Inconsistent Results When Using IFNULL

There is an inconsistency in the results when using the IFNULL function.

1. Set up table t0:

CREATE TABLE t0 (c0 BIT, c1 BIT);

INSERT INTO t0 VALUES (0, 1);

2. Use IFNULL in a SELECT query:

SELECT (IFNULL(t0.c0, t0.c1)) FROM t0;

--Result: 48

3. Store the result of COALESCE in another table t1 and SELECT FROM t1:

CREATE TABLE t1 AS (SELECT (IFNULL(t0.c0, t0.c1)) AS c0 FROM t0);

SELECT * FROM t1;

--Result: 0

See: https://dbfiddle.uk/Mf6xPcJK
The result should be consistent regardless of whether the result is directly selected or stored in another table.