diff --git a/usr.sbin/gssd/gssd.c b/usr.sbin/gssd/gssd.c
index 46f7c6da09c9..1da5071c02ed 100644
--- a/usr.sbin/gssd/gssd.c
+++ b/usr.sbin/gssd/gssd.c
@@ -42,6 +42,7 @@ __FBSDID("$FreeBSD$");
 #include <krb5.h>
 #endif
 #include <pwd.h>
+#include <stdarg.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>