Generate wheel for Cython 3.0.8

[lesteve]

In scikit-learn we are testing nogil and we recently updated our minimum supported Cython version to 3.0.8 in scikit-learn/scikit-learn#28284.

Let's be optimist and update this action to see whether that works 🤞!

[lesteve]

@colesbury so this action is trigger manually (workflow_dispatch), I am not sure whether there is a way to test it in this PR ...

More generally I am wondering if other people have showed interest for Cython 3 in nogil. There may be some known issues that I am not aware of.

[lesteve]

@colesbury I have a modified version of Cython 3.0.8 that compiles. This modified Cython version can compile scikit-learn and the scikit-learn tests pass with nogil-3.9.

The diff compared to Cython 3.0.8 is quite small, since I guess some work has been upstreamed into Cython:
https://github.com/cython/cython/compare/3.0.x...lesteve:cython:3.0.8-nogil?expand=1

• I cherry-picked two of your commits that still made sense on your 0.29.29-nogil tag and they moved some of the code to the right elif clause.
• CYTHON_METH_FASTCALL needs to be disabled for Cython to compile.
• I was not sure about CYTHON_PEP489_MULTI_PHASE_INIT so I kept the code as in your Cython fork

I am not sure what still needs to be done to turn it into a Cython 3 wheel in https://d1yxz45j0ypngg.cloudfront.net/cython/.

Of course, I completely understand if you have plenty of higher priority things to do!

If there is anything that I can help with, let me know!

[colesbury]

Thanks @lesteve. I added the CYTHON_METH_FASTCALL change to https://github.com/colesbury/cython/tree/3.0.8-nogil and a 3.0.x build file https://github.com/colesbury/nogil-wheels/blob/main/.github/workflows/cython-3.0.yml.

I started the wheel builds, but it looks like it will take the GitHub runners a little while to pick them up.

[lesteve]

Looks like there are genuine issues in the Github Action, maybe this is fixed in cibuildwheel 2.16.5 as this seems similar to pypa/cibuildwheel#1740.

Error:

Run pipx run --python "C:\hostedtoolcache\windows\Python\3.11.8\x64\python.exe" --spec "D:\a\_actions\colesbury\cibuildwheel\nogil" cibuildwheel "." --output-dir '"wheelhouse"' --config-file '""' --only '""'
  pipx run --python "C:\hostedtoolcache\windows\Python\3.11.8\x64\python.exe" --spec "D:\a\_actions\colesbury\cibuildwheel\nogil" cibuildwheel "." --output-dir '"wheelhouse"' --config-file '""' --only '""'
  shell: C:\Program Files\PowerShell\7\pwsh.EXE -command ". '{0}'"
  env:
    VERSION: 3.0.8
    CIBW_BUILD: nogil39-*
    CIBW_ARCHS_LINUX: auto
    CIBW_ARCHS_MACOS: universal2
    CIBW_ARCHS_WINDOWS: AMD64
    CIBW_ENVIRONMENT: CFLAGS='-O3 -g0 -mtune=generic -pipe -fPIC' LDFLAGS='-fPIC'
Invalid --only='""', must be a build selector with a known platform
creating virtual environment...
creating virtual environment...
determining package name from 'D:\\a\\_actions\\colesbury\\cibuildwheel\\nogil'...
installing cibuildwheel from spec 'D:\\a\\_actions\\colesbury\\cibuildwheel\\nogil'...
Error: Process completed with exit code 1.

[colesbury]

Ah, thanks for the pointer!

[colesbury]

Ok, the Cython 3.0.8 wheel is uploaded. Please let me know if it works okay.

[lesteve]

Great, thanks!

Seems like the scikit-learn nogil build is happy in scikit-learn/scikit-learn#28338 so I am happy too, let's close this one!