--- Wnn/jlib/wnnerrmsg.c.orig
+++ Wnn/jlib/wnnerrmsg.c
@@ -49,6 +49,7 @@
 /*	Version 4.0
  */
 #include <stdio.h>
+#include <string.h>
 #include "jslib.h"
 #include "commonhd.h"
 #include "wnn_os.h"
