5 files changed, 30 insertions, 6 deletions
diff --git a/lib/AST/DeclObjC.cpp b/lib/AST/DeclObjC.cpp
index 4167841838..28c7a49a13 100644
--- a/lib/AST/DeclObjC.cpp
+++ b/lib/AST/DeclObjC.cpp
@@ -604,10 +604,17 @@ ObjCIvarDecl *ObjCIvarDecl::Create(ASTContext &C, ObjCContainerDecl *DC,
     // decl contexts, the previously built IvarList must be rebuilt.
     ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(DC);
     if (!ID) {
-      if (ObjCImplementationDecl *IM = dyn_cast<ObjCImplementationDecl>(DC))
+      if (ObjCImplementationDecl *IM = dyn_cast<ObjCImplementationDecl>(DC)) {
         ID = IM->getClassInterface();
-      else
-        ID = (cast<ObjCCategoryDecl>(DC))->getClassInterface();
+        if (BW)
+          IM->setHasSynthBitfield(true);
+      }
+      else {
+        ObjCCategoryDecl *CD = cast<ObjCCategoryDecl>(DC);
+        ID = CD->getClassInterface();
+        if (BW)
+          CD->setHasSynthBitfield(true);
+      }
     }
     ID->setIvarList(0);
   }
diff --git a/lib/CodeGen/CodeGenModule.cpp b/lib/CodeGen/CodeGenModule.cpp
index f26fa3c610..e6388373ea 100644
--- a/lib/CodeGen/CodeGenModule.cpp
+++ b/lib/CodeGen/CodeGenModule.cpp
@@ -1940,9 +1940,16 @@ void CodeGenModule::EmitTopLevelDecl(Decl *D) {
   // Forward declarations, no (immediate) code generation.
   case Decl::ObjCClass:
   case Decl::ObjCForwardProtocol:
-  case Decl::ObjCCategory:
   case Decl::ObjCInterface:
     break;
+  
+    case Decl::ObjCCategory: {
+      ObjCCategoryDecl *CD = cast<ObjCCategoryDecl>(D);
+      if (CD->IsClassExtension() && CD->hasSynthBitfield())
+        Context.ResetObjCLayout(CD->getClassInterface());
+      break;
+    }
+      
 
   case Decl::ObjCProtocol:
     Runtime->GenerateProtocol(cast<ObjCProtocolDecl>(D));
@@ -1956,6 +1963,8 @@ void CodeGenModule::EmitTopLevelDecl(Decl *D) {
 
   case Decl::ObjCImplementation: {
     ObjCImplementationDecl *OMD = cast<ObjCImplementationDecl>(D);
+    if (Features.ObjCNonFragileABI2 && OMD->hasSynthBitfield())
+      Context.ResetObjCLayout(OMD->getClassInterface());
     EmitObjCPropertyImplementations(OMD);
     EmitObjCIvarInitializations(OMD);
     Runtime->GenerateClass(OMD);
diff --git a/lib/Sema/SemaDecl.cpp b/lib/Sema/SemaDecl.cpp
index 0f9d12e6fe..f08092f922 100644
--- a/lib/Sema/SemaDecl.cpp
+++ b/lib/Sema/SemaDecl.cpp
@@ -6349,9 +6349,13 @@ Decl *Sema::ActOnIvar(Scope *S,
   ObjCContainerDecl *EnclosingContext;
   if (ObjCImplementationDecl *IMPDecl =
       dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) {
+    if (!LangOpts.ObjCNonFragileABI2) {
     // Case of ivar declared in an implementation. Context is that of its class.
-    EnclosingContext = IMPDecl->getClassInterface();
-    assert(EnclosingContext && "Implementation has no class interface!");
+      EnclosingContext = IMPDecl->getClassInterface();
+      assert(EnclosingContext && "Implementation has no class interface!");
+    }
+    else
+      EnclosingContext = EnclosingDecl;
   } else {
     if (ObjCCategoryDecl *CDecl = 
         dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) {
diff --git a/lib/Serialization/ASTReaderDecl.cpp b/lib/Serialization/ASTReaderDecl.cpp
index e8bf195787..0ee8c83183 100644
--- a/lib/Serialization/ASTReaderDecl.cpp
+++ b/lib/Serialization/ASTReaderDecl.cpp
@@ -476,6 +476,7 @@ void ASTDeclReader::VisitObjCCategoryDecl(ObjCCategoryDecl *CD) {
   CD->setProtocolList(ProtoRefs.data(), NumProtoRefs, ProtoLocs.data(),
                       *Reader.getContext());
   CD->setNextClassCategory(cast_or_null<ObjCCategoryDecl>(Reader.GetDecl(Record[Idx++])));
+  CD->setHasSynthBitfield(Record[Idx++]);
   CD->setAtLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
   CD->setCategoryNameLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
 }
@@ -524,6 +525,7 @@ void ASTDeclReader::VisitObjCImplementationDecl(ObjCImplementationDecl *D) {
               cast_or_null<ObjCInterfaceDecl>(Reader.GetDecl(Record[Idx++])));
   llvm::tie(D->IvarInitializers, D->NumIvarInitializers)
       = Reader.ReadCXXBaseOrMemberInitializers(Cursor, Record, Idx);
+  D->setHasSynthBitfield(Record[Idx++]);
 }
 
 
diff --git a/lib/Serialization/ASTWriterDecl.cpp b/lib/Serialization/ASTWriterDecl.cpp
index a5d2ce21c2..3edb6302f8 100644
--- a/lib/Serialization/ASTWriterDecl.cpp
+++ b/lib/Serialization/ASTWriterDecl.cpp
@@ -428,6 +428,7 @@ void ASTDeclWriter::VisitObjCCategoryDecl(ObjCCategoryDecl *D) {
        PL != PLEnd; ++PL)
     Writer.AddSourceLocation(*PL, Record);
   Writer.AddDeclRef(D->getNextClassCategory(), Record);
+  Record.push_back(D->hasSynthBitfield());
   Writer.AddSourceLocation(D->getAtLoc(), Record);
   Writer.AddSourceLocation(D->getCategoryNameLoc(), Record);
   Code = serialization::DECL_OBJC_CATEGORY;
@@ -473,6 +474,7 @@ void ASTDeclWriter::VisitObjCImplementationDecl(ObjCImplementationDecl *D) {
   Writer.AddDeclRef(D->getSuperClass(), Record);
   Writer.AddCXXBaseOrMemberInitializers(D->IvarInitializers,
                                         D->NumIvarInitializers, Record);
+  Record.push_back(D->hasSynthBitfield());
   Code = serialization::DECL_OBJC_IMPLEMENTATION;
 }