AVG over a field exported from an inner subquery saturates instead of returning the exact one-row value

the inner derived table contributes exactly one row with constant `663914376`, so `AVG(subq0.c2) OVER ()` must be the exact one-row average `663914376.0000`. MariaDB instead saturates that result to `99999999.9999`.

CREATE TABLE t3(c0 VARCHAR(100) NOT NULL) ENGINE=MyISAM;

INSERT INTO t3 VALUES ('802877023');

SELECT DISTINCTROW AVG(subq0.c2) OVER (), t3.c0
FROM t3,
(SELECT 663914376 AS c2 FROM t3) AS subq0; – Expected correct result: 663914376.0000 | 802877023 – actual Wrong result: 99999999.9999 | 802877023