+ /* if the head of all_threads is removed during
+ * gc_stop_the_world, we may take a second trip through the
+ * list and end up counting twice as many threads to wait for
+ * as actually exist */
+ if(p->state!=STATE_RUNNING) continue;
+ countdown_to_gc++;
+ p->state=STATE_STOPPING;
+ /* Note no return value check from kill(). If the
+ * thread had been reaped already, we kill it and
+ * increment countdown_to_gc anyway. This is to avoid
+ * complicating the logic in destroy_thread, which would
+ * otherwise have to know whether the thread died before or
+ * after it was killed
+ */
+ kill(p->pid,SIG_STOP_FOR_GC);