diff --git a/lib/Serialization/ModuleManager.cpp b/lib/Serialization/ModuleManager.cpp
index 1fc82dd..b90ecc0 100644
--- a/lib/Serialization/ModuleManager.cpp
+++ b/lib/Serialization/ModuleManager.cpp
@@ -332,8 +332,7 @@
         break;
 
       // Pop the next module off the stack.
-      NextModule = State->Stack.back();
-      State->Stack.pop_back();
+      NextModule = State->Stack.pop_back_val();
     } while (true);
   }