[Wheel-builders] Wheel files for PPC64le

[Nick Coghlan]

On 12 January 2017 at 19:32, Nathaniel Smith <njs at pobox.com> wrote:
> Writing a PEP isn't too hard -- see:
>
>     https://www.python.org/dev/peps/pep-0001/
>     https://www.python.org/dev/peps/pep-0012/
>
> The standard list for discussing packaging-related PEPs is actually
> distutils-sig, not wheel-builders, so you'll want to move discussion
> over there going forward.

The ABI compatibility is the tricky part here, so this probably isn't
a bad place to talk about it until some more of the problem points are
worked out.

> The main technical issue here is that you'll want to have a somewhat
> convincing story for (a) how to build packages that will be compatible
> across a reasonable range of systems, (b) some way for pip to decide
> whether it's running on one of those systems that your packages will
> work on. I don't know enough about PPC64le to guess what this will
> look like, but you can see PEP 513 for how we did it there.

The main problem-and-opportunity for ppc64le is that it's so new that
you immediately cut down your long term support distros of interest
to:

- RHEL 7.1+
- SLES 12+
- Ubuntu 14.04+

rather than having to go all the way back to RHEL5 to establish a
relatively common ABI.

The downside is that you'd be blazing new trails in terms of finding
out just *how* common the ppc64le ABIs actually are across those
distros.

> A bonus would be if you have some nice story for how end-users can
> actually build these packages, like the manylinux docker image. But
> the manylinux docker image itself assumes the existence of
> infrastructure like Travis-CI, which is not really something that
> exists for ppc64le, I think. I guess you could try running docker in
> qemu on travis :-)

Cross-compiling from x86_64 would likely be significantly less painful
for all concerned, although you'd still need qemu to test the
resulting wheel files.

https://github.com/dockcross/dockcross looks like it may be a
potentially interesting project in that vein.

Cheers,
Nick.

-- 
Nick Coghlan   |   ncoghlan at gmail.com   |   Brisbane, Australia