diff --git a/src/haproxy.c b/src/haproxy.c
index 5d3d92869..d09f15c85 100644
--- a/src/haproxy.c
+++ b/src/haproxy.c
@@ -2740,7 +2740,9 @@ static void *run_thread_poll_loop(void *data)
 	list_for_each_entry(ptaf, &per_thread_alloc_list, list) {
 		if (!ptaf->fct()) {
 			ha_alert("failed to allocate resources for thread %u.\n", tid);
+#ifdef USE_THREAD
 			pthread_mutex_unlock(&init_mutex);
+#endif
 			exit(1);
 		}
 	}
@@ -2752,7 +2754,9 @@ static void *run_thread_poll_loop(void *data)
 	list_for_each_entry(ptif, &per_thread_init_list, list) {
 		if (!ptif->fct()) {
 			ha_alert("failed to initialize thread %u.\n", tid);
+#ifdef USE_THREAD
 			pthread_mutex_unlock(&init_mutex);
+#endif
 			exit(1);
 		}
 	}