--- sys/netinet/tcp_fastopen.c.orig	2016-08-04 15:04:22.000000000 -0600
+++ sys/netinet/tcp_fastopen.c	2016-08-04 15:03:57.000000000 -0600
@@ -111,6 +111,7 @@
 #include <sys/socketvar.h>
 #include <sys/sysctl.h>
 #include <sys/systm.h>
+#include <sys/socket.h>
 
 #include <crypto/siphash/siphash.h>