Subquery is not allowed as the lower FOR loop bound

DELIMITER $$

SET @v=0;

FOR a IN (SELECT 1) .. 3 DO SET @v = @v + a; END FOR;

$$

ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near '.. 3 DO SET @v = @v + a; END FOR' at line 1

DELIMITER $$

SET @v=0;

FOR a IN 1 ..(SELECT 3) DO SET @v = @v + a; END FOR;

SELECT @v;

$$

+------+

| @v   |

+------+

|    6 |

+------+