--- byacc-20191125/main.c.orig	Thu Jan 23 16:59:19 2020
+++ byacc-20191125/main.c	Thu Jan 23 16:59:29 2020
@@ -7,6 +7,8 @@
 #include <stdlib.h>		/* for _exit() */
 #endif
 
+#include <getopt.h>
+
 #include "defs.h"
 
 #ifdef HAVE_MKSTEMP