Re: Help with "fatal: unable to read ...." error during GC?

[Paul Smith <paul@mad-scientist.net>]

On Wed, 2018-08-08 at 12:06 -0400, Jeff King wrote:
> I'd have expected fsck to find it, too. However, looking at the code,
> I'm not convinced that fsck is actually considering detached worktree
> heads properly, either. Try:
> 
>   git rev-list --all --reflog --objects >/dev/null
> 
> which I know checks worktrees correctly. I'd expect that to fail.
> 
> If it does, then we need to narrow down which worktree is corrupt.
> Perhaps something like:
> 
>   git worktree list |
>   while read worktree head junk; do
>         git rev-list --objects $head >/dev/null ||
>         echo "$worktree seems corrupt"
>   done

Thanks for the note!  Unhappily for me none of these operations seem to
find any actionable problems...

$ git rev-list --all --reflog --objects >/dev/null
warning: reflog of 'HEAD' references pruned commits
warning: reflog of 'HEAD' references pruned commits
warning: reflog of 'HEAD' references pruned commits
warning: reflog of 'HEAD' references pruned commits
warning: reflog of 'HEAD' references pruned commits
warning: reflog of 'HEAD' references pruned commits
warning: reflog of 'HEAD' references pruned commits
warning: reflog of 'HEAD' references pruned commits
warning: reflog of 'HEAD' references pruned commits
warning: reflog of 'HEAD' references pruned commits
$ echo $?
0

$ git worktree list | while read wt head junk; do \
  git rev-list --objects $head >/dev/null || echo "$wt seems corrupt"; \
  done
$

Just to be sure I updated the loop above to echo $wt and $head and they
were correct.  I also re-ran git gc after the above and still got the
original error output so it didn't magically fix itself :).