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 template<typename DeclT>
40 static bool SubstQualifier(Sema &SemaRef, const DeclT *OldDecl, DeclT *NewDecl,
41 const MultiLevelTemplateArgumentList &TemplateArgs) {
42 if (!OldDecl->getQualifierLoc())
45 assert((NewDecl->getFriendObjectKind() ||
46 !OldDecl->getLexicalDeclContext()->isDependentContext()) &&
47 "non-friend with qualified name defined in dependent context");
48 Sema::ContextRAII SavedContext(
50 const_cast<DeclContext *>(NewDecl->getFriendObjectKind()
51 ? NewDecl->getLexicalDeclContext()
52 : OldDecl->getLexicalDeclContext()));
54 NestedNameSpecifierLoc NewQualifierLoc
55 = SemaRef.SubstNestedNameSpecifierLoc(OldDecl->getQualifierLoc(),
61 NewDecl->setQualifierInfo(NewQualifierLoc);
65 bool TemplateDeclInstantiator::SubstQualifier(const DeclaratorDecl *OldDecl,
66 DeclaratorDecl *NewDecl) {
67 return ::SubstQualifier(SemaRef, OldDecl, NewDecl, TemplateArgs);
70 bool TemplateDeclInstantiator::SubstQualifier(const TagDecl *OldDecl,
72 return ::SubstQualifier(SemaRef, OldDecl, NewDecl, TemplateArgs);
75 // Include attribute instantiation code.
76 #include "clang/Sema/AttrTemplateInstantiate.inc"
78 static void instantiateDependentAlignedAttr(
79 Sema &S, const MultiLevelTemplateArgumentList &TemplateArgs,
80 const AlignedAttr *Aligned, Decl *New, bool IsPackExpansion) {
81 if (Aligned->isAlignmentExpr()) {
82 // The alignment expression is a constant expression.
83 EnterExpressionEvaluationContext Unevaluated(S, Sema::ConstantEvaluated);
84 ExprResult Result = S.SubstExpr(Aligned->getAlignmentExpr(), TemplateArgs);
85 if (!Result.isInvalid())
86 S.AddAlignedAttr(Aligned->getLocation(), New, Result.getAs<Expr>(),
87 Aligned->getSpellingListIndex(), IsPackExpansion);
89 TypeSourceInfo *Result = S.SubstType(Aligned->getAlignmentType(),
90 TemplateArgs, Aligned->getLocation(),
93 S.AddAlignedAttr(Aligned->getLocation(), New, Result,
94 Aligned->getSpellingListIndex(), IsPackExpansion);
98 static void instantiateDependentAlignedAttr(
99 Sema &S, const MultiLevelTemplateArgumentList &TemplateArgs,
100 const AlignedAttr *Aligned, Decl *New) {
101 if (!Aligned->isPackExpansion()) {
102 instantiateDependentAlignedAttr(S, TemplateArgs, Aligned, New, false);
106 SmallVector<UnexpandedParameterPack, 2> Unexpanded;
107 if (Aligned->isAlignmentExpr())
108 S.collectUnexpandedParameterPacks(Aligned->getAlignmentExpr(),
111 S.collectUnexpandedParameterPacks(Aligned->getAlignmentType()->getTypeLoc(),
113 assert(!Unexpanded.empty() && "Pack expansion without parameter packs?");
115 // Determine whether we can expand this attribute pack yet.
116 bool Expand = true, RetainExpansion = false;
117 Optional<unsigned> NumExpansions;
118 // FIXME: Use the actual location of the ellipsis.
119 SourceLocation EllipsisLoc = Aligned->getLocation();
120 if (S.CheckParameterPacksForExpansion(EllipsisLoc, Aligned->getRange(),
121 Unexpanded, TemplateArgs, Expand,
122 RetainExpansion, NumExpansions))
126 Sema::ArgumentPackSubstitutionIndexRAII SubstIndex(S, -1);
127 instantiateDependentAlignedAttr(S, TemplateArgs, Aligned, New, true);
129 for (unsigned I = 0; I != *NumExpansions; ++I) {
130 Sema::ArgumentPackSubstitutionIndexRAII SubstIndex(S, I);
131 instantiateDependentAlignedAttr(S, TemplateArgs, Aligned, New, false);
136 static void instantiateDependentAssumeAlignedAttr(
137 Sema &S, const MultiLevelTemplateArgumentList &TemplateArgs,
138 const AssumeAlignedAttr *Aligned, Decl *New) {
139 // The alignment expression is a constant expression.
140 EnterExpressionEvaluationContext Unevaluated(S, Sema::ConstantEvaluated);
142 Expr *E, *OE = nullptr;
143 ExprResult Result = S.SubstExpr(Aligned->getAlignment(), TemplateArgs);
144 if (Result.isInvalid())
146 E = Result.getAs<Expr>();
148 if (Aligned->getOffset()) {
149 Result = S.SubstExpr(Aligned->getOffset(), TemplateArgs);
150 if (Result.isInvalid())
152 OE = Result.getAs<Expr>();
155 S.AddAssumeAlignedAttr(Aligned->getLocation(), New, E, OE,
156 Aligned->getSpellingListIndex());
159 static void instantiateDependentAlignValueAttr(
160 Sema &S, const MultiLevelTemplateArgumentList &TemplateArgs,
161 const AlignValueAttr *Aligned, Decl *New) {
162 // The alignment expression is a constant expression.
163 EnterExpressionEvaluationContext Unevaluated(S, Sema::ConstantEvaluated);
164 ExprResult Result = S.SubstExpr(Aligned->getAlignment(), TemplateArgs);
165 if (!Result.isInvalid())
166 S.AddAlignValueAttr(Aligned->getLocation(), New, Result.getAs<Expr>(),
167 Aligned->getSpellingListIndex());
170 static void instantiateDependentEnableIfAttr(
171 Sema &S, const MultiLevelTemplateArgumentList &TemplateArgs,
172 const EnableIfAttr *A, const Decl *Tmpl, Decl *New) {
173 Expr *Cond = nullptr;
175 EnterExpressionEvaluationContext Unevaluated(S, Sema::Unevaluated);
176 ExprResult Result = S.SubstExpr(A->getCond(), TemplateArgs);
177 if (Result.isInvalid())
179 Cond = Result.getAs<Expr>();
181 if (A->getCond()->isTypeDependent() && !Cond->isTypeDependent()) {
182 ExprResult Converted = S.PerformContextuallyConvertToBool(Cond);
183 if (Converted.isInvalid())
185 Cond = Converted.get();
188 SmallVector<PartialDiagnosticAt, 8> Diags;
189 if (A->getCond()->isValueDependent() && !Cond->isValueDependent() &&
190 !Expr::isPotentialConstantExprUnevaluated(Cond, cast<FunctionDecl>(Tmpl),
192 S.Diag(A->getLocation(), diag::err_enable_if_never_constant_expr);
193 for (int I = 0, N = Diags.size(); I != N; ++I)
194 S.Diag(Diags[I].first, Diags[I].second);
198 EnableIfAttr *EIA = new (S.getASTContext())
199 EnableIfAttr(A->getLocation(), S.getASTContext(), Cond,
201 A->getSpellingListIndex());
205 // Constructs and adds to New a new instance of CUDALaunchBoundsAttr using
206 // template A as the base and arguments from TemplateArgs.
207 static void instantiateDependentCUDALaunchBoundsAttr(
208 Sema &S, const MultiLevelTemplateArgumentList &TemplateArgs,
209 const CUDALaunchBoundsAttr &Attr, Decl *New) {
210 // The alignment expression is a constant expression.
211 EnterExpressionEvaluationContext Unevaluated(S, Sema::ConstantEvaluated);
213 ExprResult Result = S.SubstExpr(Attr.getMaxThreads(), TemplateArgs);
214 if (Result.isInvalid())
216 Expr *MaxThreads = Result.getAs<Expr>();
218 Expr *MinBlocks = nullptr;
219 if (Attr.getMinBlocks()) {
220 Result = S.SubstExpr(Attr.getMinBlocks(), TemplateArgs);
221 if (Result.isInvalid())
223 MinBlocks = Result.getAs<Expr>();
226 S.AddLaunchBoundsAttr(Attr.getLocation(), New, MaxThreads, MinBlocks,
227 Attr.getSpellingListIndex());
230 void Sema::InstantiateAttrs(const MultiLevelTemplateArgumentList &TemplateArgs,
231 const Decl *Tmpl, Decl *New,
232 LateInstantiatedAttrVec *LateAttrs,
233 LocalInstantiationScope *OuterMostScope) {
234 for (const auto *TmplAttr : Tmpl->attrs()) {
235 // FIXME: This should be generalized to more than just the AlignedAttr.
236 const AlignedAttr *Aligned = dyn_cast<AlignedAttr>(TmplAttr);
237 if (Aligned && Aligned->isAlignmentDependent()) {
238 instantiateDependentAlignedAttr(*this, TemplateArgs, Aligned, New);
242 const AssumeAlignedAttr *AssumeAligned = dyn_cast<AssumeAlignedAttr>(TmplAttr);
244 instantiateDependentAssumeAlignedAttr(*this, TemplateArgs, AssumeAligned, New);
248 const AlignValueAttr *AlignValue = dyn_cast<AlignValueAttr>(TmplAttr);
250 instantiateDependentAlignValueAttr(*this, TemplateArgs, AlignValue, New);
254 const EnableIfAttr *EnableIf = dyn_cast<EnableIfAttr>(TmplAttr);
255 if (EnableIf && EnableIf->getCond()->isValueDependent()) {
256 instantiateDependentEnableIfAttr(*this, TemplateArgs, EnableIf, Tmpl,
261 if (const CUDALaunchBoundsAttr *CUDALaunchBounds =
262 dyn_cast<CUDALaunchBoundsAttr>(TmplAttr)) {
263 instantiateDependentCUDALaunchBoundsAttr(*this, TemplateArgs,
264 *CUDALaunchBounds, New);
268 // Existing DLL attribute on the instantiation takes precedence.
269 if (TmplAttr->getKind() == attr::DLLExport ||
270 TmplAttr->getKind() == attr::DLLImport) {
271 if (New->hasAttr<DLLExportAttr>() || New->hasAttr<DLLImportAttr>()) {
276 assert(!TmplAttr->isPackExpansion());
277 if (TmplAttr->isLateParsed() && LateAttrs) {
278 // Late parsed attributes must be instantiated and attached after the
279 // enclosing class has been instantiated. See Sema::InstantiateClass.
280 LocalInstantiationScope *Saved = nullptr;
281 if (CurrentInstantiationScope)
282 Saved = CurrentInstantiationScope->cloneScopes(OuterMostScope);
283 LateAttrs->push_back(LateInstantiatedAttribute(TmplAttr, Saved, New));
285 // Allow 'this' within late-parsed attributes.
286 NamedDecl *ND = dyn_cast<NamedDecl>(New);
287 CXXRecordDecl *ThisContext =
288 dyn_cast_or_null<CXXRecordDecl>(ND->getDeclContext());
289 CXXThisScopeRAII ThisScope(*this, ThisContext, /*TypeQuals*/0,
290 ND && ND->isCXXInstanceMember());
292 Attr *NewAttr = sema::instantiateTemplateAttribute(TmplAttr, Context,
293 *this, TemplateArgs);
295 New->addAttr(NewAttr);
300 /// Get the previous declaration of a declaration for the purposes of template
301 /// instantiation. If this finds a previous declaration, then the previous
302 /// declaration of the instantiation of D should be an instantiation of the
303 /// result of this function.
304 template<typename DeclT>
305 static DeclT *getPreviousDeclForInstantiation(DeclT *D) {
306 DeclT *Result = D->getPreviousDecl();
308 // If the declaration is within a class, and the previous declaration was
309 // merged from a different definition of that class, then we don't have a
310 // previous declaration for the purpose of template instantiation.
311 if (Result && isa<CXXRecordDecl>(D->getDeclContext()) &&
312 D->getLexicalDeclContext() != Result->getLexicalDeclContext())
319 TemplateDeclInstantiator::VisitTranslationUnitDecl(TranslationUnitDecl *D) {
320 llvm_unreachable("Translation units cannot be instantiated");
324 TemplateDeclInstantiator::VisitExternCContextDecl(ExternCContextDecl *D) {
325 llvm_unreachable("extern \"C\" context cannot be instantiated");
329 TemplateDeclInstantiator::VisitLabelDecl(LabelDecl *D) {
330 LabelDecl *Inst = LabelDecl::Create(SemaRef.Context, Owner, D->getLocation(),
332 Owner->addDecl(Inst);
337 TemplateDeclInstantiator::VisitNamespaceDecl(NamespaceDecl *D) {
338 llvm_unreachable("Namespaces cannot be instantiated");
342 TemplateDeclInstantiator::VisitNamespaceAliasDecl(NamespaceAliasDecl *D) {
343 NamespaceAliasDecl *Inst
344 = NamespaceAliasDecl::Create(SemaRef.Context, Owner,
345 D->getNamespaceLoc(),
348 D->getQualifierLoc(),
349 D->getTargetNameLoc(),
351 Owner->addDecl(Inst);
355 Decl *TemplateDeclInstantiator::InstantiateTypedefNameDecl(TypedefNameDecl *D,
357 bool Invalid = false;
358 TypeSourceInfo *DI = D->getTypeSourceInfo();
359 if (DI->getType()->isInstantiationDependentType() ||
360 DI->getType()->isVariablyModifiedType()) {
361 DI = SemaRef.SubstType(DI, TemplateArgs,
362 D->getLocation(), D->getDeclName());
365 DI = SemaRef.Context.getTrivialTypeSourceInfo(SemaRef.Context.IntTy);
368 SemaRef.MarkDeclarationsReferencedInType(D->getLocation(), DI->getType());
371 // HACK: g++ has a bug where it gets the value kind of ?: wrong.
372 // libstdc++ relies upon this bug in its implementation of common_type.
373 // If we happen to be processing that implementation, fake up the g++ ?:
374 // semantics. See LWG issue 2141 for more information on the bug.
375 const DecltypeType *DT = DI->getType()->getAs<DecltypeType>();
376 CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(D->getDeclContext());
377 if (DT && RD && isa<ConditionalOperator>(DT->getUnderlyingExpr()) &&
378 DT->isReferenceType() &&
379 RD->getEnclosingNamespaceContext() == SemaRef.getStdNamespace() &&
380 RD->getIdentifier() && RD->getIdentifier()->isStr("common_type") &&
381 D->getIdentifier() && D->getIdentifier()->isStr("type") &&
382 SemaRef.getSourceManager().isInSystemHeader(D->getLocStart()))
383 // Fold it to the (non-reference) type which g++ would have produced.
384 DI = SemaRef.Context.getTrivialTypeSourceInfo(
385 DI->getType().getNonReferenceType());
387 // Create the new typedef
388 TypedefNameDecl *Typedef;
390 Typedef = TypeAliasDecl::Create(SemaRef.Context, Owner, D->getLocStart(),
391 D->getLocation(), D->getIdentifier(), DI);
393 Typedef = TypedefDecl::Create(SemaRef.Context, Owner, D->getLocStart(),
394 D->getLocation(), D->getIdentifier(), DI);
396 Typedef->setInvalidDecl();
398 // If the old typedef was the name for linkage purposes of an anonymous
399 // tag decl, re-establish that relationship for the new typedef.
400 if (const TagType *oldTagType = D->getUnderlyingType()->getAs<TagType>()) {
401 TagDecl *oldTag = oldTagType->getDecl();
402 if (oldTag->getTypedefNameForAnonDecl() == D && !Invalid) {
403 TagDecl *newTag = DI->getType()->castAs<TagType>()->getDecl();
404 assert(!newTag->hasNameForLinkage());
405 newTag->setTypedefNameForAnonDecl(Typedef);
409 if (TypedefNameDecl *Prev = getPreviousDeclForInstantiation(D)) {
410 NamedDecl *InstPrev = SemaRef.FindInstantiatedDecl(D->getLocation(), Prev,
415 TypedefNameDecl *InstPrevTypedef = cast<TypedefNameDecl>(InstPrev);
417 // If the typedef types are not identical, reject them.
418 SemaRef.isIncompatibleTypedef(InstPrevTypedef, Typedef);
420 Typedef->setPreviousDecl(InstPrevTypedef);
423 SemaRef.InstantiateAttrs(TemplateArgs, D, Typedef);
425 Typedef->setAccess(D->getAccess());
430 Decl *TemplateDeclInstantiator::VisitTypedefDecl(TypedefDecl *D) {
431 Decl *Typedef = InstantiateTypedefNameDecl(D, /*IsTypeAlias=*/false);
433 Owner->addDecl(Typedef);
437 Decl *TemplateDeclInstantiator::VisitTypeAliasDecl(TypeAliasDecl *D) {
438 Decl *Typedef = InstantiateTypedefNameDecl(D, /*IsTypeAlias=*/true);
440 Owner->addDecl(Typedef);
445 TemplateDeclInstantiator::VisitTypeAliasTemplateDecl(TypeAliasTemplateDecl *D) {
446 // Create a local instantiation scope for this type alias template, which
447 // will contain the instantiations of the template parameters.
448 LocalInstantiationScope Scope(SemaRef);
450 TemplateParameterList *TempParams = D->getTemplateParameters();
451 TemplateParameterList *InstParams = SubstTemplateParams(TempParams);
455 TypeAliasDecl *Pattern = D->getTemplatedDecl();
457 TypeAliasTemplateDecl *PrevAliasTemplate = nullptr;
458 if (getPreviousDeclForInstantiation<TypedefNameDecl>(Pattern)) {
459 DeclContext::lookup_result Found = Owner->lookup(Pattern->getDeclName());
460 if (!Found.empty()) {
461 PrevAliasTemplate = dyn_cast<TypeAliasTemplateDecl>(Found.front());
465 TypeAliasDecl *AliasInst = cast_or_null<TypeAliasDecl>(
466 InstantiateTypedefNameDecl(Pattern, /*IsTypeAlias=*/true));
470 TypeAliasTemplateDecl *Inst
471 = TypeAliasTemplateDecl::Create(SemaRef.Context, Owner, D->getLocation(),
472 D->getDeclName(), InstParams, AliasInst);
473 AliasInst->setDescribedAliasTemplate(Inst);
474 if (PrevAliasTemplate)
475 Inst->setPreviousDecl(PrevAliasTemplate);
477 Inst->setAccess(D->getAccess());
479 if (!PrevAliasTemplate)
480 Inst->setInstantiatedFromMemberTemplate(D);
482 Owner->addDecl(Inst);
487 Decl *TemplateDeclInstantiator::VisitVarDecl(VarDecl *D) {
488 return VisitVarDecl(D, /*InstantiatingVarTemplate=*/false);
491 Decl *TemplateDeclInstantiator::VisitVarDecl(VarDecl *D,
492 bool InstantiatingVarTemplate) {
494 // If this is the variable for an anonymous struct or union,
495 // instantiate the anonymous struct/union type first.
496 if (const RecordType *RecordTy = D->getType()->getAs<RecordType>())
497 if (RecordTy->getDecl()->isAnonymousStructOrUnion())
498 if (!VisitCXXRecordDecl(cast<CXXRecordDecl>(RecordTy->getDecl())))
501 // Do substitution on the type of the declaration
502 TypeSourceInfo *DI = SemaRef.SubstType(D->getTypeSourceInfo(),
504 D->getTypeSpecStartLoc(),
509 if (DI->getType()->isFunctionType()) {
510 SemaRef.Diag(D->getLocation(), diag::err_variable_instantiates_to_function)
511 << D->isStaticDataMember() << DI->getType();
515 DeclContext *DC = Owner;
516 if (D->isLocalExternDecl())
517 SemaRef.adjustContextForLocalExternDecl(DC);
519 // Build the instantiated declaration.
520 VarDecl *Var = VarDecl::Create(SemaRef.Context, DC, D->getInnerLocStart(),
521 D->getLocation(), D->getIdentifier(),
522 DI->getType(), DI, D->getStorageClass());
524 // In ARC, infer 'retaining' for variables of retainable type.
525 if (SemaRef.getLangOpts().ObjCAutoRefCount &&
526 SemaRef.inferObjCARCLifetime(Var))
527 Var->setInvalidDecl();
529 // Substitute the nested name specifier, if any.
530 if (SubstQualifier(D, Var))
533 SemaRef.BuildVariableInstantiation(Var, D, TemplateArgs, LateAttrs, Owner,
534 StartingScope, InstantiatingVarTemplate);
536 if (D->isNRVOVariable()) {
537 QualType ReturnType = cast<FunctionDecl>(DC)->getReturnType();
538 if (SemaRef.isCopyElisionCandidate(ReturnType, Var, false))
539 Var->setNRVOVariable(true);
542 Var->setImplicit(D->isImplicit());
547 Decl *TemplateDeclInstantiator::VisitAccessSpecDecl(AccessSpecDecl *D) {
549 = AccessSpecDecl::Create(SemaRef.Context, D->getAccess(), Owner,
550 D->getAccessSpecifierLoc(), D->getColonLoc());
551 Owner->addHiddenDecl(AD);
555 Decl *TemplateDeclInstantiator::VisitFieldDecl(FieldDecl *D) {
556 bool Invalid = false;
557 TypeSourceInfo *DI = D->getTypeSourceInfo();
558 if (DI->getType()->isInstantiationDependentType() ||
559 DI->getType()->isVariablyModifiedType()) {
560 DI = SemaRef.SubstType(DI, TemplateArgs,
561 D->getLocation(), D->getDeclName());
563 DI = D->getTypeSourceInfo();
565 } else if (DI->getType()->isFunctionType()) {
566 // C++ [temp.arg.type]p3:
567 // If a declaration acquires a function type through a type
568 // dependent on a template-parameter and this causes a
569 // declaration that does not use the syntactic form of a
570 // function declarator to have function type, the program is
572 SemaRef.Diag(D->getLocation(), diag::err_field_instantiates_to_function)
577 SemaRef.MarkDeclarationsReferencedInType(D->getLocation(), DI->getType());
580 Expr *BitWidth = D->getBitWidth();
584 // The bit-width expression is a constant expression.
585 EnterExpressionEvaluationContext Unevaluated(SemaRef,
586 Sema::ConstantEvaluated);
588 ExprResult InstantiatedBitWidth
589 = SemaRef.SubstExpr(BitWidth, TemplateArgs);
590 if (InstantiatedBitWidth.isInvalid()) {
594 BitWidth = InstantiatedBitWidth.getAs<Expr>();
597 FieldDecl *Field = SemaRef.CheckFieldDecl(D->getDeclName(),
599 cast<RecordDecl>(Owner),
603 D->getInClassInitStyle(),
604 D->getInnerLocStart(),
608 cast<Decl>(Owner)->setInvalidDecl();
612 SemaRef.InstantiateAttrs(TemplateArgs, D, Field, LateAttrs, StartingScope);
614 if (Field->hasAttrs())
615 SemaRef.CheckAlignasUnderalignment(Field);
618 Field->setInvalidDecl();
620 if (!Field->getDeclName()) {
621 // Keep track of where this decl came from.
622 SemaRef.Context.setInstantiatedFromUnnamedFieldDecl(Field, D);
624 if (CXXRecordDecl *Parent= dyn_cast<CXXRecordDecl>(Field->getDeclContext())) {
625 if (Parent->isAnonymousStructOrUnion() &&
626 Parent->getRedeclContext()->isFunctionOrMethod())
627 SemaRef.CurrentInstantiationScope->InstantiatedLocal(D, Field);
630 Field->setImplicit(D->isImplicit());
631 Field->setAccess(D->getAccess());
632 Owner->addDecl(Field);
637 Decl *TemplateDeclInstantiator::VisitMSPropertyDecl(MSPropertyDecl *D) {
638 bool Invalid = false;
639 TypeSourceInfo *DI = D->getTypeSourceInfo();
641 if (DI->getType()->isVariablyModifiedType()) {
642 SemaRef.Diag(D->getLocation(), diag::err_property_is_variably_modified)
645 } else if (DI->getType()->isInstantiationDependentType()) {
646 DI = SemaRef.SubstType(DI, TemplateArgs,
647 D->getLocation(), D->getDeclName());
649 DI = D->getTypeSourceInfo();
651 } else if (DI->getType()->isFunctionType()) {
652 // C++ [temp.arg.type]p3:
653 // If a declaration acquires a function type through a type
654 // dependent on a template-parameter and this causes a
655 // declaration that does not use the syntactic form of a
656 // function declarator to have function type, the program is
658 SemaRef.Diag(D->getLocation(), diag::err_field_instantiates_to_function)
663 SemaRef.MarkDeclarationsReferencedInType(D->getLocation(), DI->getType());
666 MSPropertyDecl *Property = MSPropertyDecl::Create(
667 SemaRef.Context, Owner, D->getLocation(), D->getDeclName(), DI->getType(),
668 DI, D->getLocStart(), D->getGetterId(), D->getSetterId());
670 SemaRef.InstantiateAttrs(TemplateArgs, D, Property, LateAttrs,
674 Property->setInvalidDecl();
676 Property->setAccess(D->getAccess());
677 Owner->addDecl(Property);
682 Decl *TemplateDeclInstantiator::VisitIndirectFieldDecl(IndirectFieldDecl *D) {
683 NamedDecl **NamedChain =
684 new (SemaRef.Context)NamedDecl*[D->getChainingSize()];
687 for (auto *PI : D->chain()) {
688 NamedDecl *Next = SemaRef.FindInstantiatedDecl(D->getLocation(), PI,
693 NamedChain[i++] = Next;
696 QualType T = cast<FieldDecl>(NamedChain[i-1])->getType();
697 IndirectFieldDecl *IndirectField = IndirectFieldDecl::Create(
698 SemaRef.Context, Owner, D->getLocation(), D->getIdentifier(), T,
699 NamedChain, D->getChainingSize());
701 for (const auto *Attr : D->attrs())
702 IndirectField->addAttr(Attr->clone(SemaRef.Context));
704 IndirectField->setImplicit(D->isImplicit());
705 IndirectField->setAccess(D->getAccess());
706 Owner->addDecl(IndirectField);
707 return IndirectField;
710 Decl *TemplateDeclInstantiator::VisitFriendDecl(FriendDecl *D) {
711 // Handle friend type expressions by simply substituting template
712 // parameters into the pattern type and checking the result.
713 if (TypeSourceInfo *Ty = D->getFriendType()) {
714 TypeSourceInfo *InstTy;
715 // If this is an unsupported friend, don't bother substituting template
716 // arguments into it. The actual type referred to won't be used by any
717 // parts of Clang, and may not be valid for instantiating. Just use the
718 // same info for the instantiated friend.
719 if (D->isUnsupportedFriend()) {
722 InstTy = SemaRef.SubstType(Ty, TemplateArgs,
723 D->getLocation(), DeclarationName());
728 FriendDecl *FD = SemaRef.CheckFriendTypeDecl(D->getLocStart(),
729 D->getFriendLoc(), InstTy);
733 FD->setAccess(AS_public);
734 FD->setUnsupportedFriend(D->isUnsupportedFriend());
739 NamedDecl *ND = D->getFriendDecl();
740 assert(ND && "friend decl must be a decl or a type!");
742 // All of the Visit implementations for the various potential friend
743 // declarations have to be carefully written to work for friend
744 // objects, with the most important detail being that the target
745 // decl should almost certainly not be placed in Owner.
746 Decl *NewND = Visit(ND);
747 if (!NewND) return nullptr;
750 FriendDecl::Create(SemaRef.Context, Owner, D->getLocation(),
751 cast<NamedDecl>(NewND), D->getFriendLoc());
752 FD->setAccess(AS_public);
753 FD->setUnsupportedFriend(D->isUnsupportedFriend());
758 Decl *TemplateDeclInstantiator::VisitStaticAssertDecl(StaticAssertDecl *D) {
759 Expr *AssertExpr = D->getAssertExpr();
761 // The expression in a static assertion is a constant expression.
762 EnterExpressionEvaluationContext Unevaluated(SemaRef,
763 Sema::ConstantEvaluated);
765 ExprResult InstantiatedAssertExpr
766 = SemaRef.SubstExpr(AssertExpr, TemplateArgs);
767 if (InstantiatedAssertExpr.isInvalid())
770 return SemaRef.BuildStaticAssertDeclaration(D->getLocation(),
771 InstantiatedAssertExpr.get(),
777 Decl *TemplateDeclInstantiator::VisitEnumDecl(EnumDecl *D) {
778 EnumDecl *PrevDecl = nullptr;
779 if (EnumDecl *PatternPrev = getPreviousDeclForInstantiation(D)) {
780 NamedDecl *Prev = SemaRef.FindInstantiatedDecl(D->getLocation(),
783 if (!Prev) return nullptr;
784 PrevDecl = cast<EnumDecl>(Prev);
787 EnumDecl *Enum = EnumDecl::Create(SemaRef.Context, Owner, D->getLocStart(),
788 D->getLocation(), D->getIdentifier(),
789 PrevDecl, D->isScoped(),
790 D->isScopedUsingClassTag(), D->isFixed());
792 if (TypeSourceInfo *TI = D->getIntegerTypeSourceInfo()) {
793 // If we have type source information for the underlying type, it means it
794 // has been explicitly set by the user. Perform substitution on it before
796 SourceLocation UnderlyingLoc = TI->getTypeLoc().getBeginLoc();
797 TypeSourceInfo *NewTI = SemaRef.SubstType(TI, TemplateArgs, UnderlyingLoc,
799 if (!NewTI || SemaRef.CheckEnumUnderlyingType(NewTI))
800 Enum->setIntegerType(SemaRef.Context.IntTy);
802 Enum->setIntegerTypeSourceInfo(NewTI);
804 assert(!D->getIntegerType()->isDependentType()
805 && "Dependent type without type source info");
806 Enum->setIntegerType(D->getIntegerType());
810 SemaRef.InstantiateAttrs(TemplateArgs, D, Enum);
812 Enum->setInstantiationOfMemberEnum(D, TSK_ImplicitInstantiation);
813 Enum->setAccess(D->getAccess());
814 // Forward the mangling number from the template to the instantiated decl.
815 SemaRef.Context.setManglingNumber(Enum, SemaRef.Context.getManglingNumber(D));
816 if (SubstQualifier(D, Enum)) return nullptr;
817 Owner->addDecl(Enum);
819 EnumDecl *Def = D->getDefinition();
820 if (Def && Def != D) {
821 // If this is an out-of-line definition of an enum member template, check
822 // that the underlying types match in the instantiation of both
824 if (TypeSourceInfo *TI = Def->getIntegerTypeSourceInfo()) {
825 SourceLocation UnderlyingLoc = TI->getTypeLoc().getBeginLoc();
826 QualType DefnUnderlying =
827 SemaRef.SubstType(TI->getType(), TemplateArgs,
828 UnderlyingLoc, DeclarationName());
829 SemaRef.CheckEnumRedeclaration(Def->getLocation(), Def->isScoped(),
830 DefnUnderlying, Enum);
834 // C++11 [temp.inst]p1: The implicit instantiation of a class template
835 // specialization causes the implicit instantiation of the declarations, but
836 // not the definitions of scoped member enumerations.
838 // DR1484 clarifies that enumeration definitions inside of a template
839 // declaration aren't considered entities that can be separately instantiated
840 // from the rest of the entity they are declared inside of.
841 if (isDeclWithinFunction(D) ? D == Def : Def && !Enum->isScoped()) {
842 SemaRef.CurrentInstantiationScope->InstantiatedLocal(D, Enum);
843 InstantiateEnumDefinition(Enum, Def);
849 void TemplateDeclInstantiator::InstantiateEnumDefinition(
850 EnumDecl *Enum, EnumDecl *Pattern) {
851 Enum->startDefinition();
853 // Update the location to refer to the definition.
854 Enum->setLocation(Pattern->getLocation());
856 SmallVector<Decl*, 4> Enumerators;
858 EnumConstantDecl *LastEnumConst = nullptr;
859 for (auto *EC : Pattern->enumerators()) {
860 // The specified value for the enumerator.
861 ExprResult Value((Expr *)nullptr);
862 if (Expr *UninstValue = EC->getInitExpr()) {
863 // The enumerator's value expression is a constant expression.
864 EnterExpressionEvaluationContext Unevaluated(SemaRef,
865 Sema::ConstantEvaluated);
867 Value = SemaRef.SubstExpr(UninstValue, TemplateArgs);
870 // Drop the initial value and continue.
871 bool isInvalid = false;
872 if (Value.isInvalid()) {
877 EnumConstantDecl *EnumConst
878 = SemaRef.CheckEnumConstant(Enum, LastEnumConst,
879 EC->getLocation(), EC->getIdentifier(),
884 EnumConst->setInvalidDecl();
885 Enum->setInvalidDecl();
889 SemaRef.InstantiateAttrs(TemplateArgs, EC, EnumConst);
891 EnumConst->setAccess(Enum->getAccess());
892 Enum->addDecl(EnumConst);
893 Enumerators.push_back(EnumConst);
894 LastEnumConst = EnumConst;
896 if (Pattern->getDeclContext()->isFunctionOrMethod() &&
898 // If the enumeration is within a function or method, record the enum
899 // constant as a local.
900 SemaRef.CurrentInstantiationScope->InstantiatedLocal(EC, EnumConst);
905 // FIXME: Fixup LBraceLoc
906 SemaRef.ActOnEnumBody(Enum->getLocation(), SourceLocation(),
907 Enum->getRBraceLoc(), Enum,
912 Decl *TemplateDeclInstantiator::VisitEnumConstantDecl(EnumConstantDecl *D) {
913 llvm_unreachable("EnumConstantDecls can only occur within EnumDecls.");
916 Decl *TemplateDeclInstantiator::VisitClassTemplateDecl(ClassTemplateDecl *D) {
917 bool isFriend = (D->getFriendObjectKind() != Decl::FOK_None);
919 // Create a local instantiation scope for this class template, which
920 // will contain the instantiations of the template parameters.
921 LocalInstantiationScope Scope(SemaRef);
922 TemplateParameterList *TempParams = D->getTemplateParameters();
923 TemplateParameterList *InstParams = SubstTemplateParams(TempParams);
927 CXXRecordDecl *Pattern = D->getTemplatedDecl();
929 // Instantiate the qualifier. We have to do this first in case
930 // we're a friend declaration, because if we are then we need to put
931 // the new declaration in the appropriate context.
932 NestedNameSpecifierLoc QualifierLoc = Pattern->getQualifierLoc();
934 QualifierLoc = SemaRef.SubstNestedNameSpecifierLoc(QualifierLoc,
940 CXXRecordDecl *PrevDecl = nullptr;
941 ClassTemplateDecl *PrevClassTemplate = nullptr;
943 if (!isFriend && getPreviousDeclForInstantiation(Pattern)) {
944 DeclContext::lookup_result Found = Owner->lookup(Pattern->getDeclName());
945 if (!Found.empty()) {
946 PrevClassTemplate = dyn_cast<ClassTemplateDecl>(Found.front());
947 if (PrevClassTemplate)
948 PrevDecl = PrevClassTemplate->getTemplatedDecl();
952 // If this isn't a friend, then it's a member template, in which
953 // case we just want to build the instantiation in the
954 // specialization. If it is a friend, we want to build it in
955 // the appropriate context.
956 DeclContext *DC = Owner;
960 SS.Adopt(QualifierLoc);
961 DC = SemaRef.computeDeclContext(SS);
962 if (!DC) return nullptr;
964 DC = SemaRef.FindInstantiatedContext(Pattern->getLocation(),
965 Pattern->getDeclContext(),
969 // Look for a previous declaration of the template in the owning
971 LookupResult R(SemaRef, Pattern->getDeclName(), Pattern->getLocation(),
972 Sema::LookupOrdinaryName, Sema::ForRedeclaration);
973 SemaRef.LookupQualifiedName(R, DC);
975 if (R.isSingleResult()) {
976 PrevClassTemplate = R.getAsSingle<ClassTemplateDecl>();
977 if (PrevClassTemplate)
978 PrevDecl = PrevClassTemplate->getTemplatedDecl();
981 if (!PrevClassTemplate && QualifierLoc) {
982 SemaRef.Diag(Pattern->getLocation(), diag::err_not_tag_in_scope)
983 << D->getTemplatedDecl()->getTagKind() << Pattern->getDeclName() << DC
984 << QualifierLoc.getSourceRange();
988 bool AdoptedPreviousTemplateParams = false;
989 if (PrevClassTemplate) {
990 bool Complain = true;
992 // HACK: libstdc++ 4.2.1 contains an ill-formed friend class
993 // template for struct std::tr1::__detail::_Map_base, where the
994 // template parameters of the friend declaration don't match the
995 // template parameters of the original declaration. In this one
996 // case, we don't complain about the ill-formed friend
998 if (isFriend && Pattern->getIdentifier() &&
999 Pattern->getIdentifier()->isStr("_Map_base") &&
1000 DC->isNamespace() &&
1001 cast<NamespaceDecl>(DC)->getIdentifier() &&
1002 cast<NamespaceDecl>(DC)->getIdentifier()->isStr("__detail")) {
1003 DeclContext *DCParent = DC->getParent();
1004 if (DCParent->isNamespace() &&
1005 cast<NamespaceDecl>(DCParent)->getIdentifier() &&
1006 cast<NamespaceDecl>(DCParent)->getIdentifier()->isStr("tr1")) {
1007 if (cast<Decl>(DCParent)->isInStdNamespace())
1012 TemplateParameterList *PrevParams
1013 = PrevClassTemplate->getTemplateParameters();
1015 // Make sure the parameter lists match.
1016 if (!SemaRef.TemplateParameterListsAreEqual(InstParams, PrevParams,
1018 Sema::TPL_TemplateMatch)) {
1022 AdoptedPreviousTemplateParams = true;
1023 InstParams = PrevParams;
1026 // Do some additional validation, then merge default arguments
1027 // from the existing declarations.
1028 if (!AdoptedPreviousTemplateParams &&
1029 SemaRef.CheckTemplateParameterList(InstParams, PrevParams,
1030 Sema::TPC_ClassTemplate))
1035 CXXRecordDecl *RecordInst
1036 = CXXRecordDecl::Create(SemaRef.Context, Pattern->getTagKind(), DC,
1037 Pattern->getLocStart(), Pattern->getLocation(),
1038 Pattern->getIdentifier(), PrevDecl,
1039 /*DelayTypeCreation=*/true);
1042 RecordInst->setQualifierInfo(QualifierLoc);
1044 ClassTemplateDecl *Inst
1045 = ClassTemplateDecl::Create(SemaRef.Context, DC, D->getLocation(),
1046 D->getIdentifier(), InstParams, RecordInst,
1048 RecordInst->setDescribedClassTemplate(Inst);
1051 if (PrevClassTemplate)
1052 Inst->setAccess(PrevClassTemplate->getAccess());
1054 Inst->setAccess(D->getAccess());
1056 Inst->setObjectOfFriendDecl();
1057 // TODO: do we want to track the instantiation progeny of this
1058 // friend target decl?
1060 Inst->setAccess(D->getAccess());
1061 if (!PrevClassTemplate)
1062 Inst->setInstantiatedFromMemberTemplate(D);
1065 // Trigger creation of the type for the instantiation.
1066 SemaRef.Context.getInjectedClassNameType(RecordInst,
1067 Inst->getInjectedClassNameSpecialization());
1069 // Finish handling of friends.
1071 DC->makeDeclVisibleInContext(Inst);
1072 Inst->setLexicalDeclContext(Owner);
1073 RecordInst->setLexicalDeclContext(Owner);
1077 if (D->isOutOfLine()) {
1078 Inst->setLexicalDeclContext(D->getLexicalDeclContext());
1079 RecordInst->setLexicalDeclContext(D->getLexicalDeclContext());
1082 Owner->addDecl(Inst);
1084 if (!PrevClassTemplate) {
1085 // Queue up any out-of-line partial specializations of this member
1086 // class template; the client will force their instantiation once
1087 // the enclosing class has been instantiated.
1088 SmallVector<ClassTemplatePartialSpecializationDecl *, 4> PartialSpecs;
1089 D->getPartialSpecializations(PartialSpecs);
1090 for (unsigned I = 0, N = PartialSpecs.size(); I != N; ++I)
1091 if (PartialSpecs[I]->getFirstDecl()->isOutOfLine())
1092 OutOfLinePartialSpecs.push_back(std::make_pair(Inst, PartialSpecs[I]));
1099 TemplateDeclInstantiator::VisitClassTemplatePartialSpecializationDecl(
1100 ClassTemplatePartialSpecializationDecl *D) {
1101 ClassTemplateDecl *ClassTemplate = D->getSpecializedTemplate();
1103 // Lookup the already-instantiated declaration in the instantiation
1104 // of the class template and return that.
1105 DeclContext::lookup_result Found
1106 = Owner->lookup(ClassTemplate->getDeclName());
1110 ClassTemplateDecl *InstClassTemplate
1111 = dyn_cast<ClassTemplateDecl>(Found.front());
1112 if (!InstClassTemplate)
1115 if (ClassTemplatePartialSpecializationDecl *Result
1116 = InstClassTemplate->findPartialSpecInstantiatedFromMember(D))
1119 return InstantiateClassTemplatePartialSpecialization(InstClassTemplate, D);
1122 Decl *TemplateDeclInstantiator::VisitVarTemplateDecl(VarTemplateDecl *D) {
1123 assert(D->getTemplatedDecl()->isStaticDataMember() &&
1124 "Only static data member templates are allowed.");
1126 // Create a local instantiation scope for this variable template, which
1127 // will contain the instantiations of the template parameters.
1128 LocalInstantiationScope Scope(SemaRef);
1129 TemplateParameterList *TempParams = D->getTemplateParameters();
1130 TemplateParameterList *InstParams = SubstTemplateParams(TempParams);
1134 VarDecl *Pattern = D->getTemplatedDecl();
1135 VarTemplateDecl *PrevVarTemplate = nullptr;
1137 if (getPreviousDeclForInstantiation(Pattern)) {
1138 DeclContext::lookup_result Found = Owner->lookup(Pattern->getDeclName());
1140 PrevVarTemplate = dyn_cast<VarTemplateDecl>(Found.front());
1144 cast_or_null<VarDecl>(VisitVarDecl(Pattern,
1145 /*InstantiatingVarTemplate=*/true));
1147 DeclContext *DC = Owner;
1149 VarTemplateDecl *Inst = VarTemplateDecl::Create(
1150 SemaRef.Context, DC, D->getLocation(), D->getIdentifier(), InstParams,
1152 VarInst->setDescribedVarTemplate(Inst);
1153 Inst->setPreviousDecl(PrevVarTemplate);
1155 Inst->setAccess(D->getAccess());
1156 if (!PrevVarTemplate)
1157 Inst->setInstantiatedFromMemberTemplate(D);
1159 if (D->isOutOfLine()) {
1160 Inst->setLexicalDeclContext(D->getLexicalDeclContext());
1161 VarInst->setLexicalDeclContext(D->getLexicalDeclContext());
1164 Owner->addDecl(Inst);
1166 if (!PrevVarTemplate) {
1167 // Queue up any out-of-line partial specializations of this member
1168 // variable template; the client will force their instantiation once
1169 // the enclosing class has been instantiated.
1170 SmallVector<VarTemplatePartialSpecializationDecl *, 4> PartialSpecs;
1171 D->getPartialSpecializations(PartialSpecs);
1172 for (unsigned I = 0, N = PartialSpecs.size(); I != N; ++I)
1173 if (PartialSpecs[I]->getFirstDecl()->isOutOfLine())
1174 OutOfLineVarPartialSpecs.push_back(
1175 std::make_pair(Inst, PartialSpecs[I]));
1181 Decl *TemplateDeclInstantiator::VisitVarTemplatePartialSpecializationDecl(
1182 VarTemplatePartialSpecializationDecl *D) {
1183 assert(D->isStaticDataMember() &&
1184 "Only static data member templates are allowed.");
1186 VarTemplateDecl *VarTemplate = D->getSpecializedTemplate();
1188 // Lookup the already-instantiated declaration and return that.
1189 DeclContext::lookup_result Found = Owner->lookup(VarTemplate->getDeclName());
1190 assert(!Found.empty() && "Instantiation found nothing?");
1192 VarTemplateDecl *InstVarTemplate = dyn_cast<VarTemplateDecl>(Found.front());
1193 assert(InstVarTemplate && "Instantiation did not find a variable template?");
1195 if (VarTemplatePartialSpecializationDecl *Result =
1196 InstVarTemplate->findPartialSpecInstantiatedFromMember(D))
1199 return InstantiateVarTemplatePartialSpecialization(InstVarTemplate, D);
1203 TemplateDeclInstantiator::VisitFunctionTemplateDecl(FunctionTemplateDecl *D) {
1204 // Create a local instantiation scope for this function template, which
1205 // will contain the instantiations of the template parameters and then get
1206 // merged with the local instantiation scope for the function template
1208 LocalInstantiationScope Scope(SemaRef);
1210 TemplateParameterList *TempParams = D->getTemplateParameters();
1211 TemplateParameterList *InstParams = SubstTemplateParams(TempParams);
1215 FunctionDecl *Instantiated = nullptr;
1216 if (CXXMethodDecl *DMethod = dyn_cast<CXXMethodDecl>(D->getTemplatedDecl()))
1217 Instantiated = cast_or_null<FunctionDecl>(VisitCXXMethodDecl(DMethod,
1220 Instantiated = cast_or_null<FunctionDecl>(VisitFunctionDecl(
1221 D->getTemplatedDecl(),
1227 // Link the instantiated function template declaration to the function
1228 // template from which it was instantiated.
1229 FunctionTemplateDecl *InstTemplate
1230 = Instantiated->getDescribedFunctionTemplate();
1231 InstTemplate->setAccess(D->getAccess());
1232 assert(InstTemplate &&
1233 "VisitFunctionDecl/CXXMethodDecl didn't create a template!");
1235 bool isFriend = (InstTemplate->getFriendObjectKind() != Decl::FOK_None);
1237 // Link the instantiation back to the pattern *unless* this is a
1238 // non-definition friend declaration.
1239 if (!InstTemplate->getInstantiatedFromMemberTemplate() &&
1240 !(isFriend && !D->getTemplatedDecl()->isThisDeclarationADefinition()))
1241 InstTemplate->setInstantiatedFromMemberTemplate(D);
1243 // Make declarations visible in the appropriate context.
1245 Owner->addDecl(InstTemplate);
1246 } else if (InstTemplate->getDeclContext()->isRecord() &&
1247 !getPreviousDeclForInstantiation(D)) {
1248 SemaRef.CheckFriendAccess(InstTemplate);
1251 return InstTemplate;
1254 Decl *TemplateDeclInstantiator::VisitCXXRecordDecl(CXXRecordDecl *D) {
1255 CXXRecordDecl *PrevDecl = nullptr;
1256 if (D->isInjectedClassName())
1257 PrevDecl = cast<CXXRecordDecl>(Owner);
1258 else if (CXXRecordDecl *PatternPrev = getPreviousDeclForInstantiation(D)) {
1259 NamedDecl *Prev = SemaRef.FindInstantiatedDecl(D->getLocation(),
1262 if (!Prev) return nullptr;
1263 PrevDecl = cast<CXXRecordDecl>(Prev);
1266 CXXRecordDecl *Record
1267 = CXXRecordDecl::Create(SemaRef.Context, D->getTagKind(), Owner,
1268 D->getLocStart(), D->getLocation(),
1269 D->getIdentifier(), PrevDecl);
1271 // Substitute the nested name specifier, if any.
1272 if (SubstQualifier(D, Record))
1275 Record->setImplicit(D->isImplicit());
1276 // FIXME: Check against AS_none is an ugly hack to work around the issue that
1277 // the tag decls introduced by friend class declarations don't have an access
1278 // specifier. Remove once this area of the code gets sorted out.
1279 if (D->getAccess() != AS_none)
1280 Record->setAccess(D->getAccess());
1281 if (!D->isInjectedClassName())
1282 Record->setInstantiationOfMemberClass(D, TSK_ImplicitInstantiation);
1284 // If the original function was part of a friend declaration,
1285 // inherit its namespace state.
1286 if (D->getFriendObjectKind())
1287 Record->setObjectOfFriendDecl();
1289 // Make sure that anonymous structs and unions are recorded.
1290 if (D->isAnonymousStructOrUnion())
1291 Record->setAnonymousStructOrUnion(true);
1293 if (D->isLocalClass())
1294 SemaRef.CurrentInstantiationScope->InstantiatedLocal(D, Record);
1296 // Forward the mangling number from the template to the instantiated decl.
1297 SemaRef.Context.setManglingNumber(Record,
1298 SemaRef.Context.getManglingNumber(D));
1300 Owner->addDecl(Record);
1302 // DR1484 clarifies that the members of a local class are instantiated as part
1303 // of the instantiation of their enclosing entity.
1304 if (D->isCompleteDefinition() && D->isLocalClass()) {
1305 Sema::SavePendingLocalImplicitInstantiationsRAII
1306 SavedPendingLocalImplicitInstantiations(SemaRef);
1308 SemaRef.InstantiateClass(D->getLocation(), Record, D, TemplateArgs,
1309 TSK_ImplicitInstantiation,
1312 SemaRef.InstantiateClassMembers(D->getLocation(), Record, TemplateArgs,
1313 TSK_ImplicitInstantiation);
1315 // This class may have local implicit instantiations that need to be
1316 // performed within this scope.
1317 SemaRef.PerformPendingInstantiations(/*LocalOnly=*/true);
1320 SemaRef.DiagnoseUnusedNestedTypedefs(Record);
1325 /// \brief Adjust the given function type for an instantiation of the
1326 /// given declaration, to cope with modifications to the function's type that
1327 /// aren't reflected in the type-source information.
1329 /// \param D The declaration we're instantiating.
1330 /// \param TInfo The already-instantiated type.
1331 static QualType adjustFunctionTypeForInstantiation(ASTContext &Context,
1333 TypeSourceInfo *TInfo) {
1334 const FunctionProtoType *OrigFunc
1335 = D->getType()->castAs<FunctionProtoType>();
1336 const FunctionProtoType *NewFunc
1337 = TInfo->getType()->castAs<FunctionProtoType>();
1338 if (OrigFunc->getExtInfo() == NewFunc->getExtInfo())
1339 return TInfo->getType();
1341 FunctionProtoType::ExtProtoInfo NewEPI = NewFunc->getExtProtoInfo();
1342 NewEPI.ExtInfo = OrigFunc->getExtInfo();
1343 return Context.getFunctionType(NewFunc->getReturnType(),
1344 NewFunc->getParamTypes(), NewEPI);
1347 /// Normal class members are of more specific types and therefore
1348 /// don't make it here. This function serves two purposes:
1349 /// 1) instantiating function templates
1350 /// 2) substituting friend declarations
1351 Decl *TemplateDeclInstantiator::VisitFunctionDecl(FunctionDecl *D,
1352 TemplateParameterList *TemplateParams) {
1353 // Check whether there is already a function template specialization for
1354 // this declaration.
1355 FunctionTemplateDecl *FunctionTemplate = D->getDescribedFunctionTemplate();
1356 if (FunctionTemplate && !TemplateParams) {
1357 ArrayRef<TemplateArgument> Innermost = TemplateArgs.getInnermost();
1359 void *InsertPos = nullptr;
1360 FunctionDecl *SpecFunc
1361 = FunctionTemplate->findSpecialization(Innermost, InsertPos);
1363 // If we already have a function template specialization, return it.
1369 if (FunctionTemplate)
1370 isFriend = (FunctionTemplate->getFriendObjectKind() != Decl::FOK_None);
1372 isFriend = (D->getFriendObjectKind() != Decl::FOK_None);
1374 bool MergeWithParentScope = (TemplateParams != nullptr) ||
1375 Owner->isFunctionOrMethod() ||
1376 !(isa<Decl>(Owner) &&
1377 cast<Decl>(Owner)->isDefinedOutsideFunctionOrMethod());
1378 LocalInstantiationScope Scope(SemaRef, MergeWithParentScope);
1380 SmallVector<ParmVarDecl *, 4> Params;
1381 TypeSourceInfo *TInfo = SubstFunctionType(D, Params);
1384 QualType T = adjustFunctionTypeForInstantiation(SemaRef.Context, D, TInfo);
1386 NestedNameSpecifierLoc QualifierLoc = D->getQualifierLoc();
1388 QualifierLoc = SemaRef.SubstNestedNameSpecifierLoc(QualifierLoc,
1394 // If we're instantiating a local function declaration, put the result
1395 // in the enclosing namespace; otherwise we need to find the instantiated
1398 if (D->isLocalExternDecl()) {
1400 SemaRef.adjustContextForLocalExternDecl(DC);
1401 } else if (isFriend && QualifierLoc) {
1403 SS.Adopt(QualifierLoc);
1404 DC = SemaRef.computeDeclContext(SS);
1405 if (!DC) return nullptr;
1407 DC = SemaRef.FindInstantiatedContext(D->getLocation(), D->getDeclContext(),
1411 FunctionDecl *Function =
1412 FunctionDecl::Create(SemaRef.Context, DC, D->getInnerLocStart(),
1413 D->getNameInfo(), T, TInfo,
1414 D->getCanonicalDecl()->getStorageClass(),
1415 D->isInlineSpecified(), D->hasWrittenPrototype(),
1417 Function->setRangeEnd(D->getSourceRange().getEnd());
1420 Function->setImplicitlyInline();
1423 Function->setQualifierInfo(QualifierLoc);
1425 if (D->isLocalExternDecl())
1426 Function->setLocalExternDecl();
1428 DeclContext *LexicalDC = Owner;
1429 if (!isFriend && D->isOutOfLine() && !D->isLocalExternDecl()) {
1430 assert(D->getDeclContext()->isFileContext());
1431 LexicalDC = D->getDeclContext();
1434 Function->setLexicalDeclContext(LexicalDC);
1436 // Attach the parameters
1437 for (unsigned P = 0; P < Params.size(); ++P)
1439 Params[P]->setOwningFunction(Function);
1440 Function->setParams(Params);
1442 SourceLocation InstantiateAtPOI;
1443 if (TemplateParams) {
1444 // Our resulting instantiation is actually a function template, since we
1445 // are substituting only the outer template parameters. For example, given
1447 // template<typename T>
1449 // template<typename U> friend void f(T, U);
1454 // We are instantiating the friend function template "f" within X<int>,
1455 // which means substituting int for T, but leaving "f" as a friend function
1457 // Build the function template itself.
1458 FunctionTemplate = FunctionTemplateDecl::Create(SemaRef.Context, DC,
1459 Function->getLocation(),
1460 Function->getDeclName(),
1461 TemplateParams, Function);
1462 Function->setDescribedFunctionTemplate(FunctionTemplate);
1464 FunctionTemplate->setLexicalDeclContext(LexicalDC);
1466 if (isFriend && D->isThisDeclarationADefinition()) {
1467 // TODO: should we remember this connection regardless of whether
1468 // the friend declaration provided a body?
1469 FunctionTemplate->setInstantiatedFromMemberTemplate(
1470 D->getDescribedFunctionTemplate());
1472 } else if (FunctionTemplate) {
1473 // Record this function template specialization.
1474 ArrayRef<TemplateArgument> Innermost = TemplateArgs.getInnermost();
1475 Function->setFunctionTemplateSpecialization(FunctionTemplate,
1476 TemplateArgumentList::CreateCopy(SemaRef.Context,
1479 /*InsertPos=*/nullptr);
1480 } else if (isFriend) {
1481 // Note, we need this connection even if the friend doesn't have a body.
1482 // Its body may exist but not have been attached yet due to deferred
1484 // FIXME: It might be cleaner to set this when attaching the body to the
1485 // friend function declaration, however that would require finding all the
1486 // instantiations and modifying them.
1487 Function->setInstantiationOfMemberFunction(D, TSK_ImplicitInstantiation);
1490 if (InitFunctionInstantiation(Function, D))
1491 Function->setInvalidDecl();
1493 bool isExplicitSpecialization = false;
1495 LookupResult Previous(
1496 SemaRef, Function->getDeclName(), SourceLocation(),
1497 D->isLocalExternDecl() ? Sema::LookupRedeclarationWithLinkage
1498 : Sema::LookupOrdinaryName,
1499 Sema::ForRedeclaration);
1501 if (DependentFunctionTemplateSpecializationInfo *Info
1502 = D->getDependentSpecializationInfo()) {
1503 assert(isFriend && "non-friend has dependent specialization info?");
1505 // This needs to be set now for future sanity.
1506 Function->setObjectOfFriendDecl();
1508 // Instantiate the explicit template arguments.
1509 TemplateArgumentListInfo ExplicitArgs(Info->getLAngleLoc(),
1510 Info->getRAngleLoc());
1511 if (SemaRef.Subst(Info->getTemplateArgs(), Info->getNumTemplateArgs(),
1512 ExplicitArgs, TemplateArgs))
1515 // Map the candidate templates to their instantiations.
1516 for (unsigned I = 0, E = Info->getNumTemplates(); I != E; ++I) {
1517 Decl *Temp = SemaRef.FindInstantiatedDecl(D->getLocation(),
1518 Info->getTemplate(I),
1520 if (!Temp) return nullptr;
1522 Previous.addDecl(cast<FunctionTemplateDecl>(Temp));
1525 if (SemaRef.CheckFunctionTemplateSpecialization(Function,
1528 Function->setInvalidDecl();
1530 isExplicitSpecialization = true;
1532 } else if (TemplateParams || !FunctionTemplate) {
1533 // Look only into the namespace where the friend would be declared to
1534 // find a previous declaration. This is the innermost enclosing namespace,
1535 // as described in ActOnFriendFunctionDecl.
1536 SemaRef.LookupQualifiedName(Previous, DC);
1538 // In C++, the previous declaration we find might be a tag type
1539 // (class or enum). In this case, the new declaration will hide the
1540 // tag type. Note that this does does not apply if we're declaring a
1541 // typedef (C++ [dcl.typedef]p4).
1542 if (Previous.isSingleTagDecl())
1546 SemaRef.CheckFunctionDeclaration(/*Scope*/ nullptr, Function, Previous,
1547 isExplicitSpecialization);
1549 NamedDecl *PrincipalDecl = (TemplateParams
1550 ? cast<NamedDecl>(FunctionTemplate)
1553 // If the original function was part of a friend declaration,
1554 // inherit its namespace state and add it to the owner.
1556 PrincipalDecl->setObjectOfFriendDecl();
1557 DC->makeDeclVisibleInContext(PrincipalDecl);
1559 bool QueuedInstantiation = false;
1561 // C++11 [temp.friend]p4 (DR329):
1562 // When a function is defined in a friend function declaration in a class
1563 // template, the function is instantiated when the function is odr-used.
1564 // The same restrictions on multiple declarations and definitions that
1565 // apply to non-template function declarations and definitions also apply
1566 // to these implicit definitions.
1567 if (D->isThisDeclarationADefinition()) {
1568 // Check for a function body.
1569 const FunctionDecl *Definition = nullptr;
1570 if (Function->isDefined(Definition) &&
1571 Definition->getTemplateSpecializationKind() == TSK_Undeclared) {
1572 SemaRef.Diag(Function->getLocation(), diag::err_redefinition)
1573 << Function->getDeclName();
1574 SemaRef.Diag(Definition->getLocation(), diag::note_previous_definition);
1576 // Check for redefinitions due to other instantiations of this or
1577 // a similar friend function.
1578 else for (auto R : Function->redecls()) {
1582 // If some prior declaration of this function has been used, we need
1583 // to instantiate its definition.
1584 if (!QueuedInstantiation && R->isUsed(false)) {
1585 if (MemberSpecializationInfo *MSInfo =
1586 Function->getMemberSpecializationInfo()) {
1587 if (MSInfo->getPointOfInstantiation().isInvalid()) {
1588 SourceLocation Loc = R->getLocation(); // FIXME
1589 MSInfo->setPointOfInstantiation(Loc);
1590 SemaRef.PendingLocalImplicitInstantiations.push_back(
1591 std::make_pair(Function, Loc));
1592 QueuedInstantiation = true;
1597 // If some prior declaration of this function was a friend with an
1598 // uninstantiated definition, reject it.
1599 if (R->getFriendObjectKind()) {
1600 if (const FunctionDecl *RPattern =
1601 R->getTemplateInstantiationPattern()) {
1602 if (RPattern->isDefined(RPattern)) {
1603 SemaRef.Diag(Function->getLocation(), diag::err_redefinition)
1604 << Function->getDeclName();
1605 SemaRef.Diag(R->getLocation(), diag::note_previous_definition);
1614 if (Function->isLocalExternDecl() && !Function->getPreviousDecl())
1615 DC->makeDeclVisibleInContext(PrincipalDecl);
1617 if (Function->isOverloadedOperator() && !DC->isRecord() &&
1618 PrincipalDecl->isInIdentifierNamespace(Decl::IDNS_Ordinary))
1619 PrincipalDecl->setNonMemberOperator();
1621 assert(!D->isDefaulted() && "only methods should be defaulted");
1626 TemplateDeclInstantiator::VisitCXXMethodDecl(CXXMethodDecl *D,
1627 TemplateParameterList *TemplateParams,
1628 bool IsClassScopeSpecialization) {
1629 FunctionTemplateDecl *FunctionTemplate = D->getDescribedFunctionTemplate();
1630 if (FunctionTemplate && !TemplateParams) {
1631 // We are creating a function template specialization from a function
1632 // template. Check whether there is already a function template
1633 // specialization for this particular set of template arguments.
1634 ArrayRef<TemplateArgument> Innermost = TemplateArgs.getInnermost();
1636 void *InsertPos = nullptr;
1637 FunctionDecl *SpecFunc
1638 = FunctionTemplate->findSpecialization(Innermost, InsertPos);
1640 // If we already have a function template specialization, return it.
1646 if (FunctionTemplate)
1647 isFriend = (FunctionTemplate->getFriendObjectKind() != Decl::FOK_None);
1649 isFriend = (D->getFriendObjectKind() != Decl::FOK_None);
1651 bool MergeWithParentScope = (TemplateParams != nullptr) ||
1652 !(isa<Decl>(Owner) &&
1653 cast<Decl>(Owner)->isDefinedOutsideFunctionOrMethod());
1654 LocalInstantiationScope Scope(SemaRef, MergeWithParentScope);
1656 // Instantiate enclosing template arguments for friends.
1657 SmallVector<TemplateParameterList *, 4> TempParamLists;
1658 unsigned NumTempParamLists = 0;
1659 if (isFriend && (NumTempParamLists = D->getNumTemplateParameterLists())) {
1660 TempParamLists.set_size(NumTempParamLists);
1661 for (unsigned I = 0; I != NumTempParamLists; ++I) {
1662 TemplateParameterList *TempParams = D->getTemplateParameterList(I);
1663 TemplateParameterList *InstParams = SubstTemplateParams(TempParams);
1666 TempParamLists[I] = InstParams;
1670 SmallVector<ParmVarDecl *, 4> Params;
1671 TypeSourceInfo *TInfo = SubstFunctionType(D, Params);
1674 QualType T = adjustFunctionTypeForInstantiation(SemaRef.Context, D, TInfo);
1676 NestedNameSpecifierLoc QualifierLoc = D->getQualifierLoc();
1678 QualifierLoc = SemaRef.SubstNestedNameSpecifierLoc(QualifierLoc,
1684 DeclContext *DC = Owner;
1688 SS.Adopt(QualifierLoc);
1689 DC = SemaRef.computeDeclContext(SS);
1691 if (DC && SemaRef.RequireCompleteDeclContext(SS, DC))
1694 DC = SemaRef.FindInstantiatedContext(D->getLocation(),
1695 D->getDeclContext(),
1698 if (!DC) return nullptr;
1701 // Build the instantiated method declaration.
1702 CXXRecordDecl *Record = cast<CXXRecordDecl>(DC);
1703 CXXMethodDecl *Method = nullptr;
1705 SourceLocation StartLoc = D->getInnerLocStart();
1706 DeclarationNameInfo NameInfo
1707 = SemaRef.SubstDeclarationNameInfo(D->getNameInfo(), TemplateArgs);
1708 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(D)) {
1709 Method = CXXConstructorDecl::Create(SemaRef.Context, Record,
1710 StartLoc, NameInfo, T, TInfo,
1711 Constructor->isExplicit(),
1712 Constructor->isInlineSpecified(),
1713 false, Constructor->isConstexpr());
1715 // Claim that the instantiation of a constructor or constructor template
1716 // inherits the same constructor that the template does.
1717 if (CXXConstructorDecl *Inh = const_cast<CXXConstructorDecl *>(
1718 Constructor->getInheritedConstructor())) {
1719 // If we're instantiating a specialization of a function template, our
1720 // "inherited constructor" will actually itself be a function template.
1721 // Instantiate a declaration of it, too.
1722 if (FunctionTemplate) {
1723 assert(!TemplateParams && Inh->getDescribedFunctionTemplate() &&
1724 !Inh->getParent()->isDependentContext() &&
1725 "inheriting constructor template in dependent context?");
1726 Sema::InstantiatingTemplate Inst(SemaRef, Constructor->getLocation(),
1728 if (Inst.isInvalid())
1730 Sema::ContextRAII SavedContext(SemaRef, Inh->getDeclContext());
1731 LocalInstantiationScope LocalScope(SemaRef);
1733 // Use the same template arguments that we deduced for the inheriting
1734 // constructor. There's no way they could be deduced differently.
1735 MultiLevelTemplateArgumentList InheritedArgs;
1736 InheritedArgs.addOuterTemplateArguments(TemplateArgs.getInnermost());
1737 Inh = cast_or_null<CXXConstructorDecl>(
1738 SemaRef.SubstDecl(Inh, Inh->getDeclContext(), InheritedArgs));
1742 cast<CXXConstructorDecl>(Method)->setInheritedConstructor(Inh);
1744 } else if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(D)) {
1745 Method = CXXDestructorDecl::Create(SemaRef.Context, Record,
1746 StartLoc, NameInfo, T, TInfo,
1747 Destructor->isInlineSpecified(),
1749 } else if (CXXConversionDecl *Conversion = dyn_cast<CXXConversionDecl>(D)) {
1750 Method = CXXConversionDecl::Create(SemaRef.Context, Record,
1751 StartLoc, NameInfo, T, TInfo,
1752 Conversion->isInlineSpecified(),
1753 Conversion->isExplicit(),
1754 Conversion->isConstexpr(),
1755 Conversion->getLocEnd());
1757 StorageClass SC = D->isStatic() ? SC_Static : SC_None;
1758 Method = CXXMethodDecl::Create(SemaRef.Context, Record,
1759 StartLoc, NameInfo, T, TInfo,
1760 SC, D->isInlineSpecified(),
1761 D->isConstexpr(), D->getLocEnd());
1765 Method->setImplicitlyInline();
1768 Method->setQualifierInfo(QualifierLoc);
1770 if (TemplateParams) {
1771 // Our resulting instantiation is actually a function template, since we
1772 // are substituting only the outer template parameters. For example, given
1774 // template<typename T>
1776 // template<typename U> void f(T, U);
1781 // We are instantiating the member template "f" within X<int>, which means
1782 // substituting int for T, but leaving "f" as a member function template.
1783 // Build the function template itself.
1784 FunctionTemplate = FunctionTemplateDecl::Create(SemaRef.Context, Record,
1785 Method->getLocation(),
1786 Method->getDeclName(),
1787 TemplateParams, Method);
1789 FunctionTemplate->setLexicalDeclContext(Owner);
1790 FunctionTemplate->setObjectOfFriendDecl();
1791 } else if (D->isOutOfLine())
1792 FunctionTemplate->setLexicalDeclContext(D->getLexicalDeclContext());
1793 Method->setDescribedFunctionTemplate(FunctionTemplate);
1794 } else if (FunctionTemplate) {
1795 // Record this function template specialization.
1796 ArrayRef<TemplateArgument> Innermost = TemplateArgs.getInnermost();
1797 Method->setFunctionTemplateSpecialization(FunctionTemplate,
1798 TemplateArgumentList::CreateCopy(SemaRef.Context,
1801 /*InsertPos=*/nullptr);
1802 } else if (!isFriend) {
1803 // Record that this is an instantiation of a member function.
1804 Method->setInstantiationOfMemberFunction(D, TSK_ImplicitInstantiation);
1807 // If we are instantiating a member function defined
1808 // out-of-line, the instantiation will have the same lexical
1809 // context (which will be a namespace scope) as the template.
1811 if (NumTempParamLists)
1812 Method->setTemplateParameterListsInfo(SemaRef.Context,
1814 TempParamLists.data());
1816 Method->setLexicalDeclContext(Owner);
1817 Method->setObjectOfFriendDecl();
1818 } else if (D->isOutOfLine())
1819 Method->setLexicalDeclContext(D->getLexicalDeclContext());
1821 // Attach the parameters
1822 for (unsigned P = 0; P < Params.size(); ++P)
1823 Params[P]->setOwningFunction(Method);
1824 Method->setParams(Params);
1826 if (InitMethodInstantiation(Method, D))
1827 Method->setInvalidDecl();
1829 LookupResult Previous(SemaRef, NameInfo, Sema::LookupOrdinaryName,
1830 Sema::ForRedeclaration);
1832 if (!FunctionTemplate || TemplateParams || isFriend) {
1833 SemaRef.LookupQualifiedName(Previous, Record);
1835 // In C++, the previous declaration we find might be a tag type
1836 // (class or enum). In this case, the new declaration will hide the
1837 // tag type. Note that this does does not apply if we're declaring a
1838 // typedef (C++ [dcl.typedef]p4).
1839 if (Previous.isSingleTagDecl())
1843 if (!IsClassScopeSpecialization)
1844 SemaRef.CheckFunctionDeclaration(nullptr, Method, Previous, false);
1847 SemaRef.CheckPureMethod(Method, SourceRange());
1849 // Propagate access. For a non-friend declaration, the access is
1850 // whatever we're propagating from. For a friend, it should be the
1851 // previous declaration we just found.
1852 if (isFriend && Method->getPreviousDecl())
1853 Method->setAccess(Method->getPreviousDecl()->getAccess());
1855 Method->setAccess(D->getAccess());
1856 if (FunctionTemplate)
1857 FunctionTemplate->setAccess(Method->getAccess());
1859 SemaRef.CheckOverrideControl(Method);
1861 // If a function is defined as defaulted or deleted, mark it as such now.
1862 if (D->isExplicitlyDefaulted())
1863 SemaRef.SetDeclDefaulted(Method, Method->getLocation());
1864 if (D->isDeletedAsWritten())
1865 SemaRef.SetDeclDeleted(Method, Method->getLocation());
1867 // If there's a function template, let our caller handle it.
1868 if (FunctionTemplate) {
1871 // Don't hide a (potentially) valid declaration with an invalid one.
1872 } else if (Method->isInvalidDecl() && !Previous.empty()) {
1875 // Otherwise, check access to friends and make them visible.
1876 } else if (isFriend) {
1877 // We only need to re-check access for methods which we didn't
1878 // manage to match during parsing.
1879 if (!D->getPreviousDecl())
1880 SemaRef.CheckFriendAccess(Method);
1882 Record->makeDeclVisibleInContext(Method);
1884 // Otherwise, add the declaration. We don't need to do this for
1885 // class-scope specializations because we'll have matched them with
1886 // the appropriate template.
1887 } else if (!IsClassScopeSpecialization) {
1888 Owner->addDecl(Method);
1894 Decl *TemplateDeclInstantiator::VisitCXXConstructorDecl(CXXConstructorDecl *D) {
1895 return VisitCXXMethodDecl(D);
1898 Decl *TemplateDeclInstantiator::VisitCXXDestructorDecl(CXXDestructorDecl *D) {
1899 return VisitCXXMethodDecl(D);
1902 Decl *TemplateDeclInstantiator::VisitCXXConversionDecl(CXXConversionDecl *D) {
1903 return VisitCXXMethodDecl(D);
1906 Decl *TemplateDeclInstantiator::VisitParmVarDecl(ParmVarDecl *D) {
1907 return SemaRef.SubstParmVarDecl(D, TemplateArgs, /*indexAdjustment*/ 0, None,
1908 /*ExpectParameterPack=*/ false);
1911 Decl *TemplateDeclInstantiator::VisitTemplateTypeParmDecl(
1912 TemplateTypeParmDecl *D) {
1913 // TODO: don't always clone when decls are refcounted.
1914 assert(D->getTypeForDecl()->isTemplateTypeParmType());
1916 TemplateTypeParmDecl *Inst =
1917 TemplateTypeParmDecl::Create(SemaRef.Context, Owner,
1918 D->getLocStart(), D->getLocation(),
1919 D->getDepth() - TemplateArgs.getNumLevels(),
1920 D->getIndex(), D->getIdentifier(),
1921 D->wasDeclaredWithTypename(),
1922 D->isParameterPack());
1923 Inst->setAccess(AS_public);
1925 if (D->hasDefaultArgument()) {
1926 TypeSourceInfo *InstantiatedDefaultArg =
1927 SemaRef.SubstType(D->getDefaultArgumentInfo(), TemplateArgs,
1928 D->getDefaultArgumentLoc(), D->getDeclName());
1929 if (InstantiatedDefaultArg)
1930 Inst->setDefaultArgument(InstantiatedDefaultArg, false);
1933 // Introduce this template parameter's instantiation into the instantiation
1935 SemaRef.CurrentInstantiationScope->InstantiatedLocal(D, Inst);
1940 Decl *TemplateDeclInstantiator::VisitNonTypeTemplateParmDecl(
1941 NonTypeTemplateParmDecl *D) {
1942 // Substitute into the type of the non-type template parameter.
1943 TypeLoc TL = D->getTypeSourceInfo()->getTypeLoc();
1944 SmallVector<TypeSourceInfo *, 4> ExpandedParameterPackTypesAsWritten;
1945 SmallVector<QualType, 4> ExpandedParameterPackTypes;
1946 bool IsExpandedParameterPack = false;
1949 bool Invalid = false;
1951 if (D->isExpandedParameterPack()) {
1952 // The non-type template parameter pack is an already-expanded pack
1953 // expansion of types. Substitute into each of the expanded types.
1954 ExpandedParameterPackTypes.reserve(D->getNumExpansionTypes());
1955 ExpandedParameterPackTypesAsWritten.reserve(D->getNumExpansionTypes());
1956 for (unsigned I = 0, N = D->getNumExpansionTypes(); I != N; ++I) {
1957 TypeSourceInfo *NewDI =SemaRef.SubstType(D->getExpansionTypeSourceInfo(I),
1964 ExpandedParameterPackTypesAsWritten.push_back(NewDI);
1965 QualType NewT =SemaRef.CheckNonTypeTemplateParameterType(NewDI->getType(),
1969 ExpandedParameterPackTypes.push_back(NewT);
1972 IsExpandedParameterPack = true;
1973 DI = D->getTypeSourceInfo();
1975 } else if (D->isPackExpansion()) {
1976 // The non-type template parameter pack's type is a pack expansion of types.
1977 // Determine whether we need to expand this parameter pack into separate
1979 PackExpansionTypeLoc Expansion = TL.castAs<PackExpansionTypeLoc>();
1980 TypeLoc Pattern = Expansion.getPatternLoc();
1981 SmallVector<UnexpandedParameterPack, 2> Unexpanded;
1982 SemaRef.collectUnexpandedParameterPacks(Pattern, Unexpanded);
1984 // Determine whether the set of unexpanded parameter packs can and should
1987 bool RetainExpansion = false;
1988 Optional<unsigned> OrigNumExpansions
1989 = Expansion.getTypePtr()->getNumExpansions();
1990 Optional<unsigned> NumExpansions = OrigNumExpansions;
1991 if (SemaRef.CheckParameterPacksForExpansion(Expansion.getEllipsisLoc(),
1992 Pattern.getSourceRange(),
1995 Expand, RetainExpansion,
2000 for (unsigned I = 0; I != *NumExpansions; ++I) {
2001 Sema::ArgumentPackSubstitutionIndexRAII SubstIndex(SemaRef, I);
2002 TypeSourceInfo *NewDI = SemaRef.SubstType(Pattern, TemplateArgs,
2008 ExpandedParameterPackTypesAsWritten.push_back(NewDI);
2009 QualType NewT = SemaRef.CheckNonTypeTemplateParameterType(
2014 ExpandedParameterPackTypes.push_back(NewT);
2017 // Note that we have an expanded parameter pack. The "type" of this
2018 // expanded parameter pack is the original expansion type, but callers
2019 // will end up using the expanded parameter pack types for type-checking.
2020 IsExpandedParameterPack = true;
2021 DI = D->getTypeSourceInfo();
2024 // We cannot fully expand the pack expansion now, so substitute into the
2025 // pattern and create a new pack expansion type.
2026 Sema::ArgumentPackSubstitutionIndexRAII SubstIndex(SemaRef, -1);
2027 TypeSourceInfo *NewPattern = SemaRef.SubstType(Pattern, TemplateArgs,
2033 DI = SemaRef.CheckPackExpansion(NewPattern, Expansion.getEllipsisLoc(),
2041 // Simple case: substitution into a parameter that is not a parameter pack.
2042 DI = SemaRef.SubstType(D->getTypeSourceInfo(), TemplateArgs,
2043 D->getLocation(), D->getDeclName());
2047 // Check that this type is acceptable for a non-type template parameter.
2048 T = SemaRef.CheckNonTypeTemplateParameterType(DI->getType(),
2051 T = SemaRef.Context.IntTy;
2056 NonTypeTemplateParmDecl *Param;
2057 if (IsExpandedParameterPack)
2058 Param = NonTypeTemplateParmDecl::Create(SemaRef.Context, Owner,
2059 D->getInnerLocStart(),
2061 D->getDepth() - TemplateArgs.getNumLevels(),
2063 D->getIdentifier(), T,
2065 ExpandedParameterPackTypes.data(),
2066 ExpandedParameterPackTypes.size(),
2067 ExpandedParameterPackTypesAsWritten.data());
2069 Param = NonTypeTemplateParmDecl::Create(SemaRef.Context, Owner,
2070 D->getInnerLocStart(),
2072 D->getDepth() - TemplateArgs.getNumLevels(),
2074 D->getIdentifier(), T,
2075 D->isParameterPack(), DI);
2077 Param->setAccess(AS_public);
2079 Param->setInvalidDecl();
2081 if (D->hasDefaultArgument()) {
2082 ExprResult Value = SemaRef.SubstExpr(D->getDefaultArgument(), TemplateArgs);
2083 if (!Value.isInvalid())
2084 Param->setDefaultArgument(Value.get(), false);
2087 // Introduce this template parameter's instantiation into the instantiation
2089 SemaRef.CurrentInstantiationScope->InstantiatedLocal(D, Param);
2093 static void collectUnexpandedParameterPacks(
2095 TemplateParameterList *Params,
2096 SmallVectorImpl<UnexpandedParameterPack> &Unexpanded) {
2097 for (TemplateParameterList::const_iterator I = Params->begin(),
2098 E = Params->end(); I != E; ++I) {
2099 if ((*I)->isTemplateParameterPack())
2101 if (NonTypeTemplateParmDecl *NTTP = dyn_cast<NonTypeTemplateParmDecl>(*I))
2102 S.collectUnexpandedParameterPacks(NTTP->getTypeSourceInfo()->getTypeLoc(),
2104 if (TemplateTemplateParmDecl *TTP = dyn_cast<TemplateTemplateParmDecl>(*I))
2105 collectUnexpandedParameterPacks(S, TTP->getTemplateParameters(),
2111 TemplateDeclInstantiator::VisitTemplateTemplateParmDecl(
2112 TemplateTemplateParmDecl *D) {
2113 // Instantiate the template parameter list of the template template parameter.
2114 TemplateParameterList *TempParams = D->getTemplateParameters();
2115 TemplateParameterList *InstParams;
2116 SmallVector<TemplateParameterList*, 8> ExpandedParams;
2118 bool IsExpandedParameterPack = false;
2120 if (D->isExpandedParameterPack()) {
2121 // The template template parameter pack is an already-expanded pack
2122 // expansion of template parameters. Substitute into each of the expanded
2124 ExpandedParams.reserve(D->getNumExpansionTemplateParameters());
2125 for (unsigned I = 0, N = D->getNumExpansionTemplateParameters();
2127 LocalInstantiationScope Scope(SemaRef);
2128 TemplateParameterList *Expansion =
2129 SubstTemplateParams(D->getExpansionTemplateParameters(I));
2132 ExpandedParams.push_back(Expansion);
2135 IsExpandedParameterPack = true;
2136 InstParams = TempParams;
2137 } else if (D->isPackExpansion()) {
2138 // The template template parameter pack expands to a pack of template
2139 // template parameters. Determine whether we need to expand this parameter
2140 // pack into separate parameters.
2141 SmallVector<UnexpandedParameterPack, 2> Unexpanded;
2142 collectUnexpandedParameterPacks(SemaRef, D->getTemplateParameters(),
2145 // Determine whether the set of unexpanded parameter packs can and should
2148 bool RetainExpansion = false;
2149 Optional<unsigned> NumExpansions;
2150 if (SemaRef.CheckParameterPacksForExpansion(D->getLocation(),
2151 TempParams->getSourceRange(),
2154 Expand, RetainExpansion,
2159 for (unsigned I = 0; I != *NumExpansions; ++I) {
2160 Sema::ArgumentPackSubstitutionIndexRAII SubstIndex(SemaRef, I);
2161 LocalInstantiationScope Scope(SemaRef);
2162 TemplateParameterList *Expansion = SubstTemplateParams(TempParams);
2165 ExpandedParams.push_back(Expansion);
2168 // Note that we have an expanded parameter pack. The "type" of this
2169 // expanded parameter pack is the original expansion type, but callers
2170 // will end up using the expanded parameter pack types for type-checking.
2171 IsExpandedParameterPack = true;
2172 InstParams = TempParams;
2174 // We cannot fully expand the pack expansion now, so just substitute
2175 // into the pattern.
2176 Sema::ArgumentPackSubstitutionIndexRAII SubstIndex(SemaRef, -1);
2178 LocalInstantiationScope Scope(SemaRef);
2179 InstParams = SubstTemplateParams(TempParams);
2184 // Perform the actual substitution of template parameters within a new,
2185 // local instantiation scope.
2186 LocalInstantiationScope Scope(SemaRef);
2187 InstParams = SubstTemplateParams(TempParams);
2192 // Build the template template parameter.
2193 TemplateTemplateParmDecl *Param;
2194 if (IsExpandedParameterPack)
2195 Param = TemplateTemplateParmDecl::Create(SemaRef.Context, Owner,
2197 D->getDepth() - TemplateArgs.getNumLevels(),
2199 D->getIdentifier(), InstParams,
2202 Param = TemplateTemplateParmDecl::Create(SemaRef.Context, Owner,
2204 D->getDepth() - TemplateArgs.getNumLevels(),
2206 D->isParameterPack(),
2207 D->getIdentifier(), InstParams);
2208 if (D->hasDefaultArgument()) {
2209 NestedNameSpecifierLoc QualifierLoc =
2210 D->getDefaultArgument().getTemplateQualifierLoc();
2212 SemaRef.SubstNestedNameSpecifierLoc(QualifierLoc, TemplateArgs);
2213 TemplateName TName = SemaRef.SubstTemplateName(
2214 QualifierLoc, D->getDefaultArgument().getArgument().getAsTemplate(),
2215 D->getDefaultArgument().getTemplateNameLoc(), TemplateArgs);
2216 if (!TName.isNull())
2217 Param->setDefaultArgument(
2218 TemplateArgumentLoc(TemplateArgument(TName),
2219 D->getDefaultArgument().getTemplateQualifierLoc(),
2220 D->getDefaultArgument().getTemplateNameLoc()),
2223 Param->setAccess(AS_public);
2225 // Introduce this template parameter's instantiation into the instantiation
2227 SemaRef.CurrentInstantiationScope->InstantiatedLocal(D, Param);
2232 Decl *TemplateDeclInstantiator::VisitUsingDirectiveDecl(UsingDirectiveDecl *D) {
2233 // Using directives are never dependent (and never contain any types or
2234 // expressions), so they require no explicit instantiation work.
2236 UsingDirectiveDecl *Inst
2237 = UsingDirectiveDecl::Create(SemaRef.Context, Owner, D->getLocation(),
2238 D->getNamespaceKeyLocation(),
2239 D->getQualifierLoc(),
2240 D->getIdentLocation(),
2241 D->getNominatedNamespace(),
2242 D->getCommonAncestor());
2244 // Add the using directive to its declaration context
2245 // only if this is not a function or method.
2246 if (!Owner->isFunctionOrMethod())
2247 Owner->addDecl(Inst);
2252 Decl *TemplateDeclInstantiator::VisitUsingDecl(UsingDecl *D) {
2254 // The nested name specifier may be dependent, for example
2255 // template <typename T> struct t {
2256 // struct s1 { T f1(); };
2257 // struct s2 : s1 { using s1::f1; };
2259 // template struct t<int>;
2260 // Here, in using s1::f1, s1 refers to t<T>::s1;
2261 // we need to substitute for t<int>::s1.
2262 NestedNameSpecifierLoc QualifierLoc
2263 = SemaRef.SubstNestedNameSpecifierLoc(D->getQualifierLoc(),
2268 // The name info is non-dependent, so no transformation
2270 DeclarationNameInfo NameInfo = D->getNameInfo();
2272 // We only need to do redeclaration lookups if we're in a class
2273 // scope (in fact, it's not really even possible in non-class
2275 bool CheckRedeclaration = Owner->isRecord();
2277 LookupResult Prev(SemaRef, NameInfo, Sema::LookupUsingDeclName,
2278 Sema::ForRedeclaration);
2280 UsingDecl *NewUD = UsingDecl::Create(SemaRef.Context, Owner,
2287 SS.Adopt(QualifierLoc);
2288 if (CheckRedeclaration) {
2289 Prev.setHideTags(false);
2290 SemaRef.LookupQualifiedName(Prev, Owner);
2292 // Check for invalid redeclarations.
2293 if (SemaRef.CheckUsingDeclRedeclaration(D->getUsingLoc(),
2294 D->hasTypename(), SS,
2295 D->getLocation(), Prev))
2296 NewUD->setInvalidDecl();
2300 if (!NewUD->isInvalidDecl() &&
2301 SemaRef.CheckUsingDeclQualifier(D->getUsingLoc(), SS, NameInfo,
2303 NewUD->setInvalidDecl();
2305 SemaRef.Context.setInstantiatedFromUsingDecl(NewUD, D);
2306 NewUD->setAccess(D->getAccess());
2307 Owner->addDecl(NewUD);
2309 // Don't process the shadow decls for an invalid decl.
2310 if (NewUD->isInvalidDecl())
2313 if (NameInfo.getName().getNameKind() == DeclarationName::CXXConstructorName) {
2314 SemaRef.CheckInheritingConstructorUsingDecl(NewUD);
2318 bool isFunctionScope = Owner->isFunctionOrMethod();
2320 // Process the shadow decls.
2321 for (auto *Shadow : D->shadows()) {
2322 NamedDecl *InstTarget =
2323 cast_or_null<NamedDecl>(SemaRef.FindInstantiatedDecl(
2324 Shadow->getLocation(), Shadow->getTargetDecl(), TemplateArgs));
2328 UsingShadowDecl *PrevDecl = nullptr;
2329 if (CheckRedeclaration) {
2330 if (SemaRef.CheckUsingShadowDecl(NewUD, InstTarget, Prev, PrevDecl))
2332 } else if (UsingShadowDecl *OldPrev =
2333 getPreviousDeclForInstantiation(Shadow)) {
2334 PrevDecl = cast_or_null<UsingShadowDecl>(SemaRef.FindInstantiatedDecl(
2335 Shadow->getLocation(), OldPrev, TemplateArgs));
2338 UsingShadowDecl *InstShadow =
2339 SemaRef.BuildUsingShadowDecl(/*Scope*/nullptr, NewUD, InstTarget,
2341 SemaRef.Context.setInstantiatedFromUsingShadowDecl(InstShadow, Shadow);
2343 if (isFunctionScope)
2344 SemaRef.CurrentInstantiationScope->InstantiatedLocal(Shadow, InstShadow);
2350 Decl *TemplateDeclInstantiator::VisitUsingShadowDecl(UsingShadowDecl *D) {
2351 // Ignore these; we handle them in bulk when processing the UsingDecl.
2355 Decl * TemplateDeclInstantiator
2356 ::VisitUnresolvedUsingTypenameDecl(UnresolvedUsingTypenameDecl *D) {
2357 NestedNameSpecifierLoc QualifierLoc
2358 = SemaRef.SubstNestedNameSpecifierLoc(D->getQualifierLoc(),
2364 SS.Adopt(QualifierLoc);
2366 // Since NameInfo refers to a typename, it cannot be a C++ special name.
2367 // Hence, no transformation is required for it.
2368 DeclarationNameInfo NameInfo(D->getDeclName(), D->getLocation());
2370 SemaRef.BuildUsingDeclaration(/*Scope*/ nullptr, D->getAccess(),
2371 D->getUsingLoc(), SS, NameInfo, nullptr,
2372 /*instantiation*/ true,
2373 /*typename*/ true, D->getTypenameLoc());
2375 SemaRef.Context.setInstantiatedFromUsingDecl(cast<UsingDecl>(UD), D);
2380 Decl * TemplateDeclInstantiator
2381 ::VisitUnresolvedUsingValueDecl(UnresolvedUsingValueDecl *D) {
2382 NestedNameSpecifierLoc QualifierLoc
2383 = SemaRef.SubstNestedNameSpecifierLoc(D->getQualifierLoc(), TemplateArgs);
2388 SS.Adopt(QualifierLoc);
2390 DeclarationNameInfo NameInfo
2391 = SemaRef.SubstDeclarationNameInfo(D->getNameInfo(), TemplateArgs);
2394 SemaRef.BuildUsingDeclaration(/*Scope*/ nullptr, D->getAccess(),
2395 D->getUsingLoc(), SS, NameInfo, nullptr,
2396 /*instantiation*/ true,
2397 /*typename*/ false, SourceLocation());
2399 SemaRef.Context.setInstantiatedFromUsingDecl(cast<UsingDecl>(UD), D);
2405 Decl *TemplateDeclInstantiator::VisitClassScopeFunctionSpecializationDecl(
2406 ClassScopeFunctionSpecializationDecl *Decl) {
2407 CXXMethodDecl *OldFD = Decl->getSpecialization();
2408 CXXMethodDecl *NewFD =
2409 cast_or_null<CXXMethodDecl>(VisitCXXMethodDecl(OldFD, nullptr, true));
2413 LookupResult Previous(SemaRef, NewFD->getNameInfo(), Sema::LookupOrdinaryName,
2414 Sema::ForRedeclaration);
2416 TemplateArgumentListInfo TemplateArgs;
2417 TemplateArgumentListInfo *TemplateArgsPtr = nullptr;
2418 if (Decl->hasExplicitTemplateArgs()) {
2419 TemplateArgs = Decl->templateArgs();
2420 TemplateArgsPtr = &TemplateArgs;
2423 SemaRef.LookupQualifiedName(Previous, SemaRef.CurContext);
2424 if (SemaRef.CheckFunctionTemplateSpecialization(NewFD, TemplateArgsPtr,
2426 NewFD->setInvalidDecl();
2430 // Associate the specialization with the pattern.
2431 FunctionDecl *Specialization = cast<FunctionDecl>(Previous.getFoundDecl());
2432 assert(Specialization && "Class scope Specialization is null");
2433 SemaRef.Context.setClassScopeSpecializationPattern(Specialization, OldFD);
2438 Decl *TemplateDeclInstantiator::VisitOMPThreadPrivateDecl(
2439 OMPThreadPrivateDecl *D) {
2440 SmallVector<Expr *, 5> Vars;
2441 for (auto *I : D->varlists()) {
2442 Expr *Var = SemaRef.SubstExpr(I, TemplateArgs).get();
2443 assert(isa<DeclRefExpr>(Var) && "threadprivate arg is not a DeclRefExpr");
2444 Vars.push_back(Var);
2447 OMPThreadPrivateDecl *TD =
2448 SemaRef.CheckOMPThreadPrivateDecl(D->getLocation(), Vars);
2450 TD->setAccess(AS_public);
2456 Decl *TemplateDeclInstantiator::VisitFunctionDecl(FunctionDecl *D) {
2457 return VisitFunctionDecl(D, nullptr);
2460 Decl *TemplateDeclInstantiator::VisitCXXMethodDecl(CXXMethodDecl *D) {
2461 return VisitCXXMethodDecl(D, nullptr);
2464 Decl *TemplateDeclInstantiator::VisitRecordDecl(RecordDecl *D) {
2465 llvm_unreachable("There are only CXXRecordDecls in C++");
2469 TemplateDeclInstantiator::VisitClassTemplateSpecializationDecl(
2470 ClassTemplateSpecializationDecl *D) {
2471 // As a MS extension, we permit class-scope explicit specialization
2472 // of member class templates.
2473 ClassTemplateDecl *ClassTemplate = D->getSpecializedTemplate();
2474 assert(ClassTemplate->getDeclContext()->isRecord() &&
2475 D->getTemplateSpecializationKind() == TSK_ExplicitSpecialization &&
2476 "can only instantiate an explicit specialization "
2477 "for a member class template");
2479 // Lookup the already-instantiated declaration in the instantiation
2480 // of the class template. FIXME: Diagnose or assert if this fails?
2481 DeclContext::lookup_result Found
2482 = Owner->lookup(ClassTemplate->getDeclName());
2485 ClassTemplateDecl *InstClassTemplate
2486 = dyn_cast<ClassTemplateDecl>(Found.front());
2487 if (!InstClassTemplate)
2490 // Substitute into the template arguments of the class template explicit
2492 TemplateSpecializationTypeLoc Loc = D->getTypeAsWritten()->getTypeLoc().
2493 castAs<TemplateSpecializationTypeLoc>();
2494 TemplateArgumentListInfo InstTemplateArgs(Loc.getLAngleLoc(),
2495 Loc.getRAngleLoc());
2496 SmallVector<TemplateArgumentLoc, 4> ArgLocs;
2497 for (unsigned I = 0; I != Loc.getNumArgs(); ++I)
2498 ArgLocs.push_back(Loc.getArgLoc(I));
2499 if (SemaRef.Subst(ArgLocs.data(), ArgLocs.size(),
2500 InstTemplateArgs, TemplateArgs))
2503 // Check that the template argument list is well-formed for this
2505 SmallVector<TemplateArgument, 4> Converted;
2506 if (SemaRef.CheckTemplateArgumentList(InstClassTemplate,
2513 // Figure out where to insert this class template explicit specialization
2514 // in the member template's set of class template explicit specializations.
2515 void *InsertPos = nullptr;
2516 ClassTemplateSpecializationDecl *PrevDecl =
2517 InstClassTemplate->findSpecialization(Converted, InsertPos);
2519 // Check whether we've already seen a conflicting instantiation of this
2520 // declaration (for instance, if there was a prior implicit instantiation).
2523 SemaRef.CheckSpecializationInstantiationRedecl(D->getLocation(),
2524 D->getSpecializationKind(),
2526 PrevDecl->getSpecializationKind(),
2527 PrevDecl->getPointOfInstantiation(),
2531 // If PrevDecl was a definition and D is also a definition, diagnose.
2532 // This happens in cases like:
2534 // template<typename T, typename U>
2536 // template<typename X> struct Inner;
2537 // template<> struct Inner<T> {};
2538 // template<> struct Inner<U> {};
2541 // Outer<int, int> outer; // error: the explicit specializations of Inner
2542 // // have the same signature.
2543 if (PrevDecl && PrevDecl->getDefinition() &&
2544 D->isThisDeclarationADefinition()) {
2545 SemaRef.Diag(D->getLocation(), diag::err_redefinition) << PrevDecl;
2546 SemaRef.Diag(PrevDecl->getDefinition()->getLocation(),
2547 diag::note_previous_definition);
2551 // Create the class template partial specialization declaration.
2552 ClassTemplateSpecializationDecl *InstD
2553 = ClassTemplateSpecializationDecl::Create(SemaRef.Context,
2563 // Add this partial specialization to the set of class template partial
2566 InstClassTemplate->AddSpecialization(InstD, InsertPos);
2568 // Substitute the nested name specifier, if any.
2569 if (SubstQualifier(D, InstD))
2572 // Build the canonical type that describes the converted template
2573 // arguments of the class template explicit specialization.
2574 QualType CanonType = SemaRef.Context.getTemplateSpecializationType(
2575 TemplateName(InstClassTemplate), Converted.data(), Converted.size(),
2576 SemaRef.Context.getRecordType(InstD));
2578 // Build the fully-sugared type for this class template
2579 // specialization as the user wrote in the specialization
2580 // itself. This means that we'll pretty-print the type retrieved
2581 // from the specialization's declaration the way that the user
2582 // actually wrote the specialization, rather than formatting the
2583 // name based on the "canonical" representation used to store the
2584 // template arguments in the specialization.
2585 TypeSourceInfo *WrittenTy = SemaRef.Context.getTemplateSpecializationTypeInfo(
2586 TemplateName(InstClassTemplate), D->getLocation(), InstTemplateArgs,
2589 InstD->setAccess(D->getAccess());
2590 InstD->setInstantiationOfMemberClass(D, TSK_ImplicitInstantiation);
2591 InstD->setSpecializationKind(D->getSpecializationKind());
2592 InstD->setTypeAsWritten(WrittenTy);
2593 InstD->setExternLoc(D->getExternLoc());
2594 InstD->setTemplateKeywordLoc(D->getTemplateKeywordLoc());
2596 Owner->addDecl(InstD);
2598 // Instantiate the members of the class-scope explicit specialization eagerly.
2599 // We don't have support for lazy instantiation of an explicit specialization
2600 // yet, and MSVC eagerly instantiates in this case.
2601 if (D->isThisDeclarationADefinition() &&
2602 SemaRef.InstantiateClass(D->getLocation(), InstD, D, TemplateArgs,
2603 TSK_ImplicitInstantiation,
2610 Decl *TemplateDeclInstantiator::VisitVarTemplateSpecializationDecl(
2611 VarTemplateSpecializationDecl *D) {
2613 TemplateArgumentListInfo VarTemplateArgsInfo;
2614 VarTemplateDecl *VarTemplate = D->getSpecializedTemplate();
2615 assert(VarTemplate &&
2616 "A template specialization without specialized template?");
2618 // Substitute the current template arguments.
2619 const TemplateArgumentListInfo &TemplateArgsInfo = D->getTemplateArgsInfo();
2620 VarTemplateArgsInfo.setLAngleLoc(TemplateArgsInfo.getLAngleLoc());
2621 VarTemplateArgsInfo.setRAngleLoc(TemplateArgsInfo.getRAngleLoc());
2623 if (SemaRef.Subst(TemplateArgsInfo.getArgumentArray(),
2624 TemplateArgsInfo.size(), VarTemplateArgsInfo, TemplateArgs))
2627 // Check that the template argument list is well-formed for this template.
2628 SmallVector<TemplateArgument, 4> Converted;
2629 if (SemaRef.CheckTemplateArgumentList(
2630 VarTemplate, VarTemplate->getLocStart(),
2631 const_cast<TemplateArgumentListInfo &>(VarTemplateArgsInfo), false,
2635 // Find the variable template specialization declaration that
2636 // corresponds to these arguments.
2637 void *InsertPos = nullptr;
2638 if (VarTemplateSpecializationDecl *VarSpec = VarTemplate->findSpecialization(
2639 Converted, InsertPos))
2640 // If we already have a variable template specialization, return it.
2643 return VisitVarTemplateSpecializationDecl(VarTemplate, D, InsertPos,
2644 VarTemplateArgsInfo, Converted);
2647 Decl *TemplateDeclInstantiator::VisitVarTemplateSpecializationDecl(
2648 VarTemplateDecl *VarTemplate, VarDecl *D, void *InsertPos,
2649 const TemplateArgumentListInfo &TemplateArgsInfo,
2650 ArrayRef<TemplateArgument> Converted) {
2652 // If this is the variable for an anonymous struct or union,
2653 // instantiate the anonymous struct/union type first.
2654 if (const RecordType *RecordTy = D->getType()->getAs<RecordType>())
2655 if (RecordTy->getDecl()->isAnonymousStructOrUnion())
2656 if (!VisitCXXRecordDecl(cast<CXXRecordDecl>(RecordTy->getDecl())))
2659 // Do substitution on the type of the declaration
2660 TypeSourceInfo *DI =
2661 SemaRef.SubstType(D->getTypeSourceInfo(), TemplateArgs,
2662 D->getTypeSpecStartLoc(), D->getDeclName());
2666 if (DI->getType()->isFunctionType()) {
2667 SemaRef.Diag(D->getLocation(), diag::err_variable_instantiates_to_function)
2668 << D->isStaticDataMember() << DI->getType();
2672 // Build the instantiated declaration
2673 VarTemplateSpecializationDecl *Var = VarTemplateSpecializationDecl::Create(
2674 SemaRef.Context, Owner, D->getInnerLocStart(), D->getLocation(),
2675 VarTemplate, DI->getType(), DI, D->getStorageClass(), Converted.data(),
2677 Var->setTemplateArgsInfo(TemplateArgsInfo);
2679 VarTemplate->AddSpecialization(Var, InsertPos);
2681 // Substitute the nested name specifier, if any.
2682 if (SubstQualifier(D, Var))
2685 SemaRef.BuildVariableInstantiation(Var, D, TemplateArgs, LateAttrs,
2686 Owner, StartingScope);
2691 Decl *TemplateDeclInstantiator::VisitObjCAtDefsFieldDecl(ObjCAtDefsFieldDecl *D) {
2692 llvm_unreachable("@defs is not supported in Objective-C++");
2695 Decl *TemplateDeclInstantiator::VisitFriendTemplateDecl(FriendTemplateDecl *D) {
2696 // FIXME: We need to be able to instantiate FriendTemplateDecls.
2697 unsigned DiagID = SemaRef.getDiagnostics().getCustomDiagID(
2698 DiagnosticsEngine::Error,
2699 "cannot instantiate %0 yet");
2700 SemaRef.Diag(D->getLocation(), DiagID)
2701 << D->getDeclKindName();
2706 Decl *TemplateDeclInstantiator::VisitDecl(Decl *D) {
2707 llvm_unreachable("Unexpected decl");
2710 Decl *Sema::SubstDecl(Decl *D, DeclContext *Owner,
2711 const MultiLevelTemplateArgumentList &TemplateArgs) {
2712 TemplateDeclInstantiator Instantiator(*this, Owner, TemplateArgs);
2713 if (D->isInvalidDecl())
2716 return Instantiator.Visit(D);
2719 /// \brief Instantiates a nested template parameter list in the current
2720 /// instantiation context.
2722 /// \param L The parameter list to instantiate
2724 /// \returns NULL if there was an error
2725 TemplateParameterList *
2726 TemplateDeclInstantiator::SubstTemplateParams(TemplateParameterList *L) {
2727 // Get errors for all the parameters before bailing out.
2728 bool Invalid = false;
2730 unsigned N = L->size();
2731 typedef SmallVector<NamedDecl *, 8> ParamVector;
2734 for (TemplateParameterList::iterator PI = L->begin(), PE = L->end();
2736 NamedDecl *D = cast_or_null<NamedDecl>(Visit(*PI));
2737 Params.push_back(D);
2738 Invalid = Invalid || !D || D->isInvalidDecl();
2741 // Clean up if we had an error.
2745 TemplateParameterList *InstL
2746 = TemplateParameterList::Create(SemaRef.Context, L->getTemplateLoc(),
2747 L->getLAngleLoc(), &Params.front(), N,
2752 /// \brief Instantiate the declaration of a class template partial
2755 /// \param ClassTemplate the (instantiated) class template that is partially
2756 // specialized by the instantiation of \p PartialSpec.
2758 /// \param PartialSpec the (uninstantiated) class template partial
2759 /// specialization that we are instantiating.
2761 /// \returns The instantiated partial specialization, if successful; otherwise,
2762 /// NULL to indicate an error.
2763 ClassTemplatePartialSpecializationDecl *
2764 TemplateDeclInstantiator::InstantiateClassTemplatePartialSpecialization(
2765 ClassTemplateDecl *ClassTemplate,
2766 ClassTemplatePartialSpecializationDecl *PartialSpec) {
2767 // Create a local instantiation scope for this class template partial
2768 // specialization, which will contain the instantiations of the template
2770 LocalInstantiationScope Scope(SemaRef);
2772 // Substitute into the template parameters of the class template partial
2774 TemplateParameterList *TempParams = PartialSpec->getTemplateParameters();
2775 TemplateParameterList *InstParams = SubstTemplateParams(TempParams);
2779 // Substitute into the template arguments of the class template partial
2781 const ASTTemplateArgumentListInfo *TemplArgInfo
2782 = PartialSpec->getTemplateArgsAsWritten();
2783 TemplateArgumentListInfo InstTemplateArgs(TemplArgInfo->LAngleLoc,
2784 TemplArgInfo->RAngleLoc);
2785 if (SemaRef.Subst(TemplArgInfo->getTemplateArgs(),
2786 TemplArgInfo->NumTemplateArgs,
2787 InstTemplateArgs, TemplateArgs))
2790 // Check that the template argument list is well-formed for this
2792 SmallVector<TemplateArgument, 4> Converted;
2793 if (SemaRef.CheckTemplateArgumentList(ClassTemplate,
2794 PartialSpec->getLocation(),
2800 // Figure out where to insert this class template partial specialization
2801 // in the member template's set of class template partial specializations.
2802 void *InsertPos = nullptr;
2803 ClassTemplateSpecializationDecl *PrevDecl
2804 = ClassTemplate->findPartialSpecialization(Converted, InsertPos);
2806 // Build the canonical type that describes the converted template
2807 // arguments of the class template partial specialization.
2809 = SemaRef.Context.getTemplateSpecializationType(TemplateName(ClassTemplate),
2813 // Build the fully-sugared type for this class template
2814 // specialization as the user wrote in the specialization
2815 // itself. This means that we'll pretty-print the type retrieved
2816 // from the specialization's declaration the way that the user
2817 // actually wrote the specialization, rather than formatting the
2818 // name based on the "canonical" representation used to store the
2819 // template arguments in the specialization.
2820 TypeSourceInfo *WrittenTy
2821 = SemaRef.Context.getTemplateSpecializationTypeInfo(
2822 TemplateName(ClassTemplate),
2823 PartialSpec->getLocation(),
2828 // We've already seen a partial specialization with the same template
2829 // parameters and template arguments. This can happen, for example, when
2830 // substituting the outer template arguments ends up causing two
2831 // class template partial specializations of a member class template
2832 // to have identical forms, e.g.,
2834 // template<typename T, typename U>
2836 // template<typename X, typename Y> struct Inner;
2837 // template<typename Y> struct Inner<T, Y>;
2838 // template<typename Y> struct Inner<U, Y>;
2841 // Outer<int, int> outer; // error: the partial specializations of Inner
2842 // // have the same signature.
2843 SemaRef.Diag(PartialSpec->getLocation(), diag::err_partial_spec_redeclared)
2844 << WrittenTy->getType();
2845 SemaRef.Diag(PrevDecl->getLocation(), diag::note_prev_partial_spec_here)
2846 << SemaRef.Context.getTypeDeclType(PrevDecl);
2851 // Create the class template partial specialization declaration.
2852 ClassTemplatePartialSpecializationDecl *InstPartialSpec
2853 = ClassTemplatePartialSpecializationDecl::Create(SemaRef.Context,
2854 PartialSpec->getTagKind(),
2856 PartialSpec->getLocStart(),
2857 PartialSpec->getLocation(),
2865 // Substitute the nested name specifier, if any.
2866 if (SubstQualifier(PartialSpec, InstPartialSpec))
2869 InstPartialSpec->setInstantiatedFromMember(PartialSpec);
2870 InstPartialSpec->setTypeAsWritten(WrittenTy);
2872 // Add this partial specialization to the set of class template partial
2874 ClassTemplate->AddPartialSpecialization(InstPartialSpec,
2875 /*InsertPos=*/nullptr);
2876 return InstPartialSpec;
2879 /// \brief Instantiate the declaration of a variable template partial
2882 /// \param VarTemplate the (instantiated) variable template that is partially
2883 /// specialized by the instantiation of \p PartialSpec.
2885 /// \param PartialSpec the (uninstantiated) variable template partial
2886 /// specialization that we are instantiating.
2888 /// \returns The instantiated partial specialization, if successful; otherwise,
2889 /// NULL to indicate an error.
2890 VarTemplatePartialSpecializationDecl *
2891 TemplateDeclInstantiator::InstantiateVarTemplatePartialSpecialization(
2892 VarTemplateDecl *VarTemplate,
2893 VarTemplatePartialSpecializationDecl *PartialSpec) {
2894 // Create a local instantiation scope for this variable template partial
2895 // specialization, which will contain the instantiations of the template
2897 LocalInstantiationScope Scope(SemaRef);
2899 // Substitute into the template parameters of the variable template partial
2901 TemplateParameterList *TempParams = PartialSpec->getTemplateParameters();
2902 TemplateParameterList *InstParams = SubstTemplateParams(TempParams);
2906 // Substitute into the template arguments of the variable template partial
2908 const ASTTemplateArgumentListInfo *TemplArgInfo
2909 = PartialSpec->getTemplateArgsAsWritten();
2910 TemplateArgumentListInfo InstTemplateArgs(TemplArgInfo->LAngleLoc,
2911 TemplArgInfo->RAngleLoc);
2912 if (SemaRef.Subst(TemplArgInfo->getTemplateArgs(),
2913 TemplArgInfo->NumTemplateArgs,
2914 InstTemplateArgs, TemplateArgs))
2917 // Check that the template argument list is well-formed for this
2919 SmallVector<TemplateArgument, 4> Converted;
2920 if (SemaRef.CheckTemplateArgumentList(VarTemplate, PartialSpec->getLocation(),
2921 InstTemplateArgs, false, Converted))
2924 // Figure out where to insert this variable template partial specialization
2925 // in the member template's set of variable template partial specializations.
2926 void *InsertPos = nullptr;
2927 VarTemplateSpecializationDecl *PrevDecl =
2928 VarTemplate->findPartialSpecialization(Converted, InsertPos);
2930 // Build the canonical type that describes the converted template
2931 // arguments of the variable template partial specialization.
2932 QualType CanonType = SemaRef.Context.getTemplateSpecializationType(
2933 TemplateName(VarTemplate), Converted.data(), Converted.size());
2935 // Build the fully-sugared type for this variable template
2936 // specialization as the user wrote in the specialization
2937 // itself. This means that we'll pretty-print the type retrieved
2938 // from the specialization's declaration the way that the user
2939 // actually wrote the specialization, rather than formatting the
2940 // name based on the "canonical" representation used to store the
2941 // template arguments in the specialization.
2942 TypeSourceInfo *WrittenTy = SemaRef.Context.getTemplateSpecializationTypeInfo(
2943 TemplateName(VarTemplate), PartialSpec->getLocation(), InstTemplateArgs,
2947 // We've already seen a partial specialization with the same template
2948 // parameters and template arguments. This can happen, for example, when
2949 // substituting the outer template arguments ends up causing two
2950 // variable template partial specializations of a member variable template
2951 // to have identical forms, e.g.,
2953 // template<typename T, typename U>
2955 // template<typename X, typename Y> pair<X,Y> p;
2956 // template<typename Y> pair<T, Y> p;
2957 // template<typename Y> pair<U, Y> p;
2960 // Outer<int, int> outer; // error: the partial specializations of Inner
2961 // // have the same signature.
2962 SemaRef.Diag(PartialSpec->getLocation(),
2963 diag::err_var_partial_spec_redeclared)
2964 << WrittenTy->getType();
2965 SemaRef.Diag(PrevDecl->getLocation(),
2966 diag::note_var_prev_partial_spec_here);
2970 // Do substitution on the type of the declaration
2971 TypeSourceInfo *DI = SemaRef.SubstType(
2972 PartialSpec->getTypeSourceInfo(), TemplateArgs,
2973 PartialSpec->getTypeSpecStartLoc(), PartialSpec->getDeclName());
2977 if (DI->getType()->isFunctionType()) {
2978 SemaRef.Diag(PartialSpec->getLocation(),
2979 diag::err_variable_instantiates_to_function)
2980 << PartialSpec->isStaticDataMember() << DI->getType();
2984 // Create the variable template partial specialization declaration.
2985 VarTemplatePartialSpecializationDecl *InstPartialSpec =
2986 VarTemplatePartialSpecializationDecl::Create(
2987 SemaRef.Context, Owner, PartialSpec->getInnerLocStart(),
2988 PartialSpec->getLocation(), InstParams, VarTemplate, DI->getType(),
2989 DI, PartialSpec->getStorageClass(), Converted.data(),
2990 Converted.size(), InstTemplateArgs);
2992 // Substitute the nested name specifier, if any.
2993 if (SubstQualifier(PartialSpec, InstPartialSpec))
2996 InstPartialSpec->setInstantiatedFromMember(PartialSpec);
2997 InstPartialSpec->setTypeAsWritten(WrittenTy);
2999 // Add this partial specialization to the set of variable template partial
3000 // specializations. The instantiation of the initializer is not necessary.
3001 VarTemplate->AddPartialSpecialization(InstPartialSpec, /*InsertPos=*/nullptr);
3003 SemaRef.BuildVariableInstantiation(InstPartialSpec, PartialSpec, TemplateArgs,
3004 LateAttrs, Owner, StartingScope);
3006 return InstPartialSpec;
3010 TemplateDeclInstantiator::SubstFunctionType(FunctionDecl *D,
3011 SmallVectorImpl<ParmVarDecl *> &Params) {
3012 TypeSourceInfo *OldTInfo = D->getTypeSourceInfo();
3013 assert(OldTInfo && "substituting function without type source info");
3014 assert(Params.empty() && "parameter vector is non-empty at start");
3016 CXXRecordDecl *ThisContext = nullptr;
3017 unsigned ThisTypeQuals = 0;
3018 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(D)) {
3019 ThisContext = cast<CXXRecordDecl>(Owner);
3020 ThisTypeQuals = Method->getTypeQualifiers();
3023 TypeSourceInfo *NewTInfo
3024 = SemaRef.SubstFunctionDeclType(OldTInfo, TemplateArgs,
3025 D->getTypeSpecStartLoc(),
3027 ThisContext, ThisTypeQuals);
3031 TypeLoc OldTL = OldTInfo->getTypeLoc().IgnoreParens();
3032 if (FunctionProtoTypeLoc OldProtoLoc = OldTL.getAs<FunctionProtoTypeLoc>()) {
3033 if (NewTInfo != OldTInfo) {
3034 // Get parameters from the new type info.
3035 TypeLoc NewTL = NewTInfo->getTypeLoc().IgnoreParens();
3036 FunctionProtoTypeLoc NewProtoLoc = NewTL.castAs<FunctionProtoTypeLoc>();
3037 unsigned NewIdx = 0;
3038 for (unsigned OldIdx = 0, NumOldParams = OldProtoLoc.getNumParams();
3039 OldIdx != NumOldParams; ++OldIdx) {
3040 ParmVarDecl *OldParam = OldProtoLoc.getParam(OldIdx);
3041 LocalInstantiationScope *Scope = SemaRef.CurrentInstantiationScope;
3043 Optional<unsigned> NumArgumentsInExpansion;
3044 if (OldParam->isParameterPack())
3045 NumArgumentsInExpansion =
3046 SemaRef.getNumArgumentsInExpansion(OldParam->getType(),
3048 if (!NumArgumentsInExpansion) {
3049 // Simple case: normal parameter, or a parameter pack that's
3050 // instantiated to a (still-dependent) parameter pack.
3051 ParmVarDecl *NewParam = NewProtoLoc.getParam(NewIdx++);
3052 Params.push_back(NewParam);
3053 Scope->InstantiatedLocal(OldParam, NewParam);
3055 // Parameter pack expansion: make the instantiation an argument pack.
3056 Scope->MakeInstantiatedLocalArgPack(OldParam);
3057 for (unsigned I = 0; I != *NumArgumentsInExpansion; ++I) {
3058 ParmVarDecl *NewParam = NewProtoLoc.getParam(NewIdx++);
3059 Params.push_back(NewParam);
3060 Scope->InstantiatedLocalPackArg(OldParam, NewParam);
3065 // The function type itself was not dependent and therefore no
3066 // substitution occurred. However, we still need to instantiate
3067 // the function parameters themselves.
3068 const FunctionProtoType *OldProto =
3069 cast<FunctionProtoType>(OldProtoLoc.getType());
3070 for (unsigned i = 0, i_end = OldProtoLoc.getNumParams(); i != i_end;
3072 ParmVarDecl *OldParam = OldProtoLoc.getParam(i);
3074 Params.push_back(SemaRef.BuildParmVarDeclForTypedef(
3075 D, D->getLocation(), OldProto->getParamType(i)));
3080 cast_or_null<ParmVarDecl>(VisitParmVarDecl(OldParam));
3083 Params.push_back(Parm);
3087 // If the type of this function, after ignoring parentheses, is not
3088 // *directly* a function type, then we're instantiating a function that
3089 // was declared via a typedef or with attributes, e.g.,
3091 // typedef int functype(int, int);
3093 // int __cdecl meth(int, int);
3095 // In this case, we'll just go instantiate the ParmVarDecls that we
3096 // synthesized in the method declaration.
3097 SmallVector<QualType, 4> ParamTypes;
3098 if (SemaRef.SubstParmTypes(D->getLocation(), D->param_begin(),
3099 D->getNumParams(), TemplateArgs, ParamTypes,
3107 /// Introduce the instantiated function parameters into the local
3108 /// instantiation scope, and set the parameter names to those used
3109 /// in the template.
3110 static bool addInstantiatedParametersToScope(Sema &S, FunctionDecl *Function,
3111 const FunctionDecl *PatternDecl,
3112 LocalInstantiationScope &Scope,
3113 const MultiLevelTemplateArgumentList &TemplateArgs) {
3114 unsigned FParamIdx = 0;
3115 for (unsigned I = 0, N = PatternDecl->getNumParams(); I != N; ++I) {
3116 const ParmVarDecl *PatternParam = PatternDecl->getParamDecl(I);
3117 if (!PatternParam->isParameterPack()) {
3118 // Simple case: not a parameter pack.
3119 assert(FParamIdx < Function->getNumParams());
3120 ParmVarDecl *FunctionParam = Function->getParamDecl(FParamIdx);
3121 FunctionParam->setDeclName(PatternParam->getDeclName());
3122 // If the parameter's type is not dependent, update it to match the type
3123 // in the pattern. They can differ in top-level cv-qualifiers, and we want
3124 // the pattern's type here. If the type is dependent, they can't differ,
3125 // per core issue 1668. Substitute into the type from the pattern, in case
3126 // it's instantiation-dependent.
3127 // FIXME: Updating the type to work around this is at best fragile.
3128 if (!PatternDecl->getType()->isDependentType()) {
3129 QualType T = S.SubstType(PatternParam->getType(), TemplateArgs,
3130 FunctionParam->getLocation(),
3131 FunctionParam->getDeclName());
3134 FunctionParam->setType(T);
3137 Scope.InstantiatedLocal(PatternParam, FunctionParam);
3142 // Expand the parameter pack.
3143 Scope.MakeInstantiatedLocalArgPack(PatternParam);
3144 Optional<unsigned> NumArgumentsInExpansion
3145 = S.getNumArgumentsInExpansion(PatternParam->getType(), TemplateArgs);
3146 assert(NumArgumentsInExpansion &&
3147 "should only be called when all template arguments are known");
3148 QualType PatternType =
3149 PatternParam->getType()->castAs<PackExpansionType>()->getPattern();
3150 for (unsigned Arg = 0; Arg < *NumArgumentsInExpansion; ++Arg) {
3151 ParmVarDecl *FunctionParam = Function->getParamDecl(FParamIdx);
3152 FunctionParam->setDeclName(PatternParam->getDeclName());
3153 if (!PatternDecl->getType()->isDependentType()) {
3154 Sema::ArgumentPackSubstitutionIndexRAII SubstIndex(S, Arg);
3155 QualType T = S.SubstType(PatternType, TemplateArgs,
3156 FunctionParam->getLocation(),
3157 FunctionParam->getDeclName());
3160 FunctionParam->setType(T);
3163 Scope.InstantiatedLocalPackArg(PatternParam, FunctionParam);
3171 void Sema::InstantiateExceptionSpec(SourceLocation PointOfInstantiation,
3172 FunctionDecl *Decl) {
3173 const FunctionProtoType *Proto = Decl->getType()->castAs<FunctionProtoType>();
3174 if (Proto->getExceptionSpecType() != EST_Uninstantiated)
3177 InstantiatingTemplate Inst(*this, PointOfInstantiation, Decl,
3178 InstantiatingTemplate::ExceptionSpecification());
3179 if (Inst.isInvalid()) {
3180 // We hit the instantiation depth limit. Clear the exception specification
3181 // so that our callers don't have to cope with EST_Uninstantiated.
3182 UpdateExceptionSpec(Decl, EST_None);
3186 // Enter the scope of this instantiation. We don't use
3187 // PushDeclContext because we don't have a scope.
3188 Sema::ContextRAII savedContext(*this, Decl);
3189 LocalInstantiationScope Scope(*this);
3191 MultiLevelTemplateArgumentList TemplateArgs =
3192 getTemplateInstantiationArgs(Decl, nullptr, /*RelativeToPrimary*/true);
3194 FunctionDecl *Template = Proto->getExceptionSpecTemplate();
3195 if (addInstantiatedParametersToScope(*this, Decl, Template, Scope,
3197 UpdateExceptionSpec(Decl, EST_None);
3201 SubstExceptionSpec(Decl, Template->getType()->castAs<FunctionProtoType>(),
3205 /// \brief Initializes the common fields of an instantiation function
3206 /// declaration (New) from the corresponding fields of its template (Tmpl).
3208 /// \returns true if there was an error
3210 TemplateDeclInstantiator::InitFunctionInstantiation(FunctionDecl *New,
3211 FunctionDecl *Tmpl) {
3212 if (Tmpl->isDeleted())
3213 New->setDeletedAsWritten();
3215 // Forward the mangling number from the template to the instantiated decl.
3216 SemaRef.Context.setManglingNumber(New,
3217 SemaRef.Context.getManglingNumber(Tmpl));
3219 // If we are performing substituting explicitly-specified template arguments
3220 // or deduced template arguments into a function template and we reach this
3221 // point, we are now past the point where SFINAE applies and have committed
3222 // to keeping the new function template specialization. We therefore
3223 // convert the active template instantiation for the function template
3224 // into a template instantiation for this specific function template
3225 // specialization, which is not a SFINAE context, so that we diagnose any
3226 // further errors in the declaration itself.
3227 typedef Sema::ActiveTemplateInstantiation ActiveInstType;
3228 ActiveInstType &ActiveInst = SemaRef.ActiveTemplateInstantiations.back();
3229 if (ActiveInst.Kind == ActiveInstType::ExplicitTemplateArgumentSubstitution ||
3230 ActiveInst.Kind == ActiveInstType::DeducedTemplateArgumentSubstitution) {
3231 if (FunctionTemplateDecl *FunTmpl
3232 = dyn_cast<FunctionTemplateDecl>(ActiveInst.Entity)) {
3233 assert(FunTmpl->getTemplatedDecl() == Tmpl &&
3234 "Deduction from the wrong function template?");
3236 ActiveInst.Kind = ActiveInstType::TemplateInstantiation;
3237 ActiveInst.Entity = New;
3241 const FunctionProtoType *Proto = Tmpl->getType()->getAs<FunctionProtoType>();
3242 assert(Proto && "Function template without prototype?");
3244 if (Proto->hasExceptionSpec() || Proto->getNoReturnAttr()) {
3245 FunctionProtoType::ExtProtoInfo EPI = Proto->getExtProtoInfo();
3247 // DR1330: In C++11, defer instantiation of a non-trivial
3248 // exception specification.
3249 if (SemaRef.getLangOpts().CPlusPlus11 &&
3250 EPI.ExceptionSpec.Type != EST_None &&
3251 EPI.ExceptionSpec.Type != EST_DynamicNone &&
3252 EPI.ExceptionSpec.Type != EST_BasicNoexcept) {
3253 FunctionDecl *ExceptionSpecTemplate = Tmpl;
3254 if (EPI.ExceptionSpec.Type == EST_Uninstantiated)
3255 ExceptionSpecTemplate = EPI.ExceptionSpec.SourceTemplate;
3256 ExceptionSpecificationType NewEST = EST_Uninstantiated;
3257 if (EPI.ExceptionSpec.Type == EST_Unevaluated)
3258 NewEST = EST_Unevaluated;
3260 // Mark the function has having an uninstantiated exception specification.
3261 const FunctionProtoType *NewProto
3262 = New->getType()->getAs<FunctionProtoType>();
3263 assert(NewProto && "Template instantiation without function prototype?");
3264 EPI = NewProto->getExtProtoInfo();
3265 EPI.ExceptionSpec.Type = NewEST;
3266 EPI.ExceptionSpec.SourceDecl = New;
3267 EPI.ExceptionSpec.SourceTemplate = ExceptionSpecTemplate;
3268 New->setType(SemaRef.Context.getFunctionType(
3269 NewProto->getReturnType(), NewProto->getParamTypes(), EPI));
3271 SemaRef.SubstExceptionSpec(New, Proto, TemplateArgs);
3275 // Get the definition. Leaves the variable unchanged if undefined.
3276 const FunctionDecl *Definition = Tmpl;
3277 Tmpl->isDefined(Definition);
3279 SemaRef.InstantiateAttrs(TemplateArgs, Definition, New,
3280 LateAttrs, StartingScope);
3285 /// \brief Initializes common fields of an instantiated method
3286 /// declaration (New) from the corresponding fields of its template
3289 /// \returns true if there was an error
3291 TemplateDeclInstantiator::InitMethodInstantiation(CXXMethodDecl *New,
3292 CXXMethodDecl *Tmpl) {
3293 if (InitFunctionInstantiation(New, Tmpl))
3296 New->setAccess(Tmpl->getAccess());
3297 if (Tmpl->isVirtualAsWritten())
3298 New->setVirtualAsWritten(true);
3300 // FIXME: New needs a pointer to Tmpl
3304 /// \brief Instantiate the definition of the given function from its
3307 /// \param PointOfInstantiation the point at which the instantiation was
3308 /// required. Note that this is not precisely a "point of instantiation"
3309 /// for the function, but it's close.
3311 /// \param Function the already-instantiated declaration of a
3312 /// function template specialization or member function of a class template
3315 /// \param Recursive if true, recursively instantiates any functions that
3316 /// are required by this instantiation.
3318 /// \param DefinitionRequired if true, then we are performing an explicit
3319 /// instantiation where the body of the function is required. Complain if
3320 /// there is no such body.
3321 void Sema::InstantiateFunctionDefinition(SourceLocation PointOfInstantiation,
3322 FunctionDecl *Function,
3324 bool DefinitionRequired) {
3325 if (Function->isInvalidDecl() || Function->isDefined())
3328 // Never instantiate an explicit specialization except if it is a class scope
3329 // explicit specialization.
3330 if (Function->getTemplateSpecializationKind() == TSK_ExplicitSpecialization &&
3331 !Function->getClassScopeSpecializationPattern())
3334 // Find the function body that we'll be substituting.
3335 const FunctionDecl *PatternDecl = Function->getTemplateInstantiationPattern();
3336 assert(PatternDecl && "instantiating a non-template");
3338 Stmt *Pattern = PatternDecl->getBody(PatternDecl);
3339 assert(PatternDecl && "template definition is not a template");
3341 // Try to find a defaulted definition
3342 PatternDecl->isDefined(PatternDecl);
3344 assert(PatternDecl && "template definition is not a template");
3346 // Postpone late parsed template instantiations.
3347 if (PatternDecl->isLateTemplateParsed() &&
3348 !LateTemplateParser) {
3349 PendingInstantiations.push_back(
3350 std::make_pair(Function, PointOfInstantiation));
3354 // If we're performing recursive template instantiation, create our own
3355 // queue of pending implicit instantiations that we will instantiate later,
3356 // while we're still within our own instantiation context.
3357 // This has to happen before LateTemplateParser below is called, so that
3358 // it marks vtables used in late parsed templates as used.
3359 SavePendingLocalImplicitInstantiationsRAII
3360 SavedPendingLocalImplicitInstantiations(*this);
3361 SavePendingInstantiationsAndVTableUsesRAII
3362 SavePendingInstantiationsAndVTableUses(*this, /*Enabled=*/Recursive);
3364 // Call the LateTemplateParser callback if there is a need to late parse
3365 // a templated function definition.
3366 if (!Pattern && PatternDecl->isLateTemplateParsed() &&
3367 LateTemplateParser) {
3368 // FIXME: Optimize to allow individual templates to be deserialized.
3369 if (PatternDecl->isFromASTFile())
3370 ExternalSource->ReadLateParsedTemplates(LateParsedTemplateMap);
3372 LateParsedTemplate *LPT = LateParsedTemplateMap.lookup(PatternDecl);
3373 assert(LPT && "missing LateParsedTemplate");
3374 LateTemplateParser(OpaqueParser, *LPT);
3375 Pattern = PatternDecl->getBody(PatternDecl);
3378 if (!Pattern && !PatternDecl->isDefaulted()) {
3379 if (DefinitionRequired) {
3380 if (Function->getPrimaryTemplate())
3381 Diag(PointOfInstantiation,
3382 diag::err_explicit_instantiation_undefined_func_template)
3383 << Function->getPrimaryTemplate();
3385 Diag(PointOfInstantiation,
3386 diag::err_explicit_instantiation_undefined_member)
3387 << 1 << Function->getDeclName() << Function->getDeclContext();
3390 Diag(PatternDecl->getLocation(),
3391 diag::note_explicit_instantiation_here);
3392 Function->setInvalidDecl();
3393 } else if (Function->getTemplateSpecializationKind()
3394 == TSK_ExplicitInstantiationDefinition) {
3396 PendingInstantiations.push_back(
3397 std::make_pair(Function, PointOfInstantiation));
3403 // C++1y [temp.explicit]p10:
3404 // Except for inline functions, declarations with types deduced from their
3405 // initializer or return value, and class template specializations, other
3406 // explicit instantiation declarations have the effect of suppressing the
3407 // implicit instantiation of the entity to which they refer.
3408 if (Function->getTemplateSpecializationKind() ==
3409 TSK_ExplicitInstantiationDeclaration &&
3410 !PatternDecl->isInlined() &&
3411 !PatternDecl->getReturnType()->getContainedAutoType())
3414 if (PatternDecl->isInlined()) {
3415 // Function, and all later redeclarations of it (from imported modules,
3416 // for instance), are now implicitly inline.
3417 for (auto *D = Function->getMostRecentDecl(); /**/;
3418 D = D->getPreviousDecl()) {
3419 D->setImplicitlyInline();
3425 InstantiatingTemplate Inst(*this, PointOfInstantiation, Function);
3426 if (Inst.isInvalid())
3429 // Copy the inner loc start from the pattern.
3430 Function->setInnerLocStart(PatternDecl->getInnerLocStart());
3432 EnterExpressionEvaluationContext EvalContext(*this,
3433 Sema::PotentiallyEvaluated);
3435 // Introduce a new scope where local variable instantiations will be
3436 // recorded, unless we're actually a member function within a local
3437 // class, in which case we need to merge our results with the parent
3438 // scope (of the enclosing function).
3439 bool MergeWithParentScope = false;
3440 if (CXXRecordDecl *Rec = dyn_cast<CXXRecordDecl>(Function->getDeclContext()))
3441 MergeWithParentScope = Rec->isLocalClass();
3443 LocalInstantiationScope Scope(*this, MergeWithParentScope);
3445 if (PatternDecl->isDefaulted())
3446 SetDeclDefaulted(Function, PatternDecl->getLocation());
3448 MultiLevelTemplateArgumentList TemplateArgs =
3449 getTemplateInstantiationArgs(Function, nullptr, false, PatternDecl);
3451 // Substitute into the qualifier; we can get a substitution failure here
3452 // through evil use of alias templates.
3453 // FIXME: Is CurContext correct for this? Should we go to the (instantiation
3454 // of the) lexical context of the pattern?
3455 SubstQualifier(*this, PatternDecl, Function, TemplateArgs);
3457 ActOnStartOfFunctionDef(nullptr, Function);
3459 // Enter the scope of this instantiation. We don't use
3460 // PushDeclContext because we don't have a scope.
3461 Sema::ContextRAII savedContext(*this, Function);
3463 if (addInstantiatedParametersToScope(*this, Function, PatternDecl, Scope,
3467 // If this is a constructor, instantiate the member initializers.
3468 if (const CXXConstructorDecl *Ctor =
3469 dyn_cast<CXXConstructorDecl>(PatternDecl)) {
3470 InstantiateMemInitializers(cast<CXXConstructorDecl>(Function), Ctor,
3474 // Instantiate the function body.
3475 StmtResult Body = SubstStmt(Pattern, TemplateArgs);
3477 if (Body.isInvalid())
3478 Function->setInvalidDecl();
3480 ActOnFinishFunctionBody(Function, Body.get(),
3481 /*IsInstantiation=*/true);
3483 PerformDependentDiagnostics(PatternDecl, TemplateArgs);
3485 if (auto *Listener = getASTMutationListener())
3486 Listener->FunctionDefinitionInstantiated(Function);
3491 DeclGroupRef DG(Function);
3492 Consumer.HandleTopLevelDecl(DG);
3494 // This class may have local implicit instantiations that need to be
3495 // instantiation within this scope.
3496 PerformPendingInstantiations(/*LocalOnly=*/true);
3500 // Define any pending vtables.
3501 DefineUsedVTables();
3503 // Instantiate any pending implicit instantiations found during the
3504 // instantiation of this template.
3505 PerformPendingInstantiations();
3507 // PendingInstantiations and VTableUses are restored through
3508 // SavePendingInstantiationsAndVTableUses's destructor.
3512 VarTemplateSpecializationDecl *Sema::BuildVarTemplateInstantiation(
3513 VarTemplateDecl *VarTemplate, VarDecl *FromVar,
3514 const TemplateArgumentList &TemplateArgList,
3515 const TemplateArgumentListInfo &TemplateArgsInfo,
3516 SmallVectorImpl<TemplateArgument> &Converted,
3517 SourceLocation PointOfInstantiation, void *InsertPos,
3518 LateInstantiatedAttrVec *LateAttrs,
3519 LocalInstantiationScope *StartingScope) {
3520 if (FromVar->isInvalidDecl())
3523 InstantiatingTemplate Inst(*this, PointOfInstantiation, FromVar);
3524 if (Inst.isInvalid())
3527 MultiLevelTemplateArgumentList TemplateArgLists;
3528 TemplateArgLists.addOuterTemplateArguments(&TemplateArgList);
3530 // Instantiate the first declaration of the variable template: for a partial
3531 // specialization of a static data member template, the first declaration may
3532 // or may not be the declaration in the class; if it's in the class, we want
3533 // to instantiate a member in the class (a declaration), and if it's outside,
3534 // we want to instantiate a definition.
3536 // If we're instantiating an explicitly-specialized member template or member
3537 // partial specialization, don't do this. The member specialization completely
3538 // replaces the original declaration in this case.
3539 bool IsMemberSpec = false;
3540 if (VarTemplatePartialSpecializationDecl *PartialSpec =
3541 dyn_cast<VarTemplatePartialSpecializationDecl>(FromVar))
3542 IsMemberSpec = PartialSpec->isMemberSpecialization();
3543 else if (VarTemplateDecl *FromTemplate = FromVar->getDescribedVarTemplate())
3544 IsMemberSpec = FromTemplate->isMemberSpecialization();
3546 FromVar = FromVar->getFirstDecl();
3548 MultiLevelTemplateArgumentList MultiLevelList(TemplateArgList);
3549 TemplateDeclInstantiator Instantiator(*this, FromVar->getDeclContext(),
3552 // TODO: Set LateAttrs and StartingScope ...
3554 return cast_or_null<VarTemplateSpecializationDecl>(
3555 Instantiator.VisitVarTemplateSpecializationDecl(
3556 VarTemplate, FromVar, InsertPos, TemplateArgsInfo, Converted));
3559 /// \brief Instantiates a variable template specialization by completing it
3560 /// with appropriate type information and initializer.
3561 VarTemplateSpecializationDecl *Sema::CompleteVarTemplateSpecializationDecl(
3562 VarTemplateSpecializationDecl *VarSpec, VarDecl *PatternDecl,
3563 const MultiLevelTemplateArgumentList &TemplateArgs) {
3565 // Do substitution on the type of the declaration
3566 TypeSourceInfo *DI =
3567 SubstType(PatternDecl->getTypeSourceInfo(), TemplateArgs,
3568 PatternDecl->getTypeSpecStartLoc(), PatternDecl->getDeclName());
3572 // Update the type of this variable template specialization.
3573 VarSpec->setType(DI->getType());
3575 // Instantiate the initializer.
3576 InstantiateVariableInitializer(VarSpec, PatternDecl, TemplateArgs);
3581 /// BuildVariableInstantiation - Used after a new variable has been created.
3582 /// Sets basic variable data and decides whether to postpone the
3583 /// variable instantiation.
3584 void Sema::BuildVariableInstantiation(
3585 VarDecl *NewVar, VarDecl *OldVar,
3586 const MultiLevelTemplateArgumentList &TemplateArgs,
3587 LateInstantiatedAttrVec *LateAttrs, DeclContext *Owner,
3588 LocalInstantiationScope *StartingScope,
3589 bool InstantiatingVarTemplate) {
3591 // If we are instantiating a local extern declaration, the
3592 // instantiation belongs lexically to the containing function.
3593 // If we are instantiating a static data member defined
3594 // out-of-line, the instantiation will have the same lexical
3595 // context (which will be a namespace scope) as the template.
3596 if (OldVar->isLocalExternDecl()) {
3597 NewVar->setLocalExternDecl();
3598 NewVar->setLexicalDeclContext(Owner);
3599 } else if (OldVar->isOutOfLine())
3600 NewVar->setLexicalDeclContext(OldVar->getLexicalDeclContext());
3601 NewVar->setTSCSpec(OldVar->getTSCSpec());
3602 NewVar->setInitStyle(OldVar->getInitStyle());
3603 NewVar->setCXXForRangeDecl(OldVar->isCXXForRangeDecl());
3604 NewVar->setConstexpr(OldVar->isConstexpr());
3605 NewVar->setInitCapture(OldVar->isInitCapture());
3606 NewVar->setPreviousDeclInSameBlockScope(
3607 OldVar->isPreviousDeclInSameBlockScope());
3608 NewVar->setAccess(OldVar->getAccess());
3610 if (!OldVar->isStaticDataMember()) {
3611 if (OldVar->isUsed(false))
3612 NewVar->setIsUsed();
3613 NewVar->setReferenced(OldVar->isReferenced());
3616 // See if the old variable had a type-specifier that defined an anonymous tag.
3617 // If it did, mark the new variable as being the declarator for the new
3619 if (const TagType *OldTagType = OldVar->getType()->getAs<TagType>()) {
3620 TagDecl *OldTag = OldTagType->getDecl();
3621 if (OldTag->getDeclaratorForAnonDecl() == OldVar) {
3622 TagDecl *NewTag = NewVar->getType()->castAs<TagType>()->getDecl();
3623 assert(!NewTag->hasNameForLinkage() &&
3624 !NewTag->hasDeclaratorForAnonDecl());
3625 NewTag->setDeclaratorForAnonDecl(NewVar);
3629 InstantiateAttrs(TemplateArgs, OldVar, NewVar, LateAttrs, StartingScope);
3631 LookupResult Previous(
3632 *this, NewVar->getDeclName(), NewVar->getLocation(),
3633 NewVar->isLocalExternDecl() ? Sema::LookupRedeclarationWithLinkage
3634 : Sema::LookupOrdinaryName,
3635 Sema::ForRedeclaration);
3637 if (NewVar->isLocalExternDecl() && OldVar->getPreviousDecl() &&
3638 (!OldVar->getPreviousDecl()->getDeclContext()->isDependentContext() ||
3639 OldVar->getPreviousDecl()->getDeclContext()==OldVar->getDeclContext())) {
3640 // We have a previous declaration. Use that one, so we merge with the
3642 if (NamedDecl *NewPrev = FindInstantiatedDecl(
3643 NewVar->getLocation(), OldVar->getPreviousDecl(), TemplateArgs))
3644 Previous.addDecl(NewPrev);
3645 } else if (!isa<VarTemplateSpecializationDecl>(NewVar) &&
3646 OldVar->hasLinkage())
3647 LookupQualifiedName(Previous, NewVar->getDeclContext(), false);
3648 CheckVariableDeclaration(NewVar, Previous);
3650 if (!InstantiatingVarTemplate) {
3651 NewVar->getLexicalDeclContext()->addHiddenDecl(NewVar);
3652 if (!NewVar->isLocalExternDecl() || !NewVar->getPreviousDecl())
3653 NewVar->getDeclContext()->makeDeclVisibleInContext(NewVar);
3656 if (!OldVar->isOutOfLine()) {
3657 if (NewVar->getDeclContext()->isFunctionOrMethod())
3658 CurrentInstantiationScope->InstantiatedLocal(OldVar, NewVar);
3661 // Link instantiations of static data members back to the template from
3662 // which they were instantiated.
3663 if (NewVar->isStaticDataMember() && !InstantiatingVarTemplate)
3664 NewVar->setInstantiationOfStaticDataMember(OldVar,
3665 TSK_ImplicitInstantiation);
3667 // Forward the mangling number from the template to the instantiated decl.
3668 Context.setManglingNumber(NewVar, Context.getManglingNumber(OldVar));
3669 Context.setStaticLocalNumber(NewVar, Context.getStaticLocalNumber(OldVar));
3671 // Delay instantiation of the initializer for variable templates until a
3672 // definition of the variable is needed. We need it right away if the type
3674 if ((!isa<VarTemplateSpecializationDecl>(NewVar) &&
3675 !InstantiatingVarTemplate) ||
3676 NewVar->getType()->isUndeducedType())
3677 InstantiateVariableInitializer(NewVar, OldVar, TemplateArgs);
3679 // Diagnose unused local variables with dependent types, where the diagnostic
3680 // will have been deferred.
3681 if (!NewVar->isInvalidDecl() &&
3682 NewVar->getDeclContext()->isFunctionOrMethod() &&
3683 OldVar->getType()->isDependentType())
3684 DiagnoseUnusedDecl(NewVar);
3687 /// \brief Instantiate the initializer of a variable.
3688 void Sema::InstantiateVariableInitializer(
3689 VarDecl *Var, VarDecl *OldVar,
3690 const MultiLevelTemplateArgumentList &TemplateArgs) {
3692 if (Var->getAnyInitializer())
3693 // We already have an initializer in the class.
3696 if (OldVar->getInit()) {
3697 if (Var->isStaticDataMember() && !OldVar->isOutOfLine())
3698 PushExpressionEvaluationContext(Sema::ConstantEvaluated, OldVar);
3700 PushExpressionEvaluationContext(Sema::PotentiallyEvaluated, OldVar);
3702 // Instantiate the initializer.
3704 SubstInitializer(OldVar->getInit(), TemplateArgs,
3705 OldVar->getInitStyle() == VarDecl::CallInit);
3706 if (!Init.isInvalid()) {
3707 bool TypeMayContainAuto = true;
3708 Expr *InitExpr = Init.get();
3710 if (Var->hasAttr<DLLImportAttr>() &&
3712 !InitExpr->isConstantInitializer(getASTContext(), false))) {
3713 // Do not dynamically initialize dllimport variables.
3714 } else if (InitExpr) {
3715 bool DirectInit = OldVar->isDirectInit();
3716 AddInitializerToDecl(Var, InitExpr, DirectInit, TypeMayContainAuto);
3718 ActOnUninitializedDecl(Var, TypeMayContainAuto);
3720 // FIXME: Not too happy about invalidating the declaration
3721 // because of a bogus initializer.
3722 Var->setInvalidDecl();
3725 PopExpressionEvaluationContext();
3726 } else if ((!Var->isStaticDataMember() || Var->isOutOfLine()) &&
3727 !Var->isCXXForRangeDecl())
3728 ActOnUninitializedDecl(Var, false);
3731 /// \brief Instantiate the definition of the given variable from its
3734 /// \param PointOfInstantiation the point at which the instantiation was
3735 /// required. Note that this is not precisely a "point of instantiation"
3736 /// for the function, but it's close.
3738 /// \param Var the already-instantiated declaration of a static member
3739 /// variable of a class template specialization.
3741 /// \param Recursive if true, recursively instantiates any functions that
3742 /// are required by this instantiation.
3744 /// \param DefinitionRequired if true, then we are performing an explicit
3745 /// instantiation where an out-of-line definition of the member variable
3746 /// is required. Complain if there is no such definition.
3747 void Sema::InstantiateStaticDataMemberDefinition(
3748 SourceLocation PointOfInstantiation,
3751 bool DefinitionRequired) {
3752 InstantiateVariableDefinition(PointOfInstantiation, Var, Recursive,
3753 DefinitionRequired);
3756 void Sema::InstantiateVariableDefinition(SourceLocation PointOfInstantiation,
3757 VarDecl *Var, bool Recursive,
3758 bool DefinitionRequired) {
3759 if (Var->isInvalidDecl())
3762 VarTemplateSpecializationDecl *VarSpec =
3763 dyn_cast<VarTemplateSpecializationDecl>(Var);
3764 VarDecl *PatternDecl = nullptr, *Def = nullptr;
3765 MultiLevelTemplateArgumentList TemplateArgs =
3766 getTemplateInstantiationArgs(Var);
3769 // If this is a variable template specialization, make sure that it is
3770 // non-dependent, then find its instantiation pattern.
3771 bool InstantiationDependent = false;
3772 assert(!TemplateSpecializationType::anyDependentTemplateArguments(
3773 VarSpec->getTemplateArgsInfo(), InstantiationDependent) &&
3774 "Only instantiate variable template specializations that are "
3775 "not type-dependent");
3776 (void)InstantiationDependent;
3778 // Find the variable initialization that we'll be substituting. If the
3779 // pattern was instantiated from a member template, look back further to
3780 // find the real pattern.
3781 assert(VarSpec->getSpecializedTemplate() &&
3782 "Specialization without specialized template?");
3783 llvm::PointerUnion<VarTemplateDecl *,
3784 VarTemplatePartialSpecializationDecl *> PatternPtr =
3785 VarSpec->getSpecializedTemplateOrPartial();
3786 if (PatternPtr.is<VarTemplatePartialSpecializationDecl *>()) {
3787 VarTemplatePartialSpecializationDecl *Tmpl =
3788 PatternPtr.get<VarTemplatePartialSpecializationDecl *>();
3789 while (VarTemplatePartialSpecializationDecl *From =
3790 Tmpl->getInstantiatedFromMember()) {
3791 if (Tmpl->isMemberSpecialization())
3798 VarTemplateDecl *Tmpl = PatternPtr.get<VarTemplateDecl *>();
3799 while (VarTemplateDecl *From =
3800 Tmpl->getInstantiatedFromMemberTemplate()) {
3801 if (Tmpl->isMemberSpecialization())
3806 PatternDecl = Tmpl->getTemplatedDecl();
3809 // If this is a static data member template, there might be an
3810 // uninstantiated initializer on the declaration. If so, instantiate
3812 if (PatternDecl->isStaticDataMember() &&
3813 (PatternDecl = PatternDecl->getFirstDecl())->hasInit() &&
3815 // FIXME: Factor out the duplicated instantiation context setup/tear down
3817 InstantiatingTemplate Inst(*this, PointOfInstantiation, Var);
3818 if (Inst.isInvalid())
3821 // If we're performing recursive template instantiation, create our own
3822 // queue of pending implicit instantiations that we will instantiate
3823 // later, while we're still within our own instantiation context.
3824 SavePendingInstantiationsAndVTableUsesRAII
3825 SavePendingInstantiationsAndVTableUses(*this, /*Enabled=*/Recursive);
3827 LocalInstantiationScope Local(*this);
3829 // Enter the scope of this instantiation. We don't use
3830 // PushDeclContext because we don't have a scope.
3831 ContextRAII PreviousContext(*this, Var->getDeclContext());
3832 InstantiateVariableInitializer(Var, PatternDecl, TemplateArgs);
3833 PreviousContext.pop();
3835 // FIXME: Need to inform the ASTConsumer that we instantiated the
3838 // This variable may have local implicit instantiations that need to be
3839 // instantiated within this scope.
3840 PerformPendingInstantiations(/*LocalOnly=*/true);
3845 // Define any newly required vtables.
3846 DefineUsedVTables();
3848 // Instantiate any pending implicit instantiations found during the
3849 // instantiation of this template.
3850 PerformPendingInstantiations();
3852 // PendingInstantiations and VTableUses are restored through
3853 // SavePendingInstantiationsAndVTableUses's destructor.
3857 // Find actual definition
3858 Def = PatternDecl->getDefinition(getASTContext());
3860 // If this is a static data member, find its out-of-line definition.
3861 assert(Var->isStaticDataMember() && "not a static data member?");
3862 PatternDecl = Var->getInstantiatedFromStaticDataMember();
3864 assert(PatternDecl && "data member was not instantiated from a template?");
3865 assert(PatternDecl->isStaticDataMember() && "not a static data member?");
3866 Def = PatternDecl->getOutOfLineDefinition();
3869 // If we don't have a definition of the variable template, we won't perform
3870 // any instantiation. Rather, we rely on the user to instantiate this
3871 // definition (or provide a specialization for it) in another translation
3874 if (DefinitionRequired) {
3876 Diag(PointOfInstantiation,
3877 diag::err_explicit_instantiation_undefined_var_template) << Var;
3879 Diag(PointOfInstantiation,
3880 diag::err_explicit_instantiation_undefined_member)
3881 << 2 << Var->getDeclName() << Var->getDeclContext();
3882 Diag(PatternDecl->getLocation(),
3883 diag::note_explicit_instantiation_here);
3885 Var->setInvalidDecl();
3886 } else if (Var->getTemplateSpecializationKind()
3887 == TSK_ExplicitInstantiationDefinition) {
3888 PendingInstantiations.push_back(
3889 std::make_pair(Var, PointOfInstantiation));
3895 TemplateSpecializationKind TSK = Var->getTemplateSpecializationKind();
3897 // Never instantiate an explicit specialization.
3898 if (TSK == TSK_ExplicitSpecialization)
3901 // C++11 [temp.explicit]p10:
3902 // Except for inline functions, [...] explicit instantiation declarations
3903 // have the effect of suppressing the implicit instantiation of the entity
3904 // to which they refer.
3905 if (TSK == TSK_ExplicitInstantiationDeclaration)
3908 // Make sure to pass the instantiated variable to the consumer at the end.
3909 struct PassToConsumerRAII {
3910 ASTConsumer &Consumer;
3913 PassToConsumerRAII(ASTConsumer &Consumer, VarDecl *Var)
3914 : Consumer(Consumer), Var(Var) { }
3916 ~PassToConsumerRAII() {
3917 Consumer.HandleCXXStaticMemberVarInstantiation(Var);
3919 } PassToConsumerRAII(Consumer, Var);
3921 // If we already have a definition, we're done.
3922 if (VarDecl *Def = Var->getDefinition()) {
3923 // We may be explicitly instantiating something we've already implicitly
3925 Def->setTemplateSpecializationKind(Var->getTemplateSpecializationKind(),
3926 PointOfInstantiation);
3930 InstantiatingTemplate Inst(*this, PointOfInstantiation, Var);
3931 if (Inst.isInvalid())
3934 // If we're performing recursive template instantiation, create our own
3935 // queue of pending implicit instantiations that we will instantiate later,
3936 // while we're still within our own instantiation context.
3937 SavePendingLocalImplicitInstantiationsRAII
3938 SavedPendingLocalImplicitInstantiations(*this);
3939 SavePendingInstantiationsAndVTableUsesRAII
3940 SavePendingInstantiationsAndVTableUses(*this, /*Enabled=*/Recursive);
3942 // Enter the scope of this instantiation. We don't use
3943 // PushDeclContext because we don't have a scope.
3944 ContextRAII PreviousContext(*this, Var->getDeclContext());
3945 LocalInstantiationScope Local(*this);
3947 VarDecl *OldVar = Var;
3949 Var = cast_or_null<VarDecl>(SubstDecl(Def, Var->getDeclContext(),
3951 else if (Var->isStaticDataMember() &&
3952 Var->getLexicalDeclContext()->isRecord()) {
3953 // We need to instantiate the definition of a static data member template,
3954 // and all we have is the in-class declaration of it. Instantiate a separate
3955 // declaration of the definition.
3956 TemplateDeclInstantiator Instantiator(*this, Var->getDeclContext(),
3958 Var = cast_or_null<VarDecl>(Instantiator.VisitVarTemplateSpecializationDecl(
3959 VarSpec->getSpecializedTemplate(), Def, nullptr,
3960 VarSpec->getTemplateArgsInfo(), VarSpec->getTemplateArgs().asArray()));
3962 llvm::PointerUnion<VarTemplateDecl *,
3963 VarTemplatePartialSpecializationDecl *> PatternPtr =
3964 VarSpec->getSpecializedTemplateOrPartial();
3965 if (VarTemplatePartialSpecializationDecl *Partial =
3966 PatternPtr.dyn_cast<VarTemplatePartialSpecializationDecl *>())
3967 cast<VarTemplateSpecializationDecl>(Var)->setInstantiationOf(
3968 Partial, &VarSpec->getTemplateInstantiationArgs());
3970 // Merge the definition with the declaration.
3971 LookupResult R(*this, Var->getDeclName(), Var->getLocation(),
3972 LookupOrdinaryName, ForRedeclaration);
3974 MergeVarDecl(Var, R);
3976 // Attach the initializer.
3977 InstantiateVariableInitializer(Var, Def, TemplateArgs);
3980 // Complete the existing variable's definition with an appropriately
3981 // substituted type and initializer.
3982 Var = CompleteVarTemplateSpecializationDecl(VarSpec, Def, TemplateArgs);
3984 PreviousContext.pop();
3987 PassToConsumerRAII.Var = Var;
3988 Var->setTemplateSpecializationKind(OldVar->getTemplateSpecializationKind(),
3989 OldVar->getPointOfInstantiation());
3992 // This variable may have local implicit instantiations that need to be
3993 // instantiated within this scope.
3994 PerformPendingInstantiations(/*LocalOnly=*/true);
3999 // Define any newly required vtables.
4000 DefineUsedVTables();
4002 // Instantiate any pending implicit instantiations found during the
4003 // instantiation of this template.
4004 PerformPendingInstantiations();
4006 // PendingInstantiations and VTableUses are restored through
4007 // SavePendingInstantiationsAndVTableUses's destructor.
4012 Sema::InstantiateMemInitializers(CXXConstructorDecl *New,
4013 const CXXConstructorDecl *Tmpl,
4014 const MultiLevelTemplateArgumentList &TemplateArgs) {
4016 SmallVector<CXXCtorInitializer*, 4> NewInits;
4017 bool AnyErrors = Tmpl->isInvalidDecl();
4019 // Instantiate all the initializers.
4020 for (const auto *Init : Tmpl->inits()) {
4021 // Only instantiate written initializers, let Sema re-construct implicit
4023 if (!Init->isWritten())
4026 SourceLocation EllipsisLoc;
4028 if (Init->isPackExpansion()) {
4029 // This is a pack expansion. We should expand it now.
4030 TypeLoc BaseTL = Init->getTypeSourceInfo()->getTypeLoc();
4031 SmallVector<UnexpandedParameterPack, 4> Unexpanded;
4032 collectUnexpandedParameterPacks(BaseTL, Unexpanded);
4033 collectUnexpandedParameterPacks(Init->getInit(), Unexpanded);
4034 bool ShouldExpand = false;
4035 bool RetainExpansion = false;
4036 Optional<unsigned> NumExpansions;
4037 if (CheckParameterPacksForExpansion(Init->getEllipsisLoc(),
4038 BaseTL.getSourceRange(),
4040 TemplateArgs, ShouldExpand,
4044 New->setInvalidDecl();
4047 assert(ShouldExpand && "Partial instantiation of base initializer?");
4049 // Loop over all of the arguments in the argument pack(s),
4050 for (unsigned I = 0; I != *NumExpansions; ++I) {
4051 Sema::ArgumentPackSubstitutionIndexRAII SubstIndex(*this, I);
4053 // Instantiate the initializer.
4054 ExprResult TempInit = SubstInitializer(Init->getInit(), TemplateArgs,
4055 /*CXXDirectInit=*/true);
4056 if (TempInit.isInvalid()) {
4061 // Instantiate the base type.
4062 TypeSourceInfo *BaseTInfo = SubstType(Init->getTypeSourceInfo(),
4064 Init->getSourceLocation(),
4065 New->getDeclName());
4071 // Build the initializer.
4072 MemInitResult NewInit = BuildBaseInitializer(BaseTInfo->getType(),
4073 BaseTInfo, TempInit.get(),
4076 if (NewInit.isInvalid()) {
4081 NewInits.push_back(NewInit.get());
4087 // Instantiate the initializer.
4088 ExprResult TempInit = SubstInitializer(Init->getInit(), TemplateArgs,
4089 /*CXXDirectInit=*/true);
4090 if (TempInit.isInvalid()) {
4095 MemInitResult NewInit;
4096 if (Init->isDelegatingInitializer() || Init->isBaseInitializer()) {
4097 TypeSourceInfo *TInfo = SubstType(Init->getTypeSourceInfo(),
4099 Init->getSourceLocation(),
4100 New->getDeclName());
4103 New->setInvalidDecl();
4107 if (Init->isBaseInitializer())
4108 NewInit = BuildBaseInitializer(TInfo->getType(), TInfo, TempInit.get(),
4109 New->getParent(), EllipsisLoc);
4111 NewInit = BuildDelegatingInitializer(TInfo, TempInit.get(),
4112 cast<CXXRecordDecl>(CurContext->getParent()));
4113 } else if (Init->isMemberInitializer()) {
4114 FieldDecl *Member = cast_or_null<FieldDecl>(FindInstantiatedDecl(
4115 Init->getMemberLocation(),
4120 New->setInvalidDecl();
4124 NewInit = BuildMemberInitializer(Member, TempInit.get(),
4125 Init->getSourceLocation());
4126 } else if (Init->isIndirectMemberInitializer()) {
4127 IndirectFieldDecl *IndirectMember =
4128 cast_or_null<IndirectFieldDecl>(FindInstantiatedDecl(
4129 Init->getMemberLocation(),
4130 Init->getIndirectMember(), TemplateArgs));
4132 if (!IndirectMember) {
4134 New->setInvalidDecl();
4138 NewInit = BuildMemberInitializer(IndirectMember, TempInit.get(),
4139 Init->getSourceLocation());
4142 if (NewInit.isInvalid()) {
4144 New->setInvalidDecl();
4146 NewInits.push_back(NewInit.get());
4150 // Assign all the initializers to the new constructor.
4151 ActOnMemInitializers(New,
4152 /*FIXME: ColonLoc */
4158 // TODO: this could be templated if the various decl types used the
4159 // same method name.
4160 static bool isInstantiationOf(ClassTemplateDecl *Pattern,
4161 ClassTemplateDecl *Instance) {
4162 Pattern = Pattern->getCanonicalDecl();
4165 Instance = Instance->getCanonicalDecl();
4166 if (Pattern == Instance) return true;
4167 Instance = Instance->getInstantiatedFromMemberTemplate();
4173 static bool isInstantiationOf(FunctionTemplateDecl *Pattern,
4174 FunctionTemplateDecl *Instance) {
4175 Pattern = Pattern->getCanonicalDecl();
4178 Instance = Instance->getCanonicalDecl();
4179 if (Pattern == Instance) return true;
4180 Instance = Instance->getInstantiatedFromMemberTemplate();
4187 isInstantiationOf(ClassTemplatePartialSpecializationDecl *Pattern,
4188 ClassTemplatePartialSpecializationDecl *Instance) {
4190 = cast<ClassTemplatePartialSpecializationDecl>(Pattern->getCanonicalDecl());
4192 Instance = cast<ClassTemplatePartialSpecializationDecl>(
4193 Instance->getCanonicalDecl());
4194 if (Pattern == Instance)
4196 Instance = Instance->getInstantiatedFromMember();
4202 static bool isInstantiationOf(CXXRecordDecl *Pattern,
4203 CXXRecordDecl *Instance) {
4204 Pattern = Pattern->getCanonicalDecl();
4207 Instance = Instance->getCanonicalDecl();
4208 if (Pattern == Instance) return true;
4209 Instance = Instance->getInstantiatedFromMemberClass();
4215 static bool isInstantiationOf(FunctionDecl *Pattern,
4216 FunctionDecl *Instance) {
4217 Pattern = Pattern->getCanonicalDecl();
4220 Instance = Instance->getCanonicalDecl();
4221 if (Pattern == Instance) return true;
4222 Instance = Instance->getInstantiatedFromMemberFunction();
4228 static bool isInstantiationOf(EnumDecl *Pattern,
4229 EnumDecl *Instance) {
4230 Pattern = Pattern->getCanonicalDecl();
4233 Instance = Instance->getCanonicalDecl();
4234 if (Pattern == Instance) return true;
4235 Instance = Instance->getInstantiatedFromMemberEnum();
4241 static bool isInstantiationOf(UsingShadowDecl *Pattern,
4242 UsingShadowDecl *Instance,
4244 return declaresSameEntity(C.getInstantiatedFromUsingShadowDecl(Instance),
4248 static bool isInstantiationOf(UsingDecl *Pattern,
4249 UsingDecl *Instance,
4251 return declaresSameEntity(C.getInstantiatedFromUsingDecl(Instance), Pattern);
4254 static bool isInstantiationOf(UnresolvedUsingValueDecl *Pattern,
4255 UsingDecl *Instance,
4257 return declaresSameEntity(C.getInstantiatedFromUsingDecl(Instance), Pattern);
4260 static bool isInstantiationOf(UnresolvedUsingTypenameDecl *Pattern,
4261 UsingDecl *Instance,
4263 return declaresSameEntity(C.getInstantiatedFromUsingDecl(Instance), Pattern);
4266 static bool isInstantiationOfStaticDataMember(VarDecl *Pattern,
4267 VarDecl *Instance) {
4268 assert(Instance->isStaticDataMember());
4270 Pattern = Pattern->getCanonicalDecl();
4273 Instance = Instance->getCanonicalDecl();
4274 if (Pattern == Instance) return true;
4275 Instance = Instance->getInstantiatedFromStaticDataMember();
4281 // Other is the prospective instantiation
4282 // D is the prospective pattern
4283 static bool isInstantiationOf(ASTContext &Ctx, NamedDecl *D, Decl *Other) {
4284 if (D->getKind() != Other->getKind()) {
4285 if (UnresolvedUsingTypenameDecl *UUD
4286 = dyn_cast<UnresolvedUsingTypenameDecl>(D)) {
4287 if (UsingDecl *UD = dyn_cast<UsingDecl>(Other)) {
4288 return isInstantiationOf(UUD, UD, Ctx);
4292 if (UnresolvedUsingValueDecl *UUD
4293 = dyn_cast<UnresolvedUsingValueDecl>(D)) {
4294 if (UsingDecl *UD = dyn_cast<UsingDecl>(Other)) {
4295 return isInstantiationOf(UUD, UD, Ctx);
4302 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Other))
4303 return isInstantiationOf(cast<CXXRecordDecl>(D), Record);
4305 if (FunctionDecl *Function = dyn_cast<FunctionDecl>(Other))
4306 return isInstantiationOf(cast<FunctionDecl>(D), Function);
4308 if (EnumDecl *Enum = dyn_cast<EnumDecl>(Other))
4309 return isInstantiationOf(cast<EnumDecl>(D), Enum);
4311 if (VarDecl *Var = dyn_cast<VarDecl>(Other))
4312 if (Var->isStaticDataMember())
4313 return isInstantiationOfStaticDataMember(cast<VarDecl>(D), Var);
4315 if (ClassTemplateDecl *Temp = dyn_cast<ClassTemplateDecl>(Other))
4316 return isInstantiationOf(cast<ClassTemplateDecl>(D), Temp);
4318 if (FunctionTemplateDecl *Temp = dyn_cast<FunctionTemplateDecl>(Other))
4319 return isInstantiationOf(cast<FunctionTemplateDecl>(D), Temp);
4321 if (ClassTemplatePartialSpecializationDecl *PartialSpec
4322 = dyn_cast<ClassTemplatePartialSpecializationDecl>(Other))
4323 return isInstantiationOf(cast<ClassTemplatePartialSpecializationDecl>(D),
4326 if (FieldDecl *Field = dyn_cast<FieldDecl>(Other)) {
4327 if (!Field->getDeclName()) {
4328 // This is an unnamed field.
4329 return declaresSameEntity(Ctx.getInstantiatedFromUnnamedFieldDecl(Field),
4330 cast<FieldDecl>(D));
4334 if (UsingDecl *Using = dyn_cast<UsingDecl>(Other))
4335 return isInstantiationOf(cast<UsingDecl>(D), Using, Ctx);
4337 if (UsingShadowDecl *Shadow = dyn_cast<UsingShadowDecl>(Other))
4338 return isInstantiationOf(cast<UsingShadowDecl>(D), Shadow, Ctx);
4340 return D->getDeclName() && isa<NamedDecl>(Other) &&
4341 D->getDeclName() == cast<NamedDecl>(Other)->getDeclName();
4344 template<typename ForwardIterator>
4345 static NamedDecl *findInstantiationOf(ASTContext &Ctx,
4347 ForwardIterator first,
4348 ForwardIterator last) {
4349 for (; first != last; ++first)
4350 if (isInstantiationOf(Ctx, D, *first))
4351 return cast<NamedDecl>(*first);
4356 /// \brief Finds the instantiation of the given declaration context
4357 /// within the current instantiation.
4359 /// \returns NULL if there was an error
4360 DeclContext *Sema::FindInstantiatedContext(SourceLocation Loc, DeclContext* DC,
4361 const MultiLevelTemplateArgumentList &TemplateArgs) {
4362 if (NamedDecl *D = dyn_cast<NamedDecl>(DC)) {
4363 Decl* ID = FindInstantiatedDecl(Loc, D, TemplateArgs);
4364 return cast_or_null<DeclContext>(ID);
4368 /// \brief Find the instantiation of the given declaration within the
4369 /// current instantiation.
4371 /// This routine is intended to be used when \p D is a declaration
4372 /// referenced from within a template, that needs to mapped into the
4373 /// corresponding declaration within an instantiation. For example,
4377 /// template<typename T>
4380 /// KnownValue = sizeof(T)
4383 /// bool getKind() const { return KnownValue; }
4386 /// template struct X<int>;
4389 /// In the instantiation of <tt>X<int>::getKind()</tt>, we need to map the
4390 /// \p EnumConstantDecl for \p KnownValue (which refers to
4391 /// <tt>X<T>::<Kind>::KnownValue</tt>) to its instantiation
4392 /// (<tt>X<int>::<Kind>::KnownValue</tt>). \p FindInstantiatedDecl performs
4393 /// this mapping from within the instantiation of <tt>X<int></tt>.
4394 NamedDecl *Sema::FindInstantiatedDecl(SourceLocation Loc, NamedDecl *D,
4395 const MultiLevelTemplateArgumentList &TemplateArgs) {
4396 DeclContext *ParentDC = D->getDeclContext();
4397 // FIXME: Parmeters of pointer to functions (y below) that are themselves
4398 // parameters (p below) can have their ParentDC set to the translation-unit
4399 // - thus we can not consistently check if the ParentDC of such a parameter
4400 // is Dependent or/and a FunctionOrMethod.
4401 // For e.g. this code, during Template argument deduction tries to
4402 // find an instantiated decl for (T y) when the ParentDC for y is
4403 // the translation unit.
4404 // e.g. template <class T> void Foo(auto (*p)(T y) -> decltype(y())) {}
4405 // float baz(float(*)()) { return 0.0; }
4407 // The better fix here is perhaps to ensure that a ParmVarDecl, by the time
4408 // it gets here, always has a FunctionOrMethod as its ParentDC??
4410 // - as long as we have a ParmVarDecl whose parent is non-dependent and
4411 // whose type is not instantiation dependent, do nothing to the decl
4412 // - otherwise find its instantiated decl.
4413 if (isa<ParmVarDecl>(D) && !ParentDC->isDependentContext() &&
4414 !cast<ParmVarDecl>(D)->getType()->isInstantiationDependentType())
4416 if (isa<ParmVarDecl>(D) || isa<NonTypeTemplateParmDecl>(D) ||
4417 isa<TemplateTypeParmDecl>(D) || isa<TemplateTemplateParmDecl>(D) ||
4418 (ParentDC->isFunctionOrMethod() && ParentDC->isDependentContext()) ||
4419 (isa<CXXRecordDecl>(D) && cast<CXXRecordDecl>(D)->isLambda())) {
4420 // D is a local of some kind. Look into the map of local
4421 // declarations to their instantiations.
4422 if (CurrentInstantiationScope) {
4423 if (auto Found = CurrentInstantiationScope->findInstantiationOf(D)) {
4424 if (Decl *FD = Found->dyn_cast<Decl *>())
4425 return cast<NamedDecl>(FD);
4427 int PackIdx = ArgumentPackSubstitutionIndex;
4428 assert(PackIdx != -1 &&
4429 "found declaration pack but not pack expanding");
4430 typedef LocalInstantiationScope::DeclArgumentPack DeclArgumentPack;
4431 return cast<NamedDecl>((*Found->get<DeclArgumentPack *>())[PackIdx]);
4435 // If we're performing a partial substitution during template argument
4436 // deduction, we may not have values for template parameters yet. They
4437 // just map to themselves.
4438 if (isa<NonTypeTemplateParmDecl>(D) || isa<TemplateTypeParmDecl>(D) ||
4439 isa<TemplateTemplateParmDecl>(D))
4442 if (D->isInvalidDecl())
4445 // Normally this function only searches for already instantiated declaration
4446 // however we have to make an exclusion for local types used before
4447 // definition as in the code:
4449 // template<typename T> void f1() {
4450 // void g1(struct x1);
4454 // In this case instantiation of the type of 'g1' requires definition of
4455 // 'x1', which is defined later. Error recovery may produce an enum used
4456 // before definition. In these cases we need to instantiate relevant
4457 // declarations here.
4458 bool NeedInstantiate = false;
4459 if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(D))
4460 NeedInstantiate = RD->isLocalClass();
4462 NeedInstantiate = isa<EnumDecl>(D);
4463 if (NeedInstantiate) {
4464 Decl *Inst = SubstDecl(D, CurContext, TemplateArgs);
4465 CurrentInstantiationScope->InstantiatedLocal(D, Inst);
4466 return cast<TypeDecl>(Inst);
4469 // If we didn't find the decl, then we must have a label decl that hasn't
4470 // been found yet. Lazily instantiate it and return it now.
4471 assert(isa<LabelDecl>(D));
4473 Decl *Inst = SubstDecl(D, CurContext, TemplateArgs);
4474 assert(Inst && "Failed to instantiate label??");
4476 CurrentInstantiationScope->InstantiatedLocal(D, Inst);
4477 return cast<LabelDecl>(Inst);
4480 // For variable template specializations, update those that are still
4482 if (VarTemplateSpecializationDecl *VarSpec =
4483 dyn_cast<VarTemplateSpecializationDecl>(D)) {
4484 bool InstantiationDependent = false;
4485 const TemplateArgumentListInfo &VarTemplateArgs =
4486 VarSpec->getTemplateArgsInfo();
4487 if (TemplateSpecializationType::anyDependentTemplateArguments(
4488 VarTemplateArgs, InstantiationDependent))
4489 D = cast<NamedDecl>(
4490 SubstDecl(D, VarSpec->getDeclContext(), TemplateArgs));
4494 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(D)) {
4495 if (!Record->isDependentContext())
4498 // Determine whether this record is the "templated" declaration describing
4499 // a class template or class template partial specialization.
4500 ClassTemplateDecl *ClassTemplate = Record->getDescribedClassTemplate();
4502 ClassTemplate = ClassTemplate->getCanonicalDecl();
4503 else if (ClassTemplatePartialSpecializationDecl *PartialSpec
4504 = dyn_cast<ClassTemplatePartialSpecializationDecl>(Record))
4505 ClassTemplate = PartialSpec->getSpecializedTemplate()->getCanonicalDecl();
4507 // Walk the current context to find either the record or an instantiation of
4509 DeclContext *DC = CurContext;
4510 while (!DC->isFileContext()) {
4511 // If we're performing substitution while we're inside the template
4512 // definition, we'll find our own context. We're done.
4513 if (DC->Equals(Record))
4516 if (CXXRecordDecl *InstRecord = dyn_cast<CXXRecordDecl>(DC)) {
4517 // Check whether we're in the process of instantiating a class template
4518 // specialization of the template we're mapping.
4519 if (ClassTemplateSpecializationDecl *InstSpec
4520 = dyn_cast<ClassTemplateSpecializationDecl>(InstRecord)){
4521 ClassTemplateDecl *SpecTemplate = InstSpec->getSpecializedTemplate();
4522 if (ClassTemplate && isInstantiationOf(ClassTemplate, SpecTemplate))
4526 // Check whether we're in the process of instantiating a member class.
4527 if (isInstantiationOf(Record, InstRecord))
4531 // Move to the outer template scope.
4532 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(DC)) {
4533 if (FD->getFriendObjectKind() && FD->getDeclContext()->isFileContext()){
4534 DC = FD->getLexicalDeclContext();
4539 DC = DC->getParent();
4542 // Fall through to deal with other dependent record types (e.g.,
4543 // anonymous unions in class templates).
4546 if (!ParentDC->isDependentContext())
4549 ParentDC = FindInstantiatedContext(Loc, ParentDC, TemplateArgs);
4553 if (ParentDC != D->getDeclContext()) {
4554 // We performed some kind of instantiation in the parent context,
4555 // so now we need to look into the instantiated parent context to
4556 // find the instantiation of the declaration D.
4558 // If our context used to be dependent, we may need to instantiate
4559 // it before performing lookup into that context.
4560 bool IsBeingInstantiated = false;
4561 if (CXXRecordDecl *Spec = dyn_cast<CXXRecordDecl>(ParentDC)) {
4562 if (!Spec->isDependentContext()) {
4563 QualType T = Context.getTypeDeclType(Spec);
4564 const RecordType *Tag = T->getAs<RecordType>();
4565 assert(Tag && "type of non-dependent record is not a RecordType");
4566 if (Tag->isBeingDefined())
4567 IsBeingInstantiated = true;
4568 if (!Tag->isBeingDefined() &&
4569 RequireCompleteType(Loc, T, diag::err_incomplete_type))
4572 ParentDC = Tag->getDecl();
4576 NamedDecl *Result = nullptr;
4577 if (D->getDeclName()) {
4578 DeclContext::lookup_result Found = ParentDC->lookup(D->getDeclName());
4579 Result = findInstantiationOf(Context, D, Found.begin(), Found.end());
4581 // Since we don't have a name for the entity we're looking for,
4582 // our only option is to walk through all of the declarations to
4583 // find that name. This will occur in a few cases:
4585 // - anonymous struct/union within a template
4586 // - unnamed class/struct/union/enum within a template
4588 // FIXME: Find a better way to find these instantiations!
4589 Result = findInstantiationOf(Context, D,
4590 ParentDC->decls_begin(),
4591 ParentDC->decls_end());
4595 if (isa<UsingShadowDecl>(D)) {
4596 // UsingShadowDecls can instantiate to nothing because of using hiding.
4597 } else if (Diags.hasErrorOccurred()) {
4598 // We've already complained about something, so most likely this
4599 // declaration failed to instantiate. There's no point in complaining
4600 // further, since this is normal in invalid code.
4601 } else if (IsBeingInstantiated) {
4602 // The class in which this member exists is currently being
4603 // instantiated, and we haven't gotten around to instantiating this
4604 // member yet. This can happen when the code uses forward declarations
4605 // of member classes, and introduces ordering dependencies via
4606 // template instantiation.
4607 Diag(Loc, diag::err_member_not_yet_instantiated)
4609 << Context.getTypeDeclType(cast<CXXRecordDecl>(ParentDC));
4610 Diag(D->getLocation(), diag::note_non_instantiated_member_here);
4611 } else if (EnumConstantDecl *ED = dyn_cast<EnumConstantDecl>(D)) {
4612 // This enumeration constant was found when the template was defined,
4613 // but can't be found in the instantiation. This can happen if an
4614 // unscoped enumeration member is explicitly specialized.
4615 EnumDecl *Enum = cast<EnumDecl>(ED->getLexicalDeclContext());
4616 EnumDecl *Spec = cast<EnumDecl>(FindInstantiatedDecl(Loc, Enum,
4618 assert(Spec->getTemplateSpecializationKind() ==
4619 TSK_ExplicitSpecialization);
4620 Diag(Loc, diag::err_enumerator_does_not_exist)
4622 << Context.getTypeDeclType(cast<TypeDecl>(Spec->getDeclContext()));
4623 Diag(Spec->getLocation(), diag::note_enum_specialized_here)
4624 << Context.getTypeDeclType(Spec);
4626 // We should have found something, but didn't.
4627 llvm_unreachable("Unable to find instantiation of declaration!");
4637 /// \brief Performs template instantiation for all implicit template
4638 /// instantiations we have seen until this point.
4639 void Sema::PerformPendingInstantiations(bool LocalOnly) {
4640 while (!PendingLocalImplicitInstantiations.empty() ||
4641 (!LocalOnly && !PendingInstantiations.empty())) {
4642 PendingImplicitInstantiation Inst;
4644 if (PendingLocalImplicitInstantiations.empty()) {
4645 Inst = PendingInstantiations.front();
4646 PendingInstantiations.pop_front();
4648 Inst = PendingLocalImplicitInstantiations.front();
4649 PendingLocalImplicitInstantiations.pop_front();
4652 // Instantiate function definitions
4653 if (FunctionDecl *Function = dyn_cast<FunctionDecl>(Inst.first)) {
4654 PrettyDeclStackTraceEntry CrashInfo(*this, Function, SourceLocation(),
4655 "instantiating function definition");
4656 bool DefinitionRequired = Function->getTemplateSpecializationKind() ==
4657 TSK_ExplicitInstantiationDefinition;
4658 InstantiateFunctionDefinition(/*FIXME:*/Inst.second, Function, true,
4659 DefinitionRequired);
4663 // Instantiate variable definitions
4664 VarDecl *Var = cast<VarDecl>(Inst.first);
4666 assert((Var->isStaticDataMember() ||
4667 isa<VarTemplateSpecializationDecl>(Var)) &&
4668 "Not a static data member, nor a variable template"
4669 " specialization?");
4671 // Don't try to instantiate declarations if the most recent redeclaration
4673 if (Var->getMostRecentDecl()->isInvalidDecl())
4676 // Check if the most recent declaration has changed the specialization kind
4677 // and removed the need for implicit instantiation.
4678 switch (Var->getMostRecentDecl()->getTemplateSpecializationKind()) {
4679 case TSK_Undeclared:
4680 llvm_unreachable("Cannot instantitiate an undeclared specialization.");
4681 case TSK_ExplicitInstantiationDeclaration:
4682 case TSK_ExplicitSpecialization:
4683 continue; // No longer need to instantiate this type.
4684 case TSK_ExplicitInstantiationDefinition:
4685 // We only need an instantiation if the pending instantiation *is* the
4686 // explicit instantiation.
4687 if (Var != Var->getMostRecentDecl()) continue;
4688 case TSK_ImplicitInstantiation:
4692 PrettyDeclStackTraceEntry CrashInfo(*this, Var, SourceLocation(),
4693 "instantiating variable definition");
4694 bool DefinitionRequired = Var->getTemplateSpecializationKind() ==
4695 TSK_ExplicitInstantiationDefinition;
4697 // Instantiate static data member definitions or variable template
4699 InstantiateVariableDefinition(/*FIXME:*/ Inst.second, Var, true,
4700 DefinitionRequired);
4704 void Sema::PerformDependentDiagnostics(const DeclContext *Pattern,
4705 const MultiLevelTemplateArgumentList &TemplateArgs) {
4706 for (auto DD : Pattern->ddiags()) {
4707 switch (DD->getKind()) {
4708 case DependentDiagnostic::Access:
4709 HandleDependentAccessCheck(*DD, TemplateArgs);