Yes. Multiple ways.
You can
- just force that tree to be checked out:
git-read-tree -m v2.6.11
git-checkout-cache -f -u -a
this basically gets you the state at the time of v2.6.11, but you still
don't have a _commit_ yet, so you'd have nothing to start actual
development from. BE CAREFUL! Your "HEAD" is now pointing to something
else than what you have checked out, so the next thing you want to do
is fix that up.
- now, you can commit that as a _parentless_ commit (ie an "Initial
commit") on a new branch, with something like this:
echo "Linux 2.6.11" | git-commit-tree $(git-write-tree) > .git/refs/heads/my-branch
ln -sf .git/HEAD refs/heads/my-branch
and off you go. The above just creates a commit of the tree (which is
the v2.6.11 tree, since you did a "git-read-tree" on it), and uses the
commit message "Linux 2.6.11"). It gives it no parents, and writes the
result to the "my-branch" thing. It then makes HEAD point to that
branch, which completes the thing, and now your tree is in a consistent
state (ie HEAD matches what you have checked out, which matches
v2.6.11)
That's one way.
You can do it sneakier too, if you want to, and create the branch first. In particular, you can do
git-cat-file tag v2.6.11
which will print out that tag, which starts with:
object c39ae07f393806ccf406ef966e9a15afc43cc36a
type tree
tag v2.6.11-tree
...
and now you can just do use that tree directly, without even reading it in:
head=$(echo "Linux 2.6.11" | git-commit-tree c39ae07f393806ccf406ef966e9a15afc43cc36a)
echo $head > .git/refs/heads/my-branch
which will give you the new branch.
Now you can just do
git checkout my-branch
and you'll be there.
That said, whatever you do you will eventually end up with a series of commits that are not related to the "normal" commits in the 2.6.12-rc2+ chain, and since they don't have a common point, git won't be able to merge them for you. Git will be able to _track_ them for you, but at some point you'll want to probably try to move them forward to the "rest" of the git history.
And I'll warn you that that is not going to be entirely trivial, although Junio's "cherrypick" scripts should be useful as a way to automate it at least to some degree. This is why it would be so much easier if you could have started with a 2.6.12-rc2 or other "real" commit ;)
Linus
