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/ASTMutationListener.h"
19 #include "clang/AST/DeclTemplate.h"
20 #include "clang/AST/Expr.h"
21 #include "clang/Basic/LangOptions.h"
22 #include "clang/Sema/DeclSpec.h"
23 #include "clang/Sema/Initialization.h"
24 #include "clang/Sema/Lookup.h"
25 #include "clang/Sema/PrettyDeclStackTrace.h"
26 #include "clang/Sema/Template.h"
27 #include "clang/Sema/TemplateDeduction.h"
29 using namespace clang;
32 //===----------------------------------------------------------------------===/
33 // Template Instantiation Support
34 //===----------------------------------------------------------------------===/
36 /// \brief Retrieve the template argument list(s) that should be used to
37 /// instantiate the definition of the given declaration.
39 /// \param D the declaration for which we are computing template instantiation
42 /// \param Innermost if non-NULL, the innermost template argument list.
44 /// \param RelativeToPrimary true if we should get the template
45 /// arguments relative to the primary template, even when we're
46 /// dealing with a specialization. This is only relevant for function
47 /// template specializations.
49 /// \param Pattern If non-NULL, indicates the pattern from which we will be
50 /// instantiating the definition of the given declaration, \p D. This is
51 /// used to determine the proper set of template instantiation arguments for
52 /// friend function template specializations.
53 MultiLevelTemplateArgumentList
54 Sema::getTemplateInstantiationArgs(NamedDecl *D,
55 const TemplateArgumentList *Innermost,
56 bool RelativeToPrimary,
57 const FunctionDecl *Pattern) {
58 // Accumulate the set of template argument lists in this structure.
59 MultiLevelTemplateArgumentList Result;
62 Result.addOuterTemplateArguments(Innermost);
64 DeclContext *Ctx = dyn_cast<DeclContext>(D);
66 Ctx = D->getDeclContext();
68 // Add template arguments from a variable template instantiation.
69 if (VarTemplateSpecializationDecl *Spec =
70 dyn_cast<VarTemplateSpecializationDecl>(D)) {
71 // We're done when we hit an explicit specialization.
72 if (Spec->getSpecializationKind() == TSK_ExplicitSpecialization &&
73 !isa<VarTemplatePartialSpecializationDecl>(Spec))
76 Result.addOuterTemplateArguments(&Spec->getTemplateInstantiationArgs());
78 // If this variable template specialization was instantiated from a
79 // specialized member that is a variable template, we're done.
80 assert(Spec->getSpecializedTemplate() && "No variable template?");
81 llvm::PointerUnion<VarTemplateDecl*,
82 VarTemplatePartialSpecializationDecl*> Specialized
83 = Spec->getSpecializedTemplateOrPartial();
84 if (VarTemplatePartialSpecializationDecl *Partial =
85 Specialized.dyn_cast<VarTemplatePartialSpecializationDecl *>()) {
86 if (Partial->isMemberSpecialization())
89 VarTemplateDecl *Tmpl = Specialized.get<VarTemplateDecl *>();
90 if (Tmpl->isMemberSpecialization())
95 // If we have a template template parameter with translation unit context,
96 // then we're performing substitution into a default template argument of
97 // this template template parameter before we've constructed the template
98 // that will own this template template parameter. In this case, we
99 // use empty template parameter lists for all of the outer templates
100 // to avoid performing any substitutions.
101 if (Ctx->isTranslationUnit()) {
102 if (TemplateTemplateParmDecl *TTP
103 = dyn_cast<TemplateTemplateParmDecl>(D)) {
104 for (unsigned I = 0, N = TTP->getDepth() + 1; I != N; ++I)
105 Result.addOuterTemplateArguments(None);
111 while (!Ctx->isFileContext()) {
112 // Add template arguments from a class template instantiation.
113 if (ClassTemplateSpecializationDecl *Spec
114 = dyn_cast<ClassTemplateSpecializationDecl>(Ctx)) {
115 // We're done when we hit an explicit specialization.
116 if (Spec->getSpecializationKind() == TSK_ExplicitSpecialization &&
117 !isa<ClassTemplatePartialSpecializationDecl>(Spec))
120 Result.addOuterTemplateArguments(&Spec->getTemplateInstantiationArgs());
122 // If this class template specialization was instantiated from a
123 // specialized member that is a class template, we're done.
124 assert(Spec->getSpecializedTemplate() && "No class template?");
125 if (Spec->getSpecializedTemplate()->isMemberSpecialization())
128 // Add template arguments from a function template specialization.
129 else if (FunctionDecl *Function = dyn_cast<FunctionDecl>(Ctx)) {
130 if (!RelativeToPrimary &&
131 (Function->getTemplateSpecializationKind() ==
132 TSK_ExplicitSpecialization &&
133 !Function->getClassScopeSpecializationPattern()))
136 if (const TemplateArgumentList *TemplateArgs
137 = Function->getTemplateSpecializationArgs()) {
138 // Add the template arguments for this specialization.
139 Result.addOuterTemplateArguments(TemplateArgs);
141 // If this function was instantiated from a specialized member that is
142 // a function template, we're done.
143 assert(Function->getPrimaryTemplate() && "No function template?");
144 if (Function->getPrimaryTemplate()->isMemberSpecialization())
147 // If this function is a generic lambda specialization, we are done.
148 if (isGenericLambdaCallOperatorSpecialization(Function))
151 } else if (FunctionTemplateDecl *FunTmpl
152 = Function->getDescribedFunctionTemplate()) {
153 // Add the "injected" template arguments.
154 Result.addOuterTemplateArguments(FunTmpl->getInjectedTemplateArgs());
157 // If this is a friend declaration and it declares an entity at
158 // namespace scope, take arguments from its lexical parent
159 // instead of its semantic parent, unless of course the pattern we're
160 // instantiating actually comes from the file's context!
161 if (Function->getFriendObjectKind() &&
162 Function->getDeclContext()->isFileContext() &&
163 (!Pattern || !Pattern->getLexicalDeclContext()->isFileContext())) {
164 Ctx = Function->getLexicalDeclContext();
165 RelativeToPrimary = false;
168 } else if (CXXRecordDecl *Rec = dyn_cast<CXXRecordDecl>(Ctx)) {
169 if (ClassTemplateDecl *ClassTemplate = Rec->getDescribedClassTemplate()) {
170 QualType T = ClassTemplate->getInjectedClassNameSpecialization();
171 const TemplateSpecializationType *TST =
172 cast<TemplateSpecializationType>(Context.getCanonicalType(T));
173 Result.addOuterTemplateArguments(
174 llvm::makeArrayRef(TST->getArgs(), TST->getNumArgs()));
175 if (ClassTemplate->isMemberSpecialization())
180 Ctx = Ctx->getParent();
181 RelativeToPrimary = false;
187 bool Sema::ActiveTemplateInstantiation::isInstantiationRecord() const {
189 case TemplateInstantiation:
190 case ExceptionSpecInstantiation:
191 case DefaultTemplateArgumentInstantiation:
192 case DefaultFunctionArgumentInstantiation:
193 case ExplicitTemplateArgumentSubstitution:
194 case DeducedTemplateArgumentSubstitution:
195 case PriorTemplateArgumentSubstitution:
198 case DefaultTemplateArgumentChecking:
202 llvm_unreachable("Invalid InstantiationKind!");
205 Sema::InstantiatingTemplate::InstantiatingTemplate(
206 Sema &SemaRef, ActiveTemplateInstantiation::InstantiationKind Kind,
207 SourceLocation PointOfInstantiation, SourceRange InstantiationRange,
208 Decl *Entity, NamedDecl *Template, ArrayRef<TemplateArgument> TemplateArgs,
209 sema::TemplateDeductionInfo *DeductionInfo)
210 : SemaRef(SemaRef), SavedInNonInstantiationSFINAEContext(
211 SemaRef.InNonInstantiationSFINAEContext) {
212 // Don't allow further instantiation if a fatal error and an uncompilable
213 // error have occurred. Any diagnostics we might have raised will not be
214 // visible, and we do not need to construct a correct AST.
215 if (SemaRef.Diags.hasFatalErrorOccurred() &&
216 SemaRef.Diags.hasUncompilableErrorOccurred()) {
220 Invalid = CheckInstantiationDepth(PointOfInstantiation, InstantiationRange);
222 ActiveTemplateInstantiation Inst;
224 Inst.PointOfInstantiation = PointOfInstantiation;
225 Inst.Entity = Entity;
226 Inst.Template = Template;
227 Inst.TemplateArgs = TemplateArgs.data();
228 Inst.NumTemplateArgs = TemplateArgs.size();
229 Inst.DeductionInfo = DeductionInfo;
230 Inst.InstantiationRange = InstantiationRange;
231 AlreadyInstantiating =
232 !SemaRef.InstantiatingSpecializations
233 .insert(std::make_pair(Inst.Entity->getCanonicalDecl(), Inst.Kind))
235 SemaRef.InNonInstantiationSFINAEContext = false;
236 SemaRef.ActiveTemplateInstantiations.push_back(Inst);
237 if (!Inst.isInstantiationRecord())
238 ++SemaRef.NonInstantiationEntries;
242 Sema::InstantiatingTemplate::InstantiatingTemplate(
243 Sema &SemaRef, SourceLocation PointOfInstantiation, Decl *Entity,
244 SourceRange InstantiationRange)
245 : InstantiatingTemplate(SemaRef,
246 ActiveTemplateInstantiation::TemplateInstantiation,
247 PointOfInstantiation, InstantiationRange, Entity) {}
249 Sema::InstantiatingTemplate::InstantiatingTemplate(
250 Sema &SemaRef, SourceLocation PointOfInstantiation, FunctionDecl *Entity,
251 ExceptionSpecification, SourceRange InstantiationRange)
252 : InstantiatingTemplate(
253 SemaRef, ActiveTemplateInstantiation::ExceptionSpecInstantiation,
254 PointOfInstantiation, InstantiationRange, Entity) {}
256 Sema::InstantiatingTemplate::InstantiatingTemplate(
257 Sema &SemaRef, SourceLocation PointOfInstantiation, TemplateParameter Param,
258 TemplateDecl *Template, ArrayRef<TemplateArgument> TemplateArgs,
259 SourceRange InstantiationRange)
260 : InstantiatingTemplate(
262 ActiveTemplateInstantiation::DefaultTemplateArgumentInstantiation,
263 PointOfInstantiation, InstantiationRange, getAsNamedDecl(Param),
264 Template, TemplateArgs) {}
266 Sema::InstantiatingTemplate::InstantiatingTemplate(
267 Sema &SemaRef, SourceLocation PointOfInstantiation,
268 FunctionTemplateDecl *FunctionTemplate,
269 ArrayRef<TemplateArgument> TemplateArgs,
270 ActiveTemplateInstantiation::InstantiationKind Kind,
271 sema::TemplateDeductionInfo &DeductionInfo, SourceRange InstantiationRange)
272 : InstantiatingTemplate(SemaRef, Kind, PointOfInstantiation,
273 InstantiationRange, FunctionTemplate, nullptr,
274 TemplateArgs, &DeductionInfo) {
276 Kind == ActiveTemplateInstantiation::ExplicitTemplateArgumentSubstitution ||
277 Kind == ActiveTemplateInstantiation::DeducedTemplateArgumentSubstitution);
280 Sema::InstantiatingTemplate::InstantiatingTemplate(
281 Sema &SemaRef, SourceLocation PointOfInstantiation,
282 TemplateDecl *Template,
283 ArrayRef<TemplateArgument> TemplateArgs,
284 sema::TemplateDeductionInfo &DeductionInfo, SourceRange InstantiationRange)
285 : InstantiatingTemplate(
287 ActiveTemplateInstantiation::DeducedTemplateArgumentSubstitution,
288 PointOfInstantiation, InstantiationRange, Template, nullptr,
289 TemplateArgs, &DeductionInfo) {}
291 Sema::InstantiatingTemplate::InstantiatingTemplate(
292 Sema &SemaRef, SourceLocation PointOfInstantiation,
293 ClassTemplatePartialSpecializationDecl *PartialSpec,
294 ArrayRef<TemplateArgument> TemplateArgs,
295 sema::TemplateDeductionInfo &DeductionInfo, SourceRange InstantiationRange)
296 : InstantiatingTemplate(
298 ActiveTemplateInstantiation::DeducedTemplateArgumentSubstitution,
299 PointOfInstantiation, InstantiationRange, PartialSpec, nullptr,
300 TemplateArgs, &DeductionInfo) {}
302 Sema::InstantiatingTemplate::InstantiatingTemplate(
303 Sema &SemaRef, SourceLocation PointOfInstantiation,
304 VarTemplatePartialSpecializationDecl *PartialSpec,
305 ArrayRef<TemplateArgument> TemplateArgs,
306 sema::TemplateDeductionInfo &DeductionInfo, SourceRange InstantiationRange)
307 : InstantiatingTemplate(
309 ActiveTemplateInstantiation::DeducedTemplateArgumentSubstitution,
310 PointOfInstantiation, InstantiationRange, PartialSpec, nullptr,
311 TemplateArgs, &DeductionInfo) {}
313 Sema::InstantiatingTemplate::InstantiatingTemplate(
314 Sema &SemaRef, SourceLocation PointOfInstantiation, ParmVarDecl *Param,
315 ArrayRef<TemplateArgument> TemplateArgs, SourceRange InstantiationRange)
316 : InstantiatingTemplate(
318 ActiveTemplateInstantiation::DefaultFunctionArgumentInstantiation,
319 PointOfInstantiation, InstantiationRange, Param, nullptr,
322 Sema::InstantiatingTemplate::InstantiatingTemplate(
323 Sema &SemaRef, SourceLocation PointOfInstantiation, NamedDecl *Template,
324 NonTypeTemplateParmDecl *Param, ArrayRef<TemplateArgument> TemplateArgs,
325 SourceRange InstantiationRange)
326 : InstantiatingTemplate(
328 ActiveTemplateInstantiation::PriorTemplateArgumentSubstitution,
329 PointOfInstantiation, InstantiationRange, Param, Template,
332 Sema::InstantiatingTemplate::InstantiatingTemplate(
333 Sema &SemaRef, SourceLocation PointOfInstantiation, NamedDecl *Template,
334 TemplateTemplateParmDecl *Param, ArrayRef<TemplateArgument> TemplateArgs,
335 SourceRange InstantiationRange)
336 : InstantiatingTemplate(
338 ActiveTemplateInstantiation::PriorTemplateArgumentSubstitution,
339 PointOfInstantiation, InstantiationRange, Param, Template,
342 Sema::InstantiatingTemplate::InstantiatingTemplate(
343 Sema &SemaRef, SourceLocation PointOfInstantiation, TemplateDecl *Template,
344 NamedDecl *Param, ArrayRef<TemplateArgument> TemplateArgs,
345 SourceRange InstantiationRange)
346 : InstantiatingTemplate(
347 SemaRef, ActiveTemplateInstantiation::DefaultTemplateArgumentChecking,
348 PointOfInstantiation, InstantiationRange, Param, Template,
351 void Sema::InstantiatingTemplate::Clear() {
353 auto &Active = SemaRef.ActiveTemplateInstantiations.back();
354 if (!Active.isInstantiationRecord()) {
355 assert(SemaRef.NonInstantiationEntries > 0);
356 --SemaRef.NonInstantiationEntries;
358 SemaRef.InNonInstantiationSFINAEContext
359 = SavedInNonInstantiationSFINAEContext;
361 // Name lookup no longer looks in this template's defining module.
362 assert(SemaRef.ActiveTemplateInstantiations.size() >=
363 SemaRef.ActiveTemplateInstantiationLookupModules.size() &&
364 "forgot to remove a lookup module for a template instantiation");
365 if (SemaRef.ActiveTemplateInstantiations.size() ==
366 SemaRef.ActiveTemplateInstantiationLookupModules.size()) {
367 if (Module *M = SemaRef.ActiveTemplateInstantiationLookupModules.back())
368 SemaRef.LookupModulesCache.erase(M);
369 SemaRef.ActiveTemplateInstantiationLookupModules.pop_back();
372 if (!AlreadyInstantiating)
373 SemaRef.InstantiatingSpecializations.erase(
374 std::make_pair(Active.Entity, Active.Kind));
376 SemaRef.ActiveTemplateInstantiations.pop_back();
381 bool Sema::InstantiatingTemplate::CheckInstantiationDepth(
382 SourceLocation PointOfInstantiation,
383 SourceRange InstantiationRange) {
384 assert(SemaRef.NonInstantiationEntries <=
385 SemaRef.ActiveTemplateInstantiations.size());
386 if ((SemaRef.ActiveTemplateInstantiations.size() -
387 SemaRef.NonInstantiationEntries)
388 <= SemaRef.getLangOpts().InstantiationDepth)
391 SemaRef.Diag(PointOfInstantiation,
392 diag::err_template_recursion_depth_exceeded)
393 << SemaRef.getLangOpts().InstantiationDepth
394 << InstantiationRange;
395 SemaRef.Diag(PointOfInstantiation, diag::note_template_recursion_depth)
396 << SemaRef.getLangOpts().InstantiationDepth;
400 /// \brief Prints the current instantiation stack through a series of
402 void Sema::PrintInstantiationStack() {
403 // Determine which template instantiations to skip, if any.
404 unsigned SkipStart = ActiveTemplateInstantiations.size(), SkipEnd = SkipStart;
405 unsigned Limit = Diags.getTemplateBacktraceLimit();
406 if (Limit && Limit < ActiveTemplateInstantiations.size()) {
407 SkipStart = Limit / 2 + Limit % 2;
408 SkipEnd = ActiveTemplateInstantiations.size() - Limit / 2;
411 // FIXME: In all of these cases, we need to show the template arguments
412 unsigned InstantiationIdx = 0;
413 for (SmallVectorImpl<ActiveTemplateInstantiation>::reverse_iterator
414 Active = ActiveTemplateInstantiations.rbegin(),
415 ActiveEnd = ActiveTemplateInstantiations.rend();
417 ++Active, ++InstantiationIdx) {
418 // Skip this instantiation?
419 if (InstantiationIdx >= SkipStart && InstantiationIdx < SkipEnd) {
420 if (InstantiationIdx == SkipStart) {
421 // Note that we're skipping instantiations.
422 Diags.Report(Active->PointOfInstantiation,
423 diag::note_instantiation_contexts_suppressed)
424 << unsigned(ActiveTemplateInstantiations.size() - Limit);
429 switch (Active->Kind) {
430 case ActiveTemplateInstantiation::TemplateInstantiation: {
431 Decl *D = Active->Entity;
432 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(D)) {
433 unsigned DiagID = diag::note_template_member_class_here;
434 if (isa<ClassTemplateSpecializationDecl>(Record))
435 DiagID = diag::note_template_class_instantiation_here;
436 Diags.Report(Active->PointOfInstantiation, DiagID)
437 << Record << Active->InstantiationRange;
438 } else if (FunctionDecl *Function = dyn_cast<FunctionDecl>(D)) {
440 if (Function->getPrimaryTemplate())
441 DiagID = diag::note_function_template_spec_here;
443 DiagID = diag::note_template_member_function_here;
444 Diags.Report(Active->PointOfInstantiation, DiagID)
446 << Active->InstantiationRange;
447 } else if (VarDecl *VD = dyn_cast<VarDecl>(D)) {
448 Diags.Report(Active->PointOfInstantiation,
449 VD->isStaticDataMember()?
450 diag::note_template_static_data_member_def_here
451 : diag::note_template_variable_def_here)
453 << Active->InstantiationRange;
454 } else if (EnumDecl *ED = dyn_cast<EnumDecl>(D)) {
455 Diags.Report(Active->PointOfInstantiation,
456 diag::note_template_enum_def_here)
458 << Active->InstantiationRange;
459 } else if (FieldDecl *FD = dyn_cast<FieldDecl>(D)) {
460 Diags.Report(Active->PointOfInstantiation,
461 diag::note_template_nsdmi_here)
462 << FD << Active->InstantiationRange;
464 Diags.Report(Active->PointOfInstantiation,
465 diag::note_template_type_alias_instantiation_here)
466 << cast<TypeAliasTemplateDecl>(D)
467 << Active->InstantiationRange;
472 case ActiveTemplateInstantiation::DefaultTemplateArgumentInstantiation: {
473 TemplateDecl *Template = cast<TemplateDecl>(Active->Template);
474 SmallVector<char, 128> TemplateArgsStr;
475 llvm::raw_svector_ostream OS(TemplateArgsStr);
476 Template->printName(OS);
477 TemplateSpecializationType::PrintTemplateArgumentList(
478 OS, Active->template_arguments(), getPrintingPolicy());
479 Diags.Report(Active->PointOfInstantiation,
480 diag::note_default_arg_instantiation_here)
482 << Active->InstantiationRange;
486 case ActiveTemplateInstantiation::ExplicitTemplateArgumentSubstitution: {
487 FunctionTemplateDecl *FnTmpl = cast<FunctionTemplateDecl>(Active->Entity);
488 Diags.Report(Active->PointOfInstantiation,
489 diag::note_explicit_template_arg_substitution_here)
491 << getTemplateArgumentBindingsText(FnTmpl->getTemplateParameters(),
492 Active->TemplateArgs,
493 Active->NumTemplateArgs)
494 << Active->InstantiationRange;
498 case ActiveTemplateInstantiation::DeducedTemplateArgumentSubstitution: {
499 if (FunctionTemplateDecl *FnTmpl =
500 dyn_cast<FunctionTemplateDecl>(Active->Entity)) {
501 Diags.Report(Active->PointOfInstantiation,
502 diag::note_function_template_deduction_instantiation_here)
504 << getTemplateArgumentBindingsText(FnTmpl->getTemplateParameters(),
505 Active->TemplateArgs,
506 Active->NumTemplateArgs)
507 << Active->InstantiationRange;
509 bool IsVar = isa<VarTemplateDecl>(Active->Entity) ||
510 isa<VarTemplateSpecializationDecl>(Active->Entity);
511 bool IsTemplate = false;
512 TemplateParameterList *Params;
513 if (auto *D = dyn_cast<TemplateDecl>(Active->Entity)) {
515 Params = D->getTemplateParameters();
516 } else if (auto *D = dyn_cast<ClassTemplatePartialSpecializationDecl>(
518 Params = D->getTemplateParameters();
519 } else if (auto *D = dyn_cast<VarTemplatePartialSpecializationDecl>(
521 Params = D->getTemplateParameters();
523 llvm_unreachable("unexpected template kind");
526 Diags.Report(Active->PointOfInstantiation,
527 diag::note_deduced_template_arg_substitution_here)
528 << IsVar << IsTemplate << cast<NamedDecl>(Active->Entity)
529 << getTemplateArgumentBindingsText(Params, Active->TemplateArgs,
530 Active->NumTemplateArgs)
531 << Active->InstantiationRange;
536 case ActiveTemplateInstantiation::DefaultFunctionArgumentInstantiation: {
537 ParmVarDecl *Param = cast<ParmVarDecl>(Active->Entity);
538 FunctionDecl *FD = cast<FunctionDecl>(Param->getDeclContext());
540 SmallVector<char, 128> TemplateArgsStr;
541 llvm::raw_svector_ostream OS(TemplateArgsStr);
543 TemplateSpecializationType::PrintTemplateArgumentList(
544 OS, Active->template_arguments(), getPrintingPolicy());
545 Diags.Report(Active->PointOfInstantiation,
546 diag::note_default_function_arg_instantiation_here)
548 << Active->InstantiationRange;
552 case ActiveTemplateInstantiation::PriorTemplateArgumentSubstitution: {
553 NamedDecl *Parm = cast<NamedDecl>(Active->Entity);
555 if (!Parm->getName().empty())
556 Name = std::string(" '") + Parm->getName().str() + "'";
558 TemplateParameterList *TemplateParams = nullptr;
559 if (TemplateDecl *Template = dyn_cast<TemplateDecl>(Active->Template))
560 TemplateParams = Template->getTemplateParameters();
563 cast<ClassTemplatePartialSpecializationDecl>(Active->Template)
564 ->getTemplateParameters();
565 Diags.Report(Active->PointOfInstantiation,
566 diag::note_prior_template_arg_substitution)
567 << isa<TemplateTemplateParmDecl>(Parm)
569 << getTemplateArgumentBindingsText(TemplateParams,
570 Active->TemplateArgs,
571 Active->NumTemplateArgs)
572 << Active->InstantiationRange;
576 case ActiveTemplateInstantiation::DefaultTemplateArgumentChecking: {
577 TemplateParameterList *TemplateParams = nullptr;
578 if (TemplateDecl *Template = dyn_cast<TemplateDecl>(Active->Template))
579 TemplateParams = Template->getTemplateParameters();
582 cast<ClassTemplatePartialSpecializationDecl>(Active->Template)
583 ->getTemplateParameters();
585 Diags.Report(Active->PointOfInstantiation,
586 diag::note_template_default_arg_checking)
587 << getTemplateArgumentBindingsText(TemplateParams,
588 Active->TemplateArgs,
589 Active->NumTemplateArgs)
590 << Active->InstantiationRange;
594 case ActiveTemplateInstantiation::ExceptionSpecInstantiation:
595 Diags.Report(Active->PointOfInstantiation,
596 diag::note_template_exception_spec_instantiation_here)
597 << cast<FunctionDecl>(Active->Entity)
598 << Active->InstantiationRange;
604 Optional<TemplateDeductionInfo *> Sema::isSFINAEContext() const {
605 if (InNonInstantiationSFINAEContext)
606 return Optional<TemplateDeductionInfo *>(nullptr);
608 for (SmallVectorImpl<ActiveTemplateInstantiation>::const_reverse_iterator
609 Active = ActiveTemplateInstantiations.rbegin(),
610 ActiveEnd = ActiveTemplateInstantiations.rend();
614 switch(Active->Kind) {
615 case ActiveTemplateInstantiation::TemplateInstantiation:
616 // An instantiation of an alias template may or may not be a SFINAE
617 // context, depending on what else is on the stack.
618 if (isa<TypeAliasTemplateDecl>(Active->Entity))
621 case ActiveTemplateInstantiation::DefaultFunctionArgumentInstantiation:
622 case ActiveTemplateInstantiation::ExceptionSpecInstantiation:
623 // This is a template instantiation, so there is no SFINAE.
626 case ActiveTemplateInstantiation::DefaultTemplateArgumentInstantiation:
627 case ActiveTemplateInstantiation::PriorTemplateArgumentSubstitution:
628 case ActiveTemplateInstantiation::DefaultTemplateArgumentChecking:
629 // A default template argument instantiation and substitution into
630 // template parameters with arguments for prior parameters may or may
631 // not be a SFINAE context; look further up the stack.
634 case ActiveTemplateInstantiation::ExplicitTemplateArgumentSubstitution:
635 case ActiveTemplateInstantiation::DeducedTemplateArgumentSubstitution:
636 // We're either substitution explicitly-specified template arguments
637 // or deduced template arguments, so SFINAE applies.
638 assert(Active->DeductionInfo && "Missing deduction info pointer");
639 return Active->DeductionInfo;
646 /// \brief Retrieve the depth and index of a parameter pack.
647 static std::pair<unsigned, unsigned>
648 getDepthAndIndex(NamedDecl *ND) {
649 if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(ND))
650 return std::make_pair(TTP->getDepth(), TTP->getIndex());
652 if (NonTypeTemplateParmDecl *NTTP = dyn_cast<NonTypeTemplateParmDecl>(ND))
653 return std::make_pair(NTTP->getDepth(), NTTP->getIndex());
655 TemplateTemplateParmDecl *TTP = cast<TemplateTemplateParmDecl>(ND);
656 return std::make_pair(TTP->getDepth(), TTP->getIndex());
659 //===----------------------------------------------------------------------===/
660 // Template Instantiation for Types
661 //===----------------------------------------------------------------------===/
663 class TemplateInstantiator : public TreeTransform<TemplateInstantiator> {
664 const MultiLevelTemplateArgumentList &TemplateArgs;
666 DeclarationName Entity;
669 typedef TreeTransform<TemplateInstantiator> inherited;
671 TemplateInstantiator(Sema &SemaRef,
672 const MultiLevelTemplateArgumentList &TemplateArgs,
674 DeclarationName Entity)
675 : inherited(SemaRef), TemplateArgs(TemplateArgs), Loc(Loc),
678 /// \brief Determine whether the given type \p T has already been
681 /// For the purposes of template instantiation, a type has already been
682 /// transformed if it is NULL or if it is not dependent.
683 bool AlreadyTransformed(QualType T);
685 /// \brief Returns the location of the entity being instantiated, if known.
686 SourceLocation getBaseLocation() { return Loc; }
688 /// \brief Returns the name of the entity being instantiated, if any.
689 DeclarationName getBaseEntity() { return Entity; }
691 /// \brief Sets the "base" location and entity when that
692 /// information is known based on another transformation.
693 void setBase(SourceLocation Loc, DeclarationName Entity) {
695 this->Entity = Entity;
698 bool TryExpandParameterPacks(SourceLocation EllipsisLoc,
699 SourceRange PatternRange,
700 ArrayRef<UnexpandedParameterPack> Unexpanded,
701 bool &ShouldExpand, bool &RetainExpansion,
702 Optional<unsigned> &NumExpansions) {
703 return getSema().CheckParameterPacksForExpansion(EllipsisLoc,
704 PatternRange, Unexpanded,
711 void ExpandingFunctionParameterPack(ParmVarDecl *Pack) {
712 SemaRef.CurrentInstantiationScope->MakeInstantiatedLocalArgPack(Pack);
715 TemplateArgument ForgetPartiallySubstitutedPack() {
716 TemplateArgument Result;
717 if (NamedDecl *PartialPack
718 = SemaRef.CurrentInstantiationScope->getPartiallySubstitutedPack()){
719 MultiLevelTemplateArgumentList &TemplateArgs
720 = const_cast<MultiLevelTemplateArgumentList &>(this->TemplateArgs);
721 unsigned Depth, Index;
722 std::tie(Depth, Index) = getDepthAndIndex(PartialPack);
723 if (TemplateArgs.hasTemplateArgument(Depth, Index)) {
724 Result = TemplateArgs(Depth, Index);
725 TemplateArgs.setArgument(Depth, Index, TemplateArgument());
732 void RememberPartiallySubstitutedPack(TemplateArgument Arg) {
736 if (NamedDecl *PartialPack
737 = SemaRef.CurrentInstantiationScope->getPartiallySubstitutedPack()){
738 MultiLevelTemplateArgumentList &TemplateArgs
739 = const_cast<MultiLevelTemplateArgumentList &>(this->TemplateArgs);
740 unsigned Depth, Index;
741 std::tie(Depth, Index) = getDepthAndIndex(PartialPack);
742 TemplateArgs.setArgument(Depth, Index, Arg);
746 /// \brief Transform the given declaration by instantiating a reference to
747 /// this declaration.
748 Decl *TransformDecl(SourceLocation Loc, Decl *D);
750 void transformAttrs(Decl *Old, Decl *New) {
751 SemaRef.InstantiateAttrs(TemplateArgs, Old, New);
754 void transformedLocalDecl(Decl *Old, Decl *New) {
755 // If we've instantiated the call operator of a lambda or the call
756 // operator template of a generic lambda, update the "instantiation of"
758 auto *NewMD = dyn_cast<CXXMethodDecl>(New);
759 if (NewMD && isLambdaCallOperator(NewMD)) {
760 auto *OldMD = dyn_cast<CXXMethodDecl>(Old);
761 if (auto *NewTD = NewMD->getDescribedFunctionTemplate())
762 NewTD->setInstantiatedFromMemberTemplate(
763 OldMD->getDescribedFunctionTemplate());
765 NewMD->setInstantiationOfMemberFunction(OldMD,
766 TSK_ImplicitInstantiation);
769 SemaRef.CurrentInstantiationScope->InstantiatedLocal(Old, New);
771 // We recreated a local declaration, but not by instantiating it. There
772 // may be pending dependent diagnostics to produce.
773 if (auto *DC = dyn_cast<DeclContext>(Old))
774 SemaRef.PerformDependentDiagnostics(DC, TemplateArgs);
777 /// \brief Transform the definition of the given declaration by
778 /// instantiating it.
779 Decl *TransformDefinition(SourceLocation Loc, Decl *D);
781 /// \brief Transform the first qualifier within a scope by instantiating the
783 NamedDecl *TransformFirstQualifierInScope(NamedDecl *D, SourceLocation Loc);
785 /// \brief Rebuild the exception declaration and register the declaration
786 /// as an instantiated local.
787 VarDecl *RebuildExceptionDecl(VarDecl *ExceptionDecl,
788 TypeSourceInfo *Declarator,
789 SourceLocation StartLoc,
790 SourceLocation NameLoc,
791 IdentifierInfo *Name);
793 /// \brief Rebuild the Objective-C exception declaration and register the
794 /// declaration as an instantiated local.
795 VarDecl *RebuildObjCExceptionDecl(VarDecl *ExceptionDecl,
796 TypeSourceInfo *TSInfo, QualType T);
798 /// \brief Check for tag mismatches when instantiating an
800 QualType RebuildElaboratedType(SourceLocation KeywordLoc,
801 ElaboratedTypeKeyword Keyword,
802 NestedNameSpecifierLoc QualifierLoc,
806 TransformTemplateName(CXXScopeSpec &SS, TemplateName Name,
807 SourceLocation NameLoc,
808 QualType ObjectType = QualType(),
809 NamedDecl *FirstQualifierInScope = nullptr);
811 const LoopHintAttr *TransformLoopHintAttr(const LoopHintAttr *LH);
813 ExprResult TransformPredefinedExpr(PredefinedExpr *E);
814 ExprResult TransformDeclRefExpr(DeclRefExpr *E);
815 ExprResult TransformCXXDefaultArgExpr(CXXDefaultArgExpr *E);
817 ExprResult TransformTemplateParmRefExpr(DeclRefExpr *E,
818 NonTypeTemplateParmDecl *D);
819 ExprResult TransformSubstNonTypeTemplateParmPackExpr(
820 SubstNonTypeTemplateParmPackExpr *E);
822 /// \brief Rebuild a DeclRefExpr for a ParmVarDecl reference.
823 ExprResult RebuildParmVarDeclRefExpr(ParmVarDecl *PD, SourceLocation Loc);
825 /// \brief Transform a reference to a function parameter pack.
826 ExprResult TransformFunctionParmPackRefExpr(DeclRefExpr *E,
829 /// \brief Transform a FunctionParmPackExpr which was built when we couldn't
830 /// expand a function parameter pack reference which refers to an expanded
832 ExprResult TransformFunctionParmPackExpr(FunctionParmPackExpr *E);
834 QualType TransformFunctionProtoType(TypeLocBuilder &TLB,
835 FunctionProtoTypeLoc TL) {
836 // Call the base version; it will forward to our overridden version below.
837 return inherited::TransformFunctionProtoType(TLB, TL);
840 template<typename Fn>
841 QualType TransformFunctionProtoType(TypeLocBuilder &TLB,
842 FunctionProtoTypeLoc TL,
843 CXXRecordDecl *ThisContext,
844 unsigned ThisTypeQuals,
845 Fn TransformExceptionSpec);
847 ParmVarDecl *TransformFunctionTypeParam(ParmVarDecl *OldParm,
849 Optional<unsigned> NumExpansions,
850 bool ExpectParameterPack);
852 /// \brief Transforms a template type parameter type by performing
853 /// substitution of the corresponding template type argument.
854 QualType TransformTemplateTypeParmType(TypeLocBuilder &TLB,
855 TemplateTypeParmTypeLoc TL);
857 /// \brief Transforms an already-substituted template type parameter pack
858 /// into either itself (if we aren't substituting into its pack expansion)
859 /// or the appropriate substituted argument.
860 QualType TransformSubstTemplateTypeParmPackType(TypeLocBuilder &TLB,
861 SubstTemplateTypeParmPackTypeLoc TL);
863 ExprResult TransformLambdaExpr(LambdaExpr *E) {
864 LocalInstantiationScope Scope(SemaRef, /*CombineWithOuterScope=*/true);
865 return TreeTransform<TemplateInstantiator>::TransformLambdaExpr(E);
868 TemplateParameterList *TransformTemplateParameterList(
869 TemplateParameterList *OrigTPL) {
870 if (!OrigTPL || !OrigTPL->size()) return OrigTPL;
872 DeclContext *Owner = OrigTPL->getParam(0)->getDeclContext();
873 TemplateDeclInstantiator DeclInstantiator(getSema(),
874 /* DeclContext *Owner */ Owner, TemplateArgs);
875 return DeclInstantiator.SubstTemplateParams(OrigTPL);
878 ExprResult transformNonTypeTemplateParmRef(NonTypeTemplateParmDecl *parm,
880 TemplateArgument arg);
884 bool TemplateInstantiator::AlreadyTransformed(QualType T) {
888 if (T->isInstantiationDependentType() || T->isVariablyModifiedType())
891 getSema().MarkDeclarationsReferencedInType(Loc, T);
895 static TemplateArgument
896 getPackSubstitutedTemplateArgument(Sema &S, TemplateArgument Arg) {
897 assert(S.ArgumentPackSubstitutionIndex >= 0);
898 assert(S.ArgumentPackSubstitutionIndex < (int)Arg.pack_size());
899 Arg = Arg.pack_begin()[S.ArgumentPackSubstitutionIndex];
900 if (Arg.isPackExpansion())
901 Arg = Arg.getPackExpansionPattern();
905 Decl *TemplateInstantiator::TransformDecl(SourceLocation Loc, Decl *D) {
909 if (TemplateTemplateParmDecl *TTP = dyn_cast<TemplateTemplateParmDecl>(D)) {
910 if (TTP->getDepth() < TemplateArgs.getNumLevels()) {
911 // If the corresponding template argument is NULL or non-existent, it's
912 // because we are performing instantiation from explicitly-specified
913 // template arguments in a function template, but there were some
914 // arguments left unspecified.
915 if (!TemplateArgs.hasTemplateArgument(TTP->getDepth(),
919 TemplateArgument Arg = TemplateArgs(TTP->getDepth(), TTP->getPosition());
921 if (TTP->isParameterPack()) {
922 assert(Arg.getKind() == TemplateArgument::Pack &&
923 "Missing argument pack");
924 Arg = getPackSubstitutedTemplateArgument(getSema(), Arg);
927 TemplateName Template = Arg.getAsTemplate();
928 assert(!Template.isNull() && Template.getAsTemplateDecl() &&
929 "Wrong kind of template template argument");
930 return Template.getAsTemplateDecl();
933 // Fall through to find the instantiated declaration for this template
934 // template parameter.
937 return SemaRef.FindInstantiatedDecl(Loc, cast<NamedDecl>(D), TemplateArgs);
940 Decl *TemplateInstantiator::TransformDefinition(SourceLocation Loc, Decl *D) {
941 Decl *Inst = getSema().SubstDecl(D, getSema().CurContext, TemplateArgs);
945 getSema().CurrentInstantiationScope->InstantiatedLocal(D, Inst);
950 TemplateInstantiator::TransformFirstQualifierInScope(NamedDecl *D,
951 SourceLocation Loc) {
952 // If the first part of the nested-name-specifier was a template type
953 // parameter, instantiate that type parameter down to a tag type.
954 if (TemplateTypeParmDecl *TTPD = dyn_cast_or_null<TemplateTypeParmDecl>(D)) {
955 const TemplateTypeParmType *TTP
956 = cast<TemplateTypeParmType>(getSema().Context.getTypeDeclType(TTPD));
958 if (TTP->getDepth() < TemplateArgs.getNumLevels()) {
959 // FIXME: This needs testing w/ member access expressions.
960 TemplateArgument Arg = TemplateArgs(TTP->getDepth(), TTP->getIndex());
962 if (TTP->isParameterPack()) {
963 assert(Arg.getKind() == TemplateArgument::Pack &&
964 "Missing argument pack");
966 if (getSema().ArgumentPackSubstitutionIndex == -1)
969 Arg = getPackSubstitutedTemplateArgument(getSema(), Arg);
972 QualType T = Arg.getAsType();
974 return cast_or_null<NamedDecl>(TransformDecl(Loc, D));
976 if (const TagType *Tag = T->getAs<TagType>())
977 return Tag->getDecl();
979 // The resulting type is not a tag; complain.
980 getSema().Diag(Loc, diag::err_nested_name_spec_non_tag) << T;
985 return cast_or_null<NamedDecl>(TransformDecl(Loc, D));
989 TemplateInstantiator::RebuildExceptionDecl(VarDecl *ExceptionDecl,
990 TypeSourceInfo *Declarator,
991 SourceLocation StartLoc,
992 SourceLocation NameLoc,
993 IdentifierInfo *Name) {
994 VarDecl *Var = inherited::RebuildExceptionDecl(ExceptionDecl, Declarator,
995 StartLoc, NameLoc, Name);
997 getSema().CurrentInstantiationScope->InstantiatedLocal(ExceptionDecl, Var);
1001 VarDecl *TemplateInstantiator::RebuildObjCExceptionDecl(VarDecl *ExceptionDecl,
1002 TypeSourceInfo *TSInfo,
1004 VarDecl *Var = inherited::RebuildObjCExceptionDecl(ExceptionDecl, TSInfo, T);
1006 getSema().CurrentInstantiationScope->InstantiatedLocal(ExceptionDecl, Var);
1011 TemplateInstantiator::RebuildElaboratedType(SourceLocation KeywordLoc,
1012 ElaboratedTypeKeyword Keyword,
1013 NestedNameSpecifierLoc QualifierLoc,
1015 if (const TagType *TT = T->getAs<TagType>()) {
1016 TagDecl* TD = TT->getDecl();
1018 SourceLocation TagLocation = KeywordLoc;
1020 IdentifierInfo *Id = TD->getIdentifier();
1022 // TODO: should we even warn on struct/class mismatches for this? Seems
1023 // like it's likely to produce a lot of spurious errors.
1024 if (Id && Keyword != ETK_None && Keyword != ETK_Typename) {
1025 TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForKeyword(Keyword);
1026 if (!SemaRef.isAcceptableTagRedeclaration(TD, Kind, /*isDefinition*/false,
1028 SemaRef.Diag(TagLocation, diag::err_use_with_wrong_tag)
1030 << FixItHint::CreateReplacement(SourceRange(TagLocation),
1032 SemaRef.Diag(TD->getLocation(), diag::note_previous_use);
1037 return TreeTransform<TemplateInstantiator>::RebuildElaboratedType(KeywordLoc,
1043 TemplateName TemplateInstantiator::TransformTemplateName(CXXScopeSpec &SS,
1045 SourceLocation NameLoc,
1046 QualType ObjectType,
1047 NamedDecl *FirstQualifierInScope) {
1048 if (TemplateTemplateParmDecl *TTP
1049 = dyn_cast_or_null<TemplateTemplateParmDecl>(Name.getAsTemplateDecl())) {
1050 if (TTP->getDepth() < TemplateArgs.getNumLevels()) {
1051 // If the corresponding template argument is NULL or non-existent, it's
1052 // because we are performing instantiation from explicitly-specified
1053 // template arguments in a function template, but there were some
1054 // arguments left unspecified.
1055 if (!TemplateArgs.hasTemplateArgument(TTP->getDepth(),
1056 TTP->getPosition()))
1059 TemplateArgument Arg = TemplateArgs(TTP->getDepth(), TTP->getPosition());
1061 if (TTP->isParameterPack()) {
1062 assert(Arg.getKind() == TemplateArgument::Pack &&
1063 "Missing argument pack");
1065 if (getSema().ArgumentPackSubstitutionIndex == -1) {
1066 // We have the template argument pack to substitute, but we're not
1067 // actually expanding the enclosing pack expansion yet. So, just
1068 // keep the entire argument pack.
1069 return getSema().Context.getSubstTemplateTemplateParmPack(TTP, Arg);
1072 Arg = getPackSubstitutedTemplateArgument(getSema(), Arg);
1075 TemplateName Template = Arg.getAsTemplate();
1076 assert(!Template.isNull() && "Null template template argument");
1078 // We don't ever want to substitute for a qualified template name, since
1079 // the qualifier is handled separately. So, look through the qualified
1080 // template name to its underlying declaration.
1081 if (QualifiedTemplateName *QTN = Template.getAsQualifiedTemplateName())
1082 Template = TemplateName(QTN->getTemplateDecl());
1084 Template = getSema().Context.getSubstTemplateTemplateParm(TTP, Template);
1089 if (SubstTemplateTemplateParmPackStorage *SubstPack
1090 = Name.getAsSubstTemplateTemplateParmPack()) {
1091 if (getSema().ArgumentPackSubstitutionIndex == -1)
1094 TemplateArgument Arg = SubstPack->getArgumentPack();
1095 Arg = getPackSubstitutedTemplateArgument(getSema(), Arg);
1096 return Arg.getAsTemplate();
1099 return inherited::TransformTemplateName(SS, Name, NameLoc, ObjectType,
1100 FirstQualifierInScope);
1104 TemplateInstantiator::TransformPredefinedExpr(PredefinedExpr *E) {
1105 if (!E->isTypeDependent())
1108 return getSema().BuildPredefinedExpr(E->getLocation(), E->getIdentType());
1112 TemplateInstantiator::TransformTemplateParmRefExpr(DeclRefExpr *E,
1113 NonTypeTemplateParmDecl *NTTP) {
1114 // If the corresponding template argument is NULL or non-existent, it's
1115 // because we are performing instantiation from explicitly-specified
1116 // template arguments in a function template, but there were some
1117 // arguments left unspecified.
1118 if (!TemplateArgs.hasTemplateArgument(NTTP->getDepth(),
1119 NTTP->getPosition()))
1122 TemplateArgument Arg = TemplateArgs(NTTP->getDepth(), NTTP->getPosition());
1123 if (NTTP->isParameterPack()) {
1124 assert(Arg.getKind() == TemplateArgument::Pack &&
1125 "Missing argument pack");
1127 if (getSema().ArgumentPackSubstitutionIndex == -1) {
1128 // We have an argument pack, but we can't select a particular argument
1129 // out of it yet. Therefore, we'll build an expression to hold on to that
1131 QualType TargetType = SemaRef.SubstType(NTTP->getType(), TemplateArgs,
1133 NTTP->getDeclName());
1134 if (TargetType.isNull())
1137 return new (SemaRef.Context) SubstNonTypeTemplateParmPackExpr(TargetType,
1143 Arg = getPackSubstitutedTemplateArgument(getSema(), Arg);
1146 return transformNonTypeTemplateParmRef(NTTP, E->getLocation(), Arg);
1149 const LoopHintAttr *
1150 TemplateInstantiator::TransformLoopHintAttr(const LoopHintAttr *LH) {
1151 Expr *TransformedExpr = getDerived().TransformExpr(LH->getValue()).get();
1153 if (TransformedExpr == LH->getValue())
1156 // Generate error if there is a problem with the value.
1157 if (getSema().CheckLoopHintExpr(TransformedExpr, LH->getLocation()))
1160 // Create new LoopHintValueAttr with integral expression in place of the
1161 // non-type template parameter.
1162 return LoopHintAttr::CreateImplicit(
1163 getSema().Context, LH->getSemanticSpelling(), LH->getOption(),
1164 LH->getState(), TransformedExpr, LH->getRange());
1167 ExprResult TemplateInstantiator::transformNonTypeTemplateParmRef(
1168 NonTypeTemplateParmDecl *parm,
1170 TemplateArgument arg) {
1174 // The template argument itself might be an expression, in which
1175 // case we just return that expression.
1176 if (arg.getKind() == TemplateArgument::Expression) {
1177 Expr *argExpr = arg.getAsExpr();
1179 type = argExpr->getType();
1181 } else if (arg.getKind() == TemplateArgument::Declaration ||
1182 arg.getKind() == TemplateArgument::NullPtr) {
1184 if (arg.getKind() == TemplateArgument::Declaration) {
1185 VD = cast<ValueDecl>(arg.getAsDecl());
1187 // Find the instantiation of the template argument. This is
1188 // required for nested templates.
1189 VD = cast_or_null<ValueDecl>(
1190 getSema().FindInstantiatedDecl(loc, VD, TemplateArgs));
1194 // Propagate NULL template argument.
1198 // Derive the type we want the substituted decl to have. This had
1199 // better be non-dependent, or these checks will have serious problems.
1200 if (parm->isExpandedParameterPack()) {
1201 type = parm->getExpansionType(SemaRef.ArgumentPackSubstitutionIndex);
1202 } else if (parm->isParameterPack() &&
1203 isa<PackExpansionType>(parm->getType())) {
1204 type = SemaRef.SubstType(
1205 cast<PackExpansionType>(parm->getType())->getPattern(),
1206 TemplateArgs, loc, parm->getDeclName());
1208 type = SemaRef.SubstType(VD ? arg.getParamTypeForDecl() : arg.getNullPtrType(),
1209 TemplateArgs, loc, parm->getDeclName());
1211 assert(!type.isNull() && "type substitution failed for param type");
1212 assert(!type->isDependentType() && "param type still dependent");
1213 result = SemaRef.BuildExpressionFromDeclTemplateArgument(arg, type, loc);
1215 if (!result.isInvalid()) type = result.get()->getType();
1217 result = SemaRef.BuildExpressionFromIntegralTemplateArgument(arg, loc);
1219 // Note that this type can be different from the type of 'result',
1220 // e.g. if it's an enum type.
1221 type = arg.getIntegralType();
1223 if (result.isInvalid()) return ExprError();
1225 Expr *resultExpr = result.get();
1226 return new (SemaRef.Context) SubstNonTypeTemplateParmExpr(
1227 type, resultExpr->getValueKind(), loc, parm, resultExpr);
1231 TemplateInstantiator::TransformSubstNonTypeTemplateParmPackExpr(
1232 SubstNonTypeTemplateParmPackExpr *E) {
1233 if (getSema().ArgumentPackSubstitutionIndex == -1) {
1234 // We aren't expanding the parameter pack, so just return ourselves.
1238 TemplateArgument Arg = E->getArgumentPack();
1239 Arg = getPackSubstitutedTemplateArgument(getSema(), Arg);
1240 return transformNonTypeTemplateParmRef(E->getParameterPack(),
1241 E->getParameterPackLocation(),
1246 TemplateInstantiator::RebuildParmVarDeclRefExpr(ParmVarDecl *PD,
1247 SourceLocation Loc) {
1248 DeclarationNameInfo NameInfo(PD->getDeclName(), Loc);
1249 return getSema().BuildDeclarationNameExpr(CXXScopeSpec(), NameInfo, PD);
1253 TemplateInstantiator::TransformFunctionParmPackExpr(FunctionParmPackExpr *E) {
1254 if (getSema().ArgumentPackSubstitutionIndex != -1) {
1255 // We can expand this parameter pack now.
1256 ParmVarDecl *D = E->getExpansion(getSema().ArgumentPackSubstitutionIndex);
1257 ValueDecl *VD = cast_or_null<ValueDecl>(TransformDecl(E->getExprLoc(), D));
1260 return RebuildParmVarDeclRefExpr(cast<ParmVarDecl>(VD), E->getExprLoc());
1263 QualType T = TransformType(E->getType());
1267 // Transform each of the parameter expansions into the corresponding
1268 // parameters in the instantiation of the function decl.
1269 SmallVector<ParmVarDecl *, 8> Parms;
1270 Parms.reserve(E->getNumExpansions());
1271 for (FunctionParmPackExpr::iterator I = E->begin(), End = E->end();
1274 cast_or_null<ParmVarDecl>(TransformDecl(E->getExprLoc(), *I));
1280 return FunctionParmPackExpr::Create(getSema().Context, T,
1281 E->getParameterPack(),
1282 E->getParameterPackLocation(), Parms);
1286 TemplateInstantiator::TransformFunctionParmPackRefExpr(DeclRefExpr *E,
1288 typedef LocalInstantiationScope::DeclArgumentPack DeclArgumentPack;
1289 llvm::PointerUnion<Decl *, DeclArgumentPack *> *Found
1290 = getSema().CurrentInstantiationScope->findInstantiationOf(PD);
1291 assert(Found && "no instantiation for parameter pack");
1293 Decl *TransformedDecl;
1294 if (DeclArgumentPack *Pack = Found->dyn_cast<DeclArgumentPack *>()) {
1295 // If this is a reference to a function parameter pack which we can
1296 // substitute but can't yet expand, build a FunctionParmPackExpr for it.
1297 if (getSema().ArgumentPackSubstitutionIndex == -1) {
1298 QualType T = TransformType(E->getType());
1301 return FunctionParmPackExpr::Create(getSema().Context, T, PD,
1302 E->getExprLoc(), *Pack);
1305 TransformedDecl = (*Pack)[getSema().ArgumentPackSubstitutionIndex];
1307 TransformedDecl = Found->get<Decl*>();
1310 // We have either an unexpanded pack or a specific expansion.
1311 return RebuildParmVarDeclRefExpr(cast<ParmVarDecl>(TransformedDecl),
1316 TemplateInstantiator::TransformDeclRefExpr(DeclRefExpr *E) {
1317 NamedDecl *D = E->getDecl();
1319 // Handle references to non-type template parameters and non-type template
1321 if (NonTypeTemplateParmDecl *NTTP = dyn_cast<NonTypeTemplateParmDecl>(D)) {
1322 if (NTTP->getDepth() < TemplateArgs.getNumLevels())
1323 return TransformTemplateParmRefExpr(E, NTTP);
1325 // We have a non-type template parameter that isn't fully substituted;
1326 // FindInstantiatedDecl will find it in the local instantiation scope.
1329 // Handle references to function parameter packs.
1330 if (ParmVarDecl *PD = dyn_cast<ParmVarDecl>(D))
1331 if (PD->isParameterPack())
1332 return TransformFunctionParmPackRefExpr(E, PD);
1334 return TreeTransform<TemplateInstantiator>::TransformDeclRefExpr(E);
1337 ExprResult TemplateInstantiator::TransformCXXDefaultArgExpr(
1338 CXXDefaultArgExpr *E) {
1339 assert(!cast<FunctionDecl>(E->getParam()->getDeclContext())->
1340 getDescribedFunctionTemplate() &&
1341 "Default arg expressions are never formed in dependent cases.");
1342 return SemaRef.BuildCXXDefaultArgExpr(E->getUsedLocation(),
1343 cast<FunctionDecl>(E->getParam()->getDeclContext()),
1347 template<typename Fn>
1348 QualType TemplateInstantiator::TransformFunctionProtoType(TypeLocBuilder &TLB,
1349 FunctionProtoTypeLoc TL,
1350 CXXRecordDecl *ThisContext,
1351 unsigned ThisTypeQuals,
1352 Fn TransformExceptionSpec) {
1353 // We need a local instantiation scope for this function prototype.
1354 LocalInstantiationScope Scope(SemaRef, /*CombineWithOuterScope=*/true);
1355 return inherited::TransformFunctionProtoType(
1356 TLB, TL, ThisContext, ThisTypeQuals, TransformExceptionSpec);
1360 TemplateInstantiator::TransformFunctionTypeParam(ParmVarDecl *OldParm,
1361 int indexAdjustment,
1362 Optional<unsigned> NumExpansions,
1363 bool ExpectParameterPack) {
1364 return SemaRef.SubstParmVarDecl(OldParm, TemplateArgs, indexAdjustment,
1365 NumExpansions, ExpectParameterPack);
1369 TemplateInstantiator::TransformTemplateTypeParmType(TypeLocBuilder &TLB,
1370 TemplateTypeParmTypeLoc TL) {
1371 const TemplateTypeParmType *T = TL.getTypePtr();
1372 if (T->getDepth() < TemplateArgs.getNumLevels()) {
1373 // Replace the template type parameter with its corresponding
1374 // template argument.
1376 // If the corresponding template argument is NULL or doesn't exist, it's
1377 // because we are performing instantiation from explicitly-specified
1378 // template arguments in a function template class, but there were some
1379 // arguments left unspecified.
1380 if (!TemplateArgs.hasTemplateArgument(T->getDepth(), T->getIndex())) {
1381 TemplateTypeParmTypeLoc NewTL
1382 = TLB.push<TemplateTypeParmTypeLoc>(TL.getType());
1383 NewTL.setNameLoc(TL.getNameLoc());
1384 return TL.getType();
1387 TemplateArgument Arg = TemplateArgs(T->getDepth(), T->getIndex());
1389 if (T->isParameterPack()) {
1390 assert(Arg.getKind() == TemplateArgument::Pack &&
1391 "Missing argument pack");
1393 if (getSema().ArgumentPackSubstitutionIndex == -1) {
1394 // We have the template argument pack, but we're not expanding the
1395 // enclosing pack expansion yet. Just save the template argument
1396 // pack for later substitution.
1398 = getSema().Context.getSubstTemplateTypeParmPackType(T, Arg);
1399 SubstTemplateTypeParmPackTypeLoc NewTL
1400 = TLB.push<SubstTemplateTypeParmPackTypeLoc>(Result);
1401 NewTL.setNameLoc(TL.getNameLoc());
1405 Arg = getPackSubstitutedTemplateArgument(getSema(), Arg);
1408 assert(Arg.getKind() == TemplateArgument::Type &&
1409 "Template argument kind mismatch");
1411 QualType Replacement = Arg.getAsType();
1413 // TODO: only do this uniquing once, at the start of instantiation.
1415 = getSema().Context.getSubstTemplateTypeParmType(T, Replacement);
1416 SubstTemplateTypeParmTypeLoc NewTL
1417 = TLB.push<SubstTemplateTypeParmTypeLoc>(Result);
1418 NewTL.setNameLoc(TL.getNameLoc());
1422 // The template type parameter comes from an inner template (e.g.,
1423 // the template parameter list of a member template inside the
1424 // template we are instantiating). Create a new template type
1425 // parameter with the template "level" reduced by one.
1426 TemplateTypeParmDecl *NewTTPDecl = nullptr;
1427 if (TemplateTypeParmDecl *OldTTPDecl = T->getDecl())
1428 NewTTPDecl = cast_or_null<TemplateTypeParmDecl>(
1429 TransformDecl(TL.getNameLoc(), OldTTPDecl));
1432 = getSema().Context.getTemplateTypeParmType(T->getDepth()
1433 - TemplateArgs.getNumLevels(),
1435 T->isParameterPack(),
1437 TemplateTypeParmTypeLoc NewTL = TLB.push<TemplateTypeParmTypeLoc>(Result);
1438 NewTL.setNameLoc(TL.getNameLoc());
1443 TemplateInstantiator::TransformSubstTemplateTypeParmPackType(
1444 TypeLocBuilder &TLB,
1445 SubstTemplateTypeParmPackTypeLoc TL) {
1446 if (getSema().ArgumentPackSubstitutionIndex == -1) {
1447 // We aren't expanding the parameter pack, so just return ourselves.
1448 SubstTemplateTypeParmPackTypeLoc NewTL
1449 = TLB.push<SubstTemplateTypeParmPackTypeLoc>(TL.getType());
1450 NewTL.setNameLoc(TL.getNameLoc());
1451 return TL.getType();
1454 TemplateArgument Arg = TL.getTypePtr()->getArgumentPack();
1455 Arg = getPackSubstitutedTemplateArgument(getSema(), Arg);
1456 QualType Result = Arg.getAsType();
1458 Result = getSema().Context.getSubstTemplateTypeParmType(
1459 TL.getTypePtr()->getReplacedParameter(),
1461 SubstTemplateTypeParmTypeLoc NewTL
1462 = TLB.push<SubstTemplateTypeParmTypeLoc>(Result);
1463 NewTL.setNameLoc(TL.getNameLoc());
1467 /// \brief Perform substitution on the type T with a given set of template
1470 /// This routine substitutes the given template arguments into the
1471 /// type T and produces the instantiated type.
1473 /// \param T the type into which the template arguments will be
1474 /// substituted. If this type is not dependent, it will be returned
1477 /// \param Args the template arguments that will be
1478 /// substituted for the top-level template parameters within T.
1480 /// \param Loc the location in the source code where this substitution
1481 /// is being performed. It will typically be the location of the
1482 /// declarator (if we're instantiating the type of some declaration)
1483 /// or the location of the type in the source code (if, e.g., we're
1484 /// instantiating the type of a cast expression).
1486 /// \param Entity the name of the entity associated with a declaration
1487 /// being instantiated (if any). May be empty to indicate that there
1488 /// is no such entity (if, e.g., this is a type that occurs as part of
1489 /// a cast expression) or that the entity has no name (e.g., an
1490 /// unnamed function parameter).
1492 /// \returns If the instantiation succeeds, the instantiated
1493 /// type. Otherwise, produces diagnostics and returns a NULL type.
1494 TypeSourceInfo *Sema::SubstType(TypeSourceInfo *T,
1495 const MultiLevelTemplateArgumentList &Args,
1497 DeclarationName Entity) {
1498 assert(!ActiveTemplateInstantiations.empty() &&
1499 "Cannot perform an instantiation without some context on the "
1500 "instantiation stack");
1502 if (!T->getType()->isInstantiationDependentType() &&
1503 !T->getType()->isVariablyModifiedType())
1506 TemplateInstantiator Instantiator(*this, Args, Loc, Entity);
1507 return Instantiator.TransformType(T);
1510 TypeSourceInfo *Sema::SubstType(TypeLoc TL,
1511 const MultiLevelTemplateArgumentList &Args,
1513 DeclarationName Entity) {
1514 assert(!ActiveTemplateInstantiations.empty() &&
1515 "Cannot perform an instantiation without some context on the "
1516 "instantiation stack");
1518 if (TL.getType().isNull())
1521 if (!TL.getType()->isInstantiationDependentType() &&
1522 !TL.getType()->isVariablyModifiedType()) {
1523 // FIXME: Make a copy of the TypeLoc data here, so that we can
1524 // return a new TypeSourceInfo. Inefficient!
1526 TLB.pushFullCopy(TL);
1527 return TLB.getTypeSourceInfo(Context, TL.getType());
1530 TemplateInstantiator Instantiator(*this, Args, Loc, Entity);
1532 TLB.reserve(TL.getFullDataSize());
1533 QualType Result = Instantiator.TransformType(TLB, TL);
1534 if (Result.isNull())
1537 return TLB.getTypeSourceInfo(Context, Result);
1540 /// Deprecated form of the above.
1541 QualType Sema::SubstType(QualType T,
1542 const MultiLevelTemplateArgumentList &TemplateArgs,
1543 SourceLocation Loc, DeclarationName Entity) {
1544 assert(!ActiveTemplateInstantiations.empty() &&
1545 "Cannot perform an instantiation without some context on the "
1546 "instantiation stack");
1548 // If T is not a dependent type or a variably-modified type, there
1549 // is nothing to do.
1550 if (!T->isInstantiationDependentType() && !T->isVariablyModifiedType())
1553 TemplateInstantiator Instantiator(*this, TemplateArgs, Loc, Entity);
1554 return Instantiator.TransformType(T);
1557 static bool NeedsInstantiationAsFunctionType(TypeSourceInfo *T) {
1558 if (T->getType()->isInstantiationDependentType() ||
1559 T->getType()->isVariablyModifiedType())
1562 TypeLoc TL = T->getTypeLoc().IgnoreParens();
1563 if (!TL.getAs<FunctionProtoTypeLoc>())
1566 FunctionProtoTypeLoc FP = TL.castAs<FunctionProtoTypeLoc>();
1567 for (ParmVarDecl *P : FP.getParams()) {
1568 // This must be synthesized from a typedef.
1571 // If there are any parameters, a new TypeSourceInfo that refers to the
1572 // instantiated parameters must be built.
1579 /// A form of SubstType intended specifically for instantiating the
1580 /// type of a FunctionDecl. Its purpose is solely to force the
1581 /// instantiation of default-argument expressions and to avoid
1582 /// instantiating an exception-specification.
1583 TypeSourceInfo *Sema::SubstFunctionDeclType(TypeSourceInfo *T,
1584 const MultiLevelTemplateArgumentList &Args,
1586 DeclarationName Entity,
1587 CXXRecordDecl *ThisContext,
1588 unsigned ThisTypeQuals) {
1589 assert(!ActiveTemplateInstantiations.empty() &&
1590 "Cannot perform an instantiation without some context on the "
1591 "instantiation stack");
1593 if (!NeedsInstantiationAsFunctionType(T))
1596 TemplateInstantiator Instantiator(*this, Args, Loc, Entity);
1600 TypeLoc TL = T->getTypeLoc();
1601 TLB.reserve(TL.getFullDataSize());
1605 if (FunctionProtoTypeLoc Proto =
1606 TL.IgnoreParens().getAs<FunctionProtoTypeLoc>()) {
1607 // Instantiate the type, other than its exception specification. The
1608 // exception specification is instantiated in InitFunctionInstantiation
1609 // once we've built the FunctionDecl.
1610 // FIXME: Set the exception specification to EST_Uninstantiated here,
1611 // instead of rebuilding the function type again later.
1612 Result = Instantiator.TransformFunctionProtoType(
1613 TLB, Proto, ThisContext, ThisTypeQuals,
1614 [](FunctionProtoType::ExceptionSpecInfo &ESI,
1615 bool &Changed) { return false; });
1617 Result = Instantiator.TransformType(TLB, TL);
1619 if (Result.isNull())
1622 return TLB.getTypeSourceInfo(Context, Result);
1625 void Sema::SubstExceptionSpec(FunctionDecl *New, const FunctionProtoType *Proto,
1626 const MultiLevelTemplateArgumentList &Args) {
1627 FunctionProtoType::ExceptionSpecInfo ESI =
1628 Proto->getExtProtoInfo().ExceptionSpec;
1629 assert(ESI.Type != EST_Uninstantiated);
1631 TemplateInstantiator Instantiator(*this, Args, New->getLocation(),
1632 New->getDeclName());
1634 SmallVector<QualType, 4> ExceptionStorage;
1635 bool Changed = false;
1636 if (Instantiator.TransformExceptionSpec(
1637 New->getTypeSourceInfo()->getTypeLoc().getLocEnd(), ESI,
1638 ExceptionStorage, Changed))
1639 // On error, recover by dropping the exception specification.
1640 ESI.Type = EST_None;
1642 UpdateExceptionSpec(New, ESI);
1645 ParmVarDecl *Sema::SubstParmVarDecl(ParmVarDecl *OldParm,
1646 const MultiLevelTemplateArgumentList &TemplateArgs,
1647 int indexAdjustment,
1648 Optional<unsigned> NumExpansions,
1649 bool ExpectParameterPack) {
1650 TypeSourceInfo *OldDI = OldParm->getTypeSourceInfo();
1651 TypeSourceInfo *NewDI = nullptr;
1653 TypeLoc OldTL = OldDI->getTypeLoc();
1654 if (PackExpansionTypeLoc ExpansionTL = OldTL.getAs<PackExpansionTypeLoc>()) {
1656 // We have a function parameter pack. Substitute into the pattern of the
1658 NewDI = SubstType(ExpansionTL.getPatternLoc(), TemplateArgs,
1659 OldParm->getLocation(), OldParm->getDeclName());
1663 if (NewDI->getType()->containsUnexpandedParameterPack()) {
1664 // We still have unexpanded parameter packs, which means that
1665 // our function parameter is still a function parameter pack.
1666 // Therefore, make its type a pack expansion type.
1667 NewDI = CheckPackExpansion(NewDI, ExpansionTL.getEllipsisLoc(),
1669 } else if (ExpectParameterPack) {
1670 // We expected to get a parameter pack but didn't (because the type
1671 // itself is not a pack expansion type), so complain. This can occur when
1672 // the substitution goes through an alias template that "loses" the
1674 Diag(OldParm->getLocation(),
1675 diag::err_function_parameter_pack_without_parameter_packs)
1676 << NewDI->getType();
1680 NewDI = SubstType(OldDI, TemplateArgs, OldParm->getLocation(),
1681 OldParm->getDeclName());
1687 if (NewDI->getType()->isVoidType()) {
1688 Diag(OldParm->getLocation(), diag::err_param_with_void_type);
1692 ParmVarDecl *NewParm = CheckParameter(Context.getTranslationUnitDecl(),
1693 OldParm->getInnerLocStart(),
1694 OldParm->getLocation(),
1695 OldParm->getIdentifier(),
1696 NewDI->getType(), NewDI,
1697 OldParm->getStorageClass());
1701 // Mark the (new) default argument as uninstantiated (if any).
1702 if (OldParm->hasUninstantiatedDefaultArg()) {
1703 Expr *Arg = OldParm->getUninstantiatedDefaultArg();
1704 NewParm->setUninstantiatedDefaultArg(Arg);
1705 } else if (OldParm->hasUnparsedDefaultArg()) {
1706 NewParm->setUnparsedDefaultArg();
1707 UnparsedDefaultArgInstantiations[OldParm].push_back(NewParm);
1708 } else if (Expr *Arg = OldParm->getDefaultArg()) {
1709 FunctionDecl *OwningFunc = cast<FunctionDecl>(OldParm->getDeclContext());
1710 if (OwningFunc->isLexicallyWithinFunctionOrMethod()) {
1711 // Instantiate default arguments for methods of local classes (DR1484)
1712 // and non-defining declarations.
1713 Sema::ContextRAII SavedContext(*this, OwningFunc);
1714 LocalInstantiationScope Local(*this, true);
1715 ExprResult NewArg = SubstExpr(Arg, TemplateArgs);
1716 if (NewArg.isUsable()) {
1717 // It would be nice if we still had this.
1718 SourceLocation EqualLoc = NewArg.get()->getLocStart();
1719 SetParamDefaultArgument(NewParm, NewArg.get(), EqualLoc);
1722 // FIXME: if we non-lazily instantiated non-dependent default args for
1723 // non-dependent parameter types we could remove a bunch of duplicate
1724 // conversion warnings for such arguments.
1725 NewParm->setUninstantiatedDefaultArg(Arg);
1729 NewParm->setHasInheritedDefaultArg(OldParm->hasInheritedDefaultArg());
1731 if (OldParm->isParameterPack() && !NewParm->isParameterPack()) {
1732 // Add the new parameter to the instantiated parameter pack.
1733 CurrentInstantiationScope->InstantiatedLocalPackArg(OldParm, NewParm);
1735 // Introduce an Old -> New mapping
1736 CurrentInstantiationScope->InstantiatedLocal(OldParm, NewParm);
1739 // FIXME: OldParm may come from a FunctionProtoType, in which case CurContext
1740 // can be anything, is this right ?
1741 NewParm->setDeclContext(CurContext);
1743 NewParm->setScopeInfo(OldParm->getFunctionScopeDepth(),
1744 OldParm->getFunctionScopeIndex() + indexAdjustment);
1746 InstantiateAttrs(TemplateArgs, OldParm, NewParm);
1751 /// \brief Substitute the given template arguments into the given set of
1752 /// parameters, producing the set of parameter types that would be generated
1753 /// from such a substitution.
1754 bool Sema::SubstParmTypes(
1755 SourceLocation Loc, ArrayRef<ParmVarDecl *> Params,
1756 const FunctionProtoType::ExtParameterInfo *ExtParamInfos,
1757 const MultiLevelTemplateArgumentList &TemplateArgs,
1758 SmallVectorImpl<QualType> &ParamTypes,
1759 SmallVectorImpl<ParmVarDecl *> *OutParams,
1760 ExtParameterInfoBuilder &ParamInfos) {
1761 assert(!ActiveTemplateInstantiations.empty() &&
1762 "Cannot perform an instantiation without some context on the "
1763 "instantiation stack");
1765 TemplateInstantiator Instantiator(*this, TemplateArgs, Loc,
1767 return Instantiator.TransformFunctionTypeParams(
1768 Loc, Params, nullptr, ExtParamInfos, ParamTypes, OutParams, ParamInfos);
1771 /// \brief Perform substitution on the base class specifiers of the
1772 /// given class template specialization.
1774 /// Produces a diagnostic and returns true on error, returns false and
1775 /// attaches the instantiated base classes to the class template
1776 /// specialization if successful.
1778 Sema::SubstBaseSpecifiers(CXXRecordDecl *Instantiation,
1779 CXXRecordDecl *Pattern,
1780 const MultiLevelTemplateArgumentList &TemplateArgs) {
1781 bool Invalid = false;
1782 SmallVector<CXXBaseSpecifier*, 4> InstantiatedBases;
1783 for (const auto &Base : Pattern->bases()) {
1784 if (!Base.getType()->isDependentType()) {
1785 if (const CXXRecordDecl *RD = Base.getType()->getAsCXXRecordDecl()) {
1786 if (RD->isInvalidDecl())
1787 Instantiation->setInvalidDecl();
1789 InstantiatedBases.push_back(new (Context) CXXBaseSpecifier(Base));
1793 SourceLocation EllipsisLoc;
1794 TypeSourceInfo *BaseTypeLoc;
1795 if (Base.isPackExpansion()) {
1796 // This is a pack expansion. See whether we should expand it now, or
1797 // wait until later.
1798 SmallVector<UnexpandedParameterPack, 2> Unexpanded;
1799 collectUnexpandedParameterPacks(Base.getTypeSourceInfo()->getTypeLoc(),
1801 bool ShouldExpand = false;
1802 bool RetainExpansion = false;
1803 Optional<unsigned> NumExpansions;
1804 if (CheckParameterPacksForExpansion(Base.getEllipsisLoc(),
1805 Base.getSourceRange(),
1807 TemplateArgs, ShouldExpand,
1814 // If we should expand this pack expansion now, do so.
1816 for (unsigned I = 0; I != *NumExpansions; ++I) {
1817 Sema::ArgumentPackSubstitutionIndexRAII SubstIndex(*this, I);
1819 TypeSourceInfo *BaseTypeLoc = SubstType(Base.getTypeSourceInfo(),
1821 Base.getSourceRange().getBegin(),
1828 if (CXXBaseSpecifier *InstantiatedBase
1829 = CheckBaseSpecifier(Instantiation,
1830 Base.getSourceRange(),
1832 Base.getAccessSpecifierAsWritten(),
1835 InstantiatedBases.push_back(InstantiatedBase);
1843 // The resulting base specifier will (still) be a pack expansion.
1844 EllipsisLoc = Base.getEllipsisLoc();
1845 Sema::ArgumentPackSubstitutionIndexRAII SubstIndex(*this, -1);
1846 BaseTypeLoc = SubstType(Base.getTypeSourceInfo(),
1848 Base.getSourceRange().getBegin(),
1851 BaseTypeLoc = SubstType(Base.getTypeSourceInfo(),
1853 Base.getSourceRange().getBegin(),
1862 if (CXXBaseSpecifier *InstantiatedBase
1863 = CheckBaseSpecifier(Instantiation,
1864 Base.getSourceRange(),
1866 Base.getAccessSpecifierAsWritten(),
1869 InstantiatedBases.push_back(InstantiatedBase);
1874 if (!Invalid && AttachBaseSpecifiers(Instantiation, InstantiatedBases))
1880 // Defined via #include from SemaTemplateInstantiateDecl.cpp
1883 Attr *instantiateTemplateAttribute(const Attr *At, ASTContext &C, Sema &S,
1884 const MultiLevelTemplateArgumentList &TemplateArgs);
1888 /// \brief Instantiate the definition of a class from a given pattern.
1890 /// \param PointOfInstantiation The point of instantiation within the
1893 /// \param Instantiation is the declaration whose definition is being
1894 /// instantiated. This will be either a class template specialization
1895 /// or a member class of a class template specialization.
1897 /// \param Pattern is the pattern from which the instantiation
1898 /// occurs. This will be either the declaration of a class template or
1899 /// the declaration of a member class of a class template.
1901 /// \param TemplateArgs The template arguments to be substituted into
1904 /// \param TSK the kind of implicit or explicit instantiation to perform.
1906 /// \param Complain whether to complain if the class cannot be instantiated due
1907 /// to the lack of a definition.
1909 /// \returns true if an error occurred, false otherwise.
1911 Sema::InstantiateClass(SourceLocation PointOfInstantiation,
1912 CXXRecordDecl *Instantiation, CXXRecordDecl *Pattern,
1913 const MultiLevelTemplateArgumentList &TemplateArgs,
1914 TemplateSpecializationKind TSK,
1916 CXXRecordDecl *PatternDef
1917 = cast_or_null<CXXRecordDecl>(Pattern->getDefinition());
1918 if (DiagnoseUninstantiableTemplate(PointOfInstantiation, Instantiation,
1919 Instantiation->getInstantiatedFromMemberClass(),
1920 Pattern, PatternDef, TSK, Complain))
1922 Pattern = PatternDef;
1924 // \brief Record the point of instantiation.
1925 if (MemberSpecializationInfo *MSInfo
1926 = Instantiation->getMemberSpecializationInfo()) {
1927 MSInfo->setTemplateSpecializationKind(TSK);
1928 MSInfo->setPointOfInstantiation(PointOfInstantiation);
1929 } else if (ClassTemplateSpecializationDecl *Spec
1930 = dyn_cast<ClassTemplateSpecializationDecl>(Instantiation)) {
1931 Spec->setTemplateSpecializationKind(TSK);
1932 Spec->setPointOfInstantiation(PointOfInstantiation);
1935 InstantiatingTemplate Inst(*this, PointOfInstantiation, Instantiation);
1936 if (Inst.isInvalid())
1938 assert(!Inst.isAlreadyInstantiating() && "should have been caught by caller");
1939 PrettyDeclStackTraceEntry CrashInfo(*this, Instantiation, SourceLocation(),
1940 "instantiating class definition");
1942 // Enter the scope of this instantiation. We don't use
1943 // PushDeclContext because we don't have a scope.
1944 ContextRAII SavedContext(*this, Instantiation);
1945 EnterExpressionEvaluationContext EvalContext(*this,
1946 Sema::PotentiallyEvaluated);
1948 // If this is an instantiation of a local class, merge this local
1949 // instantiation scope with the enclosing scope. Otherwise, every
1950 // instantiation of a class has its own local instantiation scope.
1951 bool MergeWithParentScope = !Instantiation->isDefinedOutsideFunctionOrMethod();
1952 LocalInstantiationScope Scope(*this, MergeWithParentScope);
1954 // All dllexported classes created during instantiation should be fully
1955 // emitted after instantiation completes. We may not be ready to emit any
1956 // delayed classes already on the stack, so save them away and put them back
1958 decltype(DelayedDllExportClasses) ExportedClasses;
1959 std::swap(ExportedClasses, DelayedDllExportClasses);
1961 // Pull attributes from the pattern onto the instantiation.
1962 InstantiateAttrs(TemplateArgs, Pattern, Instantiation);
1964 // Start the definition of this instantiation.
1965 Instantiation->startDefinition();
1967 // The instantiation is visible here, even if it was first declared in an
1968 // unimported module.
1969 Instantiation->setHidden(false);
1971 // FIXME: This loses the as-written tag kind for an explicit instantiation.
1972 Instantiation->setTagKind(Pattern->getTagKind());
1974 // Do substitution on the base class specifiers.
1975 if (SubstBaseSpecifiers(Instantiation, Pattern, TemplateArgs))
1976 Instantiation->setInvalidDecl();
1978 TemplateDeclInstantiator Instantiator(*this, Instantiation, TemplateArgs);
1979 SmallVector<Decl*, 4> Fields;
1980 // Delay instantiation of late parsed attributes.
1981 LateInstantiatedAttrVec LateAttrs;
1982 Instantiator.enableLateAttributeInstantiation(&LateAttrs);
1984 for (auto *Member : Pattern->decls()) {
1985 // Don't instantiate members not belonging in this semantic context.
1988 // template <int i> class A {
1992 // 'class B' has the template as lexical context but semantically it is
1993 // introduced in namespace scope.
1994 if (Member->getDeclContext() != Pattern)
1997 if (Member->isInvalidDecl()) {
1998 Instantiation->setInvalidDecl();
2002 Decl *NewMember = Instantiator.Visit(Member);
2004 if (FieldDecl *Field = dyn_cast<FieldDecl>(NewMember)) {
2005 Fields.push_back(Field);
2006 } else if (EnumDecl *Enum = dyn_cast<EnumDecl>(NewMember)) {
2007 // C++11 [temp.inst]p1: The implicit instantiation of a class template
2008 // specialization causes the implicit instantiation of the definitions
2009 // of unscoped member enumerations.
2010 // Record a point of instantiation for this implicit instantiation.
2011 if (TSK == TSK_ImplicitInstantiation && !Enum->isScoped() &&
2012 Enum->isCompleteDefinition()) {
2013 MemberSpecializationInfo *MSInfo =Enum->getMemberSpecializationInfo();
2014 assert(MSInfo && "no spec info for member enum specialization");
2015 MSInfo->setTemplateSpecializationKind(TSK_ImplicitInstantiation);
2016 MSInfo->setPointOfInstantiation(PointOfInstantiation);
2018 } else if (StaticAssertDecl *SA = dyn_cast<StaticAssertDecl>(NewMember)) {
2019 if (SA->isFailed()) {
2020 // A static_assert failed. Bail out; instantiating this
2021 // class is probably not meaningful.
2022 Instantiation->setInvalidDecl();
2027 if (NewMember->isInvalidDecl())
2028 Instantiation->setInvalidDecl();
2030 // FIXME: Eventually, a NULL return will mean that one of the
2031 // instantiations was a semantic disaster, and we'll want to mark the
2032 // declaration invalid.
2033 // For now, we expect to skip some members that we can't yet handle.
2037 // Finish checking fields.
2038 ActOnFields(nullptr, Instantiation->getLocation(), Instantiation, Fields,
2039 SourceLocation(), SourceLocation(), nullptr);
2040 CheckCompletedCXXClass(Instantiation);
2042 // Default arguments are parsed, if not instantiated. We can go instantiate
2043 // default arg exprs for default constructors if necessary now.
2044 ActOnFinishCXXNonNestedClass(Instantiation);
2046 // Put back the delayed exported classes that we moved out of the way.
2047 std::swap(ExportedClasses, DelayedDllExportClasses);
2049 // Instantiate late parsed attributes, and attach them to their decls.
2050 // See Sema::InstantiateAttrs
2051 for (LateInstantiatedAttrVec::iterator I = LateAttrs.begin(),
2052 E = LateAttrs.end(); I != E; ++I) {
2053 assert(CurrentInstantiationScope == Instantiator.getStartingScope());
2054 CurrentInstantiationScope = I->Scope;
2056 // Allow 'this' within late-parsed attributes.
2057 NamedDecl *ND = dyn_cast<NamedDecl>(I->NewDecl);
2058 CXXRecordDecl *ThisContext =
2059 dyn_cast_or_null<CXXRecordDecl>(ND->getDeclContext());
2060 CXXThisScopeRAII ThisScope(*this, ThisContext, /*TypeQuals*/0,
2061 ND && ND->isCXXInstanceMember());
2064 instantiateTemplateAttribute(I->TmplAttr, Context, *this, TemplateArgs);
2065 I->NewDecl->addAttr(NewAttr);
2066 LocalInstantiationScope::deleteScopes(I->Scope,
2067 Instantiator.getStartingScope());
2069 Instantiator.disableLateAttributeInstantiation();
2072 ActOnFinishDelayedMemberInitializers(Instantiation);
2074 // FIXME: We should do something similar for explicit instantiations so they
2075 // end up in the right module.
2076 if (TSK == TSK_ImplicitInstantiation) {
2077 Instantiation->setLocation(Pattern->getLocation());
2078 Instantiation->setLocStart(Pattern->getInnerLocStart());
2079 Instantiation->setBraceRange(Pattern->getBraceRange());
2082 if (!Instantiation->isInvalidDecl()) {
2083 // Perform any dependent diagnostics from the pattern.
2084 PerformDependentDiagnostics(Pattern, TemplateArgs);
2086 // Instantiate any out-of-line class template partial
2087 // specializations now.
2088 for (TemplateDeclInstantiator::delayed_partial_spec_iterator
2089 P = Instantiator.delayed_partial_spec_begin(),
2090 PEnd = Instantiator.delayed_partial_spec_end();
2092 if (!Instantiator.InstantiateClassTemplatePartialSpecialization(
2093 P->first, P->second)) {
2094 Instantiation->setInvalidDecl();
2099 // Instantiate any out-of-line variable template partial
2100 // specializations now.
2101 for (TemplateDeclInstantiator::delayed_var_partial_spec_iterator
2102 P = Instantiator.delayed_var_partial_spec_begin(),
2103 PEnd = Instantiator.delayed_var_partial_spec_end();
2105 if (!Instantiator.InstantiateVarTemplatePartialSpecialization(
2106 P->first, P->second)) {
2107 Instantiation->setInvalidDecl();
2113 // Exit the scope of this instantiation.
2116 if (!Instantiation->isInvalidDecl()) {
2117 Consumer.HandleTagDeclDefinition(Instantiation);
2119 // Always emit the vtable for an explicit instantiation definition
2120 // of a polymorphic class template specialization.
2121 if (TSK == TSK_ExplicitInstantiationDefinition)
2122 MarkVTableUsed(PointOfInstantiation, Instantiation, true);
2125 return Instantiation->isInvalidDecl();
2128 /// \brief Instantiate the definition of an enum from a given pattern.
2130 /// \param PointOfInstantiation The point of instantiation within the
2132 /// \param Instantiation is the declaration whose definition is being
2133 /// instantiated. This will be a member enumeration of a class
2134 /// temploid specialization, or a local enumeration within a
2135 /// function temploid specialization.
2136 /// \param Pattern The templated declaration from which the instantiation
2138 /// \param TemplateArgs The template arguments to be substituted into
2140 /// \param TSK The kind of implicit or explicit instantiation to perform.
2142 /// \return \c true if an error occurred, \c false otherwise.
2143 bool Sema::InstantiateEnum(SourceLocation PointOfInstantiation,
2144 EnumDecl *Instantiation, EnumDecl *Pattern,
2145 const MultiLevelTemplateArgumentList &TemplateArgs,
2146 TemplateSpecializationKind TSK) {
2147 EnumDecl *PatternDef = Pattern->getDefinition();
2148 if (DiagnoseUninstantiableTemplate(PointOfInstantiation, Instantiation,
2149 Instantiation->getInstantiatedFromMemberEnum(),
2150 Pattern, PatternDef, TSK,/*Complain*/true))
2152 Pattern = PatternDef;
2154 // Record the point of instantiation.
2155 if (MemberSpecializationInfo *MSInfo
2156 = Instantiation->getMemberSpecializationInfo()) {
2157 MSInfo->setTemplateSpecializationKind(TSK);
2158 MSInfo->setPointOfInstantiation(PointOfInstantiation);
2161 InstantiatingTemplate Inst(*this, PointOfInstantiation, Instantiation);
2162 if (Inst.isInvalid())
2164 if (Inst.isAlreadyInstantiating())
2166 PrettyDeclStackTraceEntry CrashInfo(*this, Instantiation, SourceLocation(),
2167 "instantiating enum definition");
2169 // The instantiation is visible here, even if it was first declared in an
2170 // unimported module.
2171 Instantiation->setHidden(false);
2173 // Enter the scope of this instantiation. We don't use
2174 // PushDeclContext because we don't have a scope.
2175 ContextRAII SavedContext(*this, Instantiation);
2176 EnterExpressionEvaluationContext EvalContext(*this,
2177 Sema::PotentiallyEvaluated);
2179 LocalInstantiationScope Scope(*this, /*MergeWithParentScope*/true);
2181 // Pull attributes from the pattern onto the instantiation.
2182 InstantiateAttrs(TemplateArgs, Pattern, Instantiation);
2184 TemplateDeclInstantiator Instantiator(*this, Instantiation, TemplateArgs);
2185 Instantiator.InstantiateEnumDefinition(Instantiation, Pattern);
2187 // Exit the scope of this instantiation.
2190 return Instantiation->isInvalidDecl();
2194 /// \brief Instantiate the definition of a field from the given pattern.
2196 /// \param PointOfInstantiation The point of instantiation within the
2198 /// \param Instantiation is the declaration whose definition is being
2199 /// instantiated. This will be a class of a class temploid
2200 /// specialization, or a local enumeration within a function temploid
2202 /// \param Pattern The templated declaration from which the instantiation
2204 /// \param TemplateArgs The template arguments to be substituted into
2207 /// \return \c true if an error occurred, \c false otherwise.
2208 bool Sema::InstantiateInClassInitializer(
2209 SourceLocation PointOfInstantiation, FieldDecl *Instantiation,
2210 FieldDecl *Pattern, const MultiLevelTemplateArgumentList &TemplateArgs) {
2211 // If there is no initializer, we don't need to do anything.
2212 if (!Pattern->hasInClassInitializer())
2215 assert(Instantiation->getInClassInitStyle() ==
2216 Pattern->getInClassInitStyle() &&
2217 "pattern and instantiation disagree about init style");
2219 // Error out if we haven't parsed the initializer of the pattern yet because
2220 // we are waiting for the closing brace of the outer class.
2221 Expr *OldInit = Pattern->getInClassInitializer();
2223 RecordDecl *PatternRD = Pattern->getParent();
2224 RecordDecl *OutermostClass = PatternRD->getOuterLexicalRecordContext();
2225 Diag(PointOfInstantiation,
2226 diag::err_in_class_initializer_not_yet_parsed)
2227 << OutermostClass << Pattern;
2228 Diag(Pattern->getLocEnd(), diag::note_in_class_initializer_not_yet_parsed);
2229 Instantiation->setInvalidDecl();
2233 InstantiatingTemplate Inst(*this, PointOfInstantiation, Instantiation);
2234 if (Inst.isInvalid())
2236 if (Inst.isAlreadyInstantiating()) {
2237 // Error out if we hit an instantiation cycle for this initializer.
2238 Diag(PointOfInstantiation, diag::err_in_class_initializer_cycle)
2242 PrettyDeclStackTraceEntry CrashInfo(*this, Instantiation, SourceLocation(),
2243 "instantiating default member init");
2245 // Enter the scope of this instantiation. We don't use PushDeclContext because
2246 // we don't have a scope.
2247 ContextRAII SavedContext(*this, Instantiation->getParent());
2248 EnterExpressionEvaluationContext EvalContext(*this,
2249 Sema::PotentiallyEvaluated);
2251 LocalInstantiationScope Scope(*this, true);
2253 // Instantiate the initializer.
2254 ActOnStartCXXInClassMemberInitializer();
2255 CXXThisScopeRAII ThisScope(*this, Instantiation->getParent(), /*TypeQuals=*/0);
2257 ExprResult NewInit = SubstInitializer(OldInit, TemplateArgs,
2258 /*CXXDirectInit=*/false);
2259 Expr *Init = NewInit.get();
2260 assert((!Init || !isa<ParenListExpr>(Init)) && "call-style init in class");
2261 ActOnFinishCXXInClassMemberInitializer(
2262 Instantiation, Init ? Init->getLocStart() : SourceLocation(), Init);
2264 if (auto *L = getASTMutationListener())
2265 L->DefaultMemberInitializerInstantiated(Instantiation);
2267 // Return true if the in-class initializer is still missing.
2268 return !Instantiation->getInClassInitializer();
2272 /// \brief A partial specialization whose template arguments have matched
2273 /// a given template-id.
2274 struct PartialSpecMatchResult {
2275 ClassTemplatePartialSpecializationDecl *Partial;
2276 TemplateArgumentList *Args;
2280 /// Get the instantiation pattern to use to instantiate the definition of a
2281 /// given ClassTemplateSpecializationDecl (either the pattern of the primary
2282 /// template or of a partial specialization).
2283 static CXXRecordDecl *
2284 getPatternForClassTemplateSpecialization(
2285 Sema &S, SourceLocation PointOfInstantiation,
2286 ClassTemplateSpecializationDecl *ClassTemplateSpec,
2287 TemplateSpecializationKind TSK, bool Complain) {
2288 Sema::InstantiatingTemplate Inst(S, PointOfInstantiation, ClassTemplateSpec);
2289 if (Inst.isInvalid() || Inst.isAlreadyInstantiating())
2292 ClassTemplateDecl *Template = ClassTemplateSpec->getSpecializedTemplate();
2293 CXXRecordDecl *Pattern = nullptr;
2295 // C++ [temp.class.spec.match]p1:
2296 // When a class template is used in a context that requires an
2297 // instantiation of the class, it is necessary to determine
2298 // whether the instantiation is to be generated using the primary
2299 // template or one of the partial specializations. This is done by
2300 // matching the template arguments of the class template
2301 // specialization with the template argument lists of the partial
2303 typedef PartialSpecMatchResult MatchResult;
2304 SmallVector<MatchResult, 4> Matched;
2305 SmallVector<ClassTemplatePartialSpecializationDecl *, 4> PartialSpecs;
2306 Template->getPartialSpecializations(PartialSpecs);
2307 TemplateSpecCandidateSet FailedCandidates(PointOfInstantiation);
2308 for (unsigned I = 0, N = PartialSpecs.size(); I != N; ++I) {
2309 ClassTemplatePartialSpecializationDecl *Partial = PartialSpecs[I];
2310 TemplateDeductionInfo Info(FailedCandidates.getLocation());
2311 if (Sema::TemplateDeductionResult Result = S.DeduceTemplateArguments(
2312 Partial, ClassTemplateSpec->getTemplateArgs(), Info)) {
2313 // Store the failed-deduction information for use in diagnostics, later.
2314 // TODO: Actually use the failed-deduction info?
2315 FailedCandidates.addCandidate().set(
2316 DeclAccessPair::make(Template, AS_public), Partial,
2317 MakeDeductionFailureInfo(S.Context, Result, Info));
2320 Matched.push_back(PartialSpecMatchResult());
2321 Matched.back().Partial = Partial;
2322 Matched.back().Args = Info.take();
2326 // If we're dealing with a member template where the template parameters
2327 // have been instantiated, this provides the original template parameters
2328 // from which the member template's parameters were instantiated.
2330 if (Matched.size() >= 1) {
2331 SmallVectorImpl<MatchResult>::iterator Best = Matched.begin();
2332 if (Matched.size() == 1) {
2333 // -- If exactly one matching specialization is found, the
2334 // instantiation is generated from that specialization.
2335 // We don't need to do anything for this.
2337 // -- If more than one matching specialization is found, the
2338 // partial order rules (14.5.4.2) are used to determine
2339 // whether one of the specializations is more specialized
2340 // than the others. If none of the specializations is more
2341 // specialized than all of the other matching
2342 // specializations, then the use of the class template is
2343 // ambiguous and the program is ill-formed.
2344 for (SmallVectorImpl<MatchResult>::iterator P = Best + 1,
2345 PEnd = Matched.end();
2347 if (S.getMoreSpecializedPartialSpecialization(
2348 P->Partial, Best->Partial, PointOfInstantiation) == P->Partial)
2352 // Determine if the best partial specialization is more specialized than
2354 bool Ambiguous = false;
2355 for (SmallVectorImpl<MatchResult>::iterator P = Matched.begin(),
2356 PEnd = Matched.end();
2359 S.getMoreSpecializedPartialSpecialization(P->Partial, Best->Partial,
2360 PointOfInstantiation) !=
2368 // Partial ordering did not produce a clear winner. Complain.
2370 ClassTemplateSpec->setInvalidDecl();
2371 S.Diag(PointOfInstantiation, diag::err_partial_spec_ordering_ambiguous)
2372 << ClassTemplateSpec;
2374 // Print the matching partial specializations.
2375 for (SmallVectorImpl<MatchResult>::iterator P = Matched.begin(),
2376 PEnd = Matched.end();
2378 S.Diag(P->Partial->getLocation(), diag::note_partial_spec_match)
2379 << S.getTemplateArgumentBindingsText(
2380 P->Partial->getTemplateParameters(), *P->Args);
2386 // Instantiate using the best class template partial specialization.
2387 ClassTemplatePartialSpecializationDecl *OrigPartialSpec = Best->Partial;
2388 while (OrigPartialSpec->getInstantiatedFromMember()) {
2389 // If we've found an explicit specialization of this class template,
2390 // stop here and use that as the pattern.
2391 if (OrigPartialSpec->isMemberSpecialization())
2394 OrigPartialSpec = OrigPartialSpec->getInstantiatedFromMember();
2397 Pattern = OrigPartialSpec;
2398 ClassTemplateSpec->setInstantiationOf(Best->Partial, Best->Args);
2400 // -- If no matches are found, the instantiation is generated
2401 // from the primary template.
2402 ClassTemplateDecl *OrigTemplate = Template;
2403 while (OrigTemplate->getInstantiatedFromMemberTemplate()) {
2404 // If we've found an explicit specialization of this class template,
2405 // stop here and use that as the pattern.
2406 if (OrigTemplate->isMemberSpecialization())
2409 OrigTemplate = OrigTemplate->getInstantiatedFromMemberTemplate();
2412 Pattern = OrigTemplate->getTemplatedDecl();
2418 bool Sema::InstantiateClassTemplateSpecialization(
2419 SourceLocation PointOfInstantiation,
2420 ClassTemplateSpecializationDecl *ClassTemplateSpec,
2421 TemplateSpecializationKind TSK, bool Complain) {
2422 // Perform the actual instantiation on the canonical declaration.
2423 ClassTemplateSpec = cast<ClassTemplateSpecializationDecl>(
2424 ClassTemplateSpec->getCanonicalDecl());
2425 if (ClassTemplateSpec->isInvalidDecl())
2428 CXXRecordDecl *Pattern = getPatternForClassTemplateSpecialization(
2429 *this, PointOfInstantiation, ClassTemplateSpec, TSK, Complain);
2433 return InstantiateClass(PointOfInstantiation, ClassTemplateSpec, Pattern,
2434 getTemplateInstantiationArgs(ClassTemplateSpec), TSK,
2438 /// \brief Instantiates the definitions of all of the member
2439 /// of the given class, which is an instantiation of a class template
2440 /// or a member class of a template.
2442 Sema::InstantiateClassMembers(SourceLocation PointOfInstantiation,
2443 CXXRecordDecl *Instantiation,
2444 const MultiLevelTemplateArgumentList &TemplateArgs,
2445 TemplateSpecializationKind TSK) {
2446 // FIXME: We need to notify the ASTMutationListener that we did all of these
2447 // things, in case we have an explicit instantiation definition in a PCM, a
2448 // module, or preamble, and the declaration is in an imported AST.
2450 (TSK == TSK_ExplicitInstantiationDefinition ||
2451 TSK == TSK_ExplicitInstantiationDeclaration ||
2452 (TSK == TSK_ImplicitInstantiation && Instantiation->isLocalClass())) &&
2453 "Unexpected template specialization kind!");
2454 for (auto *D : Instantiation->decls()) {
2455 bool SuppressNew = false;
2456 if (auto *Function = dyn_cast<FunctionDecl>(D)) {
2457 if (FunctionDecl *Pattern
2458 = Function->getInstantiatedFromMemberFunction()) {
2459 MemberSpecializationInfo *MSInfo
2460 = Function->getMemberSpecializationInfo();
2461 assert(MSInfo && "No member specialization information?");
2462 if (MSInfo->getTemplateSpecializationKind()
2463 == TSK_ExplicitSpecialization)
2466 if (CheckSpecializationInstantiationRedecl(PointOfInstantiation, TSK,
2468 MSInfo->getTemplateSpecializationKind(),
2469 MSInfo->getPointOfInstantiation(),
2474 // C++11 [temp.explicit]p8:
2475 // An explicit instantiation definition that names a class template
2476 // specialization explicitly instantiates the class template
2477 // specialization and is only an explicit instantiation definition
2478 // of members whose definition is visible at the point of
2480 if (TSK == TSK_ExplicitInstantiationDefinition && !Pattern->isDefined())
2483 Function->setTemplateSpecializationKind(TSK, PointOfInstantiation);
2485 if (Function->isDefined()) {
2486 // Let the ASTConsumer know that this function has been explicitly
2487 // instantiated now, and its linkage might have changed.
2488 Consumer.HandleTopLevelDecl(DeclGroupRef(Function));
2489 } else if (TSK == TSK_ExplicitInstantiationDefinition) {
2490 InstantiateFunctionDefinition(PointOfInstantiation, Function);
2491 } else if (TSK == TSK_ImplicitInstantiation) {
2492 PendingLocalImplicitInstantiations.push_back(
2493 std::make_pair(Function, PointOfInstantiation));
2496 } else if (auto *Var = dyn_cast<VarDecl>(D)) {
2497 if (isa<VarTemplateSpecializationDecl>(Var))
2500 if (Var->isStaticDataMember()) {
2501 MemberSpecializationInfo *MSInfo = Var->getMemberSpecializationInfo();
2502 assert(MSInfo && "No member specialization information?");
2503 if (MSInfo->getTemplateSpecializationKind()
2504 == TSK_ExplicitSpecialization)
2507 if (CheckSpecializationInstantiationRedecl(PointOfInstantiation, TSK,
2509 MSInfo->getTemplateSpecializationKind(),
2510 MSInfo->getPointOfInstantiation(),
2515 if (TSK == TSK_ExplicitInstantiationDefinition) {
2516 // C++0x [temp.explicit]p8:
2517 // An explicit instantiation definition that names a class template
2518 // specialization explicitly instantiates the class template
2519 // specialization and is only an explicit instantiation definition
2520 // of members whose definition is visible at the point of
2522 if (!Var->getInstantiatedFromStaticDataMember()->getDefinition())
2525 Var->setTemplateSpecializationKind(TSK, PointOfInstantiation);
2526 InstantiateStaticDataMemberDefinition(PointOfInstantiation, Var);
2528 Var->setTemplateSpecializationKind(TSK, PointOfInstantiation);
2531 } else if (auto *Record = dyn_cast<CXXRecordDecl>(D)) {
2532 // Always skip the injected-class-name, along with any
2533 // redeclarations of nested classes, since both would cause us
2534 // to try to instantiate the members of a class twice.
2535 // Skip closure types; they'll get instantiated when we instantiate
2536 // the corresponding lambda-expression.
2537 if (Record->isInjectedClassName() || Record->getPreviousDecl() ||
2541 MemberSpecializationInfo *MSInfo = Record->getMemberSpecializationInfo();
2542 assert(MSInfo && "No member specialization information?");
2544 if (MSInfo->getTemplateSpecializationKind()
2545 == TSK_ExplicitSpecialization)
2548 if (Context.getTargetInfo().getCXXABI().isMicrosoft() &&
2549 TSK == TSK_ExplicitInstantiationDeclaration) {
2550 // In MSVC mode, explicit instantiation decl of the outer class doesn't
2551 // affect the inner class.
2555 if (CheckSpecializationInstantiationRedecl(PointOfInstantiation, TSK,
2557 MSInfo->getTemplateSpecializationKind(),
2558 MSInfo->getPointOfInstantiation(),
2563 CXXRecordDecl *Pattern = Record->getInstantiatedFromMemberClass();
2564 assert(Pattern && "Missing instantiated-from-template information");
2566 if (!Record->getDefinition()) {
2567 if (!Pattern->getDefinition()) {
2568 // C++0x [temp.explicit]p8:
2569 // An explicit instantiation definition that names a class template
2570 // specialization explicitly instantiates the class template
2571 // specialization and is only an explicit instantiation definition
2572 // of members whose definition is visible at the point of
2574 if (TSK == TSK_ExplicitInstantiationDeclaration) {
2575 MSInfo->setTemplateSpecializationKind(TSK);
2576 MSInfo->setPointOfInstantiation(PointOfInstantiation);
2582 InstantiateClass(PointOfInstantiation, Record, Pattern,
2586 if (TSK == TSK_ExplicitInstantiationDefinition &&
2587 Record->getTemplateSpecializationKind() ==
2588 TSK_ExplicitInstantiationDeclaration) {
2589 Record->setTemplateSpecializationKind(TSK);
2590 MarkVTableUsed(PointOfInstantiation, Record, true);
2594 Pattern = cast_or_null<CXXRecordDecl>(Record->getDefinition());
2596 InstantiateClassMembers(PointOfInstantiation, Pattern, TemplateArgs,
2598 } else if (auto *Enum = dyn_cast<EnumDecl>(D)) {
2599 MemberSpecializationInfo *MSInfo = Enum->getMemberSpecializationInfo();
2600 assert(MSInfo && "No member specialization information?");
2602 if (MSInfo->getTemplateSpecializationKind()
2603 == TSK_ExplicitSpecialization)
2606 if (CheckSpecializationInstantiationRedecl(
2607 PointOfInstantiation, TSK, Enum,
2608 MSInfo->getTemplateSpecializationKind(),
2609 MSInfo->getPointOfInstantiation(), SuppressNew) ||
2613 if (Enum->getDefinition())
2616 EnumDecl *Pattern = Enum->getTemplateInstantiationPattern();
2617 assert(Pattern && "Missing instantiated-from-template information");
2619 if (TSK == TSK_ExplicitInstantiationDefinition) {
2620 if (!Pattern->getDefinition())
2623 InstantiateEnum(PointOfInstantiation, Enum, Pattern, TemplateArgs, TSK);
2625 MSInfo->setTemplateSpecializationKind(TSK);
2626 MSInfo->setPointOfInstantiation(PointOfInstantiation);
2628 } else if (auto *Field = dyn_cast<FieldDecl>(D)) {
2629 // No need to instantiate in-class initializers during explicit
2631 if (Field->hasInClassInitializer() && TSK == TSK_ImplicitInstantiation) {
2632 CXXRecordDecl *ClassPattern =
2633 Instantiation->getTemplateInstantiationPattern();
2634 DeclContext::lookup_result Lookup =
2635 ClassPattern->lookup(Field->getDeclName());
2636 FieldDecl *Pattern = cast<FieldDecl>(Lookup.front());
2637 InstantiateInClassInitializer(PointOfInstantiation, Field, Pattern,
2644 /// \brief Instantiate the definitions of all of the members of the
2645 /// given class template specialization, which was named as part of an
2646 /// explicit instantiation.
2648 Sema::InstantiateClassTemplateSpecializationMembers(
2649 SourceLocation PointOfInstantiation,
2650 ClassTemplateSpecializationDecl *ClassTemplateSpec,
2651 TemplateSpecializationKind TSK) {
2652 // C++0x [temp.explicit]p7:
2653 // An explicit instantiation that names a class template
2654 // specialization is an explicit instantion of the same kind
2655 // (declaration or definition) of each of its members (not
2656 // including members inherited from base classes) that has not
2657 // been previously explicitly specialized in the translation unit
2658 // containing the explicit instantiation, except as described
2660 InstantiateClassMembers(PointOfInstantiation, ClassTemplateSpec,
2661 getTemplateInstantiationArgs(ClassTemplateSpec),
2666 Sema::SubstStmt(Stmt *S, const MultiLevelTemplateArgumentList &TemplateArgs) {
2670 TemplateInstantiator Instantiator(*this, TemplateArgs,
2673 return Instantiator.TransformStmt(S);
2677 Sema::SubstExpr(Expr *E, const MultiLevelTemplateArgumentList &TemplateArgs) {
2681 TemplateInstantiator Instantiator(*this, TemplateArgs,
2684 return Instantiator.TransformExpr(E);
2687 ExprResult Sema::SubstInitializer(Expr *Init,
2688 const MultiLevelTemplateArgumentList &TemplateArgs,
2689 bool CXXDirectInit) {
2690 TemplateInstantiator Instantiator(*this, TemplateArgs,
2693 return Instantiator.TransformInitializer(Init, CXXDirectInit);
2696 bool Sema::SubstExprs(ArrayRef<Expr *> Exprs, bool IsCall,
2697 const MultiLevelTemplateArgumentList &TemplateArgs,
2698 SmallVectorImpl<Expr *> &Outputs) {
2702 TemplateInstantiator Instantiator(*this, TemplateArgs,
2705 return Instantiator.TransformExprs(Exprs.data(), Exprs.size(),
2709 NestedNameSpecifierLoc
2710 Sema::SubstNestedNameSpecifierLoc(NestedNameSpecifierLoc NNS,
2711 const MultiLevelTemplateArgumentList &TemplateArgs) {
2713 return NestedNameSpecifierLoc();
2715 TemplateInstantiator Instantiator(*this, TemplateArgs, NNS.getBeginLoc(),
2717 return Instantiator.TransformNestedNameSpecifierLoc(NNS);
2720 /// \brief Do template substitution on declaration name info.
2722 Sema::SubstDeclarationNameInfo(const DeclarationNameInfo &NameInfo,
2723 const MultiLevelTemplateArgumentList &TemplateArgs) {
2724 TemplateInstantiator Instantiator(*this, TemplateArgs, NameInfo.getLoc(),
2725 NameInfo.getName());
2726 return Instantiator.TransformDeclarationNameInfo(NameInfo);
2730 Sema::SubstTemplateName(NestedNameSpecifierLoc QualifierLoc,
2731 TemplateName Name, SourceLocation Loc,
2732 const MultiLevelTemplateArgumentList &TemplateArgs) {
2733 TemplateInstantiator Instantiator(*this, TemplateArgs, Loc,
2736 SS.Adopt(QualifierLoc);
2737 return Instantiator.TransformTemplateName(SS, Name, Loc);
2740 bool Sema::Subst(const TemplateArgumentLoc *Args, unsigned NumArgs,
2741 TemplateArgumentListInfo &Result,
2742 const MultiLevelTemplateArgumentList &TemplateArgs) {
2743 TemplateInstantiator Instantiator(*this, TemplateArgs, SourceLocation(),
2746 return Instantiator.TransformTemplateArguments(Args, NumArgs, Result);
2749 static const Decl *getCanonicalParmVarDecl(const Decl *D) {
2750 // When storing ParmVarDecls in the local instantiation scope, we always
2751 // want to use the ParmVarDecl from the canonical function declaration,
2752 // since the map is then valid for any redeclaration or definition of that
2754 if (const ParmVarDecl *PV = dyn_cast<ParmVarDecl>(D)) {
2755 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(PV->getDeclContext())) {
2756 unsigned i = PV->getFunctionScopeIndex();
2757 // This parameter might be from a freestanding function type within the
2758 // function and isn't necessarily referring to one of FD's parameters.
2759 if (FD->getParamDecl(i) == PV)
2760 return FD->getCanonicalDecl()->getParamDecl(i);
2767 llvm::PointerUnion<Decl *, LocalInstantiationScope::DeclArgumentPack *> *
2768 LocalInstantiationScope::findInstantiationOf(const Decl *D) {
2769 D = getCanonicalParmVarDecl(D);
2770 for (LocalInstantiationScope *Current = this; Current;
2771 Current = Current->Outer) {
2773 // Check if we found something within this scope.
2774 const Decl *CheckD = D;
2776 LocalDeclsMap::iterator Found = Current->LocalDecls.find(CheckD);
2777 if (Found != Current->LocalDecls.end())
2778 return &Found->second;
2780 // If this is a tag declaration, it's possible that we need to look for
2781 // a previous declaration.
2782 if (const TagDecl *Tag = dyn_cast<TagDecl>(CheckD))
2783 CheckD = Tag->getPreviousDecl();
2788 // If we aren't combined with our outer scope, we're done.
2789 if (!Current->CombineWithOuterScope)
2793 // If we're performing a partial substitution during template argument
2794 // deduction, we may not have values for template parameters yet.
2795 if (isa<NonTypeTemplateParmDecl>(D) || isa<TemplateTypeParmDecl>(D) ||
2796 isa<TemplateTemplateParmDecl>(D))
2799 // Local types referenced prior to definition may require instantiation.
2800 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(D))
2801 if (RD->isLocalClass())
2804 // Enumeration types referenced prior to definition may appear as a result of
2806 if (isa<EnumDecl>(D))
2809 // If we didn't find the decl, then we either have a sema bug, or we have a
2810 // forward reference to a label declaration. Return null to indicate that
2811 // we have an uninstantiated label.
2812 assert(isa<LabelDecl>(D) && "declaration not instantiated in this scope");
2816 void LocalInstantiationScope::InstantiatedLocal(const Decl *D, Decl *Inst) {
2817 D = getCanonicalParmVarDecl(D);
2818 llvm::PointerUnion<Decl *, DeclArgumentPack *> &Stored = LocalDecls[D];
2819 if (Stored.isNull()) {
2821 // It should not be present in any surrounding scope either.
2822 LocalInstantiationScope *Current = this;
2823 while (Current->CombineWithOuterScope && Current->Outer) {
2824 Current = Current->Outer;
2825 assert(Current->LocalDecls.find(D) == Current->LocalDecls.end() &&
2826 "Instantiated local in inner and outer scopes");
2830 } else if (DeclArgumentPack *Pack = Stored.dyn_cast<DeclArgumentPack *>()) {
2831 Pack->push_back(cast<ParmVarDecl>(Inst));
2833 assert(Stored.get<Decl *>() == Inst && "Already instantiated this local");
2837 void LocalInstantiationScope::InstantiatedLocalPackArg(const Decl *D,
2838 ParmVarDecl *Inst) {
2839 D = getCanonicalParmVarDecl(D);
2840 DeclArgumentPack *Pack = LocalDecls[D].get<DeclArgumentPack *>();
2841 Pack->push_back(Inst);
2844 void LocalInstantiationScope::MakeInstantiatedLocalArgPack(const Decl *D) {
2846 // This should be the first time we've been told about this decl.
2847 for (LocalInstantiationScope *Current = this;
2848 Current && Current->CombineWithOuterScope; Current = Current->Outer)
2849 assert(Current->LocalDecls.find(D) == Current->LocalDecls.end() &&
2850 "Creating local pack after instantiation of local");
2853 D = getCanonicalParmVarDecl(D);
2854 llvm::PointerUnion<Decl *, DeclArgumentPack *> &Stored = LocalDecls[D];
2855 DeclArgumentPack *Pack = new DeclArgumentPack;
2857 ArgumentPacks.push_back(Pack);
2860 void LocalInstantiationScope::SetPartiallySubstitutedPack(NamedDecl *Pack,
2861 const TemplateArgument *ExplicitArgs,
2862 unsigned NumExplicitArgs) {
2863 assert((!PartiallySubstitutedPack || PartiallySubstitutedPack == Pack) &&
2864 "Already have a partially-substituted pack");
2865 assert((!PartiallySubstitutedPack
2866 || NumArgsInPartiallySubstitutedPack == NumExplicitArgs) &&
2867 "Wrong number of arguments in partially-substituted pack");
2868 PartiallySubstitutedPack = Pack;
2869 ArgsInPartiallySubstitutedPack = ExplicitArgs;
2870 NumArgsInPartiallySubstitutedPack = NumExplicitArgs;
2873 NamedDecl *LocalInstantiationScope::getPartiallySubstitutedPack(
2874 const TemplateArgument **ExplicitArgs,
2875 unsigned *NumExplicitArgs) const {
2877 *ExplicitArgs = nullptr;
2878 if (NumExplicitArgs)
2879 *NumExplicitArgs = 0;
2881 for (const LocalInstantiationScope *Current = this; Current;
2882 Current = Current->Outer) {
2883 if (Current->PartiallySubstitutedPack) {
2885 *ExplicitArgs = Current->ArgsInPartiallySubstitutedPack;
2886 if (NumExplicitArgs)
2887 *NumExplicitArgs = Current->NumArgsInPartiallySubstitutedPack;
2889 return Current->PartiallySubstitutedPack;
2892 if (!Current->CombineWithOuterScope)