Re: Antw: [EXT] Re: bug in "git fsck"?

From: René Scharfe <l.s.r@web.de>
Date: Jul 6, 2021, 14:25 UTC
Message-ID: <fcfd0401-df5b-15ec-29c4-74d2903274cd@web.de>
In-Reply-To: <60E40275020000A1000422F7@gwsmtp.uni-regensburg.de>

Am 06.07.21 um 09:12 schrieb Ulrich Windl:

Show 30 quoted lines

>>>> René Scharfe <l.s.r@web.de> schrieb am 05.07.2021 um 16:44 in Nachricht
> <77655a4e-8c39-5ccc-71af-d2d8684bf208@web.de>:
>> Am 05.07.21 um 09:42 schrieb Ulrich Windl:
>>>> You *can* overwrite them using "git branch --force foo" and then
>>>> "git branch -d foo" works.
>>>
>>> Would it be OK to force the branch to any commit (e.g.: "master"), relying
>
>> on
>>> the fact that any reference (read: "master") to that commit will prevent
>> actual
>>> removal of the commit?
>>
>> Yes, any valid commit would do.  This turns dangling branches into
>> normal delete-able ones.  Other branches are unaffected.
>
> OK, but either it does not work, or I did not understand what to do:
>
>> git branch --force bitmap-generic
> fatal: Not a valid object name: 'bitmap-generic'.
>> git fsck
> Checking object directories: 100% (256/256), done.
> Checking objects: 100% (173/173), done.
> notice: HEAD points to an unborn branch (bitmap-generic)
> dangling blob 0458be7cf03f35be365c819afe0104ff3c178ca0
> dangling blob 3000d29f0a652f3f7ed25572cac9969b90adeca5
> dangling commit 90e8531086d3efaeefdf6c8d39b6782e49dd2a0d
> dangling commit b598195f859106662bde746f391a7df9162231e9
> dangling tree fb4866ab5cc2f0c34a63334b90550ef7199a2098
> ...

First: Please make backups.

Here's what works for me.  First reproducing the error:

   $ echo aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa >.git/refs/heads/broken
   $ git branch --delete --force broken
   error: Couldn't look up commit object for 'refs/heads/broken'

Now I have a broken branch that I cannot delete. We should be on the same page now.

   $ git branch
     broken
   * master

So I'm on master, a valid branch.

   $ git branch --force broken

Now the broken branch is overwritten and points to the same commit as master.

   $ git branch --delete broken
   Deleted branch broken (was 83d267b).

And now it's gone.

René