--- hxnum.c.orig 2016-03-20 16:18:47.815855780 +0100
+++ hxnum.c 2016-03-20 16:19:40.197200923 +0100
@@ -29,6 +29,7 @@
#endif
#include <stdlib.h>
#include <assert.h>
+#include <getopt.h>
#include "export.h"
#include "types.e"
#include "class.e"