On Tue, Jan 31, 2023 at 09:54:58AM +0000, brian m. carlson wrote:

I'm one of the GitHub employees who chimed in there, and I'm also a Git
contributor in my own time (and I am speaking here only in my personal
capacity, since this is a personal address).  I made a change some years
back to the archive format to fix the permissions on pax headers when
extracted as files, and kernel.org was relying on that and broke.  Linus
yelled at me because of that.

Since then, I've been very opposed to us guaranteeing output format
consistency without explicitly doing so.  I had sent some patches before
that I don't think ever got picked up that documented this explicitly.
I very much don't want people to come to rely on our behaviour unless we
explicitly guarantee it.

I understand your position, but I also think it's one of those things that
happen despite your best efforts to prevent it. :)

May I suggest adding a "git-archive --stable" that offers this guarantee,
simply as a matter of codifying the fact that the world has built
infrastructure around git's repeatable output. Maybe just for .tar (and
.tar.gz).

I know this complicates the code and makes it more "expensive" to maintain,
but it would be dramatically less expensive than changing the established
practices around the world.

-K