bpo-32096: Statically initialize the default raw allocator.

[ericsnowcurrently]

The recent global runtime state consolidation broke pre-init usage of Py_DecodeLocale(). This patch fixes that.

https://bugs.python.org/issue32096

[ncoghlan]

In addition to a NEWS entry, it would be preferable to add an explicit test for this to _testembed.c.

[ncoghlan]

Doubled word "before before" in the comment.

[ericsnowcurrently]

fixed

[bedevere-bot]

A Python core developer has requested some changes be made to your pull request before we can consider merging it. If you could please address their requests along with any other requests in other reviews from core developers that would be appreciated.

Once you have made the requested changes, please leave a comment on this pull request containing the phrase I have made the requested changes; please review again. I will then notify any core developers who have left a review that you're ready for them to take another look at this pull request.

[ncoghlan]

For the explicit test, I'd suggest a dedicated one that just does:

ptr = Py_DecodeLocale();
Py_Initialize();
Py_Finalize();
PyMem_RawFree(ptr);

We can then consider adding equivalent tests for other "safe before Py_Initialize" APIs in https://bugs.python.org/issue32086

[ncoghlan]

This looks good to me, but I'm not entirely sure I understand the NEWS entry.

Unless the NEWS entry has typos in it, in which case it makes sense and just needs the typos fixed :)

[ncoghlan]

Should the last two names here have underscore prefixes?

[ncoghlan]

CI failure looks real though - my guess would be an allocator/deallocator mismatch due to Py_Finalize not explicitly reverting back to the default allocator.

[ericsnowcurrently]

This PR has been superseded by PR #4532, which reverts the mem-related globals consolidation. We will revisit a long-term solution later.