Remove `Py_TPFLAGS_HAVE_FINALIZE` macro

[rruuaanng]

Feature or enhancement

Proposal:

In https://github.com/python/cpython/blob/main/Doc/deprecations/c-api-pending-removal-in-future.rst, Many of these goals have been achieved, and this one doesn't seem to have been removed.

Has this already been discussed elsewhere?

No response given

Links to previous discussion of this feature:

No response

Linked PRs

• gh-125447: Remove Py_TPFLAGS_HAVE_FINALIZE macro #125448

[picnixz]

cc @vstinner here as well (we could however remove the usage in the project itself and its only non-test usage is in posixmodule.c, but we should not remove it from the headers)

Related: #86913 (comment)

The bit cannot be repurposed, since older extensions using the stable ABI might set it.
It doesn't make much sense to remove the Py_TPFLAGS_HAVE_VERSION_TAG or Py_TPFLAGS_HAVE_FINALIZE defines; I'd let them stay to document that the bits are reserved.

[rruuaanng]

I agree with keeping it in the header file. But I think it is necessary to remove its use in the code base.

[vstinner]

If you want to remove such constant, you should start by deprecating, and help projects to stop using it.

A code search in PyPI top 7,500 projects found that 6 projects are using it:

• Cython (3.0.9)
• Nuitka (2.1.2)
• catboost (1.2.3)
• cffi (1.16.0)
• gevent (24.2.1)
• orjson (3.9.15)

Check how these projects use the constant.

[rruuaanng]

It seems that the projects used for use are limited. I'll go to the classifier of these projects to solve these problems.

[da-woods]

Why is there any kind of urgency with this? Why not follow the normal process and announce an actual version well in advance and then wait until then?

Ultimately this is just an extra unused numeric constant that's hanging around so isn't doing any immediate harm.

Cython still supports Python 3.7 for the moment so does use the constant for that version. I'm sure we could work around the removal. But I'm not sure it's the best use of our time to have to respond to a sudden, unannounced and unnecessary removal.

[vstinner]

There is no urgency. I suggest to close this issue.