Implement PEP-600: Future 'manylinux' Platform Tags for Portable Linux Built Distributions

[mayeut]

What's the problem this feature will solve?
Allows to install packages that use a PEP600 platform tag

Describe the solution you'd like
Update packaging to 20.5 (pypa/packaging#345)

Alternative Solutions

Additional context
Given the purpose of PEP600, this should be the last - well in the foreseeable future at least - update regarding support of manylinux platform tags in pip

[uranusjr]

Is the packaging update the only thing we need to do? We can add this to 20.3 (due mid-November) if that’s the case.

[mayeut]

@uranusjr,

yes, updating packaging is the only thing required on pip end (but packaging 20.5 is not released yet, @di and @pradyunsg should have visibility on when it will be released).

I've been doing some tests around the manylinux ecosystem and updating packaging to its master branch solves this issue:

• https://github.com/mayeut/pip/tree/packaging-pep600 (pip master branch + packaging master branch)
• auditwheel manylinux_2_24 tests failing with pip 20.2.4 https://travis-ci.com/github/mayeut/auditwheel/builds/196922817
• auditwheel manylinux_2_24 tests + pip update ok with updated pip: https://travis-ci.com/github/mayeut/auditwheel/builds/196943903

[uranusjr]

Cool, I’ll add this to the 20.3 milestone as a reminder.

[h-vetinari]

Would be good to have this in, I believe? Considering the relative rarity of pip-releases, having PEP600-compatibility should IMHO be a priority.

[mayeut]

Given the comment in pypa/packaging#345 (comment), I guess this will end up in 20.3 even though the 20.3 milestone has been removed from this issue.

[pradyunsg]

Well, I thought we'd cut pip 20.3 before packaging 20.5 got ready, but Brett was faster than I was. ;)