diff --git a/sys/boot/common/panic.c b/sys/boot/common/panic.c
index 181c4c71507..6e4c76d0e03 100644
--- a/sys/boot/common/panic.c
+++ b/sys/boot/common/panic.c
@@ -39,6 +39,8 @@ __FBSDID("$FreeBSD$");
 #include <stand.h>
 #include <machine/stdarg.h>
 
+extern void exit(int) __dead2;
+
 void
 panic(const char *fmt,...)
 {