From: Junio C Hamano Date: Fri, 08 Jun 2007 10:33:40 GMT Subject: Re: fatal: ambiguous argument 'HEAD': unknown revision or path not in the working tree. Message-ID: <7vfy52ka63.fsf@assigned-by-dhcp.cox.net> In-Reply-To: <20070608102113.GB2335@cip.informatik.uni-erlangen.de> Thomas Glanzmann writes: > I see it. Last line. I tried to clone from a repository which itself had a > detached HEAD. Could that be the problem? Ah, our mails crossed. There is no reason to forbid cloning of a repository whose HEAD is detached, but detached HEAD is a relatively recent invention, and I would not be surprised if that was indeed the breakage, nor nobody has hit this so far. It's sufficiently late here so I do not think I would be able to take a look at it tonight, though. Sorry. Just in case you need unblocking (although I think you know how already), you should be able to continue with: $ git rev-parse v2.6.20^0 >.git/HEAD $ git read-tree HEAD $ git checkout-index -f -q -u -a That would give you a normal detached state at v2.6.20; you should be able to come back to your branches with usual "git checkout".