diff --git a/kdc/kerberos4.c b/kdc/kerberos4.c
index 8b35e8c61..81a3bd5a2 100644
--- a/kdc/kerberos4.c
+++ b/kdc/kerberos4.c
@@ -319,7 +319,7 @@ do_version4(unsigned char *buf,
 	break;
     }
     case AUTH_MSG_APPL_REQUEST: {
-	_krb5_krb_auth_data ad;
+	struct _krb5_krb_auth_data ad;
 	int8_t kvno;
 	int8_t ticket_len;
 	int8_t req_len;