diff --git a/mk/config.h.in b/mk/config.h.in
index f993d5461cef755a5dbf5ae4b0149b51b2d6f275..afad35d25c407700fc97357e439976b21bf4dbb8 100644
--- a/mk/config.h.in
+++ b/mk/config.h.in
@@ -171,6 +171,9 @@
 /* Define if you have the <memory.h> header file.  */
 #undef HAVE_MEMORY_H
 
+/* Define if you have the <netinet/tcp.h> header file.  */
+#undef HAVE_NETINET_TCP_H
+
 /* Define if you have the <nlist.h> header file.  */
 #undef HAVE_NLIST_H