Re: could not freshen shared index ..../sharedindex.0000000000000000000000000000000000000000'

From: Luke Diamand <luke@diamand.org>
Date: Feb 9, 2019, 09:57 UTC
Message-ID: <CAE5ih79JYrcV9cxMBU88Hq=HHQOOyzpkq+kT2zAgDzs=ao+PMg@mail.gmail.com>
In-Reply-To: <CACsJy8CeRFyhkdohwU_KtXtgmkOzNsQPb4oKFcn+R210MpS1KA@mail.gmail.com>

On Sat, 9 Feb 2019 at 05:01, Duy Nguyen <pclouds@gmail.com> wrote:

Show 24 quoted lines

>
> On Fri, Feb 8, 2019 at 11:39 PM Luke Diamand <luke@diamand.org> wrote:
> >
> > On Fri, 8 Feb 2019 at 10:02, Duy Nguyen <pclouds@gmail.com> wrote:
> > >
> > > On Wed, Feb 06, 2019 at 10:25:25AM +0000, Luke Diamand wrote:
> > > > I've recently started seeing a lot of this message when doing a rebase:
> > > >
> > > >    warning: could not freshen shared index
> > > > '/home/ldiamand/git/dev_full/.git/worktrees/gcc8-take-2/sharedindex.0000000000000000000000000000000000000000'
> > >
> > > There are only two places in the code that could print this. The one
> > > in read_index_from() can't happen unless is_null_oid() is broken (very
> > > very unlikely).
> > >
> > > The other one is in write_locked_index() which could happen in theory
> > > but I don't understand how it got there. If you could build git, could
> > > you try this patch and see if it helps?
> >
> > They've gone away!
>
> Great! Since you seem able to reproduce this (and can build git!)
> could you try bisect to pin point the commit that causes this problem?
> That would help a lot. I think you could start maybe from v2.19.0

The first bad commit was d658196f3c4b2478ebdff638e2c3e4fb2f9cbba2.

$ git show d658196f3c4b2478ebdff638e2c3e4fb2f9cbba2
commit d658196f3c4b2478ebdff638e2c3e4fb2f9cbba2 (refs/bisect/bad)
Merge: 6b0f1d9c47 7db118303a
Author: Junio C Hamano <gitster@pobox.com>
Date:   Wed May 23 14:38:22 2018 +0900

    Merge branch 'en/unpack-trees-split-index-fix'

    The split-index feature had a long-standing and dormant bug in
    certain use of the in-core merge machinery, which has been fixed.

    * en/unpack-trees-split-index-fix:
      unpack_trees: fix breakage when o->src_index != o->dst_index

The test I'm doing is just:

1. git checkout some_tag
2. git rebase -i HEAD~5
3. Swap the top and bottom commit
4. repeat

I just chose "5" as my first wild guess, other numbers are also available.

With "5" I get 3 lots of:
   warning: could not freshen shared index
'.git/sharedindex.0000000000000000000000000000000000000000'

As far as I can tell the actual rebasing is fine.