diff --git a/src/include/lwip/netif.h b/src/include/lwip/netif.h
index 6b302bfd..77d0fb82 100644
--- a/src/include/lwip/netif.h
+++ b/src/include/lwip/netif.h
@@ -379,7 +379,7 @@ struct netif {
 #else /* LWIP_SINGLE_NETIF */
 /** The list of network interfaces. */
 extern struct netif *netif_list;
-#define NETIF_FOREACH(netif) for (netif = netif_list; netif != NULL; netif = netif->next)
+#define NETIF_FOREACH(netif) for ((netif) = netif_list; (netif) != NULL; (netif) = (netif)->next)
 #endif /* LWIP_SINGLE_NETIF */
 /** The default network interface. */
 extern struct netif *netif_default;