FYI - LLVM migration to Git and GitHub has started

[Xin LI]

On Wed, Nov 13, 2019 at 10:29 AM Warner Losh <imp at bsdimp.com> wrote:

> Vendor branches break.
>

Speaking for this, I have took contrib/file as an opportunity to try out
how git merge works in FreeBSD's context (without using submodules).
Basically we would have the github.com/file/file histories stashed into one
branch, and perform two merges.

The first one would "bootstrap" the history, by performing a git merge with
-s ours of the previously merged tag.  This would require some cleanups:
the upstream's CVS exporter was broken and some RCS IDs were not correctly
updated, so technically one would have to patch the contrib/file tree to
bring the git's vision of RCS IDs, then perform a merge -X subtree merge.

The second one would be the actual merge (-X subtree=contrib/file).  Future
imports would only need this merge.

If the upstream was not using git, these could be pushed to a different
branch to hold it (which is pretty much what we do in subversion in its
flattened namespace under vendor/foo/dist).