--- a/js/src/jstracer.cpp
+++ b/js/src/jstracer.cpp
@@ -2345,17 +2345,23 @@ TraceRecorder::TraceRecorder(JSContext* 
 
     if (fragment == fragment->root) {
         /*
          * We poll the operation callback request flag. It is updated asynchronously whenever
          * the callback is to be invoked. We can use w.nameImmpNonGC here as JIT-ed code is per
          * thread and cannot outlive the corresponding JSThreadData.
          */
         w.comment("begin-interruptFlags-check");
-        LIns* flagptr = w.nameImmpNonGC((void *) &JS_THREAD_DATA(cx)->interruptFlags);
+        /* FIXME: See bug 621140 for moving interruptCounter to the compartment. */
+#ifdef JS_THREADSAFE
+        void *interrupt = (void*) &cx->runtime->interruptCounter;
+#else
+        void *interrupt = (void*) &JS_THREAD_DATA(cx)->interruptFlags;
+#endif
+        LIns* flagptr = w.nameImmpNonGC(interrupt);
         LIns* x = w.ldiVolatile(flagptr);
         guard(true, w.eqi0(x), TIMEOUT_EXIT);
         w.comment("end-interruptFlags-check");
 
         /*
          * Count the number of iterations run by a trace, so that we can blacklist if
          * the trace runs too few iterations to be worthwhile. Do this only if the methodjit
          * is on--otherwise we must try to trace as much as possible.