1 //===------- SemaTemplateInstantiate.cpp - C++ Template 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.
11 //===----------------------------------------------------------------------===/
13 #include "clang/Sema/SemaInternal.h"
14 #include "TreeTransform.h"
15 #include "clang/AST/ASTConsumer.h"
16 #include "clang/AST/ASTContext.h"
17 #include "clang/AST/ASTLambda.h"
18 #include "clang/AST/DeclTemplate.h"
19 #include "clang/AST/Expr.h"
20 #include "clang/Basic/LangOptions.h"
21 #include "clang/Sema/DeclSpec.h"
22 #include "clang/Sema/Initialization.h"
23 #include "clang/Sema/Lookup.h"
24 #include "clang/Sema/Template.h"
25 #include "clang/Sema/TemplateDeduction.h"
27 using namespace clang;
30 //===----------------------------------------------------------------------===/
31 // Template Instantiation Support
32 //===----------------------------------------------------------------------===/
34 /// \brief Retrieve the template argument list(s) that should be used to
35 /// instantiate the definition of the given declaration.
37 /// \param D the declaration for which we are computing template instantiation
40 /// \param Innermost if non-NULL, the innermost template argument list.
42 /// \param RelativeToPrimary true if we should get the template
43 /// arguments relative to the primary template, even when we're
44 /// dealing with a specialization. This is only relevant for function
45 /// template specializations.
47 /// \param Pattern If non-NULL, indicates the pattern from which we will be
48 /// instantiating the definition of the given declaration, \p D. This is
49 /// used to determine the proper set of template instantiation arguments for
50 /// friend function template specializations.
51 MultiLevelTemplateArgumentList
52 Sema::getTemplateInstantiationArgs(NamedDecl *D,
53 const TemplateArgumentList *Innermost,
54 bool RelativeToPrimary,
55 const FunctionDecl *Pattern) {
56 // Accumulate the set of template argument lists in this structure.
57 MultiLevelTemplateArgumentList Result;
60 Result.addOuterTemplateArguments(Innermost);
62 DeclContext *Ctx = dyn_cast<DeclContext>(D);
64 Ctx = D->getDeclContext();
66 // Add template arguments from a variable template instantiation.
67 if (VarTemplateSpecializationDecl *Spec =
68 dyn_cast<VarTemplateSpecializationDecl>(D)) {
69 // We're done when we hit an explicit specialization.
70 if (Spec->getSpecializationKind() == TSK_ExplicitSpecialization &&
71 !isa<VarTemplatePartialSpecializationDecl>(Spec))
74 Result.addOuterTemplateArguments(&Spec->getTemplateInstantiationArgs());
76 // If this variable template specialization was instantiated from a
77 // specialized member that is a variable template, we're done.
78 assert(Spec->getSpecializedTemplate() && "No variable template?");
79 llvm::PointerUnion<VarTemplateDecl*,
80 VarTemplatePartialSpecializationDecl*> Specialized
81 = Spec->getSpecializedTemplateOrPartial();
82 if (VarTemplatePartialSpecializationDecl *Partial =
83 Specialized.dyn_cast<VarTemplatePartialSpecializationDecl *>()) {
84 if (Partial->isMemberSpecialization())
87 VarTemplateDecl *Tmpl = Specialized.get<VarTemplateDecl *>();
88 if (Tmpl->isMemberSpecialization())
93 // If we have a template template parameter with translation unit context,
94 // then we're performing substitution into a default template argument of
95 // this template template parameter before we've constructed the template
96 // that will own this template template parameter. In this case, we
97 // use empty template parameter lists for all of the outer templates
98 // to avoid performing any substitutions.
99 if (Ctx->isTranslationUnit()) {
100 if (TemplateTemplateParmDecl *TTP
101 = dyn_cast<TemplateTemplateParmDecl>(D)) {
102 for (unsigned I = 0, N = TTP->getDepth() + 1; I != N; ++I)
103 Result.addOuterTemplateArguments(None);
109 while (!Ctx->isFileContext()) {
110 // Add template arguments from a class template instantiation.
111 if (ClassTemplateSpecializationDecl *Spec
112 = dyn_cast<ClassTemplateSpecializationDecl>(Ctx)) {
113 // We're done when we hit an explicit specialization.
114 if (Spec->getSpecializationKind() == TSK_ExplicitSpecialization &&
115 !isa<ClassTemplatePartialSpecializationDecl>(Spec))
118 Result.addOuterTemplateArguments(&Spec->getTemplateInstantiationArgs());
120 // If this class template specialization was instantiated from a
121 // specialized member that is a class template, we're done.
122 assert(Spec->getSpecializedTemplate() && "No class template?");
123 if (Spec->getSpecializedTemplate()->isMemberSpecialization())
126 // Add template arguments from a function template specialization.
127 else if (FunctionDecl *Function = dyn_cast<FunctionDecl>(Ctx)) {
128 if (!RelativeToPrimary &&
129 (Function->getTemplateSpecializationKind() ==
130 TSK_ExplicitSpecialization &&
131 !Function->getClassScopeSpecializationPattern()))
134 if (const TemplateArgumentList *TemplateArgs
135 = Function->getTemplateSpecializationArgs()) {
136 // Add the template arguments for this specialization.
137 Result.addOuterTemplateArguments(TemplateArgs);
139 // If this function was instantiated from a specialized member that is
140 // a function template, we're done.
141 assert(Function->getPrimaryTemplate() && "No function template?");
142 if (Function->getPrimaryTemplate()->isMemberSpecialization())
145 // If this function is a generic lambda specialization, we are done.
146 if (isGenericLambdaCallOperatorSpecialization(Function))
149 } else if (FunctionTemplateDecl *FunTmpl
150 = Function->getDescribedFunctionTemplate()) {
151 // Add the "injected" template arguments.
152 Result.addOuterTemplateArguments(FunTmpl->getInjectedTemplateArgs());
155 // If this is a friend declaration and it declares an entity at
156 // namespace scope, take arguments from its lexical parent
157 // instead of its semantic parent, unless of course the pattern we're
158 // instantiating actually comes from the file's context!
159 if (Function->getFriendObjectKind() &&
160 Function->getDeclContext()->isFileContext() &&
161 (!Pattern || !Pattern->getLexicalDeclContext()->isFileContext())) {
162 Ctx = Function->getLexicalDeclContext();
163 RelativeToPrimary = false;
166 } else if (CXXRecordDecl *Rec = dyn_cast<CXXRecordDecl>(Ctx)) {
167 if (ClassTemplateDecl *ClassTemplate = Rec->getDescribedClassTemplate()) {
168 QualType T = ClassTemplate->getInjectedClassNameSpecialization();
169 const TemplateSpecializationType *TST =
170 cast<TemplateSpecializationType>(Context.getCanonicalType(T));
171 Result.addOuterTemplateArguments(
172 llvm::makeArrayRef(TST->getArgs(), TST->getNumArgs()));
173 if (ClassTemplate->isMemberSpecialization())
178 Ctx = Ctx->getParent();
179 RelativeToPrimary = false;
185 bool Sema::ActiveTemplateInstantiation::isInstantiationRecord() const {
187 case TemplateInstantiation:
188 case ExceptionSpecInstantiation:
189 case DefaultTemplateArgumentInstantiation:
190 case DefaultFunctionArgumentInstantiation:
191 case ExplicitTemplateArgumentSubstitution:
192 case DeducedTemplateArgumentSubstitution:
193 case PriorTemplateArgumentSubstitution:
196 case DefaultTemplateArgumentChecking:
200 llvm_unreachable("Invalid InstantiationKind!");
203 Sema::InstantiatingTemplate::InstantiatingTemplate(
204 Sema &SemaRef, ActiveTemplateInstantiation::InstantiationKind Kind,
205 SourceLocation PointOfInstantiation, SourceRange InstantiationRange,
206 Decl *Entity, NamedDecl *Template, ArrayRef<TemplateArgument> TemplateArgs,
207 sema::TemplateDeductionInfo *DeductionInfo)
208 : SemaRef(SemaRef), SavedInNonInstantiationSFINAEContext(
209 SemaRef.InNonInstantiationSFINAEContext) {
210 // Don't allow further instantiation if a fatal error has occcured. Any
211 // diagnostics we might have raised will not be visible.
212 if (SemaRef.Diags.hasFatalErrorOccurred()) {
216 Invalid = CheckInstantiationDepth(PointOfInstantiation, InstantiationRange);
218 ActiveTemplateInstantiation Inst;
220 Inst.PointOfInstantiation = PointOfInstantiation;
221 Inst.Entity = Entity;
222 Inst.Template = Template;
223 Inst.TemplateArgs = TemplateArgs.data();
224 Inst.NumTemplateArgs = TemplateArgs.size();
225 Inst.DeductionInfo = DeductionInfo;
226 Inst.InstantiationRange = InstantiationRange;
227 SemaRef.InNonInstantiationSFINAEContext = false;
228 SemaRef.ActiveTemplateInstantiations.push_back(Inst);
229 if (!Inst.isInstantiationRecord())
230 ++SemaRef.NonInstantiationEntries;
234 Sema::InstantiatingTemplate::InstantiatingTemplate(
235 Sema &SemaRef, SourceLocation PointOfInstantiation, Decl *Entity,
236 SourceRange InstantiationRange)
237 : InstantiatingTemplate(SemaRef,
238 ActiveTemplateInstantiation::TemplateInstantiation,
239 PointOfInstantiation, InstantiationRange, Entity) {}
241 Sema::InstantiatingTemplate::InstantiatingTemplate(
242 Sema &SemaRef, SourceLocation PointOfInstantiation, FunctionDecl *Entity,
243 ExceptionSpecification, SourceRange InstantiationRange)
244 : InstantiatingTemplate(
245 SemaRef, ActiveTemplateInstantiation::ExceptionSpecInstantiation,
246 PointOfInstantiation, InstantiationRange, Entity) {}
248 Sema::InstantiatingTemplate::InstantiatingTemplate(
249 Sema &SemaRef, SourceLocation PointOfInstantiation, TemplateDecl *Template,
250 ArrayRef<TemplateArgument> TemplateArgs, SourceRange InstantiationRange)
251 : InstantiatingTemplate(
253 ActiveTemplateInstantiation::DefaultTemplateArgumentInstantiation,
254 PointOfInstantiation, InstantiationRange, Template, nullptr,
257 Sema::InstantiatingTemplate::InstantiatingTemplate(
258 Sema &SemaRef, SourceLocation PointOfInstantiation,
259 FunctionTemplateDecl *FunctionTemplate,
260 ArrayRef<TemplateArgument> TemplateArgs,
261 ActiveTemplateInstantiation::InstantiationKind Kind,
262 sema::TemplateDeductionInfo &DeductionInfo, SourceRange InstantiationRange)
263 : InstantiatingTemplate(SemaRef, Kind, PointOfInstantiation,
264 InstantiationRange, FunctionTemplate, nullptr,
265 TemplateArgs, &DeductionInfo) {}
267 Sema::InstantiatingTemplate::InstantiatingTemplate(
268 Sema &SemaRef, SourceLocation PointOfInstantiation,
269 ClassTemplatePartialSpecializationDecl *PartialSpec,
270 ArrayRef<TemplateArgument> TemplateArgs,
271 sema::TemplateDeductionInfo &DeductionInfo, SourceRange InstantiationRange)
272 : InstantiatingTemplate(
274 ActiveTemplateInstantiation::DeducedTemplateArgumentSubstitution,
275 PointOfInstantiation, InstantiationRange, PartialSpec, nullptr,
276 TemplateArgs, &DeductionInfo) {}
278 Sema::InstantiatingTemplate::InstantiatingTemplate(
279 Sema &SemaRef, SourceLocation PointOfInstantiation,
280 VarTemplatePartialSpecializationDecl *PartialSpec,
281 ArrayRef<TemplateArgument> TemplateArgs,
282 sema::TemplateDeductionInfo &DeductionInfo, SourceRange InstantiationRange)
283 : InstantiatingTemplate(
285 ActiveTemplateInstantiation::DeducedTemplateArgumentSubstitution,
286 PointOfInstantiation, InstantiationRange, PartialSpec, nullptr,
287 TemplateArgs, &DeductionInfo) {}
289 Sema::InstantiatingTemplate::InstantiatingTemplate(
290 Sema &SemaRef, SourceLocation PointOfInstantiation, ParmVarDecl *Param,
291 ArrayRef<TemplateArgument> TemplateArgs, SourceRange InstantiationRange)
292 : InstantiatingTemplate(
294 ActiveTemplateInstantiation::DefaultFunctionArgumentInstantiation,
295 PointOfInstantiation, InstantiationRange, Param, nullptr,
298 Sema::InstantiatingTemplate::InstantiatingTemplate(
299 Sema &SemaRef, SourceLocation PointOfInstantiation, NamedDecl *Template,
300 NonTypeTemplateParmDecl *Param, ArrayRef<TemplateArgument> TemplateArgs,
301 SourceRange InstantiationRange)
302 : InstantiatingTemplate(
304 ActiveTemplateInstantiation::PriorTemplateArgumentSubstitution,
305 PointOfInstantiation, InstantiationRange, Param, Template,
308 Sema::InstantiatingTemplate::InstantiatingTemplate(
309 Sema &SemaRef, SourceLocation PointOfInstantiation, NamedDecl *Template,
310 TemplateTemplateParmDecl *Param, ArrayRef<TemplateArgument> TemplateArgs,
311 SourceRange InstantiationRange)
312 : InstantiatingTemplate(
314 ActiveTemplateInstantiation::PriorTemplateArgumentSubstitution,
315 PointOfInstantiation, InstantiationRange, Param, Template,
318 Sema::InstantiatingTemplate::InstantiatingTemplate(
319 Sema &SemaRef, SourceLocation PointOfInstantiation, TemplateDecl *Template,
320 NamedDecl *Param, ArrayRef<TemplateArgument> TemplateArgs,
321 SourceRange InstantiationRange)
322 : InstantiatingTemplate(
323 SemaRef, ActiveTemplateInstantiation::DefaultTemplateArgumentChecking,
324 PointOfInstantiation, InstantiationRange, Param, Template,
327 void Sema::InstantiatingTemplate::Clear() {
329 if (!SemaRef.ActiveTemplateInstantiations.back().isInstantiationRecord()) {
330 assert(SemaRef.NonInstantiationEntries > 0);
331 --SemaRef.NonInstantiationEntries;
333 SemaRef.InNonInstantiationSFINAEContext
334 = SavedInNonInstantiationSFINAEContext;
336 // Name lookup no longer looks in this template's defining module.
337 assert(SemaRef.ActiveTemplateInstantiations.size() >=
338 SemaRef.ActiveTemplateInstantiationLookupModules.size() &&
339 "forgot to remove a lookup module for a template instantiation");
340 if (SemaRef.ActiveTemplateInstantiations.size() ==
341 SemaRef.ActiveTemplateInstantiationLookupModules.size()) {
342 if (Module *M = SemaRef.ActiveTemplateInstantiationLookupModules.back())
343 SemaRef.LookupModulesCache.erase(M);
344 SemaRef.ActiveTemplateInstantiationLookupModules.pop_back();
347 SemaRef.ActiveTemplateInstantiations.pop_back();
352 bool Sema::InstantiatingTemplate::CheckInstantiationDepth(
353 SourceLocation PointOfInstantiation,
354 SourceRange InstantiationRange) {
355 assert(SemaRef.NonInstantiationEntries <=
356 SemaRef.ActiveTemplateInstantiations.size());
357 if ((SemaRef.ActiveTemplateInstantiations.size() -
358 SemaRef.NonInstantiationEntries)
359 <= SemaRef.getLangOpts().InstantiationDepth)
362 SemaRef.Diag(PointOfInstantiation,
363 diag::err_template_recursion_depth_exceeded)
364 << SemaRef.getLangOpts().InstantiationDepth
365 << InstantiationRange;
366 SemaRef.Diag(PointOfInstantiation, diag::note_template_recursion_depth)
367 << SemaRef.getLangOpts().InstantiationDepth;
371 /// \brief Prints the current instantiation stack through a series of
373 void Sema::PrintInstantiationStack() {
374 // Determine which template instantiations to skip, if any.
375 unsigned SkipStart = ActiveTemplateInstantiations.size(), SkipEnd = SkipStart;
376 unsigned Limit = Diags.getTemplateBacktraceLimit();
377 if (Limit && Limit < ActiveTemplateInstantiations.size()) {
378 SkipStart = Limit / 2 + Limit % 2;
379 SkipEnd = ActiveTemplateInstantiations.size() - Limit / 2;
382 // FIXME: In all of these cases, we need to show the template arguments
383 unsigned InstantiationIdx = 0;
384 for (SmallVectorImpl<ActiveTemplateInstantiation>::reverse_iterator
385 Active = ActiveTemplateInstantiations.rbegin(),
386 ActiveEnd = ActiveTemplateInstantiations.rend();
388 ++Active, ++InstantiationIdx) {
389 // Skip this instantiation?
390 if (InstantiationIdx >= SkipStart && InstantiationIdx < SkipEnd) {
391 if (InstantiationIdx == SkipStart) {
392 // Note that we're skipping instantiations.
393 Diags.Report(Active->PointOfInstantiation,
394 diag::note_instantiation_contexts_suppressed)
395 << unsigned(ActiveTemplateInstantiations.size() - Limit);
400 switch (Active->Kind) {
401 case ActiveTemplateInstantiation::TemplateInstantiation: {
402 Decl *D = Active->Entity;
403 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(D)) {
404 unsigned DiagID = diag::note_template_member_class_here;
405 if (isa<ClassTemplateSpecializationDecl>(Record))
406 DiagID = diag::note_template_class_instantiation_here;
407 Diags.Report(Active->PointOfInstantiation, DiagID)
408 << Context.getTypeDeclType(Record)
409 << Active->InstantiationRange;
410 } else if (FunctionDecl *Function = dyn_cast<FunctionDecl>(D)) {
412 if (Function->getPrimaryTemplate())
413 DiagID = diag::note_function_template_spec_here;
415 DiagID = diag::note_template_member_function_here;
416 Diags.Report(Active->PointOfInstantiation, DiagID)
418 << Active->InstantiationRange;
419 } else if (VarDecl *VD = dyn_cast<VarDecl>(D)) {
420 Diags.Report(Active->PointOfInstantiation,
421 VD->isStaticDataMember()?
422 diag::note_template_static_data_member_def_here
423 : diag::note_template_variable_def_here)
425 << Active->InstantiationRange;
426 } else if (EnumDecl *ED = dyn_cast<EnumDecl>(D)) {
427 Diags.Report(Active->PointOfInstantiation,
428 diag::note_template_enum_def_here)
430 << Active->InstantiationRange;
431 } else if (FieldDecl *FD = dyn_cast<FieldDecl>(D)) {
432 Diags.Report(Active->PointOfInstantiation,
433 diag::note_template_nsdmi_here)
434 << FD << Active->InstantiationRange;
436 Diags.Report(Active->PointOfInstantiation,
437 diag::note_template_type_alias_instantiation_here)
438 << cast<TypeAliasTemplateDecl>(D)
439 << Active->InstantiationRange;
444 case ActiveTemplateInstantiation::DefaultTemplateArgumentInstantiation: {
445 TemplateDecl *Template = cast<TemplateDecl>(Active->Entity);
446 SmallVector<char, 128> TemplateArgsStr;
447 llvm::raw_svector_ostream OS(TemplateArgsStr);
448 Template->printName(OS);
449 TemplateSpecializationType::PrintTemplateArgumentList(OS,
450 Active->TemplateArgs,
451 Active->NumTemplateArgs,
452 getPrintingPolicy());
453 Diags.Report(Active->PointOfInstantiation,
454 diag::note_default_arg_instantiation_here)
456 << Active->InstantiationRange;
460 case ActiveTemplateInstantiation::ExplicitTemplateArgumentSubstitution: {
461 FunctionTemplateDecl *FnTmpl = cast<FunctionTemplateDecl>(Active->Entity);
462 Diags.Report(Active->PointOfInstantiation,
463 diag::note_explicit_template_arg_substitution_here)
465 << getTemplateArgumentBindingsText(FnTmpl->getTemplateParameters(),
466 Active->TemplateArgs,
467 Active->NumTemplateArgs)
468 << Active->InstantiationRange;
472 case ActiveTemplateInstantiation::DeducedTemplateArgumentSubstitution:
473 if (ClassTemplatePartialSpecializationDecl *PartialSpec =
474 dyn_cast<ClassTemplatePartialSpecializationDecl>(Active->Entity)) {
475 Diags.Report(Active->PointOfInstantiation,
476 diag::note_partial_spec_deduct_instantiation_here)
477 << Context.getTypeDeclType(PartialSpec)
478 << getTemplateArgumentBindingsText(
479 PartialSpec->getTemplateParameters(),
480 Active->TemplateArgs,
481 Active->NumTemplateArgs)
482 << Active->InstantiationRange;
484 FunctionTemplateDecl *FnTmpl
485 = cast<FunctionTemplateDecl>(Active->Entity);
486 Diags.Report(Active->PointOfInstantiation,
487 diag::note_function_template_deduction_instantiation_here)
489 << getTemplateArgumentBindingsText(FnTmpl->getTemplateParameters(),
490 Active->TemplateArgs,
491 Active->NumTemplateArgs)
492 << Active->InstantiationRange;
496 case ActiveTemplateInstantiation::DefaultFunctionArgumentInstantiation: {
497 ParmVarDecl *Param = cast<ParmVarDecl>(Active->Entity);
498 FunctionDecl *FD = cast<FunctionDecl>(Param->getDeclContext());
500 SmallVector<char, 128> TemplateArgsStr;
501 llvm::raw_svector_ostream OS(TemplateArgsStr);
503 TemplateSpecializationType::PrintTemplateArgumentList(OS,
504 Active->TemplateArgs,
505 Active->NumTemplateArgs,
506 getPrintingPolicy());
507 Diags.Report(Active->PointOfInstantiation,
508 diag::note_default_function_arg_instantiation_here)
510 << Active->InstantiationRange;
514 case ActiveTemplateInstantiation::PriorTemplateArgumentSubstitution: {
515 NamedDecl *Parm = cast<NamedDecl>(Active->Entity);
517 if (!Parm->getName().empty())
518 Name = std::string(" '") + Parm->getName().str() + "'";
520 TemplateParameterList *TemplateParams = nullptr;
521 if (TemplateDecl *Template = dyn_cast<TemplateDecl>(Active->Template))
522 TemplateParams = Template->getTemplateParameters();
525 cast<ClassTemplatePartialSpecializationDecl>(Active->Template)
526 ->getTemplateParameters();
527 Diags.Report(Active->PointOfInstantiation,
528 diag::note_prior_template_arg_substitution)
529 << isa<TemplateTemplateParmDecl>(Parm)
531 << getTemplateArgumentBindingsText(TemplateParams,
532 Active->TemplateArgs,
533 Active->NumTemplateArgs)
534 << Active->InstantiationRange;
538 case ActiveTemplateInstantiation::DefaultTemplateArgumentChecking: {
539 TemplateParameterList *TemplateParams = nullptr;
540 if (TemplateDecl *Template = dyn_cast<TemplateDecl>(Active->Template))
541 TemplateParams = Template->getTemplateParameters();
544 cast<ClassTemplatePartialSpecializationDecl>(Active->Template)
545 ->getTemplateParameters();
547 Diags.Report(Active->PointOfInstantiation,
548 diag::note_template_default_arg_checking)
549 << getTemplateArgumentBindingsText(TemplateParams,
550 Active->TemplateArgs,
551 Active->NumTemplateArgs)
552 << Active->InstantiationRange;
556 case ActiveTemplateInstantiation::ExceptionSpecInstantiation:
557 Diags.Report(Active->PointOfInstantiation,
558 diag::note_template_exception_spec_instantiation_here)
559 << cast<FunctionDecl>(Active->Entity)
560 << Active->InstantiationRange;
566 Optional<TemplateDeductionInfo *> Sema::isSFINAEContext() const {
567 if (InNonInstantiationSFINAEContext)
568 return Optional<TemplateDeductionInfo *>(nullptr);
570 for (SmallVectorImpl<ActiveTemplateInstantiation>::const_reverse_iterator
571 Active = ActiveTemplateInstantiations.rbegin(),
572 ActiveEnd = ActiveTemplateInstantiations.rend();
576 switch(Active->Kind) {
577 case ActiveTemplateInstantiation::TemplateInstantiation:
578 // An instantiation of an alias template may or may not be a SFINAE
579 // context, depending on what else is on the stack.
580 if (isa<TypeAliasTemplateDecl>(Active->Entity))
583 case ActiveTemplateInstantiation::DefaultFunctionArgumentInstantiation:
584 case ActiveTemplateInstantiation::ExceptionSpecInstantiation:
585 // This is a template instantiation, so there is no SFINAE.
588 case ActiveTemplateInstantiation::DefaultTemplateArgumentInstantiation:
589 case ActiveTemplateInstantiation::PriorTemplateArgumentSubstitution:
590 case ActiveTemplateInstantiation::DefaultTemplateArgumentChecking:
591 // A default template argument instantiation and substitution into
592 // template parameters with arguments for prior parameters may or may
593 // not be a SFINAE context; look further up the stack.
596 case ActiveTemplateInstantiation::ExplicitTemplateArgumentSubstitution:
597 case ActiveTemplateInstantiation::DeducedTemplateArgumentSubstitution:
598 // We're either substitution explicitly-specified template arguments
599 // or deduced template arguments, so SFINAE applies.
600 assert(Active->DeductionInfo && "Missing deduction info pointer");
601 return Active->DeductionInfo;
608 /// \brief Retrieve the depth and index of a parameter pack.
609 static std::pair<unsigned, unsigned>
610 getDepthAndIndex(NamedDecl *ND) {
611 if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(ND))
612 return std::make_pair(TTP->getDepth(), TTP->getIndex());
614 if (NonTypeTemplateParmDecl *NTTP = dyn_cast<NonTypeTemplateParmDecl>(ND))
615 return std::make_pair(NTTP->getDepth(), NTTP->getIndex());
617 TemplateTemplateParmDecl *TTP = cast<TemplateTemplateParmDecl>(ND);
618 return std::make_pair(TTP->getDepth(), TTP->getIndex());
621 //===----------------------------------------------------------------------===/
622 // Template Instantiation for Types
623 //===----------------------------------------------------------------------===/
625 class TemplateInstantiator : public TreeTransform<TemplateInstantiator> {
626 const MultiLevelTemplateArgumentList &TemplateArgs;
628 DeclarationName Entity;
631 typedef TreeTransform<TemplateInstantiator> inherited;
633 TemplateInstantiator(Sema &SemaRef,
634 const MultiLevelTemplateArgumentList &TemplateArgs,
636 DeclarationName Entity)
637 : inherited(SemaRef), TemplateArgs(TemplateArgs), Loc(Loc),
640 /// \brief Determine whether the given type \p T has already been
643 /// For the purposes of template instantiation, a type has already been
644 /// transformed if it is NULL or if it is not dependent.
645 bool AlreadyTransformed(QualType T);
647 /// \brief Returns the location of the entity being instantiated, if known.
648 SourceLocation getBaseLocation() { return Loc; }
650 /// \brief Returns the name of the entity being instantiated, if any.
651 DeclarationName getBaseEntity() { return Entity; }
653 /// \brief Sets the "base" location and entity when that
654 /// information is known based on another transformation.
655 void setBase(SourceLocation Loc, DeclarationName Entity) {
657 this->Entity = Entity;
660 bool TryExpandParameterPacks(SourceLocation EllipsisLoc,
661 SourceRange PatternRange,
662 ArrayRef<UnexpandedParameterPack> Unexpanded,
663 bool &ShouldExpand, bool &RetainExpansion,
664 Optional<unsigned> &NumExpansions) {
665 return getSema().CheckParameterPacksForExpansion(EllipsisLoc,
666 PatternRange, Unexpanded,
673 void ExpandingFunctionParameterPack(ParmVarDecl *Pack) {
674 SemaRef.CurrentInstantiationScope->MakeInstantiatedLocalArgPack(Pack);
677 TemplateArgument ForgetPartiallySubstitutedPack() {
678 TemplateArgument Result;
679 if (NamedDecl *PartialPack
680 = SemaRef.CurrentInstantiationScope->getPartiallySubstitutedPack()){
681 MultiLevelTemplateArgumentList &TemplateArgs
682 = const_cast<MultiLevelTemplateArgumentList &>(this->TemplateArgs);
683 unsigned Depth, Index;
684 std::tie(Depth, Index) = getDepthAndIndex(PartialPack);
685 if (TemplateArgs.hasTemplateArgument(Depth, Index)) {
686 Result = TemplateArgs(Depth, Index);
687 TemplateArgs.setArgument(Depth, Index, TemplateArgument());
694 void RememberPartiallySubstitutedPack(TemplateArgument Arg) {
698 if (NamedDecl *PartialPack
699 = SemaRef.CurrentInstantiationScope->getPartiallySubstitutedPack()){
700 MultiLevelTemplateArgumentList &TemplateArgs
701 = const_cast<MultiLevelTemplateArgumentList &>(this->TemplateArgs);
702 unsigned Depth, Index;
703 std::tie(Depth, Index) = getDepthAndIndex(PartialPack);
704 TemplateArgs.setArgument(Depth, Index, Arg);
708 /// \brief Transform the given declaration by instantiating a reference to
709 /// this declaration.
710 Decl *TransformDecl(SourceLocation Loc, Decl *D);
712 void transformAttrs(Decl *Old, Decl *New) {
713 SemaRef.InstantiateAttrs(TemplateArgs, Old, New);
716 void transformedLocalDecl(Decl *Old, Decl *New) {
717 // If we've instantiated the call operator of a lambda or the call
718 // operator template of a generic lambda, update the "instantiation of"
720 auto *NewMD = dyn_cast<CXXMethodDecl>(New);
721 if (NewMD && isLambdaCallOperator(NewMD)) {
722 auto *OldMD = dyn_cast<CXXMethodDecl>(Old);
723 if (auto *NewTD = NewMD->getDescribedFunctionTemplate())
724 NewTD->setInstantiatedFromMemberTemplate(
725 OldMD->getDescribedFunctionTemplate());
727 NewMD->setInstantiationOfMemberFunction(OldMD,
728 TSK_ImplicitInstantiation);
731 SemaRef.CurrentInstantiationScope->InstantiatedLocal(Old, New);
734 /// \brief Transform the definition of the given declaration by
735 /// instantiating it.
736 Decl *TransformDefinition(SourceLocation Loc, Decl *D);
738 /// \brief Transform the first qualifier within a scope by instantiating the
740 NamedDecl *TransformFirstQualifierInScope(NamedDecl *D, SourceLocation Loc);
742 /// \brief Rebuild the exception declaration and register the declaration
743 /// as an instantiated local.
744 VarDecl *RebuildExceptionDecl(VarDecl *ExceptionDecl,
745 TypeSourceInfo *Declarator,
746 SourceLocation StartLoc,
747 SourceLocation NameLoc,
748 IdentifierInfo *Name);
750 /// \brief Rebuild the Objective-C exception declaration and register the
751 /// declaration as an instantiated local.
752 VarDecl *RebuildObjCExceptionDecl(VarDecl *ExceptionDecl,
753 TypeSourceInfo *TSInfo, QualType T);
755 /// \brief Check for tag mismatches when instantiating an
757 QualType RebuildElaboratedType(SourceLocation KeywordLoc,
758 ElaboratedTypeKeyword Keyword,
759 NestedNameSpecifierLoc QualifierLoc,
763 TransformTemplateName(CXXScopeSpec &SS, TemplateName Name,
764 SourceLocation NameLoc,
765 QualType ObjectType = QualType(),
766 NamedDecl *FirstQualifierInScope = nullptr);
768 const LoopHintAttr *TransformLoopHintAttr(const LoopHintAttr *LH);
770 ExprResult TransformPredefinedExpr(PredefinedExpr *E);
771 ExprResult TransformDeclRefExpr(DeclRefExpr *E);
772 ExprResult TransformCXXDefaultArgExpr(CXXDefaultArgExpr *E);
774 ExprResult TransformTemplateParmRefExpr(DeclRefExpr *E,
775 NonTypeTemplateParmDecl *D);
776 ExprResult TransformSubstNonTypeTemplateParmPackExpr(
777 SubstNonTypeTemplateParmPackExpr *E);
779 /// \brief Rebuild a DeclRefExpr for a ParmVarDecl reference.
780 ExprResult RebuildParmVarDeclRefExpr(ParmVarDecl *PD, SourceLocation Loc);
782 /// \brief Transform a reference to a function parameter pack.
783 ExprResult TransformFunctionParmPackRefExpr(DeclRefExpr *E,
786 /// \brief Transform a FunctionParmPackExpr which was built when we couldn't
787 /// expand a function parameter pack reference which refers to an expanded
789 ExprResult TransformFunctionParmPackExpr(FunctionParmPackExpr *E);
791 QualType TransformFunctionProtoType(TypeLocBuilder &TLB,
792 FunctionProtoTypeLoc TL) {
793 // Call the base version; it will forward to our overridden version below.
794 return inherited::TransformFunctionProtoType(TLB, TL);
797 template<typename Fn>
798 QualType TransformFunctionProtoType(TypeLocBuilder &TLB,
799 FunctionProtoTypeLoc TL,
800 CXXRecordDecl *ThisContext,
801 unsigned ThisTypeQuals,
802 Fn TransformExceptionSpec);
804 ParmVarDecl *TransformFunctionTypeParam(ParmVarDecl *OldParm,
806 Optional<unsigned> NumExpansions,
807 bool ExpectParameterPack);
809 /// \brief Transforms a template type parameter type by performing
810 /// substitution of the corresponding template type argument.
811 QualType TransformTemplateTypeParmType(TypeLocBuilder &TLB,
812 TemplateTypeParmTypeLoc TL);
814 /// \brief Transforms an already-substituted template type parameter pack
815 /// into either itself (if we aren't substituting into its pack expansion)
816 /// or the appropriate substituted argument.
817 QualType TransformSubstTemplateTypeParmPackType(TypeLocBuilder &TLB,
818 SubstTemplateTypeParmPackTypeLoc TL);
820 ExprResult TransformLambdaExpr(LambdaExpr *E) {
821 LocalInstantiationScope Scope(SemaRef, /*CombineWithOuterScope=*/true);
822 return TreeTransform<TemplateInstantiator>::TransformLambdaExpr(E);
825 TemplateParameterList *TransformTemplateParameterList(
826 TemplateParameterList *OrigTPL) {
827 if (!OrigTPL || !OrigTPL->size()) return OrigTPL;
829 DeclContext *Owner = OrigTPL->getParam(0)->getDeclContext();
830 TemplateDeclInstantiator DeclInstantiator(getSema(),
831 /* DeclContext *Owner */ Owner, TemplateArgs);
832 return DeclInstantiator.SubstTemplateParams(OrigTPL);
835 ExprResult transformNonTypeTemplateParmRef(NonTypeTemplateParmDecl *parm,
837 TemplateArgument arg);
841 bool TemplateInstantiator::AlreadyTransformed(QualType T) {
845 if (T->isInstantiationDependentType() || T->isVariablyModifiedType())
848 getSema().MarkDeclarationsReferencedInType(Loc, T);
852 static TemplateArgument
853 getPackSubstitutedTemplateArgument(Sema &S, TemplateArgument Arg) {
854 assert(S.ArgumentPackSubstitutionIndex >= 0);
855 assert(S.ArgumentPackSubstitutionIndex < (int)Arg.pack_size());
856 Arg = Arg.pack_begin()[S.ArgumentPackSubstitutionIndex];
857 if (Arg.isPackExpansion())
858 Arg = Arg.getPackExpansionPattern();
862 Decl *TemplateInstantiator::TransformDecl(SourceLocation Loc, Decl *D) {
866 if (TemplateTemplateParmDecl *TTP = dyn_cast<TemplateTemplateParmDecl>(D)) {
867 if (TTP->getDepth() < TemplateArgs.getNumLevels()) {
868 // If the corresponding template argument is NULL or non-existent, it's
869 // because we are performing instantiation from explicitly-specified
870 // template arguments in a function template, but there were some
871 // arguments left unspecified.
872 if (!TemplateArgs.hasTemplateArgument(TTP->getDepth(),
876 TemplateArgument Arg = TemplateArgs(TTP->getDepth(), TTP->getPosition());
878 if (TTP->isParameterPack()) {
879 assert(Arg.getKind() == TemplateArgument::Pack &&
880 "Missing argument pack");
881 Arg = getPackSubstitutedTemplateArgument(getSema(), Arg);
884 TemplateName Template = Arg.getAsTemplate();
885 assert(!Template.isNull() && Template.getAsTemplateDecl() &&
886 "Wrong kind of template template argument");
887 return Template.getAsTemplateDecl();
890 // Fall through to find the instantiated declaration for this template
891 // template parameter.
894 return SemaRef.FindInstantiatedDecl(Loc, cast<NamedDecl>(D), TemplateArgs);
897 Decl *TemplateInstantiator::TransformDefinition(SourceLocation Loc, Decl *D) {
898 Decl *Inst = getSema().SubstDecl(D, getSema().CurContext, TemplateArgs);
902 getSema().CurrentInstantiationScope->InstantiatedLocal(D, Inst);
907 TemplateInstantiator::TransformFirstQualifierInScope(NamedDecl *D,
908 SourceLocation Loc) {
909 // If the first part of the nested-name-specifier was a template type
910 // parameter, instantiate that type parameter down to a tag type.
911 if (TemplateTypeParmDecl *TTPD = dyn_cast_or_null<TemplateTypeParmDecl>(D)) {
912 const TemplateTypeParmType *TTP
913 = cast<TemplateTypeParmType>(getSema().Context.getTypeDeclType(TTPD));
915 if (TTP->getDepth() < TemplateArgs.getNumLevels()) {
916 // FIXME: This needs testing w/ member access expressions.
917 TemplateArgument Arg = TemplateArgs(TTP->getDepth(), TTP->getIndex());
919 if (TTP->isParameterPack()) {
920 assert(Arg.getKind() == TemplateArgument::Pack &&
921 "Missing argument pack");
923 if (getSema().ArgumentPackSubstitutionIndex == -1)
926 Arg = getPackSubstitutedTemplateArgument(getSema(), Arg);
929 QualType T = Arg.getAsType();
931 return cast_or_null<NamedDecl>(TransformDecl(Loc, D));
933 if (const TagType *Tag = T->getAs<TagType>())
934 return Tag->getDecl();
936 // The resulting type is not a tag; complain.
937 getSema().Diag(Loc, diag::err_nested_name_spec_non_tag) << T;
942 return cast_or_null<NamedDecl>(TransformDecl(Loc, D));
946 TemplateInstantiator::RebuildExceptionDecl(VarDecl *ExceptionDecl,
947 TypeSourceInfo *Declarator,
948 SourceLocation StartLoc,
949 SourceLocation NameLoc,
950 IdentifierInfo *Name) {
951 VarDecl *Var = inherited::RebuildExceptionDecl(ExceptionDecl, Declarator,
952 StartLoc, NameLoc, Name);
954 getSema().CurrentInstantiationScope->InstantiatedLocal(ExceptionDecl, Var);
958 VarDecl *TemplateInstantiator::RebuildObjCExceptionDecl(VarDecl *ExceptionDecl,
959 TypeSourceInfo *TSInfo,
961 VarDecl *Var = inherited::RebuildObjCExceptionDecl(ExceptionDecl, TSInfo, T);
963 getSema().CurrentInstantiationScope->InstantiatedLocal(ExceptionDecl, Var);
968 TemplateInstantiator::RebuildElaboratedType(SourceLocation KeywordLoc,
969 ElaboratedTypeKeyword Keyword,
970 NestedNameSpecifierLoc QualifierLoc,
972 if (const TagType *TT = T->getAs<TagType>()) {
973 TagDecl* TD = TT->getDecl();
975 SourceLocation TagLocation = KeywordLoc;
977 IdentifierInfo *Id = TD->getIdentifier();
979 // TODO: should we even warn on struct/class mismatches for this? Seems
980 // like it's likely to produce a lot of spurious errors.
981 if (Id && Keyword != ETK_None && Keyword != ETK_Typename) {
982 TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForKeyword(Keyword);
983 if (!SemaRef.isAcceptableTagRedeclaration(TD, Kind, /*isDefinition*/false,
985 SemaRef.Diag(TagLocation, diag::err_use_with_wrong_tag)
987 << FixItHint::CreateReplacement(SourceRange(TagLocation),
989 SemaRef.Diag(TD->getLocation(), diag::note_previous_use);
994 return TreeTransform<TemplateInstantiator>::RebuildElaboratedType(KeywordLoc,
1000 TemplateName TemplateInstantiator::TransformTemplateName(CXXScopeSpec &SS,
1002 SourceLocation NameLoc,
1003 QualType ObjectType,
1004 NamedDecl *FirstQualifierInScope) {
1005 if (TemplateTemplateParmDecl *TTP
1006 = dyn_cast_or_null<TemplateTemplateParmDecl>(Name.getAsTemplateDecl())) {
1007 if (TTP->getDepth() < TemplateArgs.getNumLevels()) {
1008 // If the corresponding template argument is NULL or non-existent, it's
1009 // because we are performing instantiation from explicitly-specified
1010 // template arguments in a function template, but there were some
1011 // arguments left unspecified.
1012 if (!TemplateArgs.hasTemplateArgument(TTP->getDepth(),
1013 TTP->getPosition()))
1016 TemplateArgument Arg = TemplateArgs(TTP->getDepth(), TTP->getPosition());
1018 if (TTP->isParameterPack()) {
1019 assert(Arg.getKind() == TemplateArgument::Pack &&
1020 "Missing argument pack");
1022 if (getSema().ArgumentPackSubstitutionIndex == -1) {
1023 // We have the template argument pack to substitute, but we're not
1024 // actually expanding the enclosing pack expansion yet. So, just
1025 // keep the entire argument pack.
1026 return getSema().Context.getSubstTemplateTemplateParmPack(TTP, Arg);
1029 Arg = getPackSubstitutedTemplateArgument(getSema(), Arg);
1032 TemplateName Template = Arg.getAsTemplate();
1033 assert(!Template.isNull() && "Null template template argument");
1035 // We don't ever want to substitute for a qualified template name, since
1036 // the qualifier is handled separately. So, look through the qualified
1037 // template name to its underlying declaration.
1038 if (QualifiedTemplateName *QTN = Template.getAsQualifiedTemplateName())
1039 Template = TemplateName(QTN->getTemplateDecl());
1041 Template = getSema().Context.getSubstTemplateTemplateParm(TTP, Template);
1046 if (SubstTemplateTemplateParmPackStorage *SubstPack
1047 = Name.getAsSubstTemplateTemplateParmPack()) {
1048 if (getSema().ArgumentPackSubstitutionIndex == -1)
1051 TemplateArgument Arg = SubstPack->getArgumentPack();
1052 Arg = getPackSubstitutedTemplateArgument(getSema(), Arg);
1053 return Arg.getAsTemplate();
1056 return inherited::TransformTemplateName(SS, Name, NameLoc, ObjectType,
1057 FirstQualifierInScope);
1061 TemplateInstantiator::TransformPredefinedExpr(PredefinedExpr *E) {
1062 if (!E->isTypeDependent())
1065 return getSema().BuildPredefinedExpr(E->getLocation(), E->getIdentType());
1069 TemplateInstantiator::TransformTemplateParmRefExpr(DeclRefExpr *E,
1070 NonTypeTemplateParmDecl *NTTP) {
1071 // If the corresponding template argument is NULL or non-existent, it's
1072 // because we are performing instantiation from explicitly-specified
1073 // template arguments in a function template, but there were some
1074 // arguments left unspecified.
1075 if (!TemplateArgs.hasTemplateArgument(NTTP->getDepth(),
1076 NTTP->getPosition()))
1079 TemplateArgument Arg = TemplateArgs(NTTP->getDepth(), NTTP->getPosition());
1080 if (NTTP->isParameterPack()) {
1081 assert(Arg.getKind() == TemplateArgument::Pack &&
1082 "Missing argument pack");
1084 if (getSema().ArgumentPackSubstitutionIndex == -1) {
1085 // We have an argument pack, but we can't select a particular argument
1086 // out of it yet. Therefore, we'll build an expression to hold on to that
1088 QualType TargetType = SemaRef.SubstType(NTTP->getType(), TemplateArgs,
1090 NTTP->getDeclName());
1091 if (TargetType.isNull())
1094 return new (SemaRef.Context) SubstNonTypeTemplateParmPackExpr(TargetType,
1100 Arg = getPackSubstitutedTemplateArgument(getSema(), Arg);
1103 return transformNonTypeTemplateParmRef(NTTP, E->getLocation(), Arg);
1106 const LoopHintAttr *
1107 TemplateInstantiator::TransformLoopHintAttr(const LoopHintAttr *LH) {
1108 Expr *TransformedExpr = getDerived().TransformExpr(LH->getValue()).get();
1110 if (TransformedExpr == LH->getValue())
1113 // Generate error if there is a problem with the value.
1114 if (getSema().CheckLoopHintExpr(TransformedExpr, LH->getLocation()))
1117 // Create new LoopHintValueAttr with integral expression in place of the
1118 // non-type template parameter.
1119 return LoopHintAttr::CreateImplicit(
1120 getSema().Context, LH->getSemanticSpelling(), LH->getOption(),
1121 LH->getState(), TransformedExpr, LH->getRange());
1124 ExprResult TemplateInstantiator::transformNonTypeTemplateParmRef(
1125 NonTypeTemplateParmDecl *parm,
1127 TemplateArgument arg) {
1131 // The template argument itself might be an expression, in which
1132 // case we just return that expression.
1133 if (arg.getKind() == TemplateArgument::Expression) {
1134 Expr *argExpr = arg.getAsExpr();
1136 type = argExpr->getType();
1138 } else if (arg.getKind() == TemplateArgument::Declaration ||
1139 arg.getKind() == TemplateArgument::NullPtr) {
1141 if (arg.getKind() == TemplateArgument::Declaration) {
1142 VD = cast<ValueDecl>(arg.getAsDecl());
1144 // Find the instantiation of the template argument. This is
1145 // required for nested templates.
1146 VD = cast_or_null<ValueDecl>(
1147 getSema().FindInstantiatedDecl(loc, VD, TemplateArgs));
1151 // Propagate NULL template argument.
1155 // Derive the type we want the substituted decl to have. This had
1156 // better be non-dependent, or these checks will have serious problems.
1157 if (parm->isExpandedParameterPack()) {
1158 type = parm->getExpansionType(SemaRef.ArgumentPackSubstitutionIndex);
1159 } else if (parm->isParameterPack() &&
1160 isa<PackExpansionType>(parm->getType())) {
1161 type = SemaRef.SubstType(
1162 cast<PackExpansionType>(parm->getType())->getPattern(),
1163 TemplateArgs, loc, parm->getDeclName());
1165 type = SemaRef.SubstType(parm->getType(), TemplateArgs,
1166 loc, parm->getDeclName());
1168 assert(!type.isNull() && "type substitution failed for param type");
1169 assert(!type->isDependentType() && "param type still dependent");
1170 result = SemaRef.BuildExpressionFromDeclTemplateArgument(arg, type, loc);
1172 if (!result.isInvalid()) type = result.get()->getType();
1174 result = SemaRef.BuildExpressionFromIntegralTemplateArgument(arg, loc);
1176 // Note that this type can be different from the type of 'result',
1177 // e.g. if it's an enum type.
1178 type = arg.getIntegralType();
1180 if (result.isInvalid()) return ExprError();
1182 Expr *resultExpr = result.get();
1183 return new (SemaRef.Context) SubstNonTypeTemplateParmExpr(
1184 type, resultExpr->getValueKind(), loc, parm, resultExpr);
1188 TemplateInstantiator::TransformSubstNonTypeTemplateParmPackExpr(
1189 SubstNonTypeTemplateParmPackExpr *E) {
1190 if (getSema().ArgumentPackSubstitutionIndex == -1) {
1191 // We aren't expanding the parameter pack, so just return ourselves.
1195 TemplateArgument Arg = E->getArgumentPack();
1196 Arg = getPackSubstitutedTemplateArgument(getSema(), Arg);
1197 return transformNonTypeTemplateParmRef(E->getParameterPack(),
1198 E->getParameterPackLocation(),
1203 TemplateInstantiator::RebuildParmVarDeclRefExpr(ParmVarDecl *PD,
1204 SourceLocation Loc) {
1205 DeclarationNameInfo NameInfo(PD->getDeclName(), Loc);
1206 return getSema().BuildDeclarationNameExpr(CXXScopeSpec(), NameInfo, PD);
1210 TemplateInstantiator::TransformFunctionParmPackExpr(FunctionParmPackExpr *E) {
1211 if (getSema().ArgumentPackSubstitutionIndex != -1) {
1212 // We can expand this parameter pack now.
1213 ParmVarDecl *D = E->getExpansion(getSema().ArgumentPackSubstitutionIndex);
1214 ValueDecl *VD = cast_or_null<ValueDecl>(TransformDecl(E->getExprLoc(), D));
1217 return RebuildParmVarDeclRefExpr(cast<ParmVarDecl>(VD), E->getExprLoc());
1220 QualType T = TransformType(E->getType());
1224 // Transform each of the parameter expansions into the corresponding
1225 // parameters in the instantiation of the function decl.
1226 SmallVector<ParmVarDecl *, 8> Parms;
1227 Parms.reserve(E->getNumExpansions());
1228 for (FunctionParmPackExpr::iterator I = E->begin(), End = E->end();
1231 cast_or_null<ParmVarDecl>(TransformDecl(E->getExprLoc(), *I));
1237 return FunctionParmPackExpr::Create(getSema().Context, T,
1238 E->getParameterPack(),
1239 E->getParameterPackLocation(), Parms);
1243 TemplateInstantiator::TransformFunctionParmPackRefExpr(DeclRefExpr *E,
1245 typedef LocalInstantiationScope::DeclArgumentPack DeclArgumentPack;
1246 llvm::PointerUnion<Decl *, DeclArgumentPack *> *Found
1247 = getSema().CurrentInstantiationScope->findInstantiationOf(PD);
1248 assert(Found && "no instantiation for parameter pack");
1250 Decl *TransformedDecl;
1251 if (DeclArgumentPack *Pack = Found->dyn_cast<DeclArgumentPack *>()) {
1252 // If this is a reference to a function parameter pack which we can
1253 // substitute but can't yet expand, build a FunctionParmPackExpr for it.
1254 if (getSema().ArgumentPackSubstitutionIndex == -1) {
1255 QualType T = TransformType(E->getType());
1258 return FunctionParmPackExpr::Create(getSema().Context, T, PD,
1259 E->getExprLoc(), *Pack);
1262 TransformedDecl = (*Pack)[getSema().ArgumentPackSubstitutionIndex];
1264 TransformedDecl = Found->get<Decl*>();
1267 // We have either an unexpanded pack or a specific expansion.
1268 return RebuildParmVarDeclRefExpr(cast<ParmVarDecl>(TransformedDecl),
1273 TemplateInstantiator::TransformDeclRefExpr(DeclRefExpr *E) {
1274 NamedDecl *D = E->getDecl();
1276 // Handle references to non-type template parameters and non-type template
1278 if (NonTypeTemplateParmDecl *NTTP = dyn_cast<NonTypeTemplateParmDecl>(D)) {
1279 if (NTTP->getDepth() < TemplateArgs.getNumLevels())
1280 return TransformTemplateParmRefExpr(E, NTTP);
1282 // We have a non-type template parameter that isn't fully substituted;
1283 // FindInstantiatedDecl will find it in the local instantiation scope.
1286 // Handle references to function parameter packs.
1287 if (ParmVarDecl *PD = dyn_cast<ParmVarDecl>(D))
1288 if (PD->isParameterPack())
1289 return TransformFunctionParmPackRefExpr(E, PD);
1291 return TreeTransform<TemplateInstantiator>::TransformDeclRefExpr(E);
1294 ExprResult TemplateInstantiator::TransformCXXDefaultArgExpr(
1295 CXXDefaultArgExpr *E) {
1296 assert(!cast<FunctionDecl>(E->getParam()->getDeclContext())->
1297 getDescribedFunctionTemplate() &&
1298 "Default arg expressions are never formed in dependent cases.");
1299 return SemaRef.BuildCXXDefaultArgExpr(E->getUsedLocation(),
1300 cast<FunctionDecl>(E->getParam()->getDeclContext()),
1304 template<typename Fn>
1305 QualType TemplateInstantiator::TransformFunctionProtoType(TypeLocBuilder &TLB,
1306 FunctionProtoTypeLoc TL,
1307 CXXRecordDecl *ThisContext,
1308 unsigned ThisTypeQuals,
1309 Fn TransformExceptionSpec) {
1310 // We need a local instantiation scope for this function prototype.
1311 LocalInstantiationScope Scope(SemaRef, /*CombineWithOuterScope=*/true);
1312 return inherited::TransformFunctionProtoType(
1313 TLB, TL, ThisContext, ThisTypeQuals, TransformExceptionSpec);
1317 TemplateInstantiator::TransformFunctionTypeParam(ParmVarDecl *OldParm,
1318 int indexAdjustment,
1319 Optional<unsigned> NumExpansions,
1320 bool ExpectParameterPack) {
1321 return SemaRef.SubstParmVarDecl(OldParm, TemplateArgs, indexAdjustment,
1322 NumExpansions, ExpectParameterPack);
1326 TemplateInstantiator::TransformTemplateTypeParmType(TypeLocBuilder &TLB,
1327 TemplateTypeParmTypeLoc TL) {
1328 const TemplateTypeParmType *T = TL.getTypePtr();
1329 if (T->getDepth() < TemplateArgs.getNumLevels()) {
1330 // Replace the template type parameter with its corresponding
1331 // template argument.
1333 // If the corresponding template argument is NULL or doesn't exist, it's
1334 // because we are performing instantiation from explicitly-specified
1335 // template arguments in a function template class, but there were some
1336 // arguments left unspecified.
1337 if (!TemplateArgs.hasTemplateArgument(T->getDepth(), T->getIndex())) {
1338 TemplateTypeParmTypeLoc NewTL
1339 = TLB.push<TemplateTypeParmTypeLoc>(TL.getType());
1340 NewTL.setNameLoc(TL.getNameLoc());
1341 return TL.getType();
1344 TemplateArgument Arg = TemplateArgs(T->getDepth(), T->getIndex());
1346 if (T->isParameterPack()) {
1347 assert(Arg.getKind() == TemplateArgument::Pack &&
1348 "Missing argument pack");
1350 if (getSema().ArgumentPackSubstitutionIndex == -1) {
1351 // We have the template argument pack, but we're not expanding the
1352 // enclosing pack expansion yet. Just save the template argument
1353 // pack for later substitution.
1355 = getSema().Context.getSubstTemplateTypeParmPackType(T, Arg);
1356 SubstTemplateTypeParmPackTypeLoc NewTL
1357 = TLB.push<SubstTemplateTypeParmPackTypeLoc>(Result);
1358 NewTL.setNameLoc(TL.getNameLoc());
1362 Arg = getPackSubstitutedTemplateArgument(getSema(), Arg);
1365 assert(Arg.getKind() == TemplateArgument::Type &&
1366 "Template argument kind mismatch");
1368 QualType Replacement = Arg.getAsType();
1370 // TODO: only do this uniquing once, at the start of instantiation.
1372 = getSema().Context.getSubstTemplateTypeParmType(T, Replacement);
1373 SubstTemplateTypeParmTypeLoc NewTL
1374 = TLB.push<SubstTemplateTypeParmTypeLoc>(Result);
1375 NewTL.setNameLoc(TL.getNameLoc());
1379 // The template type parameter comes from an inner template (e.g.,
1380 // the template parameter list of a member template inside the
1381 // template we are instantiating). Create a new template type
1382 // parameter with the template "level" reduced by one.
1383 TemplateTypeParmDecl *NewTTPDecl = nullptr;
1384 if (TemplateTypeParmDecl *OldTTPDecl = T->getDecl())
1385 NewTTPDecl = cast_or_null<TemplateTypeParmDecl>(
1386 TransformDecl(TL.getNameLoc(), OldTTPDecl));
1389 = getSema().Context.getTemplateTypeParmType(T->getDepth()
1390 - TemplateArgs.getNumLevels(),
1392 T->isParameterPack(),
1394 TemplateTypeParmTypeLoc NewTL = TLB.push<TemplateTypeParmTypeLoc>(Result);
1395 NewTL.setNameLoc(TL.getNameLoc());
1400 TemplateInstantiator::TransformSubstTemplateTypeParmPackType(
1401 TypeLocBuilder &TLB,
1402 SubstTemplateTypeParmPackTypeLoc TL) {
1403 if (getSema().ArgumentPackSubstitutionIndex == -1) {
1404 // We aren't expanding the parameter pack, so just return ourselves.
1405 SubstTemplateTypeParmPackTypeLoc NewTL
1406 = TLB.push<SubstTemplateTypeParmPackTypeLoc>(TL.getType());
1407 NewTL.setNameLoc(TL.getNameLoc());
1408 return TL.getType();
1411 TemplateArgument Arg = TL.getTypePtr()->getArgumentPack();
1412 Arg = getPackSubstitutedTemplateArgument(getSema(), Arg);
1413 QualType Result = Arg.getAsType();
1415 Result = getSema().Context.getSubstTemplateTypeParmType(
1416 TL.getTypePtr()->getReplacedParameter(),
1418 SubstTemplateTypeParmTypeLoc NewTL
1419 = TLB.push<SubstTemplateTypeParmTypeLoc>(Result);
1420 NewTL.setNameLoc(TL.getNameLoc());
1424 /// \brief Perform substitution on the type T with a given set of template
1427 /// This routine substitutes the given template arguments into the
1428 /// type T and produces the instantiated type.
1430 /// \param T the type into which the template arguments will be
1431 /// substituted. If this type is not dependent, it will be returned
1434 /// \param Args the template arguments that will be
1435 /// substituted for the top-level template parameters within T.
1437 /// \param Loc the location in the source code where this substitution
1438 /// is being performed. It will typically be the location of the
1439 /// declarator (if we're instantiating the type of some declaration)
1440 /// or the location of the type in the source code (if, e.g., we're
1441 /// instantiating the type of a cast expression).
1443 /// \param Entity the name of the entity associated with a declaration
1444 /// being instantiated (if any). May be empty to indicate that there
1445 /// is no such entity (if, e.g., this is a type that occurs as part of
1446 /// a cast expression) or that the entity has no name (e.g., an
1447 /// unnamed function parameter).
1449 /// \returns If the instantiation succeeds, the instantiated
1450 /// type. Otherwise, produces diagnostics and returns a NULL type.
1451 TypeSourceInfo *Sema::SubstType(TypeSourceInfo *T,
1452 const MultiLevelTemplateArgumentList &Args,
1454 DeclarationName Entity) {
1455 assert(!ActiveTemplateInstantiations.empty() &&
1456 "Cannot perform an instantiation without some context on the "
1457 "instantiation stack");
1459 if (!T->getType()->isInstantiationDependentType() &&
1460 !T->getType()->isVariablyModifiedType())
1463 TemplateInstantiator Instantiator(*this, Args, Loc, Entity);
1464 return Instantiator.TransformType(T);
1467 TypeSourceInfo *Sema::SubstType(TypeLoc TL,
1468 const MultiLevelTemplateArgumentList &Args,
1470 DeclarationName Entity) {
1471 assert(!ActiveTemplateInstantiations.empty() &&
1472 "Cannot perform an instantiation without some context on the "
1473 "instantiation stack");
1475 if (TL.getType().isNull())
1478 if (!TL.getType()->isInstantiationDependentType() &&
1479 !TL.getType()->isVariablyModifiedType()) {
1480 // FIXME: Make a copy of the TypeLoc data here, so that we can
1481 // return a new TypeSourceInfo. Inefficient!
1483 TLB.pushFullCopy(TL);
1484 return TLB.getTypeSourceInfo(Context, TL.getType());
1487 TemplateInstantiator Instantiator(*this, Args, Loc, Entity);
1489 TLB.reserve(TL.getFullDataSize());
1490 QualType Result = Instantiator.TransformType(TLB, TL);
1491 if (Result.isNull())
1494 return TLB.getTypeSourceInfo(Context, Result);
1497 /// Deprecated form of the above.
1498 QualType Sema::SubstType(QualType T,
1499 const MultiLevelTemplateArgumentList &TemplateArgs,
1500 SourceLocation Loc, DeclarationName Entity) {
1501 assert(!ActiveTemplateInstantiations.empty() &&
1502 "Cannot perform an instantiation without some context on the "
1503 "instantiation stack");
1505 // If T is not a dependent type or a variably-modified type, there
1506 // is nothing to do.
1507 if (!T->isInstantiationDependentType() && !T->isVariablyModifiedType())
1510 TemplateInstantiator Instantiator(*this, TemplateArgs, Loc, Entity);
1511 return Instantiator.TransformType(T);
1514 static bool NeedsInstantiationAsFunctionType(TypeSourceInfo *T) {
1515 if (T->getType()->isInstantiationDependentType() ||
1516 T->getType()->isVariablyModifiedType())
1519 TypeLoc TL = T->getTypeLoc().IgnoreParens();
1520 if (!TL.getAs<FunctionProtoTypeLoc>())
1523 FunctionProtoTypeLoc FP = TL.castAs<FunctionProtoTypeLoc>();
1524 for (unsigned I = 0, E = FP.getNumParams(); I != E; ++I) {
1525 ParmVarDecl *P = FP.getParam(I);
1527 // This must be synthesized from a typedef.
1530 // The parameter's type as written might be dependent even if the
1531 // decayed type was not dependent.
1532 if (TypeSourceInfo *TSInfo = P->getTypeSourceInfo())
1533 if (TSInfo->getType()->isInstantiationDependentType())
1536 // TODO: currently we always rebuild expressions. When we
1537 // properly get lazier about this, we should use the same
1538 // logic to avoid rebuilding prototypes here.
1539 if (P->hasDefaultArg())
1546 /// A form of SubstType intended specifically for instantiating the
1547 /// type of a FunctionDecl. Its purpose is solely to force the
1548 /// instantiation of default-argument expressions and to avoid
1549 /// instantiating an exception-specification.
1550 TypeSourceInfo *Sema::SubstFunctionDeclType(TypeSourceInfo *T,
1551 const MultiLevelTemplateArgumentList &Args,
1553 DeclarationName Entity,
1554 CXXRecordDecl *ThisContext,
1555 unsigned ThisTypeQuals) {
1556 assert(!ActiveTemplateInstantiations.empty() &&
1557 "Cannot perform an instantiation without some context on the "
1558 "instantiation stack");
1560 if (!NeedsInstantiationAsFunctionType(T))
1563 TemplateInstantiator Instantiator(*this, Args, Loc, Entity);
1567 TypeLoc TL = T->getTypeLoc();
1568 TLB.reserve(TL.getFullDataSize());
1572 if (FunctionProtoTypeLoc Proto =
1573 TL.IgnoreParens().getAs<FunctionProtoTypeLoc>()) {
1574 // Instantiate the type, other than its exception specification. The
1575 // exception specification is instantiated in InitFunctionInstantiation
1576 // once we've built the FunctionDecl.
1577 // FIXME: Set the exception specification to EST_Uninstantiated here,
1578 // instead of rebuilding the function type again later.
1579 Result = Instantiator.TransformFunctionProtoType(
1580 TLB, Proto, ThisContext, ThisTypeQuals,
1581 [](FunctionProtoType::ExceptionSpecInfo &ESI,
1582 bool &Changed) { return false; });
1584 Result = Instantiator.TransformType(TLB, TL);
1586 if (Result.isNull())
1589 return TLB.getTypeSourceInfo(Context, Result);
1592 void Sema::SubstExceptionSpec(FunctionDecl *New, const FunctionProtoType *Proto,
1593 const MultiLevelTemplateArgumentList &Args) {
1594 FunctionProtoType::ExceptionSpecInfo ESI =
1595 Proto->getExtProtoInfo().ExceptionSpec;
1596 assert(ESI.Type != EST_Uninstantiated);
1598 TemplateInstantiator Instantiator(*this, Args, New->getLocation(),
1599 New->getDeclName());
1601 SmallVector<QualType, 4> ExceptionStorage;
1602 bool Changed = false;
1603 if (Instantiator.TransformExceptionSpec(
1604 New->getTypeSourceInfo()->getTypeLoc().getLocEnd(), ESI,
1605 ExceptionStorage, Changed))
1606 // On error, recover by dropping the exception specification.
1607 ESI.Type = EST_None;
1609 UpdateExceptionSpec(New, ESI);
1612 ParmVarDecl *Sema::SubstParmVarDecl(ParmVarDecl *OldParm,
1613 const MultiLevelTemplateArgumentList &TemplateArgs,
1614 int indexAdjustment,
1615 Optional<unsigned> NumExpansions,
1616 bool ExpectParameterPack) {
1617 TypeSourceInfo *OldDI = OldParm->getTypeSourceInfo();
1618 TypeSourceInfo *NewDI = nullptr;
1620 TypeLoc OldTL = OldDI->getTypeLoc();
1621 if (PackExpansionTypeLoc ExpansionTL = OldTL.getAs<PackExpansionTypeLoc>()) {
1623 // We have a function parameter pack. Substitute into the pattern of the
1625 NewDI = SubstType(ExpansionTL.getPatternLoc(), TemplateArgs,
1626 OldParm->getLocation(), OldParm->getDeclName());
1630 if (NewDI->getType()->containsUnexpandedParameterPack()) {
1631 // We still have unexpanded parameter packs, which means that
1632 // our function parameter is still a function parameter pack.
1633 // Therefore, make its type a pack expansion type.
1634 NewDI = CheckPackExpansion(NewDI, ExpansionTL.getEllipsisLoc(),
1636 } else if (ExpectParameterPack) {
1637 // We expected to get a parameter pack but didn't (because the type
1638 // itself is not a pack expansion type), so complain. This can occur when
1639 // the substitution goes through an alias template that "loses" the
1641 Diag(OldParm->getLocation(),
1642 diag::err_function_parameter_pack_without_parameter_packs)
1643 << NewDI->getType();
1647 NewDI = SubstType(OldDI, TemplateArgs, OldParm->getLocation(),
1648 OldParm->getDeclName());
1654 if (NewDI->getType()->isVoidType()) {
1655 Diag(OldParm->getLocation(), diag::err_param_with_void_type);
1659 ParmVarDecl *NewParm = CheckParameter(Context.getTranslationUnitDecl(),
1660 OldParm->getInnerLocStart(),
1661 OldParm->getLocation(),
1662 OldParm->getIdentifier(),
1663 NewDI->getType(), NewDI,
1664 OldParm->getStorageClass());
1668 // Mark the (new) default argument as uninstantiated (if any).
1669 if (OldParm->hasUninstantiatedDefaultArg()) {
1670 Expr *Arg = OldParm->getUninstantiatedDefaultArg();
1671 NewParm->setUninstantiatedDefaultArg(Arg);
1672 } else if (OldParm->hasUnparsedDefaultArg()) {
1673 NewParm->setUnparsedDefaultArg();
1674 UnparsedDefaultArgInstantiations[OldParm].push_back(NewParm);
1675 } else if (Expr *Arg = OldParm->getDefaultArg()) {
1676 FunctionDecl *OwningFunc = cast<FunctionDecl>(OldParm->getDeclContext());
1677 if (OwningFunc->isLexicallyWithinFunctionOrMethod()) {
1678 // Instantiate default arguments for methods of local classes (DR1484)
1679 // and non-defining declarations.
1680 Sema::ContextRAII SavedContext(*this, OwningFunc);
1681 LocalInstantiationScope Local(*this);
1682 ExprResult NewArg = SubstExpr(Arg, TemplateArgs);
1683 if (NewArg.isUsable()) {
1684 // It would be nice if we still had this.
1685 SourceLocation EqualLoc = NewArg.get()->getLocStart();
1686 SetParamDefaultArgument(NewParm, NewArg.get(), EqualLoc);
1689 // FIXME: if we non-lazily instantiated non-dependent default args for
1690 // non-dependent parameter types we could remove a bunch of duplicate
1691 // conversion warnings for such arguments.
1692 NewParm->setUninstantiatedDefaultArg(Arg);
1696 NewParm->setHasInheritedDefaultArg(OldParm->hasInheritedDefaultArg());
1698 if (OldParm->isParameterPack() && !NewParm->isParameterPack()) {
1699 // Add the new parameter to the instantiated parameter pack.
1700 CurrentInstantiationScope->InstantiatedLocalPackArg(OldParm, NewParm);
1702 // Introduce an Old -> New mapping
1703 CurrentInstantiationScope->InstantiatedLocal(OldParm, NewParm);
1706 // FIXME: OldParm may come from a FunctionProtoType, in which case CurContext
1707 // can be anything, is this right ?
1708 NewParm->setDeclContext(CurContext);
1710 NewParm->setScopeInfo(OldParm->getFunctionScopeDepth(),
1711 OldParm->getFunctionScopeIndex() + indexAdjustment);
1713 InstantiateAttrs(TemplateArgs, OldParm, NewParm);
1718 /// \brief Substitute the given template arguments into the given set of
1719 /// parameters, producing the set of parameter types that would be generated
1720 /// from such a substitution.
1721 bool Sema::SubstParmTypes(SourceLocation Loc,
1722 ParmVarDecl **Params, unsigned NumParams,
1723 const MultiLevelTemplateArgumentList &TemplateArgs,
1724 SmallVectorImpl<QualType> &ParamTypes,
1725 SmallVectorImpl<ParmVarDecl *> *OutParams) {
1726 assert(!ActiveTemplateInstantiations.empty() &&
1727 "Cannot perform an instantiation without some context on the "
1728 "instantiation stack");
1730 TemplateInstantiator Instantiator(*this, TemplateArgs, Loc,
1732 return Instantiator.TransformFunctionTypeParams(Loc, Params, NumParams,
1733 nullptr, ParamTypes,
1737 /// \brief Perform substitution on the base class specifiers of the
1738 /// given class template specialization.
1740 /// Produces a diagnostic and returns true on error, returns false and
1741 /// attaches the instantiated base classes to the class template
1742 /// specialization if successful.
1744 Sema::SubstBaseSpecifiers(CXXRecordDecl *Instantiation,
1745 CXXRecordDecl *Pattern,
1746 const MultiLevelTemplateArgumentList &TemplateArgs) {
1747 bool Invalid = false;
1748 SmallVector<CXXBaseSpecifier*, 4> InstantiatedBases;
1749 for (const auto &Base : Pattern->bases()) {
1750 if (!Base.getType()->isDependentType()) {
1751 if (const CXXRecordDecl *RD = Base.getType()->getAsCXXRecordDecl()) {
1752 if (RD->isInvalidDecl())
1753 Instantiation->setInvalidDecl();
1755 InstantiatedBases.push_back(new (Context) CXXBaseSpecifier(Base));
1759 SourceLocation EllipsisLoc;
1760 TypeSourceInfo *BaseTypeLoc;
1761 if (Base.isPackExpansion()) {
1762 // This is a pack expansion. See whether we should expand it now, or
1763 // wait until later.
1764 SmallVector<UnexpandedParameterPack, 2> Unexpanded;
1765 collectUnexpandedParameterPacks(Base.getTypeSourceInfo()->getTypeLoc(),
1767 bool ShouldExpand = false;
1768 bool RetainExpansion = false;
1769 Optional<unsigned> NumExpansions;
1770 if (CheckParameterPacksForExpansion(Base.getEllipsisLoc(),
1771 Base.getSourceRange(),
1773 TemplateArgs, ShouldExpand,
1780 // If we should expand this pack expansion now, do so.
1782 for (unsigned I = 0; I != *NumExpansions; ++I) {
1783 Sema::ArgumentPackSubstitutionIndexRAII SubstIndex(*this, I);
1785 TypeSourceInfo *BaseTypeLoc = SubstType(Base.getTypeSourceInfo(),
1787 Base.getSourceRange().getBegin(),
1794 if (CXXBaseSpecifier *InstantiatedBase
1795 = CheckBaseSpecifier(Instantiation,
1796 Base.getSourceRange(),
1798 Base.getAccessSpecifierAsWritten(),
1801 InstantiatedBases.push_back(InstantiatedBase);
1809 // The resulting base specifier will (still) be a pack expansion.
1810 EllipsisLoc = Base.getEllipsisLoc();
1811 Sema::ArgumentPackSubstitutionIndexRAII SubstIndex(*this, -1);
1812 BaseTypeLoc = SubstType(Base.getTypeSourceInfo(),
1814 Base.getSourceRange().getBegin(),
1817 BaseTypeLoc = SubstType(Base.getTypeSourceInfo(),
1819 Base.getSourceRange().getBegin(),
1828 if (CXXBaseSpecifier *InstantiatedBase
1829 = CheckBaseSpecifier(Instantiation,
1830 Base.getSourceRange(),
1832 Base.getAccessSpecifierAsWritten(),
1835 InstantiatedBases.push_back(InstantiatedBase);
1840 if (!Invalid && AttachBaseSpecifiers(Instantiation, InstantiatedBases))
1846 // Defined via #include from SemaTemplateInstantiateDecl.cpp
1849 Attr *instantiateTemplateAttribute(const Attr *At, ASTContext &C, Sema &S,
1850 const MultiLevelTemplateArgumentList &TemplateArgs);
1854 /// Determine whether we would be unable to instantiate this template (because
1855 /// it either has no definition, or is in the process of being instantiated).
1856 static bool DiagnoseUninstantiableTemplate(Sema &S,
1857 SourceLocation PointOfInstantiation,
1858 TagDecl *Instantiation,
1859 bool InstantiatedFromMember,
1861 TagDecl *PatternDef,
1862 TemplateSpecializationKind TSK,
1863 bool Complain = true) {
1864 if (PatternDef && !PatternDef->isBeingDefined())
1867 if (!Complain || (PatternDef && PatternDef->isInvalidDecl())) {
1869 } else if (PatternDef) {
1870 assert(PatternDef->isBeingDefined());
1871 S.Diag(PointOfInstantiation,
1872 diag::err_template_instantiate_within_definition)
1873 << (TSK != TSK_ImplicitInstantiation)
1874 << S.Context.getTypeDeclType(Instantiation);
1875 // Not much point in noting the template declaration here, since
1876 // we're lexically inside it.
1877 Instantiation->setInvalidDecl();
1878 } else if (InstantiatedFromMember) {
1879 S.Diag(PointOfInstantiation,
1880 diag::err_implicit_instantiate_member_undefined)
1881 << S.Context.getTypeDeclType(Instantiation);
1882 S.Diag(Pattern->getLocation(), diag::note_member_declared_at);
1884 S.Diag(PointOfInstantiation, diag::err_template_instantiate_undefined)
1885 << (TSK != TSK_ImplicitInstantiation)
1886 << S.Context.getTypeDeclType(Instantiation);
1887 S.Diag(Pattern->getLocation(), diag::note_template_decl_here);
1890 // In general, Instantiation isn't marked invalid to get more than one
1891 // error for multiple undefined instantiations. But the code that does
1892 // explicit declaration -> explicit definition conversion can't handle
1893 // invalid declarations, so mark as invalid in that case.
1894 if (TSK == TSK_ExplicitInstantiationDeclaration)
1895 Instantiation->setInvalidDecl();
1899 /// \brief Instantiate the definition of a class from a given pattern.
1901 /// \param PointOfInstantiation The point of instantiation within the
1904 /// \param Instantiation is the declaration whose definition is being
1905 /// instantiated. This will be either a class template specialization
1906 /// or a member class of a class template specialization.
1908 /// \param Pattern is the pattern from which the instantiation
1909 /// occurs. This will be either the declaration of a class template or
1910 /// the declaration of a member class of a class template.
1912 /// \param TemplateArgs The template arguments to be substituted into
1915 /// \param TSK the kind of implicit or explicit instantiation to perform.
1917 /// \param Complain whether to complain if the class cannot be instantiated due
1918 /// to the lack of a definition.
1920 /// \returns true if an error occurred, false otherwise.
1922 Sema::InstantiateClass(SourceLocation PointOfInstantiation,
1923 CXXRecordDecl *Instantiation, CXXRecordDecl *Pattern,
1924 const MultiLevelTemplateArgumentList &TemplateArgs,
1925 TemplateSpecializationKind TSK,
1927 CXXRecordDecl *PatternDef
1928 = cast_or_null<CXXRecordDecl>(Pattern->getDefinition());
1929 if (DiagnoseUninstantiableTemplate(*this, PointOfInstantiation, Instantiation,
1930 Instantiation->getInstantiatedFromMemberClass(),
1931 Pattern, PatternDef, TSK, Complain))
1933 Pattern = PatternDef;
1935 // \brief Record the point of instantiation.
1936 if (MemberSpecializationInfo *MSInfo
1937 = Instantiation->getMemberSpecializationInfo()) {
1938 MSInfo->setTemplateSpecializationKind(TSK);
1939 MSInfo->setPointOfInstantiation(PointOfInstantiation);
1940 } else if (ClassTemplateSpecializationDecl *Spec
1941 = dyn_cast<ClassTemplateSpecializationDecl>(Instantiation)) {
1942 Spec->setTemplateSpecializationKind(TSK);
1943 Spec->setPointOfInstantiation(PointOfInstantiation);
1946 InstantiatingTemplate Inst(*this, PointOfInstantiation, Instantiation);
1947 if (Inst.isInvalid())
1950 // Enter the scope of this instantiation. We don't use
1951 // PushDeclContext because we don't have a scope.
1952 ContextRAII SavedContext(*this, Instantiation);
1953 EnterExpressionEvaluationContext EvalContext(*this,
1954 Sema::PotentiallyEvaluated);
1956 // If this is an instantiation of a local class, merge this local
1957 // instantiation scope with the enclosing scope. Otherwise, every
1958 // instantiation of a class has its own local instantiation scope.
1959 bool MergeWithParentScope = !Instantiation->isDefinedOutsideFunctionOrMethod();
1960 LocalInstantiationScope Scope(*this, MergeWithParentScope);
1962 // Pull attributes from the pattern onto the instantiation.
1963 InstantiateAttrs(TemplateArgs, Pattern, Instantiation);
1965 // Start the definition of this instantiation.
1966 Instantiation->startDefinition();
1968 // The instantiation is visible here, even if it was first declared in an
1969 // unimported module.
1970 Instantiation->setHidden(false);
1972 // FIXME: This loses the as-written tag kind for an explicit instantiation.
1973 Instantiation->setTagKind(Pattern->getTagKind());
1975 // Do substitution on the base class specifiers.
1976 if (SubstBaseSpecifiers(Instantiation, Pattern, TemplateArgs))
1977 Instantiation->setInvalidDecl();
1979 TemplateDeclInstantiator Instantiator(*this, Instantiation, TemplateArgs);
1980 SmallVector<Decl*, 4> Fields;
1981 // Delay instantiation of late parsed attributes.
1982 LateInstantiatedAttrVec LateAttrs;
1983 Instantiator.enableLateAttributeInstantiation(&LateAttrs);
1985 for (auto *Member : Pattern->decls()) {
1986 // Don't instantiate members not belonging in this semantic context.
1989 // template <int i> class A {
1993 // 'class B' has the template as lexical context but semantically it is
1994 // introduced in namespace scope.
1995 if (Member->getDeclContext() != Pattern)
1998 if (Member->isInvalidDecl()) {
1999 Instantiation->setInvalidDecl();
2003 Decl *NewMember = Instantiator.Visit(Member);
2005 if (FieldDecl *Field = dyn_cast<FieldDecl>(NewMember)) {
2006 Fields.push_back(Field);
2007 } else if (EnumDecl *Enum = dyn_cast<EnumDecl>(NewMember)) {
2008 // C++11 [temp.inst]p1: The implicit instantiation of a class template
2009 // specialization causes the implicit instantiation of the definitions
2010 // of unscoped member enumerations.
2011 // Record a point of instantiation for this implicit instantiation.
2012 if (TSK == TSK_ImplicitInstantiation && !Enum->isScoped() &&
2013 Enum->isCompleteDefinition()) {
2014 MemberSpecializationInfo *MSInfo =Enum->getMemberSpecializationInfo();
2015 assert(MSInfo && "no spec info for member enum specialization");
2016 MSInfo->setTemplateSpecializationKind(TSK_ImplicitInstantiation);
2017 MSInfo->setPointOfInstantiation(PointOfInstantiation);
2019 } else if (StaticAssertDecl *SA = dyn_cast<StaticAssertDecl>(NewMember)) {
2020 if (SA->isFailed()) {
2021 // A static_assert failed. Bail out; instantiating this
2022 // class is probably not meaningful.
2023 Instantiation->setInvalidDecl();
2028 if (NewMember->isInvalidDecl())
2029 Instantiation->setInvalidDecl();
2031 // FIXME: Eventually, a NULL return will mean that one of the
2032 // instantiations was a semantic disaster, and we'll want to mark the
2033 // declaration invalid.
2034 // For now, we expect to skip some members that we can't yet handle.
2038 // Finish checking fields.
2039 ActOnFields(nullptr, Instantiation->getLocation(), Instantiation, Fields,
2040 SourceLocation(), SourceLocation(), nullptr);
2041 CheckCompletedCXXClass(Instantiation);
2043 // Default arguments are parsed, if not instantiated. We can go instantiate
2044 // default arg exprs for default constructors if necessary now.
2045 ActOnFinishCXXNonNestedClass(Instantiation);
2047 // Instantiate late parsed attributes, and attach them to their decls.
2048 // See Sema::InstantiateAttrs
2049 for (LateInstantiatedAttrVec::iterator I = LateAttrs.begin(),
2050 E = LateAttrs.end(); I != E; ++I) {
2051 assert(CurrentInstantiationScope == Instantiator.getStartingScope());
2052 CurrentInstantiationScope = I->Scope;
2054 // Allow 'this' within late-parsed attributes.
2055 NamedDecl *ND = dyn_cast<NamedDecl>(I->NewDecl);
2056 CXXRecordDecl *ThisContext =
2057 dyn_cast_or_null<CXXRecordDecl>(ND->getDeclContext());
2058 CXXThisScopeRAII ThisScope(*this, ThisContext, /*TypeQuals*/0,
2059 ND && ND->isCXXInstanceMember());
2062 instantiateTemplateAttribute(I->TmplAttr, Context, *this, TemplateArgs);
2063 I->NewDecl->addAttr(NewAttr);
2064 LocalInstantiationScope::deleteScopes(I->Scope,
2065 Instantiator.getStartingScope());
2067 Instantiator.disableLateAttributeInstantiation();
2070 ActOnFinishDelayedMemberInitializers(Instantiation);
2072 // FIXME: We should do something similar for explicit instantiations so they
2073 // end up in the right module.
2074 if (TSK == TSK_ImplicitInstantiation) {
2075 Instantiation->setLocation(Pattern->getLocation());
2076 Instantiation->setLocStart(Pattern->getInnerLocStart());
2077 Instantiation->setRBraceLoc(Pattern->getRBraceLoc());
2080 if (!Instantiation->isInvalidDecl()) {
2081 // Perform any dependent diagnostics from the pattern.
2082 PerformDependentDiagnostics(Pattern, TemplateArgs);
2084 // Instantiate any out-of-line class template partial
2085 // specializations now.
2086 for (TemplateDeclInstantiator::delayed_partial_spec_iterator
2087 P = Instantiator.delayed_partial_spec_begin(),
2088 PEnd = Instantiator.delayed_partial_spec_end();
2090 if (!Instantiator.InstantiateClassTemplatePartialSpecialization(
2091 P->first, P->second)) {
2092 Instantiation->setInvalidDecl();
2097 // Instantiate any out-of-line variable template partial
2098 // specializations now.
2099 for (TemplateDeclInstantiator::delayed_var_partial_spec_iterator
2100 P = Instantiator.delayed_var_partial_spec_begin(),
2101 PEnd = Instantiator.delayed_var_partial_spec_end();
2103 if (!Instantiator.InstantiateVarTemplatePartialSpecialization(
2104 P->first, P->second)) {
2105 Instantiation->setInvalidDecl();
2111 // Exit the scope of this instantiation.
2114 if (!Instantiation->isInvalidDecl()) {
2115 Consumer.HandleTagDeclDefinition(Instantiation);
2117 // Always emit the vtable for an explicit instantiation definition
2118 // of a polymorphic class template specialization.
2119 if (TSK == TSK_ExplicitInstantiationDefinition)
2120 MarkVTableUsed(PointOfInstantiation, Instantiation, true);
2123 return Instantiation->isInvalidDecl();
2126 /// \brief Instantiate the definition of an enum from a given pattern.
2128 /// \param PointOfInstantiation The point of instantiation within the
2130 /// \param Instantiation is the declaration whose definition is being
2131 /// instantiated. This will be a member enumeration of a class
2132 /// temploid specialization, or a local enumeration within a
2133 /// function temploid specialization.
2134 /// \param Pattern The templated declaration from which the instantiation
2136 /// \param TemplateArgs The template arguments to be substituted into
2138 /// \param TSK The kind of implicit or explicit instantiation to perform.
2140 /// \return \c true if an error occurred, \c false otherwise.
2141 bool Sema::InstantiateEnum(SourceLocation PointOfInstantiation,
2142 EnumDecl *Instantiation, EnumDecl *Pattern,
2143 const MultiLevelTemplateArgumentList &TemplateArgs,
2144 TemplateSpecializationKind TSK) {
2145 EnumDecl *PatternDef = Pattern->getDefinition();
2146 if (DiagnoseUninstantiableTemplate(*this, PointOfInstantiation, Instantiation,
2147 Instantiation->getInstantiatedFromMemberEnum(),
2148 Pattern, PatternDef, TSK,/*Complain*/true))
2150 Pattern = PatternDef;
2152 // Record the point of instantiation.
2153 if (MemberSpecializationInfo *MSInfo
2154 = Instantiation->getMemberSpecializationInfo()) {
2155 MSInfo->setTemplateSpecializationKind(TSK);
2156 MSInfo->setPointOfInstantiation(PointOfInstantiation);
2159 InstantiatingTemplate Inst(*this, PointOfInstantiation, Instantiation);
2160 if (Inst.isInvalid())
2163 // The instantiation is visible here, even if it was first declared in an
2164 // unimported module.
2165 Instantiation->setHidden(false);
2167 // Enter the scope of this instantiation. We don't use
2168 // PushDeclContext because we don't have a scope.
2169 ContextRAII SavedContext(*this, Instantiation);
2170 EnterExpressionEvaluationContext EvalContext(*this,
2171 Sema::PotentiallyEvaluated);
2173 LocalInstantiationScope Scope(*this, /*MergeWithParentScope*/true);
2175 // Pull attributes from the pattern onto the instantiation.
2176 InstantiateAttrs(TemplateArgs, Pattern, Instantiation);
2178 TemplateDeclInstantiator Instantiator(*this, Instantiation, TemplateArgs);
2179 Instantiator.InstantiateEnumDefinition(Instantiation, Pattern);
2181 // Exit the scope of this instantiation.
2184 return Instantiation->isInvalidDecl();
2188 /// \brief Instantiate the definition of a field from the given pattern.
2190 /// \param PointOfInstantiation The point of instantiation within the
2192 /// \param Instantiation is the declaration whose definition is being
2193 /// instantiated. This will be a class of a class temploid
2194 /// specialization, or a local enumeration within a function temploid
2196 /// \param Pattern The templated declaration from which the instantiation
2198 /// \param TemplateArgs The template arguments to be substituted into
2201 /// \return \c true if an error occurred, \c false otherwise.
2202 bool Sema::InstantiateInClassInitializer(
2203 SourceLocation PointOfInstantiation, FieldDecl *Instantiation,
2204 FieldDecl *Pattern, const MultiLevelTemplateArgumentList &TemplateArgs) {
2205 // If there is no initializer, we don't need to do anything.
2206 if (!Pattern->hasInClassInitializer())
2209 assert(Instantiation->getInClassInitStyle() ==
2210 Pattern->getInClassInitStyle() &&
2211 "pattern and instantiation disagree about init style");
2213 // Error out if we haven't parsed the initializer of the pattern yet because
2214 // we are waiting for the closing brace of the outer class.
2215 Expr *OldInit = Pattern->getInClassInitializer();
2217 RecordDecl *PatternRD = Pattern->getParent();
2218 RecordDecl *OutermostClass = PatternRD->getOuterLexicalRecordContext();
2219 if (OutermostClass == PatternRD) {
2220 Diag(Pattern->getLocEnd(), diag::err_in_class_initializer_not_yet_parsed)
2221 << PatternRD << Pattern;
2223 Diag(Pattern->getLocEnd(),
2224 diag::err_in_class_initializer_not_yet_parsed_outer_class)
2225 << PatternRD << OutermostClass << Pattern;
2227 Instantiation->setInvalidDecl();
2231 InstantiatingTemplate Inst(*this, PointOfInstantiation, Instantiation);
2232 if (Inst.isInvalid())
2235 // Enter the scope of this instantiation. We don't use PushDeclContext because
2236 // we don't have a scope.
2237 ContextRAII SavedContext(*this, Instantiation->getParent());
2238 EnterExpressionEvaluationContext EvalContext(*this,
2239 Sema::PotentiallyEvaluated);
2241 LocalInstantiationScope Scope(*this, true);
2243 // Instantiate the initializer.
2244 ActOnStartCXXInClassMemberInitializer();
2245 CXXThisScopeRAII ThisScope(*this, Instantiation->getParent(), /*TypeQuals=*/0);
2247 ExprResult NewInit = SubstInitializer(OldInit, TemplateArgs,
2248 /*CXXDirectInit=*/false);
2249 Expr *Init = NewInit.get();
2250 assert((!Init || !isa<ParenListExpr>(Init)) && "call-style init in class");
2251 ActOnFinishCXXInClassMemberInitializer(
2252 Instantiation, Init ? Init->getLocStart() : SourceLocation(), Init);
2254 // Exit the scope of this instantiation.
2257 // Return true if the in-class initializer is still missing.
2258 return !Instantiation->getInClassInitializer();
2262 /// \brief A partial specialization whose template arguments have matched
2263 /// a given template-id.
2264 struct PartialSpecMatchResult {
2265 ClassTemplatePartialSpecializationDecl *Partial;
2266 TemplateArgumentList *Args;
2270 bool Sema::InstantiateClassTemplateSpecialization(
2271 SourceLocation PointOfInstantiation,
2272 ClassTemplateSpecializationDecl *ClassTemplateSpec,
2273 TemplateSpecializationKind TSK, bool Complain) {
2274 // Perform the actual instantiation on the canonical declaration.
2275 ClassTemplateSpec = cast<ClassTemplateSpecializationDecl>(
2276 ClassTemplateSpec->getCanonicalDecl());
2277 if (ClassTemplateSpec->isInvalidDecl())
2280 ClassTemplateDecl *Template = ClassTemplateSpec->getSpecializedTemplate();
2281 CXXRecordDecl *Pattern = nullptr;
2283 // C++ [temp.class.spec.match]p1:
2284 // When a class template is used in a context that requires an
2285 // instantiation of the class, it is necessary to determine
2286 // whether the instantiation is to be generated using the primary
2287 // template or one of the partial specializations. This is done by
2288 // matching the template arguments of the class template
2289 // specialization with the template argument lists of the partial
2291 typedef PartialSpecMatchResult MatchResult;
2292 SmallVector<MatchResult, 4> Matched;
2293 SmallVector<ClassTemplatePartialSpecializationDecl *, 4> PartialSpecs;
2294 Template->getPartialSpecializations(PartialSpecs);
2295 TemplateSpecCandidateSet FailedCandidates(PointOfInstantiation);
2296 for (unsigned I = 0, N = PartialSpecs.size(); I != N; ++I) {
2297 ClassTemplatePartialSpecializationDecl *Partial = PartialSpecs[I];
2298 TemplateDeductionInfo Info(FailedCandidates.getLocation());
2299 if (TemplateDeductionResult Result
2300 = DeduceTemplateArguments(Partial,
2301 ClassTemplateSpec->getTemplateArgs(),
2303 // Store the failed-deduction information for use in diagnostics, later.
2304 // TODO: Actually use the failed-deduction info?
2305 FailedCandidates.addCandidate()
2306 .set(Partial, MakeDeductionFailureInfo(Context, Result, Info));
2309 Matched.push_back(PartialSpecMatchResult());
2310 Matched.back().Partial = Partial;
2311 Matched.back().Args = Info.take();
2315 // If we're dealing with a member template where the template parameters
2316 // have been instantiated, this provides the original template parameters
2317 // from which the member template's parameters were instantiated.
2319 if (Matched.size() >= 1) {
2320 SmallVectorImpl<MatchResult>::iterator Best = Matched.begin();
2321 if (Matched.size() == 1) {
2322 // -- If exactly one matching specialization is found, the
2323 // instantiation is generated from that specialization.
2324 // We don't need to do anything for this.
2326 // -- If more than one matching specialization is found, the
2327 // partial order rules (14.5.4.2) are used to determine
2328 // whether one of the specializations is more specialized
2329 // than the others. If none of the specializations is more
2330 // specialized than all of the other matching
2331 // specializations, then the use of the class template is
2332 // ambiguous and the program is ill-formed.
2333 for (SmallVectorImpl<MatchResult>::iterator P = Best + 1,
2334 PEnd = Matched.end();
2336 if (getMoreSpecializedPartialSpecialization(P->Partial, Best->Partial,
2337 PointOfInstantiation)
2342 // Determine if the best partial specialization is more specialized than
2344 bool Ambiguous = false;
2345 for (SmallVectorImpl<MatchResult>::iterator P = Matched.begin(),
2346 PEnd = Matched.end();
2349 getMoreSpecializedPartialSpecialization(P->Partial, Best->Partial,
2350 PointOfInstantiation)
2358 // Partial ordering did not produce a clear winner. Complain.
2359 ClassTemplateSpec->setInvalidDecl();
2360 Diag(PointOfInstantiation, diag::err_partial_spec_ordering_ambiguous)
2361 << ClassTemplateSpec;
2363 // Print the matching partial specializations.
2364 for (SmallVectorImpl<MatchResult>::iterator P = Matched.begin(),
2365 PEnd = Matched.end();
2367 Diag(P->Partial->getLocation(), diag::note_partial_spec_match)
2368 << getTemplateArgumentBindingsText(
2369 P->Partial->getTemplateParameters(),
2376 // Instantiate using the best class template partial specialization.
2377 ClassTemplatePartialSpecializationDecl *OrigPartialSpec = Best->Partial;
2378 while (OrigPartialSpec->getInstantiatedFromMember()) {
2379 // If we've found an explicit specialization of this class template,
2380 // stop here and use that as the pattern.
2381 if (OrigPartialSpec->isMemberSpecialization())
2384 OrigPartialSpec = OrigPartialSpec->getInstantiatedFromMember();
2387 Pattern = OrigPartialSpec;
2388 ClassTemplateSpec->setInstantiationOf(Best->Partial, Best->Args);
2390 // -- If no matches are found, the instantiation is generated
2391 // from the primary template.
2392 ClassTemplateDecl *OrigTemplate = Template;
2393 while (OrigTemplate->getInstantiatedFromMemberTemplate()) {
2394 // If we've found an explicit specialization of this class template,
2395 // stop here and use that as the pattern.
2396 if (OrigTemplate->isMemberSpecialization())
2399 OrigTemplate = OrigTemplate->getInstantiatedFromMemberTemplate();
2402 Pattern = OrigTemplate->getTemplatedDecl();
2405 bool Result = InstantiateClass(PointOfInstantiation, ClassTemplateSpec,
2407 getTemplateInstantiationArgs(ClassTemplateSpec),
2414 /// \brief Instantiates the definitions of all of the member
2415 /// of the given class, which is an instantiation of a class template
2416 /// or a member class of a template.
2418 Sema::InstantiateClassMembers(SourceLocation PointOfInstantiation,
2419 CXXRecordDecl *Instantiation,
2420 const MultiLevelTemplateArgumentList &TemplateArgs,
2421 TemplateSpecializationKind TSK) {
2422 // FIXME: We need to notify the ASTMutationListener that we did all of these
2423 // things, in case we have an explicit instantiation definition in a PCM, a
2424 // module, or preamble, and the declaration is in an imported AST.
2426 (TSK == TSK_ExplicitInstantiationDefinition ||
2427 TSK == TSK_ExplicitInstantiationDeclaration ||
2428 (TSK == TSK_ImplicitInstantiation && Instantiation->isLocalClass())) &&
2429 "Unexpected template specialization kind!");
2430 for (auto *D : Instantiation->decls()) {
2431 bool SuppressNew = false;
2432 if (auto *Function = dyn_cast<FunctionDecl>(D)) {
2433 if (FunctionDecl *Pattern
2434 = Function->getInstantiatedFromMemberFunction()) {
2435 MemberSpecializationInfo *MSInfo
2436 = Function->getMemberSpecializationInfo();
2437 assert(MSInfo && "No member specialization information?");
2438 if (MSInfo->getTemplateSpecializationKind()
2439 == TSK_ExplicitSpecialization)
2442 if (CheckSpecializationInstantiationRedecl(PointOfInstantiation, TSK,
2444 MSInfo->getTemplateSpecializationKind(),
2445 MSInfo->getPointOfInstantiation(),
2450 // C++11 [temp.explicit]p8:
2451 // An explicit instantiation definition that names a class template
2452 // specialization explicitly instantiates the class template
2453 // specialization and is only an explicit instantiation definition
2454 // of members whose definition is visible at the point of
2456 if (TSK == TSK_ExplicitInstantiationDefinition && !Pattern->isDefined())
2459 Function->setTemplateSpecializationKind(TSK, PointOfInstantiation);
2461 if (Function->isDefined()) {
2462 // Let the ASTConsumer know that this function has been explicitly
2463 // instantiated now, and its linkage might have changed.
2464 Consumer.HandleTopLevelDecl(DeclGroupRef(Function));
2465 } else if (TSK == TSK_ExplicitInstantiationDefinition) {
2466 InstantiateFunctionDefinition(PointOfInstantiation, Function);
2467 } else if (TSK == TSK_ImplicitInstantiation) {
2468 PendingLocalImplicitInstantiations.push_back(
2469 std::make_pair(Function, PointOfInstantiation));
2472 } else if (auto *Var = dyn_cast<VarDecl>(D)) {
2473 if (isa<VarTemplateSpecializationDecl>(Var))
2476 if (Var->isStaticDataMember()) {
2477 MemberSpecializationInfo *MSInfo = Var->getMemberSpecializationInfo();
2478 assert(MSInfo && "No member specialization information?");
2479 if (MSInfo->getTemplateSpecializationKind()
2480 == TSK_ExplicitSpecialization)
2483 if (CheckSpecializationInstantiationRedecl(PointOfInstantiation, TSK,
2485 MSInfo->getTemplateSpecializationKind(),
2486 MSInfo->getPointOfInstantiation(),
2491 if (TSK == TSK_ExplicitInstantiationDefinition) {
2492 // C++0x [temp.explicit]p8:
2493 // An explicit instantiation definition that names a class template
2494 // specialization explicitly instantiates the class template
2495 // specialization and is only an explicit instantiation definition
2496 // of members whose definition is visible at the point of
2498 if (!Var->getInstantiatedFromStaticDataMember()
2499 ->getOutOfLineDefinition())
2502 Var->setTemplateSpecializationKind(TSK, PointOfInstantiation);
2503 InstantiateStaticDataMemberDefinition(PointOfInstantiation, Var);
2505 Var->setTemplateSpecializationKind(TSK, PointOfInstantiation);
2508 } else if (auto *Record = dyn_cast<CXXRecordDecl>(D)) {
2509 // Always skip the injected-class-name, along with any
2510 // redeclarations of nested classes, since both would cause us
2511 // to try to instantiate the members of a class twice.
2512 // Skip closure types; they'll get instantiated when we instantiate
2513 // the corresponding lambda-expression.
2514 if (Record->isInjectedClassName() || Record->getPreviousDecl() ||
2518 MemberSpecializationInfo *MSInfo = Record->getMemberSpecializationInfo();
2519 assert(MSInfo && "No member specialization information?");
2521 if (MSInfo->getTemplateSpecializationKind()
2522 == TSK_ExplicitSpecialization)
2525 if (CheckSpecializationInstantiationRedecl(PointOfInstantiation, TSK,
2527 MSInfo->getTemplateSpecializationKind(),
2528 MSInfo->getPointOfInstantiation(),
2533 CXXRecordDecl *Pattern = Record->getInstantiatedFromMemberClass();
2534 assert(Pattern && "Missing instantiated-from-template information");
2536 if (!Record->getDefinition()) {
2537 if (!Pattern->getDefinition()) {
2538 // C++0x [temp.explicit]p8:
2539 // An explicit instantiation definition that names a class template
2540 // specialization explicitly instantiates the class template
2541 // specialization and is only an explicit instantiation definition
2542 // of members whose definition is visible at the point of
2544 if (TSK == TSK_ExplicitInstantiationDeclaration) {
2545 MSInfo->setTemplateSpecializationKind(TSK);
2546 MSInfo->setPointOfInstantiation(PointOfInstantiation);
2552 InstantiateClass(PointOfInstantiation, Record, Pattern,
2556 if (TSK == TSK_ExplicitInstantiationDefinition &&
2557 Record->getTemplateSpecializationKind() ==
2558 TSK_ExplicitInstantiationDeclaration) {
2559 Record->setTemplateSpecializationKind(TSK);
2560 MarkVTableUsed(PointOfInstantiation, Record, true);
2564 Pattern = cast_or_null<CXXRecordDecl>(Record->getDefinition());
2566 InstantiateClassMembers(PointOfInstantiation, Pattern, TemplateArgs,
2568 } else if (auto *Enum = dyn_cast<EnumDecl>(D)) {
2569 MemberSpecializationInfo *MSInfo = Enum->getMemberSpecializationInfo();
2570 assert(MSInfo && "No member specialization information?");
2572 if (MSInfo->getTemplateSpecializationKind()
2573 == TSK_ExplicitSpecialization)
2576 if (CheckSpecializationInstantiationRedecl(
2577 PointOfInstantiation, TSK, Enum,
2578 MSInfo->getTemplateSpecializationKind(),
2579 MSInfo->getPointOfInstantiation(), SuppressNew) ||
2583 if (Enum->getDefinition())
2586 EnumDecl *Pattern = Enum->getInstantiatedFromMemberEnum();
2587 assert(Pattern && "Missing instantiated-from-template information");
2589 if (TSK == TSK_ExplicitInstantiationDefinition) {
2590 if (!Pattern->getDefinition())
2593 InstantiateEnum(PointOfInstantiation, Enum, Pattern, TemplateArgs, TSK);
2595 MSInfo->setTemplateSpecializationKind(TSK);
2596 MSInfo->setPointOfInstantiation(PointOfInstantiation);
2598 } else if (auto *Field = dyn_cast<FieldDecl>(D)) {
2599 // No need to instantiate in-class initializers during explicit
2601 if (Field->hasInClassInitializer() && TSK == TSK_ImplicitInstantiation) {
2602 CXXRecordDecl *ClassPattern =
2603 Instantiation->getTemplateInstantiationPattern();
2604 DeclContext::lookup_result Lookup =
2605 ClassPattern->lookup(Field->getDeclName());
2606 assert(Lookup.size() == 1);
2607 FieldDecl *Pattern = cast<FieldDecl>(Lookup[0]);
2608 InstantiateInClassInitializer(PointOfInstantiation, Field, Pattern,
2615 /// \brief Instantiate the definitions of all of the members of the
2616 /// given class template specialization, which was named as part of an
2617 /// explicit instantiation.
2619 Sema::InstantiateClassTemplateSpecializationMembers(
2620 SourceLocation PointOfInstantiation,
2621 ClassTemplateSpecializationDecl *ClassTemplateSpec,
2622 TemplateSpecializationKind TSK) {
2623 // C++0x [temp.explicit]p7:
2624 // An explicit instantiation that names a class template
2625 // specialization is an explicit instantion of the same kind
2626 // (declaration or definition) of each of its members (not
2627 // including members inherited from base classes) that has not
2628 // been previously explicitly specialized in the translation unit
2629 // containing the explicit instantiation, except as described
2631 InstantiateClassMembers(PointOfInstantiation, ClassTemplateSpec,
2632 getTemplateInstantiationArgs(ClassTemplateSpec),
2637 Sema::SubstStmt(Stmt *S, const MultiLevelTemplateArgumentList &TemplateArgs) {
2641 TemplateInstantiator Instantiator(*this, TemplateArgs,
2644 return Instantiator.TransformStmt(S);
2648 Sema::SubstExpr(Expr *E, const MultiLevelTemplateArgumentList &TemplateArgs) {
2652 TemplateInstantiator Instantiator(*this, TemplateArgs,
2655 return Instantiator.TransformExpr(E);
2658 ExprResult Sema::SubstInitializer(Expr *Init,
2659 const MultiLevelTemplateArgumentList &TemplateArgs,
2660 bool CXXDirectInit) {
2661 TemplateInstantiator Instantiator(*this, TemplateArgs,
2664 return Instantiator.TransformInitializer(Init, CXXDirectInit);
2667 bool Sema::SubstExprs(ArrayRef<Expr *> Exprs, bool IsCall,
2668 const MultiLevelTemplateArgumentList &TemplateArgs,
2669 SmallVectorImpl<Expr *> &Outputs) {
2673 TemplateInstantiator Instantiator(*this, TemplateArgs,
2676 return Instantiator.TransformExprs(Exprs.data(), Exprs.size(),
2680 NestedNameSpecifierLoc
2681 Sema::SubstNestedNameSpecifierLoc(NestedNameSpecifierLoc NNS,
2682 const MultiLevelTemplateArgumentList &TemplateArgs) {
2684 return NestedNameSpecifierLoc();
2686 TemplateInstantiator Instantiator(*this, TemplateArgs, NNS.getBeginLoc(),
2688 return Instantiator.TransformNestedNameSpecifierLoc(NNS);
2691 /// \brief Do template substitution on declaration name info.
2693 Sema::SubstDeclarationNameInfo(const DeclarationNameInfo &NameInfo,
2694 const MultiLevelTemplateArgumentList &TemplateArgs) {
2695 TemplateInstantiator Instantiator(*this, TemplateArgs, NameInfo.getLoc(),
2696 NameInfo.getName());
2697 return Instantiator.TransformDeclarationNameInfo(NameInfo);
2701 Sema::SubstTemplateName(NestedNameSpecifierLoc QualifierLoc,
2702 TemplateName Name, SourceLocation Loc,
2703 const MultiLevelTemplateArgumentList &TemplateArgs) {
2704 TemplateInstantiator Instantiator(*this, TemplateArgs, Loc,
2707 SS.Adopt(QualifierLoc);
2708 return Instantiator.TransformTemplateName(SS, Name, Loc);
2711 bool Sema::Subst(const TemplateArgumentLoc *Args, unsigned NumArgs,
2712 TemplateArgumentListInfo &Result,
2713 const MultiLevelTemplateArgumentList &TemplateArgs) {
2714 TemplateInstantiator Instantiator(*this, TemplateArgs, SourceLocation(),
2717 return Instantiator.TransformTemplateArguments(Args, NumArgs, Result);
2720 static const Decl *getCanonicalParmVarDecl(const Decl *D) {
2721 // When storing ParmVarDecls in the local instantiation scope, we always
2722 // want to use the ParmVarDecl from the canonical function declaration,
2723 // since the map is then valid for any redeclaration or definition of that
2725 if (const ParmVarDecl *PV = dyn_cast<ParmVarDecl>(D)) {
2726 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(PV->getDeclContext())) {
2727 unsigned i = PV->getFunctionScopeIndex();
2728 // This parameter might be from a freestanding function type within the
2729 // function and isn't necessarily referring to one of FD's parameters.
2730 if (FD->getParamDecl(i) == PV)
2731 return FD->getCanonicalDecl()->getParamDecl(i);
2738 llvm::PointerUnion<Decl *, LocalInstantiationScope::DeclArgumentPack *> *
2739 LocalInstantiationScope::findInstantiationOf(const Decl *D) {
2740 D = getCanonicalParmVarDecl(D);
2741 for (LocalInstantiationScope *Current = this; Current;
2742 Current = Current->Outer) {
2744 // Check if we found something within this scope.
2745 const Decl *CheckD = D;
2747 LocalDeclsMap::iterator Found = Current->LocalDecls.find(CheckD);
2748 if (Found != Current->LocalDecls.end())
2749 return &Found->second;
2751 // If this is a tag declaration, it's possible that we need to look for
2752 // a previous declaration.
2753 if (const TagDecl *Tag = dyn_cast<TagDecl>(CheckD))
2754 CheckD = Tag->getPreviousDecl();
2759 // If we aren't combined with our outer scope, we're done.
2760 if (!Current->CombineWithOuterScope)
2764 // If we're performing a partial substitution during template argument
2765 // deduction, we may not have values for template parameters yet.
2766 if (isa<NonTypeTemplateParmDecl>(D) || isa<TemplateTypeParmDecl>(D) ||
2767 isa<TemplateTemplateParmDecl>(D))
2770 // Local types referenced prior to definition may require instantiation.
2771 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(D))
2772 if (RD->isLocalClass())
2775 // Enumeration types referenced prior to definition may appear as a result of
2777 if (isa<EnumDecl>(D))
2780 // If we didn't find the decl, then we either have a sema bug, or we have a
2781 // forward reference to a label declaration. Return null to indicate that
2782 // we have an uninstantiated label.
2783 assert(isa<LabelDecl>(D) && "declaration not instantiated in this scope");
2787 void LocalInstantiationScope::InstantiatedLocal(const Decl *D, Decl *Inst) {
2788 D = getCanonicalParmVarDecl(D);
2789 llvm::PointerUnion<Decl *, DeclArgumentPack *> &Stored = LocalDecls[D];
2790 if (Stored.isNull()) {
2792 // It should not be present in any surrounding scope either.
2793 LocalInstantiationScope *Current = this;
2794 while (Current->CombineWithOuterScope && Current->Outer) {
2795 Current = Current->Outer;
2796 assert(Current->LocalDecls.find(D) == Current->LocalDecls.end() &&
2797 "Instantiated local in inner and outer scopes");
2801 } else if (DeclArgumentPack *Pack = Stored.dyn_cast<DeclArgumentPack *>()) {
2802 Pack->push_back(cast<ParmVarDecl>(Inst));
2804 assert(Stored.get<Decl *>() == Inst && "Already instantiated this local");
2808 void LocalInstantiationScope::InstantiatedLocalPackArg(const Decl *D,
2809 ParmVarDecl *Inst) {
2810 D = getCanonicalParmVarDecl(D);
2811 DeclArgumentPack *Pack = LocalDecls[D].get<DeclArgumentPack *>();
2812 Pack->push_back(Inst);
2815 void LocalInstantiationScope::MakeInstantiatedLocalArgPack(const Decl *D) {
2817 // This should be the first time we've been told about this decl.
2818 for (LocalInstantiationScope *Current = this;
2819 Current && Current->CombineWithOuterScope; Current = Current->Outer)
2820 assert(Current->LocalDecls.find(D) == Current->LocalDecls.end() &&
2821 "Creating local pack after instantiation of local");
2824 D = getCanonicalParmVarDecl(D);
2825 llvm::PointerUnion<Decl *, DeclArgumentPack *> &Stored = LocalDecls[D];
2826 DeclArgumentPack *Pack = new DeclArgumentPack;
2828 ArgumentPacks.push_back(Pack);
2831 void LocalInstantiationScope::SetPartiallySubstitutedPack(NamedDecl *Pack,
2832 const TemplateArgument *ExplicitArgs,
2833 unsigned NumExplicitArgs) {
2834 assert((!PartiallySubstitutedPack || PartiallySubstitutedPack == Pack) &&
2835 "Already have a partially-substituted pack");
2836 assert((!PartiallySubstitutedPack
2837 || NumArgsInPartiallySubstitutedPack == NumExplicitArgs) &&
2838 "Wrong number of arguments in partially-substituted pack");
2839 PartiallySubstitutedPack = Pack;
2840 ArgsInPartiallySubstitutedPack = ExplicitArgs;
2841 NumArgsInPartiallySubstitutedPack = NumExplicitArgs;
2844 NamedDecl *LocalInstantiationScope::getPartiallySubstitutedPack(
2845 const TemplateArgument **ExplicitArgs,
2846 unsigned *NumExplicitArgs) const {
2848 *ExplicitArgs = nullptr;
2849 if (NumExplicitArgs)
2850 *NumExplicitArgs = 0;
2852 for (const LocalInstantiationScope *Current = this; Current;
2853 Current = Current->Outer) {
2854 if (Current->PartiallySubstitutedPack) {
2856 *ExplicitArgs = Current->ArgsInPartiallySubstitutedPack;
2857 if (NumExplicitArgs)
2858 *NumExplicitArgs = Current->NumArgsInPartiallySubstitutedPack;
2860 return Current->PartiallySubstitutedPack;
2863 if (!Current->CombineWithOuterScope)