diff -u -r ../libevent-release-2.1.8-stable/evutil.c ./evutil.c
--- ../libevent-release-2.1.8-stable/evutil.c	2017-01-26 00:37:15.000000000 +0100
+++ ./evutil.c	2017-07-07 01:04:14.746540880 +0200
@@ -47,6 +47,7 @@
 #include <sys/socket.h>
 #endif
 #ifdef EVENT__HAVE_UNISTD_H
+#define __USE_GNU 1 /* For pipe2(). */
 #include <unistd.h>
 #endif
 #ifdef EVENT__HAVE_FCNTL_H
