Re: Bug in "revision.c: --all adds HEAD from all worktrees" ?

[Luke Diamand <luke@diamand.org>]

On 13 November 2017 at 19:51, Luke Diamand <luke@diamand.org> wrote:
> Hi!
>
> I think there may be a regression caused by this change which means
> that "git fetch origin" doesn't work:
>
> commit d0c39a49ccb5dfe7feba4325c3374d99ab123c59 (refs/bisect/bad)
> Author: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
> Date:   Wed Aug 23 19:36:59 2017 +0700
>
>     revision.c: --all adds HEAD from all worktrees
>
> $ git fetch origin
> fatal: bad object HEAD
> error: ssh://my_remote_host/reponame did not send all necessary objects
>
> I used git bisect to find the problem, and it seems pretty consistent.
> "git fetch" with the previous revision works fine.
>
> FWIW, I've got a lot of git worktrees associated with this repo, so
> that may be why it's failing. The remote repo is actually a git-p4
> clone, so HEAD there actually ends up pointing at
> refs/remote/p4/master.
>
> Thanks,
> Luke

Quite a few of the worktrees have expired - their head revision has
been GC'd and no longer points to anything sensible
(gc.worktreePruneExpire). The function other_head_refs() in worktree.c
bails out if there's an error, which I think is the problem. I wonder
if it should instead just report something and then keep going.