ASTImporter.cpp revision 83a230c83a54190366138c1a4f4310ef838b88fc 
1//===--- ASTImporter.cpp - Importing ASTs from other Contexts ---*- C++ -*-===//
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//
10//  This file defines the ASTImporter class which imports AST nodes from one
11//  context into another context.
12//
13//===----------------------------------------------------------------------===//
14#include "clang/AST/ASTImporter.h"
15
16#include "clang/AST/ASTContext.h"
17#include "clang/AST/ASTDiagnostic.h"
18#include "clang/AST/DeclCXX.h"
19#include "clang/AST/DeclObjC.h"
20#include "clang/AST/DeclVisitor.h"
21#include "clang/AST/StmtVisitor.h"
22#include "clang/AST/TypeLoc.h"
23#include "clang/AST/TypeVisitor.h"
24#include "clang/Basic/FileManager.h"
25#include "clang/Basic/SourceManager.h"
26#include "llvm/Support/MemoryBuffer.h"
27#include <deque>
28
29using namespace clang;
30
31namespace {
32  class ASTNodeImporter : public TypeVisitor<ASTNodeImporter, QualType>,
33                          public DeclVisitor<ASTNodeImporter, Decl *>,
34                          public StmtVisitor<ASTNodeImporter, Stmt *> {
35    ASTImporter &Importer;
36
37  public:
38    explicit ASTNodeImporter(ASTImporter &Importer) : Importer(Importer) { }
39
40    using TypeVisitor<ASTNodeImporter, QualType>::Visit;
41    using DeclVisitor<ASTNodeImporter, Decl *>::Visit;
42    using StmtVisitor<ASTNodeImporter, Stmt *>::Visit;
43
44    // Importing types
45    QualType VisitType(Type *T);
46    QualType VisitBuiltinType(BuiltinType *T);
47    QualType VisitComplexType(ComplexType *T);
48    QualType VisitPointerType(PointerType *T);
49    QualType VisitBlockPointerType(BlockPointerType *T);
50    QualType VisitLValueReferenceType(LValueReferenceType *T);
51    QualType VisitRValueReferenceType(RValueReferenceType *T);
52    QualType VisitMemberPointerType(MemberPointerType *T);
53    QualType VisitConstantArrayType(ConstantArrayType *T);
54    QualType VisitIncompleteArrayType(IncompleteArrayType *T);
55    QualType VisitVariableArrayType(VariableArrayType *T);
56    // FIXME: DependentSizedArrayType
57    // FIXME: DependentSizedExtVectorType
58    QualType VisitVectorType(VectorType *T);
59    QualType VisitExtVectorType(ExtVectorType *T);
60    QualType VisitFunctionNoProtoType(FunctionNoProtoType *T);
61    QualType VisitFunctionProtoType(FunctionProtoType *T);
62    // FIXME: UnresolvedUsingType
63    QualType VisitTypedefType(TypedefType *T);
64    QualType VisitTypeOfExprType(TypeOfExprType *T);
65    // FIXME: DependentTypeOfExprType
66    QualType VisitTypeOfType(TypeOfType *T);
67    QualType VisitDecltypeType(DecltypeType *T);
68    // FIXME: DependentDecltypeType
69    QualType VisitRecordType(RecordType *T);
70    QualType VisitEnumType(EnumType *T);
71    // FIXME: TemplateTypeParmType
72    // FIXME: SubstTemplateTypeParmType
73    // FIXME: TemplateSpecializationType
74    QualType VisitElaboratedType(ElaboratedType *T);
75    // FIXME: DependentNameType
76    QualType VisitObjCInterfaceType(ObjCInterfaceType *T);
77    QualType VisitObjCObjectType(ObjCObjectType *T);
78    QualType VisitObjCObjectPointerType(ObjCObjectPointerType *T);
79
80    // Importing declarations
81    bool ImportDeclParts(NamedDecl *D, DeclContext *&DC,
82                         DeclContext *&LexicalDC, DeclarationName &Name,
83                         SourceLocation &Loc);
84    void ImportDeclContext(DeclContext *FromDC);
85    bool IsStructuralMatch(RecordDecl *FromRecord, RecordDecl *ToRecord);
86    bool IsStructuralMatch(EnumDecl *FromEnum, EnumDecl *ToRecord);
87    Decl *VisitDecl(Decl *D);
88    Decl *VisitNamespaceDecl(NamespaceDecl *D);
89    Decl *VisitTypedefDecl(TypedefDecl *D);
90    Decl *VisitEnumDecl(EnumDecl *D);
91    Decl *VisitRecordDecl(RecordDecl *D);
92    Decl *VisitEnumConstantDecl(EnumConstantDecl *D);
93    Decl *VisitFunctionDecl(FunctionDecl *D);
94    Decl *VisitCXXMethodDecl(CXXMethodDecl *D);
95    Decl *VisitCXXConstructorDecl(CXXConstructorDecl *D);
96    Decl *VisitCXXDestructorDecl(CXXDestructorDecl *D);
97    Decl *VisitCXXConversionDecl(CXXConversionDecl *D);
98    Decl *VisitFieldDecl(FieldDecl *D);
99    Decl *VisitObjCIvarDecl(ObjCIvarDecl *D);
100    Decl *VisitVarDecl(VarDecl *D);
101    Decl *VisitImplicitParamDecl(ImplicitParamDecl *D);
102    Decl *VisitParmVarDecl(ParmVarDecl *D);
103    Decl *VisitObjCMethodDecl(ObjCMethodDecl *D);
104    Decl *VisitObjCCategoryDecl(ObjCCategoryDecl *D);
105    Decl *VisitObjCProtocolDecl(ObjCProtocolDecl *D);
106    Decl *VisitObjCInterfaceDecl(ObjCInterfaceDecl *D);
107    Decl *VisitObjCPropertyDecl(ObjCPropertyDecl *D);
108    Decl *VisitObjCForwardProtocolDecl(ObjCForwardProtocolDecl *D);
109    Decl *VisitObjCClassDecl(ObjCClassDecl *D);
110
111    // Importing statements
112    Stmt *VisitStmt(Stmt *S);
113
114    // Importing expressions
115    Expr *VisitExpr(Expr *E);
116    Expr *VisitDeclRefExpr(DeclRefExpr *E);
117    Expr *VisitIntegerLiteral(IntegerLiteral *E);
118    Expr *VisitCharacterLiteral(CharacterLiteral *E);
119    Expr *VisitParenExpr(ParenExpr *E);
120    Expr *VisitUnaryOperator(UnaryOperator *E);
121    Expr *VisitSizeOfAlignOfExpr(SizeOfAlignOfExpr *E);
122    Expr *VisitBinaryOperator(BinaryOperator *E);
123    Expr *VisitCompoundAssignOperator(CompoundAssignOperator *E);
124    Expr *VisitImplicitCastExpr(ImplicitCastExpr *E);
125    Expr *VisitCStyleCastExpr(CStyleCastExpr *E);
126  };
127}
128
129//----------------------------------------------------------------------------
130// Structural Equivalence
131//----------------------------------------------------------------------------
132
133namespace {
134  struct StructuralEquivalenceContext {
135    /// \brief AST contexts for which we are checking structural equivalence.
136    ASTContext &C1, &C2;
137
138    /// \brief Diagnostic object used to emit diagnostics.
139    Diagnostic &Diags;
140
141    /// \brief The set of "tentative" equivalences between two canonical
142    /// declarations, mapping from a declaration in the first context to the
143    /// declaration in the second context that we believe to be equivalent.
144    llvm::DenseMap<Decl *, Decl *> TentativeEquivalences;
145
146    /// \brief Queue of declarations in the first context whose equivalence
147    /// with a declaration in the second context still needs to be verified.
148    std::deque<Decl *> DeclsToCheck;
149
150    /// \brief Declaration (from, to) pairs that are known not to be equivalent
151    /// (which we have already complained about).
152    llvm::DenseSet<std::pair<Decl *, Decl *> > &NonEquivalentDecls;
153
154    /// \brief Whether we're being strict about the spelling of types when
155    /// unifying two types.
156    bool StrictTypeSpelling;
157
158    StructuralEquivalenceContext(ASTContext &C1, ASTContext &C2,
159                                 Diagnostic &Diags,
160               llvm::DenseSet<std::pair<Decl *, Decl *> > &NonEquivalentDecls,
161                                 bool StrictTypeSpelling = false)
162      : C1(C1), C2(C2), Diags(Diags), NonEquivalentDecls(NonEquivalentDecls),
163        StrictTypeSpelling(StrictTypeSpelling) { }
164
165    /// \brief Determine whether the two declarations are structurally
166    /// equivalent.
167    bool IsStructurallyEquivalent(Decl *D1, Decl *D2);
168
169    /// \brief Determine whether the two types are structurally equivalent.
170    bool IsStructurallyEquivalent(QualType T1, QualType T2);
171
172  private:
173    /// \brief Finish checking all of the structural equivalences.
174    ///
175    /// \returns true if an error occurred, false otherwise.
176    bool Finish();
177
178  public:
179    DiagnosticBuilder Diag1(SourceLocation Loc, unsigned DiagID) {
180      return Diags.Report(FullSourceLoc(Loc, C1.getSourceManager()), DiagID);
181    }
182
183    DiagnosticBuilder Diag2(SourceLocation Loc, unsigned DiagID) {
184      return Diags.Report(FullSourceLoc(Loc, C2.getSourceManager()), DiagID);
185    }
186  };
187}
188
189static bool IsStructurallyEquivalent(StructuralEquivalenceContext &Context,
190                                     QualType T1, QualType T2);
191static bool IsStructurallyEquivalent(StructuralEquivalenceContext &Context,
192                                     Decl *D1, Decl *D2);
193
194/// \brief Determine if two APInts have the same value, after zero-extending
195/// one of them (if needed!) to ensure that the bit-widths match.
196static bool IsSameValue(const llvm::APInt &I1, const llvm::APInt &I2) {
197  if (I1.getBitWidth() == I2.getBitWidth())
198    return I1 == I2;
199
200  if (I1.getBitWidth() > I2.getBitWidth())
201    return I1 == llvm::APInt(I2).zext(I1.getBitWidth());
202
203  return llvm::APInt(I1).zext(I2.getBitWidth()) == I2;
204}
205
206/// \brief Determine if two APSInts have the same value, zero- or sign-extending
207/// as needed.
208static bool IsSameValue(const llvm::APSInt &I1, const llvm::APSInt &I2) {
209  if (I1.getBitWidth() == I2.getBitWidth() && I1.isSigned() == I2.isSigned())
210    return I1 == I2;
211
212  // Check for a bit-width mismatch.
213  if (I1.getBitWidth() > I2.getBitWidth())
214    return IsSameValue(I1, llvm::APSInt(I2).extend(I1.getBitWidth()));
215  else if (I2.getBitWidth() > I1.getBitWidth())
216    return IsSameValue(llvm::APSInt(I1).extend(I2.getBitWidth()), I2);
217
218  // We have a signedness mismatch. Turn the signed value into an unsigned
219  // value.
220  if (I1.isSigned()) {
221    if (I1.isNegative())
222      return false;
223
224    return llvm::APSInt(I1, true) == I2;
225  }
226
227  if (I2.isNegative())
228    return false;
229
230  return I1 == llvm::APSInt(I2, true);
231}
232
233/// \brief Determine structural equivalence of two expressions.
234static bool IsStructurallyEquivalent(StructuralEquivalenceContext &Context,
235                                     Expr *E1, Expr *E2) {
236  if (!E1 || !E2)
237    return E1 == E2;
238
239  // FIXME: Actually perform a structural comparison!
240  return true;
241}
242
243/// \brief Determine whether two identifiers are equivalent.
244static bool IsStructurallyEquivalent(const IdentifierInfo *Name1,
245                                     const IdentifierInfo *Name2) {
246  if (!Name1 || !Name2)
247    return Name1 == Name2;
248
249  return Name1->getName() == Name2->getName();
250}
251
252/// \brief Determine whether two nested-name-specifiers are equivalent.
253static bool IsStructurallyEquivalent(StructuralEquivalenceContext &Context,
254                                     NestedNameSpecifier *NNS1,
255                                     NestedNameSpecifier *NNS2) {
256  // FIXME: Implement!
257  return true;
258}
259
260/// \brief Determine whether two template arguments are equivalent.
261static bool IsStructurallyEquivalent(StructuralEquivalenceContext &Context,
262                                     const TemplateArgument &Arg1,
263                                     const TemplateArgument &Arg2) {
264  // FIXME: Implement!
265  return true;
266}
267
268/// \brief Determine structural equivalence for the common part of array
269/// types.
270static bool IsArrayStructurallyEquivalent(StructuralEquivalenceContext &Context,
271                                          const ArrayType *Array1,
272                                          const ArrayType *Array2) {
273  if (!IsStructurallyEquivalent(Context,
274                                Array1->getElementType(),
275                                Array2->getElementType()))
276    return false;
277  if (Array1->getSizeModifier() != Array2->getSizeModifier())
278    return false;
279  if (Array1->getIndexTypeQualifiers() != Array2->getIndexTypeQualifiers())
280    return false;
281
282  return true;
283}
284
285/// \brief Determine structural equivalence of two types.
286static bool IsStructurallyEquivalent(StructuralEquivalenceContext &Context,
287                                     QualType T1, QualType T2) {
288  if (T1.isNull() || T2.isNull())
289    return T1.isNull() && T2.isNull();
290
291  if (!Context.StrictTypeSpelling) {
292    // We aren't being strict about token-to-token equivalence of types,
293    // so map down to the canonical type.
294    T1 = Context.C1.getCanonicalType(T1);
295    T2 = Context.C2.getCanonicalType(T2);
296  }
297
298  if (T1.getQualifiers() != T2.getQualifiers())
299    return false;
300
301  Type::TypeClass TC = T1->getTypeClass();
302
303  if (T1->getTypeClass() != T2->getTypeClass()) {
304    // Compare function types with prototypes vs. without prototypes as if
305    // both did not have prototypes.
306    if (T1->getTypeClass() == Type::FunctionProto &&
307        T2->getTypeClass() == Type::FunctionNoProto)
308      TC = Type::FunctionNoProto;
309    else if (T1->getTypeClass() == Type::FunctionNoProto &&
310             T2->getTypeClass() == Type::FunctionProto)
311      TC = Type::FunctionNoProto;
312    else
313      return false;
314  }
315
316  switch (TC) {
317  case Type::Builtin:
318    // FIXME: Deal with Char_S/Char_U.
319    if (cast<BuiltinType>(T1)->getKind() != cast<BuiltinType>(T2)->getKind())
320      return false;
321    break;
322
323  case Type::Complex:
324    if (!IsStructurallyEquivalent(Context,
325                                  cast<ComplexType>(T1)->getElementType(),
326                                  cast<ComplexType>(T2)->getElementType()))
327      return false;
328    break;
329
330  case Type::Pointer:
331    if (!IsStructurallyEquivalent(Context,
332                                  cast<PointerType>(T1)->getPointeeType(),
333                                  cast<PointerType>(T2)->getPointeeType()))
334      return false;
335    break;
336
337  case Type::BlockPointer:
338    if (!IsStructurallyEquivalent(Context,
339                                  cast<BlockPointerType>(T1)->getPointeeType(),
340                                  cast<BlockPointerType>(T2)->getPointeeType()))
341      return false;
342    break;
343
344  case Type::LValueReference:
345  case Type::RValueReference: {
346    const ReferenceType *Ref1 = cast<ReferenceType>(T1);
347    const ReferenceType *Ref2 = cast<ReferenceType>(T2);
348    if (Ref1->isSpelledAsLValue() != Ref2->isSpelledAsLValue())
349      return false;
350    if (Ref1->isInnerRef() != Ref2->isInnerRef())
351      return false;
352    if (!IsStructurallyEquivalent(Context,
353                                  Ref1->getPointeeTypeAsWritten(),
354                                  Ref2->getPointeeTypeAsWritten()))
355      return false;
356    break;
357  }
358
359  case Type::MemberPointer: {
360    const MemberPointerType *MemPtr1 = cast<MemberPointerType>(T1);
361    const MemberPointerType *MemPtr2 = cast<MemberPointerType>(T2);
362    if (!IsStructurallyEquivalent(Context,
363                                  MemPtr1->getPointeeType(),
364                                  MemPtr2->getPointeeType()))
365      return false;
366    if (!IsStructurallyEquivalent(Context,
367                                  QualType(MemPtr1->getClass(), 0),
368                                  QualType(MemPtr2->getClass(), 0)))
369      return false;
370    break;
371  }
372
373  case Type::ConstantArray: {
374    const ConstantArrayType *Array1 = cast<ConstantArrayType>(T1);
375    const ConstantArrayType *Array2 = cast<ConstantArrayType>(T2);
376    if (!IsSameValue(Array1->getSize(), Array2->getSize()))
377      return false;
378
379    if (!IsArrayStructurallyEquivalent(Context, Array1, Array2))
380      return false;
381    break;
382  }
383
384  case Type::IncompleteArray:
385    if (!IsArrayStructurallyEquivalent(Context,
386                                       cast<ArrayType>(T1),
387                                       cast<ArrayType>(T2)))
388      return false;
389    break;
390
391  case Type::VariableArray: {
392    const VariableArrayType *Array1 = cast<VariableArrayType>(T1);
393    const VariableArrayType *Array2 = cast<VariableArrayType>(T2);
394    if (!IsStructurallyEquivalent(Context,
395                                  Array1->getSizeExpr(), Array2->getSizeExpr()))
396      return false;
397
398    if (!IsArrayStructurallyEquivalent(Context, Array1, Array2))
399      return false;
400
401    break;
402  }
403
404  case Type::DependentSizedArray: {
405    const DependentSizedArrayType *Array1 = cast<DependentSizedArrayType>(T1);
406    const DependentSizedArrayType *Array2 = cast<DependentSizedArrayType>(T2);
407    if (!IsStructurallyEquivalent(Context,
408                                  Array1->getSizeExpr(), Array2->getSizeExpr()))
409      return false;
410
411    if (!IsArrayStructurallyEquivalent(Context, Array1, Array2))
412      return false;
413
414    break;
415  }
416
417  case Type::DependentSizedExtVector: {
418    const DependentSizedExtVectorType *Vec1
419      = cast<DependentSizedExtVectorType>(T1);
420    const DependentSizedExtVectorType *Vec2
421      = cast<DependentSizedExtVectorType>(T2);
422    if (!IsStructurallyEquivalent(Context,
423                                  Vec1->getSizeExpr(), Vec2->getSizeExpr()))
424      return false;
425    if (!IsStructurallyEquivalent(Context,
426                                  Vec1->getElementType(),
427                                  Vec2->getElementType()))
428      return false;
429    break;
430  }
431
432  case Type::Vector:
433  case Type::ExtVector: {
434    const VectorType *Vec1 = cast<VectorType>(T1);
435    const VectorType *Vec2 = cast<VectorType>(T2);
436    if (!IsStructurallyEquivalent(Context,
437                                  Vec1->getElementType(),
438                                  Vec2->getElementType()))
439      return false;
440    if (Vec1->getNumElements() != Vec2->getNumElements())
441      return false;
442    if (Vec1->isAltiVec() != Vec2->isAltiVec())
443      return false;
444    if (Vec1->isPixel() != Vec2->isPixel())
445      return false;
446    break;
447  }
448
449  case Type::FunctionProto: {
450    const FunctionProtoType *Proto1 = cast<FunctionProtoType>(T1);
451    const FunctionProtoType *Proto2 = cast<FunctionProtoType>(T2);
452    if (Proto1->getNumArgs() != Proto2->getNumArgs())
453      return false;
454    for (unsigned I = 0, N = Proto1->getNumArgs(); I != N; ++I) {
455      if (!IsStructurallyEquivalent(Context,
456                                    Proto1->getArgType(I),
457                                    Proto2->getArgType(I)))
458        return false;
459    }
460    if (Proto1->isVariadic() != Proto2->isVariadic())
461      return false;
462    if (Proto1->hasExceptionSpec() != Proto2->hasExceptionSpec())
463      return false;
464    if (Proto1->hasAnyExceptionSpec() != Proto2->hasAnyExceptionSpec())
465      return false;
466    if (Proto1->getNumExceptions() != Proto2->getNumExceptions())
467      return false;
468    for (unsigned I = 0, N = Proto1->getNumExceptions(); I != N; ++I) {
469      if (!IsStructurallyEquivalent(Context,
470                                    Proto1->getExceptionType(I),
471                                    Proto2->getExceptionType(I)))
472        return false;
473    }
474    if (Proto1->getTypeQuals() != Proto2->getTypeQuals())
475      return false;
476
477    // Fall through to check the bits common with FunctionNoProtoType.
478  }
479
480  case Type::FunctionNoProto: {
481    const FunctionType *Function1 = cast<FunctionType>(T1);
482    const FunctionType *Function2 = cast<FunctionType>(T2);
483    if (!IsStructurallyEquivalent(Context,
484                                  Function1->getResultType(),
485                                  Function2->getResultType()))
486      return false;
487      if (Function1->getExtInfo() != Function2->getExtInfo())
488        return false;
489    break;
490  }
491
492  case Type::UnresolvedUsing:
493    if (!IsStructurallyEquivalent(Context,
494                                  cast<UnresolvedUsingType>(T1)->getDecl(),
495                                  cast<UnresolvedUsingType>(T2)->getDecl()))
496      return false;
497
498    break;
499
500  case Type::Typedef:
501    if (!IsStructurallyEquivalent(Context,
502                                  cast<TypedefType>(T1)->getDecl(),
503                                  cast<TypedefType>(T2)->getDecl()))
504      return false;
505    break;
506
507  case Type::TypeOfExpr:
508    if (!IsStructurallyEquivalent(Context,
509                                cast<TypeOfExprType>(T1)->getUnderlyingExpr(),
510                                cast<TypeOfExprType>(T2)->getUnderlyingExpr()))
511      return false;
512    break;
513
514  case Type::TypeOf:
515    if (!IsStructurallyEquivalent(Context,
516                                  cast<TypeOfType>(T1)->getUnderlyingType(),
517                                  cast<TypeOfType>(T2)->getUnderlyingType()))
518      return false;
519    break;
520
521  case Type::Decltype:
522    if (!IsStructurallyEquivalent(Context,
523                                  cast<DecltypeType>(T1)->getUnderlyingExpr(),
524                                  cast<DecltypeType>(T2)->getUnderlyingExpr()))
525      return false;
526    break;
527
528  case Type::Record:
529  case Type::Enum:
530    if (!IsStructurallyEquivalent(Context,
531                                  cast<TagType>(T1)->getDecl(),
532                                  cast<TagType>(T2)->getDecl()))
533      return false;
534    break;
535
536  case Type::TemplateTypeParm: {
537    const TemplateTypeParmType *Parm1 = cast<TemplateTypeParmType>(T1);
538    const TemplateTypeParmType *Parm2 = cast<TemplateTypeParmType>(T2);
539    if (Parm1->getDepth() != Parm2->getDepth())
540      return false;
541    if (Parm1->getIndex() != Parm2->getIndex())
542      return false;
543    if (Parm1->isParameterPack() != Parm2->isParameterPack())
544      return false;
545
546    // Names of template type parameters are never significant.
547    break;
548  }
549
550  case Type::SubstTemplateTypeParm: {
551    const SubstTemplateTypeParmType *Subst1
552      = cast<SubstTemplateTypeParmType>(T1);
553    const SubstTemplateTypeParmType *Subst2
554      = cast<SubstTemplateTypeParmType>(T2);
555    if (!IsStructurallyEquivalent(Context,
556                                  QualType(Subst1->getReplacedParameter(), 0),
557                                  QualType(Subst2->getReplacedParameter(), 0)))
558      return false;
559    if (!IsStructurallyEquivalent(Context,
560                                  Subst1->getReplacementType(),
561                                  Subst2->getReplacementType()))
562      return false;
563    break;
564  }
565
566  case Type::TemplateSpecialization: {
567    const TemplateSpecializationType *Spec1
568      = cast<TemplateSpecializationType>(T1);
569    const TemplateSpecializationType *Spec2
570      = cast<TemplateSpecializationType>(T2);
571    if (!IsStructurallyEquivalent(Context,
572                                  Spec1->getTemplateName(),
573                                  Spec2->getTemplateName()))
574      return false;
575    if (Spec1->getNumArgs() != Spec2->getNumArgs())
576      return false;
577    for (unsigned I = 0, N = Spec1->getNumArgs(); I != N; ++I) {
578      if (!IsStructurallyEquivalent(Context,
579                                    Spec1->getArg(I), Spec2->getArg(I)))
580        return false;
581    }
582    break;
583  }
584
585  case Type::Elaborated: {
586    const ElaboratedType *Elab1 = cast<ElaboratedType>(T1);
587    const ElaboratedType *Elab2 = cast<ElaboratedType>(T2);
588    // CHECKME: what if a keyword is ETK_None or ETK_typename ?
589    if (Elab1->getKeyword() != Elab2->getKeyword())
590      return false;
591    if (!IsStructurallyEquivalent(Context,
592                                  Elab1->getQualifier(),
593                                  Elab2->getQualifier()))
594      return false;
595    if (!IsStructurallyEquivalent(Context,
596                                  Elab1->getNamedType(),
597                                  Elab2->getNamedType()))
598      return false;
599    break;
600  }
601
602  case Type::InjectedClassName: {
603    const InjectedClassNameType *Inj1 = cast<InjectedClassNameType>(T1);
604    const InjectedClassNameType *Inj2 = cast<InjectedClassNameType>(T2);
605    if (!IsStructurallyEquivalent(Context,
606                                  Inj1->getInjectedSpecializationType(),
607                                  Inj2->getInjectedSpecializationType()))
608      return false;
609    break;
610  }
611
612  case Type::DependentName: {
613    const DependentNameType *Typename1 = cast<DependentNameType>(T1);
614    const DependentNameType *Typename2 = cast<DependentNameType>(T2);
615    if (!IsStructurallyEquivalent(Context,
616                                  Typename1->getQualifier(),
617                                  Typename2->getQualifier()))
618      return false;
619    if (!IsStructurallyEquivalent(Typename1->getIdentifier(),
620                                  Typename2->getIdentifier()))
621      return false;
622    if (!IsStructurallyEquivalent(Context,
623                                  QualType(Typename1->getTemplateId(), 0),
624                                  QualType(Typename2->getTemplateId(), 0)))
625      return false;
626
627    break;
628  }
629
630  case Type::ObjCInterface: {
631    const ObjCInterfaceType *Iface1 = cast<ObjCInterfaceType>(T1);
632    const ObjCInterfaceType *Iface2 = cast<ObjCInterfaceType>(T2);
633    if (!IsStructurallyEquivalent(Context,
634                                  Iface1->getDecl(), Iface2->getDecl()))
635      return false;
636    break;
637  }
638
639  case Type::ObjCObject: {
640    const ObjCObjectType *Obj1 = cast<ObjCObjectType>(T1);
641    const ObjCObjectType *Obj2 = cast<ObjCObjectType>(T2);
642    if (!IsStructurallyEquivalent(Context,
643                                  Obj1->getBaseType(),
644                                  Obj2->getBaseType()))
645      return false;
646    if (Obj1->getNumProtocols() != Obj2->getNumProtocols())
647      return false;
648    for (unsigned I = 0, N = Obj1->getNumProtocols(); I != N; ++I) {
649      if (!IsStructurallyEquivalent(Context,
650                                    Obj1->getProtocol(I),
651                                    Obj2->getProtocol(I)))
652        return false;
653    }
654    break;
655  }
656
657  case Type::ObjCObjectPointer: {
658    const ObjCObjectPointerType *Ptr1 = cast<ObjCObjectPointerType>(T1);
659    const ObjCObjectPointerType *Ptr2 = cast<ObjCObjectPointerType>(T2);
660    if (!IsStructurallyEquivalent(Context,
661                                  Ptr1->getPointeeType(),
662                                  Ptr2->getPointeeType()))
663      return false;
664    break;
665  }
666
667  } // end switch
668
669  return true;
670}
671
672/// \brief Determine structural equivalence of two records.
673static bool IsStructurallyEquivalent(StructuralEquivalenceContext &Context,
674                                     RecordDecl *D1, RecordDecl *D2) {
675  if (D1->isUnion() != D2->isUnion()) {
676    Context.Diag2(D2->getLocation(), diag::warn_odr_tag_type_inconsistent)
677      << Context.C2.getTypeDeclType(D2);
678    Context.Diag1(D1->getLocation(), diag::note_odr_tag_kind_here)
679      << D1->getDeclName() << (unsigned)D1->getTagKind();
680    return false;
681  }
682
683  // Compare the definitions of these two records. If either or both are
684  // incomplete, we assume that they are equivalent.
685  D1 = D1->getDefinition();
686  D2 = D2->getDefinition();
687  if (!D1 || !D2)
688    return true;
689
690  if (CXXRecordDecl *D1CXX = dyn_cast<CXXRecordDecl>(D1)) {
691    if (CXXRecordDecl *D2CXX = dyn_cast<CXXRecordDecl>(D2)) {
692      if (D1CXX->getNumBases() != D2CXX->getNumBases()) {
693        Context.Diag2(D2->getLocation(), diag::warn_odr_tag_type_inconsistent)
694        << Context.C2.getTypeDeclType(D2);
695        Context.Diag2(D2->getLocation(), diag::note_odr_number_of_bases)
696        << D2CXX->getNumBases();
697        Context.Diag1(D1->getLocation(), diag::note_odr_number_of_bases)
698        << D1CXX->getNumBases();
699        return false;
700      }
701
702      // Check the base classes.
703      for (CXXRecordDecl::base_class_iterator Base1 = D1CXX->bases_begin(),
704                                           BaseEnd1 = D1CXX->bases_end(),
705                                                Base2 = D2CXX->bases_begin();
706           Base1 != BaseEnd1;
707           ++Base1, ++Base2) {
708        if (!IsStructurallyEquivalent(Context,
709                                      Base1->getType(), Base2->getType())) {
710          Context.Diag2(D2->getLocation(), diag::warn_odr_tag_type_inconsistent)
711            << Context.C2.getTypeDeclType(D2);
712          Context.Diag2(Base2->getSourceRange().getBegin(), diag::note_odr_base)
713            << Base2->getType()
714            << Base2->getSourceRange();
715          Context.Diag1(Base1->getSourceRange().getBegin(), diag::note_odr_base)
716            << Base1->getType()
717            << Base1->getSourceRange();
718          return false;
719        }
720
721        // Check virtual vs. non-virtual inheritance mismatch.
722        if (Base1->isVirtual() != Base2->isVirtual()) {
723          Context.Diag2(D2->getLocation(), diag::warn_odr_tag_type_inconsistent)
724            << Context.C2.getTypeDeclType(D2);
725          Context.Diag2(Base2->getSourceRange().getBegin(),
726                        diag::note_odr_virtual_base)
727            << Base2->isVirtual() << Base2->getSourceRange();
728          Context.Diag1(Base1->getSourceRange().getBegin(), diag::note_odr_base)
729            << Base1->isVirtual()
730            << Base1->getSourceRange();
731          return false;
732        }
733      }
734    } else if (D1CXX->getNumBases() > 0) {
735      Context.Diag2(D2->getLocation(), diag::warn_odr_tag_type_inconsistent)
736        << Context.C2.getTypeDeclType(D2);
737      const CXXBaseSpecifier *Base1 = D1CXX->bases_begin();
738      Context.Diag1(Base1->getSourceRange().getBegin(), diag::note_odr_base)
739        << Base1->getType()
740        << Base1->getSourceRange();
741      Context.Diag2(D2->getLocation(), diag::note_odr_missing_base);
742      return false;
743    }
744  }
745
746  // Check the fields for consistency.
747  CXXRecordDecl::field_iterator Field2 = D2->field_begin(),
748                             Field2End = D2->field_end();
749  for (CXXRecordDecl::field_iterator Field1 = D1->field_begin(),
750                                  Field1End = D1->field_end();
751       Field1 != Field1End;
752       ++Field1, ++Field2) {
753    if (Field2 == Field2End) {
754      Context.Diag2(D2->getLocation(), diag::warn_odr_tag_type_inconsistent)
755        << Context.C2.getTypeDeclType(D2);
756      Context.Diag1(Field1->getLocation(), diag::note_odr_field)
757        << Field1->getDeclName() << Field1->getType();
758      Context.Diag2(D2->getLocation(), diag::note_odr_missing_field);
759      return false;
760    }
761
762    if (!IsStructurallyEquivalent(Context,
763                                  Field1->getType(), Field2->getType())) {
764      Context.Diag2(D2->getLocation(), diag::warn_odr_tag_type_inconsistent)
765        << Context.C2.getTypeDeclType(D2);
766      Context.Diag2(Field2->getLocation(), diag::note_odr_field)
767        << Field2->getDeclName() << Field2->getType();
768      Context.Diag1(Field1->getLocation(), diag::note_odr_field)
769        << Field1->getDeclName() << Field1->getType();
770      return false;
771    }
772
773    if (Field1->isBitField() != Field2->isBitField()) {
774      Context.Diag2(D2->getLocation(), diag::warn_odr_tag_type_inconsistent)
775        << Context.C2.getTypeDeclType(D2);
776      if (Field1->isBitField()) {
777        llvm::APSInt Bits;
778        Field1->getBitWidth()->isIntegerConstantExpr(Bits, Context.C1);
779        Context.Diag1(Field1->getLocation(), diag::note_odr_bit_field)
780          << Field1->getDeclName() << Field1->getType()
781          << Bits.toString(10, false);
782        Context.Diag2(Field2->getLocation(), diag::note_odr_not_bit_field)
783          << Field2->getDeclName();
784      } else {
785        llvm::APSInt Bits;
786        Field2->getBitWidth()->isIntegerConstantExpr(Bits, Context.C2);
787        Context.Diag2(Field2->getLocation(), diag::note_odr_bit_field)
788          << Field2->getDeclName() << Field2->getType()
789          << Bits.toString(10, false);
790        Context.Diag1(Field1->getLocation(),
791                          diag::note_odr_not_bit_field)
792        << Field1->getDeclName();
793      }
794      return false;
795    }
796
797    if (Field1->isBitField()) {
798      // Make sure that the bit-fields are the same length.
799      llvm::APSInt Bits1, Bits2;
800      if (!Field1->getBitWidth()->isIntegerConstantExpr(Bits1, Context.C1))
801        return false;
802      if (!Field2->getBitWidth()->isIntegerConstantExpr(Bits2, Context.C2))
803        return false;
804
805      if (!IsSameValue(Bits1, Bits2)) {
806        Context.Diag2(D2->getLocation(), diag::warn_odr_tag_type_inconsistent)
807          << Context.C2.getTypeDeclType(D2);
808        Context.Diag2(Field2->getLocation(), diag::note_odr_bit_field)
809          << Field2->getDeclName() << Field2->getType()
810          << Bits2.toString(10, false);
811        Context.Diag1(Field1->getLocation(), diag::note_odr_bit_field)
812          << Field1->getDeclName() << Field1->getType()
813          << Bits1.toString(10, false);
814        return false;
815      }
816    }
817  }
818
819  if (Field2 != Field2End) {
820    Context.Diag2(D2->getLocation(), diag::warn_odr_tag_type_inconsistent)
821      << Context.C2.getTypeDeclType(D2);
822    Context.Diag2(Field2->getLocation(), diag::note_odr_field)
823      << Field2->getDeclName() << Field2->getType();
824    Context.Diag1(D1->getLocation(), diag::note_odr_missing_field);
825    return false;
826  }
827
828  return true;
829}
830
831/// \brief Determine structural equivalence of two enums.
832static bool IsStructurallyEquivalent(StructuralEquivalenceContext &Context,
833                                     EnumDecl *D1, EnumDecl *D2) {
834  EnumDecl::enumerator_iterator EC2 = D2->enumerator_begin(),
835                             EC2End = D2->enumerator_end();
836  for (EnumDecl::enumerator_iterator EC1 = D1->enumerator_begin(),
837                                  EC1End = D1->enumerator_end();
838       EC1 != EC1End; ++EC1, ++EC2) {
839    if (EC2 == EC2End) {
840      Context.Diag2(D2->getLocation(), diag::warn_odr_tag_type_inconsistent)
841        << Context.C2.getTypeDeclType(D2);
842      Context.Diag1(EC1->getLocation(), diag::note_odr_enumerator)
843        << EC1->getDeclName()
844        << EC1->getInitVal().toString(10);
845      Context.Diag2(D2->getLocation(), diag::note_odr_missing_enumerator);
846      return false;
847    }
848
849    llvm::APSInt Val1 = EC1->getInitVal();
850    llvm::APSInt Val2 = EC2->getInitVal();
851    if (!IsSameValue(Val1, Val2) ||
852        !IsStructurallyEquivalent(EC1->getIdentifier(), EC2->getIdentifier())) {
853      Context.Diag2(D2->getLocation(), diag::warn_odr_tag_type_inconsistent)
854        << Context.C2.getTypeDeclType(D2);
855      Context.Diag2(EC2->getLocation(), diag::note_odr_enumerator)
856        << EC2->getDeclName()
857        << EC2->getInitVal().toString(10);
858      Context.Diag1(EC1->getLocation(), diag::note_odr_enumerator)
859        << EC1->getDeclName()
860        << EC1->getInitVal().toString(10);
861      return false;
862    }
863  }
864
865  if (EC2 != EC2End) {
866    Context.Diag2(D2->getLocation(), diag::warn_odr_tag_type_inconsistent)
867      << Context.C2.getTypeDeclType(D2);
868    Context.Diag2(EC2->getLocation(), diag::note_odr_enumerator)
869      << EC2->getDeclName()
870      << EC2->getInitVal().toString(10);
871    Context.Diag1(D1->getLocation(), diag::note_odr_missing_enumerator);
872    return false;
873  }
874
875  return true;
876}
877
878/// \brief Determine structural equivalence of two declarations.
879static bool IsStructurallyEquivalent(StructuralEquivalenceContext &Context,
880                                     Decl *D1, Decl *D2) {
881  // FIXME: Check for known structural equivalences via a callback of some sort.
882
883  // Check whether we already know that these two declarations are not
884  // structurally equivalent.
885  if (Context.NonEquivalentDecls.count(std::make_pair(D1->getCanonicalDecl(),
886                                                      D2->getCanonicalDecl())))
887    return false;
888
889  // Determine whether we've already produced a tentative equivalence for D1.
890  Decl *&EquivToD1 = Context.TentativeEquivalences[D1->getCanonicalDecl()];
891  if (EquivToD1)
892    return EquivToD1 == D2->getCanonicalDecl();
893
894  // Produce a tentative equivalence D1 <-> D2, which will be checked later.
895  EquivToD1 = D2->getCanonicalDecl();
896  Context.DeclsToCheck.push_back(D1->getCanonicalDecl());
897  return true;
898}
899
900bool StructuralEquivalenceContext::IsStructurallyEquivalent(Decl *D1,
901                                                            Decl *D2) {
902  if (!::IsStructurallyEquivalent(*this, D1, D2))
903    return false;
904
905  return !Finish();
906}
907
908bool StructuralEquivalenceContext::IsStructurallyEquivalent(QualType T1,
909                                                            QualType T2) {
910  if (!::IsStructurallyEquivalent(*this, T1, T2))
911    return false;
912
913  return !Finish();
914}
915
916bool StructuralEquivalenceContext::Finish() {
917  while (!DeclsToCheck.empty()) {
918    // Check the next declaration.
919    Decl *D1 = DeclsToCheck.front();
920    DeclsToCheck.pop_front();
921
922    Decl *D2 = TentativeEquivalences[D1];
923    assert(D2 && "Unrecorded tentative equivalence?");
924
925    bool Equivalent = true;
926
927    // FIXME: Switch on all declaration kinds. For now, we're just going to
928    // check the obvious ones.
929    if (RecordDecl *Record1 = dyn_cast<RecordDecl>(D1)) {
930      if (RecordDecl *Record2 = dyn_cast<RecordDecl>(D2)) {
931        // Check for equivalent structure names.
932        IdentifierInfo *Name1 = Record1->getIdentifier();
933        if (!Name1 && Record1->getTypedefForAnonDecl())
934          Name1 = Record1->getTypedefForAnonDecl()->getIdentifier();
935        IdentifierInfo *Name2 = Record2->getIdentifier();
936        if (!Name2 && Record2->getTypedefForAnonDecl())
937          Name2 = Record2->getTypedefForAnonDecl()->getIdentifier();
938        if (!::IsStructurallyEquivalent(Name1, Name2) ||
939            !::IsStructurallyEquivalent(*this, Record1, Record2))
940          Equivalent = false;
941      } else {
942        // Record/non-record mismatch.
943        Equivalent = false;
944      }
945    } else if (EnumDecl *Enum1 = dyn_cast<EnumDecl>(D1)) {
946      if (EnumDecl *Enum2 = dyn_cast<EnumDecl>(D2)) {
947        // Check for equivalent enum names.
948        IdentifierInfo *Name1 = Enum1->getIdentifier();
949        if (!Name1 && Enum1->getTypedefForAnonDecl())
950          Name1 = Enum1->getTypedefForAnonDecl()->getIdentifier();
951        IdentifierInfo *Name2 = Enum2->getIdentifier();
952        if (!Name2 && Enum2->getTypedefForAnonDecl())
953          Name2 = Enum2->getTypedefForAnonDecl()->getIdentifier();
954        if (!::IsStructurallyEquivalent(Name1, Name2) ||
955            !::IsStructurallyEquivalent(*this, Enum1, Enum2))
956          Equivalent = false;
957      } else {
958        // Enum/non-enum mismatch
959        Equivalent = false;
960      }
961    } else if (TypedefDecl *Typedef1 = dyn_cast<TypedefDecl>(D1)) {
962      if (TypedefDecl *Typedef2 = dyn_cast<TypedefDecl>(D2)) {
963        if (!::IsStructurallyEquivalent(Typedef1->getIdentifier(),
964                                        Typedef2->getIdentifier()) ||
965            !::IsStructurallyEquivalent(*this,
966                                        Typedef1->getUnderlyingType(),
967                                        Typedef2->getUnderlyingType()))
968          Equivalent = false;
969      } else {
970        // Typedef/non-typedef mismatch.
971        Equivalent = false;
972      }
973    }
974
975    if (!Equivalent) {
976      // Note that these two declarations are not equivalent (and we already
977      // know about it).
978      NonEquivalentDecls.insert(std::make_pair(D1->getCanonicalDecl(),
979                                               D2->getCanonicalDecl()));
980      return true;
981    }
982    // FIXME: Check other declaration kinds!
983  }
984
985  return false;
986}
987
988//----------------------------------------------------------------------------
989// Import Types
990//----------------------------------------------------------------------------
991
992QualType ASTNodeImporter::VisitType(Type *T) {
993  Importer.FromDiag(SourceLocation(), diag::err_unsupported_ast_node)
994    << T->getTypeClassName();
995  return QualType();
996}
997
998QualType ASTNodeImporter::VisitBuiltinType(BuiltinType *T) {
999  switch (T->getKind()) {
1000  case BuiltinType::Void: return Importer.getToContext().VoidTy;
1001  case BuiltinType::Bool: return Importer.getToContext().BoolTy;
1002
1003  case BuiltinType::Char_U:
1004    // The context we're importing from has an unsigned 'char'. If we're
1005    // importing into a context with a signed 'char', translate to
1006    // 'unsigned char' instead.
1007    if (Importer.getToContext().getLangOptions().CharIsSigned)
1008      return Importer.getToContext().UnsignedCharTy;
1009
1010    return Importer.getToContext().CharTy;
1011
1012  case BuiltinType::UChar: return Importer.getToContext().UnsignedCharTy;
1013
1014  case BuiltinType::Char16:
1015    // FIXME: Make sure that the "to" context supports C++!
1016    return Importer.getToContext().Char16Ty;
1017
1018  case BuiltinType::Char32:
1019    // FIXME: Make sure that the "to" context supports C++!
1020    return Importer.getToContext().Char32Ty;
1021
1022  case BuiltinType::UShort: return Importer.getToContext().UnsignedShortTy;
1023  case BuiltinType::UInt: return Importer.getToContext().UnsignedIntTy;
1024  case BuiltinType::ULong: return Importer.getToContext().UnsignedLongTy;
1025  case BuiltinType::ULongLong:
1026    return Importer.getToContext().UnsignedLongLongTy;
1027  case BuiltinType::UInt128: return Importer.getToContext().UnsignedInt128Ty;
1028
1029  case BuiltinType::Char_S:
1030    // The context we're importing from has an unsigned 'char'. If we're
1031    // importing into a context with a signed 'char', translate to
1032    // 'unsigned char' instead.
1033    if (!Importer.getToContext().getLangOptions().CharIsSigned)
1034      return Importer.getToContext().SignedCharTy;
1035
1036    return Importer.getToContext().CharTy;
1037
1038  case BuiltinType::SChar: return Importer.getToContext().SignedCharTy;
1039  case BuiltinType::WChar:
1040    // FIXME: If not in C++, shall we translate to the C equivalent of
1041    // wchar_t?
1042    return Importer.getToContext().WCharTy;
1043
1044  case BuiltinType::Short : return Importer.getToContext().ShortTy;
1045  case BuiltinType::Int : return Importer.getToContext().IntTy;
1046  case BuiltinType::Long : return Importer.getToContext().LongTy;
1047  case BuiltinType::LongLong : return Importer.getToContext().LongLongTy;
1048  case BuiltinType::Int128 : return Importer.getToContext().Int128Ty;
1049  case BuiltinType::Float: return Importer.getToContext().FloatTy;
1050  case BuiltinType::Double: return Importer.getToContext().DoubleTy;
1051  case BuiltinType::LongDouble: return Importer.getToContext().LongDoubleTy;
1052
1053  case BuiltinType::NullPtr:
1054    // FIXME: Make sure that the "to" context supports C++0x!
1055    return Importer.getToContext().NullPtrTy;
1056
1057  case BuiltinType::Overload: return Importer.getToContext().OverloadTy;
1058  case BuiltinType::Dependent: return Importer.getToContext().DependentTy;
1059  case BuiltinType::UndeducedAuto:
1060    // FIXME: Make sure that the "to" context supports C++0x!
1061    return Importer.getToContext().UndeducedAutoTy;
1062
1063  case BuiltinType::ObjCId:
1064    // FIXME: Make sure that the "to" context supports Objective-C!
1065    return Importer.getToContext().ObjCBuiltinIdTy;
1066
1067  case BuiltinType::ObjCClass:
1068    return Importer.getToContext().ObjCBuiltinClassTy;
1069
1070  case BuiltinType::ObjCSel:
1071    return Importer.getToContext().ObjCBuiltinSelTy;
1072  }
1073
1074  return QualType();
1075}
1076
1077QualType ASTNodeImporter::VisitComplexType(ComplexType *T) {
1078  QualType ToElementType = Importer.Import(T->getElementType());
1079  if (ToElementType.isNull())
1080    return QualType();
1081
1082  return Importer.getToContext().getComplexType(ToElementType);
1083}
1084
1085QualType ASTNodeImporter::VisitPointerType(PointerType *T) {
1086  QualType ToPointeeType = Importer.Import(T->getPointeeType());
1087  if (ToPointeeType.isNull())
1088    return QualType();
1089
1090  return Importer.getToContext().getPointerType(ToPointeeType);
1091}
1092
1093QualType ASTNodeImporter::VisitBlockPointerType(BlockPointerType *T) {
1094  // FIXME: Check for blocks support in "to" context.
1095  QualType ToPointeeType = Importer.Import(T->getPointeeType());
1096  if (ToPointeeType.isNull())
1097    return QualType();
1098
1099  return Importer.getToContext().getBlockPointerType(ToPointeeType);
1100}
1101
1102QualType ASTNodeImporter::VisitLValueReferenceType(LValueReferenceType *T) {
1103  // FIXME: Check for C++ support in "to" context.
1104  QualType ToPointeeType = Importer.Import(T->getPointeeTypeAsWritten());
1105  if (ToPointeeType.isNull())
1106    return QualType();
1107
1108  return Importer.getToContext().getLValueReferenceType(ToPointeeType);
1109}
1110
1111QualType ASTNodeImporter::VisitRValueReferenceType(RValueReferenceType *T) {
1112  // FIXME: Check for C++0x support in "to" context.
1113  QualType ToPointeeType = Importer.Import(T->getPointeeTypeAsWritten());
1114  if (ToPointeeType.isNull())
1115    return QualType();
1116
1117  return Importer.getToContext().getRValueReferenceType(ToPointeeType);
1118}
1119
1120QualType ASTNodeImporter::VisitMemberPointerType(MemberPointerType *T) {
1121  // FIXME: Check for C++ support in "to" context.
1122  QualType ToPointeeType = Importer.Import(T->getPointeeType());
1123  if (ToPointeeType.isNull())
1124    return QualType();
1125
1126  QualType ClassType = Importer.Import(QualType(T->getClass(), 0));
1127  return Importer.getToContext().getMemberPointerType(ToPointeeType,
1128                                                      ClassType.getTypePtr());
1129}
1130
1131QualType ASTNodeImporter::VisitConstantArrayType(ConstantArrayType *T) {
1132  QualType ToElementType = Importer.Import(T->getElementType());
1133  if (ToElementType.isNull())
1134    return QualType();
1135
1136  return Importer.getToContext().getConstantArrayType(ToElementType,
1137                                                      T->getSize(),
1138                                                      T->getSizeModifier(),
1139                                               T->getIndexTypeCVRQualifiers());
1140}
1141
1142QualType ASTNodeImporter::VisitIncompleteArrayType(IncompleteArrayType *T) {
1143  QualType ToElementType = Importer.Import(T->getElementType());
1144  if (ToElementType.isNull())
1145    return QualType();
1146
1147  return Importer.getToContext().getIncompleteArrayType(ToElementType,
1148                                                        T->getSizeModifier(),
1149                                                T->getIndexTypeCVRQualifiers());
1150}
1151
1152QualType ASTNodeImporter::VisitVariableArrayType(VariableArrayType *T) {
1153  QualType ToElementType = Importer.Import(T->getElementType());
1154  if (ToElementType.isNull())
1155    return QualType();
1156
1157  Expr *Size = Importer.Import(T->getSizeExpr());
1158  if (!Size)
1159    return QualType();
1160
1161  SourceRange Brackets = Importer.Import(T->getBracketsRange());
1162  return Importer.getToContext().getVariableArrayType(ToElementType, Size,
1163                                                      T->getSizeModifier(),
1164                                                T->getIndexTypeCVRQualifiers(),
1165                                                      Brackets);
1166}
1167
1168QualType ASTNodeImporter::VisitVectorType(VectorType *T) {
1169  QualType ToElementType = Importer.Import(T->getElementType());
1170  if (ToElementType.isNull())
1171    return QualType();
1172
1173  return Importer.getToContext().getVectorType(ToElementType,
1174                                               T->getNumElements(),
1175                                               T->isAltiVec(),
1176                                               T->isPixel());
1177}
1178
1179QualType ASTNodeImporter::VisitExtVectorType(ExtVectorType *T) {
1180  QualType ToElementType = Importer.Import(T->getElementType());
1181  if (ToElementType.isNull())
1182    return QualType();
1183
1184  return Importer.getToContext().getExtVectorType(ToElementType,
1185                                                  T->getNumElements());
1186}
1187
1188QualType ASTNodeImporter::VisitFunctionNoProtoType(FunctionNoProtoType *T) {
1189  // FIXME: What happens if we're importing a function without a prototype
1190  // into C++? Should we make it variadic?
1191  QualType ToResultType = Importer.Import(T->getResultType());
1192  if (ToResultType.isNull())
1193    return QualType();
1194
1195  return Importer.getToContext().getFunctionNoProtoType(ToResultType,
1196                                                        T->getExtInfo());
1197}
1198
1199QualType ASTNodeImporter::VisitFunctionProtoType(FunctionProtoType *T) {
1200  QualType ToResultType = Importer.Import(T->getResultType());
1201  if (ToResultType.isNull())
1202    return QualType();
1203
1204  // Import argument types
1205  llvm::SmallVector<QualType, 4> ArgTypes;
1206  for (FunctionProtoType::arg_type_iterator A = T->arg_type_begin(),
1207                                         AEnd = T->arg_type_end();
1208       A != AEnd; ++A) {
1209    QualType ArgType = Importer.Import(*A);
1210    if (ArgType.isNull())
1211      return QualType();
1212    ArgTypes.push_back(ArgType);
1213  }
1214
1215  // Import exception types
1216  llvm::SmallVector<QualType, 4> ExceptionTypes;
1217  for (FunctionProtoType::exception_iterator E = T->exception_begin(),
1218                                          EEnd = T->exception_end();
1219       E != EEnd; ++E) {
1220    QualType ExceptionType = Importer.Import(*E);
1221    if (ExceptionType.isNull())
1222      return QualType();
1223    ExceptionTypes.push_back(ExceptionType);
1224  }
1225
1226  return Importer.getToContext().getFunctionType(ToResultType, ArgTypes.data(),
1227                                                 ArgTypes.size(),
1228                                                 T->isVariadic(),
1229                                                 T->getTypeQuals(),
1230                                                 T->hasExceptionSpec(),
1231                                                 T->hasAnyExceptionSpec(),
1232                                                 ExceptionTypes.size(),
1233                                                 ExceptionTypes.data(),
1234                                                 T->getExtInfo());
1235}
1236
1237QualType ASTNodeImporter::VisitTypedefType(TypedefType *T) {
1238  TypedefDecl *ToDecl
1239                 = dyn_cast_or_null<TypedefDecl>(Importer.Import(T->getDecl()));
1240  if (!ToDecl)
1241    return QualType();
1242
1243  return Importer.getToContext().getTypeDeclType(ToDecl);
1244}
1245
1246QualType ASTNodeImporter::VisitTypeOfExprType(TypeOfExprType *T) {
1247  Expr *ToExpr = Importer.Import(T->getUnderlyingExpr());
1248  if (!ToExpr)
1249    return QualType();
1250
1251  return Importer.getToContext().getTypeOfExprType(ToExpr);
1252}
1253
1254QualType ASTNodeImporter::VisitTypeOfType(TypeOfType *T) {
1255  QualType ToUnderlyingType = Importer.Import(T->getUnderlyingType());
1256  if (ToUnderlyingType.isNull())
1257    return QualType();
1258
1259  return Importer.getToContext().getTypeOfType(ToUnderlyingType);
1260}
1261
1262QualType ASTNodeImporter::VisitDecltypeType(DecltypeType *T) {
1263  Expr *ToExpr = Importer.Import(T->getUnderlyingExpr());
1264  if (!ToExpr)
1265    return QualType();
1266
1267  return Importer.getToContext().getDecltypeType(ToExpr);
1268}
1269
1270QualType ASTNodeImporter::VisitRecordType(RecordType *T) {
1271  RecordDecl *ToDecl
1272    = dyn_cast_or_null<RecordDecl>(Importer.Import(T->getDecl()));
1273  if (!ToDecl)
1274    return QualType();
1275
1276  return Importer.getToContext().getTagDeclType(ToDecl);
1277}
1278
1279QualType ASTNodeImporter::VisitEnumType(EnumType *T) {
1280  EnumDecl *ToDecl
1281    = dyn_cast_or_null<EnumDecl>(Importer.Import(T->getDecl()));
1282  if (!ToDecl)
1283    return QualType();
1284
1285  return Importer.getToContext().getTagDeclType(ToDecl);
1286}
1287
1288QualType ASTNodeImporter::VisitElaboratedType(ElaboratedType *T) {
1289  NestedNameSpecifier *ToQualifier = 0;
1290  // Note: the qualifier in an ElaboratedType is optional.
1291  if (T->getQualifier()) {
1292    ToQualifier = Importer.Import(T->getQualifier());
1293    if (!ToQualifier)
1294      return QualType();
1295  }
1296
1297  QualType ToNamedType = Importer.Import(T->getNamedType());
1298  if (ToNamedType.isNull())
1299    return QualType();
1300
1301  return Importer.getToContext().getElaboratedType(T->getKeyword(),
1302                                                   ToQualifier, ToNamedType);
1303}
1304
1305QualType ASTNodeImporter::VisitObjCInterfaceType(ObjCInterfaceType *T) {
1306  ObjCInterfaceDecl *Class
1307    = dyn_cast_or_null<ObjCInterfaceDecl>(Importer.Import(T->getDecl()));
1308  if (!Class)
1309    return QualType();
1310
1311  return Importer.getToContext().getObjCInterfaceType(Class);
1312}
1313
1314QualType ASTNodeImporter::VisitObjCObjectType(ObjCObjectType *T) {
1315  QualType ToBaseType = Importer.Import(T->getBaseType());
1316  if (ToBaseType.isNull())
1317    return QualType();
1318
1319  llvm::SmallVector<ObjCProtocolDecl *, 4> Protocols;
1320  for (ObjCObjectType::qual_iterator P = T->qual_begin(),
1321                                     PEnd = T->qual_end();
1322       P != PEnd; ++P) {
1323    ObjCProtocolDecl *Protocol
1324      = dyn_cast_or_null<ObjCProtocolDecl>(Importer.Import(*P));
1325    if (!Protocol)
1326      return QualType();
1327    Protocols.push_back(Protocol);
1328  }
1329
1330  return Importer.getToContext().getObjCObjectType(ToBaseType,
1331                                                   Protocols.data(),
1332                                                   Protocols.size());
1333}
1334
1335QualType ASTNodeImporter::VisitObjCObjectPointerType(ObjCObjectPointerType *T) {
1336  QualType ToPointeeType = Importer.Import(T->getPointeeType());
1337  if (ToPointeeType.isNull())
1338    return QualType();
1339
1340  return Importer.getToContext().getObjCObjectPointerType(ToPointeeType);
1341}
1342
1343//----------------------------------------------------------------------------
1344// Import Declarations
1345//----------------------------------------------------------------------------
1346bool ASTNodeImporter::ImportDeclParts(NamedDecl *D, DeclContext *&DC,
1347                                      DeclContext *&LexicalDC,
1348                                      DeclarationName &Name,
1349                                      SourceLocation &Loc) {
1350  // Import the context of this declaration.
1351  DC = Importer.ImportContext(D->getDeclContext());
1352  if (!DC)
1353    return true;
1354
1355  LexicalDC = DC;
1356  if (D->getDeclContext() != D->getLexicalDeclContext()) {
1357    LexicalDC = Importer.ImportContext(D->getLexicalDeclContext());
1358    if (!LexicalDC)
1359      return true;
1360  }
1361
1362  // Import the name of this declaration.
1363  Name = Importer.Import(D->getDeclName());
1364  if (D->getDeclName() && !Name)
1365    return true;
1366
1367  // Import the location of this declaration.
1368  Loc = Importer.Import(D->getLocation());
1369  return false;
1370}
1371
1372void ASTNodeImporter::ImportDeclContext(DeclContext *FromDC) {
1373  for (DeclContext::decl_iterator From = FromDC->decls_begin(),
1374                               FromEnd = FromDC->decls_end();
1375       From != FromEnd;
1376       ++From)
1377    Importer.Import(*From);
1378}
1379
1380bool ASTNodeImporter::IsStructuralMatch(RecordDecl *FromRecord,
1381                                        RecordDecl *ToRecord) {
1382  StructuralEquivalenceContext Ctx(Importer.getFromContext(),
1383                                   Importer.getToContext(),
1384                                   Importer.getDiags(),
1385                                   Importer.getNonEquivalentDecls());
1386  return Ctx.IsStructurallyEquivalent(FromRecord, ToRecord);
1387}
1388
1389bool ASTNodeImporter::IsStructuralMatch(EnumDecl *FromEnum, EnumDecl *ToEnum) {
1390  StructuralEquivalenceContext Ctx(Importer.getFromContext(),
1391                                   Importer.getToContext(),
1392                                   Importer.getDiags(),
1393                                   Importer.getNonEquivalentDecls());
1394  return Ctx.IsStructurallyEquivalent(FromEnum, ToEnum);
1395}
1396
1397Decl *ASTNodeImporter::VisitDecl(Decl *D) {
1398  Importer.FromDiag(D->getLocation(), diag::err_unsupported_ast_node)
1399    << D->getDeclKindName();
1400  return 0;
1401}
1402
1403Decl *ASTNodeImporter::VisitNamespaceDecl(NamespaceDecl *D) {
1404  // Import the major distinguishing characteristics of this namespace.
1405  DeclContext *DC, *LexicalDC;
1406  DeclarationName Name;
1407  SourceLocation Loc;
1408  if (ImportDeclParts(D, DC, LexicalDC, Name, Loc))
1409    return 0;
1410
1411  NamespaceDecl *MergeWithNamespace = 0;
1412  if (!Name) {
1413    // This is an anonymous namespace. Adopt an existing anonymous
1414    // namespace if we can.
1415    // FIXME: Not testable.
1416    if (TranslationUnitDecl *TU = dyn_cast<TranslationUnitDecl>(DC))
1417      MergeWithNamespace = TU->getAnonymousNamespace();
1418    else
1419      MergeWithNamespace = cast<NamespaceDecl>(DC)->getAnonymousNamespace();
1420  } else {
1421    llvm::SmallVector<NamedDecl *, 4> ConflictingDecls;
1422    for (DeclContext::lookup_result Lookup = DC->lookup(Name);
1423         Lookup.first != Lookup.second;
1424         ++Lookup.first) {
1425      if (!(*Lookup.first)->isInIdentifierNamespace(Decl::IDNS_Namespace))
1426        continue;
1427
1428      if (NamespaceDecl *FoundNS = dyn_cast<NamespaceDecl>(*Lookup.first)) {
1429        MergeWithNamespace = FoundNS;
1430        ConflictingDecls.clear();
1431        break;
1432      }
1433
1434      ConflictingDecls.push_back(*Lookup.first);
1435    }
1436
1437    if (!ConflictingDecls.empty()) {
1438      Name = Importer.HandleNameConflict(Name, DC, Decl::IDNS_Namespace,
1439                                         ConflictingDecls.data(),
1440                                         ConflictingDecls.size());
1441    }
1442  }
1443
1444  // Create the "to" namespace, if needed.
1445  NamespaceDecl *ToNamespace = MergeWithNamespace;
1446  if (!ToNamespace) {
1447    ToNamespace = NamespaceDecl::Create(Importer.getToContext(), DC, Loc,
1448                                        Name.getAsIdentifierInfo());
1449    ToNamespace->setLexicalDeclContext(LexicalDC);
1450    LexicalDC->addDecl(ToNamespace);
1451
1452    // If this is an anonymous namespace, register it as the anonymous
1453    // namespace within its context.
1454    if (!Name) {
1455      if (TranslationUnitDecl *TU = dyn_cast<TranslationUnitDecl>(DC))
1456        TU->setAnonymousNamespace(ToNamespace);
1457      else
1458        cast<NamespaceDecl>(DC)->setAnonymousNamespace(ToNamespace);
1459    }
1460  }
1461  Importer.Imported(D, ToNamespace);
1462
1463  ImportDeclContext(D);
1464
1465  return ToNamespace;
1466}
1467
1468Decl *ASTNodeImporter::VisitTypedefDecl(TypedefDecl *D) {
1469  // Import the major distinguishing characteristics of this typedef.
1470  DeclContext *DC, *LexicalDC;
1471  DeclarationName Name;
1472  SourceLocation Loc;
1473  if (ImportDeclParts(D, DC, LexicalDC, Name, Loc))
1474    return 0;
1475
1476  // If this typedef is not in block scope, determine whether we've
1477  // seen a typedef with the same name (that we can merge with) or any
1478  // other entity by that name (which name lookup could conflict with).
1479  if (!DC->isFunctionOrMethod()) {
1480    llvm::SmallVector<NamedDecl *, 4> ConflictingDecls;
1481    unsigned IDNS = Decl::IDNS_Ordinary;
1482    for (DeclContext::lookup_result Lookup = DC->lookup(Name);
1483         Lookup.first != Lookup.second;
1484         ++Lookup.first) {
1485      if (!(*Lookup.first)->isInIdentifierNamespace(IDNS))
1486        continue;
1487      if (TypedefDecl *FoundTypedef = dyn_cast<TypedefDecl>(*Lookup.first)) {
1488        if (Importer.IsStructurallyEquivalent(D->getUnderlyingType(),
1489                                            FoundTypedef->getUnderlyingType()))
1490          return Importer.Imported(D, FoundTypedef);
1491      }
1492
1493      ConflictingDecls.push_back(*Lookup.first);
1494    }
1495
1496    if (!ConflictingDecls.empty()) {
1497      Name = Importer.HandleNameConflict(Name, DC, IDNS,
1498                                         ConflictingDecls.data(),
1499                                         ConflictingDecls.size());
1500      if (!Name)
1501        return 0;
1502    }
1503  }
1504
1505  // Import the underlying type of this typedef;
1506  QualType T = Importer.Import(D->getUnderlyingType());
1507  if (T.isNull())
1508    return 0;
1509
1510  // Create the new typedef node.
1511  TypeSourceInfo *TInfo = Importer.Import(D->getTypeSourceInfo());
1512  TypedefDecl *ToTypedef = TypedefDecl::Create(Importer.getToContext(), DC,
1513                                               Loc, Name.getAsIdentifierInfo(),
1514                                               TInfo);
1515  ToTypedef->setAccess(D->getAccess());
1516  ToTypedef->setLexicalDeclContext(LexicalDC);
1517  Importer.Imported(D, ToTypedef);
1518  LexicalDC->addDecl(ToTypedef);
1519
1520  return ToTypedef;
1521}
1522
1523Decl *ASTNodeImporter::VisitEnumDecl(EnumDecl *D) {
1524  // Import the major distinguishing characteristics of this enum.
1525  DeclContext *DC, *LexicalDC;
1526  DeclarationName Name;
1527  SourceLocation Loc;
1528  if (ImportDeclParts(D, DC, LexicalDC, Name, Loc))
1529    return 0;
1530
1531  // Figure out what enum name we're looking for.
1532  unsigned IDNS = Decl::IDNS_Tag;
1533  DeclarationName SearchName = Name;
1534  if (!SearchName && D->getTypedefForAnonDecl()) {
1535    SearchName = Importer.Import(D->getTypedefForAnonDecl()->getDeclName());
1536    IDNS = Decl::IDNS_Ordinary;
1537  } else if (Importer.getToContext().getLangOptions().CPlusPlus)
1538    IDNS |= Decl::IDNS_Ordinary;
1539
1540  // We may already have an enum of the same name; try to find and match it.
1541  if (!DC->isFunctionOrMethod() && SearchName) {
1542    llvm::SmallVector<NamedDecl *, 4> ConflictingDecls;
1543    for (DeclContext::lookup_result Lookup = DC->lookup(Name);
1544         Lookup.first != Lookup.second;
1545         ++Lookup.first) {
1546      if (!(*Lookup.first)->isInIdentifierNamespace(IDNS))
1547        continue;
1548
1549      Decl *Found = *Lookup.first;
1550      if (TypedefDecl *Typedef = dyn_cast<TypedefDecl>(Found)) {
1551        if (const TagType *Tag = Typedef->getUnderlyingType()->getAs<TagType>())
1552          Found = Tag->getDecl();
1553      }
1554
1555      if (EnumDecl *FoundEnum = dyn_cast<EnumDecl>(Found)) {
1556        if (IsStructuralMatch(D, FoundEnum))
1557          return Importer.Imported(D, FoundEnum);
1558      }
1559
1560      ConflictingDecls.push_back(*Lookup.first);
1561    }
1562
1563    if (!ConflictingDecls.empty()) {
1564      Name = Importer.HandleNameConflict(Name, DC, IDNS,
1565                                         ConflictingDecls.data(),
1566                                         ConflictingDecls.size());
1567    }
1568  }
1569
1570  // Create the enum declaration.
1571  EnumDecl *D2 = EnumDecl::Create(Importer.getToContext(), DC, Loc,
1572                                      Name.getAsIdentifierInfo(),
1573                                      Importer.Import(D->getTagKeywordLoc()),
1574                                      0);
1575  // Import the qualifier, if any.
1576  if (D->getQualifier()) {
1577    NestedNameSpecifier *NNS = Importer.Import(D->getQualifier());
1578    SourceRange NNSRange = Importer.Import(D->getQualifierRange());
1579    D2->setQualifierInfo(NNS, NNSRange);
1580  }
1581  D2->setAccess(D->getAccess());
1582  D2->setLexicalDeclContext(LexicalDC);
1583  Importer.Imported(D, D2);
1584  LexicalDC->addDecl(D2);
1585
1586  // Import the integer type.
1587  QualType ToIntegerType = Importer.Import(D->getIntegerType());
1588  if (ToIntegerType.isNull())
1589    return 0;
1590  D2->setIntegerType(ToIntegerType);
1591
1592  // Import the definition
1593  if (D->isDefinition()) {
1594    QualType T = Importer.Import(Importer.getFromContext().getTypeDeclType(D));
1595    if (T.isNull())
1596      return 0;
1597
1598    QualType ToPromotionType = Importer.Import(D->getPromotionType());
1599    if (ToPromotionType.isNull())
1600      return 0;
1601
1602    D2->startDefinition();
1603    ImportDeclContext(D);
1604
1605    // FIXME: we might need to merge the number of positive or negative bits
1606    // if the enumerator lists don't match.
1607    D2->completeDefinition(T, ToPromotionType,
1608                           D->getNumPositiveBits(),
1609                           D->getNumNegativeBits());
1610  }
1611
1612  return D2;
1613}
1614
1615Decl *ASTNodeImporter::VisitRecordDecl(RecordDecl *D) {
1616  // If this record has a definition in the translation unit we're coming from,
1617  // but this particular declaration is not that definition, import the
1618  // definition and map to that.
1619  TagDecl *Definition = D->getDefinition();
1620  if (Definition && Definition != D) {
1621    Decl *ImportedDef = Importer.Import(Definition);
1622    if (!ImportedDef)
1623      return 0;
1624
1625    return Importer.Imported(D, ImportedDef);
1626  }
1627
1628  // Import the major distinguishing characteristics of this record.
1629  DeclContext *DC, *LexicalDC;
1630  DeclarationName Name;
1631  SourceLocation Loc;
1632  if (ImportDeclParts(D, DC, LexicalDC, Name, Loc))
1633    return 0;
1634
1635  // Figure out what structure name we're looking for.
1636  unsigned IDNS = Decl::IDNS_Tag;
1637  DeclarationName SearchName = Name;
1638  if (!SearchName && D->getTypedefForAnonDecl()) {
1639    SearchName = Importer.Import(D->getTypedefForAnonDecl()->getDeclName());
1640    IDNS = Decl::IDNS_Ordinary;
1641  } else if (Importer.getToContext().getLangOptions().CPlusPlus)
1642    IDNS |= Decl::IDNS_Ordinary;
1643
1644  // We may already have a record of the same name; try to find and match it.
1645  RecordDecl *AdoptDecl = 0;
1646  if (!DC->isFunctionOrMethod() && SearchName) {
1647    llvm::SmallVector<NamedDecl *, 4> ConflictingDecls;
1648    for (DeclContext::lookup_result Lookup = DC->lookup(Name);
1649         Lookup.first != Lookup.second;
1650         ++Lookup.first) {
1651      if (!(*Lookup.first)->isInIdentifierNamespace(IDNS))
1652        continue;
1653
1654      Decl *Found = *Lookup.first;
1655      if (TypedefDecl *Typedef = dyn_cast<TypedefDecl>(Found)) {
1656        if (const TagType *Tag = Typedef->getUnderlyingType()->getAs<TagType>())
1657          Found = Tag->getDecl();
1658      }
1659
1660      if (RecordDecl *FoundRecord = dyn_cast<RecordDecl>(Found)) {
1661        if (RecordDecl *FoundDef = FoundRecord->getDefinition()) {
1662          if (!D->isDefinition() || IsStructuralMatch(D, FoundDef)) {
1663            // The record types structurally match, or the "from" translation
1664            // unit only had a forward declaration anyway; call it the same
1665            // function.
1666            // FIXME: For C++, we should also merge methods here.
1667            return Importer.Imported(D, FoundDef);
1668          }
1669        } else {
1670          // We have a forward declaration of this type, so adopt that forward
1671          // declaration rather than building a new one.
1672          AdoptDecl = FoundRecord;
1673          continue;
1674        }
1675      }
1676
1677      ConflictingDecls.push_back(*Lookup.first);
1678    }
1679
1680    if (!ConflictingDecls.empty()) {
1681      Name = Importer.HandleNameConflict(Name, DC, IDNS,
1682                                         ConflictingDecls.data(),
1683                                         ConflictingDecls.size());
1684    }
1685  }
1686
1687  // Create the record declaration.
1688  RecordDecl *D2 = AdoptDecl;
1689  if (!D2) {
1690    if (isa<CXXRecordDecl>(D)) {
1691      CXXRecordDecl *D2CXX = CXXRecordDecl::Create(Importer.getToContext(),
1692                                                   D->getTagKind(),
1693                                                   DC, Loc,
1694                                                   Name.getAsIdentifierInfo(),
1695                                        Importer.Import(D->getTagKeywordLoc()));
1696      D2 = D2CXX;
1697      D2->setAccess(D->getAccess());
1698    } else {
1699      D2 = RecordDecl::Create(Importer.getToContext(), D->getTagKind(),
1700                                    DC, Loc,
1701                                    Name.getAsIdentifierInfo(),
1702                                    Importer.Import(D->getTagKeywordLoc()));
1703    }
1704    // Import the qualifier, if any.
1705    if (D->getQualifier()) {
1706      NestedNameSpecifier *NNS = Importer.Import(D->getQualifier());
1707      SourceRange NNSRange = Importer.Import(D->getQualifierRange());
1708      D2->setQualifierInfo(NNS, NNSRange);
1709    }
1710    D2->setLexicalDeclContext(LexicalDC);
1711    LexicalDC->addDecl(D2);
1712  }
1713
1714  Importer.Imported(D, D2);
1715
1716  if (D->isDefinition()) {
1717    D2->startDefinition();
1718
1719    // Add base classes.
1720    if (CXXRecordDecl *D2CXX = dyn_cast<CXXRecordDecl>(D2)) {
1721      CXXRecordDecl *D1CXX = cast<CXXRecordDecl>(D);
1722
1723      llvm::SmallVector<CXXBaseSpecifier *, 4> Bases;
1724      for (CXXRecordDecl::base_class_iterator
1725                Base1 = D1CXX->bases_begin(),
1726             FromBaseEnd = D1CXX->bases_end();
1727           Base1 != FromBaseEnd;
1728           ++Base1) {
1729        QualType T = Importer.Import(Base1->getType());
1730        if (T.isNull())
1731          return 0;
1732
1733        Bases.push_back(
1734          new (Importer.getToContext())
1735                CXXBaseSpecifier(Importer.Import(Base1->getSourceRange()),
1736                                 Base1->isVirtual(),
1737                                 Base1->isBaseOfClass(),
1738                                 Base1->getAccessSpecifierAsWritten(),
1739                                 T));
1740      }
1741      if (!Bases.empty())
1742        D2CXX->setBases(Bases.data(), Bases.size());
1743    }
1744
1745    ImportDeclContext(D);
1746    D2->completeDefinition();
1747  }
1748
1749  return D2;
1750}
1751
1752Decl *ASTNodeImporter::VisitEnumConstantDecl(EnumConstantDecl *D) {
1753  // Import the major distinguishing characteristics of this enumerator.
1754  DeclContext *DC, *LexicalDC;
1755  DeclarationName Name;
1756  SourceLocation Loc;
1757  if (ImportDeclParts(D, DC, LexicalDC, Name, Loc))
1758    return 0;
1759
1760  QualType T = Importer.Import(D->getType());
1761  if (T.isNull())
1762    return 0;
1763
1764  // Determine whether there are any other declarations with the same name and
1765  // in the same context.
1766  if (!LexicalDC->isFunctionOrMethod()) {
1767    llvm::SmallVector<NamedDecl *, 4> ConflictingDecls;
1768    unsigned IDNS = Decl::IDNS_Ordinary;
1769    for (DeclContext::lookup_result Lookup = DC->lookup(Name);
1770         Lookup.first != Lookup.second;
1771         ++Lookup.first) {
1772      if (!(*Lookup.first)->isInIdentifierNamespace(IDNS))
1773        continue;
1774
1775      ConflictingDecls.push_back(*Lookup.first);
1776    }
1777
1778    if (!ConflictingDecls.empty()) {
1779      Name = Importer.HandleNameConflict(Name, DC, IDNS,
1780                                         ConflictingDecls.data(),
1781                                         ConflictingDecls.size());
1782      if (!Name)
1783        return 0;
1784    }
1785  }
1786
1787  Expr *Init = Importer.Import(D->getInitExpr());
1788  if (D->getInitExpr() && !Init)
1789    return 0;
1790
1791  EnumConstantDecl *ToEnumerator
1792    = EnumConstantDecl::Create(Importer.getToContext(), cast<EnumDecl>(DC), Loc,
1793                               Name.getAsIdentifierInfo(), T,
1794                               Init, D->getInitVal());
1795  ToEnumerator->setAccess(D->getAccess());
1796  ToEnumerator->setLexicalDeclContext(LexicalDC);
1797  Importer.Imported(D, ToEnumerator);
1798  LexicalDC->addDecl(ToEnumerator);
1799  return ToEnumerator;
1800}
1801
1802Decl *ASTNodeImporter::VisitFunctionDecl(FunctionDecl *D) {
1803  // Import the major distinguishing characteristics of this function.
1804  DeclContext *DC, *LexicalDC;
1805  DeclarationName Name;
1806  SourceLocation Loc;
1807  if (ImportDeclParts(D, DC, LexicalDC, Name, Loc))
1808    return 0;
1809
1810  // Try to find a function in our own ("to") context with the same name, same
1811  // type, and in the same context as the function we're importing.
1812  if (!LexicalDC->isFunctionOrMethod()) {
1813    llvm::SmallVector<NamedDecl *, 4> ConflictingDecls;
1814    unsigned IDNS = Decl::IDNS_Ordinary;
1815    for (DeclContext::lookup_result Lookup = DC->lookup(Name);
1816         Lookup.first != Lookup.second;
1817         ++Lookup.first) {
1818      if (!(*Lookup.first)->isInIdentifierNamespace(IDNS))
1819        continue;
1820
1821      if (FunctionDecl *FoundFunction = dyn_cast<FunctionDecl>(*Lookup.first)) {
1822        if (isExternalLinkage(FoundFunction->getLinkage()) &&
1823            isExternalLinkage(D->getLinkage())) {
1824          if (Importer.IsStructurallyEquivalent(D->getType(),
1825                                                FoundFunction->getType())) {
1826            // FIXME: Actually try to merge the body and other attributes.
1827            return Importer.Imported(D, FoundFunction);
1828          }
1829
1830          // FIXME: Check for overloading more carefully, e.g., by boosting
1831          // Sema::IsOverload out to the AST library.
1832
1833          // Function overloading is okay in C++.
1834          if (Importer.getToContext().getLangOptions().CPlusPlus)
1835            continue;
1836
1837          // Complain about inconsistent function types.
1838          Importer.ToDiag(Loc, diag::err_odr_function_type_inconsistent)
1839            << Name << D->getType() << FoundFunction->getType();
1840          Importer.ToDiag(FoundFunction->getLocation(),
1841                          diag::note_odr_value_here)
1842            << FoundFunction->getType();
1843        }
1844      }
1845
1846      ConflictingDecls.push_back(*Lookup.first);
1847    }
1848
1849    if (!ConflictingDecls.empty()) {
1850      Name = Importer.HandleNameConflict(Name, DC, IDNS,
1851                                         ConflictingDecls.data(),
1852                                         ConflictingDecls.size());
1853      if (!Name)
1854        return 0;
1855    }
1856  }
1857
1858  // Import the type.
1859  QualType T = Importer.Import(D->getType());
1860  if (T.isNull())
1861    return 0;
1862
1863  // Import the function parameters.
1864  llvm::SmallVector<ParmVarDecl *, 8> Parameters;
1865  for (FunctionDecl::param_iterator P = D->param_begin(), PEnd = D->param_end();
1866       P != PEnd; ++P) {
1867    ParmVarDecl *ToP = cast_or_null<ParmVarDecl>(Importer.Import(*P));
1868    if (!ToP)
1869      return 0;
1870
1871    Parameters.push_back(ToP);
1872  }
1873
1874  // Create the imported function.
1875  TypeSourceInfo *TInfo = Importer.Import(D->getTypeSourceInfo());
1876  FunctionDecl *ToFunction = 0;
1877  if (CXXConstructorDecl *FromConstructor = dyn_cast<CXXConstructorDecl>(D)) {
1878    ToFunction = CXXConstructorDecl::Create(Importer.getToContext(),
1879                                            cast<CXXRecordDecl>(DC),
1880                                            Loc, Name, T, TInfo,
1881                                            FromConstructor->isExplicit(),
1882                                            D->isInlineSpecified(),
1883                                            D->isImplicit());
1884  } else if (isa<CXXDestructorDecl>(D)) {
1885    ToFunction = CXXDestructorDecl::Create(Importer.getToContext(),
1886                                           cast<CXXRecordDecl>(DC),
1887                                           Loc, Name, T,
1888                                           D->isInlineSpecified(),
1889                                           D->isImplicit());
1890  } else if (CXXConversionDecl *FromConversion
1891                                           = dyn_cast<CXXConversionDecl>(D)) {
1892    ToFunction = CXXConversionDecl::Create(Importer.getToContext(),
1893                                           cast<CXXRecordDecl>(DC),
1894                                           Loc, Name, T, TInfo,
1895                                           D->isInlineSpecified(),
1896                                           FromConversion->isExplicit());
1897  } else {
1898    ToFunction = FunctionDecl::Create(Importer.getToContext(), DC, Loc,
1899                                      Name, T, TInfo, D->getStorageClass(),
1900                                      D->getStorageClassAsWritten(),
1901                                      D->isInlineSpecified(),
1902                                      D->hasWrittenPrototype());
1903  }
1904
1905  // Import the qualifier, if any.
1906  if (D->getQualifier()) {
1907    NestedNameSpecifier *NNS = Importer.Import(D->getQualifier());
1908    SourceRange NNSRange = Importer.Import(D->getQualifierRange());
1909    ToFunction->setQualifierInfo(NNS, NNSRange);
1910  }
1911  ToFunction->setAccess(D->getAccess());
1912  ToFunction->setLexicalDeclContext(LexicalDC);
1913  Importer.Imported(D, ToFunction);
1914  LexicalDC->addDecl(ToFunction);
1915
1916  // Set the parameters.
1917  for (unsigned I = 0, N = Parameters.size(); I != N; ++I) {
1918    Parameters[I]->setOwningFunction(ToFunction);
1919    ToFunction->addDecl(Parameters[I]);
1920  }
1921  ToFunction->setParams(Parameters.data(), Parameters.size());
1922
1923  // FIXME: Other bits to merge?
1924
1925  return ToFunction;
1926}
1927
1928Decl *ASTNodeImporter::VisitCXXMethodDecl(CXXMethodDecl *D) {
1929  return VisitFunctionDecl(D);
1930}
1931
1932Decl *ASTNodeImporter::VisitCXXConstructorDecl(CXXConstructorDecl *D) {
1933  return VisitCXXMethodDecl(D);
1934}
1935
1936Decl *ASTNodeImporter::VisitCXXDestructorDecl(CXXDestructorDecl *D) {
1937  return VisitCXXMethodDecl(D);
1938}
1939
1940Decl *ASTNodeImporter::VisitCXXConversionDecl(CXXConversionDecl *D) {
1941  return VisitCXXMethodDecl(D);
1942}
1943
1944Decl *ASTNodeImporter::VisitFieldDecl(FieldDecl *D) {
1945  // Import the major distinguishing characteristics of a variable.
1946  DeclContext *DC, *LexicalDC;
1947  DeclarationName Name;
1948  SourceLocation Loc;
1949  if (ImportDeclParts(D, DC, LexicalDC, Name, Loc))
1950    return 0;
1951
1952  // Import the type.
1953  QualType T = Importer.Import(D->getType());
1954  if (T.isNull())
1955    return 0;
1956
1957  TypeSourceInfo *TInfo = Importer.Import(D->getTypeSourceInfo());
1958  Expr *BitWidth = Importer.Import(D->getBitWidth());
1959  if (!BitWidth && D->getBitWidth())
1960    return 0;
1961
1962  FieldDecl *ToField = FieldDecl::Create(Importer.getToContext(), DC,
1963                                         Loc, Name.getAsIdentifierInfo(),
1964                                         T, TInfo, BitWidth, D->isMutable());
1965  ToField->setAccess(D->getAccess());
1966  ToField->setLexicalDeclContext(LexicalDC);
1967  Importer.Imported(D, ToField);
1968  LexicalDC->addDecl(ToField);
1969  return ToField;
1970}
1971
1972Decl *ASTNodeImporter::VisitObjCIvarDecl(ObjCIvarDecl *D) {
1973  // Import the major distinguishing characteristics of an ivar.
1974  DeclContext *DC, *LexicalDC;
1975  DeclarationName Name;
1976  SourceLocation Loc;
1977  if (ImportDeclParts(D, DC, LexicalDC, Name, Loc))
1978    return 0;
1979
1980  // Determine whether we've already imported this ivar
1981  for (DeclContext::lookup_result Lookup = DC->lookup(Name);
1982       Lookup.first != Lookup.second;
1983       ++Lookup.first) {
1984    if (ObjCIvarDecl *FoundIvar = dyn_cast<ObjCIvarDecl>(*Lookup.first)) {
1985      if (Importer.IsStructurallyEquivalent(D->getType(),
1986                                            FoundIvar->getType())) {
1987        Importer.Imported(D, FoundIvar);
1988        return FoundIvar;
1989      }
1990
1991      Importer.ToDiag(Loc, diag::err_odr_ivar_type_inconsistent)
1992        << Name << D->getType() << FoundIvar->getType();
1993      Importer.ToDiag(FoundIvar->getLocation(), diag::note_odr_value_here)
1994        << FoundIvar->getType();
1995      return 0;
1996    }
1997  }
1998
1999  // Import the type.
2000  QualType T = Importer.Import(D->getType());
2001  if (T.isNull())
2002    return 0;
2003
2004  TypeSourceInfo *TInfo = Importer.Import(D->getTypeSourceInfo());
2005  Expr *BitWidth = Importer.Import(D->getBitWidth());
2006  if (!BitWidth && D->getBitWidth())
2007    return 0;
2008
2009  ObjCIvarDecl *ToIvar = ObjCIvarDecl::Create(Importer.getToContext(),
2010                                              cast<ObjCContainerDecl>(DC),
2011                                              Loc, Name.getAsIdentifierInfo(),
2012                                              T, TInfo, D->getAccessControl(),
2013                                              BitWidth);
2014  ToIvar->setLexicalDeclContext(LexicalDC);
2015  Importer.Imported(D, ToIvar);
2016  LexicalDC->addDecl(ToIvar);
2017  return ToIvar;
2018
2019}
2020
2021Decl *ASTNodeImporter::VisitVarDecl(VarDecl *D) {
2022  // Import the major distinguishing characteristics of a variable.
2023  DeclContext *DC, *LexicalDC;
2024  DeclarationName Name;
2025  SourceLocation Loc;
2026  if (ImportDeclParts(D, DC, LexicalDC, Name, Loc))
2027    return 0;
2028
2029  // Try to find a variable in our own ("to") context with the same name and
2030  // in the same context as the variable we're importing.
2031  if (D->isFileVarDecl()) {
2032    VarDecl *MergeWithVar = 0;
2033    llvm::SmallVector<NamedDecl *, 4> ConflictingDecls;
2034    unsigned IDNS = Decl::IDNS_Ordinary;
2035    for (DeclContext::lookup_result Lookup = DC->lookup(Name);
2036         Lookup.first != Lookup.second;
2037         ++Lookup.first) {
2038      if (!(*Lookup.first)->isInIdentifierNamespace(IDNS))
2039        continue;
2040
2041      if (VarDecl *FoundVar = dyn_cast<VarDecl>(*Lookup.first)) {
2042        // We have found a variable that we may need to merge with. Check it.
2043        if (isExternalLinkage(FoundVar->getLinkage()) &&
2044            isExternalLinkage(D->getLinkage())) {
2045          if (Importer.IsStructurallyEquivalent(D->getType(),
2046                                                FoundVar->getType())) {
2047            MergeWithVar = FoundVar;
2048            break;
2049          }
2050
2051          const ArrayType *FoundArray
2052            = Importer.getToContext().getAsArrayType(FoundVar->getType());
2053          const ArrayType *TArray
2054            = Importer.getToContext().getAsArrayType(D->getType());
2055          if (FoundArray && TArray) {
2056            if (isa<IncompleteArrayType>(FoundArray) &&
2057                isa<ConstantArrayType>(TArray)) {
2058              // Import the type.
2059              QualType T = Importer.Import(D->getType());
2060              if (T.isNull())
2061                return 0;
2062
2063              FoundVar->setType(T);
2064              MergeWithVar = FoundVar;
2065              break;
2066            } else if (isa<IncompleteArrayType>(TArray) &&
2067                       isa<ConstantArrayType>(FoundArray)) {
2068              MergeWithVar = FoundVar;
2069              break;
2070            }
2071          }
2072
2073          Importer.ToDiag(Loc, diag::err_odr_variable_type_inconsistent)
2074            << Name << D->getType() << FoundVar->getType();
2075          Importer.ToDiag(FoundVar->getLocation(), diag::note_odr_value_here)
2076            << FoundVar->getType();
2077        }
2078      }
2079
2080      ConflictingDecls.push_back(*Lookup.first);
2081    }
2082
2083    if (MergeWithVar) {
2084      // An equivalent variable with external linkage has been found. Link
2085      // the two declarations, then merge them.
2086      Importer.Imported(D, MergeWithVar);
2087
2088      if (VarDecl *DDef = D->getDefinition()) {
2089        if (VarDecl *ExistingDef = MergeWithVar->getDefinition()) {
2090          Importer.ToDiag(ExistingDef->getLocation(),
2091                          diag::err_odr_variable_multiple_def)
2092            << Name;
2093          Importer.FromDiag(DDef->getLocation(), diag::note_odr_defined_here);
2094        } else {
2095          Expr *Init = Importer.Import(DDef->getInit());
2096          MergeWithVar->setInit(Init);
2097        }
2098      }
2099
2100      return MergeWithVar;
2101    }
2102
2103    if (!ConflictingDecls.empty()) {
2104      Name = Importer.HandleNameConflict(Name, DC, IDNS,
2105                                         ConflictingDecls.data(),
2106                                         ConflictingDecls.size());
2107      if (!Name)
2108        return 0;
2109    }
2110  }
2111
2112  // Import the type.
2113  QualType T = Importer.Import(D->getType());
2114  if (T.isNull())
2115    return 0;
2116
2117  // Create the imported variable.
2118  TypeSourceInfo *TInfo = Importer.Import(D->getTypeSourceInfo());
2119  VarDecl *ToVar = VarDecl::Create(Importer.getToContext(), DC, Loc,
2120                                   Name.getAsIdentifierInfo(), T, TInfo,
2121                                   D->getStorageClass(),
2122                                   D->getStorageClassAsWritten());
2123  // Import the qualifier, if any.
2124  if (D->getQualifier()) {
2125    NestedNameSpecifier *NNS = Importer.Import(D->getQualifier());
2126    SourceRange NNSRange = Importer.Import(D->getQualifierRange());
2127    ToVar->setQualifierInfo(NNS, NNSRange);
2128  }
2129  ToVar->setAccess(D->getAccess());
2130  ToVar->setLexicalDeclContext(LexicalDC);
2131  Importer.Imported(D, ToVar);
2132  LexicalDC->addDecl(ToVar);
2133
2134  // Merge the initializer.
2135  // FIXME: Can we really import any initializer? Alternatively, we could force
2136  // ourselves to import every declaration of a variable and then only use
2137  // getInit() here.
2138  ToVar->setInit(Importer.Import(const_cast<Expr *>(D->getAnyInitializer())));
2139
2140  // FIXME: Other bits to merge?
2141
2142  return ToVar;
2143}
2144
2145Decl *ASTNodeImporter::VisitImplicitParamDecl(ImplicitParamDecl *D) {
2146  // Parameters are created in the translation unit's context, then moved
2147  // into the function declaration's context afterward.
2148  DeclContext *DC = Importer.getToContext().getTranslationUnitDecl();
2149
2150  // Import the name of this declaration.
2151  DeclarationName Name = Importer.Import(D->getDeclName());
2152  if (D->getDeclName() && !Name)
2153    return 0;
2154
2155  // Import the location of this declaration.
2156  SourceLocation Loc = Importer.Import(D->getLocation());
2157
2158  // Import the parameter's type.
2159  QualType T = Importer.Import(D->getType());
2160  if (T.isNull())
2161    return 0;
2162
2163  // Create the imported parameter.
2164  ImplicitParamDecl *ToParm
2165    = ImplicitParamDecl::Create(Importer.getToContext(), DC,
2166                                Loc, Name.getAsIdentifierInfo(),
2167                                T);
2168  return Importer.Imported(D, ToParm);
2169}
2170
2171Decl *ASTNodeImporter::VisitParmVarDecl(ParmVarDecl *D) {
2172  // Parameters are created in the translation unit's context, then moved
2173  // into the function declaration's context afterward.
2174  DeclContext *DC = Importer.getToContext().getTranslationUnitDecl();
2175
2176  // Import the name of this declaration.
2177  DeclarationName Name = Importer.Import(D->getDeclName());
2178  if (D->getDeclName() && !Name)
2179    return 0;
2180
2181  // Import the location of this declaration.
2182  SourceLocation Loc = Importer.Import(D->getLocation());
2183
2184  // Import the parameter's type.
2185  QualType T = Importer.Import(D->getType());
2186  if (T.isNull())
2187    return 0;
2188
2189  // Create the imported parameter.
2190  TypeSourceInfo *TInfo = Importer.Import(D->getTypeSourceInfo());
2191  ParmVarDecl *ToParm = ParmVarDecl::Create(Importer.getToContext(), DC,
2192                                            Loc, Name.getAsIdentifierInfo(),
2193                                            T, TInfo, D->getStorageClass(),
2194                                             D->getStorageClassAsWritten(),
2195                                            /*FIXME: Default argument*/ 0);
2196  ToParm->setHasInheritedDefaultArg(D->hasInheritedDefaultArg());
2197  return Importer.Imported(D, ToParm);
2198}
2199
2200Decl *ASTNodeImporter::VisitObjCMethodDecl(ObjCMethodDecl *D) {
2201  // Import the major distinguishing characteristics of a method.
2202  DeclContext *DC, *LexicalDC;
2203  DeclarationName Name;
2204  SourceLocation Loc;
2205  if (ImportDeclParts(D, DC, LexicalDC, Name, Loc))
2206    return 0;
2207
2208  for (DeclContext::lookup_result Lookup = DC->lookup(Name);
2209       Lookup.first != Lookup.second;
2210       ++Lookup.first) {
2211    if (ObjCMethodDecl *FoundMethod = dyn_cast<ObjCMethodDecl>(*Lookup.first)) {
2212      if (FoundMethod->isInstanceMethod() != D->isInstanceMethod())
2213        continue;
2214
2215      // Check return types.
2216      if (!Importer.IsStructurallyEquivalent(D->getResultType(),
2217                                             FoundMethod->getResultType())) {
2218        Importer.ToDiag(Loc, diag::err_odr_objc_method_result_type_inconsistent)
2219          << D->isInstanceMethod() << Name
2220          << D->getResultType() << FoundMethod->getResultType();
2221        Importer.ToDiag(FoundMethod->getLocation(),
2222                        diag::note_odr_objc_method_here)
2223          << D->isInstanceMethod() << Name;
2224        return 0;
2225      }
2226
2227      // Check the number of parameters.
2228      if (D->param_size() != FoundMethod->param_size()) {
2229        Importer.ToDiag(Loc, diag::err_odr_objc_method_num_params_inconsistent)
2230          << D->isInstanceMethod() << Name
2231          << D->param_size() << FoundMethod->param_size();
2232        Importer.ToDiag(FoundMethod->getLocation(),
2233                        diag::note_odr_objc_method_here)
2234          << D->isInstanceMethod() << Name;
2235        return 0;
2236      }
2237
2238      // Check parameter types.
2239      for (ObjCMethodDecl::param_iterator P = D->param_begin(),
2240             PEnd = D->param_end(), FoundP = FoundMethod->param_begin();
2241           P != PEnd; ++P, ++FoundP) {
2242        if (!Importer.IsStructurallyEquivalent((*P)->getType(),
2243                                               (*FoundP)->getType())) {
2244          Importer.FromDiag((*P)->getLocation(),
2245                            diag::err_odr_objc_method_param_type_inconsistent)
2246            << D->isInstanceMethod() << Name
2247            << (*P)->getType() << (*FoundP)->getType();
2248          Importer.ToDiag((*FoundP)->getLocation(), diag::note_odr_value_here)
2249            << (*FoundP)->getType();
2250          return 0;
2251        }
2252      }
2253
2254      // Check variadic/non-variadic.
2255      // Check the number of parameters.
2256      if (D->isVariadic() != FoundMethod->isVariadic()) {
2257        Importer.ToDiag(Loc, diag::err_odr_objc_method_variadic_inconsistent)
2258          << D->isInstanceMethod() << Name;
2259        Importer.ToDiag(FoundMethod->getLocation(),
2260                        diag::note_odr_objc_method_here)
2261          << D->isInstanceMethod() << Name;
2262        return 0;
2263      }
2264
2265      // FIXME: Any other bits we need to merge?
2266      return Importer.Imported(D, FoundMethod);
2267    }
2268  }
2269
2270  // Import the result type.
2271  QualType ResultTy = Importer.Import(D->getResultType());
2272  if (ResultTy.isNull())
2273    return 0;
2274
2275  TypeSourceInfo *ResultTInfo = Importer.Import(D->getResultTypeSourceInfo());
2276
2277  ObjCMethodDecl *ToMethod
2278    = ObjCMethodDecl::Create(Importer.getToContext(),
2279                             Loc,
2280                             Importer.Import(D->getLocEnd()),
2281                             Name.getObjCSelector(),
2282                             ResultTy, ResultTInfo, DC,
2283                             D->isInstanceMethod(),
2284                             D->isVariadic(),
2285                             D->isSynthesized(),
2286                             D->getImplementationControl());
2287
2288  // FIXME: When we decide to merge method definitions, we'll need to
2289  // deal with implicit parameters.
2290
2291  // Import the parameters
2292  llvm::SmallVector<ParmVarDecl *, 5> ToParams;
2293  for (ObjCMethodDecl::param_iterator FromP = D->param_begin(),
2294                                   FromPEnd = D->param_end();
2295       FromP != FromPEnd;
2296       ++FromP) {
2297    ParmVarDecl *ToP = cast_or_null<ParmVarDecl>(Importer.Import(*FromP));
2298    if (!ToP)
2299      return 0;
2300
2301    ToParams.push_back(ToP);
2302  }
2303
2304  // Set the parameters.
2305  for (unsigned I = 0, N = ToParams.size(); I != N; ++I) {
2306    ToParams[I]->setOwningFunction(ToMethod);
2307    ToMethod->addDecl(ToParams[I]);
2308  }
2309  ToMethod->setMethodParams(Importer.getToContext(),
2310                            ToParams.data(), ToParams.size(),
2311                            ToParams.size());
2312
2313  ToMethod->setLexicalDeclContext(LexicalDC);
2314  Importer.Imported(D, ToMethod);
2315  LexicalDC->addDecl(ToMethod);
2316  return ToMethod;
2317}
2318
2319Decl *ASTNodeImporter::VisitObjCCategoryDecl(ObjCCategoryDecl *D) {
2320  // Import the major distinguishing characteristics of a category.
2321  DeclContext *DC, *LexicalDC;
2322  DeclarationName Name;
2323  SourceLocation Loc;
2324  if (ImportDeclParts(D, DC, LexicalDC, Name, Loc))
2325    return 0;
2326
2327  ObjCInterfaceDecl *ToInterface
2328    = cast_or_null<ObjCInterfaceDecl>(Importer.Import(D->getClassInterface()));
2329  if (!ToInterface)
2330    return 0;
2331
2332  // Determine if we've already encountered this category.
2333  ObjCCategoryDecl *MergeWithCategory
2334    = ToInterface->FindCategoryDeclaration(Name.getAsIdentifierInfo());
2335  ObjCCategoryDecl *ToCategory = MergeWithCategory;
2336  if (!ToCategory) {
2337    ToCategory = ObjCCategoryDecl::Create(Importer.getToContext(), DC,
2338                                          Importer.Import(D->getAtLoc()),
2339                                          Loc,
2340                                       Importer.Import(D->getCategoryNameLoc()),
2341                                          Name.getAsIdentifierInfo());
2342    ToCategory->setLexicalDeclContext(LexicalDC);
2343    LexicalDC->addDecl(ToCategory);
2344    Importer.Imported(D, ToCategory);
2345
2346    // Link this category into its class's category list.
2347    ToCategory->setClassInterface(ToInterface);
2348    ToCategory->insertNextClassCategory();
2349
2350    // Import protocols
2351    llvm::SmallVector<ObjCProtocolDecl *, 4> Protocols;
2352    llvm::SmallVector<SourceLocation, 4> ProtocolLocs;
2353    ObjCCategoryDecl::protocol_loc_iterator FromProtoLoc
2354      = D->protocol_loc_begin();
2355    for (ObjCCategoryDecl::protocol_iterator FromProto = D->protocol_begin(),
2356                                          FromProtoEnd = D->protocol_end();
2357         FromProto != FromProtoEnd;
2358         ++FromProto, ++FromProtoLoc) {
2359      ObjCProtocolDecl *ToProto
2360        = cast_or_null<ObjCProtocolDecl>(Importer.Import(*FromProto));
2361      if (!ToProto)
2362        return 0;
2363      Protocols.push_back(ToProto);
2364      ProtocolLocs.push_back(Importer.Import(*FromProtoLoc));
2365    }
2366
2367    // FIXME: If we're merging, make sure that the protocol list is the same.
2368    ToCategory->setProtocolList(Protocols.data(), Protocols.size(),
2369                                ProtocolLocs.data(), Importer.getToContext());
2370
2371  } else {
2372    Importer.Imported(D, ToCategory);
2373  }
2374
2375  // Import all of the members of this category.
2376  ImportDeclContext(D);
2377
2378  // If we have an implementation, import it as well.
2379  if (D->getImplementation()) {
2380    ObjCCategoryImplDecl *Impl
2381      = cast<ObjCCategoryImplDecl>(Importer.Import(D->getImplementation()));
2382    if (!Impl)
2383      return 0;
2384
2385    ToCategory->setImplementation(Impl);
2386  }
2387
2388  return ToCategory;
2389}
2390
2391Decl *ASTNodeImporter::VisitObjCProtocolDecl(ObjCProtocolDecl *D) {
2392  // Import the major distinguishing characteristics of a protocol.
2393  DeclContext *DC, *LexicalDC;
2394  DeclarationName Name;
2395  SourceLocation Loc;
2396  if (ImportDeclParts(D, DC, LexicalDC, Name, Loc))
2397    return 0;
2398
2399  ObjCProtocolDecl *MergeWithProtocol = 0;
2400  for (DeclContext::lookup_result Lookup = DC->lookup(Name);
2401       Lookup.first != Lookup.second;
2402       ++Lookup.first) {
2403    if (!(*Lookup.first)->isInIdentifierNamespace(Decl::IDNS_ObjCProtocol))
2404      continue;
2405
2406    if ((MergeWithProtocol = dyn_cast<ObjCProtocolDecl>(*Lookup.first)))
2407      break;
2408  }
2409
2410  ObjCProtocolDecl *ToProto = MergeWithProtocol;
2411  if (!ToProto || ToProto->isForwardDecl()) {
2412    if (!ToProto) {
2413      ToProto = ObjCProtocolDecl::Create(Importer.getToContext(), DC, Loc,
2414                                         Name.getAsIdentifierInfo());
2415      ToProto->setForwardDecl(D->isForwardDecl());
2416      ToProto->setLexicalDeclContext(LexicalDC);
2417      LexicalDC->addDecl(ToProto);
2418    }
2419    Importer.Imported(D, ToProto);
2420
2421    // Import protocols
2422    llvm::SmallVector<ObjCProtocolDecl *, 4> Protocols;
2423    llvm::SmallVector<SourceLocation, 4> ProtocolLocs;
2424    ObjCProtocolDecl::protocol_loc_iterator
2425      FromProtoLoc = D->protocol_loc_begin();
2426    for (ObjCProtocolDecl::protocol_iterator FromProto = D->protocol_begin(),
2427                                          FromProtoEnd = D->protocol_end();
2428       FromProto != FromProtoEnd;
2429       ++FromProto, ++FromProtoLoc) {
2430      ObjCProtocolDecl *ToProto
2431        = cast_or_null<ObjCProtocolDecl>(Importer.Import(*FromProto));
2432      if (!ToProto)
2433        return 0;
2434      Protocols.push_back(ToProto);
2435      ProtocolLocs.push_back(Importer.Import(*FromProtoLoc));
2436    }
2437
2438    // FIXME: If we're merging, make sure that the protocol list is the same.
2439    ToProto->setProtocolList(Protocols.data(), Protocols.size(),
2440                             ProtocolLocs.data(), Importer.getToContext());
2441  } else {
2442    Importer.Imported(D, ToProto);
2443  }
2444
2445  // Import all of the members of this protocol.
2446  ImportDeclContext(D);
2447
2448  return ToProto;
2449}
2450
2451Decl *ASTNodeImporter::VisitObjCInterfaceDecl(ObjCInterfaceDecl *D) {
2452  // Import the major distinguishing characteristics of an @interface.
2453  DeclContext *DC, *LexicalDC;
2454  DeclarationName Name;
2455  SourceLocation Loc;
2456  if (ImportDeclParts(D, DC, LexicalDC, Name, Loc))
2457    return 0;
2458
2459  ObjCInterfaceDecl *MergeWithIface = 0;
2460  for (DeclContext::lookup_result Lookup = DC->lookup(Name);
2461       Lookup.first != Lookup.second;
2462       ++Lookup.first) {
2463    if (!(*Lookup.first)->isInIdentifierNamespace(Decl::IDNS_Ordinary))
2464      continue;
2465
2466    if ((MergeWithIface = dyn_cast<ObjCInterfaceDecl>(*Lookup.first)))
2467      break;
2468  }
2469
2470  ObjCInterfaceDecl *ToIface = MergeWithIface;
2471  if (!ToIface || ToIface->isForwardDecl()) {
2472    if (!ToIface) {
2473      ToIface = ObjCInterfaceDecl::Create(Importer.getToContext(),
2474                                          DC, Loc,
2475                                          Name.getAsIdentifierInfo(),
2476                                          Importer.Import(D->getClassLoc()),
2477                                          D->isForwardDecl(),
2478                                          D->isImplicitInterfaceDecl());
2479      ToIface->setForwardDecl(D->isForwardDecl());
2480      ToIface->setLexicalDeclContext(LexicalDC);
2481      LexicalDC->addDecl(ToIface);
2482    }
2483    Importer.Imported(D, ToIface);
2484
2485    if (D->getSuperClass()) {
2486      ObjCInterfaceDecl *Super
2487        = cast_or_null<ObjCInterfaceDecl>(Importer.Import(D->getSuperClass()));
2488      if (!Super)
2489        return 0;
2490
2491      ToIface->setSuperClass(Super);
2492      ToIface->setSuperClassLoc(Importer.Import(D->getSuperClassLoc()));
2493    }
2494
2495    // Import protocols
2496    llvm::SmallVector<ObjCProtocolDecl *, 4> Protocols;
2497    llvm::SmallVector<SourceLocation, 4> ProtocolLocs;
2498    ObjCInterfaceDecl::protocol_loc_iterator
2499      FromProtoLoc = D->protocol_loc_begin();
2500    for (ObjCInterfaceDecl::protocol_iterator FromProto = D->protocol_begin(),
2501                                           FromProtoEnd = D->protocol_end();
2502       FromProto != FromProtoEnd;
2503       ++FromProto, ++FromProtoLoc) {
2504      ObjCProtocolDecl *ToProto
2505        = cast_or_null<ObjCProtocolDecl>(Importer.Import(*FromProto));
2506      if (!ToProto)
2507        return 0;
2508      Protocols.push_back(ToProto);
2509      ProtocolLocs.push_back(Importer.Import(*FromProtoLoc));
2510    }
2511
2512    // FIXME: If we're merging, make sure that the protocol list is the same.
2513    ToIface->setProtocolList(Protocols.data(), Protocols.size(),
2514                             ProtocolLocs.data(), Importer.getToContext());
2515
2516    // Import @end range
2517    ToIface->setAtEndRange(Importer.Import(D->getAtEndRange()));
2518  } else {
2519    Importer.Imported(D, ToIface);
2520
2521    // Check for consistency of superclasses.
2522    DeclarationName FromSuperName, ToSuperName;
2523    if (D->getSuperClass())
2524      FromSuperName = Importer.Import(D->getSuperClass()->getDeclName());
2525    if (ToIface->getSuperClass())
2526      ToSuperName = ToIface->getSuperClass()->getDeclName();
2527    if (FromSuperName != ToSuperName) {
2528      Importer.ToDiag(ToIface->getLocation(),
2529                      diag::err_odr_objc_superclass_inconsistent)
2530        << ToIface->getDeclName();
2531      if (ToIface->getSuperClass())
2532        Importer.ToDiag(ToIface->getSuperClassLoc(),
2533                        diag::note_odr_objc_superclass)
2534          << ToIface->getSuperClass()->getDeclName();
2535      else
2536        Importer.ToDiag(ToIface->getLocation(),
2537                        diag::note_odr_objc_missing_superclass);
2538      if (D->getSuperClass())
2539        Importer.FromDiag(D->getSuperClassLoc(),
2540                          diag::note_odr_objc_superclass)
2541          << D->getSuperClass()->getDeclName();
2542      else
2543        Importer.FromDiag(D->getLocation(),
2544                          diag::note_odr_objc_missing_superclass);
2545      return 0;
2546    }
2547  }
2548
2549  // Import categories. When the categories themselves are imported, they'll
2550  // hook themselves into this interface.
2551  for (ObjCCategoryDecl *FromCat = D->getCategoryList(); FromCat;
2552       FromCat = FromCat->getNextClassCategory())
2553    Importer.Import(FromCat);
2554
2555  // Import all of the members of this class.
2556  ImportDeclContext(D);
2557
2558  // If we have an @implementation, import it as well.
2559  if (D->getImplementation()) {
2560    ObjCImplementationDecl *Impl
2561      = cast<ObjCImplementationDecl>(Importer.Import(D->getImplementation()));
2562    if (!Impl)
2563      return 0;
2564
2565    ToIface->setImplementation(Impl);
2566  }
2567
2568  return ToIface;
2569}
2570
2571Decl *ASTNodeImporter::VisitObjCPropertyDecl(ObjCPropertyDecl *D) {
2572  // Import the major distinguishing characteristics of an @property.
2573  DeclContext *DC, *LexicalDC;
2574  DeclarationName Name;
2575  SourceLocation Loc;
2576  if (ImportDeclParts(D, DC, LexicalDC, Name, Loc))
2577    return 0;
2578
2579  // Check whether we have already imported this property.
2580  for (DeclContext::lookup_result Lookup = DC->lookup(Name);
2581       Lookup.first != Lookup.second;
2582       ++Lookup.first) {
2583    if (ObjCPropertyDecl *FoundProp
2584                                = dyn_cast<ObjCPropertyDecl>(*Lookup.first)) {
2585      // Check property types.
2586      if (!Importer.IsStructurallyEquivalent(D->getType(),
2587                                             FoundProp->getType())) {
2588        Importer.ToDiag(Loc, diag::err_odr_objc_property_type_inconsistent)
2589          << Name << D->getType() << FoundProp->getType();
2590        Importer.ToDiag(FoundProp->getLocation(), diag::note_odr_value_here)
2591          << FoundProp->getType();
2592        return 0;
2593      }
2594
2595      // FIXME: Check property attributes, getters, setters, etc.?
2596
2597      // Consider these properties to be equivalent.
2598      Importer.Imported(D, FoundProp);
2599      return FoundProp;
2600    }
2601  }
2602
2603  // Import the type.
2604  TypeSourceInfo *T = Importer.Import(D->getTypeSourceInfo());
2605  if (!T)
2606    return 0;
2607
2608  // Create the new property.
2609  ObjCPropertyDecl *ToProperty
2610    = ObjCPropertyDecl::Create(Importer.getToContext(), DC, Loc,
2611                               Name.getAsIdentifierInfo(),
2612                               Importer.Import(D->getAtLoc()),
2613                               T,
2614                               D->getPropertyImplementation());
2615  Importer.Imported(D, ToProperty);
2616  ToProperty->setLexicalDeclContext(LexicalDC);
2617  LexicalDC->addDecl(ToProperty);
2618
2619  ToProperty->setPropertyAttributes(D->getPropertyAttributes());
2620  ToProperty->setGetterName(Importer.Import(D->getGetterName()));
2621  ToProperty->setSetterName(Importer.Import(D->getSetterName()));
2622  ToProperty->setGetterMethodDecl(
2623     cast_or_null<ObjCMethodDecl>(Importer.Import(D->getGetterMethodDecl())));
2624  ToProperty->setSetterMethodDecl(
2625     cast_or_null<ObjCMethodDecl>(Importer.Import(D->getSetterMethodDecl())));
2626  ToProperty->setPropertyIvarDecl(
2627       cast_or_null<ObjCIvarDecl>(Importer.Import(D->getPropertyIvarDecl())));
2628  return ToProperty;
2629}
2630
2631Decl *
2632ASTNodeImporter::VisitObjCForwardProtocolDecl(ObjCForwardProtocolDecl *D) {
2633  // Import the context of this declaration.
2634  DeclContext *DC = Importer.ImportContext(D->getDeclContext());
2635  if (!DC)
2636    return 0;
2637
2638  DeclContext *LexicalDC = DC;
2639  if (D->getDeclContext() != D->getLexicalDeclContext()) {
2640    LexicalDC = Importer.ImportContext(D->getLexicalDeclContext());
2641    if (!LexicalDC)
2642      return 0;
2643  }
2644
2645  // Import the location of this declaration.
2646  SourceLocation Loc = Importer.Import(D->getLocation());
2647
2648  llvm::SmallVector<ObjCProtocolDecl *, 4> Protocols;
2649  llvm::SmallVector<SourceLocation, 4> Locations;
2650  ObjCForwardProtocolDecl::protocol_loc_iterator FromProtoLoc
2651    = D->protocol_loc_begin();
2652  for (ObjCForwardProtocolDecl::protocol_iterator FromProto
2653         = D->protocol_begin(), FromProtoEnd = D->protocol_end();
2654       FromProto != FromProtoEnd;
2655       ++FromProto, ++FromProtoLoc) {
2656    ObjCProtocolDecl *ToProto
2657      = cast_or_null<ObjCProtocolDecl>(Importer.Import(*FromProto));
2658    if (!ToProto)
2659      continue;
2660
2661    Protocols.push_back(ToProto);
2662    Locations.push_back(Importer.Import(*FromProtoLoc));
2663  }
2664
2665  ObjCForwardProtocolDecl *ToForward
2666    = ObjCForwardProtocolDecl::Create(Importer.getToContext(), DC, Loc,
2667                                      Protocols.data(), Protocols.size(),
2668                                      Locations.data());
2669  ToForward->setLexicalDeclContext(LexicalDC);
2670  LexicalDC->addDecl(ToForward);
2671  Importer.Imported(D, ToForward);
2672  return ToForward;
2673}
2674
2675Decl *ASTNodeImporter::VisitObjCClassDecl(ObjCClassDecl *D) {
2676  // Import the context of this declaration.
2677  DeclContext *DC = Importer.ImportContext(D->getDeclContext());
2678  if (!DC)
2679    return 0;
2680
2681  DeclContext *LexicalDC = DC;
2682  if (D->getDeclContext() != D->getLexicalDeclContext()) {
2683    LexicalDC = Importer.ImportContext(D->getLexicalDeclContext());
2684    if (!LexicalDC)
2685      return 0;
2686  }
2687
2688  // Import the location of this declaration.
2689  SourceLocation Loc = Importer.Import(D->getLocation());
2690
2691  llvm::SmallVector<ObjCInterfaceDecl *, 4> Interfaces;
2692  llvm::SmallVector<SourceLocation, 4> Locations;
2693  for (ObjCClassDecl::iterator From = D->begin(), FromEnd = D->end();
2694       From != FromEnd; ++From) {
2695    ObjCInterfaceDecl *ToIface
2696      = cast_or_null<ObjCInterfaceDecl>(Importer.Import(From->getInterface()));
2697    if (!ToIface)
2698      continue;
2699
2700    Interfaces.push_back(ToIface);
2701    Locations.push_back(Importer.Import(From->getLocation()));
2702  }
2703
2704  ObjCClassDecl *ToClass = ObjCClassDecl::Create(Importer.getToContext(), DC,
2705                                                 Loc,
2706                                                 Interfaces.data(),
2707                                                 Locations.data(),
2708                                                 Interfaces.size());
2709  ToClass->setLexicalDeclContext(LexicalDC);
2710  LexicalDC->addDecl(ToClass);
2711  Importer.Imported(D, ToClass);
2712  return ToClass;
2713}
2714
2715//----------------------------------------------------------------------------
2716// Import Statements
2717//----------------------------------------------------------------------------
2718
2719Stmt *ASTNodeImporter::VisitStmt(Stmt *S) {
2720  Importer.FromDiag(S->getLocStart(), diag::err_unsupported_ast_node)
2721    << S->getStmtClassName();
2722  return 0;
2723}
2724
2725//----------------------------------------------------------------------------
2726// Import Expressions
2727//----------------------------------------------------------------------------
2728Expr *ASTNodeImporter::VisitExpr(Expr *E) {
2729  Importer.FromDiag(E->getLocStart(), diag::err_unsupported_ast_node)
2730    << E->getStmtClassName();
2731  return 0;
2732}
2733
2734Expr *ASTNodeImporter::VisitDeclRefExpr(DeclRefExpr *E) {
2735  NestedNameSpecifier *Qualifier = 0;
2736  if (E->getQualifier()) {
2737    Qualifier = Importer.Import(E->getQualifier());
2738    if (!E->getQualifier())
2739      return 0;
2740  }
2741
2742  ValueDecl *ToD = cast_or_null<ValueDecl>(Importer.Import(E->getDecl()));
2743  if (!ToD)
2744    return 0;
2745
2746  QualType T = Importer.Import(E->getType());
2747  if (T.isNull())
2748    return 0;
2749
2750  return DeclRefExpr::Create(Importer.getToContext(), Qualifier,
2751                             Importer.Import(E->getQualifierRange()),
2752                             ToD,
2753                             Importer.Import(E->getLocation()),
2754                             T,
2755                             /*FIXME:TemplateArgs=*/0);
2756}
2757
2758Expr *ASTNodeImporter::VisitIntegerLiteral(IntegerLiteral *E) {
2759  QualType T = Importer.Import(E->getType());
2760  if (T.isNull())
2761    return 0;
2762
2763  return new (Importer.getToContext())
2764    IntegerLiteral(E->getValue(), T, Importer.Import(E->getLocation()));
2765}
2766
2767Expr *ASTNodeImporter::VisitCharacterLiteral(CharacterLiteral *E) {
2768  QualType T = Importer.Import(E->getType());
2769  if (T.isNull())
2770    return 0;
2771
2772  return new (Importer.getToContext()) CharacterLiteral(E->getValue(),
2773                                                        E->isWide(), T,
2774                                          Importer.Import(E->getLocation()));
2775}
2776
2777Expr *ASTNodeImporter::VisitParenExpr(ParenExpr *E) {
2778  Expr *SubExpr = Importer.Import(E->getSubExpr());
2779  if (!SubExpr)
2780    return 0;
2781
2782  return new (Importer.getToContext())
2783                                  ParenExpr(Importer.Import(E->getLParen()),
2784                                            Importer.Import(E->getRParen()),
2785                                            SubExpr);
2786}
2787
2788Expr *ASTNodeImporter::VisitUnaryOperator(UnaryOperator *E) {
2789  QualType T = Importer.Import(E->getType());
2790  if (T.isNull())
2791    return 0;
2792
2793  Expr *SubExpr = Importer.Import(E->getSubExpr());
2794  if (!SubExpr)
2795    return 0;
2796
2797  return new (Importer.getToContext()) UnaryOperator(SubExpr, E->getOpcode(),
2798                                                     T,
2799                                         Importer.Import(E->getOperatorLoc()));
2800}
2801
2802Expr *ASTNodeImporter::VisitSizeOfAlignOfExpr(SizeOfAlignOfExpr *E) {
2803  QualType ResultType = Importer.Import(E->getType());
2804
2805  if (E->isArgumentType()) {
2806    TypeSourceInfo *TInfo = Importer.Import(E->getArgumentTypeInfo());
2807    if (!TInfo)
2808      return 0;
2809
2810    return new (Importer.getToContext()) SizeOfAlignOfExpr(E->isSizeOf(),
2811                                                           TInfo, ResultType,
2812                                           Importer.Import(E->getOperatorLoc()),
2813                                           Importer.Import(E->getRParenLoc()));
2814  }
2815
2816  Expr *SubExpr = Importer.Import(E->getArgumentExpr());
2817  if (!SubExpr)
2818    return 0;
2819
2820  return new (Importer.getToContext()) SizeOfAlignOfExpr(E->isSizeOf(),
2821                                                         SubExpr, ResultType,
2822                                          Importer.Import(E->getOperatorLoc()),
2823                                          Importer.Import(E->getRParenLoc()));
2824}
2825
2826Expr *ASTNodeImporter::VisitBinaryOperator(BinaryOperator *E) {
2827  QualType T = Importer.Import(E->getType());
2828  if (T.isNull())
2829    return 0;
2830
2831  Expr *LHS = Importer.Import(E->getLHS());
2832  if (!LHS)
2833    return 0;
2834
2835  Expr *RHS = Importer.Import(E->getRHS());
2836  if (!RHS)
2837    return 0;
2838
2839  return new (Importer.getToContext()) BinaryOperator(LHS, RHS, E->getOpcode(),
2840                                                      T,
2841                                          Importer.Import(E->getOperatorLoc()));
2842}
2843
2844Expr *ASTNodeImporter::VisitCompoundAssignOperator(CompoundAssignOperator *E) {
2845  QualType T = Importer.Import(E->getType());
2846  if (T.isNull())
2847    return 0;
2848
2849  QualType CompLHSType = Importer.Import(E->getComputationLHSType());
2850  if (CompLHSType.isNull())
2851    return 0;
2852
2853  QualType CompResultType = Importer.Import(E->getComputationResultType());
2854  if (CompResultType.isNull())
2855    return 0;
2856
2857  Expr *LHS = Importer.Import(E->getLHS());
2858  if (!LHS)
2859    return 0;
2860
2861  Expr *RHS = Importer.Import(E->getRHS());
2862  if (!RHS)
2863    return 0;
2864
2865  return new (Importer.getToContext())
2866                        CompoundAssignOperator(LHS, RHS, E->getOpcode(),
2867                                               T, CompLHSType, CompResultType,
2868                                          Importer.Import(E->getOperatorLoc()));
2869}
2870
2871Expr *ASTNodeImporter::VisitImplicitCastExpr(ImplicitCastExpr *E) {
2872  QualType T = Importer.Import(E->getType());
2873  if (T.isNull())
2874    return 0;
2875
2876  Expr *SubExpr = Importer.Import(E->getSubExpr());
2877  if (!SubExpr)
2878    return 0;
2879
2880  // FIXME: Initialize the base path.
2881  assert(E->getBasePath().empty() && "FIXME: Must copy base path!");
2882  CXXBaseSpecifierArray BasePath;
2883  return new (Importer.getToContext()) ImplicitCastExpr(T, E->getCastKind(),
2884                                                        SubExpr, BasePath,
2885                                                        E->isLvalueCast());
2886}
2887
2888Expr *ASTNodeImporter::VisitCStyleCastExpr(CStyleCastExpr *E) {
2889  QualType T = Importer.Import(E->getType());
2890  if (T.isNull())
2891    return 0;
2892
2893  Expr *SubExpr = Importer.Import(E->getSubExpr());
2894  if (!SubExpr)
2895    return 0;
2896
2897  TypeSourceInfo *TInfo = Importer.Import(E->getTypeInfoAsWritten());
2898  if (!TInfo && E->getTypeInfoAsWritten())
2899    return 0;
2900
2901  // FIXME: Initialize the base path.
2902  assert(E->getBasePath().empty() && "FIXME: Must copy base path!");
2903  CXXBaseSpecifierArray BasePath;
2904  return new (Importer.getToContext()) CStyleCastExpr(T, E->getCastKind(),
2905                                                      SubExpr, BasePath, TInfo,
2906                                            Importer.Import(E->getLParenLoc()),
2907                                            Importer.Import(E->getRParenLoc()));
2908}
2909
2910ASTImporter::ASTImporter(Diagnostic &Diags,
2911                         ASTContext &ToContext, FileManager &ToFileManager,
2912                         ASTContext &FromContext, FileManager &FromFileManager)
2913  : ToContext(ToContext), FromContext(FromContext),
2914    ToFileManager(ToFileManager), FromFileManager(FromFileManager),
2915    Diags(Diags) {
2916  ImportedDecls[FromContext.getTranslationUnitDecl()]
2917    = ToContext.getTranslationUnitDecl();
2918}
2919
2920ASTImporter::~ASTImporter() { }
2921
2922QualType ASTImporter::Import(QualType FromT) {
2923  if (FromT.isNull())
2924    return QualType();
2925
2926  // Check whether we've already imported this type.
2927  llvm::DenseMap<Type *, Type *>::iterator Pos
2928    = ImportedTypes.find(FromT.getTypePtr());
2929  if (Pos != ImportedTypes.end())
2930    return ToContext.getQualifiedType(Pos->second, FromT.getQualifiers());
2931
2932  // Import the type
2933  ASTNodeImporter Importer(*this);
2934  QualType ToT = Importer.Visit(FromT.getTypePtr());
2935  if (ToT.isNull())
2936    return ToT;
2937
2938  // Record the imported type.
2939  ImportedTypes[FromT.getTypePtr()] = ToT.getTypePtr();
2940
2941  return ToContext.getQualifiedType(ToT, FromT.getQualifiers());
2942}
2943
2944TypeSourceInfo *ASTImporter::Import(TypeSourceInfo *FromTSI) {
2945  if (!FromTSI)
2946    return FromTSI;
2947
2948  // FIXME: For now we just create a "trivial" type source info based
2949  // on the type and a seingle location. Implement a real version of
2950  // this.
2951  QualType T = Import(FromTSI->getType());
2952  if (T.isNull())
2953    return 0;
2954
2955  return ToContext.getTrivialTypeSourceInfo(T,
2956                        FromTSI->getTypeLoc().getSourceRange().getBegin());
2957}
2958
2959Decl *ASTImporter::Import(Decl *FromD) {
2960  if (!FromD)
2961    return 0;
2962
2963  // Check whether we've already imported this declaration.
2964  llvm::DenseMap<Decl *, Decl *>::iterator Pos = ImportedDecls.find(FromD);
2965  if (Pos != ImportedDecls.end())
2966    return Pos->second;
2967
2968  // Import the type
2969  ASTNodeImporter Importer(*this);
2970  Decl *ToD = Importer.Visit(FromD);
2971  if (!ToD)
2972    return 0;
2973
2974  // Record the imported declaration.
2975  ImportedDecls[FromD] = ToD;
2976
2977  if (TagDecl *FromTag = dyn_cast<TagDecl>(FromD)) {
2978    // Keep track of anonymous tags that have an associated typedef.
2979    if (FromTag->getTypedefForAnonDecl())
2980      AnonTagsWithPendingTypedefs.push_back(FromTag);
2981  } else if (TypedefDecl *FromTypedef = dyn_cast<TypedefDecl>(FromD)) {
2982    // When we've finished transforming a typedef, see whether it was the
2983    // typedef for an anonymous tag.
2984    for (llvm::SmallVector<TagDecl *, 4>::iterator
2985               FromTag = AnonTagsWithPendingTypedefs.begin(),
2986            FromTagEnd = AnonTagsWithPendingTypedefs.end();
2987         FromTag != FromTagEnd; ++FromTag) {
2988      if ((*FromTag)->getTypedefForAnonDecl() == FromTypedef) {
2989        if (TagDecl *ToTag = cast_or_null<TagDecl>(Import(*FromTag))) {
2990          // We found the typedef for an anonymous tag; link them.
2991          ToTag->setTypedefForAnonDecl(cast<TypedefDecl>(ToD));
2992          AnonTagsWithPendingTypedefs.erase(FromTag);
2993          break;
2994        }
2995      }
2996    }
2997  }
2998
2999  return ToD;
3000}
3001
3002DeclContext *ASTImporter::ImportContext(DeclContext *FromDC) {
3003  if (!FromDC)
3004    return FromDC;
3005
3006  return cast_or_null<DeclContext>(Import(cast<Decl>(FromDC)));
3007}
3008
3009Expr *ASTImporter::Import(Expr *FromE) {
3010  if (!FromE)
3011    return 0;
3012
3013  return cast_or_null<Expr>(Import(cast<Stmt>(FromE)));
3014}
3015
3016Stmt *ASTImporter::Import(Stmt *FromS) {
3017  if (!FromS)
3018    return 0;
3019
3020  // Check whether we've already imported this declaration.
3021  llvm::DenseMap<Stmt *, Stmt *>::iterator Pos = ImportedStmts.find(FromS);
3022  if (Pos != ImportedStmts.end())
3023    return Pos->second;
3024
3025  // Import the type
3026  ASTNodeImporter Importer(*this);
3027  Stmt *ToS = Importer.Visit(FromS);
3028  if (!ToS)
3029    return 0;
3030
3031  // Record the imported declaration.
3032  ImportedStmts[FromS] = ToS;
3033  return ToS;
3034}
3035
3036NestedNameSpecifier *ASTImporter::Import(NestedNameSpecifier *FromNNS) {
3037  if (!FromNNS)
3038    return 0;
3039
3040  // FIXME: Implement!
3041  return 0;
3042}
3043
3044SourceLocation ASTImporter::Import(SourceLocation FromLoc) {
3045  if (FromLoc.isInvalid())
3046    return SourceLocation();
3047
3048  SourceManager &FromSM = FromContext.getSourceManager();
3049
3050  // For now, map everything down to its spelling location, so that we
3051  // don't have to import macro instantiations.
3052  // FIXME: Import macro instantiations!
3053  FromLoc = FromSM.getSpellingLoc(FromLoc);
3054  std::pair<FileID, unsigned> Decomposed = FromSM.getDecomposedLoc(FromLoc);
3055  SourceManager &ToSM = ToContext.getSourceManager();
3056  return ToSM.getLocForStartOfFile(Import(Decomposed.first))
3057             .getFileLocWithOffset(Decomposed.second);
3058}
3059
3060SourceRange ASTImporter::Import(SourceRange FromRange) {
3061  return SourceRange(Import(FromRange.getBegin()), Import(FromRange.getEnd()));
3062}
3063
3064FileID ASTImporter::Import(FileID FromID) {
3065  llvm::DenseMap<unsigned, FileID>::iterator Pos
3066    = ImportedFileIDs.find(FromID.getHashValue());
3067  if (Pos != ImportedFileIDs.end())
3068    return Pos->second;
3069
3070  SourceManager &FromSM = FromContext.getSourceManager();
3071  SourceManager &ToSM = ToContext.getSourceManager();
3072  const SrcMgr::SLocEntry &FromSLoc = FromSM.getSLocEntry(FromID);
3073  assert(FromSLoc.isFile() && "Cannot handle macro instantiations yet");
3074
3075  // Include location of this file.
3076  SourceLocation ToIncludeLoc = Import(FromSLoc.getFile().getIncludeLoc());
3077
3078  // Map the FileID for to the "to" source manager.
3079  FileID ToID;
3080  const SrcMgr::ContentCache *Cache = FromSLoc.getFile().getContentCache();
3081  if (Cache->Entry) {
3082    // FIXME: We probably want to use getVirtualFile(), so we don't hit the
3083    // disk again
3084    // FIXME: We definitely want to re-use the existing MemoryBuffer, rather
3085    // than mmap the files several times.
3086    const FileEntry *Entry = ToFileManager.getFile(Cache->Entry->getName());
3087    ToID = ToSM.createFileID(Entry, ToIncludeLoc,
3088                             FromSLoc.getFile().getFileCharacteristic());
3089  } else {
3090    // FIXME: We want to re-use the existing MemoryBuffer!
3091    const llvm::MemoryBuffer *FromBuf = Cache->getBuffer(getDiags(), FromSM);
3092    llvm::MemoryBuffer *ToBuf
3093      = llvm::MemoryBuffer::getMemBufferCopy(FromBuf->getBuffer(),
3094                                             FromBuf->getBufferIdentifier());
3095    ToID = ToSM.createFileIDForMemBuffer(ToBuf);
3096  }
3097
3098
3099  ImportedFileIDs[FromID.getHashValue()] = ToID;
3100  return ToID;
3101}
3102
3103DeclarationName ASTImporter::Import(DeclarationName FromName) {
3104  if (!FromName)
3105    return DeclarationName();
3106
3107  switch (FromName.getNameKind()) {
3108  case DeclarationName::Identifier:
3109    return Import(FromName.getAsIdentifierInfo());
3110
3111  case DeclarationName::ObjCZeroArgSelector:
3112  case DeclarationName::ObjCOneArgSelector:
3113  case DeclarationName::ObjCMultiArgSelector:
3114    return Import(FromName.getObjCSelector());
3115
3116  case DeclarationName::CXXConstructorName: {
3117    QualType T = Import(FromName.getCXXNameType());
3118    if (T.isNull())
3119      return DeclarationName();
3120
3121    return ToContext.DeclarationNames.getCXXConstructorName(
3122                                               ToContext.getCanonicalType(T));
3123  }
3124
3125  case DeclarationName::CXXDestructorName: {
3126    QualType T = Import(FromName.getCXXNameType());
3127    if (T.isNull())
3128      return DeclarationName();
3129
3130    return ToContext.DeclarationNames.getCXXDestructorName(
3131                                               ToContext.getCanonicalType(T));
3132  }
3133
3134  case DeclarationName::CXXConversionFunctionName: {
3135    QualType T = Import(FromName.getCXXNameType());
3136    if (T.isNull())
3137      return DeclarationName();
3138
3139    return ToContext.DeclarationNames.getCXXConversionFunctionName(
3140                                               ToContext.getCanonicalType(T));
3141  }
3142
3143  case DeclarationName::CXXOperatorName:
3144    return ToContext.DeclarationNames.getCXXOperatorName(
3145                                          FromName.getCXXOverloadedOperator());
3146
3147  case DeclarationName::CXXLiteralOperatorName:
3148    return ToContext.DeclarationNames.getCXXLiteralOperatorName(
3149                                   Import(FromName.getCXXLiteralIdentifier()));
3150
3151  case DeclarationName::CXXUsingDirective:
3152    // FIXME: STATICS!
3153    return DeclarationName::getUsingDirectiveName();
3154  }
3155
3156  // Silence bogus GCC warning
3157  return DeclarationName();
3158}
3159
3160IdentifierInfo *ASTImporter::Import(IdentifierInfo *FromId) {
3161  if (!FromId)
3162    return 0;
3163
3164  return &ToContext.Idents.get(FromId->getName());
3165}
3166
3167Selector ASTImporter::Import(Selector FromSel) {
3168  if (FromSel.isNull())
3169    return Selector();
3170
3171  llvm::SmallVector<IdentifierInfo *, 4> Idents;
3172  Idents.push_back(Import(FromSel.getIdentifierInfoForSlot(0)));
3173  for (unsigned I = 1, N = FromSel.getNumArgs(); I < N; ++I)
3174    Idents.push_back(Import(FromSel.getIdentifierInfoForSlot(I)));
3175  return ToContext.Selectors.getSelector(FromSel.getNumArgs(), Idents.data());
3176}
3177
3178DeclarationName ASTImporter::HandleNameConflict(DeclarationName Name,
3179                                                DeclContext *DC,
3180                                                unsigned IDNS,
3181                                                NamedDecl **Decls,
3182                                                unsigned NumDecls) {
3183  return Name;
3184}
3185
3186DiagnosticBuilder ASTImporter::ToDiag(SourceLocation Loc, unsigned DiagID) {
3187  return Diags.Report(FullSourceLoc(Loc, ToContext.getSourceManager()),
3188                      DiagID);
3189}
3190
3191DiagnosticBuilder ASTImporter::FromDiag(SourceLocation Loc, unsigned DiagID) {
3192  return Diags.Report(FullSourceLoc(Loc, FromContext.getSourceManager()),
3193                      DiagID);
3194}
3195
3196Decl *ASTImporter::Imported(Decl *From, Decl *To) {
3197  ImportedDecls[From] = To;
3198  return To;
3199}
3200
3201bool ASTImporter::IsStructurallyEquivalent(QualType From, QualType To) {
3202  llvm::DenseMap<Type *, Type *>::iterator Pos
3203   = ImportedTypes.find(From.getTypePtr());
3204  if (Pos != ImportedTypes.end() && ToContext.hasSameType(Import(From), To))
3205    return true;
3206
3207  StructuralEquivalenceContext Ctx(FromContext, ToContext, Diags,
3208                                   NonEquivalentDecls);
3209  return Ctx.IsStructurallyEquivalent(From, To);
3210}
3211