It would not be good to edit line 172 as it is an error routine:

if ($debug) {
print 'query: '. $query .'error:'. mysql_error($active_db) .'';
}

if (!mysql_errno($active_db)) {
return $result;
}
else {
trigger_error(check_plain(mysql_error($active_db) ."\nquery: ". $query), E_USER_WARNING);
return FALSE;
}
}

The trigger_error is line 172.