diff --git a/sys/netinet/tcp_output.c b/sys/netinet/tcp_output.c
index 621b524734eb..aa7f58f6bddc 100644
--- a/sys/netinet/tcp_output.c
+++ b/sys/netinet/tcp_output.c
@@ -883,7 +883,7 @@ tcp_output(struct tcpcb *tp)
 	 * Trace.
 	 */
 	if (so->so_options & SO_DEBUG) {
-		u_short save;
+		u_short save = 0;
 #ifdef INET6
 		if (!isipv6)
 #endif