> ------------------------------------------------------------
> revno: 2852.12.6
> tags: clone-5.1.35-build, mysql-5.1.35
> revision-id: gshchepa@mysql.com-20090513075139-g50shsfjaf1dstdn
> parent: joerg@mysql.com-20090508190407-ymqxmp6daeta6fdj
> committer: Gleb Shchepa <gshchepa@mysql.com>
> branch nick: mysql-5.1
> timestamp: Wed 2009-05-13 12:51:39 +0500
> message:
>   Bug #44290: explain crashes for subquery with distinct in
>               SQL_SELECT::test_quick_select
>   
>   The crash was caused by an incomplete cleanup of JOIN_TAB::select
>   during the filesort of rows for GROUP BY clause inside a subquery.
>   Queries where a quick index access is replaced with filesort was
>   was affected. For example:
>   
>     SELECT 1 FROM
>       (SELECT COUNT(DISTINCT c1) FROM t1
>          WHERE c2 IN (1, 1) AND c3 = 2 GROUP BY c2) x
>   
>   Quick index access related data in the SQL_SELECT::test_quick_select
>   function was inconsistent after an incomplete cleanup.
>   This function has been completed to prevent crashes in the
>   SQL_SELECT::test_quick_select function.