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Diffstat (limited to 'contrib/llvm/tools/clang/lib/Sema/SemaTemplate.cpp')
| -rw-r--r-- | contrib/llvm/tools/clang/lib/Sema/SemaTemplate.cpp | 7188 |
1 files changed, 7188 insertions, 0 deletions
diff --git a/contrib/llvm/tools/clang/lib/Sema/SemaTemplate.cpp b/contrib/llvm/tools/clang/lib/Sema/SemaTemplate.cpp new file mode 100644 index 0000000..ff8c4da --- /dev/null +++ b/contrib/llvm/tools/clang/lib/Sema/SemaTemplate.cpp @@ -0,0 +1,7188 @@ +//===------- SemaTemplate.cpp - Semantic Analysis for C++ Templates -------===/ +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +//===----------------------------------------------------------------------===/ +// +// This file implements semantic analysis for C++ templates. +//===----------------------------------------------------------------------===/ + +#include "clang/Sema/SemaInternal.h" +#include "clang/Sema/Lookup.h" +#include "clang/Sema/Scope.h" +#include "clang/Sema/Template.h" +#include "clang/Sema/TemplateDeduction.h" +#include "TreeTransform.h" +#include "clang/AST/ASTContext.h" +#include "clang/AST/Expr.h" +#include "clang/AST/ExprCXX.h" +#include "clang/AST/DeclFriend.h" +#include "clang/AST/DeclTemplate.h" +#include "clang/AST/RecursiveASTVisitor.h" +#include "clang/AST/TypeVisitor.h" +#include "clang/Sema/DeclSpec.h" +#include "clang/Sema/ParsedTemplate.h" +#include "clang/Basic/LangOptions.h" +#include "clang/Basic/PartialDiagnostic.h" +#include "llvm/ADT/SmallBitVector.h" +#include "llvm/ADT/SmallString.h" +#include "llvm/ADT/StringExtras.h" +using namespace clang; +using namespace sema; + +// Exported for use by Parser. +SourceRange +clang::getTemplateParamsRange(TemplateParameterList const * const *Ps, + unsigned N) { + if (!N) return SourceRange(); + return SourceRange(Ps[0]->getTemplateLoc(), Ps[N-1]->getRAngleLoc()); +} + +/// \brief Determine whether the declaration found is acceptable as the name +/// of a template and, if so, return that template declaration. Otherwise, +/// returns NULL. +static NamedDecl *isAcceptableTemplateName(ASTContext &Context, + NamedDecl *Orig, + bool AllowFunctionTemplates) { + NamedDecl *D = Orig->getUnderlyingDecl(); + + if (isa<TemplateDecl>(D)) { + if (!AllowFunctionTemplates && isa<FunctionTemplateDecl>(D)) + return 0; + + return Orig; + } + + if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(D)) { + // C++ [temp.local]p1: + // Like normal (non-template) classes, class templates have an + // injected-class-name (Clause 9). The injected-class-name + // can be used with or without a template-argument-list. When + // it is used without a template-argument-list, it is + // equivalent to the injected-class-name followed by the + // template-parameters of the class template enclosed in + // <>. When it is used with a template-argument-list, it + // refers to the specified class template specialization, + // which could be the current specialization or another + // specialization. + if (Record->isInjectedClassName()) { + Record = cast<CXXRecordDecl>(Record->getDeclContext()); + if (Record->getDescribedClassTemplate()) + return Record->getDescribedClassTemplate(); + + if (ClassTemplateSpecializationDecl *Spec + = dyn_cast<ClassTemplateSpecializationDecl>(Record)) + return Spec->getSpecializedTemplate(); + } + + return 0; + } + + return 0; +} + +void Sema::FilterAcceptableTemplateNames(LookupResult &R, + bool AllowFunctionTemplates) { + // The set of class templates we've already seen. + llvm::SmallPtrSet<ClassTemplateDecl *, 8> ClassTemplates; + LookupResult::Filter filter = R.makeFilter(); + while (filter.hasNext()) { + NamedDecl *Orig = filter.next(); + NamedDecl *Repl = isAcceptableTemplateName(Context, Orig, + AllowFunctionTemplates); + if (!Repl) + filter.erase(); + else if (Repl != Orig) { + + // C++ [temp.local]p3: + // A lookup that finds an injected-class-name (10.2) can result in an + // ambiguity in certain cases (for example, if it is found in more than + // one base class). If all of the injected-class-names that are found + // refer to specializations of the same class template, and if the name + // is used as a template-name, the reference refers to the class + // template itself and not a specialization thereof, and is not + // ambiguous. + if (ClassTemplateDecl *ClassTmpl = dyn_cast<ClassTemplateDecl>(Repl)) + if (!ClassTemplates.insert(ClassTmpl)) { + filter.erase(); + continue; + } + + // FIXME: we promote access to public here as a workaround to + // the fact that LookupResult doesn't let us remember that we + // found this template through a particular injected class name, + // which means we end up doing nasty things to the invariants. + // Pretending that access is public is *much* safer. + filter.replace(Repl, AS_public); + } + } + filter.done(); +} + +bool Sema::hasAnyAcceptableTemplateNames(LookupResult &R, + bool AllowFunctionTemplates) { + for (LookupResult::iterator I = R.begin(), IEnd = R.end(); I != IEnd; ++I) + if (isAcceptableTemplateName(Context, *I, AllowFunctionTemplates)) + return true; + + return false; +} + +TemplateNameKind Sema::isTemplateName(Scope *S, + CXXScopeSpec &SS, + bool hasTemplateKeyword, + UnqualifiedId &Name, + ParsedType ObjectTypePtr, + bool EnteringContext, + TemplateTy &TemplateResult, + bool &MemberOfUnknownSpecialization) { + assert(getLangOpts().CPlusPlus && "No template names in C!"); + + DeclarationName TName; + MemberOfUnknownSpecialization = false; + + switch (Name.getKind()) { + case UnqualifiedId::IK_Identifier: + TName = DeclarationName(Name.Identifier); + break; + + case UnqualifiedId::IK_OperatorFunctionId: + TName = Context.DeclarationNames.getCXXOperatorName( + Name.OperatorFunctionId.Operator); + break; + + case UnqualifiedId::IK_LiteralOperatorId: + TName = Context.DeclarationNames.getCXXLiteralOperatorName(Name.Identifier); + break; + + default: + return TNK_Non_template; + } + + QualType ObjectType = ObjectTypePtr.get(); + + LookupResult R(*this, TName, Name.getLocStart(), LookupOrdinaryName); + LookupTemplateName(R, S, SS, ObjectType, EnteringContext, + MemberOfUnknownSpecialization); + if (R.empty()) return TNK_Non_template; + if (R.isAmbiguous()) { + // Suppress diagnostics; we'll redo this lookup later. + R.suppressDiagnostics(); + + // FIXME: we might have ambiguous templates, in which case we + // should at least parse them properly! + return TNK_Non_template; + } + + TemplateName Template; + TemplateNameKind TemplateKind; + + unsigned ResultCount = R.end() - R.begin(); + if (ResultCount > 1) { + // We assume that we'll preserve the qualifier from a function + // template name in other ways. + Template = Context.getOverloadedTemplateName(R.begin(), R.end()); + TemplateKind = TNK_Function_template; + + // We'll do this lookup again later. + R.suppressDiagnostics(); + } else { + TemplateDecl *TD = cast<TemplateDecl>((*R.begin())->getUnderlyingDecl()); + + if (SS.isSet() && !SS.isInvalid()) { + NestedNameSpecifier *Qualifier + = static_cast<NestedNameSpecifier *>(SS.getScopeRep()); + Template = Context.getQualifiedTemplateName(Qualifier, + hasTemplateKeyword, TD); + } else { + Template = TemplateName(TD); + } + + if (isa<FunctionTemplateDecl>(TD)) { + TemplateKind = TNK_Function_template; + + // We'll do this lookup again later. + R.suppressDiagnostics(); + } else { + assert(isa<ClassTemplateDecl>(TD) || isa<TemplateTemplateParmDecl>(TD) || + isa<TypeAliasTemplateDecl>(TD)); + TemplateKind = TNK_Type_template; + } + } + + TemplateResult = TemplateTy::make(Template); + return TemplateKind; +} + +bool Sema::DiagnoseUnknownTemplateName(const IdentifierInfo &II, + SourceLocation IILoc, + Scope *S, + const CXXScopeSpec *SS, + TemplateTy &SuggestedTemplate, + TemplateNameKind &SuggestedKind) { + // We can't recover unless there's a dependent scope specifier preceding the + // template name. + // FIXME: Typo correction? + if (!SS || !SS->isSet() || !isDependentScopeSpecifier(*SS) || + computeDeclContext(*SS)) + return false; + + // The code is missing a 'template' keyword prior to the dependent template + // name. + NestedNameSpecifier *Qualifier = (NestedNameSpecifier*)SS->getScopeRep(); + Diag(IILoc, diag::err_template_kw_missing) + << Qualifier << II.getName() + << FixItHint::CreateInsertion(IILoc, "template "); + SuggestedTemplate + = TemplateTy::make(Context.getDependentTemplateName(Qualifier, &II)); + SuggestedKind = TNK_Dependent_template_name; + return true; +} + +void Sema::LookupTemplateName(LookupResult &Found, + Scope *S, CXXScopeSpec &SS, + QualType ObjectType, + bool EnteringContext, + bool &MemberOfUnknownSpecialization) { + // Determine where to perform name lookup + MemberOfUnknownSpecialization = false; + DeclContext *LookupCtx = 0; + bool isDependent = false; + if (!ObjectType.isNull()) { + // This nested-name-specifier occurs in a member access expression, e.g., + // x->B::f, and we are looking into the type of the object. + assert(!SS.isSet() && "ObjectType and scope specifier cannot coexist"); + LookupCtx = computeDeclContext(ObjectType); + isDependent = ObjectType->isDependentType(); + assert((isDependent || !ObjectType->isIncompleteType()) && + "Caller should have completed object type"); + + // Template names cannot appear inside an Objective-C class or object type. + if (ObjectType->isObjCObjectOrInterfaceType()) { + Found.clear(); + return; + } + } else if (SS.isSet()) { + // This nested-name-specifier occurs after another nested-name-specifier, + // so long into the context associated with the prior nested-name-specifier. + LookupCtx = computeDeclContext(SS, EnteringContext); + isDependent = isDependentScopeSpecifier(SS); + + // The declaration context must be complete. + if (LookupCtx && RequireCompleteDeclContext(SS, LookupCtx)) + return; + } + + bool ObjectTypeSearchedInScope = false; + bool AllowFunctionTemplatesInLookup = true; + if (LookupCtx) { + // Perform "qualified" name lookup into the declaration context we + // computed, which is either the type of the base of a member access + // expression or the declaration context associated with a prior + // nested-name-specifier. + LookupQualifiedName(Found, LookupCtx); + if (!ObjectType.isNull() && Found.empty()) { + // C++ [basic.lookup.classref]p1: + // In a class member access expression (5.2.5), if the . or -> token is + // immediately followed by an identifier followed by a <, the + // identifier must be looked up to determine whether the < is the + // beginning of a template argument list (14.2) or a less-than operator. + // The identifier is first looked up in the class of the object + // expression. If the identifier is not found, it is then looked up in + // the context of the entire postfix-expression and shall name a class + // or function template. + if (S) LookupName(Found, S); + ObjectTypeSearchedInScope = true; + AllowFunctionTemplatesInLookup = false; + } + } else if (isDependent && (!S || ObjectType.isNull())) { + // We cannot look into a dependent object type or nested nme + // specifier. + MemberOfUnknownSpecialization = true; + return; + } else { + // Perform unqualified name lookup in the current scope. + LookupName(Found, S); + + if (!ObjectType.isNull()) + AllowFunctionTemplatesInLookup = false; + } + + if (Found.empty() && !isDependent) { + // If we did not find any names, attempt to correct any typos. + DeclarationName Name = Found.getLookupName(); + Found.clear(); + // Simple filter callback that, for keywords, only accepts the C++ *_cast + CorrectionCandidateCallback FilterCCC; + FilterCCC.WantTypeSpecifiers = false; + FilterCCC.WantExpressionKeywords = false; + FilterCCC.WantRemainingKeywords = false; + FilterCCC.WantCXXNamedCasts = true; + if (TypoCorrection Corrected = CorrectTypo(Found.getLookupNameInfo(), + Found.getLookupKind(), S, &SS, + FilterCCC, LookupCtx)) { + Found.setLookupName(Corrected.getCorrection()); + if (Corrected.getCorrectionDecl()) + Found.addDecl(Corrected.getCorrectionDecl()); + FilterAcceptableTemplateNames(Found); + if (!Found.empty()) { + std::string CorrectedStr(Corrected.getAsString(getLangOpts())); + std::string CorrectedQuotedStr(Corrected.getQuoted(getLangOpts())); + if (LookupCtx) + Diag(Found.getNameLoc(), diag::err_no_member_template_suggest) + << Name << LookupCtx << CorrectedQuotedStr << SS.getRange() + << FixItHint::CreateReplacement(Found.getNameLoc(), CorrectedStr); + else + Diag(Found.getNameLoc(), diag::err_no_template_suggest) + << Name << CorrectedQuotedStr + << FixItHint::CreateReplacement(Found.getNameLoc(), CorrectedStr); + if (TemplateDecl *Template = Found.getAsSingle<TemplateDecl>()) + Diag(Template->getLocation(), diag::note_previous_decl) + << CorrectedQuotedStr; + } + } else { + Found.setLookupName(Name); + } + } + + FilterAcceptableTemplateNames(Found, AllowFunctionTemplatesInLookup); + if (Found.empty()) { + if (isDependent) + MemberOfUnknownSpecialization = true; + return; + } + + if (S && !ObjectType.isNull() && !ObjectTypeSearchedInScope) { + // C++ [basic.lookup.classref]p1: + // [...] If the lookup in the class of the object expression finds a + // template, the name is also looked up in the context of the entire + // postfix-expression and [...] + // + LookupResult FoundOuter(*this, Found.getLookupName(), Found.getNameLoc(), + LookupOrdinaryName); + LookupName(FoundOuter, S); + FilterAcceptableTemplateNames(FoundOuter, /*AllowFunctionTemplates=*/false); + + if (FoundOuter.empty()) { + // - if the name is not found, the name found in the class of the + // object expression is used, otherwise + } else if (!FoundOuter.getAsSingle<ClassTemplateDecl>() || + FoundOuter.isAmbiguous()) { + // - if the name is found in the context of the entire + // postfix-expression and does not name a class template, the name + // found in the class of the object expression is used, otherwise + FoundOuter.clear(); + } else if (!Found.isSuppressingDiagnostics()) { + // - if the name found is a class template, it must refer to the same + // entity as the one found in the class of the object expression, + // otherwise the program is ill-formed. + if (!Found.isSingleResult() || + Found.getFoundDecl()->getCanonicalDecl() + != FoundOuter.getFoundDecl()->getCanonicalDecl()) { + Diag(Found.getNameLoc(), + diag::ext_nested_name_member_ref_lookup_ambiguous) + << Found.getLookupName() + << ObjectType; + Diag(Found.getRepresentativeDecl()->getLocation(), + diag::note_ambig_member_ref_object_type) + << ObjectType; + Diag(FoundOuter.getFoundDecl()->getLocation(), + diag::note_ambig_member_ref_scope); + + // Recover by taking the template that we found in the object + // expression's type. + } + } + } +} + +/// ActOnDependentIdExpression - Handle a dependent id-expression that +/// was just parsed. This is only possible with an explicit scope +/// specifier naming a dependent type. +ExprResult +Sema::ActOnDependentIdExpression(const CXXScopeSpec &SS, + SourceLocation TemplateKWLoc, + const DeclarationNameInfo &NameInfo, + bool isAddressOfOperand, + const TemplateArgumentListInfo *TemplateArgs) { + DeclContext *DC = getFunctionLevelDeclContext(); + + if (!isAddressOfOperand && + isa<CXXMethodDecl>(DC) && + cast<CXXMethodDecl>(DC)->isInstance()) { + QualType ThisType = cast<CXXMethodDecl>(DC)->getThisType(Context); + + // Since the 'this' expression is synthesized, we don't need to + // perform the double-lookup check. + NamedDecl *FirstQualifierInScope = 0; + + return Owned(CXXDependentScopeMemberExpr::Create(Context, + /*This*/ 0, ThisType, + /*IsArrow*/ true, + /*Op*/ SourceLocation(), + SS.getWithLocInContext(Context), + TemplateKWLoc, + FirstQualifierInScope, + NameInfo, + TemplateArgs)); + } + + return BuildDependentDeclRefExpr(SS, TemplateKWLoc, NameInfo, TemplateArgs); +} + +ExprResult +Sema::BuildDependentDeclRefExpr(const CXXScopeSpec &SS, + SourceLocation TemplateKWLoc, + const DeclarationNameInfo &NameInfo, + const TemplateArgumentListInfo *TemplateArgs) { + return Owned(DependentScopeDeclRefExpr::Create(Context, + SS.getWithLocInContext(Context), + TemplateKWLoc, + NameInfo, + TemplateArgs)); +} + +/// DiagnoseTemplateParameterShadow - Produce a diagnostic complaining +/// that the template parameter 'PrevDecl' is being shadowed by a new +/// declaration at location Loc. Returns true to indicate that this is +/// an error, and false otherwise. +void Sema::DiagnoseTemplateParameterShadow(SourceLocation Loc, Decl *PrevDecl) { + assert(PrevDecl->isTemplateParameter() && "Not a template parameter"); + + // Microsoft Visual C++ permits template parameters to be shadowed. + if (getLangOpts().MicrosoftExt) + return; + + // C++ [temp.local]p4: + // A template-parameter shall not be redeclared within its + // scope (including nested scopes). + Diag(Loc, diag::err_template_param_shadow) + << cast<NamedDecl>(PrevDecl)->getDeclName(); + Diag(PrevDecl->getLocation(), diag::note_template_param_here); + return; +} + +/// AdjustDeclIfTemplate - If the given decl happens to be a template, reset +/// the parameter D to reference the templated declaration and return a pointer +/// to the template declaration. Otherwise, do nothing to D and return null. +TemplateDecl *Sema::AdjustDeclIfTemplate(Decl *&D) { + if (TemplateDecl *Temp = dyn_cast_or_null<TemplateDecl>(D)) { + D = Temp->getTemplatedDecl(); + return Temp; + } + return 0; +} + +ParsedTemplateArgument ParsedTemplateArgument::getTemplatePackExpansion( + SourceLocation EllipsisLoc) const { + assert(Kind == Template && + "Only template template arguments can be pack expansions here"); + assert(getAsTemplate().get().containsUnexpandedParameterPack() && + "Template template argument pack expansion without packs"); + ParsedTemplateArgument Result(*this); + Result.EllipsisLoc = EllipsisLoc; + return Result; +} + +static TemplateArgumentLoc translateTemplateArgument(Sema &SemaRef, + const ParsedTemplateArgument &Arg) { + + switch (Arg.getKind()) { + case ParsedTemplateArgument::Type: { + TypeSourceInfo *DI; + QualType T = SemaRef.GetTypeFromParser(Arg.getAsType(), &DI); + if (!DI) + DI = SemaRef.Context.getTrivialTypeSourceInfo(T, Arg.getLocation()); + return TemplateArgumentLoc(TemplateArgument(T), DI); + } + + case ParsedTemplateArgument::NonType: { + Expr *E = static_cast<Expr *>(Arg.getAsExpr()); + return TemplateArgumentLoc(TemplateArgument(E), E); + } + + case ParsedTemplateArgument::Template: { + TemplateName Template = Arg.getAsTemplate().get(); + TemplateArgument TArg; + if (Arg.getEllipsisLoc().isValid()) + TArg = TemplateArgument(Template, llvm::Optional<unsigned int>()); + else + TArg = Template; + return TemplateArgumentLoc(TArg, + Arg.getScopeSpec().getWithLocInContext( + SemaRef.Context), + Arg.getLocation(), + Arg.getEllipsisLoc()); + } + } + + llvm_unreachable("Unhandled parsed template argument"); +} + +/// \brief Translates template arguments as provided by the parser +/// into template arguments used by semantic analysis. +void Sema::translateTemplateArguments(const ASTTemplateArgsPtr &TemplateArgsIn, + TemplateArgumentListInfo &TemplateArgs) { + for (unsigned I = 0, Last = TemplateArgsIn.size(); I != Last; ++I) + TemplateArgs.addArgument(translateTemplateArgument(*this, + TemplateArgsIn[I])); +} + +/// ActOnTypeParameter - Called when a C++ template type parameter +/// (e.g., "typename T") has been parsed. Typename specifies whether +/// the keyword "typename" was used to declare the type parameter +/// (otherwise, "class" was used), and KeyLoc is the location of the +/// "class" or "typename" keyword. ParamName is the name of the +/// parameter (NULL indicates an unnamed template parameter) and +/// ParamNameLoc is the location of the parameter name (if any). +/// If the type parameter has a default argument, it will be added +/// later via ActOnTypeParameterDefault. +Decl *Sema::ActOnTypeParameter(Scope *S, bool Typename, bool Ellipsis, + SourceLocation EllipsisLoc, + SourceLocation KeyLoc, + IdentifierInfo *ParamName, + SourceLocation ParamNameLoc, + unsigned Depth, unsigned Position, + SourceLocation EqualLoc, + ParsedType DefaultArg) { + assert(S->isTemplateParamScope() && + "Template type parameter not in template parameter scope!"); + bool Invalid = false; + + if (ParamName) { + NamedDecl *PrevDecl = LookupSingleName(S, ParamName, ParamNameLoc, + LookupOrdinaryName, + ForRedeclaration); + if (PrevDecl && PrevDecl->isTemplateParameter()) { + DiagnoseTemplateParameterShadow(ParamNameLoc, PrevDecl); + PrevDecl = 0; + } + } + + SourceLocation Loc = ParamNameLoc; + if (!ParamName) + Loc = KeyLoc; + + TemplateTypeParmDecl *Param + = TemplateTypeParmDecl::Create(Context, Context.getTranslationUnitDecl(), + KeyLoc, Loc, Depth, Position, ParamName, + Typename, Ellipsis); + Param->setAccess(AS_public); + if (Invalid) + Param->setInvalidDecl(); + + if (ParamName) { + // Add the template parameter into the current scope. + S->AddDecl(Param); + IdResolver.AddDecl(Param); + } + + // C++0x [temp.param]p9: + // A default template-argument may be specified for any kind of + // template-parameter that is not a template parameter pack. + if (DefaultArg && Ellipsis) { + Diag(EqualLoc, diag::err_template_param_pack_default_arg); + DefaultArg = ParsedType(); + } + + // Handle the default argument, if provided. + if (DefaultArg) { + TypeSourceInfo *DefaultTInfo; + GetTypeFromParser(DefaultArg, &DefaultTInfo); + + assert(DefaultTInfo && "expected source information for type"); + + // Check for unexpanded parameter packs. + if (DiagnoseUnexpandedParameterPack(Loc, DefaultTInfo, + UPPC_DefaultArgument)) + return Param; + + // Check the template argument itself. + if (CheckTemplateArgument(Param, DefaultTInfo)) { + Param->setInvalidDecl(); + return Param; + } + + Param->setDefaultArgument(DefaultTInfo, false); + } + + return Param; +} + +/// \brief Check that the type of a non-type template parameter is +/// well-formed. +/// +/// \returns the (possibly-promoted) parameter type if valid; +/// otherwise, produces a diagnostic and returns a NULL type. +QualType +Sema::CheckNonTypeTemplateParameterType(QualType T, SourceLocation Loc) { + // We don't allow variably-modified types as the type of non-type template + // parameters. + if (T->isVariablyModifiedType()) { + Diag(Loc, diag::err_variably_modified_nontype_template_param) + << T; + return QualType(); + } + + // C++ [temp.param]p4: + // + // A non-type template-parameter shall have one of the following + // (optionally cv-qualified) types: + // + // -- integral or enumeration type, + if (T->isIntegralOrEnumerationType() || + // -- pointer to object or pointer to function, + T->isPointerType() || + // -- reference to object or reference to function, + T->isReferenceType() || + // -- pointer to member, + T->isMemberPointerType() || + // -- std::nullptr_t. + T->isNullPtrType() || + // If T is a dependent type, we can't do the check now, so we + // assume that it is well-formed. + T->isDependentType()) { + // C++ [temp.param]p5: The top-level cv-qualifiers on the template-parameter + // are ignored when determining its type. + return T.getUnqualifiedType(); + } + + // C++ [temp.param]p8: + // + // A non-type template-parameter of type "array of T" or + // "function returning T" is adjusted to be of type "pointer to + // T" or "pointer to function returning T", respectively. + else if (T->isArrayType()) + // FIXME: Keep the type prior to promotion? + return Context.getArrayDecayedType(T); + else if (T->isFunctionType()) + // FIXME: Keep the type prior to promotion? + return Context.getPointerType(T); + + Diag(Loc, diag::err_template_nontype_parm_bad_type) + << T; + + return QualType(); +} + +Decl *Sema::ActOnNonTypeTemplateParameter(Scope *S, Declarator &D, + unsigned Depth, + unsigned Position, + SourceLocation EqualLoc, + Expr *Default) { + TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); + QualType T = TInfo->getType(); + + assert(S->isTemplateParamScope() && + "Non-type template parameter not in template parameter scope!"); + bool Invalid = false; + + IdentifierInfo *ParamName = D.getIdentifier(); + if (ParamName) { + NamedDecl *PrevDecl = LookupSingleName(S, ParamName, D.getIdentifierLoc(), + LookupOrdinaryName, + ForRedeclaration); + if (PrevDecl && PrevDecl->isTemplateParameter()) { + DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); + PrevDecl = 0; + } + } + + T = CheckNonTypeTemplateParameterType(T, D.getIdentifierLoc()); + if (T.isNull()) { + T = Context.IntTy; // Recover with an 'int' type. + Invalid = true; + } + + bool IsParameterPack = D.hasEllipsis(); + NonTypeTemplateParmDecl *Param + = NonTypeTemplateParmDecl::Create(Context, Context.getTranslationUnitDecl(), + D.getLocStart(), + D.getIdentifierLoc(), + Depth, Position, ParamName, T, + IsParameterPack, TInfo); + Param->setAccess(AS_public); + + if (Invalid) + Param->setInvalidDecl(); + + if (D.getIdentifier()) { + // Add the template parameter into the current scope. + S->AddDecl(Param); + IdResolver.AddDecl(Param); + } + + // C++0x [temp.param]p9: + // A default template-argument may be specified for any kind of + // template-parameter that is not a template parameter pack. + if (Default && IsParameterPack) { + Diag(EqualLoc, diag::err_template_param_pack_default_arg); + Default = 0; + } + + // Check the well-formedness of the default template argument, if provided. + if (Default) { + // Check for unexpanded parameter packs. + if (DiagnoseUnexpandedParameterPack(Default, UPPC_DefaultArgument)) + return Param; + + TemplateArgument Converted; + ExprResult DefaultRes = CheckTemplateArgument(Param, Param->getType(), Default, Converted); + if (DefaultRes.isInvalid()) { + Param->setInvalidDecl(); + return Param; + } + Default = DefaultRes.take(); + + Param->setDefaultArgument(Default, false); + } + + return Param; +} + +/// ActOnTemplateTemplateParameter - Called when a C++ template template +/// parameter (e.g. T in template <template <typename> class T> class array) +/// has been parsed. S is the current scope. +Decl *Sema::ActOnTemplateTemplateParameter(Scope* S, + SourceLocation TmpLoc, + TemplateParameterList *Params, + SourceLocation EllipsisLoc, + IdentifierInfo *Name, + SourceLocation NameLoc, + unsigned Depth, + unsigned Position, + SourceLocation EqualLoc, + ParsedTemplateArgument Default) { + assert(S->isTemplateParamScope() && + "Template template parameter not in template parameter scope!"); + + // Construct the parameter object. + bool IsParameterPack = EllipsisLoc.isValid(); + TemplateTemplateParmDecl *Param = + TemplateTemplateParmDecl::Create(Context, Context.getTranslationUnitDecl(), + NameLoc.isInvalid()? TmpLoc : NameLoc, + Depth, Position, IsParameterPack, + Name, Params); + Param->setAccess(AS_public); + + // If the template template parameter has a name, then link the identifier + // into the scope and lookup mechanisms. + if (Name) { + S->AddDecl(Param); + IdResolver.AddDecl(Param); + } + + if (Params->size() == 0) { + Diag(Param->getLocation(), diag::err_template_template_parm_no_parms) + << SourceRange(Params->getLAngleLoc(), Params->getRAngleLoc()); + Param->setInvalidDecl(); + } + + // C++0x [temp.param]p9: + // A default template-argument may be specified for any kind of + // template-parameter that is not a template parameter pack. + if (IsParameterPack && !Default.isInvalid()) { + Diag(EqualLoc, diag::err_template_param_pack_default_arg); + Default = ParsedTemplateArgument(); + } + + if (!Default.isInvalid()) { + // Check only that we have a template template argument. We don't want to + // try to check well-formedness now, because our template template parameter + // might have dependent types in its template parameters, which we wouldn't + // be able to match now. + // + // If none of the template template parameter's template arguments mention + // other template parameters, we could actually perform more checking here. + // However, it isn't worth doing. + TemplateArgumentLoc DefaultArg = translateTemplateArgument(*this, Default); + if (DefaultArg.getArgument().getAsTemplate().isNull()) { + Diag(DefaultArg.getLocation(), diag::err_template_arg_not_class_template) + << DefaultArg.getSourceRange(); + return Param; + } + + // Check for unexpanded parameter packs. + if (DiagnoseUnexpandedParameterPack(DefaultArg.getLocation(), + DefaultArg.getArgument().getAsTemplate(), + UPPC_DefaultArgument)) + return Param; + + Param->setDefaultArgument(DefaultArg, false); + } + + return Param; +} + +/// ActOnTemplateParameterList - Builds a TemplateParameterList that +/// contains the template parameters in Params/NumParams. +TemplateParameterList * +Sema::ActOnTemplateParameterList(unsigned Depth, + SourceLocation ExportLoc, + SourceLocation TemplateLoc, + SourceLocation LAngleLoc, + Decl **Params, unsigned NumParams, + SourceLocation RAngleLoc) { + if (ExportLoc.isValid()) + Diag(ExportLoc, diag::warn_template_export_unsupported); + + return TemplateParameterList::Create(Context, TemplateLoc, LAngleLoc, + (NamedDecl**)Params, NumParams, + RAngleLoc); +} + +static void SetNestedNameSpecifier(TagDecl *T, const CXXScopeSpec &SS) { + if (SS.isSet()) + T->setQualifierInfo(SS.getWithLocInContext(T->getASTContext())); +} + +DeclResult +Sema::CheckClassTemplate(Scope *S, unsigned TagSpec, TagUseKind TUK, + SourceLocation KWLoc, CXXScopeSpec &SS, + IdentifierInfo *Name, SourceLocation NameLoc, + AttributeList *Attr, + TemplateParameterList *TemplateParams, + AccessSpecifier AS, SourceLocation ModulePrivateLoc, + unsigned NumOuterTemplateParamLists, + TemplateParameterList** OuterTemplateParamLists) { + assert(TemplateParams && TemplateParams->size() > 0 && + "No template parameters"); + assert(TUK != TUK_Reference && "Can only declare or define class templates"); + bool Invalid = false; + + // Check that we can declare a template here. + if (CheckTemplateDeclScope(S, TemplateParams)) + return true; + + TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec); + assert(Kind != TTK_Enum && "can't build template of enumerated type"); + + // There is no such thing as an unnamed class template. + if (!Name) { + Diag(KWLoc, diag::err_template_unnamed_class); + return true; + } + + // Find any previous declaration with this name. + DeclContext *SemanticContext; + LookupResult Previous(*this, Name, NameLoc, LookupOrdinaryName, + ForRedeclaration); + if (SS.isNotEmpty() && !SS.isInvalid()) { + SemanticContext = computeDeclContext(SS, true); + if (!SemanticContext) { + // FIXME: Horrible, horrible hack! We can't currently represent this + // in the AST, and historically we have just ignored such friend + // class templates, so don't complain here. + if (TUK != TUK_Friend) + Diag(NameLoc, diag::err_template_qualified_declarator_no_match) + << SS.getScopeRep() << SS.getRange(); + return true; + } + + if (RequireCompleteDeclContext(SS, SemanticContext)) + return true; + + // If we're adding a template to a dependent context, we may need to + // rebuilding some of the types used within the template parameter list, + // now that we know what the current instantiation is. + if (SemanticContext->isDependentContext()) { + ContextRAII SavedContext(*this, SemanticContext); + if (RebuildTemplateParamsInCurrentInstantiation(TemplateParams)) + Invalid = true; + } else if (TUK != TUK_Friend && TUK != TUK_Reference) + diagnoseQualifiedDeclaration(SS, SemanticContext, Name, NameLoc); + + LookupQualifiedName(Previous, SemanticContext); + } else { + SemanticContext = CurContext; + LookupName(Previous, S); + } + + if (Previous.isAmbiguous()) + return true; + + NamedDecl *PrevDecl = 0; + if (Previous.begin() != Previous.end()) + PrevDecl = (*Previous.begin())->getUnderlyingDecl(); + + // If there is a previous declaration with the same name, check + // whether this is a valid redeclaration. + ClassTemplateDecl *PrevClassTemplate + = dyn_cast_or_null<ClassTemplateDecl>(PrevDecl); + + // We may have found the injected-class-name of a class template, + // class template partial specialization, or class template specialization. + // In these cases, grab the template that is being defined or specialized. + if (!PrevClassTemplate && PrevDecl && isa<CXXRecordDecl>(PrevDecl) && + cast<CXXRecordDecl>(PrevDecl)->isInjectedClassName()) { + PrevDecl = cast<CXXRecordDecl>(PrevDecl->getDeclContext()); + PrevClassTemplate + = cast<CXXRecordDecl>(PrevDecl)->getDescribedClassTemplate(); + if (!PrevClassTemplate && isa<ClassTemplateSpecializationDecl>(PrevDecl)) { + PrevClassTemplate + = cast<ClassTemplateSpecializationDecl>(PrevDecl) + ->getSpecializedTemplate(); + } + } + + if (TUK == TUK_Friend) { + // C++ [namespace.memdef]p3: + // [...] When looking for a prior declaration of a class or a function + // declared as a friend, and when the name of the friend class or + // function is neither a qualified name nor a template-id, scopes outside + // the innermost enclosing namespace scope are not considered. + if (!SS.isSet()) { + DeclContext *OutermostContext = CurContext; + while (!OutermostContext->isFileContext()) + OutermostContext = OutermostContext->getLookupParent(); + + if (PrevDecl && + (OutermostContext->Equals(PrevDecl->getDeclContext()) || + OutermostContext->Encloses(PrevDecl->getDeclContext()))) { + SemanticContext = PrevDecl->getDeclContext(); + } else { + // Declarations in outer scopes don't matter. However, the outermost + // context we computed is the semantic context for our new + // declaration. + PrevDecl = PrevClassTemplate = 0; + SemanticContext = OutermostContext; + } + } + + if (CurContext->isDependentContext()) { + // If this is a dependent context, we don't want to link the friend + // class template to the template in scope, because that would perform + // checking of the template parameter lists that can't be performed + // until the outer context is instantiated. + PrevDecl = PrevClassTemplate = 0; + } + } else if (PrevDecl && !isDeclInScope(PrevDecl, SemanticContext, S)) + PrevDecl = PrevClassTemplate = 0; + + if (PrevClassTemplate) { + // Ensure that the template parameter lists are compatible. + if (!TemplateParameterListsAreEqual(TemplateParams, + PrevClassTemplate->getTemplateParameters(), + /*Complain=*/true, + TPL_TemplateMatch)) + return true; + + // C++ [temp.class]p4: + // In a redeclaration, partial specialization, explicit + // specialization or explicit instantiation of a class template, + // the class-key shall agree in kind with the original class + // template declaration (7.1.5.3). + RecordDecl *PrevRecordDecl = PrevClassTemplate->getTemplatedDecl(); + if (!isAcceptableTagRedeclaration(PrevRecordDecl, Kind, + TUK == TUK_Definition, KWLoc, *Name)) { + Diag(KWLoc, diag::err_use_with_wrong_tag) + << Name + << FixItHint::CreateReplacement(KWLoc, PrevRecordDecl->getKindName()); + Diag(PrevRecordDecl->getLocation(), diag::note_previous_use); + Kind = PrevRecordDecl->getTagKind(); + } + + // Check for redefinition of this class template. + if (TUK == TUK_Definition) { + if (TagDecl *Def = PrevRecordDecl->getDefinition()) { + Diag(NameLoc, diag::err_redefinition) << Name; + Diag(Def->getLocation(), diag::note_previous_definition); + // FIXME: Would it make sense to try to "forget" the previous + // definition, as part of error recovery? + return true; + } + } + } else if (PrevDecl && PrevDecl->isTemplateParameter()) { + // Maybe we will complain about the shadowed template parameter. + DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); + // Just pretend that we didn't see the previous declaration. + PrevDecl = 0; + } else if (PrevDecl) { + // C++ [temp]p5: + // A class template shall not have the same name as any other + // template, class, function, object, enumeration, enumerator, + // namespace, or type in the same scope (3.3), except as specified + // in (14.5.4). + Diag(NameLoc, diag::err_redefinition_different_kind) << Name; + Diag(PrevDecl->getLocation(), diag::note_previous_definition); + return true; + } + + // Check the template parameter list of this declaration, possibly + // merging in the template parameter list from the previous class + // template declaration. + if (CheckTemplateParameterList(TemplateParams, + PrevClassTemplate? PrevClassTemplate->getTemplateParameters() : 0, + (SS.isSet() && SemanticContext && + SemanticContext->isRecord() && + SemanticContext->isDependentContext()) + ? TPC_ClassTemplateMember + : TPC_ClassTemplate)) + Invalid = true; + + if (SS.isSet()) { + // If the name of the template was qualified, we must be defining the + // template out-of-line. + if (!SS.isInvalid() && !Invalid && !PrevClassTemplate && + !(TUK == TUK_Friend && CurContext->isDependentContext())) { + Diag(NameLoc, diag::err_member_def_does_not_match) + << Name << SemanticContext << SS.getRange(); + Invalid = true; + } + } + + CXXRecordDecl *NewClass = + CXXRecordDecl::Create(Context, Kind, SemanticContext, KWLoc, NameLoc, Name, + PrevClassTemplate? + PrevClassTemplate->getTemplatedDecl() : 0, + /*DelayTypeCreation=*/true); + SetNestedNameSpecifier(NewClass, SS); + if (NumOuterTemplateParamLists > 0) + NewClass->setTemplateParameterListsInfo(Context, + NumOuterTemplateParamLists, + OuterTemplateParamLists); + + // Add alignment attributes if necessary; these attributes are checked when + // the ASTContext lays out the structure. + AddAlignmentAttributesForRecord(NewClass); + AddMsStructLayoutForRecord(NewClass); + + ClassTemplateDecl *NewTemplate + = ClassTemplateDecl::Create(Context, SemanticContext, NameLoc, + DeclarationName(Name), TemplateParams, + NewClass, PrevClassTemplate); + NewClass->setDescribedClassTemplate(NewTemplate); + + if (ModulePrivateLoc.isValid()) + NewTemplate->setModulePrivate(); + + // Build the type for the class template declaration now. + QualType T = NewTemplate->getInjectedClassNameSpecialization(); + T = Context.getInjectedClassNameType(NewClass, T); + assert(T->isDependentType() && "Class template type is not dependent?"); + (void)T; + + // If we are providing an explicit specialization of a member that is a + // class template, make a note of that. + if (PrevClassTemplate && + PrevClassTemplate->getInstantiatedFromMemberTemplate()) + PrevClassTemplate->setMemberSpecialization(); + + // Set the access specifier. + if (!Invalid && TUK != TUK_Friend && NewTemplate->getDeclContext()->isRecord()) + SetMemberAccessSpecifier(NewTemplate, PrevClassTemplate, AS); + + // Set the lexical context of these templates + NewClass->setLexicalDeclContext(CurContext); + NewTemplate->setLexicalDeclContext(CurContext); + + if (TUK == TUK_Definition) + NewClass->startDefinition(); + + if (Attr) + ProcessDeclAttributeList(S, NewClass, Attr); + + if (TUK != TUK_Friend) + PushOnScopeChains(NewTemplate, S); + else { + if (PrevClassTemplate && PrevClassTemplate->getAccess() != AS_none) { + NewTemplate->setAccess(PrevClassTemplate->getAccess()); + NewClass->setAccess(PrevClassTemplate->getAccess()); + } + + NewTemplate->setObjectOfFriendDecl(/* PreviouslyDeclared = */ + PrevClassTemplate != NULL); + + // Friend templates are visible in fairly strange ways. + if (!CurContext->isDependentContext()) { + DeclContext *DC = SemanticContext->getRedeclContext(); + DC->makeDeclVisibleInContext(NewTemplate); + if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) + PushOnScopeChains(NewTemplate, EnclosingScope, + /* AddToContext = */ false); + } + + FriendDecl *Friend = FriendDecl::Create(Context, CurContext, + NewClass->getLocation(), + NewTemplate, + /*FIXME:*/NewClass->getLocation()); + Friend->setAccess(AS_public); + CurContext->addDecl(Friend); + } + + if (Invalid) { + NewTemplate->setInvalidDecl(); + NewClass->setInvalidDecl(); + } + return NewTemplate; +} + +/// \brief Diagnose the presence of a default template argument on a +/// template parameter, which is ill-formed in certain contexts. +/// +/// \returns true if the default template argument should be dropped. +static bool DiagnoseDefaultTemplateArgument(Sema &S, + Sema::TemplateParamListContext TPC, + SourceLocation ParamLoc, + SourceRange DefArgRange) { + switch (TPC) { + case Sema::TPC_ClassTemplate: + case Sema::TPC_TypeAliasTemplate: + return false; + + case Sema::TPC_FunctionTemplate: + case Sema::TPC_FriendFunctionTemplateDefinition: + // C++ [temp.param]p9: + // A default template-argument shall not be specified in a + // function template declaration or a function template + // definition [...] + // If a friend function template declaration specifies a default + // template-argument, that declaration shall be a definition and shall be + // the only declaration of the function template in the translation unit. + // (C++98/03 doesn't have this wording; see DR226). + S.Diag(ParamLoc, S.getLangOpts().CPlusPlus0x ? + diag::warn_cxx98_compat_template_parameter_default_in_function_template + : diag::ext_template_parameter_default_in_function_template) + << DefArgRange; + return false; + + case Sema::TPC_ClassTemplateMember: + // C++0x [temp.param]p9: + // A default template-argument shall not be specified in the + // template-parameter-lists of the definition of a member of a + // class template that appears outside of the member's class. + S.Diag(ParamLoc, diag::err_template_parameter_default_template_member) + << DefArgRange; + return true; + + case Sema::TPC_FriendFunctionTemplate: + // C++ [temp.param]p9: + // A default template-argument shall not be specified in a + // friend template declaration. + S.Diag(ParamLoc, diag::err_template_parameter_default_friend_template) + << DefArgRange; + return true; + + // FIXME: C++0x [temp.param]p9 allows default template-arguments + // for friend function templates if there is only a single + // declaration (and it is a definition). Strange! + } + + llvm_unreachable("Invalid TemplateParamListContext!"); +} + +/// \brief Check for unexpanded parameter packs within the template parameters +/// of a template template parameter, recursively. +static bool DiagnoseUnexpandedParameterPacks(Sema &S, + TemplateTemplateParmDecl *TTP) { + TemplateParameterList *Params = TTP->getTemplateParameters(); + for (unsigned I = 0, N = Params->size(); I != N; ++I) { + NamedDecl *P = Params->getParam(I); + if (NonTypeTemplateParmDecl *NTTP = dyn_cast<NonTypeTemplateParmDecl>(P)) { + if (S.DiagnoseUnexpandedParameterPack(NTTP->getLocation(), + NTTP->getTypeSourceInfo(), + Sema::UPPC_NonTypeTemplateParameterType)) + return true; + + continue; + } + + if (TemplateTemplateParmDecl *InnerTTP + = dyn_cast<TemplateTemplateParmDecl>(P)) + if (DiagnoseUnexpandedParameterPacks(S, InnerTTP)) + return true; + } + + return false; +} + +/// \brief Checks the validity of a template parameter list, possibly +/// considering the template parameter list from a previous +/// declaration. +/// +/// If an "old" template parameter list is provided, it must be +/// equivalent (per TemplateParameterListsAreEqual) to the "new" +/// template parameter list. +/// +/// \param NewParams Template parameter list for a new template +/// declaration. This template parameter list will be updated with any +/// default arguments that are carried through from the previous +/// template parameter list. +/// +/// \param OldParams If provided, template parameter list from a +/// previous declaration of the same template. Default template +/// arguments will be merged from the old template parameter list to +/// the new template parameter list. +/// +/// \param TPC Describes the context in which we are checking the given +/// template parameter list. +/// +/// \returns true if an error occurred, false otherwise. +bool Sema::CheckTemplateParameterList(TemplateParameterList *NewParams, + TemplateParameterList *OldParams, + TemplateParamListContext TPC) { + bool Invalid = false; + + // C++ [temp.param]p10: + // The set of default template-arguments available for use with a + // template declaration or definition is obtained by merging the + // default arguments from the definition (if in scope) and all + // declarations in scope in the same way default function + // arguments are (8.3.6). + bool SawDefaultArgument = false; + SourceLocation PreviousDefaultArgLoc; + + // Dummy initialization to avoid warnings. + TemplateParameterList::iterator OldParam = NewParams->end(); + if (OldParams) + OldParam = OldParams->begin(); + + bool RemoveDefaultArguments = false; + for (TemplateParameterList::iterator NewParam = NewParams->begin(), + NewParamEnd = NewParams->end(); + NewParam != NewParamEnd; ++NewParam) { + // Variables used to diagnose redundant default arguments + bool RedundantDefaultArg = false; + SourceLocation OldDefaultLoc; + SourceLocation NewDefaultLoc; + + // Variable used to diagnose missing default arguments + bool MissingDefaultArg = false; + + // Variable used to diagnose non-final parameter packs + bool SawParameterPack = false; + + if (TemplateTypeParmDecl *NewTypeParm + = dyn_cast<TemplateTypeParmDecl>(*NewParam)) { + // Check the presence of a default argument here. + if (NewTypeParm->hasDefaultArgument() && + DiagnoseDefaultTemplateArgument(*this, TPC, + NewTypeParm->getLocation(), + NewTypeParm->getDefaultArgumentInfo()->getTypeLoc() + .getSourceRange())) + NewTypeParm->removeDefaultArgument(); + + // Merge default arguments for template type parameters. + TemplateTypeParmDecl *OldTypeParm + = OldParams? cast<TemplateTypeParmDecl>(*OldParam) : 0; + + if (NewTypeParm->isParameterPack()) { + assert(!NewTypeParm->hasDefaultArgument() && + "Parameter packs can't have a default argument!"); + SawParameterPack = true; + } else if (OldTypeParm && OldTypeParm->hasDefaultArgument() && + NewTypeParm->hasDefaultArgument()) { + OldDefaultLoc = OldTypeParm->getDefaultArgumentLoc(); + NewDefaultLoc = NewTypeParm->getDefaultArgumentLoc(); + SawDefaultArgument = true; + RedundantDefaultArg = true; + PreviousDefaultArgLoc = NewDefaultLoc; + } else if (OldTypeParm && OldTypeParm->hasDefaultArgument()) { + // Merge the default argument from the old declaration to the + // new declaration. + SawDefaultArgument = true; + NewTypeParm->setDefaultArgument(OldTypeParm->getDefaultArgumentInfo(), + true); + PreviousDefaultArgLoc = OldTypeParm->getDefaultArgumentLoc(); + } else if (NewTypeParm->hasDefaultArgument()) { + SawDefaultArgument = true; + PreviousDefaultArgLoc = NewTypeParm->getDefaultArgumentLoc(); + } else if (SawDefaultArgument) + MissingDefaultArg = true; + } else if (NonTypeTemplateParmDecl *NewNonTypeParm + = dyn_cast<NonTypeTemplateParmDecl>(*NewParam)) { + // Check for unexpanded parameter packs. + if (DiagnoseUnexpandedParameterPack(NewNonTypeParm->getLocation(), + NewNonTypeParm->getTypeSourceInfo(), + UPPC_NonTypeTemplateParameterType)) { + Invalid = true; + continue; + } + + // Check the presence of a default argument here. + if (NewNonTypeParm->hasDefaultArgument() && + DiagnoseDefaultTemplateArgument(*this, TPC, + NewNonTypeParm->getLocation(), + NewNonTypeParm->getDefaultArgument()->getSourceRange())) { + NewNonTypeParm->removeDefaultArgument(); + } + + // Merge default arguments for non-type template parameters + NonTypeTemplateParmDecl *OldNonTypeParm + = OldParams? cast<NonTypeTemplateParmDecl>(*OldParam) : 0; + if (NewNonTypeParm->isParameterPack()) { + assert(!NewNonTypeParm->hasDefaultArgument() && + "Parameter packs can't have a default argument!"); + SawParameterPack = true; + } else if (OldNonTypeParm && OldNonTypeParm->hasDefaultArgument() && + NewNonTypeParm->hasDefaultArgument()) { + OldDefaultLoc = OldNonTypeParm->getDefaultArgumentLoc(); + NewDefaultLoc = NewNonTypeParm->getDefaultArgumentLoc(); + SawDefaultArgument = true; + RedundantDefaultArg = true; + PreviousDefaultArgLoc = NewDefaultLoc; + } else if (OldNonTypeParm && OldNonTypeParm->hasDefaultArgument()) { + // Merge the default argument from the old declaration to the + // new declaration. + SawDefaultArgument = true; + // FIXME: We need to create a new kind of "default argument" + // expression that points to a previous non-type template + // parameter. + NewNonTypeParm->setDefaultArgument( + OldNonTypeParm->getDefaultArgument(), + /*Inherited=*/ true); + PreviousDefaultArgLoc = OldNonTypeParm->getDefaultArgumentLoc(); + } else if (NewNonTypeParm->hasDefaultArgument()) { + SawDefaultArgument = true; + PreviousDefaultArgLoc = NewNonTypeParm->getDefaultArgumentLoc(); + } else if (SawDefaultArgument) + MissingDefaultArg = true; + } else { + TemplateTemplateParmDecl *NewTemplateParm + = cast<TemplateTemplateParmDecl>(*NewParam); + + // Check for unexpanded parameter packs, recursively. + if (::DiagnoseUnexpandedParameterPacks(*this, NewTemplateParm)) { + Invalid = true; + continue; + } + + // Check the presence of a default argument here. + if (NewTemplateParm->hasDefaultArgument() && + DiagnoseDefaultTemplateArgument(*this, TPC, + NewTemplateParm->getLocation(), + NewTemplateParm->getDefaultArgument().getSourceRange())) + NewTemplateParm->removeDefaultArgument(); + + // Merge default arguments for template template parameters + TemplateTemplateParmDecl *OldTemplateParm + = OldParams? cast<TemplateTemplateParmDecl>(*OldParam) : 0; + if (NewTemplateParm->isParameterPack()) { + assert(!NewTemplateParm->hasDefaultArgument() && + "Parameter packs can't have a default argument!"); + SawParameterPack = true; + } else if (OldTemplateParm && OldTemplateParm->hasDefaultArgument() && + NewTemplateParm->hasDefaultArgument()) { + OldDefaultLoc = OldTemplateParm->getDefaultArgument().getLocation(); + NewDefaultLoc = NewTemplateParm->getDefaultArgument().getLocation(); + SawDefaultArgument = true; + RedundantDefaultArg = true; + PreviousDefaultArgLoc = NewDefaultLoc; + } else if (OldTemplateParm && OldTemplateParm->hasDefaultArgument()) { + // Merge the default argument from the old declaration to the + // new declaration. + SawDefaultArgument = true; + // FIXME: We need to create a new kind of "default argument" expression + // that points to a previous template template parameter. + NewTemplateParm->setDefaultArgument( + OldTemplateParm->getDefaultArgument(), + /*Inherited=*/ true); + PreviousDefaultArgLoc + = OldTemplateParm->getDefaultArgument().getLocation(); + } else if (NewTemplateParm->hasDefaultArgument()) { + SawDefaultArgument = true; + PreviousDefaultArgLoc + = NewTemplateParm->getDefaultArgument().getLocation(); + } else if (SawDefaultArgument) + MissingDefaultArg = true; + } + + // C++0x [temp.param]p11: + // If a template parameter of a primary class template or alias template + // is a template parameter pack, it shall be the last template parameter. + if (SawParameterPack && (NewParam + 1) != NewParamEnd && + (TPC == TPC_ClassTemplate || TPC == TPC_TypeAliasTemplate)) { + Diag((*NewParam)->getLocation(), + diag::err_template_param_pack_must_be_last_template_parameter); + Invalid = true; + } + + if (RedundantDefaultArg) { + // C++ [temp.param]p12: + // A template-parameter shall not be given default arguments + // by two different declarations in the same scope. + Diag(NewDefaultLoc, diag::err_template_param_default_arg_redefinition); + Diag(OldDefaultLoc, diag::note_template_param_prev_default_arg); + Invalid = true; + } else if (MissingDefaultArg && TPC != TPC_FunctionTemplate) { + // C++ [temp.param]p11: + // If a template-parameter of a class template has a default + // template-argument, each subsequent template-parameter shall either + // have a default template-argument supplied or be a template parameter + // pack. + Diag((*NewParam)->getLocation(), + diag::err_template_param_default_arg_missing); + Diag(PreviousDefaultArgLoc, diag::note_template_param_prev_default_arg); + Invalid = true; + RemoveDefaultArguments = true; + } + + // If we have an old template parameter list that we're merging + // in, move on to the next parameter. + if (OldParams) + ++OldParam; + } + + // We were missing some default arguments at the end of the list, so remove + // all of the default arguments. + if (RemoveDefaultArguments) { + for (TemplateParameterList::iterator NewParam = NewParams->begin(), + NewParamEnd = NewParams->end(); + NewParam != NewParamEnd; ++NewParam) { + if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(*NewParam)) + TTP->removeDefaultArgument(); + else if (NonTypeTemplateParmDecl *NTTP + = dyn_cast<NonTypeTemplateParmDecl>(*NewParam)) + NTTP->removeDefaultArgument(); + else + cast<TemplateTemplateParmDecl>(*NewParam)->removeDefaultArgument(); + } + } + + return Invalid; +} + +namespace { + +/// A class which looks for a use of a certain level of template +/// parameter. +struct DependencyChecker : RecursiveASTVisitor<DependencyChecker> { + typedef RecursiveASTVisitor<DependencyChecker> super; + + unsigned Depth; + bool Match; + + DependencyChecker(TemplateParameterList *Params) : Match(false) { + NamedDecl *ND = Params->getParam(0); + if (TemplateTypeParmDecl *PD = dyn_cast<TemplateTypeParmDecl>(ND)) { + Depth = PD->getDepth(); + } else if (NonTypeTemplateParmDecl *PD = + dyn_cast<NonTypeTemplateParmDecl>(ND)) { + Depth = PD->getDepth(); + } else { + Depth = cast<TemplateTemplateParmDecl>(ND)->getDepth(); + } + } + + bool Matches(unsigned ParmDepth) { + if (ParmDepth >= Depth) { + Match = true; + return true; + } + return false; + } + + bool VisitTemplateTypeParmType(const TemplateTypeParmType *T) { + return !Matches(T->getDepth()); + } + + bool TraverseTemplateName(TemplateName N) { + if (TemplateTemplateParmDecl *PD = + dyn_cast_or_null<TemplateTemplateParmDecl>(N.getAsTemplateDecl())) + if (Matches(PD->getDepth())) return false; + return super::TraverseTemplateName(N); + } + + bool VisitDeclRefExpr(DeclRefExpr *E) { + if (NonTypeTemplateParmDecl *PD = + dyn_cast<NonTypeTemplateParmDecl>(E->getDecl())) { + if (PD->getDepth() == Depth) { + Match = true; + return false; + } + } + return super::VisitDeclRefExpr(E); + } + + bool TraverseInjectedClassNameType(const InjectedClassNameType *T) { + return TraverseType(T->getInjectedSpecializationType()); + } +}; +} + +/// Determines whether a given type depends on the given parameter +/// list. +static bool +DependsOnTemplateParameters(QualType T, TemplateParameterList *Params) { + DependencyChecker Checker(Params); + Checker.TraverseType(T); + return Checker.Match; +} + +// Find the source range corresponding to the named type in the given +// nested-name-specifier, if any. +static SourceRange getRangeOfTypeInNestedNameSpecifier(ASTContext &Context, + QualType T, + const CXXScopeSpec &SS) { + NestedNameSpecifierLoc NNSLoc(SS.getScopeRep(), SS.location_data()); + while (NestedNameSpecifier *NNS = NNSLoc.getNestedNameSpecifier()) { + if (const Type *CurType = NNS->getAsType()) { + if (Context.hasSameUnqualifiedType(T, QualType(CurType, 0))) + return NNSLoc.getTypeLoc().getSourceRange(); + } else + break; + + NNSLoc = NNSLoc.getPrefix(); + } + + return SourceRange(); +} + +/// \brief Match the given template parameter lists to the given scope +/// specifier, returning the template parameter list that applies to the +/// name. +/// +/// \param DeclStartLoc the start of the declaration that has a scope +/// specifier or a template parameter list. +/// +/// \param DeclLoc The location of the declaration itself. +/// +/// \param SS the scope specifier that will be matched to the given template +/// parameter lists. This scope specifier precedes a qualified name that is +/// being declared. +/// +/// \param ParamLists the template parameter lists, from the outermost to the +/// innermost template parameter lists. +/// +/// \param NumParamLists the number of template parameter lists in ParamLists. +/// +/// \param IsFriend Whether to apply the slightly different rules for +/// matching template parameters to scope specifiers in friend +/// declarations. +/// +/// \param IsExplicitSpecialization will be set true if the entity being +/// declared is an explicit specialization, false otherwise. +/// +/// \returns the template parameter list, if any, that corresponds to the +/// name that is preceded by the scope specifier @p SS. This template +/// parameter list may have template parameters (if we're declaring a +/// template) or may have no template parameters (if we're declaring a +/// template specialization), or may be NULL (if what we're declaring isn't +/// itself a template). +TemplateParameterList * +Sema::MatchTemplateParametersToScopeSpecifier(SourceLocation DeclStartLoc, + SourceLocation DeclLoc, + const CXXScopeSpec &SS, + TemplateParameterList **ParamLists, + unsigned NumParamLists, + bool IsFriend, + bool &IsExplicitSpecialization, + bool &Invalid) { + IsExplicitSpecialization = false; + Invalid = false; + + // The sequence of nested types to which we will match up the template + // parameter lists. We first build this list by starting with the type named + // by the nested-name-specifier and walking out until we run out of types. + SmallVector<QualType, 4> NestedTypes; + QualType T; + if (SS.getScopeRep()) { + if (CXXRecordDecl *Record + = dyn_cast_or_null<CXXRecordDecl>(computeDeclContext(SS, true))) + T = Context.getTypeDeclType(Record); + else + T = QualType(SS.getScopeRep()->getAsType(), 0); + } + + // If we found an explicit specialization that prevents us from needing + // 'template<>' headers, this will be set to the location of that + // explicit specialization. + SourceLocation ExplicitSpecLoc; + + while (!T.isNull()) { + NestedTypes.push_back(T); + + // Retrieve the parent of a record type. + if (CXXRecordDecl *Record = T->getAsCXXRecordDecl()) { + // If this type is an explicit specialization, we're done. + if (ClassTemplateSpecializationDecl *Spec + = dyn_cast<ClassTemplateSpecializationDecl>(Record)) { + if (!isa<ClassTemplatePartialSpecializationDecl>(Spec) && + Spec->getSpecializationKind() == TSK_ExplicitSpecialization) { + ExplicitSpecLoc = Spec->getLocation(); + break; + } + } else if (Record->getTemplateSpecializationKind() + == TSK_ExplicitSpecialization) { + ExplicitSpecLoc = Record->getLocation(); + break; + } + + if (TypeDecl *Parent = dyn_cast<TypeDecl>(Record->getParent())) + T = Context.getTypeDeclType(Parent); + else + T = QualType(); + continue; + } + + if (const TemplateSpecializationType *TST + = T->getAs<TemplateSpecializationType>()) { + if (TemplateDecl *Template = TST->getTemplateName().getAsTemplateDecl()) { + if (TypeDecl *Parent = dyn_cast<TypeDecl>(Template->getDeclContext())) + T = Context.getTypeDeclType(Parent); + else + T = QualType(); + continue; + } + } + + // Look one step prior in a dependent template specialization type. + if (const DependentTemplateSpecializationType *DependentTST + = T->getAs<DependentTemplateSpecializationType>()) { + if (NestedNameSpecifier *NNS = DependentTST->getQualifier()) + T = QualType(NNS->getAsType(), 0); + else + T = QualType(); + continue; + } + + // Look one step prior in a dependent name type. + if (const DependentNameType *DependentName = T->getAs<DependentNameType>()){ + if (NestedNameSpecifier *NNS = DependentName->getQualifier()) + T = QualType(NNS->getAsType(), 0); + else + T = QualType(); + continue; + } + + // Retrieve the parent of an enumeration type. + if (const EnumType *EnumT = T->getAs<EnumType>()) { + // FIXME: Forward-declared enums require a TSK_ExplicitSpecialization + // check here. + EnumDecl *Enum = EnumT->getDecl(); + + // Get to the parent type. + if (TypeDecl *Parent = dyn_cast<TypeDecl>(Enum->getParent())) + T = Context.getTypeDeclType(Parent); + else + T = QualType(); + continue; + } + + T = QualType(); + } + // Reverse the nested types list, since we want to traverse from the outermost + // to the innermost while checking template-parameter-lists. + std::reverse(NestedTypes.begin(), NestedTypes.end()); + + // C++0x [temp.expl.spec]p17: + // A member or a member template may be nested within many + // enclosing class templates. In an explicit specialization for + // such a member, the member declaration shall be preceded by a + // template<> for each enclosing class template that is + // explicitly specialized. + bool SawNonEmptyTemplateParameterList = false; + unsigned ParamIdx = 0; + for (unsigned TypeIdx = 0, NumTypes = NestedTypes.size(); TypeIdx != NumTypes; + ++TypeIdx) { + T = NestedTypes[TypeIdx]; + + // Whether we expect a 'template<>' header. + bool NeedEmptyTemplateHeader = false; + + // Whether we expect a template header with parameters. + bool NeedNonemptyTemplateHeader = false; + + // For a dependent type, the set of template parameters that we + // expect to see. + TemplateParameterList *ExpectedTemplateParams = 0; + + // C++0x [temp.expl.spec]p15: + // A member or a member template may be nested within many enclosing + // class templates. In an explicit specialization for such a member, the + // member declaration shall be preceded by a template<> for each + // enclosing class template that is explicitly specialized. + if (CXXRecordDecl *Record = T->getAsCXXRecordDecl()) { + if (ClassTemplatePartialSpecializationDecl *Partial + = dyn_cast<ClassTemplatePartialSpecializationDecl>(Record)) { + ExpectedTemplateParams = Partial->getTemplateParameters(); + NeedNonemptyTemplateHeader = true; + } else if (Record->isDependentType()) { + if (Record->getDescribedClassTemplate()) { + ExpectedTemplateParams = Record->getDescribedClassTemplate() + ->getTemplateParameters(); + NeedNonemptyTemplateHeader = true; + } + } else if (ClassTemplateSpecializationDecl *Spec + = dyn_cast<ClassTemplateSpecializationDecl>(Record)) { + // C++0x [temp.expl.spec]p4: + // Members of an explicitly specialized class template are defined + // in the same manner as members of normal classes, and not using + // the template<> syntax. + if (Spec->getSpecializationKind() != TSK_ExplicitSpecialization) + NeedEmptyTemplateHeader = true; + else + continue; + } else if (Record->getTemplateSpecializationKind()) { + if (Record->getTemplateSpecializationKind() + != TSK_ExplicitSpecialization && + TypeIdx == NumTypes - 1) + IsExplicitSpecialization = true; + + continue; + } + } else if (const TemplateSpecializationType *TST + = T->getAs<TemplateSpecializationType>()) { + if (TemplateDecl *Template = TST->getTemplateName().getAsTemplateDecl()) { + ExpectedTemplateParams = Template->getTemplateParameters(); + NeedNonemptyTemplateHeader = true; + } + } else if (T->getAs<DependentTemplateSpecializationType>()) { + // FIXME: We actually could/should check the template arguments here + // against the corresponding template parameter list. + NeedNonemptyTemplateHeader = false; + } + + // C++ [temp.expl.spec]p16: + // In an explicit specialization declaration for a member of a class + // template or a member template that ap- pears in namespace scope, the + // member template and some of its enclosing class templates may remain + // unspecialized, except that the declaration shall not explicitly + // specialize a class member template if its en- closing class templates + // are not explicitly specialized as well. + if (ParamIdx < NumParamLists) { + if (ParamLists[ParamIdx]->size() == 0) { + if (SawNonEmptyTemplateParameterList) { + Diag(DeclLoc, diag::err_specialize_member_of_template) + << ParamLists[ParamIdx]->getSourceRange(); + Invalid = true; + IsExplicitSpecialization = false; + return 0; + } + } else + SawNonEmptyTemplateParameterList = true; + } + + if (NeedEmptyTemplateHeader) { + // If we're on the last of the types, and we need a 'template<>' header + // here, then it's an explicit specialization. + if (TypeIdx == NumTypes - 1) + IsExplicitSpecialization = true; + + if (ParamIdx < NumParamLists) { + if (ParamLists[ParamIdx]->size() > 0) { + // The header has template parameters when it shouldn't. Complain. + Diag(ParamLists[ParamIdx]->getTemplateLoc(), + diag::err_template_param_list_matches_nontemplate) + << T + << SourceRange(ParamLists[ParamIdx]->getLAngleLoc(), + ParamLists[ParamIdx]->getRAngleLoc()) + << getRangeOfTypeInNestedNameSpecifier(Context, T, SS); + Invalid = true; + return 0; + } + + // Consume this template header. + ++ParamIdx; + continue; + } + + if (!IsFriend) { + // We don't have a template header, but we should. + SourceLocation ExpectedTemplateLoc; + if (NumParamLists > 0) + ExpectedTemplateLoc = ParamLists[0]->getTemplateLoc(); + else + ExpectedTemplateLoc = DeclStartLoc; + + Diag(DeclLoc, diag::err_template_spec_needs_header) + << getRangeOfTypeInNestedNameSpecifier(Context, T, SS) + << FixItHint::CreateInsertion(ExpectedTemplateLoc, "template<> "); + } + + continue; + } + + if (NeedNonemptyTemplateHeader) { + // In friend declarations we can have template-ids which don't + // depend on the corresponding template parameter lists. But + // assume that empty parameter lists are supposed to match this + // template-id. + if (IsFriend && T->isDependentType()) { + if (ParamIdx < NumParamLists && + DependsOnTemplateParameters(T, ParamLists[ParamIdx])) + ExpectedTemplateParams = 0; + else + continue; + } + + if (ParamIdx < NumParamLists) { + // Check the template parameter list, if we can. + if (ExpectedTemplateParams && + !TemplateParameterListsAreEqual(ParamLists[ParamIdx], + ExpectedTemplateParams, + true, TPL_TemplateMatch)) + Invalid = true; + + if (!Invalid && + CheckTemplateParameterList(ParamLists[ParamIdx], 0, + TPC_ClassTemplateMember)) + Invalid = true; + + ++ParamIdx; + continue; + } + + Diag(DeclLoc, diag::err_template_spec_needs_template_parameters) + << T + << getRangeOfTypeInNestedNameSpecifier(Context, T, SS); + Invalid = true; + continue; + } + } + + // If there were at least as many template-ids as there were template + // parameter lists, then there are no template parameter lists remaining for + // the declaration itself. + if (ParamIdx >= NumParamLists) + return 0; + + // If there were too many template parameter lists, complain about that now. + if (ParamIdx < NumParamLists - 1) { + bool HasAnyExplicitSpecHeader = false; + bool AllExplicitSpecHeaders = true; + for (unsigned I = ParamIdx; I != NumParamLists - 1; ++I) { + if (ParamLists[I]->size() == 0) + HasAnyExplicitSpecHeader = true; + else + AllExplicitSpecHeaders = false; + } + + Diag(ParamLists[ParamIdx]->getTemplateLoc(), + AllExplicitSpecHeaders? diag::warn_template_spec_extra_headers + : diag::err_template_spec_extra_headers) + << SourceRange(ParamLists[ParamIdx]->getTemplateLoc(), + ParamLists[NumParamLists - 2]->getRAngleLoc()); + + // If there was a specialization somewhere, such that 'template<>' is + // not required, and there were any 'template<>' headers, note where the + // specialization occurred. + if (ExplicitSpecLoc.isValid() && HasAnyExplicitSpecHeader) + Diag(ExplicitSpecLoc, + diag::note_explicit_template_spec_does_not_need_header) + << NestedTypes.back(); + + // We have a template parameter list with no corresponding scope, which + // means that the resulting template declaration can't be instantiated + // properly (we'll end up with dependent nodes when we shouldn't). + if (!AllExplicitSpecHeaders) + Invalid = true; + } + + // C++ [temp.expl.spec]p16: + // In an explicit specialization declaration for a member of a class + // template or a member template that ap- pears in namespace scope, the + // member template and some of its enclosing class templates may remain + // unspecialized, except that the declaration shall not explicitly + // specialize a class member template if its en- closing class templates + // are not explicitly specialized as well. + if (ParamLists[NumParamLists - 1]->size() == 0 && + SawNonEmptyTemplateParameterList) { + Diag(DeclLoc, diag::err_specialize_member_of_template) + << ParamLists[ParamIdx]->getSourceRange(); + Invalid = true; + IsExplicitSpecialization = false; + return 0; + } + + // Return the last template parameter list, which corresponds to the + // entity being declared. + return ParamLists[NumParamLists - 1]; +} + +void Sema::NoteAllFoundTemplates(TemplateName Name) { + if (TemplateDecl *Template = Name.getAsTemplateDecl()) { + Diag(Template->getLocation(), diag::note_template_declared_here) + << (isa<FunctionTemplateDecl>(Template)? 0 + : isa<ClassTemplateDecl>(Template)? 1 + : isa<TypeAliasTemplateDecl>(Template)? 2 + : 3) + << Template->getDeclName(); + return; + } + + if (OverloadedTemplateStorage *OST = Name.getAsOverloadedTemplate()) { + for (OverloadedTemplateStorage::iterator I = OST->begin(), + IEnd = OST->end(); + I != IEnd; ++I) + Diag((*I)->getLocation(), diag::note_template_declared_here) + << 0 << (*I)->getDeclName(); + + return; + } +} + +QualType Sema::CheckTemplateIdType(TemplateName Name, + SourceLocation TemplateLoc, + TemplateArgumentListInfo &TemplateArgs) { + DependentTemplateName *DTN + = Name.getUnderlying().getAsDependentTemplateName(); + if (DTN && DTN->isIdentifier()) + // When building a template-id where the template-name is dependent, + // assume the template is a type template. Either our assumption is + // correct, or the code is ill-formed and will be diagnosed when the + // dependent name is substituted. + return Context.getDependentTemplateSpecializationType(ETK_None, + DTN->getQualifier(), + DTN->getIdentifier(), + TemplateArgs); + + TemplateDecl *Template = Name.getAsTemplateDecl(); + if (!Template || isa<FunctionTemplateDecl>(Template)) { + // We might have a substituted template template parameter pack. If so, + // build a template specialization type for it. + if (Name.getAsSubstTemplateTemplateParmPack()) + return Context.getTemplateSpecializationType(Name, TemplateArgs); + + Diag(TemplateLoc, diag::err_template_id_not_a_type) + << Name; + NoteAllFoundTemplates(Name); + return QualType(); + } + + // Check that the template argument list is well-formed for this + // template. + SmallVector<TemplateArgument, 4> Converted; + bool ExpansionIntoFixedList = false; + if (CheckTemplateArgumentList(Template, TemplateLoc, TemplateArgs, + false, Converted, &ExpansionIntoFixedList)) + return QualType(); + + QualType CanonType; + + bool InstantiationDependent = false; + TypeAliasTemplateDecl *AliasTemplate = 0; + if (!ExpansionIntoFixedList && + (AliasTemplate = dyn_cast<TypeAliasTemplateDecl>(Template))) { + // Find the canonical type for this type alias template specialization. + TypeAliasDecl *Pattern = AliasTemplate->getTemplatedDecl(); + if (Pattern->isInvalidDecl()) + return QualType(); + + TemplateArgumentList TemplateArgs(TemplateArgumentList::OnStack, + Converted.data(), Converted.size()); + + // Only substitute for the innermost template argument list. + MultiLevelTemplateArgumentList TemplateArgLists; + TemplateArgLists.addOuterTemplateArguments(&TemplateArgs); + unsigned Depth = AliasTemplate->getTemplateParameters()->getDepth(); + for (unsigned I = 0; I < Depth; ++I) + TemplateArgLists.addOuterTemplateArguments(0, 0); + + InstantiatingTemplate Inst(*this, TemplateLoc, Template); + CanonType = SubstType(Pattern->getUnderlyingType(), + TemplateArgLists, AliasTemplate->getLocation(), + AliasTemplate->getDeclName()); + if (CanonType.isNull()) + return QualType(); + } else if (Name.isDependent() || + TemplateSpecializationType::anyDependentTemplateArguments( + TemplateArgs, InstantiationDependent)) { + // This class template specialization is a dependent + // type. Therefore, its canonical type is another class template + // specialization type that contains all of the converted + // arguments in canonical form. This ensures that, e.g., A<T> and + // A<T, T> have identical types when A is declared as: + // + // template<typename T, typename U = T> struct A; + TemplateName CanonName = Context.getCanonicalTemplateName(Name); + CanonType = Context.getTemplateSpecializationType(CanonName, + Converted.data(), + Converted.size()); + + // FIXME: CanonType is not actually the canonical type, and unfortunately + // it is a TemplateSpecializationType that we will never use again. + // In the future, we need to teach getTemplateSpecializationType to only + // build the canonical type and return that to us. + CanonType = Context.getCanonicalType(CanonType); + + // This might work out to be a current instantiation, in which + // case the canonical type needs to be the InjectedClassNameType. + // + // TODO: in theory this could be a simple hashtable lookup; most + // changes to CurContext don't change the set of current + // instantiations. + if (isa<ClassTemplateDecl>(Template)) { + for (DeclContext *Ctx = CurContext; Ctx; Ctx = Ctx->getLookupParent()) { + // If we get out to a namespace, we're done. + if (Ctx->isFileContext()) break; + + // If this isn't a record, keep looking. + CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Ctx); + if (!Record) continue; + + // Look for one of the two cases with InjectedClassNameTypes + // and check whether it's the same template. + if (!isa<ClassTemplatePartialSpecializationDecl>(Record) && + !Record->getDescribedClassTemplate()) + continue; + + // Fetch the injected class name type and check whether its + // injected type is equal to the type we just built. + QualType ICNT = Context.getTypeDeclType(Record); + QualType Injected = cast<InjectedClassNameType>(ICNT) + ->getInjectedSpecializationType(); + + if (CanonType != Injected->getCanonicalTypeInternal()) + continue; + + // If so, the canonical type of this TST is the injected + // class name type of the record we just found. + assert(ICNT.isCanonical()); + CanonType = ICNT; + break; + } + } + } else if (ClassTemplateDecl *ClassTemplate + = dyn_cast<ClassTemplateDecl>(Template)) { + // Find the class template specialization declaration that + // corresponds to these arguments. + void *InsertPos = 0; + ClassTemplateSpecializationDecl *Decl + = ClassTemplate->findSpecialization(Converted.data(), Converted.size(), + InsertPos); + if (!Decl) { + // This is the first time we have referenced this class template + // specialization. Create the canonical declaration and add it to + // the set of specializations. + Decl = ClassTemplateSpecializationDecl::Create(Context, + ClassTemplate->getTemplatedDecl()->getTagKind(), + ClassTemplate->getDeclContext(), + ClassTemplate->getTemplatedDecl()->getLocStart(), + ClassTemplate->getLocation(), + ClassTemplate, + Converted.data(), + Converted.size(), 0); + ClassTemplate->AddSpecialization(Decl, InsertPos); + Decl->setLexicalDeclContext(CurContext); + } + + CanonType = Context.getTypeDeclType(Decl); + assert(isa<RecordType>(CanonType) && + "type of non-dependent specialization is not a RecordType"); + } + + // Build the fully-sugared type for this class template + // specialization, which refers back to the class template + // specialization we created or found. + return Context.getTemplateSpecializationType(Name, TemplateArgs, CanonType); +} + +TypeResult +Sema::ActOnTemplateIdType(CXXScopeSpec &SS, SourceLocation TemplateKWLoc, + TemplateTy TemplateD, SourceLocation TemplateLoc, + SourceLocation LAngleLoc, + ASTTemplateArgsPtr TemplateArgsIn, + SourceLocation RAngleLoc, + bool IsCtorOrDtorName) { + if (SS.isInvalid()) + return true; + + TemplateName Template = TemplateD.getAsVal<TemplateName>(); + + // Translate the parser's template argument list in our AST format. + TemplateArgumentListInfo TemplateArgs(LAngleLoc, RAngleLoc); + translateTemplateArguments(TemplateArgsIn, TemplateArgs); + + if (DependentTemplateName *DTN = Template.getAsDependentTemplateName()) { + QualType T + = Context.getDependentTemplateSpecializationType(ETK_None, + DTN->getQualifier(), + DTN->getIdentifier(), + TemplateArgs); + // Build type-source information. + TypeLocBuilder TLB; + DependentTemplateSpecializationTypeLoc SpecTL + = TLB.push<DependentTemplateSpecializationTypeLoc>(T); + SpecTL.setElaboratedKeywordLoc(SourceLocation()); + SpecTL.setQualifierLoc(SS.getWithLocInContext(Context)); + SpecTL.setTemplateKeywordLoc(TemplateKWLoc); + SpecTL.setTemplateNameLoc(TemplateLoc); + SpecTL.setLAngleLoc(LAngleLoc); + SpecTL.setRAngleLoc(RAngleLoc); + for (unsigned I = 0, N = SpecTL.getNumArgs(); I != N; ++I) + SpecTL.setArgLocInfo(I, TemplateArgs[I].getLocInfo()); + return CreateParsedType(T, TLB.getTypeSourceInfo(Context, T)); + } + + QualType Result = CheckTemplateIdType(Template, TemplateLoc, TemplateArgs); + TemplateArgsIn.release(); + + if (Result.isNull()) + return true; + + // Build type-source information. + TypeLocBuilder TLB; + TemplateSpecializationTypeLoc SpecTL + = TLB.push<TemplateSpecializationTypeLoc>(Result); + SpecTL.setTemplateKeywordLoc(TemplateKWLoc); + SpecTL.setTemplateNameLoc(TemplateLoc); + SpecTL.setLAngleLoc(LAngleLoc); + SpecTL.setRAngleLoc(RAngleLoc); + for (unsigned i = 0, e = SpecTL.getNumArgs(); i != e; ++i) + SpecTL.setArgLocInfo(i, TemplateArgs[i].getLocInfo()); + + // NOTE: avoid constructing an ElaboratedTypeLoc if this is a + // constructor or destructor name (in such a case, the scope specifier + // will be attached to the enclosing Decl or Expr node). + if (SS.isNotEmpty() && !IsCtorOrDtorName) { + // Create an elaborated-type-specifier containing the nested-name-specifier. + Result = Context.getElaboratedType(ETK_None, SS.getScopeRep(), Result); + ElaboratedTypeLoc ElabTL = TLB.push<ElaboratedTypeLoc>(Result); + ElabTL.setElaboratedKeywordLoc(SourceLocation()); + ElabTL.setQualifierLoc(SS.getWithLocInContext(Context)); + } + + return CreateParsedType(Result, TLB.getTypeSourceInfo(Context, Result)); +} + +TypeResult Sema::ActOnTagTemplateIdType(TagUseKind TUK, + TypeSpecifierType TagSpec, + SourceLocation TagLoc, + CXXScopeSpec &SS, + SourceLocation TemplateKWLoc, + TemplateTy TemplateD, + SourceLocation TemplateLoc, + SourceLocation LAngleLoc, + ASTTemplateArgsPtr TemplateArgsIn, + SourceLocation RAngleLoc) { + TemplateName Template = TemplateD.getAsVal<TemplateName>(); + + // Translate the parser's template argument list in our AST format. + TemplateArgumentListInfo TemplateArgs(LAngleLoc, RAngleLoc); + translateTemplateArguments(TemplateArgsIn, TemplateArgs); + + // Determine the tag kind + TagTypeKind TagKind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec); + ElaboratedTypeKeyword Keyword + = TypeWithKeyword::getKeywordForTagTypeKind(TagKind); + + if (DependentTemplateName *DTN = Template.getAsDependentTemplateName()) { + QualType T = Context.getDependentTemplateSpecializationType(Keyword, + DTN->getQualifier(), + DTN->getIdentifier(), + TemplateArgs); + + // Build type-source information. + TypeLocBuilder TLB; + DependentTemplateSpecializationTypeLoc SpecTL + = TLB.push<DependentTemplateSpecializationTypeLoc>(T); + SpecTL.setElaboratedKeywordLoc(TagLoc); + SpecTL.setQualifierLoc(SS.getWithLocInContext(Context)); + SpecTL.setTemplateKeywordLoc(TemplateKWLoc); + SpecTL.setTemplateNameLoc(TemplateLoc); + SpecTL.setLAngleLoc(LAngleLoc); + SpecTL.setRAngleLoc(RAngleLoc); + for (unsigned I = 0, N = SpecTL.getNumArgs(); I != N; ++I) + SpecTL.setArgLocInfo(I, TemplateArgs[I].getLocInfo()); + return CreateParsedType(T, TLB.getTypeSourceInfo(Context, T)); + } + + if (TypeAliasTemplateDecl *TAT = + dyn_cast_or_null<TypeAliasTemplateDecl>(Template.getAsTemplateDecl())) { + // C++0x [dcl.type.elab]p2: + // If the identifier resolves to a typedef-name or the simple-template-id + // resolves to an alias template specialization, the + // elaborated-type-specifier is ill-formed. + Diag(TemplateLoc, diag::err_tag_reference_non_tag) << 4; + Diag(TAT->getLocation(), diag::note_declared_at); + } + + QualType Result = CheckTemplateIdType(Template, TemplateLoc, TemplateArgs); + if (Result.isNull()) + return TypeResult(true); + + // Check the tag kind + if (const RecordType *RT = Result->getAs<RecordType>()) { + RecordDecl *D = RT->getDecl(); + + IdentifierInfo *Id = D->getIdentifier(); + assert(Id && "templated class must have an identifier"); + + if (!isAcceptableTagRedeclaration(D, TagKind, TUK == TUK_Definition, + TagLoc, *Id)) { + Diag(TagLoc, diag::err_use_with_wrong_tag) + << Result + << FixItHint::CreateReplacement(SourceRange(TagLoc), D->getKindName()); + Diag(D->getLocation(), diag::note_previous_use); + } + } + + // Provide source-location information for the template specialization. + TypeLocBuilder TLB; + TemplateSpecializationTypeLoc SpecTL + = TLB.push<TemplateSpecializationTypeLoc>(Result); + SpecTL.setTemplateKeywordLoc(TemplateKWLoc); + SpecTL.setTemplateNameLoc(TemplateLoc); + SpecTL.setLAngleLoc(LAngleLoc); + SpecTL.setRAngleLoc(RAngleLoc); + for (unsigned i = 0, e = SpecTL.getNumArgs(); i != e; ++i) + SpecTL.setArgLocInfo(i, TemplateArgs[i].getLocInfo()); + + // Construct an elaborated type containing the nested-name-specifier (if any) + // and tag keyword. + Result = Context.getElaboratedType(Keyword, SS.getScopeRep(), Result); + ElaboratedTypeLoc ElabTL = TLB.push<ElaboratedTypeLoc>(Result); + ElabTL.setElaboratedKeywordLoc(TagLoc); + ElabTL.setQualifierLoc(SS.getWithLocInContext(Context)); + return CreateParsedType(Result, TLB.getTypeSourceInfo(Context, Result)); +} + +ExprResult Sema::BuildTemplateIdExpr(const CXXScopeSpec &SS, + SourceLocation TemplateKWLoc, + LookupResult &R, + bool RequiresADL, + const TemplateArgumentListInfo *TemplateArgs) { + // FIXME: Can we do any checking at this point? I guess we could check the + // template arguments that we have against the template name, if the template + // name refers to a single template. That's not a terribly common case, + // though. + // foo<int> could identify a single function unambiguously + // This approach does NOT work, since f<int>(1); + // gets resolved prior to resorting to overload resolution + // i.e., template<class T> void f(double); + // vs template<class T, class U> void f(U); + + // These should be filtered out by our callers. + assert(!R.empty() && "empty lookup results when building templateid"); + assert(!R.isAmbiguous() && "ambiguous lookup when building templateid"); + + // We don't want lookup warnings at this point. + R.suppressDiagnostics(); + + UnresolvedLookupExpr *ULE + = UnresolvedLookupExpr::Create(Context, R.getNamingClass(), + SS.getWithLocInContext(Context), + TemplateKWLoc, + R.getLookupNameInfo(), + RequiresADL, TemplateArgs, + R.begin(), R.end()); + + return Owned(ULE); +} + +// We actually only call this from template instantiation. +ExprResult +Sema::BuildQualifiedTemplateIdExpr(CXXScopeSpec &SS, + SourceLocation TemplateKWLoc, + const DeclarationNameInfo &NameInfo, + const TemplateArgumentListInfo *TemplateArgs) { + assert(TemplateArgs || TemplateKWLoc.isValid()); + DeclContext *DC; + if (!(DC = computeDeclContext(SS, false)) || + DC->isDependentContext() || + RequireCompleteDeclContext(SS, DC)) + return BuildDependentDeclRefExpr(SS, TemplateKWLoc, NameInfo, TemplateArgs); + + bool MemberOfUnknownSpecialization; + LookupResult R(*this, NameInfo, LookupOrdinaryName); + LookupTemplateName(R, (Scope*) 0, SS, QualType(), /*Entering*/ false, + MemberOfUnknownSpecialization); + + if (R.isAmbiguous()) + return ExprError(); + + if (R.empty()) { + Diag(NameInfo.getLoc(), diag::err_template_kw_refers_to_non_template) + << NameInfo.getName() << SS.getRange(); + return ExprError(); + } + + if (ClassTemplateDecl *Temp = R.getAsSingle<ClassTemplateDecl>()) { + Diag(NameInfo.getLoc(), diag::err_template_kw_refers_to_class_template) + << (NestedNameSpecifier*) SS.getScopeRep() + << NameInfo.getName() << SS.getRange(); + Diag(Temp->getLocation(), diag::note_referenced_class_template); + return ExprError(); + } + + return BuildTemplateIdExpr(SS, TemplateKWLoc, R, /*ADL*/ false, TemplateArgs); +} + +/// \brief Form a dependent template name. +/// +/// This action forms a dependent template name given the template +/// name and its (presumably dependent) scope specifier. For +/// example, given "MetaFun::template apply", the scope specifier \p +/// SS will be "MetaFun::", \p TemplateKWLoc contains the location +/// of the "template" keyword, and "apply" is the \p Name. +TemplateNameKind Sema::ActOnDependentTemplateName(Scope *S, + CXXScopeSpec &SS, + SourceLocation TemplateKWLoc, + UnqualifiedId &Name, + ParsedType ObjectType, + bool EnteringContext, + TemplateTy &Result) { + if (TemplateKWLoc.isValid() && S && !S->getTemplateParamParent()) + Diag(TemplateKWLoc, + getLangOpts().CPlusPlus0x ? + diag::warn_cxx98_compat_template_outside_of_template : + diag::ext_template_outside_of_template) + << FixItHint::CreateRemoval(TemplateKWLoc); + + DeclContext *LookupCtx = 0; + if (SS.isSet()) + LookupCtx = computeDeclContext(SS, EnteringContext); + if (!LookupCtx && ObjectType) + LookupCtx = computeDeclContext(ObjectType.get()); + if (LookupCtx) { + // C++0x [temp.names]p5: + // If a name prefixed by the keyword template is not the name of + // a template, the program is ill-formed. [Note: the keyword + // template may not be applied to non-template members of class + // templates. -end note ] [ Note: as is the case with the + // typename prefix, the template prefix is allowed in cases + // where it is not strictly necessary; i.e., when the + // nested-name-specifier or the expression on the left of the -> + // or . is not dependent on a template-parameter, or the use + // does not appear in the scope of a template. -end note] + // + // Note: C++03 was more strict here, because it banned the use of + // the "template" keyword prior to a template-name that was not a + // dependent name. C++ DR468 relaxed this requirement (the + // "template" keyword is now permitted). We follow the C++0x + // rules, even in C++03 mode with a warning, retroactively applying the DR. + bool MemberOfUnknownSpecialization; + TemplateNameKind TNK = isTemplateName(0, SS, TemplateKWLoc.isValid(), Name, + ObjectType, EnteringContext, Result, + MemberOfUnknownSpecialization); + if (TNK == TNK_Non_template && LookupCtx->isDependentContext() && + isa<CXXRecordDecl>(LookupCtx) && + (!cast<CXXRecordDecl>(LookupCtx)->hasDefinition() || + cast<CXXRecordDecl>(LookupCtx)->hasAnyDependentBases())) { + // This is a dependent template. Handle it below. + } else if (TNK == TNK_Non_template) { + Diag(Name.getLocStart(), + diag::err_template_kw_refers_to_non_template) + << GetNameFromUnqualifiedId(Name).getName() + << Name.getSourceRange() + << TemplateKWLoc; + return TNK_Non_template; + } else { + // We found something; return it. + return TNK; + } + } + + NestedNameSpecifier *Qualifier + = static_cast<NestedNameSpecifier *>(SS.getScopeRep()); + + switch (Name.getKind()) { + case UnqualifiedId::IK_Identifier: + Result = TemplateTy::make(Context.getDependentTemplateName(Qualifier, + Name.Identifier)); + return TNK_Dependent_template_name; + + case UnqualifiedId::IK_OperatorFunctionId: + Result = TemplateTy::make(Context.getDependentTemplateName(Qualifier, + Name.OperatorFunctionId.Operator)); + return TNK_Dependent_template_name; + + case UnqualifiedId::IK_LiteralOperatorId: + llvm_unreachable( + "We don't support these; Parse shouldn't have allowed propagation"); + + default: + break; + } + + Diag(Name.getLocStart(), + diag::err_template_kw_refers_to_non_template) + << GetNameFromUnqualifiedId(Name).getName() + << Name.getSourceRange() + << TemplateKWLoc; + return TNK_Non_template; +} + +bool Sema::CheckTemplateTypeArgument(TemplateTypeParmDecl *Param, + const TemplateArgumentLoc &AL, + SmallVectorImpl<TemplateArgument> &Converted) { + const TemplateArgument &Arg = AL.getArgument(); + + // Check template type parameter. + switch(Arg.getKind()) { + case TemplateArgument::Type: + // C++ [temp.arg.type]p1: + // A template-argument for a template-parameter which is a + // type shall be a type-id. + break; + case TemplateArgument::Template: { + // We have a template type parameter but the template argument + // is a template without any arguments. + SourceRange SR = AL.getSourceRange(); + TemplateName Name = Arg.getAsTemplate(); + Diag(SR.getBegin(), diag::err_template_missing_args) + << Name << SR; + if (TemplateDecl *Decl = Name.getAsTemplateDecl()) + Diag(Decl->getLocation(), diag::note_template_decl_here); + + return true; + } + default: { + // We have a template type parameter but the template argument + // is not a type. + SourceRange SR = AL.getSourceRange(); + Diag(SR.getBegin(), diag::err_template_arg_must_be_type) << SR; + Diag(Param->getLocation(), diag::note_template_param_here); + + return true; + } + } + + if (CheckTemplateArgument(Param, AL.getTypeSourceInfo())) + return true; + + // Add the converted template type argument. + QualType ArgType = Context.getCanonicalType(Arg.getAsType()); + + // Objective-C ARC: + // If an explicitly-specified template argument type is a lifetime type + // with no lifetime qualifier, the __strong lifetime qualifier is inferred. + if (getLangOpts().ObjCAutoRefCount && + ArgType->isObjCLifetimeType() && + !ArgType.getObjCLifetime()) { + Qualifiers Qs; + Qs.setObjCLifetime(Qualifiers::OCL_Strong); + ArgType = Context.getQualifiedType(ArgType, Qs); + } + + Converted.push_back(TemplateArgument(ArgType)); + return false; +} + +/// \brief Substitute template arguments into the default template argument for +/// the given template type parameter. +/// +/// \param SemaRef the semantic analysis object for which we are performing +/// the substitution. +/// +/// \param Template the template that we are synthesizing template arguments +/// for. +/// +/// \param TemplateLoc the location of the template name that started the +/// template-id we are checking. +/// +/// \param RAngleLoc the location of the right angle bracket ('>') that +/// terminates the template-id. +/// +/// \param Param the template template parameter whose default we are +/// substituting into. +/// +/// \param Converted the list of template arguments provided for template +/// parameters that precede \p Param in the template parameter list. +/// \returns the substituted template argument, or NULL if an error occurred. +static TypeSourceInfo * +SubstDefaultTemplateArgument(Sema &SemaRef, + TemplateDecl *Template, + SourceLocation TemplateLoc, + SourceLocation RAngleLoc, + TemplateTypeParmDecl *Param, + SmallVectorImpl<TemplateArgument> &Converted) { + TypeSourceInfo *ArgType = Param->getDefaultArgumentInfo(); + + // If the argument type is dependent, instantiate it now based + // on the previously-computed template arguments. + if (ArgType->getType()->isDependentType()) { + TemplateArgumentList TemplateArgs(TemplateArgumentList::OnStack, + Converted.data(), Converted.size()); + + MultiLevelTemplateArgumentList AllTemplateArgs + = SemaRef.getTemplateInstantiationArgs(Template, &TemplateArgs); + + Sema::InstantiatingTemplate Inst(SemaRef, TemplateLoc, + Template, Converted.data(), + Converted.size(), + SourceRange(TemplateLoc, RAngleLoc)); + + ArgType = SemaRef.SubstType(ArgType, AllTemplateArgs, + Param->getDefaultArgumentLoc(), + Param->getDeclName()); + } + + return ArgType; +} + +/// \brief Substitute template arguments into the default template argument for +/// the given non-type template parameter. +/// +/// \param SemaRef the semantic analysis object for which we are performing +/// the substitution. +/// +/// \param Template the template that we are synthesizing template arguments +/// for. +/// +/// \param TemplateLoc the location of the template name that started the +/// template-id we are checking. +/// +/// \param RAngleLoc the location of the right angle bracket ('>') that +/// terminates the template-id. +/// +/// \param Param the non-type template parameter whose default we are +/// substituting into. +/// +/// \param Converted the list of template arguments provided for template +/// parameters that precede \p Param in the template parameter list. +/// +/// \returns the substituted template argument, or NULL if an error occurred. +static ExprResult +SubstDefaultTemplateArgument(Sema &SemaRef, + TemplateDecl *Template, + SourceLocation TemplateLoc, + SourceLocation RAngleLoc, + NonTypeTemplateParmDecl *Param, + SmallVectorImpl<TemplateArgument> &Converted) { + TemplateArgumentList TemplateArgs(TemplateArgumentList::OnStack, + Converted.data(), Converted.size()); + + MultiLevelTemplateArgumentList AllTemplateArgs + = SemaRef.getTemplateInstantiationArgs(Template, &TemplateArgs); + + Sema::InstantiatingTemplate Inst(SemaRef, TemplateLoc, + Template, Converted.data(), + Converted.size(), + SourceRange(TemplateLoc, RAngleLoc)); + + return SemaRef.SubstExpr(Param->getDefaultArgument(), AllTemplateArgs); +} + +/// \brief Substitute template arguments into the default template argument for +/// the given template template parameter. +/// +/// \param SemaRef the semantic analysis object for which we are performing +/// the substitution. +/// +/// \param Template the template that we are synthesizing template arguments +/// for. +/// +/// \param TemplateLoc the location of the template name that started the +/// template-id we are checking. +/// +/// \param RAngleLoc the location of the right angle bracket ('>') that +/// terminates the template-id. +/// +/// \param Param the template template parameter whose default we are +/// substituting into. +/// +/// \param Converted the list of template arguments provided for template +/// parameters that precede \p Param in the template parameter list. +/// +/// \param QualifierLoc Will be set to the nested-name-specifier (with +/// source-location information) that precedes the template name. +/// +/// \returns the substituted template argument, or NULL if an error occurred. +static TemplateName +SubstDefaultTemplateArgument(Sema &SemaRef, + TemplateDecl *Template, + SourceLocation TemplateLoc, + SourceLocation RAngleLoc, + TemplateTemplateParmDecl *Param, + SmallVectorImpl<TemplateArgument> &Converted, + NestedNameSpecifierLoc &QualifierLoc) { + TemplateArgumentList TemplateArgs(TemplateArgumentList::OnStack, + Converted.data(), Converted.size()); + + MultiLevelTemplateArgumentList AllTemplateArgs + = SemaRef.getTemplateInstantiationArgs(Template, &TemplateArgs); + + Sema::InstantiatingTemplate Inst(SemaRef, TemplateLoc, + Template, Converted.data(), + Converted.size(), + SourceRange(TemplateLoc, RAngleLoc)); + + // Substitute into the nested-name-specifier first, + QualifierLoc = Param->getDefaultArgument().getTemplateQualifierLoc(); + if (QualifierLoc) { + QualifierLoc = SemaRef.SubstNestedNameSpecifierLoc(QualifierLoc, + AllTemplateArgs); + if (!QualifierLoc) + return TemplateName(); + } + + return SemaRef.SubstTemplateName(QualifierLoc, + Param->getDefaultArgument().getArgument().getAsTemplate(), + Param->getDefaultArgument().getTemplateNameLoc(), + AllTemplateArgs); +} + +/// \brief If the given template parameter has a default template +/// argument, substitute into that default template argument and +/// return the corresponding template argument. +TemplateArgumentLoc +Sema::SubstDefaultTemplateArgumentIfAvailable(TemplateDecl *Template, + SourceLocation TemplateLoc, + SourceLocation RAngleLoc, + Decl *Param, + SmallVectorImpl<TemplateArgument> &Converted) { + if (TemplateTypeParmDecl *TypeParm = dyn_cast<TemplateTypeParmDecl>(Param)) { + if (!TypeParm->hasDefaultArgument()) + return TemplateArgumentLoc(); + + TypeSourceInfo *DI = SubstDefaultTemplateArgument(*this, Template, + TemplateLoc, + RAngleLoc, + TypeParm, + Converted); + if (DI) + return TemplateArgumentLoc(TemplateArgument(DI->getType()), DI); + + return TemplateArgumentLoc(); + } + + if (NonTypeTemplateParmDecl *NonTypeParm + = dyn_cast<NonTypeTemplateParmDecl>(Param)) { + if (!NonTypeParm->hasDefaultArgument()) + return TemplateArgumentLoc(); + + ExprResult Arg = SubstDefaultTemplateArgument(*this, Template, + TemplateLoc, + RAngleLoc, + NonTypeParm, + Converted); + if (Arg.isInvalid()) + return TemplateArgumentLoc(); + + Expr *ArgE = Arg.takeAs<Expr>(); + return TemplateArgumentLoc(TemplateArgument(ArgE), ArgE); + } + + TemplateTemplateParmDecl *TempTempParm + = cast<TemplateTemplateParmDecl>(Param); + if (!TempTempParm->hasDefaultArgument()) + return TemplateArgumentLoc(); + + + NestedNameSpecifierLoc QualifierLoc; + TemplateName TName = SubstDefaultTemplateArgument(*this, Template, + TemplateLoc, + RAngleLoc, + TempTempParm, + Converted, + QualifierLoc); + if (TName.isNull()) + return TemplateArgumentLoc(); + + return TemplateArgumentLoc(TemplateArgument(TName), + TempTempParm->getDefaultArgument().getTemplateQualifierLoc(), + TempTempParm->getDefaultArgument().getTemplateNameLoc()); +} + +/// \brief Check that the given template argument corresponds to the given +/// template parameter. +/// +/// \param Param The template parameter against which the argument will be +/// checked. +/// +/// \param Arg The template argument. +/// +/// \param Template The template in which the template argument resides. +/// +/// \param TemplateLoc The location of the template name for the template +/// whose argument list we're matching. +/// +/// \param RAngleLoc The location of the right angle bracket ('>') that closes +/// the template argument list. +/// +/// \param ArgumentPackIndex The index into the argument pack where this +/// argument will be placed. Only valid if the parameter is a parameter pack. +/// +/// \param Converted The checked, converted argument will be added to the +/// end of this small vector. +/// +/// \param CTAK Describes how we arrived at this particular template argument: +/// explicitly written, deduced, etc. +/// +/// \returns true on error, false otherwise. +bool Sema::CheckTemplateArgument(NamedDecl *Param, + const TemplateArgumentLoc &Arg, + NamedDecl *Template, + SourceLocation TemplateLoc, + SourceLocation RAngleLoc, + unsigned ArgumentPackIndex, + SmallVectorImpl<TemplateArgument> &Converted, + CheckTemplateArgumentKind CTAK) { + // Check template type parameters. + if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(Param)) + return CheckTemplateTypeArgument(TTP, Arg, Converted); + + // Check non-type template parameters. + if (NonTypeTemplateParmDecl *NTTP =dyn_cast<NonTypeTemplateParmDecl>(Param)) { + // Do substitution on the type of the non-type template parameter + // with the template arguments we've seen thus far. But if the + // template has a dependent context then we cannot substitute yet. + QualType NTTPType = NTTP->getType(); + if (NTTP->isParameterPack() && NTTP->isExpandedParameterPack()) + NTTPType = NTTP->getExpansionType(ArgumentPackIndex); + + if (NTTPType->isDependentType() && + !isa<TemplateTemplateParmDecl>(Template) && + !Template->getDeclContext()->isDependentContext()) { + // Do substitution on the type of the non-type template parameter. + InstantiatingTemplate Inst(*this, TemplateLoc, Template, + NTTP, Converted.data(), Converted.size(), + SourceRange(TemplateLoc, RAngleLoc)); + + TemplateArgumentList TemplateArgs(TemplateArgumentList::OnStack, + Converted.data(), Converted.size()); + NTTPType = SubstType(NTTPType, + MultiLevelTemplateArgumentList(TemplateArgs), + NTTP->getLocation(), + NTTP->getDeclName()); + // If that worked, check the non-type template parameter type + // for validity. + if (!NTTPType.isNull()) + NTTPType = CheckNonTypeTemplateParameterType(NTTPType, + NTTP->getLocation()); + if (NTTPType.isNull()) + return true; + } + + switch (Arg.getArgument().getKind()) { + case TemplateArgument::Null: + llvm_unreachable("Should never see a NULL template argument here"); + + case TemplateArgument::Expression: { + TemplateArgument Result; + ExprResult Res = + CheckTemplateArgument(NTTP, NTTPType, Arg.getArgument().getAsExpr(), + Result, CTAK); + if (Res.isInvalid()) + return true; + + Converted.push_back(Result); + break; + } + + case TemplateArgument::Declaration: + case TemplateArgument::Integral: + // We've already checked this template argument, so just copy + // it to the list of converted arguments. + Converted.push_back(Arg.getArgument()); + break; + + case TemplateArgument::Template: + case TemplateArgument::TemplateExpansion: + // We were given a template template argument. It may not be ill-formed; + // see below. + if (DependentTemplateName *DTN + = Arg.getArgument().getAsTemplateOrTemplatePattern() + .getAsDependentTemplateName()) { + // We have a template argument such as \c T::template X, which we + // parsed as a template template argument. However, since we now + // know that we need a non-type template argument, convert this + // template name into an expression. + + DeclarationNameInfo NameInfo(DTN->getIdentifier(), + Arg.getTemplateNameLoc()); + + CXXScopeSpec SS; + SS.Adopt(Arg.getTemplateQualifierLoc()); + // FIXME: the template-template arg was a DependentTemplateName, + // so it was provided with a template keyword. However, its source + // location is not stored in the template argument structure. + SourceLocation TemplateKWLoc; + ExprResult E = Owned(DependentScopeDeclRefExpr::Create(Context, + SS.getWithLocInContext(Context), + TemplateKWLoc, + NameInfo, 0)); + + // If we parsed the template argument as a pack expansion, create a + // pack expansion expression. + if (Arg.getArgument().getKind() == TemplateArgument::TemplateExpansion){ + E = ActOnPackExpansion(E.take(), Arg.getTemplateEllipsisLoc()); + if (E.isInvalid()) + return true; + } + + TemplateArgument Result; + E = CheckTemplateArgument(NTTP, NTTPType, E.take(), Result); + if (E.isInvalid()) + return true; + + Converted.push_back(Result); + break; + } + + // We have a template argument that actually does refer to a class + // template, alias template, or template template parameter, and + // therefore cannot be a non-type template argument. + Diag(Arg.getLocation(), diag::err_template_arg_must_be_expr) + << Arg.getSourceRange(); + + Diag(Param->getLocation(), diag::note_template_param_here); + return true; + + case TemplateArgument::Type: { + // We have a non-type template parameter but the template + // argument is a type. + + // C++ [temp.arg]p2: + // In a template-argument, an ambiguity between a type-id and + // an expression is resolved to a type-id, regardless of the + // form of the corresponding template-parameter. + // + // We warn specifically about this case, since it can be rather + // confusing for users. + QualType T = Arg.getArgument().getAsType(); + SourceRange SR = Arg.getSourceRange(); + if (T->isFunctionType()) + Diag(SR.getBegin(), diag::err_template_arg_nontype_ambig) << SR << T; + else + Diag(SR.getBegin(), diag::err_template_arg_must_be_expr) << SR; + Diag(Param->getLocation(), diag::note_template_param_here); + return true; + } + + case TemplateArgument::Pack: + llvm_unreachable("Caller must expand template argument packs"); + } + + return false; + } + + + // Check template template parameters. + TemplateTemplateParmDecl *TempParm = cast<TemplateTemplateParmDecl>(Param); + + // Substitute into the template parameter list of the template + // template parameter, since previously-supplied template arguments + // may appear within the template template parameter. + { + // Set up a template instantiation context. + LocalInstantiationScope Scope(*this); + InstantiatingTemplate Inst(*this, TemplateLoc, Template, + TempParm, Converted.data(), Converted.size(), + SourceRange(TemplateLoc, RAngleLoc)); + + TemplateArgumentList TemplateArgs(TemplateArgumentList::OnStack, + Converted.data(), Converted.size()); + TempParm = cast_or_null<TemplateTemplateParmDecl>( + SubstDecl(TempParm, CurContext, + MultiLevelTemplateArgumentList(TemplateArgs))); + if (!TempParm) + return true; + } + + switch (Arg.getArgument().getKind()) { + case TemplateArgument::Null: + llvm_unreachable("Should never see a NULL template argument here"); + + case TemplateArgument::Template: + case TemplateArgument::TemplateExpansion: + if (CheckTemplateArgument(TempParm, Arg)) + return true; + + Converted.push_back(Arg.getArgument()); + break; + + case TemplateArgument::Expression: + case TemplateArgument::Type: + // We have a template template parameter but the template + // argument does not refer to a template. + Diag(Arg.getLocation(), diag::err_template_arg_must_be_template) + << getLangOpts().CPlusPlus0x; + return true; + + case TemplateArgument::Declaration: + llvm_unreachable("Declaration argument with template template parameter"); + case TemplateArgument::Integral: + llvm_unreachable("Integral argument with template template parameter"); + + case TemplateArgument::Pack: + llvm_unreachable("Caller must expand template argument packs"); + } + + return false; +} + +/// \brief Diagnose an arity mismatch in the +static bool diagnoseArityMismatch(Sema &S, TemplateDecl *Template, + SourceLocation TemplateLoc, + TemplateArgumentListInfo &TemplateArgs) { + TemplateParameterList *Params = Template->getTemplateParameters(); + unsigned NumParams = Params->size(); + unsigned NumArgs = TemplateArgs.size(); + + SourceRange Range; + if (NumArgs > NumParams) + Range = SourceRange(TemplateArgs[NumParams].getLocation(), + TemplateArgs.getRAngleLoc()); + S.Diag(TemplateLoc, diag::err_template_arg_list_different_arity) + << (NumArgs > NumParams) + << (isa<ClassTemplateDecl>(Template)? 0 : + isa<FunctionTemplateDecl>(Template)? 1 : + isa<TemplateTemplateParmDecl>(Template)? 2 : 3) + << Template << Range; + S.Diag(Template->getLocation(), diag::note_template_decl_here) + << Params->getSourceRange(); + return true; +} + +/// \brief Check that the given template argument list is well-formed +/// for specializing the given template. +bool Sema::CheckTemplateArgumentList(TemplateDecl *Template, + SourceLocation TemplateLoc, + TemplateArgumentListInfo &TemplateArgs, + bool PartialTemplateArgs, + SmallVectorImpl<TemplateArgument> &Converted, + bool *ExpansionIntoFixedList) { + if (ExpansionIntoFixedList) + *ExpansionIntoFixedList = false; + + TemplateParameterList *Params = Template->getTemplateParameters(); + unsigned NumParams = Params->size(); + unsigned NumArgs = TemplateArgs.size(); + bool Invalid = false; + + SourceLocation RAngleLoc = TemplateArgs.getRAngleLoc(); + + bool HasParameterPack = + NumParams > 0 && Params->getParam(NumParams - 1)->isTemplateParameterPack(); + + // C++ [temp.arg]p1: + // [...] The type and form of each template-argument specified in + // a template-id shall match the type and form specified for the + // corresponding parameter declared by the template in its + // template-parameter-list. + bool isTemplateTemplateParameter = isa<TemplateTemplateParmDecl>(Template); + SmallVector<TemplateArgument, 2> ArgumentPack; + TemplateParameterList::iterator Param = Params->begin(), + ParamEnd = Params->end(); + unsigned ArgIdx = 0; + LocalInstantiationScope InstScope(*this, true); + bool SawPackExpansion = false; + while (Param != ParamEnd) { + if (ArgIdx < NumArgs) { + // If we have an expanded parameter pack, make sure we don't have too + // many arguments. + // FIXME: This really should fall out from the normal arity checking. + if (NonTypeTemplateParmDecl *NTTP + = dyn_cast<NonTypeTemplateParmDecl>(*Param)) { + if (NTTP->isExpandedParameterPack() && + ArgumentPack.size() >= NTTP->getNumExpansionTypes()) { + Diag(TemplateLoc, diag::err_template_arg_list_different_arity) + << true + << (isa<ClassTemplateDecl>(Template)? 0 : + isa<FunctionTemplateDecl>(Template)? 1 : + isa<TemplateTemplateParmDecl>(Template)? 2 : 3) + << Template; + Diag(Template->getLocation(), diag::note_template_decl_here) + << Params->getSourceRange(); + return true; + } + } + + // Check the template argument we were given. + if (CheckTemplateArgument(*Param, TemplateArgs[ArgIdx], Template, + TemplateLoc, RAngleLoc, + ArgumentPack.size(), Converted)) + return true; + + if ((*Param)->isTemplateParameterPack()) { + // The template parameter was a template parameter pack, so take the + // deduced argument and place it on the argument pack. Note that we + // stay on the same template parameter so that we can deduce more + // arguments. + ArgumentPack.push_back(Converted.back()); + Converted.pop_back(); + } else { + // Move to the next template parameter. + ++Param; + } + + // If this template argument is a pack expansion, record that fact + // and break out; we can't actually check any more. + if (TemplateArgs[ArgIdx].getArgument().isPackExpansion()) { + SawPackExpansion = true; + ++ArgIdx; + break; + } + + ++ArgIdx; + continue; + } + + // If we're checking a partial template argument list, we're done. + if (PartialTemplateArgs) { + if ((*Param)->isTemplateParameterPack() && !ArgumentPack.empty()) + Converted.push_back(TemplateArgument::CreatePackCopy(Context, + ArgumentPack.data(), + ArgumentPack.size())); + + return Invalid; + } + + // If we have a template parameter pack with no more corresponding + // arguments, just break out now and we'll fill in the argument pack below. + if ((*Param)->isTemplateParameterPack()) + break; + + // Check whether we have a default argument. + TemplateArgumentLoc Arg; + + // Retrieve the default template argument from the template + // parameter. For each kind of template parameter, we substitute the + // template arguments provided thus far and any "outer" template arguments + // (when the template parameter was part of a nested template) into + // the default argument. + if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(*Param)) { + if (!TTP->hasDefaultArgument()) + return diagnoseArityMismatch(*this, Template, TemplateLoc, + TemplateArgs); + + TypeSourceInfo *ArgType = SubstDefaultTemplateArgument(*this, + Template, + TemplateLoc, + RAngleLoc, + TTP, + Converted); + if (!ArgType) + return true; + + Arg = TemplateArgumentLoc(TemplateArgument(ArgType->getType()), + ArgType); + } else if (NonTypeTemplateParmDecl *NTTP + = dyn_cast<NonTypeTemplateParmDecl>(*Param)) { + if (!NTTP->hasDefaultArgument()) + return diagnoseArityMismatch(*this, Template, TemplateLoc, + TemplateArgs); + + ExprResult E = SubstDefaultTemplateArgument(*this, Template, + TemplateLoc, + RAngleLoc, + NTTP, + Converted); + if (E.isInvalid()) + return true; + + Expr *Ex = E.takeAs<Expr>(); + Arg = TemplateArgumentLoc(TemplateArgument(Ex), Ex); + } else { + TemplateTemplateParmDecl *TempParm + = cast<TemplateTemplateParmDecl>(*Param); + + if (!TempParm->hasDefaultArgument()) + return diagnoseArityMismatch(*this, Template, TemplateLoc, + TemplateArgs); + + NestedNameSpecifierLoc QualifierLoc; + TemplateName Name = SubstDefaultTemplateArgument(*this, Template, + TemplateLoc, + RAngleLoc, + TempParm, + Converted, + QualifierLoc); + if (Name.isNull()) + return true; + + Arg = TemplateArgumentLoc(TemplateArgument(Name), QualifierLoc, + TempParm->getDefaultArgument().getTemplateNameLoc()); + } + + // Introduce an instantiation record that describes where we are using + // the default template argument. + InstantiatingTemplate Instantiating(*this, RAngleLoc, Template, *Param, + Converted.data(), Converted.size(), + SourceRange(TemplateLoc, RAngleLoc)); + + // Check the default template argument. + if (CheckTemplateArgument(*Param, Arg, Template, TemplateLoc, + RAngleLoc, 0, Converted)) + return true; + + // Core issue 150 (assumed resolution): if this is a template template + // parameter, keep track of the default template arguments from the + // template definition. + if (isTemplateTemplateParameter) + TemplateArgs.addArgument(Arg); + + // Move to the next template parameter and argument. + ++Param; + ++ArgIdx; + } + + // If we saw a pack expansion, then directly convert the remaining arguments, + // because we don't know what parameters they'll match up with. + if (SawPackExpansion) { + bool AddToArgumentPack + = Param != ParamEnd && (*Param)->isTemplateParameterPack(); + while (ArgIdx < NumArgs) { + if (AddToArgumentPack) + ArgumentPack.push_back(TemplateArgs[ArgIdx].getArgument()); + else + Converted.push_back(TemplateArgs[ArgIdx].getArgument()); + ++ArgIdx; + } + + // Push the argument pack onto the list of converted arguments. + if (AddToArgumentPack) { + if (ArgumentPack.empty()) + Converted.push_back(TemplateArgument(0, 0)); + else { + Converted.push_back( + TemplateArgument::CreatePackCopy(Context, + ArgumentPack.data(), + ArgumentPack.size())); + ArgumentPack.clear(); + } + } else if (ExpansionIntoFixedList) { + // We have expanded a pack into a fixed list. + *ExpansionIntoFixedList = true; + } + + return Invalid; + } + + // If we have any leftover arguments, then there were too many arguments. + // Complain and fail. + if (ArgIdx < NumArgs) + return diagnoseArityMismatch(*this, Template, TemplateLoc, TemplateArgs); + + // If we have an expanded parameter pack, make sure we don't have too + // many arguments. + // FIXME: This really should fall out from the normal arity checking. + if (Param != ParamEnd) { + if (NonTypeTemplateParmDecl *NTTP + = dyn_cast<NonTypeTemplateParmDecl>(*Param)) { + if (NTTP->isExpandedParameterPack() && + ArgumentPack.size() < NTTP->getNumExpansionTypes()) { + Diag(TemplateLoc, diag::err_template_arg_list_different_arity) + << false + << (isa<ClassTemplateDecl>(Template)? 0 : + isa<FunctionTemplateDecl>(Template)? 1 : + isa<TemplateTemplateParmDecl>(Template)? 2 : 3) + << Template; + Diag(Template->getLocation(), diag::note_template_decl_here) + << Params->getSourceRange(); + return true; + } + } + } + + // Form argument packs for each of the parameter packs remaining. + while (Param != ParamEnd) { + // If we're checking a partial list of template arguments, don't fill + // in arguments for non-template parameter packs. + if ((*Param)->isTemplateParameterPack()) { + if (!HasParameterPack) + return true; + if (ArgumentPack.empty()) + Converted.push_back(TemplateArgument(0, 0)); + else { + Converted.push_back(TemplateArgument::CreatePackCopy(Context, + ArgumentPack.data(), + ArgumentPack.size())); + ArgumentPack.clear(); + } + } else if (!PartialTemplateArgs) + return diagnoseArityMismatch(*this, Template, TemplateLoc, TemplateArgs); + + ++Param; + } + + return Invalid; +} + +namespace { + class UnnamedLocalNoLinkageFinder + : public TypeVisitor<UnnamedLocalNoLinkageFinder, bool> + { + Sema &S; + SourceRange SR; + + typedef TypeVisitor<UnnamedLocalNoLinkageFinder, bool> inherited; + + public: + UnnamedLocalNoLinkageFinder(Sema &S, SourceRange SR) : S(S), SR(SR) { } + + bool Visit(QualType T) { + return inherited::Visit(T.getTypePtr()); + } + +#define TYPE(Class, Parent) \ + bool Visit##Class##Type(const Class##Type *); +#define ABSTRACT_TYPE(Class, Parent) \ + bool Visit##Class##Type(const Class##Type *) { return false; } +#define NON_CANONICAL_TYPE(Class, Parent) \ + bool Visit##Class##Type(const Class##Type *) { return false; } +#include "clang/AST/TypeNodes.def" + + bool VisitTagDecl(const TagDecl *Tag); + bool VisitNestedNameSpecifier(NestedNameSpecifier *NNS); + }; +} + +bool UnnamedLocalNoLinkageFinder::VisitBuiltinType(const BuiltinType*) { + return false; +} + +bool UnnamedLocalNoLinkageFinder::VisitComplexType(const ComplexType* T) { + return Visit(T->getElementType()); +} + +bool UnnamedLocalNoLinkageFinder::VisitPointerType(const PointerType* T) { + return Visit(T->getPointeeType()); +} + +bool UnnamedLocalNoLinkageFinder::VisitBlockPointerType( + const BlockPointerType* T) { + return Visit(T->getPointeeType()); +} + +bool UnnamedLocalNoLinkageFinder::VisitLValueReferenceType( + const LValueReferenceType* T) { + return Visit(T->getPointeeType()); +} + +bool UnnamedLocalNoLinkageFinder::VisitRValueReferenceType( + const RValueReferenceType* T) { + return Visit(T->getPointeeType()); +} + +bool UnnamedLocalNoLinkageFinder::VisitMemberPointerType( + const MemberPointerType* T) { + return Visit(T->getPointeeType()) || Visit(QualType(T->getClass(), 0)); +} + +bool UnnamedLocalNoLinkageFinder::VisitConstantArrayType( + const ConstantArrayType* T) { + return Visit(T->getElementType()); +} + +bool UnnamedLocalNoLinkageFinder::VisitIncompleteArrayType( + const IncompleteArrayType* T) { + return Visit(T->getElementType()); +} + +bool UnnamedLocalNoLinkageFinder::VisitVariableArrayType( + const VariableArrayType* T) { + return Visit(T->getElementType()); +} + +bool UnnamedLocalNoLinkageFinder::VisitDependentSizedArrayType( + const DependentSizedArrayType* T) { + return Visit(T->getElementType()); +} + +bool UnnamedLocalNoLinkageFinder::VisitDependentSizedExtVectorType( + const DependentSizedExtVectorType* T) { + return Visit(T->getElementType()); +} + +bool UnnamedLocalNoLinkageFinder::VisitVectorType(const VectorType* T) { + return Visit(T->getElementType()); +} + +bool UnnamedLocalNoLinkageFinder::VisitExtVectorType(const ExtVectorType* T) { + return Visit(T->getElementType()); +} + +bool UnnamedLocalNoLinkageFinder::VisitFunctionProtoType( + const FunctionProtoType* T) { + for (FunctionProtoType::arg_type_iterator A = T->arg_type_begin(), + AEnd = T->arg_type_end(); + A != AEnd; ++A) { + if (Visit(*A)) + return true; + } + + return Visit(T->getResultType()); +} + +bool UnnamedLocalNoLinkageFinder::VisitFunctionNoProtoType( + const FunctionNoProtoType* T) { + return Visit(T->getResultType()); +} + +bool UnnamedLocalNoLinkageFinder::VisitUnresolvedUsingType( + const UnresolvedUsingType*) { + return false; +} + +bool UnnamedLocalNoLinkageFinder::VisitTypeOfExprType(const TypeOfExprType*) { + return false; +} + +bool UnnamedLocalNoLinkageFinder::VisitTypeOfType(const TypeOfType* T) { + return Visit(T->getUnderlyingType()); +} + +bool UnnamedLocalNoLinkageFinder::VisitDecltypeType(const DecltypeType*) { + return false; +} + +bool UnnamedLocalNoLinkageFinder::VisitUnaryTransformType( + const UnaryTransformType*) { + return false; +} + +bool UnnamedLocalNoLinkageFinder::VisitAutoType(const AutoType *T) { + return Visit(T->getDeducedType()); +} + +bool UnnamedLocalNoLinkageFinder::VisitRecordType(const RecordType* T) { + return VisitTagDecl(T->getDecl()); +} + +bool UnnamedLocalNoLinkageFinder::VisitEnumType(const EnumType* T) { + return VisitTagDecl(T->getDecl()); +} + +bool UnnamedLocalNoLinkageFinder::VisitTemplateTypeParmType( + const TemplateTypeParmType*) { + return false; +} + +bool UnnamedLocalNoLinkageFinder::VisitSubstTemplateTypeParmPackType( + const SubstTemplateTypeParmPackType *) { + return false; +} + +bool UnnamedLocalNoLinkageFinder::VisitTemplateSpecializationType( + const TemplateSpecializationType*) { + return false; +} + +bool UnnamedLocalNoLinkageFinder::VisitInjectedClassNameType( + const InjectedClassNameType* T) { + return VisitTagDecl(T->getDecl()); +} + +bool UnnamedLocalNoLinkageFinder::VisitDependentNameType( + const DependentNameType* T) { + return VisitNestedNameSpecifier(T->getQualifier()); +} + +bool UnnamedLocalNoLinkageFinder::VisitDependentTemplateSpecializationType( + const DependentTemplateSpecializationType* T) { + return VisitNestedNameSpecifier(T->getQualifier()); +} + +bool UnnamedLocalNoLinkageFinder::VisitPackExpansionType( + const PackExpansionType* T) { + return Visit(T->getPattern()); +} + +bool UnnamedLocalNoLinkageFinder::VisitObjCObjectType(const ObjCObjectType *) { + return false; +} + +bool UnnamedLocalNoLinkageFinder::VisitObjCInterfaceType( + const ObjCInterfaceType *) { + return false; +} + +bool UnnamedLocalNoLinkageFinder::VisitObjCObjectPointerType( + const ObjCObjectPointerType *) { + return false; +} + +bool UnnamedLocalNoLinkageFinder::VisitAtomicType(const AtomicType* T) { + return Visit(T->getValueType()); +} + +bool UnnamedLocalNoLinkageFinder::VisitTagDecl(const TagDecl *Tag) { + if (Tag->getDeclContext()->isFunctionOrMethod()) { + S.Diag(SR.getBegin(), + S.getLangOpts().CPlusPlus0x ? + diag::warn_cxx98_compat_template_arg_local_type : + diag::ext_template_arg_local_type) + << S.Context.getTypeDeclType(Tag) << SR; + return true; + } + + if (!Tag->getDeclName() && !Tag->getTypedefNameForAnonDecl()) { + S.Diag(SR.getBegin(), + S.getLangOpts().CPlusPlus0x ? + diag::warn_cxx98_compat_template_arg_unnamed_type : + diag::ext_template_arg_unnamed_type) << SR; + S.Diag(Tag->getLocation(), diag::note_template_unnamed_type_here); + return true; + } + + return false; +} + +bool UnnamedLocalNoLinkageFinder::VisitNestedNameSpecifier( + NestedNameSpecifier *NNS) { + if (NNS->getPrefix() && VisitNestedNameSpecifier(NNS->getPrefix())) + return true; + + switch (NNS->getKind()) { + case NestedNameSpecifier::Identifier: + case NestedNameSpecifier::Namespace: + case NestedNameSpecifier::NamespaceAlias: + case NestedNameSpecifier::Global: + return false; + + case NestedNameSpecifier::TypeSpec: + case NestedNameSpecifier::TypeSpecWithTemplate: + return Visit(QualType(NNS->getAsType(), 0)); + } + llvm_unreachable("Invalid NestedNameSpecifier::Kind!"); +} + + +/// \brief Check a template argument against its corresponding +/// template type parameter. +/// +/// This routine implements the semantics of C++ [temp.arg.type]. It +/// returns true if an error occurred, and false otherwise. +bool Sema::CheckTemplateArgument(TemplateTypeParmDecl *Param, + TypeSourceInfo *ArgInfo) { + assert(ArgInfo && "invalid TypeSourceInfo"); + QualType Arg = ArgInfo->getType(); + SourceRange SR = ArgInfo->getTypeLoc().getSourceRange(); + + if (Arg->isVariablyModifiedType()) { + return Diag(SR.getBegin(), diag::err_variably_modified_template_arg) << Arg; + } else if (Context.hasSameUnqualifiedType(Arg, Context.OverloadTy)) { + return Diag(SR.getBegin(), diag::err_template_arg_overload_type) << SR; + } + + // C++03 [temp.arg.type]p2: + // A local type, a type with no linkage, an unnamed type or a type + // compounded from any of these types shall not be used as a + // template-argument for a template type-parameter. + // + // C++11 allows these, and even in C++03 we allow them as an extension with + // a warning. + if (LangOpts.CPlusPlus0x ? + Diags.getDiagnosticLevel(diag::warn_cxx98_compat_template_arg_unnamed_type, + SR.getBegin()) != DiagnosticsEngine::Ignored || + Diags.getDiagnosticLevel(diag::warn_cxx98_compat_template_arg_local_type, + SR.getBegin()) != DiagnosticsEngine::Ignored : + Arg->hasUnnamedOrLocalType()) { + UnnamedLocalNoLinkageFinder Finder(*this, SR); + (void)Finder.Visit(Context.getCanonicalType(Arg)); + } + + return false; +} + +enum NullPointerValueKind { + NPV_NotNullPointer, + NPV_NullPointer, + NPV_Error +}; + +/// \brief Determine whether the given template argument is a null pointer +/// value of the appropriate type. +static NullPointerValueKind +isNullPointerValueTemplateArgument(Sema &S, NonTypeTemplateParmDecl *Param, + QualType ParamType, Expr *Arg) { + if (Arg->isValueDependent() || Arg->isTypeDependent()) + return NPV_NotNullPointer; + + if (!S.getLangOpts().CPlusPlus0x) + return NPV_NotNullPointer; + + // Determine whether we have a constant expression. + ExprResult ArgRV = S.DefaultFunctionArrayConversion(Arg); + if (ArgRV.isInvalid()) + return NPV_Error; + Arg = ArgRV.take(); + + Expr::EvalResult EvalResult; + llvm::SmallVector<PartialDiagnosticAt, 8> Notes; + EvalResult.Diag = &Notes; + if (!Arg->EvaluateAsRValue(EvalResult, S.Context) || + EvalResult.HasSideEffects) { + SourceLocation DiagLoc = Arg->getExprLoc(); + + // If our only note is the usual "invalid subexpression" note, just point + // the caret at its location rather than producing an essentially + // redundant note. + if (Notes.size() == 1 && Notes[0].second.getDiagID() == + diag::note_invalid_subexpr_in_const_expr) { + DiagLoc = Notes[0].first; + Notes.clear(); + } + + S.Diag(DiagLoc, diag::err_template_arg_not_address_constant) + << Arg->getType() << Arg->getSourceRange(); + for (unsigned I = 0, N = Notes.size(); I != N; ++I) + S.Diag(Notes[I].first, Notes[I].second); + + S.Diag(Param->getLocation(), diag::note_template_param_here); + return NPV_Error; + } + + // C++11 [temp.arg.nontype]p1: + // - an address constant expression of type std::nullptr_t + if (Arg->getType()->isNullPtrType()) + return NPV_NullPointer; + + // - a constant expression that evaluates to a null pointer value (4.10); or + // - a constant expression that evaluates to a null member pointer value + // (4.11); or + if ((EvalResult.Val.isLValue() && !EvalResult.Val.getLValueBase()) || + (EvalResult.Val.isMemberPointer() && + !EvalResult.Val.getMemberPointerDecl())) { + // If our expression has an appropriate type, we've succeeded. + bool ObjCLifetimeConversion; + if (S.Context.hasSameUnqualifiedType(Arg->getType(), ParamType) || + S.IsQualificationConversion(Arg->getType(), ParamType, false, + ObjCLifetimeConversion)) + return NPV_NullPointer; + + // The types didn't match, but we know we got a null pointer; complain, + // then recover as if the types were correct. + S.Diag(Arg->getExprLoc(), diag::err_template_arg_wrongtype_null_constant) + << Arg->getType() << ParamType << Arg->getSourceRange(); + S.Diag(Param->getLocation(), diag::note_template_param_here); + return NPV_NullPointer; + } + + // If we don't have a null pointer value, but we do have a NULL pointer + // constant, suggest a cast to the appropriate type. + if (Arg->isNullPointerConstant(S.Context, Expr::NPC_NeverValueDependent)) { + std::string Code = "static_cast<" + ParamType.getAsString() + ">("; + S.Diag(Arg->getExprLoc(), diag::err_template_arg_untyped_null_constant) + << ParamType + << FixItHint::CreateInsertion(Arg->getLocStart(), Code) + << FixItHint::CreateInsertion(S.PP.getLocForEndOfToken(Arg->getLocEnd()), + ")"); + S.Diag(Param->getLocation(), diag::note_template_param_here); + return NPV_NullPointer; + } + + // FIXME: If we ever want to support general, address-constant expressions + // as non-type template arguments, we should return the ExprResult here to + // be interpreted by the caller. + return NPV_NotNullPointer; +} + +/// \brief Checks whether the given template argument is the address +/// of an object or function according to C++ [temp.arg.nontype]p1. +static bool +CheckTemplateArgumentAddressOfObjectOrFunction(Sema &S, + NonTypeTemplateParmDecl *Param, + QualType ParamType, + Expr *ArgIn, + TemplateArgument &Converted) { + bool Invalid = false; + Expr *Arg = ArgIn; + QualType ArgType = Arg->getType(); + + // If our parameter has pointer type, check for a null template value. + if (ParamType->isPointerType() || ParamType->isNullPtrType()) { + switch (isNullPointerValueTemplateArgument(S, Param, ParamType, Arg)) { + case NPV_NullPointer: + Converted = TemplateArgument((Decl *)0); + return false; + + case NPV_Error: + return true; + + case NPV_NotNullPointer: + break; + } + } + + // See through any implicit casts we added to fix the type. + Arg = Arg->IgnoreImpCasts(); + + // C++ [temp.arg.nontype]p1: + // + // A template-argument for a non-type, non-template + // template-parameter shall be one of: [...] + // + // -- the address of an object or function with external + // linkage, including function templates and function + // template-ids but excluding non-static class members, + // expressed as & id-expression where the & is optional if + // the name refers to a function or array, or if the + // corresponding template-parameter is a reference; or + + // In C++98/03 mode, give an extension warning on any extra parentheses. + // See http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_defects.html#773 + bool ExtraParens = false; + while (ParenExpr *Parens = dyn_cast<ParenExpr>(Arg)) { + if (!Invalid && !ExtraParens) { + S.Diag(Arg->getLocStart(), + S.getLangOpts().CPlusPlus0x ? + diag::warn_cxx98_compat_template_arg_extra_parens : + diag::ext_template_arg_extra_parens) + << Arg->getSourceRange(); + ExtraParens = true; + } + + Arg = Parens->getSubExpr(); + } + + while (SubstNonTypeTemplateParmExpr *subst = + dyn_cast<SubstNonTypeTemplateParmExpr>(Arg)) + Arg = subst->getReplacement()->IgnoreImpCasts(); + + bool AddressTaken = false; + SourceLocation AddrOpLoc; + if (UnaryOperator *UnOp = dyn_cast<UnaryOperator>(Arg)) { + if (UnOp->getOpcode() == UO_AddrOf) { + Arg = UnOp->getSubExpr(); + AddressTaken = true; + AddrOpLoc = UnOp->getOperatorLoc(); + } + } + + if (S.getLangOpts().MicrosoftExt && isa<CXXUuidofExpr>(Arg)) { + Converted = TemplateArgument(ArgIn); + return false; + } + + while (SubstNonTypeTemplateParmExpr *subst = + dyn_cast<SubstNonTypeTemplateParmExpr>(Arg)) + Arg = subst->getReplacement()->IgnoreImpCasts(); + + // Stop checking the precise nature of the argument if it is value dependent, + // it should be checked when instantiated. + if (Arg->isValueDependent()) { + Converted = TemplateArgument(ArgIn); + return false; + } + + DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Arg); + if (!DRE) { + S.Diag(Arg->getLocStart(), diag::err_template_arg_not_decl_ref) + << Arg->getSourceRange(); + S.Diag(Param->getLocation(), diag::note_template_param_here); + return true; + } + + if (!isa<ValueDecl>(DRE->getDecl())) { + S.Diag(Arg->getLocStart(), + diag::err_template_arg_not_object_or_func_form) + << Arg->getSourceRange(); + S.Diag(Param->getLocation(), diag::note_template_param_here); + return true; + } + + NamedDecl *Entity = DRE->getDecl(); + + // Cannot refer to non-static data members + if (FieldDecl *Field = dyn_cast<FieldDecl>(Entity)) { + S.Diag(Arg->getLocStart(), diag::err_template_arg_field) + << Field << Arg->getSourceRange(); + S.Diag(Param->getLocation(), diag::note_template_param_here); + return true; + } + + // Cannot refer to non-static member functions + if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Entity)) { + if (!Method->isStatic()) { + S.Diag(Arg->getLocStart(), diag::err_template_arg_method) + << Method << Arg->getSourceRange(); + S.Diag(Param->getLocation(), diag::note_template_param_here); + return true; + } + } + + FunctionDecl *Func = dyn_cast<FunctionDecl>(Entity); + VarDecl *Var = dyn_cast<VarDecl>(Entity); + + // A non-type template argument must refer to an object or function. + if (!Func && !Var) { + // We found something, but we don't know specifically what it is. + S.Diag(Arg->getLocStart(), diag::err_template_arg_not_object_or_func) + << Arg->getSourceRange(); + S.Diag(DRE->getDecl()->getLocation(), diag::note_template_arg_refers_here); + return true; + } + + // Address / reference template args must have external linkage in C++98. + if (Entity->getLinkage() == InternalLinkage) { + S.Diag(Arg->getLocStart(), S.getLangOpts().CPlusPlus0x ? + diag::warn_cxx98_compat_template_arg_object_internal : + diag::ext_template_arg_object_internal) + << !Func << Entity << Arg->getSourceRange(); + S.Diag(Entity->getLocation(), diag::note_template_arg_internal_object) + << !Func; + } else if (Entity->getLinkage() == NoLinkage) { + S.Diag(Arg->getLocStart(), diag::err_template_arg_object_no_linkage) + << !Func << Entity << Arg->getSourceRange(); + S.Diag(Entity->getLocation(), diag::note_template_arg_internal_object) + << !Func; + return true; + } + + if (Func) { + // If the template parameter has pointer type, the function decays. + if (ParamType->isPointerType() && !AddressTaken) + ArgType = S.Context.getPointerType(Func->getType()); + else if (AddressTaken && ParamType->isReferenceType()) { + // If we originally had an address-of operator, but the + // parameter has reference type, complain and (if things look + // like they will work) drop the address-of operator. + if (!S.Context.hasSameUnqualifiedType(Func->getType(), + ParamType.getNonReferenceType())) { + S.Diag(AddrOpLoc, diag::err_template_arg_address_of_non_pointer) + << ParamType; + S.Diag(Param->getLocation(), diag::note_template_param_here); + return true; + } + + S.Diag(AddrOpLoc, diag::err_template_arg_address_of_non_pointer) + << ParamType + << FixItHint::CreateRemoval(AddrOpLoc); + S.Diag(Param->getLocation(), diag::note_template_param_here); + + ArgType = Func->getType(); + } + } else { + // A value of reference type is not an object. + if (Var->getType()->isReferenceType()) { + S.Diag(Arg->getLocStart(), + diag::err_template_arg_reference_var) + << Var->getType() << Arg->getSourceRange(); + S.Diag(Param->getLocation(), diag::note_template_param_here); + return true; + } + + // A template argument must have static storage duration. + // FIXME: Ensure this works for thread_local as well as __thread. + if (Var->isThreadSpecified()) { + S.Diag(Arg->getLocStart(), diag::err_template_arg_thread_local) + << Arg->getSourceRange(); + S.Diag(Var->getLocation(), diag::note_template_arg_refers_here); + return true; + } + + // If the template parameter has pointer type, we must have taken + // the address of this object. + if (ParamType->isReferenceType()) { + if (AddressTaken) { + // If we originally had an address-of operator, but the + // parameter has reference type, complain and (if things look + // like they will work) drop the address-of operator. + if (!S.Context.hasSameUnqualifiedType(Var->getType(), + ParamType.getNonReferenceType())) { + S.Diag(AddrOpLoc, diag::err_template_arg_address_of_non_pointer) + << ParamType; + S.Diag(Param->getLocation(), diag::note_template_param_here); + return true; + } + + S.Diag(AddrOpLoc, diag::err_template_arg_address_of_non_pointer) + << ParamType + << FixItHint::CreateRemoval(AddrOpLoc); + S.Diag(Param->getLocation(), diag::note_template_param_here); + + ArgType = Var->getType(); + } + } else if (!AddressTaken && ParamType->isPointerType()) { + if (Var->getType()->isArrayType()) { + // Array-to-pointer decay. + ArgType = S.Context.getArrayDecayedType(Var->getType()); + } else { + // If the template parameter has pointer type but the address of + // this object was not taken, complain and (possibly) recover by + // taking the address of the entity. + ArgType = S.Context.getPointerType(Var->getType()); + if (!S.Context.hasSameUnqualifiedType(ArgType, ParamType)) { + S.Diag(Arg->getLocStart(), diag::err_template_arg_not_address_of) + << ParamType; + S.Diag(Param->getLocation(), diag::note_template_param_here); + return true; + } + + S.Diag(Arg->getLocStart(), diag::err_template_arg_not_address_of) + << ParamType + << FixItHint::CreateInsertion(Arg->getLocStart(), "&"); + + S.Diag(Param->getLocation(), diag::note_template_param_here); + } + } + } + + bool ObjCLifetimeConversion; + if (ParamType->isPointerType() && + !ParamType->getAs<PointerType>()->getPointeeType()->isFunctionType() && + S.IsQualificationConversion(ArgType, ParamType, false, + ObjCLifetimeConversion)) { + // For pointer-to-object types, qualification conversions are + // permitted. + } else { + if (const ReferenceType *ParamRef = ParamType->getAs<ReferenceType>()) { + if (!ParamRef->getPointeeType()->isFunctionType()) { + // C++ [temp.arg.nontype]p5b3: + // For a non-type template-parameter of type reference to + // object, no conversions apply. The type referred to by the + // reference may be more cv-qualified than the (otherwise + // identical) type of the template- argument. The + // template-parameter is bound directly to the + // template-argument, which shall be an lvalue. + + // FIXME: Other qualifiers? + unsigned ParamQuals = ParamRef->getPointeeType().getCVRQualifiers(); + unsigned ArgQuals = ArgType.getCVRQualifiers(); + + if ((ParamQuals | ArgQuals) != ParamQuals) { + S.Diag(Arg->getLocStart(), + diag::err_template_arg_ref_bind_ignores_quals) + << ParamType << Arg->getType() + << Arg->getSourceRange(); + S.Diag(Param->getLocation(), diag::note_template_param_here); + return true; + } + } + } + + // At this point, the template argument refers to an object or + // function with external linkage. We now need to check whether the + // argument and parameter types are compatible. + if (!S.Context.hasSameUnqualifiedType(ArgType, + ParamType.getNonReferenceType())) { + // We can't perform this conversion or binding. + if (ParamType->isReferenceType()) + S.Diag(Arg->getLocStart(), diag::err_template_arg_no_ref_bind) + << ParamType << ArgIn->getType() << Arg->getSourceRange(); + else + S.Diag(Arg->getLocStart(), diag::err_template_arg_not_convertible) + << ArgIn->getType() << ParamType << Arg->getSourceRange(); + S.Diag(Param->getLocation(), diag::note_template_param_here); + return true; + } + } + + // Create the template argument. + Converted = TemplateArgument(Entity->getCanonicalDecl()); + S.MarkAnyDeclReferenced(Arg->getLocStart(), Entity); + return false; +} + +/// \brief Checks whether the given template argument is a pointer to +/// member constant according to C++ [temp.arg.nontype]p1. +static bool CheckTemplateArgumentPointerToMember(Sema &S, + NonTypeTemplateParmDecl *Param, + QualType ParamType, + Expr *&ResultArg, + TemplateArgument &Converted) { + bool Invalid = false; + + // Check for a null pointer value. + Expr *Arg = ResultArg; + switch (isNullPointerValueTemplateArgument(S, Param, ParamType, Arg)) { + case NPV_Error: + return true; + case NPV_NullPointer: + Converted = TemplateArgument((Decl *)0); + return false; + case NPV_NotNullPointer: + break; + } + + bool ObjCLifetimeConversion; + if (S.IsQualificationConversion(Arg->getType(), + ParamType.getNonReferenceType(), + false, ObjCLifetimeConversion)) { + Arg = S.ImpCastExprToType(Arg, ParamType, CK_NoOp, + Arg->getValueKind()).take(); + ResultArg = Arg; + } else if (!S.Context.hasSameUnqualifiedType(Arg->getType(), + ParamType.getNonReferenceType())) { + // We can't perform this conversion. + S.Diag(Arg->getLocStart(), diag::err_template_arg_not_convertible) + << Arg->getType() << ParamType << Arg->getSourceRange(); + S.Diag(Param->getLocation(), diag::note_template_param_here); + return true; + } + + // See through any implicit casts we added to fix the type. + while (ImplicitCastExpr *Cast = dyn_cast<ImplicitCastExpr>(Arg)) + Arg = Cast->getSubExpr(); + + // C++ [temp.arg.nontype]p1: + // + // A template-argument for a non-type, non-template + // template-parameter shall be one of: [...] + // + // -- a pointer to member expressed as described in 5.3.1. + DeclRefExpr *DRE = 0; + + // In C++98/03 mode, give an extension warning on any extra parentheses. + // See http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_defects.html#773 + bool ExtraParens = false; + while (ParenExpr *Parens = dyn_cast<ParenExpr>(Arg)) { + if (!Invalid && !ExtraParens) { + S.Diag(Arg->getLocStart(), + S.getLangOpts().CPlusPlus0x ? + diag::warn_cxx98_compat_template_arg_extra_parens : + diag::ext_template_arg_extra_parens) + << Arg->getSourceRange(); + ExtraParens = true; + } + + Arg = Parens->getSubExpr(); + } + + while (SubstNonTypeTemplateParmExpr *subst = + dyn_cast<SubstNonTypeTemplateParmExpr>(Arg)) + Arg = subst->getReplacement()->IgnoreImpCasts(); + + // A pointer-to-member constant written &Class::member. + if (UnaryOperator *UnOp = dyn_cast<UnaryOperator>(Arg)) { + if (UnOp->getOpcode() == UO_AddrOf) { + DRE = dyn_cast<DeclRefExpr>(UnOp->getSubExpr()); + if (DRE && !DRE->getQualifier()) + DRE = 0; + } + } + // A constant of pointer-to-member type. + else if ((DRE = dyn_cast<DeclRefExpr>(Arg))) { + if (ValueDecl *VD = dyn_cast<ValueDecl>(DRE->getDecl())) { + if (VD->getType()->isMemberPointerType()) { + if (isa<NonTypeTemplateParmDecl>(VD) || + (isa<VarDecl>(VD) && + S.Context.getCanonicalType(VD->getType()).isConstQualified())) { + if (Arg->isTypeDependent() || Arg->isValueDependent()) + Converted = TemplateArgument(Arg); + else + Converted = TemplateArgument(VD->getCanonicalDecl()); + return Invalid; + } + } + } + + DRE = 0; + } + + if (!DRE) + return S.Diag(Arg->getLocStart(), + diag::err_template_arg_not_pointer_to_member_form) + << Arg->getSourceRange(); + + if (isa<FieldDecl>(DRE->getDecl()) || isa<CXXMethodDecl>(DRE->getDecl())) { + assert((isa<FieldDecl>(DRE->getDecl()) || + !cast<CXXMethodDecl>(DRE->getDecl())->isStatic()) && + "Only non-static member pointers can make it here"); + + // Okay: this is the address of a non-static member, and therefore + // a member pointer constant. + if (Arg->isTypeDependent() || Arg->isValueDependent()) + Converted = TemplateArgument(Arg); + else + Converted = TemplateArgument(DRE->getDecl()->getCanonicalDecl()); + return Invalid; + } + + // We found something else, but we don't know specifically what it is. + S.Diag(Arg->getLocStart(), + diag::err_template_arg_not_pointer_to_member_form) + << Arg->getSourceRange(); + S.Diag(DRE->getDecl()->getLocation(), diag::note_template_arg_refers_here); + return true; +} + +/// \brief Check a template argument against its corresponding +/// non-type template parameter. +/// +/// This routine implements the semantics of C++ [temp.arg.nontype]. +/// If an error occurred, it returns ExprError(); otherwise, it +/// returns the converted template argument. \p +/// InstantiatedParamType is the type of the non-type template +/// parameter after it has been instantiated. +ExprResult Sema::CheckTemplateArgument(NonTypeTemplateParmDecl *Param, + QualType InstantiatedParamType, Expr *Arg, + TemplateArgument &Converted, + CheckTemplateArgumentKind CTAK) { + SourceLocation StartLoc = Arg->getLocStart(); + + // If either the parameter has a dependent type or the argument is + // type-dependent, there's nothing we can check now. + if (InstantiatedParamType->isDependentType() || Arg->isTypeDependent()) { + // FIXME: Produce a cloned, canonical expression? + Converted = TemplateArgument(Arg); + return Owned(Arg); + } + + // C++ [temp.arg.nontype]p5: + // The following conversions are performed on each expression used + // as a non-type template-argument. If a non-type + // template-argument cannot be converted to the type of the + // corresponding template-parameter then the program is + // ill-formed. + QualType ParamType = InstantiatedParamType; + if (ParamType->isIntegralOrEnumerationType()) { + // C++11: + // -- for a non-type template-parameter of integral or + // enumeration type, conversions permitted in a converted + // constant expression are applied. + // + // C++98: + // -- for a non-type template-parameter of integral or + // enumeration type, integral promotions (4.5) and integral + // conversions (4.7) are applied. + + if (CTAK == CTAK_Deduced && + !Context.hasSameUnqualifiedType(ParamType, Arg->getType())) { + // C++ [temp.deduct.type]p17: + // If, in the declaration of a function template with a non-type + // template-parameter, the non-type template-parameter is used + // in an expression in the function parameter-list and, if the + // corresponding template-argument is deduced, the + // template-argument type shall match the type of the + // template-parameter exactly, except that a template-argument + // deduced from an array bound may be of any integral type. + Diag(StartLoc, diag::err_deduced_non_type_template_arg_type_mismatch) + << Arg->getType().getUnqualifiedType() + << ParamType.getUnqualifiedType(); + Diag(Param->getLocation(), diag::note_template_param_here); + return ExprError(); + } + + if (getLangOpts().CPlusPlus0x) { + // We can't check arbitrary value-dependent arguments. + // FIXME: If there's no viable conversion to the template parameter type, + // we should be able to diagnose that prior to instantiation. + if (Arg->isValueDependent()) { + Converted = TemplateArgument(Arg); + return Owned(Arg); + } + + // C++ [temp.arg.nontype]p1: + // A template-argument for a non-type, non-template template-parameter + // shall be one of: + // + // -- for a non-type template-parameter of integral or enumeration + // type, a converted constant expression of the type of the + // template-parameter; or + llvm::APSInt Value; + ExprResult ArgResult = + CheckConvertedConstantExpression(Arg, ParamType, Value, + CCEK_TemplateArg); + if (ArgResult.isInvalid()) + return ExprError(); + + // Widen the argument value to sizeof(parameter type). This is almost + // always a no-op, except when the parameter type is bool. In + // that case, this may extend the argument from 1 bit to 8 bits. + QualType IntegerType = ParamType; + if (const EnumType *Enum = IntegerType->getAs<EnumType>()) + IntegerType = Enum->getDecl()->getIntegerType(); + Value = Value.extOrTrunc(Context.getTypeSize(IntegerType)); + + Converted = TemplateArgument(Value, Context.getCanonicalType(ParamType)); + return ArgResult; + } + + ExprResult ArgResult = DefaultLvalueConversion(Arg); + if (ArgResult.isInvalid()) + return ExprError(); + Arg = ArgResult.take(); + + QualType ArgType = Arg->getType(); + + // C++ [temp.arg.nontype]p1: + // A template-argument for a non-type, non-template + // template-parameter shall be one of: + // + // -- an integral constant-expression of integral or enumeration + // type; or + // -- the name of a non-type template-parameter; or + SourceLocation NonConstantLoc; + llvm::APSInt Value; + if (!ArgType->isIntegralOrEnumerationType()) { + Diag(Arg->getLocStart(), + diag::err_template_arg_not_integral_or_enumeral) + << ArgType << Arg->getSourceRange(); + Diag(Param->getLocation(), diag::note_template_param_here); + return ExprError(); + } else if (!Arg->isValueDependent()) { + Arg = VerifyIntegerConstantExpression(Arg, &Value, + PDiag(diag::err_template_arg_not_ice) << ArgType, false).take(); + if (!Arg) + return ExprError(); + } + + // From here on out, all we care about are the unqualified forms + // of the parameter and argument types. + ParamType = ParamType.getUnqualifiedType(); + ArgType = ArgType.getUnqualifiedType(); + + // Try to convert the argument to the parameter's type. + if (Context.hasSameType(ParamType, ArgType)) { + // Okay: no conversion necessary + } else if (ParamType->isBooleanType()) { + // This is an integral-to-boolean conversion. + Arg = ImpCastExprToType(Arg, ParamType, CK_IntegralToBoolean).take(); + } else if (IsIntegralPromotion(Arg, ArgType, ParamType) || + !ParamType->isEnumeralType()) { + // This is an integral promotion or conversion. + Arg = ImpCastExprToType(Arg, ParamType, CK_IntegralCast).take(); + } else { + // We can't perform this conversion. + Diag(Arg->getLocStart(), + diag::err_template_arg_not_convertible) + << Arg->getType() << InstantiatedParamType << Arg->getSourceRange(); + Diag(Param->getLocation(), diag::note_template_param_here); + return ExprError(); + } + + // Add the value of this argument to the list of converted + // arguments. We use the bitwidth and signedness of the template + // parameter. + if (Arg->isValueDependent()) { + // The argument is value-dependent. Create a new + // TemplateArgument with the converted expression. + Converted = TemplateArgument(Arg); + return Owned(Arg); + } + + QualType IntegerType = Context.getCanonicalType(ParamType); + if (const EnumType *Enum = IntegerType->getAs<EnumType>()) + IntegerType = Context.getCanonicalType(Enum->getDecl()->getIntegerType()); + + if (ParamType->isBooleanType()) { + // Value must be zero or one. + Value = Value != 0; + unsigned AllowedBits = Context.getTypeSize(IntegerType); + if (Value.getBitWidth() != AllowedBits) + Value = Value.extOrTrunc(AllowedBits); + Value.setIsSigned(IntegerType->isSignedIntegerOrEnumerationType()); + } else { + llvm::APSInt OldValue = Value; + + // Coerce the template argument's value to the value it will have + // based on the template parameter's type. + unsigned AllowedBits = Context.getTypeSize(IntegerType); + if (Value.getBitWidth() != AllowedBits) + Value = Value.extOrTrunc(AllowedBits); + Value.setIsSigned(IntegerType->isSignedIntegerOrEnumerationType()); + + // Complain if an unsigned parameter received a negative value. + if (IntegerType->isUnsignedIntegerOrEnumerationType() + && (OldValue.isSigned() && OldValue.isNegative())) { + Diag(Arg->getLocStart(), diag::warn_template_arg_negative) + << OldValue.toString(10) << Value.toString(10) << Param->getType() + << Arg->getSourceRange(); + Diag(Param->getLocation(), diag::note_template_param_here); + } + + // Complain if we overflowed the template parameter's type. + unsigned RequiredBits; + if (IntegerType->isUnsignedIntegerOrEnumerationType()) + RequiredBits = OldValue.getActiveBits(); + else if (OldValue.isUnsigned()) + RequiredBits = OldValue.getActiveBits() + 1; + else + RequiredBits = OldValue.getMinSignedBits(); + if (RequiredBits > AllowedBits) { + Diag(Arg->getLocStart(), + diag::warn_template_arg_too_large) + << OldValue.toString(10) << Value.toString(10) << Param->getType() + << Arg->getSourceRange(); + Diag(Param->getLocation(), diag::note_template_param_here); + } + } + + Converted = TemplateArgument(Value, + ParamType->isEnumeralType() + ? Context.getCanonicalType(ParamType) + : IntegerType); + return Owned(Arg); + } + + QualType ArgType = Arg->getType(); + DeclAccessPair FoundResult; // temporary for ResolveOverloadedFunction + + // Handle pointer-to-function, reference-to-function, and + // pointer-to-member-function all in (roughly) the same way. + if (// -- For a non-type template-parameter of type pointer to + // function, only the function-to-pointer conversion (4.3) is + // applied. If the template-argument represents a set of + // overloaded functions (or a pointer to such), the matching + // function is selected from the set (13.4). + (ParamType->isPointerType() && + ParamType->getAs<PointerType>()->getPointeeType()->isFunctionType()) || + // -- For a non-type template-parameter of type reference to + // function, no conversions apply. If the template-argument + // represents a set of overloaded functions, the matching + // function is selected from the set (13.4). + (ParamType->isReferenceType() && + ParamType->getAs<ReferenceType>()->getPointeeType()->isFunctionType()) || + // -- For a non-type template-parameter of type pointer to + // member function, no conversions apply. If the + // template-argument represents a set of overloaded member + // functions, the matching member function is selected from + // the set (13.4). + (ParamType->isMemberPointerType() && + ParamType->getAs<MemberPointerType>()->getPointeeType() + ->isFunctionType())) { + + if (Arg->getType() == Context.OverloadTy) { + if (FunctionDecl *Fn = ResolveAddressOfOverloadedFunction(Arg, ParamType, + true, + FoundResult)) { + if (DiagnoseUseOfDecl(Fn, Arg->getLocStart())) + return ExprError(); + + Arg = FixOverloadedFunctionReference(Arg, FoundResult, Fn); + ArgType = Arg->getType(); + } else + return ExprError(); + } + + if (!ParamType->isMemberPointerType()) { + if (CheckTemplateArgumentAddressOfObjectOrFunction(*this, Param, + ParamType, + Arg, Converted)) + return ExprError(); + return Owned(Arg); + } + + if (CheckTemplateArgumentPointerToMember(*this, Param, ParamType, Arg, + Converted)) + return ExprError(); + return Owned(Arg); + } + + if (ParamType->isPointerType()) { + // -- for a non-type template-parameter of type pointer to + // object, qualification conversions (4.4) and the + // array-to-pointer conversion (4.2) are applied. + // C++0x also allows a value of std::nullptr_t. + assert(ParamType->getPointeeType()->isIncompleteOrObjectType() && + "Only object pointers allowed here"); + + if (CheckTemplateArgumentAddressOfObjectOrFunction(*this, Param, + ParamType, + Arg, Converted)) + return ExprError(); + return Owned(Arg); + } + + if (const ReferenceType *ParamRefType = ParamType->getAs<ReferenceType>()) { + // -- For a non-type template-parameter of type reference to + // object, no conversions apply. The type referred to by the + // reference may be more cv-qualified than the (otherwise + // identical) type of the template-argument. The + // template-parameter is bound directly to the + // template-argument, which must be an lvalue. + assert(ParamRefType->getPointeeType()->isIncompleteOrObjectType() && + "Only object references allowed here"); + + if (Arg->getType() == Context.OverloadTy) { + if (FunctionDecl *Fn = ResolveAddressOfOverloadedFunction(Arg, + ParamRefType->getPointeeType(), + true, + FoundResult)) { + if (DiagnoseUseOfDecl(Fn, Arg->getLocStart())) + return ExprError(); + + Arg = FixOverloadedFunctionReference(Arg, FoundResult, Fn); + ArgType = Arg->getType(); + } else + return ExprError(); + } + + if (CheckTemplateArgumentAddressOfObjectOrFunction(*this, Param, + ParamType, + Arg, Converted)) + return ExprError(); + return Owned(Arg); + } + + // Deal with parameters of type std::nullptr_t. + if (ParamType->isNullPtrType()) { + if (Arg->isTypeDependent() || Arg->isValueDependent()) { + Converted = TemplateArgument(Arg); + return Owned(Arg); + } + + switch (isNullPointerValueTemplateArgument(*this, Param, ParamType, Arg)) { + case NPV_NotNullPointer: + Diag(Arg->getExprLoc(), diag::err_template_arg_not_convertible) + << Arg->getType() << ParamType; + Diag(Param->getLocation(), diag::note_template_param_here); + return ExprError(); + + case NPV_Error: + return ExprError(); + + case NPV_NullPointer: + Converted = TemplateArgument((Decl *)0); + return Owned(Arg);; + } + } + + // -- For a non-type template-parameter of type pointer to data + // member, qualification conversions (4.4) are applied. + assert(ParamType->isMemberPointerType() && "Only pointers to members remain"); + + if (CheckTemplateArgumentPointerToMember(*this, Param, ParamType, Arg, + Converted)) + return ExprError(); + return Owned(Arg); +} + +/// \brief Check a template argument against its corresponding +/// template template parameter. +/// +/// This routine implements the semantics of C++ [temp.arg.template]. +/// It returns true if an error occurred, and false otherwise. +bool Sema::CheckTemplateArgument(TemplateTemplateParmDecl *Param, + const TemplateArgumentLoc &Arg) { + TemplateName Name = Arg.getArgument().getAsTemplate(); + TemplateDecl *Template = Name.getAsTemplateDecl(); + if (!Template) { + // Any dependent template name is fine. + assert(Name.isDependent() && "Non-dependent template isn't a declaration?"); + return false; + } + + // C++0x [temp.arg.template]p1: + // A template-argument for a template template-parameter shall be + // the name of a class template or an alias template, expressed as an + // id-expression. When the template-argument names a class template, only + // primary class templates are considered when matching the + // template template argument with the corresponding parameter; + // partial specializations are not considered even if their + // parameter lists match that of the template template parameter. + // + // Note that we also allow template template parameters here, which + // will happen when we are dealing with, e.g., class template + // partial specializations. + if (!isa<ClassTemplateDecl>(Template) && + !isa<TemplateTemplateParmDecl>(Template) && + !isa<TypeAliasTemplateDecl>(Template)) { + assert(isa<FunctionTemplateDecl>(Template) && + "Only function templates are possible here"); + Diag(Arg.getLocation(), diag::err_template_arg_not_class_template); + Diag(Template->getLocation(), diag::note_template_arg_refers_here_func) + << Template; + } + + return !TemplateParameterListsAreEqual(Template->getTemplateParameters(), + Param->getTemplateParameters(), + true, + TPL_TemplateTemplateArgumentMatch, + Arg.getLocation()); +} + +/// \brief Given a non-type template argument that refers to a +/// declaration and the type of its corresponding non-type template +/// parameter, produce an expression that properly refers to that +/// declaration. +ExprResult +Sema::BuildExpressionFromDeclTemplateArgument(const TemplateArgument &Arg, + QualType ParamType, + SourceLocation Loc) { + assert(Arg.getKind() == TemplateArgument::Declaration && + "Only declaration template arguments permitted here"); + + // For a NULL non-type template argument, return nullptr casted to the + // parameter's type. + if (!Arg.getAsDecl()) { + return ImpCastExprToType( + new (Context) CXXNullPtrLiteralExpr(Context.NullPtrTy, Loc), + ParamType, + ParamType->getAs<MemberPointerType>() + ? CK_NullToMemberPointer + : CK_NullToPointer); + } + + ValueDecl *VD = cast<ValueDecl>(Arg.getAsDecl()); + + if (VD->getDeclContext()->isRecord() && + (isa<CXXMethodDecl>(VD) || isa<FieldDecl>(VD))) { + // If the value is a class member, we might have a pointer-to-member. + // Determine whether the non-type template template parameter is of + // pointer-to-member type. If so, we need to build an appropriate + // expression for a pointer-to-member, since a "normal" DeclRefExpr + // would refer to the member itself. + if (ParamType->isMemberPointerType()) { + QualType ClassType + = Context.getTypeDeclType(cast<RecordDecl>(VD->getDeclContext())); + NestedNameSpecifier *Qualifier + = NestedNameSpecifier::Create(Context, 0, false, + ClassType.getTypePtr()); + CXXScopeSpec SS; + SS.MakeTrivial(Context, Qualifier, Loc); + + // The actual value-ness of this is unimportant, but for + // internal consistency's sake, references to instance methods + // are r-values. + ExprValueKind VK = VK_LValue; + if (isa<CXXMethodDecl>(VD) && cast<CXXMethodDecl>(VD)->isInstance()) + VK = VK_RValue; + + ExprResult RefExpr = BuildDeclRefExpr(VD, + VD->getType().getNonReferenceType(), + VK, + Loc, + &SS); + if (RefExpr.isInvalid()) + return ExprError(); + + RefExpr = CreateBuiltinUnaryOp(Loc, UO_AddrOf, RefExpr.get()); + + // We might need to perform a trailing qualification conversion, since + // the element type on the parameter could be more qualified than the + // element type in the expression we constructed. + bool ObjCLifetimeConversion; + if (IsQualificationConversion(((Expr*) RefExpr.get())->getType(), + ParamType.getUnqualifiedType(), false, + ObjCLifetimeConversion)) + RefExpr = ImpCastExprToType(RefExpr.take(), ParamType.getUnqualifiedType(), CK_NoOp); + + assert(!RefExpr.isInvalid() && + Context.hasSameType(((Expr*) RefExpr.get())->getType(), + ParamType.getUnqualifiedType())); + return move(RefExpr); + } + } + + QualType T = VD->getType().getNonReferenceType(); + if (ParamType->isPointerType()) { + // When the non-type template parameter is a pointer, take the + // address of the declaration. + ExprResult RefExpr = BuildDeclRefExpr(VD, T, VK_LValue, Loc); + if (RefExpr.isInvalid()) + return ExprError(); + + if (T->isFunctionType() || T->isArrayType()) { + // Decay functions and arrays. + RefExpr = DefaultFunctionArrayConversion(RefExpr.take()); + if (RefExpr.isInvalid()) + return ExprError(); + + return move(RefExpr); + } + + // Take the address of everything else + return CreateBuiltinUnaryOp(Loc, UO_AddrOf, RefExpr.get()); + } + + ExprValueKind VK = VK_RValue; + + // If the non-type template parameter has reference type, qualify the + // resulting declaration reference with the extra qualifiers on the + // type that the reference refers to. + if (const ReferenceType *TargetRef = ParamType->getAs<ReferenceType>()) { + VK = VK_LValue; + T = Context.getQualifiedType(T, + TargetRef->getPointeeType().getQualifiers()); + } + + return BuildDeclRefExpr(VD, T, VK, Loc); +} + +/// \brief Construct a new expression that refers to the given +/// integral template argument with the given source-location +/// information. +/// +/// This routine takes care of the mapping from an integral template +/// argument (which may have any integral type) to the appropriate +/// literal value. +ExprResult +Sema::BuildExpressionFromIntegralTemplateArgument(const TemplateArgument &Arg, + SourceLocation Loc) { + assert(Arg.getKind() == TemplateArgument::Integral && + "Operation is only valid for integral template arguments"); + QualType T = Arg.getIntegralType(); + if (T->isAnyCharacterType()) { + CharacterLiteral::CharacterKind Kind; + if (T->isWideCharType()) + Kind = CharacterLiteral::Wide; + else if (T->isChar16Type()) + Kind = CharacterLiteral::UTF16; + else if (T->isChar32Type()) + Kind = CharacterLiteral::UTF32; + else + Kind = CharacterLiteral::Ascii; + + return Owned(new (Context) CharacterLiteral( + Arg.getAsIntegral()->getZExtValue(), + Kind, T, Loc)); + } + + if (T->isBooleanType()) + return Owned(new (Context) CXXBoolLiteralExpr( + Arg.getAsIntegral()->getBoolValue(), + T, Loc)); + + if (T->isNullPtrType()) + return Owned(new (Context) CXXNullPtrLiteralExpr(Context.NullPtrTy, Loc)); + + // If this is an enum type that we're instantiating, we need to use an integer + // type the same size as the enumerator. We don't want to build an + // IntegerLiteral with enum type. + QualType BT; + if (const EnumType *ET = T->getAs<EnumType>()) + BT = ET->getDecl()->getIntegerType(); + else + BT = T; + + Expr *E = IntegerLiteral::Create(Context, *Arg.getAsIntegral(), BT, Loc); + if (T->isEnumeralType()) { + // FIXME: This is a hack. We need a better way to handle substituted + // non-type template parameters. + E = CStyleCastExpr::Create(Context, T, VK_RValue, CK_IntegralCast, E, 0, + Context.getTrivialTypeSourceInfo(T, Loc), + Loc, Loc); + } + + return Owned(E); +} + +/// \brief Match two template parameters within template parameter lists. +static bool MatchTemplateParameterKind(Sema &S, NamedDecl *New, NamedDecl *Old, + bool Complain, + Sema::TemplateParameterListEqualKind Kind, + SourceLocation TemplateArgLoc) { + // Check the actual kind (type, non-type, template). + if (Old->getKind() != New->getKind()) { + if (Complain) { + unsigned NextDiag = diag::err_template_param_different_kind; + if (TemplateArgLoc.isValid()) { + S.Diag(TemplateArgLoc, diag::err_template_arg_template_params_mismatch); + NextDiag = diag::note_template_param_different_kind; + } + S.Diag(New->getLocation(), NextDiag) + << (Kind != Sema::TPL_TemplateMatch); + S.Diag(Old->getLocation(), diag::note_template_prev_declaration) + << (Kind != Sema::TPL_TemplateMatch); + } + + return false; + } + + // Check that both are parameter packs are neither are parameter packs. + // However, if we are matching a template template argument to a + // template template parameter, the template template parameter can have + // a parameter pack where the template template argument does not. + if (Old->isTemplateParameterPack() != New->isTemplateParameterPack() && + !(Kind == Sema::TPL_TemplateTemplateArgumentMatch && + Old->isTemplateParameterPack())) { + if (Complain) { + unsigned NextDiag = diag::err_template_parameter_pack_non_pack; + if (TemplateArgLoc.isValid()) { + S.Diag(TemplateArgLoc, + diag::err_template_arg_template_params_mismatch); + NextDiag = diag::note_template_parameter_pack_non_pack; + } + + unsigned ParamKind = isa<TemplateTypeParmDecl>(New)? 0 + : isa<NonTypeTemplateParmDecl>(New)? 1 + : 2; + S.Diag(New->getLocation(), NextDiag) + << ParamKind << New->isParameterPack(); + S.Diag(Old->getLocation(), diag::note_template_parameter_pack_here) + << ParamKind << Old->isParameterPack(); + } + + return false; + } + + // For non-type template parameters, check the type of the parameter. + if (NonTypeTemplateParmDecl *OldNTTP + = dyn_cast<NonTypeTemplateParmDecl>(Old)) { + NonTypeTemplateParmDecl *NewNTTP = cast<NonTypeTemplateParmDecl>(New); + + // If we are matching a template template argument to a template + // template parameter and one of the non-type template parameter types + // is dependent, then we must wait until template instantiation time + // to actually compare the arguments. + if (Kind == Sema::TPL_TemplateTemplateArgumentMatch && + (OldNTTP->getType()->isDependentType() || + NewNTTP->getType()->isDependentType())) + return true; + + if (!S.Context.hasSameType(OldNTTP->getType(), NewNTTP->getType())) { + if (Complain) { + unsigned NextDiag = diag::err_template_nontype_parm_different_type; + if (TemplateArgLoc.isValid()) { + S.Diag(TemplateArgLoc, + diag::err_template_arg_template_params_mismatch); + NextDiag = diag::note_template_nontype_parm_different_type; + } + S.Diag(NewNTTP->getLocation(), NextDiag) + << NewNTTP->getType() + << (Kind != Sema::TPL_TemplateMatch); + S.Diag(OldNTTP->getLocation(), + diag::note_template_nontype_parm_prev_declaration) + << OldNTTP->getType(); + } + + return false; + } + + return true; + } + + // For template template parameters, check the template parameter types. + // The template parameter lists of template template + // parameters must agree. + if (TemplateTemplateParmDecl *OldTTP + = dyn_cast<TemplateTemplateParmDecl>(Old)) { + TemplateTemplateParmDecl *NewTTP = cast<TemplateTemplateParmDecl>(New); + return S.TemplateParameterListsAreEqual(NewTTP->getTemplateParameters(), + OldTTP->getTemplateParameters(), + Complain, + (Kind == Sema::TPL_TemplateMatch + ? Sema::TPL_TemplateTemplateParmMatch + : Kind), + TemplateArgLoc); + } + + return true; +} + +/// \brief Diagnose a known arity mismatch when comparing template argument +/// lists. +static +void DiagnoseTemplateParameterListArityMismatch(Sema &S, + TemplateParameterList *New, + TemplateParameterList *Old, + Sema::TemplateParameterListEqualKind Kind, + SourceLocation TemplateArgLoc) { + unsigned NextDiag = diag::err_template_param_list_different_arity; + if (TemplateArgLoc.isValid()) { + S.Diag(TemplateArgLoc, diag::err_template_arg_template_params_mismatch); + NextDiag = diag::note_template_param_list_different_arity; + } + S.Diag(New->getTemplateLoc(), NextDiag) + << (New->size() > Old->size()) + << (Kind != Sema::TPL_TemplateMatch) + << SourceRange(New->getTemplateLoc(), New->getRAngleLoc()); + S.Diag(Old->getTemplateLoc(), diag::note_template_prev_declaration) + << (Kind != Sema::TPL_TemplateMatch) + << SourceRange(Old->getTemplateLoc(), Old->getRAngleLoc()); +} + +/// \brief Determine whether the given template parameter lists are +/// equivalent. +/// +/// \param New The new template parameter list, typically written in the +/// source code as part of a new template declaration. +/// +/// \param Old The old template parameter list, typically found via +/// name lookup of the template declared with this template parameter +/// list. +/// +/// \param Complain If true, this routine will produce a diagnostic if +/// the template parameter lists are not equivalent. +/// +/// \param Kind describes how we are to match the template parameter lists. +/// +/// \param TemplateArgLoc If this source location is valid, then we +/// are actually checking the template parameter list of a template +/// argument (New) against the template parameter list of its +/// corresponding template template parameter (Old). We produce +/// slightly different diagnostics in this scenario. +/// +/// \returns True if the template parameter lists are equal, false +/// otherwise. +bool +Sema::TemplateParameterListsAreEqual(TemplateParameterList *New, + TemplateParameterList *Old, + bool Complain, + TemplateParameterListEqualKind Kind, + SourceLocation TemplateArgLoc) { + if (Old->size() != New->size() && Kind != TPL_TemplateTemplateArgumentMatch) { + if (Complain) + DiagnoseTemplateParameterListArityMismatch(*this, New, Old, Kind, + TemplateArgLoc); + + return false; + } + + // C++0x [temp.arg.template]p3: + // A template-argument matches a template template-parameter (call it P) + // when each of the template parameters in the template-parameter-list of + // the template-argument's corresponding class template or alias template + // (call it A) matches the corresponding template parameter in the + // template-parameter-list of P. [...] + TemplateParameterList::iterator NewParm = New->begin(); + TemplateParameterList::iterator NewParmEnd = New->end(); + for (TemplateParameterList::iterator OldParm = Old->begin(), + OldParmEnd = Old->end(); + OldParm != OldParmEnd; ++OldParm) { + if (Kind != TPL_TemplateTemplateArgumentMatch || + !(*OldParm)->isTemplateParameterPack()) { + if (NewParm == NewParmEnd) { + if (Complain) + DiagnoseTemplateParameterListArityMismatch(*this, New, Old, Kind, + TemplateArgLoc); + + return false; + } + + if (!MatchTemplateParameterKind(*this, *NewParm, *OldParm, Complain, + Kind, TemplateArgLoc)) + return false; + + ++NewParm; + continue; + } + + // C++0x [temp.arg.template]p3: + // [...] When P's template- parameter-list contains a template parameter + // pack (14.5.3), the template parameter pack will match zero or more + // template parameters or template parameter packs in the + // template-parameter-list of A with the same type and form as the + // template parameter pack in P (ignoring whether those template + // parameters are template parameter packs). + for (; NewParm != NewParmEnd; ++NewParm) { + if (!MatchTemplateParameterKind(*this, *NewParm, *OldParm, Complain, + Kind, TemplateArgLoc)) + return false; + } + } + + // Make sure we exhausted all of the arguments. + if (NewParm != NewParmEnd) { + if (Complain) + DiagnoseTemplateParameterListArityMismatch(*this, New, Old, Kind, + TemplateArgLoc); + + return false; + } + + return true; +} + +/// \brief Check whether a template can be declared within this scope. +/// +/// If the template declaration is valid in this scope, returns +/// false. Otherwise, issues a diagnostic and returns true. +bool +Sema::CheckTemplateDeclScope(Scope *S, TemplateParameterList *TemplateParams) { + if (!S) + return false; + + // Find the nearest enclosing declaration scope. + while ((S->getFlags() & Scope::DeclScope) == 0 || + (S->getFlags() & Scope::TemplateParamScope) != 0) + S = S->getParent(); + + // C++ [temp]p2: + // A template-declaration can appear only as a namespace scope or + // class scope declaration. + DeclContext *Ctx = static_cast<DeclContext *>(S->getEntity()); + if (Ctx && isa<LinkageSpecDecl>(Ctx) && + cast<LinkageSpecDecl>(Ctx)->getLanguage() != LinkageSpecDecl::lang_cxx) + return Diag(TemplateParams->getTemplateLoc(), diag::err_template_linkage) + << TemplateParams->getSourceRange(); + + while (Ctx && isa<LinkageSpecDecl>(Ctx)) + Ctx = Ctx->getParent(); + + if (Ctx && (Ctx->isFileContext() || Ctx->isRecord())) + return false; + + return Diag(TemplateParams->getTemplateLoc(), + diag::err_template_outside_namespace_or_class_scope) + << TemplateParams->getSourceRange(); +} + +/// \brief Determine what kind of template specialization the given declaration +/// is. +static TemplateSpecializationKind getTemplateSpecializationKind(Decl *D) { + if (!D) + return TSK_Undeclared; + + if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(D)) + return Record->getTemplateSpecializationKind(); + if (FunctionDecl *Function = dyn_cast<FunctionDecl>(D)) + return Function->getTemplateSpecializationKind(); + if (VarDecl *Var = dyn_cast<VarDecl>(D)) + return Var->getTemplateSpecializationKind(); + + return TSK_Undeclared; +} + +/// \brief Check whether a specialization is well-formed in the current +/// context. +/// +/// This routine determines whether a template specialization can be declared +/// in the current context (C++ [temp.expl.spec]p2). +/// +/// \param S the semantic analysis object for which this check is being +/// performed. +/// +/// \param Specialized the entity being specialized or instantiated, which +/// may be a kind of template (class template, function template, etc.) or +/// a member of a class template (member function, static data member, +/// member class). +/// +/// \param PrevDecl the previous declaration of this entity, if any. +/// +/// \param Loc the location of the explicit specialization or instantiation of +/// this entity. +/// +/// \param IsPartialSpecialization whether this is a partial specialization of +/// a class template. +/// +/// \returns true if there was an error that we cannot recover from, false +/// otherwise. +static bool CheckTemplateSpecializationScope(Sema &S, + NamedDecl *Specialized, + NamedDecl *PrevDecl, + SourceLocation Loc, + bool IsPartialSpecialization) { + // Keep these "kind" numbers in sync with the %select statements in the + // various diagnostics emitted by this routine. + int EntityKind = 0; + if (isa<ClassTemplateDecl>(Specialized)) + EntityKind = IsPartialSpecialization? 1 : 0; + else if (isa<FunctionTemplateDecl>(Specialized)) + EntityKind = 2; + else if (isa<CXXMethodDecl>(Specialized)) + EntityKind = 3; + else if (isa<VarDecl>(Specialized)) + EntityKind = 4; + else if (isa<RecordDecl>(Specialized)) + EntityKind = 5; + else if (isa<EnumDecl>(Specialized) && S.getLangOpts().CPlusPlus0x) + EntityKind = 6; + else { + S.Diag(Loc, diag::err_template_spec_unknown_kind) + << S.getLangOpts().CPlusPlus0x; + S.Diag(Specialized->getLocation(), diag::note_specialized_entity); + return true; + } + + // C++ [temp.expl.spec]p2: + // An explicit specialization shall be declared in the namespace + // of which the template is a member, or, for member templates, in + // the namespace of which the enclosing class or enclosing class + // template is a member. An explicit specialization of a member + // function, member class or static data member of a class + // template shall be declared in the namespace of which the class + // template is a member. Such a declaration may also be a + // definition. If the declaration is not a definition, the + // specialization may be defined later in the name- space in which + // the explicit specialization was declared, or in a namespace + // that encloses the one in which the explicit specialization was + // declared. + if (S.CurContext->getRedeclContext()->isFunctionOrMethod()) { + S.Diag(Loc, diag::err_template_spec_decl_function_scope) + << Specialized; + return true; + } + + if (S.CurContext->isRecord() && !IsPartialSpecialization) { + if (S.getLangOpts().MicrosoftExt) { + // Do not warn for class scope explicit specialization during + // instantiation, warning was already emitted during pattern + // semantic analysis. + if (!S.ActiveTemplateInstantiations.size()) + S.Diag(Loc, diag::ext_function_specialization_in_class) + << Specialized; + } else { + S.Diag(Loc, diag::err_template_spec_decl_class_scope) + << Specialized; + return true; + } + } + + if (S.CurContext->isRecord() && + !S.CurContext->Equals(Specialized->getDeclContext())) { + // Make sure that we're specializing in the right record context. + // Otherwise, things can go horribly wrong. + S.Diag(Loc, diag::err_template_spec_decl_class_scope) + << Specialized; + return true; + } + + // C++ [temp.class.spec]p6: + // A class template partial specialization may be declared or redeclared + // in any namespace scope in which its definition may be defined (14.5.1 + // and 14.5.2). + bool ComplainedAboutScope = false; + DeclContext *SpecializedContext + = Specialized->getDeclContext()->getEnclosingNamespaceContext(); + DeclContext *DC = S.CurContext->getEnclosingNamespaceContext(); + if ((!PrevDecl || + getTemplateSpecializationKind(PrevDecl) == TSK_Undeclared || + getTemplateSpecializationKind(PrevDecl) == TSK_ImplicitInstantiation)){ + // C++ [temp.exp.spec]p2: + // An explicit specialization shall be declared in the namespace of which + // the template is a member, or, for member templates, in the namespace + // of which the enclosing class or enclosing class template is a member. + // An explicit specialization of a member function, member class or + // static data member of a class template shall be declared in the + // namespace of which the class template is a member. + // + // C++0x [temp.expl.spec]p2: + // An explicit specialization shall be declared in a namespace enclosing + // the specialized template. + if (!DC->InEnclosingNamespaceSetOf(SpecializedContext)) { + bool IsCPlusPlus0xExtension = DC->Encloses(SpecializedContext); + if (isa<TranslationUnitDecl>(SpecializedContext)) { + assert(!IsCPlusPlus0xExtension && + "DC encloses TU but isn't in enclosing namespace set"); + S.Diag(Loc, diag::err_template_spec_decl_out_of_scope_global) + << EntityKind << Specialized; + } else if (isa<NamespaceDecl>(SpecializedContext)) { + int Diag; + if (!IsCPlusPlus0xExtension) + Diag = diag::err_template_spec_decl_out_of_scope; + else if (!S.getLangOpts().CPlusPlus0x) + Diag = diag::ext_template_spec_decl_out_of_scope; + else + Diag = diag::warn_cxx98_compat_template_spec_decl_out_of_scope; + S.Diag(Loc, Diag) + << EntityKind << Specialized << cast<NamedDecl>(SpecializedContext); + } + + S.Diag(Specialized->getLocation(), diag::note_specialized_entity); + ComplainedAboutScope = + !(IsCPlusPlus0xExtension && S.getLangOpts().CPlusPlus0x); + } + } + + // Make sure that this redeclaration (or definition) occurs in an enclosing + // namespace. + // Note that HandleDeclarator() performs this check for explicit + // specializations of function templates, static data members, and member + // functions, so we skip the check here for those kinds of entities. + // FIXME: HandleDeclarator's diagnostics aren't quite as good, though. + // Should we refactor that check, so that it occurs later? + if (!ComplainedAboutScope && !DC->Encloses(SpecializedContext) && + !(isa<FunctionTemplateDecl>(Specialized) || isa<VarDecl>(Specialized) || + isa<FunctionDecl>(Specialized))) { + if (isa<TranslationUnitDecl>(SpecializedContext)) + S.Diag(Loc, diag::err_template_spec_redecl_global_scope) + << EntityKind << Specialized; + else if (isa<NamespaceDecl>(SpecializedContext)) + S.Diag(Loc, diag::err_template_spec_redecl_out_of_scope) + << EntityKind << Specialized + << cast<NamedDecl>(SpecializedContext); + + S.Diag(Specialized->getLocation(), diag::note_specialized_entity); + } + + // FIXME: check for specialization-after-instantiation errors and such. + + return false; +} + +/// \brief Subroutine of Sema::CheckClassTemplatePartialSpecializationArgs +/// that checks non-type template partial specialization arguments. +static bool CheckNonTypeClassTemplatePartialSpecializationArgs(Sema &S, + NonTypeTemplateParmDecl *Param, + const TemplateArgument *Args, + unsigned NumArgs) { + for (unsigned I = 0; I != NumArgs; ++I) { + if (Args[I].getKind() == TemplateArgument::Pack) { + if (CheckNonTypeClassTemplatePartialSpecializationArgs(S, Param, + Args[I].pack_begin(), + Args[I].pack_size())) + return true; + + continue; + } + + Expr *ArgExpr = Args[I].getAsExpr(); + if (!ArgExpr) { + continue; + } + + // We can have a pack expansion of any of the bullets below. + if (PackExpansionExpr *Expansion = dyn_cast<PackExpansionExpr>(ArgExpr)) + ArgExpr = Expansion->getPattern(); + + // Strip off any implicit casts we added as part of type checking. + while (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(ArgExpr)) + ArgExpr = ICE->getSubExpr(); + + // C++ [temp.class.spec]p8: + // A non-type argument is non-specialized if it is the name of a + // non-type parameter. All other non-type arguments are + // specialized. + // + // Below, we check the two conditions that only apply to + // specialized non-type arguments, so skip any non-specialized + // arguments. + if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(ArgExpr)) + if (isa<NonTypeTemplateParmDecl>(DRE->getDecl())) + continue; + + // C++ [temp.class.spec]p9: + // Within the argument list of a class template partial + // specialization, the following restrictions apply: + // -- A partially specialized non-type argument expression + // shall not involve a template parameter of the partial + // specialization except when the argument expression is a + // simple identifier. + if (ArgExpr->isTypeDependent() || ArgExpr->isValueDependent()) { + S.Diag(ArgExpr->getLocStart(), + diag::err_dependent_non_type_arg_in_partial_spec) + << ArgExpr->getSourceRange(); + return true; + } + + // -- The type of a template parameter corresponding to a + // specialized non-type argument shall not be dependent on a + // parameter of the specialization. + if (Param->getType()->isDependentType()) { + S.Diag(ArgExpr->getLocStart(), + diag::err_dependent_typed_non_type_arg_in_partial_spec) + << Param->getType() + << ArgExpr->getSourceRange(); + S.Diag(Param->getLocation(), diag::note_template_param_here); + return true; + } + } + + return false; +} + +/// \brief Check the non-type template arguments of a class template +/// partial specialization according to C++ [temp.class.spec]p9. +/// +/// \param TemplateParams the template parameters of the primary class +/// template. +/// +/// \param TemplateArg the template arguments of the class template +/// partial specialization. +/// +/// \returns true if there was an error, false otherwise. +static bool CheckClassTemplatePartialSpecializationArgs(Sema &S, + TemplateParameterList *TemplateParams, + SmallVectorImpl<TemplateArgument> &TemplateArgs) { + const TemplateArgument *ArgList = TemplateArgs.data(); + + for (unsigned I = 0, N = TemplateParams->size(); I != N; ++I) { + NonTypeTemplateParmDecl *Param + = dyn_cast<NonTypeTemplateParmDecl>(TemplateParams->getParam(I)); + if (!Param) + continue; + + if (CheckNonTypeClassTemplatePartialSpecializationArgs(S, Param, + &ArgList[I], 1)) + return true; + } + + return false; +} + +DeclResult +Sema::ActOnClassTemplateSpecialization(Scope *S, unsigned TagSpec, + TagUseKind TUK, + SourceLocation KWLoc, + SourceLocation ModulePrivateLoc, + CXXScopeSpec &SS, + TemplateTy TemplateD, + SourceLocation TemplateNameLoc, + SourceLocation LAngleLoc, + ASTTemplateArgsPtr TemplateArgsIn, + SourceLocation RAngleLoc, + AttributeList *Attr, + MultiTemplateParamsArg TemplateParameterLists) { + assert(TUK != TUK_Reference && "References are not specializations"); + + // NOTE: KWLoc is the location of the tag keyword. This will instead + // store the location of the outermost template keyword in the declaration. + SourceLocation TemplateKWLoc = TemplateParameterLists.size() > 0 + ? TemplateParameterLists.get()[0]->getTemplateLoc() : SourceLocation(); + + // Find the class template we're specializing + TemplateName Name = TemplateD.getAsVal<TemplateName>(); + ClassTemplateDecl *ClassTemplate + = dyn_cast_or_null<ClassTemplateDecl>(Name.getAsTemplateDecl()); + + if (!ClassTemplate) { + Diag(TemplateNameLoc, diag::err_not_class_template_specialization) + << (Name.getAsTemplateDecl() && + isa<TemplateTemplateParmDecl>(Name.getAsTemplateDecl())); + return true; + } + + bool isExplicitSpecialization = false; + bool isPartialSpecialization = false; + + // Check the validity of the template headers that introduce this + // template. + // FIXME: We probably shouldn't complain about these headers for + // friend declarations. + bool Invalid = false; + TemplateParameterList *TemplateParams + = MatchTemplateParametersToScopeSpecifier(TemplateNameLoc, + TemplateNameLoc, + SS, + (TemplateParameterList**)TemplateParameterLists.get(), + TemplateParameterLists.size(), + TUK == TUK_Friend, + isExplicitSpecialization, + Invalid); + if (Invalid) + return true; + + if (TemplateParams && TemplateParams->size() > 0) { + isPartialSpecialization = true; + + if (TUK == TUK_Friend) { + Diag(KWLoc, diag::err_partial_specialization_friend) + << SourceRange(LAngleLoc, RAngleLoc); + return true; + } + + // C++ [temp.class.spec]p10: + // The template parameter list of a specialization shall not + // contain default template argument values. + for (unsigned I = 0, N = TemplateParams->size(); I != N; ++I) { + Decl *Param = TemplateParams->getParam(I); + if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(Param)) { + if (TTP->hasDefaultArgument()) { + Diag(TTP->getDefaultArgumentLoc(), + diag::err_default_arg_in_partial_spec); + TTP->removeDefaultArgument(); + } + } else if (NonTypeTemplateParmDecl *NTTP + = dyn_cast<NonTypeTemplateParmDecl>(Param)) { + if (Expr *DefArg = NTTP->getDefaultArgument()) { + Diag(NTTP->getDefaultArgumentLoc(), + diag::err_default_arg_in_partial_spec) + << DefArg->getSourceRange(); + NTTP->removeDefaultArgument(); + } + } else { + TemplateTemplateParmDecl *TTP = cast<TemplateTemplateParmDecl>(Param); + if (TTP->hasDefaultArgument()) { + Diag(TTP->getDefaultArgument().getLocation(), + diag::err_default_arg_in_partial_spec) + << TTP->getDefaultArgument().getSourceRange(); + TTP->removeDefaultArgument(); + } + } + } + } else if (TemplateParams) { + if (TUK == TUK_Friend) + Diag(KWLoc, diag::err_template_spec_friend) + << FixItHint::CreateRemoval( + SourceRange(TemplateParams->getTemplateLoc(), + TemplateParams->getRAngleLoc())) + << SourceRange(LAngleLoc, RAngleLoc); + else + isExplicitSpecialization = true; + } else if (TUK != TUK_Friend) { + Diag(KWLoc, diag::err_template_spec_needs_header) + << FixItHint::CreateInsertion(KWLoc, "template<> "); + isExplicitSpecialization = true; + } + + // Check that the specialization uses the same tag kind as the + // original template. + TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec); + assert(Kind != TTK_Enum && "Invalid enum tag in class template spec!"); + if (!isAcceptableTagRedeclaration(ClassTemplate->getTemplatedDecl(), + Kind, TUK == TUK_Definition, KWLoc, + *ClassTemplate->getIdentifier())) { + Diag(KWLoc, diag::err_use_with_wrong_tag) + << ClassTemplate + << FixItHint::CreateReplacement(KWLoc, + ClassTemplate->getTemplatedDecl()->getKindName()); + Diag(ClassTemplate->getTemplatedDecl()->getLocation(), + diag::note_previous_use); + Kind = ClassTemplate->getTemplatedDecl()->getTagKind(); + } + + // Translate the parser's template argument list in our AST format. + TemplateArgumentListInfo TemplateArgs; + TemplateArgs.setLAngleLoc(LAngleLoc); + TemplateArgs.setRAngleLoc(RAngleLoc); + translateTemplateArguments(TemplateArgsIn, TemplateArgs); + + // Check for unexpanded parameter packs in any of the template arguments. + for (unsigned I = 0, N = TemplateArgs.size(); I != N; ++I) + if (DiagnoseUnexpandedParameterPack(TemplateArgs[I], + UPPC_PartialSpecialization)) + return true; + + // Check that the template argument list is well-formed for this + // template. + SmallVector<TemplateArgument, 4> Converted; + if (CheckTemplateArgumentList(ClassTemplate, TemplateNameLoc, + TemplateArgs, false, Converted)) + return true; + + // Find the class template (partial) specialization declaration that + // corresponds to these arguments. + if (isPartialSpecialization) { + if (CheckClassTemplatePartialSpecializationArgs(*this, + ClassTemplate->getTemplateParameters(), + Converted)) + return true; + + bool InstantiationDependent; + if (!Name.isDependent() && + !TemplateSpecializationType::anyDependentTemplateArguments( + TemplateArgs.getArgumentArray(), + TemplateArgs.size(), + InstantiationDependent)) { + Diag(TemplateNameLoc, diag::err_partial_spec_fully_specialized) + << ClassTemplate->getDeclName(); + isPartialSpecialization = false; + } + } + + void *InsertPos = 0; + ClassTemplateSpecializationDecl *PrevDecl = 0; + + if (isPartialSpecialization) + // FIXME: Template parameter list matters, too + PrevDecl + = ClassTemplate->findPartialSpecialization(Converted.data(), + Converted.size(), + InsertPos); + else + PrevDecl + = ClassTemplate->findSpecialization(Converted.data(), + Converted.size(), InsertPos); + + ClassTemplateSpecializationDecl *Specialization = 0; + + // Check whether we can declare a class template specialization in + // the current scope. + if (TUK != TUK_Friend && + CheckTemplateSpecializationScope(*this, ClassTemplate, PrevDecl, + TemplateNameLoc, + isPartialSpecialization)) + return true; + + // The canonical type + QualType CanonType; + if (PrevDecl && + (PrevDecl->getSpecializationKind() == TSK_Undeclared || + TUK == TUK_Friend)) { + // Since the only prior class template specialization with these + // arguments was referenced but not declared, or we're only + // referencing this specialization as a friend, reuse that + // declaration node as our own, updating its source location and + // the list of outer template parameters to reflect our new declaration. + Specialization = PrevDecl; + Specialization->setLocation(TemplateNameLoc); + if (TemplateParameterLists.size() > 0) { + Specialization->setTemplateParameterListsInfo(Context, + TemplateParameterLists.size(), + (TemplateParameterList**) TemplateParameterLists.release()); + } + PrevDecl = 0; + CanonType = Context.getTypeDeclType(Specialization); + } else if (isPartialSpecialization) { + // Build the canonical type that describes the converted template + // arguments of the class template partial specialization. + TemplateName CanonTemplate = Context.getCanonicalTemplateName(Name); + CanonType = Context.getTemplateSpecializationType(CanonTemplate, + Converted.data(), + Converted.size()); + + if (Context.hasSameType(CanonType, + ClassTemplate->getInjectedClassNameSpecialization())) { + // C++ [temp.class.spec]p9b3: + // + // -- The argument list of the specialization shall not be identical + // to the implicit argument list of the primary template. + Diag(TemplateNameLoc, diag::err_partial_spec_args_match_primary_template) + << (TUK == TUK_Definition) + << FixItHint::CreateRemoval(SourceRange(LAngleLoc, RAngleLoc)); + return CheckClassTemplate(S, TagSpec, TUK, KWLoc, SS, + ClassTemplate->getIdentifier(), + TemplateNameLoc, + Attr, + TemplateParams, + AS_none, /*ModulePrivateLoc=*/SourceLocation(), + TemplateParameterLists.size() - 1, + (TemplateParameterList**) TemplateParameterLists.release()); + } + + // Create a new class template partial specialization declaration node. + ClassTemplatePartialSpecializationDecl *PrevPartial + = cast_or_null<ClassTemplatePartialSpecializationDecl>(PrevDecl); + unsigned SequenceNumber = PrevPartial? PrevPartial->getSequenceNumber() + : ClassTemplate->getNextPartialSpecSequenceNumber(); + ClassTemplatePartialSpecializationDecl *Partial + = ClassTemplatePartialSpecializationDecl::Create(Context, Kind, + ClassTemplate->getDeclContext(), + KWLoc, TemplateNameLoc, + TemplateParams, + ClassTemplate, + Converted.data(), + Converted.size(), + TemplateArgs, + CanonType, + PrevPartial, + SequenceNumber); + SetNestedNameSpecifier(Partial, SS); + if (TemplateParameterLists.size() > 1 && SS.isSet()) { + Partial->setTemplateParameterListsInfo(Context, + TemplateParameterLists.size() - 1, + (TemplateParameterList**) TemplateParameterLists.release()); + } + + if (!PrevPartial) + ClassTemplate->AddPartialSpecialization(Partial, InsertPos); + Specialization = Partial; + + // If we are providing an explicit specialization of a member class + // template specialization, make a note of that. + if (PrevPartial && PrevPartial->getInstantiatedFromMember()) + PrevPartial->setMemberSpecialization(); + + // Check that all of the template parameters of the class template + // partial specialization are deducible from the template + // arguments. If not, this class template partial specialization + // will never be used. + llvm::SmallBitVector DeducibleParams(TemplateParams->size()); + MarkUsedTemplateParameters(Partial->getTemplateArgs(), true, + TemplateParams->getDepth(), + DeducibleParams); + + if (!DeducibleParams.all()) { + unsigned NumNonDeducible = DeducibleParams.size()-DeducibleParams.count(); + Diag(TemplateNameLoc, diag::warn_partial_specs_not_deducible) + << (NumNonDeducible > 1) + << SourceRange(TemplateNameLoc, RAngleLoc); + for (unsigned I = 0, N = DeducibleParams.size(); I != N; ++I) { + if (!DeducibleParams[I]) { + NamedDecl *Param = cast<NamedDecl>(TemplateParams->getParam(I)); + if (Param->getDeclName()) + Diag(Param->getLocation(), + diag::note_partial_spec_unused_parameter) + << Param->getDeclName(); + else + Diag(Param->getLocation(), + diag::note_partial_spec_unused_parameter) + << "<anonymous>"; + } + } + } + } else { + // Create a new class template specialization declaration node for + // this explicit specialization or friend declaration. + Specialization + = ClassTemplateSpecializationDecl::Create(Context, Kind, + ClassTemplate->getDeclContext(), + KWLoc, TemplateNameLoc, + ClassTemplate, + Converted.data(), + Converted.size(), + PrevDecl); + SetNestedNameSpecifier(Specialization, SS); + if (TemplateParameterLists.size() > 0) { + Specialization->setTemplateParameterListsInfo(Context, + TemplateParameterLists.size(), + (TemplateParameterList**) TemplateParameterLists.release()); + } + + if (!PrevDecl) + ClassTemplate->AddSpecialization(Specialization, InsertPos); + + CanonType = Context.getTypeDeclType(Specialization); + } + + // C++ [temp.expl.spec]p6: + // If a template, a member template or the member of a class template is + // explicitly specialized then that specialization shall be declared + // before the first use of that specialization that would cause an implicit + // instantiation to take place, in every translation unit in which such a + // use occurs; no diagnostic is required. + if (PrevDecl && PrevDecl->getPointOfInstantiation().isValid()) { + bool Okay = false; + for (Decl *Prev = PrevDecl; Prev; Prev = Prev->getPreviousDecl()) { + // Is there any previous explicit specialization declaration? + if (getTemplateSpecializationKind(Prev) == TSK_ExplicitSpecialization) { + Okay = true; + break; + } + } + + if (!Okay) { + SourceRange Range(TemplateNameLoc, RAngleLoc); + Diag(TemplateNameLoc, diag::err_specialization_after_instantiation) + << Context.getTypeDeclType(Specialization) << Range; + + Diag(PrevDecl->getPointOfInstantiation(), + diag::note_instantiation_required_here) + << (PrevDecl->getTemplateSpecializationKind() + != TSK_ImplicitInstantiation); + return true; + } + } + + // If this is not a friend, note that this is an explicit specialization. + if (TUK != TUK_Friend) + Specialization->setSpecializationKind(TSK_ExplicitSpecialization); + + // Check that this isn't a redefinition of this specialization. + if (TUK == TUK_Definition) { + if (RecordDecl *Def = Specialization->getDefinition()) { + SourceRange Range(TemplateNameLoc, RAngleLoc); + Diag(TemplateNameLoc, diag::err_redefinition) + << Context.getTypeDeclType(Specialization) << Range; + Diag(Def->getLocation(), diag::note_previous_definition); + Specialization->setInvalidDecl(); + return true; + } + } + + if (Attr) + ProcessDeclAttributeList(S, Specialization, Attr); + + if (ModulePrivateLoc.isValid()) + Diag(Specialization->getLocation(), diag::err_module_private_specialization) + << (isPartialSpecialization? 1 : 0) + << FixItHint::CreateRemoval(ModulePrivateLoc); + + // Build the fully-sugared type for this class template + // specialization as the user wrote in the specialization + // itself. This means that we'll pretty-print the type retrieved + // from the specialization's declaration the way that the user + // actually wrote the specialization, rather than formatting the + // name based on the "canonical" representation used to store the + // template arguments in the specialization. + TypeSourceInfo *WrittenTy + = Context.getTemplateSpecializationTypeInfo(Name, TemplateNameLoc, + TemplateArgs, CanonType); + if (TUK != TUK_Friend) { + Specialization->setTypeAsWritten(WrittenTy); + Specialization->setTemplateKeywordLoc(TemplateKWLoc); + } + TemplateArgsIn.release(); + + // C++ [temp.expl.spec]p9: + // A template explicit specialization is in the scope of the + // namespace in which the template was defined. + // + // We actually implement this paragraph where we set the semantic + // context (in the creation of the ClassTemplateSpecializationDecl), + // but we also maintain the lexical context where the actual + // definition occurs. + Specialization->setLexicalDeclContext(CurContext); + + // We may be starting the definition of this specialization. + if (TUK == TUK_Definition) + Specialization->startDefinition(); + + if (TUK == TUK_Friend) { + FriendDecl *Friend = FriendDecl::Create(Context, CurContext, + TemplateNameLoc, + WrittenTy, + /*FIXME:*/KWLoc); + Friend->setAccess(AS_public); + CurContext->addDecl(Friend); + } else { + // Add the specialization into its lexical context, so that it can + // be seen when iterating through the list of declarations in that + // context. However, specializations are not found by name lookup. + CurContext->addDecl(Specialization); + } + return Specialization; +} + +Decl *Sema::ActOnTemplateDeclarator(Scope *S, + MultiTemplateParamsArg TemplateParameterLists, + Declarator &D) { + return HandleDeclarator(S, D, move(TemplateParameterLists)); +} + +Decl *Sema::ActOnStartOfFunctionTemplateDef(Scope *FnBodyScope, + MultiTemplateParamsArg TemplateParameterLists, + Declarator &D) { + assert(getCurFunctionDecl() == 0 && "Function parsing confused"); + DeclaratorChunk::FunctionTypeInfo &FTI = D.getFunctionTypeInfo(); + + if (FTI.hasPrototype) { + // FIXME: Diagnose arguments without names in C. + } + + Scope *ParentScope = FnBodyScope->getParent(); + + D.setFunctionDefinitionKind(FDK_Definition); + Decl *DP = HandleDeclarator(ParentScope, D, + move(TemplateParameterLists)); + if (FunctionTemplateDecl *FunctionTemplate + = dyn_cast_or_null<FunctionTemplateDecl>(DP)) + return ActOnStartOfFunctionDef(FnBodyScope, + FunctionTemplate->getTemplatedDecl()); + if (FunctionDecl *Function = dyn_cast_or_null<FunctionDecl>(DP)) + return ActOnStartOfFunctionDef(FnBodyScope, Function); + return 0; +} + +/// \brief Strips various properties off an implicit instantiation +/// that has just been explicitly specialized. +static void StripImplicitInstantiation(NamedDecl *D) { + // FIXME: "make check" is clean if the call to dropAttrs() is commented out. + D->dropAttrs(); + + if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { + FD->setInlineSpecified(false); + } +} + +/// \brief Compute the diagnostic location for an explicit instantiation +// declaration or definition. +static SourceLocation DiagLocForExplicitInstantiation( + NamedDecl* D, SourceLocation PointOfInstantiation) { + // Explicit instantiations following a specialization have no effect and + // hence no PointOfInstantiation. In that case, walk decl backwards + // until a valid name loc is found. + SourceLocation PrevDiagLoc = PointOfInstantiation; + for (Decl *Prev = D; Prev && !PrevDiagLoc.isValid(); + Prev = Prev->getPreviousDecl()) { + PrevDiagLoc = Prev->getLocation(); + } + assert(PrevDiagLoc.isValid() && + "Explicit instantiation without point of instantiation?"); + return PrevDiagLoc; +} + +/// \brief Diagnose cases where we have an explicit template specialization +/// before/after an explicit template instantiation, producing diagnostics +/// for those cases where they are required and determining whether the +/// new specialization/instantiation will have any effect. +/// +/// \param NewLoc the location of the new explicit specialization or +/// instantiation. +/// +/// \param NewTSK the kind of the new explicit specialization or instantiation. +/// +/// \param PrevDecl the previous declaration of the entity. +/// +/// \param PrevTSK the kind of the old explicit specialization or instantiatin. +/// +/// \param PrevPointOfInstantiation if valid, indicates where the previus +/// declaration was instantiated (either implicitly or explicitly). +/// +/// \param HasNoEffect will be set to true to indicate that the new +/// specialization or instantiation has no effect and should be ignored. +/// +/// \returns true if there was an error that should prevent the introduction of +/// the new declaration into the AST, false otherwise. +bool +Sema::CheckSpecializationInstantiationRedecl(SourceLocation NewLoc, + TemplateSpecializationKind NewTSK, + NamedDecl *PrevDecl, + TemplateSpecializationKind PrevTSK, + SourceLocation PrevPointOfInstantiation, + bool &HasNoEffect) { + HasNoEffect = false; + + switch (NewTSK) { + case TSK_Undeclared: + case TSK_ImplicitInstantiation: + llvm_unreachable("Don't check implicit instantiations here"); + + case TSK_ExplicitSpecialization: + switch (PrevTSK) { + case TSK_Undeclared: + case TSK_ExplicitSpecialization: + // Okay, we're just specializing something that is either already + // explicitly specialized or has merely been mentioned without any + // instantiation. + return false; + + case TSK_ImplicitInstantiation: + if (PrevPointOfInstantiation.isInvalid()) { + // The declaration itself has not actually been instantiated, so it is + // still okay to specialize it. + StripImplicitInstantiation(PrevDecl); + return false; + } + // Fall through + + case TSK_ExplicitInstantiationDeclaration: + case TSK_ExplicitInstantiationDefinition: + assert((PrevTSK == TSK_ImplicitInstantiation || + PrevPointOfInstantiation.isValid()) && + "Explicit instantiation without point of instantiation?"); + + // C++ [temp.expl.spec]p6: + // If a template, a member template or the member of a class template + // is explicitly specialized then that specialization shall be declared + // before the first use of that specialization that would cause an + // implicit instantiation to take place, in every translation unit in + // which such a use occurs; no diagnostic is required. + for (Decl *Prev = PrevDecl; Prev; Prev = Prev->getPreviousDecl()) { + // Is there any previous explicit specialization declaration? + if (getTemplateSpecializationKind(Prev) == TSK_ExplicitSpecialization) + return false; + } + + Diag(NewLoc, diag::err_specialization_after_instantiation) + << PrevDecl; + Diag(PrevPointOfInstantiation, diag::note_instantiation_required_here) + << (PrevTSK != TSK_ImplicitInstantiation); + + return true; + } + + case TSK_ExplicitInstantiationDeclaration: + switch (PrevTSK) { + case TSK_ExplicitInstantiationDeclaration: + // This explicit instantiation declaration is redundant (that's okay). + HasNoEffect = true; + return false; + + case TSK_Undeclared: + case TSK_ImplicitInstantiation: + // We're explicitly instantiating something that may have already been + // implicitly instantiated; that's fine. + return false; + + case TSK_ExplicitSpecialization: + // C++0x [temp.explicit]p4: + // For a given set of template parameters, if an explicit instantiation + // of a template appears after a declaration of an explicit + // specialization for that template, the explicit instantiation has no + // effect. + HasNoEffect = true; + return false; + + case TSK_ExplicitInstantiationDefinition: + // C++0x [temp.explicit]p10: + // If an entity is the subject of both an explicit instantiation + // declaration and an explicit instantiation definition in the same + // translation unit, the definition shall follow the declaration. + Diag(NewLoc, + diag::err_explicit_instantiation_declaration_after_definition); + + // Explicit instantiations following a specialization have no effect and + // hence no PrevPointOfInstantiation. In that case, walk decl backwards + // until a valid name loc is found. + Diag(DiagLocForExplicitInstantiation(PrevDecl, PrevPointOfInstantiation), + diag::note_explicit_instantiation_definition_here); + HasNoEffect = true; + return false; + } + + case TSK_ExplicitInstantiationDefinition: + switch (PrevTSK) { + case TSK_Undeclared: + case TSK_ImplicitInstantiation: + // We're explicitly instantiating something that may have already been + // implicitly instantiated; that's fine. + return false; + + case TSK_ExplicitSpecialization: + // C++ DR 259, C++0x [temp.explicit]p4: + // For a given set of template parameters, if an explicit + // instantiation of a template appears after a declaration of + // an explicit specialization for that template, the explicit + // instantiation has no effect. + // + // In C++98/03 mode, we only give an extension warning here, because it + // is not harmful to try to explicitly instantiate something that + // has been explicitly specialized. + Diag(NewLoc, getLangOpts().CPlusPlus0x ? + diag::warn_cxx98_compat_explicit_instantiation_after_specialization : + diag::ext_explicit_instantiation_after_specialization) + << PrevDecl; + Diag(PrevDecl->getLocation(), + diag::note_previous_template_specialization); + HasNoEffect = true; + return false; + + case TSK_ExplicitInstantiationDeclaration: + // We're explicity instantiating a definition for something for which we + // were previously asked to suppress instantiations. That's fine. + + // C++0x [temp.explicit]p4: + // For a given set of template parameters, if an explicit instantiation + // of a template appears after a declaration of an explicit + // specialization for that template, the explicit instantiation has no + // effect. + for (Decl *Prev = PrevDecl; Prev; Prev = Prev->getPreviousDecl()) { + // Is there any previous explicit specialization declaration? + if (getTemplateSpecializationKind(Prev) == TSK_ExplicitSpecialization) { + HasNoEffect = true; + break; + } + } + + return false; + + case TSK_ExplicitInstantiationDefinition: + // C++0x [temp.spec]p5: + // For a given template and a given set of template-arguments, + // - an explicit instantiation definition shall appear at most once + // in a program, + Diag(NewLoc, diag::err_explicit_instantiation_duplicate) + << PrevDecl; + Diag(DiagLocForExplicitInstantiation(PrevDecl, PrevPointOfInstantiation), + diag::note_previous_explicit_instantiation); + HasNoEffect = true; + return false; + } + } + + llvm_unreachable("Missing specialization/instantiation case?"); +} + +/// \brief Perform semantic analysis for the given dependent function +/// template specialization. The only possible way to get a dependent +/// function template specialization is with a friend declaration, +/// like so: +/// +/// template <class T> void foo(T); +/// template <class T> class A { +/// friend void foo<>(T); +/// }; +/// +/// There really isn't any useful analysis we can do here, so we +/// just store the information. +bool +Sema::CheckDependentFunctionTemplateSpecialization(FunctionDecl *FD, + const TemplateArgumentListInfo &ExplicitTemplateArgs, + LookupResult &Previous) { + // Remove anything from Previous that isn't a function template in + // the correct context. + DeclContext *FDLookupContext = FD->getDeclContext()->getRedeclContext(); + LookupResult::Filter F = Previous.makeFilter(); + while (F.hasNext()) { + NamedDecl *D = F.next()->getUnderlyingDecl(); + if (!isa<FunctionTemplateDecl>(D) || + !FDLookupContext->InEnclosingNamespaceSetOf( + D->getDeclContext()->getRedeclContext())) + F.erase(); + } + F.done(); + + // Should this be diagnosed here? + if (Previous.empty()) return true; + + FD->setDependentTemplateSpecialization(Context, Previous.asUnresolvedSet(), + ExplicitTemplateArgs); + return false; +} + +/// \brief Perform semantic analysis for the given function template +/// specialization. +/// +/// This routine performs all of the semantic analysis required for an +/// explicit function template specialization. On successful completion, +/// the function declaration \p FD will become a function template +/// specialization. +/// +/// \param FD the function declaration, which will be updated to become a +/// function template specialization. +/// +/// \param ExplicitTemplateArgs the explicitly-provided template arguments, +/// if any. Note that this may be valid info even when 0 arguments are +/// explicitly provided as in, e.g., \c void sort<>(char*, char*); +/// as it anyway contains info on the angle brackets locations. +/// +/// \param Previous the set of declarations that may be specialized by +/// this function specialization. +bool +Sema::CheckFunctionTemplateSpecialization(FunctionDecl *FD, + TemplateArgumentListInfo *ExplicitTemplateArgs, + LookupResult &Previous) { + // The set of function template specializations that could match this + // explicit function template specialization. + UnresolvedSet<8> Candidates; + + DeclContext *FDLookupContext = FD->getDeclContext()->getRedeclContext(); + for (LookupResult::iterator I = Previous.begin(), E = Previous.end(); + I != E; ++I) { + NamedDecl *Ovl = (*I)->getUnderlyingDecl(); + if (FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(Ovl)) { + // Only consider templates found within the same semantic lookup scope as + // FD. + if (!FDLookupContext->InEnclosingNamespaceSetOf( + Ovl->getDeclContext()->getRedeclContext())) + continue; + + // C++ [temp.expl.spec]p11: + // A trailing template-argument can be left unspecified in the + // template-id naming an explicit function template specialization + // provided it can be deduced from the function argument type. + // Perform template argument deduction to determine whether we may be + // specializing this template. + // FIXME: It is somewhat wasteful to build + TemplateDeductionInfo Info(Context, FD->getLocation()); + FunctionDecl *Specialization = 0; + if (TemplateDeductionResult TDK + = DeduceTemplateArguments(FunTmpl, ExplicitTemplateArgs, + FD->getType(), + Specialization, + Info)) { + // FIXME: Template argument deduction failed; record why it failed, so + // that we can provide nifty diagnostics. + (void)TDK; + continue; + } + + // Record this candidate. + Candidates.addDecl(Specialization, I.getAccess()); + } + } + + // Find the most specialized function template. + UnresolvedSetIterator Result + = getMostSpecialized(Candidates.begin(), Candidates.end(), + TPOC_Other, 0, FD->getLocation(), + PDiag(diag::err_function_template_spec_no_match) + << FD->getDeclName(), + PDiag(diag::err_function_template_spec_ambiguous) + << FD->getDeclName() << (ExplicitTemplateArgs != 0), + PDiag(diag::note_function_template_spec_matched)); + if (Result == Candidates.end()) + return true; + + // Ignore access information; it doesn't figure into redeclaration checking. + FunctionDecl *Specialization = cast<FunctionDecl>(*Result); + + FunctionTemplateSpecializationInfo *SpecInfo + = Specialization->getTemplateSpecializationInfo(); + assert(SpecInfo && "Function template specialization info missing?"); + + // Note: do not overwrite location info if previous template + // specialization kind was explicit. + TemplateSpecializationKind TSK = SpecInfo->getTemplateSpecializationKind(); + if (TSK == TSK_Undeclared || TSK == TSK_ImplicitInstantiation) { + Specialization->setLocation(FD->getLocation()); + // C++11 [dcl.constexpr]p1: An explicit specialization of a constexpr + // function can differ from the template declaration with respect to + // the constexpr specifier. + Specialization->setConstexpr(FD->isConstexpr()); + } + + // FIXME: Check if the prior specialization has a point of instantiation. + // If so, we have run afoul of . + + // If this is a friend declaration, then we're not really declaring + // an explicit specialization. + bool isFriend = (FD->getFriendObjectKind() != Decl::FOK_None); + + // Check the scope of this explicit specialization. + if (!isFriend && + CheckTemplateSpecializationScope(*this, + Specialization->getPrimaryTemplate(), + Specialization, FD->getLocation(), + false)) + return true; + + // C++ [temp.expl.spec]p6: + // If a template, a member template or the member of a class template is + // explicitly specialized then that specialization shall be declared + // before the first use of that specialization that would cause an implicit + // instantiation to take place, in every translation unit in which such a + // use occurs; no diagnostic is required. + bool HasNoEffect = false; + if (!isFriend && + CheckSpecializationInstantiationRedecl(FD->getLocation(), + TSK_ExplicitSpecialization, + Specialization, + SpecInfo->getTemplateSpecializationKind(), + SpecInfo->getPointOfInstantiation(), + HasNoEffect)) + return true; + + // Mark the prior declaration as an explicit specialization, so that later + // clients know that this is an explicit specialization. + if (!isFriend) { + SpecInfo->setTemplateSpecializationKind(TSK_ExplicitSpecialization); + MarkUnusedFileScopedDecl(Specialization); + } + + // Turn the given function declaration into a function template + // specialization, with the template arguments from the previous + // specialization. + // Take copies of (semantic and syntactic) template argument lists. + const TemplateArgumentList* TemplArgs = new (Context) + TemplateArgumentList(Specialization->getTemplateSpecializationArgs()); + FD->setFunctionTemplateSpecialization(Specialization->getPrimaryTemplate(), + TemplArgs, /*InsertPos=*/0, + SpecInfo->getTemplateSpecializationKind(), + ExplicitTemplateArgs); + FD->setStorageClass(Specialization->getStorageClass()); + + // The "previous declaration" for this function template specialization is + // the prior function template specialization. + Previous.clear(); + Previous.addDecl(Specialization); + return false; +} + +/// \brief Perform semantic analysis for the given non-template member +/// specialization. +/// +/// This routine performs all of the semantic analysis required for an +/// explicit member function specialization. On successful completion, +/// the function declaration \p FD will become a member function +/// specialization. +/// +/// \param Member the member declaration, which will be updated to become a +/// specialization. +/// +/// \param Previous the set of declarations, one of which may be specialized +/// by this function specialization; the set will be modified to contain the +/// redeclared member. +bool +Sema::CheckMemberSpecialization(NamedDecl *Member, LookupResult &Previous) { + assert(!isa<TemplateDecl>(Member) && "Only for non-template members"); + + // Try to find the member we are instantiating. + NamedDecl *Instantiation = 0; + NamedDecl *InstantiatedFrom = 0; + MemberSpecializationInfo *MSInfo = 0; + + if (Previous.empty()) { + // Nowhere to look anyway. + } else if (FunctionDecl *Function = dyn_cast<FunctionDecl>(Member)) { + for (LookupResult::iterator I = Previous.begin(), E = Previous.end(); + I != E; ++I) { + NamedDecl *D = (*I)->getUnderlyingDecl(); + if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(D)) { + if (Context.hasSameType(Function->getType(), Method->getType())) { + Instantiation = Method; + InstantiatedFrom = Method->getInstantiatedFromMemberFunction(); + MSInfo = Method->getMemberSpecializationInfo(); + break; + } + } + } + } else if (isa<VarDecl>(Member)) { + VarDecl *PrevVar; + if (Previous.isSingleResult() && + (PrevVar = dyn_cast<VarDecl>(Previous.getFoundDecl()))) + if (PrevVar->isStaticDataMember()) { + Instantiation = PrevVar; + InstantiatedFrom = PrevVar->getInstantiatedFromStaticDataMember(); + MSInfo = PrevVar->getMemberSpecializationInfo(); + } + } else if (isa<RecordDecl>(Member)) { + CXXRecordDecl *PrevRecord; + if (Previous.isSingleResult() && + (PrevRecord = dyn_cast<CXXRecordDecl>(Previous.getFoundDecl()))) { + Instantiation = PrevRecord; + InstantiatedFrom = PrevRecord->getInstantiatedFromMemberClass(); + MSInfo = PrevRecord->getMemberSpecializationInfo(); + } + } else if (isa<EnumDecl>(Member)) { + EnumDecl *PrevEnum; + if (Previous.isSingleResult() && + (PrevEnum = dyn_cast<EnumDecl>(Previous.getFoundDecl()))) { + Instantiation = PrevEnum; + InstantiatedFrom = PrevEnum->getInstantiatedFromMemberEnum(); + MSInfo = PrevEnum->getMemberSpecializationInfo(); + } + } + + if (!Instantiation) { + // There is no previous declaration that matches. Since member + // specializations are always out-of-line, the caller will complain about + // this mismatch later. + return false; + } + + // If this is a friend, just bail out here before we start turning + // things into explicit specializations. + if (Member->getFriendObjectKind() != Decl::FOK_None) { + // Preserve instantiation information. + if (InstantiatedFrom && isa<CXXMethodDecl>(Member)) { + cast<CXXMethodDecl>(Member)->setInstantiationOfMemberFunction( + cast<CXXMethodDecl>(InstantiatedFrom), + cast<CXXMethodDecl>(Instantiation)->getTemplateSpecializationKind()); + } else if (InstantiatedFrom && isa<CXXRecordDecl>(Member)) { + cast<CXXRecordDecl>(Member)->setInstantiationOfMemberClass( + cast<CXXRecordDecl>(InstantiatedFrom), + cast<CXXRecordDecl>(Instantiation)->getTemplateSpecializationKind()); + } + + Previous.clear(); + Previous.addDecl(Instantiation); + return false; + } + + // Make sure that this is a specialization of a member. + if (!InstantiatedFrom) { + Diag(Member->getLocation(), diag::err_spec_member_not_instantiated) + << Member; + Diag(Instantiation->getLocation(), diag::note_specialized_decl); + return true; + } + + // C++ [temp.expl.spec]p6: + // If a template, a member template or the member of a class template is + // explicitly specialized then that specialization shall be declared + // before the first use of that specialization that would cause an implicit + // instantiation to take place, in every translation unit in which such a + // use occurs; no diagnostic is required. + assert(MSInfo && "Member specialization info missing?"); + + bool HasNoEffect = false; + if (CheckSpecializationInstantiationRedecl(Member->getLocation(), + TSK_ExplicitSpecialization, + Instantiation, + MSInfo->getTemplateSpecializationKind(), + MSInfo->getPointOfInstantiation(), + HasNoEffect)) + return true; + + // Check the scope of this explicit specialization. + if (CheckTemplateSpecializationScope(*this, + InstantiatedFrom, + Instantiation, Member->getLocation(), + false)) + return true; + + // Note that this is an explicit instantiation of a member. + // the original declaration to note that it is an explicit specialization + // (if it was previously an implicit instantiation). This latter step + // makes bookkeeping easier. + if (isa<FunctionDecl>(Member)) { + FunctionDecl *InstantiationFunction = cast<FunctionDecl>(Instantiation); + if (InstantiationFunction->getTemplateSpecializationKind() == + TSK_ImplicitInstantiation) { + InstantiationFunction->setTemplateSpecializationKind( + TSK_ExplicitSpecialization); + InstantiationFunction->setLocation(Member->getLocation()); + } + + cast<FunctionDecl>(Member)->setInstantiationOfMemberFunction( + cast<CXXMethodDecl>(InstantiatedFrom), + TSK_ExplicitSpecialization); + MarkUnusedFileScopedDecl(InstantiationFunction); + } else if (isa<VarDecl>(Member)) { + VarDecl *InstantiationVar = cast<VarDecl>(Instantiation); + if (InstantiationVar->getTemplateSpecializationKind() == + TSK_ImplicitInstantiation) { + InstantiationVar->setTemplateSpecializationKind( + TSK_ExplicitSpecialization); + InstantiationVar->setLocation(Member->getLocation()); + } + + Context.setInstantiatedFromStaticDataMember(cast<VarDecl>(Member), + cast<VarDecl>(InstantiatedFrom), + TSK_ExplicitSpecialization); + MarkUnusedFileScopedDecl(InstantiationVar); + } else if (isa<CXXRecordDecl>(Member)) { + CXXRecordDecl *InstantiationClass = cast<CXXRecordDecl>(Instantiation); + if (InstantiationClass->getTemplateSpecializationKind() == + TSK_ImplicitInstantiation) { + InstantiationClass->setTemplateSpecializationKind( + TSK_ExplicitSpecialization); + InstantiationClass->setLocation(Member->getLocation()); + } + + cast<CXXRecordDecl>(Member)->setInstantiationOfMemberClass( + cast<CXXRecordDecl>(InstantiatedFrom), + TSK_ExplicitSpecialization); + } else { + assert(isa<EnumDecl>(Member) && "Only member enums remain"); + EnumDecl *InstantiationEnum = cast<EnumDecl>(Instantiation); + if (InstantiationEnum->getTemplateSpecializationKind() == + TSK_ImplicitInstantiation) { + InstantiationEnum->setTemplateSpecializationKind( + TSK_ExplicitSpecialization); + InstantiationEnum->setLocation(Member->getLocation()); + } + + cast<EnumDecl>(Member)->setInstantiationOfMemberEnum( + cast<EnumDecl>(InstantiatedFrom), TSK_ExplicitSpecialization); + } + + // Save the caller the trouble of having to figure out which declaration + // this specialization matches. + Previous.clear(); + Previous.addDecl(Instantiation); + return false; +} + +/// \brief Check the scope of an explicit instantiation. +/// +/// \returns true if a serious error occurs, false otherwise. +static bool CheckExplicitInstantiationScope(Sema &S, NamedDecl *D, + SourceLocation InstLoc, + bool WasQualifiedName) { + DeclContext *OrigContext= D->getDeclContext()->getEnclosingNamespaceContext(); + DeclContext *CurContext = S.CurContext->getRedeclContext(); + + if (CurContext->isRecord()) { + S.Diag(InstLoc, diag::err_explicit_instantiation_in_class) + << D; + return true; + } + + // C++11 [temp.explicit]p3: + // An explicit instantiation shall appear in an enclosing namespace of its + // template. If the name declared in the explicit instantiation is an + // unqualified name, the explicit instantiation shall appear in the + // namespace where its template is declared or, if that namespace is inline + // (7.3.1), any namespace from its enclosing namespace set. + // + // This is DR275, which we do not retroactively apply to C++98/03. + if (WasQualifiedName) { + if (CurContext->Encloses(OrigContext)) + return false; + } else { + if (CurContext->InEnclosingNamespaceSetOf(OrigContext)) + return false; + } + + if (NamespaceDecl *NS = dyn_cast<NamespaceDecl>(OrigContext)) { + if (WasQualifiedName) + S.Diag(InstLoc, + S.getLangOpts().CPlusPlus0x? + diag::err_explicit_instantiation_out_of_scope : + diag::warn_explicit_instantiation_out_of_scope_0x) + << D << NS; + else + S.Diag(InstLoc, + S.getLangOpts().CPlusPlus0x? + diag::err_explicit_instantiation_unqualified_wrong_namespace : + diag::warn_explicit_instantiation_unqualified_wrong_namespace_0x) + << D << NS; + } else + S.Diag(InstLoc, + S.getLangOpts().CPlusPlus0x? + diag::err_explicit_instantiation_must_be_global : + diag::warn_explicit_instantiation_must_be_global_0x) + << D; + S.Diag(D->getLocation(), diag::note_explicit_instantiation_here); + return false; +} + +/// \brief Determine whether the given scope specifier has a template-id in it. +static bool ScopeSpecifierHasTemplateId(const CXXScopeSpec &SS) { + if (!SS.isSet()) + return false; + + // C++11 [temp.explicit]p3: + // If the explicit instantiation is for a member function, a member class + // or a static data member of a class template specialization, the name of + // the class template specialization in the qualified-id for the member + // name shall be a simple-template-id. + // + // C++98 has the same restriction, just worded differently. + for (NestedNameSpecifier *NNS = (NestedNameSpecifier *)SS.getScopeRep(); + NNS; NNS = NNS->getPrefix()) + if (const Type *T = NNS->getAsType()) + if (isa<TemplateSpecializationType>(T)) + return true; + + return false; +} + +// Explicit instantiation of a class template specialization +DeclResult +Sema::ActOnExplicitInstantiation(Scope *S, + SourceLocation ExternLoc, + SourceLocation TemplateLoc, + unsigned TagSpec, + SourceLocation KWLoc, + const CXXScopeSpec &SS, + TemplateTy TemplateD, + SourceLocation TemplateNameLoc, + SourceLocation LAngleLoc, + ASTTemplateArgsPtr TemplateArgsIn, + SourceLocation RAngleLoc, + AttributeList *Attr) { + // Find the class template we're specializing + TemplateName Name = TemplateD.getAsVal<TemplateName>(); + ClassTemplateDecl *ClassTemplate + = cast<ClassTemplateDecl>(Name.getAsTemplateDecl()); + + // Check that the specialization uses the same tag kind as the + // original template. + TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec); + assert(Kind != TTK_Enum && + "Invalid enum tag in class template explicit instantiation!"); + if (!isAcceptableTagRedeclaration(ClassTemplate->getTemplatedDecl(), + Kind, /*isDefinition*/false, KWLoc, + *ClassTemplate->getIdentifier())) { + Diag(KWLoc, diag::err_use_with_wrong_tag) + << ClassTemplate + << FixItHint::CreateReplacement(KWLoc, + ClassTemplate->getTemplatedDecl()->getKindName()); + Diag(ClassTemplate->getTemplatedDecl()->getLocation(), + diag::note_previous_use); + Kind = ClassTemplate->getTemplatedDecl()->getTagKind(); + } + + // C++0x [temp.explicit]p2: + // There are two forms of explicit instantiation: an explicit instantiation + // definition and an explicit instantiation declaration. An explicit + // instantiation declaration begins with the extern keyword. [...] + TemplateSpecializationKind TSK + = ExternLoc.isInvalid()? TSK_ExplicitInstantiationDefinition + : TSK_ExplicitInstantiationDeclaration; + + // Translate the parser's template argument list in our AST format. + TemplateArgumentListInfo TemplateArgs(LAngleLoc, RAngleLoc); + translateTemplateArguments(TemplateArgsIn, TemplateArgs); + + // Check that the template argument list is well-formed for this + // template. + SmallVector<TemplateArgument, 4> Converted; + if (CheckTemplateArgumentList(ClassTemplate, TemplateNameLoc, + TemplateArgs, false, Converted)) + return true; + + // Find the class template specialization declaration that + // corresponds to these arguments. + void *InsertPos = 0; + ClassTemplateSpecializationDecl *PrevDecl + = ClassTemplate->findSpecialization(Converted.data(), + Converted.size(), InsertPos); + + TemplateSpecializationKind PrevDecl_TSK + = PrevDecl ? PrevDecl->getTemplateSpecializationKind() : TSK_Undeclared; + + // C++0x [temp.explicit]p2: + // [...] An explicit instantiation shall appear in an enclosing + // namespace of its template. [...] + // + // This is C++ DR 275. + if (CheckExplicitInstantiationScope(*this, ClassTemplate, TemplateNameLoc, + SS.isSet())) + return true; + + ClassTemplateSpecializationDecl *Specialization = 0; + + bool HasNoEffect = false; + if (PrevDecl) { + if (CheckSpecializationInstantiationRedecl(TemplateNameLoc, TSK, + PrevDecl, PrevDecl_TSK, + PrevDecl->getPointOfInstantiation(), + HasNoEffect)) + return PrevDecl; + + // Even though HasNoEffect == true means that this explicit instantiation + // has no effect on semantics, we go on to put its syntax in the AST. + + if (PrevDecl_TSK == TSK_ImplicitInstantiation || + PrevDecl_TSK == TSK_Undeclared) { + // Since the only prior class template specialization with these + // arguments was referenced but not declared, reuse that + // declaration node as our own, updating the source location + // for the template name to reflect our new declaration. + // (Other source locations will be updated later.) + Specialization = PrevDecl; + Specialization->setLocation(TemplateNameLoc); + PrevDecl = 0; + } + } + + if (!Specialization) { + // Create a new class template specialization declaration node for + // this explicit specialization. + Specialization + = ClassTemplateSpecializationDecl::Create(Context, Kind, + ClassTemplate->getDeclContext(), + KWLoc, TemplateNameLoc, + ClassTemplate, + Converted.data(), + Converted.size(), + PrevDecl); + SetNestedNameSpecifier(Specialization, SS); + + if (!HasNoEffect && !PrevDecl) { + // Insert the new specialization. + ClassTemplate->AddSpecialization(Specialization, InsertPos); + } + } + + // Build the fully-sugared type for this explicit instantiation as + // the user wrote in the explicit instantiation itself. This means + // that we'll pretty-print the type retrieved from the + // specialization's declaration the way that the user actually wrote + // the explicit instantiation, rather than formatting the name based + // on the "canonical" representation used to store the template + // arguments in the specialization. + TypeSourceInfo *WrittenTy + = Context.getTemplateSpecializationTypeInfo(Name, TemplateNameLoc, + TemplateArgs, + Context.getTypeDeclType(Specialization)); + Specialization->setTypeAsWritten(WrittenTy); + TemplateArgsIn.release(); + + // Set source locations for keywords. + Specialization->setExternLoc(ExternLoc); + Specialization->setTemplateKeywordLoc(TemplateLoc); + + if (Attr) + ProcessDeclAttributeList(S, Specialization, Attr); + + // Add the explicit instantiation into its lexical context. However, + // since explicit instantiations are never found by name lookup, we + // just put it into the declaration context directly. + Specialization->setLexicalDeclContext(CurContext); + CurContext->addDecl(Specialization); + + // Syntax is now OK, so return if it has no other effect on semantics. + if (HasNoEffect) { + // Set the template specialization kind. + Specialization->setTemplateSpecializationKind(TSK); + return Specialization; + } + + // C++ [temp.explicit]p3: + // A definition of a class template or class member template + // shall be in scope at the point of the explicit instantiation of + // the class template or class member template. + // + // This check comes when we actually try to perform the + // instantiation. + ClassTemplateSpecializationDecl *Def + = cast_or_null<ClassTemplateSpecializationDecl>( + Specialization->getDefinition()); + if (!Def) + InstantiateClassTemplateSpecialization(TemplateNameLoc, Specialization, TSK); + else if (TSK == TSK_ExplicitInstantiationDefinition) { + MarkVTableUsed(TemplateNameLoc, Specialization, true); + Specialization->setPointOfInstantiation(Def->getPointOfInstantiation()); + } + + // Instantiate the members of this class template specialization. + Def = cast_or_null<ClassTemplateSpecializationDecl>( + Specialization->getDefinition()); + if (Def) { + TemplateSpecializationKind Old_TSK = Def->getTemplateSpecializationKind(); + + // Fix a TSK_ExplicitInstantiationDeclaration followed by a + // TSK_ExplicitInstantiationDefinition + if (Old_TSK == TSK_ExplicitInstantiationDeclaration && + TSK == TSK_ExplicitInstantiationDefinition) + Def->setTemplateSpecializationKind(TSK); + + InstantiateClassTemplateSpecializationMembers(TemplateNameLoc, Def, TSK); + } + + // Set the template specialization kind. + Specialization->setTemplateSpecializationKind(TSK); + return Specialization; +} + +// Explicit instantiation of a member class of a class template. +DeclResult +Sema::ActOnExplicitInstantiation(Scope *S, + SourceLocation ExternLoc, + SourceLocation TemplateLoc, + unsigned TagSpec, + SourceLocation KWLoc, + CXXScopeSpec &SS, + IdentifierInfo *Name, + SourceLocation NameLoc, + AttributeList *Attr) { + + bool Owned = false; + bool IsDependent = false; + Decl *TagD = ActOnTag(S, TagSpec, Sema::TUK_Reference, + KWLoc, SS, Name, NameLoc, Attr, AS_none, + /*ModulePrivateLoc=*/SourceLocation(), + MultiTemplateParamsArg(*this, 0, 0), + Owned, IsDependent, SourceLocation(), false, + TypeResult()); + assert(!IsDependent && "explicit instantiation of dependent name not yet handled"); + + if (!TagD) + return true; + + TagDecl *Tag = cast<TagDecl>(TagD); + assert(!Tag->isEnum() && "shouldn't see enumerations here"); + + if (Tag->isInvalidDecl()) + return true; + + CXXRecordDecl *Record = cast<CXXRecordDecl>(Tag); + CXXRecordDecl *Pattern = Record->getInstantiatedFromMemberClass(); + if (!Pattern) { + Diag(TemplateLoc, diag::err_explicit_instantiation_nontemplate_type) + << Context.getTypeDeclType(Record); + Diag(Record->getLocation(), diag::note_nontemplate_decl_here); + return true; + } + + // C++0x [temp.explicit]p2: + // If the explicit instantiation is for a class or member class, the + // elaborated-type-specifier in the declaration shall include a + // simple-template-id. + // + // C++98 has the same restriction, just worded differently. + if (!ScopeSpecifierHasTemplateId(SS)) + Diag(TemplateLoc, diag::ext_explicit_instantiation_without_qualified_id) + << Record << SS.getRange(); + + // C++0x [temp.explicit]p2: + // There are two forms of explicit instantiation: an explicit instantiation + // definition and an explicit instantiation declaration. An explicit + // instantiation declaration begins with the extern keyword. [...] + TemplateSpecializationKind TSK + = ExternLoc.isInvalid()? TSK_ExplicitInstantiationDefinition + : TSK_ExplicitInstantiationDeclaration; + + // C++0x [temp.explicit]p2: + // [...] An explicit instantiation shall appear in an enclosing + // namespace of its template. [...] + // + // This is C++ DR 275. + CheckExplicitInstantiationScope(*this, Record, NameLoc, true); + + // Verify that it is okay to explicitly instantiate here. + CXXRecordDecl *PrevDecl + = cast_or_null<CXXRecordDecl>(Record->getPreviousDecl()); + if (!PrevDecl && Record->getDefinition()) + PrevDecl = Record; + if (PrevDecl) { + MemberSpecializationInfo *MSInfo = PrevDecl->getMemberSpecializationInfo(); + bool HasNoEffect = false; + assert(MSInfo && "No member specialization information?"); + if (CheckSpecializationInstantiationRedecl(TemplateLoc, TSK, + PrevDecl, + MSInfo->getTemplateSpecializationKind(), + MSInfo->getPointOfInstantiation(), + HasNoEffect)) + return true; + if (HasNoEffect) + return TagD; + } + + CXXRecordDecl *RecordDef + = cast_or_null<CXXRecordDecl>(Record->getDefinition()); + if (!RecordDef) { + // C++ [temp.explicit]p3: + // A definition of a member class of a class template shall be in scope + // at the point of an explicit instantiation of the member class. + CXXRecordDecl *Def + = cast_or_null<CXXRecordDecl>(Pattern->getDefinition()); + if (!Def) { + Diag(TemplateLoc, diag::err_explicit_instantiation_undefined_member) + << 0 << Record->getDeclName() << Record->getDeclContext(); + Diag(Pattern->getLocation(), diag::note_forward_declaration) + << Pattern; + return true; + } else { + if (InstantiateClass(NameLoc, Record, Def, + getTemplateInstantiationArgs(Record), + TSK)) + return true; + + RecordDef = cast_or_null<CXXRecordDecl>(Record->getDefinition()); + if (!RecordDef) + return true; + } + } + + // Instantiate all of the members of the class. + InstantiateClassMembers(NameLoc, RecordDef, + getTemplateInstantiationArgs(Record), TSK); + + if (TSK == TSK_ExplicitInstantiationDefinition) + MarkVTableUsed(NameLoc, RecordDef, true); + + // FIXME: We don't have any representation for explicit instantiations of + // member classes. Such a representation is not needed for compilation, but it + // should be available for clients that want to see all of the declarations in + // the source code. + return TagD; +} + +DeclResult Sema::ActOnExplicitInstantiation(Scope *S, + SourceLocation ExternLoc, + SourceLocation TemplateLoc, + Declarator &D) { + // Explicit instantiations always require a name. + // TODO: check if/when DNInfo should replace Name. + DeclarationNameInfo NameInfo = GetNameForDeclarator(D); + DeclarationName Name = NameInfo.getName(); + if (!Name) { + if (!D.isInvalidType()) + Diag(D.getDeclSpec().getLocStart(), + diag::err_explicit_instantiation_requires_name) + << D.getDeclSpec().getSourceRange() + << D.getSourceRange(); + + return true; + } + + // The scope passed in may not be a decl scope. Zip up the scope tree until + // we find one that is. + while ((S->getFlags() & Scope::DeclScope) == 0 || + (S->getFlags() & Scope::TemplateParamScope) != 0) + S = S->getParent(); + + // Determine the type of the declaration. + TypeSourceInfo *T = GetTypeForDeclarator(D, S); + QualType R = T->getType(); + if (R.isNull()) + return true; + + // C++ [dcl.stc]p1: + // A storage-class-specifier shall not be specified in [...] an explicit + // instantiation (14.7.2) directive. + if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { + Diag(D.getIdentifierLoc(), diag::err_explicit_instantiation_of_typedef) + << Name; + return true; + } else if (D.getDeclSpec().getStorageClassSpec() + != DeclSpec::SCS_unspecified) { + // Complain about then remove the storage class specifier. + Diag(D.getIdentifierLoc(), diag::err_explicit_instantiation_storage_class) + << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc()); + + D.getMutableDeclSpec().ClearStorageClassSpecs(); + } + + // C++0x [temp.explicit]p1: + // [...] An explicit instantiation of a function template shall not use the + // inline or constexpr specifiers. + // Presumably, this also applies to member functions of class templates as + // well. + if (D.getDeclSpec().isInlineSpecified()) + Diag(D.getDeclSpec().getInlineSpecLoc(), + getLangOpts().CPlusPlus0x ? + diag::err_explicit_instantiation_inline : + diag::warn_explicit_instantiation_inline_0x) + << FixItHint::CreateRemoval(D.getDeclSpec().getInlineSpecLoc()); + if (D.getDeclSpec().isConstexprSpecified()) + // FIXME: Add a fix-it to remove the 'constexpr' and add a 'const' if one is + // not already specified. + Diag(D.getDeclSpec().getConstexprSpecLoc(), + diag::err_explicit_instantiation_constexpr); + + // C++0x [temp.explicit]p2: + // There are two forms of explicit instantiation: an explicit instantiation + // definition and an explicit instantiation declaration. An explicit + // instantiation declaration begins with the extern keyword. [...] + TemplateSpecializationKind TSK + = ExternLoc.isInvalid()? TSK_ExplicitInstantiationDefinition + : TSK_ExplicitInstantiationDeclaration; + + LookupResult Previous(*this, NameInfo, LookupOrdinaryName); + LookupParsedName(Previous, S, &D.getCXXScopeSpec()); + + if (!R->isFunctionType()) { + // C++ [temp.explicit]p1: + // A [...] static data member of a class template can be explicitly + // instantiated from the member definition associated with its class + // template. + if (Previous.isAmbiguous()) + return true; + + VarDecl *Prev = Previous.getAsSingle<VarDecl>(); + if (!Prev || !Prev->isStaticDataMember()) { + // We expect to see a data data member here. + Diag(D.getIdentifierLoc(), diag::err_explicit_instantiation_not_known) + << Name; + for (LookupResult::iterator P = Previous.begin(), PEnd = Previous.end(); + P != PEnd; ++P) + Diag((*P)->getLocation(), diag::note_explicit_instantiation_here); + return true; + } + + if (!Prev->getInstantiatedFromStaticDataMember()) { + // FIXME: Check for explicit specialization? + Diag(D.getIdentifierLoc(), + diag::err_explicit_instantiation_data_member_not_instantiated) + << Prev; + Diag(Prev->getLocation(), diag::note_explicit_instantiation_here); + // FIXME: Can we provide a note showing where this was declared? + return true; + } + + // C++0x [temp.explicit]p2: + // If the explicit instantiation is for a member function, a member class + // or a static data member of a class template specialization, the name of + // the class template specialization in the qualified-id for the member + // name shall be a simple-template-id. + // + // C++98 has the same restriction, just worded differently. + if (!ScopeSpecifierHasTemplateId(D.getCXXScopeSpec())) + Diag(D.getIdentifierLoc(), + diag::ext_explicit_instantiation_without_qualified_id) + << Prev << D.getCXXScopeSpec().getRange(); + + // Check the scope of this explicit instantiation. + CheckExplicitInstantiationScope(*this, Prev, D.getIdentifierLoc(), true); + + // Verify that it is okay to explicitly instantiate here. + MemberSpecializationInfo *MSInfo = Prev->getMemberSpecializationInfo(); + assert(MSInfo && "Missing static data member specialization info?"); + bool HasNoEffect = false; + if (CheckSpecializationInstantiationRedecl(D.getIdentifierLoc(), TSK, Prev, + MSInfo->getTemplateSpecializationKind(), + MSInfo->getPointOfInstantiation(), + HasNoEffect)) + return true; + if (HasNoEffect) + return (Decl*) 0; + + // Instantiate static data member. + Prev->setTemplateSpecializationKind(TSK, D.getIdentifierLoc()); + if (TSK == TSK_ExplicitInstantiationDefinition) + InstantiateStaticDataMemberDefinition(D.getIdentifierLoc(), Prev); + + // FIXME: Create an ExplicitInstantiation node? + return (Decl*) 0; + } + + // If the declarator is a template-id, translate the parser's template + // argument list into our AST format. + bool HasExplicitTemplateArgs = false; + TemplateArgumentListInfo TemplateArgs; + if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) { + TemplateIdAnnotation *TemplateId = D.getName().TemplateId; + TemplateArgs.setLAngleLoc(TemplateId->LAngleLoc); + TemplateArgs.setRAngleLoc(TemplateId->RAngleLoc); + ASTTemplateArgsPtr TemplateArgsPtr(*this, + TemplateId->getTemplateArgs(), + TemplateId->NumArgs); + translateTemplateArguments(TemplateArgsPtr, TemplateArgs); + HasExplicitTemplateArgs = true; + TemplateArgsPtr.release(); + } + + // C++ [temp.explicit]p1: + // A [...] function [...] can be explicitly instantiated from its template. + // A member function [...] of a class template can be explicitly + // instantiated from the member definition associated with its class + // template. + UnresolvedSet<8> Matches; + for (LookupResult::iterator P = Previous.begin(), PEnd = Previous.end(); + P != PEnd; ++P) { + NamedDecl *Prev = *P; + if (!HasExplicitTemplateArgs) { + if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Prev)) { + if (Context.hasSameUnqualifiedType(Method->getType(), R)) { + Matches.clear(); + + Matches.addDecl(Method, P.getAccess()); + if (Method->getTemplateSpecializationKind() == TSK_Undeclared) + break; + } + } + } + + FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(Prev); + if (!FunTmpl) + continue; + + TemplateDeductionInfo Info(Context, D.getIdentifierLoc()); + FunctionDecl *Specialization = 0; + if (TemplateDeductionResult TDK + = DeduceTemplateArguments(FunTmpl, + (HasExplicitTemplateArgs ? &TemplateArgs : 0), + R, Specialization, Info)) { + // FIXME: Keep track of almost-matches? + (void)TDK; + continue; + } + + Matches.addDecl(Specialization, P.getAccess()); + } + + // Find the most specialized function template specialization. + UnresolvedSetIterator Result + = getMostSpecialized(Matches.begin(), Matches.end(), TPOC_Other, 0, + D.getIdentifierLoc(), + PDiag(diag::err_explicit_instantiation_not_known) << Name, + PDiag(diag::err_explicit_instantiation_ambiguous) << Name, + PDiag(diag::note_explicit_instantiation_candidate)); + + if (Result == Matches.end()) + return true; + + // Ignore access control bits, we don't need them for redeclaration checking. + FunctionDecl *Specialization = cast<FunctionDecl>(*Result); + + if (Specialization->getTemplateSpecializationKind() == TSK_Undeclared) { + Diag(D.getIdentifierLoc(), + diag::err_explicit_instantiation_member_function_not_instantiated) + << Specialization + << (Specialization->getTemplateSpecializationKind() == + TSK_ExplicitSpecialization); + Diag(Specialization->getLocation(), diag::note_explicit_instantiation_here); + return true; + } + + FunctionDecl *PrevDecl = Specialization->getPreviousDecl(); + if (!PrevDecl && Specialization->isThisDeclarationADefinition()) + PrevDecl = Specialization; + + if (PrevDecl) { + bool HasNoEffect = false; + if (CheckSpecializationInstantiationRedecl(D.getIdentifierLoc(), TSK, + PrevDecl, + PrevDecl->getTemplateSpecializationKind(), + PrevDecl->getPointOfInstantiation(), + HasNoEffect)) + return true; + + // FIXME: We may still want to build some representation of this + // explicit specialization. + if (HasNoEffect) + return (Decl*) 0; + } + + Specialization->setTemplateSpecializationKind(TSK, D.getIdentifierLoc()); + AttributeList *Attr = D.getDeclSpec().getAttributes().getList(); + if (Attr) + ProcessDeclAttributeList(S, Specialization, Attr); + + if (TSK == TSK_ExplicitInstantiationDefinition) + InstantiateFunctionDefinition(D.getIdentifierLoc(), Specialization); + + // C++0x [temp.explicit]p2: + // If the explicit instantiation is for a member function, a member class + // or a static data member of a class template specialization, the name of + // the class template specialization in the qualified-id for the member + // name shall be a simple-template-id. + // + // C++98 has the same restriction, just worded differently. + FunctionTemplateDecl *FunTmpl = Specialization->getPrimaryTemplate(); + if (D.getName().getKind() != UnqualifiedId::IK_TemplateId && !FunTmpl && + D.getCXXScopeSpec().isSet() && + !ScopeSpecifierHasTemplateId(D.getCXXScopeSpec())) + Diag(D.getIdentifierLoc(), + diag::ext_explicit_instantiation_without_qualified_id) + << Specialization << D.getCXXScopeSpec().getRange(); + + CheckExplicitInstantiationScope(*this, + FunTmpl? (NamedDecl *)FunTmpl + : Specialization->getInstantiatedFromMemberFunction(), + D.getIdentifierLoc(), + D.getCXXScopeSpec().isSet()); + + // FIXME: Create some kind of ExplicitInstantiationDecl here. + return (Decl*) 0; +} + +TypeResult +Sema::ActOnDependentTag(Scope *S, unsigned TagSpec, TagUseKind TUK, + const CXXScopeSpec &SS, IdentifierInfo *Name, + SourceLocation TagLoc, SourceLocation NameLoc) { + // This has to hold, because SS is expected to be defined. + assert(Name && "Expected a name in a dependent tag"); + + NestedNameSpecifier *NNS + = static_cast<NestedNameSpecifier *>(SS.getScopeRep()); + if (!NNS) + return true; + + TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec); + + if (TUK == TUK_Declaration || TUK == TUK_Definition) { + Diag(NameLoc, diag::err_dependent_tag_decl) + << (TUK == TUK_Definition) << Kind << SS.getRange(); + return true; + } + + // Create the resulting type. + ElaboratedTypeKeyword Kwd = TypeWithKeyword::getKeywordForTagTypeKind(Kind); + QualType Result = Context.getDependentNameType(Kwd, NNS, Name); + + // Create type-source location information for this type. + TypeLocBuilder TLB; + DependentNameTypeLoc TL = TLB.push<DependentNameTypeLoc>(Result); + TL.setElaboratedKeywordLoc(TagLoc); + TL.setQualifierLoc(SS.getWithLocInContext(Context)); + TL.setNameLoc(NameLoc); + return CreateParsedType(Result, TLB.getTypeSourceInfo(Context, Result)); +} + +TypeResult +Sema::ActOnTypenameType(Scope *S, SourceLocation TypenameLoc, + const CXXScopeSpec &SS, const IdentifierInfo &II, + SourceLocation IdLoc) { + if (SS.isInvalid()) + return true; + + if (TypenameLoc.isValid() && S && !S->getTemplateParamParent()) + Diag(TypenameLoc, + getLangOpts().CPlusPlus0x ? + diag::warn_cxx98_compat_typename_outside_of_template : + diag::ext_typename_outside_of_template) + << FixItHint::CreateRemoval(TypenameLoc); + + NestedNameSpecifierLoc QualifierLoc = SS.getWithLocInContext(Context); + QualType T = CheckTypenameType(TypenameLoc.isValid()? ETK_Typename : ETK_None, + TypenameLoc, QualifierLoc, II, IdLoc); + if (T.isNull()) + return true; + + TypeSourceInfo *TSI = Context.CreateTypeSourceInfo(T); + if (isa<DependentNameType>(T)) { + DependentNameTypeLoc TL = cast<DependentNameTypeLoc>(TSI->getTypeLoc()); + TL.setElaboratedKeywordLoc(TypenameLoc); + TL.setQualifierLoc(QualifierLoc); + TL.setNameLoc(IdLoc); + } else { + ElaboratedTypeLoc TL = cast<ElaboratedTypeLoc>(TSI->getTypeLoc()); + TL.setElaboratedKeywordLoc(TypenameLoc); + TL.setQualifierLoc(QualifierLoc); + cast<TypeSpecTypeLoc>(TL.getNamedTypeLoc()).setNameLoc(IdLoc); + } + + return CreateParsedType(T, TSI); +} + +TypeResult +Sema::ActOnTypenameType(Scope *S, + SourceLocation TypenameLoc, + const CXXScopeSpec &SS, + SourceLocation TemplateKWLoc, + TemplateTy TemplateIn, + SourceLocation TemplateNameLoc, + SourceLocation LAngleLoc, + ASTTemplateArgsPtr TemplateArgsIn, + SourceLocation RAngleLoc) { + if (TypenameLoc.isValid() && S && !S->getTemplateParamParent()) + Diag(TypenameLoc, + getLangOpts().CPlusPlus0x ? + diag::warn_cxx98_compat_typename_outside_of_template : + diag::ext_typename_outside_of_template) + << FixItHint::CreateRemoval(TypenameLoc); + + // Translate the parser's template argument list in our AST format. + TemplateArgumentListInfo TemplateArgs(LAngleLoc, RAngleLoc); + translateTemplateArguments(TemplateArgsIn, TemplateArgs); + + TemplateName Template = TemplateIn.get(); + if (DependentTemplateName *DTN = Template.getAsDependentTemplateName()) { + // Construct a dependent template specialization type. + assert(DTN && "dependent template has non-dependent name?"); + assert(DTN->getQualifier() + == static_cast<NestedNameSpecifier*>(SS.getScopeRep())); + QualType T = Context.getDependentTemplateSpecializationType(ETK_Typename, + DTN->getQualifier(), + DTN->getIdentifier(), + TemplateArgs); + + // Create source-location information for this type. + TypeLocBuilder Builder; + DependentTemplateSpecializationTypeLoc SpecTL + = Builder.push<DependentTemplateSpecializationTypeLoc>(T); + SpecTL.setElaboratedKeywordLoc(TypenameLoc); + SpecTL.setQualifierLoc(SS.getWithLocInContext(Context)); + SpecTL.setTemplateKeywordLoc(TemplateKWLoc); + SpecTL.setTemplateNameLoc(TemplateNameLoc); + SpecTL.setLAngleLoc(LAngleLoc); + SpecTL.setRAngleLoc(RAngleLoc); + for (unsigned I = 0, N = TemplateArgs.size(); I != N; ++I) + SpecTL.setArgLocInfo(I, TemplateArgs[I].getLocInfo()); + return CreateParsedType(T, Builder.getTypeSourceInfo(Context, T)); + } + + QualType T = CheckTemplateIdType(Template, TemplateNameLoc, TemplateArgs); + if (T.isNull()) + return true; + + // Provide source-location information for the template specialization type. + TypeLocBuilder Builder; + TemplateSpecializationTypeLoc SpecTL + = Builder.push<TemplateSpecializationTypeLoc>(T); + SpecTL.setTemplateKeywordLoc(TemplateKWLoc); + SpecTL.setTemplateNameLoc(TemplateNameLoc); + SpecTL.setLAngleLoc(LAngleLoc); + SpecTL.setRAngleLoc(RAngleLoc); + for (unsigned I = 0, N = TemplateArgs.size(); I != N; ++I) + SpecTL.setArgLocInfo(I, TemplateArgs[I].getLocInfo()); + + T = Context.getElaboratedType(ETK_Typename, SS.getScopeRep(), T); + ElaboratedTypeLoc TL = Builder.push<ElaboratedTypeLoc>(T); + TL.setElaboratedKeywordLoc(TypenameLoc); + TL.setQualifierLoc(SS.getWithLocInContext(Context)); + + TypeSourceInfo *TSI = Builder.getTypeSourceInfo(Context, T); + return CreateParsedType(T, TSI); +} + + +/// \brief Build the type that describes a C++ typename specifier, +/// e.g., "typename T::type". +QualType +Sema::CheckTypenameType(ElaboratedTypeKeyword Keyword, + SourceLocation KeywordLoc, + NestedNameSpecifierLoc QualifierLoc, + const IdentifierInfo &II, + SourceLocation IILoc) { + CXXScopeSpec SS; + SS.Adopt(QualifierLoc); + + DeclContext *Ctx = computeDeclContext(SS); + if (!Ctx) { + // If the nested-name-specifier is dependent and couldn't be + // resolved to a type, build a typename type. + assert(QualifierLoc.getNestedNameSpecifier()->isDependent()); + return Context.getDependentNameType(Keyword, + QualifierLoc.getNestedNameSpecifier(), + &II); + } + + // If the nested-name-specifier refers to the current instantiation, + // the "typename" keyword itself is superfluous. In C++03, the + // program is actually ill-formed. However, DR 382 (in C++0x CD1) + // allows such extraneous "typename" keywords, and we retroactively + // apply this DR to C++03 code with only a warning. In any case we continue. + + if (RequireCompleteDeclContext(SS, Ctx)) + return QualType(); + + DeclarationName Name(&II); + LookupResult Result(*this, Name, IILoc, LookupOrdinaryName); + LookupQualifiedName(Result, Ctx); + unsigned DiagID = 0; + Decl *Referenced = 0; + switch (Result.getResultKind()) { + case LookupResult::NotFound: + DiagID = diag::err_typename_nested_not_found; + break; + + case LookupResult::FoundUnresolvedValue: { + // We found a using declaration that is a value. Most likely, the using + // declaration itself is meant to have the 'typename' keyword. + SourceRange FullRange(KeywordLoc.isValid() ? KeywordLoc : SS.getBeginLoc(), + IILoc); + Diag(IILoc, diag::err_typename_refers_to_using_value_decl) + << Name << Ctx << FullRange; + if (UnresolvedUsingValueDecl *Using + = dyn_cast<UnresolvedUsingValueDecl>(Result.getRepresentativeDecl())){ + SourceLocation Loc = Using->getQualifierLoc().getBeginLoc(); + Diag(Loc, diag::note_using_value_decl_missing_typename) + << FixItHint::CreateInsertion(Loc, "typename "); + } + } + // Fall through to create a dependent typename type, from which we can recover + // better. + + case LookupResult::NotFoundInCurrentInstantiation: + // Okay, it's a member of an unknown instantiation. + return Context.getDependentNameType(Keyword, + QualifierLoc.getNestedNameSpecifier(), + &II); + + case LookupResult::Found: + if (TypeDecl *Type = dyn_cast<TypeDecl>(Result.getFoundDecl())) { + // We found a type. Build an ElaboratedType, since the + // typename-specifier was just sugar. + return Context.getElaboratedType(ETK_Typename, + QualifierLoc.getNestedNameSpecifier(), + Context.getTypeDeclType(Type)); + } + + DiagID = diag::err_typename_nested_not_type; + Referenced = Result.getFoundDecl(); + break; + + case LookupResult::FoundOverloaded: + DiagID = diag::err_typename_nested_not_type; + Referenced = *Result.begin(); + break; + + case LookupResult::Ambiguous: + return QualType(); + } + + // If we get here, it's because name lookup did not find a + // type. Emit an appropriate diagnostic and return an error. + SourceRange FullRange(KeywordLoc.isValid() ? KeywordLoc : SS.getBeginLoc(), + IILoc); + Diag(IILoc, DiagID) << FullRange << Name << Ctx; + if (Referenced) + Diag(Referenced->getLocation(), diag::note_typename_refers_here) + << Name; + return QualType(); +} + +namespace { + // See Sema::RebuildTypeInCurrentInstantiation + class CurrentInstantiationRebuilder + : public TreeTransform<CurrentInstantiationRebuilder> { + SourceLocation Loc; + DeclarationName Entity; + + public: + typedef TreeTransform<CurrentInstantiationRebuilder> inherited; + + CurrentInstantiationRebuilder(Sema &SemaRef, + SourceLocation Loc, + DeclarationName Entity) + : TreeTransform<CurrentInstantiationRebuilder>(SemaRef), + Loc(Loc), Entity(Entity) { } + + /// \brief Determine whether the given type \p T has already been + /// transformed. + /// + /// For the purposes of type reconstruction, a type has already been + /// transformed if it is NULL or if it is not dependent. + bool AlreadyTransformed(QualType T) { + return T.isNull() || !T->isDependentType(); + } + + /// \brief Returns the location of the entity whose type is being + /// rebuilt. + SourceLocation getBaseLocation() { return Loc; } + + /// \brief Returns the name of the entity whose type is being rebuilt. + DeclarationName getBaseEntity() { return Entity; } + + /// \brief Sets the "base" location and entity when that + /// information is known based on another transformation. + void setBase(SourceLocation Loc, DeclarationName Entity) { + this->Loc = Loc; + this->Entity = Entity; + } + + ExprResult TransformLambdaExpr(LambdaExpr *E) { + // Lambdas never need to be transformed. + return E; + } + }; +} + +/// \brief Rebuilds a type within the context of the current instantiation. +/// +/// The type \p T is part of the type of an out-of-line member definition of +/// a class template (or class template partial specialization) that was parsed +/// and constructed before we entered the scope of the class template (or +/// partial specialization thereof). This routine will rebuild that type now +/// that we have entered the declarator's scope, which may produce different +/// canonical types, e.g., +/// +/// \code +/// template<typename T> +/// struct X { +/// typedef T* pointer; +/// pointer data(); +/// }; +/// +/// template<typename T> +/// typename X<T>::pointer X<T>::data() { ... } +/// \endcode +/// +/// Here, the type "typename X<T>::pointer" will be created as a DependentNameType, +/// since we do not know that we can look into X<T> when we parsed the type. +/// This function will rebuild the type, performing the lookup of "pointer" +/// in X<T> and returning an ElaboratedType whose canonical type is the same +/// as the canonical type of T*, allowing the return types of the out-of-line +/// definition and the declaration to match. +TypeSourceInfo *Sema::RebuildTypeInCurrentInstantiation(TypeSourceInfo *T, + SourceLocation Loc, + DeclarationName Name) { + if (!T || !T->getType()->isDependentType()) + return T; + + CurrentInstantiationRebuilder Rebuilder(*this, Loc, Name); + return Rebuilder.TransformType(T); +} + +ExprResult Sema::RebuildExprInCurrentInstantiation(Expr *E) { + CurrentInstantiationRebuilder Rebuilder(*this, E->getExprLoc(), + DeclarationName()); + return Rebuilder.TransformExpr(E); +} + +bool Sema::RebuildNestedNameSpecifierInCurrentInstantiation(CXXScopeSpec &SS) { + if (SS.isInvalid()) + return true; + + NestedNameSpecifierLoc QualifierLoc = SS.getWithLocInContext(Context); + CurrentInstantiationRebuilder Rebuilder(*this, SS.getRange().getBegin(), + DeclarationName()); + NestedNameSpecifierLoc Rebuilt + = Rebuilder.TransformNestedNameSpecifierLoc(QualifierLoc); + if (!Rebuilt) + return true; + + SS.Adopt(Rebuilt); + return false; +} + +/// \brief Rebuild the template parameters now that we know we're in a current +/// instantiation. +bool Sema::RebuildTemplateParamsInCurrentInstantiation( + TemplateParameterList *Params) { + for (unsigned I = 0, N = Params->size(); I != N; ++I) { + Decl *Param = Params->getParam(I); + + // There is nothing to rebuild in a type parameter. + if (isa<TemplateTypeParmDecl>(Param)) + continue; + + // Rebuild the template parameter list of a template template parameter. + if (TemplateTemplateParmDecl *TTP + = dyn_cast<TemplateTemplateParmDecl>(Param)) { + if (RebuildTemplateParamsInCurrentInstantiation( + TTP->getTemplateParameters())) + return true; + + continue; + } + + // Rebuild the type of a non-type template parameter. + NonTypeTemplateParmDecl *NTTP = cast<NonTypeTemplateParmDecl>(Param); + TypeSourceInfo *NewTSI + = RebuildTypeInCurrentInstantiation(NTTP->getTypeSourceInfo(), + NTTP->getLocation(), + NTTP->getDeclName()); + if (!NewTSI) + return true; + + if (NewTSI != NTTP->getTypeSourceInfo()) { + NTTP->setTypeSourceInfo(NewTSI); + NTTP->setType(NewTSI->getType()); + } + } + + return false; +} + +/// \brief Produces a formatted string that describes the binding of +/// template parameters to template arguments. +std::string +Sema::getTemplateArgumentBindingsText(const TemplateParameterList *Params, + const TemplateArgumentList &Args) { + return getTemplateArgumentBindingsText(Params, Args.data(), Args.size()); +} + +std::string +Sema::getTemplateArgumentBindingsText(const TemplateParameterList *Params, + const TemplateArgument *Args, + unsigned NumArgs) { + SmallString<128> Str; + llvm::raw_svector_ostream Out(Str); + + if (!Params || Params->size() == 0 || NumArgs == 0) + return std::string(); + + for (unsigned I = 0, N = Params->size(); I != N; ++I) { + if (I >= NumArgs) + break; + + if (I == 0) + Out << "[with "; + else + Out << ", "; + + if (const IdentifierInfo *Id = Params->getParam(I)->getIdentifier()) { + Out << Id->getName(); + } else { + Out << '$' << I; + } + + Out << " = "; + Args[I].print(getPrintingPolicy(), Out); + } + + Out << ']'; + return Out.str(); +} + +void Sema::MarkAsLateParsedTemplate(FunctionDecl *FD, bool Flag) { + if (!FD) + return; + FD->setLateTemplateParsed(Flag); +} + +bool Sema::IsInsideALocalClassWithinATemplateFunction() { + DeclContext *DC = CurContext; + + while (DC) { + if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(CurContext)) { + const FunctionDecl *FD = RD->isLocalClass(); + return (FD && FD->getTemplatedKind() != FunctionDecl::TK_NonTemplate); + } else if (DC->isTranslationUnit() || DC->isNamespace()) + return false; + + DC = DC->getParent(); + } + return false; +} |
