngleLoc, RAngleLoc));
5421 return CheckClassTemplate(S, TagSpec, TUK, KWLoc, SS,
5422 ClassTemplate->getIdentifier(),
5426 AS_none, /*ModulePrivateLoc=*/SourceLocation(),
5427 TemplateParameterLists.size() - 1,
5428 TemplateParameterLists.data());
5431 // Create a new class template partial specialization declaration node.
5432 ClassTemplatePartialSpecializationDecl *PrevPartial
5433 = cast_or_null<ClassTemplatePartialSpecializationDecl>(PrevDecl);
5434 unsigned SequenceNumber = PrevPartial? PrevPartial->getSequenceNumber()
5435 : ClassTemplate->getNextPartialSpecSequenceNumber();
5436 ClassTemplatePartialSpecializationDecl *Partial
5437 = ClassTemplatePartialSpecializationDecl::Create(Context, Kind,
5438 ClassTemplate->getDeclContext(),
5439 KWLoc, TemplateNameLoc,
5448 SetNestedNameSpecifier(Partial, SS);
5449 if (TemplateParameterLists.size() > 1 && SS.isSet()) {
5450 Partial->setTemplateParameterListsInfo(Context,
5451 TemplateParameterLists.size() - 1,
5452 TemplateParameterLists.data());
5456 ClassTemplate->AddPartialSpecialization(Partial, InsertPos);
5457 Specialization = Partial;
5459 // If we are providing an explicit specialization of a member class
5460 // template specialization, make a note of that.
5461 if (PrevPartial && PrevPartial->getInstantiatedFromMember())
5462 PrevPartial->setMemberSpecialization();
5464 // Check that all of the template parameters of the class template
5465 // partial specialization are deducible from the template
5466 // arguments. If not, this class template partial specialization
5467 // will never be used.
5468 llvm::SmallBitVector DeducibleParams(TemplateParams->size());
5469 MarkUsedTemplateParameters(Partial->getTemplateArgs(), true,
5470 TemplateParams->getDepth(),
5473 if (!DeducibleParams.all()) {
5474 unsigned NumNonDeducible = DeducibleParams.size()-DeducibleParams.count();
5475 Diag(TemplateNameLoc, diag::warn_partial_specs_not_deducible)
5476 << (NumNonDeducible > 1)
5477 << SourceRange(TemplateNameLoc, RAngleLoc);
5478 for (unsigned I = 0, N = DeducibleParams.size(); I != N; ++I) {
5479 if (!DeducibleParams[I]) {
5480 NamedDecl *Param = cast<NamedDecl>(TemplateParams->getParam(I));
5481 if (Param->getDeclName())
5482 Diag(Param->getLocation(),
5483 diag::note_partial_spec_unused_parameter)
5484 << Param->getDeclName();
5486 Diag(Param->getLocation(),
5487 diag::note_partial_spec_unused_parameter)
5493 // Create a new class template specialization declaration node for
5494 // this explicit specialization or friend declaration.
5496 = ClassTemplateSpecializationDecl::Create(Context, Kind,
5497 ClassTemplate->getDeclContext(),
5498 KWLoc, TemplateNameLoc,
5503 SetNestedNameSpecifier(Specialization, SS);
5504 if (TemplateParameterLists.size() > 0) {
5505 Specialization->setTemplateParameterListsInfo(Context,
5506 TemplateParameterLists.size(),
5507 TemplateParameterLists.data());
5511 ClassTemplate->AddSpecialization(Specialization, InsertPos);
5513 CanonType = Context.getTypeDeclType(Specialization);
5516 // C++ [temp.expl.spec]p6:
5517 // If a template, a member template or the member of a class template is
5518 // explicitly specialized then that specialization shall be declared
5519 // before the first use of that specialization that would cause an implicit
5520 // instantiation to take place, in every translation unit in which such a
5521 // use occurs; no diagnostic is required.
5522 if (PrevDecl && PrevDecl->getPointOfInstantiation().isValid()) {
5524 for (Decl *Prev = PrevDecl; Prev; Prev = Prev->getPreviousDecl()) {
5525 // Is there any previous explicit specialization declaration?
5526 if (getTemplateSpecializationKind(Prev) == TSK_ExplicitSpecialization) {
5533 SourceRange Range(TemplateNameLoc, RAngleLoc);
5534 Diag(TemplateNameLoc, diag::err_specialization_after_instantiation)
5535 << Context.getTypeDeclType(Specialization) << Range;
5537 Diag(PrevDecl->getPointOfInstantiation(),
5538 diag::note_instantiation_required_here)
5539 << (PrevDecl->getTemplateSpecializationKind()
5540 != TSK_ImplicitInstantiation);
5545 // If this is not a friend, note that this is an explicit specialization.
5546 if (TUK != TUK_Friend)
5547 Specialization->setSpecializationKind(TSK_ExplicitSpecialization);
5549 // Check that this isn't a redefinition of this specialization.
5550 if (TUK == TUK_Definition) {
5551 if (RecordDecl *Def = Specialization->getDefinition()) {
5552 SourceRange Range(TemplateNameLoc, RAngleLoc);
5553 Diag(TemplateNameLoc, diag::err_redefinition)
5554 << Context.getTypeDeclType(Specialization) << Range;
5555 Diag(Def->getLocation(), diag::note_previous_definition);
5556 Specialization->setInvalidDecl();
5562 ProcessDeclAttributeList(S, Specialization, Attr);
5564 // Add alignment attributes if necessary; these attributes are checked when
5565 // the ASTContext lays out the structure.
5566 if (TUK == TUK_Definition) {
5567 AddAlignmentAttributesForRecord(Specialization);
5568 AddMsStructLayoutForRecord(Specialization);
5571 if (ModulePrivateLoc.isValid())
5572 Diag(Specialization->getLocation(), diag::err_module_private_specialization)
5573 << (isPartialSpecialization? 1 : 0)
5574 << FixItHint::CreateRemoval(ModulePrivateLoc);
5576 // Build the fully-sugared type for this class template
5577 // specialization as the user wrote in the specialization
5578 // itself. This means that we'll pretty-print the type retrieved
5579 // from the specialization's declaration the way that the user
5580 // actually wrote the specialization, rather than formatting the
5581 // name based on the "canonical" representation used to store the
5582 // template arguments in the specialization.
5583 TypeSourceInfo *WrittenTy
5584 = Context.getTemplateSpecializationTypeInfo(Name, TemplateNameLoc,
5585 TemplateArgs, CanonType);
5586 if (TUK != TUK_Friend) {
5587 Specialization->setTypeAsWritten(WrittenTy);
5588 Specialization->setTemplateKeywordLoc(TemplateKWLoc);
5591 // C++ [temp.expl.spec]p9:
5592 // A template explicit specialization is in the scope of the
5593 // namespace in which the template was defined.
5595 // We actually implement this paragraph where we set the semantic
5596 // context (in the creation of the ClassTemplateSpecializationDecl),
5597 // but we also maintain the lexical context where the actual
5598 // definition occurs.
5599 Specialization->setLexicalDeclContext(CurContext);
5601 // We may be starting the definition of this specialization.
5602 if (TUK == TUK_Definition)
5603 Specialization->startDefinition();
5605 if (TUK == TUK_Friend) {
5606 FriendDecl *Friend = FriendDecl::Create(Context, CurContext,
5610 Friend->setAccess(AS_public);
5611 CurContext->addDecl(Friend);
5613 // Add the specialization into its lexical context, so that it can
5614 // be seen when iterating through the list of declarations in that
5615 // context. However, specializations are not found by name lookup.
5616 CurContext->addDecl(Specialization);
5618 return Specialization;
5621 Decl *Sema::ActOnTemplateDeclarator(Scope *S,
5622 MultiTemplateParamsArg TemplateParameterLists,
5624 Decl *NewDecl = HandleDeclarator(S, D, TemplateParameterLists);
5625 ActOnDocumentableDecl(NewDecl);
5629 Decl *Sema::ActOnStartOfFunctionTemplateDef(Scope *FnBodyScope,
5630 MultiTemplateParamsArg TemplateParameterLists,
5632 assert(getCurFunctionDecl() == 0 && "Function parsing confused");
5633 DeclaratorChunk::FunctionTypeInfo &FTI = D.getFunctionTypeInfo();
5635 if (FTI.hasPrototype) {
5636 // FIXME: Diagnose arguments without names in C.
5639 Scope *ParentScope = FnBodyScope->getParent();
5641 D.setFunctionDefinitionKind(FDK_Definition);
5642 Decl *DP = HandleDeclarator(ParentScope, D,
5643 TemplateParameterLists);
5644 return ActOnStartOfFunctionDef(FnBodyScope, DP);
5647 /// \brief Strips various properties off an implicit instantiation
5648 /// that has just been explicitly specialized.
5649 static void StripImplicitInstantiation(NamedDecl *D) {
5652 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
5653 FD->setInlineSpecified(false);
5655 for (FunctionDecl::param_iterator I = FD->param_begin(),
5656 E = FD->param_end();
5662 /// \brief Compute the diagnostic location for an explicit instantiation
5663 // declaration or definition.
5664 static SourceLocation DiagLocForExplicitInstantiation(
5665 NamedDecl* D, SourceLocation PointOfInstantiation) {
5666 // Explicit instantiations following a specialization have no effect and
5667 // hence no PointOfInstantiation. In that case, walk decl backwards
5668 // until a valid name loc is found.
5669 SourceLocation PrevDiagLoc = PointOfInstantiation;
5670 for (Decl *Prev = D; Prev && !PrevDiagLoc.isValid();
5671 Prev = Prev->getPreviousDecl()) {
5672 PrevDiagLoc = Prev->getLocation();
5674 assert(PrevDiagLoc.isValid() &&
5675 "Explicit instantiation without point of instantiation?");
5679 /// \brief Diagnose cases where we have an explicit template specialization
5680 /// before/after an explicit template instantiation, producing diagnostics
5681 /// for those cases where they are required and determining whether the
5682 /// new specialization/instantiation will have any effect.
5684 /// \param NewLoc the location of the new explicit specialization or
5687 /// \param NewTSK the kind of the new explicit specialization or instantiation.
5689 /// \param PrevDecl the previous declaration of the entity.
5691 /// \param PrevTSK the kind of the old explicit specialization or instantiatin.
5693 /// \param PrevPointOfInstantiation if valid, indicates where the previus
5694 /// declaration was instantiated (either implicitly or explicitly).
5696 /// \param HasNoEffect will be set to true to indicate that the new
5697 /// specialization or instantiation has no effect and should be ignored.
5699 /// \returns true if there was an error that should prevent the introduction of
5700 /// the new declaration into the AST, false otherwise.
5702 Sema::CheckSpecializationInstantiationRedecl(SourceLocation NewLoc,
5703 TemplateSpecializationKind NewTSK,
5704 NamedDecl *PrevDecl,
5705 TemplateSpecializationKind PrevTSK,
5706 SourceLocation PrevPointOfInstantiation,
5707 bool &HasNoEffect) {
5708 HasNoEffect = false;
5711 case TSK_Undeclared:
5712 case TSK_ImplicitInstantiation:
5713 llvm_unreachable("Don't check implicit instantiations here");
5715 case TSK_ExplicitSpecialization:
5717 case TSK_Undeclared:
5718 case TSK_ExplicitSpecialization:
5719 // Okay, we're just specializing something that is either already
5720 // explicitly specialized or has merely been mentioned without any
5724 case TSK_ImplicitInstantiation:
5725 if (PrevPointOfInstantiation.isInvalid()) {
5726 // The declaration itself has not actually been instantiated, so it is
5727 // still okay to specialize it.
5728 StripImplicitInstantiation(PrevDecl);
5733 case TSK_ExplicitInstantiationDeclaration:
5734 case TSK_ExplicitInstantiationDefinition:
5735 assert((PrevTSK == TSK_ImplicitInstantiation ||
5736 PrevPointOfInstantiation.isValid()) &&
5737 "Explicit instantiation without point of instantiation?");
5739 // C++ [temp.expl.spec]p6:
5740 // If a template, a member template or the member of a class template
5741 // is explicitly specialized then that specialization shall be declared
5742 // before the first use of that specialization that would cause an
5743 // implicit instantiation to take place, in every translation unit in
5744 // which such a use occurs; no diagnostic is required.
5745 for (Decl *Prev = PrevDecl; Prev; Prev = Prev->getPreviousDecl()) {
5746 // Is there any previous explicit specialization declaration?
5747 if (getTemplateSpecializationKind(Prev) == TSK_ExplicitSpecialization)
5751 Diag(NewLoc, diag::err_specialization_after_instantiation)
5753 Diag(PrevPointOfInstantiation, diag::note_instantiation_required_here)
5754 << (PrevTSK != TSK_ImplicitInstantiation);
5759 case TSK_ExplicitInstantiationDeclaration:
5761 case TSK_ExplicitInstantiationDeclaration:
5762 // This explicit instantiation declaration is redundant (that's okay).
5766 case TSK_Undeclared:
5767 case TSK_ImplicitInstantiation:
5768 // We're explicitly instantiating something that may have already been
5769 // implicitly instantiated; that's fine.
5772 case TSK_ExplicitSpecialization:
5773 // C++0x [temp.explicit]p4:
5774 // For a given set of template parameters, if an explicit instantiation
5775 // of a template appears after a declaration of an explicit
5776 // specialization for that template, the explicit instantiation has no
5781 case TSK_ExplicitInstantiationDefinition:
5782 // C++0x [temp.explicit]p10:
5783 // If an entity is the subject of both an explicit instantiation
5784 // declaration and an explicit instantiation definition in the same
5785 // translation unit, the definition shall follow the declaration.
5787 diag::err_explicit_instantiation_declaration_after_definition);
5789 // Explicit instantiations following a specialization have no effect and
5790 // hence no PrevPointOfInstantiation. In that case, walk decl backwards
5791 // until a valid name loc is found.
5792 Diag(DiagLocForExplicitInstantiation(PrevDecl, PrevPointOfInstantiation),
5793 diag::note_explicit_instantiation_definition_here);
5798 case TSK_ExplicitInstantiationDefinition:
5800 case TSK_Undeclared:
5801 case TSK_ImplicitInstantiation:
5802 // We're explicitly instantiating something that may have already been
5803 // implicitly instantiated; that's fine.
5806 case TSK_ExplicitSpecialization:
5807 // C++ DR 259, C++0x [temp.explicit]p4:
5808 // For a given set of template parameters, if an explicit
5809 // instantiation of a template appears after a declaration of
5810 // an explicit specialization for that template, the explicit
5811 // instantiation has no effect.
5813 // In C++98/03 mode, we only give an extension warning here, because it
5814 // is not harmful to try to explicitly instantiate something that
5815 // has been explicitly specialized.
5816 Diag(NewLoc, getLangOpts().CPlusPlus11 ?
5817 diag::warn_cxx98_compat_explicit_instantiation_after_specialization :
5818 diag::ext_explicit_instantiation_after_specialization)
5820 Diag(PrevDecl->getLocation(),
5821 diag::note_previous_template_specialization);
5825 case TSK_ExplicitInstantiationDeclaration:
5826 // We're explicity instantiating a definition for something for which we
5827 // were previously asked to suppress instantiations. That's fine.
5829 // C++0x [temp.explicit]p4:
5830 // For a given set of template parameters, if an explicit instantiation
5831 // of a template appears after a declaration of an explicit
5832 // specialization for that template, the explicit instantiation has no
5834 for (Decl *Prev = PrevDecl; Prev; Prev = Prev->getPreviousDecl()) {
5835 // Is there any previous explicit specialization declaration?
5836 if (getTemplateSpecializationKind(Prev) == TSK_ExplicitSpecialization) {
5844 case TSK_ExplicitInstantiationDefinition:
5845 // C++0x [temp.spec]p5:
5846 // For a given template and a given set of template-arguments,
5847 // - an explicit instantiation definition shall appear at most once
5849 Diag(NewLoc, diag::err_explicit_instantiation_duplicate)
5851 Diag(DiagLocForExplicitInstantiation(PrevDecl, PrevPointOfInstantiation),
5852 diag::note_previous_explicit_instantiation);
5858 llvm_unreachable("Missing specialization/instantiation case?");
5861 /// \brief Perform semantic analysis for the given dependent function
5862 /// template specialization.
5864 /// The only possible way to get a dependent function template specialization
5865 /// is with a friend declaration, like so:
5868 /// template \<class T> void foo(T);
5869 /// template \<class T> class A {
5870 /// friend void foo<>(T);
5874 /// There really isn't any useful analysis we can do here, so we
5875 /// just store the information.
5877 Sema::CheckDependentFunctionTemplateSpecialization(FunctionDecl *FD,
5878 const TemplateArgumentListInfo &ExplicitTemplateArgs,
5879 LookupResult &Previous) {
5880 // Remove anything from Previous that isn't a function template in
5881 // the correct context.
5882 DeclContext *FDLookupContext = FD->getDeclContext()->getRedeclContext();
5883 LookupResult::Filter F = Previous.makeFilter();
5884 while (F.hasNext()) {
5885 NamedDecl *D = F.next()->getUnderlyingDecl();
5886 if (!isa<FunctionTemplateDecl>(D) ||
5887 !FDLookupContext->InEnclosingNamespaceSetOf(
5888 D->getDeclContext()->getRedeclContext()))
5893 // Should this be diagnosed here?
5894 if (Previous.empty()) return true;
5896 FD->setDependentTemplateSpecialization(Context, Previous.asUnresolvedSet(),
5897 ExplicitTemplateArgs);
5901 /// \brief Perform semantic analysis for the given function template
5904 /// This routine performs all of the semantic analysis required for an
5905 /// explicit function template specialization. On successful completion,
5906 /// the function declaration \p FD will become a function template
5909 /// \param FD the function declaration, which will be updated to become a
5910 /// function template specialization.
5912 /// \param ExplicitTemplateArgs the explicitly-provided template arguments,
5913 /// if any. Note that this may be valid info even when 0 arguments are
5914 /// explicitly provided as in, e.g., \c void sort<>(char*, char*);
5915 /// as it anyway contains info on the angle brackets locations.
5917 /// \param Previous the set of declarations that may be specialized by
5918 /// this function specialization.
5920 Sema::CheckFunctionTemplateSpecialization(FunctionDecl *FD,
5921 TemplateArgumentListInfo *ExplicitTemplateArgs,
5922 LookupResult &Previous) {
5923 // The set of function template specializations that could match this
5924 // explicit function template specialization.
5925 UnresolvedSet<8> Candidates;
5927 DeclContext *FDLookupContext = FD->getDeclContext()->getRedeclContext();
5928 for (LookupResult::iterator I = Previous.begin(), E = Previous.end();
5930 NamedDecl *Ovl = (*I)->getUnderlyingDecl();
5931 if (FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(Ovl)) {
5932 // Only consider templates found within the same semantic lookup scope as
5934 if (!FDLookupContext->InEnclosingNamespaceSetOf(
5935 Ovl->getDeclContext()->getRedeclContext()))
5938 // When matching a constexpr member function template specialization
5939 // against the primary template, we don't yet know whether the
5940 // specialization has an implicit 'const' (because we don't know whether
5941 // it will be a static member function until we know which template it
5942 // specializes), so adjust it now assuming it specializes this template.
5943 QualType FT = FD->getType();
5944 if (FD->isConstexpr()) {
5945 CXXMethodDecl *OldMD =
5946 dyn_cast<CXXMethodDecl>(FunTmpl->getTemplatedDecl());
5947 if (OldMD && OldMD->isConst()) {
5948 const FunctionProtoType *FPT = FT->castAs<FunctionProtoType>();
5949 FunctionProtoType::ExtProtoInfo EPI = FPT->getExtProtoInfo();
5950 EPI.TypeQuals |= Qualifiers::Const;
5951 FT = Context.getFunctionType(FPT->getResultType(),
5952 ArrayRef<QualType>(FPT->arg_type_begin(),
5958 // C++ [temp.expl.spec]p11:
5959 // A trailing template-argument can be left unspecified in the
5960 // template-id naming an explicit function template specialization
5961 // provided it can be deduced from the function argument type.
5962 // Perform template argument deduction to determine whether we may be
5963 // specializing this template.
5964 // FIXME: It is somewhat wasteful to build
5965 TemplateDeductionInfo Info(FD->getLocation());
5966 FunctionDecl *Specialization = 0;
5967 if (TemplateDeductionResult TDK
5968 = DeduceTemplateArguments(FunTmpl, ExplicitTemplateArgs, FT,
5969 Specialization, Info)) {
5970 // FIXME: Template argument deduction failed; record why it failed, so
5971 // that we can provide nifty diagnostics.
5976 // Record this candidate.
5977 Candidates.addDecl(Specialization, I.getAccess());
5981 // Find the most specialized function template.
5982 UnresolvedSetIterator Result
5983 = getMostSpecialized(Candidates.begin(), Candidates.end(),
5984 TPOC_Other, 0, FD->getLocation(),
5985 PDiag(diag::err_function_template_spec_no_match)
5986 << FD->getDeclName(),
5987 PDiag(diag::err_function_template_spec_ambiguous)
5988 << FD->getDeclName() << (ExplicitTemplateArgs != 0),
5989 PDiag(diag::note_function_template_spec_matched));
5990 if (Result == Candidates.end())
5993 // Ignore access information; it doesn't figure into redeclaration checking.
5994 FunctionDecl *Specialization = cast<FunctionDecl>(*Result);
5996 FunctionTemplateSpecializationInfo *SpecInfo
5997 = Specialization->getTemplateSpecializationInfo();
5998 assert(SpecInfo && "Function template specialization info missing?");
6000 // Note: do not overwrite location info if previous template
6001 // specialization kind was explicit.
6002 TemplateSpecializationKind TSK = SpecInfo->getTemplateSpecializationKind();
6003 if (TSK == TSK_Undeclared || TSK == TSK_ImplicitInstantiation) {
6004 Specialization->setLocation(FD->getLocation());
6005 // C++11 [dcl.constexpr]p1: An explicit specialization of a constexpr
6006 // function can differ from the template declaration with respect to
6007 // the constexpr specifier.
6008 Specialization->setConstexpr(FD->isConstexpr());
6011 // FIXME: Check if the prior specialization has a point of instantiation.
6012 // If so, we have run afoul of .
6014 // If this is a friend declaration, then we're not really declaring
6015 // an explicit specialization.
6016 bool isFriend = (FD->getFriendObjectKind() != Decl::FOK_None);
6018 // Check the scope of this explicit specialization.
6020 CheckTemplateSpecializationScope(*this,
6021 Specialization->getPrimaryTemplate(),
6022 Specialization, FD->getLocation(),
6026 // C++ [temp.expl.spec]p6:
6027 // If a template, a member template or the member of a class template is
6028 // explicitly specialized then that specialization shall be declared
6029 // before the first use of that specialization that would cause an implicit
6030 // instantiation to take place, in every translation unit in which such a
6031 // use occurs; no diagnostic is required.
6032 bool HasNoEffect = false;
6034 CheckSpecializationInstantiationRedecl(FD->getLocation(),
6035 TSK_ExplicitSpecialization,
6037 SpecInfo->getTemplateSpecializationKind(),
6038 SpecInfo->getPointOfInstantiation(),
6042 // Mark the prior declaration as an explicit specialization, so that later
6043 // clients know that this is an explicit specialization.
6045 SpecInfo->setTemplateSpecializationKind(TSK_ExplicitSpecialization);
6046 MarkUnusedFileScopedDecl(Specialization);
6049 // Turn the given function declaration into a function template
6050 // specialization, with the template arguments from the previous
6052 // Take copies of (semantic and syntactic) template argument lists.
6053 const TemplateArgumentList* TemplArgs = new (Context)
6054 TemplateArgumentList(Specialization->getTemplateSpecializationArgs());
6055 FD->setFunctionTemplateSpecialization(Specialization->getPrimaryTemplate(),
6056 TemplArgs, /*InsertPos=*/0,
6057 SpecInfo->getTemplateSpecializationKind(),
6058 ExplicitTemplateArgs);
6060 // The "previous declaration" for this function template specialization is
6061 // the prior function template specialization.
6063 Previous.addDecl(Specialization);
6067 /// \brief Perform semantic analysis for the given non-template member
6070 /// This routine performs all of the semantic analysis required for an
6071 /// explicit member function specialization. On successful completion,
6072 /// the function declaration \p FD will become a member function
6075 /// \param Member the member declaration, which will be updated to become a
6078 /// \param Previous the set of declarations, one of which may be specialized
6079 /// by this function specialization; the set will be modified to contain the
6080 /// redeclared member.
6082 Sema::CheckMemberSpecialization(NamedDecl *Member, LookupResult &Previous) {
6083 assert(!isa<TemplateDecl>(Member) && "Only for non-template members");
6085 // Try to find the member we are instantiating.
6086 NamedDecl *Instantiation = 0;
6087 NamedDecl *InstantiatedFrom = 0;
6088 MemberSpecializationInfo *MSInfo = 0;
6090 if (Previous.empty()) {
6091 // Nowhere to look anyway.
6092 } else if (FunctionDecl *Function = dyn_cast<FunctionDecl>(Member)) {
6093 for (LookupResult::iterator I = Previous.begin(), E = Previous.end();
6095 NamedDecl *D = (*I)->getUnderlyingDecl();
6096 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(D)) {
6097 if (Context.hasSameType(Function->getType(), Method->getType())) {
6098 Instantiation = Method;
6099 InstantiatedFrom = Method->getInstantiatedFromMemberFunction();
6100 MSInfo = Method->getMemberSpecializationInfo();
6105 } else if (isa<VarDecl>(Member)) {
6107 if (Previous.isSingleResult() &&
6108 (PrevVar = dyn_cast<VarDecl>(Previous.getFoundDecl())))
6109 if (PrevVar->isStaticDataMember()) {
6110 Instantiation = PrevVar;
6111 InstantiatedFrom = PrevVar->getInstantiatedFromStaticDataMember();
6112 MSInfo = PrevVar->getMemberSpecializationInfo();
6114 } else if (isa<RecordDecl>(Member)) {
6115 CXXRecordDecl *PrevRecord;
6116 if (Previous.isSingleResult() &&
6117 (PrevRecord = dyn_cast<CXXRecordDecl>(Previous.getFoundDecl()))) {
6118 Instantiation = PrevRecord;
6119 InstantiatedFrom = PrevRecord->getInstantiatedFromMemberClass();
6120 MSInfo = PrevRecord->getMemberSpecializationInfo();
6122 } else if (isa<EnumDecl>(Member)) {
6124 if (Previous.isSingleResult() &&
6125 (PrevEnum = dyn_cast<EnumDecl>(Previous.getFoundDecl()))) {
6126 Instantiation = PrevEnum;
6127 InstantiatedFrom = PrevEnum->getInstantiatedFromMemberEnum();
6128 MSInfo = PrevEnum->getMemberSpecializationInfo();
6132 if (!Instantiation) {
6133 // There is no previous declaration that matches. Since member
6134 // specializations are always out-of-line, the caller will complain about
6135 // this mismatch later.
6139 // If this is a friend, just bail out here before we start turning
6140 // things into explicit specializations.
6141 if (Member->getFriendObjectKind() != Decl::FOK_None) {
6142 // Preserve instantiation information.
6143 if (InstantiatedFrom && isa<CXXMethodDecl>(Member)) {
6144 cast<CXXMethodDecl>(Member)->setInstantiationOfMemberFunction(
6145 cast<CXXMethodDecl>(InstantiatedFrom),
6146 cast<CXXMethodDecl>(Instantiation)->getTemplateSpecializationKind());
6147 } else if (InstantiatedFrom && isa<CXXRecordDecl>(Member)) {
6148 cast<CXXRecordDecl>(Member)->setInstantiationOfMemberClass(
6149 cast<CXXRecordDecl>(InstantiatedFrom),
6150 cast<CXXRecordDecl>(Instantiation)->getTemplateSpecializationKind());
6154 Previous.addDecl(Instantiation);
6158 // Make sure that this is a specialization of a member.
6159 if (!InstantiatedFrom) {
6160 Diag(Member->getLocation(), diag::err_spec_member_not_instantiated)
6162 Diag(Instantiation->getLocation(), diag::note_specialized_decl);
6166 // C++ [temp.expl.spec]p6:
6167 // If a template, a member template or the member of a class template is
6168 // explicitly specialized then that specialization shall be declared
6169 // before the first use of that specialization that would cause an implicit
6170 // instantiation to take place, in every translation unit in which such a
6171 // use occurs; no diagnostic is required.
6172 assert(MSInfo && "Member specialization info missing?");
6174 bool HasNoEffect = false;
6175 if (CheckSpecializationInstantiationRedecl(Member->getLocation(),
6176 TSK_ExplicitSpecialization,
6178 MSInfo->getTemplateSpecializationKind(),
6179 MSInfo->getPointOfInstantiation(),
6183 // Check the scope of this explicit specialization.
6184 if (CheckTemplateSpecializationScope(*this,
6186 Instantiation, Member->getLocation(),
6190 // Note that this is an explicit instantiation of a member.
6191 // the original declaration to note that it is an explicit specialization
6192 // (if it was previously an implicit instantiation). This latter step
6193 // makes bookkeeping easier.
6194 if (isa<FunctionDecl>(Member)) {
6195 FunctionDecl *InstantiationFunction = cast<FunctionDecl>(Instantiation);
6196 if (InstantiationFunction->getTemplateSpecializationKind() ==
6197 TSK_ImplicitInstantiation) {
6198 InstantiationFunction->setTemplateSpecializationKind(
6199 TSK_ExplicitSpecialization);
6200 InstantiationFunction->setLocation(Member->getLocation());
6203 cast<FunctionDecl>(Member)->setInstantiationOfMemberFunction(
6204 cast<CXXMethodDecl>(InstantiatedFrom),
6205 TSK_ExplicitSpecialization);
6206 MarkUnusedFileScopedDecl(InstantiationFunction);
6207 } else if (isa<VarDecl>(Member)) {
6208 VarDecl *InstantiationVar = cast<VarDecl>(Instantiation);
6209 if (InstantiationVar->getTemplateSpecializationKind() ==
6210 TSK_ImplicitInstantiation) {
6211 InstantiationVar->setTemplateSpecializationKind(
6212 TSK_ExplicitSpecialization);
6213 InstantiationVar->setLocation(Member->getLocation());
6216 Context.setInstantiatedFromStaticDataMember(cast<VarDecl>(Member),
6217 cast<VarDecl>(InstantiatedFrom),
6218 TSK_ExplicitSpecialization);
6219 MarkUnusedFileScopedDecl(InstantiationVar);
6220 } else if (isa<CXXRecordDecl>(Member)) {
6221 CXXRecordDecl *InstantiationClass = cast<CXXRecordDecl>(Instantiation);
6222 if (InstantiationClass->getTemplateSpecializationKind() ==
6223 TSK_ImplicitInstantiation) {
6224 InstantiationClass->setTemplateSpecializationKind(
6225 TSK_ExplicitSpecialization);
6226 InstantiationClass->setLocation(Member->getLocation());
6229 cast<CXXRecordDecl>(Member)->setInstantiationOfMemberClass(
6230 cast<CXXRecordDecl>(InstantiatedFrom),
6231 TSK_ExplicitSpecialization);
6233 assert(isa<EnumDecl>(Member) && "Only member enums remain");
6234 EnumDecl *InstantiationEnum = cast<EnumDecl>(Instantiation);
6235 if (InstantiationEnum->getTemplateSpecializationKind() ==
6236 TSK_ImplicitInstantiation) {
6237 InstantiationEnum->setTemplateSpecializationKind(
6238 TSK_ExplicitSpecialization);
6239 InstantiationEnum->setLocation(Member->getLocation());
6242 cast<EnumDecl>(Member)->setInstantiationOfMemberEnum(
6243 cast<EnumDecl>(InstantiatedFrom), TSK_ExplicitSpecialization);
6246 // Save the caller the trouble of having to figure out which declaration
6247 // this specialization matches.
6249 Previous.addDecl(Instantiation);
6253 /// \brief Check the scope of an explicit instantiation.
6255 /// \returns true if a serious error occurs, false otherwise.
6256 static bool CheckExplicitInstantiationScope(Sema &S, NamedDecl *D,
6257 SourceLocation InstLoc,
6258 bool WasQualifiedName) {
6259 DeclContext *OrigContext= D->getDeclContext()->getEnclosingNamespaceContext();
6260 DeclContext *CurContext = S.CurContext->getRedeclContext();
6262 if (CurContext->isRecord()) {
6263 S.Diag(InstLoc, diag::err_explicit_instantiation_in_class)
6268 // C++11 [temp.explicit]p3:
6269 // An explicit instantiation shall appear in an enclosing namespace of its
6270 // template. If the name declared in the explicit instantiation is an
6271 // unqualified name, the explicit instantiation shall appear in the
6272 // namespace where its template is declared or, if that namespace is inline
6273 // (7.3.1), any namespace from its enclosing namespace set.
6275 // This is DR275, which we do not retroactively apply to C++98/03.
6276 if (WasQualifiedName) {
6277 if (CurContext->Encloses(OrigContext))
6280 if (CurContext->InEnclosingNamespaceSetOf(OrigContext))
6284 if (NamespaceDecl *NS = dyn_cast<NamespaceDecl>(OrigContext)) {
6285 if (WasQualifiedName)
6287 S.getLangOpts().CPlusPlus11?
6288 diag::err_explicit_instantiation_out_of_scope :
6289 diag::warn_explicit_instantiation_out_of_scope_0x)
6293 S.getLangOpts().CPlusPlus11?
6294 diag::err_explicit_instantiation_unqualified_wrong_namespace :
6295 diag::warn_explicit_instantiation_unqualified_wrong_namespace_0x)
6299 S.getLangOpts().CPlusPlus11?
6300 diag::err_explicit_instantiation_must_be_global :
6301 diag::warn_explicit_instantiation_must_be_global_0x)
6303 S.Diag(D->getLocation(), diag::note_explicit_instantiation_here);
6307 /// \brief Determine whether the given scope specifier has a template-id in it.
6308 static bool ScopeSpecifierHasTemplateId(const CXXScopeSpec &SS) {
6312 // C++11 [temp.explicit]p3:
6313 // If the explicit instantiation is for a member function, a member class
6314 // or a static data member of a class template specialization, the name of
6315 // the class template specialization in the qualified-id for the member
6316 // name shall be a simple-template-id.
6318 // C++98 has the same restriction, just worded differently.
6319 for (NestedNameSpecifier *NNS = (NestedNameSpecifier *)SS.getScopeRep();
6320 NNS; NNS = NNS->getPrefix())
6321 if (const Type *T = NNS->getAsType())
6322 if (isa<TemplateSpecializationType>(T))
6328 // Explicit instantiation of a class template specialization
6330 Sema::ActOnExplicitInstantiation(Scope *S,
6331 SourceLocation ExternLoc,
6332 SourceLocation TemplateLoc,
6334 SourceLocation KWLoc,
6335 const CXXScopeSpec &SS,
6336 TemplateTy TemplateD,
6337 SourceLocation TemplateNameLoc,
6338 SourceLocation LAngleLoc,
6339 ASTTemplateArgsPtr TemplateArgsIn,
6340 SourceLocation RAngleLoc,
6341 AttributeList *Attr) {
6342 // Find the class template we're specializing
6343 TemplateName Name = TemplateD.getAsVal<TemplateName>();
6344 ClassTemplateDecl *ClassTemplate
6345 = cast<ClassTemplateDecl>(Name.getAsTemplateDecl());
6347 // Check that the specialization uses the same tag kind as the
6348 // original template.
6349 TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec);
6350 assert(Kind != TTK_Enum &&
6351 "Invalid enum tag in class template explicit instantiation!");
6352 if (!isAcceptableTagRedeclaration(ClassTemplate->getTemplatedDecl(),
6353 Kind, /*isDefinition*/false, KWLoc,
6354 *ClassTemplate->getIdentifier())) {
6355 Diag(KWLoc, diag::err_use_with_wrong_tag)
6357 << FixItHint::CreateReplacement(KWLoc,
6358 ClassTemplate->getTemplatedDecl()->getKindName());
6359 Diag(ClassTemplate->getTemplatedDecl()->getLocation(),
6360 diag::note_previous_use);
6361 Kind = ClassTemplate->getTemplatedDecl()->getTagKind();
6364 // C++0x [temp.explicit]p2:
6365 // There are two forms of explicit instantiation: an explicit instantiation
6366 // definition and an explicit instantiation declaration. An explicit
6367 // instantiation declaration begins with the extern keyword. [...]
6368 TemplateSpecializationKind TSK
6369 = ExternLoc.isInvalid()? TSK_ExplicitInstantiationDefinition
6370 : TSK_ExplicitInstantiationDeclaration;
6372 // Translate the parser's template argument list in our AST format.
6373 TemplateArgumentListInfo TemplateArgs(LAngleLoc, RAngleLoc);
6374 translateTemplateArguments(TemplateArgsIn, TemplateArgs);
6376 // Check that the template argument list is well-formed for this
6378 SmallVector<TemplateArgument, 4> Converted;
6379 if (CheckTemplateArgumentList(ClassTemplate, TemplateNameLoc,
6380 TemplateArgs, false, Converted))
6383 // Find the class template specialization declaration that
6384 // corresponds to these arguments.
6385 void *InsertPos = 0;
6386 ClassTemplateSpecializationDecl *PrevDecl
6387 = ClassTemplate->findSpecialization(Converted.data(),
6388 Converted.size(), InsertPos);
6390 TemplateSpecializationKind PrevDecl_TSK
6391 = PrevDecl ? PrevDecl->getTemplateSpecializationKind() : TSK_Undeclared;
6393 // C++0x [temp.explicit]p2:
6394 // [...] An explicit instantiation shall appear in an enclosing
6395 // namespace of its template. [...]
6397 // This is C++ DR 275.
6398 if (CheckExplicitInstantiationScope(*this, ClassTemplate, TemplateNameLoc,
6402 ClassTemplateSpecializationDecl *Specialization = 0;
6404 bool HasNoEffect = false;
6406 if (CheckSpecializationInstantiationRedecl(TemplateNameLoc, TSK,
6407 PrevDecl, PrevDecl_TSK,
6408 PrevDecl->getPointOfInstantiation(),
6412 // Even though HasNoEffect == true means that this explicit instantiation
6413 // has no effect on semantics, we go on to put its syntax in the AST.
6415 if (PrevDecl_TSK == TSK_ImplicitInstantiation ||
6416 PrevDecl_TSK == TSK_Undeclared) {
6417 // Since the only prior class template specialization with these
6418 // arguments was referenced but not declared, reuse that
6419 // declaration node as our own, updating the source location
6420 // for the template name to reflect our new declaration.
6421 // (Other source locations will be updated later.)
6422 Specialization = PrevDecl;
6423 Specialization->setLocation(TemplateNameLoc);
6428 if (!Specialization) {
6429 // Create a new class template specialization declaration node for
6430 // this explicit specialization.
6432 = ClassTemplateSpecializationDecl::Create(Context, Kind,
6433 ClassTemplate->getDeclContext(),
6434 KWLoc, TemplateNameLoc,
6439 SetNestedNameSpecifier(Specialization, SS);
6441 if (!HasNoEffect && !PrevDecl) {
6442 // Insert the new specialization.
6443 ClassTemplate->AddSpecialization(Specialization, InsertPos);
6447 // Build the fully-sugared type for this explicit instantiation as
6448 // the user wrote in the explicit instantiation itself. This means
6449 // that we'll pretty-print the type retrieved from the
6450 // specialization's declaration the way that the user actually wrote
6451 // the explicit instantiation, rather than formatting the name based
6452 // on the "canonical" representation used to store the template
6453 // arguments in the specialization.
6454 TypeSourceInfo *WrittenTy
6455 = Context.getTemplateSpecializationTypeInfo(Name, TemplateNameLoc,
6457 Context.getTypeDeclType(Specialization));
6458 Specialization->setTypeAsWritten(WrittenTy);
6460 // Set source locations for keywords.
6461 Specialization->setExternLoc(ExternLoc);
6462 Specialization->setTemplateKeywordLoc(TemplateLoc);
6463 Specialization->setRBraceLoc(SourceLocation());
6466 ProcessDeclAttributeList(S, Specialization, Attr);
6468 // Add the explicit instantiation into its lexical context. However,
6469 // since explicit instantiations are never found by name lookup, we
6470 // just put it into the declaration context directly.
6471 Specialization->setLexicalDeclContext(CurContext);
6472 CurContext->addDecl(Specialization);
6474 // Syntax is now OK, so return if it has no other effect on semantics.
6476 // Set the template specialization kind.
6477 Specialization->setTemplateSpecializationKind(TSK);
6478 return Specialization;
6481 // C++ [temp.explicit]p3:
6482 // A definition of a class template or class member template
6483 // shall be in scope at the point of the explicit instantiation of
6484 // the class template or class member template.
6486 // This check comes when we actually try to perform the
6488 ClassTemplateSpecializationDecl *Def
6489 = cast_or_null<ClassTemplateSpecializationDecl>(
6490 Specialization->getDefinition());
6492 InstantiateClassTemplateSpecialization(TemplateNameLoc, Specialization, TSK);
6493 else if (TSK == TSK_ExplicitInstantiationDefinition) {
6494 MarkVTableUsed(TemplateNameLoc, Specialization, true);
6495 Specialization->setPointOfInstantiation(Def->getPointOfInstantiation());
6498 // Instantiate the members of this class template specialization.
6499 Def = cast_or_null<ClassTemplateSpecializationDecl>(
6500 Specialization->getDefinition());
6502 TemplateSpecializationKind Old_TSK = Def->getTemplateSpecializationKind();
6504 // Fix a TSK_ExplicitInstantiationDeclaration followed by a
6505 // TSK_ExplicitInstantiationDefinition
6506 if (Old_TSK == TSK_ExplicitInstantiationDeclaration &&
6507 TSK == TSK_ExplicitInstantiationDefinition)
6508 Def->setTemplateSpecializationKind(TSK);
6510 InstantiateClassTemplateSpecializationMembers(TemplateNameLoc, Def, TSK);
6513 // Set the template specialization kind.
6514 Specialization->setTemplateSpecializationKind(TSK);
6515 return Specialization;
6518 // Explicit instantiation of a member class of a class template.
6520 Sema::ActOnExplicitInstantiation(Scope *S,
6521 SourceLocation ExternLoc,
6522 SourceLocation TemplateLoc,
6524 SourceLocation KWLoc,
6526 IdentifierInfo *Name,
6527 SourceLocation NameLoc,
6528 AttributeList *Attr) {
6531 bool IsDependent = false;
6532 Decl *TagD = ActOnTag(S, TagSpec, Sema::TUK_Reference,
6533 KWLoc, SS, Name, NameLoc, Attr, AS_none,
6534 /*ModulePrivateLoc=*/SourceLocation(),
6535 MultiTemplateParamsArg(), Owned, IsDependent,
6536 SourceLocation(), false, TypeResult());
6537 assert(!IsDependent && "explicit instantiation of dependent name not yet handled");
6542 TagDecl *Tag = cast<TagDecl>(TagD);
6543 assert(!Tag->isEnum() && "shouldn't see enumerations here");
6545 if (Tag->isInvalidDecl())
6548 CXXRecordDecl *Record = cast<CXXRecordDecl>(Tag);
6549 CXXRecordDecl *Pattern = Record->getInstantiatedFromMemberClass();
6551 Diag(TemplateLoc, diag::err_explicit_instantiation_nontemplate_type)
6552 << Context.getTypeDeclType(Record);
6553 Diag(Record->getLocation(), diag::note_nontemplate_decl_here);
6557 // C++0x [temp.explicit]p2:
6558 // If the explicit instantiation is for a class or member class, the
6559 // elaborated-type-specifier in the declaration shall include a
6560 // simple-template-id.
6562 // C++98 has the same restriction, just worded differently.
6563 if (!ScopeSpecifierHasTemplateId(SS))
6564 Diag(TemplateLoc, diag::ext_explicit_instantiation_without_qualified_id)
6565 << Record << SS.getRange();
6567 // C++0x [temp.explicit]p2:
6568 // There are two forms of explicit instantiation: an explicit instantiation
6569 // definition and an explicit instantiation declaration. An explicit
6570 // instantiation declaration begins with the extern keyword. [...]
6571 TemplateSpecializationKind TSK
6572 = ExternLoc.isInvalid()? TSK_ExplicitInstantiationDefinition
6573 : TSK_ExplicitInstantiationDeclaration;
6575 // C++0x [temp.explicit]p2:
6576 // [...] An explicit instantiation shall appear in an enclosing
6577 // namespace of its template. [...]
6579 // This is C++ DR 275.
6580 CheckExplicitInstantiationScope(*this, Record, NameLoc, true);
6582 // Verify that it is okay to explicitly instantiate here.
6583 CXXRecordDecl *PrevDecl
6584 = cast_or_null<CXXRecordDecl>(Record->getPreviousDecl());
6585 if (!PrevDecl && Record->getDefinition())
6588 MemberSpecializationInfo *MSInfo = PrevDecl->getMemberSpecializationInfo();
6589 bool HasNoEffect = false;
6590 assert(MSInfo && "No member specialization information?");
6591 if (CheckSpecializationInstantiationRedecl(TemplateLoc, TSK,
6593 MSInfo->getTemplateSpecializationKind(),
6594 MSInfo->getPointOfInstantiation(),
6601 CXXRecordDecl *RecordDef
6602 = cast_or_null<CXXRecordDecl>(Record->getDefinition());
6604 // C++ [temp.explicit]p3:
6605 // A definition of a member class of a class template shall be in scope
6606 // at the point of an explicit instantiation of the member class.
6608 = cast_or_null<CXXRecordDecl>(Pattern->getDefinition());
6610 Diag(TemplateLoc, diag::err_explicit_instantiation_undefined_member)
6611 << 0 << Record->getDeclName() << Record->getDeclContext();
6612 Diag(Pattern->getLocation(), diag::note_forward_declaration)
6616 if (InstantiateClass(NameLoc, Record, Def,
6617 getTemplateInstantiationArgs(Record),
6621 RecordDef = cast_or_null<CXXRecordDecl>(Record->getDefinition());
6627 // Instantiate all of the members of the class.
6628 InstantiateClassMembers(NameLoc, RecordDef,
6629 getTemplateInstantiationArgs(Record), TSK);
6631 if (TSK == TSK_ExplicitInstantiationDefinition)
6632 MarkVTableUsed(NameLoc, RecordDef, true);
6634 // FIXME: We don't have any representation for explicit instantiations of
6635 // member classes. Such a representation is not needed for compilation, but it
6636 // should be available for clients that want to see all of the declarations in
6641 DeclResult Sema::ActOnExplicitInstantiation(Scope *S,
6642 SourceLocation ExternLoc,
6643 SourceLocation TemplateLoc,
6645 // Explicit instantiations always require a name.
6646 // TODO: check if/when DNInfo should replace Name.
6647 DeclarationNameInfo NameInfo = GetNameForDeclarator(D);
6648 DeclarationName Name = NameInfo.getName();
6650 if (!D.isInvalidType())
6651 Diag(D.getDeclSpec().getLocStart(),
6652 diag::err_explicit_instantiation_requires_name)
6653 << D.getDeclSpec().getSourceRange()
6654 << D.getSourceRange();
6659 // The scope passed in may not be a decl scope. Zip up the scope tree until
6660 // we find one that is.
6661 while ((S->getFlags() & Scope::DeclScope) == 0 ||
6662 (S->getFlags() & Scope::TemplateParamScope) != 0)
6665 // Determine the type of the declaration.
6666 TypeSourceInfo *T = GetTypeForDeclarator(D, S);
6667 QualType R = T->getType();
6672 // A storage-class-specifier shall not be specified in [...] an explicit
6673 // instantiation (14.7.2) directive.
6674 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) {
6675 Diag(D.getIdentifierLoc(), diag::err_explicit_instantiation_of_typedef)
6678 } else if (D.getDeclSpec().getStorageClassSpec()
6679 != DeclSpec::SCS_unspecified) {
6680 // Complain about then remove the storage class specifier.
6681 Diag(D.getIdentifierLoc(), diag::err_explicit_instantiation_storage_class)
6682 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc());
6684 D.getMutableDeclSpec().ClearStorageClassSpecs();
6687 // C++0x [temp.explicit]p1:
6688 // [...] An explicit instantiation of a function template shall not use the
6689 // inline or constexpr specifiers.
6690 // Presumably, this also applies to member functions of class templates as
6692 if (D.getDeclSpec().isInlineSpecified())
6693 Diag(D.getDeclSpec().getInlineSpecLoc(),
6694 getLangOpts().CPlusPlus11 ?
6695 diag::err_explicit_instantiation_inline :
6696 diag::warn_explicit_instantiation_inline_0x)
6697 << FixItHint::CreateRemoval(D.getDeclSpec().getInlineSpecLoc());
6698 if (D.getDeclSpec().isConstexprSpecified())
6699 // FIXME: Add a fix-it to remove the 'constexpr' and add a 'const' if one is
6700 // not already specified.
6701 Diag(D.getDeclSpec().getConstexprSpecLoc(),
6702 diag::err_explicit_instantiation_constexpr);
6704 // C++0x [temp.explicit]p2:
6705 // There are two forms of explicit instantiation: an explicit instantiation
6706 // definition and an explicit instantiation declaration. An explicit
6707 // instantiation declaration begins with the extern keyword. [...]
6708 TemplateSpecializationKind TSK
6709 = ExternLoc.isInvalid()? TSK_ExplicitInstantiationDefinition
6710 : TSK_ExplicitInstantiationDeclaration;
6712 LookupResult Previous(*this, NameInfo, LookupOrdinaryName);
6713 LookupParsedName(Previous, S, &D.getCXXScopeSpec());
6715 if (!R->isFunctionType()) {
6716 // C++ [temp.explicit]p1:
6717 // A [...] static data member of a class template can be explicitly
6718 // instantiated from the member definition associated with its class
6720 if (Previous.isAmbiguous())
6723 VarDecl *Prev = Previous.getAsSingle<VarDecl>();
6724 if (!Prev || !Prev->isStaticDataMember()) {
6725 // We expect to see a data data member here.
6726 Diag(D.getIdentifierLoc(), diag::err_explicit_instantiation_not_known)
6728 for (LookupResult::iterator P = Previous.begin(), PEnd = Previous.end();
6730 Diag((*P)->getLocation(), diag::note_explicit_instantiation_here);
6734 if (!Prev->getInstantiatedFromStaticDataMember()) {
6735 // FIXME: Check for explicit specialization?
6736 Diag(D.getIdentifierLoc(),
6737 diag::err_explicit_instantiation_data_member_not_instantiated)
6739 Diag(Prev->getLocation(), diag::note_explicit_instantiation_here);
6740 // FIXME: Can we provide a note showing where this was declared?
6744 // C++0x [temp.explicit]p2:
6745 // If the explicit instantiation is for a member function, a member class
6746 // or a static data member of a class template specialization, the name of
6747 // the class template specialization in the qualified-id for the member
6748 // name shall be a simple-template-id.
6750 // C++98 has the same restriction, just worded differently.
6751 if (!ScopeSpecifierHasTemplateId(D.getCXXScopeSpec()))
6752 Diag(D.getIdentifierLoc(),
6753 diag::ext_explicit_instantiation_without_qualified_id)
6754 << Prev << D.getCXXScopeSpec().getRange();
6756 // Check the scope of this explicit instantiation.
6757 CheckExplicitInstantiationScope(*this, Prev, D.getIdentifierLoc(), true);
6759 // Verify that it is okay to explicitly instantiate here.
6760 MemberSpecializationInfo *MSInfo = Prev->getMemberSpecializationInfo();
6761 assert(MSInfo && "Missing static data member specialization info?");
6762 bool HasNoEffect = false;
6763 if (CheckSpecializationInstantiationRedecl(D.getIdentifierLoc(), TSK, Prev,
6764 MSInfo->getTemplateSpecializationKind(),
6765 MSInfo->getPointOfInstantiation(),
6771 // Instantiate static data member.
6772 Prev->setTemplateSpecializationKind(TSK, D.getIdentifierLoc());
6773 if (TSK == TSK_ExplicitInstantiationDefinition)
6774 InstantiateStaticDataMemberDefinition(D.getIdentifierLoc(), Prev);
6776 // FIXME: Create an ExplicitInstantiation node?
6780 // If the declarator is a template-id, translate the parser's template
6781 // argument list into our AST format.
6782 bool HasExplicitTemplateArgs = false;
6783 TemplateArgumentListInfo TemplateArgs;
6784 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) {
6785 TemplateIdAnnotation *TemplateId = D.getName().TemplateId;
6786 TemplateArgs.setLAngleLoc(TemplateId->LAngleLoc);
6787 TemplateArgs.setRAngleLoc(TemplateId->RAngleLoc);
6788 ASTTemplateArgsPtr TemplateArgsPtr(TemplateId->getTemplateArgs(),
6789 TemplateId->NumArgs);
6790 translateTemplateArguments(TemplateArgsPtr, TemplateArgs);
6791 HasExplicitTemplateArgs = true;
6794 // C++ [temp.explicit]p1:
6795 // A [...] function [...] can be explicitly instantiated from its template.
6796 // A member function [...] of a class template can be explicitly
6797 // instantiated from the member definition associated with its class
6799 UnresolvedSet<8> Matches;
6800 for (LookupResult::iterator P = Previous.begin(), PEnd = Previous.end();
6802 NamedDecl *Prev = *P;
6803 if (!HasExplicitTemplateArgs) {
6804 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Prev)) {
6805 if (Context.hasSameUnqualifiedType(Method->getType(), R)) {
6808 Matches.addDecl(Method, P.getAccess());
6809 if (Method->getTemplateSpecializationKind() == TSK_Undeclared)
6815 FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(Prev);
6819 TemplateDeductionInfo Info(D.getIdentifierLoc());
6820 FunctionDecl *Specialization = 0;
6821 if (TemplateDeductionResult TDK
6822 = DeduceTemplateArguments(FunTmpl,
6823 (HasExplicitTemplateArgs ? &TemplateArgs : 0),
6824 R, Specialization, Info)) {
6825 // FIXME: Keep track of almost-matches?
6830 Matches.addDecl(Specialization, P.getAccess());
6833 // Find the most specialized function template specialization.
6834 UnresolvedSetIterator Result
6835 = getMostSpecialized(Matches.begin(), Matches.end(), TPOC_Other, 0,
6836 D.getIdentifierLoc(),
6837 PDiag(diag::err_explicit_instantiation_not_known) << Name,
6838 PDiag(diag::err_explicit_instantiation_ambiguous) << Name,
6839 PDiag(diag::note_explicit_instantiation_candidate));
6841 if (Result == Matches.end())
6844 // Ignore access control bits, we don't need them for redeclaration checking.
6845 FunctionDecl *Specialization = cast<FunctionDecl>(*Result);
6847 if (Specialization->getTemplateSpecializationKind() == TSK_Undeclared) {
6848 Diag(D.getIdentifierLoc(),
6849 diag::err_explicit_instantiation_member_function_not_instantiated)
6851 << (Specialization->getTemplateSpecializationKind() ==
6852 TSK_ExplicitSpecialization);
6853 Diag(Specialization->getLocation(), diag::note_explicit_instantiation_here);
6857 FunctionDecl *PrevDecl = Specialization->getPreviousDecl();
6858 if (!PrevDecl && Specialization->isThisDeclarationADefinition())
6859 PrevDecl = Specialization;
6862 bool HasNoEffect = false;
6863 if (CheckSpecializationInstantiationRedecl(D.getIdentifierLoc(), TSK,
6865 PrevDecl->getTemplateSpecializationKind(),
6866 PrevDecl->getPointOfInstantiation(),
6870 // FIXME: We may still want to build some representation of this
6871 // explicit specialization.
6876 Specialization->setTemplateSpecializationKind(TSK, D.getIdentifierLoc());
6877 AttributeList *Attr = D.getDeclSpec().getAttributes().getList();
6879 ProcessDeclAttributeList(S, Specialization, Attr);
6881 if (TSK == TSK_ExplicitInstantiationDefinition)
6882 InstantiateFunctionDefinition(D.getIdentifierLoc(), Specialization);
6884 // C++0x [temp.explicit]p2:
6885 // If the explicit instantiation is for a member function, a member class
6886 // or a static data member of a class template specialization, the name of
6887 // the class template specialization in the qualified-id for the member
6888 // name shall be a simple-template-id.
6890 // C++98 has the same restriction, just worded differently.
6891 FunctionTemplateDecl *FunTmpl = Specialization->getPrimaryTemplate();
6892 if (D.getName().getKind() != UnqualifiedId::IK_TemplateId && !FunTmpl &&
6893 D.getCXXScopeSpec().isSet() &&
6894 !ScopeSpecifierHasTemplateId(D.getCXXScopeSpec()))
6895 Diag(D.getIdentifierLoc(),
6896 diag::ext_explicit_instantiation_without_qualified_id)
6897 << Specialization << D.getCXXScopeSpec().getRange();
6899 CheckExplicitInstantiationScope(*this,
6900 FunTmpl? (NamedDecl *)FunTmpl
6901 : Specialization->getInstantiatedFromMemberFunction(),
6902 D.getIdentifierLoc(),
6903 D.getCXXScopeSpec().isSet());
6905 // FIXME: Create some kind of ExplicitInstantiationDecl here.
6910 Sema::ActOnDependentTag(Scope *S, unsigned TagSpec, TagUseKind TUK,
6911 const CXXScopeSpec &SS, IdentifierInfo *Name,
6912 SourceLocation TagLoc, SourceLocation NameLoc) {
6913 // This has to hold, because SS is expected to be defined.
6914 assert(Name && "Expected a name in a dependent tag");
6916 NestedNameSpecifier *NNS
6917 = static_cast<NestedNameSpecifier *>(SS.getScopeRep());
6921 TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec);
6923 if (TUK == TUK_Declaration || TUK == TUK_Definition) {
6924 Diag(NameLoc, diag::err_dependent_tag_decl)
6925 << (TUK == TUK_Definition) << Kind << SS.getRange();
6929 // Create the resulting type.
6930 ElaboratedTypeKeyword Kwd = TypeWithKeyword::getKeywordForTagTypeKind(Kind);
6931 QualType Result = Context.getDependentNameType(Kwd, NNS, Name);
6933 // Create type-source location information for this type.
6935 DependentNameTypeLoc TL = TLB.push<DependentNameTypeLoc>(Result);
6936 TL.setElaboratedKeywordLoc(TagLoc);
6937 TL.setQualifierLoc(SS.getWithLocInContext(Context));
6938 TL.setNameLoc(NameLoc);
6939 return CreateParsedType(Result, TLB.getTypeSourceInfo(Context, Result));
6943 Sema::ActOnTypenameType(Scope *S, SourceLocation TypenameLoc,
6944 const CXXScopeSpec &SS, const IdentifierInfo &II,
6945 SourceLocation IdLoc) {
6949 if (TypenameLoc.isValid() && S && !S->getTemplateParamParent())
6951 getLangOpts().CPlusPlus11 ?
6952 diag::warn_cxx98_compat_typename_outside_of_template :
6953 diag::ext_typename_outside_of_template)
6954 << FixItHint::CreateRemoval(TypenameLoc);
6956 NestedNameSpecifierLoc QualifierLoc = SS.getWithLocInContext(Context);
6957 QualType T = CheckTypenameType(TypenameLoc.isValid()? ETK_Typename : ETK_None,
6958 TypenameLoc, QualifierLoc, II, IdLoc);
6962 TypeSourceInfo *TSI = Context.CreateTypeSourceInfo(T);
6963 if (isa<DependentNameType>(T)) {
6964 DependentNameTypeLoc TL = TSI->getTypeLoc().castAs<DependentNameTypeLoc>();
6965 TL.setElaboratedKeywordLoc(TypenameLoc);
6966 TL.setQualifierLoc(QualifierLoc);
6967 TL.setNameLoc(IdLoc);
6969 ElaboratedTypeLoc TL = TSI->getTypeLoc().castAs<ElaboratedTypeLoc>();
6970 TL.setElaboratedKeywordLoc(TypenameLoc);
6971 TL.setQualifierLoc(QualifierLoc);
6972 TL.getNamedTypeLoc().castAs<TypeSpecTypeLoc>().setNameLoc(IdLoc);
6975 return CreateParsedType(T, TSI);
6979 Sema::ActOnTypenameType(Scope *S,
6980 SourceLocation TypenameLoc,
6981 const CXXScopeSpec &SS,
6982 SourceLocation TemplateKWLoc,
6983 TemplateTy TemplateIn,
6984 SourceLocation TemplateNameLoc,
6985 SourceLocation LAngleLoc,
6986 ASTTemplateArgsPtr TemplateArgsIn,
6987 SourceLocation RAngleLoc) {
6988 if (TypenameLoc.isValid() && S && !S->getTemplateParamParent())
6990 getLangOpts().CPlusPlus11 ?
6991 diag::warn_cxx98_compat_typename_outside_of_template :
6992 diag::ext_typename_outside_of_template)
6993 << FixItHint::CreateRemoval(TypenameLoc);
6995 // Translate the parser's template argument list in our AST format.
6996 TemplateArgumentListInfo TemplateArgs(LAngleLoc, RAngleLoc);
6997 translateTemplateArguments(TemplateArgsIn, TemplateArgs);
6999 TemplateName Template = TemplateIn.get();
7000 if (DependentTemplateName *DTN = Template.getAsDependentTemplateName()) {
7001 // Construct a dependent template specialization type.
7002 assert(DTN && "dependent template has non-dependent name?");
7003 assert(DTN->getQualifier()
7004 == static_cast<NestedNameSpecifier*>(SS.getScopeRep()));
7005 QualType T = Context.getDependentTemplateSpecializationType(ETK_Typename,
7006 DTN->getQualifier(),
7007 DTN->getIdentifier(),
7010 // Create source-location information for this type.
7011 TypeLocBuilder Builder;
7012 DependentTemplateSpecializationTypeLoc SpecTL
7013 = Builder.push<DependentTemplateSpecializationTypeLoc>(T);
7014 SpecTL.setElaboratedKeywordLoc(TypenameLoc);
7015 SpecTL.setQualifierLoc(SS.getWithLocInContext(Context));
7016 SpecTL.setTemplateKeywordLoc(TemplateKWLoc);
7017 SpecTL.setTemplateNameLoc(TemplateNameLoc);
7018 SpecTL.setLAngleLoc(LAngleLoc);
7019 SpecTL.setRAngleLoc(RAngleLoc);
7020 for (unsigned I = 0, N = TemplateArgs.size(); I != N; ++I)
7021 SpecTL.setArgLocInfo(I, TemplateArgs[I].getLocInfo());
7022 return CreateParsedType(T, Builder.getTypeSourceInfo(Context, T));
7025 QualType T = CheckTemplateIdType(Template, TemplateNameLoc, TemplateArgs);
7029 // Provide source-location information for the template specialization type.
7030 TypeLocBuilder Builder;
7031 TemplateSpecializationTypeLoc SpecTL
7032 = Builder.push<TemplateSpecializationTypeLoc>(T);
7033 SpecTL.setTemplateKeywordLoc(TemplateKWLoc);
7034 SpecTL.setTemplateNameLoc(TemplateNameLoc);
7035 SpecTL.setLAngleLoc(LAngleLoc);
7036 SpecTL.setRAngleLoc(RAngleLoc);
7037 for (unsigned I = 0, N = TemplateArgs.size(); I != N; ++I)
7038 SpecTL.setArgLocInfo(I, TemplateArgs[I].getLocInfo());
7040 T = Context.getElaboratedType(ETK_Typename, SS.getScopeRep(), T);
7041 ElaboratedTypeLoc TL = Builder.push<ElaboratedTypeLoc>(T);
7042 TL.setElaboratedKeywordLoc(TypenameLoc);
7043 TL.setQualifierLoc(SS.getWithLocInContext(Context));
7045 TypeSourceInfo *TSI = Builder.getTypeSourceInfo(Context, T);
7046 return CreateParsedType(T, TSI);
7050 /// Determine whether this failed name lookup should be treated as being
7051 /// disabled by a usage of std::enable_if.
7052 static bool isEnableIf(NestedNameSpecifierLoc NNS, const IdentifierInfo &II,
7053 SourceRange &CondRange) {
7054 // We must be looking for a ::type...
7055 if (!II.isStr("type"))
7058 // ... within an explicitly-written template specialization...
7059 if (!NNS || !NNS.getNestedNameSpecifier()->getAsType())
7061 TypeLoc EnableIfTy = NNS.getTypeLoc();
7062 TemplateSpecializationTypeLoc EnableIfTSTLoc =
7063 EnableIfTy.getAs<TemplateSpecializationTypeLoc>();
7064 if (!EnableIfTSTLoc || EnableIfTSTLoc.getNumArgs() == 0)
7066 const TemplateSpecializationType *EnableIfTST =
7067 cast<TemplateSpecializationType>(EnableIfTSTLoc.getTypePtr());
7069 // ... which names a complete class template declaration...
7070 const TemplateDecl *EnableIfDecl =
7071 EnableIfTST->getTemplateName().getAsTemplateDecl();
7072 if (!EnableIfDecl || EnableIfTST->isIncompleteType())
7075 // ... called "enable_if".
7076 const IdentifierInfo *EnableIfII =
7077 EnableIfDecl->getDeclName().getAsIdentifierInfo();
7078 if (!EnableIfII || !EnableIfII->isStr("enable_if"))
7081 // Assume the first template argument is the condition.
7082 CondRange = EnableIfTSTLoc.getArgLoc(0).getSourceRange();
7086 /// \brief Build the type that describes a C++ typename specifier,
7087 /// e.g., "typename T::type".
7089 Sema::CheckTypenameType(ElaboratedTypeKeyword Keyword,
7090 SourceLocation KeywordLoc,
7091 NestedNameSpecifierLoc QualifierLoc,
7092 const IdentifierInfo &II,
7093 SourceLocation IILoc) {
7095 SS.Adopt(QualifierLoc);
7097 DeclContext *Ctx = computeDeclContext(SS);
7099 // If the nested-name-specifier is dependent and couldn't be
7100 // resolved to a type, build a typename type.
7101 assert(QualifierLoc.getNestedNameSpecifier()->isDependent());
7102 return Context.getDependentNameType(Keyword,
7103 QualifierLoc.getNestedNameSpecifier(),
7107 // If the nested-name-specifier refers to the current instantiation,
7108 // the "typename" keyword itself is superfluous. In C++03, the
7109 // program is actually ill-formed. However, DR 382 (in C++0x CD1)
7110 // allows such extraneous "typename" keywords, and we retroactively
7111 // apply this DR to C++03 code with only a warning. In any case we continue.
7113 if (RequireCompleteDeclContext(SS, Ctx))
7116 DeclarationName Name(&II);
7117 LookupResult Result(*this, Name, IILoc, LookupOrdinaryName);
7118 LookupQualifiedName(Result, Ctx);
7119 unsigned DiagID = 0;
7120 Decl *Referenced = 0;
7121 switch (Result.getResultKind()) {
7122 case LookupResult::NotFound: {
7123 // If we're looking up 'type' within a template named 'enable_if', produce
7124 // a more specific diagnostic.
7125 SourceRange CondRange;
7126 if (isEnableIf(QualifierLoc, II, CondRange)) {
7127 Diag(CondRange.getBegin(), diag::err_typename_nested_not_found_enable_if)
7128 << Ctx << CondRange;
7132 DiagID = diag::err_typename_nested_not_found;
7136 case LookupResult::FoundUnresolvedValue: {
7137 // We found a using declaration that is a value. Most likely, the using
7138 // declaration itself is meant to have the 'typename' keyword.
7139 SourceRange FullRange(KeywordLoc.isValid() ? KeywordLoc : SS.getBeginLoc(),
7141 Diag(IILoc, diag::err_typename_refers_to_using_value_decl)
7142 << Name << Ctx << FullRange;
7143 if (UnresolvedUsingValueDecl *Using
7144 = dyn_cast<UnresolvedUsingValueDecl>(Result.getRepresentativeDecl())){
7145 SourceLocation Loc = Using->getQualifierLoc().getBeginLoc();
7146 Diag(Loc, diag::note_using_value_decl_missing_typename)
7147 << FixItHint::CreateInsertion(Loc, "typename ");
7150 // Fall through to create a dependent typename type, from which we can recover
7153 case LookupResult::NotFoundInCurrentInstantiation:
7154 // Okay, it's a member of an unknown instantiation.
7155 return Context.getDependentNameType(Keyword,
7156 QualifierLoc.getNestedNameSpecifier(),
7159 case LookupResult::Found:
7160 if (TypeDecl *Type = dyn_cast<TypeDecl>(Result.getFoundDecl())) {
7161 // We found a type. Build an ElaboratedType, since the
7162 // typename-specifier was just sugar.
7163 return Context.getElaboratedType(ETK_Typename,
7164 QualifierLoc.getNestedNameSpecifier(),
7165 Context.getTypeDeclType(Type));
7168 DiagID = diag::err_typename_nested_not_type;
7169 Referenced = Result.getFoundDecl();
7172 case LookupResult::FoundOverloaded:
7173 DiagID = diag::err_typename_nested_not_type;
7174 Referenced = *Result.begin();
7177 case LookupResult::Ambiguous:
7181 // If we get here, it's because name lookup did not find a
7182 // type. Emit an appropriate diagnostic and return an error.
7183 SourceRange FullRange(KeywordLoc.isValid() ? KeywordLoc : SS.getBeginLoc(),
7185 Diag(IILoc, DiagID) << FullRange << Name << Ctx;
7187 Diag(Referenced->getLocation(), diag::note_typename_refers_here)
7193 // See Sema::RebuildTypeInCurrentInstantiation
7194 class CurrentInstantiationRebuilder
7195 : public TreeTransform<CurrentInstantiationRebuilder> {
7197 DeclarationName Entity;
7200 typedef TreeTransform<CurrentInstantiationRebuilder> inherited;
7202 CurrentInstantiationRebuilder(Sema &SemaRef,
7204 DeclarationName Entity)
7205 : TreeTransform<CurrentInstantiationRebuilder>(SemaRef),
7206 Loc(Loc), Entity(Entity) { }
7208 /// \brief Determine whether the given type \p T has already been
7211 /// For the purposes of type reconstruction, a type has already been
7212 /// transformed if it is NULL or if it is not dependent.
7213 bool AlreadyTransformed(QualType T) {
7214 return T.isNull() || !T->isDependentType();
7217 /// \brief Returns the location of the entity whose type is being
7219 SourceLocation getBaseLocation() { return Loc; }
7221 /// \brief Returns the name of the entity whose type is being rebuilt.
7222 DeclarationName getBaseEntity() { return Entity; }
7224 /// \brief Sets the "base" location and entity when that
7225 /// information is known based on another transformation.
7226 void setBase(SourceLocation Loc, DeclarationName Entity) {
7228 this->Entity = Entity;
7231 ExprResult TransformLambdaExpr(LambdaExpr *E) {
7232 // Lambdas never need to be transformed.
7238 /// \brief Rebuilds a type within the context of the current instantiation.
7240 /// The type \p T is part of the type of an out-of-line member definition of
7241 /// a class template (or class template partial specialization) that was parsed
7242 /// and constructed before we entered the scope of the class template (or
7243 /// partial specialization thereof). This routine will rebuild that type now
7244 /// that we have entered the declarator's scope, which may produce different
7245 /// canonical types, e.g.,
7248 /// template<typename T>
7250 /// typedef T* pointer;
7254 /// template<typename T>
7255 /// typename X<T>::pointer X<T>::data() { ... }
7258 /// Here, the type "typename X<T>::pointer" will be created as a DependentNameType,
7259 /// since we do not know that we can look into X<T> when we parsed the type.
7260 /// This function will rebuild the type, performing the lookup of "pointer"
7261 /// in X<T> and returning an ElaboratedType whose canonical type is the same
7262 /// as the canonical type of T*, allowing the return types of the out-of-line
7263 /// definition and the declaration to match.
7264 TypeSourceInfo *Sema::RebuildTypeInCurrentInstantiation(TypeSourceInfo *T,
7266 DeclarationName Name) {
7267 if (!T || !T->getType()->isDependentType())
7270 CurrentInstantiationRebuilder Rebuilder(*this, Loc, Name);
7271 return Rebuilder.TransformType(T);
7274 ExprResult Sema::RebuildExprInCurrentInstantiation(Expr *E) {
7275 CurrentInstantiationRebuilder Rebuilder(*this, E->getExprLoc(),
7277 return Rebuilder.TransformExpr(E);
7280 bool Sema::RebuildNestedNameSpecifierInCurrentInstantiation(CXXScopeSpec &SS) {
7284 NestedNameSpecifierLoc QualifierLoc = SS.getWithLocInContext(Context);
7285 CurrentInstantiationRebuilder Rebuilder(*this, SS.getRange().getBegin(),
7287 NestedNameSpecifierLoc Rebuilt
7288 = Rebuilder.TransformNestedNameSpecifierLoc(QualifierLoc);
7296 /// \brief Rebuild the template parameters now that we know we're in a current
7298 bool Sema::RebuildTemplateParamsInCurrentInstantiation(
7299 TemplateParameterList *Params) {
7300 for (unsigned I = 0, N = Params->size(); I != N; ++I) {
7301 Decl *Param = Params->getParam(I);
7303 // There is nothing to rebuild in a type parameter.
7304 if (isa<TemplateTypeParmDecl>(Param))
7307 // Rebuild the template parameter list of a template template parameter.
7308 if (TemplateTemplateParmDecl *TTP
7309 = dyn_cast<TemplateTemplateParmDecl>(Param)) {
7310 if (RebuildTemplateParamsInCurrentInstantiation(
7311 TTP->getTemplateParameters()))
7317 // Rebuild the type of a non-type template parameter.
7318 NonTypeTemplateParmDecl *NTTP = cast<NonTypeTemplateParmDecl>(Param);
7319 TypeSourceInfo *NewTSI
7320 = RebuildTypeInCurrentInstantiation(NTTP->getTypeSourceInfo(),
7321 NTTP->getLocation(),
7322 NTTP->getDeclName());
7326 if (NewTSI != NTTP->getTypeSourceInfo()) {
7327 NTTP->setTypeSourceInfo(NewTSI);
7328 NTTP->setType(NewTSI->getType());
7335 /// \brief Produces a formatted string that describes the binding of
7336 /// template parameters to template arguments.
7338 Sema::getTemplateArgumentBindingsText(const TemplateParameterList *Params,
7339 const TemplateArgumentList &Args) {
7340 return getTemplateArgumentBindingsText(Params, Args.data(), Args.size());
7344 Sema::getTemplateArgumentBindingsText(const TemplateParameterList *Params,
7345 const TemplateArgument *Args,
7347 SmallString<128> Str;
7348 llvm::raw_svector_ostream Out(Str);
7350 if (!Params || Params->size() == 0 || NumArgs == 0)
7351 return std::string();
7353 for (unsigned I = 0, N = Params->size(); I != N; ++I) {
7362 if (const IdentifierInfo *Id = Params->getParam(I)->getIdentifier()) {
7363 Out << Id->getName();
7369 Args[I].print(getPrintingPolicy(), Out);
7376 void Sema::MarkAsLateParsedTemplate(FunctionDecl *FD, bool Flag) {
7379 FD->setLateTemplateParsed(Flag);
7382 bool Sema::IsInsideALocalClassWithinATemplateFunction() {
7383 DeclContext *DC = CurContext;
7386 if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(CurContext)) {
7387 const FunctionDecl *FD = RD->isLocalClass();
7388 return (FD && FD->getTemplatedKind() != FunctionDecl::TK_NonTemplate);
7389 } else if (DC->isTranslationUnit() || DC->isNamespace())
7392 DC = DC->getParent();