[Wheel-builders] Wheel files for PPC64le

[Breno Leitao]

Hello,

> 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.

When you say ABI here, do you mean the first versions of the manylinux1
libraries, as listed in [1], that contains support (or was even compiled by
any distro) for pppc64le?

[1] https://www.python.org/dev/peps/pep-0513/#id40

If this assumption is true, we want to list the mimimum version of these
libraries that supports ABI v2 (little endian) mode?

>> 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. 

Correct.

> 
> 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.

I would say that Ubuntu 14.04 has the first initial support for ppc64le
ABI, so, it would be the base. The problem happened later, when distro
with packages other than Ubuntu 14.04 backported the ppc64le patches to these
older packages.

Anyway, there is a tool that is able to help us here:
https://www-356.ibm.com/partnerworld/wps/ospat/ospat_v1.html

>> 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 :-)

Hmm, can't we plug a remote ppc64le machine into Travis-CI? I understand
you are talking about pypa/manylinux repository, correct?

Thanks for helping us here,
Breno