diff --git a/js/src/xpconnect/src/xpccallcontext.cpp b/js/src/xpconnect/src/xpccallcontext.cpp
index 44018609fa8..5aae4ba9759 100644
--- a/js/src/xpconnect/src/xpccallcontext.cpp
+++ b/js/src/xpconnect/src/xpccallcontext.cpp
@@ -373,6 +373,7 @@ XPCCallContext::~XPCCallContext()
             NS_ASSERTION(!se[i].mInUse, "Uh, string wrapper still in use!");
         }
     }
+#endif
 
     NS_IF_RELEASE(mXPC);
 }