Wrong VIEW column data type for COALESCE(int_column)

DROP TABLE IF EXISTS t1;

CREATE TABLE t1 (a INT);

CREATE OR REPLACE VIEW v1 AS SELECT COALESCE(a) FROM t1;

DESCRIBE v1;

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

| Field       | Type       | Null | Key | Default | Extra |

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

| COALESCE(a) | bigint(11) | YES  |     | NULL    |       |

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