return list_empty(&q->queue_head); 
return 1; 
int elv_queue_empty(request_queue_t *q){	elevator_t *e = q->elevator;	if (e->ops->elevator_queue_empty_fn)		return e->ops->elevator_queue_empty_fn(q);	return list_empty(&q->queue_head);}
10457	/local/tlutelli/issta_data/temp/c/2005_temp/2005/10457/8922e16cf6269e668123acb1ae1fdc62b7a3a4fc/elevator.c/buggy/drivers/block/elevator.c