diff --git a/lib/Checker/ObjCUnusedIVarsChecker.cpp b/lib/Checker/ObjCUnusedIVarsChecker.cpp
index 2523cff..edeba74 100644
--- a/lib/Checker/ObjCUnusedIVarsChecker.cpp
+++ b/lib/Checker/ObjCUnusedIVarsChecker.cpp
@@ -113,9 +113,11 @@
     // (a) aren't private
     // (b) explicitly marked unused
     // (c) are iboutlets
+    // (d) are unnamed bitfields
     if (ID->getAccessControl() != ObjCIvarDecl::Private ||
         ID->getAttr<UnusedAttr>() || ID->getAttr<IBOutletAttr>() ||
-        ID->getAttr<IBOutletCollectionAttr>())
+        ID->getAttr<IBOutletCollectionAttr>() ||
+        ID->isUnnamedBitfield())
       continue;
 
     M[ID] = Unused;
diff --git a/test/Analysis/unused-ivars.m b/test/Analysis/unused-ivars.m
index 14c43a8..c88d148 100644
--- a/test/Analysis/unused-ivars.m
+++ b/test/Analysis/unused-ivars.m
@@ -1,4 +1,4 @@
-// RUN: %clang_cc1 -fblocks -analyze -analyzer-check-objc-unused-ivars %s -verify
+// RUN: %clang_cc1 -fobjc-nonfragile-abi2 -fblocks -analyze -analyzer-check-objc-unused-ivars %s -verify
 
 //===--- BEGIN: Delta-debugging reduced headers. --------------------------===//
 
@@ -95,4 +95,16 @@
 
 @implementation RDar7353683
 @end
+//===----------------------------------------------------------------------===//
+// <rdar://problem/8481311> Unused bitfield ivars trigger cause weird
+// diagnostic: "Instance variable '' in class…"
+//===----------------------------------------------------------------------===//
 
+@interface RDar8481311 {
+@private
+    unsigned bitfield:1; // expected-warning {{Instance variable 'bitfield' in class 'RDar8481311' is never used}}
+}
+@end
+
+@implementation RDar8481311
+@end