Comment 2 for bug 1023404

Hello,
Thanks for verifying the problem. I see that the 5.5 branch is fixed.
 I dont understand when changes would be made on the maria trunk,
since the bug exists there as well.
Rich Prohaska

On Wed, Jul 11, 2012 at 10:14 AM, Sergei <email address hidden> wrote:
> Thanks! It must be a result of a merge - the initialization code was
> moved down in mysql-5.5, and when merging it into mariadb bzr decided to
> keep both copies for some reason. Sorry for this!
>
> ** Changed in: maria
> Status: New => Confirmed
>
> ** Changed in: maria
> Importance: Undecided => High
>
> --
> You received this bug notification because you are subscribed to the bug
> report.
> https://bugs.launchpad.net/bugs/1023404
>
> Title:
> problems with savepoints and tokudb with 5.5
>
> Status in Maria:
> Confirmed
>
> Bug description:
> We observed a problem with savepoints in Mariadb 5.5.25. The problem
> at the SQL layer is that a "rollback to savepoint" statement would get
> an error after the savepoint was created. The problem was caused by
> the savepoint name in the savepoint stack getting overwritten by the
> handlerton savepoint_set method.
>
> We believe that the handler savepoint_offset initialization is WRONG.
> The ha_initialize_handlerton function executes the savepoint
> initialization twice, which breaks the contract spec'ed in the
> handler.h file.
>
> Suppose that savepoint_alloc_size = 0, and hton->savepoint_offset = 32.
> After the first savepoint init code is executed at line 504, savepoint_alloc_size = 32 and hton->savepoint_offset = 0.
> After the second savepoint int code is executed at line 530, savepoint_alloc_size = 32 and hton->savepoint_offset = 32.
> So, the handlerton's savepoint is outside of the memory allocated for the savepoint state.
>
> Our fix is here: lp:~prohaska7/maria/5.5-savepoint-offset-fix
>
> To manage notifications about this bug go to:
> https://bugs.launchpad.net/maria/+bug/1023404/+subscriptions