"fatal: reference is not a tree:" on git checkout <branch>

David Abdurachmanov· Jul 26, 2013, 09:52 UTC · lore

Hi,

Reproduce:

$ git clone https://github.com/cms-sw/cmsdist.git $ git branch -a | grep devel-gcc48 remotes/origin/IB/CMSSW_7_0_X/devel-gcc48 $ git checkout IB/CMSSW_7_0_X/devel-gcc48 fatal: reference is not a tree: IB/CMSSW_7_0_X/devel-gcc48

It has stopped to work with the last pull request. All the references on Google talk about submodules, which I don't use. Any ideas what could be causing this issue?

You can get into detached state by: $ git checkout origin/IB/CMSSW_7_0_X/devel-gcc48

You also can checkout a branch by doing:
$ git clone -b IB/CMSSW_7_0_X/devel-gcc48 https://github.com/cms-sw/cmsdist.git
$ git branch
* IB/CMSSW_7_0_X/devel-gcc48

Thanks, david

Duy Nguyen· Jul 26, 2013, 11:46 UTC · re: David Abdurachmanov · lore

Re: "fatal: reference is not a tree:" on git checkout <branch>

On Fri, Jul 26, 2013 at 4:52 PM, David Abdurachmanov <david.abd@gmail.com> wrote:

Show 13 quoted lines

> Hi,
>
> Reproduce:
>
> $ git clone https://github.com/cms-sw/cmsdist.git
> $ git branch -a | grep devel-gcc48
> remotes/origin/IB/CMSSW_7_0_X/devel-gcc48
> $ git checkout IB/CMSSW_7_0_X/devel-gcc48
> fatal: reference is not a tree: IB/CMSSW_7_0_X/devel-gcc48
>
> It has stopped to work with the last pull request. All the references on Google
> talk about submodules, which I don't use. Any ideas what could be causing this
> issue?

"Bad" naming. It interprets the branch name as something-gHEX like the output from git-describe. Coincidently "cc48" is an umambiguous short sha-1. check_tracking_name, which prefix "origin/" in, never has a chance to run.

We should probably check in get_describe_name() that the returned value is a commit or a tag, but that doesn't really solve the problem. I think check_tracking_name should have higher priority than get_describe_name()..

-- 
Duy