--- src/include/buffer.h.orig	2016-04-28 18:46:27.769231116 +0200
+++ src/include/buffer.h	2016-04-28 18:47:36.872928731 +0200
@@ -22,6 +22,8 @@
 # define _XOPEN_SOURCE 600
 #endif
 
+#include <sys/cdefs.h>
+
 #include <stdio.h>
 #include <sys/uio.h>