Misc/NEWS.d/3.12.0a2.rst

.. date: 2022-11-04-09-29-36
.. gh-issue: 98433
.. nonce: l76c5G
.. release date: 2022-11-14
.. section: Security

The IDNA codec decoder used on DNS hostnames by :mod:`socket` or
:mod:`asyncio` related name resolution functions no longer involves a
quadratic algorithm. This prevents a potential CPU denial of service if an
out-of-spec excessive length hostname involving bidirectional characters
were decoded. Some protocols such as :mod:`urllib` http :samp:`3{xx}` redirects
potentially allow for an attacker to supply such a name.

Individual labels within an IDNA encoded DNS name will now raise an error
early during IDNA decoding if they are longer than 1024 unicode characters
given that each decoded DNS label must be 63 or fewer characters and the
entire decoded DNS name is limited to 255. Only an application presenting a
hostname or label consisting primarily of :rfc:`3454` section 3.1 "Nothing"
characters to be removed would run into of this new limit. See also
:rfc:`5894` section 6 and :rfc:`3491`.

..

.. date: 2022-10-26-21-04-23
.. gh-issue: 98739
.. nonce: keBWcY
.. section: Security

Update bundled libexpat to 2.5.0

..

.. date: 2022-11-11-14-48-17
.. gh-issue: 81057
.. nonce: ik4iOv
.. section: Core and Builtins

The docs clearly say that :c:data:`PyImport_Inittab`,
:c:func:`PyImport_AppendInittab`, and :c:func:`PyImport_ExtendInittab`
should not be used after :c:func:`Py_Initialize` has been called. We now
enforce this for the two functions.  Additionally, the runtime now uses an
internal copy of :c:data:`PyImport_Inittab`, to guard against modification.

..

.. date: 2022-11-09-12-07-24
.. gh-issue: 99298
.. nonce: NeArAJ
.. section: Core and Builtins

Fix an issue that could potentially cause incorrect error handling for some
bytecode instructions.

..

.. date: 2022-11-08-17-47-10
.. gh-issue: 99254
.. nonce: RSvyFt
.. section: Core and Builtins

The compiler now removes all unused constants from code objects (except the
first one, which may be a docstring).

..

.. date: 2022-11-08-16-35-25
.. gh-issue: 99205
.. nonce: 2YOoFT
.. section: Core and Builtins

Fix an issue that prevented :c:type:`PyThreadState` and
:c:type:`PyInterpreterState` memory from being freed properly.

..

.. date: 2022-11-07-14-16-59
.. gh-issue: 81057
.. nonce: 3uKlLQ
.. section: Core and Builtins

The 18 global C variables holding the state of the allocators have been
moved to ``_PyRuntimeState``.  This is a strictly internal change with no
change in behavior.

..

.. date: 2022-11-07-10-29-41
.. gh-issue: 99181
.. nonce: bfG4bI
.. section: Core and Builtins

Fix failure in :keyword:`except* <except_star>` with unhashable exceptions.

..

.. date: 2022-11-07-08-17-12
.. gh-issue: 99204
.. nonce: Mf4hMD
.. section: Core and Builtins

Fix calculation of :data:`sys._base_executable` when inside a POSIX virtual
environment using copies of the python binary when the base installation
does not provide the executable name used by the venv. Calculation will fall
back to alternative names ("python<MAJOR>", "python<MAJOR>.<MINOR>").

..

.. date: 2022-11-06-22-59-02
.. gh-issue: 96055
.. nonce: TmQuJn
.. section: Core and Builtins

Update :mod:`faulthandler` to emit an error message with the proper
unexpected signal number. Patch by Donghee Na.

..

.. date: 2022-11-06-13-25-01
.. gh-issue: 99153
.. nonce: uE3CVL
.. section: Core and Builtins

Fix location of :exc:`SyntaxError` for a :keyword:`try` block with both
:keyword:`except` and :keyword:`except* <except_star>`.

..

.. date: 2022-11-06-00-47-11
.. gh-issue: 98686
.. nonce: DBDy6U
.. section: Core and Builtins

Merge the adaptive opcode logic into each instruction's unquickened variant,
and merge the logic in ``EXTENDED_ARG_QUICK`` into :opcode:`EXTENDED_ARG`.
With these changes, the quickening that happens at code object creation is
now only responsible for initializing warmup counters and inserting
superinstructions.

..

.. date: 2022-11-06-00-17-58
.. gh-issue: 99103
.. nonce: bFA9BX
.. section: Core and Builtins

Fix the error reporting positions of specialized traceback anchors when the
source line contains Unicode characters.

..

.. date: 2022-11-05-18-36-27
.. gh-issue: 99139
.. nonce: cI9vV1
.. section: Core and Builtins

Improve the error suggestion for :exc:`NameError` exceptions for instances.
Now if a :exc:`NameError` is raised in a method and the instance has an
attribute that's exactly equal to the name in the exception, the suggestion
will include ``self.<NAME>`` instead of the closest match in the method
scope. Patch by Pablo Galindo

..

.. date: 2022-11-03-13-11-17
.. gh-issue: 98401
.. nonce: CBS4nv
.. section: Core and Builtins

Octal escapes with value larger than ``0o377`` (ex: ``"\477"``), deprecated
in Python 3.11, now produce a :exc:`SyntaxWarning`, instead of
:exc:`DeprecationWarning`. In a future Python version they will be
eventually a :exc:`SyntaxError`. Patch by Victor Stinner.

..

.. date: 2022-11-02-17-02-06
.. gh-issue: 98401
.. nonce: y-dbVW
.. section: Core and Builtins

A backslash-character pair that is not a valid escape sequence now generates
a :exc:`SyntaxWarning`, instead of :exc:`DeprecationWarning`.  For example,
``re.compile("\d+\.\d+")`` now emits a :exc:`SyntaxWarning` (``"\d"`` is an
invalid escape sequence), use raw strings for regular expression:
``re.compile(r"\d+\.\d+")``. In a future Python version, :exc:`SyntaxError`
will eventually be raised, instead of :exc:`SyntaxWarning`. Patch by Victor
Stinner.

..

.. date: 2022-11-02-14-42-35
.. gh-issue: 96793
.. nonce: q0Oi74
.. section: Core and Builtins

Handle StopIteration and StopAsyncIteration raised in generator or
coroutines in the bytecode, rather than in wrapping C code.

..

.. date: 2022-10-31-22-55-34
.. gh-issue: 98931
.. nonce: AoWZ-4
.. section: Core and Builtins

Improve the :exc:`SyntaxError` error message when the user types ``import x
from y`` instead of ``from y import x``. Patch by Pablo Galindo

..

.. date: 2022-10-31-21-01-35
.. gh-issue: 98852
.. nonce: MYaRN6
.. section: Core and Builtins

Fix subscription of type aliases containing bare generic types or types like
:class:`~typing.TypeVar`: for example ``tuple[A, T][int]`` and
``tuple[TypeVar, T][int]``, where ``A`` is a generic type, and ``T`` is a
type variable.

..

.. date: 2022-10-31-18-03-10
.. gh-issue: 98925
.. nonce: zpdjVd
.. section: Core and Builtins

Lower the recursion depth for marshal on WASI to support (in-development)
wasmtime 2.0.

..

.. date: 2022-10-28-14-52-55
.. gh-issue: 98783
.. nonce: iG0kMs
.. section: Core and Builtins

Fix multiple crashes in debug mode when ``str`` subclasses are used instead
of ``str`` itself.

..

.. date: 2022-10-28-13-59-51
.. gh-issue: 98811
.. nonce: XQypJa
.. section: Core and Builtins

Use complete source locations to simplify detection of ``__future__``
imports which are not at the beginning of the file. Also corrects the offset
in the exception raised in one case, which was off by one and impeded
highlighting.

..

.. date: 2022-10-28-09-42-51
.. gh-issue: 96793
.. nonce: ucBfWO
.. section: Core and Builtins

Add specialization of :opcode:`FOR_ITER` for generators. Saves multiple
layers of dispatch and checking to get from the :opcode:`FOR_ITER`
instruction in the caller to the :opcode:`RESUME` in the generator.

..

.. date: 2022-10-27-16-42-16
.. gh-issue: 98762
.. nonce: Eb2kzg
.. section: Core and Builtins

Fix source locations of :keyword:`match` sub-patterns.

..

.. date: 2022-10-24-10-30-30
.. gh-issue: 98586
.. nonce: Tha5Iy
.. section: Core and Builtins

Added the methods :c:func:`PyObject_Vectorcall` and
:c:func:`PyObject_VectorcallMethod` to the :ref:`Limited API <stable>` along
with the auxiliary macro constant :c:macro:`PY_VECTORCALL_ARGUMENTS_OFFSET`.

The availability of these functions enables more efficient :PEP:`590` vector
calls from binary extension modules that avoid argument boxing/unboxing
overheads.

..

.. date: 2022-10-21-11-28-53
.. gh-issue: 99257
.. nonce: nmcuf-
.. section: Core and Builtins

Fix an issue where member descriptors (such as those for
:attr:`~object.__slots__`) could behave incorrectly or crash instead of
raising a :exc:`TypeError` when accessed via an instance of an invalid type.

..

.. date: 2022-10-19-23-54-43
.. gh-issue: 93143
.. nonce: 1wCYub
.. section: Core and Builtins

Rather than changing :attr:`~types.CodeType.co_code`, the interpreter will
now display a :exc:`RuntimeWarning` and assign :const:`None` to any fast
locals that are left unbound after jumps or :keyword:`del` statements
executed while tracing.

..

.. date: 2022-10-19-15-59-08
.. gh-issue: 96421
.. nonce: e22y3r
.. section: Core and Builtins

When calling into Python code from C code, through
:c:func:`PyEval_EvalFrameEx` or a related C-API function, a shim frame in
inserted into the call stack. This occurs in the
``_PyEval_EvalFrameDefault()`` function. The extra frame should be invisible
to all Python and most C extensions, but out-of-process profilers and
debuggers need to be aware of it. These shim frames can be detected by
checking ``frame->owner == FRAME_OWNED_BY_CSTACK``.

Extensions implementing their own interpreters using PEP 523 need to be
aware of this shim frame and the changes to the semantics of
:opcode:`RETURN_VALUE`, :opcode:`YIELD_VALUE`, and
:opcode:`RETURN_GENERATOR`, which now clear the frame.

..

.. date: 2022-10-19-01-01-08
.. gh-issue: 98415
.. nonce: ZS2eWh
.. section: Core and Builtins

Fix detection of MAC addresses for :mod:`uuid` on certain OSs. Patch by
Chaim Sanders

..

.. date: 2022-10-16-13-26-46
.. gh-issue: 98686
.. nonce: D9Gu_Q
.. section: Core and Builtins

Quicken all code objects, and specialize adaptive bytecode instructions more
aggressively.

..

.. date: 2022-10-15-23-15-14
.. gh-issue: 92119
.. nonce: PMSwwG
.. section: Core and Builtins

Print exception class name instead of its string representation when raising
errors from :mod:`ctypes` calls.

..

.. date: 2022-10-15-22-25-20
.. gh-issue: 91058
.. nonce: Uo2kW-
.. section: Core and Builtins

:exc:`ImportError` raised from failed ``from <module> import <name>`` now
include suggestions for the value of ``<name>`` based on the available names
in ``<module>``. Patch by Pablo Galindo

..

.. date: 2022-09-13-14-07-06
.. gh-issue: 96793
.. nonce: 7DLRSm
.. section: Core and Builtins

The :opcode:`FOR_ITER` now leaves the iterator on the stack on termination
of the loop. This is to assist specialization of loops for generators.

..

.. date: 2022-09-09-16-32-58
.. gh-issue: 90716
.. nonce: z4yuYq
.. section: Core and Builtins

Add _pylong.py module.  It includes asymptotically faster algorithms that
can be used for operations on integers with many digits.  It is used by
longobject.c to speed up some operations.

..

.. date: 2022-07-30-14-10-27
.. gh-issue: 95389
.. nonce: nSGEkG
.. section: Core and Builtins

Expose :const:`~socket.ETH_P_ALL` and some of the :ref:`ETHERTYPE_* constants
<socket-ethernet-types>` in :mod:`socket`. Patch by Noam Cohen.

..

.. date: 2022-06-10-16-37-44
.. gh-issue: 93696
.. nonce: 65BI2R
.. section: Core and Builtins

Allow :mod:`pdb` to locate source for frozen modules in the standard
library.

..

.. date: 2022-11-12-15-45-51
.. gh-issue: 99418
.. nonce: FxfAXS
.. section: Library

Fix bug in :func:`urllib.parse.urlparse` that causes URL schemes that begin
with a digit, a plus sign, or a minus sign to be parsed incorrectly.

..

.. date: 2022-11-11-18-23-41
.. gh-issue: 94597
.. nonce: m6vMDK
.. section: Library

Deprecate :class:`asyncio.AbstractChildWatcher` to be removed in Python
3.14. Patch by Kumar Aditya.

..

.. date: 2022-11-10-11-51-39
.. gh-issue: 99305
.. nonce: 6LzQc3
.. section: Library

Improve performance of :func:`secrets.token_hex`.

..

.. date: 2022-11-09-20-48-42
.. gh-issue: 74044
.. nonce: zBj26K
.. section: Library

Fixed bug where :func:`inspect.signature` reported incorrect arguments for
decorated methods.

..

.. date: 2022-11-09-12-16-35
.. gh-issue: 99275
.. nonce: klOqoL
.. section: Library

Fix ``SystemError`` in :mod:`ctypes` when exception was not set during
``__initsubclass__``.

..

.. date: 2022-11-09-08-40-52
.. gh-issue: 99277
.. nonce: J1P44O
.. section: Library

Remove older version of ``_SSLProtocolTransport.get_write_buffer_limits`` in
:mod:`!asyncio.sslproto`

..

.. date: 2022-11-08-11-15-37
.. gh-issue: 99248
.. nonce: 1vt8xI
.. section: Library

fix negative numbers failing in verify()

..

.. date: 2022-11-06-12-44-51
.. gh-issue: 99155
.. nonce: vLZOzi
.. section: Library

Fix :class:`statistics.NormalDist` pickle with ``0`` and ``1`` protocols.

..

.. date: 2022-11-05-23-16-15
.. gh-issue: 93464
.. nonce: ucd4vP
.. section: Library

``enum.auto()`` is now correctly activated when combined with other
assignment values.  E.g. ``ONE = auto(), 'some text'`` will now evaluate as
``(1, 'some text')``.

..

.. date: 2022-11-05-17-16-40
.. gh-issue: 99134
.. nonce: Msgspf
.. section: Library

Update the bundled copy of pip to version 22.3.1.

..

.. date: 2022-11-03-15-28-07
.. gh-issue: 92584
.. nonce: m5ctkm
.. section: Library

Remove the ``distutils`` package. It was deprecated in Python 3.10 by
:pep:`632` "Deprecate distutils module". For projects still using
``distutils`` and cannot be updated to something else, the ``setuptools``
project can be installed: it still provides ``distutils``. Patch by Victor
Stinner.

..

.. date: 2022-11-02-18-27-13
.. gh-issue: 98999
.. nonce: Ai2KDh
.. section: Library

Now :mod:`!_pyio` is consistent with :mod:`!_io` in raising ``ValueError``
when executing methods over closed buffers.

..

.. date: 2022-11-02-05-54-02
.. gh-issue: 83004
.. nonce: 0v8iyw
.. section: Library

Clean up refleak on failed module initialisation in :mod:`!_zoneinfo`

..

.. date: 2022-11-02-05-53-25
.. gh-issue: 83004
.. nonce: qc_KHr
.. section: Library

Clean up refleaks on failed module initialisation in :mod:`!_pickle`

..

.. date: 2022-11-02-05-52-36
.. gh-issue: 83004
.. nonce: LBl79O
.. section: Library

Clean up refleak on failed module initialisation in :mod:`!_io`.

..

.. date: 2022-10-31-12-34-03
.. gh-issue: 98897
.. nonce: rgNn4x
.. section: Library

Fix memory leak in :func:`math.dist` when both points don't have the same
dimension. Patch by Kumar Aditya.

..

.. date: 2022-10-30-22-42-48
.. gh-issue: 98878
.. nonce: fgrykp
.. section: Library

Use the frame bound builtins when offering a name suggestion in
:mod:`traceback` to prevent crashing when ``__builtins__`` is not a dict.

..

.. date: 2022-10-30-15-26-33
.. gh-issue: 98139
.. nonce: qtm-9T
.. section: Library

In :mod:`importlib._bootstrap`, enhance namespace package repr to ``<module
'x' (namespace) from ['path']>``.

..

.. date: 2022-10-29-09-42-20
.. gh-issue: 90352
.. nonce: t8QEPt
.. section: Library

Fix ``_SelectorDatagramTransport`` to inherit from
:class:`~asyncio.DatagramTransport` in :mod:`asyncio`. Patch by Kumar
Aditya.

..

.. date: 2022-10-29-03-40-18
.. gh-issue: 98793
.. nonce: WSPB4A
.. section: Library

Fix argument typechecks in :func:`!_overlapped.WSAConnect` and
:func:`!_overlapped.Overlapped.WSASendTo` functions.

..

.. date: 2022-10-28-23-44-17
.. gh-issue: 98744
.. nonce: sGHDWm
.. section: Library

Prevent crashing in :mod:`traceback` when retrieving the byte-offset for
some source files that contain certain unicode characters.

..

.. date: 2022-10-27-12-56-38
.. gh-issue: 98740
.. nonce: ZoqqGM
.. section: Library

Fix internal error in the :mod:`re` module which in very rare circumstances
prevented compilation of a regular expression containing a :ref:`conditional
expression <re-conditional-expression>` without the "else" branch.

..

.. date: 2022-10-26-07-51-55
.. gh-issue: 98703
.. nonce: 0hW773
.. section: Library

Fix :meth:`asyncio.StreamWriter.drain` to call ``protocol.connection_lost``
callback only once on Windows.

..

.. date: 2022-10-25-20-17-34
.. gh-issue: 98624
.. nonce: YQUPFy
.. section: Library

Add a mutex to unittest.mock.NonCallableMock to protect concurrent access to
mock attributes.

..

.. date: 2022-10-25-07-00-31
.. gh-issue: 98658
.. nonce: nGABW9
.. section: Library

The :class:`array.array` class now supports subscripting, making it a
:term:`generic type`.

..

.. date: 2022-10-15-10-43-45
.. gh-issue: 98284
.. nonce: SaVHTd
.. section: Library

Improved :class:`TypeError` message for undefined abstract methods of a
:class:`abc.ABC` instance. The names of the missing methods are surrounded
by single-quotes to highlight them.

..

.. date: 2022-10-10-07-07-31
.. gh-issue: 96151
.. nonce: K9fwoq
.. section: Library

Allow ``BUILTINS`` to be a valid field name for frozen dataclasses.

..

.. date: 2022-10-08-19-39-27
.. gh-issue: 98086
.. nonce: y---WC
.. section: Library

Make sure ``patch.dict()`` can be applied on async functions.

..

.. date: 2022-09-05-17-08-56
.. gh-issue: 72719
.. nonce: jUpzF3
.. section: Library

Remove modules :mod:`!asyncore` and :mod:`!asynchat`, which were deprecated by
:pep:`594`.

..

.. date: 2022-08-23-03-13-18
.. gh-issue: 96192
.. nonce: TJywOF
.. section: Library

Fix handling of ``bytes`` :term:`path-like objects <path-like object>` in
:func:`os.ismount`.

..

.. date: 2022-06-23-15-36-49
.. gh-issue: 94172
.. nonce: DzQk0s
.. section: Library

:mod:`ftplib`: Remove the ``FTP_TLS.ssl_version`` class attribute: use the
*context* parameter instead. Patch by Victor Stinner

..

.. date: 2022-06-23-15-31-49
.. gh-issue: 94172
.. nonce: AXE2IZ
.. section: Library

Remove the *keyfile* and *certfile* parameters from the
:mod:`ftplib`, :mod:`imaplib`, :mod:`poplib` and :mod:`smtplib` modules,
and the *key_file*, *cert_file* and *check_hostname* parameters from the
:mod:`http.client` module,
all deprecated since Python 3.6. Use the *context*
parameter (*ssl_context* in :mod:`imaplib`) instead. Patch by Victor
Stinner.

..

.. date: 2022-06-14-22-46-05
.. gh-issue: 83638
.. nonce: 73xfGK
.. section: Library

Add the :attr:`~sqlite3.Connection.autocommit` attribute to
:class:`sqlite3.Connection` and the *autocommit* parameter to
:func:`sqlite3.connect` to control :pep:`249`-compliant :ref:`transaction
handling <sqlite3-transaction-control-autocommit>`. Patch by Erlend E.
Aasland.

..

.. date: 2022-05-08-08-47-32
.. gh-issue: 92452
.. nonce: 3pNHe6
.. section: Library

Fixed a race condition that could cause :func:`sysconfig.get_config_var` to
incorrectly return :const:`None` in multi-threaded programs.

..

.. date: 2022-05-03-11-32-29
.. gh-issue: 91803
.. nonce: pI4Juv
.. section: Library

Fix an error when using a method of objects mocked with
:func:`unittest.mock.create_autospec` after it was sealed with
:func:`unittest.mock.seal` function.

..

.. bpo: 38523
.. date: 2020-10-23-22-20-52
.. nonce: CrkxLh
.. section: Library

:func:`shutil.copytree` now applies the *ignore_dangling_symlinks* argument
recursively.

..

.. bpo: 40358
.. date: 2020-04-30-02-15-08
.. nonce: A4ygqe
.. section: Library

Add walk_up argument in :meth:`pathlib.PurePath.relative_to`.

..

.. bpo: 36267
.. date: 2019-09-03-15-45-19
.. nonce: z42Ex7
.. section: Library

Fix IndexError in :class:`argparse.ArgumentParser` when a ``store_true``
action is given an explicit argument.

..

.. date: 2022-10-29-02-33-46
.. gh-issue: 98832
.. nonce: DudEIH
.. section: Documentation

Changes wording of docstring for :func:`pathlib.Path.iterdir`.

..

.. date: 2022-10-06-13-00-28
.. gh-issue: 97966
.. nonce: fz7kFg
.. section: Documentation

Update uname docs to clarify the special nature of the platform attribute
and to indicate when it became late-bound.

..

.. date: 2022-10-31-14-47-49
.. gh-issue: 98903
.. nonce: 7KinCV
.. section: Tests

The Python test suite now fails with exit code 4 if no tests ran. It should
help detecting typos in test names and test methods.

..

.. date: 2022-10-26-15-19-20
.. gh-issue: 98713
.. nonce: Lnu32R
.. section: Tests

Fix a bug in the :mod:`typing` tests where a test relying on
CPython-specific implementation details was not decorated with
``@cpython_only`` and was not skipped on other implementations.

..

.. date: 2022-10-15-07-46-48
.. gh-issue: 87390
.. nonce: asR-Zo
.. section: Tests

Add tests for star-unpacking with PEP 646, and some other miscellaneous PEP
646 tests.

..

.. date: 2022-10-12-14-57-06
.. gh-issue: 96853
.. nonce: ANe-bw
.. section: Tests

Added explicit coverage of ``Py_Initialize`` (and hence ``Py_InitializeEx``)
back to the embedding tests (all other embedding tests migrated to
``Py_InitializeFromConfig`` in Python 3.11)

..

.. bpo: 34272
.. date: 2018-07-29-15-59-51
.. nonce: lVX2uR
.. section: Tests

Some C API tests were moved into the new Lib/test/test_capi/ directory.

..

.. date: 2022-11-04-02-58-10
.. gh-issue: 99086
.. nonce: DV_4Br
.. section: Build

Fix ``-Wimplicit-int`` compiler warning in :program:`configure` check for
``PTHREAD_SCOPE_SYSTEM``.

..

.. date: 2022-11-02-19-25-07
.. gh-issue: 99016
.. nonce: R05NkD
.. section: Build

Fix build with ``PYTHON_FOR_REGEN=python3.8``.

..

.. date: 2022-11-02-18-45-35
.. gh-issue: 97731
.. nonce: zKpTlj
.. section: Build

Specify the full path to the source location for ``make docclean`` (needed
for cross-builds).

..

.. date: 2022-11-02-10-56-40
.. gh-issue: 98949
.. nonce: 3SRD8C
.. section: Build

Drop unused build dependency on ``readelf``.

..

.. date: 2022-11-01-21-45-58
.. gh-issue: 98989
.. nonce: tMxbdB
.. section: Build

Use ``python3.11``, if available, for regeneration and freezing.

..

.. date: 2022-10-28-22-24-26
.. gh-issue: 98831
.. nonce: IXRCRX
.. section: Build

Add new tooling, in ``Tools/cases_generator``, to generate the interpreter
switch statement from a list of opcode definitions. This only affects
adding, modifying or removing instruction definitions. The instruction
definitions now live in ``Python/bytecodes.c``, in the form of a `custom DSL
(under development)
<https://github.com/faster-cpython/ideas/blob/main/3.12/interpreter_definition.md>`__.
The tooling reads this file and writes ``Python/generated_cases.c.h``, which
is then included by ``Python/ceval.c`` to provide most of the cases of the
main interpreter switch.

..

.. date: 2022-10-28-18-53-40
.. gh-issue: 98817
.. nonce: oPqrtt
.. section: Build

Remove PCbuild/lib.pyproj: it's not used for anything, is only a minor
convenience for Visual Studio users (who probably mostly don't even know
about it), and it takes a lot of maintenance effort to keep updated.

..

.. date: 2022-10-27-19-47-31
.. gh-issue: 98776
.. nonce: lt_UOG
.. section: Build

Fix ``make regen-test-levenshtein`` for out-of-tree builds.

..

.. date: 2022-10-26-12-37-52
.. gh-issue: 98707
.. nonce: eVXGEx
.. section: Build

Don't use vendored ``libmpdec`` headers if :option:`--with-system-libmpdec`
is passed to :program:`configure`. Don't use vendored ``libexpat`` headers
if :option:`--with-system-expat` is passed to :program:`configure`.

..

.. date: 2022-11-01-11-07-33
.. gh-issue: 98689
.. nonce: 0f6e_N
.. section: Windows

Update Windows builds to zlib v1.2.13.  v1.2.12 has :cve:`2022-37434`, but the
vulnerable ``inflateGetHeader`` API is not used by Python.

..

.. date: 2022-11-01-00-37-13
.. gh-issue: 98790
.. nonce: fpaPAx
.. section: Windows

Assumes that a missing ``DLLs`` directory means that standard extension
modules are in the executable's directory.

..

.. date: 2022-10-27-20-30-16
.. gh-issue: 98745
.. nonce: v06p4r
.. section: Windows

Update :file:`py.exe` launcher to install 3.11 by default and 3.12 on
request.

..

.. date: 2022-10-26-17-43-09
.. gh-issue: 98692
.. nonce: bOopfZ
.. section: Windows

Fix the :ref:`launcher` ignoring unrecognized shebang lines instead of
treating them as local paths

..

.. date: 2022-10-25-10-34-17
.. gh-issue: 94328
.. nonce: 19NhdU
.. section: Windows

Update Windows installer to use SQLite 3.39.4.

..

.. date: 2022-10-25-10-32-23
.. gh-issue: 94328
.. nonce: W3YNC_
.. section: macOS

Update macOS installer to SQLite 3.39.4.

..

.. date: 2022-11-04-16-13-35
.. gh-issue: 98724
.. nonce: p0urWO
.. section: C API

The :c:macro:`Py_CLEAR`, :c:macro:`Py_SETREF` and :c:macro:`Py_XSETREF`
macros now only evaluate their argument once. If the argument has side
effects, these side effects are no longer duplicated. Patch by Victor
Stinner.

..

.. date: 2022-11-03-17-46-41
.. gh-issue: 98978
.. nonce: KJjBvv
.. section: C API

Fix use-after-free in ``Py_SetPythonHome(NULL)``,
``Py_SetProgramName(NULL)`` and ``_Py_SetProgramFullPath(NULL)`` function
calls. Issue reported by Benedikt Reinartz. Patch by Victor Stinner.

..

.. date: 2022-10-25-17-50-43
.. gh-issue: 98410
.. nonce: NSXYfm
.. section: C API

Add ``getbufferproc`` and ``releasebufferproc`` to the stable API.

..

.. date: 2022-10-24-12-09-17
.. gh-issue: 98610
.. nonce: PLX2Np
.. section: C API

Some configurable capabilities of sub-interpreters have changed. They always
allow subprocesses (:mod:`subprocess`) now, whereas before subprocesses
could be optionally disallowed for a sub-interpreter. Instead
:func:`os.exec` can now be disallowed. Disallowing daemon threads is now
supported.  Disallowing all threads is still allowed, but is never done by
default. Note that the optional restrictions are only available through
``_Py_NewInterpreterFromConfig()``, which isn't a public API. They do not
affect the main interpreter, nor :c:func:`Py_NewInterpreter`.

..

.. date: 2022-10-24-11-26-55
.. gh-issue: 98608
.. nonce: _Q2lNV
.. section: C API

A ``_PyInterpreterConfig`` has been added and ``_Py_NewInterpreter()`` has
been renamed to ``_Py_NewInterpreterFromConfig()``.  The
"isolated_subinterpreters" argument is now a granular config that captures
the previous behavior.  Note that this is all "private" API.

..

.. date: 2022-10-16-15-00-25
.. gh-issue: 96853
.. nonce: V0wiXP
.. section: C API

``Py_InitializeEx`` now correctly calls ``PyConfig_Clear`` after
initializing the interpreter (the omission didn't cause a memory leak only
because none of the dynamically allocated config fields are populated by the
wrapper function)

..

.. date: 2022-08-05-15-26-12
.. gh-issue: 91248
.. nonce: ujirJJ
.. section: C API

Add :c:func:`PyFrame_GetVar` and :c:func:`PyFrame_GetVarString` functions to
get a frame variable by its name. Patch by Victor Stinner.