1 //===------- SemaTemplate.cpp - Semantic Analysis for C++ Templates -------===/
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //===----------------------------------------------------------------------===/
9 // This file implements semantic analysis for C++ templates.
10 //===----------------------------------------------------------------------===/
12 #include "clang/Sema/SemaInternal.h"
13 #include "clang/Sema/Lookup.h"
14 #include "clang/Sema/Scope.h"
15 #include "clang/Sema/Template.h"
16 #include "clang/Sema/TemplateDeduction.h"
17 #include "TreeTransform.h"
18 #include "clang/AST/ASTContext.h"
19 #include "clang/AST/Expr.h"
20 #include "clang/AST/ExprCXX.h"
21 #include "clang/AST/DeclFriend.h"
22 #include "clang/AST/DeclTemplate.h"
23 #include "clang/AST/RecursiveASTVisitor.h"
24 #include "clang/AST/TypeVisitor.h"
25 #include "clang/Sema/DeclSpec.h"
26 #include "clang/Sema/ParsedTemplate.h"
27 #include "clang/Basic/LangOptions.h"
28 #include "clang/Basic/PartialDiagnostic.h"
29 #include "llvm/ADT/StringExtras.h"
30 using namespace clang;
33 // Exported for use by Parser.
35 clang::getTemplateParamsRange(TemplateParameterList const * const *Ps,
37 if (!N) return SourceRange();
38 return SourceRange(Ps[0]->getTemplateLoc(), Ps[N-1]->getRAngleLoc());
41 /// \brief Determine whether the declaration found is acceptable as the name
42 /// of a template and, if so, return that template declaration. Otherwise,
44 static NamedDecl *isAcceptableTemplateName(ASTContext &Context,
46 NamedDecl *D = Orig->getUnderlyingDecl();
48 if (isa<TemplateDecl>(D))
51 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(D)) {
52 // C++ [temp.local]p1:
53 // Like normal (non-template) classes, class templates have an
54 // injected-class-name (Clause 9). The injected-class-name
55 // can be used with or without a template-argument-list. When
56 // it is used without a template-argument-list, it is
57 // equivalent to the injected-class-name followed by the
58 // template-parameters of the class template enclosed in
59 // <>. When it is used with a template-argument-list, it
60 // refers to the specified class template specialization,
61 // which could be the current specialization or another
63 if (Record->isInjectedClassName()) {
64 Record = cast<CXXRecordDecl>(Record->getDeclContext());
65 if (Record->getDescribedClassTemplate())
66 return Record->getDescribedClassTemplate();
68 if (ClassTemplateSpecializationDecl *Spec
69 = dyn_cast<ClassTemplateSpecializationDecl>(Record))
70 return Spec->getSpecializedTemplate();
79 static void FilterAcceptableTemplateNames(ASTContext &C, LookupResult &R) {
80 // The set of class templates we've already seen.
81 llvm::SmallPtrSet<ClassTemplateDecl *, 8> ClassTemplates;
82 LookupResult::Filter filter = R.makeFilter();
83 while (filter.hasNext()) {
84 NamedDecl *Orig = filter.next();
85 NamedDecl *Repl = isAcceptableTemplateName(C, Orig);
88 else if (Repl != Orig) {
90 // C++ [temp.local]p3:
91 // A lookup that finds an injected-class-name (10.2) can result in an
92 // ambiguity in certain cases (for example, if it is found in more than
93 // one base class). If all of the injected-class-names that are found
94 // refer to specializations of the same class template, and if the name
95 // is followed by a template-argument-list, the reference refers to the
96 // class template itself and not a specialization thereof, and is not
99 // FIXME: Will we eventually have to do the same for alias templates?
100 if (ClassTemplateDecl *ClassTmpl = dyn_cast<ClassTemplateDecl>(Repl))
101 if (!ClassTemplates.insert(ClassTmpl)) {
106 // FIXME: we promote access to public here as a workaround to
107 // the fact that LookupResult doesn't let us remember that we
108 // found this template through a particular injected class name,
109 // which means we end up doing nasty things to the invariants.
110 // Pretending that access is public is *much* safer.
111 filter.replace(Repl, AS_public);
117 TemplateNameKind Sema::isTemplateName(Scope *S,
119 bool hasTemplateKeyword,
121 ParsedType ObjectTypePtr,
122 bool EnteringContext,
123 TemplateTy &TemplateResult,
124 bool &MemberOfUnknownSpecialization) {
125 assert(getLangOptions().CPlusPlus && "No template names in C!");
127 DeclarationName TName;
128 MemberOfUnknownSpecialization = false;
130 switch (Name.getKind()) {
131 case UnqualifiedId::IK_Identifier:
132 TName = DeclarationName(Name.Identifier);
135 case UnqualifiedId::IK_OperatorFunctionId:
136 TName = Context.DeclarationNames.getCXXOperatorName(
137 Name.OperatorFunctionId.Operator);
140 case UnqualifiedId::IK_LiteralOperatorId:
141 TName = Context.DeclarationNames.getCXXLiteralOperatorName(Name.Identifier);
145 return TNK_Non_template;
148 QualType ObjectType = ObjectTypePtr.get();
150 LookupResult R(*this, TName, Name.getSourceRange().getBegin(),
152 LookupTemplateName(R, S, SS, ObjectType, EnteringContext,
153 MemberOfUnknownSpecialization);
154 if (R.empty()) return TNK_Non_template;
155 if (R.isAmbiguous()) {
156 // Suppress diagnostics; we'll redo this lookup later.
157 R.suppressDiagnostics();
159 // FIXME: we might have ambiguous templates, in which case we
160 // should at least parse them properly!
161 return TNK_Non_template;
164 TemplateName Template;
165 TemplateNameKind TemplateKind;
167 unsigned ResultCount = R.end() - R.begin();
168 if (ResultCount > 1) {
169 // We assume that we'll preserve the qualifier from a function
170 // template name in other ways.
171 Template = Context.getOverloadedTemplateName(R.begin(), R.end());
172 TemplateKind = TNK_Function_template;
174 // We'll do this lookup again later.
175 R.suppressDiagnostics();
177 TemplateDecl *TD = cast<TemplateDecl>((*R.begin())->getUnderlyingDecl());
179 if (SS.isSet() && !SS.isInvalid()) {
180 NestedNameSpecifier *Qualifier
181 = static_cast<NestedNameSpecifier *>(SS.getScopeRep());
182 Template = Context.getQualifiedTemplateName(Qualifier,
183 hasTemplateKeyword, TD);
185 Template = TemplateName(TD);
188 if (isa<FunctionTemplateDecl>(TD)) {
189 TemplateKind = TNK_Function_template;
191 // We'll do this lookup again later.
192 R.suppressDiagnostics();
194 assert(isa<ClassTemplateDecl>(TD) || isa<TemplateTemplateParmDecl>(TD));
195 TemplateKind = TNK_Type_template;
199 TemplateResult = TemplateTy::make(Template);
203 bool Sema::DiagnoseUnknownTemplateName(const IdentifierInfo &II,
204 SourceLocation IILoc,
206 const CXXScopeSpec *SS,
207 TemplateTy &SuggestedTemplate,
208 TemplateNameKind &SuggestedKind) {
209 // We can't recover unless there's a dependent scope specifier preceding the
211 // FIXME: Typo correction?
212 if (!SS || !SS->isSet() || !isDependentScopeSpecifier(*SS) ||
213 computeDeclContext(*SS))
216 // The code is missing a 'template' keyword prior to the dependent template
218 NestedNameSpecifier *Qualifier = (NestedNameSpecifier*)SS->getScopeRep();
219 Diag(IILoc, diag::err_template_kw_missing)
220 << Qualifier << II.getName()
221 << FixItHint::CreateInsertion(IILoc, "template ");
223 = TemplateTy::make(Context.getDependentTemplateName(Qualifier, &II));
224 SuggestedKind = TNK_Dependent_template_name;
228 void Sema::LookupTemplateName(LookupResult &Found,
229 Scope *S, CXXScopeSpec &SS,
231 bool EnteringContext,
232 bool &MemberOfUnknownSpecialization) {
233 // Determine where to perform name lookup
234 MemberOfUnknownSpecialization = false;
235 DeclContext *LookupCtx = 0;
236 bool isDependent = false;
237 if (!ObjectType.isNull()) {
238 // This nested-name-specifier occurs in a member access expression, e.g.,
239 // x->B::f, and we are looking into the type of the object.
240 assert(!SS.isSet() && "ObjectType and scope specifier cannot coexist");
241 LookupCtx = computeDeclContext(ObjectType);
242 isDependent = ObjectType->isDependentType();
243 assert((isDependent || !ObjectType->isIncompleteType()) &&
244 "Caller should have completed object type");
245 } else if (SS.isSet()) {
246 // This nested-name-specifier occurs after another nested-name-specifier,
247 // so long into the context associated with the prior nested-name-specifier.
248 LookupCtx = computeDeclContext(SS, EnteringContext);
249 isDependent = isDependentScopeSpecifier(SS);
251 // The declaration context must be complete.
252 if (LookupCtx && RequireCompleteDeclContext(SS, LookupCtx))
256 bool ObjectTypeSearchedInScope = false;
258 // Perform "qualified" name lookup into the declaration context we
259 // computed, which is either the type of the base of a member access
260 // expression or the declaration context associated with a prior
261 // nested-name-specifier.
262 LookupQualifiedName(Found, LookupCtx);
264 if (!ObjectType.isNull() && Found.empty()) {
265 // C++ [basic.lookup.classref]p1:
266 // In a class member access expression (5.2.5), if the . or -> token is
267 // immediately followed by an identifier followed by a <, the
268 // identifier must be looked up to determine whether the < is the
269 // beginning of a template argument list (14.2) or a less-than operator.
270 // The identifier is first looked up in the class of the object
271 // expression. If the identifier is not found, it is then looked up in
272 // the context of the entire postfix-expression and shall name a class
273 // or function template.
274 if (S) LookupName(Found, S);
275 ObjectTypeSearchedInScope = true;
277 } else if (isDependent && (!S || ObjectType.isNull())) {
278 // We cannot look into a dependent object type or nested nme
280 MemberOfUnknownSpecialization = true;
283 // Perform unqualified name lookup in the current scope.
284 LookupName(Found, S);
287 if (Found.empty() && !isDependent) {
288 // If we did not find any names, attempt to correct any typos.
289 DeclarationName Name = Found.getLookupName();
290 if (DeclarationName Corrected = CorrectTypo(Found, S, &SS, LookupCtx,
291 false, CTC_CXXCasts)) {
292 FilterAcceptableTemplateNames(Context, Found);
293 if (!Found.empty()) {
295 Diag(Found.getNameLoc(), diag::err_no_member_template_suggest)
296 << Name << LookupCtx << Found.getLookupName() << SS.getRange()
297 << FixItHint::CreateReplacement(Found.getNameLoc(),
298 Found.getLookupName().getAsString());
300 Diag(Found.getNameLoc(), diag::err_no_template_suggest)
301 << Name << Found.getLookupName()
302 << FixItHint::CreateReplacement(Found.getNameLoc(),
303 Found.getLookupName().getAsString());
304 if (TemplateDecl *Template = Found.getAsSingle<TemplateDecl>())
305 Diag(Template->getLocation(), diag::note_previous_decl)
306 << Template->getDeclName();
310 Found.setLookupName(Name);
314 FilterAcceptableTemplateNames(Context, Found);
317 MemberOfUnknownSpecialization = true;
321 if (S && !ObjectType.isNull() && !ObjectTypeSearchedInScope) {
322 // C++ [basic.lookup.classref]p1:
323 // [...] If the lookup in the class of the object expression finds a
324 // template, the name is also looked up in the context of the entire
325 // postfix-expression and [...]
327 LookupResult FoundOuter(*this, Found.getLookupName(), Found.getNameLoc(),
329 LookupName(FoundOuter, S);
330 FilterAcceptableTemplateNames(Context, FoundOuter);
332 if (FoundOuter.empty()) {
333 // - if the name is not found, the name found in the class of the
334 // object expression is used, otherwise
335 } else if (!FoundOuter.getAsSingle<ClassTemplateDecl>()) {
336 // - if the name is found in the context of the entire
337 // postfix-expression and does not name a class template, the name
338 // found in the class of the object expression is used, otherwise
339 } else if (!Found.isSuppressingDiagnostics()) {
340 // - if the name found is a class template, it must refer to the same
341 // entity as the one found in the class of the object expression,
342 // otherwise the program is ill-formed.
343 if (!Found.isSingleResult() ||
344 Found.getFoundDecl()->getCanonicalDecl()
345 != FoundOuter.getFoundDecl()->getCanonicalDecl()) {
346 Diag(Found.getNameLoc(),
347 diag::ext_nested_name_member_ref_lookup_ambiguous)
348 << Found.getLookupName()
350 Diag(Found.getRepresentativeDecl()->getLocation(),
351 diag::note_ambig_member_ref_object_type)
353 Diag(FoundOuter.getFoundDecl()->getLocation(),
354 diag::note_ambig_member_ref_scope);
356 // Recover by taking the template that we found in the object
357 // expression's type.
363 /// ActOnDependentIdExpression - Handle a dependent id-expression that
364 /// was just parsed. This is only possible with an explicit scope
365 /// specifier naming a dependent type.
367 Sema::ActOnDependentIdExpression(const CXXScopeSpec &SS,
368 const DeclarationNameInfo &NameInfo,
369 bool isAddressOfOperand,
370 const TemplateArgumentListInfo *TemplateArgs) {
371 NestedNameSpecifier *Qualifier
372 = static_cast<NestedNameSpecifier*>(SS.getScopeRep());
374 DeclContext *DC = getFunctionLevelDeclContext();
376 if (!isAddressOfOperand &&
377 isa<CXXMethodDecl>(DC) &&
378 cast<CXXMethodDecl>(DC)->isInstance()) {
379 QualType ThisType = cast<CXXMethodDecl>(DC)->getThisType(Context);
381 // Since the 'this' expression is synthesized, we don't need to
382 // perform the double-lookup check.
383 NamedDecl *FirstQualifierInScope = 0;
385 return Owned(CXXDependentScopeMemberExpr::Create(Context,
386 /*This*/ 0, ThisType,
388 /*Op*/ SourceLocation(),
389 Qualifier, SS.getRange(),
390 FirstQualifierInScope,
395 return BuildDependentDeclRefExpr(SS, NameInfo, TemplateArgs);
399 Sema::BuildDependentDeclRefExpr(const CXXScopeSpec &SS,
400 const DeclarationNameInfo &NameInfo,
401 const TemplateArgumentListInfo *TemplateArgs) {
402 return Owned(DependentScopeDeclRefExpr::Create(Context,
403 static_cast<NestedNameSpecifier*>(SS.getScopeRep()),
409 /// DiagnoseTemplateParameterShadow - Produce a diagnostic complaining
410 /// that the template parameter 'PrevDecl' is being shadowed by a new
411 /// declaration at location Loc. Returns true to indicate that this is
412 /// an error, and false otherwise.
413 bool Sema::DiagnoseTemplateParameterShadow(SourceLocation Loc, Decl *PrevDecl) {
414 assert(PrevDecl->isTemplateParameter() && "Not a template parameter");
416 // Microsoft Visual C++ permits template parameters to be shadowed.
417 if (getLangOptions().Microsoft)
420 // C++ [temp.local]p4:
421 // A template-parameter shall not be redeclared within its
422 // scope (including nested scopes).
423 Diag(Loc, diag::err_template_param_shadow)
424 << cast<NamedDecl>(PrevDecl)->getDeclName();
425 Diag(PrevDecl->getLocation(), diag::note_template_param_here);
429 /// AdjustDeclIfTemplate - If the given decl happens to be a template, reset
430 /// the parameter D to reference the templated declaration and return a pointer
431 /// to the template declaration. Otherwise, do nothing to D and return null.
432 TemplateDecl *Sema::AdjustDeclIfTemplate(Decl *&D) {
433 if (TemplateDecl *Temp = dyn_cast_or_null<TemplateDecl>(D)) {
434 D = Temp->getTemplatedDecl();
440 ParsedTemplateArgument ParsedTemplateArgument::getTemplatePackExpansion(
441 SourceLocation EllipsisLoc) const {
442 assert(Kind == Template &&
443 "Only template template arguments can be pack expansions here");
444 assert(getAsTemplate().get().containsUnexpandedParameterPack() &&
445 "Template template argument pack expansion without packs");
446 ParsedTemplateArgument Result(*this);
447 Result.EllipsisLoc = EllipsisLoc;
451 static TemplateArgumentLoc translateTemplateArgument(Sema &SemaRef,
452 const ParsedTemplateArgument &Arg) {
454 switch (Arg.getKind()) {
455 case ParsedTemplateArgument::Type: {
457 QualType T = SemaRef.GetTypeFromParser(Arg.getAsType(), &DI);
459 DI = SemaRef.Context.getTrivialTypeSourceInfo(T, Arg.getLocation());
460 return TemplateArgumentLoc(TemplateArgument(T), DI);
463 case ParsedTemplateArgument::NonType: {
464 Expr *E = static_cast<Expr *>(Arg.getAsExpr());
465 return TemplateArgumentLoc(TemplateArgument(E), E);
468 case ParsedTemplateArgument::Template: {
469 TemplateName Template = Arg.getAsTemplate().get();
470 TemplateArgument TArg;
471 if (Arg.getEllipsisLoc().isValid())
472 TArg = TemplateArgument(Template, llvm::Optional<unsigned int>());
475 return TemplateArgumentLoc(TArg,
476 Arg.getScopeSpec().getRange(),
478 Arg.getEllipsisLoc());
482 llvm_unreachable("Unhandled parsed template argument");
483 return TemplateArgumentLoc();
486 /// \brief Translates template arguments as provided by the parser
487 /// into template arguments used by semantic analysis.
488 void Sema::translateTemplateArguments(const ASTTemplateArgsPtr &TemplateArgsIn,
489 TemplateArgumentListInfo &TemplateArgs) {
490 for (unsigned I = 0, Last = TemplateArgsIn.size(); I != Last; ++I)
491 TemplateArgs.addArgument(translateTemplateArgument(*this,
495 /// ActOnTypeParameter - Called when a C++ template type parameter
496 /// (e.g., "typename T") has been parsed. Typename specifies whether
497 /// the keyword "typename" was used to declare the type parameter
498 /// (otherwise, "class" was used), and KeyLoc is the location of the
499 /// "class" or "typename" keyword. ParamName is the name of the
500 /// parameter (NULL indicates an unnamed template parameter) and
501 /// ParamName is the location of the parameter name (if any).
502 /// If the type parameter has a default argument, it will be added
503 /// later via ActOnTypeParameterDefault.
504 Decl *Sema::ActOnTypeParameter(Scope *S, bool Typename, bool Ellipsis,
505 SourceLocation EllipsisLoc,
506 SourceLocation KeyLoc,
507 IdentifierInfo *ParamName,
508 SourceLocation ParamNameLoc,
509 unsigned Depth, unsigned Position,
510 SourceLocation EqualLoc,
511 ParsedType DefaultArg) {
512 assert(S->isTemplateParamScope() &&
513 "Template type parameter not in template parameter scope!");
514 bool Invalid = false;
517 NamedDecl *PrevDecl = LookupSingleName(S, ParamName, ParamNameLoc,
520 if (PrevDecl && PrevDecl->isTemplateParameter())
521 Invalid = Invalid || DiagnoseTemplateParameterShadow(ParamNameLoc,
525 SourceLocation Loc = ParamNameLoc;
529 TemplateTypeParmDecl *Param
530 = TemplateTypeParmDecl::Create(Context, Context.getTranslationUnitDecl(),
531 Loc, Depth, Position, ParamName, Typename,
534 Param->setInvalidDecl();
537 // Add the template parameter into the current scope.
539 IdResolver.AddDecl(Param);
542 // C++0x [temp.param]p9:
543 // A default template-argument may be specified for any kind of
544 // template-parameter that is not a template parameter pack.
545 if (DefaultArg && Ellipsis) {
546 Diag(EqualLoc, diag::err_template_param_pack_default_arg);
547 DefaultArg = ParsedType();
550 // Handle the default argument, if provided.
552 TypeSourceInfo *DefaultTInfo;
553 GetTypeFromParser(DefaultArg, &DefaultTInfo);
555 assert(DefaultTInfo && "expected source information for type");
557 // Check for unexpanded parameter packs.
558 if (DiagnoseUnexpandedParameterPack(Loc, DefaultTInfo,
559 UPPC_DefaultArgument))
562 // Check the template argument itself.
563 if (CheckTemplateArgument(Param, DefaultTInfo)) {
564 Param->setInvalidDecl();
568 Param->setDefaultArgument(DefaultTInfo, false);
574 /// \brief Check that the type of a non-type template parameter is
577 /// \returns the (possibly-promoted) parameter type if valid;
578 /// otherwise, produces a diagnostic and returns a NULL type.
580 Sema::CheckNonTypeTemplateParameterType(QualType T, SourceLocation Loc) {
581 // We don't allow variably-modified types as the type of non-type template
583 if (T->isVariablyModifiedType()) {
584 Diag(Loc, diag::err_variably_modified_nontype_template_param)
589 // C++ [temp.param]p4:
591 // A non-type template-parameter shall have one of the following
592 // (optionally cv-qualified) types:
594 // -- integral or enumeration type,
595 if (T->isIntegralOrEnumerationType() ||
596 // -- pointer to object or pointer to function,
597 T->isPointerType() ||
598 // -- reference to object or reference to function,
599 T->isReferenceType() ||
600 // -- pointer to member.
601 T->isMemberPointerType() ||
602 // If T is a dependent type, we can't do the check now, so we
603 // assume that it is well-formed.
604 T->isDependentType())
606 // C++ [temp.param]p8:
608 // A non-type template-parameter of type "array of T" or
609 // "function returning T" is adjusted to be of type "pointer to
610 // T" or "pointer to function returning T", respectively.
611 else if (T->isArrayType())
612 // FIXME: Keep the type prior to promotion?
613 return Context.getArrayDecayedType(T);
614 else if (T->isFunctionType())
615 // FIXME: Keep the type prior to promotion?
616 return Context.getPointerType(T);
618 Diag(Loc, diag::err_template_nontype_parm_bad_type)
624 Decl *Sema::ActOnNonTypeTemplateParameter(Scope *S, Declarator &D,
627 SourceLocation EqualLoc,
629 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S);
630 QualType T = TInfo->getType();
632 assert(S->isTemplateParamScope() &&
633 "Non-type template parameter not in template parameter scope!");
634 bool Invalid = false;
636 IdentifierInfo *ParamName = D.getIdentifier();
638 NamedDecl *PrevDecl = LookupSingleName(S, ParamName, D.getIdentifierLoc(),
641 if (PrevDecl && PrevDecl->isTemplateParameter())
642 Invalid = Invalid || DiagnoseTemplateParameterShadow(D.getIdentifierLoc(),
646 T = CheckNonTypeTemplateParameterType(T, D.getIdentifierLoc());
648 T = Context.IntTy; // Recover with an 'int' type.
652 bool IsParameterPack = D.hasEllipsis();
653 NonTypeTemplateParmDecl *Param
654 = NonTypeTemplateParmDecl::Create(Context, Context.getTranslationUnitDecl(),
655 D.getIdentifierLoc(),
656 Depth, Position, ParamName, T,
657 IsParameterPack, TInfo);
659 Param->setInvalidDecl();
661 if (D.getIdentifier()) {
662 // Add the template parameter into the current scope.
664 IdResolver.AddDecl(Param);
667 // C++0x [temp.param]p9:
668 // A default template-argument may be specified for any kind of
669 // template-parameter that is not a template parameter pack.
670 if (Default && IsParameterPack) {
671 Diag(EqualLoc, diag::err_template_param_pack_default_arg);
675 // Check the well-formedness of the default template argument, if provided.
677 // Check for unexpanded parameter packs.
678 if (DiagnoseUnexpandedParameterPack(Default, UPPC_DefaultArgument))
681 TemplateArgument Converted;
682 if (CheckTemplateArgument(Param, Param->getType(), Default, Converted)) {
683 Param->setInvalidDecl();
687 Param->setDefaultArgument(Default, false);
693 /// ActOnTemplateTemplateParameter - Called when a C++ template template
694 /// parameter (e.g. T in template <template <typename> class T> class array)
695 /// has been parsed. S is the current scope.
696 Decl *Sema::ActOnTemplateTemplateParameter(Scope* S,
697 SourceLocation TmpLoc,
698 TemplateParamsTy *Params,
699 SourceLocation EllipsisLoc,
700 IdentifierInfo *Name,
701 SourceLocation NameLoc,
704 SourceLocation EqualLoc,
705 ParsedTemplateArgument Default) {
706 assert(S->isTemplateParamScope() &&
707 "Template template parameter not in template parameter scope!");
709 // Construct the parameter object.
710 bool IsParameterPack = EllipsisLoc.isValid();
711 // FIXME: Pack-ness is dropped
712 TemplateTemplateParmDecl *Param =
713 TemplateTemplateParmDecl::Create(Context, Context.getTranslationUnitDecl(),
714 NameLoc.isInvalid()? TmpLoc : NameLoc,
715 Depth, Position, IsParameterPack,
718 // If the template template parameter has a name, then link the identifier
719 // into the scope and lookup mechanisms.
722 IdResolver.AddDecl(Param);
725 if (Params->size() == 0) {
726 Diag(Param->getLocation(), diag::err_template_template_parm_no_parms)
727 << SourceRange(Params->getLAngleLoc(), Params->getRAngleLoc());
728 Param->setInvalidDecl();
731 // C++0x [temp.param]p9:
732 // A default template-argument may be specified for any kind of
733 // template-parameter that is not a template parameter pack.
734 if (IsParameterPack && !Default.isInvalid()) {
735 Diag(EqualLoc, diag::err_template_param_pack_default_arg);
736 Default = ParsedTemplateArgument();
739 if (!Default.isInvalid()) {
740 // Check only that we have a template template argument. We don't want to
741 // try to check well-formedness now, because our template template parameter
742 // might have dependent types in its template parameters, which we wouldn't
743 // be able to match now.
745 // If none of the template template parameter's template arguments mention
746 // other template parameters, we could actually perform more checking here.
747 // However, it isn't worth doing.
748 TemplateArgumentLoc DefaultArg = translateTemplateArgument(*this, Default);
749 if (DefaultArg.getArgument().getAsTemplate().isNull()) {
750 Diag(DefaultArg.getLocation(), diag::err_template_arg_not_class_template)
751 << DefaultArg.getSourceRange();
755 // Check for unexpanded parameter packs.
756 if (DiagnoseUnexpandedParameterPack(DefaultArg.getLocation(),
757 DefaultArg.getArgument().getAsTemplate(),
758 UPPC_DefaultArgument))
761 Param->setDefaultArgument(DefaultArg, false);
767 /// ActOnTemplateParameterList - Builds a TemplateParameterList that
768 /// contains the template parameters in Params/NumParams.
769 Sema::TemplateParamsTy *
770 Sema::ActOnTemplateParameterList(unsigned Depth,
771 SourceLocation ExportLoc,
772 SourceLocation TemplateLoc,
773 SourceLocation LAngleLoc,
774 Decl **Params, unsigned NumParams,
775 SourceLocation RAngleLoc) {
776 if (ExportLoc.isValid())
777 Diag(ExportLoc, diag::warn_template_export_unsupported);
779 return TemplateParameterList::Create(Context, TemplateLoc, LAngleLoc,
780 (NamedDecl**)Params, NumParams,
784 static void SetNestedNameSpecifier(TagDecl *T, const CXXScopeSpec &SS) {
786 T->setQualifierInfo(static_cast<NestedNameSpecifier*>(SS.getScopeRep()),
791 Sema::CheckClassTemplate(Scope *S, unsigned TagSpec, TagUseKind TUK,
792 SourceLocation KWLoc, CXXScopeSpec &SS,
793 IdentifierInfo *Name, SourceLocation NameLoc,
795 TemplateParameterList *TemplateParams,
796 AccessSpecifier AS) {
797 assert(TemplateParams && TemplateParams->size() > 0 &&
798 "No template parameters");
799 assert(TUK != TUK_Reference && "Can only declare or define class templates");
800 bool Invalid = false;
802 // Check that we can declare a template here.
803 if (CheckTemplateDeclScope(S, TemplateParams))
806 TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec);
807 assert(Kind != TTK_Enum && "can't build template of enumerated type");
809 // There is no such thing as an unnamed class template.
811 Diag(KWLoc, diag::err_template_unnamed_class);
815 // Find any previous declaration with this name.
816 DeclContext *SemanticContext;
817 LookupResult Previous(*this, Name, NameLoc, LookupOrdinaryName,
819 if (SS.isNotEmpty() && !SS.isInvalid()) {
820 SemanticContext = computeDeclContext(SS, true);
821 if (!SemanticContext) {
822 // FIXME: Produce a reasonable diagnostic here
826 if (RequireCompleteDeclContext(SS, SemanticContext))
829 LookupQualifiedName(Previous, SemanticContext);
831 SemanticContext = CurContext;
832 LookupName(Previous, S);
835 if (Previous.isAmbiguous())
838 NamedDecl *PrevDecl = 0;
839 if (Previous.begin() != Previous.end())
840 PrevDecl = (*Previous.begin())->getUnderlyingDecl();
842 // If there is a previous declaration with the same name, check
843 // whether this is a valid redeclaration.
844 ClassTemplateDecl *PrevClassTemplate
845 = dyn_cast_or_null<ClassTemplateDecl>(PrevDecl);
847 // We may have found the injected-class-name of a class template,
848 // class template partial specialization, or class template specialization.
849 // In these cases, grab the template that is being defined or specialized.
850 if (!PrevClassTemplate && PrevDecl && isa<CXXRecordDecl>(PrevDecl) &&
851 cast<CXXRecordDecl>(PrevDecl)->isInjectedClassName()) {
852 PrevDecl = cast<CXXRecordDecl>(PrevDecl->getDeclContext());
854 = cast<CXXRecordDecl>(PrevDecl)->getDescribedClassTemplate();
855 if (!PrevClassTemplate && isa<ClassTemplateSpecializationDecl>(PrevDecl)) {
857 = cast<ClassTemplateSpecializationDecl>(PrevDecl)
858 ->getSpecializedTemplate();
862 if (TUK == TUK_Friend) {
863 // C++ [namespace.memdef]p3:
864 // [...] When looking for a prior declaration of a class or a function
865 // declared as a friend, and when the name of the friend class or
866 // function is neither a qualified name nor a template-id, scopes outside
867 // the innermost enclosing namespace scope are not considered.
869 DeclContext *OutermostContext = CurContext;
870 while (!OutermostContext->isFileContext())
871 OutermostContext = OutermostContext->getLookupParent();
874 (OutermostContext->Equals(PrevDecl->getDeclContext()) ||
875 OutermostContext->Encloses(PrevDecl->getDeclContext()))) {
876 SemanticContext = PrevDecl->getDeclContext();
878 // Declarations in outer scopes don't matter. However, the outermost
879 // context we computed is the semantic context for our new
881 PrevDecl = PrevClassTemplate = 0;
882 SemanticContext = OutermostContext;
886 if (CurContext->isDependentContext()) {
887 // If this is a dependent context, we don't want to link the friend
888 // class template to the template in scope, because that would perform
889 // checking of the template parameter lists that can't be performed
890 // until the outer context is instantiated.
891 PrevDecl = PrevClassTemplate = 0;
893 } else if (PrevDecl && !isDeclInScope(PrevDecl, SemanticContext, S))
894 PrevDecl = PrevClassTemplate = 0;
896 if (PrevClassTemplate) {
897 // Ensure that the template parameter lists are compatible.
898 if (!TemplateParameterListsAreEqual(TemplateParams,
899 PrevClassTemplate->getTemplateParameters(),
904 // C++ [temp.class]p4:
905 // In a redeclaration, partial specialization, explicit
906 // specialization or explicit instantiation of a class template,
907 // the class-key shall agree in kind with the original class
908 // template declaration (7.1.5.3).
909 RecordDecl *PrevRecordDecl = PrevClassTemplate->getTemplatedDecl();
910 if (!isAcceptableTagRedeclaration(PrevRecordDecl, Kind, KWLoc, *Name)) {
911 Diag(KWLoc, diag::err_use_with_wrong_tag)
913 << FixItHint::CreateReplacement(KWLoc, PrevRecordDecl->getKindName());
914 Diag(PrevRecordDecl->getLocation(), diag::note_previous_use);
915 Kind = PrevRecordDecl->getTagKind();
918 // Check for redefinition of this class template.
919 if (TUK == TUK_Definition) {
920 if (TagDecl *Def = PrevRecordDecl->getDefinition()) {
921 Diag(NameLoc, diag::err_redefinition) << Name;
922 Diag(Def->getLocation(), diag::note_previous_definition);
923 // FIXME: Would it make sense to try to "forget" the previous
924 // definition, as part of error recovery?
928 } else if (PrevDecl && PrevDecl->isTemplateParameter()) {
929 // Maybe we will complain about the shadowed template parameter.
930 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl);
931 // Just pretend that we didn't see the previous declaration.
933 } else if (PrevDecl) {
935 // A class template shall not have the same name as any other
936 // template, class, function, object, enumeration, enumerator,
937 // namespace, or type in the same scope (3.3), except as specified
939 Diag(NameLoc, diag::err_redefinition_different_kind) << Name;
940 Diag(PrevDecl->getLocation(), diag::note_previous_definition);
944 // Check the template parameter list of this declaration, possibly
945 // merging in the template parameter list from the previous class
946 // template declaration.
947 if (CheckTemplateParameterList(TemplateParams,
948 PrevClassTemplate? PrevClassTemplate->getTemplateParameters() : 0,
949 (SS.isSet() && SemanticContext &&
950 SemanticContext->isRecord() &&
951 SemanticContext->isDependentContext())
952 ? TPC_ClassTemplateMember
953 : TPC_ClassTemplate))
957 // If the name of the template was qualified, we must be defining the
958 // template out-of-line.
959 if (!SS.isInvalid() && !Invalid && !PrevClassTemplate &&
960 !(TUK == TUK_Friend && CurContext->isDependentContext()))
961 Diag(NameLoc, diag::err_member_def_does_not_match)
962 << Name << SemanticContext << SS.getRange();
965 CXXRecordDecl *NewClass =
966 CXXRecordDecl::Create(Context, Kind, SemanticContext, NameLoc, Name, KWLoc,
968 PrevClassTemplate->getTemplatedDecl() : 0,
969 /*DelayTypeCreation=*/true);
970 SetNestedNameSpecifier(NewClass, SS);
972 ClassTemplateDecl *NewTemplate
973 = ClassTemplateDecl::Create(Context, SemanticContext, NameLoc,
974 DeclarationName(Name), TemplateParams,
975 NewClass, PrevClassTemplate);
976 NewClass->setDescribedClassTemplate(NewTemplate);
978 // Build the type for the class template declaration now.
979 QualType T = NewTemplate->getInjectedClassNameSpecialization();
980 T = Context.getInjectedClassNameType(NewClass, T);
981 assert(T->isDependentType() && "Class template type is not dependent?");
984 // If we are providing an explicit specialization of a member that is a
985 // class template, make a note of that.
986 if (PrevClassTemplate &&
987 PrevClassTemplate->getInstantiatedFromMemberTemplate())
988 PrevClassTemplate->setMemberSpecialization();
990 // Set the access specifier.
991 if (!Invalid && TUK != TUK_Friend)
992 SetMemberAccessSpecifier(NewTemplate, PrevClassTemplate, AS);
994 // Set the lexical context of these templates
995 NewClass->setLexicalDeclContext(CurContext);
996 NewTemplate->setLexicalDeclContext(CurContext);
998 if (TUK == TUK_Definition)
999 NewClass->startDefinition();
1002 ProcessDeclAttributeList(S, NewClass, Attr);
1004 if (TUK != TUK_Friend)
1005 PushOnScopeChains(NewTemplate, S);
1007 if (PrevClassTemplate && PrevClassTemplate->getAccess() != AS_none) {
1008 NewTemplate->setAccess(PrevClassTemplate->getAccess());
1009 NewClass->setAccess(PrevClassTemplate->getAccess());
1012 NewTemplate->setObjectOfFriendDecl(/* PreviouslyDeclared = */
1013 PrevClassTemplate != NULL);
1015 // Friend templates are visible in fairly strange ways.
1016 if (!CurContext->isDependentContext()) {
1017 DeclContext *DC = SemanticContext->getRedeclContext();
1018 DC->makeDeclVisibleInContext(NewTemplate, /* Recoverable = */ false);
1019 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC))
1020 PushOnScopeChains(NewTemplate, EnclosingScope,
1021 /* AddToContext = */ false);
1024 FriendDecl *Friend = FriendDecl::Create(Context, CurContext,
1025 NewClass->getLocation(),
1027 /*FIXME:*/NewClass->getLocation());
1028 Friend->setAccess(AS_public);
1029 CurContext->addDecl(Friend);
1033 NewTemplate->setInvalidDecl();
1034 NewClass->setInvalidDecl();
1039 /// \brief Diagnose the presence of a default template argument on a
1040 /// template parameter, which is ill-formed in certain contexts.
1042 /// \returns true if the default template argument should be dropped.
1043 static bool DiagnoseDefaultTemplateArgument(Sema &S,
1044 Sema::TemplateParamListContext TPC,
1045 SourceLocation ParamLoc,
1046 SourceRange DefArgRange) {
1048 case Sema::TPC_ClassTemplate:
1051 case Sema::TPC_FunctionTemplate:
1052 case Sema::TPC_FriendFunctionTemplateDefinition:
1053 // C++ [temp.param]p9:
1054 // A default template-argument shall not be specified in a
1055 // function template declaration or a function template
1057 // If a friend function template declaration specifies a default
1058 // template-argument, that declaration shall be a definition and shall be
1059 // the only declaration of the function template in the translation unit.
1060 // (C++98/03 doesn't have this wording; see DR226).
1061 if (!S.getLangOptions().CPlusPlus0x)
1063 diag::ext_template_parameter_default_in_function_template)
1067 case Sema::TPC_ClassTemplateMember:
1068 // C++0x [temp.param]p9:
1069 // A default template-argument shall not be specified in the
1070 // template-parameter-lists of the definition of a member of a
1071 // class template that appears outside of the member's class.
1072 S.Diag(ParamLoc, diag::err_template_parameter_default_template_member)
1076 case Sema::TPC_FriendFunctionTemplate:
1077 // C++ [temp.param]p9:
1078 // A default template-argument shall not be specified in a
1079 // friend template declaration.
1080 S.Diag(ParamLoc, diag::err_template_parameter_default_friend_template)
1084 // FIXME: C++0x [temp.param]p9 allows default template-arguments
1085 // for friend function templates if there is only a single
1086 // declaration (and it is a definition). Strange!
1092 /// \brief Check for unexpanded parameter packs within the template parameters
1093 /// of a template template parameter, recursively.
1094 bool DiagnoseUnexpandedParameterPacks(Sema &S, TemplateTemplateParmDecl *TTP){
1095 TemplateParameterList *Params = TTP->getTemplateParameters();
1096 for (unsigned I = 0, N = Params->size(); I != N; ++I) {
1097 NamedDecl *P = Params->getParam(I);
1098 if (NonTypeTemplateParmDecl *NTTP = dyn_cast<NonTypeTemplateParmDecl>(P)) {
1099 if (S.DiagnoseUnexpandedParameterPack(NTTP->getLocation(),
1100 NTTP->getTypeSourceInfo(),
1101 Sema::UPPC_NonTypeTemplateParameterType))
1107 if (TemplateTemplateParmDecl *InnerTTP
1108 = dyn_cast<TemplateTemplateParmDecl>(P))
1109 if (DiagnoseUnexpandedParameterPacks(S, InnerTTP))
1116 /// \brief Checks the validity of a template parameter list, possibly
1117 /// considering the template parameter list from a previous
1120 /// If an "old" template parameter list is provided, it must be
1121 /// equivalent (per TemplateParameterListsAreEqual) to the "new"
1122 /// template parameter list.
1124 /// \param NewParams Template parameter list for a new template
1125 /// declaration. This template parameter list will be updated with any
1126 /// default arguments that are carried through from the previous
1127 /// template parameter list.
1129 /// \param OldParams If provided, template parameter list from a
1130 /// previous declaration of the same template. Default template
1131 /// arguments will be merged from the old template parameter list to
1132 /// the new template parameter list.
1134 /// \param TPC Describes the context in which we are checking the given
1135 /// template parameter list.
1137 /// \returns true if an error occurred, false otherwise.
1138 bool Sema::CheckTemplateParameterList(TemplateParameterList *NewParams,
1139 TemplateParameterList *OldParams,
1140 TemplateParamListContext TPC) {
1141 bool Invalid = false;
1143 // C++ [temp.param]p10:
1144 // The set of default template-arguments available for use with a
1145 // template declaration or definition is obtained by merging the
1146 // default arguments from the definition (if in scope) and all
1147 // declarations in scope in the same way default function
1148 // arguments are (8.3.6).
1149 bool SawDefaultArgument = false;
1150 SourceLocation PreviousDefaultArgLoc;
1152 bool SawParameterPack = false;
1153 SourceLocation ParameterPackLoc;
1155 // Dummy initialization to avoid warnings.
1156 TemplateParameterList::iterator OldParam = NewParams->end();
1158 OldParam = OldParams->begin();
1160 bool RemoveDefaultArguments = false;
1161 for (TemplateParameterList::iterator NewParam = NewParams->begin(),
1162 NewParamEnd = NewParams->end();
1163 NewParam != NewParamEnd; ++NewParam) {
1164 // Variables used to diagnose redundant default arguments
1165 bool RedundantDefaultArg = false;
1166 SourceLocation OldDefaultLoc;
1167 SourceLocation NewDefaultLoc;
1169 // Variables used to diagnose missing default arguments
1170 bool MissingDefaultArg = false;
1172 // C++0x [temp.param]p11:
1173 // If a template parameter of a primary class template is a template
1174 // parameter pack, it shall be the last template parameter.
1175 if (SawParameterPack && TPC == TPC_ClassTemplate) {
1176 Diag(ParameterPackLoc,
1177 diag::err_template_param_pack_must_be_last_template_parameter);
1181 if (TemplateTypeParmDecl *NewTypeParm
1182 = dyn_cast<TemplateTypeParmDecl>(*NewParam)) {
1183 // Check the presence of a default argument here.
1184 if (NewTypeParm->hasDefaultArgument() &&
1185 DiagnoseDefaultTemplateArgument(*this, TPC,
1186 NewTypeParm->getLocation(),
1187 NewTypeParm->getDefaultArgumentInfo()->getTypeLoc()
1189 NewTypeParm->removeDefaultArgument();
1191 // Merge default arguments for template type parameters.
1192 TemplateTypeParmDecl *OldTypeParm
1193 = OldParams? cast<TemplateTypeParmDecl>(*OldParam) : 0;
1195 if (NewTypeParm->isParameterPack()) {
1196 assert(!NewTypeParm->hasDefaultArgument() &&
1197 "Parameter packs can't have a default argument!");
1198 SawParameterPack = true;
1199 ParameterPackLoc = NewTypeParm->getLocation();
1200 } else if (OldTypeParm && OldTypeParm->hasDefaultArgument() &&
1201 NewTypeParm->hasDefaultArgument()) {
1202 OldDefaultLoc = OldTypeParm->getDefaultArgumentLoc();
1203 NewDefaultLoc = NewTypeParm->getDefaultArgumentLoc();
1204 SawDefaultArgument = true;
1205 RedundantDefaultArg = true;
1206 PreviousDefaultArgLoc = NewDefaultLoc;
1207 } else if (OldTypeParm && OldTypeParm->hasDefaultArgument()) {
1208 // Merge the default argument from the old declaration to the
1210 SawDefaultArgument = true;
1211 NewTypeParm->setDefaultArgument(OldTypeParm->getDefaultArgumentInfo(),
1213 PreviousDefaultArgLoc = OldTypeParm->getDefaultArgumentLoc();
1214 } else if (NewTypeParm->hasDefaultArgument()) {
1215 SawDefaultArgument = true;
1216 PreviousDefaultArgLoc = NewTypeParm->getDefaultArgumentLoc();
1217 } else if (SawDefaultArgument)
1218 MissingDefaultArg = true;
1219 } else if (NonTypeTemplateParmDecl *NewNonTypeParm
1220 = dyn_cast<NonTypeTemplateParmDecl>(*NewParam)) {
1221 // Check for unexpanded parameter packs.
1222 if (DiagnoseUnexpandedParameterPack(NewNonTypeParm->getLocation(),
1223 NewNonTypeParm->getTypeSourceInfo(),
1224 UPPC_NonTypeTemplateParameterType)) {
1229 // Check the presence of a default argument here.
1230 if (NewNonTypeParm->hasDefaultArgument() &&
1231 DiagnoseDefaultTemplateArgument(*this, TPC,
1232 NewNonTypeParm->getLocation(),
1233 NewNonTypeParm->getDefaultArgument()->getSourceRange())) {
1234 NewNonTypeParm->removeDefaultArgument();
1237 // Merge default arguments for non-type template parameters
1238 NonTypeTemplateParmDecl *OldNonTypeParm
1239 = OldParams? cast<NonTypeTemplateParmDecl>(*OldParam) : 0;
1240 if (NewNonTypeParm->isParameterPack()) {
1241 assert(!NewNonTypeParm->hasDefaultArgument() &&
1242 "Parameter packs can't have a default argument!");
1243 SawParameterPack = true;
1244 ParameterPackLoc = NewNonTypeParm->getLocation();
1245 } else if (OldNonTypeParm && OldNonTypeParm->hasDefaultArgument() &&
1246 NewNonTypeParm->hasDefaultArgument()) {
1247 OldDefaultLoc = OldNonTypeParm->getDefaultArgumentLoc();
1248 NewDefaultLoc = NewNonTypeParm->getDefaultArgumentLoc();
1249 SawDefaultArgument = true;
1250 RedundantDefaultArg = true;
1251 PreviousDefaultArgLoc = NewDefaultLoc;
1252 } else if (OldNonTypeParm && OldNonTypeParm->hasDefaultArgument()) {
1253 // Merge the default argument from the old declaration to the
1255 SawDefaultArgument = true;
1256 // FIXME: We need to create a new kind of "default argument"
1257 // expression that points to a previous non-type template
1259 NewNonTypeParm->setDefaultArgument(
1260 OldNonTypeParm->getDefaultArgument(),
1261 /*Inherited=*/ true);
1262 PreviousDefaultArgLoc = OldNonTypeParm->getDefaultArgumentLoc();
1263 } else if (NewNonTypeParm->hasDefaultArgument()) {
1264 SawDefaultArgument = true;
1265 PreviousDefaultArgLoc = NewNonTypeParm->getDefaultArgumentLoc();
1266 } else if (SawDefaultArgument)
1267 MissingDefaultArg = true;
1269 // Check the presence of a default argument here.
1270 TemplateTemplateParmDecl *NewTemplateParm
1271 = cast<TemplateTemplateParmDecl>(*NewParam);
1273 // Check for unexpanded parameter packs, recursively.
1274 if (DiagnoseUnexpandedParameterPacks(*this, NewTemplateParm)) {
1279 if (NewTemplateParm->hasDefaultArgument() &&
1280 DiagnoseDefaultTemplateArgument(*this, TPC,
1281 NewTemplateParm->getLocation(),
1282 NewTemplateParm->getDefaultArgument().getSourceRange()))
1283 NewTemplateParm->removeDefaultArgument();
1285 // Merge default arguments for template template parameters
1286 TemplateTemplateParmDecl *OldTemplateParm
1287 = OldParams? cast<TemplateTemplateParmDecl>(*OldParam) : 0;
1288 if (NewTemplateParm->isParameterPack()) {
1289 assert(!NewTemplateParm->hasDefaultArgument() &&
1290 "Parameter packs can't have a default argument!");
1291 SawParameterPack = true;
1292 ParameterPackLoc = NewTemplateParm->getLocation();
1293 } else if (OldTemplateParm && OldTemplateParm->hasDefaultArgument() &&
1294 NewTemplateParm->hasDefaultArgument()) {
1295 OldDefaultLoc = OldTemplateParm->getDefaultArgument().getLocation();
1296 NewDefaultLoc = NewTemplateParm->getDefaultArgument().getLocation();
1297 SawDefaultArgument = true;
1298 RedundantDefaultArg = true;
1299 PreviousDefaultArgLoc = NewDefaultLoc;
1300 } else if (OldTemplateParm && OldTemplateParm->hasDefaultArgument()) {
1301 // Merge the default argument from the old declaration to the
1303 SawDefaultArgument = true;
1304 // FIXME: We need to create a new kind of "default argument" expression
1305 // that points to a previous template template parameter.
1306 NewTemplateParm->setDefaultArgument(
1307 OldTemplateParm->getDefaultArgument(),
1308 /*Inherited=*/ true);
1309 PreviousDefaultArgLoc
1310 = OldTemplateParm->getDefaultArgument().getLocation();
1311 } else if (NewTemplateParm->hasDefaultArgument()) {
1312 SawDefaultArgument = true;
1313 PreviousDefaultArgLoc
1314 = NewTemplateParm->getDefaultArgument().getLocation();
1315 } else if (SawDefaultArgument)
1316 MissingDefaultArg = true;
1319 if (RedundantDefaultArg) {
1320 // C++ [temp.param]p12:
1321 // A template-parameter shall not be given default arguments
1322 // by two different declarations in the same scope.
1323 Diag(NewDefaultLoc, diag::err_template_param_default_arg_redefinition);
1324 Diag(OldDefaultLoc, diag::note_template_param_prev_default_arg);
1326 } else if (MissingDefaultArg && TPC != TPC_FunctionTemplate) {
1327 // C++ [temp.param]p11:
1328 // If a template-parameter of a class template has a default
1329 // template-argument, each subsequent template-parameter shall either
1330 // have a default template-argument supplied or be a template parameter
1332 Diag((*NewParam)->getLocation(),
1333 diag::err_template_param_default_arg_missing);
1334 Diag(PreviousDefaultArgLoc, diag::note_template_param_prev_default_arg);
1336 RemoveDefaultArguments = true;
1339 // If we have an old template parameter list that we're merging
1340 // in, move on to the next parameter.
1345 // We were missing some default arguments at the end of the list, so remove
1346 // all of the default arguments.
1347 if (RemoveDefaultArguments) {
1348 for (TemplateParameterList::iterator NewParam = NewParams->begin(),
1349 NewParamEnd = NewParams->end();
1350 NewParam != NewParamEnd; ++NewParam) {
1351 if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(*NewParam))
1352 TTP->removeDefaultArgument();
1353 else if (NonTypeTemplateParmDecl *NTTP
1354 = dyn_cast<NonTypeTemplateParmDecl>(*NewParam))
1355 NTTP->removeDefaultArgument();
1357 cast<TemplateTemplateParmDecl>(*NewParam)->removeDefaultArgument();
1366 /// A class which looks for a use of a certain level of template
1368 struct DependencyChecker : RecursiveASTVisitor<DependencyChecker> {
1369 typedef RecursiveASTVisitor<DependencyChecker> super;
1374 DependencyChecker(TemplateParameterList *Params) : Match(false) {
1375 NamedDecl *ND = Params->getParam(0);
1376 if (TemplateTypeParmDecl *PD = dyn_cast<TemplateTypeParmDecl>(ND)) {
1377 Depth = PD->getDepth();
1378 } else if (NonTypeTemplateParmDecl *PD =
1379 dyn_cast<NonTypeTemplateParmDecl>(ND)) {
1380 Depth = PD->getDepth();
1382 Depth = cast<TemplateTemplateParmDecl>(ND)->getDepth();
1386 bool Matches(unsigned ParmDepth) {
1387 if (ParmDepth >= Depth) {
1394 bool VisitTemplateTypeParmType(const TemplateTypeParmType *T) {
1395 return !Matches(T->getDepth());
1398 bool TraverseTemplateName(TemplateName N) {
1399 if (TemplateTemplateParmDecl *PD =
1400 dyn_cast_or_null<TemplateTemplateParmDecl>(N.getAsTemplateDecl()))
1401 if (Matches(PD->getDepth())) return false;
1402 return super::TraverseTemplateName(N);
1405 bool VisitDeclRefExpr(DeclRefExpr *E) {
1406 if (NonTypeTemplateParmDecl *PD =
1407 dyn_cast<NonTypeTemplateParmDecl>(E->getDecl())) {
1408 if (PD->getDepth() == Depth) {
1413 return super::VisitDeclRefExpr(E);
1418 /// Determines whether a template-id depends on the given parameter
1421 DependsOnTemplateParameters(const TemplateSpecializationType *TemplateId,
1422 TemplateParameterList *Params) {
1423 DependencyChecker Checker(Params);
1424 Checker.TraverseType(QualType(TemplateId, 0));
1425 return Checker.Match;
1428 /// \brief Match the given template parameter lists to the given scope
1429 /// specifier, returning the template parameter list that applies to the
1432 /// \param DeclStartLoc the start of the declaration that has a scope
1433 /// specifier or a template parameter list.
1435 /// \param SS the scope specifier that will be matched to the given template
1436 /// parameter lists. This scope specifier precedes a qualified name that is
1439 /// \param ParamLists the template parameter lists, from the outermost to the
1440 /// innermost template parameter lists.
1442 /// \param NumParamLists the number of template parameter lists in ParamLists.
1444 /// \param IsFriend Whether to apply the slightly different rules for
1445 /// matching template parameters to scope specifiers in friend
1448 /// \param IsExplicitSpecialization will be set true if the entity being
1449 /// declared is an explicit specialization, false otherwise.
1451 /// \returns the template parameter list, if any, that corresponds to the
1452 /// name that is preceded by the scope specifier @p SS. This template
1453 /// parameter list may be have template parameters (if we're declaring a
1454 /// template) or may have no template parameters (if we're declaring a
1455 /// template specialization), or may be NULL (if we were's declaring isn't
1456 /// itself a template).
1457 TemplateParameterList *
1458 Sema::MatchTemplateParametersToScopeSpecifier(SourceLocation DeclStartLoc,
1459 const CXXScopeSpec &SS,
1460 TemplateParameterList **ParamLists,
1461 unsigned NumParamLists,
1463 bool &IsExplicitSpecialization,
1465 IsExplicitSpecialization = false;
1467 // Find the template-ids that occur within the nested-name-specifier. These
1468 // template-ids will match up with the template parameter lists.
1469 llvm::SmallVector<const TemplateSpecializationType *, 4>
1470 TemplateIdsInSpecifier;
1471 llvm::SmallVector<ClassTemplateSpecializationDecl *, 4>
1472 ExplicitSpecializationsInSpecifier;
1473 for (NestedNameSpecifier *NNS = (NestedNameSpecifier *)SS.getScopeRep();
1474 NNS; NNS = NNS->getPrefix()) {
1475 const Type *T = NNS->getAsType();
1478 // C++0x [temp.expl.spec]p17:
1479 // A member or a member template may be nested within many
1480 // enclosing class templates. In an explicit specialization for
1481 // such a member, the member declaration shall be preceded by a
1482 // template<> for each enclosing class template that is
1483 // explicitly specialized.
1485 // Following the existing practice of GNU and EDG, we allow a typedef of a
1486 // template specialization type.
1487 while (const TypedefType *TT = dyn_cast<TypedefType>(T))
1488 T = TT->getDecl()->getUnderlyingType().getTypePtr();
1490 if (const TemplateSpecializationType *SpecType
1491 = dyn_cast<TemplateSpecializationType>(T)) {
1492 TemplateDecl *Template = SpecType->getTemplateName().getAsTemplateDecl();
1494 continue; // FIXME: should this be an error? probably...
1496 if (const RecordType *Record = SpecType->getAs<RecordType>()) {
1497 ClassTemplateSpecializationDecl *SpecDecl
1498 = cast<ClassTemplateSpecializationDecl>(Record->getDecl());
1499 // If the nested name specifier refers to an explicit specialization,
1500 // we don't need a template<> header.
1501 if (SpecDecl->getSpecializationKind() == TSK_ExplicitSpecialization) {
1502 ExplicitSpecializationsInSpecifier.push_back(SpecDecl);
1507 TemplateIdsInSpecifier.push_back(SpecType);
1511 // Reverse the list of template-ids in the scope specifier, so that we can
1512 // more easily match up the template-ids and the template parameter lists.
1513 std::reverse(TemplateIdsInSpecifier.begin(), TemplateIdsInSpecifier.end());
1515 SourceLocation FirstTemplateLoc = DeclStartLoc;
1517 FirstTemplateLoc = ParamLists[0]->getTemplateLoc();
1519 // Match the template-ids found in the specifier to the template parameter
1521 unsigned ParamIdx = 0, TemplateIdx = 0;
1522 for (unsigned NumTemplateIds = TemplateIdsInSpecifier.size();
1523 TemplateIdx != NumTemplateIds; ++TemplateIdx) {
1524 const TemplateSpecializationType *TemplateId
1525 = TemplateIdsInSpecifier[TemplateIdx];
1526 bool DependentTemplateId = TemplateId->isDependentType();
1528 // In friend declarations we can have template-ids which don't
1529 // depend on the corresponding template parameter lists. But
1530 // assume that empty parameter lists are supposed to match this
1532 if (IsFriend && ParamIdx < NumParamLists && ParamLists[ParamIdx]->size()) {
1533 if (!DependentTemplateId ||
1534 !DependsOnTemplateParameters(TemplateId, ParamLists[ParamIdx]))
1538 if (ParamIdx >= NumParamLists) {
1539 // We have a template-id without a corresponding template parameter
1542 // ...which is fine if this is a friend declaration.
1544 IsExplicitSpecialization = true;
1548 if (DependentTemplateId) {
1549 // FIXME: the location information here isn't great.
1550 Diag(SS.getRange().getBegin(),
1551 diag::err_template_spec_needs_template_parameters)
1552 << QualType(TemplateId, 0)
1556 Diag(SS.getRange().getBegin(), diag::err_template_spec_needs_header)
1558 << FixItHint::CreateInsertion(FirstTemplateLoc, "template<> ");
1559 IsExplicitSpecialization = true;
1564 // Check the template parameter list against its corresponding template-id.
1565 if (DependentTemplateId) {
1566 TemplateParameterList *ExpectedTemplateParams = 0;
1568 // Are there cases in (e.g.) friends where this won't match?
1569 if (const InjectedClassNameType *Injected
1570 = TemplateId->getAs<InjectedClassNameType>()) {
1571 CXXRecordDecl *Record = Injected->getDecl();
1572 if (ClassTemplatePartialSpecializationDecl *Partial =
1573 dyn_cast<ClassTemplatePartialSpecializationDecl>(Record))
1574 ExpectedTemplateParams = Partial->getTemplateParameters();
1576 ExpectedTemplateParams = Record->getDescribedClassTemplate()
1577 ->getTemplateParameters();
1580 if (ExpectedTemplateParams)
1581 TemplateParameterListsAreEqual(ParamLists[ParamIdx],
1582 ExpectedTemplateParams,
1583 true, TPL_TemplateMatch);
1585 CheckTemplateParameterList(ParamLists[ParamIdx], 0,
1586 TPC_ClassTemplateMember);
1587 } else if (ParamLists[ParamIdx]->size() > 0)
1588 Diag(ParamLists[ParamIdx]->getTemplateLoc(),
1589 diag::err_template_param_list_matches_nontemplate)
1591 << ParamLists[ParamIdx]->getSourceRange();
1593 IsExplicitSpecialization = true;
1598 // If there were at least as many template-ids as there were template
1599 // parameter lists, then there are no template parameter lists remaining for
1600 // the declaration itself.
1601 if (ParamIdx >= NumParamLists)
1604 // If there were too many template parameter lists, complain about that now.
1605 if (ParamIdx != NumParamLists - 1) {
1606 while (ParamIdx < NumParamLists - 1) {
1607 bool isExplicitSpecHeader = ParamLists[ParamIdx]->size() == 0;
1608 Diag(ParamLists[ParamIdx]->getTemplateLoc(),
1609 isExplicitSpecHeader? diag::warn_template_spec_extra_headers
1610 : diag::err_template_spec_extra_headers)
1611 << SourceRange(ParamLists[ParamIdx]->getTemplateLoc(),
1612 ParamLists[ParamIdx]->getRAngleLoc());
1614 if (isExplicitSpecHeader && !ExplicitSpecializationsInSpecifier.empty()) {
1615 Diag(ExplicitSpecializationsInSpecifier.back()->getLocation(),
1616 diag::note_explicit_template_spec_does_not_need_header)
1617 << ExplicitSpecializationsInSpecifier.back();
1618 ExplicitSpecializationsInSpecifier.pop_back();
1621 // We have a template parameter list with no corresponding scope, which
1622 // means that the resulting template declaration can't be instantiated
1623 // properly (we'll end up with dependent nodes when we shouldn't).
1624 if (!isExplicitSpecHeader)
1631 // Return the last template parameter list, which corresponds to the
1632 // entity being declared.
1633 return ParamLists[NumParamLists - 1];
1636 QualType Sema::CheckTemplateIdType(TemplateName Name,
1637 SourceLocation TemplateLoc,
1638 const TemplateArgumentListInfo &TemplateArgs) {
1639 TemplateDecl *Template = Name.getAsTemplateDecl();
1641 // The template name does not resolve to a template, so we just
1642 // build a dependent template-id type.
1643 return Context.getTemplateSpecializationType(Name, TemplateArgs);
1646 // Check that the template argument list is well-formed for this
1648 llvm::SmallVector<TemplateArgument, 4> Converted;
1649 if (CheckTemplateArgumentList(Template, TemplateLoc, TemplateArgs,
1653 assert((Converted.size() == Template->getTemplateParameters()->size()) &&
1654 "Converted template argument list is too short!");
1658 if (Name.isDependent() ||
1659 TemplateSpecializationType::anyDependentTemplateArguments(
1661 // This class template specialization is a dependent
1662 // type. Therefore, its canonical type is another class template
1663 // specialization type that contains all of the converted
1664 // arguments in canonical form. This ensures that, e.g., A<T> and
1665 // A<T, T> have identical types when A is declared as:
1667 // template<typename T, typename U = T> struct A;
1668 TemplateName CanonName = Context.getCanonicalTemplateName(Name);
1669 CanonType = Context.getTemplateSpecializationType(CanonName,
1673 // FIXME: CanonType is not actually the canonical type, and unfortunately
1674 // it is a TemplateSpecializationType that we will never use again.
1675 // In the future, we need to teach getTemplateSpecializationType to only
1676 // build the canonical type and return that to us.
1677 CanonType = Context.getCanonicalType(CanonType);
1679 // This might work out to be a current instantiation, in which
1680 // case the canonical type needs to be the InjectedClassNameType.
1682 // TODO: in theory this could be a simple hashtable lookup; most
1683 // changes to CurContext don't change the set of current
1685 if (isa<ClassTemplateDecl>(Template)) {
1686 for (DeclContext *Ctx = CurContext; Ctx; Ctx = Ctx->getLookupParent()) {
1687 // If we get out to a namespace, we're done.
1688 if (Ctx->isFileContext()) break;
1690 // If this isn't a record, keep looking.
1691 CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Ctx);
1692 if (!Record) continue;
1694 // Look for one of the two cases with InjectedClassNameTypes
1695 // and check whether it's the same template.
1696 if (!isa<ClassTemplatePartialSpecializationDecl>(Record) &&
1697 !Record->getDescribedClassTemplate())
1700 // Fetch the injected class name type and check whether its
1701 // injected type is equal to the type we just built.
1702 QualType ICNT = Context.getTypeDeclType(Record);
1703 QualType Injected = cast<InjectedClassNameType>(ICNT)
1704 ->getInjectedSpecializationType();
1706 if (CanonType != Injected->getCanonicalTypeInternal())
1709 // If so, the canonical type of this TST is the injected
1710 // class name type of the record we just found.
1711 assert(ICNT.isCanonical());
1716 } else if (ClassTemplateDecl *ClassTemplate
1717 = dyn_cast<ClassTemplateDecl>(Template)) {
1718 // Find the class template specialization declaration that
1719 // corresponds to these arguments.
1720 void *InsertPos = 0;
1721 ClassTemplateSpecializationDecl *Decl
1722 = ClassTemplate->findSpecialization(Converted.data(), Converted.size(),
1725 // This is the first time we have referenced this class template
1726 // specialization. Create the canonical declaration and add it to
1727 // the set of specializations.
1728 Decl = ClassTemplateSpecializationDecl::Create(Context,
1729 ClassTemplate->getTemplatedDecl()->getTagKind(),
1730 ClassTemplate->getDeclContext(),
1731 ClassTemplate->getLocation(),
1734 Converted.size(), 0);
1735 ClassTemplate->AddSpecialization(Decl, InsertPos);
1736 Decl->setLexicalDeclContext(CurContext);
1739 CanonType = Context.getTypeDeclType(Decl);
1740 assert(isa<RecordType>(CanonType) &&
1741 "type of non-dependent specialization is not a RecordType");
1744 // Build the fully-sugared type for this class template
1745 // specialization, which refers back to the class template
1746 // specialization we created or found.
1747 return Context.getTemplateSpecializationType(Name, TemplateArgs, CanonType);
1751 Sema::ActOnTemplateIdType(TemplateTy TemplateD, SourceLocation TemplateLoc,
1752 SourceLocation LAngleLoc,
1753 ASTTemplateArgsPtr TemplateArgsIn,
1754 SourceLocation RAngleLoc) {
1755 TemplateName Template = TemplateD.getAsVal<TemplateName>();
1757 // Translate the parser's template argument list in our AST format.
1758 TemplateArgumentListInfo TemplateArgs(LAngleLoc, RAngleLoc);
1759 translateTemplateArguments(TemplateArgsIn, TemplateArgs);
1761 QualType Result = CheckTemplateIdType(Template, TemplateLoc, TemplateArgs);
1762 TemplateArgsIn.release();
1764 if (Result.isNull())
1767 TypeSourceInfo *DI = Context.CreateTypeSourceInfo(Result);
1768 TemplateSpecializationTypeLoc TL
1769 = cast<TemplateSpecializationTypeLoc>(DI->getTypeLoc());
1770 TL.setTemplateNameLoc(TemplateLoc);
1771 TL.setLAngleLoc(LAngleLoc);
1772 TL.setRAngleLoc(RAngleLoc);
1773 for (unsigned i = 0, e = TL.getNumArgs(); i != e; ++i)
1774 TL.setArgLocInfo(i, TemplateArgs[i].getLocInfo());
1776 return CreateParsedType(Result, DI);
1779 TypeResult Sema::ActOnTagTemplateIdType(CXXScopeSpec &SS,
1780 TypeResult TypeResult,
1782 TypeSpecifierType TagSpec,
1783 SourceLocation TagLoc) {
1784 if (TypeResult.isInvalid())
1785 return ::TypeResult();
1788 QualType Type = GetTypeFromParser(TypeResult.get(), &DI);
1790 // Verify the tag specifier.
1791 TagTypeKind TagKind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec);
1793 if (const RecordType *RT = Type->getAs<RecordType>()) {
1794 RecordDecl *D = RT->getDecl();
1796 IdentifierInfo *Id = D->getIdentifier();
1797 assert(Id && "templated class must have an identifier");
1799 if (!isAcceptableTagRedeclaration(D, TagKind, TagLoc, *Id)) {
1800 Diag(TagLoc, diag::err_use_with_wrong_tag)
1802 << FixItHint::CreateReplacement(SourceRange(TagLoc), D->getKindName());
1803 Diag(D->getLocation(), diag::note_previous_use);
1807 ElaboratedTypeKeyword Keyword
1808 = TypeWithKeyword::getKeywordForTagTypeKind(TagKind);
1809 QualType ElabType = Context.getElaboratedType(Keyword, /*NNS=*/0, Type);
1811 TypeSourceInfo *ElabDI = Context.CreateTypeSourceInfo(ElabType);
1812 ElaboratedTypeLoc TL = cast<ElaboratedTypeLoc>(ElabDI->getTypeLoc());
1813 TL.setKeywordLoc(TagLoc);
1814 TL.setQualifierRange(SS.getRange());
1815 TL.getNamedTypeLoc().initializeFullCopy(DI->getTypeLoc());
1816 return CreateParsedType(ElabType, ElabDI);
1819 ExprResult Sema::BuildTemplateIdExpr(const CXXScopeSpec &SS,
1822 const TemplateArgumentListInfo &TemplateArgs) {
1823 // FIXME: Can we do any checking at this point? I guess we could check the
1824 // template arguments that we have against the template name, if the template
1825 // name refers to a single template. That's not a terribly common case,
1827 // foo<int> could identify a single function unambiguously
1828 // This approach does NOT work, since f<int>(1);
1829 // gets resolved prior to resorting to overload resolution
1830 // i.e., template<class T> void f(double);
1831 // vs template<class T, class U> void f(U);
1833 // These should be filtered out by our callers.
1834 assert(!R.empty() && "empty lookup results when building templateid");
1835 assert(!R.isAmbiguous() && "ambiguous lookup when building templateid");
1837 NestedNameSpecifier *Qualifier = 0;
1838 SourceRange QualifierRange;
1840 Qualifier = static_cast<NestedNameSpecifier*>(SS.getScopeRep());
1841 QualifierRange = SS.getRange();
1844 // We don't want lookup warnings at this point.
1845 R.suppressDiagnostics();
1847 UnresolvedLookupExpr *ULE
1848 = UnresolvedLookupExpr::Create(Context, R.getNamingClass(),
1849 Qualifier, QualifierRange,
1850 R.getLookupNameInfo(),
1851 RequiresADL, TemplateArgs,
1852 R.begin(), R.end());
1857 // We actually only call this from template instantiation.
1859 Sema::BuildQualifiedTemplateIdExpr(CXXScopeSpec &SS,
1860 const DeclarationNameInfo &NameInfo,
1861 const TemplateArgumentListInfo &TemplateArgs) {
1863 if (!(DC = computeDeclContext(SS, false)) ||
1864 DC->isDependentContext() ||
1865 RequireCompleteDeclContext(SS, DC))
1866 return BuildDependentDeclRefExpr(SS, NameInfo, &TemplateArgs);
1868 bool MemberOfUnknownSpecialization;
1869 LookupResult R(*this, NameInfo, LookupOrdinaryName);
1870 LookupTemplateName(R, (Scope*) 0, SS, QualType(), /*Entering*/ false,
1871 MemberOfUnknownSpecialization);
1873 if (R.isAmbiguous())
1877 Diag(NameInfo.getLoc(), diag::err_template_kw_refers_to_non_template)
1878 << NameInfo.getName() << SS.getRange();
1882 if (ClassTemplateDecl *Temp = R.getAsSingle<ClassTemplateDecl>()) {
1883 Diag(NameInfo.getLoc(), diag::err_template_kw_refers_to_class_template)
1884 << (NestedNameSpecifier*) SS.getScopeRep()
1885 << NameInfo.getName() << SS.getRange();
1886 Diag(Temp->getLocation(), diag::note_referenced_class_template);
1890 return BuildTemplateIdExpr(SS, R, /* ADL */ false, TemplateArgs);
1893 /// \brief Form a dependent template name.
1895 /// This action forms a dependent template name given the template
1896 /// name and its (presumably dependent) scope specifier. For
1897 /// example, given "MetaFun::template apply", the scope specifier \p
1898 /// SS will be "MetaFun::", \p TemplateKWLoc contains the location
1899 /// of the "template" keyword, and "apply" is the \p Name.
1900 TemplateNameKind Sema::ActOnDependentTemplateName(Scope *S,
1901 SourceLocation TemplateKWLoc,
1903 UnqualifiedId &Name,
1904 ParsedType ObjectType,
1905 bool EnteringContext,
1906 TemplateTy &Result) {
1907 if (TemplateKWLoc.isValid() && S && !S->getTemplateParamParent() &&
1908 !getLangOptions().CPlusPlus0x)
1909 Diag(TemplateKWLoc, diag::ext_template_outside_of_template)
1910 << FixItHint::CreateRemoval(TemplateKWLoc);
1912 DeclContext *LookupCtx = 0;
1914 LookupCtx = computeDeclContext(SS, EnteringContext);
1915 if (!LookupCtx && ObjectType)
1916 LookupCtx = computeDeclContext(ObjectType.get());
1918 // C++0x [temp.names]p5:
1919 // If a name prefixed by the keyword template is not the name of
1920 // a template, the program is ill-formed. [Note: the keyword
1921 // template may not be applied to non-template members of class
1922 // templates. -end note ] [ Note: as is the case with the
1923 // typename prefix, the template prefix is allowed in cases
1924 // where it is not strictly necessary; i.e., when the
1925 // nested-name-specifier or the expression on the left of the ->
1926 // or . is not dependent on a template-parameter, or the use
1927 // does not appear in the scope of a template. -end note]
1929 // Note: C++03 was more strict here, because it banned the use of
1930 // the "template" keyword prior to a template-name that was not a
1931 // dependent name. C++ DR468 relaxed this requirement (the
1932 // "template" keyword is now permitted). We follow the C++0x
1933 // rules, even in C++03 mode with a warning, retroactively applying the DR.
1934 bool MemberOfUnknownSpecialization;
1935 TemplateNameKind TNK = isTemplateName(0, SS, TemplateKWLoc.isValid(), Name,
1936 ObjectType, EnteringContext, Result,
1937 MemberOfUnknownSpecialization);
1938 if (TNK == TNK_Non_template && LookupCtx->isDependentContext() &&
1939 isa<CXXRecordDecl>(LookupCtx) &&
1940 cast<CXXRecordDecl>(LookupCtx)->hasAnyDependentBases()) {
1941 // This is a dependent template. Handle it below.
1942 } else if (TNK == TNK_Non_template) {
1943 Diag(Name.getSourceRange().getBegin(),
1944 diag::err_template_kw_refers_to_non_template)
1945 << GetNameFromUnqualifiedId(Name).getName()
1946 << Name.getSourceRange()
1948 return TNK_Non_template;
1950 // We found something; return it.
1955 NestedNameSpecifier *Qualifier
1956 = static_cast<NestedNameSpecifier *>(SS.getScopeRep());
1958 switch (Name.getKind()) {
1959 case UnqualifiedId::IK_Identifier:
1960 Result = TemplateTy::make(Context.getDependentTemplateName(Qualifier,
1962 return TNK_Dependent_template_name;
1964 case UnqualifiedId::IK_OperatorFunctionId:
1965 Result = TemplateTy::make(Context.getDependentTemplateName(Qualifier,
1966 Name.OperatorFunctionId.Operator));
1967 return TNK_Dependent_template_name;
1969 case UnqualifiedId::IK_LiteralOperatorId:
1970 assert(false && "We don't support these; Parse shouldn't have allowed propagation");
1976 Diag(Name.getSourceRange().getBegin(),
1977 diag::err_template_kw_refers_to_non_template)
1978 << GetNameFromUnqualifiedId(Name).getName()
1979 << Name.getSourceRange()
1981 return TNK_Non_template;
1984 bool Sema::CheckTemplateTypeArgument(TemplateTypeParmDecl *Param,
1985 const TemplateArgumentLoc &AL,
1986 llvm::SmallVectorImpl<TemplateArgument> &Converted) {
1987 const TemplateArgument &Arg = AL.getArgument();
1989 // Check template type parameter.
1990 switch(Arg.getKind()) {
1991 case TemplateArgument::Type:
1992 // C++ [temp.arg.type]p1:
1993 // A template-argument for a template-parameter which is a
1994 // type shall be a type-id.
1996 case TemplateArgument::Template: {
1997 // We have a template type parameter but the template argument
1998 // is a template without any arguments.
1999 SourceRange SR = AL.getSourceRange();
2000 TemplateName Name = Arg.getAsTemplate();
2001 Diag(SR.getBegin(), diag::err_template_missing_args)
2003 if (TemplateDecl *Decl = Name.getAsTemplateDecl())
2004 Diag(Decl->getLocation(), diag::note_template_decl_here);
2009 // We have a template type parameter but the template argument
2011 SourceRange SR = AL.getSourceRange();
2012 Diag(SR.getBegin(), diag::err_template_arg_must_be_type) << SR;
2013 Diag(Param->getLocation(), diag::note_template_param_here);
2019 if (CheckTemplateArgument(Param, AL.getTypeSourceInfo()))
2022 // Add the converted template type argument.
2023 Converted.push_back(
2024 TemplateArgument(Context.getCanonicalType(Arg.getAsType())));
2028 /// \brief Substitute template arguments into the default template argument for
2029 /// the given template type parameter.
2031 /// \param SemaRef the semantic analysis object for which we are performing
2032 /// the substitution.
2034 /// \param Template the template that we are synthesizing template arguments
2037 /// \param TemplateLoc the location of the template name that started the
2038 /// template-id we are checking.
2040 /// \param RAngleLoc the location of the right angle bracket ('>') that
2041 /// terminates the template-id.
2043 /// \param Param the template template parameter whose default we are
2044 /// substituting into.
2046 /// \param Converted the list of template arguments provided for template
2047 /// parameters that precede \p Param in the template parameter list.
2049 /// \returns the substituted template argument, or NULL if an error occurred.
2050 static TypeSourceInfo *
2051 SubstDefaultTemplateArgument(Sema &SemaRef,
2052 TemplateDecl *Template,
2053 SourceLocation TemplateLoc,
2054 SourceLocation RAngleLoc,
2055 TemplateTypeParmDecl *Param,
2056 llvm::SmallVectorImpl<TemplateArgument> &Converted) {
2057 TypeSourceInfo *ArgType = Param->getDefaultArgumentInfo();
2059 // If the argument type is dependent, instantiate it now based
2060 // on the previously-computed template arguments.
2061 if (ArgType->getType()->isDependentType()) {
2062 TemplateArgumentList TemplateArgs(TemplateArgumentList::OnStack,
2063 Converted.data(), Converted.size());
2065 MultiLevelTemplateArgumentList AllTemplateArgs
2066 = SemaRef.getTemplateInstantiationArgs(Template, &TemplateArgs);
2068 Sema::InstantiatingTemplate Inst(SemaRef, TemplateLoc,
2069 Template, Converted.data(),
2071 SourceRange(TemplateLoc, RAngleLoc));
2073 ArgType = SemaRef.SubstType(ArgType, AllTemplateArgs,
2074 Param->getDefaultArgumentLoc(),
2075 Param->getDeclName());
2081 /// \brief Substitute template arguments into the default template argument for
2082 /// the given non-type template parameter.
2084 /// \param SemaRef the semantic analysis object for which we are performing
2085 /// the substitution.
2087 /// \param Template the template that we are synthesizing template arguments
2090 /// \param TemplateLoc the location of the template name that started the
2091 /// template-id we are checking.
2093 /// \param RAngleLoc the location of the right angle bracket ('>') that
2094 /// terminates the template-id.
2096 /// \param Param the non-type template parameter whose default we are
2097 /// substituting into.
2099 /// \param Converted the list of template arguments provided for template
2100 /// parameters that precede \p Param in the template parameter list.
2102 /// \returns the substituted template argument, or NULL if an error occurred.
2104 SubstDefaultTemplateArgument(Sema &SemaRef,
2105 TemplateDecl *Template,
2106 SourceLocation TemplateLoc,
2107 SourceLocation RAngleLoc,
2108 NonTypeTemplateParmDecl *Param,
2109 llvm::SmallVectorImpl<TemplateArgument> &Converted) {
2110 TemplateArgumentList TemplateArgs(TemplateArgumentList::OnStack,
2111 Converted.data(), Converted.size());
2113 MultiLevelTemplateArgumentList AllTemplateArgs
2114 = SemaRef.getTemplateInstantiationArgs(Template, &TemplateArgs);
2116 Sema::InstantiatingTemplate Inst(SemaRef, TemplateLoc,
2117 Template, Converted.data(),
2119 SourceRange(TemplateLoc, RAngleLoc));
2121 return SemaRef.SubstExpr(Param->getDefaultArgument(), AllTemplateArgs);
2124 /// \brief Substitute template arguments into the default template argument for
2125 /// the given template template parameter.
2127 /// \param SemaRef the semantic analysis object for which we are performing
2128 /// the substitution.
2130 /// \param Template the template that we are synthesizing template arguments
2133 /// \param TemplateLoc the location of the template name that started the
2134 /// template-id we are checking.
2136 /// \param RAngleLoc the location of the right angle bracket ('>') that
2137 /// terminates the template-id.
2139 /// \param Param the template template parameter whose default we are
2140 /// substituting into.
2142 /// \param Converted the list of template arguments provided for template
2143 /// parameters that precede \p Param in the template parameter list.
2145 /// \returns the substituted template argument, or NULL if an error occurred.
2147 SubstDefaultTemplateArgument(Sema &SemaRef,
2148 TemplateDecl *Template,
2149 SourceLocation TemplateLoc,
2150 SourceLocation RAngleLoc,
2151 TemplateTemplateParmDecl *Param,
2152 llvm::SmallVectorImpl<TemplateArgument> &Converted) {
2153 TemplateArgumentList TemplateArgs(TemplateArgumentList::OnStack,
2154 Converted.data(), Converted.size());
2156 MultiLevelTemplateArgumentList AllTemplateArgs
2157 = SemaRef.getTemplateInstantiationArgs(Template, &TemplateArgs);
2159 Sema::InstantiatingTemplate Inst(SemaRef, TemplateLoc,
2160 Template, Converted.data(),
2162 SourceRange(TemplateLoc, RAngleLoc));
2164 return SemaRef.SubstTemplateName(
2165 Param->getDefaultArgument().getArgument().getAsTemplate(),
2166 Param->getDefaultArgument().getTemplateNameLoc(),
2170 /// \brief If the given template parameter has a default template
2171 /// argument, substitute into that default template argument and
2172 /// return the corresponding template argument.
2174 Sema::SubstDefaultTemplateArgumentIfAvailable(TemplateDecl *Template,
2175 SourceLocation TemplateLoc,
2176 SourceLocation RAngleLoc,
2178 llvm::SmallVectorImpl<TemplateArgument> &Converted) {
2179 if (TemplateTypeParmDecl *TypeParm = dyn_cast<TemplateTypeParmDecl>(Param)) {
2180 if (!TypeParm->hasDefaultArgument())
2181 return TemplateArgumentLoc();
2183 TypeSourceInfo *DI = SubstDefaultTemplateArgument(*this, Template,
2189 return TemplateArgumentLoc(TemplateArgument(DI->getType()), DI);
2191 return TemplateArgumentLoc();
2194 if (NonTypeTemplateParmDecl *NonTypeParm
2195 = dyn_cast<NonTypeTemplateParmDecl>(Param)) {
2196 if (!NonTypeParm->hasDefaultArgument())
2197 return TemplateArgumentLoc();
2199 ExprResult Arg = SubstDefaultTemplateArgument(*this, Template,
2204 if (Arg.isInvalid())
2205 return TemplateArgumentLoc();
2207 Expr *ArgE = Arg.takeAs<Expr>();
2208 return TemplateArgumentLoc(TemplateArgument(ArgE), ArgE);
2211 TemplateTemplateParmDecl *TempTempParm
2212 = cast<TemplateTemplateParmDecl>(Param);
2213 if (!TempTempParm->hasDefaultArgument())
2214 return TemplateArgumentLoc();
2216 TemplateName TName = SubstDefaultTemplateArgument(*this, Template,
2222 return TemplateArgumentLoc();
2224 return TemplateArgumentLoc(TemplateArgument(TName),
2225 TempTempParm->getDefaultArgument().getTemplateQualifierRange(),
2226 TempTempParm->getDefaultArgument().getTemplateNameLoc());
2229 /// \brief Check that the given template argument corresponds to the given
2230 /// template parameter.
2232 /// \param Param The template parameter against which the argument will be
2235 /// \param Arg The template argument.
2237 /// \param Template The template in which the template argument resides.
2239 /// \param TemplateLoc The location of the template name for the template
2240 /// whose argument list we're matching.
2242 /// \param RAngleLoc The location of the right angle bracket ('>') that closes
2243 /// the template argument list.
2245 /// \param ArgumentPackIndex The index into the argument pack where this
2246 /// argument will be placed. Only valid if the parameter is a parameter pack.
2248 /// \param Converted The checked, converted argument will be added to the
2249 /// end of this small vector.
2251 /// \param CTAK Describes how we arrived at this particular template argument:
2252 /// explicitly written, deduced, etc.
2254 /// \returns true on error, false otherwise.
2255 bool Sema::CheckTemplateArgument(NamedDecl *Param,
2256 const TemplateArgumentLoc &Arg,
2257 NamedDecl *Template,
2258 SourceLocation TemplateLoc,
2259 SourceLocation RAngleLoc,
2260 unsigned ArgumentPackIndex,
2261 llvm::SmallVectorImpl<TemplateArgument> &Converted,
2262 CheckTemplateArgumentKind CTAK) {
2263 // Check template type parameters.
2264 if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(Param))
2265 return CheckTemplateTypeArgument(TTP, Arg, Converted);
2267 // Check non-type template parameters.
2268 if (NonTypeTemplateParmDecl *NTTP =dyn_cast<NonTypeTemplateParmDecl>(Param)) {
2269 // Do substitution on the type of the non-type template parameter
2270 // with the template arguments we've seen thus far. But if the
2271 // template has a dependent context then we cannot substitute yet.
2272 QualType NTTPType = NTTP->getType();
2273 if (NTTP->isParameterPack() && NTTP->isExpandedParameterPack())
2274 NTTPType = NTTP->getExpansionType(ArgumentPackIndex);
2276 if (NTTPType->isDependentType() &&
2277 !isa<TemplateTemplateParmDecl>(Template) &&
2278 !Template->getDeclContext()->isDependentContext()) {
2279 // Do substitution on the type of the non-type template parameter.
2280 InstantiatingTemplate Inst(*this, TemplateLoc, Template,
2281 NTTP, Converted.data(), Converted.size(),
2282 SourceRange(TemplateLoc, RAngleLoc));
2284 TemplateArgumentList TemplateArgs(TemplateArgumentList::OnStack,
2285 Converted.data(), Converted.size());
2286 NTTPType = SubstType(NTTPType,
2287 MultiLevelTemplateArgumentList(TemplateArgs),
2288 NTTP->getLocation(),
2289 NTTP->getDeclName());
2290 // If that worked, check the non-type template parameter type
2292 if (!NTTPType.isNull())
2293 NTTPType = CheckNonTypeTemplateParameterType(NTTPType,
2294 NTTP->getLocation());
2295 if (NTTPType.isNull())
2299 switch (Arg.getArgument().getKind()) {
2300 case TemplateArgument::Null:
2301 assert(false && "Should never see a NULL template argument here");
2304 case TemplateArgument::Expression: {
2305 Expr *E = Arg.getArgument().getAsExpr();
2306 TemplateArgument Result;
2307 if (CheckTemplateArgument(NTTP, NTTPType, E, Result, CTAK))
2310 Converted.push_back(Result);
2314 case TemplateArgument::Declaration:
2315 case TemplateArgument::Integral:
2316 // We've already checked this template argument, so just copy
2317 // it to the list of converted arguments.
2318 Converted.push_back(Arg.getArgument());
2321 case TemplateArgument::Template:
2322 case TemplateArgument::TemplateExpansion:
2323 // We were given a template template argument. It may not be ill-formed;
2325 if (DependentTemplateName *DTN
2326 = Arg.getArgument().getAsTemplateOrTemplatePattern()
2327 .getAsDependentTemplateName()) {
2328 // We have a template argument such as \c T::template X, which we
2329 // parsed as a template template argument. However, since we now
2330 // know that we need a non-type template argument, convert this
2331 // template name into an expression.
2333 DeclarationNameInfo NameInfo(DTN->getIdentifier(),
2334 Arg.getTemplateNameLoc());
2336 Expr *E = DependentScopeDeclRefExpr::Create(Context,
2337 DTN->getQualifier(),
2338 Arg.getTemplateQualifierRange(),
2341 // If we parsed the template argument as a pack expansion, create a
2342 // pack expansion expression.
2343 if (Arg.getArgument().getKind() == TemplateArgument::TemplateExpansion){
2344 ExprResult Expansion = ActOnPackExpansion(E,
2345 Arg.getTemplateEllipsisLoc());
2346 if (Expansion.isInvalid())
2349 E = Expansion.get();
2352 TemplateArgument Result;
2353 if (CheckTemplateArgument(NTTP, NTTPType, E, Result))
2356 Converted.push_back(Result);
2360 // We have a template argument that actually does refer to a class
2361 // template, template alias, or template template parameter, and
2362 // therefore cannot be a non-type template argument.
2363 Diag(Arg.getLocation(), diag::err_template_arg_must_be_expr)
2364 << Arg.getSourceRange();
2366 Diag(Param->getLocation(), diag::note_template_param_here);
2369 case TemplateArgument::Type: {
2370 // We have a non-type template parameter but the template
2371 // argument is a type.
2373 // C++ [temp.arg]p2:
2374 // In a template-argument, an ambiguity between a type-id and
2375 // an expression is resolved to a type-id, regardless of the
2376 // form of the corresponding template-parameter.
2378 // We warn specifically about this case, since it can be rather
2379 // confusing for users.
2380 QualType T = Arg.getArgument().getAsType();
2381 SourceRange SR = Arg.getSourceRange();
2382 if (T->isFunctionType())
2383 Diag(SR.getBegin(), diag::err_template_arg_nontype_ambig) << SR << T;
2385 Diag(SR.getBegin(), diag::err_template_arg_must_be_expr) << SR;
2386 Diag(Param->getLocation(), diag::note_template_param_here);
2390 case TemplateArgument::Pack:
2391 llvm_unreachable("Caller must expand template argument packs");
2399 // Check template template parameters.
2400 TemplateTemplateParmDecl *TempParm = cast<TemplateTemplateParmDecl>(Param);
2402 // Substitute into the template parameter list of the template
2403 // template parameter, since previously-supplied template arguments
2404 // may appear within the template template parameter.
2406 // Set up a template instantiation context.
2407 LocalInstantiationScope Scope(*this);
2408 InstantiatingTemplate Inst(*this, TemplateLoc, Template,
2409 TempParm, Converted.data(), Converted.size(),
2410 SourceRange(TemplateLoc, RAngleLoc));
2412 TemplateArgumentList TemplateArgs(TemplateArgumentList::OnStack,
2413 Converted.data(), Converted.size());
2414 TempParm = cast_or_null<TemplateTemplateParmDecl>(
2415 SubstDecl(TempParm, CurContext,
2416 MultiLevelTemplateArgumentList(TemplateArgs)));
2421 switch (Arg.getArgument().getKind()) {
2422 case TemplateArgument::Null:
2423 assert(false && "Should never see a NULL template argument here");
2426 case TemplateArgument::Template:
2427 case TemplateArgument::TemplateExpansion:
2428 if (CheckTemplateArgument(TempParm, Arg))
2431 Converted.push_back(Arg.getArgument());
2434 case TemplateArgument::Expression:
2435 case TemplateArgument::Type:
2436 // We have a template template parameter but the template
2437 // argument does not refer to a template.
2438 Diag(Arg.getLocation(), diag::err_template_arg_must_be_template);
2441 case TemplateArgument::Declaration:
2443 "Declaration argument with template template parameter");
2445 case TemplateArgument::Integral:
2447 "Integral argument with template template parameter");
2450 case TemplateArgument::Pack:
2451 llvm_unreachable("Caller must expand template argument packs");
2458 /// \brief Check that the given template argument list is well-formed
2459 /// for specializing the given template.
2460 bool Sema::CheckTemplateArgumentList(TemplateDecl *Template,
2461 SourceLocation TemplateLoc,
2462 const TemplateArgumentListInfo &TemplateArgs,
2463 bool PartialTemplateArgs,
2464 llvm::SmallVectorImpl<TemplateArgument> &Converted) {
2465 TemplateParameterList *Params = Template->getTemplateParameters();
2466 unsigned NumParams = Params->size();
2467 unsigned NumArgs = TemplateArgs.size();
2468 bool Invalid = false;
2470 SourceLocation RAngleLoc = TemplateArgs.getRAngleLoc();
2472 bool HasParameterPack =
2473 NumParams > 0 && Params->getParam(NumParams - 1)->isTemplateParameterPack();
2475 if ((NumArgs > NumParams && !HasParameterPack) ||
2476 (NumArgs < Params->getMinRequiredArguments() &&
2477 !PartialTemplateArgs)) {
2478 // FIXME: point at either the first arg beyond what we can handle,
2479 // or the '>', depending on whether we have too many or too few
2482 if (NumArgs > NumParams)
2483 Range = SourceRange(TemplateArgs[NumParams].getLocation(), RAngleLoc);
2484 Diag(TemplateLoc, diag::err_template_arg_list_different_arity)
2485 << (NumArgs > NumParams)
2486 << (isa<ClassTemplateDecl>(Template)? 0 :
2487 isa<FunctionTemplateDecl>(Template)? 1 :
2488 isa<TemplateTemplateParmDecl>(Template)? 2 : 3)
2489 << Template << Range;
2490 Diag(Template->getLocation(), diag::note_template_decl_here)
2491 << Params->getSourceRange();
2495 // C++ [temp.arg]p1:
2496 // [...] The type and form of each template-argument specified in
2497 // a template-id shall match the type and form specified for the
2498 // corresponding parameter declared by the template in its
2499 // template-parameter-list.
2500 llvm::SmallVector<TemplateArgument, 2> ArgumentPack;
2501 TemplateParameterList::iterator Param = Params->begin(),
2502 ParamEnd = Params->end();
2503 unsigned ArgIdx = 0;
2504 LocalInstantiationScope InstScope(*this, true);
2505 while (Param != ParamEnd) {
2506 if (ArgIdx > NumArgs && PartialTemplateArgs)
2509 if (ArgIdx < NumArgs) {
2510 // If we have an expanded parameter pack, make sure we don't have too
2512 if (NonTypeTemplateParmDecl *NTTP
2513 = dyn_cast<NonTypeTemplateParmDecl>(*Param)) {
2514 if (NTTP->isExpandedParameterPack() &&
2515 ArgumentPack.size() >= NTTP->getNumExpansionTypes()) {
2516 Diag(TemplateLoc, diag::err_template_arg_list_different_arity)
2518 << (isa<ClassTemplateDecl>(Template)? 0 :
2519 isa<FunctionTemplateDecl>(Template)? 1 :
2520 isa<TemplateTemplateParmDecl>(Template)? 2 : 3)
2522 Diag(Template->getLocation(), diag::note_template_decl_here)
2523 << Params->getSourceRange();
2528 // Check the template argument we were given.
2529 if (CheckTemplateArgument(*Param, TemplateArgs[ArgIdx], Template,
2530 TemplateLoc, RAngleLoc,
2531 ArgumentPack.size(), Converted))
2534 if ((*Param)->isTemplateParameterPack()) {
2535 // The template parameter was a template parameter pack, so take the
2536 // deduced argument and place it on the argument pack. Note that we
2537 // stay on the same template parameter so that we can deduce more
2539 ArgumentPack.push_back(Converted.back());
2540 Converted.pop_back();
2542 // Move to the next template parameter.
2549 // If we have a template parameter pack with no more corresponding
2550 // arguments, just break out now and we'll fill in the argument pack below.
2551 if ((*Param)->isTemplateParameterPack())
2554 // We have a default template argument that we will use.
2555 TemplateArgumentLoc Arg;
2557 // Retrieve the default template argument from the template
2558 // parameter. For each kind of template parameter, we substitute the
2559 // template arguments provided thus far and any "outer" template arguments
2560 // (when the template parameter was part of a nested template) into
2561 // the default argument.
2562 if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(*Param)) {
2563 if (!TTP->hasDefaultArgument()) {
2564 assert((Invalid || PartialTemplateArgs) && "Missing default argument");
2568 TypeSourceInfo *ArgType = SubstDefaultTemplateArgument(*this,
2577 Arg = TemplateArgumentLoc(TemplateArgument(ArgType->getType()),
2579 } else if (NonTypeTemplateParmDecl *NTTP
2580 = dyn_cast<NonTypeTemplateParmDecl>(*Param)) {
2581 if (!NTTP->hasDefaultArgument()) {
2582 assert((Invalid || PartialTemplateArgs) && "Missing default argument");
2586 ExprResult E = SubstDefaultTemplateArgument(*this, Template,
2594 Expr *Ex = E.takeAs<Expr>();
2595 Arg = TemplateArgumentLoc(TemplateArgument(Ex), Ex);
2597 TemplateTemplateParmDecl *TempParm
2598 = cast<TemplateTemplateParmDecl>(*Param);
2600 if (!TempParm->hasDefaultArgument()) {
2601 assert((Invalid || PartialTemplateArgs) && "Missing default argument");
2605 TemplateName Name = SubstDefaultTemplateArgument(*this, Template,
2613 Arg = TemplateArgumentLoc(TemplateArgument(Name),
2614 TempParm->getDefaultArgument().getTemplateQualifierRange(),
2615 TempParm->getDefaultArgument().getTemplateNameLoc());
2618 // Introduce an instantiation record that describes where we are using
2619 // the default template argument.
2620 InstantiatingTemplate Instantiating(*this, RAngleLoc, Template, *Param,
2621 Converted.data(), Converted.size(),
2622 SourceRange(TemplateLoc, RAngleLoc));
2624 // Check the default template argument.
2625 if (CheckTemplateArgument(*Param, Arg, Template, TemplateLoc,
2626 RAngleLoc, 0, Converted))
2629 // Move to the next template parameter and argument.
2634 // Form argument packs for each of the parameter packs remaining.
2635 while (Param != ParamEnd) {
2636 // If we're checking a partial list of template arguments, don't fill
2637 // in arguments for non-template parameter packs.
2639 if ((*Param)->isTemplateParameterPack()) {
2640 if (PartialTemplateArgs && ArgumentPack.empty()) {
2641 Converted.push_back(TemplateArgument());
2642 } else if (ArgumentPack.empty())
2643 Converted.push_back(TemplateArgument(0, 0));
2645 Converted.push_back(TemplateArgument::CreatePackCopy(Context,
2646 ArgumentPack.data(),
2647 ArgumentPack.size()));
2648 ArgumentPack.clear();
2659 class UnnamedLocalNoLinkageFinder
2660 : public TypeVisitor<UnnamedLocalNoLinkageFinder, bool>
2665 typedef TypeVisitor<UnnamedLocalNoLinkageFinder, bool> inherited;
2668 UnnamedLocalNoLinkageFinder(Sema &S, SourceRange SR) : S(S), SR(SR) { }
2670 bool Visit(QualType T) {
2671 return inherited::Visit(T.getTypePtr());
2674 #define TYPE(Class, Parent) \
2675 bool Visit##Class##Type(const Class##Type *);
2676 #define ABSTRACT_TYPE(Class, Parent) \
2677 bool Visit##Class##Type(const Class##Type *) { return false; }
2678 #define NON_CANONICAL_TYPE(Class, Parent) \
2679 bool Visit##Class##Type(const Class##Type *) { return false; }
2680 #include "clang/AST/TypeNodes.def"
2682 bool VisitTagDecl(const TagDecl *Tag);
2683 bool VisitNestedNameSpecifier(NestedNameSpecifier *NNS);
2687 bool UnnamedLocalNoLinkageFinder::VisitBuiltinType(const BuiltinType*) {
2691 bool UnnamedLocalNoLinkageFinder::VisitComplexType(const ComplexType* T) {
2692 return Visit(T->getElementType());
2695 bool UnnamedLocalNoLinkageFinder::VisitPointerType(const PointerType* T) {
2696 return Visit(T->getPointeeType());
2699 bool UnnamedLocalNoLinkageFinder::VisitBlockPointerType(
2700 const BlockPointerType* T) {
2701 return Visit(T->getPointeeType());
2704 bool UnnamedLocalNoLinkageFinder::VisitLValueReferenceType(
2705 const LValueReferenceType* T) {
2706 return Visit(T->getPointeeType());
2709 bool UnnamedLocalNoLinkageFinder::VisitRValueReferenceType(
2710 const RValueReferenceType* T) {
2711 return Visit(T->getPointeeType());
2714 bool UnnamedLocalNoLinkageFinder::VisitMemberPointerType(
2715 const MemberPointerType* T) {
2716 return Visit(T->getPointeeType()) || Visit(QualType(T->getClass(), 0));
2719 bool UnnamedLocalNoLinkageFinder::VisitConstantArrayType(
2720 const ConstantArrayType* T) {
2721 return Visit(T->getElementType());
2724 bool UnnamedLocalNoLinkageFinder::VisitIncompleteArrayType(
2725 const IncompleteArrayType* T) {
2726 return Visit(T->getElementType());
2729 bool UnnamedLocalNoLinkageFinder::VisitVariableArrayType(
2730 const VariableArrayType* T) {
2731 return Visit(T->getElementType());
2734 bool UnnamedLocalNoLinkageFinder::VisitDependentSizedArrayType(
2735 const DependentSizedArrayType* T) {
2736 return Visit(T->getElementType());
2739 bool UnnamedLocalNoLinkageFinder::VisitDependentSizedExtVectorType(
2740 const DependentSizedExtVectorType* T) {
2741 return Visit(T->getElementType());
2744 bool UnnamedLocalNoLinkageFinder::VisitVectorType(const VectorType* T) {
2745 return Visit(T->getElementType());
2748 bool UnnamedLocalNoLinkageFinder::VisitExtVectorType(const ExtVectorType* T) {
2749 return Visit(T->getElementType());
2752 bool UnnamedLocalNoLinkageFinder::VisitFunctionProtoType(
2753 const FunctionProtoType* T) {
2754 for (FunctionProtoType::arg_type_iterator A = T->arg_type_begin(),
2755 AEnd = T->arg_type_end();
2761 return Visit(T->getResultType());
2764 bool UnnamedLocalNoLinkageFinder::VisitFunctionNoProtoType(
2765 const FunctionNoProtoType* T) {
2766 return Visit(T->getResultType());
2769 bool UnnamedLocalNoLinkageFinder::VisitUnresolvedUsingType(
2770 const UnresolvedUsingType*) {
2774 bool UnnamedLocalNoLinkageFinder::VisitTypeOfExprType(const TypeOfExprType*) {
2778 bool UnnamedLocalNoLinkageFinder::VisitTypeOfType(const TypeOfType* T) {
2779 return Visit(T->getUnderlyingType());
2782 bool UnnamedLocalNoLinkageFinder::VisitDecltypeType(const DecltypeType*) {
2786 bool UnnamedLocalNoLinkageFinder::VisitAutoType(const AutoType *T) {
2787 return Visit(T->getDeducedType());
2790 bool UnnamedLocalNoLinkageFinder::VisitRecordType(const RecordType* T) {
2791 return VisitTagDecl(T->getDecl());
2794 bool UnnamedLocalNoLinkageFinder::VisitEnumType(const EnumType* T) {
2795 return VisitTagDecl(T->getDecl());
2798 bool UnnamedLocalNoLinkageFinder::VisitTemplateTypeParmType(
2799 const TemplateTypeParmType*) {
2803 bool UnnamedLocalNoLinkageFinder::VisitSubstTemplateTypeParmPackType(
2804 const SubstTemplateTypeParmPackType *) {
2808 bool UnnamedLocalNoLinkageFinder::VisitTemplateSpecializationType(
2809 const TemplateSpecializationType*) {
2813 bool UnnamedLocalNoLinkageFinder::VisitInjectedClassNameType(
2814 const InjectedClassNameType* T) {
2815 return VisitTagDecl(T->getDecl());
2818 bool UnnamedLocalNoLinkageFinder::VisitDependentNameType(
2819 const DependentNameType* T) {
2820 return VisitNestedNameSpecifier(T->getQualifier());
2823 bool UnnamedLocalNoLinkageFinder::VisitDependentTemplateSpecializationType(
2824 const DependentTemplateSpecializationType* T) {
2825 return VisitNestedNameSpecifier(T->getQualifier());
2828 bool UnnamedLocalNoLinkageFinder::VisitPackExpansionType(
2829 const PackExpansionType* T) {
2830 return Visit(T->getPattern());
2833 bool UnnamedLocalNoLinkageFinder::VisitObjCObjectType(const ObjCObjectType *) {
2837 bool UnnamedLocalNoLinkageFinder::VisitObjCInterfaceType(
2838 const ObjCInterfaceType *) {
2842 bool UnnamedLocalNoLinkageFinder::VisitObjCObjectPointerType(
2843 const ObjCObjectPointerType *) {
2847 bool UnnamedLocalNoLinkageFinder::VisitTagDecl(const TagDecl *Tag) {
2848 if (Tag->getDeclContext()->isFunctionOrMethod()) {
2849 S.Diag(SR.getBegin(), diag::ext_template_arg_local_type)
2850 << S.Context.getTypeDeclType(Tag) << SR;
2854 if (!Tag->getDeclName() && !Tag->getTypedefForAnonDecl()) {
2855 S.Diag(SR.getBegin(), diag::ext_template_arg_unnamed_type) << SR;
2856 S.Diag(Tag->getLocation(), diag::note_template_unnamed_type_here);
2863 bool UnnamedLocalNoLinkageFinder::VisitNestedNameSpecifier(
2864 NestedNameSpecifier *NNS) {
2865 if (NNS->getPrefix() && VisitNestedNameSpecifier(NNS->getPrefix()))
2868 switch (NNS->getKind()) {
2869 case NestedNameSpecifier::Identifier:
2870 case NestedNameSpecifier::Namespace:
2871 case NestedNameSpecifier::Global:
2874 case NestedNameSpecifier::TypeSpec:
2875 case NestedNameSpecifier::TypeSpecWithTemplate:
2876 return Visit(QualType(NNS->getAsType(), 0));
2882 /// \brief Check a template argument against its corresponding
2883 /// template type parameter.
2885 /// This routine implements the semantics of C++ [temp.arg.type]. It
2886 /// returns true if an error occurred, and false otherwise.
2887 bool Sema::CheckTemplateArgument(TemplateTypeParmDecl *Param,
2888 TypeSourceInfo *ArgInfo) {
2889 assert(ArgInfo && "invalid TypeSourceInfo");
2890 QualType Arg = ArgInfo->getType();
2891 SourceRange SR = ArgInfo->getTypeLoc().getSourceRange();
2893 if (Arg->isVariablyModifiedType()) {
2894 return Diag(SR.getBegin(), diag::err_variably_modified_template_arg) << Arg;
2895 } else if (Context.hasSameUnqualifiedType(Arg, Context.OverloadTy)) {
2896 return Diag(SR.getBegin(), diag::err_template_arg_overload_type) << SR;
2899 // C++03 [temp.arg.type]p2:
2900 // A local type, a type with no linkage, an unnamed type or a type
2901 // compounded from any of these types shall not be used as a
2902 // template-argument for a template type-parameter.
2904 // C++0x allows these, and even in C++03 we allow them as an extension with
2906 if (!LangOpts.CPlusPlus0x && Arg->hasUnnamedOrLocalType()) {
2907 UnnamedLocalNoLinkageFinder Finder(*this, SR);
2908 (void)Finder.Visit(Context.getCanonicalType(Arg));
2914 /// \brief Checks whether the given template argument is the address
2915 /// of an object or function according to C++ [temp.arg.nontype]p1.
2917 CheckTemplateArgumentAddressOfObjectOrFunction(Sema &S,
2918 NonTypeTemplateParmDecl *Param,
2921 TemplateArgument &Converted) {
2922 bool Invalid = false;
2924 QualType ArgType = Arg->getType();
2926 // See through any implicit casts we added to fix the type.
2927 while (ImplicitCastExpr *Cast = dyn_cast<ImplicitCastExpr>(Arg))
2928 Arg = Cast->getSubExpr();
2930 // C++ [temp.arg.nontype]p1:
2932 // A template-argument for a non-type, non-template
2933 // template-parameter shall be one of: [...]
2935 // -- the address of an object or function with external
2936 // linkage, including function templates and function
2937 // template-ids but excluding non-static class members,
2938 // expressed as & id-expression where the & is optional if
2939 // the name refers to a function or array, or if the
2940 // corresponding template-parameter is a reference; or
2941 DeclRefExpr *DRE = 0;
2943 // In C++98/03 mode, give an extension warning on any extra parentheses.
2944 // See http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_defects.html#773
2945 bool ExtraParens = false;
2946 while (ParenExpr *Parens = dyn_cast<ParenExpr>(Arg)) {
2947 if (!Invalid && !ExtraParens && !S.getLangOptions().CPlusPlus0x) {
2948 S.Diag(Arg->getSourceRange().getBegin(),
2949 diag::ext_template_arg_extra_parens)
2950 << Arg->getSourceRange();
2954 Arg = Parens->getSubExpr();
2957 bool AddressTaken = false;
2958 SourceLocation AddrOpLoc;
2959 if (UnaryOperator *UnOp = dyn_cast<UnaryOperator>(Arg)) {
2960 if (UnOp->getOpcode() == UO_AddrOf) {
2961 DRE = dyn_cast<DeclRefExpr>(UnOp->getSubExpr());
2962 AddressTaken = true;
2963 AddrOpLoc = UnOp->getOperatorLoc();
2966 DRE = dyn_cast<DeclRefExpr>(Arg);
2969 S.Diag(Arg->getLocStart(), diag::err_template_arg_not_decl_ref)
2970 << Arg->getSourceRange();
2971 S.Diag(Param->getLocation(), diag::note_template_param_here);
2975 // Stop checking the precise nature of the argument if it is value dependent,
2976 // it should be checked when instantiated.
2977 if (Arg->isValueDependent()) {
2978 Converted = TemplateArgument(ArgIn);
2982 if (!isa<ValueDecl>(DRE->getDecl())) {
2983 S.Diag(Arg->getSourceRange().getBegin(),
2984 diag::err_template_arg_not_object_or_func_form)
2985 << Arg->getSourceRange();
2986 S.Diag(Param->getLocation(), diag::note_template_param_here);
2990 NamedDecl *Entity = 0;
2992 // Cannot refer to non-static data members
2993 if (FieldDecl *Field = dyn_cast<FieldDecl>(DRE->getDecl())) {
2994 S.Diag(Arg->getSourceRange().getBegin(), diag::err_template_arg_field)
2995 << Field << Arg->getSourceRange();
2996 S.Diag(Param->getLocation(), diag::note_template_param_here);
3000 // Cannot refer to non-static member functions
3001 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(DRE->getDecl()))
3002 if (!Method->isStatic()) {
3003 S.Diag(Arg->getSourceRange().getBegin(), diag::err_template_arg_method)
3004 << Method << Arg->getSourceRange();
3005 S.Diag(Param->getLocation(), diag::note_template_param_here);
3009 // Functions must have external linkage.
3010 if (FunctionDecl *Func = dyn_cast<FunctionDecl>(DRE->getDecl())) {
3011 if (!isExternalLinkage(Func->getLinkage())) {
3012 S.Diag(Arg->getSourceRange().getBegin(),
3013 diag::err_template_arg_function_not_extern)
3014 << Func << Arg->getSourceRange();
3015 S.Diag(Func->getLocation(), diag::note_template_arg_internal_object)
3020 // Okay: we've named a function with external linkage.
3023 // If the template parameter has pointer type, the function decays.
3024 if (ParamType->isPointerType() && !AddressTaken)
3025 ArgType = S.Context.getPointerType(Func->getType());
3026 else if (AddressTaken && ParamType->isReferenceType()) {
3027 // If we originally had an address-of operator, but the
3028 // parameter has reference type, complain and (if things look
3029 // like they will work) drop the address-of operator.
3030 if (!S.Context.hasSameUnqualifiedType(Func->getType(),
3031 ParamType.getNonReferenceType())) {
3032 S.Diag(AddrOpLoc, diag::err_template_arg_address_of_non_pointer)
3034 S.Diag(Param->getLocation(), diag::note_template_param_here);
3038 S.Diag(AddrOpLoc, diag::err_template_arg_address_of_non_pointer)
3040 << FixItHint::CreateRemoval(AddrOpLoc);
3041 S.Diag(Param->getLocation(), diag::note_template_param_here);
3043 ArgType = Func->getType();
3045 } else if (VarDecl *Var = dyn_cast<VarDecl>(DRE->getDecl())) {
3046 if (!isExternalLinkage(Var->getLinkage())) {
3047 S.Diag(Arg->getSourceRange().getBegin(),
3048 diag::err_template_arg_object_not_extern)
3049 << Var << Arg->getSourceRange();
3050 S.Diag(Var->getLocation(), diag::note_template_arg_internal_object)
3055 // A value of reference type is not an object.
3056 if (Var->getType()->isReferenceType()) {
3057 S.Diag(Arg->getSourceRange().getBegin(),
3058 diag::err_template_arg_reference_var)
3059 << Var->getType() << Arg->getSourceRange();
3060 S.Diag(Param->getLocation(), diag::note_template_param_here);
3064 // Okay: we've named an object with external linkage
3067 // If the template parameter has pointer type, we must have taken
3068 // the address of this object.
3069 if (ParamType->isReferenceType()) {
3071 // If we originally had an address-of operator, but the
3072 // parameter has reference type, complain and (if things look
3073 // like they will work) drop the address-of operator.
3074 if (!S.Context.hasSameUnqualifiedType(Var->getType(),
3075 ParamType.getNonReferenceType())) {
3076 S.Diag(AddrOpLoc, diag::err_template_arg_address_of_non_pointer)
3078 S.Diag(Param->getLocation(), diag::note_template_param_here);
3082 S.Diag(AddrOpLoc, diag::err_template_arg_address_of_non_pointer)
3084 << FixItHint::CreateRemoval(AddrOpLoc);
3085 S.Diag(Param->getLocation(), diag::note_template_param_here);
3087 ArgType = Var->getType();
3089 } else if (!AddressTaken && ParamType->isPointerType()) {
3090 if (Var->getType()->isArrayType()) {
3091 // Array-to-pointer decay.
3092 ArgType = S.Context.getArrayDecayedType(Var->getType());
3094 // If the template parameter has pointer type but the address of
3095 // this object was not taken, complain and (possibly) recover by
3096 // taking the address of the entity.
3097 ArgType = S.Context.getPointerType(Var->getType());
3098 if (!S.Context.hasSameUnqualifiedType(ArgType, ParamType)) {
3099 S.Diag(Arg->getLocStart(), diag::err_template_arg_not_address_of)
3101 S.Diag(Param->getLocation(), diag::note_template_param_here);
3105 S.Diag(Arg->getLocStart(), diag::err_template_arg_not_address_of)
3107 << FixItHint::CreateInsertion(Arg->getLocStart(), "&");
3109 S.Diag(Param->getLocation(), diag::note_template_param_here);
3113 // We found something else, but we don't know specifically what it is.
3114 S.Diag(Arg->getSourceRange().getBegin(),
3115 diag::err_template_arg_not_object_or_func)
3116 << Arg->getSourceRange();
3117 S.Diag(DRE->getDecl()->getLocation(), diag::note_template_arg_refers_here);
3121 if (ParamType->isPointerType() &&
3122 !ParamType->getAs<PointerType>()->getPointeeType()->isFunctionType() &&
3123 S.IsQualificationConversion(ArgType, ParamType, false)) {
3124 // For pointer-to-object types, qualification conversions are
3127 if (const ReferenceType *ParamRef = ParamType->getAs<ReferenceType>()) {
3128 if (!ParamRef->getPointeeType()->isFunctionType()) {
3129 // C++ [temp.arg.nontype]p5b3:
3130 // For a non-type template-parameter of type reference to
3131 // object, no conversions apply. The type referred to by the
3132 // reference may be more cv-qualified than the (otherwise
3133 // identical) type of the template- argument. The
3134 // template-parameter is bound directly to the
3135 // template-argument, which shall be an lvalue.
3137 // FIXME: Other qualifiers?
3138 unsigned ParamQuals = ParamRef->getPointeeType().getCVRQualifiers();
3139 unsigned ArgQuals = ArgType.getCVRQualifiers();
3141 if ((ParamQuals | ArgQuals) != ParamQuals) {
3142 S.Diag(Arg->getSourceRange().getBegin(),
3143 diag::err_template_arg_ref_bind_ignores_quals)
3144 << ParamType << Arg->getType()
3145 << Arg->getSourceRange();
3146 S.Diag(Param->getLocation(), diag::note_template_param_here);
3152 // At this point, the template argument refers to an object or
3153 // function with external linkage. We now need to check whether the
3154 // argument and parameter types are compatible.
3155 if (!S.Context.hasSameUnqualifiedType(ArgType,
3156 ParamType.getNonReferenceType())) {
3157 // We can't perform this conversion or binding.
3158 if (ParamType->isReferenceType())
3159 S.Diag(Arg->getLocStart(), diag::err_template_arg_no_ref_bind)
3160 << ParamType << Arg->getType() << Arg->getSourceRange();
3162 S.Diag(Arg->getLocStart(), diag::err_template_arg_not_convertible)
3163 << Arg->getType() << ParamType << Arg->getSourceRange();
3164 S.Diag(Param->getLocation(), diag::note_template_param_here);
3169 // Create the template argument.
3170 Converted = TemplateArgument(Entity->getCanonicalDecl());
3171 S.MarkDeclarationReferenced(Arg->getLocStart(), Entity);
3175 /// \brief Checks whether the given template argument is a pointer to
3176 /// member constant according to C++ [temp.arg.nontype]p1.
3177 bool Sema::CheckTemplateArgumentPointerToMember(Expr *Arg,
3178 TemplateArgument &Converted) {
3179 bool Invalid = false;
3181 // See through any implicit casts we added to fix the type.
3182 while (ImplicitCastExpr *Cast = dyn_cast<ImplicitCastExpr>(Arg))
3183 Arg = Cast->getSubExpr();
3185 // C++ [temp.arg.nontype]p1:
3187 // A template-argument for a non-type, non-template
3188 // template-parameter shall be one of: [...]
3190 // -- a pointer to member expressed as described in 5.3.1.
3191 DeclRefExpr *DRE = 0;
3193 // In C++98/03 mode, give an extension warning on any extra parentheses.
3194 // See http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_defects.html#773
3195 bool ExtraParens = false;
3196 while (ParenExpr *Parens = dyn_cast<ParenExpr>(Arg)) {
3197 if (!Invalid && !ExtraParens && !getLangOptions().CPlusPlus0x) {
3198 Diag(Arg->getSourceRange().getBegin(),
3199 diag::ext_template_arg_extra_parens)
3200 << Arg->getSourceRange();
3204 Arg = Parens->getSubExpr();
3207 // A pointer-to-member constant written &Class::member.
3208 if (UnaryOperator *UnOp = dyn_cast<UnaryOperator>(Arg)) {
3209 if (UnOp->getOpcode() == UO_AddrOf) {
3210 DRE = dyn_cast<DeclRefExpr>(UnOp->getSubExpr());
3211 if (DRE && !DRE->getQualifier())
3215 // A constant of pointer-to-member type.
3216 else if ((DRE = dyn_cast<DeclRefExpr>(Arg))) {
3217 if (ValueDecl *VD = dyn_cast<ValueDecl>(DRE->getDecl())) {
3218 if (VD->getType()->isMemberPointerType()) {
3219 if (isa<NonTypeTemplateParmDecl>(VD) ||
3220 (isa<VarDecl>(VD) &&
3221 Context.getCanonicalType(VD->getType()).isConstQualified())) {
3222 if (Arg->isTypeDependent() || Arg->isValueDependent())
3223 Converted = TemplateArgument(Arg);
3225 Converted = TemplateArgument(VD->getCanonicalDecl());
3235 return Diag(Arg->getSourceRange().getBegin(),
3236 diag::err_template_arg_not_pointer_to_member_form)
3237 << Arg->getSourceRange();
3239 if (isa<FieldDecl>(DRE->getDecl()) || isa<CXXMethodDecl>(DRE->getDecl())) {
3240 assert((isa<FieldDecl>(DRE->getDecl()) ||
3241 !cast<CXXMethodDecl>(DRE->getDecl())->isStatic()) &&
3242 "Only non-static member pointers can make it here");
3244 // Okay: this is the address of a non-static member, and therefore
3245 // a member pointer constant.
3246 if (Arg->isTypeDependent() || Arg->isValueDependent())
3247 Converted = TemplateArgument(Arg);
3249 Converted = TemplateArgument(DRE->getDecl()->getCanonicalDecl());
3253 // We found something else, but we don't know specifically what it is.
3254 Diag(Arg->getSourceRange().getBegin(),
3255 diag::err_template_arg_not_pointer_to_member_form)
3256 << Arg->getSourceRange();
3257 Diag(DRE->getDecl()->getLocation(),
3258 diag::note_template_arg_refers_here);
3262 /// \brief Check a template argument against its corresponding
3263 /// non-type template parameter.
3265 /// This routine implements the semantics of C++ [temp.arg.nontype].
3266 /// It returns true if an error occurred, and false otherwise. \p
3267 /// InstantiatedParamType is the type of the non-type template
3268 /// parameter after it has been instantiated.
3270 /// If no error was detected, Converted receives the converted template argument.
3271 bool Sema::CheckTemplateArgument(NonTypeTemplateParmDecl *Param,
3272 QualType InstantiatedParamType, Expr *&Arg,
3273 TemplateArgument &Converted,
3274 CheckTemplateArgumentKind CTAK) {
3275 SourceLocation StartLoc = Arg->getSourceRange().getBegin();
3277 // If either the parameter has a dependent type or the argument is
3278 // type-dependent, there's nothing we can check now.
3279 if (InstantiatedParamType->isDependentType() || Arg->isTypeDependent()) {
3280 // FIXME: Produce a cloned, canonical expression?
3281 Converted = TemplateArgument(Arg);
3285 // C++ [temp.arg.nontype]p5:
3286 // The following conversions are performed on each expression used
3287 // as a non-type template-argument. If a non-type
3288 // template-argument cannot be converted to the type of the
3289 // corresponding template-parameter then the program is
3292 // -- for a non-type template-parameter of integral or
3293 // enumeration type, integral promotions (4.5) and integral
3294 // conversions (4.7) are applied.
3295 QualType ParamType = InstantiatedParamType;
3296 QualType ArgType = Arg->getType();
3297 if (ParamType->isIntegralOrEnumerationType()) {
3298 // C++ [temp.arg.nontype]p1:
3299 // A template-argument for a non-type, non-template
3300 // template-parameter shall be one of:
3302 // -- an integral constant-expression of integral or enumeration
3304 // -- the name of a non-type template-parameter; or
3305 SourceLocation NonConstantLoc;
3307 if (!ArgType->isIntegralOrEnumerationType()) {
3308 Diag(Arg->getSourceRange().getBegin(),
3309 diag::err_template_arg_not_integral_or_enumeral)
3310 << ArgType << Arg->getSourceRange();
3311 Diag(Param->getLocation(), diag::note_template_param_here);
3313 } else if (!Arg->isValueDependent() &&
3314 !Arg->isIntegerConstantExpr(Value, Context, &NonConstantLoc)) {
3315 Diag(NonConstantLoc, diag::err_template_arg_not_ice)
3316 << ArgType << Arg->getSourceRange();
3320 // From here on out, all we care about are the unqualified forms
3321 // of the parameter and argument types.
3322 ParamType = ParamType.getUnqualifiedType();
3323 ArgType = ArgType.getUnqualifiedType();
3325 // Try to convert the argument to the parameter's type.
3326 if (Context.hasSameType(ParamType, ArgType)) {
3327 // Okay: no conversion necessary
3328 } else if (CTAK == CTAK_Deduced) {
3329 // C++ [temp.deduct.type]p17:
3330 // If, in the declaration of a function template with a non-type
3331 // template-parameter, the non-type template- parameter is used
3332 // in an expression in the function parameter-list and, if the
3333 // corresponding template-argument is deduced, the
3334 // template-argument type shall match the type of the
3335 // template-parameter exactly, except that a template-argument
3336 // deduced from an array bound may be of any integral type.
3337 Diag(StartLoc, diag::err_deduced_non_type_template_arg_type_mismatch)
3338 << ArgType << ParamType;
3339 Diag(Param->getLocation(), diag::note_template_param_here);
3341 } else if (ParamType->isBooleanType()) {
3342 // This is an integral-to-boolean conversion.
3343 ImpCastExprToType(Arg, ParamType, CK_IntegralToBoolean);
3344 } else if (IsIntegralPromotion(Arg, ArgType, ParamType) ||
3345 !ParamType->isEnumeralType()) {
3346 // This is an integral promotion or conversion.
3347 ImpCastExprToType(Arg, ParamType, CK_IntegralCast);
3349 // We can't perform this conversion.
3350 Diag(Arg->getSourceRange().getBegin(),
3351 diag::err_template_arg_not_convertible)
3352 << Arg->getType() << InstantiatedParamType << Arg->getSourceRange();
3353 Diag(Param->getLocation(), diag::note_template_param_here);
3357 QualType IntegerType = Context.getCanonicalType(ParamType);
3358 if (const EnumType *Enum = IntegerType->getAs<EnumType>())
3359 IntegerType = Context.getCanonicalType(Enum->getDecl()->getIntegerType());
3361 if (!Arg->isValueDependent()) {
3362 llvm::APSInt OldValue = Value;
3364 // Coerce the template argument's value to the value it will have
3365 // based on the template parameter's type.
3366 unsigned AllowedBits = Context.getTypeSize(IntegerType);
3367 if (Value.getBitWidth() != AllowedBits)
3368 Value = Value.extOrTrunc(AllowedBits);
3369 Value.setIsSigned(IntegerType->isSignedIntegerType());
3371 // Complain if an unsigned parameter received a negative value.
3372 if (IntegerType->isUnsignedIntegerType()
3373 && (OldValue.isSigned() && OldValue.isNegative())) {
3374 Diag(Arg->getSourceRange().getBegin(), diag::warn_template_arg_negative)
3375 << OldValue.toString(10) << Value.toString(10) << Param->getType()
3376 << Arg->getSourceRange();
3377 Diag(Param->getLocation(), diag::note_template_param_here);
3380 // Complain if we overflowed the template parameter's type.
3381 unsigned RequiredBits;
3382 if (IntegerType->isUnsignedIntegerType())
3383 RequiredBits = OldValue.getActiveBits();
3384 else if (OldValue.isUnsigned())
3385 RequiredBits = OldValue.getActiveBits() + 1;
3387 RequiredBits = OldValue.getMinSignedBits();
3388 if (RequiredBits > AllowedBits) {
3389 Diag(Arg->getSourceRange().getBegin(),
3390 diag::warn_template_arg_too_large)
3391 << OldValue.toString(10) << Value.toString(10) << Param->getType()
3392 << Arg->getSourceRange();
3393 Diag(Param->getLocation(), diag::note_template_param_here);
3397 // Add the value of this argument to the list of converted
3398 // arguments. We use the bitwidth and signedness of the template
3400 if (Arg->isValueDependent()) {
3401 // The argument is value-dependent. Create a new
3402 // TemplateArgument with the converted expression.
3403 Converted = TemplateArgument(Arg);
3407 Converted = TemplateArgument(Value,
3408 ParamType->isEnumeralType() ? ParamType
3413 DeclAccessPair FoundResult; // temporary for ResolveOverloadedFunction
3415 // C++0x [temp.arg.nontype]p5 bullets 2, 4 and 6 permit conversion
3416 // from a template argument of type std::nullptr_t to a non-type
3417 // template parameter of type pointer to object, pointer to
3418 // function, or pointer-to-member, respectively.
3419 if (ArgType->isNullPtrType() &&
3420 (ParamType->isPointerType() || ParamType->isMemberPointerType())) {
3421 Converted = TemplateArgument((NamedDecl *)0);
3425 // Handle pointer-to-function, reference-to-function, and
3426 // pointer-to-member-function all in (roughly) the same way.
3427 if (// -- For a non-type template-parameter of type pointer to
3428 // function, only the function-to-pointer conversion (4.3) is
3429 // applied. If the template-argument represents a set of
3430 // overloaded functions (or a pointer to such), the matching
3431 // function is selected from the set (13.4).
3432 (ParamType->isPointerType() &&
3433 ParamType->getAs<PointerType>()->getPointeeType()->isFunctionType()) ||
3434 // -- For a non-type template-parameter of type reference to
3435 // function, no conversions apply. If the template-argument
3436 // represents a set of overloaded functions, the matching
3437 // function is selected from the set (13.4).
3438 (ParamType->isReferenceType() &&
3439 ParamType->getAs<ReferenceType>()->getPointeeType()->isFunctionType()) ||
3440 // -- For a non-type template-parameter of type pointer to
3441 // member function, no conversions apply. If the
3442 // template-argument represents a set of overloaded member
3443 // functions, the matching member function is selected from
3445 (ParamType->isMemberPointerType() &&
3446 ParamType->getAs<MemberPointerType>()->getPointeeType()
3447 ->isFunctionType())) {
3449 if (Arg->getType() == Context.OverloadTy) {
3450 if (FunctionDecl *Fn = ResolveAddressOfOverloadedFunction(Arg, ParamType,
3453 if (DiagnoseUseOfDecl(Fn, Arg->getSourceRange().getBegin()))
3456 Arg = FixOverloadedFunctionReference(Arg, FoundResult, Fn);
3457 ArgType = Arg->getType();
3462 if (!ParamType->isMemberPointerType())
3463 return CheckTemplateArgumentAddressOfObjectOrFunction(*this, Param,
3467 if (IsQualificationConversion(ArgType, ParamType.getNonReferenceType(),
3469 ImpCastExprToType(Arg, ParamType, CK_NoOp, CastCategory(Arg));
3470 } else if (!Context.hasSameUnqualifiedType(ArgType,
3471 ParamType.getNonReferenceType())) {
3472 // We can't perform this conversion.
3473 Diag(Arg->getSourceRange().getBegin(),
3474 diag::err_template_arg_not_convertible)
3475 << Arg->getType() << InstantiatedParamType << Arg->getSourceRange();
3476 Diag(Param->getLocation(), diag::note_template_param_here);
3480 return CheckTemplateArgumentPointerToMember(Arg, Converted);
3483 if (ParamType->isPointerType()) {
3484 // -- for a non-type template-parameter of type pointer to
3485 // object, qualification conversions (4.4) and the
3486 // array-to-pointer conversion (4.2) are applied.
3487 // C++0x also allows a value of std::nullptr_t.
3488 assert(ParamType->getPointeeType()->isIncompleteOrObjectType() &&
3489 "Only object pointers allowed here");
3491 return CheckTemplateArgumentAddressOfObjectOrFunction(*this, Param,
3496 if (const ReferenceType *ParamRefType = ParamType->getAs<ReferenceType>()) {
3497 // -- For a non-type template-parameter of type reference to
3498 // object, no conversions apply. The type referred to by the
3499 // reference may be more cv-qualified than the (otherwise
3500 // identical) type of the template-argument. The
3501 // template-parameter is bound directly to the
3502 // template-argument, which must be an lvalue.
3503 assert(ParamRefType->getPointeeType()->isIncompleteOrObjectType() &&
3504 "Only object references allowed here");
3506 if (Arg->getType() == Context.OverloadTy) {
3507 if (FunctionDecl *Fn = ResolveAddressOfOverloadedFunction(Arg,
3508 ParamRefType->getPointeeType(),
3511 if (DiagnoseUseOfDecl(Fn, Arg->getSourceRange().getBegin()))
3514 Arg = FixOverloadedFunctionReference(Arg, FoundResult, Fn);
3515 ArgType = Arg->getType();
3520 return CheckTemplateArgumentAddressOfObjectOrFunction(*this, Param,
3525 // -- For a non-type template-parameter of type pointer to data
3526 // member, qualification conversions (4.4) are applied.
3527 assert(ParamType->isMemberPointerType() && "Only pointers to members remain");
3529 if (Context.hasSameUnqualifiedType(ParamType, ArgType)) {
3530 // Types match exactly: nothing more to do here.
3531 } else if (IsQualificationConversion(ArgType, ParamType, false)) {
3532 ImpCastExprToType(Arg, ParamType, CK_NoOp, CastCategory(Arg));
3534 // We can't perform this conversion.
3535 Diag(Arg->getSourceRange().getBegin(),
3536 diag::err_template_arg_not_convertible)
3537 << Arg->getType() << InstantiatedParamType << Arg->getSourceRange();
3538 Diag(Param->getLocation(), diag::note_template_param_here);
3542 return CheckTemplateArgumentPointerToMember(Arg, Converted);
3545 /// \brief Check a template argument against its corresponding
3546 /// template template parameter.
3548 /// This routine implements the semantics of C++ [temp.arg.template].
3549 /// It returns true if an error occurred, and false otherwise.
3550 bool Sema::CheckTemplateArgument(TemplateTemplateParmDecl *Param,
3551 const TemplateArgumentLoc &Arg) {
3552 TemplateName Name = Arg.getArgument().getAsTemplate();
3553 TemplateDecl *Template = Name.getAsTemplateDecl();
3555 // Any dependent template name is fine.
3556 assert(Name.isDependent() && "Non-dependent template isn't a declaration?");
3560 // C++ [temp.arg.template]p1:
3561 // A template-argument for a template template-parameter shall be
3562 // the name of a class template, expressed as id-expression. Only
3563 // primary class templates are considered when matching the
3564 // template template argument with the corresponding parameter;
3565 // partial specializations are not considered even if their
3566 // parameter lists match that of the template template parameter.
3568 // Note that we also allow template template parameters here, which
3569 // will happen when we are dealing with, e.g., class template
3570 // partial specializations.
3571 if (!isa<ClassTemplateDecl>(Template) &&
3572 !isa<TemplateTemplateParmDecl>(Template)) {
3573 assert(isa<FunctionTemplateDecl>(Template) &&
3574 "Only function templates are possible here");
3575 Diag(Arg.getLocation(), diag::err_template_arg_not_class_template);
3576 Diag(Template->getLocation(), diag::note_template_arg_refers_here_func)
3580 return !TemplateParameterListsAreEqual(Template->getTemplateParameters(),
3581 Param->getTemplateParameters(),
3583 TPL_TemplateTemplateArgumentMatch,
3587 /// \brief Given a non-type template argument that refers to a
3588 /// declaration and the type of its corresponding non-type template
3589 /// parameter, produce an expression that properly refers to that
3592 Sema::BuildExpressionFromDeclTemplateArgument(const TemplateArgument &Arg,
3594 SourceLocation Loc) {
3595 assert(Arg.getKind() == TemplateArgument::Declaration &&
3596 "Only declaration template arguments permitted here");
3597 ValueDecl *VD = cast<ValueDecl>(Arg.getAsDecl());
3599 if (VD->getDeclContext()->isRecord() &&
3600 (isa<CXXMethodDecl>(VD) || isa<FieldDecl>(VD))) {
3601 // If the value is a class member, we might have a pointer-to-member.
3602 // Determine whether the non-type template template parameter is of
3603 // pointer-to-member type. If so, we need to build an appropriate
3604 // expression for a pointer-to-member, since a "normal" DeclRefExpr
3605 // would refer to the member itself.
3606 if (ParamType->isMemberPointerType()) {
3608 = Context.getTypeDeclType(cast<RecordDecl>(VD->getDeclContext()));
3609 NestedNameSpecifier *Qualifier
3610 = NestedNameSpecifier::Create(Context, 0, false,
3611 ClassType.getTypePtr());
3613 SS.setScopeRep(Qualifier);
3615 // The actual value-ness of this is unimportant, but for
3616 // internal consistency's sake, references to instance methods
3618 ExprValueKind VK = VK_LValue;
3619 if (isa<CXXMethodDecl>(VD) && cast<CXXMethodDecl>(VD)->isInstance())
3622 ExprResult RefExpr = BuildDeclRefExpr(VD,
3623 VD->getType().getNonReferenceType(),
3627 if (RefExpr.isInvalid())
3630 RefExpr = CreateBuiltinUnaryOp(Loc, UO_AddrOf, RefExpr.get());
3632 // We might need to perform a trailing qualification conversion, since
3633 // the element type on the parameter could be more qualified than the
3634 // element type in the expression we constructed.
3635 if (IsQualificationConversion(((Expr*) RefExpr.get())->getType(),
3636 ParamType.getUnqualifiedType(), false)) {
3637 Expr *RefE = RefExpr.takeAs<Expr>();
3638 ImpCastExprToType(RefE, ParamType.getUnqualifiedType(), CK_NoOp);
3639 RefExpr = Owned(RefE);
3642 assert(!RefExpr.isInvalid() &&
3643 Context.hasSameType(((Expr*) RefExpr.get())->getType(),
3644 ParamType.getUnqualifiedType()));
3645 return move(RefExpr);
3649 QualType T = VD->getType().getNonReferenceType();
3650 if (ParamType->isPointerType()) {
3651 // When the non-type template parameter is a pointer, take the
3652 // address of the declaration.
3653 ExprResult RefExpr = BuildDeclRefExpr(VD, T, VK_LValue, Loc);
3654 if (RefExpr.isInvalid())
3657 if (T->isFunctionType() || T->isArrayType()) {
3658 // Decay functions and arrays.
3659 Expr *RefE = (Expr *)RefExpr.get();
3660 DefaultFunctionArrayConversion(RefE);
3661 if (RefE != RefExpr.get()) {
3663 RefExpr = Owned(RefE);
3666 return move(RefExpr);
3669 // Take the address of everything else
3670 return CreateBuiltinUnaryOp(Loc, UO_AddrOf, RefExpr.get());
3673 ExprValueKind VK = VK_RValue;
3675 // If the non-type template parameter has reference type, qualify the
3676 // resulting declaration reference with the extra qualifiers on the
3677 // type that the reference refers to.
3678 if (const ReferenceType *TargetRef = ParamType->getAs<ReferenceType>()) {
3680 T = Context.getQualifiedType(T,
3681 TargetRef->getPointeeType().getQualifiers());
3684 return BuildDeclRefExpr(VD, T, VK, Loc);
3687 /// \brief Construct a new expression that refers to the given
3688 /// integral template argument with the given source-location
3691 /// This routine takes care of the mapping from an integral template
3692 /// argument (which may have any integral type) to the appropriate
3695 Sema::BuildExpressionFromIntegralTemplateArgument(const TemplateArgument &Arg,
3696 SourceLocation Loc) {
3697 assert(Arg.getKind() == TemplateArgument::Integral &&
3698 "Operation is only valid for integral template arguments");
3699 QualType T = Arg.getIntegralType();
3700 if (T->isCharType() || T->isWideCharType())
3701 return Owned(new (Context) CharacterLiteral(
3702 Arg.getAsIntegral()->getZExtValue(),
3703 T->isWideCharType(),
3706 if (T->isBooleanType())
3707 return Owned(new (Context) CXXBoolLiteralExpr(
3708 Arg.getAsIntegral()->getBoolValue(),
3713 if (const EnumType *ET = T->getAs<EnumType>())
3714 BT = ET->getDecl()->getPromotionType();
3718 Expr *E = IntegerLiteral::Create(Context, *Arg.getAsIntegral(), BT, Loc);
3719 if (T->isEnumeralType()) {
3720 // FIXME: This is a hack. We need a better way to handle substituted
3721 // non-type template parameters.
3722 E = CStyleCastExpr::Create(Context, T, VK_RValue, CK_IntegralCast,
3724 Context.getTrivialTypeSourceInfo(T, Loc),
3731 /// \brief Match two template parameters within template parameter lists.
3732 static bool MatchTemplateParameterKind(Sema &S, NamedDecl *New, NamedDecl *Old,
3734 Sema::TemplateParameterListEqualKind Kind,
3735 SourceLocation TemplateArgLoc) {
3736 // Check the actual kind (type, non-type, template).
3737 if (Old->getKind() != New->getKind()) {
3739 unsigned NextDiag = diag::err_template_param_different_kind;
3740 if (TemplateArgLoc.isValid()) {
3741 S.Diag(TemplateArgLoc, diag::err_template_arg_template_params_mismatch);
3742 NextDiag = diag::note_template_param_different_kind;
3744 S.Diag(New->getLocation(), NextDiag)
3745 << (Kind != Sema::TPL_TemplateMatch);
3746 S.Diag(Old->getLocation(), diag::note_template_prev_declaration)
3747 << (Kind != Sema::TPL_TemplateMatch);
3753 // Check that both are parameter packs are neither are parameter packs.
3754 // However, if we are matching a template template argument to a
3755 // template template parameter, the template template parameter can have
3756 // a parameter pack where the template template argument does not.
3757 if (Old->isTemplateParameterPack() != New->isTemplateParameterPack() &&
3758 !(Kind == Sema::TPL_TemplateTemplateArgumentMatch &&
3759 Old->isTemplateParameterPack())) {
3761 unsigned NextDiag = diag::err_template_parameter_pack_non_pack;
3762 if (TemplateArgLoc.isValid()) {
3763 S.Diag(TemplateArgLoc,
3764 diag::err_template_arg_template_params_mismatch);
3765 NextDiag = diag::note_template_parameter_pack_non_pack;
3768 unsigned ParamKind = isa<TemplateTypeParmDecl>(New)? 0
3769 : isa<NonTypeTemplateParmDecl>(New)? 1
3771 S.Diag(New->getLocation(), NextDiag)
3772 << ParamKind << New->isParameterPack();
3773 S.Diag(Old->getLocation(), diag::note_template_parameter_pack_here)
3774 << ParamKind << Old->isParameterPack();
3780 // For non-type template parameters, check the type of the parameter.
3781 if (NonTypeTemplateParmDecl *OldNTTP
3782 = dyn_cast<NonTypeTemplateParmDecl>(Old)) {
3783 NonTypeTemplateParmDecl *NewNTTP = cast<NonTypeTemplateParmDecl>(New);
3785 // If we are matching a template template argument to a template
3786 // template parameter and one of the non-type template parameter types
3787 // is dependent, then we must wait until template instantiation time
3788 // to actually compare the arguments.
3789 if (Kind == Sema::TPL_TemplateTemplateArgumentMatch &&
3790 (OldNTTP->getType()->isDependentType() ||
3791 NewNTTP->getType()->isDependentType()))
3794 if (!S.Context.hasSameType(OldNTTP->getType(), NewNTTP->getType())) {
3796 unsigned NextDiag = diag::err_template_nontype_parm_different_type;
3797 if (TemplateArgLoc.isValid()) {
3798 S.Diag(TemplateArgLoc,
3799 diag::err_template_arg_template_params_mismatch);
3800 NextDiag = diag::note_template_nontype_parm_different_type;
3802 S.Diag(NewNTTP->getLocation(), NextDiag)
3803 << NewNTTP->getType()
3804 << (Kind != Sema::TPL_TemplateMatch);
3805 S.Diag(OldNTTP->getLocation(),
3806 diag::note_template_nontype_parm_prev_declaration)
3807 << OldNTTP->getType();
3816 // For template template parameters, check the template parameter types.
3817 // The template parameter lists of template template
3818 // parameters must agree.
3819 if (TemplateTemplateParmDecl *OldTTP
3820 = dyn_cast<TemplateTemplateParmDecl>(Old)) {
3821 TemplateTemplateParmDecl *NewTTP = cast<TemplateTemplateParmDecl>(New);
3822 return S.TemplateParameterListsAreEqual(NewTTP->getTemplateParameters(),
3823 OldTTP->getTemplateParameters(),
3825 (Kind == Sema::TPL_TemplateMatch
3826 ? Sema::TPL_TemplateTemplateParmMatch
3834 /// \brief Diagnose a known arity mismatch when comparing template argument
3837 void DiagnoseTemplateParameterListArityMismatch(Sema &S,
3838 TemplateParameterList *New,
3839 TemplateParameterList *Old,
3840 Sema::TemplateParameterListEqualKind Kind,
3841 SourceLocation TemplateArgLoc) {
3842 unsigned NextDiag = diag::err_template_param_list_different_arity;
3843 if (TemplateArgLoc.isValid()) {
3844 S.Diag(TemplateArgLoc, diag::err_template_arg_template_params_mismatch);
3845 NextDiag = diag::note_template_param_list_different_arity;
3847 S.Diag(New->getTemplateLoc(), NextDiag)
3848 << (New->size() > Old->size())
3849 << (Kind != Sema::TPL_TemplateMatch)
3850 << SourceRange(New->getTemplateLoc(), New->getRAngleLoc());
3851 S.Diag(Old->getTemplateLoc(), diag::note_template_prev_declaration)
3852 << (Kind != Sema::TPL_TemplateMatch)
3853 << SourceRange(Old->getTemplateLoc(), Old->getRAngleLoc());
3856 /// \brief Determine whether the given template parameter lists are
3859 /// \param New The new template parameter list, typically written in the
3860 /// source code as part of a new template declaration.
3862 /// \param Old The old template parameter list, typically found via
3863 /// name lookup of the template declared with this template parameter
3866 /// \param Complain If true, this routine will produce a diagnostic if
3867 /// the template parameter lists are not equivalent.
3869 /// \param Kind describes how we are to match the template parameter lists.
3871 /// \param TemplateArgLoc If this source location is valid, then we
3872 /// are actually checking the template parameter list of a template
3873 /// argument (New) against the template parameter list of its
3874 /// corresponding template template parameter (Old). We produce
3875 /// slightly different diagnostics in this scenario.
3877 /// \returns True if the template parameter lists are equal, false
3880 Sema::TemplateParameterListsAreEqual(TemplateParameterList *New,
3881 TemplateParameterList *Old,
3883 TemplateParameterListEqualKind Kind,
3884 SourceLocation TemplateArgLoc) {
3885 if (Old->size() != New->size() && Kind != TPL_TemplateTemplateArgumentMatch) {
3887 DiagnoseTemplateParameterListArityMismatch(*this, New, Old, Kind,
3893 // C++0x [temp.arg.template]p3:
3894 // A template-argument matches a template template-parameter (call it P)
3895 // when each of the template parameters in the template-parameter-list of
3896 // the template-argument's corresponding class template or template alias
3897 // (call it A) matches the corresponding template parameter in the
3898 // template-parameter-list of P. [...]
3899 TemplateParameterList::iterator NewParm = New->begin();
3900 TemplateParameterList::iterator NewParmEnd = New->end();
3901 for (TemplateParameterList::iterator OldParm = Old->begin(),
3902 OldParmEnd = Old->end();
3903 OldParm != OldParmEnd; ++OldParm) {
3904 if (Kind != TPL_TemplateTemplateArgumentMatch ||
3905 !(*OldParm)->isTemplateParameterPack()) {
3906 if (NewParm == NewParmEnd) {
3908 DiagnoseTemplateParameterListArityMismatch(*this, New, Old, Kind,
3914 if (!MatchTemplateParameterKind(*this, *NewParm, *OldParm, Complain,
3915 Kind, TemplateArgLoc))
3922 // C++0x [temp.arg.template]p3:
3923 // [...] When P's template- parameter-list contains a template parameter
3924 // pack (14.5.3), the template parameter pack will match zero or more
3925 // template parameters or template parameter packs in the
3926 // template-parameter-list of A with the same type and form as the
3927 // template parameter pack in P (ignoring whether those template
3928 // parameters are template parameter packs).
3929 for (; NewParm != NewParmEnd; ++NewParm) {
3930 if (!MatchTemplateParameterKind(*this, *NewParm, *OldParm, Complain,
3931 Kind, TemplateArgLoc))
3936 // Make sure we exhausted all of the arguments.
3937 if (NewParm != NewParmEnd) {
3939 DiagnoseTemplateParameterListArityMismatch(*this, New, Old, Kind,
3948 /// \brief Check whether a template can be declared within this scope.
3950 /// If the template declaration is valid in this scope, returns
3951 /// false. Otherwise, issues a diagnostic and returns true.
3953 Sema::CheckTemplateDeclScope(Scope *S, TemplateParameterList *TemplateParams) {
3954 // Find the nearest enclosing declaration scope.
3955 while ((S->getFlags() & Scope::DeclScope) == 0 ||
3956 (S->getFlags() & Scope::TemplateParamScope) != 0)
3960 // A template-declaration can appear only as a namespace scope or
3961 // class scope declaration.
3962 DeclContext *Ctx = static_cast<DeclContext *>(S->getEntity());
3963 if (Ctx && isa<LinkageSpecDecl>(Ctx) &&
3964 cast<LinkageSpecDecl>(Ctx)->getLanguage() != LinkageSpecDecl::lang_cxx)
3965 return Diag(TemplateParams->getTemplateLoc(), diag::err_template_linkage)
3966 << TemplateParams->getSourceRange();
3968 while (Ctx && isa<LinkageSpecDecl>(Ctx))
3969 Ctx = Ctx->getParent();
3971 if (Ctx && (Ctx->isFileContext() || Ctx->isRecord()))
3974 return Diag(TemplateParams->getTemplateLoc(),
3975 diag::err_template_outside_namespace_or_class_scope)
3976 << TemplateParams->getSourceRange();
3979 /// \brief Determine what kind of template specialization the given declaration
3981 static TemplateSpecializationKind getTemplateSpecializationKind(NamedDecl *D) {
3983 return TSK_Undeclared;
3985 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(D))
3986 return Record->getTemplateSpecializationKind();
3987 if (FunctionDecl *Function = dyn_cast<FunctionDecl>(D))
3988 return Function->getTemplateSpecializationKind();
3989 if (VarDecl *Var = dyn_cast<VarDecl>(D))
3990 return Var->getTemplateSpecializationKind();
3992 return TSK_Undeclared;
3995 /// \brief Check whether a specialization is well-formed in the current
3998 /// This routine determines whether a template specialization can be declared
3999 /// in the current context (C++ [temp.expl.spec]p2).
4001 /// \param S the semantic analysis object for which this check is being
4004 /// \param Specialized the entity being specialized or instantiated, which
4005 /// may be a kind of template (class template, function template, etc.) or
4006 /// a member of a class template (member function, static data member,
4009 /// \param PrevDecl the previous declaration of this entity, if any.
4011 /// \param Loc the location of the explicit specialization or instantiation of
4014 /// \param IsPartialSpecialization whether this is a partial specialization of
4015 /// a class template.
4017 /// \returns true if there was an error that we cannot recover from, false
4019 static bool CheckTemplateSpecializationScope(Sema &S,
4020 NamedDecl *Specialized,
4021 NamedDecl *PrevDecl,
4023 bool IsPartialSpecialization) {
4024 // Keep these "kind" numbers in sync with the %select statements in the
4025 // various diagnostics emitted by this routine.
4027 if (isa<ClassTemplateDecl>(Specialized))
4028 EntityKind = IsPartialSpecialization? 1 : 0;
4029 else if (isa<FunctionTemplateDecl>(Specialized))
4031 else if (isa<CXXMethodDecl>(Specialized))
4033 else if (isa<VarDecl>(Specialized))
4035 else if (isa<RecordDecl>(Specialized))
4038 S.Diag(Loc, diag::err_template_spec_unknown_kind);
4039 S.Diag(Specialized->getLocation(), diag::note_specialized_entity);
4043 // C++ [temp.expl.spec]p2:
4044 // An explicit specialization shall be declared in the namespace
4045 // of which the template is a member, or, for member templates, in
4046 // the namespace of which the enclosing class or enclosing class
4047 // template is a member. An explicit specialization of a member
4048 // function, member class or static data member of a class
4049 // template shall be declared in the namespace of which the class
4050 // template is a member. Such a declaration may also be a
4051 // definition. If the declaration is not a definition, the
4052 // specialization may be defined later in the name- space in which
4053 // the explicit specialization was declared, or in a namespace
4054 // that encloses the one in which the explicit specialization was
4056 if (S.CurContext->getRedeclContext()->isFunctionOrMethod()) {
4057 S.Diag(Loc, diag::err_template_spec_decl_function_scope)
4062 if (S.CurContext->isRecord() && !IsPartialSpecialization) {
4063 S.Diag(Loc, diag::err_template_spec_decl_class_scope)
4068 // C++ [temp.class.spec]p6:
4069 // A class template partial specialization may be declared or redeclared
4070 // in any namespace scope in which its definition may be defined (14.5.1
4072 bool ComplainedAboutScope = false;
4073 DeclContext *SpecializedContext
4074 = Specialized->getDeclContext()->getEnclosingNamespaceContext();
4075 DeclContext *DC = S.CurContext->getEnclosingNamespaceContext();
4077 getTemplateSpecializationKind(PrevDecl) == TSK_Undeclared ||
4078 getTemplateSpecializationKind(PrevDecl) == TSK_ImplicitInstantiation)){
4079 // C++ [temp.exp.spec]p2:
4080 // An explicit specialization shall be declared in the namespace of which
4081 // the template is a member, or, for member templates, in the namespace
4082 // of which the enclosing class or enclosing class template is a member.
4083 // An explicit specialization of a member function, member class or
4084 // static data member of a class template shall be declared in the
4085 // namespace of which the class template is a member.
4087 // C++0x [temp.expl.spec]p2:
4088 // An explicit specialization shall be declared in a namespace enclosing
4089 // the specialized template.
4090 if (!DC->InEnclosingNamespaceSetOf(SpecializedContext) &&
4091 !(S.getLangOptions().CPlusPlus0x && DC->Encloses(SpecializedContext))) {
4092 bool IsCPlusPlus0xExtension
4093 = !S.getLangOptions().CPlusPlus0x && DC->Encloses(SpecializedContext);
4094 if (isa<TranslationUnitDecl>(SpecializedContext))
4095 S.Diag(Loc, IsCPlusPlus0xExtension
4096 ? diag::ext_template_spec_decl_out_of_scope_global
4097 : diag::err_template_spec_decl_out_of_scope_global)
4098 << EntityKind << Specialized;
4099 else if (isa<NamespaceDecl>(SpecializedContext))
4100 S.Diag(Loc, IsCPlusPlus0xExtension
4101 ? diag::ext_template_spec_decl_out_of_scope
4102 : diag::err_template_spec_decl_out_of_scope)
4103 << EntityKind << Specialized
4104 << cast<NamedDecl>(SpecializedContext);
4106 S.Diag(Specialized->getLocation(), diag::note_specialized_entity);
4107 ComplainedAboutScope = true;
4111 // Make sure that this redeclaration (or definition) occurs in an enclosing
4113 // Note that HandleDeclarator() performs this check for explicit
4114 // specializations of function templates, static data members, and member
4115 // functions, so we skip the check here for those kinds of entities.
4116 // FIXME: HandleDeclarator's diagnostics aren't quite as good, though.
4117 // Should we refactor that check, so that it occurs later?
4118 if (!ComplainedAboutScope && !DC->Encloses(SpecializedContext) &&
4119 !(isa<FunctionTemplateDecl>(Specialized) || isa<VarDecl>(Specialized) ||
4120 isa<FunctionDecl>(Specialized))) {
4121 if (isa<TranslationUnitDecl>(SpecializedContext))
4122 S.Diag(Loc, diag::err_template_spec_redecl_global_scope)
4123 << EntityKind << Specialized;
4124 else if (isa<NamespaceDecl>(SpecializedContext))
4125 S.Diag(Loc, diag::err_template_spec_redecl_out_of_scope)
4126 << EntityKind << Specialized
4127 << cast<NamedDecl>(SpecializedContext);
4129 S.Diag(Specialized->getLocation(), diag::note_specialized_entity);
4132 // FIXME: check for specialization-after-instantiation errors and such.
4137 /// \brief Subroutine of Sema::CheckClassTemplatePartialSpecializationArgs
4138 /// that checks non-type template partial specialization arguments.
4139 static bool CheckNonTypeClassTemplatePartialSpecializationArgs(Sema &S,
4140 NonTypeTemplateParmDecl *Param,
4141 const TemplateArgument *Args,
4143 for (unsigned I = 0; I != NumArgs; ++I) {
4144 if (Args[I].getKind() == TemplateArgument::Pack) {
4145 if (CheckNonTypeClassTemplatePartialSpecializationArgs(S, Param,
4146 Args[I].pack_begin(),
4147 Args[I].pack_size()))
4153 Expr *ArgExpr = Args[I].getAsExpr();
4158 // We can have a pack expansion of any of the bullets below.
4159 if (PackExpansionExpr *Expansion = dyn_cast<PackExpansionExpr>(ArgExpr))
4160 ArgExpr = Expansion->getPattern();
4162 // Strip off any implicit casts we added as part of type checking.
4163 while (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(ArgExpr))
4164 ArgExpr = ICE->getSubExpr();
4166 // C++ [temp.class.spec]p8:
4167 // A non-type argument is non-specialized if it is the name of a
4168 // non-type parameter. All other non-type arguments are
4171 // Below, we check the two conditions that only apply to
4172 // specialized non-type arguments, so skip any non-specialized
4174 if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(ArgExpr))
4175 if (isa<NonTypeTemplateParmDecl>(DRE->getDecl()))
4178 // C++ [temp.class.spec]p9:
4179 // Within the argument list of a class template partial
4180 // specialization, the following restrictions apply:
4181 // -- A partially specialized non-type argument expression
4182 // shall not involve a template parameter of the partial
4183 // specialization except when the argument expression is a
4184 // simple identifier.
4185 if (ArgExpr->isTypeDependent() || ArgExpr->isValueDependent()) {
4186 S.Diag(ArgExpr->getLocStart(),
4187 diag::err_dependent_non_type_arg_in_partial_spec)
4188 << ArgExpr->getSourceRange();
4192 // -- The type of a template parameter corresponding to a
4193 // specialized non-type argument shall not be dependent on a
4194 // parameter of the specialization.
4195 if (Param->getType()->isDependentType()) {
4196 S.Diag(ArgExpr->getLocStart(),
4197 diag::err_dependent_typed_non_type_arg_in_partial_spec)
4199 << ArgExpr->getSourceRange();
4200 S.Diag(Param->getLocation(), diag::note_template_param_here);
4208 /// \brief Check the non-type template arguments of a class template
4209 /// partial specialization according to C++ [temp.class.spec]p9.
4211 /// \param TemplateParams the template parameters of the primary class
4214 /// \param TemplateArg the template arguments of the class template
4215 /// partial specialization.
4217 /// \returns true if there was an error, false otherwise.
4218 static bool CheckClassTemplatePartialSpecializationArgs(Sema &S,
4219 TemplateParameterList *TemplateParams,
4220 llvm::SmallVectorImpl<TemplateArgument> &TemplateArgs) {
4221 const TemplateArgument *ArgList = TemplateArgs.data();
4223 for (unsigned I = 0, N = TemplateParams->size(); I != N; ++I) {
4224 NonTypeTemplateParmDecl *Param
4225 = dyn_cast<NonTypeTemplateParmDecl>(TemplateParams->getParam(I));
4229 if (CheckNonTypeClassTemplatePartialSpecializationArgs(S, Param,
4237 /// \brief Retrieve the previous declaration of the given declaration.
4238 static NamedDecl *getPreviousDecl(NamedDecl *ND) {
4239 if (VarDecl *VD = dyn_cast<VarDecl>(ND))
4240 return VD->getPreviousDeclaration();
4241 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(ND))
4242 return FD->getPreviousDeclaration();
4243 if (TagDecl *TD = dyn_cast<TagDecl>(ND))
4244 return TD->getPreviousDeclaration();
4245 if (TypedefDecl *TD = dyn_cast<TypedefDecl>(ND))
4246 return TD->getPreviousDeclaration();
4247 if (FunctionTemplateDecl *FTD = dyn_cast<FunctionTemplateDecl>(ND))
4248 return FTD->getPreviousDeclaration();
4249 if (ClassTemplateDecl *CTD = dyn_cast<ClassTemplateDecl>(ND))
4250 return CTD->getPreviousDeclaration();
4255 Sema::ActOnClassTemplateSpecialization(Scope *S, unsigned TagSpec,
4257 SourceLocation KWLoc,
4259 TemplateTy TemplateD,
4260 SourceLocation TemplateNameLoc,
4261 SourceLocation LAngleLoc,
4262 ASTTemplateArgsPtr TemplateArgsIn,
4263 SourceLocation RAngleLoc,
4264 AttributeList *Attr,
4265 MultiTemplateParamsArg TemplateParameterLists) {
4266 assert(TUK != TUK_Reference && "References are not specializations");
4268 // Find the class template we're specializing
4269 TemplateName Name = TemplateD.getAsVal<TemplateName>();
4270 ClassTemplateDecl *ClassTemplate
4271 = dyn_cast_or_null<ClassTemplateDecl>(Name.getAsTemplateDecl());
4273 if (!ClassTemplate) {
4274 Diag(TemplateNameLoc, diag::err_not_class_template_specialization)
4275 << (Name.getAsTemplateDecl() &&
4276 isa<TemplateTemplateParmDecl>(Name.getAsTemplateDecl()));
4280 bool isExplicitSpecialization = false;
4281 bool isPartialSpecialization = false;
4283 // Check the validity of the template headers that introduce this
4285 // FIXME: We probably shouldn't complain about these headers for
4286 // friend declarations.
4287 bool Invalid = false;
4288 TemplateParameterList *TemplateParams
4289 = MatchTemplateParametersToScopeSpecifier(TemplateNameLoc, SS,
4290 (TemplateParameterList**)TemplateParameterLists.get(),
4291 TemplateParameterLists.size(),
4293 isExplicitSpecialization,
4298 unsigned NumMatchedTemplateParamLists = TemplateParameterLists.size();
4300 --NumMatchedTemplateParamLists;
4302 if (TemplateParams && TemplateParams->size() > 0) {
4303 isPartialSpecialization = true;
4305 if (TUK == TUK_Friend) {
4306 Diag(KWLoc, diag::err_partial_specialization_friend)
4307 << SourceRange(LAngleLoc, RAngleLoc);
4311 // C++ [temp.class.spec]p10:
4312 // The template parameter list of a specialization shall not
4313 // contain default template argument values.
4314 for (unsigned I = 0, N = TemplateParams->size(); I != N; ++I) {
4315 Decl *Param = TemplateParams->getParam(I);
4316 if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(Param)) {
4317 if (TTP->hasDefaultArgument()) {
4318 Diag(TTP->getDefaultArgumentLoc(),
4319 diag::err_default_arg_in_partial_spec);
4320 TTP->removeDefaultArgument();
4322 } else if (NonTypeTemplateParmDecl *NTTP
4323 = dyn_cast<NonTypeTemplateParmDecl>(Param)) {
4324 if (Expr *DefArg = NTTP->getDefaultArgument()) {
4325 Diag(NTTP->getDefaultArgumentLoc(),
4326 diag::err_default_arg_in_partial_spec)
4327 << DefArg->getSourceRange();
4328 NTTP->removeDefaultArgument();
4331 TemplateTemplateParmDecl *TTP = cast<TemplateTemplateParmDecl>(Param);
4332 if (TTP->hasDefaultArgument()) {
4333 Diag(TTP->getDefaultArgument().getLocation(),
4334 diag::err_default_arg_in_partial_spec)
4335 << TTP->getDefaultArgument().getSourceRange();
4336 TTP->removeDefaultArgument();
4340 } else if (TemplateParams) {
4341 if (TUK == TUK_Friend)
4342 Diag(KWLoc, diag::err_template_spec_friend)
4343 << FixItHint::CreateRemoval(
4344 SourceRange(TemplateParams->getTemplateLoc(),
4345 TemplateParams->getRAngleLoc()))
4346 << SourceRange(LAngleLoc, RAngleLoc);
4348 isExplicitSpecialization = true;
4349 } else if (TUK != TUK_Friend) {
4350 Diag(KWLoc, diag::err_template_spec_needs_header)
4351 << FixItHint::CreateInsertion(KWLoc, "template<> ");
4352 isExplicitSpecialization = true;
4355 // Check that the specialization uses the same tag kind as the
4356 // original template.
4357 TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec);
4358 assert(Kind != TTK_Enum && "Invalid enum tag in class template spec!");
4359 if (!isAcceptableTagRedeclaration(ClassTemplate->getTemplatedDecl(),
4361 *ClassTemplate->getIdentifier())) {
4362 Diag(KWLoc, diag::err_use_with_wrong_tag)
4364 << FixItHint::CreateReplacement(KWLoc,
4365 ClassTemplate->getTemplatedDecl()->getKindName());
4366 Diag(ClassTemplate->getTemplatedDecl()->getLocation(),
4367 diag::note_previous_use);
4368 Kind = ClassTemplate->getTemplatedDecl()->getTagKind();
4371 // Translate the parser's template argument list in our AST format.
4372 TemplateArgumentListInfo TemplateArgs;
4373 TemplateArgs.setLAngleLoc(LAngleLoc);
4374 TemplateArgs.setRAngleLoc(RAngleLoc);
4375 translateTemplateArguments(TemplateArgsIn, TemplateArgs);
4377 // Check for unexpanded parameter packs in any of the template arguments.
4378 for (unsigned I = 0, N = TemplateArgs.size(); I != N; ++I)
4379 if (DiagnoseUnexpandedParameterPack(TemplateArgs[I],
4380 UPPC_PartialSpecialization))
4383 // Check that the template argument list is well-formed for this
4385 llvm::SmallVector<TemplateArgument, 4> Converted;
4386 if (CheckTemplateArgumentList(ClassTemplate, TemplateNameLoc,
4387 TemplateArgs, false, Converted))
4390 assert((Converted.size() == ClassTemplate->getTemplateParameters()->size()) &&
4391 "Converted template argument list is too short!");
4393 // Find the class template (partial) specialization declaration that
4394 // corresponds to these arguments.
4395 if (isPartialSpecialization) {
4396 if (CheckClassTemplatePartialSpecializationArgs(*this,
4397 ClassTemplate->getTemplateParameters(),
4401 if (!Name.isDependent() &&
4402 !TemplateSpecializationType::anyDependentTemplateArguments(
4403 TemplateArgs.getArgumentArray(),
4404 TemplateArgs.size())) {
4405 Diag(TemplateNameLoc, diag::err_partial_spec_fully_specialized)
4406 << ClassTemplate->getDeclName();
4407 isPartialSpecialization = false;
4411 void *InsertPos = 0;
4412 ClassTemplateSpecializationDecl *PrevDecl = 0;
4414 if (isPartialSpecialization)
4415 // FIXME: Template parameter list matters, too
4417 = ClassTemplate->findPartialSpecialization(Converted.data(),
4422 = ClassTemplate->findSpecialization(Converted.data(),
4423 Converted.size(), InsertPos);
4425 ClassTemplateSpecializationDecl *Specialization = 0;
4427 // Check whether we can declare a class template specialization in
4428 // the current scope.
4429 if (TUK != TUK_Friend &&
4430 CheckTemplateSpecializationScope(*this, ClassTemplate, PrevDecl,
4432 isPartialSpecialization))
4435 // The canonical type
4438 (PrevDecl->getSpecializationKind() == TSK_Undeclared ||
4439 TUK == TUK_Friend)) {
4440 // Since the only prior class template specialization with these
4441 // arguments was referenced but not declared, or we're only
4442 // referencing this specialization as a friend, reuse that
4443 // declaration node as our own, updating its source location to
4444 // reflect our new declaration.
4445 Specialization = PrevDecl;
4446 Specialization->setLocation(TemplateNameLoc);
4448 CanonType = Context.getTypeDeclType(Specialization);
4449 } else if (isPartialSpecialization) {
4450 // Build the canonical type that describes the converted template
4451 // arguments of the class template partial specialization.
4452 TemplateName CanonTemplate = Context.getCanonicalTemplateName(Name);
4453 CanonType = Context.getTemplateSpecializationType(CanonTemplate,
4457 if (Context.hasSameType(CanonType,
4458 ClassTemplate->getInjectedClassNameSpecialization())) {
4459 // C++ [temp.class.spec]p9b3:
4461 // -- The argument list of the specialization shall not be identical
4462 // to the implicit argument list of the primary template.
4463 Diag(TemplateNameLoc, diag::err_partial_spec_args_match_primary_template)
4464 << (TUK == TUK_Definition)
4465 << FixItHint::CreateRemoval(SourceRange(LAngleLoc, RAngleLoc));
4466 return CheckClassTemplate(S, TagSpec, TUK, KWLoc, SS,
4467 ClassTemplate->getIdentifier(),
4474 // Create a new class template partial specialization declaration node.
4475 ClassTemplatePartialSpecializationDecl *PrevPartial
4476 = cast_or_null<ClassTemplatePartialSpecializationDecl>(PrevDecl);
4477 unsigned SequenceNumber = PrevPartial? PrevPartial->getSequenceNumber()
4478 : ClassTemplate->getNextPartialSpecSequenceNumber();
4479 ClassTemplatePartialSpecializationDecl *Partial
4480 = ClassTemplatePartialSpecializationDecl::Create(Context, Kind,
4481 ClassTemplate->getDeclContext(),
4491 SetNestedNameSpecifier(Partial, SS);
4492 if (NumMatchedTemplateParamLists > 0 && SS.isSet()) {
4493 Partial->setTemplateParameterListsInfo(Context,
4494 NumMatchedTemplateParamLists,
4495 (TemplateParameterList**) TemplateParameterLists.release());
4499 ClassTemplate->AddPartialSpecialization(Partial, InsertPos);
4500 Specialization = Partial;
4502 // If we are providing an explicit specialization of a member class
4503 // template specialization, make a note of that.
4504 if (PrevPartial && PrevPartial->getInstantiatedFromMember())
4505 PrevPartial->setMemberSpecialization();
4507 // Check that all of the template parameters of the class template
4508 // partial specialization are deducible from the template
4509 // arguments. If not, this class template partial specialization
4510 // will never be used.
4511 llvm::SmallVector<bool, 8> DeducibleParams;
4512 DeducibleParams.resize(TemplateParams->size());
4513 MarkUsedTemplateParameters(Partial->getTemplateArgs(), true,
4514 TemplateParams->getDepth(),
4516 unsigned NumNonDeducible = 0;
4517 for (unsigned I = 0, N = DeducibleParams.size(); I != N; ++I)
4518 if (!DeducibleParams[I])
4521 if (NumNonDeducible) {
4522 Diag(TemplateNameLoc, diag::warn_partial_specs_not_deducible)
4523 << (NumNonDeducible > 1)
4524 << SourceRange(TemplateNameLoc, RAngleLoc);
4525 for (unsigned I = 0, N = DeducibleParams.size(); I != N; ++I) {
4526 if (!DeducibleParams[I]) {
4527 NamedDecl *Param = cast<NamedDecl>(TemplateParams->getParam(I));
4528 if (Param->getDeclName())
4529 Diag(Param->getLocation(),
4530 diag::note_partial_spec_unused_parameter)
4531 << Param->getDeclName();
4533 Diag(Param->getLocation(),
4534 diag::note_partial_spec_unused_parameter)
4540 // Create a new class template specialization declaration node for
4541 // this explicit specialization or friend declaration.
4543 = ClassTemplateSpecializationDecl::Create(Context, Kind,
4544 ClassTemplate->getDeclContext(),
4550 SetNestedNameSpecifier(Specialization, SS);
4551 if (NumMatchedTemplateParamLists > 0 && SS.isSet()) {
4552 Specialization->setTemplateParameterListsInfo(Context,
4553 NumMatchedTemplateParamLists,
4554 (TemplateParameterList**) TemplateParameterLists.release());
4558 ClassTemplate->AddSpecialization(Specialization, InsertPos);
4560 CanonType = Context.getTypeDeclType(Specialization);
4563 // C++ [temp.expl.spec]p6:
4564 // If a template, a member template or the member of a class template is
4565 // explicitly specialized then that specialization shall be declared
4566 // before the first use of that specialization that would cause an implicit
4567 // instantiation to take place, in every translation unit in which such a
4568 // use occurs; no diagnostic is required.
4569 if (PrevDecl && PrevDecl->getPointOfInstantiation().isValid()) {
4571 for (NamedDecl *Prev = PrevDecl; Prev; Prev = getPreviousDecl(Prev)) {
4572 // Is there any previous explicit specialization declaration?
4573 if (getTemplateSpecializationKind(Prev) == TSK_ExplicitSpecialization) {
4580 SourceRange Range(TemplateNameLoc, RAngleLoc);
4581 Diag(TemplateNameLoc, diag::err_specialization_after_instantiation)
4582 << Context.getTypeDeclType(Specialization) << Range;
4584 Diag(PrevDecl->getPointOfInstantiation(),
4585 diag::note_instantiation_required_here)
4586 << (PrevDecl->getTemplateSpecializationKind()
4587 != TSK_ImplicitInstantiation);
4592 // If this is not a friend, note that this is an explicit specialization.
4593 if (TUK != TUK_Friend)
4594 Specialization->setSpecializationKind(TSK_ExplicitSpecialization);
4596 // Check that this isn't a redefinition of this specialization.
4597 if (TUK == TUK_Definition) {
4598 if (RecordDecl *Def = Specialization->getDefinition()) {
4599 SourceRange Range(TemplateNameLoc, RAngleLoc);
4600 Diag(TemplateNameLoc, diag::err_redefinition)
4601 << Context.getTypeDeclType(Specialization) << Range;
4602 Diag(Def->getLocation(), diag::note_previous_definition);
4603 Specialization->setInvalidDecl();
4609 ProcessDeclAttributeList(S, Specialization, Attr);
4611 // Build the fully-sugared type for this class template
4612 // specialization as the user wrote in the specialization
4613 // itself. This means that we'll pretty-print the type retrieved
4614 // from the specialization's declaration the way that the user
4615 // actually wrote the specialization, rather than formatting the
4616 // name based on the "canonical" representation used to store the
4617 // template arguments in the specialization.
4618 TypeSourceInfo *WrittenTy
4619 = Context.getTemplateSpecializationTypeInfo(Name, TemplateNameLoc,
4620 TemplateArgs, CanonType);
4621 if (TUK != TUK_Friend) {
4622 Specialization->setTypeAsWritten(WrittenTy);
4624 Specialization->setTemplateKeywordLoc(TemplateParams->getTemplateLoc());
4626 TemplateArgsIn.release();
4628 // C++ [temp.expl.spec]p9:
4629 // A template explicit specialization is in the scope of the
4630 // namespace in which the template was defined.
4632 // We actually implement this paragraph where we set the semantic
4633 // context (in the creation of the ClassTemplateSpecializationDecl),
4634 // but we also maintain the lexical context where the actual
4635 // definition occurs.
4636 Specialization->setLexicalDeclContext(CurContext);
4638 // We may be starting the definition of this specialization.
4639 if (TUK == TUK_Definition)
4640 Specialization->startDefinition();
4642 if (TUK == TUK_Friend) {
4643 FriendDecl *Friend = FriendDecl::Create(Context, CurContext,
4647 Friend->setAccess(AS_public);
4648 CurContext->addDecl(Friend);
4650 // Add the specialization into its lexical context, so that it can
4651 // be seen when iterating through the list of declarations in that
4652 // context. However, specializations are not found by name lookup.
4653 CurContext->addDecl(Specialization);
4655 return Specialization;
4658 Decl *Sema::ActOnTemplateDeclarator(Scope *S,
4659 MultiTemplateParamsArg TemplateParameterLists,
4661 return HandleDeclarator(S, D, move(TemplateParameterLists), false);
4664 Decl *Sema::ActOnStartOfFunctionTemplateDef(Scope *FnBodyScope,
4665 MultiTemplateParamsArg TemplateParameterLists,
4667 assert(getCurFunctionDecl() == 0 && "Function parsing confused");
4668 DeclaratorChunk::FunctionTypeInfo &FTI = D.getFunctionTypeInfo();
4670 if (FTI.hasPrototype) {
4671 // FIXME: Diagnose arguments without names in C.
4674 Scope *ParentScope = FnBodyScope->getParent();
4676 Decl *DP = HandleDeclarator(ParentScope, D,
4677 move(TemplateParameterLists),
4678 /*IsFunctionDefinition=*/true);
4679 if (FunctionTemplateDecl *FunctionTemplate
4680 = dyn_cast_or_null<FunctionTemplateDecl>(DP))
4681 return ActOnStartOfFunctionDef(FnBodyScope,
4682 FunctionTemplate->getTemplatedDecl());
4683 if (FunctionDecl *Function = dyn_cast_or_null<FunctionDecl>(DP))
4684 return ActOnStartOfFunctionDef(FnBodyScope, Function);
4688 /// \brief Strips various properties off an implicit instantiation
4689 /// that has just been explicitly specialized.
4690 static void StripImplicitInstantiation(NamedDecl *D) {
4693 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
4694 FD->setInlineSpecified(false);
4698 /// \brief Diagnose cases where we have an explicit template specialization
4699 /// before/after an explicit template instantiation, producing diagnostics
4700 /// for those cases where they are required and determining whether the
4701 /// new specialization/instantiation will have any effect.
4703 /// \param NewLoc the location of the new explicit specialization or
4706 /// \param NewTSK the kind of the new explicit specialization or instantiation.
4708 /// \param PrevDecl the previous declaration of the entity.
4710 /// \param PrevTSK the kind of the old explicit specialization or instantiatin.
4712 /// \param PrevPointOfInstantiation if valid, indicates where the previus
4713 /// declaration was instantiated (either implicitly or explicitly).
4715 /// \param HasNoEffect will be set to true to indicate that the new
4716 /// specialization or instantiation has no effect and should be ignored.
4718 /// \returns true if there was an error that should prevent the introduction of
4719 /// the new declaration into the AST, false otherwise.
4721 Sema::CheckSpecializationInstantiationRedecl(SourceLocation NewLoc,
4722 TemplateSpecializationKind NewTSK,
4723 NamedDecl *PrevDecl,
4724 TemplateSpecializationKind PrevTSK,
4725 SourceLocation PrevPointOfInstantiation,
4726 bool &HasNoEffect) {
4727 HasNoEffect = false;
4730 case TSK_Undeclared:
4731 case TSK_ImplicitInstantiation:
4732 assert(false && "Don't check implicit instantiations here");
4735 case TSK_ExplicitSpecialization:
4737 case TSK_Undeclared:
4738 case TSK_ExplicitSpecialization:
4739 // Okay, we're just specializing something that is either already
4740 // explicitly specialized or has merely been mentioned without any
4744 case TSK_ImplicitInstantiation:
4745 if (PrevPointOfInstantiation.isInvalid()) {
4746 // The declaration itself has not actually been instantiated, so it is
4747 // still okay to specialize it.
4748 StripImplicitInstantiation(PrevDecl);
4753 case TSK_ExplicitInstantiationDeclaration:
4754 case TSK_ExplicitInstantiationDefinition:
4755 assert((PrevTSK == TSK_ImplicitInstantiation ||
4756 PrevPointOfInstantiation.isValid()) &&
4757 "Explicit instantiation without point of instantiation?");
4759 // C++ [temp.expl.spec]p6:
4760 // If a template, a member template or the member of a class template
4761 // is explicitly specialized then that specialization shall be declared
4762 // before the first use of that specialization that would cause an
4763 // implicit instantiation to take place, in every translation unit in
4764 // which such a use occurs; no diagnostic is required.
4765 for (NamedDecl *Prev = PrevDecl; Prev; Prev = getPreviousDecl(Prev)) {
4766 // Is there any previous explicit specialization declaration?
4767 if (getTemplateSpecializationKind(Prev) == TSK_ExplicitSpecialization)
4771 Diag(NewLoc, diag::err_specialization_after_instantiation)
4773 Diag(PrevPointOfInstantiation, diag::note_instantiation_required_here)
4774 << (PrevTSK != TSK_ImplicitInstantiation);
4780 case TSK_ExplicitInstantiationDeclaration:
4782 case TSK_ExplicitInstantiationDeclaration:
4783 // This explicit instantiation declaration is redundant (that's okay).
4787 case TSK_Undeclared:
4788 case TSK_ImplicitInstantiation:
4789 // We're explicitly instantiating something that may have already been
4790 // implicitly instantiated; that's fine.
4793 case TSK_ExplicitSpecialization:
4794 // C++0x [temp.explicit]p4:
4795 // For a given set of template parameters, if an explicit instantiation
4796 // of a template appears after a declaration of an explicit
4797 // specialization for that template, the explicit instantiation has no
4802 case TSK_ExplicitInstantiationDefinition:
4803 // C++0x [temp.explicit]p10:
4804 // If an entity is the subject of both an explicit instantiation
4805 // declaration and an explicit instantiation definition in the same
4806 // translation unit, the definition shall follow the declaration.
4808 diag::err_explicit_instantiation_declaration_after_definition);
4809 Diag(PrevPointOfInstantiation,
4810 diag::note_explicit_instantiation_definition_here);
4811 assert(PrevPointOfInstantiation.isValid() &&
4812 "Explicit instantiation without point of instantiation?");
4818 case TSK_ExplicitInstantiationDefinition:
4820 case TSK_Undeclared:
4821 case TSK_ImplicitInstantiation:
4822 // We're explicitly instantiating something that may have already been
4823 // implicitly instantiated; that's fine.
4826 case TSK_ExplicitSpecialization:
4827 // C++ DR 259, C++0x [temp.explicit]p4:
4828 // For a given set of template parameters, if an explicit
4829 // instantiation of a template appears after a declaration of
4830 // an explicit specialization for that template, the explicit
4831 // instantiation has no effect.
4833 // In C++98/03 mode, we only give an extension warning here, because it
4834 // is not harmful to try to explicitly instantiate something that
4835 // has been explicitly specialized.
4836 if (!getLangOptions().CPlusPlus0x) {
4837 Diag(NewLoc, diag::ext_explicit_instantiation_after_specialization)
4839 Diag(PrevDecl->getLocation(),
4840 diag::note_previous_template_specialization);
4845 case TSK_ExplicitInstantiationDeclaration:
4846 // We're explicity instantiating a definition for something for which we
4847 // were previously asked to suppress instantiations. That's fine.
4850 case TSK_ExplicitInstantiationDefinition:
4851 // C++0x [temp.spec]p5:
4852 // For a given template and a given set of template-arguments,
4853 // - an explicit instantiation definition shall appear at most once
4855 Diag(NewLoc, diag::err_explicit_instantiation_duplicate)
4857 Diag(PrevPointOfInstantiation,
4858 diag::note_previous_explicit_instantiation);
4865 assert(false && "Missing specialization/instantiation case?");
4870 /// \brief Perform semantic analysis for the given dependent function
4871 /// template specialization. The only possible way to get a dependent
4872 /// function template specialization is with a friend declaration,
4875 /// template <class T> void foo(T);
4876 /// template <class T> class A {
4877 /// friend void foo<>(T);
4880 /// There really isn't any useful analysis we can do here, so we
4881 /// just store the information.
4883 Sema::CheckDependentFunctionTemplateSpecialization(FunctionDecl *FD,
4884 const TemplateArgumentListInfo &ExplicitTemplateArgs,
4885 LookupResult &Previous) {
4886 // Remove anything from Previous that isn't a function template in
4887 // the correct context.
4888 DeclContext *FDLookupContext = FD->getDeclContext()->getRedeclContext();
4889 LookupResult::Filter F = Previous.makeFilter();
4890 while (F.hasNext()) {
4891 NamedDecl *D = F.next()->getUnderlyingDecl();
4892 if (!isa<FunctionTemplateDecl>(D) ||
4893 !FDLookupContext->InEnclosingNamespaceSetOf(
4894 D->getDeclContext()->getRedeclContext()))
4899 // Should this be diagnosed here?
4900 if (Previous.empty()) return true;
4902 FD->setDependentTemplateSpecialization(Context, Previous.asUnresolvedSet(),
4903 ExplicitTemplateArgs);
4907 /// \brief Perform semantic analysis for the given function template
4910 /// This routine performs all of the semantic analysis required for an
4911 /// explicit function template specialization. On successful completion,
4912 /// the function declaration \p FD will become a function template
4915 /// \param FD the function declaration, which will be updated to become a
4916 /// function template specialization.
4918 /// \param ExplicitTemplateArgs the explicitly-provided template arguments,
4919 /// if any. Note that this may be valid info even when 0 arguments are
4920 /// explicitly provided as in, e.g., \c void sort<>(char*, char*);
4921 /// as it anyway contains info on the angle brackets locations.
4923 /// \param PrevDecl the set of declarations that may be specialized by
4924 /// this function specialization.
4926 Sema::CheckFunctionTemplateSpecialization(FunctionDecl *FD,
4927 const TemplateArgumentListInfo *ExplicitTemplateArgs,
4928 LookupResult &Previous) {
4929 // The set of function template specializations that could match this
4930 // explicit function template specialization.
4931 UnresolvedSet<8> Candidates;
4933 DeclContext *FDLookupContext = FD->getDeclContext()->getRedeclContext();
4934 for (LookupResult::iterator I = Previous.begin(), E = Previous.end();
4936 NamedDecl *Ovl = (*I)->getUnderlyingDecl();
4937 if (FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(Ovl)) {
4938 // Only consider templates found within the same semantic lookup scope as
4940 if (!FDLookupContext->InEnclosingNamespaceSetOf(
4941 Ovl->getDeclContext()->getRedeclContext()))
4944 // C++ [temp.expl.spec]p11:
4945 // A trailing template-argument can be left unspecified in the
4946 // template-id naming an explicit function template specialization
4947 // provided it can be deduced from the function argument type.
4948 // Perform template argument deduction to determine whether we may be
4949 // specializing this template.
4950 // FIXME: It is somewhat wasteful to build
4951 TemplateDeductionInfo Info(Context, FD->getLocation());
4952 FunctionDecl *Specialization = 0;
4953 if (TemplateDeductionResult TDK
4954 = DeduceTemplateArguments(FunTmpl, ExplicitTemplateArgs,
4958 // FIXME: Template argument deduction failed; record why it failed, so
4959 // that we can provide nifty diagnostics.
4964 // Record this candidate.
4965 Candidates.addDecl(Specialization, I.getAccess());
4969 // Find the most specialized function template.
4970 UnresolvedSetIterator Result
4971 = getMostSpecialized(Candidates.begin(), Candidates.end(),
4972 TPOC_Other, 0, FD->getLocation(),
4973 PDiag(diag::err_function_template_spec_no_match)
4974 << FD->getDeclName(),
4975 PDiag(diag::err_function_template_spec_ambiguous)
4976 << FD->getDeclName() << (ExplicitTemplateArgs != 0),
4977 PDiag(diag::note_function_template_spec_matched));
4978 if (Result == Candidates.end())
4981 // Ignore access information; it doesn't figure into redeclaration checking.
4982 FunctionDecl *Specialization = cast<FunctionDecl>(*Result);
4983 Specialization->setLocation(FD->getLocation());
4985 // FIXME: Check if the prior specialization has a point of instantiation.
4986 // If so, we have run afoul of .
4988 // If this is a friend declaration, then we're not really declaring
4989 // an explicit specialization.
4990 bool isFriend = (FD->getFriendObjectKind() != Decl::FOK_None);
4992 // Check the scope of this explicit specialization.
4994 CheckTemplateSpecializationScope(*this,
4995 Specialization->getPrimaryTemplate(),
4996 Specialization, FD->getLocation(),
5000 // C++ [temp.expl.spec]p6:
5001 // If a template, a member template or the member of a class template is
5002 // explicitly specialized then that specialization shall be declared
5003 // before the first use of that specialization that would cause an implicit
5004 // instantiation to take place, in every translation unit in which such a
5005 // use occurs; no diagnostic is required.
5006 FunctionTemplateSpecializationInfo *SpecInfo
5007 = Specialization->getTemplateSpecializationInfo();
5008 assert(SpecInfo && "Function template specialization info missing?");
5010 bool HasNoEffect = false;
5012 CheckSpecializationInstantiationRedecl(FD->getLocation(),
5013 TSK_ExplicitSpecialization,
5015 SpecInfo->getTemplateSpecializationKind(),
5016 SpecInfo->getPointOfInstantiation(),
5020 // Mark the prior declaration as an explicit specialization, so that later
5021 // clients know that this is an explicit specialization.
5023 SpecInfo->setTemplateSpecializationKind(TSK_ExplicitSpecialization);
5024 MarkUnusedFileScopedDecl(Specialization);
5027 // Turn the given function declaration into a function template
5028 // specialization, with the template arguments from the previous
5030 // Take copies of (semantic and syntactic) template argument lists.
5031 const TemplateArgumentList* TemplArgs = new (Context)
5032 TemplateArgumentList(Specialization->getTemplateSpecializationArgs());
5033 const TemplateArgumentListInfo* TemplArgsAsWritten = ExplicitTemplateArgs
5034 ? new (Context) TemplateArgumentListInfo(*ExplicitTemplateArgs) : 0;
5035 FD->setFunctionTemplateSpecialization(Specialization->getPrimaryTemplate(),
5036 TemplArgs, /*InsertPos=*/0,
5037 SpecInfo->getTemplateSpecializationKind(),
5038 TemplArgsAsWritten);
5040 // The "previous declaration" for this function template specialization is
5041 // the prior function template specialization.
5043 Previous.addDecl(Specialization);
5047 /// \brief Perform semantic analysis for the given non-template member
5050 /// This routine performs all of the semantic analysis required for an
5051 /// explicit member function specialization. On successful completion,
5052 /// the function declaration \p FD will become a member function
5055 /// \param Member the member declaration, which will be updated to become a
5058 /// \param Previous the set of declarations, one of which may be specialized
5059 /// by this function specialization; the set will be modified to contain the
5060 /// redeclared member.
5062 Sema::CheckMemberSpecialization(NamedDecl *Member, LookupResult &Previous) {
5063 assert(!isa<TemplateDecl>(Member) && "Only for non-template members");
5065 // Try to find the member we are instantiating.
5066 NamedDecl *Instantiation = 0;
5067 NamedDecl *InstantiatedFrom = 0;
5068 MemberSpecializationInfo *MSInfo = 0;
5070 if (Previous.empty()) {
5071 // Nowhere to look anyway.
5072 } else if (FunctionDecl *Function = dyn_cast<FunctionDecl>(Member)) {
5073 for (LookupResult::iterator I = Previous.begin(), E = Previous.end();
5075 NamedDecl *D = (*I)->getUnderlyingDecl();
5076 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(D)) {
5077 if (Context.hasSameType(Function->getType(), Method->getType())) {
5078 Instantiation = Method;
5079 InstantiatedFrom = Method->getInstantiatedFromMemberFunction();
5080 MSInfo = Method->getMemberSpecializationInfo();
5085 } else if (isa<VarDecl>(Member)) {
5087 if (Previous.isSingleResult() &&
5088 (PrevVar = dyn_cast<VarDecl>(Previous.getFoundDecl())))
5089 if (PrevVar->isStaticDataMember()) {
5090 Instantiation = PrevVar;
5091 InstantiatedFrom = PrevVar->getInstantiatedFromStaticDataMember();
5092 MSInfo = PrevVar->getMemberSpecializationInfo();
5094 } else if (isa<RecordDecl>(Member)) {
5095 CXXRecordDecl *PrevRecord;
5096 if (Previous.isSingleResult() &&
5097 (PrevRecord = dyn_cast<CXXRecordDecl>(Previous.getFoundDecl()))) {
5098 Instantiation = PrevRecord;
5099 InstantiatedFrom = PrevRecord->getInstantiatedFromMemberClass();
5100 MSInfo = PrevRecord->getMemberSpecializationInfo();
5104 if (!Instantiation) {
5105 // There is no previous declaration that matches. Since member
5106 // specializations are always out-of-line, the caller will complain about
5107 // this mismatch later.
5111 // If this is a friend, just bail out here before we start turning
5112 // things into explicit specializations.
5113 if (Member->getFriendObjectKind() != Decl::FOK_None) {
5114 // Preserve instantiation information.
5115 if (InstantiatedFrom && isa<CXXMethodDecl>(Member)) {
5116 cast<CXXMethodDecl>(Member)->setInstantiationOfMemberFunction(
5117 cast<CXXMethodDecl>(InstantiatedFrom),
5118 cast<CXXMethodDecl>(Instantiation)->getTemplateSpecializationKind());
5119 } else if (InstantiatedFrom && isa<CXXRecordDecl>(Member)) {
5120 cast<CXXRecordDecl>(Member)->setInstantiationOfMemberClass(
5121 cast<CXXRecordDecl>(InstantiatedFrom),
5122 cast<CXXRecordDecl>(Instantiation)->getTemplateSpecializationKind());
5126 Previous.addDecl(Instantiation);
5130 // Make sure that this is a specialization of a member.
5131 if (!InstantiatedFrom) {
5132 Diag(Member->getLocation(), diag::err_spec_member_not_instantiated)
5134 Diag(Instantiation->getLocation(), diag::note_specialized_decl);
5138 // C++ [temp.expl.spec]p6:
5139 // If a template, a member template or the member of a class template is
5140 // explicitly specialized then that spe- cialization shall be declared
5141 // before the first use of that specialization that would cause an implicit
5142 // instantiation to take place, in every translation unit in which such a
5143 // use occurs; no diagnostic is required.
5144 assert(MSInfo && "Member specialization info missing?");
5146 bool HasNoEffect = false;
5147 if (CheckSpecializationInstantiationRedecl(Member->getLocation(),
5148 TSK_ExplicitSpecialization,
5150 MSInfo->getTemplateSpecializationKind(),
5151 MSInfo->getPointOfInstantiation(),
5155 // Check the scope of this explicit specialization.
5156 if (CheckTemplateSpecializationScope(*this,
5158 Instantiation, Member->getLocation(),
5162 // Note that this is an explicit instantiation of a member.
5163 // the original declaration to note that it is an explicit specialization
5164 // (if it was previously an implicit instantiation). This latter step
5165 // makes bookkeeping easier.
5166 if (isa<FunctionDecl>(Member)) {
5167 FunctionDecl *InstantiationFunction = cast<FunctionDecl>(Instantiation);
5168 if (InstantiationFunction->getTemplateSpecializationKind() ==
5169 TSK_ImplicitInstantiation) {
5170 InstantiationFunction->setTemplateSpecializationKind(
5171 TSK_ExplicitSpecialization);
5172 InstantiationFunction->setLocation(Member->getLocation());
5175 cast<FunctionDecl>(Member)->setInstantiationOfMemberFunction(
5176 cast<CXXMethodDecl>(InstantiatedFrom),
5177 TSK_ExplicitSpecialization);
5178 MarkUnusedFileScopedDecl(InstantiationFunction);
5179 } else if (isa<VarDecl>(Member)) {
5180 VarDecl *InstantiationVar = cast<VarDecl>(Instantiation);
5181 if (InstantiationVar->getTemplateSpecializationKind() ==
5182 TSK_ImplicitInstantiation) {
5183 InstantiationVar->setTemplateSpecializationKind(
5184 TSK_ExplicitSpecialization);
5185 InstantiationVar->setLocation(Member->getLocation());
5188 Context.setInstantiatedFromStaticDataMember(cast<VarDecl>(Member),
5189 cast<VarDecl>(InstantiatedFrom),
5190 TSK_ExplicitSpecialization);
5191 MarkUnusedFileScopedDecl(InstantiationVar);
5193 assert(isa<CXXRecordDecl>(Member) && "Only member classes remain");
5194 CXXRecordDecl *InstantiationClass = cast<CXXRecordDecl>(Instantiation);
5195 if (InstantiationClass->getTemplateSpecializationKind() ==
5196 TSK_ImplicitInstantiation) {
5197 InstantiationClass->setTemplateSpecializationKind(
5198 TSK_ExplicitSpecialization);
5199 InstantiationClass->setLocation(Member->getLocation());
5202 cast<CXXRecordDecl>(Member)->setInstantiationOfMemberClass(
5203 cast<CXXRecordDecl>(InstantiatedFrom),
5204 TSK_ExplicitSpecialization);
5207 // Save the caller the trouble of having to figure out which declaration
5208 // this specialization matches.
5210 Previous.addDecl(Instantiation);
5214 /// \brief Check the scope of an explicit instantiation.
5216 /// \returns true if a serious error occurs, false otherwise.
5217 static bool CheckExplicitInstantiationScope(Sema &S, NamedDecl *D,
5218 SourceLocation InstLoc,
5219 bool WasQualifiedName) {
5220 DeclContext *OrigContext= D->getDeclContext()->getEnclosingNamespaceContext();
5221 DeclContext *CurContext = S.CurContext->getRedeclContext();
5223 if (CurContext->isRecord()) {
5224 S.Diag(InstLoc, diag::err_explicit_instantiation_in_class)
5229 // C++0x [temp.explicit]p2:
5230 // An explicit instantiation shall appear in an enclosing namespace of its
5233 // This is DR275, which we do not retroactively apply to C++98/03.
5234 if (S.getLangOptions().CPlusPlus0x &&
5235 !CurContext->Encloses(OrigContext)) {
5236 if (NamespaceDecl *NS = dyn_cast<NamespaceDecl>(OrigContext))
5238 S.getLangOptions().CPlusPlus0x?
5239 diag::err_explicit_instantiation_out_of_scope
5240 : diag::warn_explicit_instantiation_out_of_scope_0x)
5244 S.getLangOptions().CPlusPlus0x?
5245 diag::err_explicit_instantiation_must_be_global
5246 : diag::warn_explicit_instantiation_out_of_scope_0x)
5248 S.Diag(D->getLocation(), diag::note_explicit_instantiation_here);
5252 // C++0x [temp.explicit]p2:
5253 // If the name declared in the explicit instantiation is an unqualified
5254 // name, the explicit instantiation shall appear in the namespace where
5255 // its template is declared or, if that namespace is inline (7.3.1), any
5256 // namespace from its enclosing namespace set.
5257 if (WasQualifiedName)
5260 if (CurContext->InEnclosingNamespaceSetOf(OrigContext))
5264 S.getLangOptions().CPlusPlus0x?
5265 diag::err_explicit_instantiation_unqualified_wrong_namespace
5266 : diag::warn_explicit_instantiation_unqualified_wrong_namespace_0x)
5267 << D << OrigContext;
5268 S.Diag(D->getLocation(), diag::note_explicit_instantiation_here);
5272 /// \brief Determine whether the given scope specifier has a template-id in it.
5273 static bool ScopeSpecifierHasTemplateId(const CXXScopeSpec &SS) {
5277 // C++0x [temp.explicit]p2:
5278 // If the explicit instantiation is for a member function, a member class
5279 // or a static data member of a class template specialization, the name of
5280 // the class template specialization in the qualified-id for the member
5281 // name shall be a simple-template-id.
5283 // C++98 has the same restriction, just worded differently.
5284 for (NestedNameSpecifier *NNS = (NestedNameSpecifier *)SS.getScopeRep();
5285 NNS; NNS = NNS->getPrefix())
5286 if (const Type *T = NNS->getAsType())
5287 if (isa<TemplateSpecializationType>(T))
5293 // Explicit instantiation of a class template specialization
5295 Sema::ActOnExplicitInstantiation(Scope *S,
5296 SourceLocation ExternLoc,
5297 SourceLocation TemplateLoc,
5299 SourceLocation KWLoc,
5300 const CXXScopeSpec &SS,
5301 TemplateTy TemplateD,
5302 SourceLocation TemplateNameLoc,
5303 SourceLocation LAngleLoc,
5304 ASTTemplateArgsPtr TemplateArgsIn,
5305 SourceLocation RAngleLoc,
5306 AttributeList *Attr) {
5307 // Find the class template we're specializing
5308 TemplateName Name = TemplateD.getAsVal<TemplateName>();
5309 ClassTemplateDecl *ClassTemplate
5310 = cast<ClassTemplateDecl>(Name.getAsTemplateDecl());
5312 // Check that the specialization uses the same tag kind as the
5313 // original template.
5314 TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec);
5315 assert(Kind != TTK_Enum &&
5316 "Invalid enum tag in class template explicit instantiation!");
5317 if (!isAcceptableTagRedeclaration(ClassTemplate->getTemplatedDecl(),
5319 *ClassTemplate->getIdentifier())) {
5320 Diag(KWLoc, diag::err_use_with_wrong_tag)
5322 << FixItHint::CreateReplacement(KWLoc,
5323 ClassTemplate->getTemplatedDecl()->getKindName());
5324 Diag(ClassTemplate->getTemplatedDecl()->getLocation(),
5325 diag::note_previous_use);
5326 Kind = ClassTemplate->getTemplatedDecl()->getTagKind();
5329 // C++0x [temp.explicit]p2:
5330 // There are two forms of explicit instantiation: an explicit instantiation
5331 // definition and an explicit instantiation declaration. An explicit
5332 // instantiation declaration begins with the extern keyword. [...]
5333 TemplateSpecializationKind TSK
5334 = ExternLoc.isInvalid()? TSK_ExplicitInstantiationDefinition
5335 : TSK_ExplicitInstantiationDeclaration;
5337 // Translate the parser's template argument list in our AST format.
5338 TemplateArgumentListInfo TemplateArgs(LAngleLoc, RAngleLoc);
5339 translateTemplateArguments(TemplateArgsIn, TemplateArgs);
5341 // Check that the template argument list is well-formed for this
5343 llvm::SmallVector<TemplateArgument, 4> Converted;
5344 if (CheckTemplateArgumentList(ClassTemplate, TemplateNameLoc,
5345 TemplateArgs, false, Converted))
5348 assert((Converted.size() == ClassTemplate->getTemplateParameters()->size()) &&
5349 "Converted template argument list is too short!");
5351 // Find the class template specialization declaration that
5352 // corresponds to these arguments.
5353 void *InsertPos = 0;
5354 ClassTemplateSpecializationDecl *PrevDecl
5355 = ClassTemplate->findSpecialization(Converted.data(),
5356 Converted.size(), InsertPos);
5358 TemplateSpecializationKind PrevDecl_TSK
5359 = PrevDecl ? PrevDecl->getTemplateSpecializationKind() : TSK_Undeclared;
5361 // C++0x [temp.explicit]p2:
5362 // [...] An explicit instantiation shall appear in an enclosing
5363 // namespace of its template. [...]
5365 // This is C++ DR 275.
5366 if (CheckExplicitInstantiationScope(*this, ClassTemplate, TemplateNameLoc,
5370 ClassTemplateSpecializationDecl *Specialization = 0;
5372 bool HasNoEffect = false;
5374 if (CheckSpecializationInstantiationRedecl(TemplateNameLoc, TSK,
5375 PrevDecl, PrevDecl_TSK,
5376 PrevDecl->getPointOfInstantiation(),
5380 // Even though HasNoEffect == true means that this explicit instantiation
5381 // has no effect on semantics, we go on to put its syntax in the AST.
5383 if (PrevDecl_TSK == TSK_ImplicitInstantiation ||
5384 PrevDecl_TSK == TSK_Undeclared) {
5385 // Since the only prior class template specialization with these
5386 // arguments was referenced but not declared, reuse that
5387 // declaration node as our own, updating the source location
5388 // for the template name to reflect our new declaration.
5389 // (Other source locations will be updated later.)
5390 Specialization = PrevDecl;
5391 Specialization->setLocation(TemplateNameLoc);
5396 if (!Specialization) {
5397 // Create a new class template specialization declaration node for
5398 // this explicit specialization.
5400 = ClassTemplateSpecializationDecl::Create(Context, Kind,
5401 ClassTemplate->getDeclContext(),
5407 SetNestedNameSpecifier(Specialization, SS);
5409 if (!HasNoEffect && !PrevDecl) {
5410 // Insert the new specialization.
5411 ClassTemplate->AddSpecialization(Specialization, InsertPos);
5415 // Build the fully-sugared type for this explicit instantiation as
5416 // the user wrote in the explicit instantiation itself. This means
5417 // that we'll pretty-print the type retrieved from the
5418 // specialization's declaration the way that the user actually wrote
5419 // the explicit instantiation, rather than formatting the name based
5420 // on the "canonical" representation used to store the template
5421 // arguments in the specialization.
5422 TypeSourceInfo *WrittenTy
5423 = Context.getTemplateSpecializationTypeInfo(Name, TemplateNameLoc,
5425 Context.getTypeDeclType(Specialization));
5426 Specialization->setTypeAsWritten(WrittenTy);
5427 TemplateArgsIn.release();
5429 // Set source locations for keywords.
5430 Specialization->setExternLoc(ExternLoc);
5431 Specialization->setTemplateKeywordLoc(TemplateLoc);
5433 // Add the explicit instantiation into its lexical context. However,
5434 // since explicit instantiations are never found by name lookup, we
5435 // just put it into the declaration context directly.
5436 Specialization->setLexicalDeclContext(CurContext);
5437 CurContext->addDecl(Specialization);
5439 // Syntax is now OK, so return if it has no other effect on semantics.
5441 // Set the template specialization kind.
5442 Specialization->setTemplateSpecializationKind(TSK);
5443 return Specialization;
5446 // C++ [temp.explicit]p3:
5447 // A definition of a class template or class member template
5448 // shall be in scope at the point of the explicit instantiation of
5449 // the class template or class member template.
5451 // This check comes when we actually try to perform the
5453 ClassTemplateSpecializationDecl *Def
5454 = cast_or_null<ClassTemplateSpecializationDecl>(
5455 Specialization->getDefinition());
5457 InstantiateClassTemplateSpecialization(TemplateNameLoc, Specialization, TSK);
5458 else if (TSK == TSK_ExplicitInstantiationDefinition) {
5459 MarkVTableUsed(TemplateNameLoc, Specialization, true);
5460 Specialization->setPointOfInstantiation(Def->getPointOfInstantiation());
5463 // Instantiate the members of this class template specialization.
5464 Def = cast_or_null<ClassTemplateSpecializationDecl>(
5465 Specialization->getDefinition());
5467 TemplateSpecializationKind Old_TSK = Def->getTemplateSpecializationKind();
5469 // Fix a TSK_ExplicitInstantiationDeclaration followed by a
5470 // TSK_ExplicitInstantiationDefinition
5471 if (Old_TSK == TSK_ExplicitInstantiationDeclaration &&
5472 TSK == TSK_ExplicitInstantiationDefinition)
5473 Def->setTemplateSpecializationKind(TSK);
5475 InstantiateClassTemplateSpecializationMembers(TemplateNameLoc, Def, TSK);
5478 // Set the template specialization kind.
5479 Specialization->setTemplateSpecializationKind(TSK);
5480 return Specialization;
5483 // Explicit instantiation of a member class of a class template.
5485 Sema::ActOnExplicitInstantiation(Scope *S,
5486 SourceLocation ExternLoc,
5487 SourceLocation TemplateLoc,
5489 SourceLocation KWLoc,
5491 IdentifierInfo *Name,
5492 SourceLocation NameLoc,
5493 AttributeList *Attr) {
5496 bool IsDependent = false;
5497 Decl *TagD = ActOnTag(S, TagSpec, Sema::TUK_Reference,
5498 KWLoc, SS, Name, NameLoc, Attr, AS_none,
5499 MultiTemplateParamsArg(*this, 0, 0),
5500 Owned, IsDependent, false, false,
5502 assert(!IsDependent && "explicit instantiation of dependent name not yet handled");
5507 TagDecl *Tag = cast<TagDecl>(TagD);
5508 if (Tag->isEnum()) {
5509 Diag(TemplateLoc, diag::err_explicit_instantiation_enum)
5510 << Context.getTypeDeclType(Tag);
5514 if (Tag->isInvalidDecl())
5517 CXXRecordDecl *Record = cast<CXXRecordDecl>(Tag);
5518 CXXRecordDecl *Pattern = Record->getInstantiatedFromMemberClass();
5520 Diag(TemplateLoc, diag::err_explicit_instantiation_nontemplate_type)
5521 << Context.getTypeDeclType(Record);
5522 Diag(Record->getLocation(), diag::note_nontemplate_decl_here);
5526 // C++0x [temp.explicit]p2:
5527 // If the explicit instantiation is for a class or member class, the
5528 // elaborated-type-specifier in the declaration shall include a
5529 // simple-template-id.
5531 // C++98 has the same restriction, just worded differently.
5532 if (!ScopeSpecifierHasTemplateId(SS))
5533 Diag(TemplateLoc, diag::ext_explicit_instantiation_without_qualified_id)
5534 << Record << SS.getRange();
5536 // C++0x [temp.explicit]p2:
5537 // There are two forms of explicit instantiation: an explicit instantiation
5538 // definition and an explicit instantiation declaration. An explicit
5539 // instantiation declaration begins with the extern keyword. [...]
5540 TemplateSpecializationKind TSK
5541 = ExternLoc.isInvalid()? TSK_ExplicitInstantiationDefinition
5542 : TSK_ExplicitInstantiationDeclaration;
5544 // C++0x [temp.explicit]p2:
5545 // [...] An explicit instantiation shall appear in an enclosing
5546 // namespace of its template. [...]
5548 // This is C++ DR 275.
5549 CheckExplicitInstantiationScope(*this, Record, NameLoc, true);
5551 // Verify that it is okay to explicitly instantiate here.
5552 CXXRecordDecl *PrevDecl
5553 = cast_or_null<CXXRecordDecl>(Record->getPreviousDeclaration());
5554 if (!PrevDecl && Record->getDefinition())
5557 MemberSpecializationInfo *MSInfo = PrevDecl->getMemberSpecializationInfo();
5558 bool HasNoEffect = false;
5559 assert(MSInfo && "No member specialization information?");
5560 if (CheckSpecializationInstantiationRedecl(TemplateLoc, TSK,
5562 MSInfo->getTemplateSpecializationKind(),
5563 MSInfo->getPointOfInstantiation(),
5570 CXXRecordDecl *RecordDef
5571 = cast_or_null<CXXRecordDecl>(Record->getDefinition());
5573 // C++ [temp.explicit]p3:
5574 // A definition of a member class of a class template shall be in scope
5575 // at the point of an explicit instantiation of the member class.
5577 = cast_or_null<CXXRecordDecl>(Pattern->getDefinition());
5579 Diag(TemplateLoc, diag::err_explicit_instantiation_undefined_member)
5580 << 0 << Record->getDeclName() << Record->getDeclContext();
5581 Diag(Pattern->getLocation(), diag::note_forward_declaration)
5585 if (InstantiateClass(NameLoc, Record, Def,
5586 getTemplateInstantiationArgs(Record),
5590 RecordDef = cast_or_null<CXXRecordDecl>(Record->getDefinition());
5596 // Instantiate all of the members of the class.
5597 InstantiateClassMembers(NameLoc, RecordDef,
5598 getTemplateInstantiationArgs(Record), TSK);
5600 if (TSK == TSK_ExplicitInstantiationDefinition)
5601 MarkVTableUsed(NameLoc, RecordDef, true);
5603 // FIXME: We don't have any representation for explicit instantiations of
5604 // member classes. Such a representation is not needed for compilation, but it
5605 // should be available for clients that want to see all of the declarations in
5610 DeclResult Sema::ActOnExplicitInstantiation(Scope *S,
5611 SourceLocation ExternLoc,
5612 SourceLocation TemplateLoc,
5614 // Explicit instantiations always require a name.
5615 // TODO: check if/when DNInfo should replace Name.
5616 DeclarationNameInfo NameInfo = GetNameForDeclarator(D);
5617 DeclarationName Name = NameInfo.getName();
5619 if (!D.isInvalidType())
5620 Diag(D.getDeclSpec().getSourceRange().getBegin(),
5621 diag::err_explicit_instantiation_requires_name)
5622 << D.getDeclSpec().getSourceRange()
5623 << D.getSourceRange();
5628 // The scope passed in may not be a decl scope. Zip up the scope tree until
5629 // we find one that is.
5630 while ((S->getFlags() & Scope::DeclScope) == 0 ||
5631 (S->getFlags() & Scope::TemplateParamScope) != 0)
5634 // Determine the type of the declaration.
5635 TypeSourceInfo *T = GetTypeForDeclarator(D, S);
5636 QualType R = T->getType();
5640 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) {
5641 // Cannot explicitly instantiate a typedef.
5642 Diag(D.getIdentifierLoc(), diag::err_explicit_instantiation_of_typedef)
5647 // C++0x [temp.explicit]p1:
5648 // [...] An explicit instantiation of a function template shall not use the
5649 // inline or constexpr specifiers.
5650 // Presumably, this also applies to member functions of class templates as
5652 if (D.getDeclSpec().isInlineSpecified() && getLangOptions().CPlusPlus0x)
5653 Diag(D.getDeclSpec().getInlineSpecLoc(),
5654 diag::err_explicit_instantiation_inline)
5655 <<FixItHint::CreateRemoval(D.getDeclSpec().getInlineSpecLoc());
5657 // FIXME: check for constexpr specifier.
5659 // C++0x [temp.explicit]p2:
5660 // There are two forms of explicit instantiation: an explicit instantiation
5661 // definition and an explicit instantiation declaration. An explicit
5662 // instantiation declaration begins with the extern keyword. [...]
5663 TemplateSpecializationKind TSK
5664 = ExternLoc.isInvalid()? TSK_ExplicitInstantiationDefinition
5665 : TSK_ExplicitInstantiationDeclaration;
5667 LookupResult Previous(*this, NameInfo, LookupOrdinaryName);
5668 LookupParsedName(Previous, S, &D.getCXXScopeSpec());
5670 if (!R->isFunctionType()) {
5671 // C++ [temp.explicit]p1:
5672 // A [...] static data member of a class template can be explicitly
5673 // instantiated from the member definition associated with its class
5675 if (Previous.isAmbiguous())
5678 VarDecl *Prev = Previous.getAsSingle<VarDecl>();
5679 if (!Prev || !Prev->isStaticDataMember()) {
5680 // We expect to see a data data member here.
5681 Diag(D.getIdentifierLoc(), diag::err_explicit_instantiation_not_known)
5683 for (LookupResult::iterator P = Previous.begin(), PEnd = Previous.end();
5685 Diag((*P)->getLocation(), diag::note_explicit_instantiation_here);
5689 if (!Prev->getInstantiatedFromStaticDataMember()) {
5690 // FIXME: Check for explicit specialization?
5691 Diag(D.getIdentifierLoc(),
5692 diag::err_explicit_instantiation_data_member_not_instantiated)
5694 Diag(Prev->getLocation(), diag::note_explicit_instantiation_here);
5695 // FIXME: Can we provide a note showing where this was declared?
5699 // C++0x [temp.explicit]p2:
5700 // If the explicit instantiation is for a member function, a member class
5701 // or a static data member of a class template specialization, the name of
5702 // the class template specialization in the qualified-id for the member
5703 // name shall be a simple-template-id.
5705 // C++98 has the same restriction, just worded differently.
5706 if (!ScopeSpecifierHasTemplateId(D.getCXXScopeSpec()))
5707 Diag(D.getIdentifierLoc(),
5708 diag::ext_explicit_instantiation_without_qualified_id)
5709 << Prev << D.getCXXScopeSpec().getRange();
5711 // Check the scope of this explicit instantiation.
5712 CheckExplicitInstantiationScope(*this, Prev, D.getIdentifierLoc(), true);
5714 // Verify that it is okay to explicitly instantiate here.
5715 MemberSpecializationInfo *MSInfo = Prev->getMemberSpecializationInfo();
5716 assert(MSInfo && "Missing static data member specialization info?");
5717 bool HasNoEffect = false;
5718 if (CheckSpecializationInstantiationRedecl(D.getIdentifierLoc(), TSK, Prev,
5719 MSInfo->getTemplateSpecializationKind(),
5720 MSInfo->getPointOfInstantiation(),
5726 // Instantiate static data member.
5727 Prev->setTemplateSpecializationKind(TSK, D.getIdentifierLoc());
5728 if (TSK == TSK_ExplicitInstantiationDefinition)
5729 InstantiateStaticDataMemberDefinition(D.getIdentifierLoc(), Prev);
5731 // FIXME: Create an ExplicitInstantiation node?
5735 // If the declarator is a template-id, translate the parser's template
5736 // argument list into our AST format.
5737 bool HasExplicitTemplateArgs = false;
5738 TemplateArgumentListInfo TemplateArgs;
5739 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) {
5740 TemplateIdAnnotation *TemplateId = D.getName().TemplateId;
5741 TemplateArgs.setLAngleLoc(TemplateId->LAngleLoc);
5742 TemplateArgs.setRAngleLoc(TemplateId->RAngleLoc);
5743 ASTTemplateArgsPtr TemplateArgsPtr(*this,
5744 TemplateId->getTemplateArgs(),
5745 TemplateId->NumArgs);
5746 translateTemplateArguments(TemplateArgsPtr, TemplateArgs);
5747 HasExplicitTemplateArgs = true;
5748 TemplateArgsPtr.release();
5751 // C++ [temp.explicit]p1:
5752 // A [...] function [...] can be explicitly instantiated from its template.
5753 // A member function [...] of a class template can be explicitly
5754 // instantiated from the member definition associated with its class
5756 UnresolvedSet<8> Matches;
5757 for (LookupResult::iterator P = Previous.begin(), PEnd = Previous.end();
5759 NamedDecl *Prev = *P;
5760 if (!HasExplicitTemplateArgs) {
5761 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Prev)) {
5762 if (Context.hasSameUnqualifiedType(Method->getType(), R)) {
5765 Matches.addDecl(Method, P.getAccess());
5766 if (Method->getTemplateSpecializationKind() == TSK_Undeclared)
5772 FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(Prev);
5776 TemplateDeductionInfo Info(Context, D.getIdentifierLoc());
5777 FunctionDecl *Specialization = 0;
5778 if (TemplateDeductionResult TDK
5779 = DeduceTemplateArguments(FunTmpl,
5780 (HasExplicitTemplateArgs ? &TemplateArgs : 0),
5781 R, Specialization, Info)) {
5782 // FIXME: Keep track of almost-matches?
5787 Matches.addDecl(Specialization, P.getAccess());
5790 // Find the most specialized function template specialization.
5791 UnresolvedSetIterator Result
5792 = getMostSpecialized(Matches.begin(), Matches.end(), TPOC_Other, 0,
5793 D.getIdentifierLoc(),
5794 PDiag(diag::err_explicit_instantiation_not_known) << Name,
5795 PDiag(diag::err_explicit_instantiation_ambiguous) << Name,
5796 PDiag(diag::note_explicit_instantiation_candidate));
5798 if (Result == Matches.end())
5801 // Ignore access control bits, we don't need them for redeclaration checking.
5802 FunctionDecl *Specialization = cast<FunctionDecl>(*Result);
5804 if (Specialization->getTemplateSpecializationKind() == TSK_Undeclared) {
5805 Diag(D.getIdentifierLoc(),
5806 diag::err_explicit_instantiation_member_function_not_instantiated)
5808 << (Specialization->getTemplateSpecializationKind() ==
5809 TSK_ExplicitSpecialization);
5810 Diag(Specialization->getLocation(), diag::note_explicit_instantiation_here);
5814 FunctionDecl *PrevDecl = Specialization->getPreviousDeclaration();
5815 if (!PrevDecl && Specialization->isThisDeclarationADefinition())
5816 PrevDecl = Specialization;
5819 bool HasNoEffect = false;
5820 if (CheckSpecializationInstantiationRedecl(D.getIdentifierLoc(), TSK,
5822 PrevDecl->getTemplateSpecializationKind(),
5823 PrevDecl->getPointOfInstantiation(),
5827 // FIXME: We may still want to build some representation of this
5828 // explicit specialization.
5833 Specialization->setTemplateSpecializationKind(TSK, D.getIdentifierLoc());
5835 if (TSK == TSK_ExplicitInstantiationDefinition)
5836 InstantiateFunctionDefinition(D.getIdentifierLoc(), Specialization);
5838 // C++0x [temp.explicit]p2:
5839 // If the explicit instantiation is for a member function, a member class
5840 // or a static data member of a class template specialization, the name of
5841 // the class template specialization in the qualified-id for the member
5842 // name shall be a simple-template-id.
5844 // C++98 has the same restriction, just worded differently.
5845 FunctionTemplateDecl *FunTmpl = Specialization->getPrimaryTemplate();
5846 if (D.getName().getKind() != UnqualifiedId::IK_TemplateId && !FunTmpl &&
5847 D.getCXXScopeSpec().isSet() &&
5848 !ScopeSpecifierHasTemplateId(D.getCXXScopeSpec()))
5849 Diag(D.getIdentifierLoc(),
5850 diag::ext_explicit_instantiation_without_qualified_id)
5851 << Specialization << D.getCXXScopeSpec().getRange();
5853 CheckExplicitInstantiationScope(*this,
5854 FunTmpl? (NamedDecl *)FunTmpl
5855 : Specialization->getInstantiatedFromMemberFunction(),
5856 D.getIdentifierLoc(),
5857 D.getCXXScopeSpec().isSet());
5859 // FIXME: Create some kind of ExplicitInstantiationDecl here.
5864 Sema::ActOnDependentTag(Scope *S, unsigned TagSpec, TagUseKind TUK,
5865 const CXXScopeSpec &SS, IdentifierInfo *Name,
5866 SourceLocation TagLoc, SourceLocation NameLoc) {
5867 // This has to hold, because SS is expected to be defined.
5868 assert(Name && "Expected a name in a dependent tag");
5870 NestedNameSpecifier *NNS
5871 = static_cast<NestedNameSpecifier *>(SS.getScopeRep());
5875 TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec);
5877 if (TUK == TUK_Declaration || TUK == TUK_Definition) {
5878 Diag(NameLoc, diag::err_dependent_tag_decl)
5879 << (TUK == TUK_Definition) << Kind << SS.getRange();
5883 ElaboratedTypeKeyword Kwd = TypeWithKeyword::getKeywordForTagTypeKind(Kind);
5884 return ParsedType::make(Context.getDependentNameType(Kwd, NNS, Name));
5888 Sema::ActOnTypenameType(Scope *S, SourceLocation TypenameLoc,
5889 const CXXScopeSpec &SS, const IdentifierInfo &II,
5890 SourceLocation IdLoc) {
5891 NestedNameSpecifier *NNS
5892 = static_cast<NestedNameSpecifier *>(SS.getScopeRep());
5896 if (TypenameLoc.isValid() && S && !S->getTemplateParamParent() &&
5897 !getLangOptions().CPlusPlus0x)
5898 Diag(TypenameLoc, diag::ext_typename_outside_of_template)
5899 << FixItHint::CreateRemoval(TypenameLoc);
5901 QualType T = CheckTypenameType(ETK_Typename, NNS, II,
5902 TypenameLoc, SS.getRange(), IdLoc);
5906 TypeSourceInfo *TSI = Context.CreateTypeSourceInfo(T);
5907 if (isa<DependentNameType>(T)) {
5908 DependentNameTypeLoc TL = cast<DependentNameTypeLoc>(TSI->getTypeLoc());
5909 TL.setKeywordLoc(TypenameLoc);
5910 TL.setQualifierRange(SS.getRange());
5911 TL.setNameLoc(IdLoc);
5913 ElaboratedTypeLoc TL = cast<ElaboratedTypeLoc>(TSI->getTypeLoc());
5914 TL.setKeywordLoc(TypenameLoc);
5915 TL.setQualifierRange(SS.getRange());
5916 cast<TypeSpecTypeLoc>(TL.getNamedTypeLoc()).setNameLoc(IdLoc);
5919 return CreateParsedType(T, TSI);
5923 Sema::ActOnTypenameType(Scope *S, SourceLocation TypenameLoc,
5924 const CXXScopeSpec &SS, SourceLocation TemplateLoc,
5926 if (TypenameLoc.isValid() && S && !S->getTemplateParamParent() &&
5927 !getLangOptions().CPlusPlus0x)
5928 Diag(TypenameLoc, diag::ext_typename_outside_of_template)
5929 << FixItHint::CreateRemoval(TypenameLoc);
5931 TypeSourceInfo *InnerTSI = 0;
5932 QualType T = GetTypeFromParser(Ty, &InnerTSI);
5934 assert(isa<TemplateSpecializationType>(T) &&
5935 "Expected a template specialization type");
5937 if (computeDeclContext(SS, false)) {
5938 // If we can compute a declaration context, then the "typename"
5939 // keyword was superfluous. Just build an ElaboratedType to keep
5940 // track of the nested-name-specifier.
5942 // Push the inner type, preserving its source locations if possible.
5943 TypeLocBuilder Builder;
5945 Builder.pushFullCopy(InnerTSI->getTypeLoc());
5947 Builder.push<TemplateSpecializationTypeLoc>(T).initialize(Context,
5950 /* Note: NNS already embedded in template specialization type T. */
5951 T = Context.getElaboratedType(ETK_Typename, /*NNS=*/0, T);
5952 ElaboratedTypeLoc TL = Builder.push<ElaboratedTypeLoc>(T);
5953 TL.setKeywordLoc(TypenameLoc);
5954 TL.setQualifierRange(SS.getRange());
5956 TypeSourceInfo *TSI = Builder.getTypeSourceInfo(Context, T);
5957 return CreateParsedType(T, TSI);
5960 // TODO: it's really silly that we make a template specialization
5961 // type earlier only to drop it again here.
5962 const TemplateSpecializationType *TST = cast<TemplateSpecializationType>(T);
5963 DependentTemplateName *DTN =
5964 TST->getTemplateName().getAsDependentTemplateName();
5965 assert(DTN && "dependent template has non-dependent name?");
5966 assert(DTN->getQualifier()
5967 == static_cast<NestedNameSpecifier*>(SS.getScopeRep()));
5968 T = Context.getDependentTemplateSpecializationType(ETK_Typename,
5969 DTN->getQualifier(),
5970 DTN->getIdentifier(),
5973 TypeSourceInfo *TSI = Context.CreateTypeSourceInfo(T);
5974 DependentTemplateSpecializationTypeLoc TL =
5975 cast<DependentTemplateSpecializationTypeLoc>(TSI->getTypeLoc());
5977 TemplateSpecializationTypeLoc TSTL =
5978 cast<TemplateSpecializationTypeLoc>(InnerTSI->getTypeLoc());
5979 TL.setLAngleLoc(TSTL.getLAngleLoc());
5980 TL.setRAngleLoc(TSTL.getRAngleLoc());
5981 for (unsigned I = 0, E = TST->getNumArgs(); I != E; ++I)
5982 TL.setArgLocInfo(I, TSTL.getArgLocInfo(I));
5984 // FIXME: Poor source-location information here.
5985 TL.initializeLocal(Context, TemplateLoc);
5987 TL.setKeywordLoc(TypenameLoc);
5988 TL.setQualifierRange(SS.getRange());
5989 return CreateParsedType(T, TSI);
5992 /// \brief Build the type that describes a C++ typename specifier,
5993 /// e.g., "typename T::type".
5995 Sema::CheckTypenameType(ElaboratedTypeKeyword Keyword,
5996 NestedNameSpecifier *NNS, const IdentifierInfo &II,
5997 SourceLocation KeywordLoc, SourceRange NNSRange,
5998 SourceLocation IILoc) {
6000 SS.setScopeRep(NNS);
6001 SS.setRange(NNSRange);
6003 DeclContext *Ctx = computeDeclContext(SS);
6005 // If the nested-name-specifier is dependent and couldn't be
6006 // resolved to a type, build a typename type.
6007 assert(NNS->isDependent());
6008 return Context.getDependentNameType(Keyword, NNS, &II);
6011 // If the nested-name-specifier refers to the current instantiation,
6012 // the "typename" keyword itself is superfluous. In C++03, the
6013 // program is actually ill-formed. However, DR 382 (in C++0x CD1)
6014 // allows such extraneous "typename" keywords, and we retroactively
6015 // apply this DR to C++03 code with only a warning. In any case we continue.
6017 if (RequireCompleteDeclContext(SS, Ctx))
6020 DeclarationName Name(&II);
6021 LookupResult Result(*this, Name, IILoc, LookupOrdinaryName);
6022 LookupQualifiedName(Result, Ctx);
6023 unsigned DiagID = 0;
6024 Decl *Referenced = 0;
6025 switch (Result.getResultKind()) {
6026 case LookupResult::NotFound:
6027 DiagID = diag::err_typename_nested_not_found;
6030 case LookupResult::FoundUnresolvedValue: {
6031 // We found a using declaration that is a value. Most likely, the using
6032 // declaration itself is meant to have the 'typename' keyword.
6033 SourceRange FullRange(KeywordLoc.isValid() ? KeywordLoc : NNSRange.getBegin(),
6035 Diag(IILoc, diag::err_typename_refers_to_using_value_decl)
6036 << Name << Ctx << FullRange;
6037 if (UnresolvedUsingValueDecl *Using
6038 = dyn_cast<UnresolvedUsingValueDecl>(Result.getRepresentativeDecl())){
6039 SourceLocation Loc = Using->getTargetNestedNameRange().getBegin();
6040 Diag(Loc, diag::note_using_value_decl_missing_typename)
6041 << FixItHint::CreateInsertion(Loc, "typename ");
6044 // Fall through to create a dependent typename type, from which we can recover
6047 case LookupResult::NotFoundInCurrentInstantiation:
6048 // Okay, it's a member of an unknown instantiation.
6049 return Context.getDependentNameType(Keyword, NNS, &II);
6051 case LookupResult::Found:
6052 if (TypeDecl *Type = dyn_cast<TypeDecl>(Result.getFoundDecl())) {
6053 // We found a type. Build an ElaboratedType, since the
6054 // typename-specifier was just sugar.
6055 return Context.getElaboratedType(ETK_Typename, NNS,
6056 Context.getTypeDeclType(Type));
6059 DiagID = diag::err_typename_nested_not_type;
6060 Referenced = Result.getFoundDecl();
6064 llvm_unreachable("unresolved using decl in non-dependent context");
6067 case LookupResult::FoundOverloaded:
6068 DiagID = diag::err_typename_nested_not_type;
6069 Referenced = *Result.begin();
6072 case LookupResult::Ambiguous:
6076 // If we get here, it's because name lookup did not find a
6077 // type. Emit an appropriate diagnostic and return an error.
6078 SourceRange FullRange(KeywordLoc.isValid() ? KeywordLoc : NNSRange.getBegin(),
6080 Diag(IILoc, DiagID) << FullRange << Name << Ctx;
6082 Diag(Referenced->getLocation(), diag::note_typename_refers_here)
6088 // See Sema::RebuildTypeInCurrentInstantiation
6089 class CurrentInstantiationRebuilder
6090 : public TreeTransform<CurrentInstantiationRebuilder> {
6092 DeclarationName Entity;
6095 typedef TreeTransform<CurrentInstantiationRebuilder> inherited;
6097 CurrentInstantiationRebuilder(Sema &SemaRef,
6099 DeclarationName Entity)
6100 : TreeTransform<CurrentInstantiationRebuilder>(SemaRef),
6101 Loc(Loc), Entity(Entity) { }
6103 /// \brief Determine whether the given type \p T has already been
6106 /// For the purposes of type reconstruction, a type has already been
6107 /// transformed if it is NULL or if it is not dependent.
6108 bool AlreadyTransformed(QualType T) {
6109 return T.isNull() || !T->isDependentType();
6112 /// \brief Returns the location of the entity whose type is being
6114 SourceLocation getBaseLocation() { return Loc; }
6116 /// \brief Returns the name of the entity whose type is being rebuilt.
6117 DeclarationName getBaseEntity() { return Entity; }
6119 /// \brief Sets the "base" location and entity when that
6120 /// information is known based on another transformation.
6121 void setBase(SourceLocation Loc, DeclarationName Entity) {
6123 this->Entity = Entity;
6128 /// \brief Rebuilds a type within the context of the current instantiation.
6130 /// The type \p T is part of the type of an out-of-line member definition of
6131 /// a class template (or class template partial specialization) that was parsed
6132 /// and constructed before we entered the scope of the class template (or
6133 /// partial specialization thereof). This routine will rebuild that type now
6134 /// that we have entered the declarator's scope, which may produce different
6135 /// canonical types, e.g.,
6138 /// template<typename T>
6140 /// typedef T* pointer;
6144 /// template<typename T>
6145 /// typename X<T>::pointer X<T>::data() { ... }
6148 /// Here, the type "typename X<T>::pointer" will be created as a DependentNameType,
6149 /// since we do not know that we can look into X<T> when we parsed the type.
6150 /// This function will rebuild the type, performing the lookup of "pointer"
6151 /// in X<T> and returning an ElaboratedType whose canonical type is the same
6152 /// as the canonical type of T*, allowing the return types of the out-of-line
6153 /// definition and the declaration to match.
6154 TypeSourceInfo *Sema::RebuildTypeInCurrentInstantiation(TypeSourceInfo *T,
6156 DeclarationName Name) {
6157 if (!T || !T->getType()->isDependentType())
6160 CurrentInstantiationRebuilder Rebuilder(*this, Loc, Name);
6161 return Rebuilder.TransformType(T);
6164 ExprResult Sema::RebuildExprInCurrentInstantiation(Expr *E) {
6165 CurrentInstantiationRebuilder Rebuilder(*this, E->getExprLoc(),
6167 return Rebuilder.TransformExpr(E);
6170 bool Sema::RebuildNestedNameSpecifierInCurrentInstantiation(CXXScopeSpec &SS) {
6171 if (SS.isInvalid()) return true;
6173 NestedNameSpecifier *NNS = static_cast<NestedNameSpecifier*>(SS.getScopeRep());
6174 CurrentInstantiationRebuilder Rebuilder(*this, SS.getRange().getBegin(),
6176 NestedNameSpecifier *Rebuilt =
6177 Rebuilder.TransformNestedNameSpecifier(NNS, SS.getRange());
6178 if (!Rebuilt) return true;
6180 SS.setScopeRep(Rebuilt);
6184 /// \brief Produces a formatted string that describes the binding of
6185 /// template parameters to template arguments.
6187 Sema::getTemplateArgumentBindingsText(const TemplateParameterList *Params,
6188 const TemplateArgumentList &Args) {
6189 return getTemplateArgumentBindingsText(Params, Args.data(), Args.size());
6193 Sema::getTemplateArgumentBindingsText(const TemplateParameterList *Params,
6194 const TemplateArgument *Args,
6196 llvm::SmallString<128> Str;
6197 llvm::raw_svector_ostream Out(Str);
6199 if (!Params || Params->size() == 0 || NumArgs == 0)
6200 return std::string();
6202 for (unsigned I = 0, N = Params->size(); I != N; ++I) {
6211 if (const IdentifierInfo *Id = Params->getParam(I)->getIdentifier()) {
6212 Out << Id->getName();
6218 Args[I].print(Context.PrintingPolicy, Out);