1 //===--- SemaDeclObjC.cpp - Semantic Analysis for ObjC Declarations -------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file implements semantic analysis for Objective C declarations.
12 //===----------------------------------------------------------------------===//
14 #include "TypeLocBuilder.h"
15 #include "clang/AST/ASTConsumer.h"
16 #include "clang/AST/ASTContext.h"
17 #include "clang/AST/ASTMutationListener.h"
18 #include "clang/AST/DeclObjC.h"
19 #include "clang/AST/Expr.h"
20 #include "clang/AST/ExprObjC.h"
21 #include "clang/AST/RecursiveASTVisitor.h"
22 #include "clang/Basic/SourceManager.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"
27 #include "clang/Sema/SemaInternal.h"
28 #include "llvm/ADT/DenseMap.h"
29 #include "llvm/ADT/DenseSet.h"
31 using namespace clang;
33 /// Check whether the given method, which must be in the 'init'
34 /// family, is a valid member of that family.
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
40 /// \return true to indicate that there was an error and appropriate
41 /// actions were taken
42 bool Sema::checkInitMethod(ObjCMethodDecl *method,
43 QualType receiverTypeIfCall) {
44 if (method->isInvalidDecl()) return true;
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).
50 // We ignore protocols here. Should we? What about Class?
52 const ObjCObjectType *result =
53 method->getReturnType()->castAs<ObjCObjectPointerType>()->getObjectType();
55 if (result->isObjCId()) {
57 } else if (result->isObjCClass()) {
58 // fall through: always an error
60 ObjCInterfaceDecl *resultClass = result->getInterface();
61 assert(resultClass && "unexpected object type!");
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()))
70 // Otherwise, we try to compare class types.
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())
79 receiverClass = receiverTypeIfCall->castAs<ObjCObjectPointerType>()
82 // This can be null for calls to e.g. id<Foo>.
83 if (!receiverClass) return false;
85 receiverClass = method->getClassInterface();
86 assert(receiverClass && "method not associated with a class!");
89 // If either class is a subclass of the other, it's fine.
90 if (receiverClass->isSuperClassOf(resultClass) ||
91 resultClass->isSuperClassOf(receiverClass))
96 SourceLocation loc = method->getLocation();
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));
106 // Otherwise, it's an error.
107 Diag(loc, diag::err_arc_init_method_unrelated_result_type);
108 method->setInvalidDecl();
112 void Sema::CheckObjCMethodOverride(ObjCMethodDecl *NewMethod,
113 const ObjCMethodDecl *Overridden) {
114 if (Overridden->hasRelatedResultType() &&
115 !NewMethod->hasRelatedResultType()) {
116 // This can only happen when the method follows a naming convention that
117 // implies a related result type, and the original (overridden) method has
118 // a suitable return type, but the new (overriding) method does not have
119 // a suitable return type.
120 QualType ResultType = NewMethod->getReturnType();
121 SourceRange ResultTypeRange = NewMethod->getReturnTypeSourceRange();
123 // Figure out which class this method is part of, if any.
124 ObjCInterfaceDecl *CurrentClass
125 = dyn_cast<ObjCInterfaceDecl>(NewMethod->getDeclContext());
127 DeclContext *DC = NewMethod->getDeclContext();
128 if (ObjCCategoryDecl *Cat = dyn_cast<ObjCCategoryDecl>(DC))
129 CurrentClass = Cat->getClassInterface();
130 else if (ObjCImplDecl *Impl = dyn_cast<ObjCImplDecl>(DC))
131 CurrentClass = Impl->getClassInterface();
132 else if (ObjCCategoryImplDecl *CatImpl
133 = dyn_cast<ObjCCategoryImplDecl>(DC))
134 CurrentClass = CatImpl->getClassInterface();
138 Diag(NewMethod->getLocation(),
139 diag::warn_related_result_type_compatibility_class)
140 << Context.getObjCInterfaceType(CurrentClass)
144 Diag(NewMethod->getLocation(),
145 diag::warn_related_result_type_compatibility_protocol)
150 if (ObjCMethodFamily Family = Overridden->getMethodFamily())
151 Diag(Overridden->getLocation(),
152 diag::note_related_result_type_family)
153 << /*overridden method*/ 0
156 Diag(Overridden->getLocation(),
157 diag::note_related_result_type_overridden);
159 if (getLangOpts().ObjCAutoRefCount) {
160 if ((NewMethod->hasAttr<NSReturnsRetainedAttr>() !=
161 Overridden->hasAttr<NSReturnsRetainedAttr>())) {
162 Diag(NewMethod->getLocation(),
163 diag::err_nsreturns_retained_attribute_mismatch) << 1;
164 Diag(Overridden->getLocation(), diag::note_previous_decl)
167 if ((NewMethod->hasAttr<NSReturnsNotRetainedAttr>() !=
168 Overridden->hasAttr<NSReturnsNotRetainedAttr>())) {
169 Diag(NewMethod->getLocation(),
170 diag::err_nsreturns_retained_attribute_mismatch) << 0;
171 Diag(Overridden->getLocation(), diag::note_previous_decl)
174 ObjCMethodDecl::param_const_iterator oi = Overridden->param_begin(),
175 oe = Overridden->param_end();
176 for (ObjCMethodDecl::param_iterator
177 ni = NewMethod->param_begin(), ne = NewMethod->param_end();
178 ni != ne && oi != oe; ++ni, ++oi) {
179 const ParmVarDecl *oldDecl = (*oi);
180 ParmVarDecl *newDecl = (*ni);
181 if (newDecl->hasAttr<NSConsumedAttr>() !=
182 oldDecl->hasAttr<NSConsumedAttr>()) {
183 Diag(newDecl->getLocation(),
184 diag::err_nsconsumed_attribute_mismatch);
185 Diag(oldDecl->getLocation(), diag::note_previous_decl)
192 /// \brief Check a method declaration for compatibility with the Objective-C
194 bool Sema::CheckARCMethodDecl(ObjCMethodDecl *method) {
195 ObjCMethodFamily family = method->getMethodFamily();
201 case OMF_autorelease:
202 case OMF_retainCount:
205 case OMF_performSelector:
209 if (!Context.hasSameType(method->getReturnType(), Context.VoidTy)) {
210 SourceRange ResultTypeRange = method->getReturnTypeSourceRange();
211 if (ResultTypeRange.isInvalid())
212 Diag(method->getLocation(), diag::err_dealloc_bad_result_type)
213 << method->getReturnType()
214 << FixItHint::CreateInsertion(method->getSelectorLoc(0), "(void)");
216 Diag(method->getLocation(), diag::err_dealloc_bad_result_type)
217 << method->getReturnType()
218 << FixItHint::CreateReplacement(ResultTypeRange, "void");
224 // If the method doesn't obey the init rules, don't bother annotating it.
225 if (checkInitMethod(method, QualType()))
228 method->addAttr(NSConsumesSelfAttr::CreateImplicit(Context));
230 // Don't add a second copy of this attribute, but otherwise don't
231 // let it be suppressed.
232 if (method->hasAttr<NSReturnsRetainedAttr>())
238 case OMF_mutableCopy:
240 if (method->hasAttr<NSReturnsRetainedAttr>() ||
241 method->hasAttr<NSReturnsNotRetainedAttr>() ||
242 method->hasAttr<NSReturnsAutoreleasedAttr>())
247 method->addAttr(NSReturnsRetainedAttr::CreateImplicit(Context));
251 static void DiagnoseObjCImplementedDeprecations(Sema &S, const NamedDecl *ND,
252 SourceLocation ImplLoc) {
255 bool IsCategory = false;
256 AvailabilityResult Availability = ND->getAvailability();
257 if (Availability != AR_Deprecated) {
258 if (isa<ObjCMethodDecl>(ND)) {
259 if (Availability != AR_Unavailable)
261 // Warn about implementing unavailable methods.
262 S.Diag(ImplLoc, diag::warn_unavailable_def);
263 S.Diag(ND->getLocation(), diag::note_method_declared_at)
264 << ND->getDeclName();
267 if (const auto *CD = dyn_cast<ObjCCategoryDecl>(ND)) {
268 if (!CD->getClassInterface()->isDeprecated())
270 ND = CD->getClassInterface();
275 S.Diag(ImplLoc, diag::warn_deprecated_def)
276 << (isa<ObjCMethodDecl>(ND)
278 : isa<ObjCCategoryDecl>(ND) || IsCategory ? /*Category*/ 2
280 if (isa<ObjCMethodDecl>(ND))
281 S.Diag(ND->getLocation(), diag::note_method_declared_at)
282 << ND->getDeclName();
284 S.Diag(ND->getLocation(), diag::note_previous_decl)
285 << (isa<ObjCCategoryDecl>(ND) ? "category" : "class");
288 /// AddAnyMethodToGlobalPool - Add any method, instance or factory to global
290 void Sema::AddAnyMethodToGlobalPool(Decl *D) {
291 ObjCMethodDecl *MDecl = dyn_cast_or_null<ObjCMethodDecl>(D);
293 // If we don't have a valid method decl, simply return.
296 if (MDecl->isInstanceMethod())
297 AddInstanceMethodToGlobalPool(MDecl, true);
299 AddFactoryMethodToGlobalPool(MDecl, true);
302 /// HasExplicitOwnershipAttr - returns true when pointer to ObjC pointer
303 /// has explicit ownership attribute; false otherwise.
305 HasExplicitOwnershipAttr(Sema &S, ParmVarDecl *Param) {
306 QualType T = Param->getType();
308 if (const PointerType *PT = T->getAs<PointerType>()) {
309 T = PT->getPointeeType();
310 } else if (const ReferenceType *RT = T->getAs<ReferenceType>()) {
311 T = RT->getPointeeType();
316 // If we have a lifetime qualifier, but it's local, we must have
317 // inferred it. So, it is implicit.
318 return !T.getLocalQualifiers().hasObjCLifetime();
321 /// ActOnStartOfObjCMethodDef - This routine sets up parameters; invisible
322 /// and user declared, in the method definition's AST.
323 void Sema::ActOnStartOfObjCMethodDef(Scope *FnBodyScope, Decl *D) {
324 assert((getCurMethodDecl() == nullptr) && "Methodparsing confused");
325 ObjCMethodDecl *MDecl = dyn_cast_or_null<ObjCMethodDecl>(D);
327 // If we don't have a valid method decl, simply return.
331 // Allow all of Sema to see that we are entering a method definition.
332 PushDeclContext(FnBodyScope, MDecl);
335 // Create Decl objects for each parameter, entrring them in the scope for
336 // binding to their use.
338 // Insert the invisible arguments, self and _cmd!
339 MDecl->createImplicitParams(Context, MDecl->getClassInterface());
341 PushOnScopeChains(MDecl->getSelfDecl(), FnBodyScope);
342 PushOnScopeChains(MDecl->getCmdDecl(), FnBodyScope);
344 // The ObjC parser requires parameter names so there's no need to check.
345 CheckParmsForFunctionDef(MDecl->parameters(),
346 /*CheckParameterNames=*/false);
348 // Introduce all of the other parameters into this scope.
349 for (auto *Param : MDecl->parameters()) {
350 if (!Param->isInvalidDecl() &&
351 getLangOpts().ObjCAutoRefCount &&
352 !HasExplicitOwnershipAttr(*this, Param))
353 Diag(Param->getLocation(), diag::warn_arc_strong_pointer_objc_pointer) <<
356 if (Param->getIdentifier())
357 PushOnScopeChains(Param, FnBodyScope);
360 // In ARC, disallow definition of retain/release/autorelease/retainCount
361 if (getLangOpts().ObjCAutoRefCount) {
362 switch (MDecl->getMethodFamily()) {
364 case OMF_retainCount:
366 case OMF_autorelease:
367 Diag(MDecl->getLocation(), diag::err_arc_illegal_method_def)
368 << 0 << MDecl->getSelector();
376 case OMF_mutableCopy:
381 case OMF_performSelector:
386 // Warn on deprecated methods under -Wdeprecated-implementations,
387 // and prepare for warning on missing super calls.
388 if (ObjCInterfaceDecl *IC = MDecl->getClassInterface()) {
389 ObjCMethodDecl *IMD =
390 IC->lookupMethod(MDecl->getSelector(), MDecl->isInstanceMethod());
393 ObjCImplDecl *ImplDeclOfMethodDef =
394 dyn_cast<ObjCImplDecl>(MDecl->getDeclContext());
395 ObjCContainerDecl *ContDeclOfMethodDecl =
396 dyn_cast<ObjCContainerDecl>(IMD->getDeclContext());
397 ObjCImplDecl *ImplDeclOfMethodDecl = nullptr;
398 if (ObjCInterfaceDecl *OID = dyn_cast<ObjCInterfaceDecl>(ContDeclOfMethodDecl))
399 ImplDeclOfMethodDecl = OID->getImplementation();
400 else if (ObjCCategoryDecl *CD = dyn_cast<ObjCCategoryDecl>(ContDeclOfMethodDecl)) {
401 if (CD->IsClassExtension()) {
402 if (ObjCInterfaceDecl *OID = CD->getClassInterface())
403 ImplDeclOfMethodDecl = OID->getImplementation();
405 ImplDeclOfMethodDecl = CD->getImplementation();
407 // No need to issue deprecated warning if deprecated mehod in class/category
408 // is being implemented in its own implementation (no overriding is involved).
409 if (!ImplDeclOfMethodDecl || ImplDeclOfMethodDecl != ImplDeclOfMethodDef)
410 DiagnoseObjCImplementedDeprecations(*this, IMD, MDecl->getLocation());
413 if (MDecl->getMethodFamily() == OMF_init) {
414 if (MDecl->isDesignatedInitializerForTheInterface()) {
415 getCurFunction()->ObjCIsDesignatedInit = true;
416 getCurFunction()->ObjCWarnForNoDesignatedInitChain =
417 IC->getSuperClass() != nullptr;
418 } else if (IC->hasDesignatedInitializers()) {
419 getCurFunction()->ObjCIsSecondaryInit = true;
420 getCurFunction()->ObjCWarnForNoInitDelegation = true;
424 // If this is "dealloc" or "finalize", set some bit here.
425 // Then in ActOnSuperMessage() (SemaExprObjC), set it back to false.
426 // Finally, in ActOnFinishFunctionBody() (SemaDecl), warn if flag is set.
427 // Only do this if the current class actually has a superclass.
428 if (const ObjCInterfaceDecl *SuperClass = IC->getSuperClass()) {
429 ObjCMethodFamily Family = MDecl->getMethodFamily();
430 if (Family == OMF_dealloc) {
431 if (!(getLangOpts().ObjCAutoRefCount ||
432 getLangOpts().getGC() == LangOptions::GCOnly))
433 getCurFunction()->ObjCShouldCallSuper = true;
435 } else if (Family == OMF_finalize) {
436 if (Context.getLangOpts().getGC() != LangOptions::NonGC)
437 getCurFunction()->ObjCShouldCallSuper = true;
440 const ObjCMethodDecl *SuperMethod =
441 SuperClass->lookupMethod(MDecl->getSelector(),
442 MDecl->isInstanceMethod());
443 getCurFunction()->ObjCShouldCallSuper =
444 (SuperMethod && SuperMethod->hasAttr<ObjCRequiresSuperAttr>());
452 // Callback to only accept typo corrections that are Objective-C classes.
453 // If an ObjCInterfaceDecl* is given to the constructor, then the validation
454 // function will reject corrections to that class.
455 class ObjCInterfaceValidatorCCC : public CorrectionCandidateCallback {
457 ObjCInterfaceValidatorCCC() : CurrentIDecl(nullptr) {}
458 explicit ObjCInterfaceValidatorCCC(ObjCInterfaceDecl *IDecl)
459 : CurrentIDecl(IDecl) {}
461 bool ValidateCandidate(const TypoCorrection &candidate) override {
462 ObjCInterfaceDecl *ID = candidate.getCorrectionDeclAs<ObjCInterfaceDecl>();
463 return ID && !declaresSameEntity(ID, CurrentIDecl);
467 ObjCInterfaceDecl *CurrentIDecl;
470 } // end anonymous namespace
472 static void diagnoseUseOfProtocols(Sema &TheSema,
473 ObjCContainerDecl *CD,
474 ObjCProtocolDecl *const *ProtoRefs,
475 unsigned NumProtoRefs,
476 const SourceLocation *ProtoLocs) {
478 // Diagnose availability in the context of the ObjC container.
479 Sema::ContextRAII SavedContext(TheSema, CD);
480 for (unsigned i = 0; i < NumProtoRefs; ++i) {
481 (void)TheSema.DiagnoseUseOfDecl(ProtoRefs[i], ProtoLocs[i],
482 /*UnknownObjCClass=*/nullptr,
483 /*ObjCPropertyAccess=*/false,
484 /*AvoidPartialAvailabilityChecks=*/true);
489 ActOnSuperClassOfClassInterface(Scope *S,
490 SourceLocation AtInterfaceLoc,
491 ObjCInterfaceDecl *IDecl,
492 IdentifierInfo *ClassName,
493 SourceLocation ClassLoc,
494 IdentifierInfo *SuperName,
495 SourceLocation SuperLoc,
496 ArrayRef<ParsedType> SuperTypeArgs,
497 SourceRange SuperTypeArgsRange) {
498 // Check if a different kind of symbol declared in this scope.
499 NamedDecl *PrevDecl = LookupSingleName(TUScope, SuperName, SuperLoc,
503 // Try to correct for a typo in the superclass name without correcting
504 // to the class we're defining.
505 if (TypoCorrection Corrected = CorrectTypo(
506 DeclarationNameInfo(SuperName, SuperLoc),
507 LookupOrdinaryName, TUScope,
508 nullptr, llvm::make_unique<ObjCInterfaceValidatorCCC>(IDecl),
509 CTK_ErrorRecovery)) {
510 diagnoseTypo(Corrected, PDiag(diag::err_undef_superclass_suggest)
511 << SuperName << ClassName);
512 PrevDecl = Corrected.getCorrectionDeclAs<ObjCInterfaceDecl>();
516 if (declaresSameEntity(PrevDecl, IDecl)) {
517 Diag(SuperLoc, diag::err_recursive_superclass)
518 << SuperName << ClassName << SourceRange(AtInterfaceLoc, ClassLoc);
519 IDecl->setEndOfDefinitionLoc(ClassLoc);
521 ObjCInterfaceDecl *SuperClassDecl =
522 dyn_cast_or_null<ObjCInterfaceDecl>(PrevDecl);
523 QualType SuperClassType;
525 // Diagnose classes that inherit from deprecated classes.
526 if (SuperClassDecl) {
527 (void)DiagnoseUseOfDecl(SuperClassDecl, SuperLoc);
528 SuperClassType = Context.getObjCInterfaceType(SuperClassDecl);
531 if (PrevDecl && !SuperClassDecl) {
532 // The previous declaration was not a class decl. Check if we have a
533 // typedef. If we do, get the underlying class type.
534 if (const TypedefNameDecl *TDecl =
535 dyn_cast_or_null<TypedefNameDecl>(PrevDecl)) {
536 QualType T = TDecl->getUnderlyingType();
537 if (T->isObjCObjectType()) {
538 if (NamedDecl *IDecl = T->getAs<ObjCObjectType>()->getInterface()) {
539 SuperClassDecl = dyn_cast<ObjCInterfaceDecl>(IDecl);
540 SuperClassType = Context.getTypeDeclType(TDecl);
542 // This handles the following case:
543 // @interface NewI @end
544 // typedef NewI DeprI __attribute__((deprecated("blah")))
545 // @interface SI : DeprI /* warn here */ @end
546 (void)DiagnoseUseOfDecl(const_cast<TypedefNameDecl*>(TDecl), SuperLoc);
551 // This handles the following case:
553 // typedef int SuperClass;
554 // @interface MyClass : SuperClass {} @end
556 if (!SuperClassDecl) {
557 Diag(SuperLoc, diag::err_redefinition_different_kind) << SuperName;
558 Diag(PrevDecl->getLocation(), diag::note_previous_definition);
562 if (!dyn_cast_or_null<TypedefNameDecl>(PrevDecl)) {
564 Diag(SuperLoc, diag::err_undef_superclass)
565 << SuperName << ClassName << SourceRange(AtInterfaceLoc, ClassLoc);
566 else if (RequireCompleteType(SuperLoc,
568 diag::err_forward_superclass,
569 SuperClassDecl->getDeclName(),
571 SourceRange(AtInterfaceLoc, ClassLoc))) {
572 SuperClassDecl = nullptr;
573 SuperClassType = QualType();
577 if (SuperClassType.isNull()) {
578 assert(!SuperClassDecl && "Failed to set SuperClassType?");
582 // Handle type arguments on the superclass.
583 TypeSourceInfo *SuperClassTInfo = nullptr;
584 if (!SuperTypeArgs.empty()) {
585 TypeResult fullSuperClassType = actOnObjCTypeArgsAndProtocolQualifiers(
588 CreateParsedType(SuperClassType,
590 SuperTypeArgsRange.getBegin(),
592 SuperTypeArgsRange.getEnd(),
597 if (!fullSuperClassType.isUsable())
600 SuperClassType = GetTypeFromParser(fullSuperClassType.get(),
604 if (!SuperClassTInfo) {
605 SuperClassTInfo = Context.getTrivialTypeSourceInfo(SuperClassType,
609 IDecl->setSuperClass(SuperClassTInfo);
610 IDecl->setEndOfDefinitionLoc(SuperClassTInfo->getTypeLoc().getLocEnd());
614 DeclResult Sema::actOnObjCTypeParam(Scope *S,
615 ObjCTypeParamVariance variance,
616 SourceLocation varianceLoc,
618 IdentifierInfo *paramName,
619 SourceLocation paramLoc,
620 SourceLocation colonLoc,
621 ParsedType parsedTypeBound) {
622 // If there was an explicitly-provided type bound, check it.
623 TypeSourceInfo *typeBoundInfo = nullptr;
624 if (parsedTypeBound) {
625 // The type bound can be any Objective-C pointer type.
626 QualType typeBound = GetTypeFromParser(parsedTypeBound, &typeBoundInfo);
627 if (typeBound->isObjCObjectPointerType()) {
629 } else if (typeBound->isObjCObjectType()) {
630 // The user forgot the * on an Objective-C pointer type, e.g.,
632 SourceLocation starLoc = getLocForEndOfToken(
633 typeBoundInfo->getTypeLoc().getEndLoc());
634 Diag(typeBoundInfo->getTypeLoc().getBeginLoc(),
635 diag::err_objc_type_param_bound_missing_pointer)
636 << typeBound << paramName
637 << FixItHint::CreateInsertion(starLoc, " *");
639 // Create a new type location builder so we can update the type
640 // location information we have.
641 TypeLocBuilder builder;
642 builder.pushFullCopy(typeBoundInfo->getTypeLoc());
644 // Create the Objective-C pointer type.
645 typeBound = Context.getObjCObjectPointerType(typeBound);
646 ObjCObjectPointerTypeLoc newT
647 = builder.push<ObjCObjectPointerTypeLoc>(typeBound);
648 newT.setStarLoc(starLoc);
650 // Form the new type source information.
651 typeBoundInfo = builder.getTypeSourceInfo(Context, typeBound);
653 // Not a valid type bound.
654 Diag(typeBoundInfo->getTypeLoc().getBeginLoc(),
655 diag::err_objc_type_param_bound_nonobject)
656 << typeBound << paramName;
658 // Forget the bound; we'll default to id later.
659 typeBoundInfo = nullptr;
662 // Type bounds cannot have qualifiers (even indirectly) or explicit
665 QualType typeBound = typeBoundInfo->getType();
666 TypeLoc qual = typeBoundInfo->getTypeLoc().findExplicitQualifierLoc();
667 if (qual || typeBound.hasQualifiers()) {
668 bool diagnosed = false;
669 SourceRange rangeToRemove;
671 if (auto attr = qual.getAs<AttributedTypeLoc>()) {
672 rangeToRemove = attr.getLocalSourceRange();
673 if (attr.getTypePtr()->getImmediateNullability()) {
674 Diag(attr.getLocStart(),
675 diag::err_objc_type_param_bound_explicit_nullability)
676 << paramName << typeBound
677 << FixItHint::CreateRemoval(rangeToRemove);
684 Diag(qual ? qual.getLocStart()
685 : typeBoundInfo->getTypeLoc().getLocStart(),
686 diag::err_objc_type_param_bound_qualified)
687 << paramName << typeBound << typeBound.getQualifiers().getAsString()
688 << FixItHint::CreateRemoval(rangeToRemove);
691 // If the type bound has qualifiers other than CVR, we need to strip
692 // them or we'll probably assert later when trying to apply new
694 Qualifiers quals = typeBound.getQualifiers();
695 quals.removeCVRQualifiers();
696 if (!quals.empty()) {
698 Context.getTrivialTypeSourceInfo(typeBound.getUnqualifiedType());
704 // If there was no explicit type bound (or we removed it due to an error),
706 if (!typeBoundInfo) {
707 colonLoc = SourceLocation();
708 typeBoundInfo = Context.getTrivialTypeSourceInfo(Context.getObjCIdType());
711 // Create the type parameter.
712 return ObjCTypeParamDecl::Create(Context, CurContext, variance, varianceLoc,
713 index, paramLoc, paramName, colonLoc,
717 ObjCTypeParamList *Sema::actOnObjCTypeParamList(Scope *S,
718 SourceLocation lAngleLoc,
719 ArrayRef<Decl *> typeParamsIn,
720 SourceLocation rAngleLoc) {
721 // We know that the array only contains Objective-C type parameters.
722 ArrayRef<ObjCTypeParamDecl *>
724 reinterpret_cast<ObjCTypeParamDecl * const *>(typeParamsIn.data()),
725 typeParamsIn.size());
727 // Diagnose redeclarations of type parameters.
728 // We do this now because Objective-C type parameters aren't pushed into
729 // scope until later (after the instance variable block), but we want the
730 // diagnostics to occur right after we parse the type parameter list.
731 llvm::SmallDenseMap<IdentifierInfo *, ObjCTypeParamDecl *> knownParams;
732 for (auto typeParam : typeParams) {
733 auto known = knownParams.find(typeParam->getIdentifier());
734 if (known != knownParams.end()) {
735 Diag(typeParam->getLocation(), diag::err_objc_type_param_redecl)
736 << typeParam->getIdentifier()
737 << SourceRange(known->second->getLocation());
739 typeParam->setInvalidDecl();
741 knownParams.insert(std::make_pair(typeParam->getIdentifier(), typeParam));
743 // Push the type parameter into scope.
744 PushOnScopeChains(typeParam, S, /*AddToContext=*/false);
748 // Create the parameter list.
749 return ObjCTypeParamList::create(Context, lAngleLoc, typeParams, rAngleLoc);
752 void Sema::popObjCTypeParamList(Scope *S, ObjCTypeParamList *typeParamList) {
753 for (auto typeParam : *typeParamList) {
754 if (!typeParam->isInvalidDecl()) {
755 S->RemoveDecl(typeParam);
756 IdResolver.RemoveDecl(typeParam);
762 /// The context in which an Objective-C type parameter list occurs, for use
764 enum class TypeParamListContext {
770 } // end anonymous namespace
772 /// Check consistency between two Objective-C type parameter lists, e.g.,
773 /// between a category/extension and an \@interface or between an \@class and an
775 static bool checkTypeParamListConsistency(Sema &S,
776 ObjCTypeParamList *prevTypeParams,
777 ObjCTypeParamList *newTypeParams,
778 TypeParamListContext newContext) {
779 // If the sizes don't match, complain about that.
780 if (prevTypeParams->size() != newTypeParams->size()) {
781 SourceLocation diagLoc;
782 if (newTypeParams->size() > prevTypeParams->size()) {
783 diagLoc = newTypeParams->begin()[prevTypeParams->size()]->getLocation();
785 diagLoc = S.getLocForEndOfToken(newTypeParams->back()->getLocEnd());
788 S.Diag(diagLoc, diag::err_objc_type_param_arity_mismatch)
789 << static_cast<unsigned>(newContext)
790 << (newTypeParams->size() > prevTypeParams->size())
791 << prevTypeParams->size()
792 << newTypeParams->size();
797 // Match up the type parameters.
798 for (unsigned i = 0, n = prevTypeParams->size(); i != n; ++i) {
799 ObjCTypeParamDecl *prevTypeParam = prevTypeParams->begin()[i];
800 ObjCTypeParamDecl *newTypeParam = newTypeParams->begin()[i];
802 // Check for consistency of the variance.
803 if (newTypeParam->getVariance() != prevTypeParam->getVariance()) {
804 if (newTypeParam->getVariance() == ObjCTypeParamVariance::Invariant &&
805 newContext != TypeParamListContext::Definition) {
806 // When the new type parameter is invariant and is not part
807 // of the definition, just propagate the variance.
808 newTypeParam->setVariance(prevTypeParam->getVariance());
809 } else if (prevTypeParam->getVariance()
810 == ObjCTypeParamVariance::Invariant &&
811 !(isa<ObjCInterfaceDecl>(prevTypeParam->getDeclContext()) &&
812 cast<ObjCInterfaceDecl>(prevTypeParam->getDeclContext())
813 ->getDefinition() == prevTypeParam->getDeclContext())) {
814 // When the old parameter is invariant and was not part of the
815 // definition, just ignore the difference because it doesn't
819 // Diagnose the conflict and update the second declaration.
820 SourceLocation diagLoc = newTypeParam->getVarianceLoc();
821 if (diagLoc.isInvalid())
822 diagLoc = newTypeParam->getLocStart();
824 auto diag = S.Diag(diagLoc,
825 diag::err_objc_type_param_variance_conflict)
826 << static_cast<unsigned>(newTypeParam->getVariance())
827 << newTypeParam->getDeclName()
828 << static_cast<unsigned>(prevTypeParam->getVariance())
829 << prevTypeParam->getDeclName();
830 switch (prevTypeParam->getVariance()) {
831 case ObjCTypeParamVariance::Invariant:
832 diag << FixItHint::CreateRemoval(newTypeParam->getVarianceLoc());
835 case ObjCTypeParamVariance::Covariant:
836 case ObjCTypeParamVariance::Contravariant: {
837 StringRef newVarianceStr
838 = prevTypeParam->getVariance() == ObjCTypeParamVariance::Covariant
841 if (newTypeParam->getVariance()
842 == ObjCTypeParamVariance::Invariant) {
843 diag << FixItHint::CreateInsertion(newTypeParam->getLocStart(),
844 (newVarianceStr + " ").str());
846 diag << FixItHint::CreateReplacement(newTypeParam->getVarianceLoc(),
853 S.Diag(prevTypeParam->getLocation(), diag::note_objc_type_param_here)
854 << prevTypeParam->getDeclName();
856 // Override the variance.
857 newTypeParam->setVariance(prevTypeParam->getVariance());
861 // If the bound types match, there's nothing to do.
862 if (S.Context.hasSameType(prevTypeParam->getUnderlyingType(),
863 newTypeParam->getUnderlyingType()))
866 // If the new type parameter's bound was explicit, complain about it being
867 // different from the original.
868 if (newTypeParam->hasExplicitBound()) {
869 SourceRange newBoundRange = newTypeParam->getTypeSourceInfo()
870 ->getTypeLoc().getSourceRange();
871 S.Diag(newBoundRange.getBegin(), diag::err_objc_type_param_bound_conflict)
872 << newTypeParam->getUnderlyingType()
873 << newTypeParam->getDeclName()
874 << prevTypeParam->hasExplicitBound()
875 << prevTypeParam->getUnderlyingType()
876 << (newTypeParam->getDeclName() == prevTypeParam->getDeclName())
877 << prevTypeParam->getDeclName()
878 << FixItHint::CreateReplacement(
880 prevTypeParam->getUnderlyingType().getAsString(
881 S.Context.getPrintingPolicy()));
883 S.Diag(prevTypeParam->getLocation(), diag::note_objc_type_param_here)
884 << prevTypeParam->getDeclName();
886 // Override the new type parameter's bound type with the previous type,
887 // so that it's consistent.
888 newTypeParam->setTypeSourceInfo(
889 S.Context.getTrivialTypeSourceInfo(prevTypeParam->getUnderlyingType()));
893 // The new type parameter got the implicit bound of 'id'. That's okay for
894 // categories and extensions (overwrite it later), but not for forward
895 // declarations and @interfaces, because those must be standalone.
896 if (newContext == TypeParamListContext::ForwardDeclaration ||
897 newContext == TypeParamListContext::Definition) {
898 // Diagnose this problem for forward declarations and definitions.
899 SourceLocation insertionLoc
900 = S.getLocForEndOfToken(newTypeParam->getLocation());
902 = " : " + prevTypeParam->getUnderlyingType().getAsString(
903 S.Context.getPrintingPolicy());
904 S.Diag(newTypeParam->getLocation(),
905 diag::err_objc_type_param_bound_missing)
906 << prevTypeParam->getUnderlyingType()
907 << newTypeParam->getDeclName()
908 << (newContext == TypeParamListContext::ForwardDeclaration)
909 << FixItHint::CreateInsertion(insertionLoc, newCode);
911 S.Diag(prevTypeParam->getLocation(), diag::note_objc_type_param_here)
912 << prevTypeParam->getDeclName();
915 // Update the new type parameter's bound to match the previous one.
916 newTypeParam->setTypeSourceInfo(
917 S.Context.getTrivialTypeSourceInfo(prevTypeParam->getUnderlyingType()));
924 ActOnStartClassInterface(Scope *S, SourceLocation AtInterfaceLoc,
925 IdentifierInfo *ClassName, SourceLocation ClassLoc,
926 ObjCTypeParamList *typeParamList,
927 IdentifierInfo *SuperName, SourceLocation SuperLoc,
928 ArrayRef<ParsedType> SuperTypeArgs,
929 SourceRange SuperTypeArgsRange,
930 Decl * const *ProtoRefs, unsigned NumProtoRefs,
931 const SourceLocation *ProtoLocs,
932 SourceLocation EndProtoLoc, AttributeList *AttrList) {
933 assert(ClassName && "Missing class identifier");
935 // Check for another declaration kind with the same name.
936 NamedDecl *PrevDecl = LookupSingleName(TUScope, ClassName, ClassLoc,
937 LookupOrdinaryName, ForRedeclaration);
939 if (PrevDecl && !isa<ObjCInterfaceDecl>(PrevDecl)) {
940 Diag(ClassLoc, diag::err_redefinition_different_kind) << ClassName;
941 Diag(PrevDecl->getLocation(), diag::note_previous_definition);
944 // Create a declaration to describe this @interface.
945 ObjCInterfaceDecl* PrevIDecl = dyn_cast_or_null<ObjCInterfaceDecl>(PrevDecl);
947 if (PrevIDecl && PrevIDecl->getIdentifier() != ClassName) {
948 // A previous decl with a different name is because of
949 // @compatibility_alias, for example:
952 // @compatibility_alias OldImage NewImage;
954 // A lookup for 'OldImage' will return the 'NewImage' decl.
956 // In such a case use the real declaration name, instead of the alias one,
957 // otherwise we will break IdentifierResolver and redecls-chain invariants.
958 // FIXME: If necessary, add a bit to indicate that this ObjCInterfaceDecl
960 ClassName = PrevIDecl->getIdentifier();
963 // If there was a forward declaration with type parameters, check
966 if (ObjCTypeParamList *prevTypeParamList = PrevIDecl->getTypeParamList()) {
968 // Both have type parameter lists; check for consistency.
969 if (checkTypeParamListConsistency(*this, prevTypeParamList,
971 TypeParamListContext::Definition)) {
972 typeParamList = nullptr;
975 Diag(ClassLoc, diag::err_objc_parameterized_forward_class_first)
977 Diag(prevTypeParamList->getLAngleLoc(), diag::note_previous_decl)
980 // Clone the type parameter list.
981 SmallVector<ObjCTypeParamDecl *, 4> clonedTypeParams;
982 for (auto typeParam : *prevTypeParamList) {
983 clonedTypeParams.push_back(
984 ObjCTypeParamDecl::Create(
987 typeParam->getVariance(),
989 typeParam->getIndex(),
991 typeParam->getIdentifier(),
993 Context.getTrivialTypeSourceInfo(typeParam->getUnderlyingType())));
996 typeParamList = ObjCTypeParamList::create(Context,
1004 ObjCInterfaceDecl *IDecl
1005 = ObjCInterfaceDecl::Create(Context, CurContext, AtInterfaceLoc, ClassName,
1006 typeParamList, PrevIDecl, ClassLoc);
1008 // Class already seen. Was it a definition?
1009 if (ObjCInterfaceDecl *Def = PrevIDecl->getDefinition()) {
1010 Diag(AtInterfaceLoc, diag::err_duplicate_class_def)
1011 << PrevIDecl->getDeclName();
1012 Diag(Def->getLocation(), diag::note_previous_definition);
1013 IDecl->setInvalidDecl();
1018 ProcessDeclAttributeList(TUScope, IDecl, AttrList);
1019 AddPragmaAttributes(TUScope, IDecl);
1020 PushOnScopeChains(IDecl, TUScope);
1022 // Start the definition of this class. If we're in a redefinition case, there
1023 // may already be a definition, so we'll end up adding to it.
1024 if (!IDecl->hasDefinition())
1025 IDecl->startDefinition();
1028 // Diagnose availability in the context of the @interface.
1029 ContextRAII SavedContext(*this, IDecl);
1031 ActOnSuperClassOfClassInterface(S, AtInterfaceLoc, IDecl,
1032 ClassName, ClassLoc,
1033 SuperName, SuperLoc, SuperTypeArgs,
1034 SuperTypeArgsRange);
1035 } else { // we have a root class.
1036 IDecl->setEndOfDefinitionLoc(ClassLoc);
1039 // Check then save referenced protocols.
1041 diagnoseUseOfProtocols(*this, IDecl, (ObjCProtocolDecl*const*)ProtoRefs,
1042 NumProtoRefs, ProtoLocs);
1043 IDecl->setProtocolList((ObjCProtocolDecl*const*)ProtoRefs, NumProtoRefs,
1044 ProtoLocs, Context);
1045 IDecl->setEndOfDefinitionLoc(EndProtoLoc);
1048 CheckObjCDeclScope(IDecl);
1049 return ActOnObjCContainerStartDefinition(IDecl);
1052 /// ActOnTypedefedProtocols - this action finds protocol list as part of the
1053 /// typedef'ed use for a qualified super class and adds them to the list
1054 /// of the protocols.
1055 void Sema::ActOnTypedefedProtocols(SmallVectorImpl<Decl *> &ProtocolRefs,
1056 SmallVectorImpl<SourceLocation> &ProtocolLocs,
1057 IdentifierInfo *SuperName,
1058 SourceLocation SuperLoc) {
1061 NamedDecl* IDecl = LookupSingleName(TUScope, SuperName, SuperLoc,
1062 LookupOrdinaryName);
1066 if (const TypedefNameDecl *TDecl = dyn_cast_or_null<TypedefNameDecl>(IDecl)) {
1067 QualType T = TDecl->getUnderlyingType();
1068 if (T->isObjCObjectType())
1069 if (const ObjCObjectType *OPT = T->getAs<ObjCObjectType>()) {
1070 ProtocolRefs.append(OPT->qual_begin(), OPT->qual_end());
1071 // FIXME: Consider whether this should be an invalid loc since the loc
1072 // is not actually pointing to a protocol name reference but to the
1073 // typedef reference. Note that the base class name loc is also pointing
1075 ProtocolLocs.append(OPT->getNumProtocols(), SuperLoc);
1080 /// ActOnCompatibilityAlias - this action is called after complete parsing of
1081 /// a \@compatibility_alias declaration. It sets up the alias relationships.
1082 Decl *Sema::ActOnCompatibilityAlias(SourceLocation AtLoc,
1083 IdentifierInfo *AliasName,
1084 SourceLocation AliasLocation,
1085 IdentifierInfo *ClassName,
1086 SourceLocation ClassLocation) {
1087 // Look for previous declaration of alias name
1088 NamedDecl *ADecl = LookupSingleName(TUScope, AliasName, AliasLocation,
1089 LookupOrdinaryName, ForRedeclaration);
1091 Diag(AliasLocation, diag::err_conflicting_aliasing_type) << AliasName;
1092 Diag(ADecl->getLocation(), diag::note_previous_declaration);
1095 // Check for class declaration
1096 NamedDecl *CDeclU = LookupSingleName(TUScope, ClassName, ClassLocation,
1097 LookupOrdinaryName, ForRedeclaration);
1098 if (const TypedefNameDecl *TDecl =
1099 dyn_cast_or_null<TypedefNameDecl>(CDeclU)) {
1100 QualType T = TDecl->getUnderlyingType();
1101 if (T->isObjCObjectType()) {
1102 if (NamedDecl *IDecl = T->getAs<ObjCObjectType>()->getInterface()) {
1103 ClassName = IDecl->getIdentifier();
1104 CDeclU = LookupSingleName(TUScope, ClassName, ClassLocation,
1105 LookupOrdinaryName, ForRedeclaration);
1109 ObjCInterfaceDecl *CDecl = dyn_cast_or_null<ObjCInterfaceDecl>(CDeclU);
1111 Diag(ClassLocation, diag::warn_undef_interface) << ClassName;
1113 Diag(CDeclU->getLocation(), diag::note_previous_declaration);
1117 // Everything checked out, instantiate a new alias declaration AST.
1118 ObjCCompatibleAliasDecl *AliasDecl =
1119 ObjCCompatibleAliasDecl::Create(Context, CurContext, AtLoc, AliasName, CDecl);
1121 if (!CheckObjCDeclScope(AliasDecl))
1122 PushOnScopeChains(AliasDecl, TUScope);
1127 bool Sema::CheckForwardProtocolDeclarationForCircularDependency(
1128 IdentifierInfo *PName,
1129 SourceLocation &Ploc, SourceLocation PrevLoc,
1130 const ObjCList<ObjCProtocolDecl> &PList) {
1133 for (ObjCList<ObjCProtocolDecl>::iterator I = PList.begin(),
1134 E = PList.end(); I != E; ++I) {
1135 if (ObjCProtocolDecl *PDecl = LookupProtocol((*I)->getIdentifier(),
1137 if (PDecl->getIdentifier() == PName) {
1138 Diag(Ploc, diag::err_protocol_has_circular_dependency);
1139 Diag(PrevLoc, diag::note_previous_definition);
1143 if (!PDecl->hasDefinition())
1146 if (CheckForwardProtocolDeclarationForCircularDependency(PName, Ploc,
1147 PDecl->getLocation(), PDecl->getReferencedProtocols()))
1155 Sema::ActOnStartProtocolInterface(SourceLocation AtProtoInterfaceLoc,
1156 IdentifierInfo *ProtocolName,
1157 SourceLocation ProtocolLoc,
1158 Decl * const *ProtoRefs,
1159 unsigned NumProtoRefs,
1160 const SourceLocation *ProtoLocs,
1161 SourceLocation EndProtoLoc,
1162 AttributeList *AttrList) {
1164 // FIXME: Deal with AttrList.
1165 assert(ProtocolName && "Missing protocol identifier");
1166 ObjCProtocolDecl *PrevDecl = LookupProtocol(ProtocolName, ProtocolLoc,
1168 ObjCProtocolDecl *PDecl = nullptr;
1169 if (ObjCProtocolDecl *Def = PrevDecl? PrevDecl->getDefinition() : nullptr) {
1170 // If we already have a definition, complain.
1171 Diag(ProtocolLoc, diag::warn_duplicate_protocol_def) << ProtocolName;
1172 Diag(Def->getLocation(), diag::note_previous_definition);
1174 // Create a new protocol that is completely distinct from previous
1175 // declarations, and do not make this protocol available for name lookup.
1176 // That way, we'll end up completely ignoring the duplicate.
1177 // FIXME: Can we turn this into an error?
1178 PDecl = ObjCProtocolDecl::Create(Context, CurContext, ProtocolName,
1179 ProtocolLoc, AtProtoInterfaceLoc,
1180 /*PrevDecl=*/nullptr);
1181 PDecl->startDefinition();
1184 // Check for circular dependencies among protocol declarations. This can
1185 // only happen if this protocol was forward-declared.
1186 ObjCList<ObjCProtocolDecl> PList;
1187 PList.set((ObjCProtocolDecl *const*)ProtoRefs, NumProtoRefs, Context);
1188 err = CheckForwardProtocolDeclarationForCircularDependency(
1189 ProtocolName, ProtocolLoc, PrevDecl->getLocation(), PList);
1192 // Create the new declaration.
1193 PDecl = ObjCProtocolDecl::Create(Context, CurContext, ProtocolName,
1194 ProtocolLoc, AtProtoInterfaceLoc,
1195 /*PrevDecl=*/PrevDecl);
1197 PushOnScopeChains(PDecl, TUScope);
1198 PDecl->startDefinition();
1202 ProcessDeclAttributeList(TUScope, PDecl, AttrList);
1203 AddPragmaAttributes(TUScope, PDecl);
1205 // Merge attributes from previous declarations.
1207 mergeDeclAttributes(PDecl, PrevDecl);
1209 if (!err && NumProtoRefs ) {
1210 /// Check then save referenced protocols.
1211 diagnoseUseOfProtocols(*this, PDecl, (ObjCProtocolDecl*const*)ProtoRefs,
1212 NumProtoRefs, ProtoLocs);
1213 PDecl->setProtocolList((ObjCProtocolDecl*const*)ProtoRefs, NumProtoRefs,
1214 ProtoLocs, Context);
1217 CheckObjCDeclScope(PDecl);
1218 return ActOnObjCContainerStartDefinition(PDecl);
1221 static bool NestedProtocolHasNoDefinition(ObjCProtocolDecl *PDecl,
1222 ObjCProtocolDecl *&UndefinedProtocol) {
1223 if (!PDecl->hasDefinition() || PDecl->getDefinition()->isHidden()) {
1224 UndefinedProtocol = PDecl;
1228 for (auto *PI : PDecl->protocols())
1229 if (NestedProtocolHasNoDefinition(PI, UndefinedProtocol)) {
1230 UndefinedProtocol = PI;
1236 /// FindProtocolDeclaration - This routine looks up protocols and
1237 /// issues an error if they are not declared. It returns list of
1238 /// protocol declarations in its 'Protocols' argument.
1240 Sema::FindProtocolDeclaration(bool WarnOnDeclarations, bool ForObjCContainer,
1241 ArrayRef<IdentifierLocPair> ProtocolId,
1242 SmallVectorImpl<Decl *> &Protocols) {
1243 for (const IdentifierLocPair &Pair : ProtocolId) {
1244 ObjCProtocolDecl *PDecl = LookupProtocol(Pair.first, Pair.second);
1246 TypoCorrection Corrected = CorrectTypo(
1247 DeclarationNameInfo(Pair.first, Pair.second),
1248 LookupObjCProtocolName, TUScope, nullptr,
1249 llvm::make_unique<DeclFilterCCC<ObjCProtocolDecl>>(),
1251 if ((PDecl = Corrected.getCorrectionDeclAs<ObjCProtocolDecl>()))
1252 diagnoseTypo(Corrected, PDiag(diag::err_undeclared_protocol_suggest)
1257 Diag(Pair.second, diag::err_undeclared_protocol) << Pair.first;
1260 // If this is a forward protocol declaration, get its definition.
1261 if (!PDecl->isThisDeclarationADefinition() && PDecl->getDefinition())
1262 PDecl = PDecl->getDefinition();
1264 // For an objc container, delay protocol reference checking until after we
1265 // can set the objc decl as the availability context, otherwise check now.
1266 if (!ForObjCContainer) {
1267 (void)DiagnoseUseOfDecl(PDecl, Pair.second);
1270 // If this is a forward declaration and we are supposed to warn in this
1272 // FIXME: Recover nicely in the hidden case.
1273 ObjCProtocolDecl *UndefinedProtocol;
1275 if (WarnOnDeclarations &&
1276 NestedProtocolHasNoDefinition(PDecl, UndefinedProtocol)) {
1277 Diag(Pair.second, diag::warn_undef_protocolref) << Pair.first;
1278 Diag(UndefinedProtocol->getLocation(), diag::note_protocol_decl_undefined)
1279 << UndefinedProtocol;
1281 Protocols.push_back(PDecl);
1286 // Callback to only accept typo corrections that are either
1287 // Objective-C protocols or valid Objective-C type arguments.
1288 class ObjCTypeArgOrProtocolValidatorCCC : public CorrectionCandidateCallback {
1289 ASTContext &Context;
1290 Sema::LookupNameKind LookupKind;
1292 ObjCTypeArgOrProtocolValidatorCCC(ASTContext &context,
1293 Sema::LookupNameKind lookupKind)
1294 : Context(context), LookupKind(lookupKind) { }
1296 bool ValidateCandidate(const TypoCorrection &candidate) override {
1297 // If we're allowed to find protocols and we have a protocol, accept it.
1298 if (LookupKind != Sema::LookupOrdinaryName) {
1299 if (candidate.getCorrectionDeclAs<ObjCProtocolDecl>())
1303 // If we're allowed to find type names and we have one, accept it.
1304 if (LookupKind != Sema::LookupObjCProtocolName) {
1305 // If we have a type declaration, we might accept this result.
1306 if (auto typeDecl = candidate.getCorrectionDeclAs<TypeDecl>()) {
1307 // If we found a tag declaration outside of C++, skip it. This
1308 // can happy because we look for any name when there is no
1309 // bias to protocol or type names.
1310 if (isa<RecordDecl>(typeDecl) && !Context.getLangOpts().CPlusPlus)
1313 // Make sure the type is something we would accept as a type
1315 auto type = Context.getTypeDeclType(typeDecl);
1316 if (type->isObjCObjectPointerType() ||
1317 type->isBlockPointerType() ||
1318 type->isDependentType() ||
1319 type->isObjCObjectType())
1325 // If we have an Objective-C class type, accept it; there will
1326 // be another fix to add the '*'.
1327 if (candidate.getCorrectionDeclAs<ObjCInterfaceDecl>())
1336 } // end anonymous namespace
1338 void Sema::DiagnoseTypeArgsAndProtocols(IdentifierInfo *ProtocolId,
1339 SourceLocation ProtocolLoc,
1340 IdentifierInfo *TypeArgId,
1341 SourceLocation TypeArgLoc,
1342 bool SelectProtocolFirst) {
1343 Diag(TypeArgLoc, diag::err_objc_type_args_and_protocols)
1344 << SelectProtocolFirst << TypeArgId << ProtocolId
1345 << SourceRange(ProtocolLoc);
1348 void Sema::actOnObjCTypeArgsOrProtocolQualifiers(
1350 ParsedType baseType,
1351 SourceLocation lAngleLoc,
1352 ArrayRef<IdentifierInfo *> identifiers,
1353 ArrayRef<SourceLocation> identifierLocs,
1354 SourceLocation rAngleLoc,
1355 SourceLocation &typeArgsLAngleLoc,
1356 SmallVectorImpl<ParsedType> &typeArgs,
1357 SourceLocation &typeArgsRAngleLoc,
1358 SourceLocation &protocolLAngleLoc,
1359 SmallVectorImpl<Decl *> &protocols,
1360 SourceLocation &protocolRAngleLoc,
1361 bool warnOnIncompleteProtocols) {
1362 // Local function that updates the declaration specifiers with
1363 // protocol information.
1364 unsigned numProtocolsResolved = 0;
1365 auto resolvedAsProtocols = [&] {
1366 assert(numProtocolsResolved == identifiers.size() && "Unresolved protocols");
1368 // Determine whether the base type is a parameterized class, in
1369 // which case we want to warn about typos such as
1370 // "NSArray<NSObject>" (that should be NSArray<NSObject *>).
1371 ObjCInterfaceDecl *baseClass = nullptr;
1372 QualType base = GetTypeFromParser(baseType, nullptr);
1373 bool allAreTypeNames = false;
1374 SourceLocation firstClassNameLoc;
1375 if (!base.isNull()) {
1376 if (const auto *objcObjectType = base->getAs<ObjCObjectType>()) {
1377 baseClass = objcObjectType->getInterface();
1379 if (auto typeParams = baseClass->getTypeParamList()) {
1380 if (typeParams->size() == numProtocolsResolved) {
1381 // Note that we should be looking for type names, too.
1382 allAreTypeNames = true;
1389 for (unsigned i = 0, n = protocols.size(); i != n; ++i) {
1390 ObjCProtocolDecl *&proto
1391 = reinterpret_cast<ObjCProtocolDecl *&>(protocols[i]);
1392 // For an objc container, delay protocol reference checking until after we
1393 // can set the objc decl as the availability context, otherwise check now.
1394 if (!warnOnIncompleteProtocols) {
1395 (void)DiagnoseUseOfDecl(proto, identifierLocs[i]);
1398 // If this is a forward protocol declaration, get its definition.
1399 if (!proto->isThisDeclarationADefinition() && proto->getDefinition())
1400 proto = proto->getDefinition();
1402 // If this is a forward declaration and we are supposed to warn in this
1404 // FIXME: Recover nicely in the hidden case.
1405 ObjCProtocolDecl *forwardDecl = nullptr;
1406 if (warnOnIncompleteProtocols &&
1407 NestedProtocolHasNoDefinition(proto, forwardDecl)) {
1408 Diag(identifierLocs[i], diag::warn_undef_protocolref)
1409 << proto->getDeclName();
1410 Diag(forwardDecl->getLocation(), diag::note_protocol_decl_undefined)
1414 // If everything this far has been a type name (and we care
1415 // about such things), check whether this name refers to a type
1417 if (allAreTypeNames) {
1418 if (auto *decl = LookupSingleName(S, identifiers[i], identifierLocs[i],
1419 LookupOrdinaryName)) {
1420 if (isa<ObjCInterfaceDecl>(decl)) {
1421 if (firstClassNameLoc.isInvalid())
1422 firstClassNameLoc = identifierLocs[i];
1423 } else if (!isa<TypeDecl>(decl)) {
1425 allAreTypeNames = false;
1428 allAreTypeNames = false;
1433 // All of the protocols listed also have type names, and at least
1434 // one is an Objective-C class name. Check whether all of the
1435 // protocol conformances are declared by the base class itself, in
1436 // which case we warn.
1437 if (allAreTypeNames && firstClassNameLoc.isValid()) {
1438 llvm::SmallPtrSet<ObjCProtocolDecl*, 8> knownProtocols;
1439 Context.CollectInheritedProtocols(baseClass, knownProtocols);
1440 bool allProtocolsDeclared = true;
1441 for (auto proto : protocols) {
1442 if (knownProtocols.count(static_cast<ObjCProtocolDecl *>(proto)) == 0) {
1443 allProtocolsDeclared = false;
1448 if (allProtocolsDeclared) {
1449 Diag(firstClassNameLoc, diag::warn_objc_redundant_qualified_class_type)
1450 << baseClass->getDeclName() << SourceRange(lAngleLoc, rAngleLoc)
1451 << FixItHint::CreateInsertion(getLocForEndOfToken(firstClassNameLoc),
1456 protocolLAngleLoc = lAngleLoc;
1457 protocolRAngleLoc = rAngleLoc;
1458 assert(protocols.size() == identifierLocs.size());
1461 // Attempt to resolve all of the identifiers as protocols.
1462 for (unsigned i = 0, n = identifiers.size(); i != n; ++i) {
1463 ObjCProtocolDecl *proto = LookupProtocol(identifiers[i], identifierLocs[i]);
1464 protocols.push_back(proto);
1466 ++numProtocolsResolved;
1469 // If all of the names were protocols, these were protocol qualifiers.
1470 if (numProtocolsResolved == identifiers.size())
1471 return resolvedAsProtocols();
1473 // Attempt to resolve all of the identifiers as type names or
1474 // Objective-C class names. The latter is technically ill-formed,
1475 // but is probably something like \c NSArray<NSView *> missing the
1477 typedef llvm::PointerUnion<TypeDecl *, ObjCInterfaceDecl *> TypeOrClassDecl;
1478 SmallVector<TypeOrClassDecl, 4> typeDecls;
1479 unsigned numTypeDeclsResolved = 0;
1480 for (unsigned i = 0, n = identifiers.size(); i != n; ++i) {
1481 NamedDecl *decl = LookupSingleName(S, identifiers[i], identifierLocs[i],
1482 LookupOrdinaryName);
1484 typeDecls.push_back(TypeOrClassDecl());
1488 if (auto typeDecl = dyn_cast<TypeDecl>(decl)) {
1489 typeDecls.push_back(typeDecl);
1490 ++numTypeDeclsResolved;
1494 if (auto objcClass = dyn_cast<ObjCInterfaceDecl>(decl)) {
1495 typeDecls.push_back(objcClass);
1496 ++numTypeDeclsResolved;
1500 typeDecls.push_back(TypeOrClassDecl());
1503 AttributeFactory attrFactory;
1505 // Local function that forms a reference to the given type or
1506 // Objective-C class declaration.
1507 auto resolveTypeReference = [&](TypeOrClassDecl typeDecl, SourceLocation loc)
1509 // Form declaration specifiers. They simply refer to the type.
1510 DeclSpec DS(attrFactory);
1511 const char* prevSpec; // unused
1512 unsigned diagID; // unused
1514 if (auto *actualTypeDecl = typeDecl.dyn_cast<TypeDecl *>())
1515 type = Context.getTypeDeclType(actualTypeDecl);
1517 type = Context.getObjCInterfaceType(typeDecl.get<ObjCInterfaceDecl *>());
1518 TypeSourceInfo *parsedTSInfo = Context.getTrivialTypeSourceInfo(type, loc);
1519 ParsedType parsedType = CreateParsedType(type, parsedTSInfo);
1520 DS.SetTypeSpecType(DeclSpec::TST_typename, loc, prevSpec, diagID,
1521 parsedType, Context.getPrintingPolicy());
1522 // Use the identifier location for the type source range.
1523 DS.SetRangeStart(loc);
1524 DS.SetRangeEnd(loc);
1526 // Form the declarator.
1527 Declarator D(DS, Declarator::TypeNameContext);
1529 // If we have a typedef of an Objective-C class type that is missing a '*',
1531 if (type->getAs<ObjCInterfaceType>()) {
1532 SourceLocation starLoc = getLocForEndOfToken(loc);
1533 ParsedAttributes parsedAttrs(attrFactory);
1534 D.AddTypeInfo(DeclaratorChunk::getPointer(/*typeQuals=*/0, starLoc,
1543 // Diagnose the missing '*'.
1544 Diag(loc, diag::err_objc_type_arg_missing_star)
1546 << FixItHint::CreateInsertion(starLoc, " *");
1549 // Convert this to a type.
1550 return ActOnTypeName(S, D);
1553 // Local function that updates the declaration specifiers with
1554 // type argument information.
1555 auto resolvedAsTypeDecls = [&] {
1556 // We did not resolve these as protocols.
1559 assert(numTypeDeclsResolved == identifiers.size() && "Unresolved type decl");
1560 // Map type declarations to type arguments.
1561 for (unsigned i = 0, n = identifiers.size(); i != n; ++i) {
1562 // Map type reference to a type.
1563 TypeResult type = resolveTypeReference(typeDecls[i], identifierLocs[i]);
1564 if (!type.isUsable()) {
1569 typeArgs.push_back(type.get());
1572 typeArgsLAngleLoc = lAngleLoc;
1573 typeArgsRAngleLoc = rAngleLoc;
1576 // If all of the identifiers can be resolved as type names or
1577 // Objective-C class names, we have type arguments.
1578 if (numTypeDeclsResolved == identifiers.size())
1579 return resolvedAsTypeDecls();
1581 // Error recovery: some names weren't found, or we have a mix of
1582 // type and protocol names. Go resolve all of the unresolved names
1583 // and complain if we can't find a consistent answer.
1584 LookupNameKind lookupKind = LookupAnyName;
1585 for (unsigned i = 0, n = identifiers.size(); i != n; ++i) {
1586 // If we already have a protocol or type. Check whether it is the
1588 if (protocols[i] || typeDecls[i]) {
1589 // If we haven't figured out whether we want types or protocols
1590 // yet, try to figure it out from this name.
1591 if (lookupKind == LookupAnyName) {
1592 // If this name refers to both a protocol and a type (e.g., \c
1593 // NSObject), don't conclude anything yet.
1594 if (protocols[i] && typeDecls[i])
1597 // Otherwise, let this name decide whether we'll be correcting
1598 // toward types or protocols.
1599 lookupKind = protocols[i] ? LookupObjCProtocolName
1600 : LookupOrdinaryName;
1604 // If we want protocols and we have a protocol, there's nothing
1606 if (lookupKind == LookupObjCProtocolName && protocols[i])
1609 // If we want types and we have a type declaration, there's
1610 // nothing more to do.
1611 if (lookupKind == LookupOrdinaryName && typeDecls[i])
1614 // We have a conflict: some names refer to protocols and others
1616 DiagnoseTypeArgsAndProtocols(identifiers[0], identifierLocs[0],
1617 identifiers[i], identifierLocs[i],
1618 protocols[i] != nullptr);
1625 // Perform typo correction on the name.
1626 TypoCorrection corrected = CorrectTypo(
1627 DeclarationNameInfo(identifiers[i], identifierLocs[i]), lookupKind, S,
1629 llvm::make_unique<ObjCTypeArgOrProtocolValidatorCCC>(Context,
1633 // Did we find a protocol?
1634 if (auto proto = corrected.getCorrectionDeclAs<ObjCProtocolDecl>()) {
1635 diagnoseTypo(corrected,
1636 PDiag(diag::err_undeclared_protocol_suggest)
1638 lookupKind = LookupObjCProtocolName;
1639 protocols[i] = proto;
1640 ++numProtocolsResolved;
1644 // Did we find a type?
1645 if (auto typeDecl = corrected.getCorrectionDeclAs<TypeDecl>()) {
1646 diagnoseTypo(corrected,
1647 PDiag(diag::err_unknown_typename_suggest)
1649 lookupKind = LookupOrdinaryName;
1650 typeDecls[i] = typeDecl;
1651 ++numTypeDeclsResolved;
1655 // Did we find an Objective-C class?
1656 if (auto objcClass = corrected.getCorrectionDeclAs<ObjCInterfaceDecl>()) {
1657 diagnoseTypo(corrected,
1658 PDiag(diag::err_unknown_type_or_class_name_suggest)
1659 << identifiers[i] << true);
1660 lookupKind = LookupOrdinaryName;
1661 typeDecls[i] = objcClass;
1662 ++numTypeDeclsResolved;
1667 // We couldn't find anything.
1668 Diag(identifierLocs[i],
1669 (lookupKind == LookupAnyName ? diag::err_objc_type_arg_missing
1670 : lookupKind == LookupObjCProtocolName ? diag::err_undeclared_protocol
1671 : diag::err_unknown_typename))
1678 // If all of the names were (corrected to) protocols, these were
1679 // protocol qualifiers.
1680 if (numProtocolsResolved == identifiers.size())
1681 return resolvedAsProtocols();
1683 // Otherwise, all of the names were (corrected to) types.
1684 assert(numTypeDeclsResolved == identifiers.size() && "Not all types?");
1685 return resolvedAsTypeDecls();
1688 /// DiagnoseClassExtensionDupMethods - Check for duplicate declaration of
1689 /// a class method in its extension.
1691 void Sema::DiagnoseClassExtensionDupMethods(ObjCCategoryDecl *CAT,
1692 ObjCInterfaceDecl *ID) {
1694 return; // Possibly due to previous error
1696 llvm::DenseMap<Selector, const ObjCMethodDecl*> MethodMap;
1697 for (auto *MD : ID->methods())
1698 MethodMap[MD->getSelector()] = MD;
1700 if (MethodMap.empty())
1702 for (const auto *Method : CAT->methods()) {
1703 const ObjCMethodDecl *&PrevMethod = MethodMap[Method->getSelector()];
1705 (PrevMethod->isInstanceMethod() == Method->isInstanceMethod()) &&
1706 !MatchTwoMethodDeclarations(Method, PrevMethod)) {
1707 Diag(Method->getLocation(), diag::err_duplicate_method_decl)
1708 << Method->getDeclName();
1709 Diag(PrevMethod->getLocation(), diag::note_previous_declaration);
1714 /// ActOnForwardProtocolDeclaration - Handle \@protocol foo;
1715 Sema::DeclGroupPtrTy
1716 Sema::ActOnForwardProtocolDeclaration(SourceLocation AtProtocolLoc,
1717 ArrayRef<IdentifierLocPair> IdentList,
1718 AttributeList *attrList) {
1719 SmallVector<Decl *, 8> DeclsInGroup;
1720 for (const IdentifierLocPair &IdentPair : IdentList) {
1721 IdentifierInfo *Ident = IdentPair.first;
1722 ObjCProtocolDecl *PrevDecl = LookupProtocol(Ident, IdentPair.second,
1724 ObjCProtocolDecl *PDecl
1725 = ObjCProtocolDecl::Create(Context, CurContext, Ident,
1726 IdentPair.second, AtProtocolLoc,
1729 PushOnScopeChains(PDecl, TUScope);
1730 CheckObjCDeclScope(PDecl);
1733 ProcessDeclAttributeList(TUScope, PDecl, attrList);
1734 AddPragmaAttributes(TUScope, PDecl);
1737 mergeDeclAttributes(PDecl, PrevDecl);
1739 DeclsInGroup.push_back(PDecl);
1742 return BuildDeclaratorGroup(DeclsInGroup);
1746 ActOnStartCategoryInterface(SourceLocation AtInterfaceLoc,
1747 IdentifierInfo *ClassName, SourceLocation ClassLoc,
1748 ObjCTypeParamList *typeParamList,
1749 IdentifierInfo *CategoryName,
1750 SourceLocation CategoryLoc,
1751 Decl * const *ProtoRefs,
1752 unsigned NumProtoRefs,
1753 const SourceLocation *ProtoLocs,
1754 SourceLocation EndProtoLoc,
1755 AttributeList *AttrList) {
1756 ObjCCategoryDecl *CDecl;
1757 ObjCInterfaceDecl *IDecl = getObjCInterfaceDecl(ClassName, ClassLoc, true);
1759 /// Check that class of this category is already completely declared.
1762 || RequireCompleteType(ClassLoc, Context.getObjCInterfaceType(IDecl),
1763 diag::err_category_forward_interface,
1764 CategoryName == nullptr)) {
1765 // Create an invalid ObjCCategoryDecl to serve as context for
1766 // the enclosing method declarations. We mark the decl invalid
1767 // to make it clear that this isn't a valid AST.
1768 CDecl = ObjCCategoryDecl::Create(Context, CurContext, AtInterfaceLoc,
1769 ClassLoc, CategoryLoc, CategoryName,
1770 IDecl, typeParamList);
1771 CDecl->setInvalidDecl();
1772 CurContext->addDecl(CDecl);
1775 Diag(ClassLoc, diag::err_undef_interface) << ClassName;
1776 return ActOnObjCContainerStartDefinition(CDecl);
1779 if (!CategoryName && IDecl->getImplementation()) {
1780 Diag(ClassLoc, diag::err_class_extension_after_impl) << ClassName;
1781 Diag(IDecl->getImplementation()->getLocation(),
1782 diag::note_implementation_declared);
1786 /// Check for duplicate interface declaration for this category
1787 if (ObjCCategoryDecl *Previous
1788 = IDecl->FindCategoryDeclaration(CategoryName)) {
1789 // Class extensions can be declared multiple times, categories cannot.
1790 Diag(CategoryLoc, diag::warn_dup_category_def)
1791 << ClassName << CategoryName;
1792 Diag(Previous->getLocation(), diag::note_previous_definition);
1796 // If we have a type parameter list, check it.
1797 if (typeParamList) {
1798 if (auto prevTypeParamList = IDecl->getTypeParamList()) {
1799 if (checkTypeParamListConsistency(*this, prevTypeParamList, typeParamList,
1801 ? TypeParamListContext::Category
1802 : TypeParamListContext::Extension))
1803 typeParamList = nullptr;
1805 Diag(typeParamList->getLAngleLoc(),
1806 diag::err_objc_parameterized_category_nonclass)
1807 << (CategoryName != nullptr)
1809 << typeParamList->getSourceRange();
1811 typeParamList = nullptr;
1815 CDecl = ObjCCategoryDecl::Create(Context, CurContext, AtInterfaceLoc,
1816 ClassLoc, CategoryLoc, CategoryName, IDecl,
1818 // FIXME: PushOnScopeChains?
1819 CurContext->addDecl(CDecl);
1822 diagnoseUseOfProtocols(*this, CDecl, (ObjCProtocolDecl*const*)ProtoRefs,
1823 NumProtoRefs, ProtoLocs);
1824 CDecl->setProtocolList((ObjCProtocolDecl*const*)ProtoRefs, NumProtoRefs,
1825 ProtoLocs, Context);
1826 // Protocols in the class extension belong to the class.
1827 if (CDecl->IsClassExtension())
1828 IDecl->mergeClassExtensionProtocolList((ObjCProtocolDecl*const*)ProtoRefs,
1829 NumProtoRefs, Context);
1833 ProcessDeclAttributeList(TUScope, CDecl, AttrList);
1834 AddPragmaAttributes(TUScope, CDecl);
1836 CheckObjCDeclScope(CDecl);
1837 return ActOnObjCContainerStartDefinition(CDecl);
1840 /// ActOnStartCategoryImplementation - Perform semantic checks on the
1841 /// category implementation declaration and build an ObjCCategoryImplDecl
1843 Decl *Sema::ActOnStartCategoryImplementation(
1844 SourceLocation AtCatImplLoc,
1845 IdentifierInfo *ClassName, SourceLocation ClassLoc,
1846 IdentifierInfo *CatName, SourceLocation CatLoc) {
1847 ObjCInterfaceDecl *IDecl = getObjCInterfaceDecl(ClassName, ClassLoc, true);
1848 ObjCCategoryDecl *CatIDecl = nullptr;
1849 if (IDecl && IDecl->hasDefinition()) {
1850 CatIDecl = IDecl->FindCategoryDeclaration(CatName);
1852 // Category @implementation with no corresponding @interface.
1853 // Create and install one.
1854 CatIDecl = ObjCCategoryDecl::Create(Context, CurContext, AtCatImplLoc,
1857 /*typeParamList=*/nullptr);
1858 CatIDecl->setImplicit();
1862 ObjCCategoryImplDecl *CDecl =
1863 ObjCCategoryImplDecl::Create(Context, CurContext, CatName, IDecl,
1864 ClassLoc, AtCatImplLoc, CatLoc);
1865 /// Check that class of this category is already completely declared.
1867 Diag(ClassLoc, diag::err_undef_interface) << ClassName;
1868 CDecl->setInvalidDecl();
1869 } else if (RequireCompleteType(ClassLoc, Context.getObjCInterfaceType(IDecl),
1870 diag::err_undef_interface)) {
1871 CDecl->setInvalidDecl();
1874 // FIXME: PushOnScopeChains?
1875 CurContext->addDecl(CDecl);
1877 // If the interface has the objc_runtime_visible attribute, we
1878 // cannot implement a category for it.
1879 if (IDecl && IDecl->hasAttr<ObjCRuntimeVisibleAttr>()) {
1880 Diag(ClassLoc, diag::err_objc_runtime_visible_category)
1881 << IDecl->getDeclName();
1884 /// Check that CatName, category name, is not used in another implementation.
1886 if (CatIDecl->getImplementation()) {
1887 Diag(ClassLoc, diag::err_dup_implementation_category) << ClassName
1889 Diag(CatIDecl->getImplementation()->getLocation(),
1890 diag::note_previous_definition);
1891 CDecl->setInvalidDecl();
1893 CatIDecl->setImplementation(CDecl);
1894 // Warn on implementating category of deprecated class under
1895 // -Wdeprecated-implementations flag.
1896 DiagnoseObjCImplementedDeprecations(*this, CatIDecl,
1897 CDecl->getLocation());
1901 CheckObjCDeclScope(CDecl);
1902 return ActOnObjCContainerStartDefinition(CDecl);
1905 Decl *Sema::ActOnStartClassImplementation(
1906 SourceLocation AtClassImplLoc,
1907 IdentifierInfo *ClassName, SourceLocation ClassLoc,
1908 IdentifierInfo *SuperClassname,
1909 SourceLocation SuperClassLoc) {
1910 ObjCInterfaceDecl *IDecl = nullptr;
1911 // Check for another declaration kind with the same name.
1913 = LookupSingleName(TUScope, ClassName, ClassLoc, LookupOrdinaryName,
1915 if (PrevDecl && !isa<ObjCInterfaceDecl>(PrevDecl)) {
1916 Diag(ClassLoc, diag::err_redefinition_different_kind) << ClassName;
1917 Diag(PrevDecl->getLocation(), diag::note_previous_definition);
1918 } else if ((IDecl = dyn_cast_or_null<ObjCInterfaceDecl>(PrevDecl))) {
1919 // FIXME: This will produce an error if the definition of the interface has
1920 // been imported from a module but is not visible.
1921 RequireCompleteType(ClassLoc, Context.getObjCInterfaceType(IDecl),
1922 diag::warn_undef_interface);
1924 // We did not find anything with the name ClassName; try to correct for
1925 // typos in the class name.
1926 TypoCorrection Corrected = CorrectTypo(
1927 DeclarationNameInfo(ClassName, ClassLoc), LookupOrdinaryName, TUScope,
1928 nullptr, llvm::make_unique<ObjCInterfaceValidatorCCC>(), CTK_NonError);
1929 if (Corrected.getCorrectionDeclAs<ObjCInterfaceDecl>()) {
1930 // Suggest the (potentially) correct interface name. Don't provide a
1931 // code-modification hint or use the typo name for recovery, because
1932 // this is just a warning. The program may actually be correct.
1933 diagnoseTypo(Corrected,
1934 PDiag(diag::warn_undef_interface_suggest) << ClassName,
1935 /*ErrorRecovery*/false);
1937 Diag(ClassLoc, diag::warn_undef_interface) << ClassName;
1941 // Check that super class name is valid class name
1942 ObjCInterfaceDecl *SDecl = nullptr;
1943 if (SuperClassname) {
1944 // Check if a different kind of symbol declared in this scope.
1945 PrevDecl = LookupSingleName(TUScope, SuperClassname, SuperClassLoc,
1946 LookupOrdinaryName);
1947 if (PrevDecl && !isa<ObjCInterfaceDecl>(PrevDecl)) {
1948 Diag(SuperClassLoc, diag::err_redefinition_different_kind)
1950 Diag(PrevDecl->getLocation(), diag::note_previous_definition);
1952 SDecl = dyn_cast_or_null<ObjCInterfaceDecl>(PrevDecl);
1953 if (SDecl && !SDecl->hasDefinition())
1956 Diag(SuperClassLoc, diag::err_undef_superclass)
1957 << SuperClassname << ClassName;
1958 else if (IDecl && !declaresSameEntity(IDecl->getSuperClass(), SDecl)) {
1959 // This implementation and its interface do not have the same
1961 Diag(SuperClassLoc, diag::err_conflicting_super_class)
1962 << SDecl->getDeclName();
1963 Diag(SDecl->getLocation(), diag::note_previous_definition);
1969 // Legacy case of @implementation with no corresponding @interface.
1970 // Build, chain & install the interface decl into the identifier.
1972 // FIXME: Do we support attributes on the @implementation? If so we should
1974 IDecl = ObjCInterfaceDecl::Create(Context, CurContext, AtClassImplLoc,
1975 ClassName, /*typeParamList=*/nullptr,
1976 /*PrevDecl=*/nullptr, ClassLoc,
1978 AddPragmaAttributes(TUScope, IDecl);
1979 IDecl->startDefinition();
1981 IDecl->setSuperClass(Context.getTrivialTypeSourceInfo(
1982 Context.getObjCInterfaceType(SDecl),
1984 IDecl->setEndOfDefinitionLoc(SuperClassLoc);
1986 IDecl->setEndOfDefinitionLoc(ClassLoc);
1989 PushOnScopeChains(IDecl, TUScope);
1991 // Mark the interface as being completed, even if it was just as
1993 // declaration; the user cannot reopen it.
1994 if (!IDecl->hasDefinition())
1995 IDecl->startDefinition();
1998 ObjCImplementationDecl* IMPDecl =
1999 ObjCImplementationDecl::Create(Context, CurContext, IDecl, SDecl,
2000 ClassLoc, AtClassImplLoc, SuperClassLoc);
2002 if (CheckObjCDeclScope(IMPDecl))
2003 return ActOnObjCContainerStartDefinition(IMPDecl);
2005 // Check that there is no duplicate implementation of this class.
2006 if (IDecl->getImplementation()) {
2007 // FIXME: Don't leak everything!
2008 Diag(ClassLoc, diag::err_dup_implementation_class) << ClassName;
2009 Diag(IDecl->getImplementation()->getLocation(),
2010 diag::note_previous_definition);
2011 IMPDecl->setInvalidDecl();
2012 } else { // add it to the list.
2013 IDecl->setImplementation(IMPDecl);
2014 PushOnScopeChains(IMPDecl, TUScope);
2015 // Warn on implementating deprecated class under
2016 // -Wdeprecated-implementations flag.
2017 DiagnoseObjCImplementedDeprecations(*this, IDecl, IMPDecl->getLocation());
2020 // If the superclass has the objc_runtime_visible attribute, we
2021 // cannot implement a subclass of it.
2022 if (IDecl->getSuperClass() &&
2023 IDecl->getSuperClass()->hasAttr<ObjCRuntimeVisibleAttr>()) {
2024 Diag(ClassLoc, diag::err_objc_runtime_visible_subclass)
2025 << IDecl->getDeclName()
2026 << IDecl->getSuperClass()->getDeclName();
2029 return ActOnObjCContainerStartDefinition(IMPDecl);
2032 Sema::DeclGroupPtrTy
2033 Sema::ActOnFinishObjCImplementation(Decl *ObjCImpDecl, ArrayRef<Decl *> Decls) {
2034 SmallVector<Decl *, 64> DeclsInGroup;
2035 DeclsInGroup.reserve(Decls.size() + 1);
2037 for (unsigned i = 0, e = Decls.size(); i != e; ++i) {
2038 Decl *Dcl = Decls[i];
2041 if (Dcl->getDeclContext()->isFileContext())
2042 Dcl->setTopLevelDeclInObjCContainer();
2043 DeclsInGroup.push_back(Dcl);
2046 DeclsInGroup.push_back(ObjCImpDecl);
2048 return BuildDeclaratorGroup(DeclsInGroup);
2051 void Sema::CheckImplementationIvars(ObjCImplementationDecl *ImpDecl,
2052 ObjCIvarDecl **ivars, unsigned numIvars,
2053 SourceLocation RBrace) {
2054 assert(ImpDecl && "missing implementation decl");
2055 ObjCInterfaceDecl* IDecl = ImpDecl->getClassInterface();
2058 /// Check case of non-existing \@interface decl.
2059 /// (legacy objective-c \@implementation decl without an \@interface decl).
2060 /// Add implementations's ivar to the synthesize class's ivar list.
2061 if (IDecl->isImplicitInterfaceDecl()) {
2062 IDecl->setEndOfDefinitionLoc(RBrace);
2063 // Add ivar's to class's DeclContext.
2064 for (unsigned i = 0, e = numIvars; i != e; ++i) {
2065 ivars[i]->setLexicalDeclContext(ImpDecl);
2066 IDecl->makeDeclVisibleInContext(ivars[i]);
2067 ImpDecl->addDecl(ivars[i]);
2072 // If implementation has empty ivar list, just return.
2076 assert(ivars && "missing @implementation ivars");
2077 if (LangOpts.ObjCRuntime.isNonFragile()) {
2078 if (ImpDecl->getSuperClass())
2079 Diag(ImpDecl->getLocation(), diag::warn_on_superclass_use);
2080 for (unsigned i = 0; i < numIvars; i++) {
2081 ObjCIvarDecl* ImplIvar = ivars[i];
2082 if (const ObjCIvarDecl *ClsIvar =
2083 IDecl->getIvarDecl(ImplIvar->getIdentifier())) {
2084 Diag(ImplIvar->getLocation(), diag::err_duplicate_ivar_declaration);
2085 Diag(ClsIvar->getLocation(), diag::note_previous_definition);
2088 // Check class extensions (unnamed categories) for duplicate ivars.
2089 for (const auto *CDecl : IDecl->visible_extensions()) {
2090 if (const ObjCIvarDecl *ClsExtIvar =
2091 CDecl->getIvarDecl(ImplIvar->getIdentifier())) {
2092 Diag(ImplIvar->getLocation(), diag::err_duplicate_ivar_declaration);
2093 Diag(ClsExtIvar->getLocation(), diag::note_previous_definition);
2097 // Instance ivar to Implementation's DeclContext.
2098 ImplIvar->setLexicalDeclContext(ImpDecl);
2099 IDecl->makeDeclVisibleInContext(ImplIvar);
2100 ImpDecl->addDecl(ImplIvar);
2104 // Check interface's Ivar list against those in the implementation.
2105 // names and types must match.
2108 ObjCInterfaceDecl::ivar_iterator
2109 IVI = IDecl->ivar_begin(), IVE = IDecl->ivar_end();
2110 for (; numIvars > 0 && IVI != IVE; ++IVI) {
2111 ObjCIvarDecl* ImplIvar = ivars[j++];
2112 ObjCIvarDecl* ClsIvar = *IVI;
2113 assert (ImplIvar && "missing implementation ivar");
2114 assert (ClsIvar && "missing class ivar");
2116 // First, make sure the types match.
2117 if (!Context.hasSameType(ImplIvar->getType(), ClsIvar->getType())) {
2118 Diag(ImplIvar->getLocation(), diag::err_conflicting_ivar_type)
2119 << ImplIvar->getIdentifier()
2120 << ImplIvar->getType() << ClsIvar->getType();
2121 Diag(ClsIvar->getLocation(), diag::note_previous_definition);
2122 } else if (ImplIvar->isBitField() && ClsIvar->isBitField() &&
2123 ImplIvar->getBitWidthValue(Context) !=
2124 ClsIvar->getBitWidthValue(Context)) {
2125 Diag(ImplIvar->getBitWidth()->getLocStart(),
2126 diag::err_conflicting_ivar_bitwidth) << ImplIvar->getIdentifier();
2127 Diag(ClsIvar->getBitWidth()->getLocStart(),
2128 diag::note_previous_definition);
2130 // Make sure the names are identical.
2131 if (ImplIvar->getIdentifier() != ClsIvar->getIdentifier()) {
2132 Diag(ImplIvar->getLocation(), diag::err_conflicting_ivar_name)
2133 << ImplIvar->getIdentifier() << ClsIvar->getIdentifier();
2134 Diag(ClsIvar->getLocation(), diag::note_previous_definition);
2140 Diag(ivars[j]->getLocation(), diag::err_inconsistent_ivar_count);
2141 else if (IVI != IVE)
2142 Diag(IVI->getLocation(), diag::err_inconsistent_ivar_count);
2145 static void WarnUndefinedMethod(Sema &S, SourceLocation ImpLoc,
2146 ObjCMethodDecl *method,
2147 bool &IncompleteImpl,
2149 NamedDecl *NeededFor = nullptr) {
2150 // No point warning no definition of method which is 'unavailable'.
2151 switch (method->getAvailability()) {
2156 // Don't warn about unavailable or not-yet-introduced methods.
2157 case AR_NotYetIntroduced:
2158 case AR_Unavailable:
2162 // FIXME: For now ignore 'IncompleteImpl'.
2163 // Previously we grouped all unimplemented methods under a single
2164 // warning, but some users strongly voiced that they would prefer
2165 // separate warnings. We will give that approach a try, as that
2166 // matches what we do with protocols.
2168 const Sema::SemaDiagnosticBuilder &B = S.Diag(ImpLoc, DiagID);
2174 // Issue a note to the original declaration.
2175 SourceLocation MethodLoc = method->getLocStart();
2176 if (MethodLoc.isValid())
2177 S.Diag(MethodLoc, diag::note_method_declared_at) << method;
2180 /// Determines if type B can be substituted for type A. Returns true if we can
2181 /// guarantee that anything that the user will do to an object of type A can
2182 /// also be done to an object of type B. This is trivially true if the two
2183 /// types are the same, or if B is a subclass of A. It becomes more complex
2184 /// in cases where protocols are involved.
2186 /// Object types in Objective-C describe the minimum requirements for an
2187 /// object, rather than providing a complete description of a type. For
2188 /// example, if A is a subclass of B, then B* may refer to an instance of A.
2189 /// The principle of substitutability means that we may use an instance of A
2190 /// anywhere that we may use an instance of B - it will implement all of the
2191 /// ivars of B and all of the methods of B.
2193 /// This substitutability is important when type checking methods, because
2194 /// the implementation may have stricter type definitions than the interface.
2195 /// The interface specifies minimum requirements, but the implementation may
2196 /// have more accurate ones. For example, a method may privately accept
2197 /// instances of B, but only publish that it accepts instances of A. Any
2198 /// object passed to it will be type checked against B, and so will implicitly
2199 /// by a valid A*. Similarly, a method may return a subclass of the class that
2200 /// it is declared as returning.
2202 /// This is most important when considering subclassing. A method in a
2203 /// subclass must accept any object as an argument that its superclass's
2204 /// implementation accepts. It may, however, accept a more general type
2205 /// without breaking substitutability (i.e. you can still use the subclass
2206 /// anywhere that you can use the superclass, but not vice versa). The
2207 /// converse requirement applies to return types: the return type for a
2208 /// subclass method must be a valid object of the kind that the superclass
2209 /// advertises, but it may be specified more accurately. This avoids the need
2210 /// for explicit down-casting by callers.
2212 /// Note: This is a stricter requirement than for assignment.
2213 static bool isObjCTypeSubstitutable(ASTContext &Context,
2214 const ObjCObjectPointerType *A,
2215 const ObjCObjectPointerType *B,
2217 // Reject a protocol-unqualified id.
2218 if (rejectId && B->isObjCIdType()) return false;
2220 // If B is a qualified id, then A must also be a qualified id and it must
2221 // implement all of the protocols in B. It may not be a qualified class.
2222 // For example, MyClass<A> can be assigned to id<A>, but MyClass<A> is a
2223 // stricter definition so it is not substitutable for id<A>.
2224 if (B->isObjCQualifiedIdType()) {
2225 return A->isObjCQualifiedIdType() &&
2226 Context.ObjCQualifiedIdTypesAreCompatible(QualType(A, 0),
2232 // id is a special type that bypasses type checking completely. We want a
2233 // warning when it is used in one place but not another.
2234 if (C.isObjCIdType(A) || C.isObjCIdType(B)) return false;
2237 // If B is a qualified id, then A must also be a qualified id (which it isn't
2238 // if we've got this far)
2239 if (B->isObjCQualifiedIdType()) return false;
2242 // Now we know that A and B are (potentially-qualified) class types. The
2243 // normal rules for assignment apply.
2244 return Context.canAssignObjCInterfaces(A, B);
2247 static SourceRange getTypeRange(TypeSourceInfo *TSI) {
2248 return (TSI ? TSI->getTypeLoc().getSourceRange() : SourceRange());
2251 /// Determine whether two set of Objective-C declaration qualifiers conflict.
2252 static bool objcModifiersConflict(Decl::ObjCDeclQualifier x,
2253 Decl::ObjCDeclQualifier y) {
2254 return (x & ~Decl::OBJC_TQ_CSNullability) !=
2255 (y & ~Decl::OBJC_TQ_CSNullability);
2258 static bool CheckMethodOverrideReturn(Sema &S,
2259 ObjCMethodDecl *MethodImpl,
2260 ObjCMethodDecl *MethodDecl,
2261 bool IsProtocolMethodDecl,
2262 bool IsOverridingMode,
2264 if (IsProtocolMethodDecl &&
2265 objcModifiersConflict(MethodDecl->getObjCDeclQualifier(),
2266 MethodImpl->getObjCDeclQualifier())) {
2268 S.Diag(MethodImpl->getLocation(),
2270 ? diag::warn_conflicting_overriding_ret_type_modifiers
2271 : diag::warn_conflicting_ret_type_modifiers))
2272 << MethodImpl->getDeclName()
2273 << MethodImpl->getReturnTypeSourceRange();
2274 S.Diag(MethodDecl->getLocation(), diag::note_previous_declaration)
2275 << MethodDecl->getReturnTypeSourceRange();
2280 if (Warn && IsOverridingMode &&
2281 !isa<ObjCImplementationDecl>(MethodImpl->getDeclContext()) &&
2282 !S.Context.hasSameNullabilityTypeQualifier(MethodImpl->getReturnType(),
2283 MethodDecl->getReturnType(),
2285 auto nullabilityMethodImpl =
2286 *MethodImpl->getReturnType()->getNullability(S.Context);
2287 auto nullabilityMethodDecl =
2288 *MethodDecl->getReturnType()->getNullability(S.Context);
2289 S.Diag(MethodImpl->getLocation(),
2290 diag::warn_conflicting_nullability_attr_overriding_ret_types)
2291 << DiagNullabilityKind(
2292 nullabilityMethodImpl,
2293 ((MethodImpl->getObjCDeclQualifier() & Decl::OBJC_TQ_CSNullability)
2295 << DiagNullabilityKind(
2296 nullabilityMethodDecl,
2297 ((MethodDecl->getObjCDeclQualifier() & Decl::OBJC_TQ_CSNullability)
2299 S.Diag(MethodDecl->getLocation(), diag::note_previous_declaration);
2302 if (S.Context.hasSameUnqualifiedType(MethodImpl->getReturnType(),
2303 MethodDecl->getReturnType()))
2309 IsOverridingMode ? diag::warn_conflicting_overriding_ret_types
2310 : diag::warn_conflicting_ret_types;
2312 // Mismatches between ObjC pointers go into a different warning
2313 // category, and sometimes they're even completely whitelisted.
2314 if (const ObjCObjectPointerType *ImplPtrTy =
2315 MethodImpl->getReturnType()->getAs<ObjCObjectPointerType>()) {
2316 if (const ObjCObjectPointerType *IfacePtrTy =
2317 MethodDecl->getReturnType()->getAs<ObjCObjectPointerType>()) {
2318 // Allow non-matching return types as long as they don't violate
2319 // the principle of substitutability. Specifically, we permit
2320 // return types that are subclasses of the declared return type,
2321 // or that are more-qualified versions of the declared type.
2322 if (isObjCTypeSubstitutable(S.Context, IfacePtrTy, ImplPtrTy, false))
2326 IsOverridingMode ? diag::warn_non_covariant_overriding_ret_types
2327 : diag::warn_non_covariant_ret_types;
2331 S.Diag(MethodImpl->getLocation(), DiagID)
2332 << MethodImpl->getDeclName() << MethodDecl->getReturnType()
2333 << MethodImpl->getReturnType()
2334 << MethodImpl->getReturnTypeSourceRange();
2335 S.Diag(MethodDecl->getLocation(), IsOverridingMode
2336 ? diag::note_previous_declaration
2337 : diag::note_previous_definition)
2338 << MethodDecl->getReturnTypeSourceRange();
2342 static bool CheckMethodOverrideParam(Sema &S,
2343 ObjCMethodDecl *MethodImpl,
2344 ObjCMethodDecl *MethodDecl,
2345 ParmVarDecl *ImplVar,
2346 ParmVarDecl *IfaceVar,
2347 bool IsProtocolMethodDecl,
2348 bool IsOverridingMode,
2350 if (IsProtocolMethodDecl &&
2351 objcModifiersConflict(ImplVar->getObjCDeclQualifier(),
2352 IfaceVar->getObjCDeclQualifier())) {
2354 if (IsOverridingMode)
2355 S.Diag(ImplVar->getLocation(),
2356 diag::warn_conflicting_overriding_param_modifiers)
2357 << getTypeRange(ImplVar->getTypeSourceInfo())
2358 << MethodImpl->getDeclName();
2359 else S.Diag(ImplVar->getLocation(),
2360 diag::warn_conflicting_param_modifiers)
2361 << getTypeRange(ImplVar->getTypeSourceInfo())
2362 << MethodImpl->getDeclName();
2363 S.Diag(IfaceVar->getLocation(), diag::note_previous_declaration)
2364 << getTypeRange(IfaceVar->getTypeSourceInfo());
2370 QualType ImplTy = ImplVar->getType();
2371 QualType IfaceTy = IfaceVar->getType();
2372 if (Warn && IsOverridingMode &&
2373 !isa<ObjCImplementationDecl>(MethodImpl->getDeclContext()) &&
2374 !S.Context.hasSameNullabilityTypeQualifier(ImplTy, IfaceTy, true)) {
2375 S.Diag(ImplVar->getLocation(),
2376 diag::warn_conflicting_nullability_attr_overriding_param_types)
2377 << DiagNullabilityKind(
2378 *ImplTy->getNullability(S.Context),
2379 ((ImplVar->getObjCDeclQualifier() & Decl::OBJC_TQ_CSNullability)
2381 << DiagNullabilityKind(
2382 *IfaceTy->getNullability(S.Context),
2383 ((IfaceVar->getObjCDeclQualifier() & Decl::OBJC_TQ_CSNullability)
2385 S.Diag(IfaceVar->getLocation(), diag::note_previous_declaration);
2387 if (S.Context.hasSameUnqualifiedType(ImplTy, IfaceTy))
2393 IsOverridingMode ? diag::warn_conflicting_overriding_param_types
2394 : diag::warn_conflicting_param_types;
2396 // Mismatches between ObjC pointers go into a different warning
2397 // category, and sometimes they're even completely whitelisted.
2398 if (const ObjCObjectPointerType *ImplPtrTy =
2399 ImplTy->getAs<ObjCObjectPointerType>()) {
2400 if (const ObjCObjectPointerType *IfacePtrTy =
2401 IfaceTy->getAs<ObjCObjectPointerType>()) {
2402 // Allow non-matching argument types as long as they don't
2403 // violate the principle of substitutability. Specifically, the
2404 // implementation must accept any objects that the superclass
2405 // accepts, however it may also accept others.
2406 if (isObjCTypeSubstitutable(S.Context, ImplPtrTy, IfacePtrTy, true))
2410 IsOverridingMode ? diag::warn_non_contravariant_overriding_param_types
2411 : diag::warn_non_contravariant_param_types;
2415 S.Diag(ImplVar->getLocation(), DiagID)
2416 << getTypeRange(ImplVar->getTypeSourceInfo())
2417 << MethodImpl->getDeclName() << IfaceTy << ImplTy;
2418 S.Diag(IfaceVar->getLocation(),
2419 (IsOverridingMode ? diag::note_previous_declaration
2420 : diag::note_previous_definition))
2421 << getTypeRange(IfaceVar->getTypeSourceInfo());
2425 /// In ARC, check whether the conventional meanings of the two methods
2426 /// match. If they don't, it's a hard error.
2427 static bool checkMethodFamilyMismatch(Sema &S, ObjCMethodDecl *impl,
2428 ObjCMethodDecl *decl) {
2429 ObjCMethodFamily implFamily = impl->getMethodFamily();
2430 ObjCMethodFamily declFamily = decl->getMethodFamily();
2431 if (implFamily == declFamily) return false;
2433 // Since conventions are sorted by selector, the only possibility is
2434 // that the types differ enough to cause one selector or the other
2435 // to fall out of the family.
2436 assert(implFamily == OMF_None || declFamily == OMF_None);
2438 // No further diagnostics required on invalid declarations.
2439 if (impl->isInvalidDecl() || decl->isInvalidDecl()) return true;
2441 const ObjCMethodDecl *unmatched = impl;
2442 ObjCMethodFamily family = declFamily;
2443 unsigned errorID = diag::err_arc_lost_method_convention;
2444 unsigned noteID = diag::note_arc_lost_method_convention;
2445 if (declFamily == OMF_None) {
2447 family = implFamily;
2448 errorID = diag::err_arc_gained_method_convention;
2449 noteID = diag::note_arc_gained_method_convention;
2452 // Indexes into a %select clause in the diagnostic.
2453 enum FamilySelector {
2454 F_alloc, F_copy, F_mutableCopy = F_copy, F_init, F_new
2456 FamilySelector familySelector = FamilySelector();
2459 case OMF_None: llvm_unreachable("logic error, no method convention");
2462 case OMF_autorelease:
2465 case OMF_retainCount:
2467 case OMF_initialize:
2468 case OMF_performSelector:
2469 // Mismatches for these methods don't change ownership
2470 // conventions, so we don't care.
2473 case OMF_init: familySelector = F_init; break;
2474 case OMF_alloc: familySelector = F_alloc; break;
2475 case OMF_copy: familySelector = F_copy; break;
2476 case OMF_mutableCopy: familySelector = F_mutableCopy; break;
2477 case OMF_new: familySelector = F_new; break;
2480 enum ReasonSelector { R_NonObjectReturn, R_UnrelatedReturn };
2481 ReasonSelector reasonSelector;
2483 // The only reason these methods don't fall within their families is
2484 // due to unusual result types.
2485 if (unmatched->getReturnType()->isObjCObjectPointerType()) {
2486 reasonSelector = R_UnrelatedReturn;
2488 reasonSelector = R_NonObjectReturn;
2491 S.Diag(impl->getLocation(), errorID) << int(familySelector) << int(reasonSelector);
2492 S.Diag(decl->getLocation(), noteID) << int(familySelector) << int(reasonSelector);
2497 void Sema::WarnConflictingTypedMethods(ObjCMethodDecl *ImpMethodDecl,
2498 ObjCMethodDecl *MethodDecl,
2499 bool IsProtocolMethodDecl) {
2500 if (getLangOpts().ObjCAutoRefCount &&
2501 checkMethodFamilyMismatch(*this, ImpMethodDecl, MethodDecl))
2504 CheckMethodOverrideReturn(*this, ImpMethodDecl, MethodDecl,
2505 IsProtocolMethodDecl, false,
2508 for (ObjCMethodDecl::param_iterator IM = ImpMethodDecl->param_begin(),
2509 IF = MethodDecl->param_begin(), EM = ImpMethodDecl->param_end(),
2510 EF = MethodDecl->param_end();
2511 IM != EM && IF != EF; ++IM, ++IF) {
2512 CheckMethodOverrideParam(*this, ImpMethodDecl, MethodDecl, *IM, *IF,
2513 IsProtocolMethodDecl, false, true);
2516 if (ImpMethodDecl->isVariadic() != MethodDecl->isVariadic()) {
2517 Diag(ImpMethodDecl->getLocation(),
2518 diag::warn_conflicting_variadic);
2519 Diag(MethodDecl->getLocation(), diag::note_previous_declaration);
2523 void Sema::CheckConflictingOverridingMethod(ObjCMethodDecl *Method,
2524 ObjCMethodDecl *Overridden,
2525 bool IsProtocolMethodDecl) {
2527 CheckMethodOverrideReturn(*this, Method, Overridden,
2528 IsProtocolMethodDecl, true,
2531 for (ObjCMethodDecl::param_iterator IM = Method->param_begin(),
2532 IF = Overridden->param_begin(), EM = Method->param_end(),
2533 EF = Overridden->param_end();
2534 IM != EM && IF != EF; ++IM, ++IF) {
2535 CheckMethodOverrideParam(*this, Method, Overridden, *IM, *IF,
2536 IsProtocolMethodDecl, true, true);
2539 if (Method->isVariadic() != Overridden->isVariadic()) {
2540 Diag(Method->getLocation(),
2541 diag::warn_conflicting_overriding_variadic);
2542 Diag(Overridden->getLocation(), diag::note_previous_declaration);
2546 /// WarnExactTypedMethods - This routine issues a warning if method
2547 /// implementation declaration matches exactly that of its declaration.
2548 void Sema::WarnExactTypedMethods(ObjCMethodDecl *ImpMethodDecl,
2549 ObjCMethodDecl *MethodDecl,
2550 bool IsProtocolMethodDecl) {
2551 // don't issue warning when protocol method is optional because primary
2552 // class is not required to implement it and it is safe for protocol
2554 if (MethodDecl->getImplementationControl() == ObjCMethodDecl::Optional)
2556 // don't issue warning when primary class's method is
2557 // depecated/unavailable.
2558 if (MethodDecl->hasAttr<UnavailableAttr>() ||
2559 MethodDecl->hasAttr<DeprecatedAttr>())
2562 bool match = CheckMethodOverrideReturn(*this, ImpMethodDecl, MethodDecl,
2563 IsProtocolMethodDecl, false, false);
2565 for (ObjCMethodDecl::param_iterator IM = ImpMethodDecl->param_begin(),
2566 IF = MethodDecl->param_begin(), EM = ImpMethodDecl->param_end(),
2567 EF = MethodDecl->param_end();
2568 IM != EM && IF != EF; ++IM, ++IF) {
2569 match = CheckMethodOverrideParam(*this, ImpMethodDecl, MethodDecl,
2571 IsProtocolMethodDecl, false, false);
2576 match = (ImpMethodDecl->isVariadic() == MethodDecl->isVariadic());
2578 match = !(MethodDecl->isClassMethod() &&
2579 MethodDecl->getSelector() == GetNullarySelector("load", Context));
2582 Diag(ImpMethodDecl->getLocation(),
2583 diag::warn_category_method_impl_match);
2584 Diag(MethodDecl->getLocation(), diag::note_method_declared_at)
2585 << MethodDecl->getDeclName();
2589 /// FIXME: Type hierarchies in Objective-C can be deep. We could most likely
2590 /// improve the efficiency of selector lookups and type checking by associating
2591 /// with each protocol / interface / category the flattened instance tables. If
2592 /// we used an immutable set to keep the table then it wouldn't add significant
2593 /// memory cost and it would be handy for lookups.
2595 typedef llvm::DenseSet<IdentifierInfo*> ProtocolNameSet;
2596 typedef std::unique_ptr<ProtocolNameSet> LazyProtocolNameSet;
2598 static void findProtocolsWithExplicitImpls(const ObjCProtocolDecl *PDecl,
2599 ProtocolNameSet &PNS) {
2600 if (PDecl->hasAttr<ObjCExplicitProtocolImplAttr>())
2601 PNS.insert(PDecl->getIdentifier());
2602 for (const auto *PI : PDecl->protocols())
2603 findProtocolsWithExplicitImpls(PI, PNS);
2606 /// Recursively populates a set with all conformed protocols in a class
2607 /// hierarchy that have the 'objc_protocol_requires_explicit_implementation'
2609 static void findProtocolsWithExplicitImpls(const ObjCInterfaceDecl *Super,
2610 ProtocolNameSet &PNS) {
2614 for (const auto *I : Super->all_referenced_protocols())
2615 findProtocolsWithExplicitImpls(I, PNS);
2617 findProtocolsWithExplicitImpls(Super->getSuperClass(), PNS);
2620 /// CheckProtocolMethodDefs - This routine checks unimplemented methods
2621 /// Declared in protocol, and those referenced by it.
2622 static void CheckProtocolMethodDefs(Sema &S,
2623 SourceLocation ImpLoc,
2624 ObjCProtocolDecl *PDecl,
2625 bool& IncompleteImpl,
2626 const Sema::SelectorSet &InsMap,
2627 const Sema::SelectorSet &ClsMap,
2628 ObjCContainerDecl *CDecl,
2629 LazyProtocolNameSet &ProtocolsExplictImpl) {
2630 ObjCCategoryDecl *C = dyn_cast<ObjCCategoryDecl>(CDecl);
2631 ObjCInterfaceDecl *IDecl = C ? C->getClassInterface()
2632 : dyn_cast<ObjCInterfaceDecl>(CDecl);
2633 assert (IDecl && "CheckProtocolMethodDefs - IDecl is null");
2635 ObjCInterfaceDecl *Super = IDecl->getSuperClass();
2636 ObjCInterfaceDecl *NSIDecl = nullptr;
2638 // If this protocol is marked 'objc_protocol_requires_explicit_implementation'
2639 // then we should check if any class in the super class hierarchy also
2640 // conforms to this protocol, either directly or via protocol inheritance.
2641 // If so, we can skip checking this protocol completely because we
2642 // know that a parent class already satisfies this protocol.
2644 // Note: we could generalize this logic for all protocols, and merely
2645 // add the limit on looking at the super class chain for just
2646 // specially marked protocols. This may be a good optimization. This
2647 // change is restricted to 'objc_protocol_requires_explicit_implementation'
2648 // protocols for now for controlled evaluation.
2649 if (PDecl->hasAttr<ObjCExplicitProtocolImplAttr>()) {
2650 if (!ProtocolsExplictImpl) {
2651 ProtocolsExplictImpl.reset(new ProtocolNameSet);
2652 findProtocolsWithExplicitImpls(Super, *ProtocolsExplictImpl);
2654 if (ProtocolsExplictImpl->find(PDecl->getIdentifier()) !=
2655 ProtocolsExplictImpl->end())
2658 // If no super class conforms to the protocol, we should not search
2659 // for methods in the super class to implicitly satisfy the protocol.
2663 if (S.getLangOpts().ObjCRuntime.isNeXTFamily()) {
2664 // check to see if class implements forwardInvocation method and objects
2665 // of this class are derived from 'NSProxy' so that to forward requests
2666 // from one object to another.
2667 // Under such conditions, which means that every method possible is
2668 // implemented in the class, we should not issue "Method definition not
2670 // FIXME: Use a general GetUnarySelector method for this.
2671 IdentifierInfo* II = &S.Context.Idents.get("forwardInvocation");
2672 Selector fISelector = S.Context.Selectors.getSelector(1, &II);
2673 if (InsMap.count(fISelector))
2674 // Is IDecl derived from 'NSProxy'? If so, no instance methods
2675 // need be implemented in the implementation.
2676 NSIDecl = IDecl->lookupInheritedClass(&S.Context.Idents.get("NSProxy"));
2679 // If this is a forward protocol declaration, get its definition.
2680 if (!PDecl->isThisDeclarationADefinition() &&
2681 PDecl->getDefinition())
2682 PDecl = PDecl->getDefinition();
2684 // If a method lookup fails locally we still need to look and see if
2685 // the method was implemented by a base class or an inherited
2686 // protocol. This lookup is slow, but occurs rarely in correct code
2687 // and otherwise would terminate in a warning.
2689 // check unimplemented instance methods.
2691 for (auto *method : PDecl->instance_methods()) {
2692 if (method->getImplementationControl() != ObjCMethodDecl::Optional &&
2693 !method->isPropertyAccessor() &&
2694 !InsMap.count(method->getSelector()) &&
2695 (!Super || !Super->lookupMethod(method->getSelector(),
2696 true /* instance */,
2697 false /* shallowCategory */,
2698 true /* followsSuper */,
2699 nullptr /* category */))) {
2700 // If a method is not implemented in the category implementation but
2701 // has been declared in its primary class, superclass,
2702 // or in one of their protocols, no need to issue the warning.
2703 // This is because method will be implemented in the primary class
2704 // or one of its super class implementation.
2706 // Ugly, but necessary. Method declared in protcol might have
2707 // have been synthesized due to a property declared in the class which
2708 // uses the protocol.
2709 if (ObjCMethodDecl *MethodInClass =
2710 IDecl->lookupMethod(method->getSelector(),
2711 true /* instance */,
2712 true /* shallowCategoryLookup */,
2713 false /* followSuper */))
2714 if (C || MethodInClass->isPropertyAccessor())
2716 unsigned DIAG = diag::warn_unimplemented_protocol_method;
2717 if (!S.Diags.isIgnored(DIAG, ImpLoc)) {
2718 WarnUndefinedMethod(S, ImpLoc, method, IncompleteImpl, DIAG,
2723 // check unimplemented class methods
2724 for (auto *method : PDecl->class_methods()) {
2725 if (method->getImplementationControl() != ObjCMethodDecl::Optional &&
2726 !ClsMap.count(method->getSelector()) &&
2727 (!Super || !Super->lookupMethod(method->getSelector(),
2728 false /* class method */,
2729 false /* shallowCategoryLookup */,
2730 true /* followSuper */,
2731 nullptr /* category */))) {
2732 // See above comment for instance method lookups.
2733 if (C && IDecl->lookupMethod(method->getSelector(),
2735 true /* shallowCategoryLookup */,
2736 false /* followSuper */))
2739 unsigned DIAG = diag::warn_unimplemented_protocol_method;
2740 if (!S.Diags.isIgnored(DIAG, ImpLoc)) {
2741 WarnUndefinedMethod(S, ImpLoc, method, IncompleteImpl, DIAG, PDecl);
2745 // Check on this protocols's referenced protocols, recursively.
2746 for (auto *PI : PDecl->protocols())
2747 CheckProtocolMethodDefs(S, ImpLoc, PI, IncompleteImpl, InsMap, ClsMap,
2748 CDecl, ProtocolsExplictImpl);
2751 /// MatchAllMethodDeclarations - Check methods declared in interface
2752 /// or protocol against those declared in their implementations.
2754 void Sema::MatchAllMethodDeclarations(const SelectorSet &InsMap,
2755 const SelectorSet &ClsMap,
2756 SelectorSet &InsMapSeen,
2757 SelectorSet &ClsMapSeen,
2758 ObjCImplDecl* IMPDecl,
2759 ObjCContainerDecl* CDecl,
2760 bool &IncompleteImpl,
2761 bool ImmediateClass,
2762 bool WarnCategoryMethodImpl) {
2763 // Check and see if instance methods in class interface have been
2764 // implemented in the implementation class. If so, their types match.
2765 for (auto *I : CDecl->instance_methods()) {
2766 if (!InsMapSeen.insert(I->getSelector()).second)
2768 if (!I->isPropertyAccessor() &&
2769 !InsMap.count(I->getSelector())) {
2771 WarnUndefinedMethod(*this, IMPDecl->getLocation(), I, IncompleteImpl,
2772 diag::warn_undef_method_impl);
2775 ObjCMethodDecl *ImpMethodDecl =
2776 IMPDecl->getInstanceMethod(I->getSelector());
2777 assert(CDecl->getInstanceMethod(I->getSelector(), true/*AllowHidden*/) &&
2778 "Expected to find the method through lookup as well");
2779 // ImpMethodDecl may be null as in a @dynamic property.
2780 if (ImpMethodDecl) {
2781 if (!WarnCategoryMethodImpl)
2782 WarnConflictingTypedMethods(ImpMethodDecl, I,
2783 isa<ObjCProtocolDecl>(CDecl));
2784 else if (!I->isPropertyAccessor())
2785 WarnExactTypedMethods(ImpMethodDecl, I, isa<ObjCProtocolDecl>(CDecl));
2790 // Check and see if class methods in class interface have been
2791 // implemented in the implementation class. If so, their types match.
2792 for (auto *I : CDecl->class_methods()) {
2793 if (!ClsMapSeen.insert(I->getSelector()).second)
2795 if (!I->isPropertyAccessor() &&
2796 !ClsMap.count(I->getSelector())) {
2798 WarnUndefinedMethod(*this, IMPDecl->getLocation(), I, IncompleteImpl,
2799 diag::warn_undef_method_impl);
2801 ObjCMethodDecl *ImpMethodDecl =
2802 IMPDecl->getClassMethod(I->getSelector());
2803 assert(CDecl->getClassMethod(I->getSelector(), true/*AllowHidden*/) &&
2804 "Expected to find the method through lookup as well");
2805 // ImpMethodDecl may be null as in a @dynamic property.
2806 if (ImpMethodDecl) {
2807 if (!WarnCategoryMethodImpl)
2808 WarnConflictingTypedMethods(ImpMethodDecl, I,
2809 isa<ObjCProtocolDecl>(CDecl));
2810 else if (!I->isPropertyAccessor())
2811 WarnExactTypedMethods(ImpMethodDecl, I, isa<ObjCProtocolDecl>(CDecl));
2816 if (ObjCProtocolDecl *PD = dyn_cast<ObjCProtocolDecl> (CDecl)) {
2817 // Also, check for methods declared in protocols inherited by
2819 for (auto *PI : PD->protocols())
2820 MatchAllMethodDeclarations(InsMap, ClsMap, InsMapSeen, ClsMapSeen,
2821 IMPDecl, PI, IncompleteImpl, false,
2822 WarnCategoryMethodImpl);
2825 if (ObjCInterfaceDecl *I = dyn_cast<ObjCInterfaceDecl> (CDecl)) {
2826 // when checking that methods in implementation match their declaration,
2827 // i.e. when WarnCategoryMethodImpl is false, check declarations in class
2828 // extension; as well as those in categories.
2829 if (!WarnCategoryMethodImpl) {
2830 for (auto *Cat : I->visible_categories())
2831 MatchAllMethodDeclarations(InsMap, ClsMap, InsMapSeen, ClsMapSeen,
2832 IMPDecl, Cat, IncompleteImpl,
2833 ImmediateClass && Cat->IsClassExtension(),
2834 WarnCategoryMethodImpl);
2836 // Also methods in class extensions need be looked at next.
2837 for (auto *Ext : I->visible_extensions())
2838 MatchAllMethodDeclarations(InsMap, ClsMap, InsMapSeen, ClsMapSeen,
2839 IMPDecl, Ext, IncompleteImpl, false,
2840 WarnCategoryMethodImpl);
2843 // Check for any implementation of a methods declared in protocol.
2844 for (auto *PI : I->all_referenced_protocols())
2845 MatchAllMethodDeclarations(InsMap, ClsMap, InsMapSeen, ClsMapSeen,
2846 IMPDecl, PI, IncompleteImpl, false,
2847 WarnCategoryMethodImpl);
2849 // FIXME. For now, we are not checking for extact match of methods
2850 // in category implementation and its primary class's super class.
2851 if (!WarnCategoryMethodImpl && I->getSuperClass())
2852 MatchAllMethodDeclarations(InsMap, ClsMap, InsMapSeen, ClsMapSeen,
2854 I->getSuperClass(), IncompleteImpl, false);
2858 /// CheckCategoryVsClassMethodMatches - Checks that methods implemented in
2859 /// category matches with those implemented in its primary class and
2860 /// warns each time an exact match is found.
2861 void Sema::CheckCategoryVsClassMethodMatches(
2862 ObjCCategoryImplDecl *CatIMPDecl) {
2863 // Get category's primary class.
2864 ObjCCategoryDecl *CatDecl = CatIMPDecl->getCategoryDecl();
2867 ObjCInterfaceDecl *IDecl = CatDecl->getClassInterface();
2870 ObjCInterfaceDecl *SuperIDecl = IDecl->getSuperClass();
2871 SelectorSet InsMap, ClsMap;
2873 for (const auto *I : CatIMPDecl->instance_methods()) {
2874 Selector Sel = I->getSelector();
2875 // When checking for methods implemented in the category, skip over
2876 // those declared in category class's super class. This is because
2877 // the super class must implement the method.
2878 if (SuperIDecl && SuperIDecl->lookupMethod(Sel, true))
2883 for (const auto *I : CatIMPDecl->class_methods()) {
2884 Selector Sel = I->getSelector();
2885 if (SuperIDecl && SuperIDecl->lookupMethod(Sel, false))
2889 if (InsMap.empty() && ClsMap.empty())
2892 SelectorSet InsMapSeen, ClsMapSeen;
2893 bool IncompleteImpl = false;
2894 MatchAllMethodDeclarations(InsMap, ClsMap, InsMapSeen, ClsMapSeen,
2896 IncompleteImpl, false,
2897 true /*WarnCategoryMethodImpl*/);
2900 void Sema::ImplMethodsVsClassMethods(Scope *S, ObjCImplDecl* IMPDecl,
2901 ObjCContainerDecl* CDecl,
2902 bool IncompleteImpl) {
2904 // Check and see if instance methods in class interface have been
2905 // implemented in the implementation class.
2906 for (const auto *I : IMPDecl->instance_methods())
2907 InsMap.insert(I->getSelector());
2909 // Add the selectors for getters/setters of @dynamic properties.
2910 for (const auto *PImpl : IMPDecl->property_impls()) {
2911 // We only care about @dynamic implementations.
2912 if (PImpl->getPropertyImplementation() != ObjCPropertyImplDecl::Dynamic)
2915 const auto *P = PImpl->getPropertyDecl();
2918 InsMap.insert(P->getGetterName());
2919 if (!P->getSetterName().isNull())
2920 InsMap.insert(P->getSetterName());
2923 // Check and see if properties declared in the interface have either 1)
2924 // an implementation or 2) there is a @synthesize/@dynamic implementation
2925 // of the property in the @implementation.
2926 if (const ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(CDecl)) {
2927 bool SynthesizeProperties = LangOpts.ObjCDefaultSynthProperties &&
2928 LangOpts.ObjCRuntime.isNonFragile() &&
2929 !IDecl->isObjCRequiresPropertyDefs();
2930 DiagnoseUnimplementedProperties(S, IMPDecl, CDecl, SynthesizeProperties);
2933 // Diagnose null-resettable synthesized setters.
2934 diagnoseNullResettableSynthesizedSetters(IMPDecl);
2937 for (const auto *I : IMPDecl->class_methods())
2938 ClsMap.insert(I->getSelector());
2940 // Check for type conflict of methods declared in a class/protocol and
2941 // its implementation; if any.
2942 SelectorSet InsMapSeen, ClsMapSeen;
2943 MatchAllMethodDeclarations(InsMap, ClsMap, InsMapSeen, ClsMapSeen,
2945 IncompleteImpl, true);
2947 // check all methods implemented in category against those declared
2948 // in its primary class.
2949 if (ObjCCategoryImplDecl *CatDecl =
2950 dyn_cast<ObjCCategoryImplDecl>(IMPDecl))
2951 CheckCategoryVsClassMethodMatches(CatDecl);
2953 // Check the protocol list for unimplemented methods in the @implementation
2955 // Check and see if class methods in class interface have been
2956 // implemented in the implementation class.
2958 LazyProtocolNameSet ExplicitImplProtocols;
2960 if (ObjCInterfaceDecl *I = dyn_cast<ObjCInterfaceDecl> (CDecl)) {
2961 for (auto *PI : I->all_referenced_protocols())
2962 CheckProtocolMethodDefs(*this, IMPDecl->getLocation(), PI, IncompleteImpl,
2963 InsMap, ClsMap, I, ExplicitImplProtocols);
2964 } else if (ObjCCategoryDecl *C = dyn_cast<ObjCCategoryDecl>(CDecl)) {
2965 // For extended class, unimplemented methods in its protocols will
2966 // be reported in the primary class.
2967 if (!C->IsClassExtension()) {
2968 for (auto *P : C->protocols())
2969 CheckProtocolMethodDefs(*this, IMPDecl->getLocation(), P,
2970 IncompleteImpl, InsMap, ClsMap, CDecl,
2971 ExplicitImplProtocols);
2972 DiagnoseUnimplementedProperties(S, IMPDecl, CDecl,
2973 /*SynthesizeProperties=*/false);
2976 llvm_unreachable("invalid ObjCContainerDecl type.");
2979 Sema::DeclGroupPtrTy
2980 Sema::ActOnForwardClassDeclaration(SourceLocation AtClassLoc,
2981 IdentifierInfo **IdentList,
2982 SourceLocation *IdentLocs,
2983 ArrayRef<ObjCTypeParamList *> TypeParamLists,
2985 SmallVector<Decl *, 8> DeclsInGroup;
2986 for (unsigned i = 0; i != NumElts; ++i) {
2987 // Check for another declaration kind with the same name.
2989 = LookupSingleName(TUScope, IdentList[i], IdentLocs[i],
2990 LookupOrdinaryName, ForRedeclaration);
2991 if (PrevDecl && !isa<ObjCInterfaceDecl>(PrevDecl)) {
2992 // GCC apparently allows the following idiom:
2994 // typedef NSObject < XCElementTogglerP > XCElementToggler;
2995 // @class XCElementToggler;
2997 // Here we have chosen to ignore the forward class declaration
2998 // with a warning. Since this is the implied behavior.
2999 TypedefNameDecl *TDD = dyn_cast<TypedefNameDecl>(PrevDecl);
3000 if (!TDD || !TDD->getUnderlyingType()->isObjCObjectType()) {
3001 Diag(AtClassLoc, diag::err_redefinition_different_kind) << IdentList[i];
3002 Diag(PrevDecl->getLocation(), diag::note_previous_definition);
3004 // a forward class declaration matching a typedef name of a class refers
3005 // to the underlying class. Just ignore the forward class with a warning
3006 // as this will force the intended behavior which is to lookup the
3008 if (isa<ObjCObjectType>(TDD->getUnderlyingType())) {
3009 Diag(AtClassLoc, diag::warn_forward_class_redefinition)
3011 Diag(PrevDecl->getLocation(), diag::note_previous_definition);
3017 // Create a declaration to describe this forward declaration.
3018 ObjCInterfaceDecl *PrevIDecl
3019 = dyn_cast_or_null<ObjCInterfaceDecl>(PrevDecl);
3021 IdentifierInfo *ClassName = IdentList[i];
3022 if (PrevIDecl && PrevIDecl->getIdentifier() != ClassName) {
3023 // A previous decl with a different name is because of
3024 // @compatibility_alias, for example:
3027 // @compatibility_alias OldImage NewImage;
3029 // A lookup for 'OldImage' will return the 'NewImage' decl.
3031 // In such a case use the real declaration name, instead of the alias one,
3032 // otherwise we will break IdentifierResolver and redecls-chain invariants.
3033 // FIXME: If necessary, add a bit to indicate that this ObjCInterfaceDecl
3034 // has been aliased.
3035 ClassName = PrevIDecl->getIdentifier();
3038 // If this forward declaration has type parameters, compare them with the
3039 // type parameters of the previous declaration.
3040 ObjCTypeParamList *TypeParams = TypeParamLists[i];
3041 if (PrevIDecl && TypeParams) {
3042 if (ObjCTypeParamList *PrevTypeParams = PrevIDecl->getTypeParamList()) {
3043 // Check for consistency with the previous declaration.
3044 if (checkTypeParamListConsistency(
3045 *this, PrevTypeParams, TypeParams,
3046 TypeParamListContext::ForwardDeclaration)) {
3047 TypeParams = nullptr;
3049 } else if (ObjCInterfaceDecl *Def = PrevIDecl->getDefinition()) {
3050 // The @interface does not have type parameters. Complain.
3051 Diag(IdentLocs[i], diag::err_objc_parameterized_forward_class)
3053 << TypeParams->getSourceRange();
3054 Diag(Def->getLocation(), diag::note_defined_here)
3057 TypeParams = nullptr;
3061 ObjCInterfaceDecl *IDecl
3062 = ObjCInterfaceDecl::Create(Context, CurContext, AtClassLoc,
3063 ClassName, TypeParams, PrevIDecl,
3065 IDecl->setAtEndRange(IdentLocs[i]);
3067 PushOnScopeChains(IDecl, TUScope);
3068 CheckObjCDeclScope(IDecl);
3069 DeclsInGroup.push_back(IDecl);
3072 return BuildDeclaratorGroup(DeclsInGroup);
3075 static bool tryMatchRecordTypes(ASTContext &Context,
3076 Sema::MethodMatchStrategy strategy,
3077 const Type *left, const Type *right);
3079 static bool matchTypes(ASTContext &Context, Sema::MethodMatchStrategy strategy,
3080 QualType leftQT, QualType rightQT) {
3082 Context.getCanonicalType(leftQT).getUnqualifiedType().getTypePtr();
3084 Context.getCanonicalType(rightQT).getUnqualifiedType().getTypePtr();
3086 if (left == right) return true;
3088 // If we're doing a strict match, the types have to match exactly.
3089 if (strategy == Sema::MMS_strict) return false;
3091 if (left->isIncompleteType() || right->isIncompleteType()) return false;
3093 // Otherwise, use this absurdly complicated algorithm to try to
3094 // validate the basic, low-level compatibility of the two types.
3096 // As a minimum, require the sizes and alignments to match.
3097 TypeInfo LeftTI = Context.getTypeInfo(left);
3098 TypeInfo RightTI = Context.getTypeInfo(right);
3099 if (LeftTI.Width != RightTI.Width)
3102 if (LeftTI.Align != RightTI.Align)
3105 // Consider all the kinds of non-dependent canonical types:
3106 // - functions and arrays aren't possible as return and parameter types
3108 // - vector types of equal size can be arbitrarily mixed
3109 if (isa<VectorType>(left)) return isa<VectorType>(right);
3110 if (isa<VectorType>(right)) return false;
3112 // - references should only match references of identical type
3113 // - structs, unions, and Objective-C objects must match more-or-less
3115 // - everything else should be a scalar
3116 if (!left->isScalarType() || !right->isScalarType())
3117 return tryMatchRecordTypes(Context, strategy, left, right);
3119 // Make scalars agree in kind, except count bools as chars, and group
3120 // all non-member pointers together.
3121 Type::ScalarTypeKind leftSK = left->getScalarTypeKind();
3122 Type::ScalarTypeKind rightSK = right->getScalarTypeKind();
3123 if (leftSK == Type::STK_Bool) leftSK = Type::STK_Integral;
3124 if (rightSK == Type::STK_Bool) rightSK = Type::STK_Integral;
3125 if (leftSK == Type::STK_CPointer || leftSK == Type::STK_BlockPointer)
3126 leftSK = Type::STK_ObjCObjectPointer;
3127 if (rightSK == Type::STK_CPointer || rightSK == Type::STK_BlockPointer)
3128 rightSK = Type::STK_ObjCObjectPointer;
3130 // Note that data member pointers and function member pointers don't
3131 // intermix because of the size differences.
3133 return (leftSK == rightSK);
3136 static bool tryMatchRecordTypes(ASTContext &Context,
3137 Sema::MethodMatchStrategy strategy,
3138 const Type *lt, const Type *rt) {
3139 assert(lt && rt && lt != rt);
3141 if (!isa<RecordType>(lt) || !isa<RecordType>(rt)) return false;
3142 RecordDecl *left = cast<RecordType>(lt)->getDecl();
3143 RecordDecl *right = cast<RecordType>(rt)->getDecl();
3145 // Require union-hood to match.
3146 if (left->isUnion() != right->isUnion()) return false;
3148 // Require an exact match if either is non-POD.
3149 if ((isa<CXXRecordDecl>(left) && !cast<CXXRecordDecl>(left)->isPOD()) ||
3150 (isa<CXXRecordDecl>(right) && !cast<CXXRecordDecl>(right)->isPOD()))
3153 // Require size and alignment to match.
3154 TypeInfo LeftTI = Context.getTypeInfo(lt);
3155 TypeInfo RightTI = Context.getTypeInfo(rt);
3156 if (LeftTI.Width != RightTI.Width)
3159 if (LeftTI.Align != RightTI.Align)
3162 // Require fields to match.
3163 RecordDecl::field_iterator li = left->field_begin(), le = left->field_end();
3164 RecordDecl::field_iterator ri = right->field_begin(), re = right->field_end();
3165 for (; li != le && ri != re; ++li, ++ri) {
3166 if (!matchTypes(Context, strategy, li->getType(), ri->getType()))
3169 return (li == le && ri == re);
3172 /// MatchTwoMethodDeclarations - Checks that two methods have matching type and
3173 /// returns true, or false, accordingly.
3174 /// TODO: Handle protocol list; such as id<p1,p2> in type comparisons
3175 bool Sema::MatchTwoMethodDeclarations(const ObjCMethodDecl *left,
3176 const ObjCMethodDecl *right,
3177 MethodMatchStrategy strategy) {
3178 if (!matchTypes(Context, strategy, left->getReturnType(),
3179 right->getReturnType()))
3182 // If either is hidden, it is not considered to match.
3183 if (left->isHidden() || right->isHidden())
3186 if (getLangOpts().ObjCAutoRefCount &&
3187 (left->hasAttr<NSReturnsRetainedAttr>()
3188 != right->hasAttr<NSReturnsRetainedAttr>() ||
3189 left->hasAttr<NSConsumesSelfAttr>()
3190 != right->hasAttr<NSConsumesSelfAttr>()))
3193 ObjCMethodDecl::param_const_iterator
3194 li = left->param_begin(), le = left->param_end(), ri = right->param_begin(),
3195 re = right->param_end();
3197 for (; li != le && ri != re; ++li, ++ri) {
3198 assert(ri != right->param_end() && "Param mismatch");
3199 const ParmVarDecl *lparm = *li, *rparm = *ri;
3201 if (!matchTypes(Context, strategy, lparm->getType(), rparm->getType()))
3204 if (getLangOpts().ObjCAutoRefCount &&
3205 lparm->hasAttr<NSConsumedAttr>() != rparm->hasAttr<NSConsumedAttr>())
3211 static bool isMethodContextSameForKindofLookup(ObjCMethodDecl *Method,
3212 ObjCMethodDecl *MethodInList) {
3213 auto *MethodProtocol = dyn_cast<ObjCProtocolDecl>(Method->getDeclContext());
3214 auto *MethodInListProtocol =
3215 dyn_cast<ObjCProtocolDecl>(MethodInList->getDeclContext());
3216 // If this method belongs to a protocol but the method in list does not, or
3217 // vice versa, we say the context is not the same.
3218 if ((MethodProtocol && !MethodInListProtocol) ||
3219 (!MethodProtocol && MethodInListProtocol))
3222 if (MethodProtocol && MethodInListProtocol)
3225 ObjCInterfaceDecl *MethodInterface = Method->getClassInterface();
3226 ObjCInterfaceDecl *MethodInListInterface =
3227 MethodInList->getClassInterface();
3228 return MethodInterface == MethodInListInterface;
3231 void Sema::addMethodToGlobalList(ObjCMethodList *List,
3232 ObjCMethodDecl *Method) {
3233 // Record at the head of the list whether there were 0, 1, or >= 2 methods
3234 // inside categories.
3235 if (ObjCCategoryDecl *CD =
3236 dyn_cast<ObjCCategoryDecl>(Method->getDeclContext()))
3237 if (!CD->IsClassExtension() && List->getBits() < 2)
3238 List->setBits(List->getBits() + 1);
3240 // If the list is empty, make it a singleton list.
3241 if (List->getMethod() == nullptr) {
3242 List->setMethod(Method);
3243 List->setNext(nullptr);
3247 // We've seen a method with this name, see if we have already seen this type
3249 ObjCMethodList *Previous = List;
3250 ObjCMethodList *ListWithSameDeclaration = nullptr;
3251 for (; List; Previous = List, List = List->getNext()) {
3252 // If we are building a module, keep all of the methods.
3253 if (getLangOpts().isCompilingModule())
3256 bool SameDeclaration = MatchTwoMethodDeclarations(Method,
3258 // Looking for method with a type bound requires the correct context exists.
3259 // We need to insert a method into the list if the context is different.
3260 // If the method's declaration matches the list
3261 // a> the method belongs to a different context: we need to insert it, in
3262 // order to emit the availability message, we need to prioritize over
3263 // availability among the methods with the same declaration.
3264 // b> the method belongs to the same context: there is no need to insert a
3266 // If the method's declaration does not match the list, we insert it to the
3268 if (!SameDeclaration ||
3269 !isMethodContextSameForKindofLookup(Method, List->getMethod())) {
3270 // Even if two method types do not match, we would like to say
3271 // there is more than one declaration so unavailability/deprecated
3272 // warning is not too noisy.
3273 if (!Method->isDefined())
3274 List->setHasMoreThanOneDecl(true);
3276 // For methods with the same declaration, the one that is deprecated
3277 // should be put in the front for better diagnostics.
3278 if (Method->isDeprecated() && SameDeclaration &&
3279 !ListWithSameDeclaration && !List->getMethod()->isDeprecated())
3280 ListWithSameDeclaration = List;
3282 if (Method->isUnavailable() && SameDeclaration &&
3283 !ListWithSameDeclaration &&
3284 List->getMethod()->getAvailability() < AR_Deprecated)
3285 ListWithSameDeclaration = List;
3289 ObjCMethodDecl *PrevObjCMethod = List->getMethod();
3291 // Propagate the 'defined' bit.
3292 if (Method->isDefined())
3293 PrevObjCMethod->setDefined(true);
3295 // Objective-C doesn't allow an @interface for a class after its
3296 // @implementation. So if Method is not defined and there already is
3297 // an entry for this type signature, Method has to be for a different
3298 // class than PrevObjCMethod.
3299 List->setHasMoreThanOneDecl(true);
3302 // If a method is deprecated, push it in the global pool.
3303 // This is used for better diagnostics.
3304 if (Method->isDeprecated()) {
3305 if (!PrevObjCMethod->isDeprecated())
3306 List->setMethod(Method);
3308 // If the new method is unavailable, push it into global pool
3309 // unless previous one is deprecated.
3310 if (Method->isUnavailable()) {
3311 if (PrevObjCMethod->getAvailability() < AR_Deprecated)
3312 List->setMethod(Method);
3318 // We have a new signature for an existing method - add it.
3319 // This is extremely rare. Only 1% of Cocoa selectors are "overloaded".
3320 ObjCMethodList *Mem = BumpAlloc.Allocate<ObjCMethodList>();
3322 // We insert it right before ListWithSameDeclaration.
3323 if (ListWithSameDeclaration) {
3324 auto *List = new (Mem) ObjCMethodList(*ListWithSameDeclaration);
3325 // FIXME: should we clear the other bits in ListWithSameDeclaration?
3326 ListWithSameDeclaration->setMethod(Method);
3327 ListWithSameDeclaration->setNext(List);
3331 Previous->setNext(new (Mem) ObjCMethodList(Method));
3334 /// \brief Read the contents of the method pool for a given selector from
3335 /// external storage.
3336 void Sema::ReadMethodPool(Selector Sel) {
3337 assert(ExternalSource && "We need an external AST source");
3338 ExternalSource->ReadMethodPool(Sel);
3341 void Sema::updateOutOfDateSelector(Selector Sel) {
3342 if (!ExternalSource)
3344 ExternalSource->updateOutOfDateSelector(Sel);
3347 void Sema::AddMethodToGlobalPool(ObjCMethodDecl *Method, bool impl,
3349 // Ignore methods of invalid containers.
3350 if (cast<Decl>(Method->getDeclContext())->isInvalidDecl())
3354 ReadMethodPool(Method->getSelector());
3356 GlobalMethodPool::iterator Pos = MethodPool.find(Method->getSelector());
3357 if (Pos == MethodPool.end())
3358 Pos = MethodPool.insert(std::make_pair(Method->getSelector(),
3359 GlobalMethods())).first;
3361 Method->setDefined(impl);
3363 ObjCMethodList &Entry = instance ? Pos->second.first : Pos->second.second;
3364 addMethodToGlobalList(&Entry, Method);
3367 /// Determines if this is an "acceptable" loose mismatch in the global
3368 /// method pool. This exists mostly as a hack to get around certain
3369 /// global mismatches which we can't afford to make warnings / errors.
3370 /// Really, what we want is a way to take a method out of the global
3372 static bool isAcceptableMethodMismatch(ObjCMethodDecl *chosen,
3373 ObjCMethodDecl *other) {
3374 if (!chosen->isInstanceMethod())
3377 Selector sel = chosen->getSelector();
3378 if (!sel.isUnarySelector() || sel.getNameForSlot(0) != "length")
3381 // Don't complain about mismatches for -length if the method we
3382 // chose has an integral result type.
3383 return (chosen->getReturnType()->isIntegerType());
3386 /// Return true if the given method is wthin the type bound.
3387 static bool FilterMethodsByTypeBound(ObjCMethodDecl *Method,
3388 const ObjCObjectType *TypeBound) {
3392 if (TypeBound->isObjCId())
3393 // FIXME: should we handle the case of bounding to id<A, B> differently?
3396 auto *BoundInterface = TypeBound->getInterface();
3397 assert(BoundInterface && "unexpected object type!");
3399 // Check if the Method belongs to a protocol. We should allow any method
3400 // defined in any protocol, because any subclass could adopt the protocol.
3401 auto *MethodProtocol = dyn_cast<ObjCProtocolDecl>(Method->getDeclContext());
3402 if (MethodProtocol) {
3406 // If the Method belongs to a class, check if it belongs to the class
3407 // hierarchy of the class bound.
3408 if (ObjCInterfaceDecl *MethodInterface = Method->getClassInterface()) {
3409 // We allow methods declared within classes that are part of the hierarchy
3410 // of the class bound (superclass of, subclass of, or the same as the class
3412 return MethodInterface == BoundInterface ||
3413 MethodInterface->isSuperClassOf(BoundInterface) ||
3414 BoundInterface->isSuperClassOf(MethodInterface);
3416 llvm_unreachable("unknow method context");
3419 /// We first select the type of the method: Instance or Factory, then collect
3420 /// all methods with that type.
3421 bool Sema::CollectMultipleMethodsInGlobalPool(
3422 Selector Sel, SmallVectorImpl<ObjCMethodDecl *> &Methods,
3423 bool InstanceFirst, bool CheckTheOther,
3424 const ObjCObjectType *TypeBound) {
3426 ReadMethodPool(Sel);
3428 GlobalMethodPool::iterator Pos = MethodPool.find(Sel);
3429 if (Pos == MethodPool.end())
3432 // Gather the non-hidden methods.
3433 ObjCMethodList &MethList = InstanceFirst ? Pos->second.first :
3435 for (ObjCMethodList *M = &MethList; M; M = M->getNext())
3436 if (M->getMethod() && !M->getMethod()->isHidden()) {
3437 if (FilterMethodsByTypeBound(M->getMethod(), TypeBound))
3438 Methods.push_back(M->getMethod());
3441 // Return if we find any method with the desired kind.
3442 if (!Methods.empty())
3443 return Methods.size() > 1;
3448 // Gather the other kind.
3449 ObjCMethodList &MethList2 = InstanceFirst ? Pos->second.second :
3451 for (ObjCMethodList *M = &MethList2; M; M = M->getNext())
3452 if (M->getMethod() && !M->getMethod()->isHidden()) {
3453 if (FilterMethodsByTypeBound(M->getMethod(), TypeBound))
3454 Methods.push_back(M->getMethod());
3457 return Methods.size() > 1;
3460 bool Sema::AreMultipleMethodsInGlobalPool(
3461 Selector Sel, ObjCMethodDecl *BestMethod, SourceRange R,
3462 bool receiverIdOrClass, SmallVectorImpl<ObjCMethodDecl *> &Methods) {
3463 // Diagnose finding more than one method in global pool.
3464 SmallVector<ObjCMethodDecl *, 4> FilteredMethods;
3465 FilteredMethods.push_back(BestMethod);
3467 for (auto *M : Methods)
3468 if (M != BestMethod && !M->hasAttr<UnavailableAttr>())
3469 FilteredMethods.push_back(M);
3471 if (FilteredMethods.size() > 1)
3472 DiagnoseMultipleMethodInGlobalPool(FilteredMethods, Sel, R,
3475 GlobalMethodPool::iterator Pos = MethodPool.find(Sel);
3476 // Test for no method in the pool which should not trigger any warning by
3478 if (Pos == MethodPool.end())
3480 ObjCMethodList &MethList =
3481 BestMethod->isInstanceMethod() ? Pos->second.first : Pos->second.second;
3482 return MethList.hasMoreThanOneDecl();
3485 ObjCMethodDecl *Sema::LookupMethodInGlobalPool(Selector Sel, SourceRange R,
3486 bool receiverIdOrClass,
3489 ReadMethodPool(Sel);
3491 GlobalMethodPool::iterator Pos = MethodPool.find(Sel);
3492 if (Pos == MethodPool.end())
3495 // Gather the non-hidden methods.
3496 ObjCMethodList &MethList = instance ? Pos->second.first : Pos->second.second;
3497 SmallVector<ObjCMethodDecl *, 4> Methods;
3498 for (ObjCMethodList *M = &MethList; M; M = M->getNext()) {
3499 if (M->getMethod() && !M->getMethod()->isHidden())
3500 return M->getMethod();
3505 void Sema::DiagnoseMultipleMethodInGlobalPool(SmallVectorImpl<ObjCMethodDecl*> &Methods,
3506 Selector Sel, SourceRange R,
3507 bool receiverIdOrClass) {
3508 // We found multiple methods, so we may have to complain.
3509 bool issueDiagnostic = false, issueError = false;
3511 // We support a warning which complains about *any* difference in
3512 // method signature.
3513 bool strictSelectorMatch =
3514 receiverIdOrClass &&
3515 !Diags.isIgnored(diag::warn_strict_multiple_method_decl, R.getBegin());
3516 if (strictSelectorMatch) {
3517 for (unsigned I = 1, N = Methods.size(); I != N; ++I) {
3518 if (!MatchTwoMethodDeclarations(Methods[0], Methods[I], MMS_strict)) {
3519 issueDiagnostic = true;
3525 // If we didn't see any strict differences, we won't see any loose
3526 // differences. In ARC, however, we also need to check for loose
3527 // mismatches, because most of them are errors.
3528 if (!strictSelectorMatch ||
3529 (issueDiagnostic && getLangOpts().ObjCAutoRefCount))
3530 for (unsigned I = 1, N = Methods.size(); I != N; ++I) {
3531 // This checks if the methods differ in type mismatch.
3532 if (!MatchTwoMethodDeclarations(Methods[0], Methods[I], MMS_loose) &&
3533 !isAcceptableMethodMismatch(Methods[0], Methods[I])) {
3534 issueDiagnostic = true;
3535 if (getLangOpts().ObjCAutoRefCount)
3541 if (issueDiagnostic) {
3543 Diag(R.getBegin(), diag::err_arc_multiple_method_decl) << Sel << R;
3544 else if (strictSelectorMatch)
3545 Diag(R.getBegin(), diag::warn_strict_multiple_method_decl) << Sel << R;
3547 Diag(R.getBegin(), diag::warn_multiple_method_decl) << Sel << R;
3549 Diag(Methods[0]->getLocStart(),
3550 issueError ? diag::note_possibility : diag::note_using)
3551 << Methods[0]->getSourceRange();
3552 for (unsigned I = 1, N = Methods.size(); I != N; ++I) {
3553 Diag(Methods[I]->getLocStart(), diag::note_also_found)
3554 << Methods[I]->getSourceRange();
3559 ObjCMethodDecl *Sema::LookupImplementedMethodInGlobalPool(Selector Sel) {
3560 GlobalMethodPool::iterator Pos = MethodPool.find(Sel);
3561 if (Pos == MethodPool.end())
3564 GlobalMethods &Methods = Pos->second;
3565 for (const ObjCMethodList *Method = &Methods.first; Method;
3566 Method = Method->getNext())
3567 if (Method->getMethod() &&
3568 (Method->getMethod()->isDefined() ||
3569 Method->getMethod()->isPropertyAccessor()))
3570 return Method->getMethod();
3572 for (const ObjCMethodList *Method = &Methods.second; Method;
3573 Method = Method->getNext())
3574 if (Method->getMethod() &&
3575 (Method->getMethod()->isDefined() ||
3576 Method->getMethod()->isPropertyAccessor()))
3577 return Method->getMethod();
3582 HelperSelectorsForTypoCorrection(
3583 SmallVectorImpl<const ObjCMethodDecl *> &BestMethod,
3584 StringRef Typo, const ObjCMethodDecl * Method) {
3585 const unsigned MaxEditDistance = 1;
3586 unsigned BestEditDistance = MaxEditDistance + 1;
3587 std::string MethodName = Method->getSelector().getAsString();
3589 unsigned MinPossibleEditDistance = abs((int)MethodName.size() - (int)Typo.size());
3590 if (MinPossibleEditDistance > 0 &&
3591 Typo.size() / MinPossibleEditDistance < 1)
3593 unsigned EditDistance = Typo.edit_distance(MethodName, true, MaxEditDistance);
3594 if (EditDistance > MaxEditDistance)
3596 if (EditDistance == BestEditDistance)
3597 BestMethod.push_back(Method);
3598 else if (EditDistance < BestEditDistance) {
3600 BestMethod.push_back(Method);
3604 static bool HelperIsMethodInObjCType(Sema &S, Selector Sel,
3605 QualType ObjectType) {
3606 if (ObjectType.isNull())
3608 if (S.LookupMethodInObjectType(Sel, ObjectType, true/*Instance method*/))
3610 return S.LookupMethodInObjectType(Sel, ObjectType, false/*Class method*/) !=
3614 const ObjCMethodDecl *
3615 Sema::SelectorsForTypoCorrection(Selector Sel,
3616 QualType ObjectType) {
3617 unsigned NumArgs = Sel.getNumArgs();
3618 SmallVector<const ObjCMethodDecl *, 8> Methods;
3619 bool ObjectIsId = true, ObjectIsClass = true;
3620 if (ObjectType.isNull())
3621 ObjectIsId = ObjectIsClass = false;
3622 else if (!ObjectType->isObjCObjectPointerType())
3624 else if (const ObjCObjectPointerType *ObjCPtr =
3625 ObjectType->getAsObjCInterfacePointerType()) {
3626 ObjectType = QualType(ObjCPtr->getInterfaceType(), 0);
3627 ObjectIsId = ObjectIsClass = false;
3629 else if (ObjectType->isObjCIdType() || ObjectType->isObjCQualifiedIdType())
3630 ObjectIsClass = false;
3631 else if (ObjectType->isObjCClassType() || ObjectType->isObjCQualifiedClassType())
3636 for (GlobalMethodPool::iterator b = MethodPool.begin(),
3637 e = MethodPool.end(); b != e; b++) {
3639 for (ObjCMethodList *M = &b->second.first; M; M=M->getNext())
3640 if (M->getMethod() &&
3641 (M->getMethod()->getSelector().getNumArgs() == NumArgs) &&
3642 (M->getMethod()->getSelector() != Sel)) {
3644 Methods.push_back(M->getMethod());
3645 else if (!ObjectIsClass &&
3646 HelperIsMethodInObjCType(*this, M->getMethod()->getSelector(),
3648 Methods.push_back(M->getMethod());
3651 for (ObjCMethodList *M = &b->second.second; M; M=M->getNext())
3652 if (M->getMethod() &&
3653 (M->getMethod()->getSelector().getNumArgs() == NumArgs) &&
3654 (M->getMethod()->getSelector() != Sel)) {
3656 Methods.push_back(M->getMethod());
3657 else if (!ObjectIsId &&
3658 HelperIsMethodInObjCType(*this, M->getMethod()->getSelector(),
3660 Methods.push_back(M->getMethod());
3664 SmallVector<const ObjCMethodDecl *, 8> SelectedMethods;
3665 for (unsigned i = 0, e = Methods.size(); i < e; i++) {
3666 HelperSelectorsForTypoCorrection(SelectedMethods,
3667 Sel.getAsString(), Methods[i]);
3669 return (SelectedMethods.size() == 1) ? SelectedMethods[0] : nullptr;
3672 /// DiagnoseDuplicateIvars -
3673 /// Check for duplicate ivars in the entire class at the start of
3674 /// \@implementation. This becomes necesssary because class extension can
3675 /// add ivars to a class in random order which will not be known until
3676 /// class's \@implementation is seen.
3677 void Sema::DiagnoseDuplicateIvars(ObjCInterfaceDecl *ID,
3678 ObjCInterfaceDecl *SID) {
3679 for (auto *Ivar : ID->ivars()) {
3680 if (Ivar->isInvalidDecl())
3682 if (IdentifierInfo *II = Ivar->getIdentifier()) {
3683 ObjCIvarDecl* prevIvar = SID->lookupInstanceVariable(II);
3685 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II;
3686 Diag(prevIvar->getLocation(), diag::note_previous_declaration);
3687 Ivar->setInvalidDecl();
3693 /// Diagnose attempts to define ARC-__weak ivars when __weak is disabled.
3694 static void DiagnoseWeakIvars(Sema &S, ObjCImplementationDecl *ID) {
3695 if (S.getLangOpts().ObjCWeak) return;
3697 for (auto ivar = ID->getClassInterface()->all_declared_ivar_begin();
3698 ivar; ivar = ivar->getNextIvar()) {
3699 if (ivar->isInvalidDecl()) continue;
3700 if (ivar->getType().getObjCLifetime() == Qualifiers::OCL_Weak) {
3701 if (S.getLangOpts().ObjCWeakRuntime) {
3702 S.Diag(ivar->getLocation(), diag::err_arc_weak_disabled);
3704 S.Diag(ivar->getLocation(), diag::err_arc_weak_no_runtime);
3710 Sema::ObjCContainerKind Sema::getObjCContainerKind() const {
3711 switch (CurContext->getDeclKind()) {
3712 case Decl::ObjCInterface:
3713 return Sema::OCK_Interface;
3714 case Decl::ObjCProtocol:
3715 return Sema::OCK_Protocol;
3716 case Decl::ObjCCategory:
3717 if (cast<ObjCCategoryDecl>(CurContext)->IsClassExtension())
3718 return Sema::OCK_ClassExtension;
3719 return Sema::OCK_Category;
3720 case Decl::ObjCImplementation:
3721 return Sema::OCK_Implementation;
3722 case Decl::ObjCCategoryImpl:
3723 return Sema::OCK_CategoryImplementation;
3726 return Sema::OCK_None;
3730 // Note: For class/category implementations, allMethods is always null.
3731 Decl *Sema::ActOnAtEnd(Scope *S, SourceRange AtEnd, ArrayRef<Decl *> allMethods,
3732 ArrayRef<DeclGroupPtrTy> allTUVars) {
3733 if (getObjCContainerKind() == Sema::OCK_None)
3736 assert(AtEnd.isValid() && "Invalid location for '@end'");
3738 ObjCContainerDecl *OCD = dyn_cast<ObjCContainerDecl>(CurContext);
3739 Decl *ClassDecl = cast<Decl>(OCD);
3741 bool isInterfaceDeclKind =
3742 isa<ObjCInterfaceDecl>(ClassDecl) || isa<ObjCCategoryDecl>(ClassDecl)
3743 || isa<ObjCProtocolDecl>(ClassDecl);
3744 bool checkIdenticalMethods = isa<ObjCImplementationDecl>(ClassDecl);
3746 // FIXME: Remove these and use the ObjCContainerDecl/DeclContext.
3747 llvm::DenseMap<Selector, const ObjCMethodDecl*> InsMap;
3748 llvm::DenseMap<Selector, const ObjCMethodDecl*> ClsMap;
3750 for (unsigned i = 0, e = allMethods.size(); i != e; i++ ) {
3751 ObjCMethodDecl *Method =
3752 cast_or_null<ObjCMethodDecl>(allMethods[i]);
3754 if (!Method) continue; // Already issued a diagnostic.
3755 if (Method->isInstanceMethod()) {
3756 /// Check for instance method of the same name with incompatible types
3757 const ObjCMethodDecl *&PrevMethod = InsMap[Method->getSelector()];
3758 bool match = PrevMethod ? MatchTwoMethodDeclarations(Method, PrevMethod)
3760 if ((isInterfaceDeclKind && PrevMethod && !match)
3761 || (checkIdenticalMethods && match)) {
3762 Diag(Method->getLocation(), diag::err_duplicate_method_decl)
3763 << Method->getDeclName();
3764 Diag(PrevMethod->getLocation(), diag::note_previous_declaration);
3765 Method->setInvalidDecl();
3768 Method->setAsRedeclaration(PrevMethod);
3769 if (!Context.getSourceManager().isInSystemHeader(
3770 Method->getLocation()))
3771 Diag(Method->getLocation(), diag::warn_duplicate_method_decl)
3772 << Method->getDeclName();
3773 Diag(PrevMethod->getLocation(), diag::note_previous_declaration);
3775 InsMap[Method->getSelector()] = Method;
3776 /// The following allows us to typecheck messages to "id".
3777 AddInstanceMethodToGlobalPool(Method);
3780 /// Check for class method of the same name with incompatible types
3781 const ObjCMethodDecl *&PrevMethod = ClsMap[Method->getSelector()];
3782 bool match = PrevMethod ? MatchTwoMethodDeclarations(Method, PrevMethod)
3784 if ((isInterfaceDeclKind && PrevMethod && !match)
3785 || (checkIdenticalMethods && match)) {
3786 Diag(Method->getLocation(), diag::err_duplicate_method_decl)
3787 << Method->getDeclName();
3788 Diag(PrevMethod->getLocation(), diag::note_previous_declaration);
3789 Method->setInvalidDecl();
3792 Method->setAsRedeclaration(PrevMethod);
3793 if (!Context.getSourceManager().isInSystemHeader(
3794 Method->getLocation()))
3795 Diag(Method->getLocation(), diag::warn_duplicate_method_decl)
3796 << Method->getDeclName();
3797 Diag(PrevMethod->getLocation(), diag::note_previous_declaration);
3799 ClsMap[Method->getSelector()] = Method;
3800 AddFactoryMethodToGlobalPool(Method);
3804 if (isa<ObjCInterfaceDecl>(ClassDecl)) {
3805 // Nothing to do here.
3806 } else if (ObjCCategoryDecl *C = dyn_cast<ObjCCategoryDecl>(ClassDecl)) {
3807 // Categories are used to extend the class by declaring new methods.
3808 // By the same token, they are also used to add new properties. No
3809 // need to compare the added property to those in the class.
3811 if (C->IsClassExtension()) {
3812 ObjCInterfaceDecl *CCPrimary = C->getClassInterface();
3813 DiagnoseClassExtensionDupMethods(C, CCPrimary);
3816 if (ObjCContainerDecl *CDecl = dyn_cast<ObjCContainerDecl>(ClassDecl)) {
3817 if (CDecl->getIdentifier())
3818 // ProcessPropertyDecl is responsible for diagnosing conflicts with any
3819 // user-defined setter/getter. It also synthesizes setter/getter methods
3820 // and adds them to the DeclContext and global method pools.
3821 for (auto *I : CDecl->properties())
3822 ProcessPropertyDecl(I);
3823 CDecl->setAtEndRange(AtEnd);
3825 if (ObjCImplementationDecl *IC=dyn_cast<ObjCImplementationDecl>(ClassDecl)) {
3826 IC->setAtEndRange(AtEnd);
3827 if (ObjCInterfaceDecl* IDecl = IC->getClassInterface()) {
3828 // Any property declared in a class extension might have user
3829 // declared setter or getter in current class extension or one
3830 // of the other class extensions. Mark them as synthesized as
3831 // property will be synthesized when property with same name is
3832 // seen in the @implementation.
3833 for (const auto *Ext : IDecl->visible_extensions()) {
3834 for (const auto *Property : Ext->instance_properties()) {
3835 // Skip over properties declared @dynamic
3836 if (const ObjCPropertyImplDecl *PIDecl
3837 = IC->FindPropertyImplDecl(Property->getIdentifier(),
3838 Property->getQueryKind()))
3839 if (PIDecl->getPropertyImplementation()
3840 == ObjCPropertyImplDecl::Dynamic)
3843 for (const auto *Ext : IDecl->visible_extensions()) {
3844 if (ObjCMethodDecl *GetterMethod
3845 = Ext->getInstanceMethod(Property->getGetterName()))
3846 GetterMethod->setPropertyAccessor(true);
3847 if (!Property->isReadOnly())
3848 if (ObjCMethodDecl *SetterMethod
3849 = Ext->getInstanceMethod(Property->getSetterName()))
3850 SetterMethod->setPropertyAccessor(true);
3854 ImplMethodsVsClassMethods(S, IC, IDecl);
3855 AtomicPropertySetterGetterRules(IC, IDecl);
3856 DiagnoseOwningPropertyGetterSynthesis(IC);
3857 DiagnoseUnusedBackingIvarInAccessor(S, IC);
3858 if (IDecl->hasDesignatedInitializers())
3859 DiagnoseMissingDesignatedInitOverrides(IC, IDecl);
3860 DiagnoseWeakIvars(*this, IC);
3862 bool HasRootClassAttr = IDecl->hasAttr<ObjCRootClassAttr>();
3863 if (IDecl->getSuperClass() == nullptr) {
3864 // This class has no superclass, so check that it has been marked with
3865 // __attribute((objc_root_class)).
3866 if (!HasRootClassAttr) {
3867 SourceLocation DeclLoc(IDecl->getLocation());
3868 SourceLocation SuperClassLoc(getLocForEndOfToken(DeclLoc));
3869 Diag(DeclLoc, diag::warn_objc_root_class_missing)
3870 << IDecl->getIdentifier();
3871 // See if NSObject is in the current scope, and if it is, suggest
3872 // adding " : NSObject " to the class declaration.
3873 NamedDecl *IF = LookupSingleName(TUScope,
3874 NSAPIObj->getNSClassId(NSAPI::ClassId_NSObject),
3875 DeclLoc, LookupOrdinaryName);
3876 ObjCInterfaceDecl *NSObjectDecl = dyn_cast_or_null<ObjCInterfaceDecl>(IF);
3877 if (NSObjectDecl && NSObjectDecl->getDefinition()) {
3878 Diag(SuperClassLoc, diag::note_objc_needs_superclass)
3879 << FixItHint::CreateInsertion(SuperClassLoc, " : NSObject ");
3881 Diag(SuperClassLoc, diag::note_objc_needs_superclass);
3884 } else if (HasRootClassAttr) {
3885 // Complain that only root classes may have this attribute.
3886 Diag(IDecl->getLocation(), diag::err_objc_root_class_subclass);
3889 if (const ObjCInterfaceDecl *Super = IDecl->getSuperClass()) {
3890 // An interface can subclass another interface with a
3891 // objc_subclassing_restricted attribute when it has that attribute as
3892 // well (because of interfaces imported from Swift). Therefore we have
3893 // to check if we can subclass in the implementation as well.
3894 if (IDecl->hasAttr<ObjCSubclassingRestrictedAttr>() &&
3895 Super->hasAttr<ObjCSubclassingRestrictedAttr>()) {
3896 Diag(IC->getLocation(), diag::err_restricted_superclass_mismatch);
3897 Diag(Super->getLocation(), diag::note_class_declared);
3901 if (LangOpts.ObjCRuntime.isNonFragile()) {
3902 while (IDecl->getSuperClass()) {
3903 DiagnoseDuplicateIvars(IDecl, IDecl->getSuperClass());
3904 IDecl = IDecl->getSuperClass();
3908 SetIvarInitializers(IC);
3909 } else if (ObjCCategoryImplDecl* CatImplClass =
3910 dyn_cast<ObjCCategoryImplDecl>(ClassDecl)) {
3911 CatImplClass->setAtEndRange(AtEnd);
3913 // Find category interface decl and then check that all methods declared
3914 // in this interface are implemented in the category @implementation.
3915 if (ObjCInterfaceDecl* IDecl = CatImplClass->getClassInterface()) {
3916 if (ObjCCategoryDecl *Cat
3917 = IDecl->FindCategoryDeclaration(CatImplClass->getIdentifier())) {
3918 ImplMethodsVsClassMethods(S, CatImplClass, Cat);
3921 } else if (const auto *IntfDecl = dyn_cast<ObjCInterfaceDecl>(ClassDecl)) {
3922 if (const ObjCInterfaceDecl *Super = IntfDecl->getSuperClass()) {
3923 if (!IntfDecl->hasAttr<ObjCSubclassingRestrictedAttr>() &&
3924 Super->hasAttr<ObjCSubclassingRestrictedAttr>()) {
3925 Diag(IntfDecl->getLocation(), diag::err_restricted_superclass_mismatch);
3926 Diag(Super->getLocation(), diag::note_class_declared);
3930 if (isInterfaceDeclKind) {
3931 // Reject invalid vardecls.
3932 for (unsigned i = 0, e = allTUVars.size(); i != e; i++) {
3933 DeclGroupRef DG = allTUVars[i].get();
3934 for (DeclGroupRef::iterator I = DG.begin(), E = DG.end(); I != E; ++I)
3935 if (VarDecl *VDecl = dyn_cast<VarDecl>(*I)) {
3936 if (!VDecl->hasExternalStorage())
3937 Diag(VDecl->getLocation(), diag::err_objc_var_decl_inclass);
3941 ActOnObjCContainerFinishDefinition();
3943 for (unsigned i = 0, e = allTUVars.size(); i != e; i++) {
3944 DeclGroupRef DG = allTUVars[i].get();
3945 for (DeclGroupRef::iterator I = DG.begin(), E = DG.end(); I != E; ++I)
3946 (*I)->setTopLevelDeclInObjCContainer();
3947 Consumer.HandleTopLevelDeclInObjCContainer(DG);
3950 ActOnDocumentableDecl(ClassDecl);
3954 /// CvtQTToAstBitMask - utility routine to produce an AST bitmask for
3955 /// objective-c's type qualifier from the parser version of the same info.
3956 static Decl::ObjCDeclQualifier
3957 CvtQTToAstBitMask(ObjCDeclSpec::ObjCDeclQualifier PQTVal) {
3958 return (Decl::ObjCDeclQualifier) (unsigned) PQTVal;
3961 /// \brief Check whether the declared result type of the given Objective-C
3962 /// method declaration is compatible with the method's class.
3964 static Sema::ResultTypeCompatibilityKind
3965 CheckRelatedResultTypeCompatibility(Sema &S, ObjCMethodDecl *Method,
3966 ObjCInterfaceDecl *CurrentClass) {
3967 QualType ResultType = Method->getReturnType();
3969 // If an Objective-C method inherits its related result type, then its
3970 // declared result type must be compatible with its own class type. The
3971 // declared result type is compatible if:
3972 if (const ObjCObjectPointerType *ResultObjectType
3973 = ResultType->getAs<ObjCObjectPointerType>()) {
3974 // - it is id or qualified id, or
3975 if (ResultObjectType->isObjCIdType() ||
3976 ResultObjectType->isObjCQualifiedIdType())
3977 return Sema::RTC_Compatible;
3980 if (ObjCInterfaceDecl *ResultClass
3981 = ResultObjectType->getInterfaceDecl()) {
3982 // - it is the same as the method's class type, or
3983 if (declaresSameEntity(CurrentClass, ResultClass))
3984 return Sema::RTC_Compatible;
3986 // - it is a superclass of the method's class type
3987 if (ResultClass->isSuperClassOf(CurrentClass))
3988 return Sema::RTC_Compatible;
3991 // Any Objective-C pointer type might be acceptable for a protocol
3992 // method; we just don't know.
3993 return Sema::RTC_Unknown;
3997 return Sema::RTC_Incompatible;
4001 /// A helper class for searching for methods which a particular method
4003 class OverrideSearch {
4006 ObjCMethodDecl *Method;
4007 llvm::SmallPtrSet<ObjCMethodDecl*, 4> Overridden;
4011 OverrideSearch(Sema &S, ObjCMethodDecl *method) : S(S), Method(method) {
4012 Selector selector = method->getSelector();
4014 // Bypass this search if we've never seen an instance/class method
4015 // with this selector before.
4016 Sema::GlobalMethodPool::iterator it = S.MethodPool.find(selector);
4017 if (it == S.MethodPool.end()) {
4018 if (!S.getExternalSource()) return;
4019 S.ReadMethodPool(selector);
4021 it = S.MethodPool.find(selector);
4022 if (it == S.MethodPool.end())
4025 ObjCMethodList &list =
4026 method->isInstanceMethod() ? it->second.first : it->second.second;
4027 if (!list.getMethod()) return;
4029 ObjCContainerDecl *container
4030 = cast<ObjCContainerDecl>(method->getDeclContext());
4032 // Prevent the search from reaching this container again. This is
4033 // important with categories, which override methods from the
4034 // interface and each other.
4035 if (ObjCCategoryDecl *Category = dyn_cast<ObjCCategoryDecl>(container)) {
4036 searchFromContainer(container);
4037 if (ObjCInterfaceDecl *Interface = Category->getClassInterface())
4038 searchFromContainer(Interface);
4040 searchFromContainer(container);
4044 typedef llvm::SmallPtrSetImpl<ObjCMethodDecl*>::iterator iterator;
4045 iterator begin() const { return Overridden.begin(); }
4046 iterator end() const { return Overridden.end(); }
4049 void searchFromContainer(ObjCContainerDecl *container) {
4050 if (container->isInvalidDecl()) return;
4052 switch (container->getDeclKind()) {
4053 #define OBJCCONTAINER(type, base) \
4055 searchFrom(cast<type##Decl>(container)); \
4057 #define ABSTRACT_DECL(expansion)
4058 #define DECL(type, base) \
4060 #include "clang/AST/DeclNodes.inc"
4061 llvm_unreachable("not an ObjC container!");
4065 void searchFrom(ObjCProtocolDecl *protocol) {
4066 if (!protocol->hasDefinition())
4069 // A method in a protocol declaration overrides declarations from
4070 // referenced ("parent") protocols.
4071 search(protocol->getReferencedProtocols());
4074 void searchFrom(ObjCCategoryDecl *category) {
4075 // A method in a category declaration overrides declarations from
4076 // the main class and from protocols the category references.
4077 // The main class is handled in the constructor.
4078 search(category->getReferencedProtocols());
4081 void searchFrom(ObjCCategoryImplDecl *impl) {
4082 // A method in a category definition that has a category
4083 // declaration overrides declarations from the category
4085 if (ObjCCategoryDecl *category = impl->getCategoryDecl()) {
4087 if (ObjCInterfaceDecl *Interface = category->getClassInterface())
4090 // Otherwise it overrides declarations from the class.
4091 } else if (ObjCInterfaceDecl *Interface = impl->getClassInterface()) {
4096 void searchFrom(ObjCInterfaceDecl *iface) {
4097 // A method in a class declaration overrides declarations from
4098 if (!iface->hasDefinition())
4102 for (auto *Cat : iface->known_categories())
4105 // - the super class, and
4106 if (ObjCInterfaceDecl *super = iface->getSuperClass())
4109 // - any referenced protocols.
4110 search(iface->getReferencedProtocols());
4113 void searchFrom(ObjCImplementationDecl *impl) {
4114 // A method in a class implementation overrides declarations from
4115 // the class interface.
4116 if (ObjCInterfaceDecl *Interface = impl->getClassInterface())
4120 void search(const ObjCProtocolList &protocols) {
4121 for (ObjCProtocolList::iterator i = protocols.begin(), e = protocols.end();
4126 void search(ObjCContainerDecl *container) {
4127 // Check for a method in this container which matches this selector.
4128 ObjCMethodDecl *meth = container->getMethod(Method->getSelector(),
4129 Method->isInstanceMethod(),
4130 /*AllowHidden=*/true);
4132 // If we find one, record it and bail out.
4134 Overridden.insert(meth);
4138 // Otherwise, search for methods that a hypothetical method here
4139 // would have overridden.
4141 // Note that we're now in a recursive case.
4144 searchFromContainer(container);
4147 } // end anonymous namespace
4149 void Sema::CheckObjCMethodOverrides(ObjCMethodDecl *ObjCMethod,
4150 ObjCInterfaceDecl *CurrentClass,
4151 ResultTypeCompatibilityKind RTC) {
4152 // Search for overridden methods and merge information down from them.
4153 OverrideSearch overrides(*this, ObjCMethod);
4154 // Keep track if the method overrides any method in the class's base classes,
4155 // its protocols, or its categories' protocols; we will keep that info
4156 // in the ObjCMethodDecl.
4157 // For this info, a method in an implementation is not considered as
4158 // overriding the same method in the interface or its categories.
4159 bool hasOverriddenMethodsInBaseOrProtocol = false;
4160 for (OverrideSearch::iterator
4161 i = overrides.begin(), e = overrides.end(); i != e; ++i) {
4162 ObjCMethodDecl *overridden = *i;
4164 if (!hasOverriddenMethodsInBaseOrProtocol) {
4165 if (isa<ObjCProtocolDecl>(overridden->getDeclContext()) ||
4166 CurrentClass != overridden->getClassInterface() ||
4167 overridden->isOverriding()) {
4168 hasOverriddenMethodsInBaseOrProtocol = true;
4170 } else if (isa<ObjCImplDecl>(ObjCMethod->getDeclContext())) {
4171 // OverrideSearch will return as "overridden" the same method in the
4172 // interface. For hasOverriddenMethodsInBaseOrProtocol, we need to
4173 // check whether a category of a base class introduced a method with the
4174 // same selector, after the interface method declaration.
4175 // To avoid unnecessary lookups in the majority of cases, we use the
4176 // extra info bits in GlobalMethodPool to check whether there were any
4177 // category methods with this selector.
4178 GlobalMethodPool::iterator It =
4179 MethodPool.find(ObjCMethod->getSelector());
4180 if (It != MethodPool.end()) {
4181 ObjCMethodList &List =
4182 ObjCMethod->isInstanceMethod()? It->second.first: It->second.second;
4183 unsigned CategCount = List.getBits();
4184 if (CategCount > 0) {
4185 // If the method is in a category we'll do lookup if there were at
4186 // least 2 category methods recorded, otherwise only one will do.
4187 if (CategCount > 1 ||
4188 !isa<ObjCCategoryImplDecl>(overridden->getDeclContext())) {
4189 OverrideSearch overrides(*this, overridden);
4190 for (OverrideSearch::iterator
4191 OI= overrides.begin(), OE= overrides.end(); OI!=OE; ++OI) {
4192 ObjCMethodDecl *SuperOverridden = *OI;
4193 if (isa<ObjCProtocolDecl>(SuperOverridden->getDeclContext()) ||
4194 CurrentClass != SuperOverridden->getClassInterface()) {
4195 hasOverriddenMethodsInBaseOrProtocol = true;
4196 overridden->setOverriding(true);
4206 // Propagate down the 'related result type' bit from overridden methods.
4207 if (RTC != Sema::RTC_Incompatible && overridden->hasRelatedResultType())
4208 ObjCMethod->SetRelatedResultType();
4210 // Then merge the declarations.
4211 mergeObjCMethodDecls(ObjCMethod, overridden);
4213 if (ObjCMethod->isImplicit() && overridden->isImplicit())
4214 continue; // Conflicting properties are detected elsewhere.
4216 // Check for overriding methods
4217 if (isa<ObjCInterfaceDecl>(ObjCMethod->getDeclContext()) ||
4218 isa<ObjCImplementationDecl>(ObjCMethod->getDeclContext()))
4219 CheckConflictingOverridingMethod(ObjCMethod, overridden,
4220 isa<ObjCProtocolDecl>(overridden->getDeclContext()));
4222 if (CurrentClass && overridden->getDeclContext() != CurrentClass &&
4223 isa<ObjCInterfaceDecl>(overridden->getDeclContext()) &&
4224 !overridden->isImplicit() /* not meant for properties */) {
4225 ObjCMethodDecl::param_iterator ParamI = ObjCMethod->param_begin(),
4226 E = ObjCMethod->param_end();
4227 ObjCMethodDecl::param_iterator PrevI = overridden->param_begin(),
4228 PrevE = overridden->param_end();
4229 for (; ParamI != E && PrevI != PrevE; ++ParamI, ++PrevI) {
4230 assert(PrevI != overridden->param_end() && "Param mismatch");
4231 QualType T1 = Context.getCanonicalType((*ParamI)->getType());
4232 QualType T2 = Context.getCanonicalType((*PrevI)->getType());
4233 // If type of argument of method in this class does not match its
4234 // respective argument type in the super class method, issue warning;
4235 if (!Context.typesAreCompatible(T1, T2)) {
4236 Diag((*ParamI)->getLocation(), diag::ext_typecheck_base_super)
4238 Diag(overridden->getLocation(), diag::note_previous_declaration);
4245 ObjCMethod->setOverriding(hasOverriddenMethodsInBaseOrProtocol);
4248 /// Merge type nullability from for a redeclaration of the same entity,
4249 /// producing the updated type of the redeclared entity.
4250 static QualType mergeTypeNullabilityForRedecl(Sema &S, SourceLocation loc,
4253 SourceLocation prevLoc,
4255 bool prevUsesCSKeyword) {
4256 // Determine the nullability of both types.
4257 auto nullability = type->getNullability(S.Context);
4258 auto prevNullability = prevType->getNullability(S.Context);
4260 // Easy case: both have nullability.
4261 if (nullability.hasValue() == prevNullability.hasValue()) {
4262 // Neither has nullability; continue.
4266 // The nullabilities are equivalent; do nothing.
4267 if (*nullability == *prevNullability)
4270 // Complain about mismatched nullability.
4271 S.Diag(loc, diag::err_nullability_conflicting)
4272 << DiagNullabilityKind(*nullability, usesCSKeyword)
4273 << DiagNullabilityKind(*prevNullability, prevUsesCSKeyword);
4277 // If it's the redeclaration that has nullability, don't change anything.
4281 // Otherwise, provide the result with the same nullability.
4282 return S.Context.getAttributedType(
4283 AttributedType::getNullabilityAttrKind(*prevNullability),
4287 /// Merge information from the declaration of a method in the \@interface
4288 /// (or a category/extension) into the corresponding method in the
4289 /// @implementation (for a class or category).
4290 static void mergeInterfaceMethodToImpl(Sema &S,
4291 ObjCMethodDecl *method,
4292 ObjCMethodDecl *prevMethod) {
4293 // Merge the objc_requires_super attribute.
4294 if (prevMethod->hasAttr<ObjCRequiresSuperAttr>() &&
4295 !method->hasAttr<ObjCRequiresSuperAttr>()) {
4296 // merge the attribute into implementation.
4298 ObjCRequiresSuperAttr::CreateImplicit(S.Context,
4299 method->getLocation()));
4302 // Merge nullability of the result type.
4303 QualType newReturnType
4304 = mergeTypeNullabilityForRedecl(
4305 S, method->getReturnTypeSourceRange().getBegin(),
4306 method->getReturnType(),
4307 method->getObjCDeclQualifier() & Decl::OBJC_TQ_CSNullability,
4308 prevMethod->getReturnTypeSourceRange().getBegin(),
4309 prevMethod->getReturnType(),
4310 prevMethod->getObjCDeclQualifier() & Decl::OBJC_TQ_CSNullability);
4311 method->setReturnType(newReturnType);
4313 // Handle each of the parameters.
4314 unsigned numParams = method->param_size();
4315 unsigned numPrevParams = prevMethod->param_size();
4316 for (unsigned i = 0, n = std::min(numParams, numPrevParams); i != n; ++i) {
4317 ParmVarDecl *param = method->param_begin()[i];
4318 ParmVarDecl *prevParam = prevMethod->param_begin()[i];
4320 // Merge nullability.
4321 QualType newParamType
4322 = mergeTypeNullabilityForRedecl(
4323 S, param->getLocation(), param->getType(),
4324 param->getObjCDeclQualifier() & Decl::OBJC_TQ_CSNullability,
4325 prevParam->getLocation(), prevParam->getType(),
4326 prevParam->getObjCDeclQualifier() & Decl::OBJC_TQ_CSNullability);
4327 param->setType(newParamType);
4331 /// Verify that the method parameters/return value have types that are supported
4332 /// by the x86 target.
4333 static void checkObjCMethodX86VectorTypes(Sema &SemaRef,
4334 const ObjCMethodDecl *Method) {
4335 assert(SemaRef.getASTContext().getTargetInfo().getTriple().getArch() ==
4336 llvm::Triple::x86 &&
4337 "x86-specific check invoked for a different target");
4340 for (const ParmVarDecl *P : Method->parameters()) {
4341 if (P->getType()->isVectorType()) {
4342 Loc = P->getLocStart();
4347 if (Loc.isInvalid()) {
4348 if (Method->getReturnType()->isVectorType()) {
4349 Loc = Method->getReturnTypeSourceRange().getBegin();
4350 T = Method->getReturnType();
4355 // Vector parameters/return values are not supported by objc_msgSend on x86 in
4356 // iOS < 9 and macOS < 10.11.
4357 const auto &Triple = SemaRef.getASTContext().getTargetInfo().getTriple();
4358 VersionTuple AcceptedInVersion;
4359 if (Triple.getOS() == llvm::Triple::IOS)
4360 AcceptedInVersion = VersionTuple(/*Major=*/9);
4361 else if (Triple.isMacOSX())
4362 AcceptedInVersion = VersionTuple(/*Major=*/10, /*Minor=*/11);
4365 if (SemaRef.getASTContext().getTargetInfo().getPlatformMinVersion() >=
4368 SemaRef.Diag(Loc, diag::err_objc_method_unsupported_param_ret_type)
4369 << T << (Method->getReturnType()->isVectorType() ? /*return value*/ 1
4371 << (Triple.isMacOSX() ? "macOS 10.11" : "iOS 9");
4374 Decl *Sema::ActOnMethodDeclaration(
4376 SourceLocation MethodLoc, SourceLocation EndLoc,
4377 tok::TokenKind MethodType,
4378 ObjCDeclSpec &ReturnQT, ParsedType ReturnType,
4379 ArrayRef<SourceLocation> SelectorLocs,
4381 // optional arguments. The number of types/arguments is obtained
4382 // from the Sel.getNumArgs().
4383 ObjCArgInfo *ArgInfo,
4384 DeclaratorChunk::ParamInfo *CParamInfo, unsigned CNumArgs, // c-style args
4385 AttributeList *AttrList, tok::ObjCKeywordKind MethodDeclKind,
4386 bool isVariadic, bool MethodDefinition) {
4387 // Make sure we can establish a context for the method.
4388 if (!CurContext->isObjCContainer()) {
4389 Diag(MethodLoc, diag::err_missing_method_context);
4392 ObjCContainerDecl *OCD = dyn_cast<ObjCContainerDecl>(CurContext);
4393 Decl *ClassDecl = cast<Decl>(OCD);
4394 QualType resultDeclType;
4396 bool HasRelatedResultType = false;
4397 TypeSourceInfo *ReturnTInfo = nullptr;
4399 resultDeclType = GetTypeFromParser(ReturnType, &ReturnTInfo);
4401 if (CheckFunctionReturnType(resultDeclType, MethodLoc))
4404 QualType bareResultType = resultDeclType;
4405 (void)AttributedType::stripOuterNullability(bareResultType);
4406 HasRelatedResultType = (bareResultType == Context.getObjCInstanceType());
4407 } else { // get the type for "id".
4408 resultDeclType = Context.getObjCIdType();
4409 Diag(MethodLoc, diag::warn_missing_method_return_type)
4410 << FixItHint::CreateInsertion(SelectorLocs.front(), "(id)");
4413 ObjCMethodDecl *ObjCMethod = ObjCMethodDecl::Create(
4414 Context, MethodLoc, EndLoc, Sel, resultDeclType, ReturnTInfo, CurContext,
4415 MethodType == tok::minus, isVariadic,
4416 /*isPropertyAccessor=*/false,
4417 /*isImplicitlyDeclared=*/false, /*isDefined=*/false,
4418 MethodDeclKind == tok::objc_optional ? ObjCMethodDecl::Optional
4419 : ObjCMethodDecl::Required,
4420 HasRelatedResultType);
4422 SmallVector<ParmVarDecl*, 16> Params;
4424 for (unsigned i = 0, e = Sel.getNumArgs(); i != e; ++i) {
4428 if (!ArgInfo[i].Type) {
4429 ArgType = Context.getObjCIdType();
4432 ArgType = GetTypeFromParser(ArgInfo[i].Type, &DI);
4435 LookupResult R(*this, ArgInfo[i].Name, ArgInfo[i].NameLoc,
4436 LookupOrdinaryName, ForRedeclaration);
4438 if (R.isSingleResult()) {
4439 NamedDecl *PrevDecl = R.getFoundDecl();
4440 if (S->isDeclScope(PrevDecl)) {
4441 Diag(ArgInfo[i].NameLoc,
4442 (MethodDefinition ? diag::warn_method_param_redefinition
4443 : diag::warn_method_param_declaration))
4445 Diag(PrevDecl->getLocation(),
4446 diag::note_previous_declaration);
4450 SourceLocation StartLoc = DI
4451 ? DI->getTypeLoc().getBeginLoc()
4452 : ArgInfo[i].NameLoc;
4454 ParmVarDecl* Param = CheckParameter(ObjCMethod, StartLoc,
4455 ArgInfo[i].NameLoc, ArgInfo[i].Name,
4456 ArgType, DI, SC_None);
4458 Param->setObjCMethodScopeInfo(i);
4460 Param->setObjCDeclQualifier(
4461 CvtQTToAstBitMask(ArgInfo[i].DeclSpec.getObjCDeclQualifier()));
4463 // Apply the attributes to the parameter.
4464 ProcessDeclAttributeList(TUScope, Param, ArgInfo[i].ArgAttrs);
4465 AddPragmaAttributes(TUScope, Param);
4467 if (Param->hasAttr<BlocksAttr>()) {
4468 Diag(Param->getLocation(), diag::err_block_on_nonlocal);
4469 Param->setInvalidDecl();
4472 IdResolver.AddDecl(Param);
4474 Params.push_back(Param);
4477 for (unsigned i = 0, e = CNumArgs; i != e; ++i) {
4478 ParmVarDecl *Param = cast<ParmVarDecl>(CParamInfo[i].Param);
4479 QualType ArgType = Param->getType();
4480 if (ArgType.isNull())
4481 ArgType = Context.getObjCIdType();
4483 // Perform the default array/function conversions (C99 6.7.5.3p[7,8]).
4484 ArgType = Context.getAdjustedParameterType(ArgType);
4486 Param->setDeclContext(ObjCMethod);
4487 Params.push_back(Param);
4490 ObjCMethod->setMethodParams(Context, Params, SelectorLocs);
4491 ObjCMethod->setObjCDeclQualifier(
4492 CvtQTToAstBitMask(ReturnQT.getObjCDeclQualifier()));
4495 ProcessDeclAttributeList(TUScope, ObjCMethod, AttrList);
4496 AddPragmaAttributes(TUScope, ObjCMethod);
4498 // Add the method now.
4499 const ObjCMethodDecl *PrevMethod = nullptr;
4500 if (ObjCImplDecl *ImpDecl = dyn_cast<ObjCImplDecl>(ClassDecl)) {
4501 if (MethodType == tok::minus) {
4502 PrevMethod = ImpDecl->getInstanceMethod(Sel);
4503 ImpDecl->addInstanceMethod(ObjCMethod);
4505 PrevMethod = ImpDecl->getClassMethod(Sel);
4506 ImpDecl->addClassMethod(ObjCMethod);
4509 // Merge information from the @interface declaration into the
4511 if (ObjCInterfaceDecl *IDecl = ImpDecl->getClassInterface()) {
4512 if (auto *IMD = IDecl->lookupMethod(ObjCMethod->getSelector(),
4513 ObjCMethod->isInstanceMethod())) {
4514 mergeInterfaceMethodToImpl(*this, ObjCMethod, IMD);
4516 // Warn about defining -dealloc in a category.
4517 if (isa<ObjCCategoryImplDecl>(ImpDecl) && IMD->isOverriding() &&
4518 ObjCMethod->getSelector().getMethodFamily() == OMF_dealloc) {
4519 Diag(ObjCMethod->getLocation(), diag::warn_dealloc_in_category)
4520 << ObjCMethod->getDeclName();
4525 cast<DeclContext>(ClassDecl)->addDecl(ObjCMethod);
4529 // You can never have two method definitions with the same name.
4530 Diag(ObjCMethod->getLocation(), diag::err_duplicate_method_decl)
4531 << ObjCMethod->getDeclName();
4532 Diag(PrevMethod->getLocation(), diag::note_previous_declaration);
4533 ObjCMethod->setInvalidDecl();
4537 // If this Objective-C method does not have a related result type, but we
4538 // are allowed to infer related result types, try to do so based on the
4540 ObjCInterfaceDecl *CurrentClass = dyn_cast<ObjCInterfaceDecl>(ClassDecl);
4541 if (!CurrentClass) {
4542 if (ObjCCategoryDecl *Cat = dyn_cast<ObjCCategoryDecl>(ClassDecl))
4543 CurrentClass = Cat->getClassInterface();
4544 else if (ObjCImplDecl *Impl = dyn_cast<ObjCImplDecl>(ClassDecl))
4545 CurrentClass = Impl->getClassInterface();
4546 else if (ObjCCategoryImplDecl *CatImpl
4547 = dyn_cast<ObjCCategoryImplDecl>(ClassDecl))
4548 CurrentClass = CatImpl->getClassInterface();
4551 ResultTypeCompatibilityKind RTC
4552 = CheckRelatedResultTypeCompatibility(*this, ObjCMethod, CurrentClass);
4554 CheckObjCMethodOverrides(ObjCMethod, CurrentClass, RTC);
4556 bool ARCError = false;
4557 if (getLangOpts().ObjCAutoRefCount)
4558 ARCError = CheckARCMethodDecl(ObjCMethod);
4560 // Infer the related result type when possible.
4561 if (!ARCError && RTC == Sema::RTC_Compatible &&
4562 !ObjCMethod->hasRelatedResultType() &&
4563 LangOpts.ObjCInferRelatedResultType) {
4564 bool InferRelatedResultType = false;
4565 switch (ObjCMethod->getMethodFamily()) {
4570 case OMF_mutableCopy:
4572 case OMF_retainCount:
4573 case OMF_initialize:
4574 case OMF_performSelector:
4579 InferRelatedResultType = ObjCMethod->isClassMethod();
4583 case OMF_autorelease:
4586 InferRelatedResultType = ObjCMethod->isInstanceMethod();
4590 if (InferRelatedResultType &&
4591 !ObjCMethod->getReturnType()->isObjCIndependentClassType())
4592 ObjCMethod->SetRelatedResultType();
4595 if (MethodDefinition &&
4596 Context.getTargetInfo().getTriple().getArch() == llvm::Triple::x86)
4597 checkObjCMethodX86VectorTypes(*this, ObjCMethod);
4599 ActOnDocumentableDecl(ObjCMethod);
4604 bool Sema::CheckObjCDeclScope(Decl *D) {
4605 // Following is also an error. But it is caused by a missing @end
4606 // and diagnostic is issued elsewhere.
4607 if (isa<ObjCContainerDecl>(CurContext->getRedeclContext()))
4610 // If we switched context to translation unit while we are still lexically in
4611 // an objc container, it means the parser missed emitting an error.
4612 if (isa<TranslationUnitDecl>(getCurLexicalContext()->getRedeclContext()))
4615 Diag(D->getLocation(), diag::err_objc_decls_may_only_appear_in_global_scope);
4616 D->setInvalidDecl();
4621 /// Called whenever \@defs(ClassName) is encountered in the source. Inserts the
4622 /// instance variables of ClassName into Decls.
4623 void Sema::ActOnDefs(Scope *S, Decl *TagD, SourceLocation DeclStart,
4624 IdentifierInfo *ClassName,
4625 SmallVectorImpl<Decl*> &Decls) {
4626 // Check that ClassName is a valid class
4627 ObjCInterfaceDecl *Class = getObjCInterfaceDecl(ClassName, DeclStart);
4629 Diag(DeclStart, diag::err_undef_interface) << ClassName;
4632 if (LangOpts.ObjCRuntime.isNonFragile()) {
4633 Diag(DeclStart, diag::err_atdef_nonfragile_interface);
4637 // Collect the instance variables
4638 SmallVector<const ObjCIvarDecl*, 32> Ivars;
4639 Context.DeepCollectObjCIvars(Class, true, Ivars);
4640 // For each ivar, create a fresh ObjCAtDefsFieldDecl.
4641 for (unsigned i = 0; i < Ivars.size(); i++) {
4642 const FieldDecl* ID = cast<FieldDecl>(Ivars[i]);
4643 RecordDecl *Record = dyn_cast<RecordDecl>(TagD);
4644 Decl *FD = ObjCAtDefsFieldDecl::Create(Context, Record,
4645 /*FIXME: StartL=*/ID->getLocation(),
4647 ID->getIdentifier(), ID->getType(),
4649 Decls.push_back(FD);
4652 // Introduce all of these fields into the appropriate scope.
4653 for (SmallVectorImpl<Decl*>::iterator D = Decls.begin();
4654 D != Decls.end(); ++D) {
4655 FieldDecl *FD = cast<FieldDecl>(*D);
4656 if (getLangOpts().CPlusPlus)
4657 PushOnScopeChains(cast<FieldDecl>(FD), S);
4658 else if (RecordDecl *Record = dyn_cast<RecordDecl>(TagD))
4659 Record->addDecl(FD);
4663 /// \brief Build a type-check a new Objective-C exception variable declaration.
4664 VarDecl *Sema::BuildObjCExceptionDecl(TypeSourceInfo *TInfo, QualType T,
4665 SourceLocation StartLoc,
4666 SourceLocation IdLoc,
4669 // ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage
4670 // duration shall not be qualified by an address-space qualifier."
4671 // Since all parameters have automatic store duration, they can not have
4672 // an address space.
4673 if (T.getAddressSpace() != 0) {
4674 Diag(IdLoc, diag::err_arg_with_address_space);
4678 // An @catch parameter must be an unqualified object pointer type;
4679 // FIXME: Recover from "NSObject foo" by inserting the * in "NSObject *foo"?
4681 // Don't do any further checking.
4682 } else if (T->isDependentType()) {
4683 // Okay: we don't know what this type will instantiate to.
4684 } else if (!T->isObjCObjectPointerType()) {
4686 Diag(IdLoc ,diag::err_catch_param_not_objc_type);
4687 } else if (T->isObjCQualifiedIdType()) {
4689 Diag(IdLoc, diag::err_illegal_qualifiers_on_catch_parm);
4692 VarDecl *New = VarDecl::Create(Context, CurContext, StartLoc, IdLoc, Id,
4694 New->setExceptionVariable(true);
4696 // In ARC, infer 'retaining' for variables of retainable type.
4697 if (getLangOpts().ObjCAutoRefCount && inferObjCARCLifetime(New))
4701 New->setInvalidDecl();
4705 Decl *Sema::ActOnObjCExceptionDecl(Scope *S, Declarator &D) {
4706 const DeclSpec &DS = D.getDeclSpec();
4708 // We allow the "register" storage class on exception variables because
4709 // GCC did, but we drop it completely. Any other storage class is an error.
4710 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) {
4711 Diag(DS.getStorageClassSpecLoc(), diag::warn_register_objc_catch_parm)
4712 << FixItHint::CreateRemoval(SourceRange(DS.getStorageClassSpecLoc()));
4713 } else if (DeclSpec::SCS SCS = DS.getStorageClassSpec()) {
4714 Diag(DS.getStorageClassSpecLoc(), diag::err_storage_spec_on_catch_parm)
4715 << DeclSpec::getSpecifierName(SCS);
4717 if (DS.isInlineSpecified())
4718 Diag(DS.getInlineSpecLoc(), diag::err_inline_non_function)
4719 << getLangOpts().CPlusPlus1z;
4720 if (DeclSpec::TSCS TSCS = D.getDeclSpec().getThreadStorageClassSpec())
4721 Diag(D.getDeclSpec().getThreadStorageClassSpecLoc(),
4722 diag::err_invalid_thread)
4723 << DeclSpec::getSpecifierName(TSCS);
4724 D.getMutableDeclSpec().ClearStorageClassSpecs();
4726 DiagnoseFunctionSpecifiers(D.getDeclSpec());
4728 // Check that there are no default arguments inside the type of this
4729 // exception object (C++ only).
4730 if (getLangOpts().CPlusPlus)
4731 CheckExtraCXXDefaultArguments(D);
4733 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S);
4734 QualType ExceptionType = TInfo->getType();
4736 VarDecl *New = BuildObjCExceptionDecl(TInfo, ExceptionType,
4737 D.getSourceRange().getBegin(),
4738 D.getIdentifierLoc(),
4742 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1).
4743 if (D.getCXXScopeSpec().isSet()) {
4744 Diag(D.getIdentifierLoc(), diag::err_qualified_objc_catch_parm)
4745 << D.getCXXScopeSpec().getRange();
4746 New->setInvalidDecl();
4749 // Add the parameter declaration into this scope.
4751 if (D.getIdentifier())
4752 IdResolver.AddDecl(New);
4754 ProcessDeclAttributes(S, New, D);
4756 if (New->hasAttr<BlocksAttr>())
4757 Diag(New->getLocation(), diag::err_block_on_nonlocal);
4761 /// CollectIvarsToConstructOrDestruct - Collect those ivars which require
4763 void Sema::CollectIvarsToConstructOrDestruct(ObjCInterfaceDecl *OI,
4764 SmallVectorImpl<ObjCIvarDecl*> &Ivars) {
4765 for (ObjCIvarDecl *Iv = OI->all_declared_ivar_begin(); Iv;
4766 Iv= Iv->getNextIvar()) {
4767 QualType QT = Context.getBaseElementType(Iv->getType());
4768 if (QT->isRecordType())
4769 Ivars.push_back(Iv);
4773 void Sema::DiagnoseUseOfUnimplementedSelectors() {
4774 // Load referenced selectors from the external source.
4775 if (ExternalSource) {
4776 SmallVector<std::pair<Selector, SourceLocation>, 4> Sels;
4777 ExternalSource->ReadReferencedSelectors(Sels);
4778 for (unsigned I = 0, N = Sels.size(); I != N; ++I)
4779 ReferencedSelectors[Sels[I].first] = Sels[I].second;
4782 // Warning will be issued only when selector table is
4783 // generated (which means there is at lease one implementation
4784 // in the TU). This is to match gcc's behavior.
4785 if (ReferencedSelectors.empty() ||
4786 !Context.AnyObjCImplementation())
4788 for (auto &SelectorAndLocation : ReferencedSelectors) {
4789 Selector Sel = SelectorAndLocation.first;
4790 SourceLocation Loc = SelectorAndLocation.second;
4791 if (!LookupImplementedMethodInGlobalPool(Sel))
4792 Diag(Loc, diag::warn_unimplemented_selector) << Sel;
4797 Sema::GetIvarBackingPropertyAccessor(const ObjCMethodDecl *Method,
4798 const ObjCPropertyDecl *&PDecl) const {
4799 if (Method->isClassMethod())
4801 const ObjCInterfaceDecl *IDecl = Method->getClassInterface();
4804 Method = IDecl->lookupMethod(Method->getSelector(), /*isInstance=*/true,
4805 /*shallowCategoryLookup=*/false,
4806 /*followSuper=*/false);
4807 if (!Method || !Method->isPropertyAccessor())
4809 if ((PDecl = Method->findPropertyDecl()))
4810 if (ObjCIvarDecl *IV = PDecl->getPropertyIvarDecl()) {
4811 // property backing ivar must belong to property's class
4812 // or be a private ivar in class's implementation.
4813 // FIXME. fix the const-ness issue.
4814 IV = const_cast<ObjCInterfaceDecl *>(IDecl)->lookupInstanceVariable(
4815 IV->getIdentifier());
4822 /// Used by Sema::DiagnoseUnusedBackingIvarInAccessor to check if a property
4823 /// accessor references the backing ivar.
4824 class UnusedBackingIvarChecker :
4825 public RecursiveASTVisitor<UnusedBackingIvarChecker> {
4828 const ObjCMethodDecl *Method;
4829 const ObjCIvarDecl *IvarD;
4831 bool InvokedSelfMethod;
4833 UnusedBackingIvarChecker(Sema &S, const ObjCMethodDecl *Method,
4834 const ObjCIvarDecl *IvarD)
4835 : S(S), Method(Method), IvarD(IvarD),
4836 AccessedIvar(false), InvokedSelfMethod(false) {
4840 bool VisitObjCIvarRefExpr(ObjCIvarRefExpr *E) {
4841 if (E->getDecl() == IvarD) {
4842 AccessedIvar = true;
4848 bool VisitObjCMessageExpr(ObjCMessageExpr *E) {
4849 if (E->getReceiverKind() == ObjCMessageExpr::Instance &&
4850 S.isSelfExpr(E->getInstanceReceiver(), Method)) {
4851 InvokedSelfMethod = true;
4856 } // end anonymous namespace
4858 void Sema::DiagnoseUnusedBackingIvarInAccessor(Scope *S,
4859 const ObjCImplementationDecl *ImplD) {
4860 if (S->hasUnrecoverableErrorOccurred())
4863 for (const auto *CurMethod : ImplD->instance_methods()) {
4864 unsigned DIAG = diag::warn_unused_property_backing_ivar;
4865 SourceLocation Loc = CurMethod->getLocation();
4866 if (Diags.isIgnored(DIAG, Loc))
4869 const ObjCPropertyDecl *PDecl;
4870 const ObjCIvarDecl *IV = GetIvarBackingPropertyAccessor(CurMethod, PDecl);
4874 UnusedBackingIvarChecker Checker(*this, CurMethod, IV);
4875 Checker.TraverseStmt(CurMethod->getBody());
4876 if (Checker.AccessedIvar)
4879 // Do not issue this warning if backing ivar is used somewhere and accessor
4880 // implementation makes a self call. This is to prevent false positive in
4881 // cases where the ivar is accessed by another method that the accessor
4883 if (!IV->isReferenced() || !Checker.InvokedSelfMethod) {
4884 Diag(Loc, DIAG) << IV;
4885 Diag(PDecl->getLocation(), diag::note_property_declare);