diff --git a/sys/netinet/tcp.h b/sys/netinet/tcp.h
--- a/sys/netinet/tcp.h
+++ b/sys/netinet/tcp.h
@@ -80,18 +80,23 @@
 };
 
 static __inline uint16_t
-tcp_get_flags(const struct tcphdr *th)
+__tcp_get_flags(const struct tcphdr *th)
 {
-        return (((uint16_t)th->th_x2 << 8) | th->th_flags);
+	return (((uint16_t)th->th_x2 << 8) | th->th_flags);
 }
 
 static __inline void
-tcp_set_flags(struct tcphdr *th, uint16_t flags)
+__tcp_set_flags(struct tcphdr *th, uint16_t flags)
 {
-        th->th_x2    = (flags >> 8) & 0x0f;
-        th->th_flags = flags & 0xff;
+	th->th_x2    = (flags >> 8) & 0x0f;
+	th->th_flags = flags & 0xff;
 }
 
+#ifdef _KERNEL
+#define tcp_get_flags __tcp_get_flags
+#define tcp_set_flags __tcp_set_flags
+#endif
+
 #define	PADTCPOLEN(len)		((((len) / 4) + !!((len) % 4)) * 4)
 
 #define	TCPOPT_EOL		0