Re: How do I undo a fast-forward merge safely?

From: Jakub Narebski <jnareb@gmail.com>
Date: Feb 22, 2009, 19:54 UTC
Message-ID: <m3fxi6s0vu.fsf@localhost.localdomain>
In-Reply-To: <e38bce640902221115o2dd1c63dv6f7acc374b48d418@mail.gmail.com>

Brent Goodrick <bgoodr@gmail.com> writes:

Show 5 quoted lines

> I had done a git merge --no-commit <source_branch> operation, but that
> bit me because I mistakingly concluded that --no-commit would prevent
> any type of automatic operation, but apparently a fast-forward
> occurred.  I should have used the --no-ff option? How do I get my
> target branch back to where it was before the bad merge?

[...]

> So, what operations, rebase, reset, etc, do I need to do to get this
> repo back to where it was right before the fast-forward?

Each 'large' operation sets ORIG_HEAD

  $ git reset --hard ORIG_HEAD

If you want to be more careful, examine reflog for HEAD, using either "git reflog" or "git log -g", and you can reset to previous version of HEAD (i.e. where current branch pointed to before 'git fetch') with

  $ git reset --hard HEAD@{1}

-- 
Jakub Narebski
Poland
ShadeHawk on #git