diff --git a/bridge/fdb.c b/bridge/fdb.c
--- a/bridge/fdb.c
+++ b/bridge/fdb.c
@@ -31,7 +31,7 @@

 static unsigned int filter_index, filter_vlan, filter_state;

-json_writer_t *jw_global;
+static json_writer_t *jw_global;

 static void usage(void)
 {
diff --git a/ip/ipmroute.c b/ip/ipmroute.c
--- a/ip/ipmroute.c
+++ b/ip/ipmroute.c
@@ -44,7 +44,7 @@
        exit(-1);
 }

-struct rtfilter {
+static struct rtfilter {
        int tb;
        int af;
        int iif;
diff --git a/ip/xfrm_monitor.c b/ip/xfrm_monitor.c
--- a/ip/xfrm_monitor.c
+++ b/ip/xfrm_monitor.c
@@ -34,7 +34,7 @@
 #include "ip_common.h"

 static void usage(void) __attribute__((noreturn));
-int listen_all_nsid;
+static int listen_all_nsid;

 static void usage(void)
 {