Fixed missing cast of arg to my_mbcharlen

client/mysqltest.cc

@@ -5721,7 +5721,7 @@ int read_line(char *buf, int size)
       /* Could be a multibyte character */
       /* This code is based on the code in "sql_load.cc" */
 #ifdef USE_MB
-      int charlen = my_mbcharlen(charset_info, c);
+      int charlen = my_mbcharlen(charset_info, (unsigned char) c);
       /* We give up if multibyte character is started but not */
       /* completed before we pass buf_end */
       if ((charlen > 1) && (p + charlen) <= buf_end)