[llvm-dev] RFC: Dealing with out of tree changes and the LLVM git monorepo

[David Greene via llvm-dev]

Well shoot, you beat me to it.  :)

I've been working on a similar tool but it's not ready yet.  Looking
forward to trying yours!

                            -David

James Y Knight via llvm-dev <llvm-dev at lists.llvm.org> writes:

> I'm about to post exactly this tool -- I've been testing it on the
> CHERI forks of llvm/clang/lld (lots of history and merges and stuff
> there, makes a pretty nice test case!)
>
> On Mon, Nov 5, 2018 at 1:07 PM David Greene via llvm-dev
> <llvm-dev at lists.llvm.org> wrote:
>
>     Mehdi AMINI <joker.eph at gmail.com> writes:
>     
>     > Yes, but that's the case for the zipper repo anyway: one merge
>     per
>     > commit. The point is that the second commit is just a trivial
>     merge,
>     > it wouldn't show up in a file `git log` for example.
>     > In the linear rewritten monorepo, adding the history taken from
>     the
>     > existing git mirror would lead to duplicated commits, as in
>     > *identical* commit / commit with the same diff but different git
>     > hashes. I'd expect git log to show us the two commits in the git
>     log
>     > of a single file.
>     
>     Would it be valuable to have a tool to take branches from existing
>     git
>     mirrors and rewrite them in terms of the monorepo so there would
>     be no
>     duplicate commits and everything would appear to have been done
>     against
>     the monorepo?
>     
>     I know Justin is worried about hashes in old e-mails being
>     invalid, but
>     the tool could include the mapping from old hash to new hash in
>     the
>     commit message. Of course that would only be done for local
>     downstream
>     commits, as the monorepo commits were already rewritten without
>     including that information. Would it be helpful to have the
>     monorepo
>     commits contain that information?
>     
>     -David
>     _______________________________________________
>     LLVM Developers mailing list
>     llvm-dev at lists.llvm.org
>     http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev
>
> _______________________________________________
> LLVM Developers mailing list
> llvm-dev at lists.llvm.org
> http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev