SemaDeclObjC.cpp revision 06cf8c47e850e25a32f49e0a7f7ef075d1ec8b6b 
1//===--- SemaDeclObjC.cpp - Semantic Analysis for ObjC Declarations -------===//
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 implements semantic analysis for Objective C declarations.
11//
12//===----------------------------------------------------------------------===//
13
14#include "Sema.h"
15#include "Lookup.h"
16#include "clang/Sema/ExternalSemaSource.h"
17#include "clang/AST/Expr.h"
18#include "clang/AST/ASTContext.h"
19#include "clang/AST/DeclObjC.h"
20#include "clang/Parse/DeclSpec.h"
21using namespace clang;
22
23/// ActOnStartOfObjCMethodDef - This routine sets up parameters; invisible
24/// and user declared, in the method definition's AST.
25void Sema::ActOnStartOfObjCMethodDef(Scope *FnBodyScope, DeclPtrTy D) {
26  assert(getCurMethodDecl() == 0 && "Method parsing confused");
27  ObjCMethodDecl *MDecl = dyn_cast_or_null<ObjCMethodDecl>(D.getAs<Decl>());
28
29  // If we don't have a valid method decl, simply return.
30  if (!MDecl)
31    return;
32
33  // Allow the rest of sema to find private method decl implementations.
34  if (MDecl->isInstanceMethod())
35    AddInstanceMethodToGlobalPool(MDecl);
36  else
37    AddFactoryMethodToGlobalPool(MDecl);
38
39  // Allow all of Sema to see that we are entering a method definition.
40  PushDeclContext(FnBodyScope, MDecl);
41  PushFunctionScope();
42
43  // Create Decl objects for each parameter, entrring them in the scope for
44  // binding to their use.
45
46  // Insert the invisible arguments, self and _cmd!
47  MDecl->createImplicitParams(Context, MDecl->getClassInterface());
48
49  PushOnScopeChains(MDecl->getSelfDecl(), FnBodyScope);
50  PushOnScopeChains(MDecl->getCmdDecl(), FnBodyScope);
51
52  // Introduce all of the other parameters into this scope.
53  for (ObjCMethodDecl::param_iterator PI = MDecl->param_begin(),
54       E = MDecl->param_end(); PI != E; ++PI)
55    if ((*PI)->getIdentifier())
56      PushOnScopeChains(*PI, FnBodyScope);
57}
58
59Sema::DeclPtrTy Sema::
60ActOnStartClassInterface(SourceLocation AtInterfaceLoc,
61                         IdentifierInfo *ClassName, SourceLocation ClassLoc,
62                         IdentifierInfo *SuperName, SourceLocation SuperLoc,
63                         const DeclPtrTy *ProtoRefs, unsigned NumProtoRefs,
64                         const SourceLocation *ProtoLocs,
65                         SourceLocation EndProtoLoc, AttributeList *AttrList) {
66  assert(ClassName && "Missing class identifier");
67
68  // Check for another declaration kind with the same name.
69  NamedDecl *PrevDecl = LookupSingleName(TUScope, ClassName, LookupOrdinaryName);
70  if (PrevDecl && PrevDecl->isTemplateParameter()) {
71    // Maybe we will complain about the shadowed template parameter.
72    DiagnoseTemplateParameterShadow(ClassLoc, PrevDecl);
73    // Just pretend that we didn't see the previous declaration.
74    PrevDecl = 0;
75  }
76
77  if (PrevDecl && !isa<ObjCInterfaceDecl>(PrevDecl)) {
78    Diag(ClassLoc, diag::err_redefinition_different_kind) << ClassName;
79    Diag(PrevDecl->getLocation(), diag::note_previous_definition);
80  }
81
82  ObjCInterfaceDecl* IDecl = dyn_cast_or_null<ObjCInterfaceDecl>(PrevDecl);
83  if (IDecl) {
84    // Class already seen. Is it a forward declaration?
85    if (!IDecl->isForwardDecl()) {
86      IDecl->setInvalidDecl();
87      Diag(AtInterfaceLoc, diag::err_duplicate_class_def)<<IDecl->getDeclName();
88      Diag(IDecl->getLocation(), diag::note_previous_definition);
89
90      // Return the previous class interface.
91      // FIXME: don't leak the objects passed in!
92      return DeclPtrTy::make(IDecl);
93    } else {
94      IDecl->setLocation(AtInterfaceLoc);
95      IDecl->setForwardDecl(false);
96      IDecl->setClassLoc(ClassLoc);
97
98      // Since this ObjCInterfaceDecl was created by a forward declaration,
99      // we now add it to the DeclContext since it wasn't added before
100      // (see ActOnForwardClassDeclaration).
101      CurContext->addDecl(IDecl);
102
103      if (AttrList)
104        ProcessDeclAttributeList(TUScope, IDecl, AttrList);
105    }
106  } else {
107    IDecl = ObjCInterfaceDecl::Create(Context, CurContext, AtInterfaceLoc,
108                                      ClassName, ClassLoc);
109    if (AttrList)
110      ProcessDeclAttributeList(TUScope, IDecl, AttrList);
111
112    PushOnScopeChains(IDecl, TUScope);
113  }
114
115  if (SuperName) {
116    // Check if a different kind of symbol declared in this scope.
117    PrevDecl = LookupSingleName(TUScope, SuperName, LookupOrdinaryName);
118
119    if (!PrevDecl) {
120      // Try to correct for a typo in the superclass name.
121      LookupResult R(*this, SuperName, SuperLoc, LookupOrdinaryName);
122      if (CorrectTypo(R, TUScope, 0) &&
123          (PrevDecl = R.getAsSingle<ObjCInterfaceDecl>())) {
124        Diag(SuperLoc, diag::err_undef_superclass_suggest)
125          << SuperName << ClassName << PrevDecl->getDeclName();
126        Diag(PrevDecl->getLocation(), diag::note_previous_decl)
127          << PrevDecl->getDeclName();
128      }
129    }
130
131    if (PrevDecl == IDecl) {
132      Diag(SuperLoc, diag::err_recursive_superclass)
133        << SuperName << ClassName << SourceRange(AtInterfaceLoc, ClassLoc);
134      IDecl->setLocEnd(ClassLoc);
135    } else {
136      ObjCInterfaceDecl *SuperClassDecl =
137                                dyn_cast_or_null<ObjCInterfaceDecl>(PrevDecl);
138
139      // Diagnose classes that inherit from deprecated classes.
140      if (SuperClassDecl)
141        (void)DiagnoseUseOfDecl(SuperClassDecl, SuperLoc);
142
143      if (PrevDecl && SuperClassDecl == 0) {
144        // The previous declaration was not a class decl. Check if we have a
145        // typedef. If we do, get the underlying class type.
146        if (const TypedefDecl *TDecl = dyn_cast_or_null<TypedefDecl>(PrevDecl)) {
147          QualType T = TDecl->getUnderlyingType();
148          if (T->isObjCInterfaceType()) {
149            if (NamedDecl *IDecl = T->getAs<ObjCInterfaceType>()->getDecl())
150              SuperClassDecl = dyn_cast<ObjCInterfaceDecl>(IDecl);
151          }
152        }
153
154        // This handles the following case:
155        //
156        // typedef int SuperClass;
157        // @interface MyClass : SuperClass {} @end
158        //
159        if (!SuperClassDecl) {
160          Diag(SuperLoc, diag::err_redefinition_different_kind) << SuperName;
161          Diag(PrevDecl->getLocation(), diag::note_previous_definition);
162        }
163      }
164
165      if (!dyn_cast_or_null<TypedefDecl>(PrevDecl)) {
166        if (!SuperClassDecl)
167          Diag(SuperLoc, diag::err_undef_superclass)
168            << SuperName << ClassName << SourceRange(AtInterfaceLoc, ClassLoc);
169        else if (SuperClassDecl->isForwardDecl())
170          Diag(SuperLoc, diag::err_undef_superclass)
171            << SuperClassDecl->getDeclName() << ClassName
172            << SourceRange(AtInterfaceLoc, ClassLoc);
173      }
174      IDecl->setSuperClass(SuperClassDecl);
175      IDecl->setSuperClassLoc(SuperLoc);
176      IDecl->setLocEnd(SuperLoc);
177    }
178  } else { // we have a root class.
179    IDecl->setLocEnd(ClassLoc);
180  }
181
182  /// Check then save referenced protocols.
183  if (NumProtoRefs) {
184    IDecl->setProtocolList((ObjCProtocolDecl**)ProtoRefs, NumProtoRefs,
185                           ProtoLocs, Context);
186    IDecl->setLocEnd(EndProtoLoc);
187  }
188
189  CheckObjCDeclScope(IDecl);
190  return DeclPtrTy::make(IDecl);
191}
192
193/// ActOnCompatiblityAlias - this action is called after complete parsing of
194/// @compatibility_alias declaration. It sets up the alias relationships.
195Sema::DeclPtrTy Sema::ActOnCompatiblityAlias(SourceLocation AtLoc,
196                                             IdentifierInfo *AliasName,
197                                             SourceLocation AliasLocation,
198                                             IdentifierInfo *ClassName,
199                                             SourceLocation ClassLocation) {
200  // Look for previous declaration of alias name
201  NamedDecl *ADecl = LookupSingleName(TUScope, AliasName, LookupOrdinaryName);
202  if (ADecl) {
203    if (isa<ObjCCompatibleAliasDecl>(ADecl))
204      Diag(AliasLocation, diag::warn_previous_alias_decl);
205    else
206      Diag(AliasLocation, diag::err_conflicting_aliasing_type) << AliasName;
207    Diag(ADecl->getLocation(), diag::note_previous_declaration);
208    return DeclPtrTy();
209  }
210  // Check for class declaration
211  NamedDecl *CDeclU = LookupSingleName(TUScope, ClassName, LookupOrdinaryName);
212  if (const TypedefDecl *TDecl = dyn_cast_or_null<TypedefDecl>(CDeclU)) {
213    QualType T = TDecl->getUnderlyingType();
214    if (T->isObjCInterfaceType()) {
215      if (NamedDecl *IDecl = T->getAs<ObjCInterfaceType>()->getDecl()) {
216        ClassName = IDecl->getIdentifier();
217        CDeclU = LookupSingleName(TUScope, ClassName, LookupOrdinaryName);
218      }
219    }
220  }
221  ObjCInterfaceDecl *CDecl = dyn_cast_or_null<ObjCInterfaceDecl>(CDeclU);
222  if (CDecl == 0) {
223    Diag(ClassLocation, diag::warn_undef_interface) << ClassName;
224    if (CDeclU)
225      Diag(CDeclU->getLocation(), diag::note_previous_declaration);
226    return DeclPtrTy();
227  }
228
229  // Everything checked out, instantiate a new alias declaration AST.
230  ObjCCompatibleAliasDecl *AliasDecl =
231    ObjCCompatibleAliasDecl::Create(Context, CurContext, AtLoc, AliasName, CDecl);
232
233  if (!CheckObjCDeclScope(AliasDecl))
234    PushOnScopeChains(AliasDecl, TUScope);
235
236  return DeclPtrTy::make(AliasDecl);
237}
238
239void Sema::CheckForwardProtocolDeclarationForCircularDependency(
240  IdentifierInfo *PName,
241  SourceLocation &Ploc, SourceLocation PrevLoc,
242  const ObjCList<ObjCProtocolDecl> &PList) {
243  for (ObjCList<ObjCProtocolDecl>::iterator I = PList.begin(),
244       E = PList.end(); I != E; ++I) {
245
246    if (ObjCProtocolDecl *PDecl = LookupProtocol((*I)->getIdentifier())) {
247      if (PDecl->getIdentifier() == PName) {
248        Diag(Ploc, diag::err_protocol_has_circular_dependency);
249        Diag(PrevLoc, diag::note_previous_definition);
250      }
251      CheckForwardProtocolDeclarationForCircularDependency(PName, Ploc,
252        PDecl->getLocation(), PDecl->getReferencedProtocols());
253    }
254  }
255}
256
257Sema::DeclPtrTy
258Sema::ActOnStartProtocolInterface(SourceLocation AtProtoInterfaceLoc,
259                                  IdentifierInfo *ProtocolName,
260                                  SourceLocation ProtocolLoc,
261                                  const DeclPtrTy *ProtoRefs,
262                                  unsigned NumProtoRefs,
263                                  const SourceLocation *ProtoLocs,
264                                  SourceLocation EndProtoLoc,
265                                  AttributeList *AttrList) {
266  // FIXME: Deal with AttrList.
267  assert(ProtocolName && "Missing protocol identifier");
268  ObjCProtocolDecl *PDecl = LookupProtocol(ProtocolName);
269  if (PDecl) {
270    // Protocol already seen. Better be a forward protocol declaration
271    if (!PDecl->isForwardDecl()) {
272      Diag(ProtocolLoc, diag::warn_duplicate_protocol_def) << ProtocolName;
273      Diag(PDecl->getLocation(), diag::note_previous_definition);
274      // Just return the protocol we already had.
275      // FIXME: don't leak the objects passed in!
276      return DeclPtrTy::make(PDecl);
277    }
278    ObjCList<ObjCProtocolDecl> PList;
279    PList.set((ObjCProtocolDecl *const*)ProtoRefs, NumProtoRefs, Context);
280    CheckForwardProtocolDeclarationForCircularDependency(
281      ProtocolName, ProtocolLoc, PDecl->getLocation(), PList);
282    PList.Destroy(Context);
283
284    // Make sure the cached decl gets a valid start location.
285    PDecl->setLocation(AtProtoInterfaceLoc);
286    PDecl->setForwardDecl(false);
287  } else {
288    PDecl = ObjCProtocolDecl::Create(Context, CurContext,
289                                     AtProtoInterfaceLoc,ProtocolName);
290    PushOnScopeChains(PDecl, TUScope);
291    PDecl->setForwardDecl(false);
292  }
293  if (AttrList)
294    ProcessDeclAttributeList(TUScope, PDecl, AttrList);
295  if (NumProtoRefs) {
296    /// Check then save referenced protocols.
297    PDecl->setProtocolList((ObjCProtocolDecl**)ProtoRefs, NumProtoRefs,
298                           ProtoLocs, Context);
299    PDecl->setLocEnd(EndProtoLoc);
300  }
301
302  CheckObjCDeclScope(PDecl);
303  return DeclPtrTy::make(PDecl);
304}
305
306/// FindProtocolDeclaration - This routine looks up protocols and
307/// issues an error if they are not declared. It returns list of
308/// protocol declarations in its 'Protocols' argument.
309void
310Sema::FindProtocolDeclaration(bool WarnOnDeclarations,
311                              const IdentifierLocPair *ProtocolId,
312                              unsigned NumProtocols,
313                              llvm::SmallVectorImpl<DeclPtrTy> &Protocols) {
314  for (unsigned i = 0; i != NumProtocols; ++i) {
315    ObjCProtocolDecl *PDecl = LookupProtocol(ProtocolId[i].first);
316    if (!PDecl) {
317      LookupResult R(*this, ProtocolId[i].first, ProtocolId[i].second,
318                     LookupObjCProtocolName);
319      if (CorrectTypo(R, TUScope, 0) &&
320          (PDecl = R.getAsSingle<ObjCProtocolDecl>())) {
321        Diag(ProtocolId[i].second, diag::err_undeclared_protocol_suggest)
322          << ProtocolId[i].first << R.getLookupName();
323        Diag(PDecl->getLocation(), diag::note_previous_decl)
324          << PDecl->getDeclName();
325      }
326    }
327
328    if (!PDecl) {
329      Diag(ProtocolId[i].second, diag::err_undeclared_protocol)
330        << ProtocolId[i].first;
331      continue;
332    }
333
334    (void)DiagnoseUseOfDecl(PDecl, ProtocolId[i].second);
335
336    // If this is a forward declaration and we are supposed to warn in this
337    // case, do it.
338    if (WarnOnDeclarations && PDecl->isForwardDecl())
339      Diag(ProtocolId[i].second, diag::warn_undef_protocolref)
340        << ProtocolId[i].first;
341    Protocols.push_back(DeclPtrTy::make(PDecl));
342  }
343}
344
345/// DiagnoseClassExtensionDupMethods - Check for duplicate declaration of
346/// a class method in its extension.
347///
348void Sema::DiagnoseClassExtensionDupMethods(ObjCCategoryDecl *CAT,
349                                            ObjCInterfaceDecl *ID) {
350  if (!ID)
351    return;  // Possibly due to previous error
352
353  llvm::DenseMap<Selector, const ObjCMethodDecl*> MethodMap;
354  for (ObjCInterfaceDecl::method_iterator i = ID->meth_begin(),
355       e =  ID->meth_end(); i != e; ++i) {
356    ObjCMethodDecl *MD = *i;
357    MethodMap[MD->getSelector()] = MD;
358  }
359
360  if (MethodMap.empty())
361    return;
362  for (ObjCCategoryDecl::method_iterator i = CAT->meth_begin(),
363       e =  CAT->meth_end(); i != e; ++i) {
364    ObjCMethodDecl *Method = *i;
365    const ObjCMethodDecl *&PrevMethod = MethodMap[Method->getSelector()];
366    if (PrevMethod && !MatchTwoMethodDeclarations(Method, PrevMethod)) {
367      Diag(Method->getLocation(), diag::err_duplicate_method_decl)
368            << Method->getDeclName();
369      Diag(PrevMethod->getLocation(), diag::note_previous_declaration);
370    }
371  }
372}
373
374/// ActOnForwardProtocolDeclaration - Handle @protocol foo;
375Action::DeclPtrTy
376Sema::ActOnForwardProtocolDeclaration(SourceLocation AtProtocolLoc,
377                                      const IdentifierLocPair *IdentList,
378                                      unsigned NumElts,
379                                      AttributeList *attrList) {
380  llvm::SmallVector<ObjCProtocolDecl*, 32> Protocols;
381  llvm::SmallVector<SourceLocation, 8> ProtoLocs;
382
383  for (unsigned i = 0; i != NumElts; ++i) {
384    IdentifierInfo *Ident = IdentList[i].first;
385    ObjCProtocolDecl *PDecl = LookupProtocol(Ident);
386    if (PDecl == 0) { // Not already seen?
387      PDecl = ObjCProtocolDecl::Create(Context, CurContext,
388                                       IdentList[i].second, Ident);
389      PushOnScopeChains(PDecl, TUScope);
390    }
391    if (attrList)
392      ProcessDeclAttributeList(TUScope, PDecl, attrList);
393    Protocols.push_back(PDecl);
394    ProtoLocs.push_back(IdentList[i].second);
395  }
396
397  ObjCForwardProtocolDecl *PDecl =
398    ObjCForwardProtocolDecl::Create(Context, CurContext, AtProtocolLoc,
399                                    Protocols.data(), Protocols.size(),
400                                    ProtoLocs.data());
401  CurContext->addDecl(PDecl);
402  CheckObjCDeclScope(PDecl);
403  return DeclPtrTy::make(PDecl);
404}
405
406Sema::DeclPtrTy Sema::
407ActOnStartCategoryInterface(SourceLocation AtInterfaceLoc,
408                            IdentifierInfo *ClassName, SourceLocation ClassLoc,
409                            IdentifierInfo *CategoryName,
410                            SourceLocation CategoryLoc,
411                            const DeclPtrTy *ProtoRefs,
412                            unsigned NumProtoRefs,
413                            const SourceLocation *ProtoLocs,
414                            SourceLocation EndProtoLoc) {
415  ObjCCategoryDecl *CDecl = 0;
416  ObjCInterfaceDecl *IDecl = getObjCInterfaceDecl(ClassName, ClassLoc);
417
418  /// Check that class of this category is already completely declared.
419  if (!IDecl || IDecl->isForwardDecl()) {
420    // Create an invalid ObjCCategoryDecl to serve as context for
421    // the enclosing method declarations.  We mark the decl invalid
422    // to make it clear that this isn't a valid AST.
423    CDecl = ObjCCategoryDecl::Create(Context, CurContext, AtInterfaceLoc,
424                                     ClassLoc, CategoryLoc, CategoryName);
425    CDecl->setInvalidDecl();
426    Diag(ClassLoc, diag::err_undef_interface) << ClassName;
427    return DeclPtrTy::make(CDecl);
428  }
429
430  if (!CategoryName) {
431    // Class extensions require a special treatment. Use an existing one.
432    // Note that 'getClassExtension()' can return NULL.
433    CDecl = IDecl->getClassExtension();
434  }
435
436  if (!CDecl) {
437    CDecl = ObjCCategoryDecl::Create(Context, CurContext, AtInterfaceLoc,
438                                     ClassLoc, CategoryLoc, CategoryName);
439    // FIXME: PushOnScopeChains?
440    CurContext->addDecl(CDecl);
441
442    CDecl->setClassInterface(IDecl);
443    // Insert first use of class extension to the list of class's categories.
444    if (!CategoryName)
445      CDecl->insertNextClassCategory();
446  }
447
448  // If the interface is deprecated, warn about it.
449  (void)DiagnoseUseOfDecl(IDecl, ClassLoc);
450
451  if (CategoryName) {
452    /// Check for duplicate interface declaration for this category
453    ObjCCategoryDecl *CDeclChain;
454    for (CDeclChain = IDecl->getCategoryList(); CDeclChain;
455         CDeclChain = CDeclChain->getNextClassCategory()) {
456      if (CDeclChain->getIdentifier() == CategoryName) {
457        // Class extensions can be declared multiple times.
458        Diag(CategoryLoc, diag::warn_dup_category_def)
459          << ClassName << CategoryName;
460        Diag(CDeclChain->getLocation(), diag::note_previous_definition);
461        break;
462      }
463    }
464    if (!CDeclChain)
465      CDecl->insertNextClassCategory();
466  }
467
468  if (NumProtoRefs) {
469    CDecl->setProtocolList((ObjCProtocolDecl**)ProtoRefs, NumProtoRefs,
470                           ProtoLocs, Context);
471    // Protocols in the class extension belong to the class.
472    if (CDecl->IsClassExtension())
473     IDecl->mergeClassExtensionProtocolList((ObjCProtocolDecl**)ProtoRefs,
474                                            NumProtoRefs, ProtoLocs,
475                                            Context);
476  }
477
478  CheckObjCDeclScope(CDecl);
479  return DeclPtrTy::make(CDecl);
480}
481
482/// ActOnStartCategoryImplementation - Perform semantic checks on the
483/// category implementation declaration and build an ObjCCategoryImplDecl
484/// object.
485Sema::DeclPtrTy Sema::ActOnStartCategoryImplementation(
486                      SourceLocation AtCatImplLoc,
487                      IdentifierInfo *ClassName, SourceLocation ClassLoc,
488                      IdentifierInfo *CatName, SourceLocation CatLoc) {
489  ObjCInterfaceDecl *IDecl = getObjCInterfaceDecl(ClassName, ClassLoc);
490  ObjCCategoryDecl *CatIDecl = 0;
491  if (IDecl) {
492    CatIDecl = IDecl->FindCategoryDeclaration(CatName);
493    if (!CatIDecl) {
494      // Category @implementation with no corresponding @interface.
495      // Create and install one.
496      CatIDecl = ObjCCategoryDecl::Create(Context, CurContext, SourceLocation(),
497                                          SourceLocation(), SourceLocation(),
498                                          CatName);
499      CatIDecl->setClassInterface(IDecl);
500      CatIDecl->insertNextClassCategory();
501    }
502  }
503
504  ObjCCategoryImplDecl *CDecl =
505    ObjCCategoryImplDecl::Create(Context, CurContext, AtCatImplLoc, CatName,
506                                 IDecl);
507  /// Check that class of this category is already completely declared.
508  if (!IDecl || IDecl->isForwardDecl())
509    Diag(ClassLoc, diag::err_undef_interface) << ClassName;
510
511  // FIXME: PushOnScopeChains?
512  CurContext->addDecl(CDecl);
513
514  /// Check that CatName, category name, is not used in another implementation.
515  if (CatIDecl) {
516    if (CatIDecl->getImplementation()) {
517      Diag(ClassLoc, diag::err_dup_implementation_category) << ClassName
518        << CatName;
519      Diag(CatIDecl->getImplementation()->getLocation(),
520           diag::note_previous_definition);
521    } else
522      CatIDecl->setImplementation(CDecl);
523  }
524
525  CheckObjCDeclScope(CDecl);
526  return DeclPtrTy::make(CDecl);
527}
528
529Sema::DeclPtrTy Sema::ActOnStartClassImplementation(
530                      SourceLocation AtClassImplLoc,
531                      IdentifierInfo *ClassName, SourceLocation ClassLoc,
532                      IdentifierInfo *SuperClassname,
533                      SourceLocation SuperClassLoc) {
534  ObjCInterfaceDecl* IDecl = 0;
535  // Check for another declaration kind with the same name.
536  NamedDecl *PrevDecl
537    = LookupSingleName(TUScope, ClassName, LookupOrdinaryName);
538  if (PrevDecl && !isa<ObjCInterfaceDecl>(PrevDecl)) {
539    Diag(ClassLoc, diag::err_redefinition_different_kind) << ClassName;
540    Diag(PrevDecl->getLocation(), diag::note_previous_definition);
541  } else if ((IDecl = dyn_cast_or_null<ObjCInterfaceDecl>(PrevDecl))) {
542    // If this is a forward declaration of an interface, warn.
543    if (IDecl->isForwardDecl()) {
544      Diag(ClassLoc, diag::warn_undef_interface) << ClassName;
545      IDecl = 0;
546    }
547  } else {
548    // We did not find anything with the name ClassName; try to correct for
549    // typos in the class name.
550    LookupResult R(*this, ClassName, ClassLoc, LookupOrdinaryName);
551    if (CorrectTypo(R, TUScope, 0) &&
552        (IDecl = R.getAsSingle<ObjCInterfaceDecl>())) {
553      // Suggest the (potentially) correct interface name. However, put the
554      // fix-it hint itself in a separate note, since changing the name in
555      // the warning would make the fix-it change semantics.However, don't
556      // provide a code-modification hint or use the typo name for recovery,
557      // because this is just a warning. The program may actually be correct.
558      Diag(ClassLoc, diag::warn_undef_interface_suggest)
559        << ClassName << R.getLookupName();
560      Diag(IDecl->getLocation(), diag::note_previous_decl)
561        << R.getLookupName()
562        << CodeModificationHint::CreateReplacement(ClassLoc,
563                                               R.getLookupName().getAsString());
564      IDecl = 0;
565    } else {
566      Diag(ClassLoc, diag::warn_undef_interface) << ClassName;
567    }
568  }
569
570  // Check that super class name is valid class name
571  ObjCInterfaceDecl* SDecl = 0;
572  if (SuperClassname) {
573    // Check if a different kind of symbol declared in this scope.
574    PrevDecl = LookupSingleName(TUScope, SuperClassname, LookupOrdinaryName);
575    if (PrevDecl && !isa<ObjCInterfaceDecl>(PrevDecl)) {
576      Diag(SuperClassLoc, diag::err_redefinition_different_kind)
577        << SuperClassname;
578      Diag(PrevDecl->getLocation(), diag::note_previous_definition);
579    } else {
580      SDecl = dyn_cast_or_null<ObjCInterfaceDecl>(PrevDecl);
581      if (!SDecl)
582        Diag(SuperClassLoc, diag::err_undef_superclass)
583          << SuperClassname << ClassName;
584      else if (IDecl && IDecl->getSuperClass() != SDecl) {
585        // This implementation and its interface do not have the same
586        // super class.
587        Diag(SuperClassLoc, diag::err_conflicting_super_class)
588          << SDecl->getDeclName();
589        Diag(SDecl->getLocation(), diag::note_previous_definition);
590      }
591    }
592  }
593
594  if (!IDecl) {
595    // Legacy case of @implementation with no corresponding @interface.
596    // Build, chain & install the interface decl into the identifier.
597
598    // FIXME: Do we support attributes on the @implementation? If so we should
599    // copy them over.
600    IDecl = ObjCInterfaceDecl::Create(Context, CurContext, AtClassImplLoc,
601                                      ClassName, ClassLoc, false, true);
602    IDecl->setSuperClass(SDecl);
603    IDecl->setLocEnd(ClassLoc);
604
605    PushOnScopeChains(IDecl, TUScope);
606  } else {
607    // Mark the interface as being completed, even if it was just as
608    //   @class ....;
609    // declaration; the user cannot reopen it.
610    IDecl->setForwardDecl(false);
611  }
612
613  ObjCImplementationDecl* IMPDecl =
614    ObjCImplementationDecl::Create(Context, CurContext, AtClassImplLoc,
615                                   IDecl, SDecl);
616
617  if (CheckObjCDeclScope(IMPDecl))
618    return DeclPtrTy::make(IMPDecl);
619
620  // Check that there is no duplicate implementation of this class.
621  if (IDecl->getImplementation()) {
622    // FIXME: Don't leak everything!
623    Diag(ClassLoc, diag::err_dup_implementation_class) << ClassName;
624    Diag(IDecl->getImplementation()->getLocation(),
625         diag::note_previous_definition);
626  } else { // add it to the list.
627    IDecl->setImplementation(IMPDecl);
628    PushOnScopeChains(IMPDecl, TUScope);
629  }
630  return DeclPtrTy::make(IMPDecl);
631}
632
633void Sema::CheckImplementationIvars(ObjCImplementationDecl *ImpDecl,
634                                    ObjCIvarDecl **ivars, unsigned numIvars,
635                                    SourceLocation RBrace) {
636  assert(ImpDecl && "missing implementation decl");
637  ObjCInterfaceDecl* IDecl = ImpDecl->getClassInterface();
638  if (!IDecl)
639    return;
640  /// Check case of non-existing @interface decl.
641  /// (legacy objective-c @implementation decl without an @interface decl).
642  /// Add implementations's ivar to the synthesize class's ivar list.
643  if (IDecl->isImplicitInterfaceDecl()) {
644    IDecl->setLocEnd(RBrace);
645    // Add ivar's to class's DeclContext.
646    for (unsigned i = 0, e = numIvars; i != e; ++i) {
647      ivars[i]->setLexicalDeclContext(ImpDecl);
648      IDecl->makeDeclVisibleInContext(ivars[i], false);
649      ImpDecl->addDecl(ivars[i]);
650    }
651
652    return;
653  }
654  // If implementation has empty ivar list, just return.
655  if (numIvars == 0)
656    return;
657
658  assert(ivars && "missing @implementation ivars");
659  if (LangOpts.ObjCNonFragileABI2) {
660    if (ImpDecl->getSuperClass())
661      Diag(ImpDecl->getLocation(), diag::warn_on_superclass_use);
662    for (unsigned i = 0; i < numIvars; i++) {
663      ObjCIvarDecl* ImplIvar = ivars[i];
664      if (const ObjCIvarDecl *ClsIvar =
665            IDecl->getIvarDecl(ImplIvar->getIdentifier())) {
666        Diag(ImplIvar->getLocation(), diag::err_duplicate_ivar_declaration);
667        Diag(ClsIvar->getLocation(), diag::note_previous_definition);
668        continue;
669      }
670      // Instance ivar to Implementation's DeclContext.
671      ImplIvar->setLexicalDeclContext(ImpDecl);
672      IDecl->makeDeclVisibleInContext(ImplIvar, false);
673      ImpDecl->addDecl(ImplIvar);
674    }
675    return;
676  }
677  // Check interface's Ivar list against those in the implementation.
678  // names and types must match.
679  //
680  unsigned j = 0;
681  ObjCInterfaceDecl::ivar_iterator
682    IVI = IDecl->ivar_begin(), IVE = IDecl->ivar_end();
683  for (; numIvars > 0 && IVI != IVE; ++IVI) {
684    ObjCIvarDecl* ImplIvar = ivars[j++];
685    ObjCIvarDecl* ClsIvar = *IVI;
686    assert (ImplIvar && "missing implementation ivar");
687    assert (ClsIvar && "missing class ivar");
688
689    // First, make sure the types match.
690    if (Context.getCanonicalType(ImplIvar->getType()) !=
691        Context.getCanonicalType(ClsIvar->getType())) {
692      Diag(ImplIvar->getLocation(), diag::err_conflicting_ivar_type)
693        << ImplIvar->getIdentifier()
694        << ImplIvar->getType() << ClsIvar->getType();
695      Diag(ClsIvar->getLocation(), diag::note_previous_definition);
696    } else if (ImplIvar->isBitField() && ClsIvar->isBitField()) {
697      Expr *ImplBitWidth = ImplIvar->getBitWidth();
698      Expr *ClsBitWidth = ClsIvar->getBitWidth();
699      if (ImplBitWidth->EvaluateAsInt(Context).getZExtValue() !=
700          ClsBitWidth->EvaluateAsInt(Context).getZExtValue()) {
701        Diag(ImplBitWidth->getLocStart(), diag::err_conflicting_ivar_bitwidth)
702          << ImplIvar->getIdentifier();
703        Diag(ClsBitWidth->getLocStart(), diag::note_previous_definition);
704      }
705    }
706    // Make sure the names are identical.
707    if (ImplIvar->getIdentifier() != ClsIvar->getIdentifier()) {
708      Diag(ImplIvar->getLocation(), diag::err_conflicting_ivar_name)
709        << ImplIvar->getIdentifier() << ClsIvar->getIdentifier();
710      Diag(ClsIvar->getLocation(), diag::note_previous_definition);
711    }
712    --numIvars;
713  }
714
715  if (numIvars > 0)
716    Diag(ivars[j]->getLocation(), diag::err_inconsistant_ivar_count);
717  else if (IVI != IVE)
718    Diag((*IVI)->getLocation(), diag::err_inconsistant_ivar_count);
719}
720
721void Sema::WarnUndefinedMethod(SourceLocation ImpLoc, ObjCMethodDecl *method,
722                               bool &IncompleteImpl) {
723  if (!IncompleteImpl) {
724    Diag(ImpLoc, diag::warn_incomplete_impl);
725    IncompleteImpl = true;
726  }
727  Diag(method->getLocation(), diag::note_undef_method_impl)
728    << method->getDeclName();
729}
730
731void Sema::WarnConflictingTypedMethods(ObjCMethodDecl *ImpMethodDecl,
732                                       ObjCMethodDecl *IntfMethodDecl) {
733  if (!Context.typesAreCompatible(IntfMethodDecl->getResultType(),
734                                  ImpMethodDecl->getResultType()) &&
735      !Context.QualifiedIdConformsQualifiedId(IntfMethodDecl->getResultType(),
736                                              ImpMethodDecl->getResultType())) {
737    Diag(ImpMethodDecl->getLocation(), diag::warn_conflicting_ret_types)
738      << ImpMethodDecl->getDeclName() << IntfMethodDecl->getResultType()
739      << ImpMethodDecl->getResultType();
740    Diag(IntfMethodDecl->getLocation(), diag::note_previous_definition);
741  }
742
743  for (ObjCMethodDecl::param_iterator IM = ImpMethodDecl->param_begin(),
744       IF = IntfMethodDecl->param_begin(), EM = ImpMethodDecl->param_end();
745       IM != EM; ++IM, ++IF) {
746    QualType ParmDeclTy = (*IF)->getType().getUnqualifiedType();
747    QualType ParmImpTy = (*IM)->getType().getUnqualifiedType();
748    if (Context.typesAreCompatible(ParmDeclTy, ParmImpTy) ||
749        Context.QualifiedIdConformsQualifiedId(ParmDeclTy, ParmImpTy))
750      continue;
751
752    Diag((*IM)->getLocation(), diag::warn_conflicting_param_types)
753      << ImpMethodDecl->getDeclName() << (*IF)->getType()
754      << (*IM)->getType();
755    Diag((*IF)->getLocation(), diag::note_previous_definition);
756  }
757}
758
759/// FIXME: Type hierarchies in Objective-C can be deep. We could most likely
760/// improve the efficiency of selector lookups and type checking by associating
761/// with each protocol / interface / category the flattened instance tables. If
762/// we used an immutable set to keep the table then it wouldn't add significant
763/// memory cost and it would be handy for lookups.
764
765/// CheckProtocolMethodDefs - This routine checks unimplemented methods
766/// Declared in protocol, and those referenced by it.
767void Sema::CheckProtocolMethodDefs(SourceLocation ImpLoc,
768                                   ObjCProtocolDecl *PDecl,
769                                   bool& IncompleteImpl,
770                                   const llvm::DenseSet<Selector> &InsMap,
771                                   const llvm::DenseSet<Selector> &ClsMap,
772                                   ObjCContainerDecl *CDecl) {
773  ObjCInterfaceDecl *IDecl;
774  if (ObjCCategoryDecl *C = dyn_cast<ObjCCategoryDecl>(CDecl))
775    IDecl = C->getClassInterface();
776  else
777    IDecl = dyn_cast<ObjCInterfaceDecl>(CDecl);
778  assert (IDecl && "CheckProtocolMethodDefs - IDecl is null");
779
780  ObjCInterfaceDecl *Super = IDecl->getSuperClass();
781  ObjCInterfaceDecl *NSIDecl = 0;
782  if (getLangOptions().NeXTRuntime) {
783    // check to see if class implements forwardInvocation method and objects
784    // of this class are derived from 'NSProxy' so that to forward requests
785    // from one object to another.
786    // Under such conditions, which means that every method possible is
787    // implemented in the class, we should not issue "Method definition not
788    // found" warnings.
789    // FIXME: Use a general GetUnarySelector method for this.
790    IdentifierInfo* II = &Context.Idents.get("forwardInvocation");
791    Selector fISelector = Context.Selectors.getSelector(1, &II);
792    if (InsMap.count(fISelector))
793      // Is IDecl derived from 'NSProxy'? If so, no instance methods
794      // need be implemented in the implementation.
795      NSIDecl = IDecl->lookupInheritedClass(&Context.Idents.get("NSProxy"));
796  }
797
798  // If a method lookup fails locally we still need to look and see if
799  // the method was implemented by a base class or an inherited
800  // protocol. This lookup is slow, but occurs rarely in correct code
801  // and otherwise would terminate in a warning.
802
803  // check unimplemented instance methods.
804  if (!NSIDecl)
805    for (ObjCProtocolDecl::instmeth_iterator I = PDecl->instmeth_begin(),
806         E = PDecl->instmeth_end(); I != E; ++I) {
807      ObjCMethodDecl *method = *I;
808      if (method->getImplementationControl() != ObjCMethodDecl::Optional &&
809          !method->isSynthesized() && !InsMap.count(method->getSelector()) &&
810          (!Super ||
811           !Super->lookupInstanceMethod(method->getSelector()))) {
812            // Ugly, but necessary. Method declared in protcol might have
813            // have been synthesized due to a property declared in the class which
814            // uses the protocol.
815            ObjCMethodDecl *MethodInClass =
816            IDecl->lookupInstanceMethod(method->getSelector());
817            if (!MethodInClass || !MethodInClass->isSynthesized()) {
818              WarnUndefinedMethod(ImpLoc, method, IncompleteImpl);
819              Diag(CDecl->getLocation(), diag::note_required_for_protocol_at) <<
820                PDecl->getDeclName();
821            }
822          }
823    }
824  // check unimplemented class methods
825  for (ObjCProtocolDecl::classmeth_iterator
826         I = PDecl->classmeth_begin(), E = PDecl->classmeth_end();
827       I != E; ++I) {
828    ObjCMethodDecl *method = *I;
829    if (method->getImplementationControl() != ObjCMethodDecl::Optional &&
830        !ClsMap.count(method->getSelector()) &&
831        (!Super || !Super->lookupClassMethod(method->getSelector()))) {
832      WarnUndefinedMethod(ImpLoc, method, IncompleteImpl);
833      Diag(IDecl->getLocation(), diag::note_required_for_protocol_at) <<
834        PDecl->getDeclName();
835    }
836  }
837  // Check on this protocols's referenced protocols, recursively.
838  for (ObjCProtocolDecl::protocol_iterator PI = PDecl->protocol_begin(),
839       E = PDecl->protocol_end(); PI != E; ++PI)
840    CheckProtocolMethodDefs(ImpLoc, *PI, IncompleteImpl, InsMap, ClsMap, IDecl);
841}
842
843/// MatchAllMethodDeclarations - Check methods declaraed in interface or
844/// or protocol against those declared in their implementations.
845///
846void Sema::MatchAllMethodDeclarations(const llvm::DenseSet<Selector> &InsMap,
847                                      const llvm::DenseSet<Selector> &ClsMap,
848                                      llvm::DenseSet<Selector> &InsMapSeen,
849                                      llvm::DenseSet<Selector> &ClsMapSeen,
850                                      ObjCImplDecl* IMPDecl,
851                                      ObjCContainerDecl* CDecl,
852                                      bool &IncompleteImpl,
853                                      bool ImmediateClass) {
854  // Check and see if instance methods in class interface have been
855  // implemented in the implementation class. If so, their types match.
856  for (ObjCInterfaceDecl::instmeth_iterator I = CDecl->instmeth_begin(),
857       E = CDecl->instmeth_end(); I != E; ++I) {
858    if (InsMapSeen.count((*I)->getSelector()))
859        continue;
860    InsMapSeen.insert((*I)->getSelector());
861    if (!(*I)->isSynthesized() &&
862        !InsMap.count((*I)->getSelector())) {
863      if (ImmediateClass)
864        WarnUndefinedMethod(IMPDecl->getLocation(), *I, IncompleteImpl);
865      continue;
866    } else {
867      ObjCMethodDecl *ImpMethodDecl =
868      IMPDecl->getInstanceMethod((*I)->getSelector());
869      ObjCMethodDecl *IntfMethodDecl =
870      CDecl->getInstanceMethod((*I)->getSelector());
871      assert(IntfMethodDecl &&
872             "IntfMethodDecl is null in ImplMethodsVsClassMethods");
873      // ImpMethodDecl may be null as in a @dynamic property.
874      if (ImpMethodDecl)
875        WarnConflictingTypedMethods(ImpMethodDecl, IntfMethodDecl);
876    }
877  }
878
879  // Check and see if class methods in class interface have been
880  // implemented in the implementation class. If so, their types match.
881   for (ObjCInterfaceDecl::classmeth_iterator
882       I = CDecl->classmeth_begin(), E = CDecl->classmeth_end(); I != E; ++I) {
883     if (ClsMapSeen.count((*I)->getSelector()))
884       continue;
885     ClsMapSeen.insert((*I)->getSelector());
886    if (!ClsMap.count((*I)->getSelector())) {
887      if (ImmediateClass)
888        WarnUndefinedMethod(IMPDecl->getLocation(), *I, IncompleteImpl);
889    } else {
890      ObjCMethodDecl *ImpMethodDecl =
891        IMPDecl->getClassMethod((*I)->getSelector());
892      ObjCMethodDecl *IntfMethodDecl =
893        CDecl->getClassMethod((*I)->getSelector());
894      WarnConflictingTypedMethods(ImpMethodDecl, IntfMethodDecl);
895    }
896  }
897  if (ObjCInterfaceDecl *I = dyn_cast<ObjCInterfaceDecl> (CDecl)) {
898    // Check for any implementation of a methods declared in protocol.
899    for (ObjCInterfaceDecl::protocol_iterator PI = I->protocol_begin(),
900         E = I->protocol_end(); PI != E; ++PI)
901      MatchAllMethodDeclarations(InsMap, ClsMap, InsMapSeen, ClsMapSeen,
902                                 IMPDecl,
903                                 (*PI), IncompleteImpl, false);
904    if (I->getSuperClass())
905      MatchAllMethodDeclarations(InsMap, ClsMap, InsMapSeen, ClsMapSeen,
906                                 IMPDecl,
907                                 I->getSuperClass(), IncompleteImpl, false);
908  }
909}
910
911void Sema::ImplMethodsVsClassMethods(ObjCImplDecl* IMPDecl,
912                                     ObjCContainerDecl* CDecl,
913                                     bool IncompleteImpl) {
914  llvm::DenseSet<Selector> InsMap;
915  // Check and see if instance methods in class interface have been
916  // implemented in the implementation class.
917  for (ObjCImplementationDecl::instmeth_iterator
918         I = IMPDecl->instmeth_begin(), E = IMPDecl->instmeth_end(); I!=E; ++I)
919    InsMap.insert((*I)->getSelector());
920
921  // Check and see if properties declared in the interface have either 1)
922  // an implementation or 2) there is a @synthesize/@dynamic implementation
923  // of the property in the @implementation.
924  if (isa<ObjCInterfaceDecl>(CDecl))
925    DiagnoseUnimplementedProperties(IMPDecl, CDecl, InsMap);
926
927  llvm::DenseSet<Selector> ClsMap;
928  for (ObjCImplementationDecl::classmeth_iterator
929       I = IMPDecl->classmeth_begin(),
930       E = IMPDecl->classmeth_end(); I != E; ++I)
931    ClsMap.insert((*I)->getSelector());
932
933  // Check for type conflict of methods declared in a class/protocol and
934  // its implementation; if any.
935  llvm::DenseSet<Selector> InsMapSeen, ClsMapSeen;
936  MatchAllMethodDeclarations(InsMap, ClsMap, InsMapSeen, ClsMapSeen,
937                             IMPDecl, CDecl,
938                             IncompleteImpl, true);
939
940  // Check the protocol list for unimplemented methods in the @implementation
941  // class.
942  // Check and see if class methods in class interface have been
943  // implemented in the implementation class.
944
945  if (ObjCInterfaceDecl *I = dyn_cast<ObjCInterfaceDecl> (CDecl)) {
946    for (ObjCInterfaceDecl::protocol_iterator PI = I->protocol_begin(),
947         E = I->protocol_end(); PI != E; ++PI)
948      CheckProtocolMethodDefs(IMPDecl->getLocation(), *PI, IncompleteImpl,
949                              InsMap, ClsMap, I);
950    // Check class extensions (unnamed categories)
951    for (ObjCCategoryDecl *Categories = I->getCategoryList();
952         Categories; Categories = Categories->getNextClassCategory()) {
953      if (Categories->IsClassExtension()) {
954        ImplMethodsVsClassMethods(IMPDecl, Categories, IncompleteImpl);
955        break;
956      }
957    }
958  } else if (ObjCCategoryDecl *C = dyn_cast<ObjCCategoryDecl>(CDecl)) {
959    // For extended class, unimplemented methods in its protocols will
960    // be reported in the primary class.
961    if (!C->IsClassExtension()) {
962      for (ObjCCategoryDecl::protocol_iterator PI = C->protocol_begin(),
963           E = C->protocol_end(); PI != E; ++PI)
964        CheckProtocolMethodDefs(IMPDecl->getLocation(), *PI, IncompleteImpl,
965                                InsMap, ClsMap, CDecl);
966      // Report unimplemented properties in the category as well.
967      // When reporting on missing setter/getters, do not report when
968      // setter/getter is implemented in category's primary class
969      // implementation.
970      if (ObjCInterfaceDecl *ID = C->getClassInterface())
971        if (ObjCImplDecl *IMP = ID->getImplementation()) {
972          for (ObjCImplementationDecl::instmeth_iterator
973               I = IMP->instmeth_begin(), E = IMP->instmeth_end(); I!=E; ++I)
974            InsMap.insert((*I)->getSelector());
975        }
976      DiagnoseUnimplementedProperties(IMPDecl, CDecl, InsMap);
977    }
978  } else
979    assert(false && "invalid ObjCContainerDecl type.");
980}
981
982/// ActOnForwardClassDeclaration -
983Action::DeclPtrTy
984Sema::ActOnForwardClassDeclaration(SourceLocation AtClassLoc,
985                                   IdentifierInfo **IdentList,
986                                   SourceLocation *IdentLocs,
987                                   unsigned NumElts) {
988  llvm::SmallVector<ObjCInterfaceDecl*, 32> Interfaces;
989
990  for (unsigned i = 0; i != NumElts; ++i) {
991    // Check for another declaration kind with the same name.
992    NamedDecl *PrevDecl
993      = LookupSingleName(TUScope, IdentList[i], LookupOrdinaryName);
994    if (PrevDecl && PrevDecl->isTemplateParameter()) {
995      // Maybe we will complain about the shadowed template parameter.
996      DiagnoseTemplateParameterShadow(AtClassLoc, PrevDecl);
997      // Just pretend that we didn't see the previous declaration.
998      PrevDecl = 0;
999    }
1000
1001    if (PrevDecl && !isa<ObjCInterfaceDecl>(PrevDecl)) {
1002      // GCC apparently allows the following idiom:
1003      //
1004      // typedef NSObject < XCElementTogglerP > XCElementToggler;
1005      // @class XCElementToggler;
1006      //
1007      // FIXME: Make an extension?
1008      TypedefDecl *TDD = dyn_cast<TypedefDecl>(PrevDecl);
1009      if (!TDD || !isa<ObjCInterfaceType>(TDD->getUnderlyingType())) {
1010        Diag(AtClassLoc, diag::err_redefinition_different_kind) << IdentList[i];
1011        Diag(PrevDecl->getLocation(), diag::note_previous_definition);
1012      } else if (TDD) {
1013        // a forward class declaration matching a typedef name of a class refers
1014        // to the underlying class.
1015        if (ObjCInterfaceType * OI =
1016              dyn_cast<ObjCInterfaceType>(TDD->getUnderlyingType()))
1017          PrevDecl = OI->getDecl();
1018      }
1019    }
1020    ObjCInterfaceDecl *IDecl = dyn_cast_or_null<ObjCInterfaceDecl>(PrevDecl);
1021    if (!IDecl) {  // Not already seen?  Make a forward decl.
1022      IDecl = ObjCInterfaceDecl::Create(Context, CurContext, AtClassLoc,
1023                                        IdentList[i], IdentLocs[i], true);
1024
1025      // Push the ObjCInterfaceDecl on the scope chain but do *not* add it to
1026      // the current DeclContext.  This prevents clients that walk DeclContext
1027      // from seeing the imaginary ObjCInterfaceDecl until it is actually
1028      // declared later (if at all).  We also take care to explicitly make
1029      // sure this declaration is visible for name lookup.
1030      PushOnScopeChains(IDecl, TUScope, false);
1031      CurContext->makeDeclVisibleInContext(IDecl, true);
1032    }
1033
1034    Interfaces.push_back(IDecl);
1035  }
1036
1037  assert(Interfaces.size() == NumElts);
1038  ObjCClassDecl *CDecl = ObjCClassDecl::Create(Context, CurContext, AtClassLoc,
1039                                               Interfaces.data(), IdentLocs,
1040                                               Interfaces.size());
1041  CurContext->addDecl(CDecl);
1042  CheckObjCDeclScope(CDecl);
1043  return DeclPtrTy::make(CDecl);
1044}
1045
1046
1047/// MatchTwoMethodDeclarations - Checks that two methods have matching type and
1048/// returns true, or false, accordingly.
1049/// TODO: Handle protocol list; such as id<p1,p2> in type comparisons
1050bool Sema::MatchTwoMethodDeclarations(const ObjCMethodDecl *Method,
1051                                      const ObjCMethodDecl *PrevMethod,
1052                                      bool matchBasedOnSizeAndAlignment) {
1053  QualType T1 = Context.getCanonicalType(Method->getResultType());
1054  QualType T2 = Context.getCanonicalType(PrevMethod->getResultType());
1055
1056  if (T1 != T2) {
1057    // The result types are different.
1058    if (!matchBasedOnSizeAndAlignment)
1059      return false;
1060    // Incomplete types don't have a size and alignment.
1061    if (T1->isIncompleteType() || T2->isIncompleteType())
1062      return false;
1063    // Check is based on size and alignment.
1064    if (Context.getTypeInfo(T1) != Context.getTypeInfo(T2))
1065      return false;
1066  }
1067
1068  ObjCMethodDecl::param_iterator ParamI = Method->param_begin(),
1069       E = Method->param_end();
1070  ObjCMethodDecl::param_iterator PrevI = PrevMethod->param_begin();
1071
1072  for (; ParamI != E; ++ParamI, ++PrevI) {
1073    assert(PrevI != PrevMethod->param_end() && "Param mismatch");
1074    T1 = Context.getCanonicalType((*ParamI)->getType());
1075    T2 = Context.getCanonicalType((*PrevI)->getType());
1076    if (T1 != T2) {
1077      // The result types are different.
1078      if (!matchBasedOnSizeAndAlignment)
1079        return false;
1080      // Incomplete types don't have a size and alignment.
1081      if (T1->isIncompleteType() || T2->isIncompleteType())
1082        return false;
1083      // Check is based on size and alignment.
1084      if (Context.getTypeInfo(T1) != Context.getTypeInfo(T2))
1085        return false;
1086    }
1087  }
1088  return true;
1089}
1090
1091/// \brief Read the contents of the instance and factory method pools
1092/// for a given selector from external storage.
1093///
1094/// This routine should only be called once, when neither the instance
1095/// nor the factory method pool has an entry for this selector.
1096Sema::MethodPool::iterator Sema::ReadMethodPool(Selector Sel,
1097                                                bool isInstance) {
1098  assert(ExternalSource && "We need an external AST source");
1099  assert(InstanceMethodPool.find(Sel) == InstanceMethodPool.end() &&
1100         "Selector data already loaded into the instance method pool");
1101  assert(FactoryMethodPool.find(Sel) == FactoryMethodPool.end() &&
1102         "Selector data already loaded into the factory method pool");
1103
1104  // Read the method list from the external source.
1105  std::pair<ObjCMethodList, ObjCMethodList> Methods
1106    = ExternalSource->ReadMethodPool(Sel);
1107
1108  if (isInstance) {
1109    if (Methods.second.Method)
1110      FactoryMethodPool[Sel] = Methods.second;
1111    return InstanceMethodPool.insert(std::make_pair(Sel, Methods.first)).first;
1112  }
1113
1114  if (Methods.first.Method)
1115    InstanceMethodPool[Sel] = Methods.first;
1116
1117  return FactoryMethodPool.insert(std::make_pair(Sel, Methods.second)).first;
1118}
1119
1120void Sema::AddInstanceMethodToGlobalPool(ObjCMethodDecl *Method) {
1121  llvm::DenseMap<Selector, ObjCMethodList>::iterator Pos
1122    = InstanceMethodPool.find(Method->getSelector());
1123  if (Pos == InstanceMethodPool.end()) {
1124    if (ExternalSource && !FactoryMethodPool.count(Method->getSelector()))
1125      Pos = ReadMethodPool(Method->getSelector(), /*isInstance=*/true);
1126    else
1127      Pos = InstanceMethodPool.insert(std::make_pair(Method->getSelector(),
1128                                                     ObjCMethodList())).first;
1129  }
1130
1131  ObjCMethodList &Entry = Pos->second;
1132  if (Entry.Method == 0) {
1133    // Haven't seen a method with this selector name yet - add it.
1134    Entry.Method = Method;
1135    Entry.Next = 0;
1136    return;
1137  }
1138
1139  // We've seen a method with this name, see if we have already seen this type
1140  // signature.
1141  for (ObjCMethodList *List = &Entry; List; List = List->Next)
1142    if (MatchTwoMethodDeclarations(Method, List->Method))
1143      return;
1144
1145  // We have a new signature for an existing method - add it.
1146  // This is extremely rare. Only 1% of Cocoa selectors are "overloaded".
1147  ObjCMethodList *Mem = BumpAlloc.Allocate<ObjCMethodList>();
1148  Entry.Next = new (Mem) ObjCMethodList(Method, Entry.Next);
1149}
1150
1151// FIXME: Finish implementing -Wno-strict-selector-match.
1152ObjCMethodDecl *Sema::LookupInstanceMethodInGlobalPool(Selector Sel,
1153                                                       SourceRange R,
1154                                                       bool warn) {
1155  llvm::DenseMap<Selector, ObjCMethodList>::iterator Pos
1156    = InstanceMethodPool.find(Sel);
1157  if (Pos == InstanceMethodPool.end()) {
1158    if (ExternalSource && !FactoryMethodPool.count(Sel))
1159      Pos = ReadMethodPool(Sel, /*isInstance=*/true);
1160    else
1161      return 0;
1162  }
1163
1164  ObjCMethodList &MethList = Pos->second;
1165  bool issueWarning = false;
1166
1167  if (MethList.Method && MethList.Next) {
1168    for (ObjCMethodList *Next = MethList.Next; Next; Next = Next->Next)
1169      // This checks if the methods differ by size & alignment.
1170      if (!MatchTwoMethodDeclarations(MethList.Method, Next->Method, true))
1171        issueWarning = warn;
1172  }
1173  if (issueWarning && (MethList.Method && MethList.Next)) {
1174    Diag(R.getBegin(), diag::warn_multiple_method_decl) << Sel << R;
1175    Diag(MethList.Method->getLocStart(), diag::note_using)
1176      << MethList.Method->getSourceRange();
1177    for (ObjCMethodList *Next = MethList.Next; Next; Next = Next->Next)
1178      Diag(Next->Method->getLocStart(), diag::note_also_found)
1179        << Next->Method->getSourceRange();
1180  }
1181  return MethList.Method;
1182}
1183
1184void Sema::AddFactoryMethodToGlobalPool(ObjCMethodDecl *Method) {
1185  llvm::DenseMap<Selector, ObjCMethodList>::iterator Pos
1186    = FactoryMethodPool.find(Method->getSelector());
1187  if (Pos == FactoryMethodPool.end()) {
1188    if (ExternalSource && !InstanceMethodPool.count(Method->getSelector()))
1189      Pos = ReadMethodPool(Method->getSelector(), /*isInstance=*/false);
1190    else
1191      Pos = FactoryMethodPool.insert(std::make_pair(Method->getSelector(),
1192                                                    ObjCMethodList())).first;
1193  }
1194
1195  ObjCMethodList &FirstMethod = Pos->second;
1196  if (!FirstMethod.Method) {
1197    // Haven't seen a method with this selector name yet - add it.
1198    FirstMethod.Method = Method;
1199    FirstMethod.Next = 0;
1200  } else {
1201    // We've seen a method with this name, now check the type signature(s).
1202    bool match = MatchTwoMethodDeclarations(Method, FirstMethod.Method);
1203
1204    for (ObjCMethodList *Next = FirstMethod.Next; !match && Next;
1205         Next = Next->Next)
1206      match = MatchTwoMethodDeclarations(Method, Next->Method);
1207
1208    if (!match) {
1209      // We have a new signature for an existing method - add it.
1210      // This is extremely rare. Only 1% of Cocoa selectors are "overloaded".
1211      ObjCMethodList *Mem = BumpAlloc.Allocate<ObjCMethodList>();
1212      ObjCMethodList *OMI = new (Mem) ObjCMethodList(Method, FirstMethod.Next);
1213      FirstMethod.Next = OMI;
1214    }
1215  }
1216}
1217
1218ObjCMethodDecl *Sema::LookupFactoryMethodInGlobalPool(Selector Sel,
1219                                                      SourceRange R) {
1220  llvm::DenseMap<Selector, ObjCMethodList>::iterator Pos
1221    = FactoryMethodPool.find(Sel);
1222  if (Pos == FactoryMethodPool.end()) {
1223    if (ExternalSource && !InstanceMethodPool.count(Sel))
1224      Pos = ReadMethodPool(Sel, /*isInstance=*/false);
1225    else
1226      return 0;
1227  }
1228
1229  ObjCMethodList &MethList = Pos->second;
1230  bool issueWarning = false;
1231
1232  if (MethList.Method && MethList.Next) {
1233    for (ObjCMethodList *Next = MethList.Next; Next; Next = Next->Next)
1234      // This checks if the methods differ by size & alignment.
1235      if (!MatchTwoMethodDeclarations(MethList.Method, Next->Method, true))
1236        issueWarning = true;
1237  }
1238  if (issueWarning && (MethList.Method && MethList.Next)) {
1239    Diag(R.getBegin(), diag::warn_multiple_method_decl) << Sel << R;
1240    Diag(MethList.Method->getLocStart(), diag::note_using)
1241      << MethList.Method->getSourceRange();
1242    for (ObjCMethodList *Next = MethList.Next; Next; Next = Next->Next)
1243      Diag(Next->Method->getLocStart(), diag::note_also_found)
1244        << Next->Method->getSourceRange();
1245  }
1246  return MethList.Method;
1247}
1248
1249/// CompareMethodParamsInBaseAndSuper - This routine compares methods with
1250/// identical selector names in current and its super classes and issues
1251/// a warning if any of their argument types are incompatible.
1252void Sema::CompareMethodParamsInBaseAndSuper(Decl *ClassDecl,
1253                                             ObjCMethodDecl *Method,
1254                                             bool IsInstance)  {
1255  ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(ClassDecl);
1256  if (ID == 0) return;
1257
1258  while (ObjCInterfaceDecl *SD = ID->getSuperClass()) {
1259    ObjCMethodDecl *SuperMethodDecl =
1260        SD->lookupMethod(Method->getSelector(), IsInstance);
1261    if (SuperMethodDecl == 0) {
1262      ID = SD;
1263      continue;
1264    }
1265    ObjCMethodDecl::param_iterator ParamI = Method->param_begin(),
1266      E = Method->param_end();
1267    ObjCMethodDecl::param_iterator PrevI = SuperMethodDecl->param_begin();
1268    for (; ParamI != E; ++ParamI, ++PrevI) {
1269      // Number of parameters are the same and is guaranteed by selector match.
1270      assert(PrevI != SuperMethodDecl->param_end() && "Param mismatch");
1271      QualType T1 = Context.getCanonicalType((*ParamI)->getType());
1272      QualType T2 = Context.getCanonicalType((*PrevI)->getType());
1273      // If type of arguement of method in this class does not match its
1274      // respective argument type in the super class method, issue warning;
1275      if (!Context.typesAreCompatible(T1, T2)) {
1276        Diag((*ParamI)->getLocation(), diag::ext_typecheck_base_super)
1277          << T1 << T2;
1278        Diag(SuperMethodDecl->getLocation(), diag::note_previous_declaration);
1279        return;
1280      }
1281    }
1282    ID = SD;
1283  }
1284}
1285
1286/// DiagnoseDuplicateIvars -
1287/// Check for duplicate ivars in the entire class at the start of
1288/// @implementation. This becomes necesssary because class extension can
1289/// add ivars to a class in random order which will not be known until
1290/// class's @implementation is seen.
1291void Sema::DiagnoseDuplicateIvars(ObjCInterfaceDecl *ID,
1292                                  ObjCInterfaceDecl *SID) {
1293  for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(),
1294       IVE = ID->ivar_end(); IVI != IVE; ++IVI) {
1295    ObjCIvarDecl* Ivar = (*IVI);
1296    if (Ivar->isInvalidDecl())
1297      continue;
1298    if (IdentifierInfo *II = Ivar->getIdentifier()) {
1299      ObjCIvarDecl* prevIvar = SID->lookupInstanceVariable(II);
1300      if (prevIvar) {
1301        Diag(Ivar->getLocation(), diag::err_duplicate_member) << II;
1302        Diag(prevIvar->getLocation(), diag::note_previous_declaration);
1303        Ivar->setInvalidDecl();
1304      }
1305    }
1306  }
1307}
1308
1309// Note: For class/category implemenations, allMethods/allProperties is
1310// always null.
1311void Sema::ActOnAtEnd(SourceRange AtEnd,
1312                      DeclPtrTy classDecl,
1313                      DeclPtrTy *allMethods, unsigned allNum,
1314                      DeclPtrTy *allProperties, unsigned pNum,
1315                      DeclGroupPtrTy *allTUVars, unsigned tuvNum) {
1316  Decl *ClassDecl = classDecl.getAs<Decl>();
1317
1318  // FIXME: If we don't have a ClassDecl, we have an error. We should consider
1319  // always passing in a decl. If the decl has an error, isInvalidDecl()
1320  // should be true.
1321  if (!ClassDecl)
1322    return;
1323
1324  bool isInterfaceDeclKind =
1325        isa<ObjCInterfaceDecl>(ClassDecl) || isa<ObjCCategoryDecl>(ClassDecl)
1326         || isa<ObjCProtocolDecl>(ClassDecl);
1327  bool checkIdenticalMethods = isa<ObjCImplementationDecl>(ClassDecl);
1328
1329  if (!isInterfaceDeclKind && AtEnd.isInvalid()) {
1330    // FIXME: This is wrong.  We shouldn't be pretending that there is
1331    //  an '@end' in the declaration.
1332    SourceLocation L = ClassDecl->getLocation();
1333    AtEnd.setBegin(L);
1334    AtEnd.setEnd(L);
1335    Diag(L, diag::warn_missing_atend);
1336  }
1337
1338  DeclContext *DC = dyn_cast<DeclContext>(ClassDecl);
1339
1340  // FIXME: Remove these and use the ObjCContainerDecl/DeclContext.
1341  llvm::DenseMap<Selector, const ObjCMethodDecl*> InsMap;
1342  llvm::DenseMap<Selector, const ObjCMethodDecl*> ClsMap;
1343
1344  for (unsigned i = 0; i < allNum; i++ ) {
1345    ObjCMethodDecl *Method =
1346      cast_or_null<ObjCMethodDecl>(allMethods[i].getAs<Decl>());
1347
1348    if (!Method) continue;  // Already issued a diagnostic.
1349    if (Method->isInstanceMethod()) {
1350      /// Check for instance method of the same name with incompatible types
1351      const ObjCMethodDecl *&PrevMethod = InsMap[Method->getSelector()];
1352      bool match = PrevMethod ? MatchTwoMethodDeclarations(Method, PrevMethod)
1353                              : false;
1354      if ((isInterfaceDeclKind && PrevMethod && !match)
1355          || (checkIdenticalMethods && match)) {
1356          Diag(Method->getLocation(), diag::err_duplicate_method_decl)
1357            << Method->getDeclName();
1358          Diag(PrevMethod->getLocation(), diag::note_previous_declaration);
1359      } else {
1360        DC->addDecl(Method);
1361        InsMap[Method->getSelector()] = Method;
1362        /// The following allows us to typecheck messages to "id".
1363        AddInstanceMethodToGlobalPool(Method);
1364        // verify that the instance method conforms to the same definition of
1365        // parent methods if it shadows one.
1366        CompareMethodParamsInBaseAndSuper(ClassDecl, Method, true);
1367      }
1368    } else {
1369      /// Check for class method of the same name with incompatible types
1370      const ObjCMethodDecl *&PrevMethod = ClsMap[Method->getSelector()];
1371      bool match = PrevMethod ? MatchTwoMethodDeclarations(Method, PrevMethod)
1372                              : false;
1373      if ((isInterfaceDeclKind && PrevMethod && !match)
1374          || (checkIdenticalMethods && match)) {
1375        Diag(Method->getLocation(), diag::err_duplicate_method_decl)
1376          << Method->getDeclName();
1377        Diag(PrevMethod->getLocation(), diag::note_previous_declaration);
1378      } else {
1379        DC->addDecl(Method);
1380        ClsMap[Method->getSelector()] = Method;
1381        /// The following allows us to typecheck messages to "Class".
1382        AddFactoryMethodToGlobalPool(Method);
1383        // verify that the class method conforms to the same definition of
1384        // parent methods if it shadows one.
1385        CompareMethodParamsInBaseAndSuper(ClassDecl, Method, false);
1386      }
1387    }
1388  }
1389  if (ObjCInterfaceDecl *I = dyn_cast<ObjCInterfaceDecl>(ClassDecl)) {
1390    // Compares properties declared in this class to those of its
1391    // super class.
1392    ComparePropertiesInBaseAndSuper(I);
1393    CompareProperties(I, DeclPtrTy::make(I));
1394  } else if (ObjCCategoryDecl *C = dyn_cast<ObjCCategoryDecl>(ClassDecl)) {
1395    // Categories are used to extend the class by declaring new methods.
1396    // By the same token, they are also used to add new properties. No
1397    // need to compare the added property to those in the class.
1398
1399    // Compare protocol properties with those in category
1400    CompareProperties(C, DeclPtrTy::make(C));
1401    if (C->IsClassExtension())
1402      DiagnoseClassExtensionDupMethods(C, C->getClassInterface());
1403  }
1404  if (ObjCContainerDecl *CDecl = dyn_cast<ObjCContainerDecl>(ClassDecl)) {
1405    if (CDecl->getIdentifier())
1406      // ProcessPropertyDecl is responsible for diagnosing conflicts with any
1407      // user-defined setter/getter. It also synthesizes setter/getter methods
1408      // and adds them to the DeclContext and global method pools.
1409      for (ObjCContainerDecl::prop_iterator I = CDecl->prop_begin(),
1410                                            E = CDecl->prop_end();
1411           I != E; ++I)
1412        ProcessPropertyDecl(*I, CDecl);
1413    CDecl->setAtEndRange(AtEnd);
1414  }
1415  if (ObjCImplementationDecl *IC=dyn_cast<ObjCImplementationDecl>(ClassDecl)) {
1416    IC->setAtEndRange(AtEnd);
1417    if (ObjCInterfaceDecl* IDecl = IC->getClassInterface()) {
1418      ImplMethodsVsClassMethods(IC, IDecl);
1419      AtomicPropertySetterGetterRules(IC, IDecl);
1420      if (LangOpts.ObjCNonFragileABI2)
1421        while (IDecl->getSuperClass()) {
1422          DiagnoseDuplicateIvars(IDecl, IDecl->getSuperClass());
1423          IDecl = IDecl->getSuperClass();
1424        }
1425    }
1426  } else if (ObjCCategoryImplDecl* CatImplClass =
1427                                   dyn_cast<ObjCCategoryImplDecl>(ClassDecl)) {
1428    CatImplClass->setAtEndRange(AtEnd);
1429
1430    // Find category interface decl and then check that all methods declared
1431    // in this interface are implemented in the category @implementation.
1432    if (ObjCInterfaceDecl* IDecl = CatImplClass->getClassInterface()) {
1433      for (ObjCCategoryDecl *Categories = IDecl->getCategoryList();
1434           Categories; Categories = Categories->getNextClassCategory()) {
1435        if (Categories->getIdentifier() == CatImplClass->getIdentifier()) {
1436          ImplMethodsVsClassMethods(CatImplClass, Categories);
1437          break;
1438        }
1439      }
1440    }
1441  }
1442  if (isInterfaceDeclKind) {
1443    // Reject invalid vardecls.
1444    for (unsigned i = 0; i != tuvNum; i++) {
1445      DeclGroupRef DG = allTUVars[i].getAsVal<DeclGroupRef>();
1446      for (DeclGroupRef::iterator I = DG.begin(), E = DG.end(); I != E; ++I)
1447        if (VarDecl *VDecl = dyn_cast<VarDecl>(*I)) {
1448          if (!VDecl->hasExternalStorage())
1449            Diag(VDecl->getLocation(), diag::err_objc_var_decl_inclass);
1450        }
1451    }
1452  }
1453}
1454
1455
1456/// CvtQTToAstBitMask - utility routine to produce an AST bitmask for
1457/// objective-c's type qualifier from the parser version of the same info.
1458static Decl::ObjCDeclQualifier
1459CvtQTToAstBitMask(ObjCDeclSpec::ObjCDeclQualifier PQTVal) {
1460  Decl::ObjCDeclQualifier ret = Decl::OBJC_TQ_None;
1461  if (PQTVal & ObjCDeclSpec::DQ_In)
1462    ret = (Decl::ObjCDeclQualifier)(ret | Decl::OBJC_TQ_In);
1463  if (PQTVal & ObjCDeclSpec::DQ_Inout)
1464    ret = (Decl::ObjCDeclQualifier)(ret | Decl::OBJC_TQ_Inout);
1465  if (PQTVal & ObjCDeclSpec::DQ_Out)
1466    ret = (Decl::ObjCDeclQualifier)(ret | Decl::OBJC_TQ_Out);
1467  if (PQTVal & ObjCDeclSpec::DQ_Bycopy)
1468    ret = (Decl::ObjCDeclQualifier)(ret | Decl::OBJC_TQ_Bycopy);
1469  if (PQTVal & ObjCDeclSpec::DQ_Byref)
1470    ret = (Decl::ObjCDeclQualifier)(ret | Decl::OBJC_TQ_Byref);
1471  if (PQTVal & ObjCDeclSpec::DQ_Oneway)
1472    ret = (Decl::ObjCDeclQualifier)(ret | Decl::OBJC_TQ_Oneway);
1473
1474  return ret;
1475}
1476
1477Sema::DeclPtrTy Sema::ActOnMethodDeclaration(
1478    SourceLocation MethodLoc, SourceLocation EndLoc,
1479    tok::TokenKind MethodType, DeclPtrTy classDecl,
1480    ObjCDeclSpec &ReturnQT, TypeTy *ReturnType,
1481    Selector Sel,
1482    // optional arguments. The number of types/arguments is obtained
1483    // from the Sel.getNumArgs().
1484    ObjCArgInfo *ArgInfo,
1485    llvm::SmallVectorImpl<Declarator> &Cdecls,
1486    AttributeList *AttrList, tok::ObjCKeywordKind MethodDeclKind,
1487    bool isVariadic) {
1488  Decl *ClassDecl = classDecl.getAs<Decl>();
1489
1490  // Make sure we can establish a context for the method.
1491  if (!ClassDecl) {
1492    Diag(MethodLoc, diag::error_missing_method_context);
1493    getLabelMap().clear();
1494    return DeclPtrTy();
1495  }
1496  QualType resultDeclType;
1497
1498  TypeSourceInfo *ResultTInfo = 0;
1499  if (ReturnType) {
1500    resultDeclType = GetTypeFromParser(ReturnType, &ResultTInfo);
1501
1502    // Methods cannot return interface types. All ObjC objects are
1503    // passed by reference.
1504    if (resultDeclType->isObjCInterfaceType()) {
1505      Diag(MethodLoc, diag::err_object_cannot_be_passed_returned_by_value)
1506        << 0 << resultDeclType;
1507      return DeclPtrTy();
1508    }
1509  } else // get the type for "id".
1510    resultDeclType = Context.getObjCIdType();
1511
1512  ObjCMethodDecl* ObjCMethod =
1513    ObjCMethodDecl::Create(Context, MethodLoc, EndLoc, Sel, resultDeclType,
1514                           ResultTInfo,
1515                           cast<DeclContext>(ClassDecl),
1516                           MethodType == tok::minus, isVariadic,
1517                           false,
1518                           MethodDeclKind == tok::objc_optional ?
1519                           ObjCMethodDecl::Optional :
1520                           ObjCMethodDecl::Required);
1521
1522  llvm::SmallVector<ParmVarDecl*, 16> Params;
1523
1524  for (unsigned i = 0, e = Sel.getNumArgs(); i != e; ++i) {
1525    QualType ArgType;
1526    TypeSourceInfo *DI;
1527
1528    if (ArgInfo[i].Type == 0) {
1529      ArgType = Context.getObjCIdType();
1530      DI = 0;
1531    } else {
1532      ArgType = GetTypeFromParser(ArgInfo[i].Type, &DI);
1533      // Perform the default array/function conversions (C99 6.7.5.3p[7,8]).
1534      ArgType = adjustParameterType(ArgType);
1535    }
1536
1537    ParmVarDecl* Param
1538      = ParmVarDecl::Create(Context, ObjCMethod, ArgInfo[i].NameLoc,
1539                            ArgInfo[i].Name, ArgType, DI,
1540                            VarDecl::None, 0);
1541
1542    if (ArgType->isObjCInterfaceType()) {
1543      Diag(ArgInfo[i].NameLoc,
1544           diag::err_object_cannot_be_passed_returned_by_value)
1545        << 1 << ArgType;
1546      Param->setInvalidDecl();
1547    }
1548
1549    Param->setObjCDeclQualifier(
1550      CvtQTToAstBitMask(ArgInfo[i].DeclSpec.getObjCDeclQualifier()));
1551
1552    // Apply the attributes to the parameter.
1553    ProcessDeclAttributeList(TUScope, Param, ArgInfo[i].ArgAttrs);
1554
1555    Params.push_back(Param);
1556  }
1557
1558  ObjCMethod->setMethodParams(Context, Params.data(), Sel.getNumArgs());
1559  ObjCMethod->setObjCDeclQualifier(
1560    CvtQTToAstBitMask(ReturnQT.getObjCDeclQualifier()));
1561  const ObjCMethodDecl *PrevMethod = 0;
1562
1563  if (AttrList)
1564    ProcessDeclAttributeList(TUScope, ObjCMethod, AttrList);
1565
1566  const ObjCMethodDecl *InterfaceMD = 0;
1567
1568  // For implementations (which can be very "coarse grain"), we add the
1569  // method now. This allows the AST to implement lookup methods that work
1570  // incrementally (without waiting until we parse the @end). It also allows
1571  // us to flag multiple declaration errors as they occur.
1572  if (ObjCImplementationDecl *ImpDecl =
1573        dyn_cast<ObjCImplementationDecl>(ClassDecl)) {
1574    if (MethodType == tok::minus) {
1575      PrevMethod = ImpDecl->getInstanceMethod(Sel);
1576      ImpDecl->addInstanceMethod(ObjCMethod);
1577    } else {
1578      PrevMethod = ImpDecl->getClassMethod(Sel);
1579      ImpDecl->addClassMethod(ObjCMethod);
1580    }
1581    InterfaceMD = ImpDecl->getClassInterface()->getMethod(Sel,
1582                                                   MethodType == tok::minus);
1583    if (AttrList)
1584      Diag(EndLoc, diag::warn_attribute_method_def);
1585  } else if (ObjCCategoryImplDecl *CatImpDecl =
1586             dyn_cast<ObjCCategoryImplDecl>(ClassDecl)) {
1587    if (MethodType == tok::minus) {
1588      PrevMethod = CatImpDecl->getInstanceMethod(Sel);
1589      CatImpDecl->addInstanceMethod(ObjCMethod);
1590    } else {
1591      PrevMethod = CatImpDecl->getClassMethod(Sel);
1592      CatImpDecl->addClassMethod(ObjCMethod);
1593    }
1594    if (AttrList)
1595      Diag(EndLoc, diag::warn_attribute_method_def);
1596  }
1597  if (PrevMethod) {
1598    // You can never have two method definitions with the same name.
1599    Diag(ObjCMethod->getLocation(), diag::err_duplicate_method_decl)
1600      << ObjCMethod->getDeclName();
1601    Diag(PrevMethod->getLocation(), diag::note_previous_declaration);
1602  }
1603
1604  // If the interface declared this method, and it was deprecated there,
1605  // mark it deprecated here.
1606  if (InterfaceMD && InterfaceMD->hasAttr<DeprecatedAttr>())
1607    ObjCMethod->addAttr(::new (Context) DeprecatedAttr());
1608
1609  return DeclPtrTy::make(ObjCMethod);
1610}
1611
1612bool Sema::CheckObjCDeclScope(Decl *D) {
1613  if (isa<TranslationUnitDecl>(CurContext->getLookupContext()))
1614    return false;
1615
1616  Diag(D->getLocation(), diag::err_objc_decls_may_only_appear_in_global_scope);
1617  D->setInvalidDecl();
1618
1619  return true;
1620}
1621
1622/// Called whenever @defs(ClassName) is encountered in the source.  Inserts the
1623/// instance variables of ClassName into Decls.
1624void Sema::ActOnDefs(Scope *S, DeclPtrTy TagD, SourceLocation DeclStart,
1625                     IdentifierInfo *ClassName,
1626                     llvm::SmallVectorImpl<DeclPtrTy> &Decls) {
1627  // Check that ClassName is a valid class
1628  ObjCInterfaceDecl *Class = getObjCInterfaceDecl(ClassName);
1629  if (!Class) {
1630    Diag(DeclStart, diag::err_undef_interface) << ClassName;
1631    return;
1632  }
1633  if (LangOpts.ObjCNonFragileABI) {
1634    Diag(DeclStart, diag::err_atdef_nonfragile_interface);
1635    return;
1636  }
1637
1638  // Collect the instance variables
1639  llvm::SmallVector<FieldDecl*, 32> RecFields;
1640  Context.CollectObjCIvars(Class, RecFields);
1641  // For each ivar, create a fresh ObjCAtDefsFieldDecl.
1642  for (unsigned i = 0; i < RecFields.size(); i++) {
1643    FieldDecl* ID = RecFields[i];
1644    RecordDecl *Record = dyn_cast<RecordDecl>(TagD.getAs<Decl>());
1645    Decl *FD = ObjCAtDefsFieldDecl::Create(Context, Record, ID->getLocation(),
1646                                           ID->getIdentifier(), ID->getType(),
1647                                           ID->getBitWidth());
1648    Decls.push_back(Sema::DeclPtrTy::make(FD));
1649  }
1650
1651  // Introduce all of these fields into the appropriate scope.
1652  for (llvm::SmallVectorImpl<DeclPtrTy>::iterator D = Decls.begin();
1653       D != Decls.end(); ++D) {
1654    FieldDecl *FD = cast<FieldDecl>(D->getAs<Decl>());
1655    if (getLangOptions().CPlusPlus)
1656      PushOnScopeChains(cast<FieldDecl>(FD), S);
1657    else if (RecordDecl *Record = dyn_cast<RecordDecl>(TagD.getAs<Decl>()))
1658      Record->addDecl(FD);
1659  }
1660}
1661
1662