CTE with overflow of integer type returns wrong results

MariaDB [test]> WITH RECURSIVE qn AS (SELECT 1 AS a FROM dual UNION SELECT a*2000 FROM qn WHERE a<10000000000000000000) SELECT count(*) FROM qn;

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

| count(*) |

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

|        4 |

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

1 row in set (0.002 sec)

MariaDB [test]> select version();

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

| version()            |

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

| 10.3.8-MariaDB-debug |

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

1 row in set (0.000 sec)

MariaDB [test]> WITH RECURSIVE qn AS (SELECT 1 AS a FROM dual UNION SELECT a*2000 FROM qn WHERE a<10000000000000000000) SELECT count(*) FROM qn;

ERROR 1690 (22003): BIGINT value is out of range in '`qn`.`a` * 2000'

MariaDB [test]> select version();

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

| version()             |

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

| 10.2.16-MariaDB-debug |

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

1 row in set (0.00 sec)