Comment # 3 on bug 52669 from Patrick Ohly

Fix in libsynthesis master branch:

commit 7b636720a46699e82c7caadf4550a0cd23571465
Author: Patrick Ohly <patrick.ohly@intel.com>
Date:   Wed Jul 2 13:12:58 2014 +0200

    fix asynchronous item update

    gcc 4.9 found a flaw in the code path for updating an item when the DB
    detects a duplicate: some variables where not preserved across
    function restarts.

And from the SyncEvolution master branch:

commit d06e40d365b5f9a213af3938b1dac78ae18b1b85
Author: Patrick Ohly <patrick.ohly@intel.com>
Date:   Mon Jul 21 13:40:29 2014 +0200

    engine: enable batching by default (FDO #52669)

    This reverts commit c435e937cd406e904c437eec51a32a6ec6163102.

    Commit 7b636720a in libsynthesis fixes an unitialized memory read in
    the asynchronous item update code path.

    Testing confirms that we can now used batched writes reliably with EDS
    (the only backend currently supporting asynchronous writes +
    batching), so this change enables it again also for local and
    SyncEvolution<->SyncEvolution sync (with asynchronous execution of
    contact add/update overlapped with SyncML message exchanges) and other
    SyncML syncs (with changes combined into batches and executed at the
    end of each message).