charset.c:

  SHOW CHARACTER SET now displays "1" in mb_maxlen even if a charset is not loaded yet

mysys/charset.c

@@ -215,6 +215,7 @@ static void simple_cs_copy_data(CHARSET_INFO *to, CHARSET_INFO *from)
 					     MYF(MY_WME));
     create_fromuni(to);
   }
+  to->mbmaxlen= 1;
 }