clang  12.0.0git
SemaDeclObjC.cpp
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1 //===--- SemaDeclObjC.cpp - Semantic Analysis for ObjC Declarations -------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // This file implements semantic analysis for Objective C declarations.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #include "TypeLocBuilder.h"
14 #include "clang/AST/ASTConsumer.h"
15 #include "clang/AST/ASTContext.h"
17 #include "clang/AST/DeclObjC.h"
18 #include "clang/AST/Expr.h"
19 #include "clang/AST/ExprObjC.h"
22 #include "clang/Basic/TargetInfo.h"
23 #include "clang/Sema/DeclSpec.h"
24 #include "clang/Sema/Lookup.h"
25 #include "clang/Sema/Scope.h"
26 #include "clang/Sema/ScopeInfo.h"
28 #include "llvm/ADT/DenseMap.h"
29 #include "llvm/ADT/DenseSet.h"
30 
31 using namespace clang;
32 
33 /// Check whether the given method, which must be in the 'init'
34 /// family, is a valid member of that family.
35 ///
36 /// \param receiverTypeIfCall - if null, check this as if declaring it;
37 /// if non-null, check this as if making a call to it with the given
38 /// receiver type
39 ///
40 /// \return true to indicate that there was an error and appropriate
41 /// actions were taken
43  QualType receiverTypeIfCall) {
44  if (method->isInvalidDecl()) return true;
45 
46  // This castAs is safe: methods that don't return an object
47  // pointer won't be inferred as inits and will reject an explicit
48  // objc_method_family(init).
49 
50  // We ignore protocols here. Should we? What about Class?
51 
52  const ObjCObjectType *result =
54 
55  if (result->isObjCId()) {
56  return false;
57  } else if (result->isObjCClass()) {
58  // fall through: always an error
59  } else {
60  ObjCInterfaceDecl *resultClass = result->getInterface();
61  assert(resultClass && "unexpected object type!");
62 
63  // It's okay for the result type to still be a forward declaration
64  // if we're checking an interface declaration.
65  if (!resultClass->hasDefinition()) {
66  if (receiverTypeIfCall.isNull() &&
67  !isa<ObjCImplementationDecl>(method->getDeclContext()))
68  return false;
69 
70  // Otherwise, we try to compare class types.
71  } else {
72  // If this method was declared in a protocol, we can't check
73  // anything unless we have a receiver type that's an interface.
74  const ObjCInterfaceDecl *receiverClass = nullptr;
75  if (isa<ObjCProtocolDecl>(method->getDeclContext())) {
76  if (receiverTypeIfCall.isNull())
77  return false;
78 
79  receiverClass = receiverTypeIfCall->castAs<ObjCObjectPointerType>()
80  ->getInterfaceDecl();
81 
82  // This can be null for calls to e.g. id<Foo>.
83  if (!receiverClass) return false;
84  } else {
85  receiverClass = method->getClassInterface();
86  assert(receiverClass && "method not associated with a class!");
87  }
88 
89  // If either class is a subclass of the other, it's fine.
90  if (receiverClass->isSuperClassOf(resultClass) ||
91  resultClass->isSuperClassOf(receiverClass))
92  return false;
93  }
94  }
95 
96  SourceLocation loc = method->getLocation();
97 
98  // If we're in a system header, and this is not a call, just make
99  // the method unusable.
100  if (receiverTypeIfCall.isNull() && getSourceManager().isInSystemHeader(loc)) {
101  method->addAttr(UnavailableAttr::CreateImplicit(Context, "",
102  UnavailableAttr::IR_ARCInitReturnsUnrelated, loc));
103  return true;
104  }
105 
106  // Otherwise, it's an error.
107  Diag(loc, diag::err_arc_init_method_unrelated_result_type);
108  method->setInvalidDecl();
109  return true;
110 }
111 
112 /// Issue a warning if the parameter of the overridden method is non-escaping
113 /// but the parameter of the overriding method is not.
114 static bool diagnoseNoescape(const ParmVarDecl *NewD, const ParmVarDecl *OldD,
115  Sema &S) {
116  if (OldD->hasAttr<NoEscapeAttr>() && !NewD->hasAttr<NoEscapeAttr>()) {
117  S.Diag(NewD->getLocation(), diag::warn_overriding_method_missing_noescape);
118  S.Diag(OldD->getLocation(), diag::note_overridden_marked_noescape);
119  return false;
120  }
121 
122  return true;
123 }
124 
125 /// Produce additional diagnostics if a category conforms to a protocol that
126 /// defines a method taking a non-escaping parameter.
127 static void diagnoseNoescape(const ParmVarDecl *NewD, const ParmVarDecl *OldD,
128  const ObjCCategoryDecl *CD,
129  const ObjCProtocolDecl *PD, Sema &S) {
130  if (!diagnoseNoescape(NewD, OldD, S))
131  S.Diag(CD->getLocation(), diag::note_cat_conform_to_noescape_prot)
132  << CD->IsClassExtension() << PD
133  << cast<ObjCMethodDecl>(NewD->getDeclContext());
134 }
135 
137  const ObjCMethodDecl *Overridden) {
138  if (Overridden->hasRelatedResultType() &&
139  !NewMethod->hasRelatedResultType()) {
140  // This can only happen when the method follows a naming convention that
141  // implies a related result type, and the original (overridden) method has
142  // a suitable return type, but the new (overriding) method does not have
143  // a suitable return type.
144  QualType ResultType = NewMethod->getReturnType();
145  SourceRange ResultTypeRange = NewMethod->getReturnTypeSourceRange();
146 
147  // Figure out which class this method is part of, if any.
148  ObjCInterfaceDecl *CurrentClass
149  = dyn_cast<ObjCInterfaceDecl>(NewMethod->getDeclContext());
150  if (!CurrentClass) {
151  DeclContext *DC = NewMethod->getDeclContext();
152  if (ObjCCategoryDecl *Cat = dyn_cast<ObjCCategoryDecl>(DC))
153  CurrentClass = Cat->getClassInterface();
154  else if (ObjCImplDecl *Impl = dyn_cast<ObjCImplDecl>(DC))
155  CurrentClass = Impl->getClassInterface();
156  else if (ObjCCategoryImplDecl *CatImpl
157  = dyn_cast<ObjCCategoryImplDecl>(DC))
158  CurrentClass = CatImpl->getClassInterface();
159  }
160 
161  if (CurrentClass) {
162  Diag(NewMethod->getLocation(),
163  diag::warn_related_result_type_compatibility_class)
164  << Context.getObjCInterfaceType(CurrentClass)
165  << ResultType
166  << ResultTypeRange;
167  } else {
168  Diag(NewMethod->getLocation(),
169  diag::warn_related_result_type_compatibility_protocol)
170  << ResultType
171  << ResultTypeRange;
172  }
173 
174  if (ObjCMethodFamily Family = Overridden->getMethodFamily())
175  Diag(Overridden->getLocation(),
176  diag::note_related_result_type_family)
177  << /*overridden method*/ 0
178  << Family;
179  else
180  Diag(Overridden->getLocation(),
181  diag::note_related_result_type_overridden);
182  }
183 
184  if ((NewMethod->hasAttr<NSReturnsRetainedAttr>() !=
185  Overridden->hasAttr<NSReturnsRetainedAttr>())) {
186  Diag(NewMethod->getLocation(),
187  getLangOpts().ObjCAutoRefCount
188  ? diag::err_nsreturns_retained_attribute_mismatch
189  : diag::warn_nsreturns_retained_attribute_mismatch)
190  << 1;
191  Diag(Overridden->getLocation(), diag::note_previous_decl) << "method";
192  }
193  if ((NewMethod->hasAttr<NSReturnsNotRetainedAttr>() !=
194  Overridden->hasAttr<NSReturnsNotRetainedAttr>())) {
195  Diag(NewMethod->getLocation(),
196  getLangOpts().ObjCAutoRefCount
197  ? diag::err_nsreturns_retained_attribute_mismatch
198  : diag::warn_nsreturns_retained_attribute_mismatch)
199  << 0;
200  Diag(Overridden->getLocation(), diag::note_previous_decl) << "method";
201  }
202 
204  oe = Overridden->param_end();
205  for (ObjCMethodDecl::param_iterator ni = NewMethod->param_begin(),
206  ne = NewMethod->param_end();
207  ni != ne && oi != oe; ++ni, ++oi) {
208  const ParmVarDecl *oldDecl = (*oi);
209  ParmVarDecl *newDecl = (*ni);
210  if (newDecl->hasAttr<NSConsumedAttr>() !=
211  oldDecl->hasAttr<NSConsumedAttr>()) {
212  Diag(newDecl->getLocation(),
213  getLangOpts().ObjCAutoRefCount
214  ? diag::err_nsconsumed_attribute_mismatch
215  : diag::warn_nsconsumed_attribute_mismatch);
216  Diag(oldDecl->getLocation(), diag::note_previous_decl) << "parameter";
217  }
218 
219  diagnoseNoescape(newDecl, oldDecl, *this);
220  }
221 }
222 
223 /// Check a method declaration for compatibility with the Objective-C
224 /// ARC conventions.
226  ObjCMethodFamily family = method->getMethodFamily();
227  switch (family) {
228  case OMF_None:
229  case OMF_finalize:
230  case OMF_retain:
231  case OMF_release:
232  case OMF_autorelease:
233  case OMF_retainCount:
234  case OMF_self:
235  case OMF_initialize:
236  case OMF_performSelector:
237  return false;
238 
239  case OMF_dealloc:
240  if (!Context.hasSameType(method->getReturnType(), Context.VoidTy)) {
241  SourceRange ResultTypeRange = method->getReturnTypeSourceRange();
242  if (ResultTypeRange.isInvalid())
243  Diag(method->getLocation(), diag::err_dealloc_bad_result_type)
244  << method->getReturnType()
245  << FixItHint::CreateInsertion(method->getSelectorLoc(0), "(void)");
246  else
247  Diag(method->getLocation(), diag::err_dealloc_bad_result_type)
248  << method->getReturnType()
249  << FixItHint::CreateReplacement(ResultTypeRange, "void");
250  return true;
251  }
252  return false;
253 
254  case OMF_init:
255  // If the method doesn't obey the init rules, don't bother annotating it.
256  if (checkInitMethod(method, QualType()))
257  return true;
258 
259  method->addAttr(NSConsumesSelfAttr::CreateImplicit(Context));
260 
261  // Don't add a second copy of this attribute, but otherwise don't
262  // let it be suppressed.
263  if (method->hasAttr<NSReturnsRetainedAttr>())
264  return false;
265  break;
266 
267  case OMF_alloc:
268  case OMF_copy:
269  case OMF_mutableCopy:
270  case OMF_new:
271  if (method->hasAttr<NSReturnsRetainedAttr>() ||
272  method->hasAttr<NSReturnsNotRetainedAttr>() ||
273  method->hasAttr<NSReturnsAutoreleasedAttr>())
274  return false;
275  break;
276  }
277 
278  method->addAttr(NSReturnsRetainedAttr::CreateImplicit(Context));
279  return false;
280 }
281 
283  SourceLocation ImplLoc) {
284  if (!ND)
285  return;
286  bool IsCategory = false;
287  StringRef RealizedPlatform;
288  AvailabilityResult Availability = ND->getAvailability(
289  /*Message=*/nullptr, /*EnclosingVersion=*/VersionTuple(),
290  &RealizedPlatform);
291  if (Availability != AR_Deprecated) {
292  if (isa<ObjCMethodDecl>(ND)) {
293  if (Availability != AR_Unavailable)
294  return;
295  if (RealizedPlatform.empty())
296  RealizedPlatform = S.Context.getTargetInfo().getPlatformName();
297  // Warn about implementing unavailable methods, unless the unavailable
298  // is for an app extension.
299  if (RealizedPlatform.endswith("_app_extension"))
300  return;
301  S.Diag(ImplLoc, diag::warn_unavailable_def);
302  S.Diag(ND->getLocation(), diag::note_method_declared_at)
303  << ND->getDeclName();
304  return;
305  }
306  if (const auto *CD = dyn_cast<ObjCCategoryDecl>(ND)) {
307  if (!CD->getClassInterface()->isDeprecated())
308  return;
309  ND = CD->getClassInterface();
310  IsCategory = true;
311  } else
312  return;
313  }
314  S.Diag(ImplLoc, diag::warn_deprecated_def)
315  << (isa<ObjCMethodDecl>(ND)
316  ? /*Method*/ 0
317  : isa<ObjCCategoryDecl>(ND) || IsCategory ? /*Category*/ 2
318  : /*Class*/ 1);
319  if (isa<ObjCMethodDecl>(ND))
320  S.Diag(ND->getLocation(), diag::note_method_declared_at)
321  << ND->getDeclName();
322  else
323  S.Diag(ND->getLocation(), diag::note_previous_decl)
324  << (isa<ObjCCategoryDecl>(ND) ? "category" : "class");
325 }
326 
327 /// AddAnyMethodToGlobalPool - Add any method, instance or factory to global
328 /// pool.
330  ObjCMethodDecl *MDecl = dyn_cast_or_null<ObjCMethodDecl>(D);
331 
332  // If we don't have a valid method decl, simply return.
333  if (!MDecl)
334  return;
335  if (MDecl->isInstanceMethod())
336  AddInstanceMethodToGlobalPool(MDecl, true);
337  else
338  AddFactoryMethodToGlobalPool(MDecl, true);
339 }
340 
341 /// HasExplicitOwnershipAttr - returns true when pointer to ObjC pointer
342 /// has explicit ownership attribute; false otherwise.
343 static bool
345  QualType T = Param->getType();
346 
347  if (const PointerType *PT = T->getAs<PointerType>()) {
348  T = PT->getPointeeType();
349  } else if (const ReferenceType *RT = T->getAs<ReferenceType>()) {
350  T = RT->getPointeeType();
351  } else {
352  return true;
353  }
354 
355  // If we have a lifetime qualifier, but it's local, we must have
356  // inferred it. So, it is implicit.
357  return !T.getLocalQualifiers().hasObjCLifetime();
358 }
359 
360 /// ActOnStartOfObjCMethodDef - This routine sets up parameters; invisible
361 /// and user declared, in the method definition's AST.
364  assert((getCurMethodDecl() == nullptr) && "Methodparsing confused");
365  ObjCMethodDecl *MDecl = dyn_cast_or_null<ObjCMethodDecl>(D);
366 
368 
369  // If we don't have a valid method decl, simply return.
370  if (!MDecl)
371  return;
372 
373  QualType ResultType = MDecl->getReturnType();
374  if (!ResultType->isDependentType() && !ResultType->isVoidType() &&
375  !MDecl->isInvalidDecl() &&
376  RequireCompleteType(MDecl->getLocation(), ResultType,
377  diag::err_func_def_incomplete_result))
378  MDecl->setInvalidDecl();
379 
380  // Allow all of Sema to see that we are entering a method definition.
381  PushDeclContext(FnBodyScope, MDecl);
383 
384  // Create Decl objects for each parameter, entrring them in the scope for
385  // binding to their use.
386 
387  // Insert the invisible arguments, self and _cmd!
389 
390  PushOnScopeChains(MDecl->getSelfDecl(), FnBodyScope);
391  PushOnScopeChains(MDecl->getCmdDecl(), FnBodyScope);
392 
393  // The ObjC parser requires parameter names so there's no need to check.
395  /*CheckParameterNames=*/false);
396 
397  // Introduce all of the other parameters into this scope.
398  for (auto *Param : MDecl->parameters()) {
399  if (!Param->isInvalidDecl() &&
400  getLangOpts().ObjCAutoRefCount &&
401  !HasExplicitOwnershipAttr(*this, Param))
402  Diag(Param->getLocation(), diag::warn_arc_strong_pointer_objc_pointer) <<
403  Param->getType();
404 
405  if (Param->getIdentifier())
406  PushOnScopeChains(Param, FnBodyScope);
407  }
408 
409  // In ARC, disallow definition of retain/release/autorelease/retainCount
410  if (getLangOpts().ObjCAutoRefCount) {
411  switch (MDecl->getMethodFamily()) {
412  case OMF_retain:
413  case OMF_retainCount:
414  case OMF_release:
415  case OMF_autorelease:
416  Diag(MDecl->getLocation(), diag::err_arc_illegal_method_def)
417  << 0 << MDecl->getSelector();
418  break;
419 
420  case OMF_None:
421  case OMF_dealloc:
422  case OMF_finalize:
423  case OMF_alloc:
424  case OMF_init:
425  case OMF_mutableCopy:
426  case OMF_copy:
427  case OMF_new:
428  case OMF_self:
429  case OMF_initialize:
430  case OMF_performSelector:
431  break;
432  }
433  }
434 
435  // Warn on deprecated methods under -Wdeprecated-implementations,
436  // and prepare for warning on missing super calls.
437  if (ObjCInterfaceDecl *IC = MDecl->getClassInterface()) {
438  ObjCMethodDecl *IMD =
439  IC->lookupMethod(MDecl->getSelector(), MDecl->isInstanceMethod());
440 
441  if (IMD) {
442  ObjCImplDecl *ImplDeclOfMethodDef =
443  dyn_cast<ObjCImplDecl>(MDecl->getDeclContext());
444  ObjCContainerDecl *ContDeclOfMethodDecl =
445  dyn_cast<ObjCContainerDecl>(IMD->getDeclContext());
446  ObjCImplDecl *ImplDeclOfMethodDecl = nullptr;
447  if (ObjCInterfaceDecl *OID = dyn_cast<ObjCInterfaceDecl>(ContDeclOfMethodDecl))
448  ImplDeclOfMethodDecl = OID->getImplementation();
449  else if (ObjCCategoryDecl *CD = dyn_cast<ObjCCategoryDecl>(ContDeclOfMethodDecl)) {
450  if (CD->IsClassExtension()) {
451  if (ObjCInterfaceDecl *OID = CD->getClassInterface())
452  ImplDeclOfMethodDecl = OID->getImplementation();
453  } else
454  ImplDeclOfMethodDecl = CD->getImplementation();
455  }
456  // No need to issue deprecated warning if deprecated mehod in class/category
457  // is being implemented in its own implementation (no overriding is involved).
458  if (!ImplDeclOfMethodDecl || ImplDeclOfMethodDecl != ImplDeclOfMethodDef)
459  DiagnoseObjCImplementedDeprecations(*this, IMD, MDecl->getLocation());
460  }
461 
462  if (MDecl->getMethodFamily() == OMF_init) {
466  IC->getSuperClass() != nullptr;
467  } else if (IC->hasDesignatedInitializers()) {
470  }
471  }
472 
473  // If this is "dealloc" or "finalize", set some bit here.
474  // Then in ActOnSuperMessage() (SemaExprObjC), set it back to false.
475  // Finally, in ActOnFinishFunctionBody() (SemaDecl), warn if flag is set.
476  // Only do this if the current class actually has a superclass.
477  if (const ObjCInterfaceDecl *SuperClass = IC->getSuperClass()) {
478  ObjCMethodFamily Family = MDecl->getMethodFamily();
479  if (Family == OMF_dealloc) {
480  if (!(getLangOpts().ObjCAutoRefCount ||
481  getLangOpts().getGC() == LangOptions::GCOnly))
483 
484  } else if (Family == OMF_finalize) {
485  if (Context.getLangOpts().getGC() != LangOptions::NonGC)
487 
488  } else {
489  const ObjCMethodDecl *SuperMethod =
490  SuperClass->lookupMethod(MDecl->getSelector(),
491  MDecl->isInstanceMethod());
493  (SuperMethod && SuperMethod->hasAttr<ObjCRequiresSuperAttr>());
494  }
495  }
496  }
497 }
498 
499 namespace {
500 
501 // Callback to only accept typo corrections that are Objective-C classes.
502 // If an ObjCInterfaceDecl* is given to the constructor, then the validation
503 // function will reject corrections to that class.
504 class ObjCInterfaceValidatorCCC final : public CorrectionCandidateCallback {
505  public:
506  ObjCInterfaceValidatorCCC() : CurrentIDecl(nullptr) {}
507  explicit ObjCInterfaceValidatorCCC(ObjCInterfaceDecl *IDecl)
508  : CurrentIDecl(IDecl) {}
509 
510  bool ValidateCandidate(const TypoCorrection &candidate) override {
512  return ID && !declaresSameEntity(ID, CurrentIDecl);
513  }
514 
515  std::unique_ptr<CorrectionCandidateCallback> clone() override {
516  return std::make_unique<ObjCInterfaceValidatorCCC>(*this);
517  }
518 
519  private:
520  ObjCInterfaceDecl *CurrentIDecl;
521 };
522 
523 } // end anonymous namespace
524 
525 static void diagnoseUseOfProtocols(Sema &TheSema,
526  ObjCContainerDecl *CD,
527  ObjCProtocolDecl *const *ProtoRefs,
528  unsigned NumProtoRefs,
529  const SourceLocation *ProtoLocs) {
530  assert(ProtoRefs);
531  // Diagnose availability in the context of the ObjC container.
532  Sema::ContextRAII SavedContext(TheSema, CD);
533  for (unsigned i = 0; i < NumProtoRefs; ++i) {
534  (void)TheSema.DiagnoseUseOfDecl(ProtoRefs[i], ProtoLocs[i],
535  /*UnknownObjCClass=*/nullptr,
536  /*ObjCPropertyAccess=*/false,
537  /*AvoidPartialAvailabilityChecks=*/true);
538  }
539 }
540 
541 void Sema::
543  SourceLocation AtInterfaceLoc,
544  ObjCInterfaceDecl *IDecl,
545  IdentifierInfo *ClassName,
546  SourceLocation ClassLoc,
547  IdentifierInfo *SuperName,
548  SourceLocation SuperLoc,
549  ArrayRef<ParsedType> SuperTypeArgs,
550  SourceRange SuperTypeArgsRange) {
551  // Check if a different kind of symbol declared in this scope.
552  NamedDecl *PrevDecl = LookupSingleName(TUScope, SuperName, SuperLoc,
554 
555  if (!PrevDecl) {
556  // Try to correct for a typo in the superclass name without correcting
557  // to the class we're defining.
558  ObjCInterfaceValidatorCCC CCC(IDecl);
559  if (TypoCorrection Corrected = CorrectTypo(
560  DeclarationNameInfo(SuperName, SuperLoc), LookupOrdinaryName,
561  TUScope, nullptr, CCC, CTK_ErrorRecovery)) {
562  diagnoseTypo(Corrected, PDiag(diag::err_undef_superclass_suggest)
563  << SuperName << ClassName);
564  PrevDecl = Corrected.getCorrectionDeclAs<ObjCInterfaceDecl>();
565  }
566  }
567 
568  if (declaresSameEntity(PrevDecl, IDecl)) {
569  Diag(SuperLoc, diag::err_recursive_superclass)
570  << SuperName << ClassName << SourceRange(AtInterfaceLoc, ClassLoc);
571  IDecl->setEndOfDefinitionLoc(ClassLoc);
572  } else {
573  ObjCInterfaceDecl *SuperClassDecl =
574  dyn_cast_or_null<ObjCInterfaceDecl>(PrevDecl);
575  QualType SuperClassType;
576 
577  // Diagnose classes that inherit from deprecated classes.
578  if (SuperClassDecl) {
579  (void)DiagnoseUseOfDecl(SuperClassDecl, SuperLoc);
580  SuperClassType = Context.getObjCInterfaceType(SuperClassDecl);
581  }
582 
583  if (PrevDecl && !SuperClassDecl) {
584  // The previous declaration was not a class decl. Check if we have a
585  // typedef. If we do, get the underlying class type.
586  if (const TypedefNameDecl *TDecl =
587  dyn_cast_or_null<TypedefNameDecl>(PrevDecl)) {
588  QualType T = TDecl->getUnderlyingType();
589  if (T->isObjCObjectType()) {
590  if (NamedDecl *IDecl = T->castAs<ObjCObjectType>()->getInterface()) {
591  SuperClassDecl = dyn_cast<ObjCInterfaceDecl>(IDecl);
592  SuperClassType = Context.getTypeDeclType(TDecl);
593 
594  // This handles the following case:
595  // @interface NewI @end
596  // typedef NewI DeprI __attribute__((deprecated("blah")))
597  // @interface SI : DeprI /* warn here */ @end
598  (void)DiagnoseUseOfDecl(const_cast<TypedefNameDecl*>(TDecl), SuperLoc);
599  }
600  }
601  }
602 
603  // This handles the following case:
604  //
605  // typedef int SuperClass;
606  // @interface MyClass : SuperClass {} @end
607  //
608  if (!SuperClassDecl) {
609  Diag(SuperLoc, diag::err_redefinition_different_kind) << SuperName;
610  Diag(PrevDecl->getLocation(), diag::note_previous_definition);
611  }
612  }
613 
614  if (!dyn_cast_or_null<TypedefNameDecl>(PrevDecl)) {
615  if (!SuperClassDecl)
616  Diag(SuperLoc, diag::err_undef_superclass)
617  << SuperName << ClassName << SourceRange(AtInterfaceLoc, ClassLoc);
618  else if (RequireCompleteType(SuperLoc,
619  SuperClassType,
620  diag::err_forward_superclass,
621  SuperClassDecl->getDeclName(),
622  ClassName,
623  SourceRange(AtInterfaceLoc, ClassLoc))) {
624  SuperClassDecl = nullptr;
625  SuperClassType = QualType();
626  }
627  }
628 
629  if (SuperClassType.isNull()) {
630  assert(!SuperClassDecl && "Failed to set SuperClassType?");
631  return;
632  }
633 
634  // Handle type arguments on the superclass.
635  TypeSourceInfo *SuperClassTInfo = nullptr;
636  if (!SuperTypeArgs.empty()) {
638  S,
639  SuperLoc,
640  CreateParsedType(SuperClassType,
641  nullptr),
642  SuperTypeArgsRange.getBegin(),
643  SuperTypeArgs,
644  SuperTypeArgsRange.getEnd(),
645  SourceLocation(),
646  { },
647  { },
648  SourceLocation());
649  if (!fullSuperClassType.isUsable())
650  return;
651 
652  SuperClassType = GetTypeFromParser(fullSuperClassType.get(),
653  &SuperClassTInfo);
654  }
655 
656  if (!SuperClassTInfo) {
657  SuperClassTInfo = Context.getTrivialTypeSourceInfo(SuperClassType,
658  SuperLoc);
659  }
660 
661  IDecl->setSuperClass(SuperClassTInfo);
662  IDecl->setEndOfDefinitionLoc(SuperClassTInfo->getTypeLoc().getEndLoc());
663  }
664 }
665 
667  ObjCTypeParamVariance variance,
668  SourceLocation varianceLoc,
669  unsigned index,
670  IdentifierInfo *paramName,
671  SourceLocation paramLoc,
672  SourceLocation colonLoc,
673  ParsedType parsedTypeBound) {
674  // If there was an explicitly-provided type bound, check it.
675  TypeSourceInfo *typeBoundInfo = nullptr;
676  if (parsedTypeBound) {
677  // The type bound can be any Objective-C pointer type.
678  QualType typeBound = GetTypeFromParser(parsedTypeBound, &typeBoundInfo);
679  if (typeBound->isObjCObjectPointerType()) {
680  // okay
681  } else if (typeBound->isObjCObjectType()) {
682  // The user forgot the * on an Objective-C pointer type, e.g.,
683  // "T : NSView".
685  typeBoundInfo->getTypeLoc().getEndLoc());
686  Diag(typeBoundInfo->getTypeLoc().getBeginLoc(),
687  diag::err_objc_type_param_bound_missing_pointer)
688  << typeBound << paramName
689  << FixItHint::CreateInsertion(starLoc, " *");
690 
691  // Create a new type location builder so we can update the type
692  // location information we have.
693  TypeLocBuilder builder;
694  builder.pushFullCopy(typeBoundInfo->getTypeLoc());
695 
696  // Create the Objective-C pointer type.
697  typeBound = Context.getObjCObjectPointerType(typeBound);
699  = builder.push<ObjCObjectPointerTypeLoc>(typeBound);
700  newT.setStarLoc(starLoc);
701 
702  // Form the new type source information.
703  typeBoundInfo = builder.getTypeSourceInfo(Context, typeBound);
704  } else {
705  // Not a valid type bound.
706  Diag(typeBoundInfo->getTypeLoc().getBeginLoc(),
707  diag::err_objc_type_param_bound_nonobject)
708  << typeBound << paramName;
709 
710  // Forget the bound; we'll default to id later.
711  typeBoundInfo = nullptr;
712  }
713 
714  // Type bounds cannot have qualifiers (even indirectly) or explicit
715  // nullability.
716  if (typeBoundInfo) {
717  QualType typeBound = typeBoundInfo->getType();
718  TypeLoc qual = typeBoundInfo->getTypeLoc().findExplicitQualifierLoc();
719  if (qual || typeBound.hasQualifiers()) {
720  bool diagnosed = false;
721  SourceRange rangeToRemove;
722  if (qual) {
723  if (auto attr = qual.getAs<AttributedTypeLoc>()) {
724  rangeToRemove = attr.getLocalSourceRange();
725  if (attr.getTypePtr()->getImmediateNullability()) {
726  Diag(attr.getBeginLoc(),
727  diag::err_objc_type_param_bound_explicit_nullability)
728  << paramName << typeBound
729  << FixItHint::CreateRemoval(rangeToRemove);
730  diagnosed = true;
731  }
732  }
733  }
734 
735  if (!diagnosed) {
736  Diag(qual ? qual.getBeginLoc()
737  : typeBoundInfo->getTypeLoc().getBeginLoc(),
738  diag::err_objc_type_param_bound_qualified)
739  << paramName << typeBound
740  << typeBound.getQualifiers().getAsString()
741  << FixItHint::CreateRemoval(rangeToRemove);
742  }
743 
744  // If the type bound has qualifiers other than CVR, we need to strip
745  // them or we'll probably assert later when trying to apply new
746  // qualifiers.
747  Qualifiers quals = typeBound.getQualifiers();
748  quals.removeCVRQualifiers();
749  if (!quals.empty()) {
750  typeBoundInfo =
752  }
753  }
754  }
755  }
756 
757  // If there was no explicit type bound (or we removed it due to an error),
758  // use 'id' instead.
759  if (!typeBoundInfo) {
760  colonLoc = SourceLocation();
762  }
763 
764  // Create the type parameter.
765  return ObjCTypeParamDecl::Create(Context, CurContext, variance, varianceLoc,
766  index, paramLoc, paramName, colonLoc,
767  typeBoundInfo);
768 }
769 
771  SourceLocation lAngleLoc,
772  ArrayRef<Decl *> typeParamsIn,
773  SourceLocation rAngleLoc) {
774  // We know that the array only contains Objective-C type parameters.
776  typeParams(
777  reinterpret_cast<ObjCTypeParamDecl * const *>(typeParamsIn.data()),
778  typeParamsIn.size());
779 
780  // Diagnose redeclarations of type parameters.
781  // We do this now because Objective-C type parameters aren't pushed into
782  // scope until later (after the instance variable block), but we want the
783  // diagnostics to occur right after we parse the type parameter list.
784  llvm::SmallDenseMap<IdentifierInfo *, ObjCTypeParamDecl *> knownParams;
785  for (auto typeParam : typeParams) {
786  auto known = knownParams.find(typeParam->getIdentifier());
787  if (known != knownParams.end()) {
788  Diag(typeParam->getLocation(), diag::err_objc_type_param_redecl)
789  << typeParam->getIdentifier()
790  << SourceRange(known->second->getLocation());
791 
792  typeParam->setInvalidDecl();
793  } else {
794  knownParams.insert(std::make_pair(typeParam->getIdentifier(), typeParam));
795 
796  // Push the type parameter into scope.
797  PushOnScopeChains(typeParam, S, /*AddToContext=*/false);
798  }
799  }
800 
801  // Create the parameter list.
802  return ObjCTypeParamList::create(Context, lAngleLoc, typeParams, rAngleLoc);
803 }
804 
806  for (auto typeParam : *typeParamList) {
807  if (!typeParam->isInvalidDecl()) {
808  S->RemoveDecl(typeParam);
809  IdResolver.RemoveDecl(typeParam);
810  }
811  }
812 }
813 
814 namespace {
815  /// The context in which an Objective-C type parameter list occurs, for use
816  /// in diagnostics.
817  enum class TypeParamListContext {
818  ForwardDeclaration,
819  Definition,
820  Category,
821  Extension
822  };
823 } // end anonymous namespace
824 
825 /// Check consistency between two Objective-C type parameter lists, e.g.,
826 /// between a category/extension and an \@interface or between an \@class and an
827 /// \@interface.
829  ObjCTypeParamList *prevTypeParams,
830  ObjCTypeParamList *newTypeParams,
831  TypeParamListContext newContext) {
832  // If the sizes don't match, complain about that.
833  if (prevTypeParams->size() != newTypeParams->size()) {
834  SourceLocation diagLoc;
835  if (newTypeParams->size() > prevTypeParams->size()) {
836  diagLoc = newTypeParams->begin()[prevTypeParams->size()]->getLocation();
837  } else {
838  diagLoc = S.getLocForEndOfToken(newTypeParams->back()->getEndLoc());
839  }
840 
841  S.Diag(diagLoc, diag::err_objc_type_param_arity_mismatch)
842  << static_cast<unsigned>(newContext)
843  << (newTypeParams->size() > prevTypeParams->size())
844  << prevTypeParams->size()
845  << newTypeParams->size();
846 
847  return true;
848  }
849 
850  // Match up the type parameters.
851  for (unsigned i = 0, n = prevTypeParams->size(); i != n; ++i) {
852  ObjCTypeParamDecl *prevTypeParam = prevTypeParams->begin()[i];
853  ObjCTypeParamDecl *newTypeParam = newTypeParams->begin()[i];
854 
855  // Check for consistency of the variance.
856  if (newTypeParam->getVariance() != prevTypeParam->getVariance()) {
857  if (newTypeParam->getVariance() == ObjCTypeParamVariance::Invariant &&
858  newContext != TypeParamListContext::Definition) {
859  // When the new type parameter is invariant and is not part
860  // of the definition, just propagate the variance.
861  newTypeParam->setVariance(prevTypeParam->getVariance());
862  } else if (prevTypeParam->getVariance()
864  !(isa<ObjCInterfaceDecl>(prevTypeParam->getDeclContext()) &&
865  cast<ObjCInterfaceDecl>(prevTypeParam->getDeclContext())
866  ->getDefinition() == prevTypeParam->getDeclContext())) {
867  // When the old parameter is invariant and was not part of the
868  // definition, just ignore the difference because it doesn't
869  // matter.
870  } else {
871  {
872  // Diagnose the conflict and update the second declaration.
873  SourceLocation diagLoc = newTypeParam->getVarianceLoc();
874  if (diagLoc.isInvalid())
875  diagLoc = newTypeParam->getBeginLoc();
876 
877  auto diag = S.Diag(diagLoc,
878  diag::err_objc_type_param_variance_conflict)
879  << static_cast<unsigned>(newTypeParam->getVariance())
880  << newTypeParam->getDeclName()
881  << static_cast<unsigned>(prevTypeParam->getVariance())
882  << prevTypeParam->getDeclName();
883  switch (prevTypeParam->getVariance()) {
885  diag << FixItHint::CreateRemoval(newTypeParam->getVarianceLoc());
886  break;
887 
890  StringRef newVarianceStr
891  = prevTypeParam->getVariance() == ObjCTypeParamVariance::Covariant
892  ? "__covariant"
893  : "__contravariant";
894  if (newTypeParam->getVariance()
896  diag << FixItHint::CreateInsertion(newTypeParam->getBeginLoc(),
897  (newVarianceStr + " ").str());
898  } else {
899  diag << FixItHint::CreateReplacement(newTypeParam->getVarianceLoc(),
900  newVarianceStr);
901  }
902  }
903  }
904  }
905 
906  S.Diag(prevTypeParam->getLocation(), diag::note_objc_type_param_here)
907  << prevTypeParam->getDeclName();
908 
909  // Override the variance.
910  newTypeParam->setVariance(prevTypeParam->getVariance());
911  }
912  }
913 
914  // If the bound types match, there's nothing to do.
915  if (S.Context.hasSameType(prevTypeParam->getUnderlyingType(),
916  newTypeParam->getUnderlyingType()))
917  continue;
918 
919  // If the new type parameter's bound was explicit, complain about it being
920  // different from the original.
921  if (newTypeParam->hasExplicitBound()) {
922  SourceRange newBoundRange = newTypeParam->getTypeSourceInfo()
924  S.Diag(newBoundRange.getBegin(), diag::err_objc_type_param_bound_conflict)
925  << newTypeParam->getUnderlyingType()
926  << newTypeParam->getDeclName()
927  << prevTypeParam->hasExplicitBound()
928  << prevTypeParam->getUnderlyingType()
929  << (newTypeParam->getDeclName() == prevTypeParam->getDeclName())
930  << prevTypeParam->getDeclName()
932  newBoundRange,
933  prevTypeParam->getUnderlyingType().getAsString(
935 
936  S.Diag(prevTypeParam->getLocation(), diag::note_objc_type_param_here)
937  << prevTypeParam->getDeclName();
938 
939  // Override the new type parameter's bound type with the previous type,
940  // so that it's consistent.
941  S.Context.adjustObjCTypeParamBoundType(prevTypeParam, newTypeParam);
942  continue;
943  }
944 
945  // The new type parameter got the implicit bound of 'id'. That's okay for
946  // categories and extensions (overwrite it later), but not for forward
947  // declarations and @interfaces, because those must be standalone.
948  if (newContext == TypeParamListContext::ForwardDeclaration ||
949  newContext == TypeParamListContext::Definition) {
950  // Diagnose this problem for forward declarations and definitions.
951  SourceLocation insertionLoc
952  = S.getLocForEndOfToken(newTypeParam->getLocation());
953  std::string newCode
954  = " : " + prevTypeParam->getUnderlyingType().getAsString(
956  S.Diag(newTypeParam->getLocation(),
957  diag::err_objc_type_param_bound_missing)
958  << prevTypeParam->getUnderlyingType()
959  << newTypeParam->getDeclName()
960  << (newContext == TypeParamListContext::ForwardDeclaration)
961  << FixItHint::CreateInsertion(insertionLoc, newCode);
962 
963  S.Diag(prevTypeParam->getLocation(), diag::note_objc_type_param_here)
964  << prevTypeParam->getDeclName();
965  }
966 
967  // Update the new type parameter's bound to match the previous one.
968  S.Context.adjustObjCTypeParamBoundType(prevTypeParam, newTypeParam);
969  }
970 
971  return false;
972 }
973 
975  Scope *S, SourceLocation AtInterfaceLoc, IdentifierInfo *ClassName,
976  SourceLocation ClassLoc, ObjCTypeParamList *typeParamList,
977  IdentifierInfo *SuperName, SourceLocation SuperLoc,
978  ArrayRef<ParsedType> SuperTypeArgs, SourceRange SuperTypeArgsRange,
979  Decl *const *ProtoRefs, unsigned NumProtoRefs,
980  const SourceLocation *ProtoLocs, SourceLocation EndProtoLoc,
981  const ParsedAttributesView &AttrList) {
982  assert(ClassName && "Missing class identifier");
983 
984  // Check for another declaration kind with the same name.
985  NamedDecl *PrevDecl =
986  LookupSingleName(TUScope, ClassName, ClassLoc, LookupOrdinaryName,
988 
989  if (PrevDecl && !isa<ObjCInterfaceDecl>(PrevDecl)) {
990  Diag(ClassLoc, diag::err_redefinition_different_kind) << ClassName;
991  Diag(PrevDecl->getLocation(), diag::note_previous_definition);
992  }
993 
994  // Create a declaration to describe this @interface.
995  ObjCInterfaceDecl* PrevIDecl = dyn_cast_or_null<ObjCInterfaceDecl>(PrevDecl);
996 
997  if (PrevIDecl && PrevIDecl->getIdentifier() != ClassName) {
998  // A previous decl with a different name is because of
999  // @compatibility_alias, for example:
1000  // \code
1001  // @class NewImage;
1002  // @compatibility_alias OldImage NewImage;
1003  // \endcode
1004  // A lookup for 'OldImage' will return the 'NewImage' decl.
1005  //
1006  // In such a case use the real declaration name, instead of the alias one,
1007  // otherwise we will break IdentifierResolver and redecls-chain invariants.
1008  // FIXME: If necessary, add a bit to indicate that this ObjCInterfaceDecl
1009  // has been aliased.
1010  ClassName = PrevIDecl->getIdentifier();
1011  }
1012 
1013  // If there was a forward declaration with type parameters, check
1014  // for consistency.
1015  if (PrevIDecl) {
1016  if (ObjCTypeParamList *prevTypeParamList = PrevIDecl->getTypeParamList()) {
1017  if (typeParamList) {
1018  // Both have type parameter lists; check for consistency.
1019  if (checkTypeParamListConsistency(*this, prevTypeParamList,
1020  typeParamList,
1022  typeParamList = nullptr;
1023  }
1024  } else {
1025  Diag(ClassLoc, diag::err_objc_parameterized_forward_class_first)
1026  << ClassName;
1027  Diag(prevTypeParamList->getLAngleLoc(), diag::note_previous_decl)
1028  << ClassName;
1029 
1030  // Clone the type parameter list.
1031  SmallVector<ObjCTypeParamDecl *, 4> clonedTypeParams;
1032  for (auto typeParam : *prevTypeParamList) {
1033  clonedTypeParams.push_back(
1035  Context,
1036  CurContext,
1037  typeParam->getVariance(),
1038  SourceLocation(),
1039  typeParam->getIndex(),
1040  SourceLocation(),
1041  typeParam->getIdentifier(),
1042  SourceLocation(),
1043  Context.getTrivialTypeSourceInfo(typeParam->getUnderlyingType())));
1044  }
1045 
1046  typeParamList = ObjCTypeParamList::create(Context,
1047  SourceLocation(),
1048  clonedTypeParams,
1049  SourceLocation());
1050  }
1051  }
1052  }
1053 
1054  ObjCInterfaceDecl *IDecl
1055  = ObjCInterfaceDecl::Create(Context, CurContext, AtInterfaceLoc, ClassName,
1056  typeParamList, PrevIDecl, ClassLoc);
1057  if (PrevIDecl) {
1058  // Class already seen. Was it a definition?
1059  if (ObjCInterfaceDecl *Def = PrevIDecl->getDefinition()) {
1060  Diag(AtInterfaceLoc, diag::err_duplicate_class_def)
1061  << PrevIDecl->getDeclName();
1062  Diag(Def->getLocation(), diag::note_previous_definition);
1063  IDecl->setInvalidDecl();
1064  }
1065  }
1066 
1067  ProcessDeclAttributeList(TUScope, IDecl, AttrList);
1068  AddPragmaAttributes(TUScope, IDecl);
1069 
1070  // Merge attributes from previous declarations.
1071  if (PrevIDecl)
1072  mergeDeclAttributes(IDecl, PrevIDecl);
1073 
1074  PushOnScopeChains(IDecl, TUScope);
1075 
1076  // Start the definition of this class. If we're in a redefinition case, there
1077  // may already be a definition, so we'll end up adding to it.
1078  if (!IDecl->hasDefinition())
1079  IDecl->startDefinition();
1080 
1081  if (SuperName) {
1082  // Diagnose availability in the context of the @interface.
1083  ContextRAII SavedContext(*this, IDecl);
1084 
1085  ActOnSuperClassOfClassInterface(S, AtInterfaceLoc, IDecl,
1086  ClassName, ClassLoc,
1087  SuperName, SuperLoc, SuperTypeArgs,
1088  SuperTypeArgsRange);
1089  } else { // we have a root class.
1090  IDecl->setEndOfDefinitionLoc(ClassLoc);
1091  }
1092 
1093  // Check then save referenced protocols.
1094  if (NumProtoRefs) {
1095  diagnoseUseOfProtocols(*this, IDecl, (ObjCProtocolDecl*const*)ProtoRefs,
1096  NumProtoRefs, ProtoLocs);
1097  IDecl->setProtocolList((ObjCProtocolDecl*const*)ProtoRefs, NumProtoRefs,
1098  ProtoLocs, Context);
1099  IDecl->setEndOfDefinitionLoc(EndProtoLoc);
1100  }
1101 
1102  CheckObjCDeclScope(IDecl);
1103  return ActOnObjCContainerStartDefinition(IDecl);
1104 }
1105 
1106 /// ActOnTypedefedProtocols - this action finds protocol list as part of the
1107 /// typedef'ed use for a qualified super class and adds them to the list
1108 /// of the protocols.
1110  SmallVectorImpl<SourceLocation> &ProtocolLocs,
1111  IdentifierInfo *SuperName,
1112  SourceLocation SuperLoc) {
1113  if (!SuperName)
1114  return;
1115  NamedDecl* IDecl = LookupSingleName(TUScope, SuperName, SuperLoc,
1117  if (!IDecl)
1118  return;
1119 
1120  if (const TypedefNameDecl *TDecl = dyn_cast_or_null<TypedefNameDecl>(IDecl)) {
1121  QualType T = TDecl->getUnderlyingType();
1122  if (T->isObjCObjectType())
1123  if (const ObjCObjectType *OPT = T->getAs<ObjCObjectType>()) {
1124  ProtocolRefs.append(OPT->qual_begin(), OPT->qual_end());
1125  // FIXME: Consider whether this should be an invalid loc since the loc
1126  // is not actually pointing to a protocol name reference but to the
1127  // typedef reference. Note that the base class name loc is also pointing
1128  // at the typedef.
1129  ProtocolLocs.append(OPT->getNumProtocols(), SuperLoc);
1130  }
1131  }
1132 }
1133 
1134 /// ActOnCompatibilityAlias - this action is called after complete parsing of
1135 /// a \@compatibility_alias declaration. It sets up the alias relationships.
1137  IdentifierInfo *AliasName,
1138  SourceLocation AliasLocation,
1139  IdentifierInfo *ClassName,
1140  SourceLocation ClassLocation) {
1141  // Look for previous declaration of alias name
1142  NamedDecl *ADecl =
1143  LookupSingleName(TUScope, AliasName, AliasLocation, LookupOrdinaryName,
1145  if (ADecl) {
1146  Diag(AliasLocation, diag::err_conflicting_aliasing_type) << AliasName;
1147  Diag(ADecl->getLocation(), diag::note_previous_declaration);
1148  return nullptr;
1149  }
1150  // Check for class declaration
1151  NamedDecl *CDeclU =
1152  LookupSingleName(TUScope, ClassName, ClassLocation, LookupOrdinaryName,
1154  if (const TypedefNameDecl *TDecl =
1155  dyn_cast_or_null<TypedefNameDecl>(CDeclU)) {
1156  QualType T = TDecl->getUnderlyingType();
1157  if (T->isObjCObjectType()) {
1158  if (NamedDecl *IDecl = T->castAs<ObjCObjectType>()->getInterface()) {
1159  ClassName = IDecl->getIdentifier();
1160  CDeclU = LookupSingleName(TUScope, ClassName, ClassLocation,
1163  }
1164  }
1165  }
1166  ObjCInterfaceDecl *CDecl = dyn_cast_or_null<ObjCInterfaceDecl>(CDeclU);
1167  if (!CDecl) {
1168  Diag(ClassLocation, diag::warn_undef_interface) << ClassName;
1169  if (CDeclU)
1170  Diag(CDeclU->getLocation(), diag::note_previous_declaration);
1171  return nullptr;
1172  }
1173 
1174  // Everything checked out, instantiate a new alias declaration AST.
1176  ObjCCompatibleAliasDecl::Create(Context, CurContext, AtLoc, AliasName, CDecl);
1177 
1180 
1181  return AliasDecl;
1182 }
1183 
1185  IdentifierInfo *PName,
1186  SourceLocation &Ploc, SourceLocation PrevLoc,
1187  const ObjCList<ObjCProtocolDecl> &PList) {
1188 
1189  bool res = false;
1191  E = PList.end(); I != E; ++I) {
1192  if (ObjCProtocolDecl *PDecl = LookupProtocol((*I)->getIdentifier(),
1193  Ploc)) {
1194  if (PDecl->getIdentifier() == PName) {
1195  Diag(Ploc, diag::err_protocol_has_circular_dependency);
1196  Diag(PrevLoc, diag::note_previous_definition);
1197  res = true;
1198  }
1199 
1200  if (!PDecl->hasDefinition())
1201  continue;
1202 
1204  PDecl->getLocation(), PDecl->getReferencedProtocols()))
1205  res = true;
1206  }
1207  }
1208  return res;
1209 }
1210 
1212  SourceLocation AtProtoInterfaceLoc, IdentifierInfo *ProtocolName,
1213  SourceLocation ProtocolLoc, Decl *const *ProtoRefs, unsigned NumProtoRefs,
1214  const SourceLocation *ProtoLocs, SourceLocation EndProtoLoc,
1215  const ParsedAttributesView &AttrList) {
1216  bool err = false;
1217  // FIXME: Deal with AttrList.
1218  assert(ProtocolName && "Missing protocol identifier");
1219  ObjCProtocolDecl *PrevDecl = LookupProtocol(ProtocolName, ProtocolLoc,
1221  ObjCProtocolDecl *PDecl = nullptr;
1222  if (ObjCProtocolDecl *Def = PrevDecl? PrevDecl->getDefinition() : nullptr) {
1223  // If we already have a definition, complain.
1224  Diag(ProtocolLoc, diag::warn_duplicate_protocol_def) << ProtocolName;
1225  Diag(Def->getLocation(), diag::note_previous_definition);
1226 
1227  // Create a new protocol that is completely distinct from previous
1228  // declarations, and do not make this protocol available for name lookup.
1229  // That way, we'll end up completely ignoring the duplicate.
1230  // FIXME: Can we turn this into an error?
1231  PDecl = ObjCProtocolDecl::Create(Context, CurContext, ProtocolName,
1232  ProtocolLoc, AtProtoInterfaceLoc,
1233  /*PrevDecl=*/nullptr);
1234 
1235  // If we are using modules, add the decl to the context in order to
1236  // serialize something meaningful.
1237  if (getLangOpts().Modules)
1238  PushOnScopeChains(PDecl, TUScope);
1239  PDecl->startDefinition();
1240  } else {
1241  if (PrevDecl) {
1242  // Check for circular dependencies among protocol declarations. This can
1243  // only happen if this protocol was forward-declared.
1245  PList.set((ObjCProtocolDecl *const*)ProtoRefs, NumProtoRefs, Context);
1247  ProtocolName, ProtocolLoc, PrevDecl->getLocation(), PList);
1248  }
1249 
1250  // Create the new declaration.
1251  PDecl = ObjCProtocolDecl::Create(Context, CurContext, ProtocolName,
1252  ProtocolLoc, AtProtoInterfaceLoc,
1253  /*PrevDecl=*/PrevDecl);
1254 
1255  PushOnScopeChains(PDecl, TUScope);
1256  PDecl->startDefinition();
1257  }
1258 
1259  ProcessDeclAttributeList(TUScope, PDecl, AttrList);
1260  AddPragmaAttributes(TUScope, PDecl);
1261 
1262  // Merge attributes from previous declarations.
1263  if (PrevDecl)
1264  mergeDeclAttributes(PDecl, PrevDecl);
1265 
1266  if (!err && NumProtoRefs ) {
1267  /// Check then save referenced protocols.
1268  diagnoseUseOfProtocols(*this, PDecl, (ObjCProtocolDecl*const*)ProtoRefs,
1269  NumProtoRefs, ProtoLocs);
1270  PDecl->setProtocolList((ObjCProtocolDecl*const*)ProtoRefs, NumProtoRefs,
1271  ProtoLocs, Context);
1272  }
1273 
1274  CheckObjCDeclScope(PDecl);
1275  return ActOnObjCContainerStartDefinition(PDecl);
1276 }
1277 
1279  ObjCProtocolDecl *&UndefinedProtocol) {
1280  if (!PDecl->hasDefinition() ||
1281  !PDecl->getDefinition()->isUnconditionallyVisible()) {
1282  UndefinedProtocol = PDecl;
1283  return true;
1284  }
1285 
1286  for (auto *PI : PDecl->protocols())
1287  if (NestedProtocolHasNoDefinition(PI, UndefinedProtocol)) {
1288  UndefinedProtocol = PI;
1289  return true;
1290  }
1291  return false;
1292 }
1293 
1294 /// FindProtocolDeclaration - This routine looks up protocols and
1295 /// issues an error if they are not declared. It returns list of
1296 /// protocol declarations in its 'Protocols' argument.
1297 void
1298 Sema::FindProtocolDeclaration(bool WarnOnDeclarations, bool ForObjCContainer,
1299  ArrayRef<IdentifierLocPair> ProtocolId,
1300  SmallVectorImpl<Decl *> &Protocols) {
1301  for (const IdentifierLocPair &Pair : ProtocolId) {
1302  ObjCProtocolDecl *PDecl = LookupProtocol(Pair.first, Pair.second);
1303  if (!PDecl) {
1305  TypoCorrection Corrected = CorrectTypo(
1306  DeclarationNameInfo(Pair.first, Pair.second), LookupObjCProtocolName,
1307  TUScope, nullptr, CCC, CTK_ErrorRecovery);
1308  if ((PDecl = Corrected.getCorrectionDeclAs<ObjCProtocolDecl>()))
1309  diagnoseTypo(Corrected, PDiag(diag::err_undeclared_protocol_suggest)
1310  << Pair.first);
1311  }
1312 
1313  if (!PDecl) {
1314  Diag(Pair.second, diag::err_undeclared_protocol) << Pair.first;
1315  continue;
1316  }
1317  // If this is a forward protocol declaration, get its definition.
1318  if (!PDecl->isThisDeclarationADefinition() && PDecl->getDefinition())
1319  PDecl = PDecl->getDefinition();
1320 
1321  // For an objc container, delay protocol reference checking until after we
1322  // can set the objc decl as the availability context, otherwise check now.
1323  if (!ForObjCContainer) {
1324  (void)DiagnoseUseOfDecl(PDecl, Pair.second);
1325  }
1326 
1327  // If this is a forward declaration and we are supposed to warn in this
1328  // case, do it.
1329  // FIXME: Recover nicely in the hidden case.
1330  ObjCProtocolDecl *UndefinedProtocol;
1331 
1332  if (WarnOnDeclarations &&
1333  NestedProtocolHasNoDefinition(PDecl, UndefinedProtocol)) {
1334  Diag(Pair.second, diag::warn_undef_protocolref) << Pair.first;
1335  Diag(UndefinedProtocol->getLocation(), diag::note_protocol_decl_undefined)
1336  << UndefinedProtocol;
1337  }
1338  Protocols.push_back(PDecl);
1339  }
1340 }
1341 
1342 namespace {
1343 // Callback to only accept typo corrections that are either
1344 // Objective-C protocols or valid Objective-C type arguments.
1345 class ObjCTypeArgOrProtocolValidatorCCC final
1346  : public CorrectionCandidateCallback {
1347  ASTContext &Context;
1348  Sema::LookupNameKind LookupKind;
1349  public:
1350  ObjCTypeArgOrProtocolValidatorCCC(ASTContext &context,
1351  Sema::LookupNameKind lookupKind)
1352  : Context(context), LookupKind(lookupKind) { }
1353 
1354  bool ValidateCandidate(const TypoCorrection &candidate) override {
1355  // If we're allowed to find protocols and we have a protocol, accept it.
1356  if (LookupKind != Sema::LookupOrdinaryName) {
1357  if (candidate.getCorrectionDeclAs<ObjCProtocolDecl>())
1358  return true;
1359  }
1360 
1361  // If we're allowed to find type names and we have one, accept it.
1362  if (LookupKind != Sema::LookupObjCProtocolName) {
1363  // If we have a type declaration, we might accept this result.
1364  if (auto typeDecl = candidate.getCorrectionDeclAs<TypeDecl>()) {
1365  // If we found a tag declaration outside of C++, skip it. This
1366  // can happy because we look for any name when there is no
1367  // bias to protocol or type names.
1368  if (isa<RecordDecl>(typeDecl) && !Context.getLangOpts().CPlusPlus)
1369  return false;
1370 
1371  // Make sure the type is something we would accept as a type
1372  // argument.
1373  auto type = Context.getTypeDeclType(typeDecl);
1374  if (type->isObjCObjectPointerType() ||
1375  type->isBlockPointerType() ||
1376  type->isDependentType() ||
1377  type->isObjCObjectType())
1378  return true;
1379 
1380  return false;
1381  }
1382 
1383  // If we have an Objective-C class type, accept it; there will
1384  // be another fix to add the '*'.
1385  if (candidate.getCorrectionDeclAs<ObjCInterfaceDecl>())
1386  return true;
1387 
1388  return false;
1389  }
1390 
1391  return false;
1392  }
1393 
1394  std::unique_ptr<CorrectionCandidateCallback> clone() override {
1395  return std::make_unique<ObjCTypeArgOrProtocolValidatorCCC>(*this);
1396  }
1397 };
1398 } // end anonymous namespace
1399 
1401  SourceLocation ProtocolLoc,
1402  IdentifierInfo *TypeArgId,
1403  SourceLocation TypeArgLoc,
1404  bool SelectProtocolFirst) {
1405  Diag(TypeArgLoc, diag::err_objc_type_args_and_protocols)
1406  << SelectProtocolFirst << TypeArgId << ProtocolId
1407  << SourceRange(ProtocolLoc);
1408 }
1409 
1411  Scope *S,
1412  ParsedType baseType,
1413  SourceLocation lAngleLoc,
1414  ArrayRef<IdentifierInfo *> identifiers,
1415  ArrayRef<SourceLocation> identifierLocs,
1416  SourceLocation rAngleLoc,
1417  SourceLocation &typeArgsLAngleLoc,
1418  SmallVectorImpl<ParsedType> &typeArgs,
1419  SourceLocation &typeArgsRAngleLoc,
1420  SourceLocation &protocolLAngleLoc,
1421  SmallVectorImpl<Decl *> &protocols,
1422  SourceLocation &protocolRAngleLoc,
1423  bool warnOnIncompleteProtocols) {
1424  // Local function that updates the declaration specifiers with
1425  // protocol information.
1426  unsigned numProtocolsResolved = 0;
1427  auto resolvedAsProtocols = [&] {
1428  assert(numProtocolsResolved == identifiers.size() && "Unresolved protocols");
1429 
1430  // Determine whether the base type is a parameterized class, in
1431  // which case we want to warn about typos such as
1432  // "NSArray<NSObject>" (that should be NSArray<NSObject *>).
1433  ObjCInterfaceDecl *baseClass = nullptr;
1434  QualType base = GetTypeFromParser(baseType, nullptr);
1435  bool allAreTypeNames = false;
1436  SourceLocation firstClassNameLoc;
1437  if (!base.isNull()) {
1438  if (const auto *objcObjectType = base->getAs<ObjCObjectType>()) {
1439  baseClass = objcObjectType->getInterface();
1440  if (baseClass) {
1441  if (auto typeParams = baseClass->getTypeParamList()) {
1442  if (typeParams->size() == numProtocolsResolved) {
1443  // Note that we should be looking for type names, too.
1444  allAreTypeNames = true;
1445  }
1446  }
1447  }
1448  }
1449  }
1450 
1451  for (unsigned i = 0, n = protocols.size(); i != n; ++i) {
1452  ObjCProtocolDecl *&proto
1453  = reinterpret_cast<ObjCProtocolDecl *&>(protocols[i]);
1454  // For an objc container, delay protocol reference checking until after we
1455  // can set the objc decl as the availability context, otherwise check now.
1456  if (!warnOnIncompleteProtocols) {
1457  (void)DiagnoseUseOfDecl(proto, identifierLocs[i]);
1458  }
1459 
1460  // If this is a forward protocol declaration, get its definition.
1461  if (!proto->isThisDeclarationADefinition() && proto->getDefinition())
1462  proto = proto->getDefinition();
1463 
1464  // If this is a forward declaration and we are supposed to warn in this
1465  // case, do it.
1466  // FIXME: Recover nicely in the hidden case.
1467  ObjCProtocolDecl *forwardDecl = nullptr;
1468  if (warnOnIncompleteProtocols &&
1469  NestedProtocolHasNoDefinition(proto, forwardDecl)) {
1470  Diag(identifierLocs[i], diag::warn_undef_protocolref)
1471  << proto->getDeclName();
1472  Diag(forwardDecl->getLocation(), diag::note_protocol_decl_undefined)
1473  << forwardDecl;
1474  }
1475 
1476  // If everything this far has been a type name (and we care
1477  // about such things), check whether this name refers to a type
1478  // as well.
1479  if (allAreTypeNames) {
1480  if (auto *decl = LookupSingleName(S, identifiers[i], identifierLocs[i],
1481  LookupOrdinaryName)) {
1482  if (isa<ObjCInterfaceDecl>(decl)) {
1483  if (firstClassNameLoc.isInvalid())
1484  firstClassNameLoc = identifierLocs[i];
1485  } else if (!isa<TypeDecl>(decl)) {
1486  // Not a type.
1487  allAreTypeNames = false;
1488  }
1489  } else {
1490  allAreTypeNames = false;
1491  }
1492  }
1493  }
1494 
1495  // All of the protocols listed also have type names, and at least
1496  // one is an Objective-C class name. Check whether all of the
1497  // protocol conformances are declared by the base class itself, in
1498  // which case we warn.
1499  if (allAreTypeNames && firstClassNameLoc.isValid()) {
1501  Context.CollectInheritedProtocols(baseClass, knownProtocols);
1502  bool allProtocolsDeclared = true;
1503  for (auto proto : protocols) {
1504  if (knownProtocols.count(static_cast<ObjCProtocolDecl *>(proto)) == 0) {
1505  allProtocolsDeclared = false;
1506  break;
1507  }
1508  }
1509 
1510  if (allProtocolsDeclared) {
1511  Diag(firstClassNameLoc, diag::warn_objc_redundant_qualified_class_type)
1512  << baseClass->getDeclName() << SourceRange(lAngleLoc, rAngleLoc)
1513  << FixItHint::CreateInsertion(getLocForEndOfToken(firstClassNameLoc),
1514  " *");
1515  }
1516  }
1517 
1518  protocolLAngleLoc = lAngleLoc;
1519  protocolRAngleLoc = rAngleLoc;
1520  assert(protocols.size() == identifierLocs.size());
1521  };
1522 
1523  // Attempt to resolve all of the identifiers as protocols.
1524  for (unsigned i = 0, n = identifiers.size(); i != n; ++i) {
1525  ObjCProtocolDecl *proto = LookupProtocol(identifiers[i], identifierLocs[i]);
1526  protocols.push_back(proto);
1527  if (proto)
1528  ++numProtocolsResolved;
1529  }
1530 
1531  // If all of the names were protocols, these were protocol qualifiers.
1532  if (numProtocolsResolved == identifiers.size())
1533  return resolvedAsProtocols();
1534 
1535  // Attempt to resolve all of the identifiers as type names or
1536  // Objective-C class names. The latter is technically ill-formed,
1537  // but is probably something like \c NSArray<NSView *> missing the
1538  // \c*.
1539  typedef llvm::PointerUnion<TypeDecl *, ObjCInterfaceDecl *> TypeOrClassDecl;
1541  unsigned numTypeDeclsResolved = 0;
1542  for (unsigned i = 0, n = identifiers.size(); i != n; ++i) {
1543  NamedDecl *decl = LookupSingleName(S, identifiers[i], identifierLocs[i],
1545  if (!decl) {
1546  typeDecls.push_back(TypeOrClassDecl());
1547  continue;
1548  }
1549 
1550  if (auto typeDecl = dyn_cast<TypeDecl>(decl)) {
1551  typeDecls.push_back(typeDecl);
1552  ++numTypeDeclsResolved;
1553  continue;
1554  }
1555 
1556  if (auto objcClass = dyn_cast<ObjCInterfaceDecl>(decl)) {
1557  typeDecls.push_back(objcClass);
1558  ++numTypeDeclsResolved;
1559  continue;
1560  }
1561 
1562  typeDecls.push_back(TypeOrClassDecl());
1563  }
1564 
1565  AttributeFactory attrFactory;
1566 
1567  // Local function that forms a reference to the given type or
1568  // Objective-C class declaration.
1569  auto resolveTypeReference = [&](TypeOrClassDecl typeDecl, SourceLocation loc)
1570  -> TypeResult {
1571  // Form declaration specifiers. They simply refer to the type.
1572  DeclSpec DS(attrFactory);
1573  const char* prevSpec; // unused
1574  unsigned diagID; // unused
1575  QualType type;
1576  if (auto *actualTypeDecl = typeDecl.dyn_cast<TypeDecl *>())
1577  type = Context.getTypeDeclType(actualTypeDecl);
1578  else
1579  type = Context.getObjCInterfaceType(typeDecl.get<ObjCInterfaceDecl *>());
1580  TypeSourceInfo *parsedTSInfo = Context.getTrivialTypeSourceInfo(type, loc);
1581  ParsedType parsedType = CreateParsedType(type, parsedTSInfo);
1582  DS.SetTypeSpecType(DeclSpec::TST_typename, loc, prevSpec, diagID,
1583  parsedType, Context.getPrintingPolicy());
1584  // Use the identifier location for the type source range.
1585  DS.SetRangeStart(loc);
1586  DS.SetRangeEnd(loc);
1587 
1588  // Form the declarator.
1590 
1591  // If we have a typedef of an Objective-C class type that is missing a '*',
1592  // add the '*'.
1593  if (type->getAs<ObjCInterfaceType>()) {
1594  SourceLocation starLoc = getLocForEndOfToken(loc);
1595  D.AddTypeInfo(DeclaratorChunk::getPointer(/*TypeQuals=*/0, starLoc,
1596  SourceLocation(),
1597  SourceLocation(),
1598  SourceLocation(),
1599  SourceLocation(),
1600  SourceLocation()),
1601  starLoc);
1602 
1603  // Diagnose the missing '*'.
1604  Diag(loc, diag::err_objc_type_arg_missing_star)
1605  << type
1606  << FixItHint::CreateInsertion(starLoc, " *");
1607  }
1608 
1609  // Convert this to a type.
1610  return ActOnTypeName(S, D);
1611  };
1612 
1613  // Local function that updates the declaration specifiers with
1614  // type argument information.
1615  auto resolvedAsTypeDecls = [&] {
1616  // We did not resolve these as protocols.
1617  protocols.clear();
1618 
1619  assert(numTypeDeclsResolved == identifiers.size() && "Unresolved type decl");
1620  // Map type declarations to type arguments.
1621  for (unsigned i = 0, n = identifiers.size(); i != n; ++i) {
1622  // Map type reference to a type.
1623  TypeResult type = resolveTypeReference(typeDecls[i], identifierLocs[i]);
1624  if (!type.isUsable()) {
1625  typeArgs.clear();
1626  return;
1627  }
1628 
1629  typeArgs.push_back(type.get());
1630  }
1631 
1632  typeArgsLAngleLoc = lAngleLoc;
1633  typeArgsRAngleLoc = rAngleLoc;
1634  };
1635 
1636  // If all of the identifiers can be resolved as type names or
1637  // Objective-C class names, we have type arguments.
1638  if (numTypeDeclsResolved == identifiers.size())
1639  return resolvedAsTypeDecls();
1640 
1641  // Error recovery: some names weren't found, or we have a mix of
1642  // type and protocol names. Go resolve all of the unresolved names
1643  // and complain if we can't find a consistent answer.
1644  LookupNameKind lookupKind = LookupAnyName;
1645  for (unsigned i = 0, n = identifiers.size(); i != n; ++i) {
1646  // If we already have a protocol or type. Check whether it is the
1647  // right thing.
1648  if (protocols[i] || typeDecls[i]) {
1649  // If we haven't figured out whether we want types or protocols
1650  // yet, try to figure it out from this name.
1651  if (lookupKind == LookupAnyName) {
1652  // If this name refers to both a protocol and a type (e.g., \c
1653  // NSObject), don't conclude anything yet.
1654  if (protocols[i] && typeDecls[i])
1655  continue;
1656 
1657  // Otherwise, let this name decide whether we'll be correcting
1658  // toward types or protocols.
1659  lookupKind = protocols[i] ? LookupObjCProtocolName
1661  continue;
1662  }
1663 
1664  // If we want protocols and we have a protocol, there's nothing
1665  // more to do.
1666  if (lookupKind == LookupObjCProtocolName && protocols[i])
1667  continue;
1668 
1669  // If we want types and we have a type declaration, there's
1670  // nothing more to do.
1671  if (lookupKind == LookupOrdinaryName && typeDecls[i])
1672  continue;
1673 
1674  // We have a conflict: some names refer to protocols and others
1675  // refer to types.
1676  DiagnoseTypeArgsAndProtocols(identifiers[0], identifierLocs[0],
1677  identifiers[i], identifierLocs[i],
1678  protocols[i] != nullptr);
1679 
1680  protocols.clear();
1681  typeArgs.clear();
1682  return;
1683  }
1684 
1685  // Perform typo correction on the name.
1686  ObjCTypeArgOrProtocolValidatorCCC CCC(Context, lookupKind);
1687  TypoCorrection corrected =
1688  CorrectTypo(DeclarationNameInfo(identifiers[i], identifierLocs[i]),
1689  lookupKind, S, nullptr, CCC, CTK_ErrorRecovery);
1690  if (corrected) {
1691  // Did we find a protocol?
1692  if (auto proto = corrected.getCorrectionDeclAs<ObjCProtocolDecl>()) {
1693  diagnoseTypo(corrected,
1694  PDiag(diag::err_undeclared_protocol_suggest)
1695  << identifiers[i]);
1696  lookupKind = LookupObjCProtocolName;
1697  protocols[i] = proto;
1698  ++numProtocolsResolved;
1699  continue;
1700  }
1701 
1702  // Did we find a type?
1703  if (auto typeDecl = corrected.getCorrectionDeclAs<TypeDecl>()) {
1704  diagnoseTypo(corrected,
1705  PDiag(diag::err_unknown_typename_suggest)
1706  << identifiers[i]);
1707  lookupKind = LookupOrdinaryName;
1708  typeDecls[i] = typeDecl;
1709  ++numTypeDeclsResolved;
1710  continue;
1711  }
1712 
1713  // Did we find an Objective-C class?
1714  if (auto objcClass = corrected.getCorrectionDeclAs<ObjCInterfaceDecl>()) {
1715  diagnoseTypo(corrected,
1716  PDiag(diag::err_unknown_type_or_class_name_suggest)
1717  << identifiers[i] << true);
1718  lookupKind = LookupOrdinaryName;
1719  typeDecls[i] = objcClass;
1720  ++numTypeDeclsResolved;
1721  continue;
1722  }
1723  }
1724 
1725  // We couldn't find anything.
1726  Diag(identifierLocs[i],
1727  (lookupKind == LookupAnyName ? diag::err_objc_type_arg_missing
1728  : lookupKind == LookupObjCProtocolName ? diag::err_undeclared_protocol
1729  : diag::err_unknown_typename))
1730  << identifiers[i];
1731  protocols.clear();
1732  typeArgs.clear();
1733  return;
1734  }
1735 
1736  // If all of the names were (corrected to) protocols, these were
1737  // protocol qualifiers.
1738  if (numProtocolsResolved == identifiers.size())
1739  return resolvedAsProtocols();
1740 
1741  // Otherwise, all of the names were (corrected to) types.
1742  assert(numTypeDeclsResolved == identifiers.size() && "Not all types?");
1743  return resolvedAsTypeDecls();
1744 }
1745 
1746 /// DiagnoseClassExtensionDupMethods - Check for duplicate declaration of
1747 /// a class method in its extension.
1748 ///
1750  ObjCInterfaceDecl *ID) {
1751  if (!ID)
1752  return; // Possibly due to previous error
1753 
1754  llvm::DenseMap<Selector, const ObjCMethodDecl*> MethodMap;
1755  for (auto *MD : ID->methods())
1756  MethodMap[MD->getSelector()] = MD;
1757 
1758  if (MethodMap.empty())
1759  return;
1760  for (const auto *Method : CAT->methods()) {
1761  const ObjCMethodDecl *&PrevMethod = MethodMap[Method->getSelector()];
1762  if (PrevMethod &&
1763  (PrevMethod->isInstanceMethod() == Method->isInstanceMethod()) &&
1764  !MatchTwoMethodDeclarations(Method, PrevMethod)) {
1765  Diag(Method->getLocation(), diag::err_duplicate_method_decl)
1766  << Method->getDeclName();
1767  Diag(PrevMethod->getLocation(), diag::note_previous_declaration);
1768  }
1769  }
1770 }
1771 
1772 /// ActOnForwardProtocolDeclaration - Handle \@protocol foo;
1775  ArrayRef<IdentifierLocPair> IdentList,
1776  const ParsedAttributesView &attrList) {
1777  SmallVector<Decl *, 8> DeclsInGroup;
1778  for (const IdentifierLocPair &IdentPair : IdentList) {
1779  IdentifierInfo *Ident = IdentPair.first;
1780  ObjCProtocolDecl *PrevDecl = LookupProtocol(Ident, IdentPair.second,
1782  ObjCProtocolDecl *PDecl
1784  IdentPair.second, AtProtocolLoc,
1785  PrevDecl);
1786 
1787  PushOnScopeChains(PDecl, TUScope);
1788  CheckObjCDeclScope(PDecl);
1789 
1790  ProcessDeclAttributeList(TUScope, PDecl, attrList);
1791  AddPragmaAttributes(TUScope, PDecl);
1792 
1793  if (PrevDecl)
1794  mergeDeclAttributes(PDecl, PrevDecl);
1795 
1796  DeclsInGroup.push_back(PDecl);
1797  }
1798 
1799  return BuildDeclaratorGroup(DeclsInGroup);
1800 }
1801 
1803  SourceLocation AtInterfaceLoc, IdentifierInfo *ClassName,
1804  SourceLocation ClassLoc, ObjCTypeParamList *typeParamList,
1805  IdentifierInfo *CategoryName, SourceLocation CategoryLoc,
1806  Decl *const *ProtoRefs, unsigned NumProtoRefs,
1807  const SourceLocation *ProtoLocs, SourceLocation EndProtoLoc,
1808  const ParsedAttributesView &AttrList) {
1809  ObjCCategoryDecl *CDecl;
1810  ObjCInterfaceDecl *IDecl = getObjCInterfaceDecl(ClassName, ClassLoc, true);
1811 
1812  /// Check that class of this category is already completely declared.
1813 
1814  if (!IDecl
1815  || RequireCompleteType(ClassLoc, Context.getObjCInterfaceType(IDecl),
1816  diag::err_category_forward_interface,
1817  CategoryName == nullptr)) {
1818  // Create an invalid ObjCCategoryDecl to serve as context for
1819  // the enclosing method declarations. We mark the decl invalid
1820  // to make it clear that this isn't a valid AST.
1821  CDecl = ObjCCategoryDecl::Create(Context, CurContext, AtInterfaceLoc,
1822  ClassLoc, CategoryLoc, CategoryName,
1823  IDecl, typeParamList);
1824  CDecl->setInvalidDecl();
1825  CurContext->addDecl(CDecl);
1826 
1827  if (!IDecl)
1828  Diag(ClassLoc, diag::err_undef_interface) << ClassName;
1829  return ActOnObjCContainerStartDefinition(CDecl);
1830  }
1831 
1832  if (!CategoryName && IDecl->getImplementation()) {
1833  Diag(ClassLoc, diag::err_class_extension_after_impl) << ClassName;
1834  Diag(IDecl->getImplementation()->getLocation(),
1835  diag::note_implementation_declared);
1836  }
1837 
1838  if (CategoryName) {
1839  /// Check for duplicate interface declaration for this category
1841  = IDecl->FindCategoryDeclaration(CategoryName)) {
1842  // Class extensions can be declared multiple times, categories cannot.
1843  Diag(CategoryLoc, diag::warn_dup_category_def)
1844  << ClassName << CategoryName;
1845  Diag(Previous->getLocation(), diag::note_previous_definition);
1846  }
1847  }
1848 
1849  // If we have a type parameter list, check it.
1850  if (typeParamList) {
1851  if (auto prevTypeParamList = IDecl->getTypeParamList()) {
1852  if (checkTypeParamListConsistency(*this, prevTypeParamList, typeParamList,
1853  CategoryName
1855  : TypeParamListContext::Extension))
1856  typeParamList = nullptr;
1857  } else {
1858  Diag(typeParamList->getLAngleLoc(),
1859  diag::err_objc_parameterized_category_nonclass)
1860  << (CategoryName != nullptr)
1861  << ClassName
1862  << typeParamList->getSourceRange();
1863 
1864  typeParamList = nullptr;
1865  }
1866  }
1867 
1868  CDecl = ObjCCategoryDecl::Create(Context, CurContext, AtInterfaceLoc,
1869  ClassLoc, CategoryLoc, CategoryName, IDecl,
1870  typeParamList);
1871  // FIXME: PushOnScopeChains?
1872  CurContext->addDecl(CDecl);
1873 
1874  // Process the attributes before looking at protocols to ensure that the
1875  // availability attribute is attached to the category to provide availability
1876  // checking for protocol uses.
1877  ProcessDeclAttributeList(TUScope, CDecl, AttrList);
1878  AddPragmaAttributes(TUScope, CDecl);
1879 
1880  if (NumProtoRefs) {
1881  diagnoseUseOfProtocols(*this, CDecl, (ObjCProtocolDecl*const*)ProtoRefs,
1882  NumProtoRefs, ProtoLocs);
1883  CDecl->setProtocolList((ObjCProtocolDecl*const*)ProtoRefs, NumProtoRefs,
1884  ProtoLocs, Context);
1885  // Protocols in the class extension belong to the class.
1886  if (CDecl->IsClassExtension())
1887  IDecl->mergeClassExtensionProtocolList((ObjCProtocolDecl*const*)ProtoRefs,
1888  NumProtoRefs, Context);
1889  }
1890 
1891  CheckObjCDeclScope(CDecl);
1892  return ActOnObjCContainerStartDefinition(CDecl);
1893 }
1894 
1895 /// ActOnStartCategoryImplementation - Perform semantic checks on the
1896 /// category implementation declaration and build an ObjCCategoryImplDecl
1897 /// object.
1899  SourceLocation AtCatImplLoc,
1900  IdentifierInfo *ClassName, SourceLocation ClassLoc,
1901  IdentifierInfo *CatName, SourceLocation CatLoc,
1902  const ParsedAttributesView &Attrs) {
1903  ObjCInterfaceDecl *IDecl = getObjCInterfaceDecl(ClassName, ClassLoc, true);
1904  ObjCCategoryDecl *CatIDecl = nullptr;
1905  if (IDecl && IDecl->hasDefinition()) {
1906  CatIDecl = IDecl->FindCategoryDeclaration(CatName);
1907  if (!CatIDecl) {
1908  // Category @implementation with no corresponding @interface.
1909  // Create and install one.
1910  CatIDecl = ObjCCategoryDecl::Create(Context, CurContext, AtCatImplLoc,
1911  ClassLoc, CatLoc,
1912  CatName, IDecl,
1913  /*typeParamList=*/nullptr);
1914  CatIDecl->setImplicit();
1915  }
1916  }
1917 
1918  ObjCCategoryImplDecl *CDecl =
1920  ClassLoc, AtCatImplLoc, CatLoc);
1921  /// Check that class of this category is already completely declared.
1922  if (!IDecl) {
1923  Diag(ClassLoc, diag::err_undef_interface) << ClassName;
1924  CDecl->setInvalidDecl();
1925  } else if (RequireCompleteType(ClassLoc, Context.getObjCInterfaceType(IDecl),
1926  diag::err_undef_interface)) {
1927  CDecl->setInvalidDecl();
1928  }
1929 
1930  ProcessDeclAttributeList(TUScope, CDecl, Attrs);
1931  AddPragmaAttributes(TUScope, CDecl);
1932 
1933  // FIXME: PushOnScopeChains?
1934  CurContext->addDecl(CDecl);
1935 
1936  // If the interface has the objc_runtime_visible attribute, we
1937  // cannot implement a category for it.
1938  if (IDecl && IDecl->hasAttr<ObjCRuntimeVisibleAttr>()) {
1939  Diag(ClassLoc, diag::err_objc_runtime_visible_category)
1940  << IDecl->getDeclName();
1941  }
1942 
1943  /// Check that CatName, category name, is not used in another implementation.
1944  if (CatIDecl) {
1945  if (CatIDecl->getImplementation()) {
1946  Diag(ClassLoc, diag::err_dup_implementation_category) << ClassName
1947  << CatName;
1948  Diag(CatIDecl->getImplementation()->getLocation(),
1949  diag::note_previous_definition);
1950  CDecl->setInvalidDecl();
1951  } else {
1952  CatIDecl->setImplementation(CDecl);
1953  // Warn on implementating category of deprecated class under
1954  // -Wdeprecated-implementations flag.
1955  DiagnoseObjCImplementedDeprecations(*this, CatIDecl,
1956  CDecl->getLocation());
1957  }
1958  }
1959 
1960  CheckObjCDeclScope(CDecl);
1961  return ActOnObjCContainerStartDefinition(CDecl);
1962 }
1963 
1965  SourceLocation AtClassImplLoc,
1966  IdentifierInfo *ClassName, SourceLocation ClassLoc,
1967  IdentifierInfo *SuperClassname,
1968  SourceLocation SuperClassLoc,
1969  const ParsedAttributesView &Attrs) {
1970  ObjCInterfaceDecl *IDecl = nullptr;
1971  // Check for another declaration kind with the same name.
1972  NamedDecl *PrevDecl
1973  = LookupSingleName(TUScope, ClassName, ClassLoc, LookupOrdinaryName,
1975  if (PrevDecl && !isa<ObjCInterfaceDecl>(PrevDecl)) {
1976  Diag(ClassLoc, diag::err_redefinition_different_kind) << ClassName;
1977  Diag(PrevDecl->getLocation(), diag::note_previous_definition);
1978  } else if ((IDecl = dyn_cast_or_null<ObjCInterfaceDecl>(PrevDecl))) {
1979  // FIXME: This will produce an error if the definition of the interface has
1980  // been imported from a module but is not visible.
1982  diag::warn_undef_interface);
1983  } else {
1984  // We did not find anything with the name ClassName; try to correct for
1985  // typos in the class name.
1986  ObjCInterfaceValidatorCCC CCC{};
1987  TypoCorrection Corrected =
1988  CorrectTypo(DeclarationNameInfo(ClassName, ClassLoc),
1989  LookupOrdinaryName, TUScope, nullptr, CCC, CTK_NonError);
1990  if (Corrected.getCorrectionDeclAs<ObjCInterfaceDecl>()) {
1991  // Suggest the (potentially) correct interface name. Don't provide a
1992  // code-modification hint or use the typo name for recovery, because
1993  // this is just a warning. The program may actually be correct.
1994  diagnoseTypo(Corrected,
1995  PDiag(diag::warn_undef_interface_suggest) << ClassName,
1996  /*ErrorRecovery*/false);
1997  } else {
1998  Diag(ClassLoc, diag::warn_undef_interface) << ClassName;
1999  }
2000  }
2001 
2002  // Check that super class name is valid class name
2003  ObjCInterfaceDecl *SDecl = nullptr;
2004  if (SuperClassname) {
2005  // Check if a different kind of symbol declared in this scope.
2006  PrevDecl = LookupSingleName(TUScope, SuperClassname, SuperClassLoc,
2008  if (PrevDecl && !isa<ObjCInterfaceDecl>(PrevDecl)) {
2009  Diag(SuperClassLoc, diag::err_redefinition_different_kind)
2010  << SuperClassname;
2011  Diag(PrevDecl->getLocation(), diag::note_previous_definition);
2012  } else {
2013  SDecl = dyn_cast_or_null<ObjCInterfaceDecl>(PrevDecl);
2014  if (SDecl && !SDecl->hasDefinition())
2015  SDecl = nullptr;
2016  if (!SDecl)
2017  Diag(SuperClassLoc, diag::err_undef_superclass)
2018  << SuperClassname << ClassName;
2019  else if (IDecl && !declaresSameEntity(IDecl->getSuperClass(), SDecl)) {
2020  // This implementation and its interface do not have the same
2021  // super class.
2022  Diag(SuperClassLoc, diag::err_conflicting_super_class)
2023  << SDecl->getDeclName();
2024  Diag(SDecl->getLocation(), diag::note_previous_definition);
2025  }
2026  }
2027  }
2028 
2029  if (!IDecl) {
2030  // Legacy case of @implementation with no corresponding @interface.
2031  // Build, chain & install the interface decl into the identifier.
2032 
2033  // FIXME: Do we support attributes on the @implementation? If so we should
2034  // copy them over.
2035  IDecl = ObjCInterfaceDecl::Create(Context, CurContext, AtClassImplLoc,
2036  ClassName, /*typeParamList=*/nullptr,
2037  /*PrevDecl=*/nullptr, ClassLoc,
2038  true);
2039  AddPragmaAttributes(TUScope, IDecl);
2040  IDecl->startDefinition();
2041  if (SDecl) {
2044  SuperClassLoc));
2045  IDecl->setEndOfDefinitionLoc(SuperClassLoc);
2046  } else {
2047  IDecl->setEndOfDefinitionLoc(ClassLoc);
2048  }
2049 
2050  PushOnScopeChains(IDecl, TUScope);
2051  } else {
2052  // Mark the interface as being completed, even if it was just as
2053  // @class ....;
2054  // declaration; the user cannot reopen it.
2055  if (!IDecl->hasDefinition())
2056  IDecl->startDefinition();
2057  }
2058 
2059  ObjCImplementationDecl* IMPDecl =
2061  ClassLoc, AtClassImplLoc, SuperClassLoc);
2062 
2063  ProcessDeclAttributeList(TUScope, IMPDecl, Attrs);
2064  AddPragmaAttributes(TUScope, IMPDecl);
2065 
2066  if (CheckObjCDeclScope(IMPDecl))
2067  return ActOnObjCContainerStartDefinition(IMPDecl);
2068 
2069  // Check that there is no duplicate implementation of this class.
2070  if (IDecl->getImplementation()) {
2071  // FIXME: Don't leak everything!
2072  Diag(ClassLoc, diag::err_dup_implementation_class) << ClassName;
2073  Diag(IDecl->getImplementation()->getLocation(),
2074  diag::note_previous_definition);
2075  IMPDecl->setInvalidDecl();
2076  } else { // add it to the list.
2077  IDecl->setImplementation(IMPDecl);
2078  PushOnScopeChains(IMPDecl, TUScope);
2079  // Warn on implementating deprecated class under
2080  // -Wdeprecated-implementations flag.
2081  DiagnoseObjCImplementedDeprecations(*this, IDecl, IMPDecl->getLocation());
2082  }
2083 
2084  // If the superclass has the objc_runtime_visible attribute, we
2085  // cannot implement a subclass of it.
2086  if (IDecl->getSuperClass() &&
2087  IDecl->getSuperClass()->hasAttr<ObjCRuntimeVisibleAttr>()) {
2088  Diag(ClassLoc, diag::err_objc_runtime_visible_subclass)
2089  << IDecl->getDeclName()
2090  << IDecl->getSuperClass()->getDeclName();
2091  }
2092 
2093  return ActOnObjCContainerStartDefinition(IMPDecl);
2094 }
2095 
2098  SmallVector<Decl *, 64> DeclsInGroup;
2099  DeclsInGroup.reserve(Decls.size() + 1);
2100 
2101  for (unsigned i = 0, e = Decls.size(); i != e; ++i) {
2102  Decl *Dcl = Decls[i];
2103  if (!Dcl)
2104  continue;
2105  if (Dcl->getDeclContext()->isFileContext())
2107  DeclsInGroup.push_back(Dcl);
2108  }
2109 
2110  DeclsInGroup.push_back(ObjCImpDecl);
2111 
2112  return BuildDeclaratorGroup(DeclsInGroup);
2113 }
2114 
2116  ObjCIvarDecl **ivars, unsigned numIvars,
2117  SourceLocation RBrace) {
2118  assert(ImpDecl && "missing implementation decl");
2119  ObjCInterfaceDecl* IDecl = ImpDecl->getClassInterface();
2120  if (!IDecl)
2121  return;
2122  /// Check case of non-existing \@interface decl.
2123  /// (legacy objective-c \@implementation decl without an \@interface decl).
2124  /// Add implementations's ivar to the synthesize class's ivar list.
2125  if (IDecl->isImplicitInterfaceDecl()) {
2126  IDecl->setEndOfDefinitionLoc(RBrace);
2127  // Add ivar's to class's DeclContext.
2128  for (unsigned i = 0, e = numIvars; i != e; ++i) {
2129  ivars[i]->setLexicalDeclContext(ImpDecl);
2130  // In a 'fragile' runtime the ivar was added to the implicit
2131  // ObjCInterfaceDecl while in a 'non-fragile' runtime the ivar is
2132  // only in the ObjCImplementationDecl. In the non-fragile case the ivar
2133  // therefore also needs to be propagated to the ObjCInterfaceDecl.
2135  IDecl->makeDeclVisibleInContext(ivars[i]);
2136  ImpDecl->addDecl(ivars[i]);
2137  }
2138 
2139  return;
2140  }
2141  // If implementation has empty ivar list, just return.
2142  if (numIvars == 0)
2143  return;
2144 
2145  assert(ivars && "missing @implementation ivars");
2147  if (ImpDecl->getSuperClass())
2148  Diag(ImpDecl->getLocation(), diag::warn_on_superclass_use);
2149  for (unsigned i = 0; i < numIvars; i++) {
2150  ObjCIvarDecl* ImplIvar = ivars[i];
2151  if (const ObjCIvarDecl *ClsIvar =
2152  IDecl->getIvarDecl(ImplIvar->getIdentifier())) {
2153  Diag(ImplIvar->getLocation(), diag::err_duplicate_ivar_declaration);
2154  Diag(ClsIvar->getLocation(), diag::note_previous_definition);
2155  continue;
2156  }
2157  // Check class extensions (unnamed categories) for duplicate ivars.
2158  for (const auto *CDecl : IDecl->visible_extensions()) {
2159  if (const ObjCIvarDecl *ClsExtIvar =
2160  CDecl->getIvarDecl(ImplIvar->getIdentifier())) {
2161  Diag(ImplIvar->getLocation(), diag::err_duplicate_ivar_declaration);
2162  Diag(ClsExtIvar->getLocation(), diag::note_previous_definition);
2163  continue;
2164  }
2165  }
2166  // Instance ivar to Implementation's DeclContext.
2167  ImplIvar->setLexicalDeclContext(ImpDecl);
2168  IDecl->makeDeclVisibleInContext(ImplIvar);
2169  ImpDecl->addDecl(ImplIvar);
2170  }
2171  return;
2172  }
2173  // Check interface's Ivar list against those in the implementation.
2174  // names and types must match.
2175  //
2176  unsigned j = 0;
2178  IVI = IDecl->ivar_begin(), IVE = IDecl->ivar_end();
2179  for (; numIvars > 0 && IVI != IVE; ++IVI) {
2180  ObjCIvarDecl* ImplIvar = ivars[j++];
2181  ObjCIvarDecl* ClsIvar = *IVI;
2182  assert (ImplIvar && "missing implementation ivar");
2183  assert (ClsIvar && "missing class ivar");
2184 
2185  // First, make sure the types match.
2186  if (!Context.hasSameType(ImplIvar->getType(), ClsIvar->getType())) {
2187  Diag(ImplIvar->getLocation(), diag::err_conflicting_ivar_type)
2188  << ImplIvar->getIdentifier()
2189  << ImplIvar->getType() << ClsIvar->getType();
2190  Diag(ClsIvar->getLocation(), diag::note_previous_definition);
2191  } else if (ImplIvar->isBitField() && ClsIvar->isBitField() &&
2192  ImplIvar->getBitWidthValue(Context) !=
2193  ClsIvar->getBitWidthValue(Context)) {
2194  Diag(ImplIvar->getBitWidth()->getBeginLoc(),
2195  diag::err_conflicting_ivar_bitwidth)
2196  << ImplIvar->getIdentifier();
2197  Diag(ClsIvar->getBitWidth()->getBeginLoc(),
2198  diag::note_previous_definition);
2199  }
2200  // Make sure the names are identical.
2201  if (ImplIvar->getIdentifier() != ClsIvar->getIdentifier()) {
2202  Diag(ImplIvar->getLocation(), diag::err_conflicting_ivar_name)
2203  << ImplIvar->getIdentifier() << ClsIvar->getIdentifier();
2204  Diag(ClsIvar->getLocation(), diag::note_previous_definition);
2205  }
2206  --numIvars;
2207  }
2208 
2209  if (numIvars > 0)
2210  Diag(ivars[j]->getLocation(), diag::err_inconsistent_ivar_count);
2211  else if (IVI != IVE)
2212  Diag(IVI->getLocation(), diag::err_inconsistent_ivar_count);
2213 }
2214 
2215 static void WarnUndefinedMethod(Sema &S, SourceLocation ImpLoc,
2216  ObjCMethodDecl *method,
2217  bool &IncompleteImpl,
2218  unsigned DiagID,
2219  NamedDecl *NeededFor = nullptr) {
2220  // No point warning no definition of method which is 'unavailable'.
2221  if (method->getAvailability() == AR_Unavailable)
2222  return;
2223 
2224  // FIXME: For now ignore 'IncompleteImpl'.
2225  // Previously we grouped all unimplemented methods under a single
2226  // warning, but some users strongly voiced that they would prefer
2227  // separate warnings. We will give that approach a try, as that
2228  // matches what we do with protocols.
2229  {
2230  const Sema::SemaDiagnosticBuilder &B = S.Diag(ImpLoc, DiagID);
2231  B << method;
2232  if (NeededFor)
2233  B << NeededFor;
2234  }
2235 
2236  // Issue a note to the original declaration.
2237  SourceLocation MethodLoc = method->getBeginLoc();
2238  if (MethodLoc.isValid())
2239  S.Diag(MethodLoc, diag::note_method_declared_at) << method;
2240 }
2241 
2242 /// Determines if type B can be substituted for type A. Returns true if we can
2243 /// guarantee that anything that the user will do to an object of type A can
2244 /// also be done to an object of type B. This is trivially true if the two
2245 /// types are the same, or if B is a subclass of A. It becomes more complex
2246 /// in cases where protocols are involved.
2247 ///
2248 /// Object types in Objective-C describe the minimum requirements for an
2249 /// object, rather than providing a complete description of a type. For
2250 /// example, if A is a subclass of B, then B* may refer to an instance of A.
2251 /// The principle of substitutability means that we may use an instance of A
2252 /// anywhere that we may use an instance of B - it will implement all of the
2253 /// ivars of B and all of the methods of B.
2254 ///
2255 /// This substitutability is important when type checking methods, because
2256 /// the implementation may have stricter type definitions than the interface.
2257 /// The interface specifies minimum requirements, but the implementation may
2258 /// have more accurate ones. For example, a method may privately accept
2259 /// instances of B, but only publish that it accepts instances of A. Any
2260 /// object passed to it will be type checked against B, and so will implicitly
2261 /// by a valid A*. Similarly, a method may return a subclass of the class that
2262 /// it is declared as returning.
2263 ///
2264 /// This is most important when considering subclassing. A method in a
2265 /// subclass must accept any object as an argument that its superclass's
2266 /// implementation accepts. It may, however, accept a more general type
2267 /// without breaking substitutability (i.e. you can still use the subclass
2268 /// anywhere that you can use the superclass, but not vice versa). The
2269 /// converse requirement applies to return types: the return type for a
2270 /// subclass method must be a valid object of the kind that the superclass
2271 /// advertises, but it may be specified more accurately. This avoids the need
2272 /// for explicit down-casting by callers.
2273 ///
2274 /// Note: This is a stricter requirement than for assignment.
2276  const ObjCObjectPointerType *A,
2277  const ObjCObjectPointerType *B,
2278  bool rejectId) {
2279  // Reject a protocol-unqualified id.
2280  if (rejectId && B->isObjCIdType()) return false;
2281 
2282  // If B is a qualified id, then A must also be a qualified id and it must
2283  // implement all of the protocols in B. It may not be a qualified class.
2284  // For example, MyClass<A> can be assigned to id<A>, but MyClass<A> is a
2285  // stricter definition so it is not substitutable for id<A>.
2286  if (B->isObjCQualifiedIdType()) {
2287  return A->isObjCQualifiedIdType() &&
2288  Context.ObjCQualifiedIdTypesAreCompatible(A, B, false);
2289  }
2290 
2291  /*
2292  // id is a special type that bypasses type checking completely. We want a
2293  // warning when it is used in one place but not another.
2294  if (C.isObjCIdType(A) || C.isObjCIdType(B)) return false;
2295 
2296 
2297  // If B is a qualified id, then A must also be a qualified id (which it isn't
2298  // if we've got this far)
2299  if (B->isObjCQualifiedIdType()) return false;
2300  */
2301 
2302  // Now we know that A and B are (potentially-qualified) class types. The
2303  // normal rules for assignment apply.
2304  return Context.canAssignObjCInterfaces(A, B);
2305 }
2306 
2308  return (TSI ? TSI->getTypeLoc().getSourceRange() : SourceRange());
2309 }
2310 
2311 /// Determine whether two set of Objective-C declaration qualifiers conflict.
2314  return (x & ~Decl::OBJC_TQ_CSNullability) !=
2315  (y & ~Decl::OBJC_TQ_CSNullability);
2316 }
2317 
2319  ObjCMethodDecl *MethodImpl,
2320  ObjCMethodDecl *MethodDecl,
2321  bool IsProtocolMethodDecl,
2322  bool IsOverridingMode,
2323  bool Warn) {
2324  if (IsProtocolMethodDecl &&
2326  MethodImpl->getObjCDeclQualifier())) {
2327  if (Warn) {
2328  S.Diag(MethodImpl->getLocation(),
2329  (IsOverridingMode
2330  ? diag::warn_conflicting_overriding_ret_type_modifiers
2331  : diag::warn_conflicting_ret_type_modifiers))
2332  << MethodImpl->getDeclName()
2333  << MethodImpl->getReturnTypeSourceRange();
2334  S.Diag(MethodDecl->getLocation(), diag::note_previous_declaration)
2335  << MethodDecl->getReturnTypeSourceRange();
2336  }
2337  else
2338  return false;
2339  }
2340  if (Warn && IsOverridingMode &&
2341  !isa<ObjCImplementationDecl>(MethodImpl->getDeclContext()) &&
2343  MethodDecl->getReturnType(),
2344  false)) {
2345  auto nullabilityMethodImpl =
2346  *MethodImpl->getReturnType()->getNullability(S.Context);
2347  auto nullabilityMethodDecl =
2348  *MethodDecl->getReturnType()->getNullability(S.Context);
2349  S.Diag(MethodImpl->getLocation(),
2350  diag::warn_conflicting_nullability_attr_overriding_ret_types)
2352  nullabilityMethodImpl,
2354  != 0))
2356  nullabilityMethodDecl,
2358  != 0));
2359  S.Diag(MethodDecl->getLocation(), diag::note_previous_declaration);
2360  }
2361 
2362  if (S.Context.hasSameUnqualifiedType(MethodImpl->getReturnType(),
2363  MethodDecl->getReturnType()))
2364  return true;
2365  if (!Warn)
2366  return false;
2367 
2368  unsigned DiagID =
2369  IsOverridingMode ? diag::warn_conflicting_overriding_ret_types
2370  : diag::warn_conflicting_ret_types;
2371 
2372  // Mismatches between ObjC pointers go into a different warning
2373  // category, and sometimes they're even completely explicitly allowed.
2374  if (const ObjCObjectPointerType *ImplPtrTy =
2375  MethodImpl->getReturnType()->getAs<ObjCObjectPointerType>()) {
2376  if (const ObjCObjectPointerType *IfacePtrTy =
2377  MethodDecl->getReturnType()->getAs<ObjCObjectPointerType>()) {
2378  // Allow non-matching return types as long as they don't violate
2379  // the principle of substitutability. Specifically, we permit
2380  // return types that are subclasses of the declared return type,
2381  // or that are more-qualified versions of the declared type.
2382  if (isObjCTypeSubstitutable(S.Context, IfacePtrTy, ImplPtrTy, false))
2383  return false;
2384 
2385  DiagID =
2386  IsOverridingMode ? diag::warn_non_covariant_overriding_ret_types
2387  : diag::warn_non_covariant_ret_types;
2388  }
2389  }
2390 
2391  S.Diag(MethodImpl->getLocation(), DiagID)
2392  << MethodImpl->getDeclName() << MethodDecl->getReturnType()
2393  << MethodImpl->getReturnType()
2394  << MethodImpl->getReturnTypeSourceRange();
2395  S.Diag(MethodDecl->getLocation(), IsOverridingMode
2396  ? diag::note_previous_declaration
2397  : diag::note_previous_definition)
2398  << MethodDecl->getReturnTypeSourceRange();
2399  return false;
2400 }
2401 
2403  ObjCMethodDecl *MethodImpl,
2404  ObjCMethodDecl *MethodDecl,
2405  ParmVarDecl *ImplVar,
2406  ParmVarDecl *IfaceVar,
2407  bool IsProtocolMethodDecl,
2408  bool IsOverridingMode,
2409  bool Warn) {
2410  if (IsProtocolMethodDecl &&
2412  IfaceVar->getObjCDeclQualifier())) {
2413  if (Warn) {
2414  if (IsOverridingMode)
2415  S.Diag(ImplVar->getLocation(),
2416  diag::warn_conflicting_overriding_param_modifiers)
2417  << getTypeRange(ImplVar->getTypeSourceInfo())
2418  << MethodImpl->getDeclName();
2419  else S.Diag(ImplVar->getLocation(),
2420  diag::warn_conflicting_param_modifiers)
2421  << getTypeRange(ImplVar->getTypeSourceInfo())
2422  << MethodImpl->getDeclName();
2423  S.Diag(IfaceVar->getLocation(), diag::note_previous_declaration)
2424  << getTypeRange(IfaceVar->getTypeSourceInfo());
2425  }
2426  else
2427  return false;
2428  }
2429 
2430  QualType ImplTy = ImplVar->getType();
2431  QualType IfaceTy = IfaceVar->getType();
2432  if (Warn && IsOverridingMode &&
2433  !isa<ObjCImplementationDecl>(MethodImpl->getDeclContext()) &&
2434  !S.Context.hasSameNullabilityTypeQualifier(ImplTy, IfaceTy, true)) {
2435  S.Diag(ImplVar->getLocation(),
2436  diag::warn_conflicting_nullability_attr_overriding_param_types)
2438  *ImplTy->getNullability(S.Context),
2440  != 0))
2442  *IfaceTy->getNullability(S.Context),
2444  != 0));
2445  S.Diag(IfaceVar->getLocation(), diag::note_previous_declaration);
2446  }
2447  if (S.Context.hasSameUnqualifiedType(ImplTy, IfaceTy))
2448  return true;
2449 
2450  if (!Warn)
2451  return false;
2452  unsigned DiagID =
2453  IsOverridingMode ? diag::warn_conflicting_overriding_param_types
2454  : diag::warn_conflicting_param_types;
2455 
2456  // Mismatches between ObjC pointers go into a different warning
2457  // category, and sometimes they're even completely explicitly allowed..
2458  if (const ObjCObjectPointerType *ImplPtrTy =
2459  ImplTy->getAs<ObjCObjectPointerType>()) {
2460  if (const ObjCObjectPointerType *IfacePtrTy =
2461  IfaceTy->getAs<ObjCObjectPointerType>()) {
2462  // Allow non-matching argument types as long as they don't
2463  // violate the principle of substitutability. Specifically, the
2464  // implementation must accept any objects that the superclass
2465  // accepts, however it may also accept others.
2466  if (isObjCTypeSubstitutable(S.Context, ImplPtrTy, IfacePtrTy, true))
2467  return false;
2468 
2469  DiagID =
2470  IsOverridingMode ? diag::warn_non_contravariant_overriding_param_types
2471  : diag::warn_non_contravariant_param_types;
2472  }
2473  }
2474 
2475  S.Diag(ImplVar->getLocation(), DiagID)
2476  << getTypeRange(ImplVar->getTypeSourceInfo())
2477  << MethodImpl->getDeclName() << IfaceTy << ImplTy;
2478  S.Diag(IfaceVar->getLocation(),
2479  (IsOverridingMode ? diag::note_previous_declaration
2480  : diag::note_previous_definition))
2481  << getTypeRange(IfaceVar->getTypeSourceInfo());
2482  return false;
2483 }
2484 
2485 /// In ARC, check whether the conventional meanings of the two methods
2486 /// match. If they don't, it's a hard error.
2488  ObjCMethodDecl *decl) {
2489  ObjCMethodFamily implFamily = impl->getMethodFamily();
2490  ObjCMethodFamily declFamily = decl->getMethodFamily();
2491  if (implFamily == declFamily) return false;
2492 
2493  // Since conventions are sorted by selector, the only possibility is
2494  // that the types differ enough to cause one selector or the other
2495  // to fall out of the family.
2496  assert(implFamily == OMF_None || declFamily == OMF_None);
2497 
2498  // No further diagnostics required on invalid declarations.
2499  if (impl->isInvalidDecl() || decl->isInvalidDecl()) return true;
2500 
2501  const ObjCMethodDecl *unmatched = impl;
2502  ObjCMethodFamily family = declFamily;
2503  unsigned errorID = diag::err_arc_lost_method_convention;
2504  unsigned noteID = diag::note_arc_lost_method_convention;
2505  if (declFamily == OMF_None) {
2506  unmatched = decl;
2507  family = implFamily;
2508  errorID = diag::err_arc_gained_method_convention;
2509  noteID = diag::note_arc_gained_method_convention;
2510  }
2511 
2512  // Indexes into a %select clause in the diagnostic.
2513  enum FamilySelector {
2514  F_alloc, F_copy, F_mutableCopy = F_copy, F_init, F_new
2515  };
2516  FamilySelector familySelector = FamilySelector();
2517 
2518  switch (family) {
2519  case OMF_None: llvm_unreachable("logic error, no method convention");
2520  case OMF_retain:
2521  case OMF_release:
2522  case OMF_autorelease:
2523  case OMF_dealloc:
2524  case OMF_finalize:
2525  case OMF_retainCount:
2526  case OMF_self:
2527  case OMF_initialize:
2528  case OMF_performSelector:
2529  // Mismatches for these methods don't change ownership
2530  // conventions, so we don't care.
2531  return false;
2532 
2533  case OMF_init: familySelector = F_init; break;
2534  case OMF_alloc: familySelector = F_alloc; break;
2535  case OMF_copy: familySelector = F_copy; break;
2536  case OMF_mutableCopy: familySelector = F_mutableCopy; break;
2537  case OMF_new: familySelector = F_new; break;
2538  }
2539 
2540  enum ReasonSelector { R_NonObjectReturn, R_UnrelatedReturn };
2541  ReasonSelector reasonSelector;
2542 
2543  // The only reason these methods don't fall within their families is
2544  // due to unusual result types.
2545  if (unmatched->getReturnType()->isObjCObjectPointerType()) {
2546  reasonSelector = R_UnrelatedReturn;
2547  } else {
2548  reasonSelector = R_NonObjectReturn;
2549  }
2550 
2551  S.Diag(impl->getLocation(), errorID) << int(familySelector) << int(reasonSelector);
2552  S.Diag(decl->getLocation(), noteID) << int(familySelector) << int(reasonSelector);
2553 
2554  return true;
2555 }
2556 
2558  ObjCMethodDecl *MethodDecl,
2559  bool IsProtocolMethodDecl) {
2560  if (getLangOpts().ObjCAutoRefCount &&
2561  checkMethodFamilyMismatch(*this, ImpMethodDecl, MethodDecl))
2562  return;
2563 
2564  CheckMethodOverrideReturn(*this, ImpMethodDecl, MethodDecl,
2565  IsProtocolMethodDecl, false,
2566  true);
2567 
2568  for (ObjCMethodDecl::param_iterator IM = ImpMethodDecl->param_begin(),
2569  IF = MethodDecl->param_begin(), EM = ImpMethodDecl->param_end(),
2570  EF = MethodDecl->param_end();
2571  IM != EM && IF != EF; ++IM, ++IF) {
2572  CheckMethodOverrideParam(*this, ImpMethodDecl, MethodDecl, *IM, *IF,
2573  IsProtocolMethodDecl, false, true);
2574  }
2575 
2576  if (ImpMethodDecl->isVariadic() != MethodDecl->isVariadic()) {
2577  Diag(ImpMethodDecl->getLocation(),
2578  diag::warn_conflicting_variadic);
2579  Diag(MethodDecl->getLocation(), diag::note_previous_declaration);
2580  }
2581 }
2582 
2584  ObjCMethodDecl *Overridden,
2585  bool IsProtocolMethodDecl) {
2586 
2587  CheckMethodOverrideReturn(*this, Method, Overridden,
2588  IsProtocolMethodDecl, true,
2589  true);
2590 
2591  for (ObjCMethodDecl::param_iterator IM = Method->param_begin(),
2592  IF = Overridden->param_begin(), EM = Method->param_end(),
2593  EF = Overridden->param_end();
2594  IM != EM && IF != EF; ++IM, ++IF) {
2595  CheckMethodOverrideParam(*this, Method, Overridden, *IM, *IF,
2596  IsProtocolMethodDecl, true, true);
2597  }
2598 
2599  if (Method->isVariadic() != Overridden->isVariadic()) {
2600  Diag(Method->getLocation(),
2601  diag::warn_conflicting_overriding_variadic);
2602  Diag(Overridden->getLocation(), diag::note_previous_declaration);
2603  }
2604 }
2605 
2606 /// WarnExactTypedMethods - This routine issues a warning if method
2607 /// implementation declaration matches exactly that of its declaration.
2609  ObjCMethodDecl *MethodDecl,
2610  bool IsProtocolMethodDecl) {
2611  // don't issue warning when protocol method is optional because primary
2612  // class is not required to implement it and it is safe for protocol
2613  // to implement it.
2615  return;
2616  // don't issue warning when primary class's method is
2617  // depecated/unavailable.
2618  if (MethodDecl->hasAttr<UnavailableAttr>() ||
2619  MethodDecl->hasAttr<DeprecatedAttr>())
2620  return;
2621 
2622  bool match = CheckMethodOverrideReturn(*this, ImpMethodDecl, MethodDecl,
2623  IsProtocolMethodDecl, false, false);
2624  if (match)
2625  for (ObjCMethodDecl::param_iterator IM = ImpMethodDecl->param_begin(),
2626  IF = MethodDecl->param_begin(), EM = ImpMethodDecl->param_end(),
2627  EF = MethodDecl->param_end();
2628  IM != EM && IF != EF; ++IM, ++IF) {
2629  match = CheckMethodOverrideParam(*this, ImpMethodDecl, MethodDecl,
2630  *IM, *IF,
2631  IsProtocolMethodDecl, false, false);
2632  if (!match)
2633  break;
2634  }
2635  if (match)
2636  match = (ImpMethodDecl->isVariadic() == MethodDecl->isVariadic());
2637  if (match)
2638  match = !(MethodDecl->isClassMethod() &&
2639  MethodDecl->getSelector() == GetNullarySelector("load", Context));
2640 
2641  if (match) {
2642  Diag(ImpMethodDecl->getLocation(),
2643  diag::warn_category_method_impl_match);
2644  Diag(MethodDecl->getLocation(), diag::note_method_declared_at)
2645  << MethodDecl->getDeclName();
2646  }
2647 }
2648 
2649 /// FIXME: Type hierarchies in Objective-C can be deep. We could most likely
2650 /// improve the efficiency of selector lookups and type checking by associating
2651 /// with each protocol / interface / category the flattened instance tables. If
2652 /// we used an immutable set to keep the table then it wouldn't add significant
2653 /// memory cost and it would be handy for lookups.
2654 
2656 typedef std::unique_ptr<ProtocolNameSet> LazyProtocolNameSet;
2657 
2659  ProtocolNameSet &PNS) {
2660  if (PDecl->hasAttr<ObjCExplicitProtocolImplAttr>())
2661  PNS.insert(PDecl->getIdentifier());
2662  for (const auto *PI : PDecl->protocols())
2664 }
2665 
2666 /// Recursively populates a set with all conformed protocols in a class
2667 /// hierarchy that have the 'objc_protocol_requires_explicit_implementation'
2668 /// attribute.
2670  ProtocolNameSet &PNS) {
2671  if (!Super)
2672  return;
2673 
2674  for (const auto *I : Super->all_referenced_protocols())
2676 
2678 }
2679 
2680 /// CheckProtocolMethodDefs - This routine checks unimplemented methods
2681 /// Declared in protocol, and those referenced by it.
2683  SourceLocation ImpLoc,
2684  ObjCProtocolDecl *PDecl,
2685  bool& IncompleteImpl,
2686  const Sema::SelectorSet &InsMap,
2687  const Sema::SelectorSet &ClsMap,
2688  ObjCContainerDecl *CDecl,
2689  LazyProtocolNameSet &ProtocolsExplictImpl) {
2690  ObjCCategoryDecl *C = dyn_cast<ObjCCategoryDecl>(CDecl);
2691  ObjCInterfaceDecl *IDecl = C ? C->getClassInterface()
2692  : dyn_cast<ObjCInterfaceDecl>(CDecl);
2693  assert (IDecl && "CheckProtocolMethodDefs - IDecl is null");
2694 
2695  ObjCInterfaceDecl *Super = IDecl->getSuperClass();
2696  ObjCInterfaceDecl *NSIDecl = nullptr;
2697 
2698  // If this protocol is marked 'objc_protocol_requires_explicit_implementation'
2699  // then we should check if any class in the super class hierarchy also
2700  // conforms to this protocol, either directly or via protocol inheritance.
2701  // If so, we can skip checking this protocol completely because we
2702  // know that a parent class already satisfies this protocol.
2703  //
2704  // Note: we could generalize this logic for all protocols, and merely
2705  // add the limit on looking at the super class chain for just
2706  // specially marked protocols. This may be a good optimization. This
2707  // change is restricted to 'objc_protocol_requires_explicit_implementation'
2708  // protocols for now for controlled evaluation.
2709  if (PDecl->hasAttr<ObjCExplicitProtocolImplAttr>()) {
2710  if (!ProtocolsExplictImpl) {
2711  ProtocolsExplictImpl.reset(new ProtocolNameSet);
2712  findProtocolsWithExplicitImpls(Super, *ProtocolsExplictImpl);
2713  }
2714  if (ProtocolsExplictImpl->find(PDecl->getIdentifier()) !=
2715  ProtocolsExplictImpl->end())
2716  return;
2717 
2718  // If no super class conforms to the protocol, we should not search
2719  // for methods in the super class to implicitly satisfy the protocol.
2720  Super = nullptr;
2721  }
2722 
2723  if (S.getLangOpts().ObjCRuntime.isNeXTFamily()) {
2724  // check to see if class implements forwardInvocation method and objects
2725  // of this class are derived from 'NSProxy' so that to forward requests
2726  // from one object to another.
2727  // Under such conditions, which means that every method possible is
2728  // implemented in the class, we should not issue "Method definition not
2729  // found" warnings.
2730  // FIXME: Use a general GetUnarySelector method for this.
2731  IdentifierInfo* II = &S.Context.Idents.get("forwardInvocation");
2732  Selector fISelector = S.Context.Selectors.getSelector(1, &II);
2733  if (InsMap.count(fISelector))
2734  // Is IDecl derived from 'NSProxy'? If so, no instance methods
2735  // need be implemented in the implementation.
2736  NSIDecl = IDecl->lookupInheritedClass(&S.Context.Idents.get("NSProxy"));
2737  }
2738 
2739  // If this is a forward protocol declaration, get its definition.
2740  if (!PDecl->isThisDeclarationADefinition() &&
2741  PDecl->getDefinition())
2742  PDecl = PDecl->getDefinition();
2743 
2744  // If a method lookup fails locally we still need to look and see if
2745  // the method was implemented by a base class or an inherited
2746  // protocol. This lookup is slow, but occurs rarely in correct code
2747  // and otherwise would terminate in a warning.
2748 
2749  // check unimplemented instance methods.
2750  if (!NSIDecl)
2751  for (auto *method : PDecl->instance_methods()) {
2752  if (method->getImplementationControl() != ObjCMethodDecl::Optional &&
2753  !method->isPropertyAccessor() &&
2754  !InsMap.count(method->getSelector()) &&
2755  (!Super || !Super->lookupMethod(method->getSelector(),
2756  true /* instance */,
2757  false /* shallowCategory */,
2758  true /* followsSuper */,
2759  nullptr /* category */))) {
2760  // If a method is not implemented in the category implementation but
2761  // has been declared in its primary class, superclass,
2762  // or in one of their protocols, no need to issue the warning.
2763  // This is because method will be implemented in the primary class
2764  // or one of its super class implementation.
2765 
2766  // Ugly, but necessary. Method declared in protocol might have
2767  // have been synthesized due to a property declared in the class which
2768  // uses the protocol.
2769  if (ObjCMethodDecl *MethodInClass =
2770  IDecl->lookupMethod(method->getSelector(),
2771  true /* instance */,
2772  true /* shallowCategoryLookup */,
2773  false /* followSuper */))
2774  if (C || MethodInClass->isPropertyAccessor())
2775  continue;
2776  unsigned DIAG = diag::warn_unimplemented_protocol_method;
2777  if (!S.Diags.isIgnored(DIAG, ImpLoc)) {
2778  WarnUndefinedMethod(S, ImpLoc, method, IncompleteImpl, DIAG,
2779  PDecl);
2780  }
2781  }
2782  }
2783  // check unimplemented class methods
2784  for (auto *method : PDecl->class_methods()) {
2785  if (method->getImplementationControl() != ObjCMethodDecl::Optional &&
2786  !ClsMap.count(method->getSelector()) &&
2787  (!Super || !Super->lookupMethod(method->getSelector(),
2788  false /* class method */,
2789  false /* shallowCategoryLookup */,
2790  true /* followSuper */,
2791  nullptr /* category */))) {
2792  // See above comment for instance method lookups.
2793  if (C && IDecl->lookupMethod(method->getSelector(),
2794  false /* class */,
2795  true /* shallowCategoryLookup */,
2796  false /* followSuper */))
2797  continue;
2798 
2799  unsigned DIAG = diag::warn_unimplemented_protocol_method;
2800  if (!S.Diags.isIgnored(DIAG, ImpLoc)) {
2801  WarnUndefinedMethod(S, ImpLoc, method, IncompleteImpl, DIAG, PDecl);
2802  }
2803  }
2804  }
2805  // Check on this protocols's referenced protocols, recursively.
2806  for (auto *PI : PDecl->protocols())
2807  CheckProtocolMethodDefs(S, ImpLoc, PI, IncompleteImpl, InsMap, ClsMap,
2808  CDecl, ProtocolsExplictImpl);
2809 }
2810 
2811 /// MatchAllMethodDeclarations - Check methods declared in interface
2812 /// or protocol against those declared in their implementations.
2813 ///
2815  const SelectorSet &ClsMap,
2816  SelectorSet &InsMapSeen,
2817  SelectorSet &ClsMapSeen,
2818  ObjCImplDecl* IMPDecl,
2819  ObjCContainerDecl* CDecl,
2820  bool &IncompleteImpl,
2821  bool ImmediateClass,
2822  bool WarnCategoryMethodImpl) {
2823  // Check and see if instance methods in class interface have been
2824  // implemented in the implementation class. If so, their types match.
2825  for (auto *I : CDecl->instance_methods()) {
2826  if (!InsMapSeen.insert(I->getSelector()).second)
2827  continue;
2828  if (!I->isPropertyAccessor() &&
2829  !InsMap.count(I->getSelector())) {
2830  if (ImmediateClass)
2831  WarnUndefinedMethod(*this, IMPDecl->getLocation(), I, IncompleteImpl,
2832  diag::warn_undef_method_impl);
2833  continue;
2834  } else {
2835  ObjCMethodDecl *ImpMethodDecl =
2836  IMPDecl->getInstanceMethod(I->getSelector());
2837  assert(CDecl->getInstanceMethod(I->getSelector(), true/*AllowHidden*/) &&
2838  "Expected to find the method through lookup as well");
2839  // ImpMethodDecl may be null as in a @dynamic property.
2840  if (ImpMethodDecl) {
2841  // Skip property accessor function stubs.
2842  if (ImpMethodDecl->isSynthesizedAccessorStub())
2843  continue;
2844  if (!WarnCategoryMethodImpl)
2845  WarnConflictingTypedMethods(ImpMethodDecl, I,
2846  isa<ObjCProtocolDecl>(CDecl));
2847  else if (!I->isPropertyAccessor())
2848  WarnExactTypedMethods(ImpMethodDecl, I, isa<ObjCProtocolDecl>(CDecl));
2849  }
2850  }
2851  }
2852 
2853  // Check and see if class methods in class interface have been
2854  // implemented in the implementation class. If so, their types match.
2855  for (auto *I : CDecl->class_methods()) {
2856  if (!ClsMapSeen.insert(I->getSelector()).second)
2857  continue;
2858  if (!I->isPropertyAccessor() &&
2859  !ClsMap.count(I->getSelector())) {
2860  if (ImmediateClass)
2861  WarnUndefinedMethod(*this, IMPDecl->getLocation(), I, IncompleteImpl,
2862  diag::warn_undef_method_impl);
2863  } else {
2864  ObjCMethodDecl *ImpMethodDecl =
2865  IMPDecl->getClassMethod(I->getSelector());
2866  assert(CDecl->getClassMethod(I->getSelector(), true/*AllowHidden*/) &&
2867  "Expected to find the method through lookup as well");
2868  // ImpMethodDecl may be null as in a @dynamic property.
2869  if (ImpMethodDecl) {
2870  // Skip property accessor function stubs.
2871  if (ImpMethodDecl->isSynthesizedAccessorStub())
2872  continue;
2873  if (!WarnCategoryMethodImpl)
2874  WarnConflictingTypedMethods(ImpMethodDecl, I,
2875  isa<ObjCProtocolDecl>(CDecl));
2876  else if (!I->isPropertyAccessor())
2877  WarnExactTypedMethods(ImpMethodDecl, I, isa<ObjCProtocolDecl>(CDecl));
2878  }
2879  }
2880  }
2881 
2882  if (ObjCProtocolDecl *PD = dyn_cast<ObjCProtocolDecl> (CDecl)) {
2883  // Also, check for methods declared in protocols inherited by
2884  // this protocol.
2885  for (auto *PI : PD->protocols())
2886  MatchAllMethodDeclarations(InsMap, ClsMap, InsMapSeen, ClsMapSeen,
2887  IMPDecl, PI, IncompleteImpl, false,
2888  WarnCategoryMethodImpl);
2889  }
2890 
2891  if (ObjCInterfaceDecl *I = dyn_cast<ObjCInterfaceDecl> (CDecl)) {
2892  // when checking that methods in implementation match their declaration,
2893  // i.e. when WarnCategoryMethodImpl is false, check declarations in class
2894  // extension; as well as those in categories.
2895  if (!WarnCategoryMethodImpl) {
2896  for (auto *Cat : I->visible_categories())
2897  MatchAllMethodDeclarations(InsMap, ClsMap, InsMapSeen, ClsMapSeen,
2898  IMPDecl, Cat, IncompleteImpl,
2899  ImmediateClass && Cat->IsClassExtension(),
2900  WarnCategoryMethodImpl);
2901  } else {
2902  // Also methods in class extensions need be looked at next.
2903  for (auto *Ext : I->visible_extensions())
2904  MatchAllMethodDeclarations(InsMap, ClsMap, InsMapSeen, ClsMapSeen,
2905  IMPDecl, Ext, IncompleteImpl, false,
2906  WarnCategoryMethodImpl);
2907  }
2908 
2909  // Check for any implementation of a methods declared in protocol.
2910  for (auto *PI : I->all_referenced_protocols())
2911  MatchAllMethodDeclarations(InsMap, ClsMap, InsMapSeen, ClsMapSeen,
2912  IMPDecl, PI, IncompleteImpl, false,
2913  WarnCategoryMethodImpl);
2914 
2915  // FIXME. For now, we are not checking for exact match of methods
2916  // in category implementation and its primary class's super class.
2917  if (!WarnCategoryMethodImpl && I->getSuperClass())
2918  MatchAllMethodDeclarations(InsMap, ClsMap, InsMapSeen, ClsMapSeen,
2919  IMPDecl,
2920  I->getSuperClass(), IncompleteImpl, false);
2921  }
2922 }
2923 
2924 /// CheckCategoryVsClassMethodMatches - Checks that methods implemented in
2925 /// category matches with those implemented in its primary class and
2926 /// warns each time an exact match is found.
2928  ObjCCategoryImplDecl *CatIMPDecl) {
2929  // Get category's primary class.
2930  ObjCCategoryDecl *CatDecl = CatIMPDecl->getCategoryDecl();
2931  if (!CatDecl)
2932  return;
2933  ObjCInterfaceDecl *IDecl = CatDecl->getClassInterface();
2934  if (!IDecl)
2935  return;
2936  ObjCInterfaceDecl *SuperIDecl = IDecl->getSuperClass();
2937  SelectorSet InsMap, ClsMap;
2938 
2939  for (const auto *I : CatIMPDecl->instance_methods()) {
2940  Selector Sel = I->getSelector();
2941  // When checking for methods implemented in the category, skip over
2942  // those declared in category class's super class. This is because
2943  // the super class must implement the method.
2944  if (SuperIDecl && SuperIDecl->lookupMethod(Sel, true))
2945  continue;
2946  InsMap.insert(Sel);
2947  }
2948 
2949  for (const auto *I : CatIMPDecl->class_methods()) {
2950  Selector Sel = I->getSelector();
2951  if (SuperIDecl && SuperIDecl->lookupMethod(Sel, false))
2952  continue;
2953  ClsMap.insert(Sel);
2954  }
2955  if (InsMap.empty() && ClsMap.empty())
2956  return;
2957 
2958  SelectorSet InsMapSeen, ClsMapSeen;
2959  bool IncompleteImpl = false;
2960  MatchAllMethodDeclarations(InsMap, ClsMap, InsMapSeen, ClsMapSeen,
2961  CatIMPDecl, IDecl,
2962  IncompleteImpl, false,
2963  true /*WarnCategoryMethodImpl*/);
2964 }
2965 
2967  ObjCContainerDecl* CDecl,
2968  bool IncompleteImpl) {
2969  SelectorSet InsMap;
2970  // Check and see if instance methods in class interface have been
2971  // implemented in the implementation class.
2972  for (const auto *I : IMPDecl->instance_methods())
2973  InsMap.insert(I->getSelector());
2974 
2975  // Add the selectors for getters/setters of @dynamic properties.
2976  for (const auto *PImpl : IMPDecl->property_impls()) {
2977  // We only care about @dynamic implementations.
2978  if (PImpl->getPropertyImplementation() != ObjCPropertyImplDecl::Dynamic)
2979  continue;
2980 
2981  const auto *P = PImpl->getPropertyDecl();
2982  if (!P) continue;
2983 
2984  InsMap.insert(P->getGetterName());
2985  if (!P->getSetterName().isNull())
2986  InsMap.insert(P->getSetterName());
2987  }
2988 
2989  // Check and see if properties declared in the interface have either 1)
2990  // an implementation or 2) there is a @synthesize/@dynamic implementation
2991  // of the property in the @implementation.
2992  if (const ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(CDecl)) {
2993  bool SynthesizeProperties = LangOpts.ObjCDefaultSynthProperties &&
2995  !IDecl->isObjCRequiresPropertyDefs();
2996  DiagnoseUnimplementedProperties(S, IMPDecl, CDecl, SynthesizeProperties);
2997  }
2998 
2999  // Diagnose null-resettable synthesized setters.
3001 
3002  SelectorSet ClsMap;
3003  for (const auto *I : IMPDecl->class_methods())
3004  ClsMap.insert(I->getSelector());
3005 
3006  // Check for type conflict of methods declared in a class/protocol and
3007  // its implementation; if any.
3008  SelectorSet InsMapSeen, ClsMapSeen;
3009  MatchAllMethodDeclarations(InsMap, ClsMap, InsMapSeen, ClsMapSeen,
3010  IMPDecl, CDecl,
3011  IncompleteImpl, true);
3012 
3013  // check all methods implemented in category against those declared
3014  // in its primary class.
3015  if (ObjCCategoryImplDecl *CatDecl =
3016  dyn_cast<ObjCCategoryImplDecl>(IMPDecl))
3018 
3019  // Check the protocol list for unimplemented methods in the @implementation
3020  // class.
3021  // Check and see if class methods in class interface have been
3022  // implemented in the implementation class.
3023 
3024  LazyProtocolNameSet ExplicitImplProtocols;
3025 
3026  if (ObjCInterfaceDecl *I = dyn_cast<ObjCInterfaceDecl> (CDecl)) {
3027  for (auto *PI : I->all_referenced_protocols())
3028  CheckProtocolMethodDefs(*this, IMPDecl->getLocation(), PI, IncompleteImpl,
3029  InsMap, ClsMap, I, ExplicitImplProtocols);
3030  } else if (ObjCCategoryDecl *C = dyn_cast<ObjCCategoryDecl>(CDecl)) {
3031  // For extended class, unimplemented methods in its protocols will
3032  // be reported in the primary class.
3033  if (!C->IsClassExtension()) {
3034  for (auto *P : C->protocols())
3035  CheckProtocolMethodDefs(*this, IMPDecl->getLocation(), P,
3036  IncompleteImpl, InsMap, ClsMap, CDecl,
3037  ExplicitImplProtocols);
3038  DiagnoseUnimplementedProperties(S, IMPDecl, CDecl,
3039  /*SynthesizeProperties=*/false);
3040  }
3041  } else
3042  llvm_unreachable("invalid ObjCContainerDecl type.");
3043 }
3044 
3047  IdentifierInfo **IdentList,
3048  SourceLocation *IdentLocs,
3049  ArrayRef<ObjCTypeParamList *> TypeParamLists,
3050  unsigned NumElts) {
3051  SmallVector<Decl *, 8> DeclsInGroup;
3052  for (unsigned i = 0; i != NumElts; ++i) {
3053  // Check for another declaration kind with the same name.
3054  NamedDecl *PrevDecl
3055  = LookupSingleName(TUScope, IdentList[i], IdentLocs[i],
3057  if (PrevDecl && !isa<ObjCInterfaceDecl>(PrevDecl)) {
3058  // GCC apparently allows the following idiom:
3059  //
3060  // typedef NSObject < XCElementTogglerP > XCElementToggler;
3061  // @class XCElementToggler;
3062  //
3063  // Here we have chosen to ignore the forward class declaration
3064  // with a warning. Since this is the implied behavior.
3065  TypedefNameDecl *TDD = dyn_cast<TypedefNameDecl>(PrevDecl);
3066  if (!TDD || !TDD->getUnderlyingType()->isObjCObjectType()) {
3067  Diag(AtClassLoc, diag::err_redefinition_different_kind) << IdentList[i];
3068  Diag(PrevDecl->getLocation(), diag::note_previous_definition);
3069  } else {
3070  // a forward class declaration matching a typedef name of a class refers
3071  // to the underlying class. Just ignore the forward class with a warning
3072  // as this will force the intended behavior which is to lookup the
3073  // typedef name.
3074  if (isa<ObjCObjectType>(TDD->getUnderlyingType())) {
3075  Diag(AtClassLoc, diag::warn_forward_class_redefinition)
3076  << IdentList[i];
3077  Diag(PrevDecl->getLocation(), diag::note_previous_definition);
3078  continue;
3079  }
3080  }
3081  }
3082 
3083  // Create a declaration to describe this forward declaration.
3084  ObjCInterfaceDecl *PrevIDecl
3085  = dyn_cast_or_null<ObjCInterfaceDecl>(PrevDecl);
3086 
3087  IdentifierInfo *ClassName = IdentList[i];
3088  if (PrevIDecl && PrevIDecl->getIdentifier() != ClassName) {
3089  // A previous decl with a different name is because of
3090  // @compatibility_alias, for example:
3091  // \code
3092  // @class NewImage;
3093  // @compatibility_alias OldImage NewImage;
3094  // \endcode
3095  // A lookup for 'OldImage' will return the 'NewImage' decl.
3096  //
3097  // In such a case use the real declaration name, instead of the alias one,
3098  // otherwise we will break IdentifierResolver and redecls-chain invariants.
3099  // FIXME: If necessary, add a bit to indicate that this ObjCInterfaceDecl
3100  // has been aliased.
3101  ClassName = PrevIDecl->getIdentifier();
3102  }
3103 
3104  // If this forward declaration has type parameters, compare them with the
3105  // type parameters of the previous declaration.
3106  ObjCTypeParamList *TypeParams = TypeParamLists[i];
3107  if (PrevIDecl && TypeParams) {
3108  if (ObjCTypeParamList *PrevTypeParams = PrevIDecl->getTypeParamList()) {
3109  // Check for consistency with the previous declaration.
3111  *this, PrevTypeParams, TypeParams,
3112  TypeParamListContext::ForwardDeclaration)) {
3113  TypeParams = nullptr;
3114  }
3115  } else if (ObjCInterfaceDecl *Def = PrevIDecl->getDefinition()) {
3116  // The @interface does not have type parameters. Complain.
3117  Diag(IdentLocs[i], diag::err_objc_parameterized_forward_class)
3118  << ClassName
3119  << TypeParams->getSourceRange();
3120  Diag(Def->getLocation(), diag::note_defined_here)
3121  << ClassName;
3122 
3123  TypeParams = nullptr;
3124  }
3125  }
3126 
3127  ObjCInterfaceDecl *IDecl
3129  ClassName, TypeParams, PrevIDecl,
3130  IdentLocs[i]);
3131  IDecl->setAtEndRange(IdentLocs[i]);
3132 
3133  if (PrevIDecl)
3134  mergeDeclAttributes(IDecl, PrevIDecl);
3135 
3136  PushOnScopeChains(IDecl, TUScope);
3137  CheckObjCDeclScope(IDecl);
3138  DeclsInGroup.push_back(IDecl);
3139  }
3140 
3141  return BuildDeclaratorGroup(DeclsInGroup);
3142 }
3143 
3144 static bool tryMatchRecordTypes(ASTContext &Context,
3145  Sema::MethodMatchStrategy strategy,
3146  const Type *left, const Type *right);
3147 
3148 static bool matchTypes(ASTContext &Context, Sema::MethodMatchStrategy strategy,
3149  QualType leftQT, QualType rightQT) {
3150  const Type *left =
3151  Context.getCanonicalType(leftQT).getUnqualifiedType().getTypePtr();
3152  const Type *right =
3153  Context.getCanonicalType(rightQT).getUnqualifiedType().getTypePtr();
3154 
3155  if (left == right) return true;
3156 
3157  // If we're doing a strict match, the types have to match exactly.
3158  if (strategy == Sema::MMS_strict) return false;
3159 
3160  if (left->isIncompleteType() || right->isIncompleteType()) return false;
3161 
3162  // Otherwise, use this absurdly complicated algorithm to try to
3163  // validate the basic, low-level compatibility of the two types.
3164 
3165  // As a minimum, require the sizes and alignments to match.
3166  TypeInfo LeftTI = Context.getTypeInfo(left);
3167  TypeInfo RightTI = Context.getTypeInfo(right);
3168  if (LeftTI.Width != RightTI.Width)
3169  return false;
3170 
3171  if (LeftTI.Align != RightTI.Align)
3172  return false;
3173 
3174  // Consider all the kinds of non-dependent canonical types:
3175  // - functions and arrays aren't possible as return and parameter types
3176 
3177  // - vector types of equal size can be arbitrarily mixed
3178  if (isa<VectorType>(left)) return isa<VectorType>(right);
3179  if (isa<VectorType>(right)) return false;
3180 
3181  // - references should only match references of identical type
3182  // - structs, unions, and Objective-C objects must match more-or-less
3183  // exactly
3184  // - everything else should be a scalar
3185  if (!left->isScalarType() || !right->isScalarType())
3186  return tryMatchRecordTypes(Context, strategy, left, right);
3187 
3188  // Make scalars agree in kind, except count bools as chars, and group
3189  // all non-member pointers together.
3190  Type::ScalarTypeKind leftSK = left->getScalarTypeKind();
3191  Type::ScalarTypeKind rightSK = right->getScalarTypeKind();
3192  if (leftSK == Type::STK_Bool) leftSK = Type::STK_Integral;
3193  if (rightSK == Type::STK_Bool) rightSK = Type::STK_Integral;
3194  if (leftSK == Type::STK_CPointer || leftSK == Type::STK_BlockPointer)
3195  leftSK = Type::STK_ObjCObjectPointer;
3196  if (rightSK == Type::STK_CPointer || rightSK == Type::STK_BlockPointer)
3197  rightSK = Type::STK_ObjCObjectPointer;
3198 
3199  // Note that data member pointers and function member pointers don't
3200  // intermix because of the size differences.
3201 
3202  return (leftSK == rightSK);
3203 }
3204 
3205 static bool tryMatchRecordTypes(ASTContext &Context,
3206  Sema::MethodMatchStrategy strategy,
3207  const Type *lt, const Type *rt) {
3208  assert(lt && rt && lt != rt);
3209 
3210  if (!isa<RecordType>(lt) || !isa<RecordType>(rt)) return false;
3211  RecordDecl *left = cast<RecordType>(lt)->getDecl();
3212  RecordDecl *right = cast<RecordType>(rt)->getDecl();
3213 
3214  // Require union-hood to match.
3215  if (left->isUnion() != right->isUnion()) return false;
3216 
3217  // Require an exact match if either is non-POD.
3218  if ((isa<CXXRecordDecl>(left) && !cast<CXXRecordDecl>(left)->isPOD()) ||
3219  (isa<CXXRecordDecl>(right) && !cast<CXXRecordDecl>(right)->isPOD()))
3220  return false;
3221 
3222  // Require size and alignment to match.
3223  TypeInfo LeftTI = Context.getTypeInfo(lt);
3224  TypeInfo RightTI = Context.getTypeInfo(rt);
3225  if (LeftTI.Width != RightTI.Width)
3226  return false;
3227 
3228  if (LeftTI.Align != RightTI.Align)
3229  return false;
3230 
3231  // Require fields to match.
3232  RecordDecl::field_iterator li = left->field_begin(), le = left->field_end();
3233  RecordDecl::field_iterator ri = right->field_begin(), re = right->field_end();
3234  for (; li != le && ri != re; ++li, ++ri) {
3235  if (!matchTypes(Context, strategy, li->getType(), ri->getType()))
3236  return false;
3237  }
3238  return (li == le && ri == re);
3239 }
3240 
3241 /// MatchTwoMethodDeclarations - Checks that two methods have matching type and
3242 /// returns true, or false, accordingly.
3243 /// TODO: Handle protocol list; such as id<p1,p2> in type comparisons
3245  const ObjCMethodDecl *right,
3246  MethodMatchStrategy strategy) {
3247  if (!matchTypes(Context, strategy, left->getReturnType(),
3248  right->getReturnType()))
3249  return false;
3250 
3251  // If either is hidden, it is not considered to match.
3252  if (!left->isUnconditionallyVisible() || !right->isUnconditionallyVisible())
3253  return false;
3254 
3255  if (left->isDirectMethod() != right->isDirectMethod())
3256  return false;
3257 
3258  if (getLangOpts().ObjCAutoRefCount &&
3259  (left->hasAttr<NSReturnsRetainedAttr>()
3260  != right->hasAttr<NSReturnsRetainedAttr>() ||
3261  left->hasAttr<NSConsumesSelfAttr>()
3262  != right->hasAttr<NSConsumesSelfAttr>()))
3263  return false;
3264 
3266  li = left->param_begin(), le = left->param_end(), ri = right->param_begin(),
3267  re = right->param_end();
3268 
3269  for (; li != le && ri != re; ++li, ++ri) {
3270  assert(ri != right->param_end() && "Param mismatch");
3271  const ParmVarDecl *lparm = *li, *rparm = *ri;
3272 
3273  if (!matchTypes(Context, strategy, lparm->getType(), rparm->getType()))
3274  return false;
3275 
3276  if (getLangOpts().ObjCAutoRefCount &&
3277  lparm->hasAttr<NSConsumedAttr>() != rparm->hasAttr<NSConsumedAttr>())
3278  return false;
3279  }
3280  return true;
3281 }
3282 
3284  ObjCMethodDecl *MethodInList) {
3285  auto *MethodProtocol = dyn_cast<ObjCProtocolDecl>(Method->getDeclContext());
3286  auto *MethodInListProtocol =
3287  dyn_cast<ObjCProtocolDecl>(MethodInList->getDeclContext());
3288  // If this method belongs to a protocol but the method in list does not, or
3289  // vice versa, we say the context is not the same.
3290  if ((MethodProtocol && !MethodInListProtocol) ||
3291  (!MethodProtocol && MethodInListProtocol))
3292  return false;
3293 
3294  if (MethodProtocol && MethodInListProtocol)
3295  return true;
3296 
3297  ObjCInterfaceDecl *MethodInterface = Method->getClassInterface();
3298  ObjCInterfaceDecl *MethodInListInterface =
3299  MethodInList->getClassInterface();
3300  return MethodInterface == MethodInListInterface;
3301 }
3302 
3304  ObjCMethodDecl *Method) {
3305  // Record at the head of the list whether there were 0, 1, or >= 2 methods
3306  // inside categories.
3307  if (ObjCCategoryDecl *CD =
3308  dyn_cast<ObjCCategoryDecl>(Method->getDeclContext()))
3309  if (!CD->IsClassExtension() && List->getBits() < 2)
3310  List->setBits(List->getBits() + 1);
3311 
3312  // If the list is empty, make it a singleton list.
3313  if (List->getMethod() == nullptr) {
3314  List->setMethod(Method);
3315  List->setNext(nullptr);
3316  return;
3317  }
3318 
3319  // We've seen a method with this name, see if we have already seen this type
3320  // signature.
3321  ObjCMethodList *Previous = List;
3322  ObjCMethodList *ListWithSameDeclaration = nullptr;
3323  for (; List; Previous = List, List = List->getNext()) {
3324  // If we are building a module, keep all of the methods.
3326  continue;
3327 
3328  bool SameDeclaration = MatchTwoMethodDeclarations(Method,
3329  List->getMethod());
3330  // Looking for method with a type bound requires the correct context exists.
3331  // We need to insert a method into the list if the context is different.
3332  // If the method's declaration matches the list
3333  // a> the method belongs to a different context: we need to insert it, in
3334  // order to emit the availability message, we need to prioritize over
3335  // availability among the methods with the same declaration.
3336  // b> the method belongs to the same context: there is no need to insert a
3337  // new entry.
3338  // If the method's declaration does not match the list, we insert it to the
3339  // end.
3340  if (!SameDeclaration ||
3341  !isMethodContextSameForKindofLookup(Method, List->getMethod())) {
3342  // Even if two method types do not match, we would like to say
3343  // there is more than one declaration so unavailability/deprecated
3344  // warning is not too noisy.
3345  if (!Method->isDefined())
3346  List->setHasMoreThanOneDecl(true);
3347 
3348  // For methods with the same declaration, the one that is deprecated
3349  // should be put in the front for better diagnostics.
3350  if (Method->isDeprecated() && SameDeclaration &&
3351  !ListWithSameDeclaration && !List->getMethod()->isDeprecated())
3352  ListWithSameDeclaration = List;
3353 
3354  if (Method->isUnavailable() && SameDeclaration &&
3355  !ListWithSameDeclaration &&
3356  List->getMethod()->getAvailability() < AR_Deprecated)
3357  ListWithSameDeclaration = List;
3358  continue;
3359  }
3360 
3361  ObjCMethodDecl *PrevObjCMethod = List->getMethod();
3362 
3363  // Propagate the 'defined' bit.
3364  if (Method->isDefined())
3365  PrevObjCMethod->setDefined(true);
3366  else {
3367  // Objective-C doesn't allow an @interface for a class after its
3368  // @implementation. So if Method is not defined and there already is
3369  // an entry for this type signature, Method has to be for a different
3370  // class than PrevObjCMethod.
3371  List->setHasMoreThanOneDecl(true);
3372  }
3373 
3374  // If a method is deprecated, push it in the global pool.
3375  // This is used for better diagnostics.
3376  if (Method->isDeprecated()) {
3377  if (!PrevObjCMethod->isDeprecated())
3378  List->setMethod(Method);
3379  }
3380  // If the new method is unavailable, push it into global pool
3381  // unless previous one is deprecated.
3382  if (Method->isUnavailable()) {
3383  if (PrevObjCMethod->getAvailability() < AR_Deprecated)
3384  List->setMethod(Method);
3385  }
3386 
3387  return;
3388  }
3389 
3390  // We have a new signature for an existing method - add it.
3391  // This is extremely rare. Only 1% of Cocoa selectors are "overloaded".
3392  ObjCMethodList *Mem = BumpAlloc.Allocate<ObjCMethodList>();
3393 
3394  // We insert it right before ListWithSameDeclaration.
3395  if (ListWithSameDeclaration) {
3396  auto *List = new (Mem) ObjCMethodList(*ListWithSameDeclaration);
3397  // FIXME: should we clear the other bits in ListWithSameDeclaration?
3398  ListWithSameDeclaration->setMethod(Method);
3399  ListWithSameDeclaration->setNext(List);
3400  return;
3401  }
3402 
3403  Previous->setNext(new (Mem) ObjCMethodList(Method));
3404 }
3405 
3406 /// Read the contents of the method pool for a given selector from
3407 /// external storage.
3409  assert(ExternalSource && "We need an external AST source");
3410  ExternalSource->ReadMethodPool(Sel);
3411 }
3412 
3414  if (!ExternalSource)
3415  return;
3416  ExternalSource->updateOutOfDateSelector(Sel);
3417 }
3418 
3419 void Sema::AddMethodToGlobalPool(ObjCMethodDecl *Method, bool impl,
3420  bool instance) {
3421  // Ignore methods of invalid containers.
3422  if (cast<Decl>(Method->getDeclContext())->isInvalidDecl())
3423  return;
3424 
3425  if (ExternalSource)
3426  ReadMethodPool(Method->getSelector());
3427 
3428  GlobalMethodPool::iterator Pos = MethodPool.find(Method->getSelector());
3429  if (Pos == MethodPool.end())
3430  Pos = MethodPool.insert(std::make_pair(Method->getSelector(),
3431  GlobalMethods())).first;
3432 
3433  Method->setDefined(impl);
3434 
3435  ObjCMethodList &Entry = instance ? Pos->second.first : Pos->second.second;
3436  addMethodToGlobalList(&Entry, Method);
3437 }
3438 
3439 /// Determines if this is an "acceptable" loose mismatch in the global
3440 /// method pool. This exists mostly as a hack to get around certain
3441 /// global mismatches which we can't afford to make warnings / errors.
3442 /// Really, what we want is a way to take a method out of the global
3443 /// method pool.
3445  ObjCMethodDecl *other) {
3446  if (!chosen->isInstanceMethod())
3447  return false;
3448 
3449  if (chosen->isDirectMethod() != other->isDirectMethod())
3450  return false;
3451 
3452  Selector sel = chosen->getSelector();
3453  if (!sel.isUnarySelector() || sel.getNameForSlot(0) != "length")
3454  return false;
3455 
3456  // Don't complain about mismatches for -length if the method we
3457  // chose has an integral result type.
3458  return (chosen->getReturnType()->isIntegerType());
3459 }
3460 
3461 /// Return true if the given method is wthin the type bound.
3463  const ObjCObjectType *TypeBound) {
3464  if (!TypeBound)
3465  return true;
3466 
3467  if (TypeBound->isObjCId())
3468  // FIXME: should we handle the case of bounding to id<A, B> differently?
3469  return true;
3470 
3471  auto *BoundInterface = TypeBound->getInterface();
3472  assert(BoundInterface && "unexpected object type!");
3473 
3474  // Check if the Method belongs to a protocol. We should allow any method
3475  // defined in any protocol, because any subclass could adopt the protocol.
3476  auto *MethodProtocol = dyn_cast<ObjCProtocolDecl>(Method->getDeclContext());
3477  if (MethodProtocol) {
3478  return true;
3479  }
3480 
3481  // If the Method belongs to a class, check if it belongs to the class
3482  // hierarchy of the class bound.
3483  if (ObjCInterfaceDecl *MethodInterface = Method->getClassInterface()) {
3484  // We allow methods declared within classes that are part of the hierarchy
3485  // of the class bound (superclass of, subclass of, or the same as the class
3486  // bound).
3487  return MethodInterface == BoundInterface ||
3488  MethodInterface->isSuperClassOf(BoundInterface) ||
3489  BoundInterface->isSuperClassOf(MethodInterface);
3490  }
3491  llvm_unreachable("unknown method context");
3492 }
3493 
3494 /// We first select the type of the method: Instance or Factory, then collect
3495 /// all methods with that type.
3498  bool InstanceFirst, bool CheckTheOther,
3499  const ObjCObjectType *TypeBound) {
3500  if (ExternalSource)
3501  ReadMethodPool(Sel);
3502 
3503  GlobalMethodPool::iterator Pos = MethodPool.find(Sel);
3504  if (Pos == MethodPool.end())
3505  return false;
3506 
3507  // Gather the non-hidden methods.
3508  ObjCMethodList &MethList = InstanceFirst ? Pos->second.first :
3509  Pos->second.second;
3510  for (ObjCMethodList *M = &MethList; M; M = M->getNext())
3511  if (M->getMethod() && M->getMethod()->isUnconditionallyVisible()) {
3512  if (FilterMethodsByTypeBound(M->getMethod(), TypeBound))
3513  Methods.push_back(M->getMethod());
3514  }
3515 
3516  // Return if we find any method with the desired kind.
3517  if (!Methods.empty())
3518  return Methods.size() > 1;
3519 
3520  if (!CheckTheOther)
3521  return false;
3522 
3523  // Gather the other kind.
3524  ObjCMethodList &MethList2 = InstanceFirst ? Pos->second.second :
3525  Pos->second.first;
3526  for (ObjCMethodList *M = &MethList2; M; M = M->getNext())
3527  if (M->getMethod() && M->getMethod()->isUnconditionallyVisible()) {
3528  if (FilterMethodsByTypeBound(M->getMethod(), TypeBound))
3529  Methods.push_back(M->getMethod());
3530  }
3531 
3532  return Methods.size() > 1;
3533 }
3534 
3536  Selector Sel, ObjCMethodDecl *BestMethod, SourceRange R,
3537  bool receiverIdOrClass, SmallVectorImpl<ObjCMethodDecl *> &Methods) {
3538  // Diagnose finding more than one method in global pool.
3539  SmallVector<ObjCMethodDecl *, 4> FilteredMethods;
3540  FilteredMethods.push_back(BestMethod);
3541 
3542  for (auto *M : Methods)
3543  if (M != BestMethod && !M->hasAttr<UnavailableAttr>())
3544  FilteredMethods.push_back(M);
3545 
3546  if (FilteredMethods.size() > 1)
3547  DiagnoseMultipleMethodInGlobalPool(FilteredMethods, Sel, R,
3548  receiverIdOrClass);
3549 
3550  GlobalMethodPool::iterator Pos = MethodPool.find(Sel);
3551  // Test for no method in the pool which should not trigger any warning by
3552  // caller.
3553  if (Pos == MethodPool.end())
3554  return true;
3555  ObjCMethodList &MethList =
3556  BestMethod->isInstanceMethod() ? Pos->second.first : Pos->second.second;
3557  return MethList.hasMoreThanOneDecl();
3558 }
3559 
3560 ObjCMethodDecl *Sema::LookupMethodInGlobalPool(Selector Sel, SourceRange R,
3561  bool receiverIdOrClass,
3562  bool instance) {
3563  if (ExternalSource)
3564  ReadMethodPool(Sel);
3565 
3566  GlobalMethodPool::iterator Pos = MethodPool.find(Sel);
3567  if (Pos == MethodPool.end())
3568  return nullptr;
3569 
3570  // Gather the non-hidden methods.
3571  ObjCMethodList &MethList = instance ? Pos->second.first : Pos->second.second;
3573  for (ObjCMethodList *M = &MethList; M; M = M->getNext()) {
3574  if (M->getMethod() && M->getMethod()->isUnconditionallyVisible())
3575  return M->getMethod();
3576  }
3577  return nullptr;
3578 }
3579 
3581  Selector Sel, SourceRange R,
3582  bool receiverIdOrClass) {
3583  // We found multiple methods, so we may have to complain.
3584  bool issueDiagnostic = false, issueError = false;
3585 
3586  // We support a warning which complains about *any* difference in
3587  // method signature.
3588  bool strictSelectorMatch =
3589  receiverIdOrClass &&
3590  !Diags.isIgnored(diag::warn_strict_multiple_method_decl, R.getBegin());
3591  if (strictSelectorMatch) {
3592  for (unsigned I = 1, N = Methods.size(); I != N; ++I) {
3593  if (!MatchTwoMethodDeclarations(Methods[0], Methods[I], MMS_strict)) {
3594  issueDiagnostic = true;
3595  break;
3596  }
3597  }
3598  }
3599 
3600  // If we didn't see any strict differences, we won't see any loose
3601  // differences. In ARC, however, we also need to check for loose
3602  // mismatches, because most of them are errors.
3603  if (!strictSelectorMatch ||
3604  (issueDiagnostic && getLangOpts().ObjCAutoRefCount))
3605  for (unsigned I = 1, N = Methods.size(); I != N; ++I) {
3606  // This checks if the methods differ in type mismatch.
3607  if (!MatchTwoMethodDeclarations(Methods[0], Methods[I], MMS_loose) &&
3608  !isAcceptableMethodMismatch(Methods[0], Methods[I])) {
3609  issueDiagnostic = true;
3610  if (getLangOpts().ObjCAutoRefCount)
3611  issueError = true;
3612  break;
3613  }
3614  }
3615 
3616  if (issueDiagnostic) {
3617  if (issueError)
3618  Diag(R.getBegin(), diag::err_arc_multiple_method_decl) << Sel << R;
3619  else if (strictSelectorMatch)
3620  Diag(R.getBegin(), diag::warn_strict_multiple_method_decl) << Sel << R;
3621  else
3622  Diag(R.getBegin(), diag::warn_multiple_method_decl) << Sel << R;
3623 
3624  Diag(Methods[0]->getBeginLoc(),
3625  issueError ? diag::note_possibility : diag::note_using)
3626  << Methods[0]->getSourceRange();
3627  for (unsigned I = 1, N = Methods.size(); I != N; ++I) {
3628  Diag(Methods[I]->getBeginLoc(), diag::note_also_found)
3629  << Methods[I]->getSourceRange();
3630  }
3631  }
3632 }
3633 
3635  GlobalMethodPool::iterator Pos = MethodPool.find(Sel);
3636  if (Pos == MethodPool.end())
3637  return nullptr;
3638 
3639  GlobalMethods &Methods = Pos->second;
3640  for (const ObjCMethodList *Method = &Methods.first; Method;
3641  Method = Method->getNext())
3642  if (Method->getMethod() &&
3643  (Method->getMethod()->isDefined() ||
3644  Method->getMethod()->isPropertyAccessor()))
3645  return Method->getMethod();
3646 
3647  for (const ObjCMethodList *Method = &Methods.second; Method;
3648  Method = Method->getNext())
3649  if (Method->getMethod() &&
3650  (Method->getMethod()->isDefined() ||
3651  Method->getMethod()->isPropertyAccessor()))
3652  return Method->getMethod();
3653  return nullptr;
3654 }
3655 
3656 static void
3659  StringRef Typo, const ObjCMethodDecl * Method) {
3660  const unsigned MaxEditDistance = 1;
3661  unsigned BestEditDistance = MaxEditDistance + 1;
3662  std::string MethodName = Method->getSelector().getAsString();
3663 
3664  unsigned MinPossibleEditDistance = abs((int)MethodName.size() - (int)Typo.size());
3665  if (MinPossibleEditDistance > 0 &&
3666  Typo.size() / MinPossibleEditDistance < 1)
3667  return;
3668  unsigned EditDistance = Typo.edit_distance(MethodName, true, MaxEditDistance);
3669  if (EditDistance > MaxEditDistance)
3670  return;
3671  if (EditDistance == BestEditDistance)
3672  BestMethod.push_back(Method);
3673  else if (EditDistance < BestEditDistance) {
3674  BestMethod.clear();
3675  BestMethod.push_back(Method);
3676  }
3677 }
3678 
3680  QualType ObjectType) {
3681  if (ObjectType.isNull())
3682  return true;
3683  if (S.LookupMethodInObjectType(Sel, ObjectType, true/*Instance method*/))
3684  return true;
3685  return S.LookupMethodInObjectType(Sel, ObjectType, false/*Class method*/) !=
3686  nullptr;
3687 }
3688 
3689 const ObjCMethodDecl *
3691  QualType ObjectType) {
3692  unsigned NumArgs = Sel.getNumArgs();
3694  bool ObjectIsId = true, ObjectIsClass = true;
3695  if (ObjectType.isNull())
3696  ObjectIsId = ObjectIsClass = false;
3697  else if (!ObjectType->isObjCObjectPointerType())
3698  return nullptr;
3699  else if (const ObjCObjectPointerType *ObjCPtr =
3700  ObjectType->getAsObjCInterfacePointerType()) {
3701  ObjectType = QualType(ObjCPtr->getInterfaceType(), 0);
3702  ObjectIsId = ObjectIsClass = false;
3703  }
3704  else if (ObjectType->isObjCIdType() || ObjectType->isObjCQualifiedIdType())
3705  ObjectIsClass = false;
3706  else if (ObjectType->isObjCClassType() || ObjectType->isObjCQualifiedClassType())
3707  ObjectIsId = false;
3708  else
3709  return nullptr;
3710 
3711  for (GlobalMethodPool::iterator b = MethodPool.begin(),
3712  e = MethodPool.end(); b != e; b++) {
3713  // instance methods
3714  for (ObjCMethodList *M = &b->second.first; M; M=M->getNext())
3715  if (M->getMethod() &&
3716  (M->getMethod()->getSelector().getNumArgs() == NumArgs) &&
3717  (M->getMethod()->getSelector() != Sel)) {
3718  if (ObjectIsId)
3719  Methods.push_back(M->getMethod());
3720  else if (!ObjectIsClass &&
3721  HelperIsMethodInObjCType(*this, M->getMethod()->getSelector(),
3722  ObjectType))
3723  Methods.push_back(M->getMethod());
3724  }
3725  // class methods
3726  for (ObjCMethodList *M = &b->second.second; M; M=M->getNext())
3727  if (M->getMethod() &&
3728  (M->getMethod()->getSelector().getNumArgs() == NumArgs) &&
3729  (M->getMethod()->getSelector() != Sel)) {
3730  if (ObjectIsClass)
3731  Methods.push_back(M->getMethod());
3732  else if (!ObjectIsId &&
3733  HelperIsMethodInObjCType(*this, M->getMethod()->getSelector(),
3734  ObjectType))
3735  Methods.push_back(M->getMethod());
3736  }
3737  }
3738 
3740  for (unsigned i = 0, e = Methods.size(); i < e; i++) {
3741  HelperSelectorsForTypoCorrection(SelectedMethods,
3742  Sel.getAsString(), Methods[i]);
3743  }
3744  return (SelectedMethods.size() == 1) ? SelectedMethods[0] : nullptr;
3745 }
3746 
3747 /// DiagnoseDuplicateIvars -
3748 /// Check for duplicate ivars in the entire class at the start of
3749 /// \@implementation. This becomes necesssary because class extension can
3750 /// add ivars to a class in random order which will not be known until
3751 /// class's \@implementation is seen.
3753  ObjCInterfaceDecl *SID) {
3754  for (auto *Ivar : ID->ivars()) {
3755  if (Ivar->isInvalidDecl())
3756  continue;
3757  if (IdentifierInfo *II = Ivar->getIdentifier()) {
3758  ObjCIvarDecl* prevIvar = SID->lookupInstanceVariable(II);
3759  if (prevIvar) {
3760  Diag(Ivar->getLocation(), diag::err_duplicate_member) << II;
3761  Diag(prevIvar->getLocation(), diag::note_previous_declaration);
3762  Ivar->setInvalidDecl();
3763  }
3764  }
3765  }
3766 }
3767 
3768 /// Diagnose attempts to define ARC-__weak ivars when __weak is disabled.
3770  if (S.getLangOpts().ObjCWeak) return;
3771 
3772  for (auto ivar = ID->getClassInterface()->all_declared_ivar_begin();
3773  ivar; ivar = ivar->getNextIvar()) {
3774  if (ivar->isInvalidDecl()) continue;
3775  if (ivar->getType().getObjCLifetime() == Qualifiers::OCL_Weak) {
3776  if (S.getLangOpts().ObjCWeakRuntime) {
3777  S.Diag(ivar->getLocation(), diag::err_arc_weak_disabled);
3778  } else {
3779  S.Diag(ivar->getLocation(), diag::err_arc_weak_no_runtime);
3780  }
3781  }
3782  }
3783 }
3784 
3785 /// Diagnose attempts to use flexible array member with retainable object type.
3787  ObjCInterfaceDecl *ID) {
3788  if (!S.getLangOpts().ObjCAutoRefCount)
3789  return;
3790 
3791  for (auto ivar = ID->all_declared_ivar_begin(); ivar;
3792  ivar = ivar->getNextIvar()) {
3793  if (ivar->isInvalidDecl())
3794  continue;
3795  QualType IvarTy = ivar->getType();
3796  if (IvarTy->isIncompleteArrayType() &&
3798  IvarTy->isObjCLifetimeType()) {
3799  S.Diag(ivar->getLocation(), diag::err_flexible_array_arc_retainable);
3800  ivar->setInvalidDecl();
3801  }
3802  }
3803 }
3804 
3806  switch (CurContext->getDeclKind()) {
3807  case Decl::ObjCInterface:
3808  return Sema::OCK_Interface;
3809  case Decl::ObjCProtocol:
3810  return Sema::OCK_Protocol;
3811  case Decl::ObjCCategory:
3812  if (cast<ObjCCategoryDecl>(CurContext)->IsClassExtension())
3813  return Sema::OCK_ClassExtension;
3814  return Sema::OCK_Category;
3815  case Decl::ObjCImplementation:
3816  return Sema::OCK_Implementation;
3817  case Decl::ObjCCategoryImpl:
3819 
3820  default:
3821  return Sema::OCK_None;
3822  }
3823 }
3824 
3826  if (T->isIncompleteArrayType())
3827  return true;
3828  const auto *RecordTy = T->getAs<RecordType>();
3829  return (RecordTy && RecordTy->getDecl()->hasFlexibleArrayMember());
3830 }
3831 
3833  ObjCInterfaceDecl *IntfDecl = nullptr;
3834  ObjCInterfaceDecl::ivar_range Ivars = llvm::make_range(
3836  if ((IntfDecl = dyn_cast<ObjCInterfaceDecl>(OCD))) {
3837  Ivars = IntfDecl->ivars();
3838  } else if (auto *ImplDecl = dyn_cast<ObjCImplementationDecl>(OCD)) {
3839  IntfDecl = ImplDecl->getClassInterface();
3840  Ivars = ImplDecl->ivars();
3841  } else if (auto *CategoryDecl = dyn_cast<ObjCCategoryDecl>(OCD)) {
3842  if (CategoryDecl->IsClassExtension()) {
3843  IntfDecl = CategoryDecl->getClassInterface();
3844  Ivars = CategoryDecl->ivars();
3845  }
3846  }
3847 
3848  // Check if variable sized ivar is in interface and visible to subclasses.
3849  if (!isa<ObjCInterfaceDecl>(OCD)) {
3850  for (auto ivar : Ivars) {
3851  if (!ivar->isInvalidDecl() && IsVariableSizedType(ivar->getType())) {
3852  S.Diag(ivar->getLocation(), diag::warn_variable_sized_ivar_visibility)
3853  << ivar->getDeclName() << ivar->getType();
3854  }
3855  }
3856  }
3857 
3858  // Subsequent checks require interface decl.
3859  if (!IntfDecl)
3860  return;
3861 
3862  // Check if variable sized ivar is followed by another ivar.
3863  for (ObjCIvarDecl *ivar = IntfDecl->all_declared_ivar_begin(); ivar;
3864  ivar = ivar->getNextIvar()) {
3865  if (ivar->isInvalidDecl() || !ivar->getNextIvar())
3866  continue;
3867  QualType IvarTy = ivar->getType();
3868  bool IsInvalidIvar = false;
3869  if (IvarTy->isIncompleteArrayType()) {
3870  S.Diag(ivar->getLocation(), diag::err_flexible_array_not_at_end)
3871  << ivar->getDeclName() << IvarTy
3872  << TTK_Class; // Use "class" for Obj-C.
3873  IsInvalidIvar = true;
3874  } else if (const RecordType *RecordTy = IvarTy->getAs<RecordType>()) {
3875  if (RecordTy->getDecl()->hasFlexibleArrayMember()) {
3876  S.Diag(ivar->getLocation(),
3877  diag::err_objc_variable_sized_type_not_at_end)
3878  << ivar->getDeclName() << IvarTy;
3879  IsInvalidIvar = true;
3880  }
3881  }
3882  if (IsInvalidIvar) {
3883  S.Diag(ivar->getNextIvar()->getLocation(),
3884  diag::note_next_ivar_declaration)
3885  << ivar->getNextIvar()->getSynthesize();
3886  ivar->setInvalidDecl();
3887  }
3888  }
3889 
3890  // Check if ObjC container adds ivars after variable sized ivar in superclass.
3891  // Perform the check only if OCD is the first container to declare ivars to
3892  // avoid multiple warnings for the same ivar.
3893  ObjCIvarDecl *FirstIvar =
3894  (Ivars.begin() == Ivars.end()) ? nullptr : *Ivars.begin();
3895  if (FirstIvar && (FirstIvar == IntfDecl->all_declared_ivar_begin())) {
3896  const ObjCInterfaceDecl *SuperClass = IntfDecl->getSuperClass();
3897  while (SuperClass && SuperClass->ivar_empty())
3898  SuperClass = SuperClass->getSuperClass();
3899  if (SuperClass) {
3900  auto IvarIter = SuperClass->ivar_begin();
3901  std::advance(IvarIter, SuperClass->ivar_size() - 1);
3902  const ObjCIvarDecl *LastIvar = *IvarIter;
3903  if (IsVariableSizedType(LastIvar->getType())) {
3904  S.Diag(FirstIvar->getLocation(),
3905  diag::warn_superclass_variable_sized_type_not_at_end)
3906  << FirstIvar->getDeclName() << LastIvar->getDeclName()
3907  << LastIvar->getType() << SuperClass->getDeclName();
3908  S.Diag(LastIvar->getLocation(), diag::note_entity_declared_at)
3909  << LastIvar->getDeclName();
3910  }
3911  }
3912  }
3913 }
3914 
3916  Sema &S, ObjCProtocolDecl *PDecl, ObjCCategoryDecl *CDecl);
3917 
3919  Sema &S, ObjCCategoryDecl *CDecl,
3920  const llvm::iterator_range<ObjCProtocolList::iterator> &Protocols) {
3921  for (auto *PI : Protocols)
3923 }
3924 
3926  Sema &S, ObjCProtocolDecl *PDecl, ObjCCategoryDecl *CDecl) {
3927  if (!PDecl->isThisDeclarationADefinition() && PDecl->getDefinition())
3928  PDecl = PDecl->getDefinition();
3929 
3930  llvm::SmallVector<const Decl *, 4> DirectMembers;
3931  const auto *IDecl = CDecl->getClassInterface();
3932  for (auto *MD : PDecl->methods()) {
3933  if (!MD->isPropertyAccessor()) {
3934  if (const auto *CMD =
3935  IDecl->getMethod(MD->getSelector(), MD->isInstanceMethod())) {
3936  if (CMD->isDirectMethod())
3937  DirectMembers.push_back(CMD);
3938  }
3939  }
3940  }
3941  for (auto *PD : PDecl->properties()) {
3942  if (const auto *CPD = IDecl->FindPropertyVisibleInPrimaryClass(
3943  PD->getIdentifier(),
3944  PD->isClassProperty()
3947  if (CPD->isDirectProperty())
3948  DirectMembers.push_back(CPD);
3949  }
3950  }
3951  if (!DirectMembers.empty()) {
3952  S.Diag(CDecl->getLocation(), diag::err_objc_direct_protocol_conformance)
3953  << CDecl->IsClassExtension() << CDecl << PDecl << IDecl;
3954  for (const auto *MD : DirectMembers)
3955  S.Diag(MD->getLocation(), diag::note_direct_member_here);
3956  return;
3957  }
3958 
3959  // Check on this protocols's referenced protocols, recursively.
3961  PDecl->protocols());
3962 }
3963 
3964 // Note: For class/category implementations, allMethods is always null.
3966  ArrayRef<DeclGroupPtrTy> allTUVars) {
3968  return nullptr;
3969 
3970  assert(AtEnd.isValid() && "Invalid location for '@end'");
3971 
3972  auto *OCD = cast<ObjCContainerDecl>(CurContext);
3973  Decl *ClassDecl = OCD;
3974 
3975  bool isInterfaceDeclKind =
3976  isa<ObjCInterfaceDecl>(ClassDecl) || isa<ObjCCategoryDecl>(ClassDecl)
3977  || isa<ObjCProtocolDecl>(ClassDecl);
3978  bool checkIdenticalMethods = isa<ObjCImplementationDecl>(ClassDecl);
3979 
3980  // Make synthesized accessor stub functions visible.
3981  // ActOnPropertyImplDecl() creates them as not visible in case
3982  // they are overridden by an explicit method that is encountered
3983  // later.
3984  if (auto *OID = dyn_cast<ObjCImplementationDecl>(CurContext)) {
3985  for (auto PropImpl : OID->property_impls()) {
3986  if (auto *Getter = PropImpl->getGetterMethodDecl())
3987  if (Getter->isSynthesizedAccessorStub())
3988  OID->addDecl(Getter);
3989  if (auto *Setter = PropImpl->getSetterMethodDecl())
3990  if (Setter->isSynthesizedAccessorStub())
3991  OID->addDecl(Setter);
3992  }
3993  }
3994 
3995  // FIXME: Remove these and use the ObjCContainerDecl/DeclContext.
3996  llvm::DenseMap<Selector, const ObjCMethodDecl*> InsMap;
3997  llvm::DenseMap<Selector, const ObjCMethodDecl*> ClsMap;
3998 
3999  for (unsigned i = 0, e = allMethods.size(); i != e; i++ ) {
4000  ObjCMethodDecl *Method =
4001  cast_or_null<ObjCMethodDecl>(allMethods[i]);
4002 
4003  if (!Method) continue; // Already issued a diagnostic.
4004  if (Method->isInstanceMethod()) {
4005  /// Check for instance method of the same name with incompatible types
4006  const ObjCMethodDecl *&PrevMethod = InsMap[Method->getSelector()];
4007  bool match = PrevMethod ? MatchTwoMethodDeclarations(Method, PrevMethod)
4008  : false;
4009  if ((isInterfaceDeclKind && PrevMethod && !match)
4010  || (checkIdenticalMethods && match)) {
4011  Diag(Method->getLocation(), diag::err_duplicate_method_decl)
4012  << Method->getDeclName();
4013  Diag(PrevMethod->getLocation(), diag::note_previous_declaration);
4014  Method->setInvalidDecl();
4015  } else {
4016  if (PrevMethod) {
4017  Method->setAsRedeclaration(PrevMethod);
4019  Method->getLocation()))
4020  Diag(Method->getLocation(), diag::warn_duplicate_method_decl)
4021  << Method->getDeclName();
4022  Diag(PrevMethod->getLocation(), diag::note_previous_declaration);
4023  }
4024  InsMap[Method->getSelector()] = Method;
4025  /// The following allows us to typecheck messages to "id".
4027  }
4028  } else {
4029  /// Check for class method of the same name with incompatible types
4030  const ObjCMethodDecl *&PrevMethod = ClsMap[Method->getSelector()];
4031  bool match = PrevMethod ? MatchTwoMethodDeclarations(Method, PrevMethod)
4032  : false;
4033  if ((isInterfaceDeclKind && PrevMethod && !match)
4034  || (checkIdenticalMethods && match)) {
4035  Diag(Method->getLocation(), diag::err_duplicate_method_decl)
4036  << Method->getDeclName();
4037  Diag(PrevMethod->getLocation(), diag::note_previous_declaration);
4038  Method->setInvalidDecl();
4039  } else {
4040  if (PrevMethod) {
4041  Method->setAsRedeclaration(PrevMethod);
4043  Method->getLocation()))
4044  Diag(Method->getLocation(), diag::warn_duplicate_method_decl)
4045  << Method->getDeclName();
4046  Diag(PrevMethod->getLocation(), diag::note_previous_declaration);
4047  }
4048  ClsMap[Method->getSelector()] = Method;
4050  }
4051  }
4052  }
4053  if (isa<ObjCInterfaceDecl>(ClassDecl)) {
4054  // Nothing to do here.
4055  } else if (ObjCCategoryDecl *C = dyn_cast<ObjCCategoryDecl>(ClassDecl)) {
4056  // Categories are used to extend the class by declaring new methods.
4057  // By the same token, they are also used to add new properties. No
4058  // need to compare the added property to those in the class.
4059 
4060  if (C->IsClassExtension()) {
4061  ObjCInterfaceDecl *CCPrimary = C->getClassInterface();
4062  DiagnoseClassExtensionDupMethods(C, CCPrimary);
4063  }
4064 
4066  }
4067  if (ObjCContainerDecl *CDecl = dyn_cast<ObjCContainerDecl>(ClassDecl)) {
4068  if (CDecl->getIdentifier())
4069  // ProcessPropertyDecl is responsible for diagnosing conflicts with any
4070  // user-defined setter/getter. It also synthesizes setter/getter methods
4071  // and adds them to the DeclContext and global method pools.
4072  for (auto *I : CDecl->properties())
4074  CDecl->setAtEndRange(AtEnd);
4075  }
4076  if (ObjCImplementationDecl *IC=dyn_cast<ObjCImplementationDecl>(ClassDecl)) {
4077  IC->setAtEndRange(AtEnd);
4078  if (ObjCInterfaceDecl* IDecl = IC->getClassInterface()) {
4079  // Any property declared in a class extension might have user
4080  // declared setter or getter in current class extension or one
4081  // of the other class extensions. Mark them as synthesized as
4082  // property will be synthesized when property with same name is
4083  // seen in the @implementation.
4084  for (const auto *Ext : IDecl->visible_extensions()) {
4085  for (const auto *Property : Ext->instance_properties()) {
4086  // Skip over properties declared @dynamic
4087  if (const ObjCPropertyImplDecl *PIDecl
4088  = IC->FindPropertyImplDecl(Property->getIdentifier(),
4089  Property->getQueryKind()))
4090  if (PIDecl->getPropertyImplementation()
4092  continue;
4093 
4094  for (const auto *Ext : IDecl->visible_extensions()) {
4095  if (ObjCMethodDecl *GetterMethod =
4096  Ext->getInstanceMethod(Property->getGetterName()))
4097  GetterMethod->setPropertyAccessor(true);
4098  if (!Property->isReadOnly())
4099  if (ObjCMethodDecl *SetterMethod
4100  = Ext->getInstanceMethod(Property->getSetterName()))
4101  SetterMethod->setPropertyAccessor(true);
4102  }
4103  }
4104  }
4105  ImplMethodsVsClassMethods(S, IC, IDecl);
4109  if (IDecl->hasDesignatedInitializers())
4111  DiagnoseWeakIvars(*this, IC);
4113 
4114  bool HasRootClassAttr = IDecl->hasAttr<ObjCRootClassAttr>();
4115  if (IDecl->getSuperClass() == nullptr) {
4116  // This class has no superclass, so check that it has been marked with
4117  // __attribute((objc_root_class)).
4118  if (!HasRootClassAttr) {
4119  SourceLocation DeclLoc(IDecl->getLocation());
4120  SourceLocation SuperClassLoc(getLocForEndOfToken(DeclLoc));
4121  Diag(DeclLoc, diag::warn_objc_root_class_missing)
4122  << IDecl->getIdentifier();
4123  // See if NSObject is in the current scope, and if it is, suggest
4124  // adding " : NSObject " to the class declaration.
4126  NSAPIObj->getNSClassId(NSAPI::ClassId_NSObject),
4127  DeclLoc, LookupOrdinaryName);
4128  ObjCInterfaceDecl *NSObjectDecl = dyn_cast_or_null<ObjCInterfaceDecl>(IF);
4129  if (NSObjectDecl && NSObjectDecl->getDefinition()) {
4130  Diag(SuperClassLoc, diag::note_objc_needs_superclass)
4131  << FixItHint::CreateInsertion(SuperClassLoc, " : NSObject ");
4132  } else {
4133  Diag(SuperClassLoc, diag::note_objc_needs_superclass);
4134  }
4135  }
4136  } else if (HasRootClassAttr) {
4137  // Complain that only root classes may have this attribute.
4138  Diag(IDecl->getLocation(), diag::err_objc_root_class_subclass);
4139  }
4140 
4141  if (const ObjCInterfaceDecl *Super = IDecl->getSuperClass()) {
4142  // An interface can subclass another interface with a
4143  // objc_subclassing_restricted attribute when it has that attribute as
4144  // well (because of interfaces imported from Swift). Therefore we have
4145  // to check if we can subclass in the implementation as well.
4146  if (IDecl->hasAttr<ObjCSubclassingRestrictedAttr>() &&
4147  Super->hasAttr<ObjCSubclassingRestrictedAttr>()) {
4148  Diag(IC->getLocation(), diag::err_restricted_superclass_mismatch);
4149  Diag(Super->getLocation(), diag::note_class_declared);
4150  }
4151  }
4152 
4153  if (IDecl->hasAttr<ObjCClassStubAttr>())
4154  Diag(IC->getLocation(), diag::err_implementation_of_class_stub);
4155 
4157  while (IDecl->getSuperClass()) {
4158  DiagnoseDuplicateIvars(IDecl, IDecl->getSuperClass());
4159  IDecl = IDecl->getSuperClass();
4160  }
4161  }
4162  }
4163  SetIvarInitializers(IC);
4164  } else if (ObjCCategoryImplDecl* CatImplClass =
4165  dyn_cast<ObjCCategoryImplDecl>(ClassDecl)) {
4166  CatImplClass->setAtEndRange(AtEnd);
4167 
4168  // Find category interface decl and then check that all methods declared
4169  // in this interface are implemented in the category @implementation.
4170  if (ObjCInterfaceDecl* IDecl = CatImplClass->getClassInterface()) {
4171  if (ObjCCategoryDecl *Cat
4172  = IDecl->FindCategoryDeclaration(CatImplClass->getIdentifier())) {
4173  ImplMethodsVsClassMethods(S, CatImplClass, Cat);
4174  }
4175  }
4176  } else if (const auto *IntfDecl = dyn_cast<ObjCInterfaceDecl>(ClassDecl)) {
4177  if (const ObjCInterfaceDecl *Super = IntfDecl->getSuperClass()) {
4178  if (!IntfDecl->hasAttr<ObjCSubclassingRestrictedAttr>() &&
4179  Super->hasAttr<ObjCSubclassingRestrictedAttr>()) {
4180  Diag(IntfDecl->getLocation(), diag::err_restricted_superclass_mismatch);
4181  Diag(Super->getLocation(), diag::note_class_declared);
4182  }
4183  }
4184 
4185  if (IntfDecl->hasAttr<ObjCClassStubAttr>() &&
4186  !IntfDecl->hasAttr<ObjCSubclassingRestrictedAttr>())
4187  Diag(IntfDecl->getLocation(), diag::err_class_stub_subclassing_mismatch);
4188  }
4189  DiagnoseVariableSizedIvars(*this, OCD);
4190  if (isInterfaceDeclKind) {
4191  // Reject invalid vardecls.
4192  for (unsigned i = 0, e = allTUVars.size(); i != e; i++) {
4193  DeclGroupRef DG = allTUVars[i].get();
4194  for (DeclGroupRef::iterator I = DG.begin(), E = DG.end(); I != E; ++I)
4195  if (VarDecl *VDecl = dyn_cast<VarDecl>(*I)) {
4196  if (!VDecl->hasExternalStorage())
4197  Diag(VDecl->getLocation(), diag::err_objc_var_decl_inclass);
4198  }
4199  }
4200  }
4202 
4203  for (unsigned i = 0, e = allTUVars.size(); i != e; i++) {
4204  DeclGroupRef DG = allTUVars[i].get();
4205  for (DeclGroupRef::iterator I = DG.begin(), E = DG.end(); I != E; ++I)
4206  (*I)->setTopLevelDeclInObjCContainer();
4208  }
4209 
4210  ActOnDocumentableDecl(ClassDecl);
4211  return ClassDecl;
4212 }
4213 
4214 /// CvtQTToAstBitMask - utility routine to produce an AST bitmask for
4215 /// objective-c's type qualifier from the parser version of the same info.
4218  return (Decl::ObjCDeclQualifier) (unsigned) PQTVal;
4219 }
4220 
4221 /// Check whether the declared result type of the given Objective-C
4222 /// method declaration is compatible with the method's class.
4223 ///
4226  ObjCInterfaceDecl *CurrentClass) {
4227  QualType ResultType = Method->getReturnType();
4228 
4229  // If an Objective-C method inherits its related result type, then its
4230  // declared result type must be compatible with its own class type. The
4231  // declared result type is compatible if:
4232  if (const ObjCObjectPointerType *ResultObjectType
4233  = ResultType->getAs<ObjCObjectPointerType>()) {
4234  // - it is id or qualified id, or
4235  if (ResultObjectType->isObjCIdType() ||
4236  ResultObjectType->isObjCQualifiedIdType())
4237  return Sema::RTC_Compatible;
4238 
4239  if (CurrentClass) {
4240  if (ObjCInterfaceDecl *ResultClass
4241  = ResultObjectType->getInterfaceDecl()) {
4242  // - it is the same as the method's class type, or
4243  if (declaresSameEntity(CurrentClass, ResultClass))
4244  return Sema::RTC_Compatible;
4245 
4246  // - it is a superclass of the method's class type
4247  if (ResultClass->isSuperClassOf(CurrentClass))
4248  return Sema::RTC_Compatible;
4249  }
4250  } else {
4251  // Any Objective-C pointer type might be acceptable for a protocol
4252  // method; we just don't know.
4253  return Sema::RTC_Unknown;
4254  }
4255  }
4256 
4257  return Sema::RTC_Incompatible;
4258 }
4259 
4260 namespace {
4261 /// A helper class for searching for methods which a particular method
4262 /// overrides.
4263 class OverrideSearch {
4264 public:
4265  const ObjCMethodDecl *Method;
4267  bool Recursive;
4268 
4269 public:
4270  OverrideSearch(Sema &S, const ObjCMethodDecl *method) : Method(method) {
4271  Selector selector = method->getSelector();
4272 
4273  // Bypass this search if we've never seen an instance/class method
4274  // with this selector before.
4275  Sema::GlobalMethodPool::iterator it = S.MethodPool.find(selector);
4276  if (it == S.MethodPool.end()) {
4277  if (!S.getExternalSource()) return;
4278  S.ReadMethodPool(selector);
4279 
4280  it = S.MethodPool.find(selector);
4281  if (it == S.MethodPool.end())
4282  return;
4283  }
4284  const ObjCMethodList &list =
4285  method->isInstanceMethod() ? it->second.first : it->second.second;
4286  if (!list.getMethod()) return;
4287 
4288  const ObjCContainerDecl *container
4289  = cast<ObjCContainerDecl>(method->getDeclContext());
4290 
4291  // Prevent the search from reaching this container again. This is
4292  // important with categories, which override methods from the
4293  // interface and each other.
4294  if (const ObjCCategoryDecl *Category =
4295  dyn_cast<ObjCCategoryDecl>(container)) {
4296  searchFromContainer(container);
4297  if (const ObjCInterfaceDecl *Interface = Category->getClassInterface())
4298  searchFromContainer(Interface);
4299  } else {
4300  searchFromContainer(container);
4301  }
4302  }
4303 
4304  typedef decltype(Overridden)::iterator iterator;
4305  iterator begin() const { return Overridden.begin(); }
4306  iterator end() const { return Overridden.end(); }
4307 
4308 private:
4309  void searchFromContainer(const ObjCContainerDecl *container) {
4310  if (container->isInvalidDecl()) return;
4311 
4312  switch (container->getDeclKind()) {
4313 #define OBJCCONTAINER(type, base) \
4314  case Decl::type: \
4315  searchFrom(cast<type##Decl>(container)); \
4316  break;
4317 #define ABSTRACT_DECL(expansion)
4318 #define DECL(type, base) \
4319  case Decl::type:
4320 #include "clang/AST/DeclNodes.inc"
4321  llvm_unreachable("not an ObjC container!");
4322  }
4323  }
4324 
4325  void searchFrom(const ObjCProtocolDecl *protocol) {
4326  if (!protocol->hasDefinition())
4327  return;
4328 
4329  // A method in a protocol declaration overrides declarations from
4330  // referenced ("parent") protocols.
4331  search(protocol->getReferencedProtocols());
4332  }
4333 
4334  void searchFrom(const ObjCCategoryDecl *category) {
4335  // A method in a category declaration overrides declarations from
4336  // the main class and from protocols the category references.
4337  // The main class is handled in the constructor.
4338  search(category->getReferencedProtocols());
4339  }
4340 
4341  void searchFrom(const ObjCCategoryImplDecl *impl) {
4342  // A method in a category definition that has a category
4343  // declaration overrides declarations from the category
4344  // declaration.
4345  if (ObjCCategoryDecl *category = impl->getCategoryDecl()) {
4346  search(category);
4347  if (ObjCInterfaceDecl *Interface = category->getClassInterface())
4348  search(Interface);
4349 
4350  // Otherwise it overrides declarations from the class.
4351  } else if (const auto *Interface = impl->getClassInterface()) {
4352  search(Interface);
4353  }
4354  }
4355 
4356  void searchFrom(const ObjCInterfaceDecl *iface) {
4357  // A method in a class declaration overrides declarations from
4358  if (!iface->hasDefinition())
4359  return;
4360 
4361  // - categories,
4362  for (auto *Cat : iface->known_categories())
4363  search(Cat);
4364 
4365  // - the super class, and
4366  if (ObjCInterfaceDecl *super = iface->getSuperClass())
4367  search(super);
4368 
4369  // - any referenced protocols.
4370  search(iface->getReferencedProtocols());
4371  }
4372 
4373  void searchFrom(const ObjCImplementationDecl *impl) {
4374  // A method in a class implementation overrides declarations from
4375  // the class interface.
4376  if (const auto *Interface = impl->getClassInterface())
4377  search(Interface);
4378  }
4379 
4380  void search(const ObjCProtocolList &protocols) {
4381  for (const auto *Proto : protocols)
4382  search(Proto);
4383  }
4384 
4385  void search(const ObjCContainerDecl *container) {
4386  // Check for a method in this container which matches this selector.
4387  ObjCMethodDecl *meth = container->getMethod(Method->getSelector(),
4388  Method->isInstanceMethod(),
4389  /*AllowHidden=*/true);
4390 
4391  // If we find one, record it and bail out.
4392  if (meth) {
4393  Overridden.insert(meth);
4394  return;
4395  }
4396 
4397  // Otherwise, search for methods that a hypothetical method here
4398  // would have overridden.
4399 
4400  // Note that we're now in a recursive case.
4401  Recursive = true;
4402 
4403  searchFromContainer(container);
4404  }
4405 };
4406 } // end anonymous namespace
4407 
4409  ObjCMethodDecl *overridden) {
4410  if (const auto *attr = overridden->getAttr<ObjCDirectAttr>()) {
4411  Diag(method->getLocation(), diag::err_objc_override_direct_method);
4412  Diag(attr->getLocation(), diag::note_previous_declaration);
4413  } else if (const auto *attr = method->getAttr<ObjCDirectAttr>()) {
4414  Diag(attr->getLocation(), diag::err_objc_direct_on_override)
4415  << isa<ObjCProtocolDecl>(overridden->getDeclContext());
4416  Diag(overridden->getLocation(), diag::note_previous_declaration);
4417  }
4418 }
4419 
4421  ObjCInterfaceDecl *CurrentClass,
4423  if (!ObjCMethod)
4424  return;
4425  // Search for overridden methods and merge information down from them.
4426  OverrideSearch overrides(*this, ObjCMethod);
4427  // Keep track if the method overrides any method in the class's base classes,
4428  // its protocols, or its categories' protocols; we will keep that info
4429  // in the ObjCMethodDecl.
4430  // For this info, a method in an implementation is not considered as
4431  // overriding the same method in the interface or its categories.
4432  bool hasOverriddenMethodsInBaseOrProtocol = false;
4433  for (ObjCMethodDecl *overridden : overrides) {
4434  if (!hasOverriddenMethodsInBaseOrProtocol) {
4435  if (isa<ObjCProtocolDecl>(overridden->getDeclContext()) ||
4436  CurrentClass != overridden->getClassInterface() ||
4437  overridden->isOverriding()) {
4438  CheckObjCMethodDirectOverrides(ObjCMethod, overridden);
4439  hasOverriddenMethodsInBaseOrProtocol = true;
4440  } else if (isa<ObjCImplDecl>(ObjCMethod->getDeclContext())) {
4441  // OverrideSearch will return as "overridden" the same method in the
4442  // interface. For hasOverriddenMethodsInBaseOrProtocol, we need to
4443  // check whether a category of a base class introduced a method with the
4444  // same selector, after the interface method declaration.
4445  // To avoid unnecessary lookups in the majority of cases, we use the
4446  // extra info bits in GlobalMethodPool to check whether there were any
4447  // category methods with this selector.
4448  GlobalMethodPool::iterator It =
4449  MethodPool.find(ObjCMethod->getSelector());
4450  if (It != MethodPool.end()) {
4451  ObjCMethodList &List =
4452  ObjCMethod->isInstanceMethod()? It->second.first: It->second.second;
4453  unsigned CategCount = List.getBits();
4454  if (CategCount > 0) {
4455  // If the method is in a category we'll do lookup if there were at
4456  // least 2 category methods recorded, otherwise only one will do.
4457  if (CategCount > 1 ||
4458  !isa<ObjCCategoryImplDecl>(overridden->getDeclContext())) {
4459  OverrideSearch overrides(*this, overridden);
4460  for (ObjCMethodDecl *SuperOverridden : overrides) {
4461  if (isa<ObjCProtocolDecl>(SuperOverridden->getDeclContext()) ||
4462  CurrentClass != SuperOverridden->getClassInterface()) {
4463  CheckObjCMethodDirectOverrides(ObjCMethod, SuperOverridden);
4464  hasOverriddenMethodsInBaseOrProtocol = true;
4465  overridden->setOverriding(true);
4466  break;
4467  }
4468  }
4469  }
4470  }
4471  }
4472  }
4473  }
4474 
4475  // Propagate down the 'related result type' bit from overridden methods.
4476  if (RTC != Sema::RTC_Incompatible && overridden->hasRelatedResultType())
4477  ObjCMethod->setRelatedResultType();
4478 
4479  // Then merge the declarations.
4480  mergeObjCMethodDecls(ObjCMethod, overridden);
4481 
4482  if (ObjCMethod->isImplicit() && overridden->isImplicit())
4483  continue; // Conflicting properties are detected elsewhere.
4484 
4485  // Check for overriding methods
4486  if (isa<ObjCInterfaceDecl>(ObjCMethod->getDeclContext()) ||
4487  isa<ObjCImplementationDecl>(ObjCMethod->getDeclContext()))
4488  CheckConflictingOverridingMethod(ObjCMethod, overridden,
4489  isa<ObjCProtocolDecl>(overridden->getDeclContext()));
4490 
4491  if (CurrentClass && overridden->getDeclContext() != CurrentClass &&
4492  isa<ObjCInterfaceDecl>(overridden->getDeclContext()) &&
4493  !overridden->isImplicit() /* not meant for properties */) {
4494  ObjCMethodDecl::param_iterator ParamI = ObjCMethod->param_begin(),
4495  E = ObjCMethod->param_end();
4496  ObjCMethodDecl::param_iterator PrevI = overridden->param_begin(),
4497  PrevE = overridden->param_end();
4498  for (; ParamI != E && PrevI != PrevE; ++ParamI, ++PrevI) {
4499  assert(PrevI != overridden->param_end() && "Param mismatch");
4500  QualType T1 = Context.getCanonicalType((*ParamI)->getType());
4501  QualType T2 = Context.getCanonicalType((*PrevI)->getType());
4502  // If type of argument of method in this class does not match its
4503  // respective argument type in the super class method, issue warning;
4504  if (!Context.typesAreCompatible(T1, T2)) {
4505  Diag((*ParamI)->getLocation(), diag::ext_typecheck_base_super)
4506  << T1 << T2;
4507  Diag(overridden->getLocation(), diag::note_previous_declaration);
4508  break;
4509  }
4510  }
4511  }
4512  }
4513 
4514  ObjCMethod->setOverriding(hasOverriddenMethodsInBaseOrProtocol);
4515 }
4516 
4517 /// Merge type nullability from for a redeclaration of the same entity,
4518 /// producing the updated type of the redeclared entity.
4520  QualType type,
4521  bool usesCSKeyword,
4522  SourceLocation prevLoc,
4523  QualType prevType,
4524  bool prevUsesCSKeyword) {
4525  // Determine the nullability of both types.
4526  auto nullability = type->getNullability(S.Context);
4527  auto prevNullability = prevType->getNullability(S.Context);
4528 
4529  // Easy case: both have nullability.
4530  if (nullability.hasValue() == prevNullability.hasValue()) {
4531  // Neither has nullability; continue.
4532  if (!nullability)
4533  return type;
4534 
4535  // The nullabilities are equivalent; do nothing.
4536  if (*nullability == *prevNullability)
4537  return type;
4538 
4539  // Complain about mismatched nullability.
4540  S.Diag(loc, diag::err_nullability_conflicting)
4541  << DiagNullabilityKind(*nullability, usesCSKeyword)
4542  << DiagNullabilityKind(*prevNullability, prevUsesCSKeyword);
4543  return type;
4544  }
4545 
4546  // If it's the redeclaration that has nullability, don't change anything.
4547  if (nullability)
4548  return type;
4549 
4550  // Otherwise, provide the result with the same nullability.
4551  return S.Context.getAttributedType(
4552  AttributedType::getNullabilityAttrKind(*prevNullability),
4553  type, type);
4554 }
4555 
4556 /// Merge information from the declaration of a method in the \@interface
4557 /// (or a category/extension) into the corresponding method in the
4558 /// @implementation (for a class or category).
4560  ObjCMethodDecl *method,
4561  ObjCMethodDecl *prevMethod) {
4562  // Merge the objc_requires_super attribute.
4563  if (prevMethod->hasAttr<ObjCRequiresSuperAttr>() &&
4564  !method->hasAttr<ObjCRequiresSuperAttr>()) {
4565  // merge the attribute into implementation.
4566  method->addAttr(
4567  ObjCRequiresSuperAttr::CreateImplicit(S.Context,
4568  method->getLocation()));
4569  }
4570 
4571  // Merge nullability of the result type.
4572  QualType newReturnType
4574  S, method->getReturnTypeSourceRange().getBegin(),
4575  method->getReturnType(),
4577  prevMethod->getReturnTypeSourceRange().getBegin(),
4578  prevMethod->getReturnType(),
4580  method->setReturnType(newReturnType);
4581 
4582  // Handle each of the parameters.
4583  unsigned numParams = method->param_size();
4584  unsigned numPrevParams = prevMethod->param_size();
4585  for (unsigned i = 0, n = std::min(numParams, numPrevParams); i != n; ++i) {
4586  ParmVarDecl *param = method->param_begin()[i];
4587  ParmVarDecl *prevParam = prevMethod->param_begin()[i];
4588 
4589  // Merge nullability.
4590  QualType newParamType
4592  S, param->getLocation(), param->getType(),
4594  prevParam->getLocation(), prevParam->getType(),
4596  param->setType(newParamType);
4597  }
4598 }
4599 
4600 /// Verify that the method parameters/return value have types that are supported
4601 /// by the x86 target.
4603  const ObjCMethodDecl *Method) {
4604  assert(SemaRef.getASTContext().getTargetInfo().getTriple().getArch() ==
4605  llvm::Triple::x86 &&
4606  "x86-specific check invoked for a different target");
4607  SourceLocation Loc;
4608  QualType T;
4609  for (const ParmVarDecl *P : Method->parameters()) {
4610  if (P->getType()->isVectorType()) {
4611  Loc = P->getBeginLoc();
4612  T = P->getType();
4613  break;
4614  }
4615  }
4616  if (Loc.isInvalid()) {
4617  if (Method->getReturnType()->isVectorType()) {
4618  Loc = Method->getReturnTypeSourceRange().getBegin();
4619  T = Method->getReturnType();
4620  } else
4621  return;
4622  }
4623 
4624  // Vector parameters/return values are not supported by objc_msgSend on x86 in
4625  // iOS < 9 and macOS < 10.11.
4626  const auto &Triple = SemaRef.getASTContext().getTargetInfo().getTriple();
4627  VersionTuple AcceptedInVersion;
4628  if (Triple.getOS() == llvm::Triple::IOS)
4629  AcceptedInVersion = VersionTuple(/*Major=*/9);
4630  else if (Triple.isMacOSX())
4631  AcceptedInVersion = VersionTuple(/*Major=*/10, /*Minor=*/11);
4632  else
4633  return;
4635  AcceptedInVersion)
4636  return;
4637  SemaRef.Diag(Loc, diag::err_objc_method_unsupported_param_ret_type)
4638  << T << (Method->getReturnType()->isVectorType() ? /*return value*/ 1
4639  : /*parameter*/ 0)
4640  << (Triple.isMacOSX() ? "macOS 10.11" : "iOS 9");
4641 }
4642 
4643 static void mergeObjCDirectMembers(Sema &S, Decl *CD, ObjCMethodDecl *Method) {
4644  if (!Method->isDirectMethod() && !Method->hasAttr<UnavailableAttr>() &&
4645  CD->hasAttr<ObjCDirectMembersAttr>()) {
4646  Method->addAttr(
4647  ObjCDirectAttr::CreateImplicit(S.Context, Method->getLocation()));
4648  }
4649 }
4650 
4652  ObjCMethodDecl *Method,
4653  ObjCImplDecl *ImpDecl = nullptr) {
4654  auto Sel = Method->getSelector();
4655  bool isInstance = Method->isInstanceMethod();
4656  bool diagnosed = false;
4657 
4658  auto diagClash = [&](const ObjCMethodDecl *IMD) {
4659  if (diagnosed || IMD->isImplicit())
4660  return;
4661  if (Method->isDirectMethod() || IMD->isDirectMethod()) {
4662  S.Diag(Method->getLocation(), diag::err_objc_direct_duplicate_decl)
4663  << Method->isDirectMethod() << /* method */ 0 << IMD->isDirectMethod()
4664  << Method->getDeclName();
4665  S.Diag(IMD->getLocation(), diag::note_previous_declaration);
4666  diagnosed = true;
4667  }
4668  };
4669 
4670  // Look for any other declaration of this method anywhere we can see in this
4671  // compilation unit.
4672  //
4673  // We do not use IDecl->lookupMethod() because we have specific needs:
4674  //
4675  // - we absolutely do not need to walk protocols, because
4676  // diag::err_objc_direct_on_protocol has already been emitted
4677  // during parsing if there's a conflict,
4678  //
4679  // - when we do not find a match in a given @interface container,
4680  // we need to attempt looking it up in the @implementation block if the
4681  // translation unit sees it to find more clashes.
4682 
4683  if (auto *IMD = IDecl->getMethod(Sel, isInstance))
4684  diagClash(IMD);
4685  else if (auto *Impl = IDecl->getImplementation())
4686  if (Impl != ImpDecl)
4687  if (auto *IMD = IDecl->getImplementation()->getMethod(Sel, isInstance))
4688  diagClash(IMD);
4689 
4690  for (const auto *Cat : IDecl->visible_categories())
4691  if (auto *IMD = Cat->getMethod(Sel, isInstance))
4692  diagClash(IMD);
4693  else if (auto CatImpl = Cat->getImplementation())
4694  if (CatImpl != ImpDecl)
4695  if (auto *IMD = Cat->getMethod(Sel, isInstance))
4696  diagClash(IMD);
4697 }
4698 
4700  Scope *S, SourceLocation MethodLoc, SourceLocation EndLoc,
4701  tok::TokenKind MethodType, ObjCDeclSpec &ReturnQT, ParsedType ReturnType,
4702  ArrayRef<SourceLocation> SelectorLocs, Selector Sel,
4703  // optional arguments. The number of types/arguments is obtained
4704  // from the Sel.getNumArgs().
4705  ObjCArgInfo *ArgInfo, DeclaratorChunk::ParamInfo *CParamInfo,
4706  unsigned CNumArgs, // c-style args
4707  const ParsedAttributesView &AttrList, tok::ObjCKeywordKind MethodDeclKind,
4708  bool isVariadic, bool MethodDefinition) {
4709  // Make sure we can establish a context for the method.
4710  if (!CurContext->isObjCContainer()) {
4711  Diag(MethodLoc, diag::err_missing_method_context);
4712  return nullptr;
4713  }
4714 
4715  Decl *ClassDecl = cast<ObjCContainerDecl>(CurContext);
4716  QualType resultDeclType;
4717 
4718  bool HasRelatedResultType = false;
4719  TypeSourceInfo *ReturnTInfo = nullptr;
4720  if (ReturnType) {
4721  resultDeclType = GetTypeFromParser(ReturnType, &ReturnTInfo);
4722 
4723  if (CheckFunctionReturnType(resultDeclType, MethodLoc))
4724  return nullptr;
4725 
4726  QualType bareResultType = resultDeclType;
4727  (void)AttributedType::stripOuterNullability(bareResultType);
4728  HasRelatedResultType = (bareResultType == Context.getObjCInstanceType());
4729  } else { // get the type for "id".
4730  resultDeclType = Context.getObjCIdType();
4731  Diag(MethodLoc, diag::warn_missing_method_return_type)
4732  << FixItHint::CreateInsertion(SelectorLocs.front(), "(id)");
4733  }
4734 
4735  ObjCMethodDecl *ObjCMethod = ObjCMethodDecl::Create(
4736  Context, MethodLoc, EndLoc, Sel, resultDeclType, ReturnTInfo, CurContext,
4737  MethodType == tok::minus, isVariadic,
4738  /*isPropertyAccessor=*/false, /*isSynthesizedAccessorStub=*/false,
4739  /*isImplicitlyDeclared=*/false, /*isDefined=*/false,
4740  MethodDeclKind == tok::objc_optional ? ObjCMethodDecl::Optional
4742  HasRelatedResultType);
4743 
4745 
4746  for (unsigned i = 0, e = Sel.getNumArgs(); i != e; ++i) {
4747  QualType ArgType;
4748  TypeSourceInfo *DI;
4749 
4750  if (!ArgInfo[i].Type) {
4751  ArgType = Context.getObjCIdType();
4752  DI = nullptr;
4753  } else {
4754  ArgType = GetTypeFromParser(ArgInfo[i].Type, &DI);
4755  }
4756 
4757  LookupResult R(*this, ArgInfo[i].Name, ArgInfo[i].NameLoc,
4759  LookupName(R, S);
4760  if (R.isSingleResult()) {
4761  NamedDecl *PrevDecl = R.getFoundDecl();
4762  if (S->isDeclScope(PrevDecl)) {
4763  Diag(ArgInfo[i].NameLoc,
4764  (MethodDefinition ? diag::warn_method_param_redefinition
4765  : diag::warn_method_param_declaration))
4766  << ArgInfo[i].Name;
4767  Diag(PrevDecl->getLocation(),
4768  diag::note_previous_declaration);
4769  }
4770  }
4771 
4772  SourceLocation StartLoc = DI
4773  ? DI->getTypeLoc().getBeginLoc()
4774  : ArgInfo[i].NameLoc;
4775 
4776  ParmVarDecl* Param = CheckParameter(ObjCMethod, StartLoc,
4777  ArgInfo[i].NameLoc, ArgInfo[i].Name,
4778  ArgType, DI, SC_None);
4779 
4780  Param->setObjCMethodScopeInfo(i);
4781 
4782  Param->setObjCDeclQualifier(
4783  CvtQTToAstBitMask(ArgInfo[i].DeclSpec.getObjCDeclQualifier()));
4784 
4785  // Apply the attributes to the parameter.
4786  ProcessDeclAttributeList(TUScope, Param, ArgInfo[i].ArgAttrs);
4787  AddPragmaAttributes(TUScope, Param);
4788 
4789  if (Param->hasAttr<BlocksAttr>()) {
4790  Diag(Param->getLocation(), diag::err_block_on_nonlocal);
4791  Param->setInvalidDecl();
4792  }
4793  S->AddDecl(Param);
4794  IdResolver.AddDecl(Param);
4795 
4796  Params.push_back(Param);
4797  }
4798 
4799  for (unsigned i = 0, e = CNumArgs; i != e; ++i) {
4800  ParmVarDecl *Param = cast<ParmVarDecl>(CParamInfo[i].Param);
4801  QualType ArgType = Param->getType();
4802  if (ArgType.isNull())
4803  ArgType = Context.getObjCIdType();
4804  else
4805  // Perform the default array/function conversions (C99 6.7.5.3p[7,8]).
4806  ArgType = Context.getAdjustedParameterType(ArgType);
4807 
4808  Param->setDeclContext(ObjCMethod);
4809  Params.push_back(Param);
4810  }
4811 
4812  ObjCMethod->setMethodParams(Context, Params, SelectorLocs);
4813  ObjCMethod->setObjCDeclQualifier(
4815 
4816  ProcessDeclAttributeList(TUScope, ObjCMethod, AttrList);
4817  AddPragmaAttributes(TUScope, ObjCMethod);
4818 
4819  // Add the method now.
4820  const ObjCMethodDecl *PrevMethod = nullptr;
4821  if (ObjCImplDecl *ImpDecl = dyn_cast<ObjCImplDecl>(ClassDecl)) {
4822  if (MethodType == tok::minus) {
4823  PrevMethod = ImpDecl->getInstanceMethod(Sel);
4824  ImpDecl->addInstanceMethod(ObjCMethod);
4825  } else {
4826  PrevMethod = ImpDecl->getClassMethod(Sel);
4827  ImpDecl->addClassMethod(ObjCMethod);
4828  }
4829 
4830  // If this method overrides a previous @synthesize declaration,
4831  // register it with the property. Linear search through all
4832  // properties here, because the autosynthesized stub hasn't been
4833  // made visible yet, so it can be overriden by a later
4834  // user-specified implementation.
4835  for (ObjCPropertyImplDecl *PropertyImpl : ImpDecl->property_impls()) {
4836  if (auto *Setter = PropertyImpl->getSetterMethodDecl())
4837  if (Setter->getSelector() == Sel &&
4838  Setter->isInstanceMethod() == ObjCMethod->isInstanceMethod()) {
4839  assert(Setter->isSynthesizedAccessorStub() && "autosynth stub expected");
4840  PropertyImpl->setSetterMethodDecl(ObjCMethod);
4841  }
4842  if (auto *Getter = PropertyImpl->getGetterMethodDecl())
4843  if (Getter->getSelector() == Sel &&
4844  Getter->isInstanceMethod() == ObjCMethod->isInstanceMethod()) {
4845  assert(Getter->isSynthesizedAccessorStub() && "autosynth stub expected");
4846  PropertyImpl->setGetterMethodDecl(ObjCMethod);
4847  break;
4848  }
4849  }
4850 
4851  // A method is either tagged direct explicitly, or inherits it from its
4852  // canonical declaration.
4853  //
4854  // We have to do the merge upfront and not in mergeInterfaceMethodToImpl()
4855  // because IDecl->lookupMethod() returns more possible matches than just
4856  // the canonical declaration.
4857  if (!ObjCMethod->isDirectMethod()) {
4858  const ObjCMethodDecl *CanonicalMD = ObjCMethod->getCanonicalDecl();
4859  if (const auto *attr = CanonicalMD->getAttr<ObjCDirectAttr>()) {
4860  ObjCMethod->addAttr(
4861  ObjCDirectAttr::CreateImplicit(Context, attr->getLocation()));
4862  }
4863  }
4864 
4865  // Merge information from the @interface declaration into the
4866  // @implementation.
4867  if (ObjCInterfaceDecl *IDecl = ImpDecl->getClassInterface()) {
4868  if (auto *IMD = IDecl->lookupMethod(ObjCMethod->getSelector(),
4869  ObjCMethod->isInstanceMethod())) {
4870  mergeInterfaceMethodToImpl(*this, ObjCMethod, IMD);
4871 
4872  // The Idecl->lookupMethod() above will find declarations for ObjCMethod
4873  // in one of these places:
4874  //
4875  // (1) the canonical declaration in an @interface container paired
4876  // with the ImplDecl,
4877  // (2) non canonical declarations in @interface not paired with the
4878  // ImplDecl for the same Class,
4879  // (3) any superclass container.
4880  //
4881  // Direct methods only allow for canonical declarations in the matching
4882  // container (case 1).
4883  //
4884  // Direct methods overriding a superclass declaration (case 3) is
4885  // handled during overrides checks in CheckObjCMethodOverrides().
4886  //
4887  // We deal with same-class container mismatches (Case 2) here.
4888  if (IDecl == IMD->getClassInterface()) {
4889  auto diagContainerMismatch = [&] {
4890  int decl = 0, impl = 0;
4891 
4892  if (auto *Cat = dyn_cast<ObjCCategoryDecl>(IMD->getDeclContext()))
4893  decl = Cat->IsClassExtension() ? 1 : 2;
4894 
4895  if (isa<ObjCCategoryImplDecl>(ImpDecl))
4896  impl = 1 + (decl != 0);
4897 
4898  Diag(ObjCMethod->getLocation(),
4899  diag::err_objc_direct_impl_decl_mismatch)
4900  << decl << impl;
4901  Diag(IMD->getLocation(), diag::note_previous_declaration);
4902  };
4903 
4904  if (const auto *attr = ObjCMethod->getAttr<ObjCDirectAttr>()) {
4905  if (ObjCMethod->getCanonicalDecl() != IMD) {
4906  diagContainerMismatch();
4907  } else if (!IMD->isDirectMethod()) {
4908  Diag(attr->getLocation(), diag::err_objc_direct_missing_on_decl);
4909  Diag(IMD->getLocation(), diag::note_previous_declaration);
4910  }
4911  } else if (const auto *attr = IMD->getAttr<ObjCDirectAttr>()) {
4912  if (ObjCMethod->getCanonicalDecl() != IMD) {
4913  diagContainerMismatch();
4914  } else {
4915  ObjCMethod->addAttr(
4916  ObjCDirectAttr::CreateImplicit(Context, attr->getLocation()));
4917  }
4918  }
4919  }
4920 
4921  // Warn about defining -dealloc in a category.
4922  if (isa<ObjCCategoryImplDecl>(ImpDecl) && IMD->isOverriding() &&
4923  ObjCMethod->getSelector().getMethodFamily() == OMF_dealloc) {
4924  Diag(ObjCMethod->getLocation(), diag::warn_dealloc_in_category)
4925  << ObjCMethod->getDeclName();
4926  }
4927  } else {
4928  mergeObjCDirectMembers(*this, ClassDecl, ObjCMethod);
4929  checkObjCDirectMethodClashes(*this, IDecl, ObjCMethod, ImpDecl);
4930  }
4931 
4932  // Warn if a method declared in a protocol to which a category or
4933  // extension conforms is non-escaping and the implementation's method is
4934  // escaping.
4935  for (auto *C : IDecl->visible_categories())
4936  for (auto &P : C->protocols())
4937  if (auto *IMD = P->lookupMethod(ObjCMethod->getSelector(),
4938  ObjCMethod->isInstanceMethod())) {
4939  assert(ObjCMethod->parameters().size() ==
4940  IMD->parameters().size() &&
4941  "Methods have different number of parameters");
4942  auto OI = IMD->param_begin(), OE = IMD->param_end();
4943  auto NI = ObjCMethod->param_begin();
4944  for (; OI != OE; ++OI, ++NI)
4945  diagnoseNoescape(*NI, *OI, C, P, *this);
4946  }
4947  }
4948  } else {
4949  if (!isa<ObjCProtocolDecl>(ClassDecl)) {
4950  mergeObjCDirectMembers(*this, ClassDecl, ObjCMethod);
4951 
4952  ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(ClassDecl);
4953  if (!IDecl)
4954  IDecl = cast<ObjCCategoryDecl>(ClassDecl)->getClassInterface();
4955  // For valid code, we should always know the primary interface
4956  // declaration by now, however for invalid code we'll keep parsing
4957  // but we won't find the primary interface and IDecl will be nil.
4958  if (IDecl)
4959  checkObjCDirectMethodClashes(*this, IDecl, ObjCMethod);
4960  }
4961 
4962  cast<DeclContext>(ClassDecl)->addDecl(ObjCMethod);
4963  }
4964 
4965  if (PrevMethod) {
4966  // You can never have two method definitions with the same name.
4967  Diag(ObjCMethod->getLocation(), diag::err_duplicate_method_decl)
4968  << ObjCMethod->getDeclName();
4969  Diag(PrevMethod->getLocation(), diag::note_previous_declaration);
4970  ObjCMethod->setInvalidDecl();
4971  return ObjCMethod;
4972  }
4973 
4974  // If this Objective-C method does not have a related result type, but we
4975  // are allowed to infer related result types, try to do so based on the
4976  // method family.
4977  ObjCInterfaceDecl *CurrentClass = dyn_cast<ObjCInterfaceDecl>(ClassDecl);
4978  if (!CurrentClass) {
4979  if (ObjCCategoryDecl *Cat = dyn_cast<ObjCCategoryDecl>(ClassDecl))
4980  CurrentClass = Cat->getClassInterface();
4981  else if (ObjCImplDecl *Impl = dyn_cast<ObjCImplDecl>(ClassDecl))
4982  CurrentClass = Impl->getClassInterface();
4983  else if (ObjCCategoryImplDecl *CatImpl
4984  = dyn_cast<ObjCCategoryImplDecl>(ClassDecl))
4985  CurrentClass = CatImpl->getClassInterface();
4986  }
4987 
4989  = CheckRelatedResultTypeCompatibility(*this, ObjCMethod, CurrentClass);
4990 
4991  CheckObjCMethodOverrides(ObjCMethod, CurrentClass, RTC);
4992 
4993  bool ARCError = false;
4994  if (getLangOpts().ObjCAutoRefCount)
4995  ARCError = CheckARCMethodDecl(ObjCMethod);
4996 
4997  // Infer the related result type when possible.
4998  if (!ARCError && RTC == Sema::RTC_Compatible &&
4999  !ObjCMethod->hasRelatedResultType() &&
5000  LangOpts.ObjCInferRelatedResultType) {
5001  bool InferRelatedResultType = false;
5002  switch (ObjCMethod->getMethodFamily()) {
5003  case OMF_None:
5004  case OMF_copy:
5005  case OMF_dealloc:
5006  case OMF_finalize:
5007  case OMF_mutableCopy:
5008  case OMF_release:
5009  case OMF_retainCount:
5010  case OMF_initialize:
5011  case OMF_performSelector:
5012  break;
5013 
5014  case OMF_alloc:
5015  case OMF_new:
5016  InferRelatedResultType = ObjCMethod->isClassMethod();
5017  break;
5018 
5019  case OMF_init:
5020  case OMF_autorelease:
5021  case OMF_retain:
5022  case OMF_self:
5023  InferRelatedResultType = ObjCMethod->isInstanceMethod();
5024  break;
5025  }
5026 
5027  if (InferRelatedResultType &&
5028  !ObjCMethod->getReturnType()->isObjCIndependentClassType())
5029  ObjCMethod->setRelatedResultType();
5030  }
5031 
5032  if (MethodDefinition &&
5033  Context.getTargetInfo().getTriple().getArch() == llvm::Triple::x86)
5034  checkObjCMethodX86VectorTypes(*this, ObjCMethod);
5035 
5036  // + load method cannot have availability attributes. It get called on
5037  // startup, so it has to have the availability of the deployment target.
5038  if (const auto *attr = ObjCMethod->getAttr<AvailabilityAttr>()) {
5039  if (ObjCMethod->isClassMethod() &&
5040  ObjCMethod->getSelector().getAsString() == "load") {
5041  Diag(attr->getLocation(), diag::warn_availability_on_static_initializer)
5042  << 0;
5043  ObjCMethod->dropAttr<AvailabilityAttr>();
5044  }
5045  }
5046 
5047  // Insert the invisible arguments, self and _cmd!
5048  ObjCMethod->createImplicitParams(Context, ObjCMethod->getClassInterface());
5049 
5050  ActOnDocumentableDecl(ObjCMethod);
5051 
5052  return ObjCMethod;
5053 }
5054 
5056  // Following is also an error. But it is caused by a missing @end
5057  // and diagnostic is issued elsewhere.
5058  if (isa<ObjCContainerDecl>(CurContext->getRedeclContext()))
5059  return false;
5060 
5061  // If we switched context to translation unit while we are still lexically in
5062  // an objc container, it means the parser missed emitting an error.
5063  if (isa<TranslationUnitDecl>(getCurLexicalContext()->getRedeclContext()))
5064  return false;
5065 
5066  Diag(D->getLocation(), diag::err_objc_decls_may_only_appear_in_global_scope);
5067  D->setInvalidDecl();
5068 
5069  return true;
5070 }
5071 
5072 /// Called whenever \@defs(ClassName) is encountered in the source. Inserts the
5073 /// instance variables of ClassName into Decls.
5074 void Sema::ActOnDefs(Scope *S, Decl *TagD, SourceLocation DeclStart,
5075  IdentifierInfo *ClassName,
5076  SmallVectorImpl<Decl*> &Decls) {
5077  // Check that ClassName is a valid class
5078  ObjCInterfaceDecl *Class = getObjCInterfaceDecl(ClassName, DeclStart);
5079  if (!Class) {
5080  Diag(DeclStart, diag::err_undef_interface) << ClassName;
5081  return;
5082  }
5084  Diag(DeclStart, diag::err_atdef_nonfragile_interface);
5085  return;
5086  }
5087 
5088  // Collect the instance variables
5090  Context.DeepCollectObjCIvars(Class, true, Ivars);
5091  // For each ivar, create a fresh ObjCAtDefsFieldDecl.
5092  for (unsigned i = 0; i < Ivars.size(); i++) {
5093  const FieldDecl* ID = Ivars[i];
5094  RecordDecl *Record = dyn_cast<RecordDecl>(TagD);
5096  /*FIXME: StartL=*/ID->getLocation(),
5097  ID->getLocation(),
5098  ID->getIdentifier(), ID->getType(),
5099  ID->getBitWidth());
5100  Decls.push_back(FD);
5101  }
5102 
5103  // Introduce all of these fields into the appropriate scope.
5104  for (SmallVectorImpl<Decl*>::iterator D = Decls.begin();
5105  D != Decls.end(); ++D) {
5106  FieldDecl *FD = cast<FieldDecl>(*D);
5107  if (getLangOpts().CPlusPlus)
5108  PushOnScopeChains(FD, S);
5109  else if (RecordDecl *Record = dyn_cast<RecordDecl>(TagD))
5110  Record->addDecl(FD);
5111  }
5112 }
5113 
5114 /// Build a type-check a new Objective-C exception variable declaration.
5116  SourceLocation StartLoc,
5117  SourceLocation IdLoc,
5118  IdentifierInfo *Id,
5119  bool Invalid) {
5120  // ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage
5121  // duration shall not be qualified by an address-space qualifier."
5122  // Since all parameters have automatic store duration, they can not have
5123  // an address space.
5124  if (T.getAddressSpace() != LangAS::Default) {
5125  Diag(IdLoc, diag::err_arg_with_address_space);
5126  Invalid = true;
5127  }
5128 
5129  // An @catch parameter must be an unqualified object pointer type;
5130  // FIXME: Recover from "NSObject foo" by inserting the * in "NSObject *foo"?
5131  if (Invalid) {
5132  // Don't do any further checking.
5133  } else if (T->isDependentType()) {
5134  // Okay: we don't know what this type will instantiate to.
5135  } else if (T->isObjCQualifiedIdType()) {
5136  Invalid = true;
5137  Diag(IdLoc, diag::err_illegal_qualifiers_on_catch_parm);
5138  } else if (T->isObjCIdType()) {
5139  // Okay: we don't know what this type will instantiate to.
5140  } else if (!T->isObjCObjectPointerType()) {
5141  Invalid = true;
5142  Diag(IdLoc, diag::err_catch_param_not_objc_type);
5143  } else if (!T->castAs<ObjCObjectPointerType>()->getInterfaceType()) {
5144  Invalid = true;
5145  Diag(IdLoc, diag::err_catch_param_not_objc_type);
5146  }
5147 
5148  VarDecl *New = VarDecl::Create(Context, CurContext, StartLoc, IdLoc, Id,
5149  T, TInfo, SC_None);
5150  New->setExceptionVariable(true);
5151 
5152  // In ARC, infer 'retaining' for variables of retainable type.
5153  if (getLangOpts().ObjCAutoRefCount && inferObjCARCLifetime(New))
5154  Invalid = true;
5155 
5156  if (Invalid)
5157  New->setInvalidDecl();
5158  return New;
5159 }
5160 
5162  const DeclSpec &DS = D.getDeclSpec();
5163 
5164  // We allow the "register" storage class on exception variables because
5165  // GCC did, but we drop it completely. Any other storage class is an error.
5167  Diag(DS.getStorageClassSpecLoc(), diag::warn_register_objc_catch_parm)
5169  } else if (DeclSpec::SCS SCS = DS.getStorageClassSpec()) {
5170  Diag(DS.getStorageClassSpecLoc(), diag::err_storage_spec_on_catch_parm)
5172  }
5173  if (DS.isInlineSpecified())
5174  Diag(DS.getInlineSpecLoc(), diag::err_inline_non_function)
5175  << getLangOpts().CPlusPlus17;
5178  diag::err_invalid_thread)
5179  << DeclSpec::getSpecifierName(TSCS);
5181 
5183 
5184  // Check that there are no default arguments inside the type of this
5185  // exception object (C++ only).
5186  if (getLangOpts().CPlusPlus)
5188 
5189  TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S);
5190  QualType ExceptionType = TInfo->getType();
5191 
5192  VarDecl *New = BuildObjCExceptionDecl(TInfo, ExceptionType,
5193  D.getSourceRange().getBegin(),
5194  D.getIdentifierLoc(),
5195  D.getIdentifier(),
5196  D.isInvalidType());
5197 
5198  // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1).
5199  if (D.getCXXScopeSpec().isSet()) {
5200  Diag(D.getIdentifierLoc(), diag::err_qualified_objc_catch_parm)
5201  << D.getCXXScopeSpec().getRange();
5202  New->setInvalidDecl();
5203  }
5204 
5205  // Add the parameter declaration into this scope.
5206  S->AddDecl(New);
5207  if (D.getIdentifier())
5208  IdResolver.AddDecl(New);
5209 
5210  ProcessDeclAttributes(S, New, D);
5211 
5212  if (New->hasAttr<BlocksAttr>())
5213  Diag(New->getLocation(), diag::err_block_on_nonlocal);
5214  return New;
5215 }
5216 
5217 /// CollectIvarsToConstructOrDestruct - Collect those ivars which require
5218 /// initialization.
5221  for (ObjCIvarDecl *Iv = OI->all_declared_ivar_begin(); Iv;
5222  Iv= Iv->getNextIvar()) {
5223  QualType QT = Context.getBaseElementType(Iv->getType());
5224  if (QT->isRecordType())
5225  Ivars.push_back(Iv);
5226  }
5227 }
5228 
5230  // Load referenced selectors from the external source.
5231  if (ExternalSource) {
5233  ExternalSource->ReadReferencedSelectors(Sels);
5234  for (unsigned I = 0, N = Sels.size(); I != N; ++I)
5235  ReferencedSelectors[Sels[I].first] = Sels[I].second;
5236  }
5237 
5238  // Warning will be issued only when selector table is
5239  // generated (which means there is at lease one implementation
5240  // in the TU). This is to match gcc's behavior.
5241  if (ReferencedSelectors.empty() ||
5243  return;
5244  for (auto &SelectorAndLocation : ReferencedSelectors) {
5245  Selector Sel = SelectorAndLocation.first;
5246  SourceLocation Loc = SelectorAndLocation.second;
5248  Diag(Loc, diag::warn_unimplemented_selector) << Sel;
5249  }
5250 }
5251 
5252 ObjCIvarDecl *
5254  const ObjCPropertyDecl *&PDecl) const {
5255  if (Method->isClassMethod())
5256  return nullptr;
5257  const ObjCInterfaceDecl *IDecl = Method->getClassInterface();
5258  if (!IDecl)
5259  return nullptr;
5260  Method = IDecl->lookupMethod(Method->getSelector(), /*isInstance=*/true,
5261  /*shallowCategoryLookup=*/false,
5262  /*followSuper=*/false);
5263  if (!Method || !Method->isPropertyAccessor())
5264  return nullptr;
5265  if ((PDecl = Method->findPropertyDecl()))
5266  if (ObjCIvarDecl *IV = PDecl->getPropertyIvarDecl()) {
5267  // property backing ivar must belong to property's class
5268  // or be a private ivar in class's implementation.
5269  // FIXME. fix the const-ness issue.
5270  IV = const_cast<ObjCInterfaceDecl *>(IDecl)->lookupInstanceVariable(
5271  IV->getIdentifier());
5272  return IV;
5273  }
5274  return nullptr;
5275 }
5276 
5277 namespace {
5278  /// Used by Sema::DiagnoseUnusedBackingIvarInAccessor to check if a property
5279  /// accessor references the backing ivar.
5280  class UnusedBackingIvarChecker :
5281  public RecursiveASTVisitor<UnusedBackingIvarChecker> {
5282  public:
5283  Sema &S;
5284  const ObjCMethodDecl *Method;
5285  const ObjCIvarDecl *IvarD;
5286  bool AccessedIvar;
5287  bool InvokedSelfMethod;
5288 
5289  UnusedBackingIvarChecker(Sema &S, const ObjCMethodDecl *Method,
5290  const ObjCIvarDecl *IvarD)
5291  : S(S), Method(Method), IvarD(IvarD),
5292  AccessedIvar(false), InvokedSelfMethod(false) {
5293  assert(IvarD);
5294  }
5295 
5296  bool VisitObjCIvarRefExpr(ObjCIvarRefExpr *E) {
5297  if (E->getDecl() == IvarD) {
5298  AccessedIvar = true;
5299  return false;
5300  }
5301  return true;
5302  }
5303 
5304  bool VisitObjCMessageExpr(ObjCMessageExpr *E) {
5306  S.isSelfExpr(E->getInstanceReceiver(), Method)) {
5307  InvokedSelfMethod = true;
5308  }
5309  return true;
5310  }
5311  };
5312 } // end anonymous namespace
5313 
5315  const ObjCImplementationDecl *ImplD) {
5316  if (S->hasUnrecoverableErrorOccurred())
5317  return;
5318 
5319  for (const auto *CurMethod : ImplD->instance_methods()) {
5320  unsigned DIAG = diag::warn_unused_property_backing_ivar;
5321  SourceLocation Loc = CurMethod->getLocation();
5322  if (Diags.isIgnored(DIAG, Loc))
5323  continue;
5324 
5325  const ObjCPropertyDecl *PDecl;
5326  const ObjCIvarDecl *IV = GetIvarBackingPropertyAccessor(CurMethod, PDecl);
5327  if (!IV)
5328  continue;
5329 
5330  if (CurMethod->isSynthesizedAccessorStub())
5331  continue;
5332 
5333  UnusedBackingIvarChecker Checker(*this, CurMethod, IV);
5334  Checker.TraverseStmt(CurMethod->getBody());
5335  if (Checker.AccessedIvar)
5336  continue;
5337 
5338  // Do not issue this warning if backing ivar is used somewhere and accessor
5339  // implementation makes a self call. This is to prevent false positive in
5340  // cases where the ivar is accessed by another method that the accessor
5341  // delegates to.
5342  if (!IV->isReferenced() || !Checker.InvokedSelfMethod) {
5343  Diag(Loc, DIAG) << IV;
5344  Diag(PDecl->getLocation(), diag::note_property_declare);
5345  }
5346  }
5347 }
void FindProtocolDeclaration(bool WarnOnDeclarations, bool ForObjCContainer, ArrayRef< IdentifierLocPair > ProtocolId, SmallVectorImpl< Decl * > &Protocols)
FindProtocolDeclaration - This routine looks up protocols and issues an error if they are not declare...
void setMethodParams(ASTContext &C, ArrayRef< ParmVarDecl * > Params, ArrayRef< SourceLocation > SelLocs=llvm::None)
Sets the method's parameters and selector source locations.
Definition: DeclObjC.cpp:892
const ObjCInterfaceType * getInterfaceType() const
If this pointer points to an Objective C @interface type, gets the type for that interface.
Definition: Type.cpp:1670
const internal::VariadicAllOfMatcher< Type > type
Matches Types in the clang AST.
Defines the clang::ASTContext interface.
bool hasDefinition() const
Determine whether this class has been defined.
Definition: DeclObjC.h:1513
static bool tryMatchRecordTypes(ASTContext &Context, Sema::MethodMatchStrategy strategy, const Type *left, const Type *right)
ObjCIvarDecl * GetIvarBackingPropertyAccessor(const ObjCMethodDecl *Method, const ObjCPropertyDecl *&PDecl) const
GetIvarBackingPropertyAccessor - If method is a property setter/getter and it property has a backing ...
void DiagnoseClassExtensionDupMethods(ObjCCategoryDecl *CAT, ObjCInterfaceDecl *ID)
DiagnoseClassExtensionDupMethods - Check for duplicate declaration of a class method in its extension...
bool isClassMethod() const
Definition: DeclObjC.h:439
Decl * ActOnStartCategoryInterface(SourceLocation AtInterfaceLoc, IdentifierInfo *ClassName, SourceLocation ClassLoc, ObjCTypeParamList *typeParamList, IdentifierInfo *CategoryName, SourceLocation CategoryLoc, Decl *const *ProtoRefs, unsigned NumProtoRefs, const SourceLocation *ProtoLocs, SourceLocation EndProtoLoc, const ParsedAttributesView &AttrList)
void setImplicit(bool I=true)
Definition: DeclBase.h:564
ParsedType CreateParsedType(QualType T, TypeSourceInfo *TInfo)
Package the given type and TSI into a ParsedType.
Definition: SemaType.cpp:6284
bool isSelfExpr(Expr *RExpr)
Private Helper predicate to check for 'self'.
The receiver is an object instance.
Definition: ExprObjC.h:1091
void setEndOfDefinitionLoc(SourceLocation LE)
Definition: DeclObjC.h:1863
VersionTuple getPlatformMinVersion() const
Retrieve the minimum desired version of the platform, to which the program should be compiled.
Definition: TargetInfo.h:1376
ExternalSemaSource * getExternalSource() const
Definition: Sema.h:1528
bool isObjCQualifiedIdType() const
True if this is equivalent to 'id.
Definition: Type.h:6133
Smart pointer class that efficiently represents Objective-C method names.
QualType getObjCIdType() const
Represents the Objective-CC id type.
Definition: ASTContext.h:1870
QualType getAdjustedParameterType(QualType T) const
Perform adjustment on the parameter type of a function.
void PushExpressionEvaluationContext(ExpressionEvaluationContext NewContext, Decl *LambdaContextDecl=nullptr, ExpressionEvaluationContextRecord::ExpressionKind Type=ExpressionEvaluationContextRecord::EK_Other)
Definition: SemaExpr.cpp:16254
PointerType - C99 6.7.5.1 - Pointer Declarators.
Definition: Type.h:2624
A (possibly-)qualified type.
Definition: Type.h:661
ASTConsumer & Consumer
Definition: Sema.h:400
Simple class containing the result of Sema::CorrectTypo.
void setStarLoc(SourceLocation Loc)
Definition: TypeLoc.h:1302
unsigned param_size() const
Definition: DeclObjC.h:350
TypeResult actOnObjCTypeArgsAndProtocolQualifiers(Scope *S, SourceLocation Loc, ParsedType BaseType, SourceLocation TypeArgsLAngleLoc, ArrayRef< ParsedType > TypeArgs, SourceLocation TypeArgsRAngleLoc, SourceLocation ProtocolLAngleLoc, ArrayRef< Decl * > Protocols, ArrayRef< SourceLocation > ProtocolLocs, SourceLocation ProtocolRAngleLoc)
Build a specialized and/or protocol-qualified Objective-C type.
Definition: SemaType.cpp:1141
ObjCInterfaceDecl * getClassInterface()
Definition: DeclObjC.h:2311
all_protocol_range all_referenced_protocols() const
Definition: DeclObjC.h:1402
ObjCInterfaceDecl * getClassInterface()
Definition: DeclObjC.cpp:1159
void startDefinition()
Starts the definition of this Objective-C class, taking it from a forward declaration (@class) to a d...
Definition: DeclObjC.cpp:612
ObjCDeclQualifier getObjCDeclQualifier() const
Definition: DeclSpec.h:846
static QualType getObjectType(APValue::LValueBase B)
Retrieves the "underlying object type" of the given expression, as used by __builtin_object_size.
iterator begin() const
Definition: DeclObjC.h:91
llvm::DenseSet< IdentifierInfo * > ProtocolNameSet
FIXME: Type hierarchies in Objective-C can be deep.
Ordinary name lookup, which finds ordinary names (functions, variables, typedefs, etc....
Definition: Sema.h:3897
bool CheckParmsForFunctionDef(ArrayRef< ParmVarDecl * > Parameters, bool CheckParameterNames)
Helpers for dealing with blocks and functions.
bool LookupName(LookupResult &R, Scope *S, bool AllowBuiltinCreation=false)
Perform unqualified name lookup starting from a given scope.
Look up the name of an Objective-C protocol.
Definition: Sema.h:3934