$NetBSD$

--- ylwrap.amd.orig	2014-10-30 14:37:46.000000000 +0000
+++ ylwrap.amd
@@ -173,7 +173,7 @@ case "$prog" in
 	flags="-P${prefix}"
 	out="mv lex.$prefix.c lex.yy.c"
 	;;
-yacc|bison)
+*yacc|*bison)
 	flags="-p $prefix";;
 esac