diff --git a/sys/kern/kern_event.c b/sys/kern/kern_event.c
index 752caa4b76c5..ffdba2d6ee30 100644
--- a/sys/kern/kern_event.c
+++ b/sys/kern/kern_event.c
@@ -887,6 +887,7 @@ kern_kqueue(struct thread *td, int flags, struct filecaps *fcaps)
 	return (0);
 }
 
+#ifdef KTRACE
 static size_t
 kev_iovlen(int n, u_int kgio)
 {
@@ -895,6 +896,7 @@ kev_iovlen(int n, u_int kgio)
 		return (kgio);
 	return (n * sizeof(struct kevent));
 }
+#endif
 
 #ifndef _SYS_SYSPROTO_H_
 struct kevent_args {