--- a/js/src/jsworkers.cpp
+++ b/js/src/jsworkers.cpp
@@ -25,16 +25,17 @@ js::StartOffThreadIonCompile(JSContext *
     JSRuntime *rt = cx->runtime;
     if (!rt->workerThreadState) {
         rt->workerThreadState = rt->new_<WorkerThreadState>();
         if (!rt->workerThreadState)
             return false;
         if (!rt->workerThreadState->init(rt)) {
             js_delete(rt->workerThreadState);
             rt->workerThreadState = NULL;
+            return false;
         }
     }
     WorkerThreadState &state = *cx->runtime->workerThreadState;
 
     JS_ASSERT(state.numThreads);
 
     AutoLockWorkerThreadState lock(rt);