1 //===--- SemaTemplateInstantiateDecl.cpp - C++ Template Decl Instantiation ===/
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //===----------------------------------------------------------------------===/
9 // This file implements C++ template instantiation for declarations.
11 //===----------------------------------------------------------------------===/
12 #include "clang/Sema/SemaInternal.h"
13 #include "clang/AST/ASTConsumer.h"
14 #include "clang/AST/ASTContext.h"
15 #include "clang/AST/ASTMutationListener.h"
16 #include "clang/AST/DeclTemplate.h"
17 #include "clang/AST/DeclVisitor.h"
18 #include "clang/AST/DependentDiagnostic.h"
19 #include "clang/AST/Expr.h"
20 #include "clang/AST/ExprCXX.h"
21 #include "clang/AST/TypeLoc.h"
22 #include "clang/Sema/Lookup.h"
23 #include "clang/Sema/PrettyDeclStackTrace.h"
24 #include "clang/Sema/Template.h"
26 using namespace clang;
28 static bool isDeclWithinFunction(const Decl *D) {
29 const DeclContext *DC = D->getDeclContext();
30 if (DC->isFunctionOrMethod())
34 return cast<CXXRecordDecl>(DC)->isLocalClass();
39 bool TemplateDeclInstantiator::SubstQualifier(const DeclaratorDecl *OldDecl,
40 DeclaratorDecl *NewDecl) {
41 if (!OldDecl->getQualifierLoc())
44 NestedNameSpecifierLoc NewQualifierLoc
45 = SemaRef.SubstNestedNameSpecifierLoc(OldDecl->getQualifierLoc(),
51 NewDecl->setQualifierInfo(NewQualifierLoc);
55 bool TemplateDeclInstantiator::SubstQualifier(const TagDecl *OldDecl,
57 if (!OldDecl->getQualifierLoc())
60 NestedNameSpecifierLoc NewQualifierLoc
61 = SemaRef.SubstNestedNameSpecifierLoc(OldDecl->getQualifierLoc(),
67 NewDecl->setQualifierInfo(NewQualifierLoc);
71 // Include attribute instantiation code.
72 #include "clang/Sema/AttrTemplateInstantiate.inc"
74 static void instantiateDependentAlignedAttr(
75 Sema &S, const MultiLevelTemplateArgumentList &TemplateArgs,
76 const AlignedAttr *Aligned, Decl *New, bool IsPackExpansion) {
77 if (Aligned->isAlignmentExpr()) {
78 // The alignment expression is a constant expression.
79 EnterExpressionEvaluationContext Unevaluated(S, Sema::ConstantEvaluated);
80 ExprResult Result = S.SubstExpr(Aligned->getAlignmentExpr(), TemplateArgs);
81 if (!Result.isInvalid())
82 S.AddAlignedAttr(Aligned->getLocation(), New, Result.getAs<Expr>(),
83 Aligned->getSpellingListIndex(), IsPackExpansion);
85 TypeSourceInfo *Result = S.SubstType(Aligned->getAlignmentType(),
86 TemplateArgs, Aligned->getLocation(),
89 S.AddAlignedAttr(Aligned->getLocation(), New, Result,
90 Aligned->getSpellingListIndex(), IsPackExpansion);
94 static void instantiateDependentAlignedAttr(
95 Sema &S, const MultiLevelTemplateArgumentList &TemplateArgs,
96 const AlignedAttr *Aligned, Decl *New) {
97 if (!Aligned->isPackExpansion()) {
98 instantiateDependentAlignedAttr(S, TemplateArgs, Aligned, New, false);
102 SmallVector<UnexpandedParameterPack, 2> Unexpanded;
103 if (Aligned->isAlignmentExpr())
104 S.collectUnexpandedParameterPacks(Aligned->getAlignmentExpr(),
107 S.collectUnexpandedParameterPacks(Aligned->getAlignmentType()->getTypeLoc(),
109 assert(!Unexpanded.empty() && "Pack expansion without parameter packs?");
111 // Determine whether we can expand this attribute pack yet.
112 bool Expand = true, RetainExpansion = false;
113 Optional<unsigned> NumExpansions;
114 // FIXME: Use the actual location of the ellipsis.
115 SourceLocation EllipsisLoc = Aligned->getLocation();
116 if (S.CheckParameterPacksForExpansion(EllipsisLoc, Aligned->getRange(),
117 Unexpanded, TemplateArgs, Expand,
118 RetainExpansion, NumExpansions))
122 Sema::ArgumentPackSubstitutionIndexRAII SubstIndex(S, -1);
123 instantiateDependentAlignedAttr(S, TemplateArgs, Aligned, New, true);
125 for (unsigned I = 0; I != *NumExpansions; ++I) {
126 Sema::ArgumentPackSubstitutionIndexRAII SubstIndex(S, I);
127 instantiateDependentAlignedAttr(S, TemplateArgs, Aligned, New, false);
132 static void instantiateDependentEnableIfAttr(
133 Sema &S, const MultiLevelTemplateArgumentList &TemplateArgs,
134 const EnableIfAttr *A, const Decl *Tmpl, Decl *New) {
135 Expr *Cond = nullptr;
137 EnterExpressionEvaluationContext Unevaluated(S, Sema::Unevaluated);
138 ExprResult Result = S.SubstExpr(A->getCond(), TemplateArgs);
139 if (Result.isInvalid())
141 Cond = Result.getAs<Expr>();
143 if (A->getCond()->isTypeDependent() && !Cond->isTypeDependent()) {
144 ExprResult Converted = S.PerformContextuallyConvertToBool(Cond);
145 if (Converted.isInvalid())
147 Cond = Converted.get();
150 SmallVector<PartialDiagnosticAt, 8> Diags;
151 if (A->getCond()->isValueDependent() && !Cond->isValueDependent() &&
152 !Expr::isPotentialConstantExprUnevaluated(Cond, cast<FunctionDecl>(Tmpl),
154 S.Diag(A->getLocation(), diag::err_enable_if_never_constant_expr);
155 for (int I = 0, N = Diags.size(); I != N; ++I)
156 S.Diag(Diags[I].first, Diags[I].second);
160 EnableIfAttr *EIA = new (S.getASTContext())
161 EnableIfAttr(A->getLocation(), S.getASTContext(), Cond,
163 A->getSpellingListIndex());
167 void Sema::InstantiateAttrs(const MultiLevelTemplateArgumentList &TemplateArgs,
168 const Decl *Tmpl, Decl *New,
169 LateInstantiatedAttrVec *LateAttrs,
170 LocalInstantiationScope *OuterMostScope) {
171 for (const auto *TmplAttr : Tmpl->attrs()) {
172 // FIXME: This should be generalized to more than just the AlignedAttr.
173 const AlignedAttr *Aligned = dyn_cast<AlignedAttr>(TmplAttr);
174 if (Aligned && Aligned->isAlignmentDependent()) {
175 instantiateDependentAlignedAttr(*this, TemplateArgs, Aligned, New);
179 const EnableIfAttr *EnableIf = dyn_cast<EnableIfAttr>(TmplAttr);
180 if (EnableIf && EnableIf->getCond()->isValueDependent()) {
181 instantiateDependentEnableIfAttr(*this, TemplateArgs, EnableIf, Tmpl,
186 assert(!TmplAttr->isPackExpansion());
187 if (TmplAttr->isLateParsed() && LateAttrs) {
188 // Late parsed attributes must be instantiated and attached after the
189 // enclosing class has been instantiated. See Sema::InstantiateClass.
190 LocalInstantiationScope *Saved = nullptr;
191 if (CurrentInstantiationScope)
192 Saved = CurrentInstantiationScope->cloneScopes(OuterMostScope);
193 LateAttrs->push_back(LateInstantiatedAttribute(TmplAttr, Saved, New));
195 // Allow 'this' within late-parsed attributes.
196 NamedDecl *ND = dyn_cast<NamedDecl>(New);
197 CXXRecordDecl *ThisContext =
198 dyn_cast_or_null<CXXRecordDecl>(ND->getDeclContext());
199 CXXThisScopeRAII ThisScope(*this, ThisContext, /*TypeQuals*/0,
200 ND && ND->isCXXInstanceMember());
202 Attr *NewAttr = sema::instantiateTemplateAttribute(TmplAttr, Context,
203 *this, TemplateArgs);
205 New->addAttr(NewAttr);
211 TemplateDeclInstantiator::VisitTranslationUnitDecl(TranslationUnitDecl *D) {
212 llvm_unreachable("Translation units cannot be instantiated");
216 TemplateDeclInstantiator::VisitLabelDecl(LabelDecl *D) {
217 LabelDecl *Inst = LabelDecl::Create(SemaRef.Context, Owner, D->getLocation(),
219 Owner->addDecl(Inst);
224 TemplateDeclInstantiator::VisitNamespaceDecl(NamespaceDecl *D) {
225 llvm_unreachable("Namespaces cannot be instantiated");
229 TemplateDeclInstantiator::VisitNamespaceAliasDecl(NamespaceAliasDecl *D) {
230 NamespaceAliasDecl *Inst
231 = NamespaceAliasDecl::Create(SemaRef.Context, Owner,
232 D->getNamespaceLoc(),
235 D->getQualifierLoc(),
236 D->getTargetNameLoc(),
238 Owner->addDecl(Inst);
242 Decl *TemplateDeclInstantiator::InstantiateTypedefNameDecl(TypedefNameDecl *D,
244 bool Invalid = false;
245 TypeSourceInfo *DI = D->getTypeSourceInfo();
246 if (DI->getType()->isInstantiationDependentType() ||
247 DI->getType()->isVariablyModifiedType()) {
248 DI = SemaRef.SubstType(DI, TemplateArgs,
249 D->getLocation(), D->getDeclName());
252 DI = SemaRef.Context.getTrivialTypeSourceInfo(SemaRef.Context.IntTy);
255 SemaRef.MarkDeclarationsReferencedInType(D->getLocation(), DI->getType());
258 // HACK: g++ has a bug where it gets the value kind of ?: wrong.
259 // libstdc++ relies upon this bug in its implementation of common_type.
260 // If we happen to be processing that implementation, fake up the g++ ?:
261 // semantics. See LWG issue 2141 for more information on the bug.
262 const DecltypeType *DT = DI->getType()->getAs<DecltypeType>();
263 CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(D->getDeclContext());
264 if (DT && RD && isa<ConditionalOperator>(DT->getUnderlyingExpr()) &&
265 DT->isReferenceType() &&
266 RD->getEnclosingNamespaceContext() == SemaRef.getStdNamespace() &&
267 RD->getIdentifier() && RD->getIdentifier()->isStr("common_type") &&
268 D->getIdentifier() && D->getIdentifier()->isStr("type") &&
269 SemaRef.getSourceManager().isInSystemHeader(D->getLocStart()))
270 // Fold it to the (non-reference) type which g++ would have produced.
271 DI = SemaRef.Context.getTrivialTypeSourceInfo(
272 DI->getType().getNonReferenceType());
274 // Create the new typedef
275 TypedefNameDecl *Typedef;
277 Typedef = TypeAliasDecl::Create(SemaRef.Context, Owner, D->getLocStart(),
278 D->getLocation(), D->getIdentifier(), DI);
280 Typedef = TypedefDecl::Create(SemaRef.Context, Owner, D->getLocStart(),
281 D->getLocation(), D->getIdentifier(), DI);
283 Typedef->setInvalidDecl();
285 // If the old typedef was the name for linkage purposes of an anonymous
286 // tag decl, re-establish that relationship for the new typedef.
287 if (const TagType *oldTagType = D->getUnderlyingType()->getAs<TagType>()) {
288 TagDecl *oldTag = oldTagType->getDecl();
289 if (oldTag->getTypedefNameForAnonDecl() == D && !Invalid) {
290 TagDecl *newTag = DI->getType()->castAs<TagType>()->getDecl();
291 assert(!newTag->hasNameForLinkage());
292 newTag->setTypedefNameForAnonDecl(Typedef);
296 if (TypedefNameDecl *Prev = D->getPreviousDecl()) {
297 NamedDecl *InstPrev = SemaRef.FindInstantiatedDecl(D->getLocation(), Prev,
302 TypedefNameDecl *InstPrevTypedef = cast<TypedefNameDecl>(InstPrev);
304 // If the typedef types are not identical, reject them.
305 SemaRef.isIncompatibleTypedef(InstPrevTypedef, Typedef);
307 Typedef->setPreviousDecl(InstPrevTypedef);
310 SemaRef.InstantiateAttrs(TemplateArgs, D, Typedef);
312 Typedef->setAccess(D->getAccess());
317 Decl *TemplateDeclInstantiator::VisitTypedefDecl(TypedefDecl *D) {
318 Decl *Typedef = InstantiateTypedefNameDecl(D, /*IsTypeAlias=*/false);
319 Owner->addDecl(Typedef);
323 Decl *TemplateDeclInstantiator::VisitTypeAliasDecl(TypeAliasDecl *D) {
324 Decl *Typedef = InstantiateTypedefNameDecl(D, /*IsTypeAlias=*/true);
325 Owner->addDecl(Typedef);
330 TemplateDeclInstantiator::VisitTypeAliasTemplateDecl(TypeAliasTemplateDecl *D) {
331 // Create a local instantiation scope for this type alias template, which
332 // will contain the instantiations of the template parameters.
333 LocalInstantiationScope Scope(SemaRef);
335 TemplateParameterList *TempParams = D->getTemplateParameters();
336 TemplateParameterList *InstParams = SubstTemplateParams(TempParams);
340 TypeAliasDecl *Pattern = D->getTemplatedDecl();
342 TypeAliasTemplateDecl *PrevAliasTemplate = nullptr;
343 if (Pattern->getPreviousDecl()) {
344 DeclContext::lookup_result Found = Owner->lookup(Pattern->getDeclName());
345 if (!Found.empty()) {
346 PrevAliasTemplate = dyn_cast<TypeAliasTemplateDecl>(Found.front());
350 TypeAliasDecl *AliasInst = cast_or_null<TypeAliasDecl>(
351 InstantiateTypedefNameDecl(Pattern, /*IsTypeAlias=*/true));
355 TypeAliasTemplateDecl *Inst
356 = TypeAliasTemplateDecl::Create(SemaRef.Context, Owner, D->getLocation(),
357 D->getDeclName(), InstParams, AliasInst);
358 if (PrevAliasTemplate)
359 Inst->setPreviousDecl(PrevAliasTemplate);
361 Inst->setAccess(D->getAccess());
363 if (!PrevAliasTemplate)
364 Inst->setInstantiatedFromMemberTemplate(D);
366 Owner->addDecl(Inst);
371 Decl *TemplateDeclInstantiator::VisitVarDecl(VarDecl *D) {
372 return VisitVarDecl(D, /*InstantiatingVarTemplate=*/false);
375 Decl *TemplateDeclInstantiator::VisitVarDecl(VarDecl *D,
376 bool InstantiatingVarTemplate) {
378 // If this is the variable for an anonymous struct or union,
379 // instantiate the anonymous struct/union type first.
380 if (const RecordType *RecordTy = D->getType()->getAs<RecordType>())
381 if (RecordTy->getDecl()->isAnonymousStructOrUnion())
382 if (!VisitCXXRecordDecl(cast<CXXRecordDecl>(RecordTy->getDecl())))
385 // Do substitution on the type of the declaration
386 TypeSourceInfo *DI = SemaRef.SubstType(D->getTypeSourceInfo(),
388 D->getTypeSpecStartLoc(),
393 if (DI->getType()->isFunctionType()) {
394 SemaRef.Diag(D->getLocation(), diag::err_variable_instantiates_to_function)
395 << D->isStaticDataMember() << DI->getType();
399 DeclContext *DC = Owner;
400 if (D->isLocalExternDecl())
401 SemaRef.adjustContextForLocalExternDecl(DC);
403 // Build the instantiated declaration.
404 VarDecl *Var = VarDecl::Create(SemaRef.Context, DC, D->getInnerLocStart(),
405 D->getLocation(), D->getIdentifier(),
406 DI->getType(), DI, D->getStorageClass());
408 // In ARC, infer 'retaining' for variables of retainable type.
409 if (SemaRef.getLangOpts().ObjCAutoRefCount &&
410 SemaRef.inferObjCARCLifetime(Var))
411 Var->setInvalidDecl();
413 // Substitute the nested name specifier, if any.
414 if (SubstQualifier(D, Var))
417 SemaRef.BuildVariableInstantiation(Var, D, TemplateArgs, LateAttrs, Owner,
418 StartingScope, InstantiatingVarTemplate);
420 if (D->isNRVOVariable()) {
421 QualType ReturnType = cast<FunctionDecl>(DC)->getReturnType();
422 if (SemaRef.isCopyElisionCandidate(ReturnType, Var, false))
423 Var->setNRVOVariable(true);
426 Var->setImplicit(D->isImplicit());
431 Decl *TemplateDeclInstantiator::VisitAccessSpecDecl(AccessSpecDecl *D) {
433 = AccessSpecDecl::Create(SemaRef.Context, D->getAccess(), Owner,
434 D->getAccessSpecifierLoc(), D->getColonLoc());
435 Owner->addHiddenDecl(AD);
439 Decl *TemplateDeclInstantiator::VisitFieldDecl(FieldDecl *D) {
440 bool Invalid = false;
441 TypeSourceInfo *DI = D->getTypeSourceInfo();
442 if (DI->getType()->isInstantiationDependentType() ||
443 DI->getType()->isVariablyModifiedType()) {
444 DI = SemaRef.SubstType(DI, TemplateArgs,
445 D->getLocation(), D->getDeclName());
447 DI = D->getTypeSourceInfo();
449 } else if (DI->getType()->isFunctionType()) {
450 // C++ [temp.arg.type]p3:
451 // If a declaration acquires a function type through a type
452 // dependent on a template-parameter and this causes a
453 // declaration that does not use the syntactic form of a
454 // function declarator to have function type, the program is
456 SemaRef.Diag(D->getLocation(), diag::err_field_instantiates_to_function)
461 SemaRef.MarkDeclarationsReferencedInType(D->getLocation(), DI->getType());
464 Expr *BitWidth = D->getBitWidth();
468 // The bit-width expression is a constant expression.
469 EnterExpressionEvaluationContext Unevaluated(SemaRef,
470 Sema::ConstantEvaluated);
472 ExprResult InstantiatedBitWidth
473 = SemaRef.SubstExpr(BitWidth, TemplateArgs);
474 if (InstantiatedBitWidth.isInvalid()) {
478 BitWidth = InstantiatedBitWidth.getAs<Expr>();
481 FieldDecl *Field = SemaRef.CheckFieldDecl(D->getDeclName(),
483 cast<RecordDecl>(Owner),
487 D->getInClassInitStyle(),
488 D->getInnerLocStart(),
492 cast<Decl>(Owner)->setInvalidDecl();
496 SemaRef.InstantiateAttrs(TemplateArgs, D, Field, LateAttrs, StartingScope);
498 if (Field->hasAttrs())
499 SemaRef.CheckAlignasUnderalignment(Field);
502 Field->setInvalidDecl();
504 if (!Field->getDeclName()) {
505 // Keep track of where this decl came from.
506 SemaRef.Context.setInstantiatedFromUnnamedFieldDecl(Field, D);
508 if (CXXRecordDecl *Parent= dyn_cast<CXXRecordDecl>(Field->getDeclContext())) {
509 if (Parent->isAnonymousStructOrUnion() &&
510 Parent->getRedeclContext()->isFunctionOrMethod())
511 SemaRef.CurrentInstantiationScope->InstantiatedLocal(D, Field);
514 Field->setImplicit(D->isImplicit());
515 Field->setAccess(D->getAccess());
516 Owner->addDecl(Field);
521 Decl *TemplateDeclInstantiator::VisitMSPropertyDecl(MSPropertyDecl *D) {
522 bool Invalid = false;
523 TypeSourceInfo *DI = D->getTypeSourceInfo();
525 if (DI->getType()->isVariablyModifiedType()) {
526 SemaRef.Diag(D->getLocation(), diag::err_property_is_variably_modified)
529 } else if (DI->getType()->isInstantiationDependentType()) {
530 DI = SemaRef.SubstType(DI, TemplateArgs,
531 D->getLocation(), D->getDeclName());
533 DI = D->getTypeSourceInfo();
535 } else if (DI->getType()->isFunctionType()) {
536 // C++ [temp.arg.type]p3:
537 // If a declaration acquires a function type through a type
538 // dependent on a template-parameter and this causes a
539 // declaration that does not use the syntactic form of a
540 // function declarator to have function type, the program is
542 SemaRef.Diag(D->getLocation(), diag::err_field_instantiates_to_function)
547 SemaRef.MarkDeclarationsReferencedInType(D->getLocation(), DI->getType());
550 MSPropertyDecl *Property = MSPropertyDecl::Create(
551 SemaRef.Context, Owner, D->getLocation(), D->getDeclName(), DI->getType(),
552 DI, D->getLocStart(), D->getGetterId(), D->getSetterId());
554 SemaRef.InstantiateAttrs(TemplateArgs, D, Property, LateAttrs,
558 Property->setInvalidDecl();
560 Property->setAccess(D->getAccess());
561 Owner->addDecl(Property);
566 Decl *TemplateDeclInstantiator::VisitIndirectFieldDecl(IndirectFieldDecl *D) {
567 NamedDecl **NamedChain =
568 new (SemaRef.Context)NamedDecl*[D->getChainingSize()];
571 for (auto *PI : D->chain()) {
572 NamedDecl *Next = SemaRef.FindInstantiatedDecl(D->getLocation(), PI,
577 NamedChain[i++] = Next;
580 QualType T = cast<FieldDecl>(NamedChain[i-1])->getType();
581 IndirectFieldDecl* IndirectField
582 = IndirectFieldDecl::Create(SemaRef.Context, Owner, D->getLocation(),
583 D->getIdentifier(), T,
584 NamedChain, D->getChainingSize());
587 IndirectField->setImplicit(D->isImplicit());
588 IndirectField->setAccess(D->getAccess());
589 Owner->addDecl(IndirectField);
590 return IndirectField;
593 Decl *TemplateDeclInstantiator::VisitFriendDecl(FriendDecl *D) {
594 // Handle friend type expressions by simply substituting template
595 // parameters into the pattern type and checking the result.
596 if (TypeSourceInfo *Ty = D->getFriendType()) {
597 TypeSourceInfo *InstTy;
598 // If this is an unsupported friend, don't bother substituting template
599 // arguments into it. The actual type referred to won't be used by any
600 // parts of Clang, and may not be valid for instantiating. Just use the
601 // same info for the instantiated friend.
602 if (D->isUnsupportedFriend()) {
605 InstTy = SemaRef.SubstType(Ty, TemplateArgs,
606 D->getLocation(), DeclarationName());
611 FriendDecl *FD = SemaRef.CheckFriendTypeDecl(D->getLocStart(),
612 D->getFriendLoc(), InstTy);
616 FD->setAccess(AS_public);
617 FD->setUnsupportedFriend(D->isUnsupportedFriend());
622 NamedDecl *ND = D->getFriendDecl();
623 assert(ND && "friend decl must be a decl or a type!");
625 // All of the Visit implementations for the various potential friend
626 // declarations have to be carefully written to work for friend
627 // objects, with the most important detail being that the target
628 // decl should almost certainly not be placed in Owner.
629 Decl *NewND = Visit(ND);
630 if (!NewND) return nullptr;
633 FriendDecl::Create(SemaRef.Context, Owner, D->getLocation(),
634 cast<NamedDecl>(NewND), D->getFriendLoc());
635 FD->setAccess(AS_public);
636 FD->setUnsupportedFriend(D->isUnsupportedFriend());
641 Decl *TemplateDeclInstantiator::VisitStaticAssertDecl(StaticAssertDecl *D) {
642 Expr *AssertExpr = D->getAssertExpr();
644 // The expression in a static assertion is a constant expression.
645 EnterExpressionEvaluationContext Unevaluated(SemaRef,
646 Sema::ConstantEvaluated);
648 ExprResult InstantiatedAssertExpr
649 = SemaRef.SubstExpr(AssertExpr, TemplateArgs);
650 if (InstantiatedAssertExpr.isInvalid())
653 return SemaRef.BuildStaticAssertDeclaration(D->getLocation(),
654 InstantiatedAssertExpr.get(),
660 Decl *TemplateDeclInstantiator::VisitEnumDecl(EnumDecl *D) {
661 EnumDecl *PrevDecl = nullptr;
662 if (D->getPreviousDecl()) {
663 NamedDecl *Prev = SemaRef.FindInstantiatedDecl(D->getLocation(),
664 D->getPreviousDecl(),
666 if (!Prev) return nullptr;
667 PrevDecl = cast<EnumDecl>(Prev);
670 EnumDecl *Enum = EnumDecl::Create(SemaRef.Context, Owner, D->getLocStart(),
671 D->getLocation(), D->getIdentifier(),
672 PrevDecl, D->isScoped(),
673 D->isScopedUsingClassTag(), D->isFixed());
675 if (TypeSourceInfo *TI = D->getIntegerTypeSourceInfo()) {
676 // If we have type source information for the underlying type, it means it
677 // has been explicitly set by the user. Perform substitution on it before
679 SourceLocation UnderlyingLoc = TI->getTypeLoc().getBeginLoc();
680 TypeSourceInfo *NewTI = SemaRef.SubstType(TI, TemplateArgs, UnderlyingLoc,
682 if (!NewTI || SemaRef.CheckEnumUnderlyingType(NewTI))
683 Enum->setIntegerType(SemaRef.Context.IntTy);
685 Enum->setIntegerTypeSourceInfo(NewTI);
687 assert(!D->getIntegerType()->isDependentType()
688 && "Dependent type without type source info");
689 Enum->setIntegerType(D->getIntegerType());
693 SemaRef.InstantiateAttrs(TemplateArgs, D, Enum);
695 Enum->setInstantiationOfMemberEnum(D, TSK_ImplicitInstantiation);
696 Enum->setAccess(D->getAccess());
697 // Forward the mangling number from the template to the instantiated decl.
698 SemaRef.Context.setManglingNumber(Enum, SemaRef.Context.getManglingNumber(D));
699 if (SubstQualifier(D, Enum)) return nullptr;
700 Owner->addDecl(Enum);
702 EnumDecl *Def = D->getDefinition();
703 if (Def && Def != D) {
704 // If this is an out-of-line definition of an enum member template, check
705 // that the underlying types match in the instantiation of both
707 if (TypeSourceInfo *TI = Def->getIntegerTypeSourceInfo()) {
708 SourceLocation UnderlyingLoc = TI->getTypeLoc().getBeginLoc();
709 QualType DefnUnderlying =
710 SemaRef.SubstType(TI->getType(), TemplateArgs,
711 UnderlyingLoc, DeclarationName());
712 SemaRef.CheckEnumRedeclaration(Def->getLocation(), Def->isScoped(),
713 DefnUnderlying, Enum);
717 // C++11 [temp.inst]p1: The implicit instantiation of a class template
718 // specialization causes the implicit instantiation of the declarations, but
719 // not the definitions of scoped member enumerations.
721 // DR1484 clarifies that enumeration definitions inside of a template
722 // declaration aren't considered entities that can be separately instantiated
723 // from the rest of the entity they are declared inside of.
724 if (isDeclWithinFunction(D) ? D == Def : Def && !Enum->isScoped()) {
725 SemaRef.CurrentInstantiationScope->InstantiatedLocal(D, Enum);
726 InstantiateEnumDefinition(Enum, Def);
732 void TemplateDeclInstantiator::InstantiateEnumDefinition(
733 EnumDecl *Enum, EnumDecl *Pattern) {
734 Enum->startDefinition();
736 // Update the location to refer to the definition.
737 Enum->setLocation(Pattern->getLocation());
739 SmallVector<Decl*, 4> Enumerators;
741 EnumConstantDecl *LastEnumConst = nullptr;
742 for (auto *EC : Pattern->enumerators()) {
743 // The specified value for the enumerator.
744 ExprResult Value((Expr *)nullptr);
745 if (Expr *UninstValue = EC->getInitExpr()) {
746 // The enumerator's value expression is a constant expression.
747 EnterExpressionEvaluationContext Unevaluated(SemaRef,
748 Sema::ConstantEvaluated);
750 Value = SemaRef.SubstExpr(UninstValue, TemplateArgs);
753 // Drop the initial value and continue.
754 bool isInvalid = false;
755 if (Value.isInvalid()) {
760 EnumConstantDecl *EnumConst
761 = SemaRef.CheckEnumConstant(Enum, LastEnumConst,
762 EC->getLocation(), EC->getIdentifier(),
767 EnumConst->setInvalidDecl();
768 Enum->setInvalidDecl();
772 SemaRef.InstantiateAttrs(TemplateArgs, EC, EnumConst);
774 EnumConst->setAccess(Enum->getAccess());
775 Enum->addDecl(EnumConst);
776 Enumerators.push_back(EnumConst);
777 LastEnumConst = EnumConst;
779 if (Pattern->getDeclContext()->isFunctionOrMethod() &&
781 // If the enumeration is within a function or method, record the enum
782 // constant as a local.
783 SemaRef.CurrentInstantiationScope->InstantiatedLocal(EC, EnumConst);
788 // FIXME: Fixup LBraceLoc
789 SemaRef.ActOnEnumBody(Enum->getLocation(), SourceLocation(),
790 Enum->getRBraceLoc(), Enum,
795 Decl *TemplateDeclInstantiator::VisitEnumConstantDecl(EnumConstantDecl *D) {
796 llvm_unreachable("EnumConstantDecls can only occur within EnumDecls.");
799 Decl *TemplateDeclInstantiator::VisitClassTemplateDecl(ClassTemplateDecl *D) {
800 bool isFriend = (D->getFriendObjectKind() != Decl::FOK_None);
802 // Create a local instantiation scope for this class template, which
803 // will contain the instantiations of the template parameters.
804 LocalInstantiationScope Scope(SemaRef);
805 TemplateParameterList *TempParams = D->getTemplateParameters();
806 TemplateParameterList *InstParams = SubstTemplateParams(TempParams);
810 CXXRecordDecl *Pattern = D->getTemplatedDecl();
812 // Instantiate the qualifier. We have to do this first in case
813 // we're a friend declaration, because if we are then we need to put
814 // the new declaration in the appropriate context.
815 NestedNameSpecifierLoc QualifierLoc = Pattern->getQualifierLoc();
817 QualifierLoc = SemaRef.SubstNestedNameSpecifierLoc(QualifierLoc,
823 CXXRecordDecl *PrevDecl = nullptr;
824 ClassTemplateDecl *PrevClassTemplate = nullptr;
826 if (!isFriend && Pattern->getPreviousDecl()) {
827 DeclContext::lookup_result Found = Owner->lookup(Pattern->getDeclName());
828 if (!Found.empty()) {
829 PrevClassTemplate = dyn_cast<ClassTemplateDecl>(Found.front());
830 if (PrevClassTemplate)
831 PrevDecl = PrevClassTemplate->getTemplatedDecl();
835 // If this isn't a friend, then it's a member template, in which
836 // case we just want to build the instantiation in the
837 // specialization. If it is a friend, we want to build it in
838 // the appropriate context.
839 DeclContext *DC = Owner;
843 SS.Adopt(QualifierLoc);
844 DC = SemaRef.computeDeclContext(SS);
845 if (!DC) return nullptr;
847 DC = SemaRef.FindInstantiatedContext(Pattern->getLocation(),
848 Pattern->getDeclContext(),
852 // Look for a previous declaration of the template in the owning
854 LookupResult R(SemaRef, Pattern->getDeclName(), Pattern->getLocation(),
855 Sema::LookupOrdinaryName, Sema::ForRedeclaration);
856 SemaRef.LookupQualifiedName(R, DC);
858 if (R.isSingleResult()) {
859 PrevClassTemplate = R.getAsSingle<ClassTemplateDecl>();
860 if (PrevClassTemplate)
861 PrevDecl = PrevClassTemplate->getTemplatedDecl();
864 if (!PrevClassTemplate && QualifierLoc) {
865 SemaRef.Diag(Pattern->getLocation(), diag::err_not_tag_in_scope)
866 << D->getTemplatedDecl()->getTagKind() << Pattern->getDeclName() << DC
867 << QualifierLoc.getSourceRange();
871 bool AdoptedPreviousTemplateParams = false;
872 if (PrevClassTemplate) {
873 bool Complain = true;
875 // HACK: libstdc++ 4.2.1 contains an ill-formed friend class
876 // template for struct std::tr1::__detail::_Map_base, where the
877 // template parameters of the friend declaration don't match the
878 // template parameters of the original declaration. In this one
879 // case, we don't complain about the ill-formed friend
881 if (isFriend && Pattern->getIdentifier() &&
882 Pattern->getIdentifier()->isStr("_Map_base") &&
884 cast<NamespaceDecl>(DC)->getIdentifier() &&
885 cast<NamespaceDecl>(DC)->getIdentifier()->isStr("__detail")) {
886 DeclContext *DCParent = DC->getParent();
887 if (DCParent->isNamespace() &&
888 cast<NamespaceDecl>(DCParent)->getIdentifier() &&
889 cast<NamespaceDecl>(DCParent)->getIdentifier()->isStr("tr1")) {
890 if (cast<Decl>(DCParent)->isInStdNamespace())
895 TemplateParameterList *PrevParams
896 = PrevClassTemplate->getTemplateParameters();
898 // Make sure the parameter lists match.
899 if (!SemaRef.TemplateParameterListsAreEqual(InstParams, PrevParams,
901 Sema::TPL_TemplateMatch)) {
905 AdoptedPreviousTemplateParams = true;
906 InstParams = PrevParams;
909 // Do some additional validation, then merge default arguments
910 // from the existing declarations.
911 if (!AdoptedPreviousTemplateParams &&
912 SemaRef.CheckTemplateParameterList(InstParams, PrevParams,
913 Sema::TPC_ClassTemplate))
918 CXXRecordDecl *RecordInst
919 = CXXRecordDecl::Create(SemaRef.Context, Pattern->getTagKind(), DC,
920 Pattern->getLocStart(), Pattern->getLocation(),
921 Pattern->getIdentifier(), PrevDecl,
922 /*DelayTypeCreation=*/true);
925 RecordInst->setQualifierInfo(QualifierLoc);
927 ClassTemplateDecl *Inst
928 = ClassTemplateDecl::Create(SemaRef.Context, DC, D->getLocation(),
929 D->getIdentifier(), InstParams, RecordInst,
931 RecordInst->setDescribedClassTemplate(Inst);
934 if (PrevClassTemplate)
935 Inst->setAccess(PrevClassTemplate->getAccess());
937 Inst->setAccess(D->getAccess());
939 Inst->setObjectOfFriendDecl();
940 // TODO: do we want to track the instantiation progeny of this
941 // friend target decl?
943 Inst->setAccess(D->getAccess());
944 if (!PrevClassTemplate)
945 Inst->setInstantiatedFromMemberTemplate(D);
948 // Trigger creation of the type for the instantiation.
949 SemaRef.Context.getInjectedClassNameType(RecordInst,
950 Inst->getInjectedClassNameSpecialization());
952 // Finish handling of friends.
954 DC->makeDeclVisibleInContext(Inst);
955 Inst->setLexicalDeclContext(Owner);
956 RecordInst->setLexicalDeclContext(Owner);
960 if (D->isOutOfLine()) {
961 Inst->setLexicalDeclContext(D->getLexicalDeclContext());
962 RecordInst->setLexicalDeclContext(D->getLexicalDeclContext());
965 Owner->addDecl(Inst);
967 if (!PrevClassTemplate) {
968 // Queue up any out-of-line partial specializations of this member
969 // class template; the client will force their instantiation once
970 // the enclosing class has been instantiated.
971 SmallVector<ClassTemplatePartialSpecializationDecl *, 4> PartialSpecs;
972 D->getPartialSpecializations(PartialSpecs);
973 for (unsigned I = 0, N = PartialSpecs.size(); I != N; ++I)
974 if (PartialSpecs[I]->getFirstDecl()->isOutOfLine())
975 OutOfLinePartialSpecs.push_back(std::make_pair(Inst, PartialSpecs[I]));
982 TemplateDeclInstantiator::VisitClassTemplatePartialSpecializationDecl(
983 ClassTemplatePartialSpecializationDecl *D) {
984 ClassTemplateDecl *ClassTemplate = D->getSpecializedTemplate();
986 // Lookup the already-instantiated declaration in the instantiation
987 // of the class template and return that.
988 DeclContext::lookup_result Found
989 = Owner->lookup(ClassTemplate->getDeclName());
993 ClassTemplateDecl *InstClassTemplate
994 = dyn_cast<ClassTemplateDecl>(Found.front());
995 if (!InstClassTemplate)
998 if (ClassTemplatePartialSpecializationDecl *Result
999 = InstClassTemplate->findPartialSpecInstantiatedFromMember(D))
1002 return InstantiateClassTemplatePartialSpecialization(InstClassTemplate, D);
1005 Decl *TemplateDeclInstantiator::VisitVarTemplateDecl(VarTemplateDecl *D) {
1006 assert(D->getTemplatedDecl()->isStaticDataMember() &&
1007 "Only static data member templates are allowed.");
1009 // Create a local instantiation scope for this variable template, which
1010 // will contain the instantiations of the template parameters.
1011 LocalInstantiationScope Scope(SemaRef);
1012 TemplateParameterList *TempParams = D->getTemplateParameters();
1013 TemplateParameterList *InstParams = SubstTemplateParams(TempParams);
1017 VarDecl *Pattern = D->getTemplatedDecl();
1018 VarTemplateDecl *PrevVarTemplate = nullptr;
1020 if (Pattern->getPreviousDecl()) {
1021 DeclContext::lookup_result Found = Owner->lookup(Pattern->getDeclName());
1023 PrevVarTemplate = dyn_cast<VarTemplateDecl>(Found.front());
1027 cast_or_null<VarDecl>(VisitVarDecl(Pattern,
1028 /*InstantiatingVarTemplate=*/true));
1030 DeclContext *DC = Owner;
1032 VarTemplateDecl *Inst = VarTemplateDecl::Create(
1033 SemaRef.Context, DC, D->getLocation(), D->getIdentifier(), InstParams,
1035 VarInst->setDescribedVarTemplate(Inst);
1036 Inst->setPreviousDecl(PrevVarTemplate);
1038 Inst->setAccess(D->getAccess());
1039 if (!PrevVarTemplate)
1040 Inst->setInstantiatedFromMemberTemplate(D);
1042 if (D->isOutOfLine()) {
1043 Inst->setLexicalDeclContext(D->getLexicalDeclContext());
1044 VarInst->setLexicalDeclContext(D->getLexicalDeclContext());
1047 Owner->addDecl(Inst);
1049 if (!PrevVarTemplate) {
1050 // Queue up any out-of-line partial specializations of this member
1051 // variable template; the client will force their instantiation once
1052 // the enclosing class has been instantiated.
1053 SmallVector<VarTemplatePartialSpecializationDecl *, 4> PartialSpecs;
1054 D->getPartialSpecializations(PartialSpecs);
1055 for (unsigned I = 0, N = PartialSpecs.size(); I != N; ++I)
1056 if (PartialSpecs[I]->getFirstDecl()->isOutOfLine())
1057 OutOfLineVarPartialSpecs.push_back(
1058 std::make_pair(Inst, PartialSpecs[I]));
1064 Decl *TemplateDeclInstantiator::VisitVarTemplatePartialSpecializationDecl(
1065 VarTemplatePartialSpecializationDecl *D) {
1066 assert(D->isStaticDataMember() &&
1067 "Only static data member templates are allowed.");
1069 VarTemplateDecl *VarTemplate = D->getSpecializedTemplate();
1071 // Lookup the already-instantiated declaration and return that.
1072 DeclContext::lookup_result Found = Owner->lookup(VarTemplate->getDeclName());
1073 assert(!Found.empty() && "Instantiation found nothing?");
1075 VarTemplateDecl *InstVarTemplate = dyn_cast<VarTemplateDecl>(Found.front());
1076 assert(InstVarTemplate && "Instantiation did not find a variable template?");
1078 if (VarTemplatePartialSpecializationDecl *Result =
1079 InstVarTemplate->findPartialSpecInstantiatedFromMember(D))
1082 return InstantiateVarTemplatePartialSpecialization(InstVarTemplate, D);
1086 TemplateDeclInstantiator::VisitFunctionTemplateDecl(FunctionTemplateDecl *D) {
1087 // Create a local instantiation scope for this function template, which
1088 // will contain the instantiations of the template parameters and then get
1089 // merged with the local instantiation scope for the function template
1091 LocalInstantiationScope Scope(SemaRef);
1093 TemplateParameterList *TempParams = D->getTemplateParameters();
1094 TemplateParameterList *InstParams = SubstTemplateParams(TempParams);
1098 FunctionDecl *Instantiated = nullptr;
1099 if (CXXMethodDecl *DMethod = dyn_cast<CXXMethodDecl>(D->getTemplatedDecl()))
1100 Instantiated = cast_or_null<FunctionDecl>(VisitCXXMethodDecl(DMethod,
1103 Instantiated = cast_or_null<FunctionDecl>(VisitFunctionDecl(
1104 D->getTemplatedDecl(),
1110 // Link the instantiated function template declaration to the function
1111 // template from which it was instantiated.
1112 FunctionTemplateDecl *InstTemplate
1113 = Instantiated->getDescribedFunctionTemplate();
1114 InstTemplate->setAccess(D->getAccess());
1115 assert(InstTemplate &&
1116 "VisitFunctionDecl/CXXMethodDecl didn't create a template!");
1118 bool isFriend = (InstTemplate->getFriendObjectKind() != Decl::FOK_None);
1120 // Link the instantiation back to the pattern *unless* this is a
1121 // non-definition friend declaration.
1122 if (!InstTemplate->getInstantiatedFromMemberTemplate() &&
1123 !(isFriend && !D->getTemplatedDecl()->isThisDeclarationADefinition()))
1124 InstTemplate->setInstantiatedFromMemberTemplate(D);
1126 // Make declarations visible in the appropriate context.
1128 Owner->addDecl(InstTemplate);
1129 } else if (InstTemplate->getDeclContext()->isRecord() &&
1130 !D->getPreviousDecl()) {
1131 SemaRef.CheckFriendAccess(InstTemplate);
1134 return InstTemplate;
1137 Decl *TemplateDeclInstantiator::VisitCXXRecordDecl(CXXRecordDecl *D) {
1138 CXXRecordDecl *PrevDecl = nullptr;
1139 if (D->isInjectedClassName())
1140 PrevDecl = cast<CXXRecordDecl>(Owner);
1141 else if (D->getPreviousDecl()) {
1142 NamedDecl *Prev = SemaRef.FindInstantiatedDecl(D->getLocation(),
1143 D->getPreviousDecl(),
1145 if (!Prev) return nullptr;
1146 PrevDecl = cast<CXXRecordDecl>(Prev);
1149 CXXRecordDecl *Record
1150 = CXXRecordDecl::Create(SemaRef.Context, D->getTagKind(), Owner,
1151 D->getLocStart(), D->getLocation(),
1152 D->getIdentifier(), PrevDecl);
1154 // Substitute the nested name specifier, if any.
1155 if (SubstQualifier(D, Record))
1158 Record->setImplicit(D->isImplicit());
1159 // FIXME: Check against AS_none is an ugly hack to work around the issue that
1160 // the tag decls introduced by friend class declarations don't have an access
1161 // specifier. Remove once this area of the code gets sorted out.
1162 if (D->getAccess() != AS_none)
1163 Record->setAccess(D->getAccess());
1164 if (!D->isInjectedClassName())
1165 Record->setInstantiationOfMemberClass(D, TSK_ImplicitInstantiation);
1167 // If the original function was part of a friend declaration,
1168 // inherit its namespace state.
1169 if (D->getFriendObjectKind())
1170 Record->setObjectOfFriendDecl();
1172 // Make sure that anonymous structs and unions are recorded.
1173 if (D->isAnonymousStructOrUnion())
1174 Record->setAnonymousStructOrUnion(true);
1176 if (D->isLocalClass())
1177 SemaRef.CurrentInstantiationScope->InstantiatedLocal(D, Record);
1179 // Forward the mangling number from the template to the instantiated decl.
1180 SemaRef.Context.setManglingNumber(Record,
1181 SemaRef.Context.getManglingNumber(D));
1183 Owner->addDecl(Record);
1185 // DR1484 clarifies that the members of a local class are instantiated as part
1186 // of the instantiation of their enclosing entity.
1187 if (D->isCompleteDefinition() && D->isLocalClass()) {
1188 SemaRef.InstantiateClass(D->getLocation(), Record, D, TemplateArgs,
1189 TSK_ImplicitInstantiation,
1191 SemaRef.InstantiateClassMembers(D->getLocation(), Record, TemplateArgs,
1192 TSK_ImplicitInstantiation);
1197 /// \brief Adjust the given function type for an instantiation of the
1198 /// given declaration, to cope with modifications to the function's type that
1199 /// aren't reflected in the type-source information.
1201 /// \param D The declaration we're instantiating.
1202 /// \param TInfo The already-instantiated type.
1203 static QualType adjustFunctionTypeForInstantiation(ASTContext &Context,
1205 TypeSourceInfo *TInfo) {
1206 const FunctionProtoType *OrigFunc
1207 = D->getType()->castAs<FunctionProtoType>();
1208 const FunctionProtoType *NewFunc
1209 = TInfo->getType()->castAs<FunctionProtoType>();
1210 if (OrigFunc->getExtInfo() == NewFunc->getExtInfo())
1211 return TInfo->getType();
1213 FunctionProtoType::ExtProtoInfo NewEPI = NewFunc->getExtProtoInfo();
1214 NewEPI.ExtInfo = OrigFunc->getExtInfo();
1215 return Context.getFunctionType(NewFunc->getReturnType(),
1216 NewFunc->getParamTypes(), NewEPI);
1219 /// Normal class members are of more specific types and therefore
1220 /// don't make it here. This function serves two purposes:
1221 /// 1) instantiating function templates
1222 /// 2) substituting friend declarations
1223 Decl *TemplateDeclInstantiator::VisitFunctionDecl(FunctionDecl *D,
1224 TemplateParameterList *TemplateParams) {
1225 // Check whether there is already a function template specialization for
1226 // this declaration.
1227 FunctionTemplateDecl *FunctionTemplate = D->getDescribedFunctionTemplate();
1228 if (FunctionTemplate && !TemplateParams) {
1229 ArrayRef<TemplateArgument> Innermost = TemplateArgs.getInnermost();
1231 void *InsertPos = nullptr;
1232 FunctionDecl *SpecFunc
1233 = FunctionTemplate->findSpecialization(Innermost, InsertPos);
1235 // If we already have a function template specialization, return it.
1241 if (FunctionTemplate)
1242 isFriend = (FunctionTemplate->getFriendObjectKind() != Decl::FOK_None);
1244 isFriend = (D->getFriendObjectKind() != Decl::FOK_None);
1246 bool MergeWithParentScope = (TemplateParams != nullptr) ||
1247 Owner->isFunctionOrMethod() ||
1248 !(isa<Decl>(Owner) &&
1249 cast<Decl>(Owner)->isDefinedOutsideFunctionOrMethod());
1250 LocalInstantiationScope Scope(SemaRef, MergeWithParentScope);
1252 SmallVector<ParmVarDecl *, 4> Params;
1253 TypeSourceInfo *TInfo = SubstFunctionType(D, Params);
1256 QualType T = adjustFunctionTypeForInstantiation(SemaRef.Context, D, TInfo);
1258 NestedNameSpecifierLoc QualifierLoc = D->getQualifierLoc();
1260 QualifierLoc = SemaRef.SubstNestedNameSpecifierLoc(QualifierLoc,
1266 // If we're instantiating a local function declaration, put the result
1267 // in the enclosing namespace; otherwise we need to find the instantiated
1270 if (D->isLocalExternDecl()) {
1272 SemaRef.adjustContextForLocalExternDecl(DC);
1273 } else if (isFriend && QualifierLoc) {
1275 SS.Adopt(QualifierLoc);
1276 DC = SemaRef.computeDeclContext(SS);
1277 if (!DC) return nullptr;
1279 DC = SemaRef.FindInstantiatedContext(D->getLocation(), D->getDeclContext(),
1283 FunctionDecl *Function =
1284 FunctionDecl::Create(SemaRef.Context, DC, D->getInnerLocStart(),
1285 D->getNameInfo(), T, TInfo,
1286 D->getCanonicalDecl()->getStorageClass(),
1287 D->isInlineSpecified(), D->hasWrittenPrototype(),
1289 Function->setRangeEnd(D->getSourceRange().getEnd());
1292 Function->setImplicitlyInline();
1295 Function->setQualifierInfo(QualifierLoc);
1297 if (D->isLocalExternDecl())
1298 Function->setLocalExternDecl();
1300 DeclContext *LexicalDC = Owner;
1301 if (!isFriend && D->isOutOfLine() && !D->isLocalExternDecl()) {
1302 assert(D->getDeclContext()->isFileContext());
1303 LexicalDC = D->getDeclContext();
1306 Function->setLexicalDeclContext(LexicalDC);
1308 // Attach the parameters
1309 for (unsigned P = 0; P < Params.size(); ++P)
1311 Params[P]->setOwningFunction(Function);
1312 Function->setParams(Params);
1314 SourceLocation InstantiateAtPOI;
1315 if (TemplateParams) {
1316 // Our resulting instantiation is actually a function template, since we
1317 // are substituting only the outer template parameters. For example, given
1319 // template<typename T>
1321 // template<typename U> friend void f(T, U);
1326 // We are instantiating the friend function template "f" within X<int>,
1327 // which means substituting int for T, but leaving "f" as a friend function
1329 // Build the function template itself.
1330 FunctionTemplate = FunctionTemplateDecl::Create(SemaRef.Context, DC,
1331 Function->getLocation(),
1332 Function->getDeclName(),
1333 TemplateParams, Function);
1334 Function->setDescribedFunctionTemplate(FunctionTemplate);
1336 FunctionTemplate->setLexicalDeclContext(LexicalDC);
1338 if (isFriend && D->isThisDeclarationADefinition()) {
1339 // TODO: should we remember this connection regardless of whether
1340 // the friend declaration provided a body?
1341 FunctionTemplate->setInstantiatedFromMemberTemplate(
1342 D->getDescribedFunctionTemplate());
1344 } else if (FunctionTemplate) {
1345 // Record this function template specialization.
1346 ArrayRef<TemplateArgument> Innermost = TemplateArgs.getInnermost();
1347 Function->setFunctionTemplateSpecialization(FunctionTemplate,
1348 TemplateArgumentList::CreateCopy(SemaRef.Context,
1351 /*InsertPos=*/nullptr);
1352 } else if (isFriend) {
1353 // Note, we need this connection even if the friend doesn't have a body.
1354 // Its body may exist but not have been attached yet due to deferred
1356 // FIXME: It might be cleaner to set this when attaching the body to the
1357 // friend function declaration, however that would require finding all the
1358 // instantiations and modifying them.
1359 Function->setInstantiationOfMemberFunction(D, TSK_ImplicitInstantiation);
1362 if (InitFunctionInstantiation(Function, D))
1363 Function->setInvalidDecl();
1365 bool isExplicitSpecialization = false;
1367 LookupResult Previous(
1368 SemaRef, Function->getDeclName(), SourceLocation(),
1369 D->isLocalExternDecl() ? Sema::LookupRedeclarationWithLinkage
1370 : Sema::LookupOrdinaryName,
1371 Sema::ForRedeclaration);
1373 if (DependentFunctionTemplateSpecializationInfo *Info
1374 = D->getDependentSpecializationInfo()) {
1375 assert(isFriend && "non-friend has dependent specialization info?");
1377 // This needs to be set now for future sanity.
1378 Function->setObjectOfFriendDecl();
1380 // Instantiate the explicit template arguments.
1381 TemplateArgumentListInfo ExplicitArgs(Info->getLAngleLoc(),
1382 Info->getRAngleLoc());
1383 if (SemaRef.Subst(Info->getTemplateArgs(), Info->getNumTemplateArgs(),
1384 ExplicitArgs, TemplateArgs))
1387 // Map the candidate templates to their instantiations.
1388 for (unsigned I = 0, E = Info->getNumTemplates(); I != E; ++I) {
1389 Decl *Temp = SemaRef.FindInstantiatedDecl(D->getLocation(),
1390 Info->getTemplate(I),
1392 if (!Temp) return nullptr;
1394 Previous.addDecl(cast<FunctionTemplateDecl>(Temp));
1397 if (SemaRef.CheckFunctionTemplateSpecialization(Function,
1400 Function->setInvalidDecl();
1402 isExplicitSpecialization = true;
1404 } else if (TemplateParams || !FunctionTemplate) {
1405 // Look only into the namespace where the friend would be declared to
1406 // find a previous declaration. This is the innermost enclosing namespace,
1407 // as described in ActOnFriendFunctionDecl.
1408 SemaRef.LookupQualifiedName(Previous, DC);
1410 // In C++, the previous declaration we find might be a tag type
1411 // (class or enum). In this case, the new declaration will hide the
1412 // tag type. Note that this does does not apply if we're declaring a
1413 // typedef (C++ [dcl.typedef]p4).
1414 if (Previous.isSingleTagDecl())
1418 SemaRef.CheckFunctionDeclaration(/*Scope*/ nullptr, Function, Previous,
1419 isExplicitSpecialization);
1421 NamedDecl *PrincipalDecl = (TemplateParams
1422 ? cast<NamedDecl>(FunctionTemplate)
1425 // If the original function was part of a friend declaration,
1426 // inherit its namespace state and add it to the owner.
1428 PrincipalDecl->setObjectOfFriendDecl();
1429 DC->makeDeclVisibleInContext(PrincipalDecl);
1431 bool QueuedInstantiation = false;
1433 // C++11 [temp.friend]p4 (DR329):
1434 // When a function is defined in a friend function declaration in a class
1435 // template, the function is instantiated when the function is odr-used.
1436 // The same restrictions on multiple declarations and definitions that
1437 // apply to non-template function declarations and definitions also apply
1438 // to these implicit definitions.
1439 if (D->isThisDeclarationADefinition()) {
1440 // Check for a function body.
1441 const FunctionDecl *Definition = nullptr;
1442 if (Function->isDefined(Definition) &&
1443 Definition->getTemplateSpecializationKind() == TSK_Undeclared) {
1444 SemaRef.Diag(Function->getLocation(), diag::err_redefinition)
1445 << Function->getDeclName();
1446 SemaRef.Diag(Definition->getLocation(), diag::note_previous_definition);
1448 // Check for redefinitions due to other instantiations of this or
1449 // a similar friend function.
1450 else for (auto R : Function->redecls()) {
1454 // If some prior declaration of this function has been used, we need
1455 // to instantiate its definition.
1456 if (!QueuedInstantiation && R->isUsed(false)) {
1457 if (MemberSpecializationInfo *MSInfo =
1458 Function->getMemberSpecializationInfo()) {
1459 if (MSInfo->getPointOfInstantiation().isInvalid()) {
1460 SourceLocation Loc = R->getLocation(); // FIXME
1461 MSInfo->setPointOfInstantiation(Loc);
1462 SemaRef.PendingLocalImplicitInstantiations.push_back(
1463 std::make_pair(Function, Loc));
1464 QueuedInstantiation = true;
1469 // If some prior declaration of this function was a friend with an
1470 // uninstantiated definition, reject it.
1471 if (R->getFriendObjectKind()) {
1472 if (const FunctionDecl *RPattern =
1473 R->getTemplateInstantiationPattern()) {
1474 if (RPattern->isDefined(RPattern)) {
1475 SemaRef.Diag(Function->getLocation(), diag::err_redefinition)
1476 << Function->getDeclName();
1477 SemaRef.Diag(R->getLocation(), diag::note_previous_definition);
1486 if (Function->isLocalExternDecl() && !Function->getPreviousDecl())
1487 DC->makeDeclVisibleInContext(PrincipalDecl);
1489 if (Function->isOverloadedOperator() && !DC->isRecord() &&
1490 PrincipalDecl->isInIdentifierNamespace(Decl::IDNS_Ordinary))
1491 PrincipalDecl->setNonMemberOperator();
1493 assert(!D->isDefaulted() && "only methods should be defaulted");
1498 TemplateDeclInstantiator::VisitCXXMethodDecl(CXXMethodDecl *D,
1499 TemplateParameterList *TemplateParams,
1500 bool IsClassScopeSpecialization) {
1501 FunctionTemplateDecl *FunctionTemplate = D->getDescribedFunctionTemplate();
1502 if (FunctionTemplate && !TemplateParams) {
1503 // We are creating a function template specialization from a function
1504 // template. Check whether there is already a function template
1505 // specialization for this particular set of template arguments.
1506 ArrayRef<TemplateArgument> Innermost = TemplateArgs.getInnermost();
1508 void *InsertPos = nullptr;
1509 FunctionDecl *SpecFunc
1510 = FunctionTemplate->findSpecialization(Innermost, InsertPos);
1512 // If we already have a function template specialization, return it.
1518 if (FunctionTemplate)
1519 isFriend = (FunctionTemplate->getFriendObjectKind() != Decl::FOK_None);
1521 isFriend = (D->getFriendObjectKind() != Decl::FOK_None);
1523 bool MergeWithParentScope = (TemplateParams != nullptr) ||
1524 !(isa<Decl>(Owner) &&
1525 cast<Decl>(Owner)->isDefinedOutsideFunctionOrMethod());
1526 LocalInstantiationScope Scope(SemaRef, MergeWithParentScope);
1528 // Instantiate enclosing template arguments for friends.
1529 SmallVector<TemplateParameterList *, 4> TempParamLists;
1530 unsigned NumTempParamLists = 0;
1531 if (isFriend && (NumTempParamLists = D->getNumTemplateParameterLists())) {
1532 TempParamLists.set_size(NumTempParamLists);
1533 for (unsigned I = 0; I != NumTempParamLists; ++I) {
1534 TemplateParameterList *TempParams = D->getTemplateParameterList(I);
1535 TemplateParameterList *InstParams = SubstTemplateParams(TempParams);
1538 TempParamLists[I] = InstParams;
1542 SmallVector<ParmVarDecl *, 4> Params;
1543 TypeSourceInfo *TInfo = SubstFunctionType(D, Params);
1546 QualType T = adjustFunctionTypeForInstantiation(SemaRef.Context, D, TInfo);
1548 NestedNameSpecifierLoc QualifierLoc = D->getQualifierLoc();
1550 QualifierLoc = SemaRef.SubstNestedNameSpecifierLoc(QualifierLoc,
1556 DeclContext *DC = Owner;
1560 SS.Adopt(QualifierLoc);
1561 DC = SemaRef.computeDeclContext(SS);
1563 if (DC && SemaRef.RequireCompleteDeclContext(SS, DC))
1566 DC = SemaRef.FindInstantiatedContext(D->getLocation(),
1567 D->getDeclContext(),
1570 if (!DC) return nullptr;
1573 // Build the instantiated method declaration.
1574 CXXRecordDecl *Record = cast<CXXRecordDecl>(DC);
1575 CXXMethodDecl *Method = nullptr;
1577 SourceLocation StartLoc = D->getInnerLocStart();
1578 DeclarationNameInfo NameInfo
1579 = SemaRef.SubstDeclarationNameInfo(D->getNameInfo(), TemplateArgs);
1580 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(D)) {
1581 Method = CXXConstructorDecl::Create(SemaRef.Context, Record,
1582 StartLoc, NameInfo, T, TInfo,
1583 Constructor->isExplicit(),
1584 Constructor->isInlineSpecified(),
1585 false, Constructor->isConstexpr());
1587 // Claim that the instantiation of a constructor or constructor template
1588 // inherits the same constructor that the template does.
1589 if (CXXConstructorDecl *Inh = const_cast<CXXConstructorDecl *>(
1590 Constructor->getInheritedConstructor())) {
1591 // If we're instantiating a specialization of a function template, our
1592 // "inherited constructor" will actually itself be a function template.
1593 // Instantiate a declaration of it, too.
1594 if (FunctionTemplate) {
1595 assert(!TemplateParams && Inh->getDescribedFunctionTemplate() &&
1596 !Inh->getParent()->isDependentContext() &&
1597 "inheriting constructor template in dependent context?");
1598 Sema::InstantiatingTemplate Inst(SemaRef, Constructor->getLocation(),
1600 if (Inst.isInvalid())
1602 Sema::ContextRAII SavedContext(SemaRef, Inh->getDeclContext());
1603 LocalInstantiationScope LocalScope(SemaRef);
1605 // Use the same template arguments that we deduced for the inheriting
1606 // constructor. There's no way they could be deduced differently.
1607 MultiLevelTemplateArgumentList InheritedArgs;
1608 InheritedArgs.addOuterTemplateArguments(TemplateArgs.getInnermost());
1609 Inh = cast_or_null<CXXConstructorDecl>(
1610 SemaRef.SubstDecl(Inh, Inh->getDeclContext(), InheritedArgs));
1614 cast<CXXConstructorDecl>(Method)->setInheritedConstructor(Inh);
1616 } else if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(D)) {
1617 Method = CXXDestructorDecl::Create(SemaRef.Context, Record,
1618 StartLoc, NameInfo, T, TInfo,
1619 Destructor->isInlineSpecified(),
1621 } else if (CXXConversionDecl *Conversion = dyn_cast<CXXConversionDecl>(D)) {
1622 Method = CXXConversionDecl::Create(SemaRef.Context, Record,
1623 StartLoc, NameInfo, T, TInfo,
1624 Conversion->isInlineSpecified(),
1625 Conversion->isExplicit(),
1626 Conversion->isConstexpr(),
1627 Conversion->getLocEnd());
1629 StorageClass SC = D->isStatic() ? SC_Static : SC_None;
1630 Method = CXXMethodDecl::Create(SemaRef.Context, Record,
1631 StartLoc, NameInfo, T, TInfo,
1632 SC, D->isInlineSpecified(),
1633 D->isConstexpr(), D->getLocEnd());
1637 Method->setImplicitlyInline();
1640 Method->setQualifierInfo(QualifierLoc);
1642 if (TemplateParams) {
1643 // Our resulting instantiation is actually a function template, since we
1644 // are substituting only the outer template parameters. For example, given
1646 // template<typename T>
1648 // template<typename U> void f(T, U);
1653 // We are instantiating the member template "f" within X<int>, which means
1654 // substituting int for T, but leaving "f" as a member function template.
1655 // Build the function template itself.
1656 FunctionTemplate = FunctionTemplateDecl::Create(SemaRef.Context, Record,
1657 Method->getLocation(),
1658 Method->getDeclName(),
1659 TemplateParams, Method);
1661 FunctionTemplate->setLexicalDeclContext(Owner);
1662 FunctionTemplate->setObjectOfFriendDecl();
1663 } else if (D->isOutOfLine())
1664 FunctionTemplate->setLexicalDeclContext(D->getLexicalDeclContext());
1665 Method->setDescribedFunctionTemplate(FunctionTemplate);
1666 } else if (FunctionTemplate) {
1667 // Record this function template specialization.
1668 ArrayRef<TemplateArgument> Innermost = TemplateArgs.getInnermost();
1669 Method->setFunctionTemplateSpecialization(FunctionTemplate,
1670 TemplateArgumentList::CreateCopy(SemaRef.Context,
1673 /*InsertPos=*/nullptr);
1674 } else if (!isFriend) {
1675 // Record that this is an instantiation of a member function.
1676 Method->setInstantiationOfMemberFunction(D, TSK_ImplicitInstantiation);
1679 // If we are instantiating a member function defined
1680 // out-of-line, the instantiation will have the same lexical
1681 // context (which will be a namespace scope) as the template.
1683 if (NumTempParamLists)
1684 Method->setTemplateParameterListsInfo(SemaRef.Context,
1686 TempParamLists.data());
1688 Method->setLexicalDeclContext(Owner);
1689 Method->setObjectOfFriendDecl();
1690 } else if (D->isOutOfLine())
1691 Method->setLexicalDeclContext(D->getLexicalDeclContext());
1693 // Attach the parameters
1694 for (unsigned P = 0; P < Params.size(); ++P)
1695 Params[P]->setOwningFunction(Method);
1696 Method->setParams(Params);
1698 if (InitMethodInstantiation(Method, D))
1699 Method->setInvalidDecl();
1701 LookupResult Previous(SemaRef, NameInfo, Sema::LookupOrdinaryName,
1702 Sema::ForRedeclaration);
1704 if (!FunctionTemplate || TemplateParams || isFriend) {
1705 SemaRef.LookupQualifiedName(Previous, Record);
1707 // In C++, the previous declaration we find might be a tag type
1708 // (class or enum). In this case, the new declaration will hide the
1709 // tag type. Note that this does does not apply if we're declaring a
1710 // typedef (C++ [dcl.typedef]p4).
1711 if (Previous.isSingleTagDecl())
1715 if (!IsClassScopeSpecialization)
1716 SemaRef.CheckFunctionDeclaration(nullptr, Method, Previous, false);
1719 SemaRef.CheckPureMethod(Method, SourceRange());
1721 // Propagate access. For a non-friend declaration, the access is
1722 // whatever we're propagating from. For a friend, it should be the
1723 // previous declaration we just found.
1724 if (isFriend && Method->getPreviousDecl())
1725 Method->setAccess(Method->getPreviousDecl()->getAccess());
1727 Method->setAccess(D->getAccess());
1728 if (FunctionTemplate)
1729 FunctionTemplate->setAccess(Method->getAccess());
1731 SemaRef.CheckOverrideControl(Method);
1733 // If a function is defined as defaulted or deleted, mark it as such now.
1734 if (D->isExplicitlyDefaulted())
1735 SemaRef.SetDeclDefaulted(Method, Method->getLocation());
1736 if (D->isDeletedAsWritten())
1737 SemaRef.SetDeclDeleted(Method, Method->getLocation());
1739 // If there's a function template, let our caller handle it.
1740 if (FunctionTemplate) {
1743 // Don't hide a (potentially) valid declaration with an invalid one.
1744 } else if (Method->isInvalidDecl() && !Previous.empty()) {
1747 // Otherwise, check access to friends and make them visible.
1748 } else if (isFriend) {
1749 // We only need to re-check access for methods which we didn't
1750 // manage to match during parsing.
1751 if (!D->getPreviousDecl())
1752 SemaRef.CheckFriendAccess(Method);
1754 Record->makeDeclVisibleInContext(Method);
1756 // Otherwise, add the declaration. We don't need to do this for
1757 // class-scope specializations because we'll have matched them with
1758 // the appropriate template.
1759 } else if (!IsClassScopeSpecialization) {
1760 Owner->addDecl(Method);
1766 Decl *TemplateDeclInstantiator::VisitCXXConstructorDecl(CXXConstructorDecl *D) {
1767 return VisitCXXMethodDecl(D);
1770 Decl *TemplateDeclInstantiator::VisitCXXDestructorDecl(CXXDestructorDecl *D) {
1771 return VisitCXXMethodDecl(D);
1774 Decl *TemplateDeclInstantiator::VisitCXXConversionDecl(CXXConversionDecl *D) {
1775 return VisitCXXMethodDecl(D);
1778 Decl *TemplateDeclInstantiator::VisitParmVarDecl(ParmVarDecl *D) {
1779 return SemaRef.SubstParmVarDecl(D, TemplateArgs, /*indexAdjustment*/ 0, None,
1780 /*ExpectParameterPack=*/ false);
1783 Decl *TemplateDeclInstantiator::VisitTemplateTypeParmDecl(
1784 TemplateTypeParmDecl *D) {
1785 // TODO: don't always clone when decls are refcounted.
1786 assert(D->getTypeForDecl()->isTemplateTypeParmType());
1788 TemplateTypeParmDecl *Inst =
1789 TemplateTypeParmDecl::Create(SemaRef.Context, Owner,
1790 D->getLocStart(), D->getLocation(),
1791 D->getDepth() - TemplateArgs.getNumLevels(),
1792 D->getIndex(), D->getIdentifier(),
1793 D->wasDeclaredWithTypename(),
1794 D->isParameterPack());
1795 Inst->setAccess(AS_public);
1797 if (D->hasDefaultArgument()) {
1798 TypeSourceInfo *InstantiatedDefaultArg =
1799 SemaRef.SubstType(D->getDefaultArgumentInfo(), TemplateArgs,
1800 D->getDefaultArgumentLoc(), D->getDeclName());
1801 if (InstantiatedDefaultArg)
1802 Inst->setDefaultArgument(InstantiatedDefaultArg, false);
1805 // Introduce this template parameter's instantiation into the instantiation
1807 SemaRef.CurrentInstantiationScope->InstantiatedLocal(D, Inst);
1812 Decl *TemplateDeclInstantiator::VisitNonTypeTemplateParmDecl(
1813 NonTypeTemplateParmDecl *D) {
1814 // Substitute into the type of the non-type template parameter.
1815 TypeLoc TL = D->getTypeSourceInfo()->getTypeLoc();
1816 SmallVector<TypeSourceInfo *, 4> ExpandedParameterPackTypesAsWritten;
1817 SmallVector<QualType, 4> ExpandedParameterPackTypes;
1818 bool IsExpandedParameterPack = false;
1821 bool Invalid = false;
1823 if (D->isExpandedParameterPack()) {
1824 // The non-type template parameter pack is an already-expanded pack
1825 // expansion of types. Substitute into each of the expanded types.
1826 ExpandedParameterPackTypes.reserve(D->getNumExpansionTypes());
1827 ExpandedParameterPackTypesAsWritten.reserve(D->getNumExpansionTypes());
1828 for (unsigned I = 0, N = D->getNumExpansionTypes(); I != N; ++I) {
1829 TypeSourceInfo *NewDI =SemaRef.SubstType(D->getExpansionTypeSourceInfo(I),
1836 ExpandedParameterPackTypesAsWritten.push_back(NewDI);
1837 QualType NewT =SemaRef.CheckNonTypeTemplateParameterType(NewDI->getType(),
1841 ExpandedParameterPackTypes.push_back(NewT);
1844 IsExpandedParameterPack = true;
1845 DI = D->getTypeSourceInfo();
1847 } else if (D->isPackExpansion()) {
1848 // The non-type template parameter pack's type is a pack expansion of types.
1849 // Determine whether we need to expand this parameter pack into separate
1851 PackExpansionTypeLoc Expansion = TL.castAs<PackExpansionTypeLoc>();
1852 TypeLoc Pattern = Expansion.getPatternLoc();
1853 SmallVector<UnexpandedParameterPack, 2> Unexpanded;
1854 SemaRef.collectUnexpandedParameterPacks(Pattern, Unexpanded);
1856 // Determine whether the set of unexpanded parameter packs can and should
1859 bool RetainExpansion = false;
1860 Optional<unsigned> OrigNumExpansions
1861 = Expansion.getTypePtr()->getNumExpansions();
1862 Optional<unsigned> NumExpansions = OrigNumExpansions;
1863 if (SemaRef.CheckParameterPacksForExpansion(Expansion.getEllipsisLoc(),
1864 Pattern.getSourceRange(),
1867 Expand, RetainExpansion,
1872 for (unsigned I = 0; I != *NumExpansions; ++I) {
1873 Sema::ArgumentPackSubstitutionIndexRAII SubstIndex(SemaRef, I);
1874 TypeSourceInfo *NewDI = SemaRef.SubstType(Pattern, TemplateArgs,
1880 ExpandedParameterPackTypesAsWritten.push_back(NewDI);
1881 QualType NewT = SemaRef.CheckNonTypeTemplateParameterType(
1886 ExpandedParameterPackTypes.push_back(NewT);
1889 // Note that we have an expanded parameter pack. The "type" of this
1890 // expanded parameter pack is the original expansion type, but callers
1891 // will end up using the expanded parameter pack types for type-checking.
1892 IsExpandedParameterPack = true;
1893 DI = D->getTypeSourceInfo();
1896 // We cannot fully expand the pack expansion now, so substitute into the
1897 // pattern and create a new pack expansion type.
1898 Sema::ArgumentPackSubstitutionIndexRAII SubstIndex(SemaRef, -1);
1899 TypeSourceInfo *NewPattern = SemaRef.SubstType(Pattern, TemplateArgs,
1905 DI = SemaRef.CheckPackExpansion(NewPattern, Expansion.getEllipsisLoc(),
1913 // Simple case: substitution into a parameter that is not a parameter pack.
1914 DI = SemaRef.SubstType(D->getTypeSourceInfo(), TemplateArgs,
1915 D->getLocation(), D->getDeclName());
1919 // Check that this type is acceptable for a non-type template parameter.
1920 T = SemaRef.CheckNonTypeTemplateParameterType(DI->getType(),
1923 T = SemaRef.Context.IntTy;
1928 NonTypeTemplateParmDecl *Param;
1929 if (IsExpandedParameterPack)
1930 Param = NonTypeTemplateParmDecl::Create(SemaRef.Context, Owner,
1931 D->getInnerLocStart(),
1933 D->getDepth() - TemplateArgs.getNumLevels(),
1935 D->getIdentifier(), T,
1937 ExpandedParameterPackTypes.data(),
1938 ExpandedParameterPackTypes.size(),
1939 ExpandedParameterPackTypesAsWritten.data());
1941 Param = NonTypeTemplateParmDecl::Create(SemaRef.Context, Owner,
1942 D->getInnerLocStart(),
1944 D->getDepth() - TemplateArgs.getNumLevels(),
1946 D->getIdentifier(), T,
1947 D->isParameterPack(), DI);
1949 Param->setAccess(AS_public);
1951 Param->setInvalidDecl();
1953 if (D->hasDefaultArgument()) {
1954 ExprResult Value = SemaRef.SubstExpr(D->getDefaultArgument(), TemplateArgs);
1955 if (!Value.isInvalid())
1956 Param->setDefaultArgument(Value.get(), false);
1959 // Introduce this template parameter's instantiation into the instantiation
1961 SemaRef.CurrentInstantiationScope->InstantiatedLocal(D, Param);
1965 static void collectUnexpandedParameterPacks(
1967 TemplateParameterList *Params,
1968 SmallVectorImpl<UnexpandedParameterPack> &Unexpanded) {
1969 for (TemplateParameterList::const_iterator I = Params->begin(),
1970 E = Params->end(); I != E; ++I) {
1971 if ((*I)->isTemplateParameterPack())
1973 if (NonTypeTemplateParmDecl *NTTP = dyn_cast<NonTypeTemplateParmDecl>(*I))
1974 S.collectUnexpandedParameterPacks(NTTP->getTypeSourceInfo()->getTypeLoc(),
1976 if (TemplateTemplateParmDecl *TTP = dyn_cast<TemplateTemplateParmDecl>(*I))
1977 collectUnexpandedParameterPacks(S, TTP->getTemplateParameters(),
1983 TemplateDeclInstantiator::VisitTemplateTemplateParmDecl(
1984 TemplateTemplateParmDecl *D) {
1985 // Instantiate the template parameter list of the template template parameter.
1986 TemplateParameterList *TempParams = D->getTemplateParameters();
1987 TemplateParameterList *InstParams;
1988 SmallVector<TemplateParameterList*, 8> ExpandedParams;
1990 bool IsExpandedParameterPack = false;
1992 if (D->isExpandedParameterPack()) {
1993 // The template template parameter pack is an already-expanded pack
1994 // expansion of template parameters. Substitute into each of the expanded
1996 ExpandedParams.reserve(D->getNumExpansionTemplateParameters());
1997 for (unsigned I = 0, N = D->getNumExpansionTemplateParameters();
1999 LocalInstantiationScope Scope(SemaRef);
2000 TemplateParameterList *Expansion =
2001 SubstTemplateParams(D->getExpansionTemplateParameters(I));
2004 ExpandedParams.push_back(Expansion);
2007 IsExpandedParameterPack = true;
2008 InstParams = TempParams;
2009 } else if (D->isPackExpansion()) {
2010 // The template template parameter pack expands to a pack of template
2011 // template parameters. Determine whether we need to expand this parameter
2012 // pack into separate parameters.
2013 SmallVector<UnexpandedParameterPack, 2> Unexpanded;
2014 collectUnexpandedParameterPacks(SemaRef, D->getTemplateParameters(),
2017 // Determine whether the set of unexpanded parameter packs can and should
2020 bool RetainExpansion = false;
2021 Optional<unsigned> NumExpansions;
2022 if (SemaRef.CheckParameterPacksForExpansion(D->getLocation(),
2023 TempParams->getSourceRange(),
2026 Expand, RetainExpansion,
2031 for (unsigned I = 0; I != *NumExpansions; ++I) {
2032 Sema::ArgumentPackSubstitutionIndexRAII SubstIndex(SemaRef, I);
2033 LocalInstantiationScope Scope(SemaRef);
2034 TemplateParameterList *Expansion = SubstTemplateParams(TempParams);
2037 ExpandedParams.push_back(Expansion);
2040 // Note that we have an expanded parameter pack. The "type" of this
2041 // expanded parameter pack is the original expansion type, but callers
2042 // will end up using the expanded parameter pack types for type-checking.
2043 IsExpandedParameterPack = true;
2044 InstParams = TempParams;
2046 // We cannot fully expand the pack expansion now, so just substitute
2047 // into the pattern.
2048 Sema::ArgumentPackSubstitutionIndexRAII SubstIndex(SemaRef, -1);
2050 LocalInstantiationScope Scope(SemaRef);
2051 InstParams = SubstTemplateParams(TempParams);
2056 // Perform the actual substitution of template parameters within a new,
2057 // local instantiation scope.
2058 LocalInstantiationScope Scope(SemaRef);
2059 InstParams = SubstTemplateParams(TempParams);
2064 // Build the template template parameter.
2065 TemplateTemplateParmDecl *Param;
2066 if (IsExpandedParameterPack)
2067 Param = TemplateTemplateParmDecl::Create(SemaRef.Context, Owner,
2069 D->getDepth() - TemplateArgs.getNumLevels(),
2071 D->getIdentifier(), InstParams,
2074 Param = TemplateTemplateParmDecl::Create(SemaRef.Context, Owner,
2076 D->getDepth() - TemplateArgs.getNumLevels(),
2078 D->isParameterPack(),
2079 D->getIdentifier(), InstParams);
2080 if (D->hasDefaultArgument()) {
2081 NestedNameSpecifierLoc QualifierLoc =
2082 D->getDefaultArgument().getTemplateQualifierLoc();
2084 SemaRef.SubstNestedNameSpecifierLoc(QualifierLoc, TemplateArgs);
2085 TemplateName TName = SemaRef.SubstTemplateName(
2086 QualifierLoc, D->getDefaultArgument().getArgument().getAsTemplate(),
2087 D->getDefaultArgument().getTemplateNameLoc(), TemplateArgs);
2088 if (!TName.isNull())
2089 Param->setDefaultArgument(
2090 TemplateArgumentLoc(TemplateArgument(TName),
2091 D->getDefaultArgument().getTemplateQualifierLoc(),
2092 D->getDefaultArgument().getTemplateNameLoc()),
2095 Param->setAccess(AS_public);
2097 // Introduce this template parameter's instantiation into the instantiation
2099 SemaRef.CurrentInstantiationScope->InstantiatedLocal(D, Param);
2104 Decl *TemplateDeclInstantiator::VisitUsingDirectiveDecl(UsingDirectiveDecl *D) {
2105 // Using directives are never dependent (and never contain any types or
2106 // expressions), so they require no explicit instantiation work.
2108 UsingDirectiveDecl *Inst
2109 = UsingDirectiveDecl::Create(SemaRef.Context, Owner, D->getLocation(),
2110 D->getNamespaceKeyLocation(),
2111 D->getQualifierLoc(),
2112 D->getIdentLocation(),
2113 D->getNominatedNamespace(),
2114 D->getCommonAncestor());
2116 // Add the using directive to its declaration context
2117 // only if this is not a function or method.
2118 if (!Owner->isFunctionOrMethod())
2119 Owner->addDecl(Inst);
2124 Decl *TemplateDeclInstantiator::VisitUsingDecl(UsingDecl *D) {
2126 // The nested name specifier may be dependent, for example
2127 // template <typename T> struct t {
2128 // struct s1 { T f1(); };
2129 // struct s2 : s1 { using s1::f1; };
2131 // template struct t<int>;
2132 // Here, in using s1::f1, s1 refers to t<T>::s1;
2133 // we need to substitute for t<int>::s1.
2134 NestedNameSpecifierLoc QualifierLoc
2135 = SemaRef.SubstNestedNameSpecifierLoc(D->getQualifierLoc(),
2140 // The name info is non-dependent, so no transformation
2142 DeclarationNameInfo NameInfo = D->getNameInfo();
2144 // We only need to do redeclaration lookups if we're in a class
2145 // scope (in fact, it's not really even possible in non-class
2147 bool CheckRedeclaration = Owner->isRecord();
2149 LookupResult Prev(SemaRef, NameInfo, Sema::LookupUsingDeclName,
2150 Sema::ForRedeclaration);
2152 UsingDecl *NewUD = UsingDecl::Create(SemaRef.Context, Owner,
2159 SS.Adopt(QualifierLoc);
2160 if (CheckRedeclaration) {
2161 Prev.setHideTags(false);
2162 SemaRef.LookupQualifiedName(Prev, Owner);
2164 // Check for invalid redeclarations.
2165 if (SemaRef.CheckUsingDeclRedeclaration(D->getUsingLoc(),
2166 D->hasTypename(), SS,
2167 D->getLocation(), Prev))
2168 NewUD->setInvalidDecl();
2172 if (!NewUD->isInvalidDecl() &&
2173 SemaRef.CheckUsingDeclQualifier(D->getUsingLoc(), SS, NameInfo,
2175 NewUD->setInvalidDecl();
2177 SemaRef.Context.setInstantiatedFromUsingDecl(NewUD, D);
2178 NewUD->setAccess(D->getAccess());
2179 Owner->addDecl(NewUD);
2181 // Don't process the shadow decls for an invalid decl.
2182 if (NewUD->isInvalidDecl())
2185 if (NameInfo.getName().getNameKind() == DeclarationName::CXXConstructorName) {
2186 SemaRef.CheckInheritingConstructorUsingDecl(NewUD);
2190 bool isFunctionScope = Owner->isFunctionOrMethod();
2192 // Process the shadow decls.
2193 for (auto *Shadow : D->shadows()) {
2194 NamedDecl *InstTarget =
2195 cast_or_null<NamedDecl>(SemaRef.FindInstantiatedDecl(
2196 Shadow->getLocation(), Shadow->getTargetDecl(), TemplateArgs));
2200 UsingShadowDecl *PrevDecl = nullptr;
2201 if (CheckRedeclaration) {
2202 if (SemaRef.CheckUsingShadowDecl(NewUD, InstTarget, Prev, PrevDecl))
2204 } else if (UsingShadowDecl *OldPrev = Shadow->getPreviousDecl()) {
2205 PrevDecl = cast_or_null<UsingShadowDecl>(SemaRef.FindInstantiatedDecl(
2206 Shadow->getLocation(), OldPrev, TemplateArgs));
2209 UsingShadowDecl *InstShadow =
2210 SemaRef.BuildUsingShadowDecl(/*Scope*/nullptr, NewUD, InstTarget,
2212 SemaRef.Context.setInstantiatedFromUsingShadowDecl(InstShadow, Shadow);
2214 if (isFunctionScope)
2215 SemaRef.CurrentInstantiationScope->InstantiatedLocal(Shadow, InstShadow);
2221 Decl *TemplateDeclInstantiator::VisitUsingShadowDecl(UsingShadowDecl *D) {
2222 // Ignore these; we handle them in bulk when processing the UsingDecl.
2226 Decl * TemplateDeclInstantiator
2227 ::VisitUnresolvedUsingTypenameDecl(UnresolvedUsingTypenameDecl *D) {
2228 NestedNameSpecifierLoc QualifierLoc
2229 = SemaRef.SubstNestedNameSpecifierLoc(D->getQualifierLoc(),
2235 SS.Adopt(QualifierLoc);
2237 // Since NameInfo refers to a typename, it cannot be a C++ special name.
2238 // Hence, no transformation is required for it.
2239 DeclarationNameInfo NameInfo(D->getDeclName(), D->getLocation());
2241 SemaRef.BuildUsingDeclaration(/*Scope*/ nullptr, D->getAccess(),
2242 D->getUsingLoc(), SS, NameInfo, nullptr,
2243 /*instantiation*/ true,
2244 /*typename*/ true, D->getTypenameLoc());
2246 SemaRef.Context.setInstantiatedFromUsingDecl(cast<UsingDecl>(UD), D);
2251 Decl * TemplateDeclInstantiator
2252 ::VisitUnresolvedUsingValueDecl(UnresolvedUsingValueDecl *D) {
2253 NestedNameSpecifierLoc QualifierLoc
2254 = SemaRef.SubstNestedNameSpecifierLoc(D->getQualifierLoc(), TemplateArgs);
2259 SS.Adopt(QualifierLoc);
2261 DeclarationNameInfo NameInfo
2262 = SemaRef.SubstDeclarationNameInfo(D->getNameInfo(), TemplateArgs);
2265 SemaRef.BuildUsingDeclaration(/*Scope*/ nullptr, D->getAccess(),
2266 D->getUsingLoc(), SS, NameInfo, nullptr,
2267 /*instantiation*/ true,
2268 /*typename*/ false, SourceLocation());
2270 SemaRef.Context.setInstantiatedFromUsingDecl(cast<UsingDecl>(UD), D);
2276 Decl *TemplateDeclInstantiator::VisitClassScopeFunctionSpecializationDecl(
2277 ClassScopeFunctionSpecializationDecl *Decl) {
2278 CXXMethodDecl *OldFD = Decl->getSpecialization();
2279 CXXMethodDecl *NewFD = cast<CXXMethodDecl>(VisitCXXMethodDecl(OldFD,
2282 LookupResult Previous(SemaRef, NewFD->getNameInfo(), Sema::LookupOrdinaryName,
2283 Sema::ForRedeclaration);
2285 TemplateArgumentListInfo TemplateArgs;
2286 TemplateArgumentListInfo *TemplateArgsPtr = nullptr;
2287 if (Decl->hasExplicitTemplateArgs()) {
2288 TemplateArgs = Decl->templateArgs();
2289 TemplateArgsPtr = &TemplateArgs;
2292 SemaRef.LookupQualifiedName(Previous, SemaRef.CurContext);
2293 if (SemaRef.CheckFunctionTemplateSpecialization(NewFD, TemplateArgsPtr,
2295 NewFD->setInvalidDecl();
2299 // Associate the specialization with the pattern.
2300 FunctionDecl *Specialization = cast<FunctionDecl>(Previous.getFoundDecl());
2301 assert(Specialization && "Class scope Specialization is null");
2302 SemaRef.Context.setClassScopeSpecializationPattern(Specialization, OldFD);
2307 Decl *TemplateDeclInstantiator::VisitOMPThreadPrivateDecl(
2308 OMPThreadPrivateDecl *D) {
2309 SmallVector<Expr *, 5> Vars;
2310 for (auto *I : D->varlists()) {
2311 Expr *Var = SemaRef.SubstExpr(I, TemplateArgs).get();
2312 assert(isa<DeclRefExpr>(Var) && "threadprivate arg is not a DeclRefExpr");
2313 Vars.push_back(Var);
2316 OMPThreadPrivateDecl *TD =
2317 SemaRef.CheckOMPThreadPrivateDecl(D->getLocation(), Vars);
2319 TD->setAccess(AS_public);
2325 Decl *TemplateDeclInstantiator::VisitFunctionDecl(FunctionDecl *D) {
2326 return VisitFunctionDecl(D, nullptr);
2329 Decl *TemplateDeclInstantiator::VisitCXXMethodDecl(CXXMethodDecl *D) {
2330 return VisitCXXMethodDecl(D, nullptr);
2333 Decl *TemplateDeclInstantiator::VisitRecordDecl(RecordDecl *D) {
2334 llvm_unreachable("There are only CXXRecordDecls in C++");
2338 TemplateDeclInstantiator::VisitClassTemplateSpecializationDecl(
2339 ClassTemplateSpecializationDecl *D) {
2340 // As a MS extension, we permit class-scope explicit specialization
2341 // of member class templates.
2342 ClassTemplateDecl *ClassTemplate = D->getSpecializedTemplate();
2343 assert(ClassTemplate->getDeclContext()->isRecord() &&
2344 D->getTemplateSpecializationKind() == TSK_ExplicitSpecialization &&
2345 "can only instantiate an explicit specialization "
2346 "for a member class template");
2348 // Lookup the already-instantiated declaration in the instantiation
2349 // of the class template. FIXME: Diagnose or assert if this fails?
2350 DeclContext::lookup_result Found
2351 = Owner->lookup(ClassTemplate->getDeclName());
2354 ClassTemplateDecl *InstClassTemplate
2355 = dyn_cast<ClassTemplateDecl>(Found.front());
2356 if (!InstClassTemplate)
2359 // Substitute into the template arguments of the class template explicit
2361 TemplateSpecializationTypeLoc Loc = D->getTypeAsWritten()->getTypeLoc().
2362 castAs<TemplateSpecializationTypeLoc>();
2363 TemplateArgumentListInfo InstTemplateArgs(Loc.getLAngleLoc(),
2364 Loc.getRAngleLoc());
2365 SmallVector<TemplateArgumentLoc, 4> ArgLocs;
2366 for (unsigned I = 0; I != Loc.getNumArgs(); ++I)
2367 ArgLocs.push_back(Loc.getArgLoc(I));
2368 if (SemaRef.Subst(ArgLocs.data(), ArgLocs.size(),
2369 InstTemplateArgs, TemplateArgs))
2372 // Check that the template argument list is well-formed for this
2374 SmallVector<TemplateArgument, 4> Converted;
2375 if (SemaRef.CheckTemplateArgumentList(InstClassTemplate,
2382 // Figure out where to insert this class template explicit specialization
2383 // in the member template's set of class template explicit specializations.
2384 void *InsertPos = nullptr;
2385 ClassTemplateSpecializationDecl *PrevDecl =
2386 InstClassTemplate->findSpecialization(Converted, InsertPos);
2388 // Check whether we've already seen a conflicting instantiation of this
2389 // declaration (for instance, if there was a prior implicit instantiation).
2392 SemaRef.CheckSpecializationInstantiationRedecl(D->getLocation(),
2393 D->getSpecializationKind(),
2395 PrevDecl->getSpecializationKind(),
2396 PrevDecl->getPointOfInstantiation(),
2400 // If PrevDecl was a definition and D is also a definition, diagnose.
2401 // This happens in cases like:
2403 // template<typename T, typename U>
2405 // template<typename X> struct Inner;
2406 // template<> struct Inner<T> {};
2407 // template<> struct Inner<U> {};
2410 // Outer<int, int> outer; // error: the explicit specializations of Inner
2411 // // have the same signature.
2412 if (PrevDecl && PrevDecl->getDefinition() &&
2413 D->isThisDeclarationADefinition()) {
2414 SemaRef.Diag(D->getLocation(), diag::err_redefinition) << PrevDecl;
2415 SemaRef.Diag(PrevDecl->getDefinition()->getLocation(),
2416 diag::note_previous_definition);
2420 // Create the class template partial specialization declaration.
2421 ClassTemplateSpecializationDecl *InstD
2422 = ClassTemplateSpecializationDecl::Create(SemaRef.Context,
2432 // Add this partial specialization to the set of class template partial
2435 InstClassTemplate->AddSpecialization(InstD, InsertPos);
2437 // Substitute the nested name specifier, if any.
2438 if (SubstQualifier(D, InstD))
2441 // Build the canonical type that describes the converted template
2442 // arguments of the class template explicit specialization.
2443 QualType CanonType = SemaRef.Context.getTemplateSpecializationType(
2444 TemplateName(InstClassTemplate), Converted.data(), Converted.size(),
2445 SemaRef.Context.getRecordType(InstD));
2447 // Build the fully-sugared type for this class template
2448 // specialization as the user wrote in the specialization
2449 // itself. This means that we'll pretty-print the type retrieved
2450 // from the specialization's declaration the way that the user
2451 // actually wrote the specialization, rather than formatting the
2452 // name based on the "canonical" representation used to store the
2453 // template arguments in the specialization.
2454 TypeSourceInfo *WrittenTy = SemaRef.Context.getTemplateSpecializationTypeInfo(
2455 TemplateName(InstClassTemplate), D->getLocation(), InstTemplateArgs,
2458 InstD->setAccess(D->getAccess());
2459 InstD->setInstantiationOfMemberClass(D, TSK_ImplicitInstantiation);
2460 InstD->setSpecializationKind(D->getSpecializationKind());
2461 InstD->setTypeAsWritten(WrittenTy);
2462 InstD->setExternLoc(D->getExternLoc());
2463 InstD->setTemplateKeywordLoc(D->getTemplateKeywordLoc());
2465 Owner->addDecl(InstD);
2467 // Instantiate the members of the class-scope explicit specialization eagerly.
2468 // We don't have support for lazy instantiation of an explicit specialization
2469 // yet, and MSVC eagerly instantiates in this case.
2470 if (D->isThisDeclarationADefinition() &&
2471 SemaRef.InstantiateClass(D->getLocation(), InstD, D, TemplateArgs,
2472 TSK_ImplicitInstantiation,
2479 Decl *TemplateDeclInstantiator::VisitVarTemplateSpecializationDecl(
2480 VarTemplateSpecializationDecl *D) {
2482 TemplateArgumentListInfo VarTemplateArgsInfo;
2483 VarTemplateDecl *VarTemplate = D->getSpecializedTemplate();
2484 assert(VarTemplate &&
2485 "A template specialization without specialized template?");
2487 // Substitute the current template arguments.
2488 const TemplateArgumentListInfo &TemplateArgsInfo = D->getTemplateArgsInfo();
2489 VarTemplateArgsInfo.setLAngleLoc(TemplateArgsInfo.getLAngleLoc());
2490 VarTemplateArgsInfo.setRAngleLoc(TemplateArgsInfo.getRAngleLoc());
2492 if (SemaRef.Subst(TemplateArgsInfo.getArgumentArray(),
2493 TemplateArgsInfo.size(), VarTemplateArgsInfo, TemplateArgs))
2496 // Check that the template argument list is well-formed for this template.
2497 SmallVector<TemplateArgument, 4> Converted;
2498 if (SemaRef.CheckTemplateArgumentList(
2499 VarTemplate, VarTemplate->getLocStart(),
2500 const_cast<TemplateArgumentListInfo &>(VarTemplateArgsInfo), false,
2504 // Find the variable template specialization declaration that
2505 // corresponds to these arguments.
2506 void *InsertPos = nullptr;
2507 if (VarTemplateSpecializationDecl *VarSpec = VarTemplate->findSpecialization(
2508 Converted, InsertPos))
2509 // If we already have a variable template specialization, return it.
2512 return VisitVarTemplateSpecializationDecl(VarTemplate, D, InsertPos,
2513 VarTemplateArgsInfo, Converted);
2516 Decl *TemplateDeclInstantiator::VisitVarTemplateSpecializationDecl(
2517 VarTemplateDecl *VarTemplate, VarDecl *D, void *InsertPos,
2518 const TemplateArgumentListInfo &TemplateArgsInfo,
2519 ArrayRef<TemplateArgument> Converted) {
2521 // If this is the variable for an anonymous struct or union,
2522 // instantiate the anonymous struct/union type first.
2523 if (const RecordType *RecordTy = D->getType()->getAs<RecordType>())
2524 if (RecordTy->getDecl()->isAnonymousStructOrUnion())
2525 if (!VisitCXXRecordDecl(cast<CXXRecordDecl>(RecordTy->getDecl())))
2528 // Do substitution on the type of the declaration
2529 TypeSourceInfo *DI =
2530 SemaRef.SubstType(D->getTypeSourceInfo(), TemplateArgs,
2531 D->getTypeSpecStartLoc(), D->getDeclName());
2535 if (DI->getType()->isFunctionType()) {
2536 SemaRef.Diag(D->getLocation(), diag::err_variable_instantiates_to_function)
2537 << D->isStaticDataMember() << DI->getType();
2541 // Build the instantiated declaration
2542 VarTemplateSpecializationDecl *Var = VarTemplateSpecializationDecl::Create(
2543 SemaRef.Context, Owner, D->getInnerLocStart(), D->getLocation(),
2544 VarTemplate, DI->getType(), DI, D->getStorageClass(), Converted.data(),
2546 Var->setTemplateArgsInfo(TemplateArgsInfo);
2548 VarTemplate->AddSpecialization(Var, InsertPos);
2550 // Substitute the nested name specifier, if any.
2551 if (SubstQualifier(D, Var))
2554 SemaRef.BuildVariableInstantiation(Var, D, TemplateArgs, LateAttrs,
2555 Owner, StartingScope);
2560 Decl *TemplateDeclInstantiator::VisitObjCAtDefsFieldDecl(ObjCAtDefsFieldDecl *D) {
2561 llvm_unreachable("@defs is not supported in Objective-C++");
2564 Decl *TemplateDeclInstantiator::VisitFriendTemplateDecl(FriendTemplateDecl *D) {
2565 // FIXME: We need to be able to instantiate FriendTemplateDecls.
2566 unsigned DiagID = SemaRef.getDiagnostics().getCustomDiagID(
2567 DiagnosticsEngine::Error,
2568 "cannot instantiate %0 yet");
2569 SemaRef.Diag(D->getLocation(), DiagID)
2570 << D->getDeclKindName();
2575 Decl *TemplateDeclInstantiator::VisitDecl(Decl *D) {
2576 llvm_unreachable("Unexpected decl");
2579 Decl *Sema::SubstDecl(Decl *D, DeclContext *Owner,
2580 const MultiLevelTemplateArgumentList &TemplateArgs) {
2581 TemplateDeclInstantiator Instantiator(*this, Owner, TemplateArgs);
2582 if (D->isInvalidDecl())
2585 return Instantiator.Visit(D);
2588 /// \brief Instantiates a nested template parameter list in the current
2589 /// instantiation context.
2591 /// \param L The parameter list to instantiate
2593 /// \returns NULL if there was an error
2594 TemplateParameterList *
2595 TemplateDeclInstantiator::SubstTemplateParams(TemplateParameterList *L) {
2596 // Get errors for all the parameters before bailing out.
2597 bool Invalid = false;
2599 unsigned N = L->size();
2600 typedef SmallVector<NamedDecl *, 8> ParamVector;
2603 for (TemplateParameterList::iterator PI = L->begin(), PE = L->end();
2605 NamedDecl *D = cast_or_null<NamedDecl>(Visit(*PI));
2606 Params.push_back(D);
2607 Invalid = Invalid || !D || D->isInvalidDecl();
2610 // Clean up if we had an error.
2614 TemplateParameterList *InstL
2615 = TemplateParameterList::Create(SemaRef.Context, L->getTemplateLoc(),
2616 L->getLAngleLoc(), &Params.front(), N,
2621 /// \brief Instantiate the declaration of a class template partial
2624 /// \param ClassTemplate the (instantiated) class template that is partially
2625 // specialized by the instantiation of \p PartialSpec.
2627 /// \param PartialSpec the (uninstantiated) class template partial
2628 /// specialization that we are instantiating.
2630 /// \returns The instantiated partial specialization, if successful; otherwise,
2631 /// NULL to indicate an error.
2632 ClassTemplatePartialSpecializationDecl *
2633 TemplateDeclInstantiator::InstantiateClassTemplatePartialSpecialization(
2634 ClassTemplateDecl *ClassTemplate,
2635 ClassTemplatePartialSpecializationDecl *PartialSpec) {
2636 // Create a local instantiation scope for this class template partial
2637 // specialization, which will contain the instantiations of the template
2639 LocalInstantiationScope Scope(SemaRef);
2641 // Substitute into the template parameters of the class template partial
2643 TemplateParameterList *TempParams = PartialSpec->getTemplateParameters();
2644 TemplateParameterList *InstParams = SubstTemplateParams(TempParams);
2648 // Substitute into the template arguments of the class template partial
2650 const ASTTemplateArgumentListInfo *TemplArgInfo
2651 = PartialSpec->getTemplateArgsAsWritten();
2652 TemplateArgumentListInfo InstTemplateArgs(TemplArgInfo->LAngleLoc,
2653 TemplArgInfo->RAngleLoc);
2654 if (SemaRef.Subst(TemplArgInfo->getTemplateArgs(),
2655 TemplArgInfo->NumTemplateArgs,
2656 InstTemplateArgs, TemplateArgs))
2659 // Check that the template argument list is well-formed for this
2661 SmallVector<TemplateArgument, 4> Converted;
2662 if (SemaRef.CheckTemplateArgumentList(ClassTemplate,
2663 PartialSpec->getLocation(),
2669 // Figure out where to insert this class template partial specialization
2670 // in the member template's set of class template partial specializations.
2671 void *InsertPos = nullptr;
2672 ClassTemplateSpecializationDecl *PrevDecl
2673 = ClassTemplate->findPartialSpecialization(Converted, InsertPos);
2675 // Build the canonical type that describes the converted template
2676 // arguments of the class template partial specialization.
2678 = SemaRef.Context.getTemplateSpecializationType(TemplateName(ClassTemplate),
2682 // Build the fully-sugared type for this class template
2683 // specialization as the user wrote in the specialization
2684 // itself. This means that we'll pretty-print the type retrieved
2685 // from the specialization's declaration the way that the user
2686 // actually wrote the specialization, rather than formatting the
2687 // name based on the "canonical" representation used to store the
2688 // template arguments in the specialization.
2689 TypeSourceInfo *WrittenTy
2690 = SemaRef.Context.getTemplateSpecializationTypeInfo(
2691 TemplateName(ClassTemplate),
2692 PartialSpec->getLocation(),
2697 // We've already seen a partial specialization with the same template
2698 // parameters and template arguments. This can happen, for example, when
2699 // substituting the outer template arguments ends up causing two
2700 // class template partial specializations of a member class template
2701 // to have identical forms, e.g.,
2703 // template<typename T, typename U>
2705 // template<typename X, typename Y> struct Inner;
2706 // template<typename Y> struct Inner<T, Y>;
2707 // template<typename Y> struct Inner<U, Y>;
2710 // Outer<int, int> outer; // error: the partial specializations of Inner
2711 // // have the same signature.
2712 SemaRef.Diag(PartialSpec->getLocation(), diag::err_partial_spec_redeclared)
2713 << WrittenTy->getType();
2714 SemaRef.Diag(PrevDecl->getLocation(), diag::note_prev_partial_spec_here)
2715 << SemaRef.Context.getTypeDeclType(PrevDecl);
2720 // Create the class template partial specialization declaration.
2721 ClassTemplatePartialSpecializationDecl *InstPartialSpec
2722 = ClassTemplatePartialSpecializationDecl::Create(SemaRef.Context,
2723 PartialSpec->getTagKind(),
2725 PartialSpec->getLocStart(),
2726 PartialSpec->getLocation(),
2734 // Substitute the nested name specifier, if any.
2735 if (SubstQualifier(PartialSpec, InstPartialSpec))
2738 InstPartialSpec->setInstantiatedFromMember(PartialSpec);
2739 InstPartialSpec->setTypeAsWritten(WrittenTy);
2741 // Add this partial specialization to the set of class template partial
2743 ClassTemplate->AddPartialSpecialization(InstPartialSpec,
2744 /*InsertPos=*/nullptr);
2745 return InstPartialSpec;
2748 /// \brief Instantiate the declaration of a variable template partial
2751 /// \param VarTemplate the (instantiated) variable template that is partially
2752 /// specialized by the instantiation of \p PartialSpec.
2754 /// \param PartialSpec the (uninstantiated) variable template partial
2755 /// specialization that we are instantiating.
2757 /// \returns The instantiated partial specialization, if successful; otherwise,
2758 /// NULL to indicate an error.
2759 VarTemplatePartialSpecializationDecl *
2760 TemplateDeclInstantiator::InstantiateVarTemplatePartialSpecialization(
2761 VarTemplateDecl *VarTemplate,
2762 VarTemplatePartialSpecializationDecl *PartialSpec) {
2763 // Create a local instantiation scope for this variable template partial
2764 // specialization, which will contain the instantiations of the template
2766 LocalInstantiationScope Scope(SemaRef);
2768 // Substitute into the template parameters of the variable template partial
2770 TemplateParameterList *TempParams = PartialSpec->getTemplateParameters();
2771 TemplateParameterList *InstParams = SubstTemplateParams(TempParams);
2775 // Substitute into the template arguments of the variable template partial
2777 const ASTTemplateArgumentListInfo *TemplArgInfo
2778 = PartialSpec->getTemplateArgsAsWritten();
2779 TemplateArgumentListInfo InstTemplateArgs(TemplArgInfo->LAngleLoc,
2780 TemplArgInfo->RAngleLoc);
2781 if (SemaRef.Subst(TemplArgInfo->getTemplateArgs(),
2782 TemplArgInfo->NumTemplateArgs,
2783 InstTemplateArgs, TemplateArgs))
2786 // Check that the template argument list is well-formed for this
2788 SmallVector<TemplateArgument, 4> Converted;
2789 if (SemaRef.CheckTemplateArgumentList(VarTemplate, PartialSpec->getLocation(),
2790 InstTemplateArgs, false, Converted))
2793 // Figure out where to insert this variable template partial specialization
2794 // in the member template's set of variable template partial specializations.
2795 void *InsertPos = nullptr;
2796 VarTemplateSpecializationDecl *PrevDecl =
2797 VarTemplate->findPartialSpecialization(Converted, InsertPos);
2799 // Build the canonical type that describes the converted template
2800 // arguments of the variable template partial specialization.
2801 QualType CanonType = SemaRef.Context.getTemplateSpecializationType(
2802 TemplateName(VarTemplate), Converted.data(), Converted.size());
2804 // Build the fully-sugared type for this variable template
2805 // specialization as the user wrote in the specialization
2806 // itself. This means that we'll pretty-print the type retrieved
2807 // from the specialization's declaration the way that the user
2808 // actually wrote the specialization, rather than formatting the
2809 // name based on the "canonical" representation used to store the
2810 // template arguments in the specialization.
2811 TypeSourceInfo *WrittenTy = SemaRef.Context.getTemplateSpecializationTypeInfo(
2812 TemplateName(VarTemplate), PartialSpec->getLocation(), InstTemplateArgs,
2816 // We've already seen a partial specialization with the same template
2817 // parameters and template arguments. This can happen, for example, when
2818 // substituting the outer template arguments ends up causing two
2819 // variable template partial specializations of a member variable template
2820 // to have identical forms, e.g.,
2822 // template<typename T, typename U>
2824 // template<typename X, typename Y> pair<X,Y> p;
2825 // template<typename Y> pair<T, Y> p;
2826 // template<typename Y> pair<U, Y> p;
2829 // Outer<int, int> outer; // error: the partial specializations of Inner
2830 // // have the same signature.
2831 SemaRef.Diag(PartialSpec->getLocation(),
2832 diag::err_var_partial_spec_redeclared)
2833 << WrittenTy->getType();
2834 SemaRef.Diag(PrevDecl->getLocation(),
2835 diag::note_var_prev_partial_spec_here);
2839 // Do substitution on the type of the declaration
2840 TypeSourceInfo *DI = SemaRef.SubstType(
2841 PartialSpec->getTypeSourceInfo(), TemplateArgs,
2842 PartialSpec->getTypeSpecStartLoc(), PartialSpec->getDeclName());
2846 if (DI->getType()->isFunctionType()) {
2847 SemaRef.Diag(PartialSpec->getLocation(),
2848 diag::err_variable_instantiates_to_function)
2849 << PartialSpec->isStaticDataMember() << DI->getType();
2853 // Create the variable template partial specialization declaration.
2854 VarTemplatePartialSpecializationDecl *InstPartialSpec =
2855 VarTemplatePartialSpecializationDecl::Create(
2856 SemaRef.Context, Owner, PartialSpec->getInnerLocStart(),
2857 PartialSpec->getLocation(), InstParams, VarTemplate, DI->getType(),
2858 DI, PartialSpec->getStorageClass(), Converted.data(),
2859 Converted.size(), InstTemplateArgs);
2861 // Substitute the nested name specifier, if any.
2862 if (SubstQualifier(PartialSpec, InstPartialSpec))
2865 InstPartialSpec->setInstantiatedFromMember(PartialSpec);
2866 InstPartialSpec->setTypeAsWritten(WrittenTy);
2868 // Add this partial specialization to the set of variable template partial
2869 // specializations. The instantiation of the initializer is not necessary.
2870 VarTemplate->AddPartialSpecialization(InstPartialSpec, /*InsertPos=*/nullptr);
2872 SemaRef.BuildVariableInstantiation(InstPartialSpec, PartialSpec, TemplateArgs,
2873 LateAttrs, Owner, StartingScope);
2875 return InstPartialSpec;
2879 TemplateDeclInstantiator::SubstFunctionType(FunctionDecl *D,
2880 SmallVectorImpl<ParmVarDecl *> &Params) {
2881 TypeSourceInfo *OldTInfo = D->getTypeSourceInfo();
2882 assert(OldTInfo && "substituting function without type source info");
2883 assert(Params.empty() && "parameter vector is non-empty at start");
2885 CXXRecordDecl *ThisContext = nullptr;
2886 unsigned ThisTypeQuals = 0;
2887 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(D)) {
2888 ThisContext = cast<CXXRecordDecl>(Owner);
2889 ThisTypeQuals = Method->getTypeQualifiers();
2892 TypeSourceInfo *NewTInfo
2893 = SemaRef.SubstFunctionDeclType(OldTInfo, TemplateArgs,
2894 D->getTypeSpecStartLoc(),
2896 ThisContext, ThisTypeQuals);
2900 TypeLoc OldTL = OldTInfo->getTypeLoc().IgnoreParens();
2901 if (FunctionProtoTypeLoc OldProtoLoc = OldTL.getAs<FunctionProtoTypeLoc>()) {
2902 if (NewTInfo != OldTInfo) {
2903 // Get parameters from the new type info.
2904 TypeLoc NewTL = NewTInfo->getTypeLoc().IgnoreParens();
2905 FunctionProtoTypeLoc NewProtoLoc = NewTL.castAs<FunctionProtoTypeLoc>();
2906 unsigned NewIdx = 0;
2907 for (unsigned OldIdx = 0, NumOldParams = OldProtoLoc.getNumParams();
2908 OldIdx != NumOldParams; ++OldIdx) {
2909 ParmVarDecl *OldParam = OldProtoLoc.getParam(OldIdx);
2910 LocalInstantiationScope *Scope = SemaRef.CurrentInstantiationScope;
2912 Optional<unsigned> NumArgumentsInExpansion;
2913 if (OldParam->isParameterPack())
2914 NumArgumentsInExpansion =
2915 SemaRef.getNumArgumentsInExpansion(OldParam->getType(),
2917 if (!NumArgumentsInExpansion) {
2918 // Simple case: normal parameter, or a parameter pack that's
2919 // instantiated to a (still-dependent) parameter pack.
2920 ParmVarDecl *NewParam = NewProtoLoc.getParam(NewIdx++);
2921 Params.push_back(NewParam);
2922 Scope->InstantiatedLocal(OldParam, NewParam);
2924 // Parameter pack expansion: make the instantiation an argument pack.
2925 Scope->MakeInstantiatedLocalArgPack(OldParam);
2926 for (unsigned I = 0; I != *NumArgumentsInExpansion; ++I) {
2927 ParmVarDecl *NewParam = NewProtoLoc.getParam(NewIdx++);
2928 Params.push_back(NewParam);
2929 Scope->InstantiatedLocalPackArg(OldParam, NewParam);
2934 // The function type itself was not dependent and therefore no
2935 // substitution occurred. However, we still need to instantiate
2936 // the function parameters themselves.
2937 const FunctionProtoType *OldProto =
2938 cast<FunctionProtoType>(OldProtoLoc.getType());
2939 for (unsigned i = 0, i_end = OldProtoLoc.getNumParams(); i != i_end;
2941 ParmVarDecl *OldParam = OldProtoLoc.getParam(i);
2943 Params.push_back(SemaRef.BuildParmVarDeclForTypedef(
2944 D, D->getLocation(), OldProto->getParamType(i)));
2949 cast_or_null<ParmVarDecl>(VisitParmVarDecl(OldParam));
2952 Params.push_back(Parm);
2956 // If the type of this function, after ignoring parentheses, is not
2957 // *directly* a function type, then we're instantiating a function that
2958 // was declared via a typedef or with attributes, e.g.,
2960 // typedef int functype(int, int);
2962 // int __cdecl meth(int, int);
2964 // In this case, we'll just go instantiate the ParmVarDecls that we
2965 // synthesized in the method declaration.
2966 SmallVector<QualType, 4> ParamTypes;
2967 if (SemaRef.SubstParmTypes(D->getLocation(), D->param_begin(),
2968 D->getNumParams(), TemplateArgs, ParamTypes,
2976 /// Introduce the instantiated function parameters into the local
2977 /// instantiation scope, and set the parameter names to those used
2978 /// in the template.
2979 static void addInstantiatedParametersToScope(Sema &S, FunctionDecl *Function,
2980 const FunctionDecl *PatternDecl,
2981 LocalInstantiationScope &Scope,
2982 const MultiLevelTemplateArgumentList &TemplateArgs) {
2983 unsigned FParamIdx = 0;
2984 for (unsigned I = 0, N = PatternDecl->getNumParams(); I != N; ++I) {
2985 const ParmVarDecl *PatternParam = PatternDecl->getParamDecl(I);
2986 if (!PatternParam->isParameterPack()) {
2987 // Simple case: not a parameter pack.
2988 assert(FParamIdx < Function->getNumParams());
2989 ParmVarDecl *FunctionParam = Function->getParamDecl(FParamIdx);
2990 // If the parameter's type is not dependent, update it to match the type
2991 // in the pattern. They can differ in top-level cv-qualifiers, and we want
2992 // the pattern's type here. If the type is dependent, they can't differ,
2993 // per core issue 1668.
2994 // FIXME: Updating the type to work around this is at best fragile.
2995 if (!PatternDecl->getType()->isDependentType())
2996 FunctionParam->setType(PatternParam->getType());
2998 FunctionParam->setDeclName(PatternParam->getDeclName());
2999 Scope.InstantiatedLocal(PatternParam, FunctionParam);
3004 // Expand the parameter pack.
3005 Scope.MakeInstantiatedLocalArgPack(PatternParam);
3006 Optional<unsigned> NumArgumentsInExpansion
3007 = S.getNumArgumentsInExpansion(PatternParam->getType(), TemplateArgs);
3008 assert(NumArgumentsInExpansion &&
3009 "should only be called when all template arguments are known");
3010 for (unsigned Arg = 0; Arg < *NumArgumentsInExpansion; ++Arg) {
3011 ParmVarDecl *FunctionParam = Function->getParamDecl(FParamIdx);
3012 if (!PatternDecl->getType()->isDependentType())
3013 FunctionParam->setType(PatternParam->getType());
3015 FunctionParam->setDeclName(PatternParam->getDeclName());
3016 Scope.InstantiatedLocalPackArg(PatternParam, FunctionParam);
3022 static void InstantiateExceptionSpec(Sema &SemaRef, FunctionDecl *New,
3023 const FunctionProtoType *Proto,
3024 const MultiLevelTemplateArgumentList &TemplateArgs) {
3025 assert(Proto->getExceptionSpecType() != EST_Uninstantiated);
3027 // C++11 [expr.prim.general]p3:
3028 // If a declaration declares a member function or member function
3029 // template of a class X, the expression this is a prvalue of type
3030 // "pointer to cv-qualifier-seq X" between the optional cv-qualifer-seq
3031 // and the end of the function-definition, member-declarator, or
3033 CXXRecordDecl *ThisContext = nullptr;
3034 unsigned ThisTypeQuals = 0;
3035 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(New)) {
3036 ThisContext = Method->getParent();
3037 ThisTypeQuals = Method->getTypeQualifiers();
3039 Sema::CXXThisScopeRAII ThisScope(SemaRef, ThisContext, ThisTypeQuals,
3040 SemaRef.getLangOpts().CPlusPlus11);
3042 // The function has an exception specification or a "noreturn"
3043 // attribute. Substitute into each of the exception types.
3044 SmallVector<QualType, 4> Exceptions;
3045 for (unsigned I = 0, N = Proto->getNumExceptions(); I != N; ++I) {
3046 // FIXME: Poor location information!
3047 if (const PackExpansionType *PackExpansion
3048 = Proto->getExceptionType(I)->getAs<PackExpansionType>()) {
3049 // We have a pack expansion. Instantiate it.
3050 SmallVector<UnexpandedParameterPack, 2> Unexpanded;
3051 SemaRef.collectUnexpandedParameterPacks(PackExpansion->getPattern(),
3053 assert(!Unexpanded.empty() &&
3054 "Pack expansion without parameter packs?");
3056 bool Expand = false;
3057 bool RetainExpansion = false;
3058 Optional<unsigned> NumExpansions = PackExpansion->getNumExpansions();
3059 if (SemaRef.CheckParameterPacksForExpansion(New->getLocation(),
3069 // We can't expand this pack expansion into separate arguments yet;
3070 // just substitute into the pattern and create a new pack expansion
3072 Sema::ArgumentPackSubstitutionIndexRAII SubstIndex(SemaRef, -1);
3073 QualType T = SemaRef.SubstType(PackExpansion->getPattern(),
3075 New->getLocation(), New->getDeclName());
3079 T = SemaRef.Context.getPackExpansionType(T, NumExpansions);
3080 Exceptions.push_back(T);
3084 // Substitute into the pack expansion pattern for each template
3085 bool Invalid = false;
3086 for (unsigned ArgIdx = 0; ArgIdx != *NumExpansions; ++ArgIdx) {
3087 Sema::ArgumentPackSubstitutionIndexRAII SubstIndex(SemaRef, ArgIdx);
3089 QualType T = SemaRef.SubstType(PackExpansion->getPattern(),
3091 New->getLocation(), New->getDeclName());
3097 Exceptions.push_back(T);
3107 = SemaRef.SubstType(Proto->getExceptionType(I), TemplateArgs,
3108 New->getLocation(), New->getDeclName());
3110 SemaRef.CheckSpecifiedExceptionType(T, New->getLocation()))
3113 Exceptions.push_back(T);
3115 Expr *NoexceptExpr = nullptr;
3116 if (Expr *OldNoexceptExpr = Proto->getNoexceptExpr()) {
3117 EnterExpressionEvaluationContext Unevaluated(SemaRef,
3118 Sema::ConstantEvaluated);
3119 ExprResult E = SemaRef.SubstExpr(OldNoexceptExpr, TemplateArgs);
3121 E = SemaRef.CheckBooleanCondition(E.get(), E.get()->getLocStart());
3124 NoexceptExpr = E.get();
3125 if (!NoexceptExpr->isTypeDependent() &&
3126 !NoexceptExpr->isValueDependent())
3128 = SemaRef.VerifyIntegerConstantExpression(NoexceptExpr,
3129 nullptr, diag::err_noexcept_needs_constant_expression,
3130 /*AllowFold*/ false).get();
3134 FunctionProtoType::ExtProtoInfo EPI;
3135 EPI.ExceptionSpecType = Proto->getExceptionSpecType();
3136 EPI.NumExceptions = Exceptions.size();
3137 EPI.Exceptions = Exceptions.data();
3138 EPI.NoexceptExpr = NoexceptExpr;
3140 SemaRef.UpdateExceptionSpec(New, EPI);
3143 void Sema::InstantiateExceptionSpec(SourceLocation PointOfInstantiation,
3144 FunctionDecl *Decl) {
3145 const FunctionProtoType *Proto = Decl->getType()->castAs<FunctionProtoType>();
3146 if (Proto->getExceptionSpecType() != EST_Uninstantiated)
3149 InstantiatingTemplate Inst(*this, PointOfInstantiation, Decl,
3150 InstantiatingTemplate::ExceptionSpecification());
3151 if (Inst.isInvalid()) {
3152 // We hit the instantiation depth limit. Clear the exception specification
3153 // so that our callers don't have to cope with EST_Uninstantiated.
3154 FunctionProtoType::ExtProtoInfo EPI;
3155 EPI.ExceptionSpecType = EST_None;
3156 UpdateExceptionSpec(Decl, EPI);
3160 // Enter the scope of this instantiation. We don't use
3161 // PushDeclContext because we don't have a scope.
3162 Sema::ContextRAII savedContext(*this, Decl);
3163 LocalInstantiationScope Scope(*this);
3165 MultiLevelTemplateArgumentList TemplateArgs =
3166 getTemplateInstantiationArgs(Decl, nullptr, /*RelativeToPrimary*/true);
3168 FunctionDecl *Template = Proto->getExceptionSpecTemplate();
3169 addInstantiatedParametersToScope(*this, Decl, Template, Scope, TemplateArgs);
3171 ::InstantiateExceptionSpec(*this, Decl,
3172 Template->getType()->castAs<FunctionProtoType>(),
3176 /// \brief Initializes the common fields of an instantiation function
3177 /// declaration (New) from the corresponding fields of its template (Tmpl).
3179 /// \returns true if there was an error
3181 TemplateDeclInstantiator::InitFunctionInstantiation(FunctionDecl *New,
3182 FunctionDecl *Tmpl) {
3183 if (Tmpl->isDeleted())
3184 New->setDeletedAsWritten();
3186 // Forward the mangling number from the template to the instantiated decl.
3187 SemaRef.Context.setManglingNumber(New,
3188 SemaRef.Context.getManglingNumber(Tmpl));
3190 // If we are performing substituting explicitly-specified template arguments
3191 // or deduced template arguments into a function template and we reach this
3192 // point, we are now past the point where SFINAE applies and have committed
3193 // to keeping the new function template specialization. We therefore
3194 // convert the active template instantiation for the function template
3195 // into a template instantiation for this specific function template
3196 // specialization, which is not a SFINAE context, so that we diagnose any
3197 // further errors in the declaration itself.
3198 typedef Sema::ActiveTemplateInstantiation ActiveInstType;
3199 ActiveInstType &ActiveInst = SemaRef.ActiveTemplateInstantiations.back();
3200 if (ActiveInst.Kind == ActiveInstType::ExplicitTemplateArgumentSubstitution ||
3201 ActiveInst.Kind == ActiveInstType::DeducedTemplateArgumentSubstitution) {
3202 if (FunctionTemplateDecl *FunTmpl
3203 = dyn_cast<FunctionTemplateDecl>(ActiveInst.Entity)) {
3204 assert(FunTmpl->getTemplatedDecl() == Tmpl &&
3205 "Deduction from the wrong function template?");
3207 ActiveInst.Kind = ActiveInstType::TemplateInstantiation;
3208 ActiveInst.Entity = New;
3212 const FunctionProtoType *Proto = Tmpl->getType()->getAs<FunctionProtoType>();
3213 assert(Proto && "Function template without prototype?");
3215 if (Proto->hasExceptionSpec() || Proto->getNoReturnAttr()) {
3216 FunctionProtoType::ExtProtoInfo EPI = Proto->getExtProtoInfo();
3218 // DR1330: In C++11, defer instantiation of a non-trivial
3219 // exception specification.
3220 if (SemaRef.getLangOpts().CPlusPlus11 &&
3221 EPI.ExceptionSpecType != EST_None &&
3222 EPI.ExceptionSpecType != EST_DynamicNone &&
3223 EPI.ExceptionSpecType != EST_BasicNoexcept) {
3224 FunctionDecl *ExceptionSpecTemplate = Tmpl;
3225 if (EPI.ExceptionSpecType == EST_Uninstantiated)
3226 ExceptionSpecTemplate = EPI.ExceptionSpecTemplate;
3227 ExceptionSpecificationType NewEST = EST_Uninstantiated;
3228 if (EPI.ExceptionSpecType == EST_Unevaluated)
3229 NewEST = EST_Unevaluated;
3231 // Mark the function has having an uninstantiated exception specification.
3232 const FunctionProtoType *NewProto
3233 = New->getType()->getAs<FunctionProtoType>();
3234 assert(NewProto && "Template instantiation without function prototype?");
3235 EPI = NewProto->getExtProtoInfo();
3236 EPI.ExceptionSpecType = NewEST;
3237 EPI.ExceptionSpecDecl = New;
3238 EPI.ExceptionSpecTemplate = ExceptionSpecTemplate;
3239 New->setType(SemaRef.Context.getFunctionType(
3240 NewProto->getReturnType(), NewProto->getParamTypes(), EPI));
3242 ::InstantiateExceptionSpec(SemaRef, New, Proto, TemplateArgs);
3246 // Get the definition. Leaves the variable unchanged if undefined.
3247 const FunctionDecl *Definition = Tmpl;
3248 Tmpl->isDefined(Definition);
3250 SemaRef.InstantiateAttrs(TemplateArgs, Definition, New,
3251 LateAttrs, StartingScope);
3256 /// \brief Initializes common fields of an instantiated method
3257 /// declaration (New) from the corresponding fields of its template
3260 /// \returns true if there was an error
3262 TemplateDeclInstantiator::InitMethodInstantiation(CXXMethodDecl *New,
3263 CXXMethodDecl *Tmpl) {
3264 if (InitFunctionInstantiation(New, Tmpl))
3267 New->setAccess(Tmpl->getAccess());
3268 if (Tmpl->isVirtualAsWritten())
3269 New->setVirtualAsWritten(true);
3271 // FIXME: New needs a pointer to Tmpl
3275 /// \brief Instantiate the definition of the given function from its
3278 /// \param PointOfInstantiation the point at which the instantiation was
3279 /// required. Note that this is not precisely a "point of instantiation"
3280 /// for the function, but it's close.
3282 /// \param Function the already-instantiated declaration of a
3283 /// function template specialization or member function of a class template
3286 /// \param Recursive if true, recursively instantiates any functions that
3287 /// are required by this instantiation.
3289 /// \param DefinitionRequired if true, then we are performing an explicit
3290 /// instantiation where the body of the function is required. Complain if
3291 /// there is no such body.
3292 void Sema::InstantiateFunctionDefinition(SourceLocation PointOfInstantiation,
3293 FunctionDecl *Function,
3295 bool DefinitionRequired) {
3296 if (Function->isInvalidDecl() || Function->isDefined())
3299 // Never instantiate an explicit specialization except if it is a class scope
3300 // explicit specialization.
3301 if (Function->getTemplateSpecializationKind() == TSK_ExplicitSpecialization &&
3302 !Function->getClassScopeSpecializationPattern())
3305 // Find the function body that we'll be substituting.
3306 const FunctionDecl *PatternDecl = Function->getTemplateInstantiationPattern();
3307 assert(PatternDecl && "instantiating a non-template");
3309 Stmt *Pattern = PatternDecl->getBody(PatternDecl);
3310 assert(PatternDecl && "template definition is not a template");
3312 // Try to find a defaulted definition
3313 PatternDecl->isDefined(PatternDecl);
3315 assert(PatternDecl && "template definition is not a template");
3317 // Postpone late parsed template instantiations.
3318 if (PatternDecl->isLateTemplateParsed() &&
3319 !LateTemplateParser) {
3320 PendingInstantiations.push_back(
3321 std::make_pair(Function, PointOfInstantiation));
3325 // Call the LateTemplateParser callback if there is a need to late parse
3326 // a templated function definition.
3327 if (!Pattern && PatternDecl->isLateTemplateParsed() &&
3328 LateTemplateParser) {
3329 // FIXME: Optimize to allow individual templates to be deserialized.
3330 if (PatternDecl->isFromASTFile())
3331 ExternalSource->ReadLateParsedTemplates(LateParsedTemplateMap);
3333 LateParsedTemplate *LPT = LateParsedTemplateMap.lookup(PatternDecl);
3334 assert(LPT && "missing LateParsedTemplate");
3335 LateTemplateParser(OpaqueParser, *LPT);
3336 Pattern = PatternDecl->getBody(PatternDecl);
3339 if (!Pattern && !PatternDecl->isDefaulted()) {
3340 if (DefinitionRequired) {
3341 if (Function->getPrimaryTemplate())
3342 Diag(PointOfInstantiation,
3343 diag::err_explicit_instantiation_undefined_func_template)
3344 << Function->getPrimaryTemplate();
3346 Diag(PointOfInstantiation,
3347 diag::err_explicit_instantiation_undefined_member)
3348 << 1 << Function->getDeclName() << Function->getDeclContext();
3351 Diag(PatternDecl->getLocation(),
3352 diag::note_explicit_instantiation_here);
3353 Function->setInvalidDecl();
3354 } else if (Function->getTemplateSpecializationKind()
3355 == TSK_ExplicitInstantiationDefinition) {
3356 PendingInstantiations.push_back(
3357 std::make_pair(Function, PointOfInstantiation));
3363 // C++1y [temp.explicit]p10:
3364 // Except for inline functions, declarations with types deduced from their
3365 // initializer or return value, and class template specializations, other
3366 // explicit instantiation declarations have the effect of suppressing the
3367 // implicit instantiation of the entity to which they refer.
3368 if (Function->getTemplateSpecializationKind() ==
3369 TSK_ExplicitInstantiationDeclaration &&
3370 !PatternDecl->isInlined() &&
3371 !PatternDecl->getReturnType()->getContainedAutoType())
3374 if (PatternDecl->isInlined()) {
3375 // Function, and all later redeclarations of it (from imported modules,
3376 // for instance), are now implicitly inline.
3377 for (auto *D = Function->getMostRecentDecl(); /**/;
3378 D = D->getPreviousDecl()) {
3379 D->setImplicitlyInline();
3385 InstantiatingTemplate Inst(*this, PointOfInstantiation, Function);
3386 if (Inst.isInvalid())
3389 // Copy the inner loc start from the pattern.
3390 Function->setInnerLocStart(PatternDecl->getInnerLocStart());
3392 // If we're performing recursive template instantiation, create our own
3393 // queue of pending implicit instantiations that we will instantiate later,
3394 // while we're still within our own instantiation context.
3395 SmallVector<VTableUse, 16> SavedVTableUses;
3396 std::deque<PendingImplicitInstantiation> SavedPendingInstantiations;
3397 SavePendingLocalImplicitInstantiationsRAII
3398 SavedPendingLocalImplicitInstantiations(*this);
3400 VTableUses.swap(SavedVTableUses);
3401 PendingInstantiations.swap(SavedPendingInstantiations);
3404 EnterExpressionEvaluationContext EvalContext(*this,
3405 Sema::PotentiallyEvaluated);
3407 // Introduce a new scope where local variable instantiations will be
3408 // recorded, unless we're actually a member function within a local
3409 // class, in which case we need to merge our results with the parent
3410 // scope (of the enclosing function).
3411 bool MergeWithParentScope = false;
3412 if (CXXRecordDecl *Rec = dyn_cast<CXXRecordDecl>(Function->getDeclContext()))
3413 MergeWithParentScope = Rec->isLocalClass();
3415 LocalInstantiationScope Scope(*this, MergeWithParentScope);
3417 if (PatternDecl->isDefaulted())
3418 SetDeclDefaulted(Function, PatternDecl->getLocation());
3420 ActOnStartOfFunctionDef(nullptr, Function);
3422 // Enter the scope of this instantiation. We don't use
3423 // PushDeclContext because we don't have a scope.
3424 Sema::ContextRAII savedContext(*this, Function);
3426 MultiLevelTemplateArgumentList TemplateArgs =
3427 getTemplateInstantiationArgs(Function, nullptr, false, PatternDecl);
3429 addInstantiatedParametersToScope(*this, Function, PatternDecl, Scope,
3432 // If this is a constructor, instantiate the member initializers.
3433 if (const CXXConstructorDecl *Ctor =
3434 dyn_cast<CXXConstructorDecl>(PatternDecl)) {
3435 InstantiateMemInitializers(cast<CXXConstructorDecl>(Function), Ctor,
3439 // Instantiate the function body.
3440 StmtResult Body = SubstStmt(Pattern, TemplateArgs);
3442 if (Body.isInvalid())
3443 Function->setInvalidDecl();
3445 ActOnFinishFunctionBody(Function, Body.get(),
3446 /*IsInstantiation=*/true);
3448 PerformDependentDiagnostics(PatternDecl, TemplateArgs);
3450 if (auto *Listener = getASTMutationListener())
3451 Listener->FunctionDefinitionInstantiated(Function);
3456 DeclGroupRef DG(Function);
3457 Consumer.HandleTopLevelDecl(DG);
3459 // This class may have local implicit instantiations that need to be
3460 // instantiation within this scope.
3461 PerformPendingInstantiations(/*LocalOnly=*/true);
3465 // Define any pending vtables.
3466 DefineUsedVTables();
3468 // Instantiate any pending implicit instantiations found during the
3469 // instantiation of this template.
3470 PerformPendingInstantiations();
3472 // Restore the set of pending vtables.
3473 assert(VTableUses.empty() &&
3474 "VTableUses should be empty before it is discarded.");
3475 VTableUses.swap(SavedVTableUses);
3477 // Restore the set of pending implicit instantiations.
3478 assert(PendingInstantiations.empty() &&
3479 "PendingInstantiations should be empty before it is discarded.");
3480 PendingInstantiations.swap(SavedPendingInstantiations);
3484 VarTemplateSpecializationDecl *Sema::BuildVarTemplateInstantiation(
3485 VarTemplateDecl *VarTemplate, VarDecl *FromVar,
3486 const TemplateArgumentList &TemplateArgList,
3487 const TemplateArgumentListInfo &TemplateArgsInfo,
3488 SmallVectorImpl<TemplateArgument> &Converted,
3489 SourceLocation PointOfInstantiation, void *InsertPos,
3490 LateInstantiatedAttrVec *LateAttrs,
3491 LocalInstantiationScope *StartingScope) {
3492 if (FromVar->isInvalidDecl())
3495 InstantiatingTemplate Inst(*this, PointOfInstantiation, FromVar);
3496 if (Inst.isInvalid())
3499 MultiLevelTemplateArgumentList TemplateArgLists;
3500 TemplateArgLists.addOuterTemplateArguments(&TemplateArgList);
3502 // Instantiate the first declaration of the variable template: for a partial
3503 // specialization of a static data member template, the first declaration may
3504 // or may not be the declaration in the class; if it's in the class, we want
3505 // to instantiate a member in the class (a declaration), and if it's outside,
3506 // we want to instantiate a definition.
3508 // If we're instantiating an explicitly-specialized member template or member
3509 // partial specialization, don't do this. The member specialization completely
3510 // replaces the original declaration in this case.
3511 bool IsMemberSpec = false;
3512 if (VarTemplatePartialSpecializationDecl *PartialSpec =
3513 dyn_cast<VarTemplatePartialSpecializationDecl>(FromVar))
3514 IsMemberSpec = PartialSpec->isMemberSpecialization();
3515 else if (VarTemplateDecl *FromTemplate = FromVar->getDescribedVarTemplate())
3516 IsMemberSpec = FromTemplate->isMemberSpecialization();
3518 FromVar = FromVar->getFirstDecl();
3520 MultiLevelTemplateArgumentList MultiLevelList(TemplateArgList);
3521 TemplateDeclInstantiator Instantiator(*this, FromVar->getDeclContext(),
3524 // TODO: Set LateAttrs and StartingScope ...
3526 return cast_or_null<VarTemplateSpecializationDecl>(
3527 Instantiator.VisitVarTemplateSpecializationDecl(
3528 VarTemplate, FromVar, InsertPos, TemplateArgsInfo, Converted));
3531 /// \brief Instantiates a variable template specialization by completing it
3532 /// with appropriate type information and initializer.
3533 VarTemplateSpecializationDecl *Sema::CompleteVarTemplateSpecializationDecl(
3534 VarTemplateSpecializationDecl *VarSpec, VarDecl *PatternDecl,
3535 const MultiLevelTemplateArgumentList &TemplateArgs) {
3537 // Do substitution on the type of the declaration
3538 TypeSourceInfo *DI =
3539 SubstType(PatternDecl->getTypeSourceInfo(), TemplateArgs,
3540 PatternDecl->getTypeSpecStartLoc(), PatternDecl->getDeclName());
3544 // Update the type of this variable template specialization.
3545 VarSpec->setType(DI->getType());
3547 // Instantiate the initializer.
3548 InstantiateVariableInitializer(VarSpec, PatternDecl, TemplateArgs);
3553 /// BuildVariableInstantiation - Used after a new variable has been created.
3554 /// Sets basic variable data and decides whether to postpone the
3555 /// variable instantiation.
3556 void Sema::BuildVariableInstantiation(
3557 VarDecl *NewVar, VarDecl *OldVar,
3558 const MultiLevelTemplateArgumentList &TemplateArgs,
3559 LateInstantiatedAttrVec *LateAttrs, DeclContext *Owner,
3560 LocalInstantiationScope *StartingScope,
3561 bool InstantiatingVarTemplate) {
3563 // If we are instantiating a local extern declaration, the
3564 // instantiation belongs lexically to the containing function.
3565 // If we are instantiating a static data member defined
3566 // out-of-line, the instantiation will have the same lexical
3567 // context (which will be a namespace scope) as the template.
3568 if (OldVar->isLocalExternDecl()) {
3569 NewVar->setLocalExternDecl();
3570 NewVar->setLexicalDeclContext(Owner);
3571 } else if (OldVar->isOutOfLine())
3572 NewVar->setLexicalDeclContext(OldVar->getLexicalDeclContext());
3573 NewVar->setTSCSpec(OldVar->getTSCSpec());
3574 NewVar->setInitStyle(OldVar->getInitStyle());
3575 NewVar->setCXXForRangeDecl(OldVar->isCXXForRangeDecl());
3576 NewVar->setConstexpr(OldVar->isConstexpr());
3577 NewVar->setInitCapture(OldVar->isInitCapture());
3578 NewVar->setPreviousDeclInSameBlockScope(
3579 OldVar->isPreviousDeclInSameBlockScope());
3580 NewVar->setAccess(OldVar->getAccess());
3582 if (!OldVar->isStaticDataMember()) {
3583 if (OldVar->isUsed(false))
3584 NewVar->setIsUsed();
3585 NewVar->setReferenced(OldVar->isReferenced());
3588 // See if the old variable had a type-specifier that defined an anonymous tag.
3589 // If it did, mark the new variable as being the declarator for the new
3591 if (const TagType *OldTagType = OldVar->getType()->getAs<TagType>()) {
3592 TagDecl *OldTag = OldTagType->getDecl();
3593 if (OldTag->getDeclaratorForAnonDecl() == OldVar) {
3594 TagDecl *NewTag = NewVar->getType()->castAs<TagType>()->getDecl();
3595 assert(!NewTag->hasNameForLinkage() &&
3596 !NewTag->hasDeclaratorForAnonDecl());
3597 NewTag->setDeclaratorForAnonDecl(NewVar);
3601 InstantiateAttrs(TemplateArgs, OldVar, NewVar, LateAttrs, StartingScope);
3603 LookupResult Previous(
3604 *this, NewVar->getDeclName(), NewVar->getLocation(),
3605 NewVar->isLocalExternDecl() ? Sema::LookupRedeclarationWithLinkage
3606 : Sema::LookupOrdinaryName,
3607 Sema::ForRedeclaration);
3609 if (NewVar->isLocalExternDecl() && OldVar->getPreviousDecl() &&
3610 (!OldVar->getPreviousDecl()->getDeclContext()->isDependentContext() ||
3611 OldVar->getPreviousDecl()->getDeclContext()==OldVar->getDeclContext())) {
3612 // We have a previous declaration. Use that one, so we merge with the
3614 if (NamedDecl *NewPrev = FindInstantiatedDecl(
3615 NewVar->getLocation(), OldVar->getPreviousDecl(), TemplateArgs))
3616 Previous.addDecl(NewPrev);
3617 } else if (!isa<VarTemplateSpecializationDecl>(NewVar) &&
3618 OldVar->hasLinkage())
3619 LookupQualifiedName(Previous, NewVar->getDeclContext(), false);
3620 CheckVariableDeclaration(NewVar, Previous);
3622 if (!InstantiatingVarTemplate) {
3623 NewVar->getLexicalDeclContext()->addHiddenDecl(NewVar);
3624 if (!NewVar->isLocalExternDecl() || !NewVar->getPreviousDecl())
3625 NewVar->getDeclContext()->makeDeclVisibleInContext(NewVar);
3628 if (!OldVar->isOutOfLine()) {
3629 if (NewVar->getDeclContext()->isFunctionOrMethod())
3630 CurrentInstantiationScope->InstantiatedLocal(OldVar, NewVar);
3633 // Link instantiations of static data members back to the template from
3634 // which they were instantiated.
3635 if (NewVar->isStaticDataMember() && !InstantiatingVarTemplate)
3636 NewVar->setInstantiationOfStaticDataMember(OldVar,
3637 TSK_ImplicitInstantiation);
3639 // Forward the mangling number from the template to the instantiated decl.
3640 Context.setManglingNumber(NewVar, Context.getManglingNumber(OldVar));
3641 Context.setStaticLocalNumber(NewVar, Context.getStaticLocalNumber(OldVar));
3643 // Delay instantiation of the initializer for variable templates until a
3644 // definition of the variable is needed. We need it right away if the type
3646 if ((!isa<VarTemplateSpecializationDecl>(NewVar) &&
3647 !InstantiatingVarTemplate) ||
3648 NewVar->getType()->isUndeducedType())
3649 InstantiateVariableInitializer(NewVar, OldVar, TemplateArgs);
3651 // Diagnose unused local variables with dependent types, where the diagnostic
3652 // will have been deferred.
3653 if (!NewVar->isInvalidDecl() &&
3654 NewVar->getDeclContext()->isFunctionOrMethod() && !NewVar->isUsed() &&
3655 OldVar->getType()->isDependentType())
3656 DiagnoseUnusedDecl(NewVar);
3659 /// \brief Instantiate the initializer of a variable.
3660 void Sema::InstantiateVariableInitializer(
3661 VarDecl *Var, VarDecl *OldVar,
3662 const MultiLevelTemplateArgumentList &TemplateArgs) {
3664 if (Var->getAnyInitializer())
3665 // We already have an initializer in the class.
3668 if (OldVar->getInit()) {
3669 if (Var->isStaticDataMember() && !OldVar->isOutOfLine())
3670 PushExpressionEvaluationContext(Sema::ConstantEvaluated, OldVar);
3672 PushExpressionEvaluationContext(Sema::PotentiallyEvaluated, OldVar);
3674 // Instantiate the initializer.
3676 SubstInitializer(OldVar->getInit(), TemplateArgs,
3677 OldVar->getInitStyle() == VarDecl::CallInit);
3678 if (!Init.isInvalid()) {
3679 bool TypeMayContainAuto = true;
3680 Expr *InitExpr = Init.get();
3682 if (Var->hasAttr<DLLImportAttr>() &&
3684 !InitExpr->isConstantInitializer(getASTContext(), false))) {
3685 // Do not dynamically initialize dllimport variables.
3686 } else if (InitExpr) {
3687 bool DirectInit = OldVar->isDirectInit();
3688 AddInitializerToDecl(Var, InitExpr, DirectInit, TypeMayContainAuto);
3690 ActOnUninitializedDecl(Var, TypeMayContainAuto);
3692 // FIXME: Not too happy about invalidating the declaration
3693 // because of a bogus initializer.
3694 Var->setInvalidDecl();
3697 PopExpressionEvaluationContext();
3698 } else if ((!Var->isStaticDataMember() || Var->isOutOfLine()) &&
3699 !Var->isCXXForRangeDecl())
3700 ActOnUninitializedDecl(Var, false);
3703 /// \brief Instantiate the definition of the given variable from its
3706 /// \param PointOfInstantiation the point at which the instantiation was
3707 /// required. Note that this is not precisely a "point of instantiation"
3708 /// for the function, but it's close.
3710 /// \param Var the already-instantiated declaration of a static member
3711 /// variable of a class template specialization.
3713 /// \param Recursive if true, recursively instantiates any functions that
3714 /// are required by this instantiation.
3716 /// \param DefinitionRequired if true, then we are performing an explicit
3717 /// instantiation where an out-of-line definition of the member variable
3718 /// is required. Complain if there is no such definition.
3719 void Sema::InstantiateStaticDataMemberDefinition(
3720 SourceLocation PointOfInstantiation,
3723 bool DefinitionRequired) {
3724 InstantiateVariableDefinition(PointOfInstantiation, Var, Recursive,
3725 DefinitionRequired);
3728 void Sema::InstantiateVariableDefinition(SourceLocation PointOfInstantiation,
3729 VarDecl *Var, bool Recursive,
3730 bool DefinitionRequired) {
3731 if (Var->isInvalidDecl())
3734 VarTemplateSpecializationDecl *VarSpec =
3735 dyn_cast<VarTemplateSpecializationDecl>(Var);
3736 VarDecl *PatternDecl = nullptr, *Def = nullptr;
3737 MultiLevelTemplateArgumentList TemplateArgs =
3738 getTemplateInstantiationArgs(Var);
3741 // If this is a variable template specialization, make sure that it is
3742 // non-dependent, then find its instantiation pattern.
3743 bool InstantiationDependent = false;
3744 assert(!TemplateSpecializationType::anyDependentTemplateArguments(
3745 VarSpec->getTemplateArgsInfo(), InstantiationDependent) &&
3746 "Only instantiate variable template specializations that are "
3747 "not type-dependent");
3748 (void)InstantiationDependent;
3750 // Find the variable initialization that we'll be substituting. If the
3751 // pattern was instantiated from a member template, look back further to
3752 // find the real pattern.
3753 assert(VarSpec->getSpecializedTemplate() &&
3754 "Specialization without specialized template?");
3755 llvm::PointerUnion<VarTemplateDecl *,
3756 VarTemplatePartialSpecializationDecl *> PatternPtr =
3757 VarSpec->getSpecializedTemplateOrPartial();
3758 if (PatternPtr.is<VarTemplatePartialSpecializationDecl *>()) {
3759 VarTemplatePartialSpecializationDecl *Tmpl =
3760 PatternPtr.get<VarTemplatePartialSpecializationDecl *>();
3761 while (VarTemplatePartialSpecializationDecl *From =
3762 Tmpl->getInstantiatedFromMember()) {
3763 if (Tmpl->isMemberSpecialization())
3770 VarTemplateDecl *Tmpl = PatternPtr.get<VarTemplateDecl *>();
3771 while (VarTemplateDecl *From =
3772 Tmpl->getInstantiatedFromMemberTemplate()) {
3773 if (Tmpl->isMemberSpecialization())
3778 PatternDecl = Tmpl->getTemplatedDecl();
3781 // If this is a static data member template, there might be an
3782 // uninstantiated initializer on the declaration. If so, instantiate
3784 if (PatternDecl->isStaticDataMember() &&
3785 (PatternDecl = PatternDecl->getFirstDecl())->hasInit() &&
3787 // FIXME: Factor out the duplicated instantiation context setup/tear down
3789 InstantiatingTemplate Inst(*this, PointOfInstantiation, Var);
3790 if (Inst.isInvalid())
3793 // If we're performing recursive template instantiation, create our own
3794 // queue of pending implicit instantiations that we will instantiate
3795 // later, while we're still within our own instantiation context.
3796 SmallVector<VTableUse, 16> SavedVTableUses;
3797 std::deque<PendingImplicitInstantiation> SavedPendingInstantiations;
3799 VTableUses.swap(SavedVTableUses);
3800 PendingInstantiations.swap(SavedPendingInstantiations);
3803 LocalInstantiationScope Local(*this);
3805 // Enter the scope of this instantiation. We don't use
3806 // PushDeclContext because we don't have a scope.
3807 ContextRAII PreviousContext(*this, Var->getDeclContext());
3808 InstantiateVariableInitializer(Var, PatternDecl, TemplateArgs);
3809 PreviousContext.pop();
3811 // FIXME: Need to inform the ASTConsumer that we instantiated the
3814 // This variable may have local implicit instantiations that need to be
3815 // instantiated within this scope.
3816 PerformPendingInstantiations(/*LocalOnly=*/true);
3821 // Define any newly required vtables.
3822 DefineUsedVTables();
3824 // Instantiate any pending implicit instantiations found during the
3825 // instantiation of this template.
3826 PerformPendingInstantiations();
3828 // Restore the set of pending vtables.
3829 assert(VTableUses.empty() &&
3830 "VTableUses should be empty before it is discarded.");
3831 VTableUses.swap(SavedVTableUses);
3833 // Restore the set of pending implicit instantiations.
3834 assert(PendingInstantiations.empty() &&
3835 "PendingInstantiations should be empty before it is discarded.");
3836 PendingInstantiations.swap(SavedPendingInstantiations);
3840 // Find actual definition
3841 Def = PatternDecl->getDefinition(getASTContext());
3843 // If this is a static data member, find its out-of-line definition.
3844 assert(Var->isStaticDataMember() && "not a static data member?");
3845 PatternDecl = Var->getInstantiatedFromStaticDataMember();
3847 assert(PatternDecl && "data member was not instantiated from a template?");
3848 assert(PatternDecl->isStaticDataMember() && "not a static data member?");
3849 Def = PatternDecl->getOutOfLineDefinition();
3852 // If we don't have a definition of the variable template, we won't perform
3853 // any instantiation. Rather, we rely on the user to instantiate this
3854 // definition (or provide a specialization for it) in another translation
3857 if (DefinitionRequired) {
3859 Diag(PointOfInstantiation,
3860 diag::err_explicit_instantiation_undefined_var_template) << Var;
3862 Diag(PointOfInstantiation,
3863 diag::err_explicit_instantiation_undefined_member)
3864 << 2 << Var->getDeclName() << Var->getDeclContext();
3865 Diag(PatternDecl->getLocation(),
3866 diag::note_explicit_instantiation_here);
3868 Var->setInvalidDecl();
3869 } else if (Var->getTemplateSpecializationKind()
3870 == TSK_ExplicitInstantiationDefinition) {
3871 PendingInstantiations.push_back(
3872 std::make_pair(Var, PointOfInstantiation));
3878 TemplateSpecializationKind TSK = Var->getTemplateSpecializationKind();
3880 // Never instantiate an explicit specialization.
3881 if (TSK == TSK_ExplicitSpecialization)
3884 // C++11 [temp.explicit]p10:
3885 // Except for inline functions, [...] explicit instantiation declarations
3886 // have the effect of suppressing the implicit instantiation of the entity
3887 // to which they refer.
3888 if (TSK == TSK_ExplicitInstantiationDeclaration)
3891 // Make sure to pass the instantiated variable to the consumer at the end.
3892 struct PassToConsumerRAII {
3893 ASTConsumer &Consumer;
3896 PassToConsumerRAII(ASTConsumer &Consumer, VarDecl *Var)
3897 : Consumer(Consumer), Var(Var) { }
3899 ~PassToConsumerRAII() {
3900 Consumer.HandleCXXStaticMemberVarInstantiation(Var);
3902 } PassToConsumerRAII(Consumer, Var);
3904 // If we already have a definition, we're done.
3905 if (VarDecl *Def = Var->getDefinition()) {
3906 // We may be explicitly instantiating something we've already implicitly
3908 Def->setTemplateSpecializationKind(Var->getTemplateSpecializationKind(),
3909 PointOfInstantiation);
3913 InstantiatingTemplate Inst(*this, PointOfInstantiation, Var);
3914 if (Inst.isInvalid())
3917 // If we're performing recursive template instantiation, create our own
3918 // queue of pending implicit instantiations that we will instantiate later,
3919 // while we're still within our own instantiation context.
3920 SmallVector<VTableUse, 16> SavedVTableUses;
3921 std::deque<PendingImplicitInstantiation> SavedPendingInstantiations;
3922 SavePendingLocalImplicitInstantiationsRAII
3923 SavedPendingLocalImplicitInstantiations(*this);
3925 VTableUses.swap(SavedVTableUses);
3926 PendingInstantiations.swap(SavedPendingInstantiations);
3929 // Enter the scope of this instantiation. We don't use
3930 // PushDeclContext because we don't have a scope.
3931 ContextRAII PreviousContext(*this, Var->getDeclContext());
3932 LocalInstantiationScope Local(*this);
3934 VarDecl *OldVar = Var;
3936 Var = cast_or_null<VarDecl>(SubstDecl(Def, Var->getDeclContext(),
3938 else if (Var->isStaticDataMember() &&
3939 Var->getLexicalDeclContext()->isRecord()) {
3940 // We need to instantiate the definition of a static data member template,
3941 // and all we have is the in-class declaration of it. Instantiate a separate
3942 // declaration of the definition.
3943 TemplateDeclInstantiator Instantiator(*this, Var->getDeclContext(),
3945 Var = cast_or_null<VarDecl>(Instantiator.VisitVarTemplateSpecializationDecl(
3946 VarSpec->getSpecializedTemplate(), Def, nullptr,
3947 VarSpec->getTemplateArgsInfo(), VarSpec->getTemplateArgs().asArray()));
3949 llvm::PointerUnion<VarTemplateDecl *,
3950 VarTemplatePartialSpecializationDecl *> PatternPtr =
3951 VarSpec->getSpecializedTemplateOrPartial();
3952 if (VarTemplatePartialSpecializationDecl *Partial =
3953 PatternPtr.dyn_cast<VarTemplatePartialSpecializationDecl *>())
3954 cast<VarTemplateSpecializationDecl>(Var)->setInstantiationOf(
3955 Partial, &VarSpec->getTemplateInstantiationArgs());
3957 // Merge the definition with the declaration.
3958 LookupResult R(*this, Var->getDeclName(), Var->getLocation(),
3959 LookupOrdinaryName, ForRedeclaration);
3961 MergeVarDecl(Var, R);
3963 // Attach the initializer.
3964 InstantiateVariableInitializer(Var, Def, TemplateArgs);
3967 // Complete the existing variable's definition with an appropriately
3968 // substituted type and initializer.
3969 Var = CompleteVarTemplateSpecializationDecl(VarSpec, Def, TemplateArgs);
3971 PreviousContext.pop();
3974 PassToConsumerRAII.Var = Var;
3975 Var->setTemplateSpecializationKind(OldVar->getTemplateSpecializationKind(),
3976 OldVar->getPointOfInstantiation());
3979 // This variable may have local implicit instantiations that need to be
3980 // instantiated within this scope.
3981 PerformPendingInstantiations(/*LocalOnly=*/true);
3986 // Define any newly required vtables.
3987 DefineUsedVTables();
3989 // Instantiate any pending implicit instantiations found during the
3990 // instantiation of this template.
3991 PerformPendingInstantiations();
3993 // Restore the set of pending vtables.
3994 assert(VTableUses.empty() &&
3995 "VTableUses should be empty before it is discarded.");
3996 VTableUses.swap(SavedVTableUses);
3998 // Restore the set of pending implicit instantiations.
3999 assert(PendingInstantiations.empty() &&
4000 "PendingInstantiations should be empty before it is discarded.");
4001 PendingInstantiations.swap(SavedPendingInstantiations);
4006 Sema::InstantiateMemInitializers(CXXConstructorDecl *New,
4007 const CXXConstructorDecl *Tmpl,
4008 const MultiLevelTemplateArgumentList &TemplateArgs) {
4010 SmallVector<CXXCtorInitializer*, 4> NewInits;
4011 bool AnyErrors = Tmpl->isInvalidDecl();
4013 // Instantiate all the initializers.
4014 for (const auto *Init : Tmpl->inits()) {
4015 // Only instantiate written initializers, let Sema re-construct implicit
4017 if (!Init->isWritten())
4020 SourceLocation EllipsisLoc;
4022 if (Init->isPackExpansion()) {
4023 // This is a pack expansion. We should expand it now.
4024 TypeLoc BaseTL = Init->getTypeSourceInfo()->getTypeLoc();
4025 SmallVector<UnexpandedParameterPack, 4> Unexpanded;
4026 collectUnexpandedParameterPacks(BaseTL, Unexpanded);
4027 collectUnexpandedParameterPacks(Init->getInit(), Unexpanded);
4028 bool ShouldExpand = false;
4029 bool RetainExpansion = false;
4030 Optional<unsigned> NumExpansions;
4031 if (CheckParameterPacksForExpansion(Init->getEllipsisLoc(),
4032 BaseTL.getSourceRange(),
4034 TemplateArgs, ShouldExpand,
4038 New->setInvalidDecl();
4041 assert(ShouldExpand && "Partial instantiation of base initializer?");
4043 // Loop over all of the arguments in the argument pack(s),
4044 for (unsigned I = 0; I != *NumExpansions; ++I) {
4045 Sema::ArgumentPackSubstitutionIndexRAII SubstIndex(*this, I);
4047 // Instantiate the initializer.
4048 ExprResult TempInit = SubstInitializer(Init->getInit(), TemplateArgs,
4049 /*CXXDirectInit=*/true);
4050 if (TempInit.isInvalid()) {
4055 // Instantiate the base type.
4056 TypeSourceInfo *BaseTInfo = SubstType(Init->getTypeSourceInfo(),
4058 Init->getSourceLocation(),
4059 New->getDeclName());
4065 // Build the initializer.
4066 MemInitResult NewInit = BuildBaseInitializer(BaseTInfo->getType(),
4067 BaseTInfo, TempInit.get(),
4070 if (NewInit.isInvalid()) {
4075 NewInits.push_back(NewInit.get());
4081 // Instantiate the initializer.
4082 ExprResult TempInit = SubstInitializer(Init->getInit(), TemplateArgs,
4083 /*CXXDirectInit=*/true);
4084 if (TempInit.isInvalid()) {
4089 MemInitResult NewInit;
4090 if (Init->isDelegatingInitializer() || Init->isBaseInitializer()) {
4091 TypeSourceInfo *TInfo = SubstType(Init->getTypeSourceInfo(),
4093 Init->getSourceLocation(),
4094 New->getDeclName());
4097 New->setInvalidDecl();
4101 if (Init->isBaseInitializer())
4102 NewInit = BuildBaseInitializer(TInfo->getType(), TInfo, TempInit.get(),
4103 New->getParent(), EllipsisLoc);
4105 NewInit = BuildDelegatingInitializer(TInfo, TempInit.get(),
4106 cast<CXXRecordDecl>(CurContext->getParent()));
4107 } else if (Init->isMemberInitializer()) {
4108 FieldDecl *Member = cast_or_null<FieldDecl>(FindInstantiatedDecl(
4109 Init->getMemberLocation(),
4114 New->setInvalidDecl();
4118 NewInit = BuildMemberInitializer(Member, TempInit.get(),
4119 Init->getSourceLocation());
4120 } else if (Init->isIndirectMemberInitializer()) {
4121 IndirectFieldDecl *IndirectMember =
4122 cast_or_null<IndirectFieldDecl>(FindInstantiatedDecl(
4123 Init->getMemberLocation(),
4124 Init->getIndirectMember(), TemplateArgs));
4126 if (!IndirectMember) {
4128 New->setInvalidDecl();
4132 NewInit = BuildMemberInitializer(IndirectMember, TempInit.get(),
4133 Init->getSourceLocation());
4136 if (NewInit.isInvalid()) {
4138 New->setInvalidDecl();
4140 NewInits.push_back(NewInit.get());
4144 // Assign all the initializers to the new constructor.
4145 ActOnMemInitializers(New,
4146 /*FIXME: ColonLoc */
4152 // TODO: this could be templated if the various decl types used the
4153 // same method name.
4154 static bool isInstantiationOf(ClassTemplateDecl *Pattern,
4155 ClassTemplateDecl *Instance) {
4156 Pattern = Pattern->getCanonicalDecl();
4159 Instance = Instance->getCanonicalDecl();
4160 if (Pattern == Instance) return true;
4161 Instance = Instance->getInstantiatedFromMemberTemplate();
4167 static bool isInstantiationOf(FunctionTemplateDecl *Pattern,
4168 FunctionTemplateDecl *Instance) {
4169 Pattern = Pattern->getCanonicalDecl();
4172 Instance = Instance->getCanonicalDecl();
4173 if (Pattern == Instance) return true;
4174 Instance = Instance->getInstantiatedFromMemberTemplate();
4181 isInstantiationOf(ClassTemplatePartialSpecializationDecl *Pattern,
4182 ClassTemplatePartialSpecializationDecl *Instance) {
4184 = cast<ClassTemplatePartialSpecializationDecl>(Pattern->getCanonicalDecl());
4186 Instance = cast<ClassTemplatePartialSpecializationDecl>(
4187 Instance->getCanonicalDecl());
4188 if (Pattern == Instance)
4190 Instance = Instance->getInstantiatedFromMember();
4196 static bool isInstantiationOf(CXXRecordDecl *Pattern,
4197 CXXRecordDecl *Instance) {
4198 Pattern = Pattern->getCanonicalDecl();
4201 Instance = Instance->getCanonicalDecl();
4202 if (Pattern == Instance) return true;
4203 Instance = Instance->getInstantiatedFromMemberClass();
4209 static bool isInstantiationOf(FunctionDecl *Pattern,
4210 FunctionDecl *Instance) {
4211 Pattern = Pattern->getCanonicalDecl();
4214 Instance = Instance->getCanonicalDecl();
4215 if (Pattern == Instance) return true;
4216 Instance = Instance->getInstantiatedFromMemberFunction();
4222 static bool isInstantiationOf(EnumDecl *Pattern,
4223 EnumDecl *Instance) {
4224 Pattern = Pattern->getCanonicalDecl();
4227 Instance = Instance->getCanonicalDecl();
4228 if (Pattern == Instance) return true;
4229 Instance = Instance->getInstantiatedFromMemberEnum();
4235 static bool isInstantiationOf(UsingShadowDecl *Pattern,
4236 UsingShadowDecl *Instance,
4238 return C.getInstantiatedFromUsingShadowDecl(Instance) == Pattern;
4241 static bool isInstantiationOf(UsingDecl *Pattern,
4242 UsingDecl *Instance,
4244 return C.getInstantiatedFromUsingDecl(Instance) == Pattern;
4247 static bool isInstantiationOf(UnresolvedUsingValueDecl *Pattern,
4248 UsingDecl *Instance,
4250 return C.getInstantiatedFromUsingDecl(Instance) == Pattern;
4253 static bool isInstantiationOf(UnresolvedUsingTypenameDecl *Pattern,
4254 UsingDecl *Instance,
4256 return C.getInstantiatedFromUsingDecl(Instance) == Pattern;
4259 static bool isInstantiationOfStaticDataMember(VarDecl *Pattern,
4260 VarDecl *Instance) {
4261 assert(Instance->isStaticDataMember());
4263 Pattern = Pattern->getCanonicalDecl();
4266 Instance = Instance->getCanonicalDecl();
4267 if (Pattern == Instance) return true;
4268 Instance = Instance->getInstantiatedFromStaticDataMember();
4274 // Other is the prospective instantiation
4275 // D is the prospective pattern
4276 static bool isInstantiationOf(ASTContext &Ctx, NamedDecl *D, Decl *Other) {
4277 if (D->getKind() != Other->getKind()) {
4278 if (UnresolvedUsingTypenameDecl *UUD
4279 = dyn_cast<UnresolvedUsingTypenameDecl>(D)) {
4280 if (UsingDecl *UD = dyn_cast<UsingDecl>(Other)) {
4281 return isInstantiationOf(UUD, UD, Ctx);
4285 if (UnresolvedUsingValueDecl *UUD
4286 = dyn_cast<UnresolvedUsingValueDecl>(D)) {
4287 if (UsingDecl *UD = dyn_cast<UsingDecl>(Other)) {
4288 return isInstantiationOf(UUD, UD, Ctx);
4295 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Other))
4296 return isInstantiationOf(cast<CXXRecordDecl>(D), Record);
4298 if (FunctionDecl *Function = dyn_cast<FunctionDecl>(Other))
4299 return isInstantiationOf(cast<FunctionDecl>(D), Function);
4301 if (EnumDecl *Enum = dyn_cast<EnumDecl>(Other))
4302 return isInstantiationOf(cast<EnumDecl>(D), Enum);
4304 if (VarDecl *Var = dyn_cast<VarDecl>(Other))
4305 if (Var->isStaticDataMember())
4306 return isInstantiationOfStaticDataMember(cast<VarDecl>(D), Var);
4308 if (ClassTemplateDecl *Temp = dyn_cast<ClassTemplateDecl>(Other))
4309 return isInstantiationOf(cast<ClassTemplateDecl>(D), Temp);
4311 if (FunctionTemplateDecl *Temp = dyn_cast<FunctionTemplateDecl>(Other))
4312 return isInstantiationOf(cast<FunctionTemplateDecl>(D), Temp);
4314 if (ClassTemplatePartialSpecializationDecl *PartialSpec
4315 = dyn_cast<ClassTemplatePartialSpecializationDecl>(Other))
4316 return isInstantiationOf(cast<ClassTemplatePartialSpecializationDecl>(D),
4319 if (FieldDecl *Field = dyn_cast<FieldDecl>(Other)) {
4320 if (!Field->getDeclName()) {
4321 // This is an unnamed field.
4322 return Ctx.getInstantiatedFromUnnamedFieldDecl(Field) ==
4327 if (UsingDecl *Using = dyn_cast<UsingDecl>(Other))
4328 return isInstantiationOf(cast<UsingDecl>(D), Using, Ctx);
4330 if (UsingShadowDecl *Shadow = dyn_cast<UsingShadowDecl>(Other))
4331 return isInstantiationOf(cast<UsingShadowDecl>(D), Shadow, Ctx);
4333 return D->getDeclName() && isa<NamedDecl>(Other) &&
4334 D->getDeclName() == cast<NamedDecl>(Other)->getDeclName();
4337 template<typename ForwardIterator>
4338 static NamedDecl *findInstantiationOf(ASTContext &Ctx,
4340 ForwardIterator first,
4341 ForwardIterator last) {
4342 for (; first != last; ++first)
4343 if (isInstantiationOf(Ctx, D, *first))
4344 return cast<NamedDecl>(*first);
4349 /// \brief Finds the instantiation of the given declaration context
4350 /// within the current instantiation.
4352 /// \returns NULL if there was an error
4353 DeclContext *Sema::FindInstantiatedContext(SourceLocation Loc, DeclContext* DC,
4354 const MultiLevelTemplateArgumentList &TemplateArgs) {
4355 if (NamedDecl *D = dyn_cast<NamedDecl>(DC)) {
4356 Decl* ID = FindInstantiatedDecl(Loc, D, TemplateArgs);
4357 return cast_or_null<DeclContext>(ID);
4361 /// \brief Find the instantiation of the given declaration within the
4362 /// current instantiation.
4364 /// This routine is intended to be used when \p D is a declaration
4365 /// referenced from within a template, that needs to mapped into the
4366 /// corresponding declaration within an instantiation. For example,
4370 /// template<typename T>
4373 /// KnownValue = sizeof(T)
4376 /// bool getKind() const { return KnownValue; }
4379 /// template struct X<int>;
4382 /// In the instantiation of <tt>X<int>::getKind()</tt>, we need to map the
4383 /// \p EnumConstantDecl for \p KnownValue (which refers to
4384 /// <tt>X<T>::<Kind>::KnownValue</tt>) to its instantiation
4385 /// (<tt>X<int>::<Kind>::KnownValue</tt>). \p FindInstantiatedDecl performs
4386 /// this mapping from within the instantiation of <tt>X<int></tt>.
4387 NamedDecl *Sema::FindInstantiatedDecl(SourceLocation Loc, NamedDecl *D,
4388 const MultiLevelTemplateArgumentList &TemplateArgs) {
4389 DeclContext *ParentDC = D->getDeclContext();
4390 // FIXME: Parmeters of pointer to functions (y below) that are themselves
4391 // parameters (p below) can have their ParentDC set to the translation-unit
4392 // - thus we can not consistently check if the ParentDC of such a parameter
4393 // is Dependent or/and a FunctionOrMethod.
4394 // For e.g. this code, during Template argument deduction tries to
4395 // find an instantiated decl for (T y) when the ParentDC for y is
4396 // the translation unit.
4397 // e.g. template <class T> void Foo(auto (*p)(T y) -> decltype(y())) {}
4398 // float baz(float(*)()) { return 0.0; }
4400 // The better fix here is perhaps to ensure that a ParmVarDecl, by the time
4401 // it gets here, always has a FunctionOrMethod as its ParentDC??
4403 // - as long as we have a ParmVarDecl whose parent is non-dependent and
4404 // whose type is not instantiation dependent, do nothing to the decl
4405 // - otherwise find its instantiated decl.
4406 if (isa<ParmVarDecl>(D) && !ParentDC->isDependentContext() &&
4407 !cast<ParmVarDecl>(D)->getType()->isInstantiationDependentType())
4409 if (isa<ParmVarDecl>(D) || isa<NonTypeTemplateParmDecl>(D) ||
4410 isa<TemplateTypeParmDecl>(D) || isa<TemplateTemplateParmDecl>(D) ||
4411 (ParentDC->isFunctionOrMethod() && ParentDC->isDependentContext()) ||
4412 (isa<CXXRecordDecl>(D) && cast<CXXRecordDecl>(D)->isLambda())) {
4413 // D is a local of some kind. Look into the map of local
4414 // declarations to their instantiations.
4415 typedef LocalInstantiationScope::DeclArgumentPack DeclArgumentPack;
4416 llvm::PointerUnion<Decl *, DeclArgumentPack *> *Found
4417 = CurrentInstantiationScope->findInstantiationOf(D);
4420 if (Decl *FD = Found->dyn_cast<Decl *>())
4421 return cast<NamedDecl>(FD);
4423 int PackIdx = ArgumentPackSubstitutionIndex;
4424 assert(PackIdx != -1 && "found declaration pack but not pack expanding");
4425 return cast<NamedDecl>((*Found->get<DeclArgumentPack *>())[PackIdx]);
4428 // If we're performing a partial substitution during template argument
4429 // deduction, we may not have values for template parameters yet. They
4430 // just map to themselves.
4431 if (isa<NonTypeTemplateParmDecl>(D) || isa<TemplateTypeParmDecl>(D) ||
4432 isa<TemplateTemplateParmDecl>(D))
4435 if (D->isInvalidDecl())
4438 // If we didn't find the decl, then we must have a label decl that hasn't
4439 // been found yet. Lazily instantiate it and return it now.
4440 assert(isa<LabelDecl>(D));
4442 Decl *Inst = SubstDecl(D, CurContext, TemplateArgs);
4443 assert(Inst && "Failed to instantiate label??");
4445 CurrentInstantiationScope->InstantiatedLocal(D, Inst);
4446 return cast<LabelDecl>(Inst);
4449 // For variable template specializations, update those that are still
4451 if (VarTemplateSpecializationDecl *VarSpec =
4452 dyn_cast<VarTemplateSpecializationDecl>(D)) {
4453 bool InstantiationDependent = false;
4454 const TemplateArgumentListInfo &VarTemplateArgs =
4455 VarSpec->getTemplateArgsInfo();
4456 if (TemplateSpecializationType::anyDependentTemplateArguments(
4457 VarTemplateArgs, InstantiationDependent))
4458 D = cast<NamedDecl>(
4459 SubstDecl(D, VarSpec->getDeclContext(), TemplateArgs));
4463 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(D)) {
4464 if (!Record->isDependentContext())
4467 // Determine whether this record is the "templated" declaration describing
4468 // a class template or class template partial specialization.
4469 ClassTemplateDecl *ClassTemplate = Record->getDescribedClassTemplate();
4471 ClassTemplate = ClassTemplate->getCanonicalDecl();
4472 else if (ClassTemplatePartialSpecializationDecl *PartialSpec
4473 = dyn_cast<ClassTemplatePartialSpecializationDecl>(Record))
4474 ClassTemplate = PartialSpec->getSpecializedTemplate()->getCanonicalDecl();
4476 // Walk the current context to find either the record or an instantiation of
4478 DeclContext *DC = CurContext;
4479 while (!DC->isFileContext()) {
4480 // If we're performing substitution while we're inside the template
4481 // definition, we'll find our own context. We're done.
4482 if (DC->Equals(Record))
4485 if (CXXRecordDecl *InstRecord = dyn_cast<CXXRecordDecl>(DC)) {
4486 // Check whether we're in the process of instantiating a class template
4487 // specialization of the template we're mapping.
4488 if (ClassTemplateSpecializationDecl *InstSpec
4489 = dyn_cast<ClassTemplateSpecializationDecl>(InstRecord)){
4490 ClassTemplateDecl *SpecTemplate = InstSpec->getSpecializedTemplate();
4491 if (ClassTemplate && isInstantiationOf(ClassTemplate, SpecTemplate))
4495 // Check whether we're in the process of instantiating a member class.
4496 if (isInstantiationOf(Record, InstRecord))
4500 // Move to the outer template scope.
4501 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(DC)) {
4502 if (FD->getFriendObjectKind() && FD->getDeclContext()->isFileContext()){
4503 DC = FD->getLexicalDeclContext();
4508 DC = DC->getParent();
4511 // Fall through to deal with other dependent record types (e.g.,
4512 // anonymous unions in class templates).
4515 if (!ParentDC->isDependentContext())
4518 ParentDC = FindInstantiatedContext(Loc, ParentDC, TemplateArgs);
4522 if (ParentDC != D->getDeclContext()) {
4523 // We performed some kind of instantiation in the parent context,
4524 // so now we need to look into the instantiated parent context to
4525 // find the instantiation of the declaration D.
4527 // If our context used to be dependent, we may need to instantiate
4528 // it before performing lookup into that context.
4529 bool IsBeingInstantiated = false;
4530 if (CXXRecordDecl *Spec = dyn_cast<CXXRecordDecl>(ParentDC)) {
4531 if (!Spec->isDependentContext()) {
4532 QualType T = Context.getTypeDeclType(Spec);
4533 const RecordType *Tag = T->getAs<RecordType>();
4534 assert(Tag && "type of non-dependent record is not a RecordType");
4535 if (Tag->isBeingDefined())
4536 IsBeingInstantiated = true;
4537 if (!Tag->isBeingDefined() &&
4538 RequireCompleteType(Loc, T, diag::err_incomplete_type))
4541 ParentDC = Tag->getDecl();
4545 NamedDecl *Result = nullptr;
4546 if (D->getDeclName()) {
4547 DeclContext::lookup_result Found = ParentDC->lookup(D->getDeclName());
4548 Result = findInstantiationOf(Context, D, Found.begin(), Found.end());
4550 // Since we don't have a name for the entity we're looking for,
4551 // our only option is to walk through all of the declarations to
4552 // find that name. This will occur in a few cases:
4554 // - anonymous struct/union within a template
4555 // - unnamed class/struct/union/enum within a template
4557 // FIXME: Find a better way to find these instantiations!
4558 Result = findInstantiationOf(Context, D,
4559 ParentDC->decls_begin(),
4560 ParentDC->decls_end());
4564 if (isa<UsingShadowDecl>(D)) {
4565 // UsingShadowDecls can instantiate to nothing because of using hiding.
4566 } else if (Diags.hasErrorOccurred()) {
4567 // We've already complained about something, so most likely this
4568 // declaration failed to instantiate. There's no point in complaining
4569 // further, since this is normal in invalid code.
4570 } else if (IsBeingInstantiated) {
4571 // The class in which this member exists is currently being
4572 // instantiated, and we haven't gotten around to instantiating this
4573 // member yet. This can happen when the code uses forward declarations
4574 // of member classes, and introduces ordering dependencies via
4575 // template instantiation.
4576 Diag(Loc, diag::err_member_not_yet_instantiated)
4578 << Context.getTypeDeclType(cast<CXXRecordDecl>(ParentDC));
4579 Diag(D->getLocation(), diag::note_non_instantiated_member_here);
4580 } else if (EnumConstantDecl *ED = dyn_cast<EnumConstantDecl>(D)) {
4581 // This enumeration constant was found when the template was defined,
4582 // but can't be found in the instantiation. This can happen if an
4583 // unscoped enumeration member is explicitly specialized.
4584 EnumDecl *Enum = cast<EnumDecl>(ED->getLexicalDeclContext());
4585 EnumDecl *Spec = cast<EnumDecl>(FindInstantiatedDecl(Loc, Enum,
4587 assert(Spec->getTemplateSpecializationKind() ==
4588 TSK_ExplicitSpecialization);
4589 Diag(Loc, diag::err_enumerator_does_not_exist)
4591 << Context.getTypeDeclType(cast<TypeDecl>(Spec->getDeclContext()));
4592 Diag(Spec->getLocation(), diag::note_enum_specialized_here)
4593 << Context.getTypeDeclType(Spec);
4595 // We should have found something, but didn't.
4596 llvm_unreachable("Unable to find instantiation of declaration!");
4606 /// \brief Performs template instantiation for all implicit template
4607 /// instantiations we have seen until this point.
4608 void Sema::PerformPendingInstantiations(bool LocalOnly) {
4609 while (!PendingLocalImplicitInstantiations.empty() ||
4610 (!LocalOnly && !PendingInstantiations.empty())) {
4611 PendingImplicitInstantiation Inst;
4613 if (PendingLocalImplicitInstantiations.empty()) {
4614 Inst = PendingInstantiations.front();
4615 PendingInstantiations.pop_front();
4617 Inst = PendingLocalImplicitInstantiations.front();
4618 PendingLocalImplicitInstantiations.pop_front();
4621 // Instantiate function definitions
4622 if (FunctionDecl *Function = dyn_cast<FunctionDecl>(Inst.first)) {
4623 PrettyDeclStackTraceEntry CrashInfo(*this, Function, SourceLocation(),
4624 "instantiating function definition");
4625 bool DefinitionRequired = Function->getTemplateSpecializationKind() ==
4626 TSK_ExplicitInstantiationDefinition;
4627 InstantiateFunctionDefinition(/*FIXME:*/Inst.second, Function, true,
4628 DefinitionRequired);
4632 // Instantiate variable definitions
4633 VarDecl *Var = cast<VarDecl>(Inst.first);
4635 assert((Var->isStaticDataMember() ||
4636 isa<VarTemplateSpecializationDecl>(Var)) &&
4637 "Not a static data member, nor a variable template"
4638 " specialization?");
4640 // Don't try to instantiate declarations if the most recent redeclaration
4642 if (Var->getMostRecentDecl()->isInvalidDecl())
4645 // Check if the most recent declaration has changed the specialization kind
4646 // and removed the need for implicit instantiation.
4647 switch (Var->getMostRecentDecl()->getTemplateSpecializationKind()) {
4648 case TSK_Undeclared:
4649 llvm_unreachable("Cannot instantitiate an undeclared specialization.");
4650 case TSK_ExplicitInstantiationDeclaration:
4651 case TSK_ExplicitSpecialization:
4652 continue; // No longer need to instantiate this type.
4653 case TSK_ExplicitInstantiationDefinition:
4654 // We only need an instantiation if the pending instantiation *is* the
4655 // explicit instantiation.
4656 if (Var != Var->getMostRecentDecl()) continue;
4657 case TSK_ImplicitInstantiation:
4661 PrettyDeclStackTraceEntry CrashInfo(*this, Var, SourceLocation(),
4662 "instantiating variable definition");
4663 bool DefinitionRequired = Var->getTemplateSpecializationKind() ==
4664 TSK_ExplicitInstantiationDefinition;
4666 // Instantiate static data member definitions or variable template
4668 InstantiateVariableDefinition(/*FIXME:*/ Inst.second, Var, true,
4669 DefinitionRequired);
4673 void Sema::PerformDependentDiagnostics(const DeclContext *Pattern,
4674 const MultiLevelTemplateArgumentList &TemplateArgs) {
4675 for (auto DD : Pattern->ddiags()) {
4676 switch (DD->getKind()) {
4677 case DependentDiagnostic::Access:
4678 HandleDependentAccessCheck(*DD, TemplateArgs);