diff --git a/src/task.c b/src/task.c
index cde958e83..8eabb4633 100644
--- a/src/task.c
+++ b/src/task.c
@@ -395,6 +395,8 @@ void wake_expired_tasks()
 
 					if (new_tid == tid)
 						continue;
+
+					ASSUME(new_tid < MAX_THREADS);
 					if (ha_thread_ctx[new_tid].rq_total * 2 < th_ctx->rq_total) {
 						int cur_state;
 						do {