Different warnings for TIME and TIME(N) when @@old_mode=zero_date_time_cast

SET @@old_mode=zero_date_time_cast;

DROP TABLE IF EXISTS t1;

CREATE TABLE t1 (a TIME,b TIME(1));

INSERT INTO t1 VALUES (TIME'830:20:30',TIME'830:20:30');

SELECT TO_DAYS(a), TO_DAYS(b) FROM t1;

SHOW WARNINGS;

...

MariaDB [test]> SELECT TO_DAYS(a), TO_DAYS(b) FROM t1;

+------------+------------+

| TO_DAYS(a) | TO_DAYS(b) |

+------------+------------+

|       NULL |       NULL |

+------------+------------+

1 row in set, 1 warning (0.00 sec)

MariaDB [test]> SHOW WARNINGS;

+---------+------+--------------------------------------------+

| Level   | Code | Message                                    |

+---------+------+--------------------------------------------+

| Warning | 1264 | Out of range value for column 'a' at row 1 |

+---------+------+--------------------------------------------+

1 row in set (0.00 sec)