[3.12] gh-102304: Fix Py_INCREF() for limited C API 3.9

[vstinner]

• Issue: Move _Py_RefTotal to PyInterpreterState #102304

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📚 Documentation preview 📚: https://cpython-previews--105553.org.readthedocs.build/

[bedevere-bot]

⚠️⚠️⚠️ Buildbot failure ⚠️⚠️⚠️

Hi! The buildbot AMD64 Arch Linux TraceRefs 3.12 has failed when building commit d29e86b.

What do you need to do:

1. Don't panic.
2. Check the buildbot page in the devguide if you don't know what the buildbots are or how they work.
3. Go to the page of the buildbot that failed (https://buildbot.python.org/all/#builders/1197/builds/58) and take a look at the build logs.
4. Check if the failure is related to this commit (d29e86b) or if it is a false positive.
5. If the failure is related to this commit, please, reflect that on the issue and make a new Pull Request with a fix.

You can take a look at the buildbot page here:

https://buildbot.python.org/all/#builders/1197/builds/58

Failed tests:

• test__xxsubinterpreters
• test__xxinterpchannels

Summary of the results of the build (if available):

==

Click to see traceback logs

remote: Enumerating objects: 7, done.        
remote: Counting objects:  14% (1/7)        
remote: Counting objects:  28% (2/7)        
remote: Counting objects:  42% (3/7)        
remote: Counting objects:  57% (4/7)        
remote: Counting objects:  71% (5/7)        
remote: Counting objects:  85% (6/7)        
remote: Counting objects: 100% (7/7)        
remote: Counting objects: 100% (7/7), done.        
remote: Compressing objects:  50% (1/2)        
remote: Compressing objects: 100% (2/2)        
remote: Compressing objects: 100% (2/2), done.        
remote: Total 7 (delta 5), reused 6 (delta 5), pack-reused 0        
From https://github.com/python/cpython
 * branch                  3.12       -> FETCH_HEAD
Note: switching to 'd29e86bea3bcd7a8379d8368b36c718ab7b5b3f3'.

You are in 'detached HEAD' state. You can look around, make experimental
changes and commit them, and you can discard any commits you make in this
state without impacting any branches by switching back to a branch.

If you want to create a new branch to retain commits you create, you may
do so (now or later) by using -c with the switch command. Example:

  git switch -c <new-branch-name>

Or undo this operation with:

  git switch -

Turn off this advice by setting config variable advice.detachedHead to false

HEAD is now at d29e86bea3 [3.12] gh-102304: Fix Py_INCREF() for limited C API 3.9 (#105553)
Switched to and reset branch '3.12'

Objects/object.c:2211: _Py_ForgetReference: Assertion failed: invalid object chain
Enable tracemalloc to get the memory block allocation traceback

object address  : 0x7f6bf962d300
object refcount : 0
object type     : 0x55a320cd18c0
object type name: bytes
object repr     : <refcnt 0 at 0x7f6bf962d300>

Fatal Python error: _PyObject_AssertFailed: _PyObject_AssertFailed
Python runtime state: initialized

Current thread 0x00007f6c09e2e740 (most recent call first):
  <no Python frame>
Debug memory block at address p=0x7f6c09d55e90: API '�'
    18302063728033398269 bytes originally requested
    The 7 pad bytes at p-7 are not all FORBIDDENBYTE (0xfd):
        at p-7: 0xdd *** OUCH
        at p-6: 0xdd *** OUCH
        at p-5: 0xdd *** OUCH
        at p-4: 0xdd *** OUCH
        at p-3: 0xdd *** OUCH
        at p-2: 0xdd *** OUCH
        at p-1: 0xdd *** OUCH
    Because memory is corrupted at the start, the count of bytes requested
       may be bogus, and checking the trailing pad bytes may segfault.
    The 8 pad bytes at tail=0xfdfe7d6a07d35c8d are Fatal Python error: Segmentation fault

Current thread 0x00007f6c09e2e740 (most recent call first):
  <no Python frame>

Extension modules: _testcapi, _xxsubinterpreters, _xxinterpchannels (total: 3)
make: *** [Makefile:2015: buildbottest] Segmentation fault (core dumped)

Cannot open file '/buildbot/buildarea/3.12.pablogsal-arch-x86_64/build/test-results.xml' for upload