Index: lib/CodeGen/BackendUtil.cpp
===================================================================
--- lib/CodeGen/BackendUtil.cpp
+++ lib/CodeGen/BackendUtil.cpp
@@ -569,7 +569,7 @@
   // Add ObjC ARC final-cleanup optimizations. This is done as part of the
   // "codegen" passes so that it isn't run multiple times when there is
   // inlining happening.
-  if (LangOpts.ObjCAutoRefCount &&
+  if (TheModule->getModuleFlag("Objective-C ARC") &&
       CodeGenOpts.OptimizationLevel > 0)
     PM->add(createObjCARCContractPass());
 
Index: lib/CodeGen/CGObjCMac.cpp
===================================================================
--- lib/CodeGen/CGObjCMac.cpp
+++ lib/CodeGen/CGObjCMac.cpp
@@ -4284,6 +4284,12 @@
     }
   }
 
+  // Add ObjCAutoRefCount as a module flag
+  if (CGM.getLangOpts().ObjCAutoRefCount) {
+    Mod.addModuleFlag(llvm::Module::Error,
+                      "Objective-C ARC", 1u);
+  }
+
   // Indicate whether we're compiling this to run on a simulator.
   const llvm::Triple &Triple = CGM.getTarget().getTriple();
   if (Triple.isiOS() &&
Index: test/CodeGen/arc-passes.m
===================================================================
--- /dev/null
+++ test/CodeGen/arc-passes.m
@@ -0,0 +1,12 @@
+// RUN: %clang_cc1 -triple x86_64-apple-darwin10 -fobjc-arc -emit-llvm %s -o - | FileCheck %s
+// RUN: %clang_cc1 -triple x86_64-apple-darwin10 -emit-llvm %s -o - | FileCheck %s -check-prefix=NO-ARC
+// RUN: %clang_cc1 -triple x86_64-apple-darwin10 -fobjc-arc -emit-obj -O3 %s -o /dev/null -mllvm -debug-pass=Arguments 2>&1 | FileCheck %s -check-prefix=ARC-PASS
+// RUN: %clang_cc1 -triple x86_64-apple-darwin10 -emit-obj -O3 %s -o /dev/null -mllvm -debug-pass=Arguments 2>&1 | FileCheck %s -check-prefix=NO-ARC-PASS
+
+// CHECK: !{i32 1, !"Objective-C ARC", i32 1}
+// NO-ARC-NOT: !{i32 1, !"Objective-C ARC", i32 1}
+// ARC-PASS: -objc-arc-contract
+// NO-ARC-PASS-NOT: -objc-arc-contract
+
+void test() {
+}