bpo-33608: Fix the Py_atomic_* macros.

[ericsnowcurrently]

The macros currently work because our usage happens to parse correctly. I ran into the problem while working on a PR (for bpo-33608) that involves a pointer indirection.

Note that this was part of a PR (gh-12062) that already landed and had to be reverted. This is the part that was unrelated to the need to revert.

https://bugs.python.org/issue33608

[bedevere-bot]

@ericsnowcurrently: Please replace # with GH- in the commit message next time. Thanks!

[bedevere-bot]

⚠️⚠️⚠️ Buildbot failure ⚠️⚠️⚠️

Hi! The buildbot x86 Gentoo Non-Debug with X 3.x has failed when building commit 2aab5d3.

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/99/builds/2269) and take a look at the build logs.
4. Check if the failure is related to this commit (2aab5d3) 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/99/builds/2269

Click to see traceback logs

Traceback (most recent call last):
  File "/buildbot/buildarea/cpython/3.x.ware-gentoo-x86.nondebug/build/Lib/test/test_nntplib.py", line 242, in wrapped
    meth(self)
  File "/buildbot/buildarea/cpython/3.x.ware-gentoo-x86.nondebug/build/Lib/test/test_nntplib.py", line 269, in test_with_statement
    with self.NNTP_CLASS(self.NNTP_HOST, timeout=TIMEOUT, usenetrc=False) as server:
  File "/buildbot/buildarea/cpython/3.x.ware-gentoo-x86.nondebug/build/Lib/nntplib.py", line 1077, in __init__
    self.sock = _encrypt_on(self.sock, ssl_context, host)
  File "/buildbot/buildarea/cpython/3.x.ware-gentoo-x86.nondebug/build/Lib/nntplib.py", line 292, in _encrypt_on
    return context.wrap_socket(sock, server_hostname=hostname)
  File "/buildbot/buildarea/cpython/3.x.ware-gentoo-x86.nondebug/build/Lib/ssl.py", line 405, in wrap_socket
    return self.sslsocket_class._create(
  File "/buildbot/buildarea/cpython/3.x.ware-gentoo-x86.nondebug/build/Lib/ssl.py", line 853, in _create
    self.do_handshake()
  File "/buildbot/buildarea/cpython/3.x.ware-gentoo-x86.nondebug/build/Lib/ssl.py", line 1117, in do_handshake
    self._sslobj.do_handshake()
ssl.SSLEOFError: EOF occurred in violation of protocol (_ssl.c:1055)

----------------------------------------------------------------------

Ran 106 tests in 248.592s

FAILED (errors=1, skipped=4)


Traceback (most recent call last):
  File "/buildbot/buildarea/cpython/3.x.ware-gentoo-x86.nondebug/build/Lib/test/test_nntplib.py", line 242, in wrapped
    meth(self)
  File "/buildbot/buildarea/cpython/3.x.ware-gentoo-x86.nondebug/build/Lib/test/test_nntplib.py", line 269, in test_with_statement
    with self.NNTP_CLASS(self.NNTP_HOST, timeout=TIMEOUT, usenetrc=False) as server:
  File "/buildbot/buildarea/cpython/3.x.ware-gentoo-x86.nondebug/build/Lib/nntplib.py", line 1047, in __init__
    _NNTPBase.__init__(self, file, host,
  File "/buildbot/buildarea/cpython/3.x.ware-gentoo-x86.nondebug/build/Lib/nntplib.py", line 334, in __init__
    self.getcapabilities()
  File "/buildbot/buildarea/cpython/3.x.ware-gentoo-x86.nondebug/build/Lib/nntplib.py", line 390, in getcapabilities
    resp, caps = self.capabilities()
  File "/buildbot/buildarea/cpython/3.x.ware-gentoo-x86.nondebug/build/Lib/nntplib.py", line 558, in capabilities
    resp, lines = self._longcmdstring("CAPABILITIES")
  File "/buildbot/buildarea/cpython/3.x.ware-gentoo-x86.nondebug/build/Lib/nntplib.py", line 525, in _longcmdstring
    resp, list = self._getlongresp(file)
  File "/buildbot/buildarea/cpython/3.x.ware-gentoo-x86.nondebug/build/Lib/nntplib.py", line 476, in _getlongresp
    resp = self._getresp()
  File "/buildbot/buildarea/cpython/3.x.ware-gentoo-x86.nondebug/build/Lib/nntplib.py", line 449, in _getresp
    resp = self._getline()
  File "/buildbot/buildarea/cpython/3.x.ware-gentoo-x86.nondebug/build/Lib/nntplib.py", line 437, in _getline
    if not line: raise EOFError
EOFError

----------------------------------------------------------------------

Ran 106 tests in 349.352s

FAILED (errors=1, skipped=5)

[ericsnowcurrently]

I'm pretty sure this isn't due to this commit.

[paulmon]

This ends up evaluating to _InterlockedExchange_acq((volatile long*)&((&((&_PyRuntime.ceval.gil.last_holder)->_value))->_value) causing a build error for _M_ARM