Redeclare Objective-C property accessors inside the ObjCImplDecl in which they are synthesized.

[aprantl]

Summary

This patch is motivated by (and factored out from) https://reviews.llvm.org/D66121 which is a debug info bugfix. Starting with DWARF 5 all Objective-C methods are nested inside their containing type, and that patch implements this for synthesized Objective-C properties.

This patch became much longer than I hoped it would be but most of the changes are mechanical in nature.

1. SemaObjCProperty populates a list of synthesized accessors that may need to inserted into an ObjCImplDecl.
2. SemaDeclObjC::ActOnEnd inserts forward-declarations for all accessors for which no override was provided into their ObjCImplDecl. This patch does *not* synthesize AST function *bodies*. Moving that code from the static analyzer into Sema may be a good idea though.
3. Places that expect all methods to have bodies have been updated.

Most of the updates are very straightforward, the most irritating part was updating the static analyzer, there may be a more elegant way to do this.
I'm somewhat concerned that I didn't have to update the GNU Objective-C runtime for the testsuite to pass. I did not update the static analyzer's inliner for synthesized properties to point back to the property declaration (see test/Analysis/Inputs/expected-plists/nullability-notes.m.plist), which I believed to be more bug than a feature.

[aprantl]

Remove #if 0 from test I used during debugging. (It still passes!)

[theraven]

The changes for the GNU runtimes look correct to me. We're missing a bunch of tests there, unfortunately.

[rjmccall]

clang/include/clang/AST/DeclObjC.h

2797

Are these comments right? The DC is the implementation's interface?

Regardless, I think these comments are misleading: the right way to put this is that these are the getter and setter method *definitions* (even if they don't necessarily have a body). And, relatedly, you should mention whether these are set even if the methods are defined explicitly or only if they're synthesized.

clang/include/clang/Sema/Sema.h

8522 ↗

(On Diff #222056)

Property accessors are created in the @implementation if they aren't defined explicitly there.

Does this really need to be global state on Sema? Does it theoretically need to be serialized and restored if e.g. a translation-unit prefix is cut after an @implementation is seen?

clang/lib/AST/DeclObjC.cpp

1386

Can you just do this as a simple check to look through the ObjCImplDecl to the ObjCInterfaceDecl as the first thing, immediately after you initialize Container?

clang/lib/Analysis/BodyFarm.cpp

852

Why did this logic need to change?

clang/lib/CodeGen/CGObjCGNU.cpp

1888

This is only correct if these methods aren't defined explicitly by the user, right? Or do this methods return null in that case?

Same question goes for the CGObjCMac code.

clang/lib/CodeGen/CGObjCMac.cpp

6697

Spurious change.

clang/lib/CodeGen/CodeGenFunction.cpp

694

Spurious change.

clang/lib/CodeGen/CodeGenModule.cpp

5124

Is this special treatment still necessary? Won't we encounter the getter and setter on the normal pass over the method definitions in the @implementation?

[rjmccall]

Also, I think it would be good if there was a more explicit method for asking whether a method is a synthesized definition. Basically, there's a tri-state: there are pure declarations, user-provided definitions, and synthetic definitions. IRGen should emit a function when it sees either of the latter two, but it might have to use special code for synthetic definitions.

[aprantl]

clang/lib/Analysis/BodyFarm.cpp

852

I don't have a satisfying answer for this.

Without this extra code, the assertion in https://github.com/llvm/llvm-project/blob/b081220cfd46965fa25dbf826cd3f42f4f9e54cd/clang/test/Analysis/properties.m#L1035 (and only that one) turns from UNKNOWN to TRUE.

There is a similar workaround with a similar comment in
https://github.com/llvm/llvm-project/blob/b081220cfd46965fa25dbf826cd3f42f4f9e54cd/clang/lib/StaticAnalyzer/Core/CallEvent.cpp#L1291
that looks like it is related.

clang/lib/CodeGen/CodeGenModule.cpp

5124

We don't know which ObjMethodDecls without bodies are property accessor implementations since there is no pointer from the ObjCMethodDecl back to the ObjCPropertyImplDecl.

[aprantl]

Addressed most of the feedback, explained the rest.

[NoQ]

clang/test/Analysis/Inputs/expected-plists/nullability-notes.m.plist

191

It looks like the body farm for the property accessor has stopped working here. The code under analysis (from test/Analysis/nullability-notes.m) is:

 7	void takesNonnull(NSObject *_Nonnull y);
 8
 9	@interface ClassWithProperties: NSObject
10	@property(copy, nullable) NSObject *x; // plist check ensures no control flow piece from here to 'self.x'.
11	-(void) method;
12	@end;
13	@implementation ClassWithProperties
14	-(void) method {
15	  // no-crash
16	  NSObject *x = self.x; // expected-note{{Nullability 'nullable' is inferred}}
17	  takesNonnull(x); // expected-warning{{Nullable pointer is passed to a callee that requires a non-null 1st parameter}}
18	                   // expected-note@-1{{Nullable pointer is passed to a callee that requires a non-null 1st parameter}}
19	}
20	@end

The point of the test is to check how control flow is displayed to the user, and this change in the plist file will not really be visible to the user. However i'm worried that we've lost precision of the analysis on similar examples. I'll double-check.

[rjmccall]

clang/lib/CodeGen/CodeGenModule.cpp

5124

I mean, this doesn't seem like an unreasonable thing to be able to discover given just an ObjCMethodDecl. We can certainly set something on the declaration that says that it represents a synthesized method definition (and is therefore a definition for the purposes of isDefined or anything similar).

[aprantl]

Rebased patch and made it slightly more explicit whether an ObjCMethodDecl is a synthesized accessor stub by reserving a bit for it in ObjCMethodDecl.

[aprantl]

clang/lib/CodeGen/CodeGenModule.cpp

5124

If we were to move this into the loop / function that emits each method decl, we would still somehow need to get back to the ObjCPropertyImplDecl . There is no pointer in that direction, so we'd have to loop over all property impls until we find it. This here is going to be faster. Storing a pointer to a possible ObjCPropertyImplDecl in ObjCMethodDecl seems wasteful. Let me know if I misunderstood what you were suggesting.

[aprantl]

Accidentally sent my diff-upon-previous-diff instead of diff against master.

[rjmccall]

Okay, thanks for patiently working through all this review. I'm happy with this now.

clang/lib/CodeGen/CodeGenModule.cpp

5124

Oh, in order to find the associated ivar? I hadn't considered that. Okay, WFM.

[aprantl]

Thanks for patiently working through this with me.

clang/include/clang/AST/DeclBase.h

class ObjCMethodDeclBitfields {
 
     /// instance (true) or class (false) method.
     uint64_t IsInstance : 1;
     uint64_t IsVariadic : 1;
 
     /// True if this method is the getter or setter for an explicit property.
     uint64_t IsPropertyAccessor : 1;
 
+    /// True if this method is a synthesized property accessor stub.
+    uint64_t IsSynthesizedAccessorStub : 1;
+
     /// Method has a definition.
     uint64_t IsDefined : 1;
 
     /// Method redeclaration in the same interface.
     uint64_t IsRedeclaration : 1;
 
     /// Is redeclared in the same interface.
     mutable uint64_t HasRedeclaration : 1;

clang/include/clang/AST/DeclObjC.h

private:
   /// CmdDecl - Decl for the implicit _cmd parameter. This is lazily
   /// constructed by createImplicitParams.
   ImplicitParamDecl *CmdDecl = nullptr;
 
   ObjCMethodDecl(SourceLocation beginLoc, SourceLocation endLoc,
                  Selector SelInfo, QualType T, TypeSourceInfo *ReturnTInfo,
                  DeclContext *contextDecl, bool isInstance = true,
                  bool isVariadic = false, bool isPropertyAccessor = false,
+                 bool isSynthesizedAccessorStub = false, 
                  bool isImplicitlyDeclared = false, bool isDefined = false,
                  ImplementationControl impControl = None,
                  bool HasRelatedResultType = false);
 
   SelectorLocationsKind getSelLocsKind() const {
     return static_cast<SelectorLocationsKind>(ObjCMethodDeclBits.SelLocsKind);
   }
 
public:
   friend class ASTDeclReader;
   friend class ASTDeclWriter;
 
   static ObjCMethodDecl *
   Create(ASTContext &C, SourceLocation beginLoc, SourceLocation endLoc,
          Selector SelInfo, QualType T, TypeSourceInfo *ReturnTInfo,
          DeclContext *contextDecl, bool isInstance = true,
          bool isVariadic = false, bool isPropertyAccessor = false,
+         bool isSynthesizedAccessorStub = false,
          bool isImplicitlyDeclared = false, bool isDefined = false,
          ImplementationControl impControl = None,
          bool HasRelatedResultType = false);
 
   static ObjCMethodDecl *CreateDeserialized(ASTContext &C, unsigned ID);
 
   ObjCMethodDecl *getCanonicalDecl() override;
   const ObjCMethodDecl *getCanonicalDecl() const {
public:
   bool isPropertyAccessor() const {
     return ObjCMethodDeclBits.IsPropertyAccessor;
   }
 
   void setPropertyAccessor(bool isAccessor) {
     ObjCMethodDeclBits.IsPropertyAccessor = isAccessor;
   }
 
+  bool isSynthesizedAccessorStub() const {
+    return ObjCMethodDeclBits.IsSynthesizedAccessorStub;
+  }
+
+  void setSynthesizedAccessorStub(bool isSynthesizedAccessorStub) {
+    ObjCMethodDeclBits.IsSynthesizedAccessorStub = isSynthesizedAccessorStub;
+  }
+
   bool isDefined() const { return ObjCMethodDeclBits.IsDefined; }
   void setDefined(bool isDefined) { ObjCMethodDeclBits.IsDefined = isDefined; }
 
   /// Whether this method overrides any other in the class hierarchy.
   ///
   /// A method is said to override any method in the class's
   /// base classes, its protocols, or its categories' protocols, that has
   /// the same selector and is of the same kind (class or instance).
private:
   SourceLocation IvarLoc;
 
   /// Property declaration being implemented
   ObjCPropertyDecl *PropertyDecl;
 
   /// Null for \@dynamic. Required for \@synthesize.
   ObjCIvarDecl *PropertyIvarDecl;
 
+  /// The getter's definition, which has an empty body if synthesized.
+  ObjCMethodDecl *GetterMethodDecl = nullptr;
+  /// The getter's definition, which has an empty body if synthesized.
+  ObjCMethodDecl *SetterMethodDecl = nullptr;
+
   /// Null for \@dynamic. Non-null if property must be copy-constructed in
   /// getter.
   Expr *GetterCXXConstructor = nullptr;
 
   /// Null for \@dynamic. Non-null if property has assignment operator to call
   /// in Setter synthesis.
   Expr *SetterCXXAssignment = nullptr;
 
   ObjCPropertyImplDecl(DeclContext *DC, SourceLocation atLoc, SourceLocation L,
public:
   /// \code
   /// \@synthesize int a = b; // true
   /// \@synthesize int a; // false
   /// \endcode
   bool isIvarNameSpecified() const {
     return IvarLoc.isValid() && IvarLoc != getLocation();
   }
 
+  ObjCMethodDecl *getGetterMethodDecl() const { return GetterMethodDecl; }
+  void setGetterMethodDecl(ObjCMethodDecl *MD) { GetterMethodDecl = MD; }
+
+  ObjCMethodDecl *getSetterMethodDecl() const { return SetterMethodDecl; }
+  void setSetterMethodDecl(ObjCMethodDecl *MD) { SetterMethodDecl = MD; }
+
   Expr *getGetterCXXConstructor() const {
     return GetterCXXConstructor;
   }
 
   void setGetterCXXConstructor(Expr *getterCXXConstructor) {
     GetterCXXConstructor = getterCXXConstructor;
   }
 

clang/lib/AST/ASTImporter.cpp

ExpectedDecl ASTNodeImporter::VisitObjCMethodDecl(ObjCMethodDecl *D) {
   if (auto Imp = importSeq(
       D->getEndLoc(), D->getReturnType(), D->getReturnTypeSourceInfo()))
     std::tie(ToEndLoc, ToReturnType, ToReturnTypeSourceInfo) = *Imp;
   else
     return Imp.takeError();
 
   ObjCMethodDecl *ToMethod;
   if (GetImportedOrCreateDecl(
-          ToMethod, D, Importer.getToContext(), Loc,
-          ToEndLoc, Name.getObjCSelector(), ToReturnType,
-          ToReturnTypeSourceInfo, DC, D->isInstanceMethod(), D->isVariadic(),
-          D->isPropertyAccessor(), D->isImplicit(), D->isDefined(),
+          ToMethod, D, Importer.getToContext(), Loc, ToEndLoc,
+          Name.getObjCSelector(), ToReturnType, ToReturnTypeSourceInfo, DC,
+          D->isInstanceMethod(), D->isVariadic(), D->isPropertyAccessor(),
+          D->isSynthesizedAccessorStub(), D->isImplicit(), D->isDefined(),
           D->getImplementationControl(), D->hasRelatedResultType()))
     return ToMethod;
 
   // FIXME: When we decide to merge method definitions, we'll need to
   // deal with implicit parameters.
 
   // Import the parameters
   SmallVector<ParmVarDecl *, 5> ToParams;

clang/lib/AST/DeclObjC.cpp

if (!Method && getSuperClass())
     return getSuperClass()->lookupPrivateMethod(Sel, Instance);
   return Method;
 }
 
 //===----------------------------------------------------------------------===//
 // ObjCMethodDecl
 //===----------------------------------------------------------------------===//
 
-ObjCMethodDecl::ObjCMethodDecl(SourceLocation beginLoc, SourceLocation endLoc,
-                               Selector SelInfo, QualType T,
-                               TypeSourceInfo *ReturnTInfo,
-                               DeclContext *contextDecl, bool isInstance,
-                               bool isVariadic, bool isPropertyAccessor,
-                               bool isImplicitlyDeclared, bool isDefined,
-                               ImplementationControl impControl,
-                               bool HasRelatedResultType)
+ObjCMethodDecl::ObjCMethodDecl(
+    SourceLocation beginLoc, SourceLocation endLoc, Selector SelInfo,
+    QualType T, TypeSourceInfo *ReturnTInfo, DeclContext *contextDecl,
+    bool isInstance, bool isVariadic, bool isPropertyAccessor,
+    bool isSynthesizedAccessorStub, bool isImplicitlyDeclared, bool isDefined,
+    ImplementationControl impControl, bool HasRelatedResultType)
     : NamedDecl(ObjCMethod, contextDecl, beginLoc, SelInfo),
       DeclContext(ObjCMethod), MethodDeclType(T), ReturnTInfo(ReturnTInfo),
       DeclEndLoc(endLoc) {
 
   // Initialized the bits stored in DeclContext.
   ObjCMethodDeclBits.Family =
       static_cast<ObjCMethodFamily>(InvalidObjCMethodFamily);
   setInstanceMethod(isInstance);
   setVariadic(isVariadic);
   setPropertyAccessor(isPropertyAccessor);
+  setSynthesizedAccessorStub(isSynthesizedAccessorStub);
   setDefined(isDefined);
   setIsRedeclaration(false);
   setHasRedeclaration(false);
   setDeclImplementation(impControl);
   setObjCDeclQualifier(OBJC_TQ_None);
   setRelatedResultType(HasRelatedResultType);
   setSelLocsKind(SelLoc_StandardNoSpace);
   setOverriding(false);
   setHasSkippedBody(false);
 
   setImplicit(isImplicitlyDeclared);
 }
 
 ObjCMethodDecl *ObjCMethodDecl::Create(
     ASTContext &C, SourceLocation beginLoc, SourceLocation endLoc,
     Selector SelInfo, QualType T, TypeSourceInfo *ReturnTInfo,
     DeclContext *contextDecl, bool isInstance, bool isVariadic,
-    bool isPropertyAccessor, bool isImplicitlyDeclared, bool isDefined,
-    ImplementationControl impControl, bool HasRelatedResultType) {
+    bool isPropertyAccessor, bool isSynthesizedAccessorStub,
+    bool isImplicitlyDeclared, bool isDefined, ImplementationControl impControl,
+    bool HasRelatedResultType) {
   return new (C, contextDecl) ObjCMethodDecl(
       beginLoc, endLoc, SelInfo, T, ReturnTInfo, contextDecl, isInstance,
-      isVariadic, isPropertyAccessor, isImplicitlyDeclared, isDefined,
-      impControl, HasRelatedResultType);
+      isVariadic, isPropertyAccessor, isSynthesizedAccessorStub,
+      isImplicitlyDeclared, isDefined, impControl, HasRelatedResultType);
 }
 
 ObjCMethodDecl *ObjCMethodDecl::CreateDeserialized(ASTContext &C, unsigned ID) {
   return new (C, ID) ObjCMethodDecl(SourceLocation(), SourceLocation(),
                                     Selector(), QualType(), nullptr, nullptr);
 }
 
 bool ObjCMethodDecl::isThisDeclarationADesignatedInitializer() const {

 ObjCMethodDecl::findPropertyDecl(bool CheckOverrides) const {
   Selector Sel = getSelector();
   unsigned NumArgs = Sel.getNumArgs();
   if (NumArgs > 1)
     return nullptr;
 
   if (isPropertyAccessor()) {
     const auto *Container = cast<ObjCContainerDecl>(getParent());
+    // For accessor stubs, go back to the interface.
+    if (auto *ImplDecl = dyn_cast<ObjCImplDecl>(Container))
+      if (isSynthesizedAccessorStub())
+        Container = ImplDecl->getClassInterface();
+
     bool IsGetter = (NumArgs == 0);
     bool IsInstance = isInstanceMethod();
 
     /// Local function that attempts to find a matching property within the
     /// given Objective-C container.
     auto findMatchingProperty =
       [&](const ObjCContainerDecl *Container) -> const ObjCPropertyDecl * {
       if (IsInstance) {
if (ClassDecl) {
         if (Ext == Container)
           continue;
 
         if (const auto *Found = findMatchingProperty(Ext))
           return Found;
       }
     }
 
+    assert(isSynthesizedAccessorStub() && "expected an accessor stub");
+    for (const auto *Cat : ClassDecl->known_categories()) {
+      if (Cat == Container)
+        continue;
+
+      if (const auto *Found = findMatchingProperty(Cat))
+        return Found;
+    }
+
     llvm_unreachable("Marked as a property accessor but no property found!");
   }
 
   if (!CheckOverrides)
     return nullptr;
 
   using OverridesTy = SmallVector<const ObjCMethodDecl *, 8>;
 
   OverridesTy Overrides;
   getOverriddenMethods(Overrides);
   for (const auto *Override : Overrides)
     if (const ObjCPropertyDecl *Prop = Override->findPropertyDecl(false))
       return Prop;
 
   return nullptr;
 }
 
 //===----------------------------------------------------------------------===//
 // ObjCTypeParamDecl
 //===----------------------------------------------------------------------===//

clang/lib/Analysis/BodyFarm.cpp

Stmt *BodyFarm::getBody(const ObjCMethodDecl *D) {
   // warning in the following common scenario:
   //
   //  id foo = [[NSObject alloc] init];
   //  self.foo = foo; // We should warn that foo leaks here.
   //
   if (D->param_size() != 0)
     return nullptr;
 
+  // If the property was defined in an extension, search the extensions for
+  // overrides.
+  const ObjCInterfaceDecl *OID = D->getClassInterface();
+  if (dyn_cast<ObjCInterfaceDecl>(D->getParent()) != OID)
+    for (auto *Ext : OID->known_extensions()) {
+      auto *OMD = Ext->getInstanceMethod(D->getSelector());
+      if (OMD && !OMD->isImplicit())
+        return nullptr;
+    }
+
   Val = createObjCPropertyGetter(C, Prop);
 
   return Val.getValue();
 }

clang/lib/CodeGen/CGObjC.cpp

 /// Generate an Objective-C property getter function.
 ///
 /// The given Decl must be an ObjCImplementationDecl. \@synthesize
 /// is illegal within a category.
 void CodeGenFunction::GenerateObjCGetter(ObjCImplementationDecl *IMP,
                                          const ObjCPropertyImplDecl *PID) {
   llvm::Constant *AtomicHelperFn =
       CodeGenFunction(CGM).GenerateObjCAtomicGetterCopyHelperFunction(PID);
-  const ObjCPropertyDecl *PD = PID->getPropertyDecl();
-  ObjCMethodDecl *OMD = PD->getGetterMethodDecl();
+  ObjCMethodDecl *OMD = PID->getGetterMethodDecl();
   assert(OMD && "Invalid call to generate getter (empty method)");
   StartObjCMethod(OMD, IMP->getClassInterface());
 
   generateObjCGetterBody(IMP, PID, OMD, AtomicHelperFn);
 
   FinishFunction();
 }
 
else {
       emitCPPObjectAtomicGetterCall(*this, ReturnValue.getPointer(),
                                     ivar, AtomicHelperFn);
     }
     return;
   }
 
   const ObjCPropertyDecl *prop = propImpl->getPropertyDecl();
   QualType propType = prop->getType();
-  ObjCMethodDecl *getterMethod = prop->getGetterMethodDecl();
+  ObjCMethodDecl *getterMethod = propImpl->getGetterMethodDecl();
 
   ObjCIvarDecl *ivar = propImpl->getPropertyIvarDecl();
 
   // Pick an implementation strategy.
   PropertyImplStrategy strategy(CGM, propImpl);
   switch (strategy.getKind()) {
   case PropertyImplStrategy::Native: {
     // We don't need to do anything for a zero-size struct.
if (CGM.getLangOpts().getGC() != LangOptions::NonGC)
     return false;
   return CGM.getLangOpts().ObjCRuntime.hasOptimizedSetter();
 }
 
 void
 CodeGenFunction::generateObjCSetterBody(const ObjCImplementationDecl *classImpl,
                                         const ObjCPropertyImplDecl *propImpl,
                                         llvm::Constant *AtomicHelperFn) {
-  const ObjCPropertyDecl *prop = propImpl->getPropertyDecl();
   ObjCIvarDecl *ivar = propImpl->getPropertyIvarDecl();
-  ObjCMethodDecl *setterMethod = prop->getSetterMethodDecl();
+  ObjCMethodDecl *setterMethod = propImpl->getSetterMethodDecl();
 
   // Just use the setter expression if Sema gave us one and it's
   // non-trivial.
   if (!hasTrivialSetExpr(propImpl)) {
     if (!AtomicHelperFn)
       // If non-atomic, assignment is called directly.
       EmitStmt(propImpl->getSetterCXXAssignment());
     else

 /// Generate an Objective-C property setter function.
 ///
 /// The given Decl must be an ObjCImplementationDecl. \@synthesize
 /// is illegal within a category.
 void CodeGenFunction::GenerateObjCSetter(ObjCImplementationDecl *IMP,
                                          const ObjCPropertyImplDecl *PID) {
   llvm::Constant *AtomicHelperFn =
       CodeGenFunction(CGM).GenerateObjCAtomicSetterCopyHelperFunction(PID);
-  const ObjCPropertyDecl *PD = PID->getPropertyDecl();
-  ObjCMethodDecl *OMD = PD->getSetterMethodDecl();
+  ObjCMethodDecl *OMD = PID->getSetterMethodDecl();
   assert(OMD && "Invalid call to generate setter (empty method)");
   StartObjCMethod(OMD, IMP->getClassInterface());
 
   generateObjCSetterBody(IMP, PID, AtomicHelperFn);
 
   FinishFunction();
 }
 

clang/lib/CodeGen/CGObjCGNU.cpp

void GenerateClass(const ObjCImplementationDecl *OID) override {
     }
     // struct objc_method_list *methods
     SmallVector<const ObjCMethodDecl*, 16> InstanceMethods;
     InstanceMethods.insert(InstanceMethods.begin(), OID->instmeth_begin(),
         OID->instmeth_end());
     for (auto *propImpl : OID->property_impls())
       if (propImpl->getPropertyImplementation() ==
           ObjCPropertyImplDecl::Synthesize) {
-        ObjCPropertyDecl *prop = propImpl->getPropertyDecl();
-        auto addIfExists = [&](const ObjCMethodDecl* OMD) {
-          if (OMD)
+        auto addIfExists = [&](const ObjCMethodDecl *OMD) {
+          if (OMD && OMD->hasBody())
             InstanceMethods.push_back(OMD);
         };
-        addIfExists(prop->getGetterMethodDecl());
-        addIfExists(prop->getSetterMethodDecl());
+        addIfExists(propImpl->getGetterMethodDecl());
+        addIfExists(propImpl->getSetterMethodDecl());
       }
 
     if (InstanceMethods.size() == 0)
       classFields.addNullPointer(PtrTy);
     else
       classFields.addBitCast(
               GenerateMethodList(className, "", InstanceMethods, false),
               PtrTy);
void CGObjCGNU::GenerateClass(const ObjCImplementationDecl *OID) {
   ClassMethods.insert(ClassMethods.begin(), OID->classmeth_begin(),
       OID->classmeth_end());
 
   // Collect the same information about synthesized properties, which don't
   // show up in the instance method lists.
   for (auto *propertyImpl : OID->property_impls())
     if (propertyImpl->getPropertyImplementation() ==
         ObjCPropertyImplDecl::Synthesize) {
-      ObjCPropertyDecl *property = propertyImpl->getPropertyDecl();
       auto addPropertyMethod = [&](const ObjCMethodDecl *accessor) {
         if (accessor)
           InstanceMethods.push_back(accessor);
       };
-      addPropertyMethod(property->getGetterMethodDecl());
-      addPropertyMethod(property->getSetterMethodDecl());
+      addPropertyMethod(propertyImpl->getGetterMethodDecl());
+      addPropertyMethod(propertyImpl->getSetterMethodDecl());
     }
 
   llvm::Constant *Properties = GeneratePropertyList(OID, ClassDecl);
 
   // Collect the names of referenced protocols
   SmallVector<std::string, 16> Protocols;
   for (const auto *I : ClassDecl->protocols())
     Protocols.push_back(I->getNameAsString());

clang/lib/CodeGen/CGObjCMac.cpp

void CGObjCMac::GenerateClass(const ObjCImplementationDecl *ID) {
   };
   SmallVector<const ObjCMethodDecl *, 16> Methods[NumMethodLists];
   for (const auto *MD : ID->methods()) {
     Methods[unsigned(MD->isClassMethod())].push_back(MD);
   }
 
   for (const auto *PID : ID->property_impls()) {
     if (PID->getPropertyImplementation() == ObjCPropertyImplDecl::Synthesize) {
-      ObjCPropertyDecl *PD = PID->getPropertyDecl();
-
-      if (ObjCMethodDecl *MD = PD->getGetterMethodDecl())
+      if (ObjCMethodDecl *MD = PID->getGetterMethodDecl())
         if (GetMethodDefinition(MD))
           Methods[InstanceMethods].push_back(MD);
-      if (ObjCMethodDecl *MD = PD->getSetterMethodDecl())
+      if (ObjCMethodDecl *MD = PID->getSetterMethodDecl())
         if (GetMethodDefinition(MD))
           Methods[InstanceMethods].push_back(MD);
     }
   }
 
   ConstantInitBuilder builder(CGM);
   auto values = builder.beginStruct(ObjCTypes.ClassTy);
   values.add(EmitMetaClass(ID, Protocols, Methods[ClassMethods]));
llvm::GlobalVariable * CGObjCNonFragileABIMac::BuildClassRoTInitializer(
   // const struct _method_list_t * const baseMethods;
   SmallVector<const ObjCMethodDecl*, 16> methods;
   if (flags & NonFragileABI_Class_Meta) {
     for (const auto *MD : ID->class_methods())
       methods.push_back(MD);
   } else {
     for (const auto *MD : ID->instance_methods())
       methods.push_back(MD);
-
-    for (const auto *PID : ID->property_impls()) {
-      if (PID->getPropertyImplementation() == ObjCPropertyImplDecl::Synthesize){
-        ObjCPropertyDecl *PD = PID->getPropertyDecl();
-
-        if (auto MD = PD->getGetterMethodDecl())
-          if (GetMethodDefinition(MD))
-            methods.push_back(MD);
-        if (auto MD = PD->getSetterMethodDecl())
-          if (GetMethodDefinition(MD))
-            methods.push_back(MD);
-      }
-    }
   }
 
   values.add(emitMethodList(ID->getObjCRuntimeNameAsString(),
                             (flags & NonFragileABI_Class_Meta)
                                ? MethodListType::ClassMethods
                                : MethodListType::InstanceMethods,
                             methods));
 
CGObjCNonFragileABIMac::emitMethodList(Twine name, MethodListType kind,
   auto values = builder.beginStruct();
 
   // sizeof(struct _objc_method)
   unsigned Size = CGM.getDataLayout().getTypeAllocSize(ObjCTypes.MethodTy);
   values.addInt(ObjCTypes.IntTy, Size);
   // method_count
   values.addInt(ObjCTypes.IntTy, methods.size());
   auto methodArray = values.beginArray(ObjCTypes.MethodTy);
-  for (auto MD : methods) {
+  for (auto MD : methods)
     emitMethodConstant(methodArray, MD, forProtocol);
-  }
   methodArray.finishAndAddTo(values);
 
   llvm::GlobalVariable *GV = finishAndCreateGlobal(values, prefix + name, CGM);
   CGM.addCompilerUsedGlobal(GV);
   return llvm::ConstantExpr::getBitCast(GV, ObjCTypes.MethodListnfABIPtrTy);
 }
 
 /// ObjCIvarOffsetVariable - Returns the ivar offset variable for
 /// the given ivar.

clang/lib/CodeGen/CodeGenFunction.cpp

 static llvm::Constant *getPrologueSignature(CodeGenModule &CGM,
                                             const FunctionDecl *FD) {
   if (const auto *MD = dyn_cast<CXXMethodDecl>(FD))
     if (!MD->isStatic())
       return nullptr;
   return CGM.getTargetCodeGenInfo().getUBSanFunctionSignature(CGM);
 }
 
-void CodeGenFunction::StartFunction(GlobalDecl GD,
-                                    QualType RetTy,
+void CodeGenFunction::StartFunction(GlobalDecl GD, QualType RetTy,
                                     llvm::Function *Fn,
                                     const CGFunctionInfo &FnInfo,
                                     const FunctionArgList &Args,
                                     SourceLocation Loc,
                                     SourceLocation StartLoc) {
   assert(!CurFn &&
          "Do not use a CodeGenFunction object for more than one function");
 
   const Decl *D = GD.getDecl();

clang/lib/CodeGen/CodeGenModule.cpp

for (const auto *PID : D->property_impls()) {
     if (PID->getPropertyImplementation() == ObjCPropertyImplDecl::Synthesize) {
       ObjCPropertyDecl *PD = PID->getPropertyDecl();
 
       // Determine which methods need to be implemented, some may have
       // been overridden. Note that ::isPropertyAccessor is not the method
       // we want, that just indicates if the decl came from a
       // property. What we want to know is if the method is defined in
       // this implementation.
-      if (!D->getInstanceMethod(PD->getGetterName()))
+      auto *Getter = PID->getGetterMethodDecl();
+      if (!Getter || Getter->isSynthesizedAccessorStub())
         CodeGenFunction(*this).GenerateObjCGetter(
-                                 const_cast<ObjCImplementationDecl *>(D), PID);
-      if (!PD->isReadOnly() &&
-          !D->getInstanceMethod(PD->getSetterName()))
+      auto *Setter = PID->getSetterMethodDecl();
+      if (!PD->isReadOnly() && (!Setter || Setter->isSynthesizedAccessorStub()))
         CodeGenFunction(*this).GenerateObjCSetter(
                                  const_cast<ObjCImplementationDecl *>(D), PID);
     }
   }
 }
 
 static bool needsDestructMethod(ObjCImplementationDecl *impl) {
   const ObjCInterfaceDecl *iface = impl->getClassInterface();
   for (const ObjCIvarDecl *ivar = iface->all_declared_ivar_begin();
        ivar; ivar = ivar->getNextIvar())
     if (ivar->getType().isDestructedType())

 
 /// EmitObjCIvarInitializations - Emit information for ivar initialization
 /// for an implementation.
 void CodeGenModule::EmitObjCIvarInitializations(ObjCImplementationDecl *D) {
   // We might need a .cxx_destruct even if we don't have any ivar initializers.
   if (needsDestructMethod(D)) {
     IdentifierInfo *II = &getContext().Idents.get(".cxx_destruct");
     Selector cxxSelector = getContext().Selectors.getSelector(0, &II);
-    ObjCMethodDecl *DTORMethod =
-      ObjCMethodDecl::Create(getContext(), D->getLocation(), D->getLocation(),
-                             cxxSelector, getContext().VoidTy, nullptr, D,
-                             /*isInstance=*/true, /*isVariadic=*/false,
-                          /*isPropertyAccessor=*/true, /*isImplicitlyDeclared=*/true,
-                             /*isDefined=*/false, ObjCMethodDecl::Required);
+    ObjCMethodDecl *DTORMethod = ObjCMethodDecl::Create(
+        getContext(), D->getLocation(), D->getLocation(), cxxSelector,
+        getContext().VoidTy, nullptr, D,
+        /*isPropertyAccessor=*/true, /*isSynthesizedAccessorStub=*/false,
+        /*isImplicitlyDeclared=*/true,
     D->addInstanceMethod(DTORMethod);
     CodeGenFunction(*this).GenerateObjCCtorDtorMethod(D, DTORMethod, false);
     D->setHasDestructors(true);
   }
 
   // If the implementation doesn't have any ivar initializers, we don't need
   // a .cxx_construct.
   if (D->getNumIvarInitializers() == 0 ||
       AllTrivialInitializers(*this, D))
     return;
 
   IdentifierInfo *II = &getContext().Idents.get(".cxx_construct");
   Selector cxxSelector = getContext().Selectors.getSelector(0, &II);
   // The constructor returns 'self'.
-  ObjCMethodDecl *CTORMethod = ObjCMethodDecl::Create(getContext(),
-                                                D->getLocation(),
-                                                D->getLocation(),
-                                                cxxSelector,
-                                                getContext().getObjCIdType(),
-                                                nullptr, D, /*isInstance=*/true,
-                                                /*isVariadic=*/false,
-                                                /*isPropertyAccessor=*/true,
-                                                /*isImplicitlyDeclared=*/true,
-                                                /*isDefined=*/false,
-                                                ObjCMethodDecl::Required);
+  ObjCMethodDecl *CTORMethod = ObjCMethodDecl::Create(
+      getContext(), D->getLocation(), D->getLocation(), cxxSelector,
+      getContext().getObjCIdType(), nullptr, D, /*isInstance=*/true,
+      /*isPropertyAccessor=*/true, /*isSynthesizedAccessorStub=*/false,
+      /*isDefined=*/false, ObjCMethodDecl::Required);
   D->addInstanceMethod(CTORMethod);
   CodeGenFunction(*this).GenerateObjCCtorDtorMethod(D, CTORMethod, true);
   D->setHasNonZeroConstructors(true);
 }
 
 // EmitLinkageSpec - Emit all declarations in a linkage spec.
 void CodeGenModule::EmitLinkageSpec(const LinkageSpecDecl *LSD) {
   if (LSD->getLanguage() != LinkageSpecDecl::lang_c &&

clang/lib/Frontend/Rewrite/RewriteModernObjC.cpp

RewriteModernObjC::getIvarAccessString(ObjCIvarDecl *D) {
   return S;
 }
 
 /// mustSynthesizeSetterGetterMethod - returns true if setter or getter has not
 /// been found in the class implementation. In this case, it must be synthesized.
 static bool mustSynthesizeSetterGetterMethod(ObjCImplementationDecl *IMP,
                                              ObjCPropertyDecl *PD,
                                              bool getter) {
-  return getter ? !IMP->getInstanceMethod(PD->getGetterName())
-                : !IMP->getInstanceMethod(PD->getSetterName());
-
+  auto *OMD = IMP->getInstanceMethod(getter ? PD->getGetterName()
+                                            : PD->getSetterName());
+  return !OMD || OMD->isSynthesizedAccessorStub();
 }
 
 void RewriteModernObjC::RewritePropertyImplDecl(ObjCPropertyImplDecl *PID,
                                           ObjCImplementationDecl *IMD,
                                           ObjCCategoryImplDecl *CID) {
   static bool objcGetPropertyDefined = false;
   static bool objcSetPropertyDefined = false;
   SourceLocation startGetterSetterLoc;
if (mustSynthesizeSetterGetterMethod(IMD, PD, true /*getter*/)) {
     std::string Getr;
     if (GenGetProperty && !objcGetPropertyDefined) {
       objcGetPropertyDefined = true;
       // FIXME. Is this attribute correct in all cases?
       Getr = "\nextern \"C\" __declspec(dllimport) "
             "id objc_getProperty(id, SEL, long, bool);\n";
     }
     RewriteObjCMethodDecl(OID->getContainingInterface(),
-                          PD->getGetterMethodDecl(), Getr);
+                          PID->getGetterMethodDecl(), Getr);
     Getr += "{ ";
     // Synthesize an explicit cast to gain access to the ivar.
     // See objc-act.c:objc_synthesize_new_getter() for details.
     if (GenGetProperty) {
       // return objc_getProperty(self, _cmd, offsetof(ClassDecl, OID), 1)
       Getr += "typedef ";
       const FunctionType *FPRetType = nullptr;
-      RewriteTypeIntoString(PD->getGetterMethodDecl()->getReturnType(), Getr,
+      RewriteTypeIntoString(PID->getGetterMethodDecl()->getReturnType(), Getr,
                             FPRetType);
       Getr += " _TYPE";
       if (FPRetType) {
         Getr += ")"; // close the precedence "scope" for "*".
 
         // Now, emit the argument types (if any).
         if (const FunctionProtoType *FT = dyn_cast<FunctionProtoType>(FPRetType)){
           Getr += "(";
void RewriteModernObjC::RewritePropertyImplDecl(ObjCPropertyImplDecl *PID,
   if (GenSetProperty && !objcSetPropertyDefined) {
     objcSetPropertyDefined = true;
     // FIXME. Is this attribute correct in all cases?
     Setr = "\nextern \"C\" __declspec(dllimport) "
     "void objc_setProperty (id, SEL, long, id, bool, bool);\n";
   }
 
   RewriteObjCMethodDecl(OID->getContainingInterface(),
-                        PD->getSetterMethodDecl(), Setr);
+                        PID->getSetterMethodDecl(), Setr);
   Setr += "{ ";
   // Synthesize an explicit cast to initialize the ivar.
   // See objc-act.c:objc_synthesize_new_setter() for details.
   if (GenSetProperty) {
     Setr += "objc_setProperty (self, _cmd, ";
     RewriteIvarOffsetComputation(OID, Setr);
     Setr += ", (id)";
     Setr += PD->getName();
if (IMD) {
     else {
       InsertText(IMD->getBeginLoc(), "// ");
     }
   }
   else
     InsertText(CID->getBeginLoc(), "// ");
 
   for (auto *OMD : IMD ? IMD->instance_methods() : CID->instance_methods()) {
+    if (!OMD->getBody())
+      continue;
     std::string ResultStr;
     RewriteObjCMethodDecl(OMD->getClassInterface(), OMD, ResultStr);
     SourceLocation LocStart = OMD->getBeginLoc();
     SourceLocation LocEnd = OMD->getCompoundBody()->getBeginLoc();
 
     const char *startBuf = SM->getCharacterData(LocStart);
     const char *endBuf = SM->getCharacterData(LocEnd);
     ReplaceText(LocStart, endBuf-startBuf, ResultStr);
   }
 
   for (auto *OMD : IMD ? IMD->class_methods() : CID->class_methods()) {
+    if (!OMD->getBody())
+      continue;
     std::string ResultStr;
     RewriteObjCMethodDecl(OMD->getClassInterface(), OMD, ResultStr);
     SourceLocation LocStart = OMD->getBeginLoc();
     SourceLocation LocEnd = OMD->getCompoundBody()->getBeginLoc();
 
     const char *startBuf = SM->getCharacterData(LocStart);
     const char *endBuf = SM->getCharacterData(LocEnd);
     ReplaceText(LocStart, endBuf-startBuf, ResultStr);
void RewriteModernObjC::RewriteObjCClassMetaData(ObjCImplementationDecl *IDecl,
   for (const auto *Prop : IDecl->property_impls()) {
     if (Prop->getPropertyImplementation() == ObjCPropertyImplDecl::Dynamic)
       continue;
     if (!Prop->getPropertyIvarDecl())
       continue;
     ObjCPropertyDecl *PD = Prop->getPropertyDecl();
     if (!PD)
       continue;
-    if (ObjCMethodDecl *Getter = PD->getGetterMethodDecl())
+    if (ObjCMethodDecl *Getter = Prop->getGetterMethodDecl())
       if (mustSynthesizeSetterGetterMethod(IDecl, PD, true /*getter*/))
         InstanceMethods.push_back(Getter);
     if (PD->isReadOnly())
       continue;
-    if (ObjCMethodDecl *Setter = PD->getSetterMethodDecl())
+    if (ObjCMethodDecl *Setter = Prop->getSetterMethodDecl())
       if (mustSynthesizeSetterGetterMethod(IDecl, PD, false /*setter*/))
         InstanceMethods.push_back(Setter);
   }
 
   Write_method_list_t_initializer(*this, Context, Result, InstanceMethods,
                                   "_OBJC_$_INSTANCE_METHODS_",
                                   IDecl->getNameAsString(), true);
 
void RewriteModernObjC::RewriteObjCCategoryImplDecl(ObjCCategoryImplDecl *IDecl,
   for (const auto *Prop : IDecl->property_impls()) {
     if (Prop->getPropertyImplementation() == ObjCPropertyImplDecl::Dynamic)
       continue;
     if (!Prop->getPropertyIvarDecl())
       continue;
     ObjCPropertyDecl *PD = Prop->getPropertyDecl();
     if (!PD)
       continue;
-    if (ObjCMethodDecl *Getter = PD->getGetterMethodDecl())
+    if (ObjCMethodDecl *Getter = Prop->getGetterMethodDecl())
       InstanceMethods.push_back(Getter);
     if (PD->isReadOnly())
       continue;
-    if (ObjCMethodDecl *Setter = PD->getSetterMethodDecl())
+    if (ObjCMethodDecl *Setter = Prop->getSetterMethodDecl())
       InstanceMethods.push_back(Setter);
   }
 
   Write_method_list_t_initializer(*this, Context, Result, InstanceMethods,
                                   "_OBJC_$_CATEGORY_INSTANCE_METHODS_",
                                   FullCategoryName, true);
 
   SmallVector<ObjCMethodDecl *, 32> ClassMethods(IDecl->class_methods());

clang/lib/Frontend/Rewrite/RewriteObjC.cpp

if (PID->getPropertyImplementation() == ObjCPropertyImplDecl::Dynamic)
     return; // FIXME: is this correct?
 
   // Generate the 'getter' function.
   ObjCPropertyDecl *PD = PID->getPropertyDecl();
   ObjCIvarDecl *OID = PID->getPropertyIvarDecl();
 
   if (!OID)
     return;
+
   unsigned Attributes = PD->getPropertyAttributes();
-  if (!PD->getGetterMethodDecl()->isDefined()) {
+  if (PID->getGetterMethodDecl() && !PID->getGetterMethodDecl()->isDefined()) {
     bool GenGetProperty = !(Attributes & ObjCPropertyDecl::OBJC_PR_nonatomic) &&
                           (Attributes & (ObjCPropertyDecl::OBJC_PR_retain |
                                          ObjCPropertyDecl::OBJC_PR_copy));
     std::string Getr;
     if (GenGetProperty && !objcGetPropertyDefined) {
       objcGetPropertyDefined = true;
       // FIXME. Is this attribute correct in all cases?
       Getr = "\nextern \"C\" __declspec(dllimport) "
             "id objc_getProperty(id, SEL, long, bool);\n";
     }
     RewriteObjCMethodDecl(OID->getContainingInterface(),
-                          PD->getGetterMethodDecl(), Getr);
+                          PID->getGetterMethodDecl(), Getr);
     Getr += "{ ";
     // Synthesize an explicit cast to gain access to the ivar.
     // See objc-act.c:objc_synthesize_new_getter() for details.
     if (GenGetProperty) {
       // return objc_getProperty(self, _cmd, offsetof(ClassDecl, OID), 1)
       Getr += "typedef ";
       const FunctionType *FPRetType = nullptr;
-      RewriteTypeIntoString(PD->getGetterMethodDecl()->getReturnType(), Getr,
+      RewriteTypeIntoString(PID->getGetterMethodDecl()->getReturnType(), Getr,
                             FPRetType);
       Getr += " _TYPE";
       if (FPRetType) {
         Getr += ")"; // close the precedence "scope" for "*".
 
         // Now, emit the argument types (if any).
         if (const FunctionProtoType *FT = dyn_cast<FunctionProtoType>(FPRetType)){
           Getr += "(";
if (GenGetProperty) {
       Getr += ", 1)";
     }
     else
       Getr += "return " + getIvarAccessString(OID);
     Getr += "; }";
     InsertText(onePastSemiLoc, Getr);
   }
 
-  if (PD->isReadOnly() || PD->getSetterMethodDecl()->isDefined())
+  if (PD->isReadOnly() || !PID->getSetterMethodDecl() ||
+      PID->getSetterMethodDecl()->isDefined())
     return;
 
   // Generate the 'setter' function.
   std::string Setr;
   bool GenSetProperty = Attributes & (ObjCPropertyDecl::OBJC_PR_retain |
                                       ObjCPropertyDecl::OBJC_PR_copy);
   if (GenSetProperty && !objcSetPropertyDefined) {
     objcSetPropertyDefined = true;
     // FIXME. Is this attribute correct in all cases?
     Setr = "\nextern \"C\" __declspec(dllimport) "
     "void objc_setProperty (id, SEL, long, id, bool, bool);\n";
   }
 
   RewriteObjCMethodDecl(OID->getContainingInterface(),
-                        PD->getSetterMethodDecl(), Setr);
+                        PID->getSetterMethodDecl(), Setr);
   Setr += "{ ";
   // Synthesize an explicit cast to initialize the ivar.
   // See objc-act.c:objc_synthesize_new_setter() for details.
   if (GenSetProperty) {
     Setr += "objc_setProperty (self, _cmd, ";
     RewriteIvarOffsetComputation(OID, Setr);
     Setr += ", (id)";
     Setr += PD->getName();

 void RewriteObjC::RewriteImplementationDecl(Decl *OID) {
   ObjCImplementationDecl *IMD = dyn_cast<ObjCImplementationDecl>(OID);
   ObjCCategoryImplDecl *CID = dyn_cast<ObjCCategoryImplDecl>(OID);
   assert((IMD || CID) && "Unknown ImplementationDecl");
 
   InsertText(IMD ? IMD->getBeginLoc() : CID->getBeginLoc(), "// ");
 
   for (auto *OMD : IMD ? IMD->instance_methods() : CID->instance_methods()) {
+    if (!OMD->getBody())
+      continue;
     std::string ResultStr;
     RewriteObjCMethodDecl(OMD->getClassInterface(), OMD, ResultStr);
     SourceLocation LocStart = OMD->getBeginLoc();
     SourceLocation LocEnd = OMD->getCompoundBody()->getBeginLoc();
 
     const char *startBuf = SM->getCharacterData(LocStart);
     const char *endBuf = SM->getCharacterData(LocEnd);
     ReplaceText(LocStart, endBuf-startBuf, ResultStr);
   }
 
   for (auto *OMD : IMD ? IMD->class_methods() : CID->class_methods()) {
+    if (!OMD->getBody())
+      continue;
     std::string ResultStr;
     RewriteObjCMethodDecl(OMD->getClassInterface(), OMD, ResultStr);
     SourceLocation LocStart = OMD->getBeginLoc();
     SourceLocation LocEnd = OMD->getCompoundBody()->getBeginLoc();
 
     const char *startBuf = SM->getCharacterData(LocStart);
     const char *endBuf = SM->getCharacterData(LocEnd);
     ReplaceText(LocStart, endBuf-startBuf, ResultStr);
void RewriteObjCFragileABI::RewriteObjCClassMetaData(ObjCImplementationDecl *IDecl,
   for (const auto *Prop : IDecl->property_impls()) {
     if (Prop->getPropertyImplementation() == ObjCPropertyImplDecl::Dynamic)
       continue;
     if (!Prop->getPropertyIvarDecl())
       continue;
     ObjCPropertyDecl *PD = Prop->getPropertyDecl();
     if (!PD)
       continue;
-    if (ObjCMethodDecl *Getter = PD->getGetterMethodDecl())
+    if (ObjCMethodDecl *Getter = Prop->getGetterMethodDecl())
       if (!Getter->isDefined())
         InstanceMethods.push_back(Getter);
     if (PD->isReadOnly())
       continue;
-    if (ObjCMethodDecl *Setter = PD->getSetterMethodDecl())
+    if (ObjCMethodDecl *Setter = Prop->getSetterMethodDecl())
       if (!Setter->isDefined())
         InstanceMethods.push_back(Setter);
   }
   RewriteObjCMethodsMetaData(InstanceMethods.begin(), InstanceMethods.end(),
                              true, "", IDecl->getName(), Result);
 
   // Build _objc_method_list for class's class methods if needed
   RewriteObjCMethodsMetaData(IDecl->classmeth_begin(), IDecl->classmeth_end(),
void RewriteObjCFragileABI::RewriteObjCCategoryImplDecl(ObjCCategoryImplDecl *IDecl,
   for (const auto *Prop : IDecl->property_impls()) {
     if (Prop->getPropertyImplementation() == ObjCPropertyImplDecl::Dynamic)
       continue;
     if (!Prop->getPropertyIvarDecl())
       continue;
     ObjCPropertyDecl *PD = Prop->getPropertyDecl();
     if (!PD)
       continue;
-    if (ObjCMethodDecl *Getter = PD->getGetterMethodDecl())
+    if (ObjCMethodDecl *Getter = Prop->getGetterMethodDecl())
       InstanceMethods.push_back(Getter);
     if (PD->isReadOnly())
       continue;
-    if (ObjCMethodDecl *Setter = PD->getSetterMethodDecl())
+    if (ObjCMethodDecl *Setter = Prop->getSetterMethodDecl())
       InstanceMethods.push_back(Setter);
   }
   RewriteObjCMethodsMetaData(InstanceMethods.begin(), InstanceMethods.end(),
                              true, "CATEGORY_", FullCategoryName, Result);
 
   // Build _objc_method_list for class's class methods if needed
   RewriteObjCMethodsMetaData(IDecl->classmeth_begin(), IDecl->classmeth_end(),
                              false, "CATEGORY_", FullCategoryName, Result);

clang/lib/Index/IndexDecl.cpp

public:
 
   bool Handled = true;
 
   bool VisitDecl(const Decl *D) {
     Handled = false;
     return true;
   }
 
-  /// Returns true if the given method has been defined explicitly by the
-  /// user.
-  static bool hasUserDefined(const ObjCMethodDecl *D,
-                             const ObjCImplDecl *Container) {
-    const ObjCMethodDecl *MD = Container->getMethod(D->getSelector(),
-                                                    D->isInstanceMethod());
-    return MD && !MD->isImplicit() && MD->isThisDeclarationADefinition();
-  }
-
   void handleTemplateArgumentLoc(const TemplateArgumentLoc &TALoc,
                                  const NamedDecl *Parent,
                                  const DeclContext *DC) {
     const TemplateArgumentLocInfo &LocInfo = TALoc.getLocInfo();
     switch (TALoc.getArgument().getKind()) {
     case TemplateArgument::Expression:
       IndexCtx.indexBody(LocInfo.getAsExpr(), Parent, DC);
       break;
case TemplateArgument::TemplateExpansion:
           IndexCtx.handleReference(TTD, TALoc.getTemplateNameLoc(), Parent, DC);
       }
       break;
     default:
       break;
     }
   }
 
+  /// Returns true if the given method has been defined explicitly by the
+  /// user.
+  static bool hasUserDefined(const ObjCMethodDecl *D,
+                             const ObjCImplDecl *Container) {
+    const ObjCMethodDecl *MD = Container->getMethod(D->getSelector(),
+                                                    D->isInstanceMethod());
+    return MD && !MD->isImplicit() && MD->isThisDeclarationADefinition() &&
+           !MD->isSynthesizedAccessorStub();
+  }
+
+  
   void handleDeclarator(const DeclaratorDecl *D,
                         const NamedDecl *Parent = nullptr,
                         bool isIBType = false) {
     if (!Parent) Parent = D;
 
     IndexCtx.indexTypeSourceInfo(D->getTypeSourceInfo(), Parent,
                                  Parent->getLexicalDeclContext(),
                                  /*isBase=*/false, isIBType);
bool VisitObjCPropertyImplDecl(const ObjCPropertyImplDecl *D) {
 
     if (D->getPropertyImplementation() == ObjCPropertyImplDecl::Dynamic)
       return true;
 
     assert(D->getPropertyImplementation() == ObjCPropertyImplDecl::Synthesize);
     SymbolRoleSet AccessorMethodRoles =
       SymbolRoleSet(SymbolRole::Dynamic) | SymbolRoleSet(SymbolRole::Implicit);
     if (ObjCMethodDecl *MD = PD->getGetterMethodDecl()) {
-      if (MD->isPropertyAccessor() &&
-          !hasUserDefined(MD, Container))
+      if (MD->isPropertyAccessor() && !hasUserDefined(MD, Container))
         IndexCtx.handleDecl(MD, Loc, AccessorMethodRoles, {}, Container);
     }
     if (ObjCMethodDecl *MD = PD->getSetterMethodDecl()) {
-      if (MD->isPropertyAccessor() &&
-          !hasUserDefined(MD, Container))
+      if (MD->isPropertyAccessor() && !hasUserDefined(MD, Container))
         IndexCtx.handleDecl(MD, Loc, AccessorMethodRoles, {}, Container);
     }
     if (ObjCIvarDecl *IvarD = D->getPropertyIvarDecl()) {
       if (IvarD->getSynthesize()) {
         // For synthesized ivars, use the location of its name in the
         // corresponding @synthesize. If there isn't one, use the containing
         // @implementation's location, rather than the property's location,
         // otherwise the header file containing the @interface will have different

clang/lib/Sema/SemaDeclObjC.cpp

if (!I->isPropertyAccessor() &&
       continue;
     } else {
       ObjCMethodDecl *ImpMethodDecl =
         IMPDecl->getInstanceMethod(I->getSelector());
       assert(CDecl->getInstanceMethod(I->getSelector(), true/*AllowHidden*/) &&
              "Expected to find the method through lookup as well");
       // ImpMethodDecl may be null as in a @dynamic property.
       if (ImpMethodDecl) {
+        // Skip property accessor function stubs.
+        if (ImpMethodDecl->isSynthesizedAccessorStub())
+          continue;
         if (!WarnCategoryMethodImpl)
           WarnConflictingTypedMethods(ImpMethodDecl, I,
                                       isa<ObjCProtocolDecl>(CDecl));
         else if (!I->isPropertyAccessor())
           WarnExactTypedMethods(ImpMethodDecl, I, isa<ObjCProtocolDecl>(CDecl));
       }
     }
   }
if (!I->isPropertyAccessor() &&
                             diag::warn_undef_method_impl);
     } else {
       ObjCMethodDecl *ImpMethodDecl =
         IMPDecl->getClassMethod(I->getSelector());
       assert(CDecl->getClassMethod(I->getSelector(), true/*AllowHidden*/) &&
              "Expected to find the method through lookup as well");
       // ImpMethodDecl may be null as in a @dynamic property.
       if (ImpMethodDecl) {
+        // Skip property accessor function stubs.
+        if (ImpMethodDecl->isSynthesizedAccessorStub())
+          continue;
         if (!WarnCategoryMethodImpl)
           WarnConflictingTypedMethods(ImpMethodDecl, I,
                                       isa<ObjCProtocolDecl>(CDecl));
         else if (!I->isPropertyAccessor())
           WarnExactTypedMethods(ImpMethodDecl, I, isa<ObjCProtocolDecl>(CDecl));
       }
     }
   }
Decl *Sema::ActOnAtEnd(Scope *S, SourceRange AtEnd, ArrayRef<Decl *> allMethods,
   auto *OCD = cast<ObjCContainerDecl>(CurContext);
   Decl *ClassDecl = OCD;
 
   bool isInterfaceDeclKind =
         isa<ObjCInterfaceDecl>(ClassDecl) || isa<ObjCCategoryDecl>(ClassDecl)
          || isa<ObjCProtocolDecl>(ClassDecl);
   bool checkIdenticalMethods = isa<ObjCImplementationDecl>(ClassDecl);
 
+  // Make synthesized accessor stub functions visible.
+  // ActOnPropertyImplDecl() creates them as not visible in case
+  // they are overridden by an explicit method that is encountered
+  // later.
+  if (auto *OID = dyn_cast<ObjCImplementationDecl>(CurContext)) {
+    for (auto PropImpl : OID->property_impls()) {
+      if (auto *Getter = PropImpl->getGetterMethodDecl())
+        if (Getter->isSynthesizedAccessorStub()) {
+          OID->makeDeclVisibleInContext(Getter);
+          OID->addDecl(Getter);
+        }
+      if (auto *Setter = PropImpl->getSetterMethodDecl())
+        if (Setter->isSynthesizedAccessorStub()) {
+          OID->makeDeclVisibleInContext(Setter);
+          OID->addDecl(Setter);
+        }
+    }
+  }
+
   // FIXME: Remove these and use the ObjCContainerDecl/DeclContext.
   llvm::DenseMap<Selector, const ObjCMethodDecl*> InsMap;
   llvm::DenseMap<Selector, const ObjCMethodDecl*> ClsMap;
 
   for (unsigned i = 0, e = allMethods.size(); i != e; i++ ) {
     ObjCMethodDecl *Method =
       cast_or_null<ObjCMethodDecl>(allMethods[i]);
 
if (ObjCInterfaceDecl* IDecl = IC->getClassInterface()) {
           if (const ObjCPropertyImplDecl *PIDecl
               = IC->FindPropertyImplDecl(Property->getIdentifier(),
                                          Property->getQueryKind()))
             if (PIDecl->getPropertyImplementation()
                   == ObjCPropertyImplDecl::Dynamic)
               continue;
 
           for (const auto *Ext : IDecl->visible_extensions()) {
-            if (ObjCMethodDecl *GetterMethod
-                  = Ext->getInstanceMethod(Property->getGetterName()))
+            if (ObjCMethodDecl *GetterMethod =
+                    Ext->getInstanceMethod(Property->getGetterName()))
               GetterMethod->setPropertyAccessor(true);
             if (!Property->isReadOnly())
               if (ObjCMethodDecl *SetterMethod
                     = Ext->getInstanceMethod(Property->getSetterName()))
                 SetterMethod->setPropertyAccessor(true);
           }
         }
       }
Decl *Sema::ActOnMethodDeclaration(
     unsigned CNumArgs, // c-style args
     const ParsedAttributesView &AttrList, tok::ObjCKeywordKind MethodDeclKind,
     bool isVariadic, bool MethodDefinition) {
   // Make sure we can establish a context for the method.
   if (!CurContext->isObjCContainer()) {
     Diag(MethodLoc, diag::err_missing_method_context);
     return nullptr;
   }
+
   Decl *ClassDecl = cast<ObjCContainerDecl>(CurContext);
   QualType resultDeclType;
 
   bool HasRelatedResultType = false;
   TypeSourceInfo *ReturnTInfo = nullptr;
   if (ReturnType) {
     resultDeclType = GetTypeFromParser(ReturnType, &ReturnTInfo);
 
     if (CheckFunctionReturnType(resultDeclType, MethodLoc))
       return nullptr;
 
     QualType bareResultType = resultDeclType;
     (void)AttributedType::stripOuterNullability(bareResultType);
     HasRelatedResultType = (bareResultType == Context.getObjCInstanceType());
   } else { // get the type for "id".
     resultDeclType = Context.getObjCIdType();
     Diag(MethodLoc, diag::warn_missing_method_return_type)
       << FixItHint::CreateInsertion(SelectorLocs.front(), "(id)");
   }
 
   ObjCMethodDecl *ObjCMethod = ObjCMethodDecl::Create(
       Context, MethodLoc, EndLoc, Sel, resultDeclType, ReturnTInfo, CurContext,
       MethodType == tok::minus, isVariadic,
-      /*isPropertyAccessor=*/false,
+      /*isPropertyAccessor=*/false, /*isSynthesizedAccessorStub=*/false,
       /*isImplicitlyDeclared=*/false, /*isDefined=*/false,
       MethodDeclKind == tok::objc_optional ? ObjCMethodDecl::Optional
                                            : ObjCMethodDecl::Required,
       HasRelatedResultType);
 
   SmallVector<ParmVarDecl*, 16> Params;
 
   for (unsigned i = 0, e = Sel.getNumArgs(); i != e; ++i) {
if (ObjCImplDecl *ImpDecl = dyn_cast<ObjCImplDecl>(ClassDecl)) {
     if (MethodType == tok::minus) {
       PrevMethod = ImpDecl->getInstanceMethod(Sel);
       ImpDecl->addInstanceMethod(ObjCMethod);
     } else {
       PrevMethod = ImpDecl->getClassMethod(Sel);
       ImpDecl->addClassMethod(ObjCMethod);
     }
 
+    // If this method overrides a previous @synthesize declaration,
+    // register it with the property.  Linear search through all
+    // properties here, because the autosynthesized stub hasn't been
+    // made visible yet, so it can be overriden by a later
+    // user-specified implementation.
+    for (ObjCPropertyImplDecl *PropertyImpl : ImpDecl->property_impls()) {
+      if (auto *Setter = PropertyImpl->getSetterMethodDecl())
+        if (Setter->getSelector() == Sel &&
+            Setter->isInstanceMethod() == ObjCMethod->isInstanceMethod()) {
+          assert(Setter->isSynthesizedAccessorStub() && "autosynth stub expected");
+          PropertyImpl->setSetterMethodDecl(ObjCMethod);
+        }
+      if (auto *Getter = PropertyImpl->getGetterMethodDecl())
+        if (Getter->getSelector() == Sel &&
+            Getter->isInstanceMethod() == ObjCMethod->isInstanceMethod()) {
+          assert(Getter->isSynthesizedAccessorStub() && "autosynth stub expected");
+          PropertyImpl->setGetterMethodDecl(ObjCMethod);
+          break;
+        }
+    }
+
     // Merge information from the @interface declaration into the
     // @implementation.
     if (ObjCInterfaceDecl *IDecl = ImpDecl->getClassInterface()) {
       if (auto *IMD = IDecl->lookupMethod(ObjCMethod->getSelector(),
                                           ObjCMethod->isInstanceMethod())) {
         mergeInterfaceMethodToImpl(*this, ObjCMethod, IMD);
 
         // Warn about defining -dealloc in a category.
for (const auto *CurMethod : ImplD->instance_methods()) {
     if (Diags.isIgnored(DIAG, Loc))
       continue;
 
     const ObjCPropertyDecl *PDecl;
     const ObjCIvarDecl *IV = GetIvarBackingPropertyAccessor(CurMethod, PDecl);
     if (!IV)
       continue;
 
+    if (CurMethod->isSynthesizedAccessorStub())
+      continue;
+
     UnusedBackingIvarChecker Checker(*this, CurMethod, IV);
     Checker.TraverseStmt(CurMethod->getBody());
     if (Checker.AccessedIvar)
       continue;
 
     // Do not issue this warning if backing ivar is used somewhere and accessor
     // implementation makes a self call. This is to prevent false positive in
     // cases where the ivar is accessed by another method that the accessor
     // delegates to.
     if (!IV->isReferenced() || !Checker.InvokedSelfMethod) {
       Diag(Loc, DIAG) << IV;
       Diag(PDecl->getLocation(), diag::note_property_declare);
     }
   }
 }

clang/lib/Sema/SemaExprObjC.cpp

static ObjCMethodDecl *getNSNumberFactoryMethod(Sema &S, SourceLocation Loc,
   if (!Method && S.getLangOpts().DebuggerObjCLiteral) {
     // create a stub definition this NSNumber factory method.
     TypeSourceInfo *ReturnTInfo = nullptr;
     Method =
         ObjCMethodDecl::Create(CX, SourceLocation(), SourceLocation(), Sel,
                                S.NSNumberPointer, ReturnTInfo, S.NSNumberDecl,
                                /*isInstance=*/false, /*isVariadic=*/false,
                                /*isPropertyAccessor=*/false,
+                               /*isSynthesizedAccessorStub=*/false,
                                /*isImplicitlyDeclared=*/true,
                                /*isDefined=*/false, ObjCMethodDecl::Required,
                                /*HasRelatedResultType=*/false);
     ParmVarDecl *value = ParmVarDecl::Create(S.Context, Method,
                                              SourceLocation(), SourceLocation(),
                                              &CX.Idents.get("value"),
                                              NumberType, /*TInfo=*/nullptr,
                                              SC_None, nullptr);
if (Context.hasSameUnqualifiedType(PointeeType, Context.CharTy)) {
         if (!BoxingMethod && getLangOpts().DebuggerObjCLiteral) {
           // Debugger needs to work even if NSString hasn't been defined.
           TypeSourceInfo *ReturnTInfo = nullptr;
           ObjCMethodDecl *M = ObjCMethodDecl::Create(
               Context, SourceLocation(), SourceLocation(), stringWithUTF8String,
               NSStringPointer, ReturnTInfo, NSStringDecl,
               /*isInstance=*/false, /*isVariadic=*/false,
               /*isPropertyAccessor=*/false,
+              /*isSynthesizedAccessorStub=*/false,
               /*isImplicitlyDeclared=*/true,
               /*isDefined=*/false, ObjCMethodDecl::Required,
               /*HasRelatedResultType=*/false);
           QualType ConstCharType = Context.CharTy.withConst();
           ParmVarDecl *value =
             ParmVarDecl::Create(Context, M,
                                 SourceLocation(), SourceLocation(),
                                 &Context.Idents.get("value"),
if (!ValueWithBytesObjCTypeMethod) {
       Selector ValueWithBytesObjCType = Context.Selectors.getSelector(2, II);
 
       // Look for the appropriate method within NSValue.
       BoxingMethod = NSValueDecl->lookupClassMethod(ValueWithBytesObjCType);
       if (!BoxingMethod && getLangOpts().DebuggerObjCLiteral) {
         // Debugger needs to work even if NSValue hasn't been defined.
         TypeSourceInfo *ReturnTInfo = nullptr;
         ObjCMethodDecl *M = ObjCMethodDecl::Create(
-                                               Context,
-                                               SourceLocation(),
-                                               SourceLocation(),
-                                               ValueWithBytesObjCType,
-                                               NSValuePointer,
-                                               ReturnTInfo,
-                                               NSValueDecl,
-                                               /*isInstance=*/false,
-                                               /*isVariadic=*/false,
-                                               /*isPropertyAccessor=*/false,
-                                               /*isImplicitlyDeclared=*/true,
-                                               /*isDefined=*/false,
-                                               ObjCMethodDecl::Required,
-                                               /*HasRelatedResultType=*/false);
+            Context, SourceLocation(), SourceLocation(), ValueWithBytesObjCType,
+            NSValuePointer, ReturnTInfo, NSValueDecl,
+            /*isSynthesizedAccessorStub=*/false,
+            /*isDefined=*/false, ObjCMethodDecl::Required,
 
         SmallVector<ParmVarDecl *, 2> Params;
 
         ParmVarDecl *bytes =
         ParmVarDecl::Create(Context, M,
                             SourceLocation(), SourceLocation(),
                             &Context.Idents.get("bytes"),
                             Context.VoidPtrTy.withConst(),
Selector
       Sel = NSAPIObj->getNSArraySelector(NSAPI::NSArr_arrayWithObjectsCount);
     ObjCMethodDecl *Method = NSArrayDecl->lookupClassMethod(Sel);
     if (!Method && getLangOpts().DebuggerObjCLiteral) {
       TypeSourceInfo *ReturnTInfo = nullptr;
       Method = ObjCMethodDecl::Create(
           Context, SourceLocation(), SourceLocation(), Sel, IdT, ReturnTInfo,
           Context.getTranslationUnitDecl(), false /*Instance*/,
           false /*isVariadic*/,
-          /*isPropertyAccessor=*/false,
+          /*isPropertyAccessor=*/false, /*isSynthesizedAccessorStub=*/false,
           /*isImplicitlyDeclared=*/true, /*isDefined=*/false,
           ObjCMethodDecl::Required, false);
       SmallVector<ParmVarDecl *, 2> Params;
       ParmVarDecl *objects = ParmVarDecl::Create(Context, Method,
                                                  SourceLocation(),
                                                  SourceLocation(),
                                                  &Context.Idents.get("objects"),
                                                  Context.getPointerType(IdT),
ExprResult Sema::BuildObjCDictionaryLiteral(SourceRange SR,
   // Find the dictionaryWithObjects:forKeys:count: method, if we haven't done
   // so already.
   QualType IdT = Context.getObjCIdType();
   if (!DictionaryWithObjectsMethod) {
     Selector Sel = NSAPIObj->getNSDictionarySelector(
                                NSAPI::NSDict_dictionaryWithObjectsForKeysCount);
     ObjCMethodDecl *Method = NSDictionaryDecl->lookupClassMethod(Sel);
     if (!Method && getLangOpts().DebuggerObjCLiteral) {
-      Method = ObjCMethodDecl::Create(Context,
-                           SourceLocation(), SourceLocation(), Sel,
-                           IdT,
-                           nullptr /*TypeSourceInfo */,
-                           Context.getTranslationUnitDecl(),
-                           false /*Instance*/, false/*isVariadic*/,
-                           /*isPropertyAccessor=*/false,
-                           /*isImplicitlyDeclared=*/true, /*isDefined=*/false,
-                           ObjCMethodDecl::Required,
-                           false);
+      Method = ObjCMethodDecl::Create(
+          Context, SourceLocation(), SourceLocation(), Sel, IdT,
+          nullptr /*TypeSourceInfo */, Context.getTranslationUnitDecl(),
+          false /*Instance*/, false /*isVariadic*/,
+          /*isSynthesizedAccessorStub=*/false,
+          ObjCMethodDecl::Required, false);
       SmallVector<ParmVarDecl *, 3> Params;
       ParmVarDecl *objects = ParmVarDecl::Create(Context, Method,
                                                  SourceLocation(),
                                                  SourceLocation(),
                                                  &Context.Idents.get("objects"),
                                                  Context.getPointerType(IdT),
                                                  /*TInfo=*/nullptr, SC_None,
                                                  nullptr);

clang/lib/Sema/SemaObjCProperty.cpp

for (const auto *Proto : OrigClass->all_referenced_protocols()) {
     if (ObjCPropertyDecl *OrigProp = Proto->FindPropertyDeclaration(
             Prop->getIdentifier(), QueryKind))
       return OrigProp->getPropertyAttributesAsWritten() & OwnershipMask;
   }
 
   return false;
 }
 
+/// Create a synthesized property accessor stub inside the \@implementation.
+static ObjCMethodDecl *
+RedeclarePropertyAccessor(ASTContext &Context, ObjCImplementationDecl *Impl,
+                          ObjCMethodDecl *AccessorDecl, SourceLocation AtLoc,
+                          SourceLocation PropertyLoc) {
+  ObjCMethodDecl *Decl = AccessorDecl;
+  ObjCMethodDecl *ImplDecl = ObjCMethodDecl::Create(
+      Context, AtLoc, PropertyLoc, Decl->getSelector(), Decl->getReturnType(),
+      Decl->getReturnTypeSourceInfo(), Impl, Decl->isInstanceMethod(),
+      Decl->isVariadic(), Decl->isPropertyAccessor(), /* isSynthesized*/ true,
+      Decl->isImplicit(), Decl->isDefined(), Decl->getImplementationControl(),
+      Decl->hasRelatedResultType());
+  ImplDecl->getMethodFamily();
+  if (Decl->hasAttrs())
+    ImplDecl->setAttrs(Decl->getAttrs());
+  ImplDecl->setSelfDecl(Decl->getSelfDecl());
+  ImplDecl->setCmdDecl(Decl->getCmdDecl());
+  SmallVector<SourceLocation, 1> SelLocs;
+  Decl->getSelectorLocs(SelLocs);
+  ImplDecl->setMethodParams(Context, Decl->parameters(), SelLocs);
+  ImplDecl->setLexicalDeclContext(Impl);
+  ImplDecl->setDefined(false);
+  return ImplDecl;
+}
+
 /// ActOnPropertyImplDecl - This routine performs semantic checks and
 /// builds the AST node for a property implementation declaration; declared
 /// as \@synthesize or \@dynamic.
 ///
 Decl *Sema::ActOnPropertyImplDecl(Scope *S,
                                   SourceLocation AtLoc,
                                   SourceLocation PropertyLoc,
                                   bool Synthesize,
ObjCPropertyImplDecl::Create(Context, CurContext, AtLoc, PropertyLoc,
                                 : ObjCPropertyImplDecl::Dynamic),
                                Ivar, PropertyIvarLoc);
 
   if (CompleteTypeErr || !compat)
     PIDecl->setInvalidDecl();
 
   if (ObjCMethodDecl *getterMethod = property->getGetterMethodDecl()) {
     getterMethod->createImplicitParams(Context, IDecl);
+
+    // Redeclare the getter within the implementation as DeclContext.
+    if (Synthesize) {
+      // If the method hasn't been overridden, create a synthesized implementation.
+      ObjCMethodDecl *OMD = ClassImpDecl->getMethod(
+          getterMethod->getSelector(), getterMethod->isInstanceMethod());
+      if (!OMD)
+        OMD = RedeclarePropertyAccessor(Context, IC, getterMethod, AtLoc,
+                                        PropertyLoc);
+      PIDecl->setGetterMethodDecl(OMD);
+    }
+ 
     if (getLangOpts().CPlusPlus && Synthesize && !CompleteTypeErr &&
         Ivar->getType()->isRecordType()) {
       // For Objective-C++, need to synthesize the AST for the IVAR object to be
       // returned by the getter as it must conform to C++'s copy-return rules.
       // FIXME. Eventually we want to do this for Objective-C as well.
       SynthesizedFunctionScope Scope(*this, getterMethod);
       ImplicitParamDecl *SelfDecl = getterMethod->getSelfDecl();
       DeclRefExpr *SelfExpr = new (Context)
if (getLangOpts().ObjCAutoRefCount && Synthesize)
         case OMF_autorelease:
           Diag(getterMethod->getLocation(), diag::err_arc_illegal_method_def)
             << 1 << getterMethod->getSelector();
           break;
         default:
           break;
       }
   }
+
   if (ObjCMethodDecl *setterMethod = property->getSetterMethodDecl()) {
     setterMethod->createImplicitParams(Context, IDecl);
+
+    // Redeclare the setter within the implementation as DeclContext.
+    if (Synthesize) {
+      ObjCMethodDecl *OMD = ClassImpDecl->getMethod(
+          setterMethod->getSelector(), setterMethod->isInstanceMethod());
+      if (!OMD)
+        OMD = RedeclarePropertyAccessor(Context, IC, setterMethod,
+                                        AtLoc, PropertyLoc);
+      PIDecl->setSetterMethodDecl(OMD);
+    }
+
     if (getLangOpts().CPlusPlus && Synthesize && !CompleteTypeErr &&
         Ivar->getType()->isRecordType()) {
       // FIXME. Eventually we want to do this for Objective-C as well.
       SynthesizedFunctionScope Scope(*this, setterMethod);
       ImplicitParamDecl *SelfDecl = setterMethod->getSelfDecl();
       DeclRefExpr *SelfExpr = new (Context)
           DeclRefExpr(Context, SelfDecl, false, SelfDecl->getType(), VK_LValue,
                       PropertyDiagLoc);
for (unsigned i = 0, e = PropertyOrder.size(); i != e; i++) {
     if (Prop->isInvalidDecl() ||
         Prop->isClassProperty() ||
         Prop->getPropertyImplementation() == ObjCPropertyDecl::Optional)
       continue;
     // Property may have been synthesized by user.
     if (IMPDecl->FindPropertyImplDecl(
             Prop->getIdentifier(), Prop->getQueryKind()))
       continue;
-    if (IMPDecl->getInstanceMethod(Prop->getGetterName())) {
+    ObjCMethodDecl *ImpMethod = IMPDecl->getInstanceMethod(Prop->getGetterName());
+    if (ImpMethod && !ImpMethod->getBody()) {
       if (Prop->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_readonly)
         continue;
-      if (IMPDecl->getInstanceMethod(Prop->getSetterName()))
+      ImpMethod = IMPDecl->getInstanceMethod(Prop->getSetterName());
+      if (ImpMethod && !ImpMethod->getBody())
         continue;
     }
     if (ObjCPropertyImplDecl *PID =
         IMPDecl->FindPropertyImplIvarDecl(Prop->getIdentifier())) {
       Diag(Prop->getLocation(), diag::warn_no_autosynthesis_shared_ivar_property)
         << Prop->getIdentifier();
       if (PID->getLocation().isValid())
         Diag(PID->getLocation(), diag::note_property_synthesize);
if (!Prop->isReadOnly())
                                     PrimaryClass, Prop->getSetterName(),
                                     IMPDecl, CDecl, C, Prop, InsMap);
   }
 }
 
 void Sema::diagnoseNullResettableSynthesizedSetters(const ObjCImplDecl *impDecl) {
   for (const auto *propertyImpl : impDecl->property_impls()) {
     const auto *property = propertyImpl->getPropertyDecl();
-
     // Warn about null_resettable properties with synthesized setters,
     // because the setter won't properly handle nil.
     if (propertyImpl->getPropertyImplementation()
           == ObjCPropertyImplDecl::Synthesize &&
         (property->getPropertyAttributes() &
          ObjCPropertyDecl::OBJC_PR_null_resettable) &&
         property->getGetterMethodDecl() &&
         property->getSetterMethodDecl()) {
-      auto *getterMethod = property->getGetterMethodDecl();
-      auto *setterMethod = property->getSetterMethodDecl();
-      if (!impDecl->getInstanceMethod(setterMethod->getSelector()) &&
-          !impDecl->getInstanceMethod(getterMethod->getSelector())) {
+      auto *getterImpl = propertyImpl->getGetterMethodDecl();
+      auto *setterImpl = propertyImpl->getSetterMethodDecl();
+      if ((!getterImpl || getterImpl->isSynthesizedAccessorStub()) &&
+          (!setterImpl || setterImpl->isSynthesizedAccessorStub())) {
         SourceLocation loc = propertyImpl->getLocation();
         if (loc.isInvalid())
           loc = impDecl->getBeginLoc();
 
         Diag(loc, diag::warn_null_resettable_setter)
-          << setterMethod->getSelector() << property->getDeclName();
+          << setterImpl->getSelector() << property->getDeclName();
       }
     }
   }
 }
 
 void
 Sema::AtomicPropertySetterGetterRules (ObjCImplDecl* IMPDecl,
                                        ObjCInterfaceDecl* IDecl) {
for (ObjCContainerDecl::PropertyMap::iterator I = PM.begin(), E = PM.end();
     if (!(AttributesAsWritten & ObjCPropertyDecl::OBJC_PR_atomic) &&
         !(AttributesAsWritten & ObjCPropertyDecl::OBJC_PR_nonatomic)) {
       GetterMethod = Property->isClassProperty() ?
                      IMPDecl->getClassMethod(Property->getGetterName()) :
                      IMPDecl->getInstanceMethod(Property->getGetterName());
       SetterMethod = Property->isClassProperty() ?
                      IMPDecl->getClassMethod(Property->getSetterName()) :
                      IMPDecl->getInstanceMethod(Property->getSetterName());
+      if (GetterMethod && GetterMethod->isSynthesizedAccessorStub())
+        GetterMethod = nullptr;
+      if (SetterMethod && SetterMethod->isSynthesizedAccessorStub())
+        SetterMethod = nullptr;
       LookedUpGetterSetter = true;
       if (GetterMethod) {
         Diag(GetterMethod->getLocation(),
              diag::warn_default_atomic_custom_getter_setter)
           << Property->getIdentifier() << 0;
         Diag(Property->getLocation(), diag::note_property_declare);
       }
       if (SetterMethod) {
         Diag(SetterMethod->getLocation(),
              diag::warn_default_atomic_custom_getter_setter)
           << Property->getIdentifier() << 1;
         Diag(Property->getLocation(), diag::note_property_declare);
       }
     }
 
     // We only care about readwrite atomic property.
     if ((Attributes & ObjCPropertyDecl::OBJC_PR_nonatomic) ||
         !(Attributes & ObjCPropertyDecl::OBJC_PR_readwrite))
       continue;
     if (const ObjCPropertyImplDecl *PIDecl = IMPDecl->FindPropertyImplDecl(
             Property->getIdentifier(), Property->getQueryKind())) {
       if (PIDecl->getPropertyImplementation() == ObjCPropertyImplDecl::Dynamic)
         continue;
-      if (!LookedUpGetterSetter) {
-        GetterMethod = Property->isClassProperty() ?
-                       IMPDecl->getClassMethod(Property->getGetterName()) :
-                       IMPDecl->getInstanceMethod(Property->getGetterName());
-        SetterMethod = Property->isClassProperty() ?
-                       IMPDecl->getClassMethod(Property->getSetterName()) :
-                       IMPDecl->getInstanceMethod(Property->getSetterName());
-      }
-      if ((GetterMethod && !SetterMethod) || (!GetterMethod && SetterMethod)) {
+      GetterMethod = PIDecl->getGetterMethodDecl();
+      SetterMethod = PIDecl->getSetterMethodDecl();
+      if (GetterMethod && GetterMethod->isSynthesizedAccessorStub())
+        GetterMethod = nullptr;
+      if (SetterMethod && SetterMethod->isSynthesizedAccessorStub())
+        SetterMethod = nullptr;
+      if ((bool)GetterMethod ^ (bool)SetterMethod) {
         SourceLocation MethodLoc =
           (GetterMethod ? GetterMethod->getLocation()
                         : SetterMethod->getLocation());
         Diag(MethodLoc, diag::warn_atomic_property_rule)
           << Property->getIdentifier() << (GetterMethod != nullptr)
           << (SetterMethod != nullptr);
         // fixit stuff.
         if (Property->getLParenLoc().isValid() &&

 
 void Sema::DiagnoseOwningPropertyGetterSynthesis(const ObjCImplementationDecl *D) {
   if (getLangOpts().getGC() == LangOptions::GCOnly)
     return;
 
   for (const auto *PID : D->property_impls()) {
     const ObjCPropertyDecl *PD = PID->getPropertyDecl();
     if (PD && !PD->hasAttr<NSReturnsNotRetainedAttr>() &&
-        !PD->isClassProperty() &&
-        !D->getInstanceMethod(PD->getGetterName())) {
+        !PD->isClassProperty()) {
+      ObjCMethodDecl *IM = PID->getGetterMethodDecl();
+      if (IM && !IM->isSynthesizedAccessorStub())
+        continue;
       ObjCMethodDecl *method = PD->getGetterMethodDecl();
       if (!method)
         continue;
       ObjCMethodFamily family = method->getMethodFamily();
       if (family == OMF_alloc || family == OMF_copy ||
           family == OMF_mutableCopy || family == OMF_new) {
         if (getLangOpts().ObjCAutoRefCount)
           Diag(PD->getLocation(), diag::err_cocoa_naming_owned_rule);
if (property->getPropertyAttributes() &
       QualType modifiedTy = resultTy;
       if (auto nullability = AttributedType::stripOuterNullability(modifiedTy)) {
         if (*nullability == NullabilityKind::Unspecified)
           resultTy = Context.getAttributedType(attr::TypeNonNull,
                                                modifiedTy, modifiedTy);
       }
     }
 
-    GetterMethod = ObjCMethodDecl::Create(Context, Loc, Loc,
-                             property->getGetterName(),
-                             resultTy, nullptr, CD,
-                             !IsClassProperty, /*isVariadic=*/false,
-                             /*isPropertyAccessor=*/true,
-                             /*isImplicitlyDeclared=*/true, /*isDefined=*/false,
-                             (property->getPropertyImplementation() ==
-                              ObjCPropertyDecl::Optional) ?
-                             ObjCMethodDecl::Optional :
-                             ObjCMethodDecl::Required);
+    GetterMethod = ObjCMethodDecl::Create(
+        Context, Loc, Loc, property->getGetterName(), resultTy, nullptr, CD,
+        /*isPropertyAccessor=*/true, /*isSynthesizedAccessorStub=*/false,
+        (property->getPropertyImplementation() == ObjCPropertyDecl::Optional)
+            ? ObjCMethodDecl::Optional
+            : ObjCMethodDecl::Required);
     CD->addDecl(GetterMethod);
 
     AddPropertyAttrs(*this, GetterMethod, property);
 
     if (property->hasAttr<NSReturnsNotRetainedAttr>())
       GetterMethod->addAttr(NSReturnsNotRetainedAttr::CreateImplicit(Context,
                                                                      Loc));
 
if (!SetterMethod) {
       SourceLocation Loc = property->getLocation();
 
       SetterMethod =
         ObjCMethodDecl::Create(Context, Loc, Loc,
                                property->getSetterName(), Context.VoidTy,
                                nullptr, CD, !IsClassProperty,
                                /*isVariadic=*/false,
                                /*isPropertyAccessor=*/true,
+                               /*isSynthesizedAccessorStub=*/false,
                                /*isImplicitlyDeclared=*/true,
                                /*isDefined=*/false,
                                (property->getPropertyImplementation() ==
                                 ObjCPropertyDecl::Optional) ?
                                 ObjCMethodDecl::Optional :
                                 ObjCMethodDecl::Required);
 
       // Remove all qualifiers from the setter's parameter type.

clang/lib/Sema/SemaPseudoObject.cpp

else {
 
     AtIndexGetterSelector = S.Context.Selectors.getSelector(1, KeyIdents);
   }
 
   AtIndexGetter = S.LookupMethodInObjectType(AtIndexGetterSelector, ResultType,
                                              true /*instance*/);
 
   if (!AtIndexGetter && S.getLangOpts().DebuggerObjCLiteral) {
-    AtIndexGetter = ObjCMethodDecl::Create(S.Context, SourceLocation(),
-                           SourceLocation(), AtIndexGetterSelector,
-                           S.Context.getObjCIdType() /*ReturnType*/,
-                           nullptr /*TypeSourceInfo */,
-                           S.Context.getTranslationUnitDecl(),
-                           true /*Instance*/, false/*isVariadic*/,
-                           /*isPropertyAccessor=*/false,
-                           /*isImplicitlyDeclared=*/true, /*isDefined=*/false,
-                           ObjCMethodDecl::Required,
-                           false);
+    AtIndexGetter = ObjCMethodDecl::Create(
+        S.Context, SourceLocation(), SourceLocation(), AtIndexGetterSelector,
+        S.Context.getObjCIdType() /*ReturnType*/, nullptr /*TypeSourceInfo */,
+        S.Context.getTranslationUnitDecl(), true /*Instance*/,
+        false /*isVariadic*/,
+        /*isSynthesizedAccessorStub=*/false,
+        ObjCMethodDecl::Required, false);
     ParmVarDecl *Argument = ParmVarDecl::Create(S.Context, AtIndexGetter,
                                                 SourceLocation(), SourceLocation(),
                                                 arrayRef ? &S.Context.Idents.get("index")
                                                          : &S.Context.Idents.get("key"),
                                                 arrayRef ? S.Context.UnsignedLongTy
                                                          : S.Context.getObjCIdType(),
                                                 /*TInfo=*/nullptr,
                                                 SC_None,
bool ObjCSubscriptOpBuilder::findAtIndexSetter() {
   if (!AtIndexSetter && S.getLangOpts().DebuggerObjCLiteral) {
     TypeSourceInfo *ReturnTInfo = nullptr;
     QualType ReturnType = S.Context.VoidTy;
     AtIndexSetter = ObjCMethodDecl::Create(
         S.Context, SourceLocation(), SourceLocation(), AtIndexSetterSelector,
         ReturnType, ReturnTInfo, S.Context.getTranslationUnitDecl(),
         true /*Instance*/, false /*isVariadic*/,
         /*isPropertyAccessor=*/false,
+        /*isSynthesizedAccessorStub=*/false,
         /*isImplicitlyDeclared=*/true, /*isDefined=*/false,
         ObjCMethodDecl::Required, false);
     SmallVector<ParmVarDecl *, 2> Params;
     ParmVarDecl *object = ParmVarDecl::Create(S.Context, AtIndexSetter,
                                                 SourceLocation(), SourceLocation(),
                                                 &S.Context.Idents.get("object"),
                                                 S.Context.getObjCIdType(),
                                                 /*TInfo=*/nullptr,

clang/lib/Serialization/ASTReaderDecl.cpp

if (Record.readInt()) {
     Reader.PendingBodies[MD] = GetCurrentCursorOffset();
     HasPendingBody = true;
     MD->setSelfDecl(ReadDeclAs<ImplicitParamDecl>());
     MD->setCmdDecl(ReadDeclAs<ImplicitParamDecl>());
   }
   MD->setInstanceMethod(Record.readInt());
   MD->setVariadic(Record.readInt());
   MD->setPropertyAccessor(Record.readInt());
+  MD->setSynthesizedAccessorStub(Record.readInt());
   MD->setDefined(Record.readInt());
   MD->setOverriding(Record.readInt());
   MD->setHasSkippedBody(Record.readInt());
 
   MD->setIsRedeclaration(Record.readInt());
   MD->setHasRedeclaration(Record.readInt());
   if (MD->hasRedeclaration())
     Reader.getContext().setObjCMethodRedeclaration(MD,

 }
 
 void ASTDeclReader::VisitObjCPropertyImplDecl(ObjCPropertyImplDecl *D) {
   VisitDecl(D);
   D->setAtLoc(ReadSourceLocation());
   D->setPropertyDecl(ReadDeclAs<ObjCPropertyDecl>());
   D->PropertyIvarDecl = ReadDeclAs<ObjCIvarDecl>();
   D->IvarLoc = ReadSourceLocation();
+  D->setGetterMethodDecl(ReadDeclAs<ObjCMethodDecl>());
+  D->setSetterMethodDecl(ReadDeclAs<ObjCMethodDecl>());
   D->setGetterCXXConstructor(Record.readExpr());
   D->setSetterCXXAssignment(Record.readExpr());
 }
 
 void ASTDeclReader::VisitFieldDecl(FieldDecl *FD) {
   VisitDeclaratorDecl(FD);
   FD->Mutable = Record.readInt();
 

clang/lib/Serialization/ASTWriterDecl.cpp

void ASTDeclWriter::VisitObjCMethodDecl(ObjCMethodDecl *D) {
   if (HasBodyStuff) {
     Record.AddStmt(D->getBody());
     Record.AddDeclRef(D->getSelfDecl());
     Record.AddDeclRef(D->getCmdDecl());
   }
   Record.push_back(D->isInstanceMethod());
   Record.push_back(D->isVariadic());
   Record.push_back(D->isPropertyAccessor());
+  Record.push_back(D->isSynthesizedAccessorStub());
   Record.push_back(D->isDefined());
   Record.push_back(D->isOverriding());
   Record.push_back(D->hasSkippedBody());
 
   Record.push_back(D->isRedeclaration());
   Record.push_back(D->hasRedeclaration());
   if (D->hasRedeclaration()) {
     assert(Context.getObjCMethodRedeclaration(D));

 }
 
 void ASTDeclWriter::VisitObjCPropertyImplDecl(ObjCPropertyImplDecl *D) {
   VisitDecl(D);
   Record.AddSourceLocation(D->getBeginLoc());
   Record.AddDeclRef(D->getPropertyDecl());
   Record.AddDeclRef(D->getPropertyIvarDecl());
   Record.AddSourceLocation(D->getPropertyIvarDeclLoc());
+  Record.AddDeclRef(D->getGetterMethodDecl());
+  Record.AddDeclRef(D->getSetterMethodDecl());
   Record.AddStmt(D->getGetterCXXConstructor());
   Record.AddStmt(D->getSetterCXXAssignment());
   Code = serialization::DECL_OBJC_PROPERTY_IMPL;
 }
 
 void ASTDeclWriter::VisitFieldDecl(FieldDecl *D) {
   VisitDeclaratorDecl(D);
   Record.push_back(D->isMutable());

clang/lib/StaticAnalyzer/Checkers/DirectIvarAssignment.cpp

void DirectIvarAssignment::checkASTDecl(const ObjCImplementationDecl *D,
 
   for (const auto *M : D->instance_methods()) {
     AnalysisDeclContext *DCtx = Mgr.getAnalysisDeclContext(M);
 
     if ((*ShouldSkipMethod)(M))
       continue;
 
     const Stmt *Body = M->getBody();
+    if (M->isSynthesizedAccessorStub())
+      continue;
     assert(Body);
 
     MethodCrawler MC(IvarToPropMap, M->getCanonicalDecl(), InterD, BR, this,
                      DCtx);
     MC.VisitStmt(Body);
   }
 }
 

clang/lib/StaticAnalyzer/Core/CallEvent.cpp

ObjCMessageKind ObjCMethodCall::getMessageKind() const {
   ObjCMessageDataTy Info = ObjCMessageDataTy::getFromOpaqueValue(Data);
   if (!Info.getPointer())
     return OCM_Message;
   return static_cast<ObjCMessageKind>(Info.getInt());
 }
 
 const ObjCPropertyDecl *ObjCMethodCall::getAccessedProperty() const {
   // Look for properties accessed with property syntax (foo.bar = ...)
-  if ( getMessageKind() == OCM_PropertyAccess) {
+  if (getMessageKind() == OCM_PropertyAccess) {
     const PseudoObjectExpr *POE = getContainingPseudoObjectExpr();
     assert(POE && "Property access without PseudoObjectExpr?");
 
     const Expr *Syntactic = getSyntacticFromForPseudoObjectExpr(POE);
     auto *RefExpr = cast<ObjCPropertyRefExpr>(Syntactic);
 
     if (RefExpr->isExplicitProperty())
       return RefExpr->getExplicitProperty();

clang/test/AST/ast-dump-decl-json.m

 // CHECK-NEXT:    "ivarDecl": {
 // CHECK-NEXT:     "id": "0x{{.*}}",
 // CHECK-NEXT:     "kind": "ObjCIvarDecl",
 // CHECK-NEXT:     "name": "bar",
 // CHECK-NEXT:     "type": {
 // CHECK-NEXT:      "qualType": "int"
 // CHECK-NEXT:     }
 // CHECK-NEXT:    }
-// CHECK-NEXT:   }
+// CHECK-NEXT:   },
+// CHECK-NEXT:   {
+// CHECK-NEXT:     "id": "0x{{.*}}", 
+// CHECK-NEXT:     "kind": "ObjCMethodDecl",
+// CHECK-NEXT:     "loc": {
+// CHECK-NEXT:       "offset": 1109,
+// CHECK-NEXT:       "line": 70,
+// CHECK-NEXT:       "col": 1,
+// CHECK-NEXT:       "tokLen": 1
+// CHECK-NEXT:     },
+// CHECK-NEXT:     "range": {
+// CHECK-NEXT:       "begin": {
+// CHECK-NEXT:         "offset": 1109,
+// CHECK-NEXT:         "col": 1,
+// CHECK-NEXT:         "tokLen": 1
+// CHECK-NEXT:       },
+// CHECK-NEXT:       "end": {
+// CHECK-NEXT:         "offset": 1121,
+// CHECK-NEXT:         "col": 13,
+// CHECK-NEXT:         "tokLen": 3
+// CHECK-NEXT:       }
+// CHECK-NEXT:     },
+// CHECK-NEXT:     "isImplicit": true,
+// CHECK-NEXT:     "name": "getterFoo",
+// CHECK-NEXT:     "returnType": {
+// CHECK-NEXT:       "qualType": "int"
+// CHECK-NEXT:     },
+// CHECK-NEXT:     "instance": true
+// CHECK-NEXT:   },
+// CHECK-NEXT:   {
+// CHECK-NEXT:     "id": "0x{{.*}}",
+// CHECK-NEXT:     "kind": "ObjCMethodDecl",
+// CHECK-NEXT:     "loc": {
+// CHECK-NEXT:       "offset": 1109,
+// CHECK-NEXT:       "col": 1,
+// CHECK-NEXT:       "tokLen": 1
+// CHECK-NEXT:     },
+// CHECK-NEXT:     "range": {
+// CHECK-NEXT:       "begin": {
+// CHECK-NEXT:         "offset": 1109,
+// CHECK-NEXT:         "col": 1,
+// CHECK-NEXT:         "tokLen": 1
+// CHECK-NEXT:       },
+// CHECK-NEXT:       "end": {
+// CHECK-NEXT:         "offset": 1121,
+// CHECK-NEXT:         "col": 13,
+// CHECK-NEXT:         "tokLen": 3
+// CHECK-NEXT:       }
+// CHECK-NEXT:     },
+// CHECK-NEXT:     "isImplicit": true,
+// CHECK-NEXT:     "name": "setterFoo:",
+// CHECK-NEXT:     "returnType": {
+// CHECK-NEXT:       "qualType": "void"
+// CHECK-NEXT:     },
+// CHECK-NEXT:     "instance": true,
+// CHECK-NEXT:     "inner": [
+// CHECK-NEXT:       {
+// CHECK-NEXT:         "id": "0x{{.*}}",
+// CHECK-NEXT:         "kind": "ParmVarDecl",
+// CHECK-NEXT:         "loc": {
+// CHECK-NEXT:           "offset": 1033,
+// CHECK-NEXT:           "line": 63,
+// CHECK-NEXT:           "col": 52,
+// CHECK-NEXT:           "tokLen": 3
+// CHECK-NEXT:         },
+// CHECK-NEXT:         "range": {
+// CHECK-NEXT:           "begin": {
+// CHECK-NEXT:             "offset": 1033,
+// CHECK-NEXT:             "col": 52,
+// CHECK-NEXT:             "tokLen": 3
+// CHECK-NEXT:           },
+// CHECK-NEXT:           "end": {
+// CHECK-NEXT:             "offset": 1033,
+// CHECK-NEXT:             "col": 52,
+// CHECK-NEXT:             "tokLen": 3
+// CHECK-NEXT:           }
+// CHECK-NEXT:         },
+// CHECK-NEXT:         "name": "foo",
+// CHECK-NEXT:         "type": {
+// CHECK-NEXT:           "qualType": "int"
+// CHECK-NEXT:         }
+// CHECK-NEXT:       }
+// CHECK-NEXT:      ]
+// CHECK-NEXT:    },
+// CHECK-NEXT:    {
+// CHECK-NEXT:      "id": "0x{{.*}}",
+// CHECK-NEXT:      "kind": "ObjCMethodDecl",
+// CHECK-NEXT:      "loc": {
+// CHECK-NEXT:        "offset": 1128,
+// CHECK-NEXT:        "line": 71,
+// CHECK-NEXT:        "col": 1,
+// CHECK-NEXT:        "tokLen": 1
+// CHECK-NEXT:      },
+// CHECK-NEXT:      "range": {
+// CHECK-NEXT:        "begin": {
+// CHECK-NEXT:          "offset": 1128,
+// CHECK-NEXT:          "col": 1,
+// CHECK-NEXT:          "tokLen": 1
+// CHECK-NEXT:        },
+// CHECK-NEXT:        "end": {
+// CHECK-NEXT:          "offset": 1140,
+// CHECK-NEXT:          "col": 13,
+// CHECK-NEXT:          "tokLen": 3
+// CHECK-NEXT:        }
+// CHECK-NEXT:      },
+// CHECK-NEXT:      "isImplicit": true,
+// CHECK-NEXT:      "name": "bar",
+// CHECK-NEXT:      "returnType": {
+// CHECK-NEXT:        "qualType": "int"
+// CHECK-NEXT:      },
+// CHECK-NEXT:      "instance": true
+// CHECK-NEXT:    },
+// CHECK-NEXT:    {
+// CHECK-NEXT:      "id": "0x{{.*}}",
+// CHECK-NEXT:      "kind": "ObjCMethodDecl",
+// CHECK-NEXT:      "loc": {
+// CHECK-NEXT:        "offset": 1128,
+// CHECK-NEXT:        "col": 1,
+// CHECK-NEXT:        "tokLen": 1
+// CHECK-NEXT:      },
+// CHECK-NEXT:      "range": {
+// CHECK-NEXT:        "begin": {
+// CHECK-NEXT:          "offset": 1128,
+// CHECK-NEXT:          "col": 1,
+// CHECK-NEXT:          "tokLen": 1
+// CHECK-NEXT:        },
+// CHECK-NEXT:        "end": {
+// CHECK-NEXT:          "offset": 1140,
+// CHECK-NEXT:          "col": 13,
+// CHECK-NEXT:          "tokLen": 3
+// CHECK-NEXT:        }
+// CHECK-NEXT:      },
+// CHECK-NEXT:      "isImplicit": true,
+// CHECK-NEXT:      "name": "setBar:",
+// CHECK-NEXT:      "returnType": {
+// CHECK-NEXT:        "qualType": "void"
+// CHECK-NEXT:      },
+// CHECK-NEXT:      "instance": true,
+// CHECK-NEXT:      "inner": [
+// CHECK-NEXT:        {
+// CHECK-NEXT:          "id": "0x{{.*}}",
+// CHECK-NEXT:          "kind": "ParmVarDecl",
+// CHECK-NEXT:          "loc": {
+// CHECK-NEXT:            "offset": 1052,
+// CHECK-NEXT:            "line": 64,
+// CHECK-NEXT:            "col": 15,
+// CHECK-NEXT:            "tokLen": 3
+// CHECK-NEXT:          },
+// CHECK-NEXT:          "range": {
+// CHECK-NEXT:            "begin": {
+// CHECK-NEXT:              "offset": 1052,
+// CHECK-NEXT:              "col": 15,
+// CHECK-NEXT:              "tokLen": 3
+// CHECK-NEXT:            },
+// CHECK-NEXT:            "end": {
+// CHECK-NEXT:              "offset": 1052,
+// CHECK-NEXT:              "col": 15,
+// CHECK-NEXT:              "tokLen": 3
+// CHECK-NEXT:            }
+// CHECK-NEXT:          },
+// CHECK-NEXT:          "name": "bar",
+// CHECK-NEXT:          "type": {
+// CHECK-NEXT:            "qualType": "int"
+// CHECK-NEXT:          }
+// CHECK-NEXT:        }
+// CHECK-NEXT:      ]
+// CHECK-NEXT:    }
 // CHECK-NEXT:  ]
 // CHECK-NEXT: }
 
 
 // CHECK:  "kind": "FunctionDecl",
 // CHECK-NEXT:  "loc": {
 // CHECK-NEXT:   "offset": 1156,
 // CHECK-NEXT:   "file": "{{.*}}",

clang/test/Analysis/Inputs/expected-plists/nullability-notes.m.plist

<array>
    <key>line</key><integer>17</integer>
    <key>col</key><integer>3</integer>
    <key>file</key><integer>0</integer>
   </dict>
   <key>ExecutedLines</key>
   <dict>
    <key>0</key>
    <array>
-    <integer>10</integer>
     <integer>14</integer>
     <integer>16</integer>
     <integer>17</integer>
    </array>
   </dict>
   </dict>
  </array>
  <key>files</key>
  <array>
  </array>
 </dict>
 </plist>

clang/test/CodeGenObjC/debug-info-synthesis.m

 
 int main(int argc, char *argv[]) {
   @autoreleasepool {
     Foo *f = [Foo new];
     [f bork];
   }
 }
 
-// CHECK: ![[FILE:.*]] = !DIFile(filename: "{{[^"]+}}foo.h"
+// CHECK: ![[FILE:.*]] = !DIFile(filename: "foo.m"
 // CHECK: !DISubprogram(name: "-[Foo setDict:]"
 // CHECK-SAME:          file: ![[FILE]],
-// CHECK-SAME:          line: 8,
+// CHECK-SAME:          line: 7,
 // CHECK-SAME:          DISPFlagLocalToUnit | DISPFlagDefinition

clang/test/CodeGenObjC/debug-property-synth.m

 // RUN: %clang_cc1 -triple %itanium_abi_triple -emit-llvm -debug-info-kind=limited %s -o - | FileCheck %s
 // rdar://problem/9468526
 //
 // Setting a breakpoint on a property should create breakpoints in
 // synthesized getters/setters.
 //
 @interface I {
   int _p1;
 }
+@property int p1;
+@end
+
+@implementation I
 // Test that the linetable entries for the synthesized getter and
 // setter are correct.
 //
 // CHECK: define {{.*}}[I p1]
 // CHECK-NOT: ret
 // CHECK: load {{.*}}, !dbg ![[DBG1:[0-9]+]]
 //
 // CHECK: define {{.*}}[I setP1:]
 // CHECK-NOT: ret
 // CHECK: load {{.*}}, !dbg ![[DBG2:[0-9]+]]
 //
 // CHECK: !DISubprogram(name: "-[I p1]",{{.*}} line: [[@LINE+4]],{{.*}} DISPFlagLocalToUnit | DISPFlagDefinition
 // CHECK: ![[DBG1]] = !DILocation(line: [[@LINE+3]],
 // CHECK: !DISubprogram(name: "-[I setP1:]",{{.*}} line: [[@LINE+2]],{{.*}} DISPFlagLocalToUnit | DISPFlagDefinition
 // CHECK: ![[DBG2]] = !DILocation(line: [[@LINE+1]],
-@property int p1;
-@end
-
-@implementation I
 @synthesize p1 = _p1;
 @end
 
 int main() {
   I *myi;
   myi.p1 = 2;
   return myi.p1;
 }

clang/test/CodeGenObjC/debuginfo-properties.m

 // RUN: %clang_cc1 -debug-info-kind=limited -emit-llvm -triple x86_64-apple-darwin -o - %s | FileCheck %s
 // Check that we emit the correct method names for properties from a protocol.
 // rdar://problem/13798000
 @protocol NSObject
 - (id)init;
 @end
 @interface NSObject <NSObject> {}
 @end
 
 @class Selection;
 
 @protocol HasASelection <NSObject>
 @property (nonatomic, retain) Selection* selection;
-// CHECK: !DISubprogram(name: "-[MyClass selection]"
-// CHECK-SAME:          line: [[@LINE-2]]
-// CHECK-SAME:          DISPFlagLocalToUnit | DISPFlagDefinition
-// CHECK: !DISubprogram(name: "-[MyClass setSelection:]"
-// CHECK-SAME:          line: [[@LINE-5]]
-// CHECK-SAME:          DISPFlagLocalToUnit | DISPFlagDefinition
-// CHECK: !DISubprogram(name: "-[OtherClass selection]"
-// CHECK-SAME:          line: [[@LINE-8]]
-// CHECK-SAME:          DISPFlagLocalToUnit | DISPFlagDefinition
-// CHECK: !DISubprogram(name: "-[OtherClass setSelection:]"
-// CHECK-SAME:          line: [[@LINE-11]]
-// CHECK-SAME:          DISPFlagLocalToUnit | DISPFlagDefinition
-
 @end
 
 @interface MyClass : NSObject <HasASelection> {
   Selection *_selection;
 }
 @end
 
 @implementation MyClass
 @synthesize selection = _selection;
+// CHECK: !DISubprogram(name: "-[MyClass selection]"
+// CHECK-SAME:          line: [[@LINE-2]]
+// CHECK-SAME:          DISPFlagLocalToUnit | DISPFlagDefinition
+// CHECK: !DISubprogram(name: "-[MyClass setSelection:]"
+// CHECK-SAME:          line: [[@LINE-5]]
+// CHECK-SAME:          DISPFlagLocalToUnit | DISPFlagDefinition
 @end
 
 @interface OtherClass : NSObject <HasASelection> {
   Selection *_selection;
 }
 @end
 @implementation OtherClass
 @synthesize selection = _selection;
+// CHECK: !DISubprogram(name: "-[OtherClass selection]"
+// CHECK-SAME:          line: [[@LINE-2]]
+// CHECK-SAME:          DISPFlagLocalToUnit | DISPFlagDefinition
+// CHECK: !DISubprogram(name: "-[OtherClass setSelection:]"
+// CHECK-SAME:          line: [[@LINE-5]]
+// CHECK-SAME:          DISPFlagLocalToUnit | DISPFlagDefinition
 @end

clang/test/CodeGenObjC/instance-method-metadata.m

 // REQUIRES: x86-registered-target
-// RUN: %clang_cc1 -triple x86_64-apple-darwin10 -S -o %t %s 
-// RUN: FileCheck < %t %s
+// RUN: %clang_cc1 -triple x86_64-apple-darwin10 -S %s -o - | FileCheck %s
 
 // rdar://9072317
 
 /** The problem looks like clang getting confused when a single translation unit 
     contains a protocol with a property and two classes that implement that protocol 
     and synthesize the property.
 */
 

clang/test/SemaObjC/iboutlet.m

 // RUN: %clang_cc1 -fsyntax-only -fobjc-arc -Wno-objc-root-class -Warc-repeated-use-of-weak -fobjc-runtime-has-weak -verify %s
 // RUN: %clang_cc1 -x objective-c++ -fsyntax-only -fobjc-arc -Wno-objc-root-class -Warc-repeated-use-of-weak -fobjc-runtime-has-weak -verify %s
 // rdar://11448209
 
 #define READONLY readonly
 
 @class NSView;
 
 IB_DESIGNABLE @interface I
 @property (getter = MyGetter, readonly, assign) IBOutlet NSView *myView; // expected-warning {{readonly IBOutlet property 'myView' when auto-synthesized may not work correctly with 'nib' loader}} expected-note {{property should be changed to be readwrite}}
 
 IBInspectable @property (readonly) IBOutlet NSView *myView1; // expected-warning {{readonly IBOutlet property 'myView1' when auto-synthesized may not work correctly with 'nib' loader}} expected-note {{property should be changed to be readwrite}}
 
-@property (getter = MyGetter, READONLY) IBOutlet NSView *myView2; // expected-warning {{readonly IBOutlet property 'myView2' when auto-synthesized may not work correctly with 'nib' loader}}
+@property (getter = MyGetter2, READONLY) IBOutlet NSView *myView2; // expected-warning {{readonly IBOutlet property 'myView2' when auto-synthesized may not work correctly with 'nib' loader}}
 
 @end
 
 @implementation I
 @end
 
 
 // rdar://13123861

clang/tools/libclang/CIndex.cpp

bool CursorVisitor::VisitDeclContext(DeclContext *DC) {
   // iteration over all Decls contained lexically within an ObjC container.
   SaveAndRestore<DeclContext::decl_iterator*> DI_saved(DI_current, &I);
   SaveAndRestore<DeclContext::decl_iterator> DE_saved(DE_current, E);
 
   for ( ; I != E; ++I) {
     Decl *D = *I;
     if (D->getLexicalDeclContext() != DC)
       continue;
+    // Filter out synthesized property accessor redeclarations.
+    if (isa<ObjCImplDecl>(DC))
+      if (auto *OMD = dyn_cast<ObjCMethodDecl>(D))
+        if (OMD->isSynthesizedAccessorStub())
+          continue;
     const Optional<bool> V = handleDeclForVisitation(D);
     if (!V.hasValue())
       continue;
     return V.getValue();
   }
   return false;
 }