Re: (ITS#8299) LMDB mdb_del data loss when used in a cursor (new repro)

[hyc@symas.com]

malyn@strangeGizmo.com wrote:
> Full_Name: Michael Alyn Miller
> Version: Git head
> OS: Windows 8.1 x64, NixOS 14.12 x64
> URL: ftp://ftp.openldap.org/incoming/michaelalynmiller-151103.c
> Submission from: (NULL) (96.251.78.237)
>
>
> I have a new repro of an ITS#8264-like situation, but with different input data
> and with slightly different results.  Note that ITS#8264 was fixed with the
> dataset provided in that bug; this is a different dataset and produces different
> results.
>
> The referenced test runs twice: once with mdb_cursor_del and once with mdb_del.
> Just like before, mdb_cursor_del performs correctly whereas mdb_del corrupts the
> database.  In this case, mdb_del incorrectly removes one extra key (a key
> prefixed with 04000000000000003a...), and incorrectly leaves 21 keys in place
> that should have been deleted (those keys begin with 05000000000000003a...).
> This last item is the primary difference between these two bugs.
>
> Unlike ITS#8264, you do not need to remove the database in between test runs in
> order to repro this issue, although the results are still incorrect and will
> eventually cause a bus error.

Thanks again for the excellent bug reports. Fixed now in git.

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