diff --git a/ip/ipmroute.c b/ip/ipmroute.c
index 6cf91fe9..3537bdf4 100644
--- a/ip/ipmroute.c
+++ b/ip/ipmroute.c
@@ -44,7 +44,7 @@ static void usage(void)
 	exit(-1);
 }
 
-struct rtfilter {
+static struct rtfilter {
 	int tb;
 	int af;
 	int iif;