CAST(char_col AS DOUBLE) prints redundant spaces in a warning

CREATE OR REPLACE TABLE t1 (a CHAR(5) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci);

INSERT INTO t1 VALUES ('1x'), ('x');

SELECT a,CAST(a AS DOUBLE) FROM t1 ORDER BY a;

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

| a    | CAST(a AS DOUBLE) |

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

| 1x   |                 1 |

| x    |                 0 |

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

SHOW WARNINGS;

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

| Level   | Code | Message                                                  |

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

| Warning | 1292 | Truncated incorrect DOUBLE value: '1x                  ' |

| Warning | 1292 | Truncated incorrect DOUBLE value: 'x                   ' |

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