diff --git a/lib/Sema/SemaDeclObjC.cpp b/lib/Sema/SemaDeclObjC.cpp
index 115a433..f627c23 100644
--- a/lib/Sema/SemaDeclObjC.cpp
+++ b/lib/Sema/SemaDeclObjC.cpp
@@ -2019,6 +2019,32 @@
               Diag(AtLoc, diag::warn_property_attr_mismatch);
               Diag(PIDecl->getLocation(), diag::note_property_declare);
             }
+            DeclContext *DC = dyn_cast<DeclContext>(CCPrimary);
+            assert(DC && "ClassDecl is not a DeclContext");
+            DeclContext::lookup_result Found = 
+              DC->lookup(PIDecl->getDeclName());
+            bool PropertyInPrimaryClass = false;
+            for (; Found.first != Found.second; ++Found.first)
+              if (isa<ObjCPropertyDecl>(*Found.first)) {
+                PropertyInPrimaryClass = true;
+                break;
+              }
+            if (!PropertyInPrimaryClass) {
+              // Protocol is not in the primary class. Must build one for it.
+              ObjCDeclSpec ProtocolPropertyODS;
+              // FIXME. Assuming that ObjCDeclSpec::ObjCPropertyAttributeKind and
+              // ObjCPropertyDecl::PropertyAttributeKind have identical values.
+              // Should consolidate both into one enum type.
+              ProtocolPropertyODS.setPropertyAttributes(
+                (ObjCDeclSpec::ObjCPropertyAttributeKind)PIkind);
+              DeclPtrTy ProtocolPtrTy = 
+                ActOnProperty(S, AtLoc, FD, ProtocolPropertyODS, 
+                              PIDecl->getGetterName(), 
+                              PIDecl->getSetterName(), 
+                              DeclPtrTy::make(CCPrimary), isOverridingProperty, 
+                              MethodImplKind);
+              PIDecl = ProtocolPtrTy.getAs<ObjCPropertyDecl>();
+            }
             PIDecl->makeitReadWriteAttribute();
             if (Attributes & ObjCDeclSpec::DQ_PR_retain)
               PIDecl->setPropertyAttributes(ObjCPropertyDecl::OBJC_PR_retain);
diff --git a/test/SemaObjC/continuation-class-property.m b/test/SemaObjC/continuation-class-property.m
new file mode 100644
index 0000000..c48a23d
--- /dev/null
+++ b/test/SemaObjC/continuation-class-property.m
@@ -0,0 +1,24 @@
+// RUN: %clang_cc1  -fsyntax-only -verify %s
+// radar 7509234
+
+@protocol Foo
+@property (readonly, copy) id foos;
+@end
+
+@interface Bar <Foo> {
+}
+
+@end
+
+@interface Baz  <Foo> {
+}
+@end
+
+@interface Bar ()
+@property (readwrite, copy) id foos;
+@end
+
+@interface Baz ()
+@property (readwrite, copy) id foos;
+@end
+