--- config.h.in.orig	2016-10-05 14:33:57 UTC
+++ config.h.in
@@ -24,6 +24,9 @@
 /* Define to 1 if you have the <expat.h> header file. */
 #undef HAVE_EXPAT_H
 
+/* Is this a BSDSUniX system? */
+#undef HAVE_BSDSUNIX
+
 /* Is this a FreeBSD system? */
 #undef HAVE_FREEBSD