diff --git a/sys/kern/kern_thr.c b/sys/kern/kern_thr.c
--- a/sys/kern/kern_thr.c
+++ b/sys/kern/kern_thr.c
@@ -315,8 +315,8 @@
 
 	/* Signal userland that it can free the stack. */
 	if ((void *)uap->state != NULL) {
-		suword_lwpid(uap->state, 1);
-		kern_umtx_wake(td, uap->state, INT_MAX, 0);
+		(void)suword_lwpid(uap->state, 1);
+		(void)kern_umtx_wake(td, uap->state, INT_MAX, 0);
 	}
 
 	return (kern_thr_exit(td));