SemaTemplateInstantiate.cpp revision c86a6e988184867b09aa17a619402d0e81d0fda0 
1//===------- SemaTemplateInstantiate.cpp - C++ Template 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.
10//
11//===----------------------------------------------------------------------===/
12
13#include "Sema.h"
14#include "TreeTransform.h"
15#include "clang/AST/ASTConsumer.h"
16#include "clang/AST/ASTContext.h"
17#include "clang/AST/Expr.h"
18#include "clang/AST/DeclTemplate.h"
19#include "clang/Parse/DeclSpec.h"
20#include "clang/Basic/LangOptions.h"
21#include "llvm/Support/Compiler.h"
22
23using namespace clang;
24
25//===----------------------------------------------------------------------===/
26// Template Instantiation Support
27//===----------------------------------------------------------------------===/
28
29/// \brief Retrieve the template argument list(s) that should be used to
30/// instantiate the definition of the given declaration.
31MultiLevelTemplateArgumentList
32Sema::getTemplateInstantiationArgs(NamedDecl *D) {
33  // Accumulate the set of template argument lists in this structure.
34  MultiLevelTemplateArgumentList Result;
35
36  DeclContext *Ctx = dyn_cast<DeclContext>(D);
37  if (!Ctx)
38    Ctx = D->getDeclContext();
39
40  while (!Ctx->isFileContext()) {
41    // Add template arguments from a class template instantiation.
42    if (ClassTemplateSpecializationDecl *Spec
43          = dyn_cast<ClassTemplateSpecializationDecl>(Ctx)) {
44      // We're done when we hit an explicit specialization.
45      if (Spec->getSpecializationKind() == TSK_ExplicitSpecialization)
46        break;
47
48      Result.addOuterTemplateArguments(&Spec->getTemplateInstantiationArgs());
49
50      // If this class template specialization was instantiated from a
51      // specialized member that is a class template, we're done.
52      assert(Spec->getSpecializedTemplate() && "No class template?");
53      if (Spec->getSpecializedTemplate()->isMemberSpecialization())
54        break;
55    }
56    // Add template arguments from a function template specialization.
57    else if (FunctionDecl *Function = dyn_cast<FunctionDecl>(Ctx)) {
58      if (Function->getTemplateSpecializationKind()
59            == TSK_ExplicitSpecialization)
60        break;
61
62      if (const TemplateArgumentList *TemplateArgs
63            = Function->getTemplateSpecializationArgs()) {
64        // Add the template arguments for this specialization.
65        Result.addOuterTemplateArguments(TemplateArgs);
66
67        // If this function was instantiated from a specialized member that is
68        // a function template, we're done.
69        assert(Function->getPrimaryTemplate() && "No function template?");
70        if (Function->getPrimaryTemplate()->isMemberSpecialization())
71          break;
72      }
73
74      // If this is a friend declaration and it declares an entity at
75      // namespace scope, take arguments from its lexical parent
76      // instead of its semantic parent.
77      if (Function->getFriendObjectKind() &&
78          Function->getDeclContext()->isFileContext()) {
79        Ctx = Function->getLexicalDeclContext();
80        continue;
81      }
82    }
83
84    Ctx = Ctx->getParent();
85  }
86
87  return Result;
88}
89
90Sema::InstantiatingTemplate::
91InstantiatingTemplate(Sema &SemaRef, SourceLocation PointOfInstantiation,
92                      Decl *Entity,
93                      SourceRange InstantiationRange)
94  :  SemaRef(SemaRef) {
95
96  Invalid = CheckInstantiationDepth(PointOfInstantiation,
97                                    InstantiationRange);
98  if (!Invalid) {
99    ActiveTemplateInstantiation Inst;
100    Inst.Kind = ActiveTemplateInstantiation::TemplateInstantiation;
101    Inst.PointOfInstantiation = PointOfInstantiation;
102    Inst.Entity = reinterpret_cast<uintptr_t>(Entity);
103    Inst.TemplateArgs = 0;
104    Inst.NumTemplateArgs = 0;
105    Inst.InstantiationRange = InstantiationRange;
106    SemaRef.ActiveTemplateInstantiations.push_back(Inst);
107    Invalid = false;
108  }
109}
110
111Sema::InstantiatingTemplate::InstantiatingTemplate(Sema &SemaRef,
112                                         SourceLocation PointOfInstantiation,
113                                         TemplateDecl *Template,
114                                         const TemplateArgument *TemplateArgs,
115                                         unsigned NumTemplateArgs,
116                                         SourceRange InstantiationRange)
117  : SemaRef(SemaRef) {
118
119  Invalid = CheckInstantiationDepth(PointOfInstantiation,
120                                    InstantiationRange);
121  if (!Invalid) {
122    ActiveTemplateInstantiation Inst;
123    Inst.Kind
124      = ActiveTemplateInstantiation::DefaultTemplateArgumentInstantiation;
125    Inst.PointOfInstantiation = PointOfInstantiation;
126    Inst.Entity = reinterpret_cast<uintptr_t>(Template);
127    Inst.TemplateArgs = TemplateArgs;
128    Inst.NumTemplateArgs = NumTemplateArgs;
129    Inst.InstantiationRange = InstantiationRange;
130    SemaRef.ActiveTemplateInstantiations.push_back(Inst);
131    Invalid = false;
132  }
133}
134
135Sema::InstantiatingTemplate::InstantiatingTemplate(Sema &SemaRef,
136                                         SourceLocation PointOfInstantiation,
137                                      FunctionTemplateDecl *FunctionTemplate,
138                                        const TemplateArgument *TemplateArgs,
139                                                   unsigned NumTemplateArgs,
140                         ActiveTemplateInstantiation::InstantiationKind Kind,
141                                              SourceRange InstantiationRange)
142: SemaRef(SemaRef) {
143
144  Invalid = CheckInstantiationDepth(PointOfInstantiation,
145                                    InstantiationRange);
146  if (!Invalid) {
147    ActiveTemplateInstantiation Inst;
148    Inst.Kind = Kind;
149    Inst.PointOfInstantiation = PointOfInstantiation;
150    Inst.Entity = reinterpret_cast<uintptr_t>(FunctionTemplate);
151    Inst.TemplateArgs = TemplateArgs;
152    Inst.NumTemplateArgs = NumTemplateArgs;
153    Inst.InstantiationRange = InstantiationRange;
154    SemaRef.ActiveTemplateInstantiations.push_back(Inst);
155    Invalid = false;
156  }
157}
158
159Sema::InstantiatingTemplate::InstantiatingTemplate(Sema &SemaRef,
160                                         SourceLocation PointOfInstantiation,
161                          ClassTemplatePartialSpecializationDecl *PartialSpec,
162                                         const TemplateArgument *TemplateArgs,
163                                         unsigned NumTemplateArgs,
164                                         SourceRange InstantiationRange)
165  : SemaRef(SemaRef) {
166
167  Invalid = CheckInstantiationDepth(PointOfInstantiation,
168                                    InstantiationRange);
169  if (!Invalid) {
170    ActiveTemplateInstantiation Inst;
171    Inst.Kind
172      = ActiveTemplateInstantiation::DeducedTemplateArgumentSubstitution;
173    Inst.PointOfInstantiation = PointOfInstantiation;
174    Inst.Entity = reinterpret_cast<uintptr_t>(PartialSpec);
175    Inst.TemplateArgs = TemplateArgs;
176    Inst.NumTemplateArgs = NumTemplateArgs;
177    Inst.InstantiationRange = InstantiationRange;
178    SemaRef.ActiveTemplateInstantiations.push_back(Inst);
179    Invalid = false;
180  }
181}
182
183Sema::InstantiatingTemplate::InstantiatingTemplate(Sema &SemaRef,
184                                          SourceLocation PointOfInstantation,
185                                          ParmVarDecl *Param,
186                                          const TemplateArgument *TemplateArgs,
187                                          unsigned NumTemplateArgs,
188                                          SourceRange InstantiationRange)
189  : SemaRef(SemaRef) {
190
191  Invalid = CheckInstantiationDepth(PointOfInstantation, InstantiationRange);
192
193  if (!Invalid) {
194    ActiveTemplateInstantiation Inst;
195    Inst.Kind
196      = ActiveTemplateInstantiation::DefaultFunctionArgumentInstantiation;
197    Inst.PointOfInstantiation = PointOfInstantation;
198    Inst.Entity = reinterpret_cast<uintptr_t>(Param);
199    Inst.TemplateArgs = TemplateArgs;
200    Inst.NumTemplateArgs = NumTemplateArgs;
201    Inst.InstantiationRange = InstantiationRange;
202    SemaRef.ActiveTemplateInstantiations.push_back(Inst);
203    Invalid = false;
204  }
205}
206
207void Sema::InstantiatingTemplate::Clear() {
208  if (!Invalid) {
209    SemaRef.ActiveTemplateInstantiations.pop_back();
210    Invalid = true;
211  }
212}
213
214bool Sema::InstantiatingTemplate::CheckInstantiationDepth(
215                                        SourceLocation PointOfInstantiation,
216                                           SourceRange InstantiationRange) {
217  if (SemaRef.ActiveTemplateInstantiations.size()
218       <= SemaRef.getLangOptions().InstantiationDepth)
219    return false;
220
221  SemaRef.Diag(PointOfInstantiation,
222               diag::err_template_recursion_depth_exceeded)
223    << SemaRef.getLangOptions().InstantiationDepth
224    << InstantiationRange;
225  SemaRef.Diag(PointOfInstantiation, diag::note_template_recursion_depth)
226    << SemaRef.getLangOptions().InstantiationDepth;
227  return true;
228}
229
230/// \brief Prints the current instantiation stack through a series of
231/// notes.
232void Sema::PrintInstantiationStack() {
233  // FIXME: In all of these cases, we need to show the template arguments
234  for (llvm::SmallVector<ActiveTemplateInstantiation, 16>::reverse_iterator
235         Active = ActiveTemplateInstantiations.rbegin(),
236         ActiveEnd = ActiveTemplateInstantiations.rend();
237       Active != ActiveEnd;
238       ++Active) {
239    switch (Active->Kind) {
240    case ActiveTemplateInstantiation::TemplateInstantiation: {
241      Decl *D = reinterpret_cast<Decl *>(Active->Entity);
242      if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(D)) {
243        unsigned DiagID = diag::note_template_member_class_here;
244        if (isa<ClassTemplateSpecializationDecl>(Record))
245          DiagID = diag::note_template_class_instantiation_here;
246        Diags.Report(FullSourceLoc(Active->PointOfInstantiation, SourceMgr),
247                     DiagID)
248          << Context.getTypeDeclType(Record)
249          << Active->InstantiationRange;
250      } else if (FunctionDecl *Function = dyn_cast<FunctionDecl>(D)) {
251        unsigned DiagID;
252        if (Function->getPrimaryTemplate())
253          DiagID = diag::note_function_template_spec_here;
254        else
255          DiagID = diag::note_template_member_function_here;
256        Diags.Report(FullSourceLoc(Active->PointOfInstantiation, SourceMgr),
257                     DiagID)
258          << Function
259          << Active->InstantiationRange;
260      } else {
261        Diags.Report(FullSourceLoc(Active->PointOfInstantiation, SourceMgr),
262                     diag::note_template_static_data_member_def_here)
263          << cast<VarDecl>(D)
264          << Active->InstantiationRange;
265      }
266      break;
267    }
268
269    case ActiveTemplateInstantiation::DefaultTemplateArgumentInstantiation: {
270      TemplateDecl *Template = cast<TemplateDecl>((Decl *)Active->Entity);
271      std::string TemplateArgsStr
272        = TemplateSpecializationType::PrintTemplateArgumentList(
273                                                         Active->TemplateArgs,
274                                                      Active->NumTemplateArgs,
275                                                      Context.PrintingPolicy);
276      Diags.Report(FullSourceLoc(Active->PointOfInstantiation, SourceMgr),
277                   diag::note_default_arg_instantiation_here)
278        << (Template->getNameAsString() + TemplateArgsStr)
279        << Active->InstantiationRange;
280      break;
281    }
282
283    case ActiveTemplateInstantiation::ExplicitTemplateArgumentSubstitution: {
284      FunctionTemplateDecl *FnTmpl
285        = cast<FunctionTemplateDecl>((Decl *)Active->Entity);
286      Diags.Report(FullSourceLoc(Active->PointOfInstantiation, SourceMgr),
287                   diag::note_explicit_template_arg_substitution_here)
288        << FnTmpl << Active->InstantiationRange;
289      break;
290    }
291
292    case ActiveTemplateInstantiation::DeducedTemplateArgumentSubstitution:
293      if (ClassTemplatePartialSpecializationDecl *PartialSpec
294            = dyn_cast<ClassTemplatePartialSpecializationDecl>(
295                                                    (Decl *)Active->Entity)) {
296        Diags.Report(FullSourceLoc(Active->PointOfInstantiation, SourceMgr),
297                     diag::note_partial_spec_deduct_instantiation_here)
298          << Context.getTypeDeclType(PartialSpec)
299          << Active->InstantiationRange;
300      } else {
301        FunctionTemplateDecl *FnTmpl
302          = cast<FunctionTemplateDecl>((Decl *)Active->Entity);
303        Diags.Report(FullSourceLoc(Active->PointOfInstantiation, SourceMgr),
304                     diag::note_function_template_deduction_instantiation_here)
305          << FnTmpl << Active->InstantiationRange;
306      }
307      break;
308
309    case ActiveTemplateInstantiation::DefaultFunctionArgumentInstantiation: {
310      ParmVarDecl *Param = cast<ParmVarDecl>((Decl *)Active->Entity);
311      FunctionDecl *FD = cast<FunctionDecl>(Param->getDeclContext());
312
313      std::string TemplateArgsStr
314        = TemplateSpecializationType::PrintTemplateArgumentList(
315                                                         Active->TemplateArgs,
316                                                      Active->NumTemplateArgs,
317                                                      Context.PrintingPolicy);
318      Diags.Report(FullSourceLoc(Active->PointOfInstantiation, SourceMgr),
319                   diag::note_default_function_arg_instantiation_here)
320        << (FD->getNameAsString() + TemplateArgsStr)
321        << Active->InstantiationRange;
322      break;
323    }
324
325    }
326  }
327}
328
329bool Sema::isSFINAEContext() const {
330  using llvm::SmallVector;
331  for (SmallVector<ActiveTemplateInstantiation, 16>::const_reverse_iterator
332         Active = ActiveTemplateInstantiations.rbegin(),
333         ActiveEnd = ActiveTemplateInstantiations.rend();
334       Active != ActiveEnd;
335       ++Active) {
336
337    switch(Active->Kind) {
338    case ActiveTemplateInstantiation::TemplateInstantiation:
339    case ActiveTemplateInstantiation::DefaultFunctionArgumentInstantiation:
340
341      // This is a template instantiation, so there is no SFINAE.
342      return false;
343
344    case ActiveTemplateInstantiation::DefaultTemplateArgumentInstantiation:
345      // A default template argument instantiation may or may not be a
346      // SFINAE context; look further up the stack.
347      break;
348
349    case ActiveTemplateInstantiation::ExplicitTemplateArgumentSubstitution:
350    case ActiveTemplateInstantiation::DeducedTemplateArgumentSubstitution:
351      // We're either substitution explicitly-specified template arguments
352      // or deduced template arguments, so SFINAE applies.
353      return true;
354    }
355  }
356
357  return false;
358}
359
360//===----------------------------------------------------------------------===/
361// Template Instantiation for Types
362//===----------------------------------------------------------------------===/
363namespace {
364  class VISIBILITY_HIDDEN TemplateInstantiator
365    : public TreeTransform<TemplateInstantiator> {
366    const MultiLevelTemplateArgumentList &TemplateArgs;
367    SourceLocation Loc;
368    DeclarationName Entity;
369
370  public:
371    typedef TreeTransform<TemplateInstantiator> inherited;
372
373    TemplateInstantiator(Sema &SemaRef,
374                         const MultiLevelTemplateArgumentList &TemplateArgs,
375                         SourceLocation Loc,
376                         DeclarationName Entity)
377      : inherited(SemaRef), TemplateArgs(TemplateArgs), Loc(Loc),
378        Entity(Entity) { }
379
380    /// \brief Determine whether the given type \p T has already been
381    /// transformed.
382    ///
383    /// For the purposes of template instantiation, a type has already been
384    /// transformed if it is NULL or if it is not dependent.
385    bool AlreadyTransformed(QualType T) {
386      return T.isNull() || !T->isDependentType();
387    }
388
389    /// \brief Returns the location of the entity being instantiated, if known.
390    SourceLocation getBaseLocation() { return Loc; }
391
392    /// \brief Returns the name of the entity being instantiated, if any.
393    DeclarationName getBaseEntity() { return Entity; }
394
395    /// \brief Sets the "base" location and entity when that
396    /// information is known based on another transformation.
397    void setBase(SourceLocation Loc, DeclarationName Entity) {
398      this->Loc = Loc;
399      this->Entity = Entity;
400    }
401
402    /// \brief Transform the given declaration by instantiating a reference to
403    /// this declaration.
404    Decl *TransformDecl(Decl *D);
405
406    /// \brief Transform the definition of the given declaration by
407    /// instantiating it.
408    Decl *TransformDefinition(Decl *D);
409
410    /// \bried Transform the first qualifier within a scope by instantiating the
411    /// declaration.
412    NamedDecl *TransformFirstQualifierInScope(NamedDecl *D, SourceLocation Loc);
413
414    /// \brief Rebuild the exception declaration and register the declaration
415    /// as an instantiated local.
416    VarDecl *RebuildExceptionDecl(VarDecl *ExceptionDecl, QualType T,
417                                  DeclaratorInfo *Declarator,
418                                  IdentifierInfo *Name,
419                                  SourceLocation Loc, SourceRange TypeRange);
420
421    /// \brief Check for tag mismatches when instantiating an
422    /// elaborated type.
423    QualType RebuildElaboratedType(QualType T, ElaboratedType::TagKind Tag);
424
425    Sema::OwningExprResult TransformPredefinedExpr(PredefinedExpr *E,
426                                                   bool isAddressOfOperand);
427    Sema::OwningExprResult TransformDeclRefExpr(DeclRefExpr *E,
428                                                bool isAddressOfOperand);
429
430    /// \brief Transforms a template type parameter type by performing
431    /// substitution of the corresponding template type argument.
432    QualType TransformTemplateTypeParmType(TypeLocBuilder &TLB,
433                                           TemplateTypeParmTypeLoc TL);
434  };
435}
436
437Decl *TemplateInstantiator::TransformDecl(Decl *D) {
438  if (!D)
439    return 0;
440
441  if (TemplateTemplateParmDecl *TTP = dyn_cast<TemplateTemplateParmDecl>(D)) {
442    if (TTP->getDepth() < TemplateArgs.getNumLevels()) {
443      assert(TemplateArgs(TTP->getDepth(), TTP->getPosition()).getAsDecl() &&
444             "Wrong kind of template template argument");
445      return cast<TemplateDecl>(TemplateArgs(TTP->getDepth(),
446                                             TTP->getPosition()).getAsDecl());
447    }
448
449    // If the corresponding template argument is NULL or non-existent, it's
450    // because we are performing instantiation from explicitly-specified
451    // template arguments in a function template, but there were some
452    // arguments left unspecified.
453    if (!TemplateArgs.hasTemplateArgument(TTP->getDepth(),
454                                          TTP->getPosition()))
455      return D;
456
457    // FIXME: Implement depth reduction of template template parameters
458    assert(false &&
459      "Reducing depth of template template parameters is not yet implemented");
460  }
461
462  return SemaRef.FindInstantiatedDecl(cast<NamedDecl>(D), TemplateArgs);
463}
464
465Decl *TemplateInstantiator::TransformDefinition(Decl *D) {
466  Decl *Inst = getSema().SubstDecl(D, getSema().CurContext, TemplateArgs);
467  if (!Inst)
468    return 0;
469
470  getSema().CurrentInstantiationScope->InstantiatedLocal(D, Inst);
471  return Inst;
472}
473
474NamedDecl *
475TemplateInstantiator::TransformFirstQualifierInScope(NamedDecl *D,
476                                                     SourceLocation Loc) {
477  // If the first part of the nested-name-specifier was a template type
478  // parameter, instantiate that type parameter down to a tag type.
479  if (TemplateTypeParmDecl *TTPD = dyn_cast_or_null<TemplateTypeParmDecl>(D)) {
480    const TemplateTypeParmType *TTP
481      = cast<TemplateTypeParmType>(getSema().Context.getTypeDeclType(TTPD));
482    if (TTP->getDepth() < TemplateArgs.getNumLevels()) {
483      QualType T = TemplateArgs(TTP->getDepth(), TTP->getIndex()).getAsType();
484      if (T.isNull())
485        return cast_or_null<NamedDecl>(TransformDecl(D));
486
487      if (const TagType *Tag = T->getAs<TagType>())
488        return Tag->getDecl();
489
490      // The resulting type is not a tag; complain.
491      getSema().Diag(Loc, diag::err_nested_name_spec_non_tag) << T;
492      return 0;
493    }
494  }
495
496  return cast_or_null<NamedDecl>(TransformDecl(D));
497}
498
499VarDecl *
500TemplateInstantiator::RebuildExceptionDecl(VarDecl *ExceptionDecl,
501                                           QualType T,
502                                           DeclaratorInfo *Declarator,
503                                           IdentifierInfo *Name,
504                                           SourceLocation Loc,
505                                           SourceRange TypeRange) {
506  VarDecl *Var = inherited::RebuildExceptionDecl(ExceptionDecl, T, Declarator,
507                                                 Name, Loc, TypeRange);
508  if (Var && !Var->isInvalidDecl())
509    getSema().CurrentInstantiationScope->InstantiatedLocal(ExceptionDecl, Var);
510  return Var;
511}
512
513QualType
514TemplateInstantiator::RebuildElaboratedType(QualType T,
515                                            ElaboratedType::TagKind Tag) {
516  if (const TagType *TT = T->getAs<TagType>()) {
517    TagDecl* TD = TT->getDecl();
518
519    // FIXME: this location is very wrong;  we really need typelocs.
520    SourceLocation TagLocation = TD->getTagKeywordLoc();
521
522    // FIXME: type might be anonymous.
523    IdentifierInfo *Id = TD->getIdentifier();
524
525    // TODO: should we even warn on struct/class mismatches for this?  Seems
526    // like it's likely to produce a lot of spurious errors.
527    if (!SemaRef.isAcceptableTagRedeclaration(TD, Tag, TagLocation, *Id)) {
528      SemaRef.Diag(TagLocation, diag::err_use_with_wrong_tag)
529        << Id
530        << CodeModificationHint::CreateReplacement(SourceRange(TagLocation),
531                                                   TD->getKindName());
532      SemaRef.Diag(TD->getLocation(), diag::note_previous_use);
533    }
534  }
535
536  return TreeTransform<TemplateInstantiator>::RebuildElaboratedType(T, Tag);
537}
538
539Sema::OwningExprResult
540TemplateInstantiator::TransformPredefinedExpr(PredefinedExpr *E,
541                                              bool isAddressOfOperand) {
542  if (!E->isTypeDependent())
543    return SemaRef.Owned(E->Retain());
544
545  FunctionDecl *currentDecl = getSema().getCurFunctionDecl();
546  assert(currentDecl && "Must have current function declaration when "
547                        "instantiating.");
548
549  PredefinedExpr::IdentType IT = E->getIdentType();
550
551  unsigned Length =
552    PredefinedExpr::ComputeName(getSema().Context, IT, currentDecl).length();
553
554  llvm::APInt LengthI(32, Length + 1);
555  QualType ResTy = getSema().Context.CharTy.withConst();
556  ResTy = getSema().Context.getConstantArrayType(ResTy, LengthI,
557                                                 ArrayType::Normal, 0);
558  PredefinedExpr *PE =
559    new (getSema().Context) PredefinedExpr(E->getLocation(), ResTy, IT);
560  return getSema().Owned(PE);
561}
562
563Sema::OwningExprResult
564TemplateInstantiator::TransformDeclRefExpr(DeclRefExpr *E,
565                                           bool isAddressOfOperand) {
566  // FIXME: Clean this up a bit
567  NamedDecl *D = E->getDecl();
568  if (NonTypeTemplateParmDecl *NTTP = dyn_cast<NonTypeTemplateParmDecl>(D)) {
569    if (NTTP->getDepth() < TemplateArgs.getNumLevels()) {
570
571      // If the corresponding template argument is NULL or non-existent, it's
572      // because we are performing instantiation from explicitly-specified
573      // template arguments in a function template, but there were some
574      // arguments left unspecified.
575      if (!TemplateArgs.hasTemplateArgument(NTTP->getDepth(),
576                                            NTTP->getPosition()))
577        return SemaRef.Owned(E->Retain());
578
579      const TemplateArgument &Arg = TemplateArgs(NTTP->getDepth(),
580                                                 NTTP->getPosition());
581
582      // The template argument itself might be an expression, in which
583      // case we just return that expression.
584      if (Arg.getKind() == TemplateArgument::Expression)
585        return SemaRef.Owned(Arg.getAsExpr()->Retain());
586
587      if (Arg.getKind() == TemplateArgument::Declaration) {
588        ValueDecl *VD = cast<ValueDecl>(Arg.getAsDecl());
589
590        VD = cast_or_null<ValueDecl>(
591                              getSema().FindInstantiatedDecl(VD, TemplateArgs));
592        if (!VD)
593          return SemaRef.ExprError();
594
595        return SemaRef.BuildDeclRefExpr(VD, VD->getType(), E->getLocation(),
596                                        /*FIXME:*/false, /*FIXME:*/false);
597      }
598
599      assert(Arg.getKind() == TemplateArgument::Integral);
600      QualType T = Arg.getIntegralType();
601      if (T->isCharType() || T->isWideCharType())
602        return SemaRef.Owned(new (SemaRef.Context) CharacterLiteral(
603                                              Arg.getAsIntegral()->getZExtValue(),
604                                              T->isWideCharType(),
605                                              T,
606                                              E->getSourceRange().getBegin()));
607      if (T->isBooleanType())
608        return SemaRef.Owned(new (SemaRef.Context) CXXBoolLiteralExpr(
609                                            Arg.getAsIntegral()->getBoolValue(),
610                                            T,
611                                            E->getSourceRange().getBegin()));
612
613      assert(Arg.getAsIntegral()->getBitWidth() == SemaRef.Context.getIntWidth(T));
614      return SemaRef.Owned(new (SemaRef.Context) IntegerLiteral(
615                                                *Arg.getAsIntegral(),
616                                                T,
617                                                E->getSourceRange().getBegin()));
618    }
619
620    // We have a non-type template parameter that isn't fully substituted;
621    // FindInstantiatedDecl will find it in the local instantiation scope.
622  }
623
624  NamedDecl *InstD = SemaRef.FindInstantiatedDecl(D, TemplateArgs);
625  if (!InstD)
626    return SemaRef.ExprError();
627
628  // If we instantiated an UnresolvedUsingDecl and got back an UsingDecl,
629  // we need to get the underlying decl.
630  // FIXME: Is this correct? Maybe FindInstantiatedDecl should do this?
631  InstD = InstD->getUnderlyingDecl();
632
633  CXXScopeSpec SS;
634  NestedNameSpecifier *Qualifier = 0;
635  if (E->getQualifier()) {
636    Qualifier = TransformNestedNameSpecifier(E->getQualifier(),
637                                             E->getQualifierRange());
638    if (!Qualifier)
639      return SemaRef.ExprError();
640
641    SS.setScopeRep(Qualifier);
642    SS.setRange(E->getQualifierRange());
643  }
644
645  return SemaRef.BuildDeclarationNameExpr(E->getLocation(), InstD,
646                                          /*FIXME:*/false,
647                                          &SS,
648                                          isAddressOfOperand);
649}
650
651QualType
652TemplateInstantiator::TransformTemplateTypeParmType(TypeLocBuilder &TLB,
653                                                TemplateTypeParmTypeLoc TL) {
654  TemplateTypeParmType *T = TL.getTypePtr();
655  if (T->getDepth() < TemplateArgs.getNumLevels()) {
656    // Replace the template type parameter with its corresponding
657    // template argument.
658
659    // If the corresponding template argument is NULL or doesn't exist, it's
660    // because we are performing instantiation from explicitly-specified
661    // template arguments in a function template class, but there were some
662    // arguments left unspecified.
663    if (!TemplateArgs.hasTemplateArgument(T->getDepth(), T->getIndex())) {
664      TemplateTypeParmTypeLoc NewTL
665        = TLB.push<TemplateTypeParmTypeLoc>(TL.getType());
666      NewTL.setNameLoc(TL.getNameLoc());
667      return TL.getType();
668    }
669
670    assert(TemplateArgs(T->getDepth(), T->getIndex()).getKind()
671             == TemplateArgument::Type &&
672           "Template argument kind mismatch");
673
674    QualType Replacement
675      = TemplateArgs(T->getDepth(), T->getIndex()).getAsType();
676
677    // TODO: only do this uniquing once, at the start of instantiation.
678    QualType Result
679      = getSema().Context.getSubstTemplateTypeParmType(T, Replacement);
680    SubstTemplateTypeParmTypeLoc NewTL
681      = TLB.push<SubstTemplateTypeParmTypeLoc>(Result);
682    NewTL.setNameLoc(TL.getNameLoc());
683    return Result;
684  }
685
686  // The template type parameter comes from an inner template (e.g.,
687  // the template parameter list of a member template inside the
688  // template we are instantiating). Create a new template type
689  // parameter with the template "level" reduced by one.
690  QualType Result
691    = getSema().Context.getTemplateTypeParmType(T->getDepth()
692                                                 - TemplateArgs.getNumLevels(),
693                                                T->getIndex(),
694                                                T->isParameterPack(),
695                                                T->getName());
696  TemplateTypeParmTypeLoc NewTL = TLB.push<TemplateTypeParmTypeLoc>(Result);
697  NewTL.setNameLoc(TL.getNameLoc());
698  return Result;
699}
700
701/// \brief Perform substitution on the type T with a given set of template
702/// arguments.
703///
704/// This routine substitutes the given template arguments into the
705/// type T and produces the instantiated type.
706///
707/// \param T the type into which the template arguments will be
708/// substituted. If this type is not dependent, it will be returned
709/// immediately.
710///
711/// \param TemplateArgs the template arguments that will be
712/// substituted for the top-level template parameters within T.
713///
714/// \param Loc the location in the source code where this substitution
715/// is being performed. It will typically be the location of the
716/// declarator (if we're instantiating the type of some declaration)
717/// or the location of the type in the source code (if, e.g., we're
718/// instantiating the type of a cast expression).
719///
720/// \param Entity the name of the entity associated with a declaration
721/// being instantiated (if any). May be empty to indicate that there
722/// is no such entity (if, e.g., this is a type that occurs as part of
723/// a cast expression) or that the entity has no name (e.g., an
724/// unnamed function parameter).
725///
726/// \returns If the instantiation succeeds, the instantiated
727/// type. Otherwise, produces diagnostics and returns a NULL type.
728DeclaratorInfo *Sema::SubstType(DeclaratorInfo *T,
729                                const MultiLevelTemplateArgumentList &Args,
730                                SourceLocation Loc,
731                                DeclarationName Entity) {
732  assert(!ActiveTemplateInstantiations.empty() &&
733         "Cannot perform an instantiation without some context on the "
734         "instantiation stack");
735
736  if (!T->getType()->isDependentType())
737    return T;
738
739  TemplateInstantiator Instantiator(*this, Args, Loc, Entity);
740  return Instantiator.TransformType(T);
741}
742
743/// Deprecated form of the above.
744QualType Sema::SubstType(QualType T,
745                         const MultiLevelTemplateArgumentList &TemplateArgs,
746                         SourceLocation Loc, DeclarationName Entity) {
747  assert(!ActiveTemplateInstantiations.empty() &&
748         "Cannot perform an instantiation without some context on the "
749         "instantiation stack");
750
751  // If T is not a dependent type, there is nothing to do.
752  if (!T->isDependentType())
753    return T;
754
755  TemplateInstantiator Instantiator(*this, TemplateArgs, Loc, Entity);
756  return Instantiator.TransformType(T);
757}
758
759/// \brief Perform substitution on the base class specifiers of the
760/// given class template specialization.
761///
762/// Produces a diagnostic and returns true on error, returns false and
763/// attaches the instantiated base classes to the class template
764/// specialization if successful.
765bool
766Sema::SubstBaseSpecifiers(CXXRecordDecl *Instantiation,
767                          CXXRecordDecl *Pattern,
768                          const MultiLevelTemplateArgumentList &TemplateArgs) {
769  bool Invalid = false;
770  llvm::SmallVector<CXXBaseSpecifier*, 4> InstantiatedBases;
771  for (ClassTemplateSpecializationDecl::base_class_iterator
772         Base = Pattern->bases_begin(), BaseEnd = Pattern->bases_end();
773       Base != BaseEnd; ++Base) {
774    if (!Base->getType()->isDependentType()) {
775      InstantiatedBases.push_back(new (Context) CXXBaseSpecifier(*Base));
776      continue;
777    }
778
779    QualType BaseType = SubstType(Base->getType(),
780                                  TemplateArgs,
781                                  Base->getSourceRange().getBegin(),
782                                  DeclarationName());
783    if (BaseType.isNull()) {
784      Invalid = true;
785      continue;
786    }
787
788    if (CXXBaseSpecifier *InstantiatedBase
789          = CheckBaseSpecifier(Instantiation,
790                               Base->getSourceRange(),
791                               Base->isVirtual(),
792                               Base->getAccessSpecifierAsWritten(),
793                               BaseType,
794                               /*FIXME: Not totally accurate */
795                               Base->getSourceRange().getBegin()))
796      InstantiatedBases.push_back(InstantiatedBase);
797    else
798      Invalid = true;
799  }
800
801  if (!Invalid &&
802      AttachBaseSpecifiers(Instantiation, InstantiatedBases.data(),
803                           InstantiatedBases.size()))
804    Invalid = true;
805
806  return Invalid;
807}
808
809/// \brief Instantiate the definition of a class from a given pattern.
810///
811/// \param PointOfInstantiation The point of instantiation within the
812/// source code.
813///
814/// \param Instantiation is the declaration whose definition is being
815/// instantiated. This will be either a class template specialization
816/// or a member class of a class template specialization.
817///
818/// \param Pattern is the pattern from which the instantiation
819/// occurs. This will be either the declaration of a class template or
820/// the declaration of a member class of a class template.
821///
822/// \param TemplateArgs The template arguments to be substituted into
823/// the pattern.
824///
825/// \param TSK the kind of implicit or explicit instantiation to perform.
826///
827/// \param Complain whether to complain if the class cannot be instantiated due
828/// to the lack of a definition.
829///
830/// \returns true if an error occurred, false otherwise.
831bool
832Sema::InstantiateClass(SourceLocation PointOfInstantiation,
833                       CXXRecordDecl *Instantiation, CXXRecordDecl *Pattern,
834                       const MultiLevelTemplateArgumentList &TemplateArgs,
835                       TemplateSpecializationKind TSK,
836                       bool Complain) {
837  bool Invalid = false;
838
839  CXXRecordDecl *PatternDef
840    = cast_or_null<CXXRecordDecl>(Pattern->getDefinition(Context));
841  if (!PatternDef) {
842    if (!Complain) {
843      // Say nothing
844    } else if (Pattern == Instantiation->getInstantiatedFromMemberClass()) {
845      Diag(PointOfInstantiation,
846           diag::err_implicit_instantiate_member_undefined)
847        << Context.getTypeDeclType(Instantiation);
848      Diag(Pattern->getLocation(), diag::note_member_of_template_here);
849    } else {
850      Diag(PointOfInstantiation, diag::err_template_instantiate_undefined)
851        << (TSK != TSK_ImplicitInstantiation)
852        << Context.getTypeDeclType(Instantiation);
853      Diag(Pattern->getLocation(), diag::note_template_decl_here);
854    }
855    return true;
856  }
857  Pattern = PatternDef;
858
859  // \brief Record the point of instantiation.
860  if (MemberSpecializationInfo *MSInfo
861        = Instantiation->getMemberSpecializationInfo()) {
862    MSInfo->setTemplateSpecializationKind(TSK);
863    MSInfo->setPointOfInstantiation(PointOfInstantiation);
864  } else if (ClassTemplateSpecializationDecl *Spec
865               = dyn_cast<ClassTemplateSpecializationDecl>(Instantiation)) {
866    Spec->setTemplateSpecializationKind(TSK);
867    Spec->setPointOfInstantiation(PointOfInstantiation);
868  }
869
870  InstantiatingTemplate Inst(*this, PointOfInstantiation, Instantiation);
871  if (Inst)
872    return true;
873
874  // Enter the scope of this instantiation. We don't use
875  // PushDeclContext because we don't have a scope.
876  DeclContext *PreviousContext = CurContext;
877  CurContext = Instantiation;
878
879  // Start the definition of this instantiation.
880  Instantiation->startDefinition();
881
882  // Do substitution on the base class specifiers.
883  if (SubstBaseSpecifiers(Instantiation, Pattern, TemplateArgs))
884    Invalid = true;
885
886  llvm::SmallVector<DeclPtrTy, 4> Fields;
887  for (RecordDecl::decl_iterator Member = Pattern->decls_begin(),
888         MemberEnd = Pattern->decls_end();
889       Member != MemberEnd; ++Member) {
890    Decl *NewMember = SubstDecl(*Member, Instantiation, TemplateArgs);
891    if (NewMember) {
892      if (NewMember->isInvalidDecl())
893        Invalid = true;
894      else if (FieldDecl *Field = dyn_cast<FieldDecl>(NewMember))
895        Fields.push_back(DeclPtrTy::make(Field));
896      else if (UsingDecl *UD = dyn_cast<UsingDecl>(NewMember))
897        Instantiation->addDecl(UD);
898    } else {
899      // FIXME: Eventually, a NULL return will mean that one of the
900      // instantiations was a semantic disaster, and we'll want to set Invalid =
901      // true. For now, we expect to skip some members that we can't yet handle.
902    }
903  }
904
905  // Finish checking fields.
906  ActOnFields(0, Instantiation->getLocation(), DeclPtrTy::make(Instantiation),
907              Fields.data(), Fields.size(), SourceLocation(), SourceLocation(),
908              0);
909  if (Instantiation->isInvalidDecl())
910    Invalid = true;
911
912  // Add any implicitly-declared members that we might need.
913  if (!Invalid)
914    AddImplicitlyDeclaredMembersToClass(Instantiation);
915
916  // Exit the scope of this instantiation.
917  CurContext = PreviousContext;
918
919  if (!Invalid)
920    Consumer.HandleTagDeclDefinition(Instantiation);
921
922  return Invalid;
923}
924
925bool
926Sema::InstantiateClassTemplateSpecialization(
927                           SourceLocation PointOfInstantiation,
928                           ClassTemplateSpecializationDecl *ClassTemplateSpec,
929                           TemplateSpecializationKind TSK,
930                           bool Complain) {
931  // Perform the actual instantiation on the canonical declaration.
932  ClassTemplateSpec = cast<ClassTemplateSpecializationDecl>(
933                                         ClassTemplateSpec->getCanonicalDecl());
934
935  // Check whether we have already instantiated or specialized this class
936  // template specialization.
937  if (ClassTemplateSpec->getSpecializationKind() != TSK_Undeclared) {
938    if (ClassTemplateSpec->getSpecializationKind() ==
939          TSK_ExplicitInstantiationDeclaration &&
940        TSK == TSK_ExplicitInstantiationDefinition) {
941      // An explicit instantiation definition follows an explicit instantiation
942      // declaration (C++0x [temp.explicit]p10); go ahead and perform the
943      // explicit instantiation.
944      ClassTemplateSpec->setSpecializationKind(TSK);
945      return false;
946    }
947
948    // We can only instantiate something that hasn't already been
949    // instantiated or specialized. Fail without any diagnostics: our
950    // caller will provide an error message.
951    return true;
952  }
953
954  if (ClassTemplateSpec->isInvalidDecl())
955    return true;
956
957  ClassTemplateDecl *Template = ClassTemplateSpec->getSpecializedTemplate();
958  CXXRecordDecl *Pattern = 0;
959
960  // C++ [temp.class.spec.match]p1:
961  //   When a class template is used in a context that requires an
962  //   instantiation of the class, it is necessary to determine
963  //   whether the instantiation is to be generated using the primary
964  //   template or one of the partial specializations. This is done by
965  //   matching the template arguments of the class template
966  //   specialization with the template argument lists of the partial
967  //   specializations.
968  typedef std::pair<ClassTemplatePartialSpecializationDecl *,
969                    TemplateArgumentList *> MatchResult;
970  llvm::SmallVector<MatchResult, 4> Matched;
971  for (llvm::FoldingSet<ClassTemplatePartialSpecializationDecl>::iterator
972         Partial = Template->getPartialSpecializations().begin(),
973         PartialEnd = Template->getPartialSpecializations().end();
974       Partial != PartialEnd;
975       ++Partial) {
976    TemplateDeductionInfo Info(Context);
977    if (TemplateDeductionResult Result
978          = DeduceTemplateArguments(&*Partial,
979                                    ClassTemplateSpec->getTemplateArgs(),
980                                    Info)) {
981      // FIXME: Store the failed-deduction information for use in
982      // diagnostics, later.
983      (void)Result;
984    } else {
985      Matched.push_back(std::make_pair(&*Partial, Info.take()));
986    }
987  }
988
989  if (Matched.size() >= 1) {
990    llvm::SmallVector<MatchResult, 4>::iterator Best = Matched.begin();
991    if (Matched.size() == 1) {
992      //   -- If exactly one matching specialization is found, the
993      //      instantiation is generated from that specialization.
994      // We don't need to do anything for this.
995    } else {
996      //   -- If more than one matching specialization is found, the
997      //      partial order rules (14.5.4.2) are used to determine
998      //      whether one of the specializations is more specialized
999      //      than the others. If none of the specializations is more
1000      //      specialized than all of the other matching
1001      //      specializations, then the use of the class template is
1002      //      ambiguous and the program is ill-formed.
1003      for (llvm::SmallVector<MatchResult, 4>::iterator P = Best + 1,
1004                                                    PEnd = Matched.end();
1005           P != PEnd; ++P) {
1006        if (getMoreSpecializedPartialSpecialization(P->first, Best->first)
1007              == P->first)
1008          Best = P;
1009      }
1010
1011      // Determine if the best partial specialization is more specialized than
1012      // the others.
1013      bool Ambiguous = false;
1014      for (llvm::SmallVector<MatchResult, 4>::iterator P = Matched.begin(),
1015                                                    PEnd = Matched.end();
1016           P != PEnd; ++P) {
1017        if (P != Best &&
1018            getMoreSpecializedPartialSpecialization(P->first, Best->first)
1019              != Best->first) {
1020          Ambiguous = true;
1021          break;
1022        }
1023      }
1024
1025      if (Ambiguous) {
1026        // Partial ordering did not produce a clear winner. Complain.
1027        ClassTemplateSpec->setInvalidDecl();
1028        Diag(PointOfInstantiation, diag::err_partial_spec_ordering_ambiguous)
1029          << ClassTemplateSpec;
1030
1031        // Print the matching partial specializations.
1032        for (llvm::SmallVector<MatchResult, 4>::iterator P = Matched.begin(),
1033                                                      PEnd = Matched.end();
1034             P != PEnd; ++P)
1035          Diag(P->first->getLocation(), diag::note_partial_spec_match)
1036            << getTemplateArgumentBindingsText(P->first->getTemplateParameters(),
1037                                               *P->second);
1038
1039        return true;
1040      }
1041    }
1042
1043    // Instantiate using the best class template partial specialization.
1044    ClassTemplatePartialSpecializationDecl *OrigPartialSpec = Best->first;
1045    while (OrigPartialSpec->getInstantiatedFromMember()) {
1046      // If we've found an explicit specialization of this class template,
1047      // stop here and use that as the pattern.
1048      if (OrigPartialSpec->isMemberSpecialization())
1049        break;
1050
1051      OrigPartialSpec = OrigPartialSpec->getInstantiatedFromMember();
1052    }
1053
1054    Pattern = OrigPartialSpec;
1055    ClassTemplateSpec->setInstantiationOf(Best->first, Best->second);
1056  } else {
1057    //   -- If no matches are found, the instantiation is generated
1058    //      from the primary template.
1059    ClassTemplateDecl *OrigTemplate = Template;
1060    while (OrigTemplate->getInstantiatedFromMemberTemplate()) {
1061      // If we've found an explicit specialization of this class template,
1062      // stop here and use that as the pattern.
1063      if (OrigTemplate->isMemberSpecialization())
1064        break;
1065
1066      OrigTemplate = OrigTemplate->getInstantiatedFromMemberTemplate();
1067    }
1068
1069    Pattern = OrigTemplate->getTemplatedDecl();
1070  }
1071
1072  bool Result = InstantiateClass(PointOfInstantiation, ClassTemplateSpec,
1073                                 Pattern,
1074                                getTemplateInstantiationArgs(ClassTemplateSpec),
1075                                 TSK,
1076                                 Complain);
1077
1078  for (unsigned I = 0, N = Matched.size(); I != N; ++I) {
1079    // FIXME: Implement TemplateArgumentList::Destroy!
1080    //    if (Matched[I].first != Pattern)
1081    //      Matched[I].second->Destroy(Context);
1082  }
1083
1084  return Result;
1085}
1086
1087/// \brief Instantiates the definitions of all of the member
1088/// of the given class, which is an instantiation of a class template
1089/// or a member class of a template.
1090void
1091Sema::InstantiateClassMembers(SourceLocation PointOfInstantiation,
1092                              CXXRecordDecl *Instantiation,
1093                        const MultiLevelTemplateArgumentList &TemplateArgs,
1094                              TemplateSpecializationKind TSK) {
1095  for (DeclContext::decl_iterator D = Instantiation->decls_begin(),
1096                               DEnd = Instantiation->decls_end();
1097       D != DEnd; ++D) {
1098    bool SuppressNew = false;
1099    if (FunctionDecl *Function = dyn_cast<FunctionDecl>(*D)) {
1100      if (FunctionDecl *Pattern
1101            = Function->getInstantiatedFromMemberFunction()) {
1102        MemberSpecializationInfo *MSInfo
1103          = Function->getMemberSpecializationInfo();
1104        assert(MSInfo && "No member specialization information?");
1105        if (CheckSpecializationInstantiationRedecl(PointOfInstantiation, TSK,
1106                                                   Function,
1107                                        MSInfo->getTemplateSpecializationKind(),
1108                                              MSInfo->getPointOfInstantiation(),
1109                                                   SuppressNew) ||
1110            SuppressNew)
1111          continue;
1112
1113        if (Function->getBody())
1114          continue;
1115
1116        if (TSK == TSK_ExplicitInstantiationDefinition) {
1117          // C++0x [temp.explicit]p8:
1118          //   An explicit instantiation definition that names a class template
1119          //   specialization explicitly instantiates the class template
1120          //   specialization and is only an explicit instantiation definition
1121          //   of members whose definition is visible at the point of
1122          //   instantiation.
1123          if (!Pattern->getBody())
1124            continue;
1125
1126          Function->setTemplateSpecializationKind(TSK, PointOfInstantiation);
1127
1128          InstantiateFunctionDefinition(PointOfInstantiation, Function);
1129        } else {
1130          Function->setTemplateSpecializationKind(TSK, PointOfInstantiation);
1131        }
1132      }
1133    } else if (VarDecl *Var = dyn_cast<VarDecl>(*D)) {
1134      if (Var->isStaticDataMember()) {
1135        MemberSpecializationInfo *MSInfo = Var->getMemberSpecializationInfo();
1136        assert(MSInfo && "No member specialization information?");
1137        if (CheckSpecializationInstantiationRedecl(PointOfInstantiation, TSK,
1138                                                   Var,
1139                                        MSInfo->getTemplateSpecializationKind(),
1140                                              MSInfo->getPointOfInstantiation(),
1141                                                   SuppressNew) ||
1142            SuppressNew)
1143          continue;
1144
1145        if (TSK == TSK_ExplicitInstantiationDefinition) {
1146          // C++0x [temp.explicit]p8:
1147          //   An explicit instantiation definition that names a class template
1148          //   specialization explicitly instantiates the class template
1149          //   specialization and is only an explicit instantiation definition
1150          //   of members whose definition is visible at the point of
1151          //   instantiation.
1152          if (!Var->getInstantiatedFromStaticDataMember()
1153                                                     ->getOutOfLineDefinition())
1154            continue;
1155
1156          Var->setTemplateSpecializationKind(TSK, PointOfInstantiation);
1157          InstantiateStaticDataMemberDefinition(PointOfInstantiation, Var);
1158        } else {
1159          Var->setTemplateSpecializationKind(TSK, PointOfInstantiation);
1160        }
1161      }
1162    } else if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(*D)) {
1163      if (Record->isInjectedClassName())
1164        continue;
1165
1166      MemberSpecializationInfo *MSInfo = Record->getMemberSpecializationInfo();
1167      assert(MSInfo && "No member specialization information?");
1168      if (CheckSpecializationInstantiationRedecl(PointOfInstantiation, TSK,
1169                                                 Record,
1170                                        MSInfo->getTemplateSpecializationKind(),
1171                                              MSInfo->getPointOfInstantiation(),
1172                                                 SuppressNew) ||
1173          SuppressNew)
1174        continue;
1175
1176      CXXRecordDecl *Pattern = Record->getInstantiatedFromMemberClass();
1177      assert(Pattern && "Missing instantiated-from-template information");
1178
1179      if (!Record->getDefinition(Context)) {
1180        if (!Pattern->getDefinition(Context)) {
1181          // C++0x [temp.explicit]p8:
1182          //   An explicit instantiation definition that names a class template
1183          //   specialization explicitly instantiates the class template
1184          //   specialization and is only an explicit instantiation definition
1185          //   of members whose definition is visible at the point of
1186          //   instantiation.
1187          if (TSK == TSK_ExplicitInstantiationDeclaration) {
1188            MSInfo->setTemplateSpecializationKind(TSK);
1189            MSInfo->setPointOfInstantiation(PointOfInstantiation);
1190          }
1191
1192          continue;
1193        }
1194
1195        InstantiateClass(PointOfInstantiation, Record, Pattern,
1196                         TemplateArgs,
1197                         TSK);
1198      }
1199
1200      Pattern = cast_or_null<CXXRecordDecl>(Record->getDefinition(Context));
1201      if (Pattern)
1202        InstantiateClassMembers(PointOfInstantiation, Pattern, TemplateArgs,
1203                                TSK);
1204    }
1205  }
1206}
1207
1208/// \brief Instantiate the definitions of all of the members of the
1209/// given class template specialization, which was named as part of an
1210/// explicit instantiation.
1211void
1212Sema::InstantiateClassTemplateSpecializationMembers(
1213                                           SourceLocation PointOfInstantiation,
1214                            ClassTemplateSpecializationDecl *ClassTemplateSpec,
1215                                               TemplateSpecializationKind TSK) {
1216  // C++0x [temp.explicit]p7:
1217  //   An explicit instantiation that names a class template
1218  //   specialization is an explicit instantion of the same kind
1219  //   (declaration or definition) of each of its members (not
1220  //   including members inherited from base classes) that has not
1221  //   been previously explicitly specialized in the translation unit
1222  //   containing the explicit instantiation, except as described
1223  //   below.
1224  InstantiateClassMembers(PointOfInstantiation, ClassTemplateSpec,
1225                          getTemplateInstantiationArgs(ClassTemplateSpec),
1226                          TSK);
1227}
1228
1229Sema::OwningStmtResult
1230Sema::SubstStmt(Stmt *S, const MultiLevelTemplateArgumentList &TemplateArgs) {
1231  if (!S)
1232    return Owned(S);
1233
1234  TemplateInstantiator Instantiator(*this, TemplateArgs,
1235                                    SourceLocation(),
1236                                    DeclarationName());
1237  return Instantiator.TransformStmt(S);
1238}
1239
1240Sema::OwningExprResult
1241Sema::SubstExpr(Expr *E, const MultiLevelTemplateArgumentList &TemplateArgs) {
1242  if (!E)
1243    return Owned(E);
1244
1245  TemplateInstantiator Instantiator(*this, TemplateArgs,
1246                                    SourceLocation(),
1247                                    DeclarationName());
1248  return Instantiator.TransformExpr(E);
1249}
1250
1251/// \brief Do template substitution on a nested-name-specifier.
1252NestedNameSpecifier *
1253Sema::SubstNestedNameSpecifier(NestedNameSpecifier *NNS,
1254                               SourceRange Range,
1255                         const MultiLevelTemplateArgumentList &TemplateArgs) {
1256  TemplateInstantiator Instantiator(*this, TemplateArgs, Range.getBegin(),
1257                                    DeclarationName());
1258  return Instantiator.TransformNestedNameSpecifier(NNS, Range);
1259}
1260
1261TemplateName
1262Sema::SubstTemplateName(TemplateName Name, SourceLocation Loc,
1263                        const MultiLevelTemplateArgumentList &TemplateArgs) {
1264  TemplateInstantiator Instantiator(*this, TemplateArgs, Loc,
1265                                    DeclarationName());
1266  return Instantiator.TransformTemplateName(Name);
1267}
1268
1269bool Sema::Subst(const TemplateArgumentLoc &Input, TemplateArgumentLoc &Output,
1270                 const MultiLevelTemplateArgumentList &TemplateArgs) {
1271  TemplateInstantiator Instantiator(*this, TemplateArgs, SourceLocation(),
1272                                    DeclarationName());
1273
1274  return Instantiator.TransformTemplateArgument(Input, Output);
1275}
1276