From: Junio C Hamano <gitster@pobox.com>
Date: Fri, 08 Jun 2007 10:15:54 GMT
Subject: Re: fatal: ambiguous argument 'HEAD': unknown revision or path not in the working tree.
Message-ID: <7vodjqkazp.fsf@assigned-by-dhcp.cox.net>
In-Reply-To: <20070608100831.GA2335@cip.informatik.uni-erlangen.de>

Thomas Glanzmann <thomas@glanzmann.de> writes:

> Hello,
>
>         (s017241) [/usr/src/linux-2.6] git checkout v2.6.20
>         warning: You appear to be on a branch yet to be born.
>         warning: Forcing checkout of v2.6.20.
>         fatal: ambiguous argument 'HEAD': unknown revision or path not in the working tree.
>         Use '--' to separate paths from revisions
>         Cannot detach HEAD
>
> (s017241) [/usr/src/linux-2.6] git version
> git version 1.5.2.1
>
> what is going wrong here?

Perhaps repository was set up in an unusual way by hand
(i.e. not by a clone), such that:

 1. you have HEAD pointing at a branch (e.g. 'refs/heads/master'),
 2. which does _not_ exist yet (i.e. no 'refs/heads/master'),
 3. yet you have a tag that you can try to detach your HEAD to (e.g. v2.6.20).

... well that was my initial guess, but even after setting up such a
funny repository by hand, I cannot seem to reproduce it.