[#MDEV-30298] '-0.' changed to '-0.0001' after adding DISTINCT [10.5.1,10.11.1]

Description:
In theory, the result of sql2(DISTINCT) ⊆ the result of sql1:

SELECT -f2 AS f1 FROM (SELECT (BINARY c1) AS f2 FROM t) AS t1; -- sql1

SELECT -f2 AS f1 FROM (SELECT DISTINCT (BINARY c1) AS f2 FROM t) AS t1; -- sql2

However, the value '-0.' changed to '-0.0001' after adding DISTINCT, seems like a logical bug:

mysql> select version();

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

| version()                               |

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

| 10.11.1-MariaDB-1:10.11.1+maria~ubu2204 |

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

1 row in set (0.00 sec)

mysql> SELECT -f2 AS f1 FROM (SELECT (BINARY c1) AS f2 FROM t) AS t1; -- sql1

+------+

| f1   |

+------+

|  -0. |

+------+

1 row in set (0.00 sec)

mysql> SELECT -f2 AS f1 FROM (SELECT DISTINCT (BINARY c1) AS f2 FROM t) AS t1; -- sql2

+---------+

| f1      |

+---------+

| -0.0001 |

+---------+

1 row in set (0.00 sec)

drop table if exists t;

CREATE TABLE t (c1 DOUBLE);

INSERT INTO t VALUES (0.0001);

SELECT -f2 AS f1 FROM (SELECT (BINARY c1) AS f2 FROM t) AS t1; -- sql1

SELECT -f2 AS f1 FROM (SELECT DISTINCT (BINARY c1) AS f2 FROM t) AS t1; -- sql2

Hope these can be helpful for your debugging:
1. The bug cannot be reproduced after removing BINARY;
2. We look for the first version of the bug in all docker images (with format x.x.x) of https://hub.docker.com/_/mariadb/tags
We found that the bug first occurred in mariadb:10.5.1, it cannot be reproduced in mariadb:10.4.27 (we can't find more intermediate versions in dockerhub):

MariaDB [TEST]> select version();

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

| version()                            |

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

| 10.5.1-MariaDB-1:10.5.1+maria~bionic |

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

1 row in set (0.000 sec)

MariaDB [TEST]> SELECT -f2 AS f1 FROM (SELECT (BINARY c1) AS f2 FROM t) AS t1; -- sql1

+------+

| f1   |

+------+

|  -0. |

+------+

1 row in set (0.000 sec)

MariaDB [TEST]> SELECT -f2 AS f1 FROM (SELECT DISTINCT (BINARY c1) AS f2 FROM t) AS t1; -- sql2

+---------+

| f1      |

+---------+

| -0.0001 |

+---------+

1 row in set (0.000 sec)

MariaDB [TEST]> select version();

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

| version()                               |

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

| 10.4.27-MariaDB-1:10.4.27+maria~ubu2004 |

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

1 row in set (0.000 sec)

MariaDB [TEST]> SELECT -f2 AS f1 FROM (SELECT (BINARY c1) AS f2 FROM t) AS t1; -- sql1

+---------+

| f1      |

+---------+

| -0.0001 |

+---------+

1 row in set (0.000 sec)

MariaDB [TEST]> SELECT -f2 AS f1 FROM (SELECT DISTINCT (BINARY c1) AS f2 FROM t) AS t1; -- sql2

+---------+

| f1      |

+---------+

| -0.0001 |

+---------+

1 row in set (0.000 sec)

[MDEV-30298] '-0.' changed to '-0.0001' after adding DISTINCT [10.5.1,10.11.1] Created: 2022-12-25 Updated: 2023-11-28
Status:	Confirmed
Project:	MariaDB Server
Component/s:	Optimizer
Affects Version/s:	10.5.1, 10.11.1, 10.5, 10.6, 10.7, 10.8, 10.9, 10.10
Fix Version/s:	10.5, 10.6

[MDEV-30298] '-0.' changed to '-0.0001' after adding DISTINCT [10.5.1,10.11.1] Created: 2022-12-25 Updated: 2023-11-28