Index: sys/netinet/tcp_output.c
===================================================================
--- sys/netinet/tcp_output.c
+++ sys/netinet/tcp_output.c
@@ -1652,7 +1652,7 @@
 int
 tcp_addoptions(struct tcpopt *to, u_char *optp)
 {
-	u_int mask, optlen = 0;
+	u_int32_t mask, optlen = 0;
 
 	for (mask = 1; mask < TOF_MAXOPT; mask <<= 1) {
 		if ((to->to_flags & mask) != mask)
Index: sys/netinet/tcp_var.h
===================================================================
--- sys/netinet/tcp_var.h
+++ sys/netinet/tcp_var.h
@@ -364,7 +364,7 @@
  * options in tcp_addoptions.
  */
 struct tcpopt {
-	u_int64_t	to_flags;	/* which options are present */
+	u_int32_t	to_flags;	/* which options are present */
 #define	TOF_MSS		0x0001		/* maximum segment size */
 #define	TOF_SCALE	0x0002		/* window scaling */
 #define	TOF_SACKPERM	0x0004		/* SACK permitted */