bpo-42604: always set EXT_SUFFIX=${SOABI}${SHLIB_SUFFIX} when using configure

[mattip]

Continuation of bpo 39825 which was fixed for windows in gh-22088. This fix is for non-linux systems like FreeBSD and AIX. Merging gh-22088 added a test which fails on FreeBSD and AIX:

FAIL: test_EXT_SUFFIX_in_vars (test.test_sysconfig.TestSysConfig)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/usr/home/buildbot/python/3.x.koobs-freebsd-564d/build/Lib/test/test_sysconfig.py", line 368, in \
               test_EXT_SUFFIX_in_vars
    self.assertEqual(vars['EXT_SUFFIX'], _imp.extension_suffixes()[0])
AssertionError: '.so' != '.cpython-310d.so'
- .so
+ .cpython-310d.so

So EXT_SUFFIX is being set to .so rather than .cpython-310d.so. This is wrong, EXT_SUFFIX is expected to be .cpython-310d.so in this case.

The difference in EXT_SUFFIX comes from this stanza in configure and configure.ac:

case $ac_sys_system in
    Linux*|GNU*|Darwin|VxWorks)
	EXT_SUFFIX=.${SOABI}${SHLIB_SUFFIX};;
    *)
	EXT_SUFFIX=${SHLIB_SUFFIX};;
esac

where $ac_sys_system is uname -s. On FREEBSD, this is FreeBSD, and I think on AIX it is AIX. This stanza was in the original version of the files, I am not sure why the original author differentiated between the two values for EXT_SUFFIX.

https://bugs.python.org/issue42604

[bedevere-bot]

🤖 New build scheduled with the buildbot fleet by @pablogsal for commit 75e9b23 🤖

If you want to schedule another build, you need to add the ":hammer: test-with-buildbots" label again.

[miss-islington]

Thanks @mattip for the PR, and @pablogsal for merging it 🌮🎉.. I'm working now to backport this PR to: 3.8, 3.9.
🐍🍒⛏🤖

[bedevere-bot]

GH-23866 is a backport of this pull request to the 3.9 branch.

[bedevere-bot]

GH-23867 is a backport of this pull request to the 3.8 branch.

[fochoao]

The code can be made with a function with tuples or lists, instead of writing the same 5 or 6 times.

[pablogsal]

The code can be made with a function with tuples or lists, instead of writing the same 5 or 6 times.

I think you may have written in the wrong issue/PR

[fochoao]

The code can be made with a function with tuples or lists, instead of writing the same 5 or 6 times.
I think you may have written in the wrong issue/PR

Yes, it was the wrong project...