Investigate/discuss setuptools build and runtime dependency versions.

[stuartarchibald]

xref: #8475 (comment), with thanks to @mbargull for raising this.

Seems like setuptools=65.6.0 has broken numpy.distutils (same way as last time #8355), the NumPy tracking issue is here numpy/numpy#22623.

NumPy folks have pinned to setuptools=59.2 numpy/numpy#22623 (comment) and are not supporting 60+ numpy/numpy#22623 (comment).

I think that #8544 removes all most all of Numba's reliance on numpy.distutils which is the part that keeps on being broken. Only the to-be-deprecated-in-0.57 pycc module has reference to numpy.distutils still.

Further xref: #8476 which needs work but makes setuptools optional at runtime.

[mbargull]

Ah, I didn't realize gh-8544 replaced numpy.distutils.misc_util.get_info('npymath') with numpy.get_include() (plus the accompanying changes). Yes, that'd probably take care of the build-time dependencies, thanks!

[stuartarchibald]

Ah, I didn't realize gh-8544 replaced numpy.distutils.misc_util.get_info('npymath') with numpy.get_include() (plus the accompanying changes). Yes, that'd probably take care of the build-time dependencies, thanks!

@mbargull No worries, raising this is really helpful, esp. the part about NumPy's policy, thanks again for that! The original intention of #8544 was to remove use of npymath.a and to fix up some ufunc loops, but having done this I realised the side effect was being able to largely drop use of numpy.distutils etc. As noted, hopefully this will prevent related future build-time issues!

[stuartarchibald]

#8544 drops numpy.distutils as noted previously, then #8476 and #8842 make setuptools optional at runtime. Closing as fixed!