diff --git a/clang/lib/Sema/SemaExprObjC.cpp b/clang/lib/Sema/SemaExprObjC.cpp
index 2f3949fe604e..c9cfc92f4d6b 100644
--- a/clang/lib/Sema/SemaExprObjC.cpp
+++ b/clang/lib/Sema/SemaExprObjC.cpp
@@ -170,6 +170,12 @@ Sema::ExprResult Sema::ActOnClassMessage(
   ObjCMethodDecl *Method = ClassDecl->lookupClassMethod(Sel);
   QualType returnType;
   
+  // If we have an implementation in scope, check "private" methods.
+  if (!Method) {
+    if (ObjCImplementationDecl *ImpDecl = 
+        ObjCImplementations[ClassDecl->getIdentifier()])
+      Method = ImpDecl->getClassMethod(Sel);
+  }
   // Before we give up, check if the selector is an instance method.
   if (!Method)
     Method = ClassDecl->lookupInstanceMethod(Sel);
diff --git a/clang/test/Sema/method-lookup.m b/clang/test/Sema/method-lookup.m
new file mode 100644
index 000000000000..4dfbc7466275
--- /dev/null
+++ b/clang/test/Sema/method-lookup.m
@@ -0,0 +1,34 @@
+// RUN: clang -fsyntax-only -verify %s
+typedef signed char BOOL;
+typedef int NSInteger;
+
+@protocol NSObject
+- (BOOL)isEqual:(id)object;
+- (BOOL)respondsToSelector:(SEL)s;
+@end
+
+@interface NSObject <NSObject> {}
+@end
+
+@class NSString, NSData, NSMutableData, NSMutableDictionary, NSMutableArray;
+
+@protocol PBXCompletionItem
+- (NSString *) name;
+- (NSInteger)priority;
+- setPriority:(NSInteger)p;
+@end
+
+@implementation PBXCodeAssistant // expected-warning{{cannot find interface declaration for 'PBXCodeAssistant'}}
+static NSMutableArray * recentCompletions = ((void *)0);
++ (float) factorForRecentCompletion:(NSString *) completion
+{
+    for (NSObject<PBXCompletionItem> * item in [self completionItems]) // expected-warning{{method '-completionItems' not found (return type defaults to 'id')}}
+    {
+        if ([item respondsToSelector:@selector(setPriority:)])
+        {
+            [(id)item setPriority:[item priority] / [PBXCodeAssistant factorForRecentCompletion:[item name]]];
+        }
+    }
+}
+@end
+