diff --git a/src/include/lwip/apps/mdns_opts.h b/src/include/lwip/apps/mdns_opts.h
index 710911fc..310ec38a 100644
--- a/src/include/lwip/apps/mdns_opts.h
+++ b/src/include/lwip/apps/mdns_opts.h
@@ -32,6 +32,9 @@
 
 #ifndef LWIP_HDR_APPS_MDNS_OPTS_H
 #define	LWIP_HDR_APPS_MDNS_OPTS_H
+
+#include "lwip/opt.h"
+
 /**
  * @defgroup mdns_opts Options
  * @ingroup mdns