clang  7.0.0svn
SemaTemplateInstantiateDecl.cpp
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1 //===--- SemaTemplateInstantiateDecl.cpp - C++ Template Decl Instantiation ===/
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //===----------------------------------------------------------------------===/
8 //
9 // This file implements C++ template instantiation for declarations.
10 //
11 //===----------------------------------------------------------------------===/
13 #include "clang/AST/ASTConsumer.h"
14 #include "clang/AST/ASTContext.h"
16 #include "clang/AST/DeclTemplate.h"
17 #include "clang/AST/DeclVisitor.h"
19 #include "clang/AST/Expr.h"
20 #include "clang/AST/ExprCXX.h"
22 #include "clang/AST/TypeLoc.h"
24 #include "clang/Sema/Lookup.h"
25 #include "clang/Sema/Template.h"
27 
28 using namespace clang;
29 
30 static bool isDeclWithinFunction(const Decl *D) {
31  const DeclContext *DC = D->getDeclContext();
32  if (DC->isFunctionOrMethod())
33  return true;
34 
35  if (DC->isRecord())
36  return cast<CXXRecordDecl>(DC)->isLocalClass();
37 
38  return false;
39 }
40 
41 template<typename DeclT>
42 static bool SubstQualifier(Sema &SemaRef, const DeclT *OldDecl, DeclT *NewDecl,
43  const MultiLevelTemplateArgumentList &TemplateArgs) {
44  if (!OldDecl->getQualifierLoc())
45  return false;
46 
47  assert((NewDecl->getFriendObjectKind() ||
48  !OldDecl->getLexicalDeclContext()->isDependentContext()) &&
49  "non-friend with qualified name defined in dependent context");
50  Sema::ContextRAII SavedContext(
51  SemaRef,
52  const_cast<DeclContext *>(NewDecl->getFriendObjectKind()
53  ? NewDecl->getLexicalDeclContext()
54  : OldDecl->getLexicalDeclContext()));
55 
56  NestedNameSpecifierLoc NewQualifierLoc
57  = SemaRef.SubstNestedNameSpecifierLoc(OldDecl->getQualifierLoc(),
58  TemplateArgs);
59 
60  if (!NewQualifierLoc)
61  return true;
62 
63  NewDecl->setQualifierInfo(NewQualifierLoc);
64  return false;
65 }
66 
68  DeclaratorDecl *NewDecl) {
69  return ::SubstQualifier(SemaRef, OldDecl, NewDecl, TemplateArgs);
70 }
71 
73  TagDecl *NewDecl) {
74  return ::SubstQualifier(SemaRef, OldDecl, NewDecl, TemplateArgs);
75 }
76 
77 // Include attribute instantiation code.
78 #include "clang/Sema/AttrTemplateInstantiate.inc"
79 
81  Sema &S, const MultiLevelTemplateArgumentList &TemplateArgs,
82  const AlignedAttr *Aligned, Decl *New, bool IsPackExpansion) {
83  if (Aligned->isAlignmentExpr()) {
84  // The alignment expression is a constant expression.
87  ExprResult Result = S.SubstExpr(Aligned->getAlignmentExpr(), TemplateArgs);
88  if (!Result.isInvalid())
89  S.AddAlignedAttr(Aligned->getLocation(), New, Result.getAs<Expr>(),
90  Aligned->getSpellingListIndex(), IsPackExpansion);
91  } else {
92  TypeSourceInfo *Result = S.SubstType(Aligned->getAlignmentType(),
93  TemplateArgs, Aligned->getLocation(),
94  DeclarationName());
95  if (Result)
96  S.AddAlignedAttr(Aligned->getLocation(), New, Result,
97  Aligned->getSpellingListIndex(), IsPackExpansion);
98  }
99 }
100 
102  Sema &S, const MultiLevelTemplateArgumentList &TemplateArgs,
103  const AlignedAttr *Aligned, Decl *New) {
104  if (!Aligned->isPackExpansion()) {
105  instantiateDependentAlignedAttr(S, TemplateArgs, Aligned, New, false);
106  return;
107  }
108 
110  if (Aligned->isAlignmentExpr())
111  S.collectUnexpandedParameterPacks(Aligned->getAlignmentExpr(),
112  Unexpanded);
113  else
114  S.collectUnexpandedParameterPacks(Aligned->getAlignmentType()->getTypeLoc(),
115  Unexpanded);
116  assert(!Unexpanded.empty() && "Pack expansion without parameter packs?");
117 
118  // Determine whether we can expand this attribute pack yet.
119  bool Expand = true, RetainExpansion = false;
120  Optional<unsigned> NumExpansions;
121  // FIXME: Use the actual location of the ellipsis.
122  SourceLocation EllipsisLoc = Aligned->getLocation();
123  if (S.CheckParameterPacksForExpansion(EllipsisLoc, Aligned->getRange(),
124  Unexpanded, TemplateArgs, Expand,
125  RetainExpansion, NumExpansions))
126  return;
127 
128  if (!Expand) {
129  Sema::ArgumentPackSubstitutionIndexRAII SubstIndex(S, -1);
130  instantiateDependentAlignedAttr(S, TemplateArgs, Aligned, New, true);
131  } else {
132  for (unsigned I = 0; I != *NumExpansions; ++I) {
134  instantiateDependentAlignedAttr(S, TemplateArgs, Aligned, New, false);
135  }
136  }
137 }
138 
140  Sema &S, const MultiLevelTemplateArgumentList &TemplateArgs,
141  const AssumeAlignedAttr *Aligned, Decl *New) {
142  // The alignment expression is a constant expression.
145 
146  Expr *E, *OE = nullptr;
147  ExprResult Result = S.SubstExpr(Aligned->getAlignment(), TemplateArgs);
148  if (Result.isInvalid())
149  return;
150  E = Result.getAs<Expr>();
151 
152  if (Aligned->getOffset()) {
153  Result = S.SubstExpr(Aligned->getOffset(), TemplateArgs);
154  if (Result.isInvalid())
155  return;
156  OE = Result.getAs<Expr>();
157  }
158 
159  S.AddAssumeAlignedAttr(Aligned->getLocation(), New, E, OE,
160  Aligned->getSpellingListIndex());
161 }
162 
164  Sema &S, const MultiLevelTemplateArgumentList &TemplateArgs,
165  const AlignValueAttr *Aligned, Decl *New) {
166  // The alignment expression is a constant expression.
169  ExprResult Result = S.SubstExpr(Aligned->getAlignment(), TemplateArgs);
170  if (!Result.isInvalid())
171  S.AddAlignValueAttr(Aligned->getLocation(), New, Result.getAs<Expr>(),
172  Aligned->getSpellingListIndex());
173 }
174 
176  Sema &S, const MultiLevelTemplateArgumentList &TemplateArgs,
177  const AllocAlignAttr *Align, Decl *New) {
178  Expr *Param = IntegerLiteral::Create(
179  S.getASTContext(),
180  llvm::APInt(64, Align->getParamIndex().getSourceIndex()),
181  S.getASTContext().UnsignedLongLongTy, Align->getLocation());
182  S.AddAllocAlignAttr(Align->getLocation(), New, Param,
183  Align->getSpellingListIndex());
184 }
185 
187  Sema &S, const MultiLevelTemplateArgumentList &TemplateArgs,
188  const Attr *A, Expr *OldCond, const Decl *Tmpl, FunctionDecl *New) {
189  Expr *Cond = nullptr;
190  {
191  Sema::ContextRAII SwitchContext(S, New);
194  ExprResult Result = S.SubstExpr(OldCond, TemplateArgs);
195  if (Result.isInvalid())
196  return nullptr;
197  Cond = Result.getAs<Expr>();
198  }
199  if (!Cond->isTypeDependent()) {
200  ExprResult Converted = S.PerformContextuallyConvertToBool(Cond);
201  if (Converted.isInvalid())
202  return nullptr;
203  Cond = Converted.get();
204  }
205 
207  if (OldCond->isValueDependent() && !Cond->isValueDependent() &&
208  !Expr::isPotentialConstantExprUnevaluated(Cond, New, Diags)) {
209  S.Diag(A->getLocation(), diag::err_attr_cond_never_constant_expr) << A;
210  for (const auto &P : Diags)
211  S.Diag(P.first, P.second);
212  return nullptr;
213  }
214  return Cond;
215 }
216 
218  Sema &S, const MultiLevelTemplateArgumentList &TemplateArgs,
219  const EnableIfAttr *EIA, const Decl *Tmpl, FunctionDecl *New) {
221  S, TemplateArgs, EIA, EIA->getCond(), Tmpl, New);
222 
223  if (Cond)
224  New->addAttr(new (S.getASTContext()) EnableIfAttr(
225  EIA->getLocation(), S.getASTContext(), Cond, EIA->getMessage(),
226  EIA->getSpellingListIndex()));
227 }
228 
230  Sema &S, const MultiLevelTemplateArgumentList &TemplateArgs,
231  const DiagnoseIfAttr *DIA, const Decl *Tmpl, FunctionDecl *New) {
233  S, TemplateArgs, DIA, DIA->getCond(), Tmpl, New);
234 
235  if (Cond)
236  New->addAttr(new (S.getASTContext()) DiagnoseIfAttr(
237  DIA->getLocation(), S.getASTContext(), Cond, DIA->getMessage(),
238  DIA->getDiagnosticType(), DIA->getArgDependent(), New,
239  DIA->getSpellingListIndex()));
240 }
241 
242 // Constructs and adds to New a new instance of CUDALaunchBoundsAttr using
243 // template A as the base and arguments from TemplateArgs.
245  Sema &S, const MultiLevelTemplateArgumentList &TemplateArgs,
246  const CUDALaunchBoundsAttr &Attr, Decl *New) {
247  // The alignment expression is a constant expression.
250 
251  ExprResult Result = S.SubstExpr(Attr.getMaxThreads(), TemplateArgs);
252  if (Result.isInvalid())
253  return;
254  Expr *MaxThreads = Result.getAs<Expr>();
255 
256  Expr *MinBlocks = nullptr;
257  if (Attr.getMinBlocks()) {
258  Result = S.SubstExpr(Attr.getMinBlocks(), TemplateArgs);
259  if (Result.isInvalid())
260  return;
261  MinBlocks = Result.getAs<Expr>();
262  }
263 
264  S.AddLaunchBoundsAttr(Attr.getLocation(), New, MaxThreads, MinBlocks,
265  Attr.getSpellingListIndex());
266 }
267 
268 static void
270  const MultiLevelTemplateArgumentList &TemplateArgs,
271  const ModeAttr &Attr, Decl *New) {
272  S.AddModeAttr(Attr.getRange(), New, Attr.getMode(),
273  Attr.getSpellingListIndex(), /*InInstantiation=*/true);
274 }
275 
276 /// Instantiation of 'declare simd' attribute and its arguments.
278  Sema &S, const MultiLevelTemplateArgumentList &TemplateArgs,
279  const OMPDeclareSimdDeclAttr &Attr, Decl *New) {
280  // Allow 'this' in clauses with varlists.
281  if (auto *FTD = dyn_cast<FunctionTemplateDecl>(New))
282  New = FTD->getTemplatedDecl();
283  auto *FD = cast<FunctionDecl>(New);
284  auto *ThisContext = dyn_cast_or_null<CXXRecordDecl>(FD->getDeclContext());
285  SmallVector<Expr *, 4> Uniforms, Aligneds, Alignments, Linears, Steps;
286  SmallVector<unsigned, 4> LinModifiers;
287 
288  auto &&Subst = [&](Expr *E) -> ExprResult {
289  if (auto *DRE = dyn_cast<DeclRefExpr>(E->IgnoreParenImpCasts()))
290  if (auto *PVD = dyn_cast<ParmVarDecl>(DRE->getDecl())) {
291  Sema::ContextRAII SavedContext(S, FD);
292  LocalInstantiationScope Local(S);
293  if (FD->getNumParams() > PVD->getFunctionScopeIndex())
294  Local.InstantiatedLocal(
295  PVD, FD->getParamDecl(PVD->getFunctionScopeIndex()));
296  return S.SubstExpr(E, TemplateArgs);
297  }
298  Sema::CXXThisScopeRAII ThisScope(S, ThisContext, /*TypeQuals=*/0,
299  FD->isCXXInstanceMember());
300  return S.SubstExpr(E, TemplateArgs);
301  };
302 
303  ExprResult Simdlen;
304  if (auto *E = Attr.getSimdlen())
305  Simdlen = Subst(E);
306 
307  if (Attr.uniforms_size() > 0) {
308  for(auto *E : Attr.uniforms()) {
309  ExprResult Inst = Subst(E);
310  if (Inst.isInvalid())
311  continue;
312  Uniforms.push_back(Inst.get());
313  }
314  }
315 
316  auto AI = Attr.alignments_begin();
317  for (auto *E : Attr.aligneds()) {
318  ExprResult Inst = Subst(E);
319  if (Inst.isInvalid())
320  continue;
321  Aligneds.push_back(Inst.get());
322  Inst = ExprEmpty();
323  if (*AI)
324  Inst = S.SubstExpr(*AI, TemplateArgs);
325  Alignments.push_back(Inst.get());
326  ++AI;
327  }
328 
329  auto SI = Attr.steps_begin();
330  for (auto *E : Attr.linears()) {
331  ExprResult Inst = Subst(E);
332  if (Inst.isInvalid())
333  continue;
334  Linears.push_back(Inst.get());
335  Inst = ExprEmpty();
336  if (*SI)
337  Inst = S.SubstExpr(*SI, TemplateArgs);
338  Steps.push_back(Inst.get());
339  ++SI;
340  }
341  LinModifiers.append(Attr.modifiers_begin(), Attr.modifiers_end());
343  S.ConvertDeclToDeclGroup(New), Attr.getBranchState(), Simdlen.get(),
344  Uniforms, Aligneds, Alignments, Linears, LinModifiers, Steps,
345  Attr.getRange());
346 }
347 
349  const MultiLevelTemplateArgumentList &TemplateArgs, const Decl *Tmpl,
350  Decl *New, LateInstantiatedAttrVec *LateAttrs,
351  LocalInstantiationScope *OuterMostScope) {
352  if (NamedDecl *ND = dyn_cast<NamedDecl>(New)) {
353  for (const auto *TmplAttr : Tmpl->attrs()) {
354  // FIXME: If any of the special case versions from InstantiateAttrs become
355  // applicable to template declaration, we'll need to add them here.
356  CXXThisScopeRAII ThisScope(
357  *this, dyn_cast_or_null<CXXRecordDecl>(ND->getDeclContext()),
358  /*TypeQuals*/ 0, ND->isCXXInstanceMember());
359 
361  TmplAttr, Context, *this, TemplateArgs);
362  if (NewAttr)
363  New->addAttr(NewAttr);
364  }
365  }
366 }
367 
369  const Decl *Tmpl, Decl *New,
370  LateInstantiatedAttrVec *LateAttrs,
371  LocalInstantiationScope *OuterMostScope) {
372  for (const auto *TmplAttr : Tmpl->attrs()) {
373  // FIXME: This should be generalized to more than just the AlignedAttr.
374  const AlignedAttr *Aligned = dyn_cast<AlignedAttr>(TmplAttr);
375  if (Aligned && Aligned->isAlignmentDependent()) {
376  instantiateDependentAlignedAttr(*this, TemplateArgs, Aligned, New);
377  continue;
378  }
379 
380  const AssumeAlignedAttr *AssumeAligned = dyn_cast<AssumeAlignedAttr>(TmplAttr);
381  if (AssumeAligned) {
382  instantiateDependentAssumeAlignedAttr(*this, TemplateArgs, AssumeAligned, New);
383  continue;
384  }
385 
386  const AlignValueAttr *AlignValue = dyn_cast<AlignValueAttr>(TmplAttr);
387  if (AlignValue) {
388  instantiateDependentAlignValueAttr(*this, TemplateArgs, AlignValue, New);
389  continue;
390  }
391 
392  if (const auto *AllocAlign = dyn_cast<AllocAlignAttr>(TmplAttr)) {
393  instantiateDependentAllocAlignAttr(*this, TemplateArgs, AllocAlign, New);
394  continue;
395  }
396 
397 
398  if (const auto *EnableIf = dyn_cast<EnableIfAttr>(TmplAttr)) {
399  instantiateDependentEnableIfAttr(*this, TemplateArgs, EnableIf, Tmpl,
400  cast<FunctionDecl>(New));
401  continue;
402  }
403 
404  if (const auto *DiagnoseIf = dyn_cast<DiagnoseIfAttr>(TmplAttr)) {
405  instantiateDependentDiagnoseIfAttr(*this, TemplateArgs, DiagnoseIf, Tmpl,
406  cast<FunctionDecl>(New));
407  continue;
408  }
409 
410  if (const CUDALaunchBoundsAttr *CUDALaunchBounds =
411  dyn_cast<CUDALaunchBoundsAttr>(TmplAttr)) {
412  instantiateDependentCUDALaunchBoundsAttr(*this, TemplateArgs,
413  *CUDALaunchBounds, New);
414  continue;
415  }
416 
417  if (const ModeAttr *Mode = dyn_cast<ModeAttr>(TmplAttr)) {
418  instantiateDependentModeAttr(*this, TemplateArgs, *Mode, New);
419  continue;
420  }
421 
422  if (const auto *OMPAttr = dyn_cast<OMPDeclareSimdDeclAttr>(TmplAttr)) {
423  instantiateOMPDeclareSimdDeclAttr(*this, TemplateArgs, *OMPAttr, New);
424  continue;
425  }
426 
427  // Existing DLL attribute on the instantiation takes precedence.
428  if (TmplAttr->getKind() == attr::DLLExport ||
429  TmplAttr->getKind() == attr::DLLImport) {
430  if (New->hasAttr<DLLExportAttr>() || New->hasAttr<DLLImportAttr>()) {
431  continue;
432  }
433  }
434 
435  if (auto ABIAttr = dyn_cast<ParameterABIAttr>(TmplAttr)) {
436  AddParameterABIAttr(ABIAttr->getRange(), New, ABIAttr->getABI(),
437  ABIAttr->getSpellingListIndex());
438  continue;
439  }
440 
441  if (isa<NSConsumedAttr>(TmplAttr) || isa<CFConsumedAttr>(TmplAttr)) {
442  AddNSConsumedAttr(TmplAttr->getRange(), New,
443  TmplAttr->getSpellingListIndex(),
444  isa<NSConsumedAttr>(TmplAttr),
445  /*template instantiation*/ true);
446  continue;
447  }
448 
449  assert(!TmplAttr->isPackExpansion());
450  if (TmplAttr->isLateParsed() && LateAttrs) {
451  // Late parsed attributes must be instantiated and attached after the
452  // enclosing class has been instantiated. See Sema::InstantiateClass.
453  LocalInstantiationScope *Saved = nullptr;
454  if (CurrentInstantiationScope)
455  Saved = CurrentInstantiationScope->cloneScopes(OuterMostScope);
456  LateAttrs->push_back(LateInstantiatedAttribute(TmplAttr, Saved, New));
457  } else {
458  // Allow 'this' within late-parsed attributes.
459  NamedDecl *ND = dyn_cast<NamedDecl>(New);
460  CXXRecordDecl *ThisContext =
461  dyn_cast_or_null<CXXRecordDecl>(ND->getDeclContext());
462  CXXThisScopeRAII ThisScope(*this, ThisContext, /*TypeQuals*/0,
463  ND && ND->isCXXInstanceMember());
464 
465  Attr *NewAttr = sema::instantiateTemplateAttribute(TmplAttr, Context,
466  *this, TemplateArgs);
467  if (NewAttr)
468  New->addAttr(NewAttr);
469  }
470  }
471 }
472 
473 /// Get the previous declaration of a declaration for the purposes of template
474 /// instantiation. If this finds a previous declaration, then the previous
475 /// declaration of the instantiation of D should be an instantiation of the
476 /// result of this function.
477 template<typename DeclT>
478 static DeclT *getPreviousDeclForInstantiation(DeclT *D) {
479  DeclT *Result = D->getPreviousDecl();
480 
481  // If the declaration is within a class, and the previous declaration was
482  // merged from a different definition of that class, then we don't have a
483  // previous declaration for the purpose of template instantiation.
484  if (Result && isa<CXXRecordDecl>(D->getDeclContext()) &&
485  D->getLexicalDeclContext() != Result->getLexicalDeclContext())
486  return nullptr;
487 
488  return Result;
489 }
490 
491 Decl *
492 TemplateDeclInstantiator::VisitTranslationUnitDecl(TranslationUnitDecl *D) {
493  llvm_unreachable("Translation units cannot be instantiated");
494 }
495 
496 Decl *
497 TemplateDeclInstantiator::VisitPragmaCommentDecl(PragmaCommentDecl *D) {
498  llvm_unreachable("pragma comment cannot be instantiated");
499 }
500 
501 Decl *TemplateDeclInstantiator::VisitPragmaDetectMismatchDecl(
503  llvm_unreachable("pragma comment cannot be instantiated");
504 }
505 
506 Decl *
507 TemplateDeclInstantiator::VisitExternCContextDecl(ExternCContextDecl *D) {
508  llvm_unreachable("extern \"C\" context cannot be instantiated");
509 }
510 
511 Decl *
512 TemplateDeclInstantiator::VisitLabelDecl(LabelDecl *D) {
513  LabelDecl *Inst = LabelDecl::Create(SemaRef.Context, Owner, D->getLocation(),
514  D->getIdentifier());
515  Owner->addDecl(Inst);
516  return Inst;
517 }
518 
519 Decl *
520 TemplateDeclInstantiator::VisitNamespaceDecl(NamespaceDecl *D) {
521  llvm_unreachable("Namespaces cannot be instantiated");
522 }
523 
524 Decl *
525 TemplateDeclInstantiator::VisitNamespaceAliasDecl(NamespaceAliasDecl *D) {
526  NamespaceAliasDecl *Inst
527  = NamespaceAliasDecl::Create(SemaRef.Context, Owner,
528  D->getNamespaceLoc(),
529  D->getAliasLoc(),
530  D->getIdentifier(),
531  D->getQualifierLoc(),
532  D->getTargetNameLoc(),
533  D->getNamespace());
534  Owner->addDecl(Inst);
535  return Inst;
536 }
537 
539  bool IsTypeAlias) {
540  bool Invalid = false;
542  if (DI->getType()->isInstantiationDependentType() ||
543  DI->getType()->isVariablyModifiedType()) {
544  DI = SemaRef.SubstType(DI, TemplateArgs,
545  D->getLocation(), D->getDeclName());
546  if (!DI) {
547  Invalid = true;
548  DI = SemaRef.Context.getTrivialTypeSourceInfo(SemaRef.Context.IntTy);
549  }
550  } else {
552  }
553 
554  // HACK: g++ has a bug where it gets the value kind of ?: wrong.
555  // libstdc++ relies upon this bug in its implementation of common_type.
556  // If we happen to be processing that implementation, fake up the g++ ?:
557  // semantics. See LWG issue 2141 for more information on the bug.
558  const DecltypeType *DT = DI->getType()->getAs<DecltypeType>();
559  CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(D->getDeclContext());
560  if (DT && RD && isa<ConditionalOperator>(DT->getUnderlyingExpr()) &&
561  DT->isReferenceType() &&
562  RD->getEnclosingNamespaceContext() == SemaRef.getStdNamespace() &&
563  RD->getIdentifier() && RD->getIdentifier()->isStr("common_type") &&
564  D->getIdentifier() && D->getIdentifier()->isStr("type") &&
566  // Fold it to the (non-reference) type which g++ would have produced.
567  DI = SemaRef.Context.getTrivialTypeSourceInfo(
568  DI->getType().getNonReferenceType());
569 
570  // Create the new typedef
571  TypedefNameDecl *Typedef;
572  if (IsTypeAlias)
573  Typedef = TypeAliasDecl::Create(SemaRef.Context, Owner, D->getLocStart(),
574  D->getLocation(), D->getIdentifier(), DI);
575  else
576  Typedef = TypedefDecl::Create(SemaRef.Context, Owner, D->getLocStart(),
577  D->getLocation(), D->getIdentifier(), DI);
578  if (Invalid)
579  Typedef->setInvalidDecl();
580 
581  // If the old typedef was the name for linkage purposes of an anonymous
582  // tag decl, re-establish that relationship for the new typedef.
583  if (const TagType *oldTagType = D->getUnderlyingType()->getAs<TagType>()) {
584  TagDecl *oldTag = oldTagType->getDecl();
585  if (oldTag->getTypedefNameForAnonDecl() == D && !Invalid) {
586  TagDecl *newTag = DI->getType()->castAs<TagType>()->getDecl();
587  assert(!newTag->hasNameForLinkage());
588  newTag->setTypedefNameForAnonDecl(Typedef);
589  }
590  }
591 
593  NamedDecl *InstPrev = SemaRef.FindInstantiatedDecl(D->getLocation(), Prev,
594  TemplateArgs);
595  if (!InstPrev)
596  return nullptr;
597 
598  TypedefNameDecl *InstPrevTypedef = cast<TypedefNameDecl>(InstPrev);
599 
600  // If the typedef types are not identical, reject them.
601  SemaRef.isIncompatibleTypedef(InstPrevTypedef, Typedef);
602 
603  Typedef->setPreviousDecl(InstPrevTypedef);
604  }
605 
606  SemaRef.InstantiateAttrs(TemplateArgs, D, Typedef);
607 
608  Typedef->setAccess(D->getAccess());
609 
610  return Typedef;
611 }
612 
613 Decl *TemplateDeclInstantiator::VisitTypedefDecl(TypedefDecl *D) {
614  Decl *Typedef = InstantiateTypedefNameDecl(D, /*IsTypeAlias=*/false);
615  if (Typedef)
616  Owner->addDecl(Typedef);
617  return Typedef;
618 }
619 
620 Decl *TemplateDeclInstantiator::VisitTypeAliasDecl(TypeAliasDecl *D) {
621  Decl *Typedef = InstantiateTypedefNameDecl(D, /*IsTypeAlias=*/true);
622  if (Typedef)
623  Owner->addDecl(Typedef);
624  return Typedef;
625 }
626 
627 Decl *
628 TemplateDeclInstantiator::VisitTypeAliasTemplateDecl(TypeAliasTemplateDecl *D) {
629  // Create a local instantiation scope for this type alias template, which
630  // will contain the instantiations of the template parameters.
632 
633  TemplateParameterList *TempParams = D->getTemplateParameters();
634  TemplateParameterList *InstParams = SubstTemplateParams(TempParams);
635  if (!InstParams)
636  return nullptr;
637 
638  TypeAliasDecl *Pattern = D->getTemplatedDecl();
639 
640  TypeAliasTemplateDecl *PrevAliasTemplate = nullptr;
641  if (getPreviousDeclForInstantiation<TypedefNameDecl>(Pattern)) {
642  DeclContext::lookup_result Found = Owner->lookup(Pattern->getDeclName());
643  if (!Found.empty()) {
644  PrevAliasTemplate = dyn_cast<TypeAliasTemplateDecl>(Found.front());
645  }
646  }
647 
648  TypeAliasDecl *AliasInst = cast_or_null<TypeAliasDecl>(
649  InstantiateTypedefNameDecl(Pattern, /*IsTypeAlias=*/true));
650  if (!AliasInst)
651  return nullptr;
652 
654  = TypeAliasTemplateDecl::Create(SemaRef.Context, Owner, D->getLocation(),
655  D->getDeclName(), InstParams, AliasInst);
656  AliasInst->setDescribedAliasTemplate(Inst);
657  if (PrevAliasTemplate)
658  Inst->setPreviousDecl(PrevAliasTemplate);
659 
660  Inst->setAccess(D->getAccess());
661 
662  if (!PrevAliasTemplate)
664 
665  Owner->addDecl(Inst);
666 
667  return Inst;
668 }
669 
670 Decl *TemplateDeclInstantiator::VisitBindingDecl(BindingDecl *D) {
671  auto *NewBD = BindingDecl::Create(SemaRef.Context, Owner, D->getLocation(),
672  D->getIdentifier());
673  NewBD->setReferenced(D->isReferenced());
674  SemaRef.CurrentInstantiationScope->InstantiatedLocal(D, NewBD);
675  return NewBD;
676 }
677 
678 Decl *TemplateDeclInstantiator::VisitDecompositionDecl(DecompositionDecl *D) {
679  // Transform the bindings first.
680  SmallVector<BindingDecl*, 16> NewBindings;
681  for (auto *OldBD : D->bindings())
682  NewBindings.push_back(cast<BindingDecl>(VisitBindingDecl(OldBD)));
683  ArrayRef<BindingDecl*> NewBindingArray = NewBindings;
684 
685  auto *NewDD = cast_or_null<DecompositionDecl>(
686  VisitVarDecl(D, /*InstantiatingVarTemplate=*/false, &NewBindingArray));
687 
688  if (!NewDD || NewDD->isInvalidDecl())
689  for (auto *NewBD : NewBindings)
690  NewBD->setInvalidDecl();
691 
692  return NewDD;
693 }
694 
696  return VisitVarDecl(D, /*InstantiatingVarTemplate=*/false);
697 }
698 
700  bool InstantiatingVarTemplate,
701  ArrayRef<BindingDecl*> *Bindings) {
702 
703  // Do substitution on the type of the declaration
704  TypeSourceInfo *DI = SemaRef.SubstType(
705  D->getTypeSourceInfo(), TemplateArgs, D->getTypeSpecStartLoc(),
706  D->getDeclName(), /*AllowDeducedTST*/true);
707  if (!DI)
708  return nullptr;
709 
710  if (DI->getType()->isFunctionType()) {
711  SemaRef.Diag(D->getLocation(), diag::err_variable_instantiates_to_function)
712  << D->isStaticDataMember() << DI->getType();
713  return nullptr;
714  }
715 
716  DeclContext *DC = Owner;
717  if (D->isLocalExternDecl())
719 
720  // Build the instantiated declaration.
721  VarDecl *Var;
722  if (Bindings)
723  Var = DecompositionDecl::Create(SemaRef.Context, DC, D->getInnerLocStart(),
724  D->getLocation(), DI->getType(), DI,
725  D->getStorageClass(), *Bindings);
726  else
727  Var = VarDecl::Create(SemaRef.Context, DC, D->getInnerLocStart(),
728  D->getLocation(), D->getIdentifier(), DI->getType(),
729  DI, D->getStorageClass());
730 
731  // In ARC, infer 'retaining' for variables of retainable type.
732  if (SemaRef.getLangOpts().ObjCAutoRefCount &&
733  SemaRef.inferObjCARCLifetime(Var))
734  Var->setInvalidDecl();
735 
736  // Substitute the nested name specifier, if any.
737  if (SubstQualifier(D, Var))
738  return nullptr;
739 
740  SemaRef.BuildVariableInstantiation(Var, D, TemplateArgs, LateAttrs, Owner,
741  StartingScope, InstantiatingVarTemplate);
742 
743  if (D->isNRVOVariable()) {
744  QualType ReturnType = cast<FunctionDecl>(DC)->getReturnType();
745  if (SemaRef.isCopyElisionCandidate(ReturnType, Var, Sema::CES_Strict))
746  Var->setNRVOVariable(true);
747  }
748 
749  Var->setImplicit(D->isImplicit());
750 
751  return Var;
752 }
753 
754 Decl *TemplateDeclInstantiator::VisitAccessSpecDecl(AccessSpecDecl *D) {
755  AccessSpecDecl* AD
756  = AccessSpecDecl::Create(SemaRef.Context, D->getAccess(), Owner,
758  Owner->addHiddenDecl(AD);
759  return AD;
760 }
761 
762 Decl *TemplateDeclInstantiator::VisitFieldDecl(FieldDecl *D) {
763  bool Invalid = false;
765  if (DI->getType()->isInstantiationDependentType() ||
766  DI->getType()->isVariablyModifiedType()) {
767  DI = SemaRef.SubstType(DI, TemplateArgs,
768  D->getLocation(), D->getDeclName());
769  if (!DI) {
770  DI = D->getTypeSourceInfo();
771  Invalid = true;
772  } else if (DI->getType()->isFunctionType()) {
773  // C++ [temp.arg.type]p3:
774  // If a declaration acquires a function type through a type
775  // dependent on a template-parameter and this causes a
776  // declaration that does not use the syntactic form of a
777  // function declarator to have function type, the program is
778  // ill-formed.
779  SemaRef.Diag(D->getLocation(), diag::err_field_instantiates_to_function)
780  << DI->getType();
781  Invalid = true;
782  }
783  } else {
785  }
786 
787  Expr *BitWidth = D->getBitWidth();
788  if (Invalid)
789  BitWidth = nullptr;
790  else if (BitWidth) {
791  // The bit-width expression is a constant expression.
794 
795  ExprResult InstantiatedBitWidth
796  = SemaRef.SubstExpr(BitWidth, TemplateArgs);
797  if (InstantiatedBitWidth.isInvalid()) {
798  Invalid = true;
799  BitWidth = nullptr;
800  } else
801  BitWidth = InstantiatedBitWidth.getAs<Expr>();
802  }
803 
804  FieldDecl *Field = SemaRef.CheckFieldDecl(D->getDeclName(),
805  DI->getType(), DI,
806  cast<RecordDecl>(Owner),
807  D->getLocation(),
808  D->isMutable(),
809  BitWidth,
810  D->getInClassInitStyle(),
811  D->getInnerLocStart(),
812  D->getAccess(),
813  nullptr);
814  if (!Field) {
815  cast<Decl>(Owner)->setInvalidDecl();
816  return nullptr;
817  }
818 
819  SemaRef.InstantiateAttrs(TemplateArgs, D, Field, LateAttrs, StartingScope);
820 
821  if (Field->hasAttrs())
822  SemaRef.CheckAlignasUnderalignment(Field);
823 
824  if (Invalid)
825  Field->setInvalidDecl();
826 
827  if (!Field->getDeclName()) {
828  // Keep track of where this decl came from.
830  }
831  if (CXXRecordDecl *Parent= dyn_cast<CXXRecordDecl>(Field->getDeclContext())) {
832  if (Parent->isAnonymousStructOrUnion() &&
833  Parent->getRedeclContext()->isFunctionOrMethod())
834  SemaRef.CurrentInstantiationScope->InstantiatedLocal(D, Field);
835  }
836 
837  Field->setImplicit(D->isImplicit());
838  Field->setAccess(D->getAccess());
839  Owner->addDecl(Field);
840 
841  return Field;
842 }
843 
844 Decl *TemplateDeclInstantiator::VisitMSPropertyDecl(MSPropertyDecl *D) {
845  bool Invalid = false;
847 
848  if (DI->getType()->isVariablyModifiedType()) {
849  SemaRef.Diag(D->getLocation(), diag::err_property_is_variably_modified)
850  << D;
851  Invalid = true;
852  } else if (DI->getType()->isInstantiationDependentType()) {
853  DI = SemaRef.SubstType(DI, TemplateArgs,
854  D->getLocation(), D->getDeclName());
855  if (!DI) {
856  DI = D->getTypeSourceInfo();
857  Invalid = true;
858  } else if (DI->getType()->isFunctionType()) {
859  // C++ [temp.arg.type]p3:
860  // If a declaration acquires a function type through a type
861  // dependent on a template-parameter and this causes a
862  // declaration that does not use the syntactic form of a
863  // function declarator to have function type, the program is
864  // ill-formed.
865  SemaRef.Diag(D->getLocation(), diag::err_field_instantiates_to_function)
866  << DI->getType();
867  Invalid = true;
868  }
869  } else {
871  }
872 
874  SemaRef.Context, Owner, D->getLocation(), D->getDeclName(), DI->getType(),
875  DI, D->getLocStart(), D->getGetterId(), D->getSetterId());
876 
877  SemaRef.InstantiateAttrs(TemplateArgs, D, Property, LateAttrs,
878  StartingScope);
879 
880  if (Invalid)
881  Property->setInvalidDecl();
882 
883  Property->setAccess(D->getAccess());
884  Owner->addDecl(Property);
885 
886  return Property;
887 }
888 
889 Decl *TemplateDeclInstantiator::VisitIndirectFieldDecl(IndirectFieldDecl *D) {
890  NamedDecl **NamedChain =
891  new (SemaRef.Context)NamedDecl*[D->getChainingSize()];
892 
893  int i = 0;
894  for (auto *PI : D->chain()) {
895  NamedDecl *Next = SemaRef.FindInstantiatedDecl(D->getLocation(), PI,
896  TemplateArgs);
897  if (!Next)
898  return nullptr;
899 
900  NamedChain[i++] = Next;
901  }
902 
903  QualType T = cast<FieldDecl>(NamedChain[i-1])->getType();
905  SemaRef.Context, Owner, D->getLocation(), D->getIdentifier(), T,
906  {NamedChain, D->getChainingSize()});
907 
908  for (const auto *Attr : D->attrs())
909  IndirectField->addAttr(Attr->clone(SemaRef.Context));
910 
911  IndirectField->setImplicit(D->isImplicit());
912  IndirectField->setAccess(D->getAccess());
913  Owner->addDecl(IndirectField);
914  return IndirectField;
915 }
916 
917 Decl *TemplateDeclInstantiator::VisitFriendDecl(FriendDecl *D) {
918  // Handle friend type expressions by simply substituting template
919  // parameters into the pattern type and checking the result.
920  if (TypeSourceInfo *Ty = D->getFriendType()) {
921  TypeSourceInfo *InstTy;
922  // If this is an unsupported friend, don't bother substituting template
923  // arguments into it. The actual type referred to won't be used by any
924  // parts of Clang, and may not be valid for instantiating. Just use the
925  // same info for the instantiated friend.
926  if (D->isUnsupportedFriend()) {
927  InstTy = Ty;
928  } else {
929  InstTy = SemaRef.SubstType(Ty, TemplateArgs,
930  D->getLocation(), DeclarationName());
931  }
932  if (!InstTy)
933  return nullptr;
934 
935  FriendDecl *FD = SemaRef.CheckFriendTypeDecl(D->getLocStart(),
936  D->getFriendLoc(), InstTy);
937  if (!FD)
938  return nullptr;
939 
940  FD->setAccess(AS_public);
942  Owner->addDecl(FD);
943  return FD;
944  }
945 
946  NamedDecl *ND = D->getFriendDecl();
947  assert(ND && "friend decl must be a decl or a type!");
948 
949  // All of the Visit implementations for the various potential friend
950  // declarations have to be carefully written to work for friend
951  // objects, with the most important detail being that the target
952  // decl should almost certainly not be placed in Owner.
953  Decl *NewND = Visit(ND);
954  if (!NewND) return nullptr;
955 
956  FriendDecl *FD =
957  FriendDecl::Create(SemaRef.Context, Owner, D->getLocation(),
958  cast<NamedDecl>(NewND), D->getFriendLoc());
959  FD->setAccess(AS_public);
961  Owner->addDecl(FD);
962  return FD;
963 }
964 
965 Decl *TemplateDeclInstantiator::VisitStaticAssertDecl(StaticAssertDecl *D) {
966  Expr *AssertExpr = D->getAssertExpr();
967 
968  // The expression in a static assertion is a constant expression.
971 
972  ExprResult InstantiatedAssertExpr
973  = SemaRef.SubstExpr(AssertExpr, TemplateArgs);
974  if (InstantiatedAssertExpr.isInvalid())
975  return nullptr;
976 
977  return SemaRef.BuildStaticAssertDeclaration(D->getLocation(),
978  InstantiatedAssertExpr.get(),
979  D->getMessage(),
980  D->getRParenLoc(),
981  D->isFailed());
982 }
983 
984 Decl *TemplateDeclInstantiator::VisitEnumDecl(EnumDecl *D) {
985  EnumDecl *PrevDecl = nullptr;
986  if (EnumDecl *PatternPrev = getPreviousDeclForInstantiation(D)) {
987  NamedDecl *Prev = SemaRef.FindInstantiatedDecl(D->getLocation(),
988  PatternPrev,
989  TemplateArgs);
990  if (!Prev) return nullptr;
991  PrevDecl = cast<EnumDecl>(Prev);
992  }
993 
994  EnumDecl *Enum = EnumDecl::Create(SemaRef.Context, Owner, D->getLocStart(),
995  D->getLocation(), D->getIdentifier(),
996  PrevDecl, D->isScoped(),
997  D->isScopedUsingClassTag(), D->isFixed());
998  if (D->isFixed()) {
999  if (TypeSourceInfo *TI = D->getIntegerTypeSourceInfo()) {
1000  // If we have type source information for the underlying type, it means it
1001  // has been explicitly set by the user. Perform substitution on it before
1002  // moving on.
1003  SourceLocation UnderlyingLoc = TI->getTypeLoc().getBeginLoc();
1004  TypeSourceInfo *NewTI = SemaRef.SubstType(TI, TemplateArgs, UnderlyingLoc,
1005  DeclarationName());
1006  if (!NewTI || SemaRef.CheckEnumUnderlyingType(NewTI))
1007  Enum->setIntegerType(SemaRef.Context.IntTy);
1008  else
1009  Enum->setIntegerTypeSourceInfo(NewTI);
1010  } else {
1011  assert(!D->getIntegerType()->isDependentType()
1012  && "Dependent type without type source info");
1013  Enum->setIntegerType(D->getIntegerType());
1014  }
1015  }
1016 
1017  SemaRef.InstantiateAttrs(TemplateArgs, D, Enum);
1018 
1019  Enum->setInstantiationOfMemberEnum(D, TSK_ImplicitInstantiation);
1020  Enum->setAccess(D->getAccess());
1021  // Forward the mangling number from the template to the instantiated decl.
1022  SemaRef.Context.setManglingNumber(Enum, SemaRef.Context.getManglingNumber(D));
1023  // See if the old tag was defined along with a declarator.
1024  // If it did, mark the new tag as being associated with that declarator.
1026  SemaRef.Context.addDeclaratorForUnnamedTagDecl(Enum, DD);
1027  // See if the old tag was defined along with a typedef.
1028  // If it did, mark the new tag as being associated with that typedef.
1030  SemaRef.Context.addTypedefNameForUnnamedTagDecl(Enum, TND);
1031  if (SubstQualifier(D, Enum)) return nullptr;
1032  Owner->addDecl(Enum);
1033 
1034  EnumDecl *Def = D->getDefinition();
1035  if (Def && Def != D) {
1036  // If this is an out-of-line definition of an enum member template, check
1037  // that the underlying types match in the instantiation of both
1038  // declarations.
1039  if (TypeSourceInfo *TI = Def->getIntegerTypeSourceInfo()) {
1040  SourceLocation UnderlyingLoc = TI->getTypeLoc().getBeginLoc();
1041  QualType DefnUnderlying =
1042  SemaRef.SubstType(TI->getType(), TemplateArgs,
1043  UnderlyingLoc, DeclarationName());
1044  SemaRef.CheckEnumRedeclaration(Def->getLocation(), Def->isScoped(),
1045  DefnUnderlying, /*IsFixed=*/true, Enum);
1046  }
1047  }
1048 
1049  // C++11 [temp.inst]p1: The implicit instantiation of a class template
1050  // specialization causes the implicit instantiation of the declarations, but
1051  // not the definitions of scoped member enumerations.
1052  //
1053  // DR1484 clarifies that enumeration definitions inside of a template
1054  // declaration aren't considered entities that can be separately instantiated
1055  // from the rest of the entity they are declared inside of.
1056  if (isDeclWithinFunction(D) ? D == Def : Def && !Enum->isScoped()) {
1057  SemaRef.CurrentInstantiationScope->InstantiatedLocal(D, Enum);
1058  InstantiateEnumDefinition(Enum, Def);
1059  }
1060 
1061  return Enum;
1062 }
1063 
1065  EnumDecl *Enum, EnumDecl *Pattern) {
1066  Enum->startDefinition();
1067 
1068  // Update the location to refer to the definition.
1069  Enum->setLocation(Pattern->getLocation());
1070 
1071  SmallVector<Decl*, 4> Enumerators;
1072 
1073  EnumConstantDecl *LastEnumConst = nullptr;
1074  for (auto *EC : Pattern->enumerators()) {
1075  // The specified value for the enumerator.
1076  ExprResult Value((Expr *)nullptr);
1077  if (Expr *UninstValue = EC->getInitExpr()) {
1078  // The enumerator's value expression is a constant expression.
1081 
1082  Value = SemaRef.SubstExpr(UninstValue, TemplateArgs);
1083  }
1084 
1085  // Drop the initial value and continue.
1086  bool isInvalid = false;
1087  if (Value.isInvalid()) {
1088  Value = nullptr;
1089  isInvalid = true;
1090  }
1091 
1092  EnumConstantDecl *EnumConst
1093  = SemaRef.CheckEnumConstant(Enum, LastEnumConst,
1094  EC->getLocation(), EC->getIdentifier(),
1095  Value.get());
1096 
1097  if (isInvalid) {
1098  if (EnumConst)
1099  EnumConst->setInvalidDecl();
1100  Enum->setInvalidDecl();
1101  }
1102 
1103  if (EnumConst) {
1104  SemaRef.InstantiateAttrs(TemplateArgs, EC, EnumConst);
1105 
1106  EnumConst->setAccess(Enum->getAccess());
1107  Enum->addDecl(EnumConst);
1108  Enumerators.push_back(EnumConst);
1109  LastEnumConst = EnumConst;
1110 
1111  if (Pattern->getDeclContext()->isFunctionOrMethod() &&
1112  !Enum->isScoped()) {
1113  // If the enumeration is within a function or method, record the enum
1114  // constant as a local.
1115  SemaRef.CurrentInstantiationScope->InstantiatedLocal(EC, EnumConst);
1116  }
1117  }
1118  }
1119 
1120  SemaRef.ActOnEnumBody(Enum->getLocation(), Enum->getBraceRange(), Enum,
1121  Enumerators,
1122  nullptr, nullptr);
1123 }
1124 
1125 Decl *TemplateDeclInstantiator::VisitEnumConstantDecl(EnumConstantDecl *D) {
1126  llvm_unreachable("EnumConstantDecls can only occur within EnumDecls.");
1127 }
1128 
1129 Decl *
1130 TemplateDeclInstantiator::VisitBuiltinTemplateDecl(BuiltinTemplateDecl *D) {
1131  llvm_unreachable("BuiltinTemplateDecls cannot be instantiated.");
1132 }
1133 
1134 Decl *TemplateDeclInstantiator::VisitClassTemplateDecl(ClassTemplateDecl *D) {
1135  bool isFriend = (D->getFriendObjectKind() != Decl::FOK_None);
1136 
1137  // Create a local instantiation scope for this class template, which
1138  // will contain the instantiations of the template parameters.
1139  LocalInstantiationScope Scope(SemaRef);
1140  TemplateParameterList *TempParams = D->getTemplateParameters();
1141  TemplateParameterList *InstParams = SubstTemplateParams(TempParams);
1142  if (!InstParams)
1143  return nullptr;
1144 
1145  CXXRecordDecl *Pattern = D->getTemplatedDecl();
1146 
1147  // Instantiate the qualifier. We have to do this first in case
1148  // we're a friend declaration, because if we are then we need to put
1149  // the new declaration in the appropriate context.
1150  NestedNameSpecifierLoc QualifierLoc = Pattern->getQualifierLoc();
1151  if (QualifierLoc) {
1152  QualifierLoc = SemaRef.SubstNestedNameSpecifierLoc(QualifierLoc,
1153  TemplateArgs);
1154  if (!QualifierLoc)
1155  return nullptr;
1156  }
1157 
1158  CXXRecordDecl *PrevDecl = nullptr;
1159  ClassTemplateDecl *PrevClassTemplate = nullptr;
1160 
1161  if (!isFriend && getPreviousDeclForInstantiation(Pattern)) {
1162  DeclContext::lookup_result Found = Owner->lookup(Pattern->getDeclName());
1163  if (!Found.empty()) {
1164  PrevClassTemplate = dyn_cast<ClassTemplateDecl>(Found.front());
1165  if (PrevClassTemplate)
1166  PrevDecl = PrevClassTemplate->getTemplatedDecl();
1167  }
1168  }
1169 
1170  // If this isn't a friend, then it's a member template, in which
1171  // case we just want to build the instantiation in the
1172  // specialization. If it is a friend, we want to build it in
1173  // the appropriate context.
1174  DeclContext *DC = Owner;
1175  if (isFriend) {
1176  if (QualifierLoc) {
1177  CXXScopeSpec SS;
1178  SS.Adopt(QualifierLoc);
1179  DC = SemaRef.computeDeclContext(SS);
1180  if (!DC) return nullptr;
1181  } else {
1182  DC = SemaRef.FindInstantiatedContext(Pattern->getLocation(),
1183  Pattern->getDeclContext(),
1184  TemplateArgs);
1185  }
1186 
1187  // Look for a previous declaration of the template in the owning
1188  // context.
1189  LookupResult R(SemaRef, Pattern->getDeclName(), Pattern->getLocation(),
1191  SemaRef.forRedeclarationInCurContext());
1192  SemaRef.LookupQualifiedName(R, DC);
1193 
1194  if (R.isSingleResult()) {
1195  PrevClassTemplate = R.getAsSingle<ClassTemplateDecl>();
1196  if (PrevClassTemplate)
1197  PrevDecl = PrevClassTemplate->getTemplatedDecl();
1198  }
1199 
1200  if (!PrevClassTemplate && QualifierLoc) {
1201  SemaRef.Diag(Pattern->getLocation(), diag::err_not_tag_in_scope)
1202  << D->getTemplatedDecl()->getTagKind() << Pattern->getDeclName() << DC
1203  << QualifierLoc.getSourceRange();
1204  return nullptr;
1205  }
1206 
1207  bool AdoptedPreviousTemplateParams = false;
1208  if (PrevClassTemplate) {
1209  bool Complain = true;
1210 
1211  // HACK: libstdc++ 4.2.1 contains an ill-formed friend class
1212  // template for struct std::tr1::__detail::_Map_base, where the
1213  // template parameters of the friend declaration don't match the
1214  // template parameters of the original declaration. In this one
1215  // case, we don't complain about the ill-formed friend
1216  // declaration.
1217  if (isFriend && Pattern->getIdentifier() &&
1218  Pattern->getIdentifier()->isStr("_Map_base") &&
1219  DC->isNamespace() &&
1220  cast<NamespaceDecl>(DC)->getIdentifier() &&
1221  cast<NamespaceDecl>(DC)->getIdentifier()->isStr("__detail")) {
1222  DeclContext *DCParent = DC->getParent();
1223  if (DCParent->isNamespace() &&
1224  cast<NamespaceDecl>(DCParent)->getIdentifier() &&
1225  cast<NamespaceDecl>(DCParent)->getIdentifier()->isStr("tr1")) {
1226  if (cast<Decl>(DCParent)->isInStdNamespace())
1227  Complain = false;
1228  }
1229  }
1230 
1231  TemplateParameterList *PrevParams
1232  = PrevClassTemplate->getTemplateParameters();
1233 
1234  // Make sure the parameter lists match.
1235  if (!SemaRef.TemplateParameterListsAreEqual(InstParams, PrevParams,
1236  Complain,
1238  if (Complain)
1239  return nullptr;
1240 
1241  AdoptedPreviousTemplateParams = true;
1242  InstParams = PrevParams;
1243  }
1244 
1245  // Do some additional validation, then merge default arguments
1246  // from the existing declarations.
1247  if (!AdoptedPreviousTemplateParams &&
1248  SemaRef.CheckTemplateParameterList(InstParams, PrevParams,
1250  return nullptr;
1251  }
1252  }
1253 
1254  CXXRecordDecl *RecordInst
1255  = CXXRecordDecl::Create(SemaRef.Context, Pattern->getTagKind(), DC,
1256  Pattern->getLocStart(), Pattern->getLocation(),
1257  Pattern->getIdentifier(), PrevDecl,
1258  /*DelayTypeCreation=*/true);
1259 
1260  if (QualifierLoc)
1261  RecordInst->setQualifierInfo(QualifierLoc);
1262 
1263  ClassTemplateDecl *Inst
1264  = ClassTemplateDecl::Create(SemaRef.Context, DC, D->getLocation(),
1265  D->getIdentifier(), InstParams, RecordInst);
1266  assert(!(isFriend && Owner->isDependentContext()));
1267  Inst->setPreviousDecl(PrevClassTemplate);
1268 
1269  RecordInst->setDescribedClassTemplate(Inst);
1270 
1271  if (isFriend) {
1272  if (PrevClassTemplate)
1273  Inst->setAccess(PrevClassTemplate->getAccess());
1274  else
1275  Inst->setAccess(D->getAccess());
1276 
1277  Inst->setObjectOfFriendDecl();
1278  // TODO: do we want to track the instantiation progeny of this
1279  // friend target decl?
1280  } else {
1281  Inst->setAccess(D->getAccess());
1282  if (!PrevClassTemplate)
1284  }
1285 
1286  // Trigger creation of the type for the instantiation.
1287  SemaRef.Context.getInjectedClassNameType(RecordInst,
1289 
1290  // Finish handling of friends.
1291  if (isFriend) {
1292  DC->makeDeclVisibleInContext(Inst);
1293  Inst->setLexicalDeclContext(Owner);
1294  RecordInst->setLexicalDeclContext(Owner);
1295  return Inst;
1296  }
1297 
1298  if (D->isOutOfLine()) {
1300  RecordInst->setLexicalDeclContext(D->getLexicalDeclContext());
1301  }
1302 
1303  Owner->addDecl(Inst);
1304 
1305  if (!PrevClassTemplate) {
1306  // Queue up any out-of-line partial specializations of this member
1307  // class template; the client will force their instantiation once
1308  // the enclosing class has been instantiated.
1310  D->getPartialSpecializations(PartialSpecs);
1311  for (unsigned I = 0, N = PartialSpecs.size(); I != N; ++I)
1312  if (PartialSpecs[I]->getFirstDecl()->isOutOfLine())
1313  OutOfLinePartialSpecs.push_back(std::make_pair(Inst, PartialSpecs[I]));
1314  }
1315 
1316  return Inst;
1317 }
1318 
1319 Decl *
1320 TemplateDeclInstantiator::VisitClassTemplatePartialSpecializationDecl(
1322  ClassTemplateDecl *ClassTemplate = D->getSpecializedTemplate();
1323 
1324  // Lookup the already-instantiated declaration in the instantiation
1325  // of the class template and return that.
1327  = Owner->lookup(ClassTemplate->getDeclName());
1328  if (Found.empty())
1329  return nullptr;
1330 
1331  ClassTemplateDecl *InstClassTemplate
1332  = dyn_cast<ClassTemplateDecl>(Found.front());
1333  if (!InstClassTemplate)
1334  return nullptr;
1335 
1337  = InstClassTemplate->findPartialSpecInstantiatedFromMember(D))
1338  return Result;
1339 
1340  return InstantiateClassTemplatePartialSpecialization(InstClassTemplate, D);
1341 }
1342 
1343 Decl *TemplateDeclInstantiator::VisitVarTemplateDecl(VarTemplateDecl *D) {
1344  assert(D->getTemplatedDecl()->isStaticDataMember() &&
1345  "Only static data member templates are allowed.");
1346 
1347  // Create a local instantiation scope for this variable template, which
1348  // will contain the instantiations of the template parameters.
1349  LocalInstantiationScope Scope(SemaRef);
1350  TemplateParameterList *TempParams = D->getTemplateParameters();
1351  TemplateParameterList *InstParams = SubstTemplateParams(TempParams);
1352  if (!InstParams)
1353  return nullptr;
1354 
1355  VarDecl *Pattern = D->getTemplatedDecl();
1356  VarTemplateDecl *PrevVarTemplate = nullptr;
1357 
1358  if (getPreviousDeclForInstantiation(Pattern)) {
1359  DeclContext::lookup_result Found = Owner->lookup(Pattern->getDeclName());
1360  if (!Found.empty())
1361  PrevVarTemplate = dyn_cast<VarTemplateDecl>(Found.front());
1362  }
1363 
1364  VarDecl *VarInst =
1365  cast_or_null<VarDecl>(VisitVarDecl(Pattern,
1366  /*InstantiatingVarTemplate=*/true));
1367  if (!VarInst) return nullptr;
1368 
1369  DeclContext *DC = Owner;
1370 
1372  SemaRef.Context, DC, D->getLocation(), D->getIdentifier(), InstParams,
1373  VarInst);
1374  VarInst->setDescribedVarTemplate(Inst);
1375  Inst->setPreviousDecl(PrevVarTemplate);
1376 
1377  Inst->setAccess(D->getAccess());
1378  if (!PrevVarTemplate)
1380 
1381  if (D->isOutOfLine()) {
1384  }
1385 
1386  Owner->addDecl(Inst);
1387 
1388  if (!PrevVarTemplate) {
1389  // Queue up any out-of-line partial specializations of this member
1390  // variable template; the client will force their instantiation once
1391  // the enclosing class has been instantiated.
1393  D->getPartialSpecializations(PartialSpecs);
1394  for (unsigned I = 0, N = PartialSpecs.size(); I != N; ++I)
1395  if (PartialSpecs[I]->getFirstDecl()->isOutOfLine())
1396  OutOfLineVarPartialSpecs.push_back(
1397  std::make_pair(Inst, PartialSpecs[I]));
1398  }
1399 
1400  return Inst;
1401 }
1402 
1403 Decl *TemplateDeclInstantiator::VisitVarTemplatePartialSpecializationDecl(
1405  assert(D->isStaticDataMember() &&
1406  "Only static data member templates are allowed.");
1407 
1408  VarTemplateDecl *VarTemplate = D->getSpecializedTemplate();
1409 
1410  // Lookup the already-instantiated declaration and return that.
1411  DeclContext::lookup_result Found = Owner->lookup(VarTemplate->getDeclName());
1412  assert(!Found.empty() && "Instantiation found nothing?");
1413 
1414  VarTemplateDecl *InstVarTemplate = dyn_cast<VarTemplateDecl>(Found.front());
1415  assert(InstVarTemplate && "Instantiation did not find a variable template?");
1416 
1418  InstVarTemplate->findPartialSpecInstantiatedFromMember(D))
1419  return Result;
1420 
1421  return InstantiateVarTemplatePartialSpecialization(InstVarTemplate, D);
1422 }
1423 
1424 Decl *
1425 TemplateDeclInstantiator::VisitFunctionTemplateDecl(FunctionTemplateDecl *D) {
1426  // Create a local instantiation scope for this function template, which
1427  // will contain the instantiations of the template parameters and then get
1428  // merged with the local instantiation scope for the function template
1429  // itself.
1430  LocalInstantiationScope Scope(SemaRef);
1431 
1432  TemplateParameterList *TempParams = D->getTemplateParameters();
1433  TemplateParameterList *InstParams = SubstTemplateParams(TempParams);
1434  if (!InstParams)
1435  return nullptr;
1436 
1437  FunctionDecl *Instantiated = nullptr;
1438  if (CXXMethodDecl *DMethod = dyn_cast<CXXMethodDecl>(D->getTemplatedDecl()))
1439  Instantiated = cast_or_null<FunctionDecl>(VisitCXXMethodDecl(DMethod,
1440  InstParams));
1441  else
1442  Instantiated = cast_or_null<FunctionDecl>(VisitFunctionDecl(
1443  D->getTemplatedDecl(),
1444  InstParams));
1445 
1446  if (!Instantiated)
1447  return nullptr;
1448 
1449  // Link the instantiated function template declaration to the function
1450  // template from which it was instantiated.
1451  FunctionTemplateDecl *InstTemplate
1452  = Instantiated->getDescribedFunctionTemplate();
1453  InstTemplate->setAccess(D->getAccess());
1454  assert(InstTemplate &&
1455  "VisitFunctionDecl/CXXMethodDecl didn't create a template!");
1456 
1457  bool isFriend = (InstTemplate->getFriendObjectKind() != Decl::FOK_None);
1458 
1459  // Link the instantiation back to the pattern *unless* this is a
1460  // non-definition friend declaration.
1461  if (!InstTemplate->getInstantiatedFromMemberTemplate() &&
1462  !(isFriend && !D->getTemplatedDecl()->isThisDeclarationADefinition()))
1463  InstTemplate->setInstantiatedFromMemberTemplate(D);
1464 
1465  // Make declarations visible in the appropriate context.
1466  if (!isFriend) {
1467  Owner->addDecl(InstTemplate);
1468  } else if (InstTemplate->getDeclContext()->isRecord() &&
1470  SemaRef.CheckFriendAccess(InstTemplate);
1471  }
1472 
1473  return InstTemplate;
1474 }
1475 
1476 Decl *TemplateDeclInstantiator::VisitCXXRecordDecl(CXXRecordDecl *D) {
1477  CXXRecordDecl *PrevDecl = nullptr;
1478  if (D->isInjectedClassName())
1479  PrevDecl = cast<CXXRecordDecl>(Owner);
1480  else if (CXXRecordDecl *PatternPrev = getPreviousDeclForInstantiation(D)) {
1481  NamedDecl *Prev = SemaRef.FindInstantiatedDecl(D->getLocation(),
1482  PatternPrev,
1483  TemplateArgs);
1484  if (!Prev) return nullptr;
1485  PrevDecl = cast<CXXRecordDecl>(Prev);
1486  }
1487 
1488  CXXRecordDecl *Record
1489  = CXXRecordDecl::Create(SemaRef.Context, D->getTagKind(), Owner,
1490  D->getLocStart(), D->getLocation(),
1491  D->getIdentifier(), PrevDecl);
1492 
1493  // Substitute the nested name specifier, if any.
1494  if (SubstQualifier(D, Record))
1495  return nullptr;
1496 
1497  Record->setImplicit(D->isImplicit());
1498  // FIXME: Check against AS_none is an ugly hack to work around the issue that
1499  // the tag decls introduced by friend class declarations don't have an access
1500  // specifier. Remove once this area of the code gets sorted out.
1501  if (D->getAccess() != AS_none)
1502  Record->setAccess(D->getAccess());
1503  if (!D->isInjectedClassName())
1504  Record->setInstantiationOfMemberClass(D, TSK_ImplicitInstantiation);
1505 
1506  // If the original function was part of a friend declaration,
1507  // inherit its namespace state.
1508  if (D->getFriendObjectKind())
1509  Record->setObjectOfFriendDecl();
1510 
1511  // Make sure that anonymous structs and unions are recorded.
1512  if (D->isAnonymousStructOrUnion())
1513  Record->setAnonymousStructOrUnion(true);
1514 
1515  if (D->isLocalClass())
1516  SemaRef.CurrentInstantiationScope->InstantiatedLocal(D, Record);
1517 
1518  // Forward the mangling number from the template to the instantiated decl.
1519  SemaRef.Context.setManglingNumber(Record,
1520  SemaRef.Context.getManglingNumber(D));
1521 
1522  // See if the old tag was defined along with a declarator.
1523  // If it did, mark the new tag as being associated with that declarator.
1525  SemaRef.Context.addDeclaratorForUnnamedTagDecl(Record, DD);
1526 
1527  // See if the old tag was defined along with a typedef.
1528  // If it did, mark the new tag as being associated with that typedef.
1530  SemaRef.Context.addTypedefNameForUnnamedTagDecl(Record, TND);
1531 
1532  Owner->addDecl(Record);
1533 
1534  // DR1484 clarifies that the members of a local class are instantiated as part
1535  // of the instantiation of their enclosing entity.
1536  if (D->isCompleteDefinition() && D->isLocalClass()) {
1537  Sema::LocalEagerInstantiationScope LocalInstantiations(SemaRef);
1538 
1539  SemaRef.InstantiateClass(D->getLocation(), Record, D, TemplateArgs,
1541  /*Complain=*/true);
1542 
1543  // For nested local classes, we will instantiate the members when we
1544  // reach the end of the outermost (non-nested) local class.
1545  if (!D->isCXXClassMember())
1546  SemaRef.InstantiateClassMembers(D->getLocation(), Record, TemplateArgs,
1548 
1549  // This class may have local implicit instantiations that need to be
1550  // performed within this scope.
1551  LocalInstantiations.perform();
1552  }
1553 
1554  SemaRef.DiagnoseUnusedNestedTypedefs(Record);
1555 
1556  return Record;
1557 }
1558 
1559 /// Adjust the given function type for an instantiation of the
1560 /// given declaration, to cope with modifications to the function's type that
1561 /// aren't reflected in the type-source information.
1562 ///
1563 /// \param D The declaration we're instantiating.
1564 /// \param TInfo The already-instantiated type.
1566  FunctionDecl *D,
1567  TypeSourceInfo *TInfo) {
1568  const FunctionProtoType *OrigFunc
1569  = D->getType()->castAs<FunctionProtoType>();
1570  const FunctionProtoType *NewFunc
1571  = TInfo->getType()->castAs<FunctionProtoType>();
1572  if (OrigFunc->getExtInfo() == NewFunc->getExtInfo())
1573  return TInfo->getType();
1574 
1575  FunctionProtoType::ExtProtoInfo NewEPI = NewFunc->getExtProtoInfo();
1576  NewEPI.ExtInfo = OrigFunc->getExtInfo();
1577  return Context.getFunctionType(NewFunc->getReturnType(),
1578  NewFunc->getParamTypes(), NewEPI);
1579 }
1580 
1581 /// Normal class members are of more specific types and therefore
1582 /// don't make it here. This function serves three purposes:
1583 /// 1) instantiating function templates
1584 /// 2) substituting friend declarations
1585 /// 3) substituting deduction guide declarations for nested class templates
1587  TemplateParameterList *TemplateParams) {
1588  // Check whether there is already a function template specialization for
1589  // this declaration.
1590  FunctionTemplateDecl *FunctionTemplate = D->getDescribedFunctionTemplate();
1591  if (FunctionTemplate && !TemplateParams) {
1592  ArrayRef<TemplateArgument> Innermost = TemplateArgs.getInnermost();
1593 
1594  void *InsertPos = nullptr;
1595  FunctionDecl *SpecFunc
1596  = FunctionTemplate->findSpecialization(Innermost, InsertPos);
1597 
1598  // If we already have a function template specialization, return it.
1599  if (SpecFunc)
1600  return SpecFunc;
1601  }
1602 
1603  bool isFriend;
1604  if (FunctionTemplate)
1605  isFriend = (FunctionTemplate->getFriendObjectKind() != Decl::FOK_None);
1606  else
1607  isFriend = (D->getFriendObjectKind() != Decl::FOK_None);
1608 
1609  bool MergeWithParentScope = (TemplateParams != nullptr) ||
1610  Owner->isFunctionOrMethod() ||
1611  !(isa<Decl>(Owner) &&
1612  cast<Decl>(Owner)->isDefinedOutsideFunctionOrMethod());
1613  LocalInstantiationScope Scope(SemaRef, MergeWithParentScope);
1614 
1616  TypeSourceInfo *TInfo = SubstFunctionType(D, Params);
1617  if (!TInfo)
1618  return nullptr;
1620 
1621  NestedNameSpecifierLoc QualifierLoc = D->getQualifierLoc();
1622  if (QualifierLoc) {
1623  QualifierLoc = SemaRef.SubstNestedNameSpecifierLoc(QualifierLoc,
1624  TemplateArgs);
1625  if (!QualifierLoc)
1626  return nullptr;
1627  }
1628 
1629  // If we're instantiating a local function declaration, put the result
1630  // in the enclosing namespace; otherwise we need to find the instantiated
1631  // context.
1632  DeclContext *DC;
1633  if (D->isLocalExternDecl()) {
1634  DC = Owner;
1635  SemaRef.adjustContextForLocalExternDecl(DC);
1636  } else if (isFriend && QualifierLoc) {
1637  CXXScopeSpec SS;
1638  SS.Adopt(QualifierLoc);
1639  DC = SemaRef.computeDeclContext(SS);
1640  if (!DC) return nullptr;
1641  } else {
1642  DC = SemaRef.FindInstantiatedContext(D->getLocation(), D->getDeclContext(),
1643  TemplateArgs);
1644  }
1645 
1646  DeclarationNameInfo NameInfo
1647  = SemaRef.SubstDeclarationNameInfo(D->getNameInfo(), TemplateArgs);
1648 
1649  FunctionDecl *Function;
1650  if (auto *DGuide = dyn_cast<CXXDeductionGuideDecl>(D)) {
1651  Function = CXXDeductionGuideDecl::Create(
1652  SemaRef.Context, DC, D->getInnerLocStart(), DGuide->isExplicit(),
1653  NameInfo, T, TInfo, D->getSourceRange().getEnd());
1654  if (DGuide->isCopyDeductionCandidate())
1655  cast<CXXDeductionGuideDecl>(Function)->setIsCopyDeductionCandidate();
1656  Function->setAccess(D->getAccess());
1657  } else {
1658  Function = FunctionDecl::Create(
1659  SemaRef.Context, DC, D->getInnerLocStart(), NameInfo, T, TInfo,
1661  D->hasWrittenPrototype(), D->isConstexpr());
1662  Function->setRangeEnd(D->getSourceRange().getEnd());
1663  }
1664 
1665  if (D->isInlined())
1666  Function->setImplicitlyInline();
1667 
1668  if (QualifierLoc)
1669  Function->setQualifierInfo(QualifierLoc);
1670 
1671  if (D->isLocalExternDecl())
1672  Function->setLocalExternDecl();
1673 
1674  DeclContext *LexicalDC = Owner;
1675  if (!isFriend && D->isOutOfLine() && !D->isLocalExternDecl()) {
1676  assert(D->getDeclContext()->isFileContext());
1677  LexicalDC = D->getDeclContext();
1678  }
1679 
1680  Function->setLexicalDeclContext(LexicalDC);
1681 
1682  // Attach the parameters
1683  for (unsigned P = 0; P < Params.size(); ++P)
1684  if (Params[P])
1685  Params[P]->setOwningFunction(Function);
1686  Function->setParams(Params);
1687 
1688  if (TemplateParams) {
1689  // Our resulting instantiation is actually a function template, since we
1690  // are substituting only the outer template parameters. For example, given
1691  //
1692  // template<typename T>
1693  // struct X {
1694  // template<typename U> friend void f(T, U);
1695  // };
1696  //
1697  // X<int> x;
1698  //
1699  // We are instantiating the friend function template "f" within X<int>,
1700  // which means substituting int for T, but leaving "f" as a friend function
1701  // template.
1702  // Build the function template itself.
1703  FunctionTemplate = FunctionTemplateDecl::Create(SemaRef.Context, DC,
1704  Function->getLocation(),
1705  Function->getDeclName(),
1706  TemplateParams, Function);
1707  Function->setDescribedFunctionTemplate(FunctionTemplate);
1708 
1709  FunctionTemplate->setLexicalDeclContext(LexicalDC);
1710 
1711  if (isFriend && D->isThisDeclarationADefinition()) {
1712  FunctionTemplate->setInstantiatedFromMemberTemplate(
1714  }
1715  } else if (FunctionTemplate) {
1716  // Record this function template specialization.
1717  ArrayRef<TemplateArgument> Innermost = TemplateArgs.getInnermost();
1718  Function->setFunctionTemplateSpecialization(FunctionTemplate,
1720  Innermost),
1721  /*InsertPos=*/nullptr);
1722  } else if (isFriend && D->isThisDeclarationADefinition()) {
1723  // Do not connect the friend to the template unless it's actually a
1724  // definition. We don't want non-template functions to be marked as being
1725  // template instantiations.
1726  Function->setInstantiationOfMemberFunction(D, TSK_ImplicitInstantiation);
1727  }
1728 
1729  if (InitFunctionInstantiation(Function, D))
1730  Function->setInvalidDecl();
1731 
1732  bool isExplicitSpecialization = false;
1733 
1735  SemaRef, Function->getDeclName(), SourceLocation(),
1739  : SemaRef.forRedeclarationInCurContext());
1740 
1743  assert(isFriend && "non-friend has dependent specialization info?");
1744 
1745  // This needs to be set now for future sanity.
1746  Function->setObjectOfFriendDecl();
1747 
1748  // Instantiate the explicit template arguments.
1749  TemplateArgumentListInfo ExplicitArgs(Info->getLAngleLoc(),
1750  Info->getRAngleLoc());
1751  if (SemaRef.Subst(Info->getTemplateArgs(), Info->getNumTemplateArgs(),
1752  ExplicitArgs, TemplateArgs))
1753  return nullptr;
1754 
1755  // Map the candidate templates to their instantiations.
1756  for (unsigned I = 0, E = Info->getNumTemplates(); I != E; ++I) {
1757  Decl *Temp = SemaRef.FindInstantiatedDecl(D->getLocation(),
1758  Info->getTemplate(I),
1759  TemplateArgs);
1760  if (!Temp) return nullptr;
1761 
1762  Previous.addDecl(cast<FunctionTemplateDecl>(Temp));
1763  }
1764 
1765  if (SemaRef.CheckFunctionTemplateSpecialization(Function,
1766  &ExplicitArgs,
1767  Previous))
1768  Function->setInvalidDecl();
1769 
1770  isExplicitSpecialization = true;
1771 
1772  } else if (TemplateParams || !FunctionTemplate) {
1773  // Look only into the namespace where the friend would be declared to
1774  // find a previous declaration. This is the innermost enclosing namespace,
1775  // as described in ActOnFriendFunctionDecl.
1776  SemaRef.LookupQualifiedName(Previous, DC);
1777 
1778  // In C++, the previous declaration we find might be a tag type
1779  // (class or enum). In this case, the new declaration will hide the
1780  // tag type. Note that this does does not apply if we're declaring a
1781  // typedef (C++ [dcl.typedef]p4).
1782  if (Previous.isSingleTagDecl())
1783  Previous.clear();
1784  }
1785 
1786  if (isFriend)
1787  Function->setObjectOfFriendDecl();
1788 
1789  SemaRef.CheckFunctionDeclaration(/*Scope*/ nullptr, Function, Previous,
1790  isExplicitSpecialization);
1791 
1792  NamedDecl *PrincipalDecl = (TemplateParams
1793  ? cast<NamedDecl>(FunctionTemplate)
1794  : Function);
1795 
1796  // If the original function was part of a friend declaration,
1797  // inherit its namespace state and add it to the owner.
1798  if (isFriend) {
1799  PrincipalDecl->setObjectOfFriendDecl();
1800  DC->makeDeclVisibleInContext(PrincipalDecl);
1801 
1802  bool QueuedInstantiation = false;
1803 
1804  // C++11 [temp.friend]p4 (DR329):
1805  // When a function is defined in a friend function declaration in a class
1806  // template, the function is instantiated when the function is odr-used.
1807  // The same restrictions on multiple declarations and definitions that
1808  // apply to non-template function declarations and definitions also apply
1809  // to these implicit definitions.
1810  if (D->isThisDeclarationADefinition()) {
1811  SemaRef.CheckForFunctionRedefinition(Function);
1812  if (!Function->isInvalidDecl()) {
1813  for (auto R : Function->redecls()) {
1814  if (R == Function)
1815  continue;
1816 
1817  // If some prior declaration of this function has been used, we need
1818  // to instantiate its definition.
1819  if (!QueuedInstantiation && R->isUsed(false)) {
1820  if (MemberSpecializationInfo *MSInfo =
1821  Function->getMemberSpecializationInfo()) {
1822  if (MSInfo->getPointOfInstantiation().isInvalid()) {
1823  SourceLocation Loc = R->getLocation(); // FIXME
1824  MSInfo->setPointOfInstantiation(Loc);
1825  SemaRef.PendingLocalImplicitInstantiations.push_back(
1826  std::make_pair(Function, Loc));
1827  QueuedInstantiation = true;
1828  }
1829  }
1830  }
1831  }
1832  }
1833  }
1834 
1835  // Check the template parameter list against the previous declaration. The
1836  // goal here is to pick up default arguments added since the friend was
1837  // declared; we know the template parameter lists match, since otherwise
1838  // we would not have picked this template as the previous declaration.
1839  if (TemplateParams && FunctionTemplate->getPreviousDecl()) {
1841  TemplateParams,
1842  FunctionTemplate->getPreviousDecl()->getTemplateParameters(),
1843  Function->isThisDeclarationADefinition()
1846  }
1847  }
1848 
1849  if (Function->isLocalExternDecl() && !Function->getPreviousDecl())
1850  DC->makeDeclVisibleInContext(PrincipalDecl);
1851 
1852  if (Function->isOverloadedOperator() && !DC->isRecord() &&
1854  PrincipalDecl->setNonMemberOperator();
1855 
1856  assert(!D->isDefaulted() && "only methods should be defaulted");
1857  return Function;
1858 }
1859 
1860 Decl *
1862  TemplateParameterList *TemplateParams,
1863  bool IsClassScopeSpecialization) {
1864  FunctionTemplateDecl *FunctionTemplate = D->getDescribedFunctionTemplate();
1865  if (FunctionTemplate && !TemplateParams) {
1866  // We are creating a function template specialization from a function
1867  // template. Check whether there is already a function template
1868  // specialization for this particular set of template arguments.
1869  ArrayRef<TemplateArgument> Innermost = TemplateArgs.getInnermost();
1870 
1871  void *InsertPos = nullptr;
1872  FunctionDecl *SpecFunc
1873  = FunctionTemplate->findSpecialization(Innermost, InsertPos);
1874 
1875  // If we already have a function template specialization, return it.
1876  if (SpecFunc)
1877  return SpecFunc;
1878  }
1879 
1880  bool isFriend;
1881  if (FunctionTemplate)
1882  isFriend = (FunctionTemplate->getFriendObjectKind() != Decl::FOK_None);
1883  else
1884  isFriend = (D->getFriendObjectKind() != Decl::FOK_None);
1885 
1886  bool MergeWithParentScope = (TemplateParams != nullptr) ||
1887  !(isa<Decl>(Owner) &&
1888  cast<Decl>(Owner)->isDefinedOutsideFunctionOrMethod());
1889  LocalInstantiationScope Scope(SemaRef, MergeWithParentScope);
1890 
1891  // Instantiate enclosing template arguments for friends.
1893  unsigned NumTempParamLists = 0;
1894  if (isFriend && (NumTempParamLists = D->getNumTemplateParameterLists())) {
1895  TempParamLists.resize(NumTempParamLists);
1896  for (unsigned I = 0; I != NumTempParamLists; ++I) {
1897  TemplateParameterList *TempParams = D->getTemplateParameterList(I);
1898  TemplateParameterList *InstParams = SubstTemplateParams(TempParams);
1899  if (!InstParams)
1900  return nullptr;
1901  TempParamLists[I] = InstParams;
1902  }
1903  }
1904 
1906  TypeSourceInfo *TInfo = SubstFunctionType(D, Params);
1907  if (!TInfo)
1908  return nullptr;
1910 
1911  NestedNameSpecifierLoc QualifierLoc = D->getQualifierLoc();
1912  if (QualifierLoc) {
1913  QualifierLoc = SemaRef.SubstNestedNameSpecifierLoc(QualifierLoc,
1914  TemplateArgs);
1915  if (!QualifierLoc)
1916  return nullptr;
1917  }
1918 
1919  DeclContext *DC = Owner;
1920  if (isFriend) {
1921  if (QualifierLoc) {
1922  CXXScopeSpec SS;
1923  SS.Adopt(QualifierLoc);
1924  DC = SemaRef.computeDeclContext(SS);
1925 
1926  if (DC && SemaRef.RequireCompleteDeclContext(SS, DC))
1927  return nullptr;
1928  } else {
1929  DC = SemaRef.FindInstantiatedContext(D->getLocation(),
1930  D->getDeclContext(),
1931  TemplateArgs);
1932  }
1933  if (!DC) return nullptr;
1934  }
1935 
1936  // Build the instantiated method declaration.
1937  CXXRecordDecl *Record = cast<CXXRecordDecl>(DC);
1938  CXXMethodDecl *Method = nullptr;
1939 
1940  SourceLocation StartLoc = D->getInnerLocStart();
1941  DeclarationNameInfo NameInfo
1942  = SemaRef.SubstDeclarationNameInfo(D->getNameInfo(), TemplateArgs);
1943  if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(D)) {
1944  Method = CXXConstructorDecl::Create(SemaRef.Context, Record,
1945  StartLoc, NameInfo, T, TInfo,
1946  Constructor->isExplicit(),
1947  Constructor->isInlineSpecified(),
1948  false, Constructor->isConstexpr());
1949  Method->setRangeEnd(Constructor->getLocEnd());
1950  } else if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(D)) {
1951  Method = CXXDestructorDecl::Create(SemaRef.Context, Record,
1952  StartLoc, NameInfo, T, TInfo,
1953  Destructor->isInlineSpecified(),
1954  false);
1955  Method->setRangeEnd(Destructor->getLocEnd());
1956  } else if (CXXConversionDecl *Conversion = dyn_cast<CXXConversionDecl>(D)) {
1957  Method = CXXConversionDecl::Create(SemaRef.Context, Record,
1958  StartLoc, NameInfo, T, TInfo,
1959  Conversion->isInlineSpecified(),
1960  Conversion->isExplicit(),
1961  Conversion->isConstexpr(),
1962  Conversion->getLocEnd());
1963  } else {
1964  StorageClass SC = D->isStatic() ? SC_Static : SC_None;
1965  Method = CXXMethodDecl::Create(SemaRef.Context, Record,
1966  StartLoc, NameInfo, T, TInfo,
1967  SC, D->isInlineSpecified(),
1968  D->isConstexpr(), D->getLocEnd());
1969  }
1970 
1971  if (D->isInlined())
1972  Method->setImplicitlyInline();
1973 
1974  if (QualifierLoc)
1975  Method->setQualifierInfo(QualifierLoc);
1976 
1977  if (TemplateParams) {
1978  // Our resulting instantiation is actually a function template, since we
1979  // are substituting only the outer template parameters. For example, given
1980  //
1981  // template<typename T>
1982  // struct X {
1983  // template<typename U> void f(T, U);
1984  // };
1985  //
1986  // X<int> x;
1987  //
1988  // We are instantiating the member template "f" within X<int>, which means
1989  // substituting int for T, but leaving "f" as a member function template.
1990  // Build the function template itself.
1991  FunctionTemplate = FunctionTemplateDecl::Create(SemaRef.Context, Record,
1992  Method->getLocation(),
1993  Method->getDeclName(),
1994  TemplateParams, Method);
1995  if (isFriend) {
1996  FunctionTemplate->setLexicalDeclContext(Owner);
1997  FunctionTemplate->setObjectOfFriendDecl();
1998  } else if (D->isOutOfLine())
1999  FunctionTemplate->setLexicalDeclContext(D->getLexicalDeclContext());
2000  Method->setDescribedFunctionTemplate(FunctionTemplate);
2001  } else if (FunctionTemplate) {
2002  // Record this function template specialization.
2003  ArrayRef<TemplateArgument> Innermost = TemplateArgs.getInnermost();
2004  Method->setFunctionTemplateSpecialization(FunctionTemplate,
2006  Innermost),
2007  /*InsertPos=*/nullptr);
2008  } else if (!isFriend) {
2009  // Record that this is an instantiation of a member function.
2010  Method->setInstantiationOfMemberFunction(D, TSK_ImplicitInstantiation);
2011  }
2012 
2013  // If we are instantiating a member function defined
2014  // out-of-line, the instantiation will have the same lexical
2015  // context (which will be a namespace scope) as the template.
2016  if (isFriend) {
2017  if (NumTempParamLists)
2018  Method->setTemplateParameterListsInfo(
2019  SemaRef.Context,
2020  llvm::makeArrayRef(TempParamLists.data(), NumTempParamLists));
2021 
2022  Method->setLexicalDeclContext(Owner);
2023  Method->setObjectOfFriendDecl();
2024  } else if (D->isOutOfLine())
2025  Method->setLexicalDeclContext(D->getLexicalDeclContext());
2026 
2027  // Attach the parameters
2028  for (unsigned P = 0; P < Params.size(); ++P)
2029  Params[P]->setOwningFunction(Method);
2030  Method->setParams(Params);
2031 
2032  if (InitMethodInstantiation(Method, D))
2033  Method->setInvalidDecl();
2034 
2035  LookupResult Previous(SemaRef, NameInfo, Sema::LookupOrdinaryName,
2037 
2038  if (!FunctionTemplate || TemplateParams || isFriend) {
2039  SemaRef.LookupQualifiedName(Previous, Record);
2040 
2041  // In C++, the previous declaration we find might be a tag type
2042  // (class or enum). In this case, the new declaration will hide the
2043  // tag type. Note that this does does not apply if we're declaring a
2044  // typedef (C++ [dcl.typedef]p4).
2045  if (Previous.isSingleTagDecl())
2046  Previous.clear();
2047  }
2048 
2049  if (!IsClassScopeSpecialization)
2050  SemaRef.CheckFunctionDeclaration(nullptr, Method, Previous, false);
2051 
2052  if (D->isPure())
2053  SemaRef.CheckPureMethod(Method, SourceRange());
2054 
2055  // Propagate access. For a non-friend declaration, the access is
2056  // whatever we're propagating from. For a friend, it should be the
2057  // previous declaration we just found.
2058  if (isFriend && Method->getPreviousDecl())
2059  Method->setAccess(Method->getPreviousDecl()->getAccess());
2060  else
2061  Method->setAccess(D->getAccess());
2062  if (FunctionTemplate)
2063  FunctionTemplate->setAccess(Method->getAccess());
2064 
2065  SemaRef.CheckOverrideControl(Method);
2066 
2067  // If a function is defined as defaulted or deleted, mark it as such now.
2068  if (D->isExplicitlyDefaulted())
2069  SemaRef.SetDeclDefaulted(Method, Method->getLocation());
2070  if (D->isDeletedAsWritten())
2071  SemaRef.SetDeclDeleted(Method, Method->getLocation());
2072 
2073  // If there's a function template, let our caller handle it.
2074  if (FunctionTemplate) {
2075  // do nothing
2076 
2077  // Don't hide a (potentially) valid declaration with an invalid one.
2078  } else if (Method->isInvalidDecl() && !Previous.empty()) {
2079  // do nothing
2080 
2081  // Otherwise, check access to friends and make them visible.
2082  } else if (isFriend) {
2083  // We only need to re-check access for methods which we didn't
2084  // manage to match during parsing.
2085  if (!D->getPreviousDecl())
2086  SemaRef.CheckFriendAccess(Method);
2087 
2088  Record->makeDeclVisibleInContext(Method);
2089 
2090  // Otherwise, add the declaration. We don't need to do this for
2091  // class-scope specializations because we'll have matched them with
2092  // the appropriate template.
2093  } else if (!IsClassScopeSpecialization) {
2094  Owner->addDecl(Method);
2095  }
2096 
2097  return Method;
2098 }
2099 
2100 Decl *TemplateDeclInstantiator::VisitCXXConstructorDecl(CXXConstructorDecl *D) {
2101  return VisitCXXMethodDecl(D);
2102 }
2103 
2104 Decl *TemplateDeclInstantiator::VisitCXXDestructorDecl(CXXDestructorDecl *D) {
2105  return VisitCXXMethodDecl(D);
2106 }
2107 
2108 Decl *TemplateDeclInstantiator::VisitCXXConversionDecl(CXXConversionDecl *D) {
2109  return VisitCXXMethodDecl(D);
2110 }
2111 
2112 Decl *TemplateDeclInstantiator::VisitParmVarDecl(ParmVarDecl *D) {
2113  return SemaRef.SubstParmVarDecl(D, TemplateArgs, /*indexAdjustment*/ 0, None,
2114  /*ExpectParameterPack=*/ false);
2115 }
2116 
2117 Decl *TemplateDeclInstantiator::VisitTemplateTypeParmDecl(
2118  TemplateTypeParmDecl *D) {
2119  // TODO: don't always clone when decls are refcounted.
2120  assert(D->getTypeForDecl()->isTemplateTypeParmType());
2121 
2123  SemaRef.Context, Owner, D->getLocStart(), D->getLocation(),
2124  D->getDepth() - TemplateArgs.getNumSubstitutedLevels(), D->getIndex(),
2126  Inst->setAccess(AS_public);
2127 
2128  if (D->hasDefaultArgument() && !D->defaultArgumentWasInherited()) {
2129  TypeSourceInfo *InstantiatedDefaultArg =
2130  SemaRef.SubstType(D->getDefaultArgumentInfo(), TemplateArgs,
2131  D->getDefaultArgumentLoc(), D->getDeclName());
2132  if (InstantiatedDefaultArg)
2133  Inst->setDefaultArgument(InstantiatedDefaultArg);
2134  }
2135 
2136  // Introduce this template parameter's instantiation into the instantiation
2137  // scope.
2138  SemaRef.CurrentInstantiationScope->InstantiatedLocal(D, Inst);
2139 
2140  return Inst;
2141 }
2142 
2143 Decl *TemplateDeclInstantiator::VisitNonTypeTemplateParmDecl(
2145  // Substitute into the type of the non-type template parameter.
2146  TypeLoc TL = D->getTypeSourceInfo()->getTypeLoc();
2147  SmallVector<TypeSourceInfo *, 4> ExpandedParameterPackTypesAsWritten;
2148  SmallVector<QualType, 4> ExpandedParameterPackTypes;
2149  bool IsExpandedParameterPack = false;
2150  TypeSourceInfo *DI;
2151  QualType T;
2152  bool Invalid = false;
2153 
2154  if (D->isExpandedParameterPack()) {
2155  // The non-type template parameter pack is an already-expanded pack
2156  // expansion of types. Substitute into each of the expanded types.
2157  ExpandedParameterPackTypes.reserve(D->getNumExpansionTypes());
2158  ExpandedParameterPackTypesAsWritten.reserve(D->getNumExpansionTypes());
2159  for (unsigned I = 0, N = D->getNumExpansionTypes(); I != N; ++I) {
2160  TypeSourceInfo *NewDI =
2161  SemaRef.SubstType(D->getExpansionTypeSourceInfo(I), TemplateArgs,
2162  D->getLocation(), D->getDeclName());
2163  if (!NewDI)
2164  return nullptr;
2165 
2166  QualType NewT =
2167  SemaRef.CheckNonTypeTemplateParameterType(NewDI, D->getLocation());
2168  if (NewT.isNull())
2169  return nullptr;
2170 
2171  ExpandedParameterPackTypesAsWritten.push_back(NewDI);
2172  ExpandedParameterPackTypes.push_back(NewT);
2173  }
2174 
2175  IsExpandedParameterPack = true;
2176  DI = D->getTypeSourceInfo();
2177  T = DI->getType();
2178  } else if (D->isPackExpansion()) {
2179  // The non-type template parameter pack's type is a pack expansion of types.
2180  // Determine whether we need to expand this parameter pack into separate
2181  // types.
2183  TypeLoc Pattern = Expansion.getPatternLoc();
2185  SemaRef.collectUnexpandedParameterPacks(Pattern, Unexpanded);
2186 
2187  // Determine whether the set of unexpanded parameter packs can and should
2188  // be expanded.
2189  bool Expand = true;
2190  bool RetainExpansion = false;
2191  Optional<unsigned> OrigNumExpansions
2192  = Expansion.getTypePtr()->getNumExpansions();
2193  Optional<unsigned> NumExpansions = OrigNumExpansions;
2194  if (SemaRef.CheckParameterPacksForExpansion(Expansion.getEllipsisLoc(),
2195  Pattern.getSourceRange(),
2196  Unexpanded,
2197  TemplateArgs,
2198  Expand, RetainExpansion,
2199  NumExpansions))
2200  return nullptr;
2201 
2202  if (Expand) {
2203  for (unsigned I = 0; I != *NumExpansions; ++I) {
2204  Sema::ArgumentPackSubstitutionIndexRAII SubstIndex(SemaRef, I);
2205  TypeSourceInfo *NewDI = SemaRef.SubstType(Pattern, TemplateArgs,
2206  D->getLocation(),
2207  D->getDeclName());
2208  if (!NewDI)
2209  return nullptr;
2210 
2211  QualType NewT =
2212  SemaRef.CheckNonTypeTemplateParameterType(NewDI, D->getLocation());
2213  if (NewT.isNull())
2214  return nullptr;
2215 
2216  ExpandedParameterPackTypesAsWritten.push_back(NewDI);
2217  ExpandedParameterPackTypes.push_back(NewT);
2218  }
2219 
2220  // Note that we have an expanded parameter pack. The "type" of this
2221  // expanded parameter pack is the original expansion type, but callers
2222  // will end up using the expanded parameter pack types for type-checking.
2223  IsExpandedParameterPack = true;
2224  DI = D->getTypeSourceInfo();
2225  T = DI->getType();
2226  } else {
2227  // We cannot fully expand the pack expansion now, so substitute into the
2228  // pattern and create a new pack expansion type.
2229  Sema::ArgumentPackSubstitutionIndexRAII SubstIndex(SemaRef, -1);
2230  TypeSourceInfo *NewPattern = SemaRef.SubstType(Pattern, TemplateArgs,
2231  D->getLocation(),
2232  D->getDeclName());
2233  if (!NewPattern)
2234  return nullptr;
2235 
2236  SemaRef.CheckNonTypeTemplateParameterType(NewPattern, D->getLocation());
2237  DI = SemaRef.CheckPackExpansion(NewPattern, Expansion.getEllipsisLoc(),
2238  NumExpansions);
2239  if (!DI)
2240  return nullptr;
2241 
2242  T = DI->getType();
2243  }
2244  } else {
2245  // Simple case: substitution into a parameter that is not a parameter pack.
2246  DI = SemaRef.SubstType(D->getTypeSourceInfo(), TemplateArgs,
2247  D->getLocation(), D->getDeclName());
2248  if (!DI)
2249  return nullptr;
2250 
2251  // Check that this type is acceptable for a non-type template parameter.
2252  T = SemaRef.CheckNonTypeTemplateParameterType(DI, D->getLocation());
2253  if (T.isNull()) {
2254  T = SemaRef.Context.IntTy;
2255  Invalid = true;
2256  }
2257  }
2258 
2259  NonTypeTemplateParmDecl *Param;
2260  if (IsExpandedParameterPack)
2262  SemaRef.Context, Owner, D->getInnerLocStart(), D->getLocation(),
2263  D->getDepth() - TemplateArgs.getNumSubstitutedLevels(),
2264  D->getPosition(), D->getIdentifier(), T, DI, ExpandedParameterPackTypes,
2265  ExpandedParameterPackTypesAsWritten);
2266  else
2268  SemaRef.Context, Owner, D->getInnerLocStart(), D->getLocation(),
2269  D->getDepth() - TemplateArgs.getNumSubstitutedLevels(),
2270  D->getPosition(), D->getIdentifier(), T, D->isParameterPack(), DI);
2271 
2272  Param->setAccess(AS_public);
2273  if (Invalid)
2274  Param->setInvalidDecl();
2275 
2276  if (D->hasDefaultArgument() && !D->defaultArgumentWasInherited()) {
2277  EnterExpressionEvaluationContext ConstantEvaluated(
2279  ExprResult Value = SemaRef.SubstExpr(D->getDefaultArgument(), TemplateArgs);
2280  if (!Value.isInvalid())
2281  Param->setDefaultArgument(Value.get());
2282  }
2283 
2284  // Introduce this template parameter's instantiation into the instantiation
2285  // scope.
2286  SemaRef.CurrentInstantiationScope->InstantiatedLocal(D, Param);
2287  return Param;
2288 }
2289 
2291  Sema &S,
2292  TemplateParameterList *Params,
2294  for (const auto &P : *Params) {
2295  if (P->isTemplateParameterPack())
2296  continue;
2297  if (NonTypeTemplateParmDecl *NTTP = dyn_cast<NonTypeTemplateParmDecl>(P))
2298  S.collectUnexpandedParameterPacks(NTTP->getTypeSourceInfo()->getTypeLoc(),
2299  Unexpanded);
2300  if (TemplateTemplateParmDecl *TTP = dyn_cast<TemplateTemplateParmDecl>(P))
2301  collectUnexpandedParameterPacks(S, TTP->getTemplateParameters(),
2302  Unexpanded);
2303  }
2304 }
2305 
2306 Decl *
2307 TemplateDeclInstantiator::VisitTemplateTemplateParmDecl(
2309  // Instantiate the template parameter list of the template template parameter.
2310  TemplateParameterList *TempParams = D->getTemplateParameters();
2311  TemplateParameterList *InstParams;
2313 
2314  bool IsExpandedParameterPack = false;
2315 
2316  if (D->isExpandedParameterPack()) {
2317  // The template template parameter pack is an already-expanded pack
2318  // expansion of template parameters. Substitute into each of the expanded
2319  // parameters.
2320  ExpandedParams.reserve(D->getNumExpansionTemplateParameters());
2321  for (unsigned I = 0, N = D->getNumExpansionTemplateParameters();
2322  I != N; ++I) {
2323  LocalInstantiationScope Scope(SemaRef);
2324  TemplateParameterList *Expansion =
2326  if (!Expansion)
2327  return nullptr;
2328  ExpandedParams.push_back(Expansion);
2329  }
2330 
2331  IsExpandedParameterPack = true;
2332  InstParams = TempParams;
2333  } else if (D->isPackExpansion()) {
2334  // The template template parameter pack expands to a pack of template
2335  // template parameters. Determine whether we need to expand this parameter
2336  // pack into separate parameters.
2339  Unexpanded);
2340 
2341  // Determine whether the set of unexpanded parameter packs can and should
2342  // be expanded.
2343  bool Expand = true;
2344  bool RetainExpansion = false;
2345  Optional<unsigned> NumExpansions;
2347  TempParams->getSourceRange(),
2348  Unexpanded,
2349  TemplateArgs,
2350  Expand, RetainExpansion,
2351  NumExpansions))
2352  return nullptr;
2353 
2354  if (Expand) {
2355  for (unsigned I = 0; I != *NumExpansions; ++I) {
2356  Sema::ArgumentPackSubstitutionIndexRAII SubstIndex(SemaRef, I);
2357  LocalInstantiationScope Scope(SemaRef);
2358  TemplateParameterList *Expansion = SubstTemplateParams(TempParams);
2359  if (!Expansion)
2360  return nullptr;
2361  ExpandedParams.push_back(Expansion);
2362  }
2363 
2364  // Note that we have an expanded parameter pack. The "type" of this
2365  // expanded parameter pack is the original expansion type, but callers
2366  // will end up using the expanded parameter pack types for type-checking.
2367  IsExpandedParameterPack = true;
2368  InstParams = TempParams;
2369  } else {
2370  // We cannot fully expand the pack expansion now, so just substitute
2371  // into the pattern.
2372  Sema::ArgumentPackSubstitutionIndexRAII SubstIndex(SemaRef, -1);
2373 
2374  LocalInstantiationScope Scope(SemaRef);
2375  InstParams = SubstTemplateParams(TempParams);
2376  if (!InstParams)
2377  return nullptr;
2378  }
2379  } else {
2380  // Perform the actual substitution of template parameters within a new,
2381  // local instantiation scope.
2382  LocalInstantiationScope Scope(SemaRef);
2383  InstParams = SubstTemplateParams(TempParams);
2384  if (!InstParams)
2385  return nullptr;
2386  }
2387 
2388  // Build the template template parameter.
2389  TemplateTemplateParmDecl *Param;
2390  if (IsExpandedParameterPack)
2392  SemaRef.Context, Owner, D->getLocation(),
2393  D->getDepth() - TemplateArgs.getNumSubstitutedLevels(),
2394  D->getPosition(), D->getIdentifier(), InstParams, ExpandedParams);
2395  else
2397  SemaRef.Context, Owner, D->getLocation(),
2398  D->getDepth() - TemplateArgs.getNumSubstitutedLevels(),
2399  D->getPosition(), D->isParameterPack(), D->getIdentifier(), InstParams);
2400  if (D->hasDefaultArgument() && !D->defaultArgumentWasInherited()) {
2401  NestedNameSpecifierLoc QualifierLoc =
2403  QualifierLoc =
2404  SemaRef.SubstNestedNameSpecifierLoc(QualifierLoc, TemplateArgs);
2405  TemplateName TName = SemaRef.SubstTemplateName(
2406  QualifierLoc, D->getDefaultArgument().getArgument().getAsTemplate(),
2407  D->getDefaultArgument().getTemplateNameLoc(), TemplateArgs);
2408  if (!TName.isNull())
2409  Param->setDefaultArgument(
2410  SemaRef.Context,
2414  }
2415  Param->setAccess(AS_public);
2416 
2417  // Introduce this template parameter's instantiation into the instantiation
2418  // scope.
2419  SemaRef.CurrentInstantiationScope->InstantiatedLocal(D, Param);
2420 
2421  return Param;
2422 }
2423 
2424 Decl *TemplateDeclInstantiator::VisitUsingDirectiveDecl(UsingDirectiveDecl *D) {
2425  // Using directives are never dependent (and never contain any types or
2426  // expressions), so they require no explicit instantiation work.
2427 
2428  UsingDirectiveDecl *Inst
2429  = UsingDirectiveDecl::Create(SemaRef.Context, Owner, D->getLocation(),
2431  D->getQualifierLoc(),
2432  D->getIdentLocation(),
2433  D->getNominatedNamespace(),
2434  D->getCommonAncestor());
2435 
2436  // Add the using directive to its declaration context
2437  // only if this is not a function or method.
2438  if (!Owner->isFunctionOrMethod())
2439  Owner->addDecl(Inst);
2440 
2441  return Inst;
2442 }
2443 
2444 Decl *TemplateDeclInstantiator::VisitUsingDecl(UsingDecl *D) {
2445 
2446  // The nested name specifier may be dependent, for example
2447  // template <typename T> struct t {
2448  // struct s1 { T f1(); };
2449  // struct s2 : s1 { using s1::f1; };
2450  // };
2451  // template struct t<int>;
2452  // Here, in using s1::f1, s1 refers to t<T>::s1;
2453  // we need to substitute for t<int>::s1.
2454  NestedNameSpecifierLoc QualifierLoc
2456  TemplateArgs);
2457  if (!QualifierLoc)
2458  return nullptr;
2459 
2460  // For an inheriting constructor declaration, the name of the using
2461  // declaration is the name of a constructor in this class, not in the
2462  // base class.
2463  DeclarationNameInfo NameInfo = D->getNameInfo();
2465  if (auto *RD = dyn_cast<CXXRecordDecl>(SemaRef.CurContext))
2467  SemaRef.Context.getCanonicalType(SemaRef.Context.getRecordType(RD))));
2468 
2469  // We only need to do redeclaration lookups if we're in a class
2470  // scope (in fact, it's not really even possible in non-class
2471  // scopes).
2472  bool CheckRedeclaration = Owner->isRecord();
2473 
2474  LookupResult Prev(SemaRef, NameInfo, Sema::LookupUsingDeclName,
2476 
2477  UsingDecl *NewUD = UsingDecl::Create(SemaRef.Context, Owner,
2478  D->getUsingLoc(),
2479  QualifierLoc,
2480  NameInfo,
2481  D->hasTypename());
2482 
2483  CXXScopeSpec SS;
2484  SS.Adopt(QualifierLoc);
2485  if (CheckRedeclaration) {
2486  Prev.setHideTags(false);
2487  SemaRef.LookupQualifiedName(Prev, Owner);
2488 
2489  // Check for invalid redeclarations.
2490  if (SemaRef.CheckUsingDeclRedeclaration(D->getUsingLoc(),
2491  D->hasTypename(), SS,
2492  D->getLocation(), Prev))
2493  NewUD->setInvalidDecl();
2494 
2495  }
2496 
2497  if (!NewUD->isInvalidDecl() &&
2498  SemaRef.CheckUsingDeclQualifier(D->getUsingLoc(), D->hasTypename(),
2499  SS, NameInfo, D->getLocation()))
2500  NewUD->setInvalidDecl();
2501 
2502  SemaRef.Context.setInstantiatedFromUsingDecl(NewUD, D);
2503  NewUD->setAccess(D->getAccess());
2504  Owner->addDecl(NewUD);
2505 
2506  // Don't process the shadow decls for an invalid decl.
2507  if (NewUD->isInvalidDecl())
2508  return NewUD;
2509 
2510  if (NameInfo.getName().getNameKind() == DeclarationName::CXXConstructorName)
2511  SemaRef.CheckInheritingConstructorUsingDecl(NewUD);
2512 
2513  bool isFunctionScope = Owner->isFunctionOrMethod();
2514 
2515  // Process the shadow decls.
2516  for (auto *Shadow : D->shadows()) {
2517  // FIXME: UsingShadowDecl doesn't preserve its immediate target, so
2518  // reconstruct it in the case where it matters.
2519  NamedDecl *OldTarget = Shadow->getTargetDecl();
2520  if (auto *CUSD = dyn_cast<ConstructorUsingShadowDecl>(Shadow))
2521  if (auto *BaseShadow = CUSD->getNominatedBaseClassShadowDecl())
2522  OldTarget = BaseShadow;
2523 
2524  NamedDecl *InstTarget =
2525  cast_or_null<NamedDecl>(SemaRef.FindInstantiatedDecl(
2526  Shadow->getLocation(), OldTarget, TemplateArgs));
2527  if (!InstTarget)
2528  return nullptr;
2529 
2530  UsingShadowDecl *PrevDecl = nullptr;
2531  if (CheckRedeclaration) {
2532  if (SemaRef.CheckUsingShadowDecl(NewUD, InstTarget, Prev, PrevDecl))
2533  continue;
2534  } else if (UsingShadowDecl *OldPrev =
2536  PrevDecl = cast_or_null<UsingShadowDecl>(SemaRef.FindInstantiatedDecl(
2537  Shadow->getLocation(), OldPrev, TemplateArgs));
2538  }
2539 
2540  UsingShadowDecl *InstShadow =
2541  SemaRef.BuildUsingShadowDecl(/*Scope*/nullptr, NewUD, InstTarget,
2542  PrevDecl);
2543  SemaRef.Context.setInstantiatedFromUsingShadowDecl(InstShadow, Shadow);
2544 
2545  if (isFunctionScope)
2546  SemaRef.CurrentInstantiationScope->InstantiatedLocal(Shadow, InstShadow);
2547  }
2548 
2549  return NewUD;
2550 }
2551 
2552 Decl *TemplateDeclInstantiator::VisitUsingShadowDecl(UsingShadowDecl *D) {
2553  // Ignore these; we handle them in bulk when processing the UsingDecl.
2554  return nullptr;
2555 }
2556 
2557 Decl *TemplateDeclInstantiator::VisitConstructorUsingShadowDecl(
2559  // Ignore these; we handle them in bulk when processing the UsingDecl.
2560  return nullptr;
2561 }
2562 
2563 template <typename T>
2564 Decl *TemplateDeclInstantiator::instantiateUnresolvedUsingDecl(
2565  T *D, bool InstantiatingPackElement) {
2566  // If this is a pack expansion, expand it now.
2567  if (D->isPackExpansion() && !InstantiatingPackElement) {
2569  SemaRef.collectUnexpandedParameterPacks(D->getQualifierLoc(), Unexpanded);
2570  SemaRef.collectUnexpandedParameterPacks(D->getNameInfo(), Unexpanded);
2571 
2572  // Determine whether the set of unexpanded parameter packs can and should
2573  // be expanded.
2574  bool Expand = true;
2575  bool RetainExpansion = false;
2576  Optional<unsigned> NumExpansions;
2577  if (SemaRef.CheckParameterPacksForExpansion(
2578  D->getEllipsisLoc(), D->getSourceRange(), Unexpanded, TemplateArgs,
2579  Expand, RetainExpansion, NumExpansions))
2580  return nullptr;
2581 
2582  // This declaration cannot appear within a function template signature,
2583  // so we can't have a partial argument list for a parameter pack.
2584  assert(!RetainExpansion &&
2585  "should never need to retain an expansion for UsingPackDecl");
2586 
2587  if (!Expand) {
2588  // We cannot fully expand the pack expansion now, so substitute into the
2589  // pattern and create a new pack expansion.
2590  Sema::ArgumentPackSubstitutionIndexRAII SubstIndex(SemaRef, -1);
2591  return instantiateUnresolvedUsingDecl(D, true);
2592  }
2593 
2594  // Within a function, we don't have any normal way to check for conflicts
2595  // between shadow declarations from different using declarations in the
2596  // same pack expansion, but this is always ill-formed because all expansions
2597  // must produce (conflicting) enumerators.
2598  //
2599  // Sadly we can't just reject this in the template definition because it
2600  // could be valid if the pack is empty or has exactly one expansion.
2601  if (D->getDeclContext()->isFunctionOrMethod() && *NumExpansions > 1) {
2602  SemaRef.Diag(D->getEllipsisLoc(),
2603  diag::err_using_decl_redeclaration_expansion);
2604  return nullptr;
2605  }
2606 
2607  // Instantiate the slices of this pack and build a UsingPackDecl.
2608  SmallVector<NamedDecl*, 8> Expansions;
2609  for (unsigned I = 0; I != *NumExpansions; ++I) {
2610  Sema::ArgumentPackSubstitutionIndexRAII SubstIndex(SemaRef, I);
2611  Decl *Slice = instantiateUnresolvedUsingDecl(D, true);
2612  if (!Slice)
2613  return nullptr;
2614  // Note that we can still get unresolved using declarations here, if we
2615  // had arguments for all packs but the pattern also contained other
2616  // template arguments (this only happens during partial substitution, eg
2617  // into the body of a generic lambda in a function template).
2618  Expansions.push_back(cast<NamedDecl>(Slice));
2619  }
2620 
2621  auto *NewD = SemaRef.BuildUsingPackDecl(D, Expansions);
2622  if (isDeclWithinFunction(D))
2623  SemaRef.CurrentInstantiationScope->InstantiatedLocal(D, NewD);
2624  return NewD;
2625  }
2626 
2628  SourceLocation TypenameLoc = TD ? TD->getTypenameLoc() : SourceLocation();
2629 
2630  NestedNameSpecifierLoc QualifierLoc
2631  = SemaRef.SubstNestedNameSpecifierLoc(D->getQualifierLoc(),
2632  TemplateArgs);
2633  if (!QualifierLoc)
2634  return nullptr;
2635 
2636  CXXScopeSpec SS;
2637  SS.Adopt(QualifierLoc);
2638 
2639  DeclarationNameInfo NameInfo
2640  = SemaRef.SubstDeclarationNameInfo(D->getNameInfo(), TemplateArgs);
2641 
2642  // Produce a pack expansion only if we're not instantiating a particular
2643  // slice of a pack expansion.
2644  bool InstantiatingSlice = D->getEllipsisLoc().isValid() &&
2645  SemaRef.ArgumentPackSubstitutionIndex != -1;
2646  SourceLocation EllipsisLoc =
2647  InstantiatingSlice ? SourceLocation() : D->getEllipsisLoc();
2648 
2649  NamedDecl *UD = SemaRef.BuildUsingDeclaration(
2650  /*Scope*/ nullptr, D->getAccess(), D->getUsingLoc(),
2651  /*HasTypename*/ TD, TypenameLoc, SS, NameInfo, EllipsisLoc, nullptr,
2652  /*IsInstantiation*/ true);
2653  if (UD)
2654  SemaRef.Context.setInstantiatedFromUsingDecl(UD, D);
2655 
2656  return UD;
2657 }
2658 
2659 Decl *TemplateDeclInstantiator::VisitUnresolvedUsingTypenameDecl(
2661  return instantiateUnresolvedUsingDecl(D);
2662 }
2663 
2664 Decl *TemplateDeclInstantiator::VisitUnresolvedUsingValueDecl(
2666  return instantiateUnresolvedUsingDecl(D);
2667 }
2668 
2669 Decl *TemplateDeclInstantiator::VisitUsingPackDecl(UsingPackDecl *D) {
2670  SmallVector<NamedDecl*, 8> Expansions;
2671  for (auto *UD : D->expansions()) {
2672  if (NamedDecl *NewUD =
2673  SemaRef.FindInstantiatedDecl(D->getLocation(), UD, TemplateArgs))
2674  Expansions.push_back(NewUD);
2675  else
2676  return nullptr;
2677  }
2678 
2679  auto *NewD = SemaRef.BuildUsingPackDecl(D, Expansions);
2680  if (isDeclWithinFunction(D))
2681  SemaRef.CurrentInstantiationScope->InstantiatedLocal(D, NewD);
2682  return NewD;
2683 }
2684 
2685 Decl *TemplateDeclInstantiator::VisitClassScopeFunctionSpecializationDecl(
2687  CXXMethodDecl *OldFD = Decl->getSpecialization();
2688  CXXMethodDecl *NewFD =
2689  cast_or_null<CXXMethodDecl>(VisitCXXMethodDecl(OldFD, nullptr, true));
2690  if (!NewFD)
2691  return nullptr;
2692 
2695 
2696  TemplateArgumentListInfo TemplateArgs;
2697  TemplateArgumentListInfo *TemplateArgsPtr = nullptr;
2698  if (Decl->hasExplicitTemplateArgs()) {
2699  TemplateArgs = Decl->templateArgs();
2700  TemplateArgsPtr = &TemplateArgs;
2701  }
2702 
2703  SemaRef.LookupQualifiedName(Previous, SemaRef.CurContext);
2704  if (SemaRef.CheckFunctionTemplateSpecialization(NewFD, TemplateArgsPtr,
2705  Previous)) {
2706  NewFD->setInvalidDecl();
2707  return NewFD;
2708  }
2709 
2710  // Associate the specialization with the pattern.
2711  FunctionDecl *Specialization = cast<FunctionDecl>(Previous.getFoundDecl());
2712  assert(Specialization && "Class scope Specialization is null");
2713  SemaRef.Context.setClassScopeSpecializationPattern(Specialization, OldFD);
2714 
2715  // FIXME: If this is a definition, check for redefinition errors!
2716 
2717  return NewFD;
2718 }
2719 
2720 Decl *TemplateDeclInstantiator::VisitOMPThreadPrivateDecl(
2721  OMPThreadPrivateDecl *D) {
2723  for (auto *I : D->varlists()) {
2724  Expr *Var = SemaRef.SubstExpr(I, TemplateArgs).get();
2725  assert(isa<DeclRefExpr>(Var) && "threadprivate arg is not a DeclRefExpr");
2726  Vars.push_back(Var);
2727  }
2728 
2729  OMPThreadPrivateDecl *TD =
2730  SemaRef.CheckOMPThreadPrivateDecl(D->getLocation(), Vars);
2731 
2732  TD->setAccess(AS_public);
2733  Owner->addDecl(TD);
2734 
2735  return TD;
2736 }
2737 
2738 Decl *TemplateDeclInstantiator::VisitOMPDeclareReductionDecl(
2740  // Instantiate type and check if it is allowed.
2741  QualType SubstReductionType = SemaRef.ActOnOpenMPDeclareReductionType(
2742  D->getLocation(),
2743  ParsedType::make(SemaRef.SubstType(D->getType(), TemplateArgs,
2744  D->getLocation(), DeclarationName())));
2745  if (SubstReductionType.isNull())
2746  return nullptr;
2747  bool IsCorrect = !SubstReductionType.isNull();
2748  // Create instantiated copy.
2749  std::pair<QualType, SourceLocation> ReductionTypes[] = {
2750  std::make_pair(SubstReductionType, D->getLocation())};
2751  auto *PrevDeclInScope = D->getPrevDeclInScope();
2752  if (PrevDeclInScope && !PrevDeclInScope->isInvalidDecl()) {
2753  PrevDeclInScope = cast<OMPDeclareReductionDecl>(
2754  SemaRef.CurrentInstantiationScope->findInstantiationOf(PrevDeclInScope)
2755  ->get<Decl *>());
2756  }
2757  auto DRD = SemaRef.ActOnOpenMPDeclareReductionDirectiveStart(
2758  /*S=*/nullptr, Owner, D->getDeclName(), ReductionTypes, D->getAccess(),
2759  PrevDeclInScope);
2760  auto *NewDRD = cast<OMPDeclareReductionDecl>(DRD.get().getSingleDecl());
2761  if (isDeclWithinFunction(NewDRD))
2762  SemaRef.CurrentInstantiationScope->InstantiatedLocal(D, NewDRD);
2763  Expr *SubstCombiner = nullptr;
2764  Expr *SubstInitializer = nullptr;
2765  // Combiners instantiation sequence.
2766  if (D->getCombiner()) {
2768  /*S=*/nullptr, NewDRD);
2769  const char *Names[] = {"omp_in", "omp_out"};
2770  for (auto &Name : Names) {
2771  DeclarationName DN(&SemaRef.Context.Idents.get(Name));
2772  auto OldLookup = D->lookup(DN);
2773  auto Lookup = NewDRD->lookup(DN);
2774  if (!OldLookup.empty() && !Lookup.empty()) {
2775  assert(Lookup.size() == 1 && OldLookup.size() == 1);
2776  SemaRef.CurrentInstantiationScope->InstantiatedLocal(OldLookup.front(),
2777  Lookup.front());
2778  }
2779  }
2780  SubstCombiner = SemaRef.SubstExpr(D->getCombiner(), TemplateArgs).get();
2781  SemaRef.ActOnOpenMPDeclareReductionCombinerEnd(NewDRD, SubstCombiner);
2782  // Initializers instantiation sequence.
2783  if (D->getInitializer()) {
2784  VarDecl *OmpPrivParm =
2786  /*S=*/nullptr, NewDRD);
2787  const char *Names[] = {"omp_orig", "omp_priv"};
2788  for (auto &Name : Names) {
2789  DeclarationName DN(&SemaRef.Context.Idents.get(Name));
2790  auto OldLookup = D->lookup(DN);
2791  auto Lookup = NewDRD->lookup(DN);
2792  if (!OldLookup.empty() && !Lookup.empty()) {
2793  assert(Lookup.size() == 1 && OldLookup.size() == 1);
2794  auto *OldVD = cast<VarDecl>(OldLookup.front());
2795  auto *NewVD = cast<VarDecl>(Lookup.front());
2796  SemaRef.InstantiateVariableInitializer(NewVD, OldVD, TemplateArgs);
2797  SemaRef.CurrentInstantiationScope->InstantiatedLocal(OldVD, NewVD);
2798  }
2799  }
2801  SubstInitializer =
2802  SemaRef.SubstExpr(D->getInitializer(), TemplateArgs).get();
2803  } else {
2804  IsCorrect = IsCorrect && OmpPrivParm->hasInit();
2805  }
2807  NewDRD, SubstInitializer, OmpPrivParm);
2808  }
2809  IsCorrect =
2810  IsCorrect && SubstCombiner &&
2811  (!D->getInitializer() ||
2813  SubstInitializer) ||
2815  !SubstInitializer && !SubstInitializer));
2816  } else
2817  IsCorrect = false;
2818 
2819  (void)SemaRef.ActOnOpenMPDeclareReductionDirectiveEnd(/*S=*/nullptr, DRD,
2820  IsCorrect);
2821 
2822  return NewDRD;
2823 }
2824 
2825 Decl *TemplateDeclInstantiator::VisitOMPCapturedExprDecl(
2826  OMPCapturedExprDecl * /*D*/) {
2827  llvm_unreachable("Should not be met in templates");
2828 }
2829 
2831  return VisitFunctionDecl(D, nullptr);
2832 }
2833 
2834 Decl *
2835 TemplateDeclInstantiator::VisitCXXDeductionGuideDecl(CXXDeductionGuideDecl *D) {
2836  return VisitFunctionDecl(D, nullptr);
2837 }
2838 
2840  return VisitCXXMethodDecl(D, nullptr);
2841 }
2842 
2843 Decl *TemplateDeclInstantiator::VisitRecordDecl(RecordDecl *D) {
2844  llvm_unreachable("There are only CXXRecordDecls in C++");
2845 }
2846 
2847 Decl *
2848 TemplateDeclInstantiator::VisitClassTemplateSpecializationDecl(
2850  // As a MS extension, we permit class-scope explicit specialization
2851  // of member class templates.
2852  ClassTemplateDecl *ClassTemplate = D->getSpecializedTemplate();
2853  assert(ClassTemplate->getDeclContext()->isRecord() &&
2855  "can only instantiate an explicit specialization "
2856  "for a member class template");
2857 
2858  // Lookup the already-instantiated declaration in the instantiation
2859  // of the class template. FIXME: Diagnose or assert if this fails?
2861  = Owner->lookup(ClassTemplate->getDeclName());
2862  if (Found.empty())
2863  return nullptr;
2864  ClassTemplateDecl *InstClassTemplate
2865  = dyn_cast<ClassTemplateDecl>(Found.front());
2866  if (!InstClassTemplate)
2867  return nullptr;
2868 
2869  // Substitute into the template arguments of the class template explicit
2870  // specialization.
2872  castAs<TemplateSpecializationTypeLoc>();
2873  TemplateArgumentListInfo InstTemplateArgs(Loc.getLAngleLoc(),
2874  Loc.getRAngleLoc());
2876  for (unsigned I = 0; I != Loc.getNumArgs(); ++I)
2877  ArgLocs.push_back(Loc.getArgLoc(I));
2878  if (SemaRef.Subst(ArgLocs.data(), ArgLocs.size(),
2879  InstTemplateArgs, TemplateArgs))
2880  return nullptr;
2881 
2882  // Check that the template argument list is well-formed for this
2883  // class template.
2885  if (SemaRef.CheckTemplateArgumentList(InstClassTemplate,
2886  D->getLocation(),
2887  InstTemplateArgs,
2888  false,
2889  Converted))
2890  return nullptr;
2891 
2892  // Figure out where to insert this class template explicit specialization
2893  // in the member template's set of class template explicit specializations.
2894  void *InsertPos = nullptr;
2896  InstClassTemplate->findSpecialization(Converted, InsertPos);
2897 
2898  // Check whether we've already seen a conflicting instantiation of this
2899  // declaration (for instance, if there was a prior implicit instantiation).
2900  bool Ignored;
2901  if (PrevDecl &&
2903  D->getSpecializationKind(),
2904  PrevDecl,
2905  PrevDecl->getSpecializationKind(),
2906  PrevDecl->getPointOfInstantiation(),
2907  Ignored))
2908  return nullptr;
2909 
2910  // If PrevDecl was a definition and D is also a definition, diagnose.
2911  // This happens in cases like:
2912  //
2913  // template<typename T, typename U>
2914  // struct Outer {
2915  // template<typename X> struct Inner;
2916  // template<> struct Inner<T> {};
2917  // template<> struct Inner<U> {};
2918  // };
2919  //
2920  // Outer<int, int> outer; // error: the explicit specializations of Inner
2921  // // have the same signature.
2922  if (PrevDecl && PrevDecl->getDefinition() &&
2924  SemaRef.Diag(D->getLocation(), diag::err_redefinition) << PrevDecl;
2925  SemaRef.Diag(PrevDecl->getDefinition()->getLocation(),
2926  diag::note_previous_definition);
2927  return nullptr;
2928  }
2929 
2930  // Create the class template partial specialization declaration.
2933  D->getTagKind(),
2934  Owner,
2935  D->getLocStart(),
2936  D->getLocation(),
2937  InstClassTemplate,
2938  Converted,
2939  PrevDecl);
2940 
2941  // Add this partial specialization to the set of class template partial
2942  // specializations.
2943  if (!PrevDecl)
2944  InstClassTemplate->AddSpecialization(InstD, InsertPos);
2945 
2946  // Substitute the nested name specifier, if any.
2947  if (SubstQualifier(D, InstD))
2948  return nullptr;
2949 
2950  // Build the canonical type that describes the converted template
2951  // arguments of the class template explicit specialization.
2952  QualType CanonType = SemaRef.Context.getTemplateSpecializationType(
2953  TemplateName(InstClassTemplate), Converted,
2954  SemaRef.Context.getRecordType(InstD));
2955 
2956  // Build the fully-sugared type for this class template
2957  // specialization as the user wrote in the specialization
2958  // itself. This means that we'll pretty-print the type retrieved
2959  // from the specialization's declaration the way that the user
2960  // actually wrote the specialization, rather than formatting the
2961  // name based on the "canonical" representation used to store the
2962  // template arguments in the specialization.
2964  TemplateName(InstClassTemplate), D->getLocation(), InstTemplateArgs,
2965  CanonType);
2966 
2967  InstD->setAccess(D->getAccess());
2970  InstD->setTypeAsWritten(WrittenTy);
2971  InstD->setExternLoc(D->getExternLoc());
2973 
2974  Owner->addDecl(InstD);
2975 
2976  // Instantiate the members of the class-scope explicit specialization eagerly.
2977  // We don't have support for lazy instantiation of an explicit specialization
2978  // yet, and MSVC eagerly instantiates in this case.
2979  if (D->isThisDeclarationADefinition() &&
2980  SemaRef.InstantiateClass(D->getLocation(), InstD, D, TemplateArgs,
2982  /*Complain=*/true))
2983  return nullptr;
2984 
2985  return InstD;
2986 }
2987 
2990 
2991  TemplateArgumentListInfo VarTemplateArgsInfo;
2992  VarTemplateDecl *VarTemplate = D->getSpecializedTemplate();
2993  assert(VarTemplate &&
2994  "A template specialization without specialized template?");
2995 
2996  // Substitute the current template arguments.
2997  const TemplateArgumentListInfo &TemplateArgsInfo = D->getTemplateArgsInfo();
2998  VarTemplateArgsInfo.setLAngleLoc(TemplateArgsInfo.getLAngleLoc());
2999  VarTemplateArgsInfo.setRAngleLoc(TemplateArgsInfo.getRAngleLoc());
3000 
3001  if (SemaRef.Subst(TemplateArgsInfo.getArgumentArray(),
3002  TemplateArgsInfo.size(), VarTemplateArgsInfo, TemplateArgs))
3003  return nullptr;
3004 
3005  // Check that the template argument list is well-formed for this template.
3007  if (SemaRef.CheckTemplateArgumentList(
3008  VarTemplate, VarTemplate->getLocStart(),
3009  const_cast<TemplateArgumentListInfo &>(VarTemplateArgsInfo), false,
3010  Converted))
3011  return nullptr;
3012 
3013  // Find the variable template specialization declaration that
3014  // corresponds to these arguments.
3015  void *InsertPos = nullptr;
3016  if (VarTemplateSpecializationDecl *VarSpec = VarTemplate->findSpecialization(
3017  Converted, InsertPos))
3018  // If we already have a variable template specialization, return it.
3019  return VarSpec;
3020 
3021  return VisitVarTemplateSpecializationDecl(VarTemplate, D, InsertPos,
3022  VarTemplateArgsInfo, Converted);
3023 }
3024 
3026  VarTemplateDecl *VarTemplate, VarDecl *D, void *InsertPos,
3027  const TemplateArgumentListInfo &TemplateArgsInfo,
3028  ArrayRef<TemplateArgument> Converted) {
3029 
3030  // Do substitution on the type of the declaration
3031  TypeSourceInfo *DI =
3032  SemaRef.SubstType(D->getTypeSourceInfo(), TemplateArgs,
3033  D->getTypeSpecStartLoc(), D->getDeclName());
3034  if (!DI)
3035  return nullptr;
3036 
3037  if (DI->getType()->isFunctionType()) {
3038  SemaRef.Diag(D->getLocation(), diag::err_variable_instantiates_to_function)
3039  << D->isStaticDataMember() << DI->getType();
3040  return nullptr;
3041  }
3042 
3043  // Build the instantiated declaration
3045  SemaRef.Context, Owner, D->getInnerLocStart(), D->getLocation(),
3046  VarTemplate, DI->getType(), DI, D->getStorageClass(), Converted);
3047  Var->setTemplateArgsInfo(TemplateArgsInfo);
3048  if (InsertPos)
3049  VarTemplate->AddSpecialization(Var, InsertPos);
3050 
3051  // Substitute the nested name specifier, if any.
3052  if (SubstQualifier(D, Var))
3053  return nullptr;
3054 
3055  SemaRef.BuildVariableInstantiation(Var, D, TemplateArgs, LateAttrs,
3056  Owner, StartingScope);
3057 
3058  return Var;
3059 }
3060 
3061 Decl *TemplateDeclInstantiator::VisitObjCAtDefsFieldDecl(ObjCAtDefsFieldDecl *D) {
3062  llvm_unreachable("@defs is not supported in Objective-C++");
3063 }
3064 
3065 Decl *TemplateDeclInstantiator::VisitFriendTemplateDecl(FriendTemplateDecl *D) {
3066  // FIXME: We need to be able to instantiate FriendTemplateDecls.
3067  unsigned DiagID = SemaRef.getDiagnostics().getCustomDiagID(
3069  "cannot instantiate %0 yet");
3070  SemaRef.Diag(D->getLocation(), DiagID)
3071  << D->getDeclKindName();
3072 
3073  return nullptr;
3074 }
3075 
3077  llvm_unreachable("Unexpected decl");
3078 }
3079 
3080 Decl *Sema::SubstDecl(Decl *D, DeclContext *Owner,
3081  const MultiLevelTemplateArgumentList &TemplateArgs) {
3082  TemplateDeclInstantiator Instantiator(*this, Owner, TemplateArgs);
3083  if (D->isInvalidDecl())
3084  return nullptr;
3085 
3086  return Instantiator.Visit(D);
3087 }
3088 
3089 /// Instantiates a nested template parameter list in the current
3090 /// instantiation context.
3091 ///
3092 /// \param L The parameter list to instantiate
3093 ///
3094 /// \returns NULL if there was an error
3097  // Get errors for all the parameters before bailing out.
3098  bool Invalid = false;
3099 
3100  unsigned N = L->size();
3101  typedef SmallVector<NamedDecl *, 8> ParamVector;
3102  ParamVector Params;
3103  Params.reserve(N);
3104  for (auto &P : *L) {
3105  NamedDecl *D = cast_or_null<NamedDecl>(Visit(P));
3106  Params.push_back(D);
3107  Invalid = Invalid || !D || D->isInvalidDecl();
3108  }
3109 
3110  // Clean up if we had an error.
3111  if (Invalid)
3112  return nullptr;
3113 
3114  // Note: we substitute into associated constraints later
3115  Expr *const UninstantiatedRequiresClause = L->getRequiresClause();
3116 
3117  TemplateParameterList *InstL
3118  = TemplateParameterList::Create(SemaRef.Context, L->getTemplateLoc(),
3119  L->getLAngleLoc(), Params,
3120  L->getRAngleLoc(),
3121  UninstantiatedRequiresClause);
3122  return InstL;
3123 }
3124 
3127  const MultiLevelTemplateArgumentList &TemplateArgs) {
3128  TemplateDeclInstantiator Instantiator(*this, Owner, TemplateArgs);
3129  return Instantiator.SubstTemplateParams(Params);
3130 }
3131 
3132 /// Instantiate the declaration of a class template partial
3133 /// specialization.
3134 ///
3135 /// \param ClassTemplate the (instantiated) class template that is partially
3136 // specialized by the instantiation of \p PartialSpec.
3137 ///
3138 /// \param PartialSpec the (uninstantiated) class template partial
3139 /// specialization that we are instantiating.
3140 ///
3141 /// \returns The instantiated partial specialization, if successful; otherwise,
3142 /// NULL to indicate an error.
3145  ClassTemplateDecl *ClassTemplate,
3147  // Create a local instantiation scope for this class template partial
3148  // specialization, which will contain the instantiations of the template
3149  // parameters.
3150  LocalInstantiationScope Scope(SemaRef);
3151 
3152  // Substitute into the template parameters of the class template partial
3153  // specialization.
3154  TemplateParameterList *TempParams = PartialSpec->getTemplateParameters();
3155  TemplateParameterList *InstParams = SubstTemplateParams(TempParams);
3156  if (!InstParams)
3157  return nullptr;
3158 
3159  // Substitute into the template arguments of the class template partial
3160  // specialization.
3161  const ASTTemplateArgumentListInfo *TemplArgInfo
3162  = PartialSpec->getTemplateArgsAsWritten();
3163  TemplateArgumentListInfo InstTemplateArgs(TemplArgInfo->LAngleLoc,
3164  TemplArgInfo->RAngleLoc);
3165  if (SemaRef.Subst(TemplArgInfo->getTemplateArgs(),
3166  TemplArgInfo->NumTemplateArgs,
3167  InstTemplateArgs, TemplateArgs))
3168  return nullptr;
3169 
3170  // Check that the template argument list is well-formed for this
3171  // class template.
3173  if (SemaRef.CheckTemplateArgumentList(ClassTemplate,
3174  PartialSpec->getLocation(),
3175  InstTemplateArgs,
3176  false,
3177  Converted))
3178  return nullptr;
3179 
3180  // Check these arguments are valid for a template partial specialization.
3182  PartialSpec->getLocation(), ClassTemplate, InstTemplateArgs.size(),
3183  Converted))
3184  return nullptr;
3185 
3186  // Figure out where to insert this class template partial specialization
3187  // in the member template's set of class template partial specializations.
3188  void *InsertPos = nullptr;
3190  = ClassTemplate->findPartialSpecialization(Converted, InsertPos);
3191 
3192  // Build the canonical type that describes the converted template
3193  // arguments of the class template partial specialization.
3194  QualType CanonType
3195  = SemaRef.Context.getTemplateSpecializationType(TemplateName(ClassTemplate),
3196  Converted);
3197 
3198  // Build the fully-sugared type for this class template
3199  // specialization as the user wrote in the specialization
3200  // itself. This means that we'll pretty-print the type retrieved
3201  // from the specialization's declaration the way that the user
3202  // actually wrote the specialization, rather than formatting the
3203  // name based on the "canonical" representation used to store the
3204  // template arguments in the specialization.
3205  TypeSourceInfo *WrittenTy
3207  TemplateName(ClassTemplate),
3208  PartialSpec->getLocation(),
3209  InstTemplateArgs,
3210  CanonType);
3211 
3212  if (PrevDecl) {
3213  // We've already seen a partial specialization with the same template
3214  // parameters and template arguments. This can happen, for example, when
3215  // substituting the outer template arguments ends up causing two
3216  // class template partial specializations of a member class template
3217  // to have identical forms, e.g.,
3218  //
3219  // template<typename T, typename U>
3220  // struct Outer {
3221  // template<typename X, typename Y> struct Inner;
3222  // template<typename Y> struct Inner<T, Y>;
3223  // template<typename Y> struct Inner<U, Y>;
3224  // };
3225  //
3226  // Outer<int, int> outer; // error: the partial specializations of Inner
3227  // // have the same signature.
3228  SemaRef.Diag(PartialSpec->getLocation(), diag::err_partial_spec_redeclared)
3229  << WrittenTy->getType();
3230  SemaRef.Diag(PrevDecl->getLocation(), diag::note_prev_partial_spec_here)
3231  << SemaRef.Context.getTypeDeclType(PrevDecl);
3232  return nullptr;
3233  }
3234 
3235 
3236  // Create the class template partial specialization declaration.
3239  PartialSpec->getTagKind(),
3240  Owner,
3241  PartialSpec->getLocStart(),
3242  PartialSpec->getLocation(),
3243  InstParams,
3244  ClassTemplate,
3245  Converted,
3246  InstTemplateArgs,
3247  CanonType,
3248  nullptr);
3249  // Substitute the nested name specifier, if any.
3250  if (SubstQualifier(PartialSpec, InstPartialSpec))
3251  return nullptr;
3252 
3253  InstPartialSpec->setInstantiatedFromMember(PartialSpec);
3254  InstPartialSpec->setTypeAsWritten(WrittenTy);
3255 
3256  // Check the completed partial specialization.
3257  SemaRef.CheckTemplatePartialSpecialization(InstPartialSpec);
3258 
3259  // Add this partial specialization to the set of class template partial
3260  // specializations.
3261  ClassTemplate->AddPartialSpecialization(InstPartialSpec,
3262  /*InsertPos=*/nullptr);
3263  return InstPartialSpec;
3264 }
3265 
3266 /// Instantiate the declaration of a variable template partial
3267 /// specialization.
3268 ///
3269 /// \param VarTemplate the (instantiated) variable template that is partially
3270 /// specialized by the instantiation of \p PartialSpec.
3271 ///
3272 /// \param PartialSpec the (uninstantiated) variable template partial
3273 /// specialization that we are instantiating.
3274 ///
3275 /// \returns The instantiated partial specialization, if successful; otherwise,
3276 /// NULL to indicate an error.
3279  VarTemplateDecl *VarTemplate,
3280  VarTemplatePartialSpecializationDecl *PartialSpec) {
3281  // Create a local instantiation scope for this variable template partial
3282  // specialization, which will contain the instantiations of the template
3283  // parameters.
3284  LocalInstantiationScope Scope(SemaRef);
3285 
3286  // Substitute into the template parameters of the variable template partial
3287  // specialization.
3288  TemplateParameterList *TempParams = PartialSpec->getTemplateParameters();
3289  TemplateParameterList *InstParams = SubstTemplateParams(TempParams);
3290  if (!InstParams)
3291  return nullptr;
3292 
3293  // Substitute into the template arguments of the variable template partial
3294  // specialization.
3295  const ASTTemplateArgumentListInfo *TemplArgInfo
3296  = PartialSpec->getTemplateArgsAsWritten();
3297  TemplateArgumentListInfo InstTemplateArgs(TemplArgInfo->LAngleLoc,
3298  TemplArgInfo->RAngleLoc);
3299  if (SemaRef.Subst(TemplArgInfo->getTemplateArgs(),
3300  TemplArgInfo->NumTemplateArgs,
3301  InstTemplateArgs, TemplateArgs))
3302  return nullptr;
3303 
3304  // Check that the template argument list is well-formed for this
3305  // class template.
3307  if (SemaRef.CheckTemplateArgumentList(VarTemplate, PartialSpec->getLocation(),
3308  InstTemplateArgs, false, Converted))
3309  return nullptr;
3310 
3311  // Check these arguments are valid for a template partial specialization.
3313  PartialSpec->getLocation(), VarTemplate, InstTemplateArgs.size(),
3314  Converted))
3315  return nullptr;
3316 
3317  // Figure out where to insert this variable template partial specialization
3318  // in the member template's set of variable template partial specializations.
3319  void *InsertPos = nullptr;
3320  VarTemplateSpecializationDecl *PrevDecl =
3321  VarTemplate->findPartialSpecialization(Converted, InsertPos);
3322 
3323  // Build the canonical type that describes the converted template
3324  // arguments of the variable template partial specialization.
3325  QualType CanonType = SemaRef.Context.getTemplateSpecializationType(
3326  TemplateName(VarTemplate), Converted);
3327 
3328  // Build the fully-sugared type for this variable template
3329  // specialization as the user wrote in the specialization
3330  // itself. This means that we'll pretty-print the type retrieved
3331  // from the specialization's declaration the way that the user
3332  // actually wrote the specialization, rather than formatting the
3333  // name based on the "canonical" representation used to store the
3334  // template arguments in the specialization.
3336  TemplateName(VarTemplate), PartialSpec->getLocation(), InstTemplateArgs,
3337  CanonType);
3338 
3339  if (PrevDecl) {
3340  // We've already seen a partial specialization with the same template
3341  // parameters and template arguments. This can happen, for example, when
3342  // substituting the outer template arguments ends up causing two
3343  // variable template partial specializations of a member variable template
3344  // to have identical forms, e.g.,
3345  //
3346  // template<typename T, typename U>
3347  // struct Outer {
3348  // template<typename X, typename Y> pair<X,Y> p;
3349  // template<typename Y> pair<T, Y> p;
3350  // template<typename Y> pair<U, Y> p;
3351  // };
3352  //
3353  // Outer<int, int> outer; // error: the partial specializations of Inner
3354  // // have the same signature.
3355  SemaRef.Diag(PartialSpec->getLocation(),
3356  diag::err_var_partial_spec_redeclared)
3357  << WrittenTy->getType();
3358  SemaRef.Diag(PrevDecl->getLocation(),
3359  diag::note_var_prev_partial_spec_here);
3360  return nullptr;
3361  }
3362 
3363  // Do substitution on the type of the declaration
3364  TypeSourceInfo *DI = SemaRef.SubstType(
3365  PartialSpec->getTypeSourceInfo(), TemplateArgs,
3366  PartialSpec->getTypeSpecStartLoc(), PartialSpec->getDeclName());
3367  if (!DI)
3368  return nullptr;
3369 
3370  if (DI->getType()->isFunctionType()) {
3371  SemaRef.Diag(PartialSpec->getLocation(),
3372  diag::err_variable_instantiates_to_function)
3373  << PartialSpec->isStaticDataMember() << DI->getType();
3374  return nullptr;
3375  }
3376 
3377  // Create the variable template partial specialization declaration.
3378  VarTemplatePartialSpecializationDecl *InstPartialSpec =
3380  SemaRef.Context, Owner, PartialSpec->getInnerLocStart(),
3381  PartialSpec->getLocation(), InstParams, VarTemplate, DI->getType(),
3382  DI, PartialSpec->getStorageClass(), Converted, InstTemplateArgs);
3383 
3384  // Substitute the nested name specifier, if any.
3385  if (SubstQualifier(PartialSpec, InstPartialSpec))
3386  return nullptr;
3387 
3388  InstPartialSpec->setInstantiatedFromMember(PartialSpec);
3389  InstPartialSpec->setTypeAsWritten(WrittenTy);
3390 
3391  // Check the completed partial specialization.
3392  SemaRef.CheckTemplatePartialSpecialization(InstPartialSpec);
3393 
3394  // Add this partial specialization to the set of variable template partial
3395  // specializations. The instantiation of the initializer is not necessary.
3396  VarTemplate->AddPartialSpecialization(InstPartialSpec, /*InsertPos=*/nullptr);
3397 
3398  SemaRef.BuildVariableInstantiation(InstPartialSpec, PartialSpec, TemplateArgs,
3399  LateAttrs, Owner, StartingScope);
3400 
3401  return InstPartialSpec;
3402 }
3403 
3407  TypeSourceInfo *OldTInfo = D->getTypeSourceInfo();
3408  assert(OldTInfo && "substituting function without type source info");
3409  assert(Params.empty() && "parameter vector is non-empty at start");
3410 
3411  CXXRecordDecl *ThisContext = nullptr;
3412  unsigned ThisTypeQuals = 0;
3413  if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(D)) {
3414  ThisContext = cast<CXXRecordDecl>(Owner);
3415  ThisTypeQuals = Method->getTypeQualifiers();
3416  }
3417 
3418  TypeSourceInfo *NewTInfo
3419  = SemaRef.SubstFunctionDeclType(OldTInfo, TemplateArgs,
3420  D->getTypeSpecStartLoc(),
3421  D->getDeclName(),
3422  ThisContext, ThisTypeQuals);
3423  if (!NewTInfo)
3424  return nullptr;
3425 
3426  TypeLoc OldTL = OldTInfo->getTypeLoc().IgnoreParens();
3427  if (FunctionProtoTypeLoc OldProtoLoc = OldTL.getAs<FunctionProtoTypeLoc>()) {
3428  if (NewTInfo != OldTInfo) {
3429  // Get parameters from the new type info.
3430  TypeLoc NewTL = NewTInfo->getTypeLoc().IgnoreParens();
3431  FunctionProtoTypeLoc NewProtoLoc = NewTL.castAs<FunctionProtoTypeLoc>();
3432  unsigned NewIdx = 0;
3433  for (unsigned OldIdx = 0, NumOldParams = OldProtoLoc.getNumParams();
3434  OldIdx != NumOldParams; ++OldIdx) {
3435  ParmVarDecl *OldParam = OldProtoLoc.getParam(OldIdx);
3437 
3438  Optional<unsigned> NumArgumentsInExpansion;
3439  if (OldParam->isParameterPack())
3440  NumArgumentsInExpansion =
3441  SemaRef.getNumArgumentsInExpansion(OldParam->getType(),
3442  TemplateArgs);
3443  if (!NumArgumentsInExpansion) {
3444  // Simple case: normal parameter, or a parameter pack that's
3445  // instantiated to a (still-dependent) parameter pack.
3446  ParmVarDecl *NewParam = NewProtoLoc.getParam(NewIdx++);
3447  Params.push_back(NewParam);
3448  Scope->InstantiatedLocal(OldParam, NewParam);
3449  } else {
3450  // Parameter pack expansion: make the instantiation an argument pack.
3451  Scope->MakeInstantiatedLocalArgPack(OldParam);
3452  for (unsigned I = 0; I != *NumArgumentsInExpansion; ++I) {
3453  ParmVarDecl *NewParam = NewProtoLoc.getParam(NewIdx++);
3454  Params.push_back(NewParam);
3455  Scope->InstantiatedLocalPackArg(OldParam, NewParam);
3456  }
3457  }
3458  }
3459  } else {
3460  // The function type itself was not dependent and therefore no
3461  // substitution occurred. However, we still need to instantiate
3462  // the function parameters themselves.
3463  const FunctionProtoType *OldProto =
3464  cast<FunctionProtoType>(OldProtoLoc.getType());
3465  for (unsigned i = 0, i_end = OldProtoLoc.getNumParams(); i != i_end;
3466  ++i) {
3467  ParmVarDecl *OldParam = OldProtoLoc.getParam(i);
3468  if (!OldParam) {
3469  Params.push_back(SemaRef.BuildParmVarDeclForTypedef(
3470  D, D->getLocation(), OldProto->getParamType(i)));
3471  continue;
3472  }
3473 
3474  ParmVarDecl *Parm =
3475  cast_or_null<ParmVarDecl>(VisitParmVarDecl(OldParam));
3476  if (!Parm)
3477  return nullptr;
3478  Params.push_back(Parm);
3479  }
3480  }
3481  } else {
3482  // If the type of this function, after ignoring parentheses, is not
3483  // *directly* a function type, then we're instantiating a function that
3484  // was declared via a typedef or with attributes, e.g.,
3485  //
3486  // typedef int functype(int, int);
3487  // functype func;
3488  // int __cdecl meth(int, int);
3489  //
3490  // In this case, we'll just go instantiate the ParmVarDecls that we
3491  // synthesized in the method declaration.
3492  SmallVector<QualType, 4> ParamTypes;
3493  Sema::ExtParameterInfoBuilder ExtParamInfos;
3494  if (SemaRef.SubstParmTypes(D->getLocation(), D->parameters(), nullptr,
3495  TemplateArgs, ParamTypes, &Params,
3496  ExtParamInfos))
3497  return nullptr;
3498  }
3499 
3500  return NewTInfo;
3501 }
3502 
3503 /// Introduce the instantiated function parameters into the local
3504 /// instantiation scope, and set the parameter names to those used
3505 /// in the template.
3507  const FunctionDecl *PatternDecl,
3509  const MultiLevelTemplateArgumentList &TemplateArgs) {
3510  unsigned FParamIdx = 0;
3511  for (unsigned I = 0, N = PatternDecl->getNumParams(); I != N; ++I) {
3512  const ParmVarDecl *PatternParam = PatternDecl->getParamDecl(I);
3513  if (!PatternParam->isParameterPack()) {
3514  // Simple case: not a parameter pack.
3515  assert(FParamIdx < Function->getNumParams());
3516  ParmVarDecl *FunctionParam = Function->getParamDecl(FParamIdx);
3517  FunctionParam->setDeclName(PatternParam->getDeclName());
3518  // If the parameter's type is not dependent, update it to match the type
3519  // in the pattern. They can differ in top-level cv-qualifiers, and we want
3520  // the pattern's type here. If the type is dependent, they can't differ,
3521  // per core issue 1668. Substitute into the type from the pattern, in case
3522  // it's instantiation-dependent.
3523  // FIXME: Updating the type to work around this is at best fragile.
3524  if (!PatternDecl->getType()->isDependentType()) {
3525  QualType T = S.SubstType(PatternParam->getType(), TemplateArgs,
3526  FunctionParam->getLocation(),
3527  FunctionParam->getDeclName());
3528  if (T.isNull())
3529  return true;
3530  FunctionParam->setType(T);
3531  }
3532 
3533  Scope.InstantiatedLocal(PatternParam, FunctionParam);
3534  ++FParamIdx;
3535  continue;
3536  }
3537 
3538  // Expand the parameter pack.
3539  Scope.MakeInstantiatedLocalArgPack(PatternParam);
3540  Optional<unsigned> NumArgumentsInExpansion
3541  = S.getNumArgumentsInExpansion(PatternParam->getType(), TemplateArgs);
3542  assert(NumArgumentsInExpansion &&
3543  "should only be called when all template arguments are known");
3544  QualType PatternType =
3545  PatternParam->getType()->castAs<PackExpansionType>()->getPattern();
3546  for (unsigned Arg = 0; Arg < *NumArgumentsInExpansion; ++Arg) {
3547  ParmVarDecl *FunctionParam = Function->getParamDecl(FParamIdx);
3548  FunctionParam->setDeclName(PatternParam->getDeclName());
3549  if (!PatternDecl->getType()->isDependentType()) {
3550  Sema::ArgumentPackSubstitutionIndexRAII SubstIndex(S, Arg);
3551  QualType T = S.SubstType(PatternType, TemplateArgs,
3552  FunctionParam->getLocation(),
3553  FunctionParam->getDeclName());
3554  if (T.isNull())
3555  return true;
3556  FunctionParam->setType(T);
3557  }
3558 
3559  Scope.InstantiatedLocalPackArg(PatternParam, FunctionParam);
3560  ++FParamIdx;
3561  }
3562  }
3563 
3564  return false;
3565 }
3566 
3568  FunctionDecl *Decl) {
3569  const FunctionProtoType *Proto = Decl->getType()->castAs<FunctionProtoType>();
3570  if (Proto->getExceptionSpecType() != EST_Uninstantiated)
3571  return;
3572 
3573  InstantiatingTemplate Inst(*this, PointOfInstantiation, Decl,
3575  if (Inst.isInvalid()) {
3576  // We hit the instantiation depth limit. Clear the exception specification
3577  // so that our callers don't have to cope with EST_Uninstantiated.
3578  UpdateExceptionSpec(Decl, EST_None);
3579  return;
3580  }
3581  if (Inst.isAlreadyInstantiating()) {
3582  // This exception specification indirectly depends on itself. Reject.
3583  // FIXME: Corresponding rule in the standard?
3584  Diag(PointOfInstantiation, diag::err_exception_spec_cycle) << Decl;
3585  UpdateExceptionSpec(Decl, EST_None);
3586  return;
3587  }
3588 
3589  // Enter the scope of this instantiation. We don't use
3590  // PushDeclContext because we don't have a scope.
3591  Sema::ContextRAII savedContext(*this, Decl);
3593 
3594  MultiLevelTemplateArgumentList TemplateArgs =
3595  getTemplateInstantiationArgs(Decl, nullptr, /*RelativeToPrimary*/true);
3596 
3597  FunctionDecl *Template = Proto->getExceptionSpecTemplate();
3598  if (addInstantiatedParametersToScope(*this, Decl, Template, Scope,
3599  TemplateArgs)) {
3600  UpdateExceptionSpec(Decl, EST_None);
3601  return;
3602  }
3603 
3604  SubstExceptionSpec(Decl, Template->getType()->castAs<FunctionProtoType>(),
3605  TemplateArgs);
3606 }
3607 
3608 /// Initializes the common fields of an instantiation function
3609 /// declaration (New) from the corresponding fields of its template (Tmpl).
3610 ///
3611 /// \returns true if there was an error
3612 bool
3614  FunctionDecl *Tmpl) {
3615  if (Tmpl->isDeleted())
3616  New->setDeletedAsWritten();
3617 
3618  New->setImplicit(Tmpl->isImplicit());
3619 
3620  // Forward the mangling number from the template to the instantiated decl.
3621  SemaRef.Context.setManglingNumber(New,
3622  SemaRef.Context.getManglingNumber(Tmpl));
3623 
3624  // If we are performing substituting explicitly-specified template arguments
3625  // or deduced template arguments into a function template and we reach this
3626  // point, we are now past the point where SFINAE applies and have committed
3627  // to keeping the new function template specialization. We therefore
3628  // convert the active template instantiation for the function template
3629  // into a template instantiation for this specific function template
3630  // specialization, which is not a SFINAE context, so that we diagnose any
3631  // further errors in the declaration itself.
3632  typedef Sema::CodeSynthesisContext ActiveInstType;
3633  ActiveInstType &ActiveInst = SemaRef.CodeSynthesisContexts.back();
3634  if (ActiveInst.Kind == ActiveInstType::ExplicitTemplateArgumentSubstitution ||
3635  ActiveInst.Kind == ActiveInstType::DeducedTemplateArgumentSubstitution) {
3636  if (FunctionTemplateDecl *FunTmpl
3637  = dyn_cast<FunctionTemplateDecl>(ActiveInst.Entity)) {
3638  assert(FunTmpl->getTemplatedDecl() == Tmpl &&
3639  "Deduction from the wrong function template?");
3640  (void) FunTmpl;
3641  atTemplateEnd(SemaRef.TemplateInstCallbacks, SemaRef, ActiveInst);
3642  ActiveInst.Kind = ActiveInstType::TemplateInstantiation;
3643  ActiveInst.Entity = New;
3644  atTemplateBegin(SemaRef.TemplateInstCallbacks, SemaRef, ActiveInst);
3645  }
3646  }
3647 
3648  const FunctionProtoType *Proto = Tmpl->getType()->getAs<FunctionProtoType>();
3649  assert(Proto && "Function template without prototype?");
3650 
3651  if (Proto->hasExceptionSpec() || Proto->getNoReturnAttr()) {
3653 
3654  // DR1330: In C++11, defer instantiation of a non-trivial
3655  // exception specification.
3656  // DR1484: Local classes and their members are instantiated along with the
3657  // containing function.
3658  if (SemaRef.getLangOpts().CPlusPlus11 &&
3659  EPI.ExceptionSpec.Type != EST_None &&
3663  FunctionDecl *ExceptionSpecTemplate = Tmpl;
3665  ExceptionSpecTemplate = EPI.ExceptionSpec.SourceTemplate;
3667  if (EPI.ExceptionSpec.Type == EST_Unevaluated)
3668  NewEST = EST_Unevaluated;
3669 
3670  // Mark the function has having an uninstantiated exception specification.
3671  const FunctionProtoType *NewProto
3672  = New->getType()->getAs<FunctionProtoType>();
3673  assert(NewProto && "Template instantiation without function prototype?");
3674  EPI = NewProto->getExtProtoInfo();
3675  EPI.ExceptionSpec.Type = NewEST;
3676  EPI.ExceptionSpec.SourceDecl = New;
3677  EPI.ExceptionSpec.SourceTemplate = ExceptionSpecTemplate;
3678  New->setType(SemaRef.Context.getFunctionType(
3679  NewProto->getReturnType(), NewProto->getParamTypes(), EPI));
3680  } else {
3681  Sema::ContextRAII SwitchContext(SemaRef, New);
3682  SemaRef.SubstExceptionSpec(New, Proto, TemplateArgs);
3683  }
3684  }
3685 
3686  // Get the definition. Leaves the variable unchanged if undefined.
3687  const FunctionDecl *Definition = Tmpl;
3688  Tmpl->isDefined(Definition);
3689 
3690  SemaRef.InstantiateAttrs(TemplateArgs, Definition, New,
3691  LateAttrs, StartingScope);
3692 
3693  return false;
3694 }
3695 
3696 /// Initializes common fields of an instantiated method
3697 /// declaration (New) from the corresponding fields of its template
3698 /// (Tmpl).
3699 ///
3700 /// \returns true if there was an error
3701 bool
3703  CXXMethodDecl *Tmpl) {
3704  if (InitFunctionInstantiation(New, Tmpl))
3705  return true;
3706 
3707  New->setAccess(Tmpl->getAccess());
3708  if (Tmpl->isVirtualAsWritten())
3709  New->setVirtualAsWritten(true);
3710 
3711  // FIXME: New needs a pointer to Tmpl
3712  return false;
3713 }
3714 
3715 /// Instantiate (or find existing instantiation of) a function template with a
3716 /// given set of template arguments.
3717 ///
3718 /// Usually this should not be used, and template argument deduction should be
3719 /// used in its place.
3720 FunctionDecl *
3722  const TemplateArgumentList *Args,
3723  SourceLocation Loc) {
3724  FunctionDecl *FD = FTD->getTemplatedDecl();
3725 
3726  sema::TemplateDeductionInfo Info(Loc);
3727  InstantiatingTemplate Inst(
3728  *this, Loc, FTD, Args->asArray(),
3729  CodeSynthesisContext::ExplicitTemplateArgumentSubstitution, Info);
3730  if (Inst.isInvalid())
3731  return nullptr;
3732 
3733  ContextRAII SavedContext(*this, FD);
3734  MultiLevelTemplateArgumentList MArgs(*Args);
3735 
3736  return cast_or_null<FunctionDecl>(SubstDecl(FD, FD->getParent(), MArgs));
3737 }
3738 
3739 /// In the MS ABI, we need to instantiate default arguments of dllexported
3740 /// default constructors along with the constructor definition. This allows IR
3741 /// gen to emit a constructor closure which calls the default constructor with
3742 /// its default arguments.
3744  CXXConstructorDecl *Ctor) {
3745  assert(S.Context.getTargetInfo().getCXXABI().isMicrosoft() &&
3746  Ctor->isDefaultConstructor());
3747  unsigned NumParams = Ctor->getNumParams();
3748  if (NumParams == 0)
3749  return;
3750  DLLExportAttr *Attr = Ctor->getAttr<DLLExportAttr>();
3751  if (!Attr)
3752  return;
3753  for (unsigned I = 0; I != NumParams; ++I) {
3754  (void)S.CheckCXXDefaultArgExpr(Attr->getLocation(), Ctor,
3755  Ctor->getParamDecl(I));
3757  }
3758 }
3759 
3760 /// Instantiate the definition of the given function from its
3761 /// template.
3762 ///
3763 /// \param PointOfInstantiation the point at which the instantiation was
3764 /// required. Note that this is not precisely a "point of instantiation"
3765 /// for the function, but it's close.
3766 ///
3767 /// \param Function the already-instantiated declaration of a
3768 /// function template specialization or member function of a class template
3769 /// specialization.
3770 ///
3771 /// \param Recursive if true, recursively instantiates any functions that
3772 /// are required by this instantiation.
3773 ///
3774 /// \param DefinitionRequired if true, then we are performing an explicit
3775 /// instantiation where the body of the function is required. Complain if
3776 /// there is no such body.
3778  FunctionDecl *Function,
3779  bool Recursive,
3780  bool DefinitionRequired,
3781  bool AtEndOfTU) {
3782  if (Function->isInvalidDecl() || Function->isDefined() ||
3783  isa<CXXDeductionGuideDecl>(Function))
3784  return;
3785 
3786  // Never instantiate an explicit specialization except if it is a class scope
3787  // explicit specialization.
3789  if (TSK == TSK_ExplicitSpecialization &&
3791  return;
3792 
3793  // Find the function body that we'll be substituting.
3794  const FunctionDecl *PatternDecl = Function->getTemplateInstantiationPattern();
3795  assert(PatternDecl && "instantiating a non-template");
3796 
3797  const FunctionDecl *PatternDef = PatternDecl->getDefinition();
3798  Stmt *Pattern = nullptr;
3799  if (PatternDef) {
3800  Pattern = PatternDef->getBody(PatternDef);
3801  PatternDecl = PatternDef;
3802  if (PatternDef->willHaveBody())
3803  PatternDef = nullptr;
3804  }
3805 
3806  // FIXME: We need to track the instantiation stack in order to know which
3807  // definitions should be visible within this instantiation.
3808  if (DiagnoseUninstantiableTemplate(PointOfInstantiation, Function,
3810  PatternDecl, PatternDef, TSK,
3811  /*Complain*/DefinitionRequired)) {
3812  if (DefinitionRequired)
3813  Function->setInvalidDecl();
3814  else if (TSK == TSK_ExplicitInstantiationDefinition) {
3815  // Try again at the end of the translation unit (at which point a
3816  // definition will be required).
3817  assert(!Recursive);
3818  Function->setInstantiationIsPending(true);
3819  PendingInstantiations.push_back(
3820  std::make_pair(Function, PointOfInstantiation));
3821  } else if (TSK == TSK_ImplicitInstantiation) {
3822  if (AtEndOfTU && !getDiagnostics().hasErrorOccurred() &&
3823  !getSourceManager().isInSystemHeader(PatternDecl->getLocStart())) {
3824  Diag(PointOfInstantiation, diag::warn_func_template_missing)
3825  << Function;
3826  Diag(PatternDecl->getLocation(), diag::note_forward_template_decl);
3827  if (getLangOpts().CPlusPlus11)
3828  Diag(PointOfInstantiation, diag::note_inst_declaration_hint)
3829  << Function;
3830  }
3831  }
3832 
3833  return;
3834  }
3835 
3836  // Postpone late parsed template instantiations.
3837  if (PatternDecl->isLateTemplateParsed() &&
3838  !LateTemplateParser) {
3839  Function->setInstantiationIsPending(true);
3840  LateParsedInstantiations.push_back(
3841  std::make_pair(Function, PointOfInstantiation));
3842  return;
3843  }
3844 
3845  // If we're performing recursive template instantiation, create our own
3846  // queue of pending implicit instantiations that we will instantiate later,
3847  // while we're still within our own instantiation context.
3848  // This has to happen before LateTemplateParser below is called, so that
3849  // it marks vtables used in late parsed templates as used.
3850  GlobalEagerInstantiationScope GlobalInstantiations(*this,
3851  /*Enabled=*/Recursive);
3852  LocalEagerInstantiationScope LocalInstantiations(*this);
3853 
3854  // Call the LateTemplateParser callback if there is a need to late parse
3855  // a templated function definition.
3856  if (!Pattern && PatternDecl->isLateTemplateParsed() &&
3857  LateTemplateParser) {
3858  // FIXME: Optimize to allow individual templates to be deserialized.
3859  if (PatternDecl->isFromASTFile())
3860  ExternalSource->ReadLateParsedTemplates(LateParsedTemplateMap);
3861 
3862  auto LPTIter = LateParsedTemplateMap.find(PatternDecl);
3863  assert(LPTIter != LateParsedTemplateMap.end() &&
3864  "missing LateParsedTemplate");
3865  LateTemplateParser(OpaqueParser, *LPTIter->second);
3866  Pattern = PatternDecl->getBody(PatternDecl);
3867  }
3868 
3869  // Note, we should never try to instantiate a deleted function template.
3870  assert((Pattern || PatternDecl->isDefaulted() ||
3871  PatternDecl->hasSkippedBody()) &&
3872  "unexpected kind of function template definition");
3873 
3874  // C++1y [temp.explicit]p10:
3875  // Except for inline functions, declarations with types deduced from their
3876  // initializer or return value, and class template specializations, other
3877  // explicit instantiation declarations have the effect of suppressing the
3878  // implicit instantiation of the entity to which they refer.
3880  !PatternDecl->isInlined() &&
3881  !PatternDecl->getReturnType()->getContainedAutoType())
3882  return;
3883 
3884  if (PatternDecl->isInlined()) {
3885  // Function, and all later redeclarations of it (from imported modules,
3886  // for instance), are now implicitly inline.
3887  for (auto *D = Function->getMostRecentDecl(); /**/;
3888  D = D->getPreviousDecl()) {
3889  D->setImplicitlyInline();
3890  if (D == Function)
3891  break;
3892  }
3893  }
3894 
3895  InstantiatingTemplate Inst(*this, PointOfInstantiation, Function);
3896  if (Inst.isInvalid() || Inst.isAlreadyInstantiating())
3897  return;
3898  PrettyDeclStackTraceEntry CrashInfo(Context, Function, SourceLocation(),
3899  "instantiating function definition");
3900 
3901  // The instantiation is visible here, even if it was first declared in an
3902  // unimported module.
3903  Function->setVisibleDespiteOwningModule();
3904 
3905  // Copy the inner loc start from the pattern.
3906  Function->setInnerLocStart(PatternDecl->getInnerLocStart());
3907 
3910 
3911  // Introduce a new scope where local variable instantiations will be
3912  // recorded, unless we're actually a member function within a local
3913  // class, in which case we need to merge our results with the parent
3914  // scope (of the enclosing function).
3915  bool MergeWithParentScope = false;
3916  if (CXXRecordDecl *Rec = dyn_cast<CXXRecordDecl>(Function->getDeclContext()))
3917  MergeWithParentScope = Rec->isLocalClass();
3918 
3919  LocalInstantiationScope Scope(*this, MergeWithParentScope);
3920 
3921  if (PatternDecl->isDefaulted())
3922  SetDeclDefaulted(Function, PatternDecl->getLocation());
3923  else {
3924  MultiLevelTemplateArgumentList TemplateArgs =
3925  getTemplateInstantiationArgs(Function, nullptr, false, PatternDecl);
3926 
3927  // Substitute into the qualifier; we can get a substitution failure here
3928  // through evil use of alias templates.
3929  // FIXME: Is CurContext correct for this? Should we go to the (instantiation
3930  // of the) lexical context of the pattern?
3931  SubstQualifier(*this, PatternDecl, Function, TemplateArgs);
3932 
3933  ActOnStartOfFunctionDef(nullptr, Function);
3934 
3935  // Enter the scope of this instantiation. We don't use
3936  // PushDeclContext because we don't have a scope.
3937  Sema::ContextRAII savedContext(*this, Function);
3938 
3939  if (addInstantiatedParametersToScope(*this, Function, PatternDecl, Scope,
3940  TemplateArgs))
3941  return;
3942 
3943  StmtResult Body;
3944  if (PatternDecl->hasSkippedBody()) {
3945  ActOnSkippedFunctionBody(Function);
3946  Body = nullptr;
3947  } else {
3948  if (CXXConstructorDecl *Ctor = dyn_cast<CXXConstructorDecl>(Function)) {
3949  // If this is a constructor, instantiate the member initializers.
3950  InstantiateMemInitializers(Ctor, cast<CXXConstructorDecl>(PatternDecl),
3951  TemplateArgs);
3952 
3953  // If this is an MS ABI dllexport default constructor, instantiate any
3954  // default arguments.
3955  if (Context.getTargetInfo().getCXXABI().isMicrosoft() &&
3956  Ctor->isDefaultConstructor()) {
3957  InstantiateDefaultCtorDefaultArgs(*this, Ctor);
3958  }
3959  }
3960 
3961  // Instantiate the function body.
3962  Body = SubstStmt(Pattern, TemplateArgs);
3963 
3964  if (Body.isInvalid())
3965  Function->setInvalidDecl();
3966  }
3967  // FIXME: finishing the function body while in an expression evaluation
3968  // context seems wrong. Investigate more.
3969  ActOnFinishFunctionBody(Function, Body.get(), /*IsInstantiation=*/true);
3970 
3971  PerformDependentDiagnostics(PatternDecl, TemplateArgs);
3972 
3973  if (auto *Listener = getASTMutationListener())
3974  Listener->FunctionDefinitionInstantiated(Function);
3975 
3976  savedContext.pop();
3977  }
3978 
3979  DeclGroupRef DG(Function);
3980  Consumer.HandleTopLevelDecl(DG);
3981 
3982  // This class may have local implicit instantiations that need to be
3983  // instantiation within this scope.
3984  LocalInstantiations.perform();
3985  Scope.Exit();
3986  GlobalInstantiations.perform();
3987 }
3988 
3990  VarTemplateDecl *VarTemplate, VarDecl *FromVar,
3991  const TemplateArgumentList &TemplateArgList,
3992  const TemplateArgumentListInfo &TemplateArgsInfo,
3994  SourceLocation PointOfInstantiation, void *InsertPos,
3995  LateInstantiatedAttrVec *LateAttrs,
3996  LocalInstantiationScope *StartingScope) {
3997  if (FromVar->isInvalidDecl())
3998  return nullptr;
3999 
4000  InstantiatingTemplate Inst(*this, PointOfInstantiation, FromVar);
4001  if (Inst.isInvalid())
4002  return nullptr;
4003 
4004  MultiLevelTemplateArgumentList TemplateArgLists;
4005  TemplateArgLists.addOuterTemplateArguments(&TemplateArgList);
4006 
4007  // Instantiate the first declaration of the variable template: for a partial
4008  // specialization of a static data member template, the first declaration may
4009  // or may not be the declaration in the class; if it's in the class, we want
4010  // to instantiate a member in the class (a declaration), and if it's outside,
4011  // we want to instantiate a definition.
4012  //
4013  // If we're instantiating an explicitly-specialized member template or member
4014  // partial specialization, don't do this. The member specialization completely
4015  // replaces the original declaration in this case.
4016  bool IsMemberSpec = false;
4017  if (VarTemplatePartialSpecializationDecl *PartialSpec =
4018  dyn_cast<VarTemplatePartialSpecializationDecl>(FromVar))
4019  IsMemberSpec = PartialSpec->isMemberSpecialization();
4020  else if (VarTemplateDecl *FromTemplate = FromVar->getDescribedVarTemplate())
4021  IsMemberSpec = FromTemplate->isMemberSpecialization();
4022  if (!IsMemberSpec)
4023  FromVar = FromVar->getFirstDecl();
4024 
4025  MultiLevelTemplateArgumentList MultiLevelList(TemplateArgList);
4026  TemplateDeclInstantiator Instantiator(*this, FromVar->getDeclContext(),
4027  MultiLevelList);
4028 
4029  // TODO: Set LateAttrs and StartingScope ...
4030 
4031  return cast_or_null<VarTemplateSpecializationDecl>(
4032  Instantiator.VisitVarTemplateSpecializationDecl(
4033  VarTemplate, FromVar, InsertPos, TemplateArgsInfo, Converted));
4034 }
4035 
4036 /// Instantiates a variable template specialization by completing it
4037 /// with appropriate type information and initializer.
4039  VarTemplateSpecializationDecl *VarSpec, VarDecl *PatternDecl,
4040  const MultiLevelTemplateArgumentList &TemplateArgs) {
4041  assert(PatternDecl->isThisDeclarationADefinition() &&
4042  "don't have a definition to instantiate from");
4043 
4044  // Do substitution on the type of the declaration
4045  TypeSourceInfo *DI =
4046  SubstType(PatternDecl->getTypeSourceInfo(), TemplateArgs,
4047  PatternDecl->getTypeSpecStartLoc(), PatternDecl->getDeclName());
4048  if (!DI)
4049  return nullptr;
4050 
4051  // Update the type of this variable template specialization.
4052  VarSpec->setType(DI->getType());
4053 
4054  // Convert the declaration into a definition now.
4055  VarSpec->setCompleteDefinition();
4056 
4057  // Instantiate the initializer.
4058  InstantiateVariableInitializer(VarSpec, PatternDecl, TemplateArgs);
4059 
4060  return VarSpec;
4061 }
4062 
4063 /// BuildVariableInstantiation - Used after a new variable has been created.
4064 /// Sets basic variable data and decides whether to postpone the
4065 /// variable instantiation.
4067  VarDecl *NewVar, VarDecl *OldVar,
4068  const MultiLevelTemplateArgumentList &TemplateArgs,
4069  LateInstantiatedAttrVec *LateAttrs, DeclContext *Owner,
4070  LocalInstantiationScope *StartingScope,
4071  bool InstantiatingVarTemplate) {
4072 
4073  // If we are instantiating a local extern declaration, the
4074  // instantiation belongs lexically to the containing function.
4075  // If we are instantiating a static data member defined
4076  // out-of-line, the instantiation will have the same lexical
4077  // context (which will be a namespace scope) as the template.
4078  if (OldVar->isLocalExternDecl()) {
4079  NewVar->setLocalExternDecl();
4080  NewVar->setLexicalDeclContext(Owner);
4081  } else if (OldVar->isOutOfLine())
4082  NewVar->setLexicalDeclContext(OldVar->getLexicalDeclContext());
4083  NewVar->setTSCSpec(OldVar->getTSCSpec());
4084  NewVar->setInitStyle(OldVar->getInitStyle());
4085  NewVar->setCXXForRangeDecl(OldVar->isCXXForRangeDecl());
4086  NewVar->setObjCForDecl(OldVar->isObjCForDecl());
4087  NewVar->setConstexpr(OldVar->isConstexpr());
4088  NewVar->setInitCapture(OldVar->isInitCapture());
4090  OldVar->isPreviousDeclInSameBlockScope());
4091  NewVar->setAccess(OldVar->getAccess());
4092 
4093  if (!OldVar->isStaticDataMember()) {
4094  if (OldVar->isUsed(false))
4095  NewVar->setIsUsed();
4096  NewVar->setReferenced(OldVar->isReferenced());
4097  }
4098 
4099  InstantiateAttrs(TemplateArgs, OldVar, NewVar, LateAttrs, StartingScope);
4100 
4102  *this, NewVar->getDeclName(), NewVar->getLocation(),
4106  : forRedeclarationInCurContext());
4107 
4108  if (NewVar->isLocalExternDecl() && OldVar->getPreviousDecl() &&
4110  OldVar->getPreviousDecl()->getDeclContext()==OldVar->getDeclContext())) {
4111  // We have a previous declaration. Use that one, so we merge with the
4112  // right type.
4113  if (NamedDecl *NewPrev = FindInstantiatedDecl(
4114  NewVar->getLocation(), OldVar->getPreviousDecl(), TemplateArgs))
4115  Previous.addDecl(NewPrev);
4116  } else if (!isa<VarTemplateSpecializationDecl>(NewVar) &&
4117  OldVar->hasLinkage())
4118  LookupQualifiedName(Previous, NewVar->getDeclContext(), false);
4119  CheckVariableDeclaration(NewVar, Previous);
4120 
4121  if (!InstantiatingVarTemplate) {
4122  NewVar->getLexicalDeclContext()->addHiddenDecl(NewVar);
4123  if (!NewVar->isLocalExternDecl() || !NewVar->getPreviousDecl())
4124  NewVar->getDeclContext()->makeDeclVisibleInContext(NewVar);
4125  }
4126 
4127  if (!OldVar->isOutOfLine()) {
4128  if (NewVar->getDeclContext()->isFunctionOrMethod())
4129  CurrentInstantiationScope->InstantiatedLocal(OldVar, NewVar);
4130  }
4131 
4132  // Link instantiations of static data members back to the template from
4133  // which they were instantiated.
4134  if (NewVar->isStaticDataMember() && !InstantiatingVarTemplate)
4135  NewVar->setInstantiationOfStaticDataMember(OldVar,
4137 
4138  // Forward the mangling number from the template to the instantiated decl.
4139  Context.setManglingNumber(NewVar, Context.getManglingNumber(OldVar));
4140  Context.setStaticLocalNumber(NewVar, Context.getStaticLocalNumber(OldVar));
4141 
4142  // Delay instantiation of the initializer for variable templates or inline
4143  // static data members until a definition of the variable is needed. We need
4144  // it right away if the type contains 'auto'.
4145  if ((!isa<VarTemplateSpecializationDecl>(NewVar) &&
4146  !InstantiatingVarTemplate &&
4147  !(OldVar->isInline() && OldVar->isThisDeclarationADefinition() &&
4148  !NewVar->isThisDeclarationADefinition())) ||
4149  NewVar->getType()->isUndeducedType())
4150  InstantiateVariableInitializer(NewVar, OldVar, TemplateArgs);
4151 
4152  // Diagnose unused local variables with dependent types, where the diagnostic
4153  // will have been deferred.
4154  if (!NewVar->isInvalidDecl() &&
4155  NewVar->getDeclContext()->isFunctionOrMethod() &&
4156  OldVar->getType()->isDependentType())
4157  DiagnoseUnusedDecl(NewVar);
4158 }
4159 
4160 /// Instantiate the initializer of a variable.
4162  VarDecl *Var, VarDecl *OldVar,
4163  const MultiLevelTemplateArgumentList &TemplateArgs) {
4164  if (ASTMutationListener *L = getASTContext().getASTMutationListener())
4165  L->VariableDefinitionInstantiated(Var);
4166 
4167  // We propagate the 'inline' flag with the initializer, because it
4168  // would otherwise imply that the variable is a definition for a
4169  // non-static data member.
4170  if (OldVar->isInlineSpecified())
4171  Var->setInlineSpecified();
4172  else if (OldVar->isInline())
4173  Var->setImplicitlyInline();
4174 
4175  if (OldVar->getInit()) {
4178 
4179  // Instantiate the initializer.
4180  ExprResult Init;
4181 
4182  {
4183  ContextRAII SwitchContext(*this, Var->getDeclContext());
4184  Init = SubstInitializer(OldVar->getInit(), TemplateArgs,
4185  OldVar->getInitStyle() == VarDecl::CallInit);
4186  }
4187 
4188  if (!Init.isInvalid()) {
4189  Expr *InitExpr = Init.get();
4190 
4191  if (Var->hasAttr<DLLImportAttr>() &&
4192  (!InitExpr ||
4193  !InitExpr->isConstantInitializer(getASTContext(), false))) {
4194  // Do not dynamically initialize dllimport variables.
4195  } else if (InitExpr) {
4196  bool DirectInit = OldVar->isDirectInit();
4197  AddInitializerToDecl(Var, InitExpr, DirectInit);
4198  } else
4199  ActOnUninitializedDecl(Var);
4200  } else {
4201  // FIXME: Not too happy about invalidating the declaration
4202  // because of a bogus initializer.
4203  Var->setInvalidDecl();
4204  }
4205  } else {
4206  // `inline` variables are a definition and declaration all in one; we won't
4207  // pick up an initializer from anywhere else.
4208  if (Var->isStaticDataMember() && !Var->isInline()) {
4209  if (!Var->isOutOfLine())
4210  return;
4211 
4212  // If the declaration inside the class had an initializer, don't add
4213  // another one to the out-of-line definition.
4214  if (OldVar->getFirstDecl()->hasInit())
4215  return;
4216  }
4217 
4218  // We'll add an initializer to a for-range declaration later.
4219  if (Var->isCXXForRangeDecl() || Var->isObjCForDecl())
4220  return;
4221 
4222  ActOnUninitializedDecl(Var);
4223  }
4224 }
4225 
4226 /// Instantiate the definition of the given variable from its
4227 /// template.
4228 ///
4229 /// \param PointOfInstantiation the point at which the instantiation was
4230 /// required. Note that this is not precisely a "point of instantiation"
4231 /// for the variable, but it's close.
4232 ///
4233 /// \param Var the already-instantiated declaration of a templated variable.
4234 ///
4235 /// \param Recursive if true, recursively instantiates any functions that
4236 /// are required by this instantiation.
4237 ///
4238 /// \param DefinitionRequired if true, then we are performing an explicit
4239 /// instantiation where a definition of the variable is required. Complain
4240 /// if there is no such definition.
4242  VarDecl *Var, bool Recursive,
4243  bool DefinitionRequired, bool AtEndOfTU) {
4244  if (Var->isInvalidDecl())
4245  return;
4246 
4248  dyn_cast<VarTemplateSpecializationDecl>(Var);
4249  VarDecl *PatternDecl = nullptr, *Def = nullptr;
4250  MultiLevelTemplateArgumentList TemplateArgs =
4251  getTemplateInstantiationArgs(Var);
4252 
4253  if (VarSpec) {
4254  // If this is a variable template specialization, make sure that it is
4255  // non-dependent, then find its instantiation pattern.
4256  bool InstantiationDependent = false;
4258  VarSpec->getTemplateArgsInfo(), InstantiationDependent) &&
4259  "Only instantiate variable template specializations that are "
4260  "not type-dependent");
4261  (void)InstantiationDependent;
4262 
4263  // Find the variable initialization that we'll be substituting. If the
4264  // pattern was instantiated from a member template, look back further to
4265  // find the real pattern.
4266  assert(VarSpec->getSpecializedTemplate() &&
4267  "Specialization without specialized template?");
4268  llvm::PointerUnion<VarTemplateDecl *,
4269  VarTemplatePartialSpecializationDecl *> PatternPtr =
4271  if (PatternPtr.is<VarTemplatePartialSpecializationDecl *>()) {
4273  PatternPtr.get<VarTemplatePartialSpecializationDecl *>();
4275  Tmpl->getInstantiatedFromMember()) {
4276  if (Tmpl->isMemberSpecialization())
4277  break;
4278 
4279  Tmpl = From;
4280  }
4281  PatternDecl = Tmpl;
4282  } else {
4283  VarTemplateDecl *Tmpl = PatternPtr.get<VarTemplateDecl *>();
4284  while (VarTemplateDecl *From =
4286  if (Tmpl->isMemberSpecialization())
4287  break;
4288 
4289  Tmpl = From;
4290  }
4291  PatternDecl = Tmpl->getTemplatedDecl();
4292  }
4293 
4294  // If this is a static data member template, there might be an
4295  // uninstantiated initializer on the declaration. If so, instantiate
4296  // it now.
4297  //
4298  // FIXME: This largely duplicates what we would do below. The difference
4299  // is that along this path we may instantiate an initializer from an
4300  // in-class declaration of the template and instantiate the definition
4301  // from a separate out-of-class definition.
4302  if (PatternDecl->isStaticDataMember() &&
4303  (PatternDecl = PatternDecl->getFirstDecl())->hasInit() &&
4304  !Var->hasInit()) {
4305  // FIXME: Factor out the duplicated instantiation context setup/tear down
4306  // code here.
4307  InstantiatingTemplate Inst(*this, PointOfInstantiation, Var);
4308  if (Inst.isInvalid() || Inst.isAlreadyInstantiating())
4309  return;
4310  PrettyDeclStackTraceEntry CrashInfo(Context, Var, SourceLocation(),
4311  "instantiating variable initializer");
4312 
4313  // The instantiation is visible here, even if it was first declared in an
4314  // unimported module.
4316 
4317  // If we're performing recursive template instantiation, create our own
4318  // queue of pending implicit instantiations that we will instantiate
4319  // later, while we're still within our own instantiation context.
4320  GlobalEagerInstantiationScope GlobalInstantiations(*this,
4321  /*Enabled=*/Recursive);
4322  LocalInstantiationScope Local(*this);
4323  LocalEagerInstantiationScope LocalInstantiations(*this);
4324 
4325  // Enter the scope of this instantiation. We don't use
4326  // PushDeclContext because we don't have a scope.
4327  ContextRAII PreviousContext(*this, Var->getDeclContext());
4328  InstantiateVariableInitializer(Var, PatternDecl, TemplateArgs);
4329  PreviousContext.pop();
4330 
4331  // This variable may have local implicit instantiations that need to be
4332  // instantiated within this scope.
4333  LocalInstantiations.perform();
4334  Local.Exit();
4335  GlobalInstantiations.perform();
4336  }
4337 
4338  // Find actual definition
4339  Def = PatternDecl->getDefinition(getASTContext());
4340  } else {
4341  // If this is a static data member, find its out-of-line definition.
4342  assert(Var->isStaticDataMember() && "not a static data member?");
4343  PatternDecl = Var->getInstantiatedFromStaticDataMember();
4344 
4345  assert(PatternDecl && "data member was not instantiated from a template?");
4346  assert(PatternDecl->isStaticDataMember() && "not a static data member?");
4347  Def = PatternDecl->getDefinition();
4348  }
4349 
4351 
4352  // If we don't have a definition of the variable template, we won't perform
4353  // any instantiation. Rather, we rely on the user to instantiate this
4354  // definition (or provide a specialization for it) in another translation
4355  // unit.
4356  if (!Def && !DefinitionRequired) {
4358  PendingInstantiations.push_back(
4359  std::make_pair(Var, PointOfInstantiation));
4360  } else if (TSK == TSK_ImplicitInstantiation) {
4361  // Warn about missing definition at the end of translation unit.
4362  if (AtEndOfTU && !getDiagnostics().hasErrorOccurred() &&
4363  !getSourceManager().isInSystemHeader(PatternDecl->getLocStart())) {
4364  Diag(PointOfInstantiation, diag::warn_var_template_missing)
4365  << Var;
4366  Diag(PatternDecl->getLocation(), diag::note_forward_template_decl);
4367  if (getLangOpts().CPlusPlus11)
4368  Diag(PointOfInstantiation, diag::note_inst_declaration_hint) << Var;
4369  }
4370  return;
4371  }
4372 
4373  }
4374 
4375  // FIXME: We need to track the instantiation stack in order to know which
4376  // definitions should be visible within this instantiation.
4377  // FIXME: Produce diagnostics when Var->getInstantiatedFromStaticDataMember().
4378  if (DiagnoseUninstantiableTemplate(PointOfInstantiation, Var,
4379  /*InstantiatedFromMember*/false,
4380  PatternDecl, Def, TSK,
4381  /*Complain*/DefinitionRequired))
4382  return;
4383 
4384 
4385  // Never instantiate an explicit specialization.
4386  if (TSK == TSK_ExplicitSpecialization)
4387  return;
4388 
4389  // C++11 [temp.explicit]p10:
4390  // Except for inline functions, const variables of literal types, variables
4391  // of reference types, [...] explicit instantiation declarations
4392  // have the effect of suppressing the implicit instantiation of the entity
4393  // to which they refer.
4395  !Var->isUsableInConstantExpressions(getASTContext()))
4396  return;
4397 
4398  // Make sure to pass the instantiated variable to the consumer at the end.
4399  struct PassToConsumerRAII {
4400  ASTConsumer &Consumer;
4401  VarDecl *Var;
4402 
4403  PassToConsumerRAII(ASTConsumer &Consumer, VarDecl *Var)
4404  : Consumer(Consumer), Var(Var) { }
4405 
4406  ~PassToConsumerRAII() {
4408  }
4409  } PassToConsumerRAII(Consumer, Var);
4410 
4411  // If we already have a definition, we're done.
4412  if (VarDecl *Def = Var->getDefinition()) {
4413  // We may be explicitly instantiating something we've already implicitly
4414  // instantiated.
4415  Def->setTemplateSpecializationKind(Var->getTemplateSpecializationKind(),
4416  PointOfInstantiation);
4417  return;
4418  }
4419 
4420  InstantiatingTemplate Inst(*this, PointOfInstantiation, Var);
4421  if (Inst.isInvalid() || Inst.isAlreadyInstantiating())
4422  return;
4423  PrettyDeclStackTraceEntry CrashInfo(Context, Var, SourceLocation(),
4424  "instantiating variable definition");
4425 
4426  // If we're performing recursive template instantiation, create our own
4427  // queue of pending implicit instantiations that we will instantiate later,
4428  // while we're still within our own instantiation context.
4429  GlobalEagerInstantiationScope GlobalInstantiations(*this,
4430  /*Enabled=*/Recursive);
4431 
4432  // Enter the scope of this instantiation. We don't use
4433  // PushDeclContext because we don't have a scope.
4434  ContextRAII PreviousContext(*this, Var->getDeclContext());
4435  LocalInstantiationScope Local(*this);
4436 
4437  LocalEagerInstantiationScope LocalInstantiations(*this);
4438 
4439  VarDecl *OldVar = Var;
4440  if (Def->isStaticDataMember() && !Def->isOutOfLine()) {
4441  // We're instantiating an inline static data member whose definition was
4442  // provided inside the class.
4443  InstantiateVariableInitializer(Var, Def, TemplateArgs);
4444  } else if (!VarSpec) {
4445  Var = cast_or_null<VarDecl>(SubstDecl(Def, Var->getDeclContext(),
4446  TemplateArgs));
4447  } else if (Var->isStaticDataMember() &&
4448  Var->getLexicalDeclContext()->isRecord()) {
4449  // We need to instantiate the definition of a static data member template,
4450  // and all we have is the in-class declaration of it. Instantiate a separate
4451  // declaration of the definition.
4452  TemplateDeclInstantiator Instantiator(*this, Var->getDeclContext(),
4453  TemplateArgs);
4454  Var = cast_or_null<VarDecl>(Instantiator.VisitVarTemplateSpecializationDecl(
4455  VarSpec->getSpecializedTemplate(), Def, nullptr,
4456  VarSpec->getTemplateArgsInfo(), VarSpec->getTemplateArgs().asArray()));
4457  if (Var) {
4458  llvm::PointerUnion<VarTemplateDecl *,
4459  VarTemplatePartialSpecializationDecl *> PatternPtr =
4462  PatternPtr.dyn_cast<VarTemplatePartialSpecializationDecl *>())
4463  cast<VarTemplateSpecializationDecl>(Var)->setInstantiationOf(
4464  Partial, &VarSpec->getTemplateInstantiationArgs());
4465 
4466  // Merge the definition with the declaration.
4467  LookupResult R(*this, Var->getDeclName(), Var->getLocation(),
4468  LookupOrdinaryName, forRedeclarationInCurContext());
4469  R.addDecl(OldVar);
4470  MergeVarDecl(Var, R);
4471 
4472  // Attach the initializer.
4473  InstantiateVariableInitializer(Var, Def, TemplateArgs);
4474  }
4475  } else
4476  // Complete the existing variable's definition with an appropriately
4477  // substituted type and initializer.
4478  Var = CompleteVarTemplateSpecializationDecl(VarSpec, Def, TemplateArgs);
4479 
4480  PreviousContext.pop();
4481 
4482  if (Var) {
4483  PassToConsumerRAII.Var = Var;
4485  OldVar->getPointOfInstantiation());
4486  }
4487 
4488  // This variable may have local implicit instantiations that need to be
4489  // instantiated within this scope.
4490  LocalInstantiations.perform();
4491  Local.Exit();
4492  GlobalInstantiations.perform();
4493 }
4494 
4495 void
4497  const CXXConstructorDecl *Tmpl,
4498  const MultiLevelTemplateArgumentList &TemplateArgs) {
4499 
4501  bool AnyErrors = Tmpl->isInvalidDecl();
4502 
4503  // Instantiate all the initializers.
4504  for (const auto *Init : Tmpl->inits()) {
4505  // Only instantiate written initializers, let Sema re-construct implicit
4506  // ones.
4507  if (!Init->isWritten())
4508  continue;
4509 
4510  SourceLocation EllipsisLoc;
4511 
4512  if (Init->isPackExpansion()) {
4513  // This is a pack expansion. We should expand it now.
4514  TypeLoc BaseTL = Init->getTypeSourceInfo()->getTypeLoc();
4516  collectUnexpandedParameterPacks(BaseTL, Unexpanded);
4517  collectUnexpandedParameterPacks(Init->getInit(), Unexpanded);
4518  bool ShouldExpand = false;
4519  bool RetainExpansion = false;
4520  Optional<unsigned> NumExpansions;
4521  if (CheckParameterPacksForExpansion(Init->getEllipsisLoc(),
4522  BaseTL.getSourceRange(),
4523  Unexpanded,
4524  TemplateArgs, ShouldExpand,
4525  RetainExpansion,
4526  NumExpansions)) {
4527  AnyErrors = true;
4528  New->setInvalidDecl();
4529  continue;
4530  }
4531  assert(ShouldExpand && "Partial instantiation of base initializer?");
4532 
4533  // Loop over all of the arguments in the argument pack(s),
4534  for (unsigned I = 0; I != *NumExpansions; ++I) {
4535  Sema::ArgumentPackSubstitutionIndexRAII SubstIndex(*this, I);
4536 
4537  // Instantiate the initializer.
4538  ExprResult TempInit = SubstInitializer(Init->getInit(), TemplateArgs,
4539  /*CXXDirectInit=*/true);
4540  if (TempInit.isInvalid()) {
4541  AnyErrors = true;
4542  break;
4543  }
4544 
4545  // Instantiate the base type.
4546  TypeSourceInfo *BaseTInfo = SubstType(Init->getTypeSourceInfo(),
4547  TemplateArgs,
4548  Init->getSourceLocation(),
4549  New->getDeclName());
4550  if (!BaseTInfo) {
4551  AnyErrors = true;
4552  break;
4553  }
4554 
4555  // Build the initializer.
4556  MemInitResult NewInit = BuildBaseInitializer(BaseTInfo->getType(),
4557  BaseTInfo, TempInit.get(),
4558  New->getParent(),
4559  SourceLocation());
4560  if (NewInit.isInvalid()) {
4561  AnyErrors = true;
4562  break;
4563  }
4564 
4565  NewInits.push_back(NewInit.get());
4566  }
4567 
4568  continue;
4569  }
4570 
4571  // Instantiate the initializer.
4572  ExprResult TempInit = SubstInitializer(Init->getInit(), TemplateArgs,
4573  /*CXXDirectInit=*/true);
4574  if (TempInit.isInvalid()) {
4575  AnyErrors = true;
4576  continue;
4577  }
4578 
4579  MemInitResult NewInit;
4580  if (Init->isDelegatingInitializer() || Init->isBaseInitializer()) {
4581  TypeSourceInfo *TInfo = SubstType(Init->getTypeSourceInfo(),
4582  TemplateArgs,
4583  Init->getSourceLocation(),
4584  New->getDeclName());
4585  if (!TInfo) {
4586  AnyErrors = true;
4587  New->setInvalidDecl();
4588  continue;
4589  }
4590 
4591  if (Init->isBaseInitializer())
4592  NewInit = BuildBaseInitializer(TInfo->getType(), TInfo, TempInit.get(),
4593  New->getParent(), EllipsisLoc);
4594  else
4595  NewInit = BuildDelegatingInitializer(TInfo, TempInit.get(),
4596  cast<CXXRecordDecl>(CurContext->getParent()));
4597  } else if (Init->isMemberInitializer()) {
4598  FieldDecl *Member = cast_or_null<FieldDecl>(FindInstantiatedDecl(
4599  Init->getMemberLocation(),
4600  Init->getMember(),
4601  TemplateArgs));
4602  if (!Member) {
4603  AnyErrors = true;
4604  New->setInvalidDecl();
4605  continue;
4606  }
4607 
4608  NewInit = BuildMemberInitializer(Member, TempInit.get(),
4609  Init->getSourceLocation());
4610  } else if (Init->isIndirectMemberInitializer()) {
4611  IndirectFieldDecl *IndirectMember =
4612  cast_or_null<IndirectFieldDecl>(FindInstantiatedDecl(
4613  Init->getMemberLocation(),
4614  Init->getIndirectMember(), TemplateArgs));
4615 
4616  if (!IndirectMember) {
4617  AnyErrors = true;
4618  New->setInvalidDecl();
4619  continue;
4620  }
4621 
4622  NewInit = BuildMemberInitializer(IndirectMember, TempInit.get(),
4623  Init->getSourceLocation());
4624  }
4625 
4626  if (NewInit.isInvalid()) {
4627  AnyErrors = true;
4628  New->setInvalidDecl();
4629  } else {
4630  NewInits.push_back(NewInit.get());
4631  }
4632  }
4633 
4634  // Assign all the initializers to the new constructor.
4635  ActOnMemInitializers(New,
4636  /*FIXME: ColonLoc */
4637  SourceLocation(),
4638  NewInits,
4639  AnyErrors);
4640 }
4641 
4642 // TODO: this could be templated if the various decl types used the
4643 // same method name.
4645  ClassTemplateDecl *Instance) {
4646  Pattern = Pattern->getCanonicalDecl();
4647 
4648  do {
4649  Instance = Instance->getCanonicalDecl();
4650  if (Pattern == Instance) return true;
4651  Instance = Instance->getInstantiatedFromMemberTemplate();
4652  } while (Instance);
4653 
4654  return false;
4655 }
4656 
4658  FunctionTemplateDecl *Instance) {
4659  Pattern = Pattern->getCanonicalDecl();
4660 
4661  do {
4662  Instance = Instance->getCanonicalDecl();
4663  if (Pattern == Instance) return true;
4664  Instance = Instance->getInstantiatedFromMemberTemplate();
4665  } while (Instance);
4666 
4667  return false;
4668 }
4669 
4670 static bool
4673  Pattern
4674  = cast<ClassTemplatePartialSpecializationDecl>(Pattern->getCanonicalDecl());
4675  do {
4676  Instance = cast<ClassTemplatePartialSpecializationDecl>(
4677  Instance->getCanonicalDecl());
4678  if (Pattern == Instance)
4679  return true;
4680  Instance = Instance->getInstantiatedFromMember();
4681  } while (Instance);
4682 
4683  return false;
4684 }
4685 
4686 static bool isInstantiationOf(CXXRecordDecl *Pattern,
4687  CXXRecordDecl *Instance) {
4688  Pattern = Pattern->getCanonicalDecl();
4689 
4690  do {
4691  Instance = Instance->getCanonicalDecl();
4692  if (Pattern == Instance) return true;
4693  Instance = Instance->getInstantiatedFromMemberClass();
4694  } while (Instance);
4695 
4696  return false;
4697 }
4698 
4699 static bool isInstantiationOf(FunctionDecl *Pattern,
4700  FunctionDecl *Instance) {
4701  Pattern = Pattern->getCanonicalDecl();
4702 
4703  do {
4704  Instance = Instance->getCanonicalDecl();
4705  if (Pattern == Instance) return true;
4706  Instance = Instance->getInstantiatedFromMemberFunction();
4707  } while (Instance);
4708 
4709  return false;
4710 }
4711 
4712 static bool isInstantiationOf(EnumDecl *Pattern,
4713  EnumDecl *Instance) {
4714  Pattern = Pattern->getCanonicalDecl();
4715 
4716  do {
4717  Instance = Instance->getCanonicalDecl();
4718  if (Pattern == Instance) return true;
4719  Instance = Instance->getInstantiatedFromMemberEnum();
4720  } while (Instance);
4721 
4722  return false;
4723 }
4724 
4725 static bool isInstantiationOf(UsingShadowDecl *Pattern,
4726  UsingShadowDecl *Instance,
4727  ASTContext &C) {
4729  Pattern);
4730 }
4731 
4732 static bool isInstantiationOf(UsingDecl *Pattern, UsingDecl *Instance,
4733  ASTContext &C) {
4734  return declaresSameEntity(C.getInstantiatedFromUsingDecl(Instance), Pattern);
4735 }
4736 
4737 template<typename T>
4738 static bool isInstantiationOfUnresolvedUsingDecl(T *Pattern, Decl *Other,
4739  ASTContext &Ctx) {
4740  // An unresolved using declaration can instantiate to an unresolved using
4741  // declaration, or to a using declaration or a using declaration pack.
4742  //
4743  // Multiple declarations can claim to be instantiated from an unresolved
4744  // using declaration if it's a pack expansion. We want the UsingPackDecl
4745  // in that case, not the individual UsingDecls within the pack.
4746  bool OtherIsPackExpansion;
4747  NamedDecl *OtherFrom;
4748  if (auto *OtherUUD = dyn_cast<T>(Other)) {
4749  OtherIsPackExpansion = OtherUUD->isPackExpansion();
4750  OtherFrom = Ctx.getInstantiatedFromUsingDecl(OtherUUD);
4751  } else if (auto *OtherUPD = dyn_cast<UsingPackDecl>(Other)) {
4752  OtherIsPackExpansion = true;
4753  OtherFrom = OtherUPD->getInstantiatedFromUsingDecl();
4754  } else if (auto *OtherUD = dyn_cast<UsingDecl>(Other)) {
4755  OtherIsPackExpansion = false;
4756  OtherFrom = Ctx.getInstantiatedFromUsingDecl(OtherUD);
4757  } else {
4758  return false;
4759  }
4760  return Pattern->isPackExpansion() == OtherIsPackExpansion &&
4761  declaresSameEntity(OtherFrom, Pattern);
4762 }
4763 
4765  VarDecl *Instance) {
4766  assert(Instance->isStaticDataMember());
4767 
4768  Pattern = Pattern->getCanonicalDecl();
4769 
4770  do {
4771  Instance = Instance->getCanonicalDecl();
4772  if (Pattern == Instance) return true;
4773  Instance = Instance->getInstantiatedFromStaticDataMember();
4774  } while (Instance);
4775 
4776  return false;
4777 }
4778 
4779 // Other is the prospective instantiation
4780 // D is the prospective pattern
4781 static bool isInstantiationOf(ASTContext &Ctx, NamedDecl *D, Decl *Other) {
4782  if (auto *UUD = dyn_cast<UnresolvedUsingTypenameDecl>(D))
4783  return isInstantiationOfUnresolvedUsingDecl(UUD, Other, Ctx);
4784 
4785  if (auto *UUD = dyn_cast<UnresolvedUsingValueDecl>(D))
4786  return isInstantiationOfUnresolvedUsingDecl(UUD, Other, Ctx);
4787 
4788  if (D->getKind() != Other->getKind())
4789  return false;
4790 
4791  if (auto *Record = dyn_cast<CXXRecordDecl>(Other))
4792  return isInstantiationOf(cast<CXXRecordDecl>(D), Record);
4793 
4794  if (auto *Function = dyn_cast<FunctionDecl>(Other))
4795  return isInstantiationOf(cast<FunctionDecl>(D), Function);
4796 
4797  if (auto *Enum = dyn_cast<EnumDecl>(Other))
4798  return isInstantiationOf(cast<EnumDecl>(D), Enum);
4799 
4800  if (auto *Var = dyn_cast<VarDecl>(Other))
4801  if (Var->isStaticDataMember())
4802  return isInstantiationOfStaticDataMember(cast<VarDecl>(D), Var);
4803 
4804  if (auto *Temp = dyn_cast<ClassTemplateDecl>(Other))
4805  return isInstantiationOf(cast<ClassTemplateDecl>(D), Temp);
4806 
4807  if (auto *Temp = dyn_cast<FunctionTemplateDecl>(Other))
4808  return isInstantiationOf(cast<FunctionTemplateDecl>(D), Temp);
4809 
4810  if (auto *PartialSpec =
4811  dyn_cast<ClassTemplatePartialSpecializationDecl>(Other))
4812  return isInstantiationOf(cast<ClassTemplatePartialSpecializationDecl>(D),
4813  PartialSpec);
4814 
4815  if (auto *Field = dyn_cast<FieldDecl>(Other)) {
4816  if (!Field->getDeclName()) {
4817  // This is an unnamed field.
4819  cast<FieldDecl>(D));
4820  }
4821  }
4822 
4823  if (auto *Using = dyn_cast<UsingDecl>(Other))
4824  return isInstantiationOf(cast<UsingDecl>(D), Using, Ctx);
4825 
4826  if (auto *Shadow = dyn_cast<UsingShadowDecl>(Other))
4827  return isInstantiationOf(cast<UsingShadowDecl>(D), Shadow, Ctx);
4828 
4829  return D->getDeclName() &&
4830  D->getDeclName() == cast<NamedDecl>(Other)->getDeclName();
4831 }
4832 
4833 template<typename ForwardIterator>
4835  NamedDecl *D,
4836  ForwardIterator first,
4837  ForwardIterator last) {
4838  for (; first != last; ++first)
4839  if (isInstantiationOf(Ctx, D, *first))
4840  return cast<NamedDecl>(*first);
4841 
4842  return nullptr;
4843 }
4844 
4845 /// Finds the instantiation of the given declaration context
4846 /// within the current instantiation.
4847 ///
4848 /// \returns NULL if there was an error
4850  const MultiLevelTemplateArgumentList &TemplateArgs) {
4851  if (NamedDecl *D = dyn_cast<NamedDecl>(DC)) {
4852  Decl* ID = FindInstantiatedDecl(Loc, D, TemplateArgs, true);
4853  return cast_or_null<DeclContext>(ID);
4854  } else return DC;
4855 }
4856 
4857 /// Find the instantiation of the given declaration within the
4858 /// current instantiation.
4859 ///
4860 /// This routine is intended to be used when \p D is a declaration
4861 /// referenced from within a template, that needs to mapped into the
4862 /// corresponding declaration within an instantiation. For example,
4863 /// given:
4864 ///
4865 /// \code
4866 /// template<typename T>
4867 /// struct X {
4868 /// enum Kind {
4869 /// KnownValue = sizeof(T)
4870 /// };
4871 ///
4872 /// bool getKind() const { return KnownValue; }
4873 /// };
4874 ///
4875 /// template struct X<int>;
4876 /// \endcode
4877 ///
4878 /// In the instantiation of <tt>X<int>::getKind()</tt>, we need to map the
4879 /// \p EnumConstantDecl for \p KnownValue (which refers to
4880 /// <tt>X<T>::<Kind>::KnownValue</tt>) to its instantiation
4881 /// (<tt>X<int>::<Kind>::KnownValue</tt>). \p FindInstantiatedDecl performs
4882 /// this mapping from within the instantiation of <tt>X<int></tt>.
4884  const MultiLevelTemplateArgumentList &TemplateArgs,
4885  bool FindingInstantiatedContext) {
4886  DeclContext *ParentDC = D->getDeclContext();
4887  // FIXME: Parmeters of pointer to functions (y below) that are themselves
4888  // parameters (p below) can have their ParentDC set to the translation-unit
4889  // - thus we can not consistently check if the ParentDC of such a parameter
4890  // is Dependent or/and a FunctionOrMethod.
4891  // For e.g. this code, during Template argument deduction tries to
4892  // find an instantiated decl for (T y) when the ParentDC for y is
4893  // the translation unit.
4894  // e.g. template <class T> void Foo(auto (*p)(T y) -> decltype(y())) {}
4895  // float baz(float(*)()) { return 0.0; }
4896  // Foo(baz);
4897  // The better fix here is perhaps to ensure that a ParmVarDecl, by the time
4898  // it gets here, always has a FunctionOrMethod as its ParentDC??
4899  // For now:
4900  // - as long as we have a ParmVarDecl whose parent is non-dependent and
4901  // whose type is not instantiation dependent, do nothing to the decl
4902  // - otherwise find its instantiated decl.
4903  if (isa<ParmVarDecl>(D) && !ParentDC->isDependentContext() &&
4904  !cast<ParmVarDecl>(D)->getType()->isInstantiationDependentType())
4905  return D;
4906  if (isa<ParmVarDecl>(D) || isa<NonTypeTemplateParmDecl>(D) ||
4907  isa<TemplateTypeParmDecl>(D) || isa<TemplateTemplateParmDecl>(D) ||
4908  (ParentDC->isFunctionOrMethod() && ParentDC->isDependentContext()) ||
4909  (isa<CXXRecordDecl>(D) && cast<CXXRecordDecl>(D)->isLambda())) {
4910  // D is a local of some kind. Look into the map of local
4911  // declarations to their instantiations.
4912  if (CurrentInstantiationScope) {
4913  if (auto Found = CurrentInstantiationScope->findInstantiationOf(D)) {
4914  if (Decl *FD = Found->dyn_cast<Decl *>())
4915  return cast<NamedDecl>(FD);
4916 
4917  int PackIdx = ArgumentPackSubstitutionIndex;
4918  assert(PackIdx != -1 &&
4919  "found declaration pack but not pack expanding");
4920  typedef LocalInstantiationScope::DeclArgumentPack DeclArgumentPack;
4921  return cast<NamedDecl>((*Found->get<DeclArgumentPack *>())[PackIdx]);
4922  }
4923  }
4924 
4925  // If we're performing a partial substitution during template argument
4926  // deduction, we may not have values for template parameters yet. They
4927  // just map to themselves.
4928  if (isa<NonTypeTemplateParmDecl>(D) || isa<TemplateTypeParmDecl>(D) ||
4929  isa<TemplateTemplateParmDecl>(D))
4930  return D;
4931 
4932  if (D->isInvalidDecl())
4933  return nullptr;
4934 
4935  // Normally this function only searches for already instantiated declaration
4936  // however we have to make an exclusion for local types used before
4937  // definition as in the code:
4938  //
4939  // template<typename T> void f1() {
4940  // void g1(struct x1);
4941  // struct x1 {};
4942  // }
4943  //
4944  // In this case instantiation of the type of 'g1' requires definition of
4945  // 'x1', which is defined later. Error recovery may produce an enum used
4946  // before definition. In these cases we need to instantiate relevant
4947  // declarations here.
4948  bool NeedInstantiate = false;
4949  if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(D))
4950  NeedInstantiate = RD->isLocalClass();
4951  else
4952  NeedInstantiate = isa<EnumDecl>(D);
4953  if (NeedInstantiate) {
4954  Decl *Inst = SubstDecl(D, CurContext, TemplateArgs);
4955  CurrentInstantiationScope->InstantiatedLocal(D, Inst);
4956  return cast<TypeDecl>(Inst);
4957  }
4958 
4959  // If we didn't find the decl, then we must have a label decl that hasn't
4960  // been found yet. Lazily instantiate it and return it now.
4961  assert(isa<LabelDecl>(D));
4962 
4963  Decl *Inst = SubstDecl(D, CurContext, TemplateArgs);
4964  assert(Inst && "Failed to instantiate label??");
4965 
4966  CurrentInstantiationScope->InstantiatedLocal(D, Inst);
4967  return cast<LabelDecl>(Inst);
4968  }
4969 
4970  // For variable template specializations, update those that are still
4971  // type-dependent.
4972  if (VarTemplateSpecializationDecl *VarSpec =
4973  dyn_cast<VarTemplateSpecializationDecl>(D)) {
4974  bool InstantiationDependent = false;
4975  const TemplateArgumentListInfo &VarTemplateArgs =
4976  VarSpec->getTemplateArgsInfo();
4978  VarTemplateArgs, InstantiationDependent))
4979  D = cast<NamedDecl>(
4980  SubstDecl(D, VarSpec->getDeclContext(), TemplateArgs));
4981  return D;
4982  }
4983 
4984  if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(D)) {
4985  if (!Record->isDependentContext())
4986  return D;
4987 
4988  // Determine whether this record is the "templated" declaration describing
4989  // a class template or class template partial specialization.
4990  ClassTemplateDecl *ClassTemplate = Record->getDescribedClassTemplate();
4991  if (ClassTemplate)
4992  ClassTemplate = ClassTemplate->getCanonicalDecl();
4993  else if (ClassTemplatePartialSpecializationDecl *PartialSpec
4994  = dyn_cast<ClassTemplatePartialSpecializationDecl>(Record))
4995  ClassTemplate = PartialSpec->getSpecializedTemplate()->getCanonicalDecl();
4996 
4997  // Walk the current context to find either the record or an instantiation of
4998  // it.
4999  DeclContext *DC = CurContext;
5000  while (!DC->isFileContext()) {
5001  // If we're performing substitution while we're inside the template
5002  // definition, we'll find our own context. We're done.
5003  if (DC->Equals(Record))
5004  return Record;
5005 
5006  if (CXXRecordDecl *InstRecord = dyn_cast<CXXRecordDecl>(DC)) {
5007  // Check whether we're in the process of instantiating a class template
5008  // specialization of the template we're mapping.
5009  if (ClassTemplateSpecializationDecl *InstSpec
5010  = dyn_cast<ClassTemplateSpecializationDecl>(InstRecord)){
5011  ClassTemplateDecl *SpecTemplate = InstSpec->getSpecializedTemplate();
5012  if (ClassTemplate && isInstantiationOf(ClassTemplate, SpecTemplate))
5013  return InstRecord;
5014  }
5015 
5016  // Check whether we're in the process of instantiating a member class.
5017  if (isInstantiationOf(Record, InstRecord))
5018  return InstRecord;
5019  }
5020 
5021  // Move to the outer template scope.
5022  if (FunctionDecl *FD = dyn_cast<FunctionDecl>(DC)) {
5023  if (FD->getFriendObjectKind() && FD->getDeclContext()->isFileContext()){
5024  DC = FD->getLexicalDeclContext();
5025  continue;
5026  }
5027  // An implicit deduction guide acts as if it's within the class template
5028  // specialization described by its name and first N template params.
5029  auto *Guide = dyn_cast<CXXDeductionGuideDecl>(FD);
5030  if (Guide && Guide->isImplicit()) {
5031  TemplateDecl *TD = Guide->getDeducedTemplate();
5032  // Convert the arguments to an "as-written" list.
5033  TemplateArgumentListInfo Args(Loc, Loc);
5034  for (TemplateArgument Arg : TemplateArgs.getInnermost().take_front(
5035  TD->getTemplateParameters()->size())) {
5036  ArrayRef<TemplateArgument> Unpacked(Arg);
5037  if (Arg.getKind() == TemplateArgument::Pack)
5038  Unpacked = Arg.pack_elements();
5039  for (TemplateArgument UnpackedArg : Unpacked)
5040  Args.addArgument(
5041  getTrivialTemplateArgumentLoc(UnpackedArg, QualType(), Loc));
5042  }
5043  QualType T = CheckTemplateIdType(TemplateName(TD), Loc, Args);
5044  if (T.isNull())
5045  return nullptr;
5046  auto *SubstRecord = T->getAsCXXRecordDecl();
5047  assert(SubstRecord && "class template id not a class type?");
5048  // Check that this template-id names the primary template and not a
5049  // partial or explicit specialization. (In the latter cases, it's
5050  // meaningless to attempt to find an instantiation of D within the
5051  // specialization.)
5052  // FIXME: The standard doesn't say what should happen here.
5053  if (FindingInstantiatedContext &&
5054  usesPartialOrExplicitSpecialization(
5055  Loc, cast<ClassTemplateSpecializationDecl>(SubstRecord))) {
5056  Diag(Loc, diag::err_specialization_not_primary_template)
5057  << T << (SubstRecord->getTemplateSpecializationKind() ==
5059  return nullptr;
5060  }
5061  DC = SubstRecord;
5062  continue;
5063  }
5064  }
5065 
5066  DC = DC->getParent();
5067  }
5068 
5069  // Fall through to deal with other dependent record types (e.g.,
5070  // anonymous unions in class templates).
5071  }
5072 
5073  if (!ParentDC->isDependentContext())
5074  return D;
5075 
5076  ParentDC = FindInstantiatedContext(Loc, ParentDC, TemplateArgs);
5077  if (!ParentDC)
5078  return nullptr;
5079 
5080  if (ParentDC != D->getDeclContext()) {
5081  // We performed some kind of instantiation in the parent context,
5082  // so now we need to look into the instantiated parent context to
5083  // find the instantiation of the declaration D.
5084 
5085  // If our context used to be dependent, we may need to instantiate
5086  // it before performing lookup into that context.
5087  bool IsBeingInstantiated = false;
5088  if (CXXRecordDecl *Spec = dyn_cast<CXXRecordDecl>(ParentDC)) {
5089  if (!Spec->isDependentContext()) {
5090  QualType T = Context.getTypeDeclType(Spec);
5091  const RecordType *Tag = T->getAs<RecordType>();
5092  assert(Tag && "type of non-dependent record is not a RecordType");
5093  if (Tag->isBeingDefined())
5094  IsBeingInstantiated = true;
5095  if (!Tag->isBeingDefined() &&
5096  RequireCompleteType(Loc, T, diag::err_incomplete_type))
5097  return nullptr;
5098 
5099  ParentDC = Tag->getDecl();
5100  }
5101  }
5102 
5103  NamedDecl *Result = nullptr;
5104  // FIXME: If the name is a dependent name, this lookup won't necessarily
5105  // find it. Does that ever matter?
5106  if (auto Name = D->getDeclName()) {
5107  DeclarationNameInfo NameInfo(Name, D->getLocation());
5108  Name = SubstDeclarationNameInfo(NameInfo, TemplateArgs).getName();
5109  if (!Name)
5110  return nullptr;
5111  DeclContext::lookup_result Found = ParentDC->lookup(Name);
5112  Result = findInstantiationOf(Context, D, Found.begin(), Found.end());
5113  } else {
5114  // Since we don't have a name for the entity we're looking for,
5115  // our only option is to walk through all of the declarations to
5116  // find that name. This will occur in a few cases:
5117  //
5118  // - anonymous struct/union within a template
5119  // - unnamed class/struct/union/enum within a template
5120  //
5121  // FIXME: Find a better way to find these instantiations!
5122  Result = findInstantiationOf(Context, D,
5123  ParentDC->decls_begin(),
5124  ParentDC->decls_end());
5125  }
5126 
5127  if (!Result) {
5128  if (isa<UsingShadowDecl>(D)) {
5129  // UsingShadowDecls can instantiate to nothing because of using hiding.
5130  } else if (Diags.hasErrorOccurred()) {
5131  // We've already complained about something, so most likely this
5132  // declaration failed to instantiate. There's no point in complaining
5133  // further, since this is normal in invalid code.
5134  } else if (IsBeingInstantiated) {
5135  // The class in which this member exists is currently being
5136  // instantiated, and we haven't gotten around to instantiating this
5137  // member yet. This can happen when the code uses forward declarations
5138  // of member classes, and introduces ordering dependencies via
5139  // template instantiation.
5140  Diag(Loc, diag::err_member_not_yet_instantiated)
5141  << D->getDeclName()
5142  << Context.getTypeDeclType(cast<CXXRecordDecl>(ParentDC));
5143  Diag(D->getLocation(), diag::note_non_instantiated_member_here);
5144  } else if (EnumConstantDecl *ED = dyn_cast<EnumConstantDecl>(D)) {
5145  // This enumeration constant was found when the template was defined,
5146  // but can't be found in the instantiation. This can happen if an
5147  // unscoped enumeration member is explicitly specialized.
5148  EnumDecl *Enum = cast<EnumDecl>(ED->getLexicalDeclContext());
5149  EnumDecl *Spec = cast<EnumDecl>(FindInstantiatedDecl(Loc, Enum,
5150  TemplateArgs));
5151  assert(Spec->getTemplateSpecializationKind() ==
5153  Diag(Loc, diag::err_enumerator_does_not_exist)
5154  << D->getDeclName()
5155  << Context.getTypeDeclType(cast<TypeDecl>(Spec->getDeclContext()));
5156  Diag(Spec->getLocation(), diag::note_enum_specialized_here)
5157  << Context.getTypeDeclType(Spec);
5158  } else {
5159  // We should have found something, but didn't.
5160  llvm_unreachable("Unable to find instantiation of declaration!");
5161  }
5162  }
5163 
5164  D = Result;
5165  }
5166 
5167  return D;
5168 }
5169 
5170 /// Performs template instantiation for all implicit template
5171 /// instantiations we have seen until this point.
5173  while (!PendingLocalImplicitInstantiations.empty() ||
5174  (!LocalOnly && !PendingInstantiations.empty())) {
5176 
5177  if (PendingLocalImplicitInstantiations.empty()) {
5178  Inst = PendingInstantiations.front();
5179  PendingInstantiations.pop_front();
5180  } else {
5181  Inst = PendingLocalImplicitInstantiations.front();
5182  PendingLocalImplicitInstantiations.pop_front();
5183  }
5184 
5185  // Instantiate function definitions
5186  if (FunctionDecl *Function = dyn_cast<FunctionDecl>(Inst.first)) {
5187  bool DefinitionRequired = Function->getTemplateSpecializationKind() ==
5189  InstantiateFunctionDefinition(/*FIXME:*/Inst.second, Function, true,
5190  DefinitionRequired, true);
5191  if (Function->isDefined())
5192  Function->setInstantiationIsPending(false);
5193  continue;
5194  }
5195 
5196  // Instantiate variable definitions
5197  VarDecl *Var = cast<VarDecl>(Inst.first);
5198 
5199  assert((Var->isStaticDataMember() ||
5200  isa<VarTemplateSpecializationDecl>(Var)) &&
5201  "Not a static data member, nor a variable template"
5202  " specialization?");
5203 
5204  // Don't try to instantiate declarations if the most recent redeclaration
5205  // is invalid.
5206  if (Var->getMostRecentDecl()->isInvalidDecl())
5207  continue;
5208 
5209  // Check if the most recent declaration has changed the specialization kind
5210  // and removed the need for implicit instantiation.
5212  case TSK_Undeclared:
5213  llvm_unreachable("Cannot instantitiate an undeclared specialization.");
5216  continue; // No longer need to instantiate this type.
5218  // We only need an instantiation if the pending instantiation *is* the
5219  // explicit instantiation.
5220  if (Var != Var->getMostRecentDecl())
5221  continue;
5222  break;
5224  break;
5225  }
5226 
5227  PrettyDeclStackTraceEntry CrashInfo(Context, Var, SourceLocation(),
5228  "instantiating variable definition");
5229  bool DefinitionRequired = Var->getTemplateSpecializationKind() ==
5231 
5232  // Instantiate static data member definitions or variable template
5233  // specializations.
5234  InstantiateVariableDefinition(/*FIXME:*/ Inst.second, Var, true,
5235  DefinitionRequired, true);
5236  }
5237 }
5238 
5240  const MultiLevelTemplateArgumentList &TemplateArgs) {
5241  for (auto DD : Pattern->ddiags()) {
5242  switch (DD->getKind()) {
5244  HandleDependentAccessCheck(*DD, TemplateArgs);
5245  break;
5246  }
5247  }
5248 }
bool isPackExpansion() const
Whether this parameter pack is a pack expansion.
VarTemplateDecl * getDescribedVarTemplate() const
Retrieves the variable template that is described by this variable declaration.
Definition: Decl.cpp:2426
The lookup results will be used for redeclaration of a name with external linkage; non-visible lookup...
Definition: Sema.h:3048
Defines the clang::ASTContext interface.
FunctionDecl * getDefinition()
Get the definition for this declaration.
Definition: Decl.h:1989
void InstantiateClassMembers(SourceLocation PointOfInstantiation, CXXRecordDecl *Instantiation, const MultiLevelTemplateArgumentList &TemplateArgs, TemplateSpecializationKind TSK)
Instantiates the definitions of all of the member of the given class, which is an instantiation of a ...
static void collectUnexpandedParameterPacks(Sema &S, TemplateParameterList *Params, SmallVectorImpl< UnexpandedParameterPack > &Unexpanded)
The lookup results will be used for redeclaration of a name, if an entity by that name already exists...
Definition: Sema.h:3044
void setImplicit(bool I=true)
Definition: DeclBase.h:553
Represents a function declaration or definition.
Definition: Decl.h:1714
NamespaceDecl * getStdNamespace() const
static DiagnosticBuilder Diag(DiagnosticsEngine *Diags, const LangOptions &Features, FullSourceLoc TokLoc, const char *TokBegin, const char *TokRangeBegin, const char *TokRangeEnd, unsigned DiagID)
Produce a diagnostic highlighting some portion of a literal.
ExprResult PerformContextuallyConvertToBool(Expr *From)
PerformContextuallyConvertToBool - Perform a contextual conversion of the expression From to bool (C+...
no exception specification
virtual void HandleCXXStaticMemberVarInstantiation(VarDecl *D)
HandleCXXStaticMemberVarInstantiation - Tell the consumer that this.
Definition: ASTConsumer.h:112
bool TemplateParameterListsAreEqual(TemplateParameterList *New, TemplateParameterList *Old, bool Complain, TemplateParameterListEqualKind Kind, SourceLocation TemplateArgLoc=SourceLocation())
Determine whether the given template parameter lists are equivalent.
void InstantiateAttrsForDecl(const MultiLevelTemplateArgumentList &TemplateArgs, const Decl *Pattern, Decl *Inst, LateInstantiatedAttrVec *LateAttrs=nullptr, LocalInstantiationScope *OuterMostScope=nullptr)
A (possibly-)qualified type.
Definition: Type.h:654
void ActOnOpenMPDeclareReductionCombinerStart(Scope *S, Decl *D)
Initialize declare reduction construct initializer.
const char * getDeclKindName() const
Definition: DeclBase.cpp:123
void InstantiatedLocal(const Decl *D, Decl *Inst)
bool CheckTemplateParameterList(TemplateParameterList *NewParams, TemplateParameterList *OldParams, TemplateParamListContext TPC)
Checks the validity of a template parameter list, possibly considering the template parameter list fr...
void setTemplateKeywordLoc(SourceLocation Loc)
Sets the location of the template keyword.
Decl * VisitVarDecl(VarDecl *D, bool InstantiatingVarTemplate, ArrayRef< BindingDecl *> *Bindings=nullptr)
bool isOverloadedOperator() const
Whether this function declaration represents an C++ overloaded operator, e.g., "operator+".
Definition: Decl.h:2322
ASTConsumer - This is an abstract interface that should be implemented by clients that read ASTs...
Definition: ASTConsumer.h:34
A stack-allocated class that identifies which local variable declaration instantiations are present i...
Definition: Template.h:228
const TypeClass * getTypePtr() const
Definition: TypeLoc.h:404
void InstantiateExceptionSpec(SourceLocation PointOfInstantiation, FunctionDecl *Function)
std::vector< std::unique_ptr< TemplateInstantiationCallback > > TemplateInstCallbacks
The template instantiation callbacks to trace or track instantiations (objects can be chained)...
Definition: Sema.h:7293
SourceRange getSourceRange() const LLVM_READONLY
Retrieve the source range covering the entirety of this nested-name-specifier.
static TypeAliasTemplateDecl * Create(ASTContext &C, DeclContext *DC, SourceLocation L, DeclarationName Name, TemplateParameterList *Params, NamedDecl *Decl)
Create a function template node.
FunctionDecl * findSpecialization(ArrayRef< TemplateArgument > Args, void *&InsertPos)
Return the specialization with the provided arguments if it exists, otherwise return the insertion po...
Ordinary name lookup, which finds ordinary names (functions, variables, typedefs, etc...
Definition: Sema.h:2993
SourceRange getBraceRange() const
Definition: Decl.h:3133
bool willHaveBody() const
True if this function will eventually have a body, once it&#39;s fully parsed.
Definition: Decl.h:2200
DeclarationName getCXXConstructorName(CanQualType Ty)
getCXXConstructorName - Returns the name of a C++ constructor for the given Type. ...
static void instantiateDependentAllocAlignAttr(Sema &S, const MultiLevelTemplateArgumentList &TemplateArgs, const AllocAlignAttr *Align, Decl *New)
InClassInitStyle getInClassInitStyle() const
Get the kind of (C++11) default member initializer that this field has.
Definition: Decl.h:2649
NestedNameSpecifierLoc getTemplateQualifierLoc() const
Definition: TemplateBase.h:526
void addOuterTemplateArguments(const TemplateArgumentList *TemplateArgs)
Add a new outermost level to the multi-level template argument list.
Definition: Template.h:134
Expr * getUnderlyingExpr() const
Definition: Type.h:3937
static IndirectFieldDecl * Create(ASTContext &C, DeclContext *DC, SourceLocation L, IdentifierInfo *Id, QualType T, llvm::MutableArrayRef< NamedDecl *> CH)
Definition: Decl.cpp:4373
Stmt - This represents one statement.
Definition: Stmt.h:66
Expr * getBitWidth() const
Definition: Decl.h:2610
We are matching the template parameter lists of two templates that might be redeclarations.
Definition: Sema.h:6442
void setPreviousDecl(decl_type *PrevDecl)
Set the previous declaration.
Definition: Decl.h:4260
Provides information about an attempted template argument deduction, whose success or failure was des...
ClassTemplateSpecializationDecl * findSpecialization(ArrayRef< TemplateArgument > Args, void *&InsertPos)
Return the specialization with the provided arguments if it exists, otherwise return the insertion po...
static bool isDeclWithinFunction(const Decl *D)
VarDecl * getTemplatedDecl() const
Get the underlying variable declarations of the template.
bool isOutOfLine() const override
Determine whether this is or was instantiated from an out-of-line definition of a member function...
Definition: Decl.cpp:3539
An instance of this object exists for each enum constant that is defined.
Definition: Decl.h:2728
StorageClass getStorageClass() const
Returns the storage class as written in the source.
Definition: Decl.h:1017
void setTypedefNameForAnonDecl(TypedefNameDecl *TDD)
Definition: Decl.cpp:3780
Represents the declaration of a typedef-name via the &#39;typedef&#39; type specifier.
Definition: Decl.h:2960
bool CheckTemplatePartialSpecializationArgs(SourceLocation Loc, TemplateDecl *PrimaryTemplate, unsigned NumExplicitArgs, ArrayRef< TemplateArgument > Args)
Check the non-type template arguments of a class template partial specialization according to C++ [te...
bool isConstexpr() const
Whether this is a (C++11) constexpr function or constexpr constructor.
Definition: Decl.h:2088
VarTemplateSpecializationDecl * BuildVarTemplateInstantiation(VarTemplateDecl *VarTemplate, VarDecl *FromVar, const TemplateArgumentList &TemplateArgList, const TemplateArgumentListInfo &TemplateArgsInfo, SmallVectorImpl< TemplateArgument > &Converted, SourceLocation PointOfInstantiation, void *InsertPos, LateInstantiatedAttrVec *LateAttrs=nullptr, LocalInstantiationScope *StartingScope=nullptr)
unsigned getNumExpansionTypes() const
Retrieves the number of expansion types in an expanded parameter pack.
static TemplateTemplateParmDecl * Create(const ASTContext &C, DeclContext *DC, SourceLocation L, unsigned D, unsigned P, bool ParameterPack, IdentifierInfo *Id, TemplateParameterList *Params)
bool isSingleTagDecl() const
Asks if the result is a single tag decl.
Definition: Lookup.h:519
const Type * getTypeForDecl() const
Definition: Decl.h:2840
SemaDiagnosticBuilder Diag(SourceLocation Loc, unsigned DiagID)
Emit a diagnostic.
Definition: Sema.h:1270
Decl - This represents one declaration (or definition), e.g.
Definition: DeclBase.h:86
void setRangeEnd(SourceLocation E)
Definition: Decl.h:1942
static Expr * instantiateDependentFunctionAttrCondition(Sema &S, const MultiLevelTemplateArgumentList &TemplateArgs, const Attr *A, Expr *OldCond, const Decl *Tmpl, FunctionDecl *New)
IdentifierInfo * getGetterId() const
Definition: DeclCXX.h:3911
VarDecl * getDefinition(ASTContext &)
Get the real (not just tentative) definition for this declaration.
Definition: Decl.cpp:2112
ThreadStorageClassSpecifier getTSCSpec() const
Definition: Decl.h:1026
llvm::PointerUnion< Decl *, DeclArgumentPack * > * findInstantiationOf(const Decl *D)
Find the instantiation of the declaration D within the current instantiation scope.
Defines the C++ template declaration subclasses.
StringRef P
bool hasWrittenPrototype() const
Definition: Decl.h:2080
Decl * InstantiateTypedefNameDecl(TypedefNameDecl *D, bool IsTypeAlias)
SmallVector< CodeSynthesisContext, 16 > CodeSynthesisContexts
List of active code synthesis contexts.
Definition: Sema.h:7236
Not a friend object.
Definition: DeclBase.h:1099
Decl * getPreviousDecl()
Retrieve the previous declaration that declares the same entity as this declaration, or NULL if there is no previous declaration.
Definition: DeclBase.h:958
QualType getNonReferenceType() const
If Type is a reference type (e.g., const int&), returns the type that the reference refers to ("const...
Definition: Type.h:5977
FunctionDecl * InstantiateFunctionDeclaration(FunctionTemplateDecl *FTD, const TemplateArgumentList *Args, SourceLocation Loc)
Instantiate (or find existing instantiation of) a function template with a given set of template argu...
SourceLocation getColonLoc() const
The location of the colon following the access specifier.
Definition: DeclCXX.h:154
bool isCXXForRangeDecl() const
Determine whether this variable is the for-range-declaration in a C++0x for-range statement...
Definition: Decl.h:1332
bool isExpandedParameterPack() const
Whether this parameter is a template template parameter pack that has a known list of different templ...
std::deque< PendingImplicitInstantiation > PendingLocalImplicitInstantiations
The queue of implicit template instantiations that are required and must be performed within the curr...
Definition: Sema.h:7650
Declaration of a variable template.
Represent a C++ namespace.
Definition: Decl.h:514
const TargetInfo & getTargetInfo() const
Definition: ASTContext.h:672
bool getNoReturnAttr() const
Determine whether this function type includes the GNU noreturn attribute.
Definition: Type.h:3289
A container of type source information.
Definition: Decl.h:86
TemplateParameterList * getTemplateParameters() const
Get the list of template parameters.
std::pair< ValueDecl *, SourceLocation > PendingImplicitInstantiation
An entity for which implicit template instantiation is required.
Definition: Sema.h:7595
FieldDecl * getInstantiatedFromUnnamedFieldDecl(FieldDecl *Field)
TypeSourceInfo * getDefaultArgumentInfo() const
Retrieves the default argument&#39;s source information, if any.
bool isDefined(const FunctionDecl *&Definition) const
Returns true if the function has a definition that does not need to be instantiated.
Definition: Decl.cpp:2651
void setTemplateArgsInfo(const TemplateArgumentListInfo &ArgsInfo)
SourceLocation getLocEnd() const LLVM_READONLY
Definition: DeclBase.h:413
void setInitStyle(InitializationStyle Style)
Definition: Decl.h:1262
VarTemplatePartialSpecializationDecl * InstantiateVarTemplatePartialSpecialization(VarTemplateDecl *VarTemplate, VarTemplatePartialSpecializationDecl *PartialSpec)
Instantiate the declaration of a variable template partial specialization.
bool CheckTemplateArgumentList(TemplateDecl *Template, SourceLocation TemplateLoc, TemplateArgumentListInfo &TemplateArgs, bool PartialTemplateArgs, SmallVectorImpl< TemplateArgument > &Converted, bool UpdateArgsWithConversions=true)
Check that the given template arguments can be be provided to the given template, converting the argu...
Represents a C++ constructor within a class.
Definition: DeclCXX.h:2448
TemplateName SubstTemplateName(NestedNameSpecifierLoc QualifierLoc, TemplateName Name, SourceLocation Loc, const MultiLevelTemplateArgumentList &TemplateArgs)
bool CheckCXXDefaultArgExpr(SourceLocation CallLoc, FunctionDecl *FD, ParmVarDecl *Param)
Instantiate or parse a C++ default argument expression as necessary.
Definition: SemaExpr.cpp:4488
bool isVirtualAsWritten() const
Whether this function is marked as virtual explicitly.
Definition: Decl.h:2034
void InstantiateVariableDefinition(SourceLocation PointOfInstantiation, VarDecl *Var, bool Recursive=false, bool DefinitionRequired=false, bool AtEndOfTU=false)
Instantiate the definition of the given variable from its template.
static void instantiateDependentEnableIfAttr(Sema &S, const MultiLevelTemplateArgumentList &TemplateArgs, const EnableIfAttr *EIA, const Decl *Tmpl, FunctionDecl *New)
SourceLocation getTargetNameLoc() const
Returns the location of the identifier in the named namespace.
Definition: DeclCXX.h:3090
bool isCompleteDefinition() const
Return true if this decl has its body fully specified.
Definition: Decl.h:3157
bool defaultArgumentWasInherited() const
Determines whether the default argument was inherited from a previous declaration of this template...
TemplateParameterList * getTemplateParameters() const
Get the list of template parameters.
Represents a #pragma comment line.
Definition: Decl.h:139
bool isDefaultConstructor() const
Whether this constructor is a default constructor (C++ [class.ctor]p5), which can be used to default-...
Definition: DeclCXX.cpp:2289
NamedDecl * BuildUsingPackDecl(NamedDecl *InstantiatedFrom, ArrayRef< NamedDecl *> Expansions)
bool isPackExpansion() const
Whether this parameter pack is a pack expansion.
void Adopt(NestedNameSpecifierLoc Other)
Adopt an existing nested-name-specifier (with source-range information).
Definition: DeclSpec.cpp:125
void setRAngleLoc(SourceLocation Loc)
Definition: TemplateBase.h:566