.. date: 2025-09-14-13-35-44
.. gh-issue: 128067
.. nonce: BGdP_A
.. release date: 2026-02-03
.. section: Windows

Fix a bug in PyREPL on Windows where output without a trailing newline was
overwritten by the next prompt.

..

.. date: 2026-01-02-11-44-56
.. gh-issue: 142095
.. nonce: 4ssgnM
.. section: Tools/Demos

Make gdb 'py-bt' command use frame from thread local state when available.
Patch by Sam Gross and Victor Stinner.

..

.. date: 2026-02-03-07-57-24
.. gh-issue: 144415
.. nonce: U3L15r
.. section: Tests

The Android testbed now distinguishes between stdout/stderr messages which
were triggered by a newline, and those triggered by a manual call to
``flush``. This fixes logging of progress indicators and similar content.

..

.. date: 2026-01-09-13-52-10
.. gh-issue: 143460
.. nonce: _nW2jt
.. section: Tests

Skip tests relying on infinite recusion if stack size is unlimited.

..

.. date: 2026-01-08-16-56-59
.. gh-issue: 65784
.. nonce: aKNo1U
.. section: Tests

Add support for parametrized resource ``wantobjects`` in regrtests, which
allows to run Tkinter tests with the specified value of
:data:`!tkinter.wantobjects`, for example ``-u wantobjects=0``.

..

.. date: 2026-01-08-11-50-06
.. gh-issue: 143553
.. nonce: KyyNTt
.. section: Tests

Add support for parametrized resources, such as ``-u xpickle=2.7``.

..

.. date: 2025-12-17-02-02-57
.. gh-issue: 142836
.. nonce: mR-fvK
.. section: Tests

Accommodated Solaris in ``test_pdb.test_script_target_anonymous_pipe``.

..

.. bpo: 31391
.. date: 2020-09-29-23-14-01
.. nonce: IZr2P8
.. section: Tests

Forward-port test_xpickle from Python 2 to Python 3 and add the resource
back to test's command line.

..

.. date: 2026-01-21-12-34-05
.. gh-issue: 144125
.. nonce: TAz5uo
.. section: Security

:mod:`~email.generator.BytesGenerator` will now refuse to serialize (write)
headers that are unsafely folded or delimited; see
:attr:`~email.policy.Policy.verify_generated_headers`. (Contributed by Bas
Bloemsaat and Petr Viktorin in :gh:`121650`).

..

.. date: 2026-01-16-14-40-31
.. gh-issue: 143935
.. nonce: U2YtKl
.. section: Security

Fixed a bug in the folding of comments when flattening an email message
using a modern email policy. Comments consisting of a very long sequence of
non-foldable characters could trigger a forced line wrap that omitted the
required leading space on the continuation line, causing the remainder of
the comment to be interpreted as a new header field. This enabled header
injection with carefully crafted inputs.

..

.. date: 2026-01-16-11-51-19
.. gh-issue: 143925
.. nonce: mrtcHW
.. section: Security

Reject control characters in ``data:`` URL media types.

..

.. date: 2026-01-16-11-13-15
.. gh-issue: 143919
.. nonce: kchwZV
.. section: Security

Reject control characters in :class:`http.cookies.Morsel` fields and values.

..

.. date: 2026-01-16-11-07-36
.. gh-issue: 143916
.. nonce: dpWeOD
.. section: Security

Reject C0 control characters within wsgiref.headers.Headers fields, values,
and parameters.

..

.. date: 2026-02-01-15-25-00
.. gh-issue: 144380
.. nonce: U7py_s
.. section: Library

Improve performance of :class:`io.BufferedReader` line iteration by ~49%.

..

.. date: 2026-01-23-06-43-21
.. gh-issue: 144169
.. nonce: LFy9yi
.. section: Library

Fix three crashes when non-string keyword arguments are supplied to objects
in the :mod:`ast` module.

..

.. date: 2026-01-21-19-39-07
.. gh-issue: 144100
.. nonce: hLMZ8Y
.. section: Library

Fixed a crash in ctypes when using a deprecated ``POINTER(str)`` type in
``argtypes``. Instead of aborting, ctypes now raises a proper Python
exception when the pointer target type is unresolved.

..

.. date: 2026-01-20-16-35-55
.. gh-issue: 144050
.. nonce: 0kKFbF
.. section: Library

Fix :func:`stat.filemode` in the pure-Python implementation to avoid
misclassifying invalid mode values as block devices.

..

.. date: 2026-01-19-00-57-40
.. gh-issue: 144023
.. nonce: 29XUcp
.. section: Library

Fixed validation of file descriptor 0 in posix functions when used with
follow_symlinks parameter.

..

.. date: 2026-01-18-14-35-37
.. gh-issue: 143999
.. nonce: MneN4O
.. section: Library

Fix an issue where :func:`inspect.getgeneratorstate` and
:func:`inspect.getcoroutinestate` could fail for generators wrapped by
:func:`types.coroutine` in the suspended state.

..

.. date: 2026-01-16-06-22-10
.. gh-issue: 143831
.. nonce: VLBTLp
.. section: Library

:class:`annotationlib.ForwardRef` objects are now hashable when created from
annotation scopes with closures. Previously, hashing such objects would
throw an exception. Patch by Bartosz Sławecki.

..

.. date: 2026-01-15-16-04-39
.. gh-issue: 143874
.. nonce: 1qQgvo
.. section: Library

Fixed a bug in :mod:`pdb` where expression results were not sent back to
remote client.

..

.. date: 2026-01-15-13-03-22
.. gh-issue: 143880
.. nonce: sWoLsf
.. section: Library

Fix data race in :func:`functools.partial` in the :term:`free threading`
build.

..

.. date: 2026-01-12-07-17-38
.. gh-issue: 143706
.. nonce: sysArgv
.. section: Library

Fix :mod:`multiprocessing` forkserver so that :data:`sys.argv` is correctly
set before ``__main__`` is preloaded. Previously, :data:`sys.argv` was empty
during main module import in forkserver child processes. This fixes a
regression introduced in 3.13.8 and 3.14.1. Root caused by Aaron Wieczorek,
test provided by Thomas Watson, thanks!

..

.. date: 2026-01-10-16-42-47
.. gh-issue: 143638
.. nonce: du5G7d
.. section: Library

Forbid reentrant calls of the :class:`pickle.Pickler` and
:class:`pickle.Unpickler` methods for the C implementation. Previously, this
could cause crash or data corruption, now concurrent calls of methods of the
same object raise :exc:`RuntimeError`.

..

.. date: 2026-01-10-10-04-08
.. gh-issue: 78724
.. nonce: xkXfxX
.. section: Library

Raise :exc:`RuntimeError`'s when user attempts to call methods on
half-initialized :class:`~struct.Struct` objects, For example, created by
``Struct.__new__(Struct)``.  Patch by Sergey B Kirpichev.

..

.. date: 2026-01-09-17-50-26
.. gh-issue: 143196
.. nonce: WxKxzU
.. section: Library

Fix crash when the internal encoder object returned by undocumented function
:func:`!json.encoder.c_make_encoder` was called with non-zero second
(*_current_indent_level*) argument.

..

.. date: 2026-01-09-13-07-22
.. gh-issue: 143191
.. nonce: PPR_vW
.. section: Library

:func:`_thread.stack_size` now raises :exc:`ValueError` if the stack size is
too small. Patch by Victor Stinner.

..

.. date: 2026-01-09-12-37-19
.. gh-issue: 143602
.. nonce: V8vQpj
.. section: Library

Fix a inconsistency issue in :meth:`~io.RawIOBase.write` that leads to
unexpected buffer overwrite by deduplicating the buffer exports.

..

.. date: 2026-01-08-14-53-46
.. gh-issue: 143547
.. nonce: wHBVlr
.. section: Library

Fix :func:`sys.unraisablehook` when the hook raises an exception and changes
:func:`sys.unraisablehook`: hold a strong reference to the old hook. Patch
by Victor Stinner.

..

.. date: 2026-01-07-15-49-06
.. gh-issue: 143517
.. nonce: FP5KgL
.. section: Library

:func:`annotationlib.get_annotations` no longer raises a :exc:`SyntaxError`
when evaluating a stringified starred annotation that starts with one or
more whitespace characters followed by a ``*``. Patch by Bartosz Sławecki.

..

.. date: 2026-01-03-19-41-36
.. gh-issue: 143378
.. nonce: 29AvE7
.. section: Library

Fix use-after-free crashes when a :class:`~io.BytesIO` object is
concurrently mutated during :meth:`~io.RawIOBase.write` or
:meth:`~io.IOBase.writelines`.

..

.. date: 2026-01-02-12-55-52
.. gh-issue: 143346
.. nonce: iTekce
.. section: Library

Fix incorrect wrapping of the Base64 data in :class:`!plistlib._PlistWriter`
when the indent contains a mix of tabs and spaces.

..

.. date: 2026-01-01-11-21-57
.. gh-issue: 143310
.. nonce: 8rxtH3
.. section: Library

:mod:`tkinter`: fix a crash when a Python :class:`list` is mutated during
the conversion to a Tcl object (e.g., when setting a Tcl variable). Patch by
Bénédikt Tran.

..

.. date: 2025-12-31-20-43-02
.. gh-issue: 143309
.. nonce: cdFxdH
.. section: Library

Fix a crash in :func:`os.execve` on non-Windows platforms when given a
custom environment mapping which is then mutated during parsing. Patch by
Bénédikt Tran.

..

.. date: 2025-12-31-17-38-33
.. gh-issue: 143308
.. nonce: lY8UCR
.. section: Library

:mod:`pickle`: fix use-after-free crashes when a
:class:`~pickle.PickleBuffer` is concurrently mutated by a custom buffer
callback during pickling. Patch by Bénédikt Tran and Aaron Wieczorek.

..

.. date: 2025-12-28-20-28-05
.. gh-issue: 143237
.. nonce: q1ymuA
.. section: Library

Fix support of named pipes in the rotating :mod:`logging` handlers.

..

.. date: 2025-12-28-14-41-02
.. gh-issue: 143249
.. nonce: K4vEp4
.. section: Library

Fix possible buffer leaks in Windows overlapped I/O on error handling.

..

.. date: 2025-12-28-13-49-06
.. gh-issue: 143241
.. nonce: 5H4b8d
.. section: Library

:mod:`zoneinfo`: fix infinite loop in :meth:`ZoneInfo.from_file
<zoneinfo.ZoneInfo.from_file>` when parsing a malformed TZif file. Patch by
Fatih Celik.

..

.. date: 2025-12-28-13-12-40
.. gh-issue: 142830
.. nonce: uEyd6r
.. section: Library

:mod:`sqlite3`: fix use-after-free crashes when the connection's callbacks
are mutated during a callback execution. Patch by Bénédikt Tran.

..

.. date: 2025-12-27-15-41-27
.. gh-issue: 143200
.. nonce: 2hEUAl
.. section: Library

:mod:`xml.etree.ElementTree`: fix use-after-free crashes in
:meth:`~object.__getitem__` and :meth:`~object.__setitem__` methods of
:class:`~xml.etree.ElementTree.Element` when the element is concurrently
mutated. Patch by Bénédikt Tran.

..

.. date: 2025-12-27-00-14-56
.. gh-issue: 142195
.. nonce: UgBEo5
.. section: Library

Updated timeout evaluation logic in :mod:`subprocess` to be compatible with
deterministic environments like Shadow where time moves exactly as
requested.

..

.. date: 2025-12-25-08-58-55
.. gh-issue: 142164
.. nonce: XrFztf
.. section: Library

Fix the ctypes bitfield overflow error message to report the correct offset
and size calculation.

..

.. date: 2025-12-24-14-18-52
.. gh-issue: 143145
.. nonce: eXLw8D
.. section: Library

Fixed a possible reference leak in ctypes when constructing results with
multiple output parameters on error.

..

.. date: 2025-12-22-22-36-21
.. gh-issue: 122431
.. nonce: 9E3085
.. section: Library

Corrected the error message in :func:`readline.append_history_file` to state
that ``nelements`` must be non-negative instead of positive.

..

.. date: 2025-12-22-00-00-00
.. gh-issue: 143004
.. nonce: uaf-counter
.. section: Library

Fix a potential use-after-free in :meth:`collections.Counter.update` when
user code mutates the Counter during an update.

..

.. date: 2025-12-21-17-44-28
.. gh-issue: 143046
.. nonce: GBa5Ip
.. section: Library

The :mod:`asyncio` REPL no longer prints copyright and version messages in
the quiet mode (:option:`-q`). Patch by Bartosz Sławecki.

..

.. date: 2025-12-21-17-24-29
.. gh-issue: 140648
.. nonce: i8dca6
.. section: Library

The :mod:`asyncio` REPL now respects the :option:`-I` flag (isolated mode).
Previously, it would load and execute :envvar:`PYTHONSTARTUP` even if the
flag was set. Contributed by Bartosz Sławecki.

..

.. date: 2025-12-20-10-21-23
.. gh-issue: 142991
.. nonce: jYHD9E
.. section: Library

Fixed socket operations such as recvfrom() and sendto() for FreeBSD
divert(4) socket.

..

.. date: 2025-12-20-01-49-02
.. gh-issue: 143010
.. nonce: _-SWX0
.. section: Library

Fixed a bug in :mod:`mailbox` where the precise timing of an external event
could result in the library opening an existing file instead of a file it
expected to create.

..

.. date: 2025-12-17-20-18-17
.. gh-issue: 142881
.. nonce: 5IizIQ
.. section: Library

Fix concurrent and reentrant call of :func:`atexit.unregister`.

..

.. date: 2025-12-17-14-41-09
.. gh-issue: 112127
.. nonce: 13OHQk
.. section: Library

Fix possible use-after-free in :func:`atexit.unregister` when the callback
is unregistered during comparison.

..

.. date: 2025-12-16-14-49-19
.. gh-issue: 142783
.. nonce: VPV1ig
.. section: Library

Fix zoneinfo use-after-free with descriptor _weak_cache. a descriptor as
_weak_cache could cause crashes during object creation. The fix ensures
proper reference counting for descriptor-provided objects.

..

.. date: 2025-12-16-11-55-55
.. gh-issue: 142754
.. nonce: xuCrt3
.. section: Library

Add the *ownerDocument* attribute to :mod:`xml.dom.minidom` elements and
attributes created by directly instantiating the ``Element`` or ``Attr``
class. Note that this way of creating nodes is not supported; creator
functions like :py:meth:`xml.dom.Document.documentElement` should be used
instead.

..

.. date: 2025-12-16-04-39-27
.. gh-issue: 142784
.. nonce: HBGJag
.. section: Library

The :mod:`asyncio` REPL now properly closes the loop upon the end of
interactive session. Previously, it could cause surprising warnings.
Contributed by Bartosz Sławecki.

..

.. date: 2025-12-15-02-02-45
.. gh-issue: 142555
.. nonce: EC9QN_
.. section: Library

:mod:`array`: fix a crash in ``a[i] = v`` when converting *i* to an index
via :meth:`i.__index__ <object.__index__>` or :meth:`i.__float__
<object.__float__>` mutates the array.

..

.. date: 2025-12-14-18-30-48
.. gh-issue: 142594
.. nonce: belDmD
.. section: Library

Fix crash in ``TextIOWrapper.close()`` when the underlying buffer's
``closed`` property calls :meth:`~io.TextIOBase.detach`.

..

.. date: 2025-12-14-10-00-23
.. gh-issue: 142451
.. nonce: _rkf2S
.. section: Library

:mod:`hmac`: Ensure that the :attr:`HMAC.block_size <hmac.HMAC.block_size>`
attribute is correctly copied by :meth:`HMAC.copy <hmac.HMAC.copy>`. Patch
by Bénédikt Tran.

..

.. date: 2025-12-13-23-26-42
.. gh-issue: 142495
.. nonce: I88Uv_
.. section: Library

:class:`collections.defaultdict` now prioritizes :meth:`~object.__setitem__`
when inserting default values from ``default_factory``. This prevents race
conditions where a default value would overwrite a value set before
``default_factory`` returns.

..

.. date: 2025-12-13-06-17-44
.. gh-issue: 142651
.. nonce: ZRtBu4
.. section: Library

:mod:`unittest.mock`: fix a thread safety issue where :attr:`Mock.call_count
<unittest.mock.Mock.call_count>` may return inaccurate values when the mock
is called concurrently from multiple threads.

..

.. date: 2025-12-12-02-56-26
.. gh-issue: 142595
.. nonce: wHvTqq
.. section: Library

Added type check during initialization of the :mod:`decimal` module to
prevent a crash in case of broken stdlib.  Patch by Sergey B Kirpichev.

..

.. date: 2025-12-11-09-03-07
.. gh-issue: 142556
.. nonce: RuiBte
.. section: Library

Fix crash when a task gets re-registered during finalization in
:mod:`asyncio`. Patch by Kumar Aditya.

..

.. date: 2025-12-10-11-20-05
.. gh-issue: 123241
.. nonce: oYg2n7
.. section: Library

Avoid reference count operations in garbage collection of :mod:`ctypes`
objects.

..

.. date: 2025-12-10-10-00-06
.. gh-issue: 142517
.. nonce: fG4hbe
.. section: Library

The non-``compat32`` :mod:`email` policies now correctly handle refolding
encoded words that contain bytes that can not be decoded in their specified
character set.  Previously this resulted in an encoding exception during
folding.

..

.. date: 2025-12-09-14-40-45
.. gh-issue: 112527
.. nonce: Tvf5Zk
.. section: Library

The help text for required options in :mod:`argparse` no longer extended
with " (default: None)".

..

.. date: 2025-12-07-17-30-05
.. gh-issue: 142346
.. nonce: okcAAp
.. section: Library

Fix usage formatting for mutually exclusive groups in :mod:`argparse` when
they are preceded by positional arguments or followed or intermixed with
other optional arguments.

..

.. date: 2025-12-07-02-36-24
.. gh-issue: 142315
.. nonce: 02o5E_
.. section: Library

Pdb can now run scripts from anonymous pipes used in process substitution.
Patch by Bartosz Sławecki.

..

.. date: 2025-12-06-13-02-13
.. gh-issue: 142332
.. nonce: PNvXCV
.. section: Library

Fix usage formatting for positional arguments in mutually exclusive groups
in :mod:`argparse`. in :mod:`argparse`.

..

.. date: 2025-12-05-18-26-50
.. gh-issue: 142282
.. nonce: g6RQUN
.. section: Library

Fix :func:`winreg.QueryValueEx` to not accidentally read garbage buffer
under race condition.

..

.. date: 2025-12-05-16-39-17
.. gh-issue: 75949
.. nonce: pHxW98
.. section: Library

Fix :mod:`argparse` to preserve ``|`` separators in mutually exclusive
groups when the usage line wraps due to length.

..

.. date: 2025-12-04-23-26-12
.. gh-issue: 142267
.. nonce: yOM6fP
.. section: Library

Improve :mod:`argparse` performance by caching the formatter used for
argument validation.

..

.. date: 2025-12-04-09-22-31
.. gh-issue: 68552
.. nonce: I_v-xB
.. section: Library

``MisplacedEnvelopeHeaderDefect`` and ``Missing header name`` defects are
now correctly passed to the ``handle_defect`` method of ``policy`` in
:class:`~email.parser.FeedParser`.

..

.. date: 2025-11-27-10-49-13
.. gh-issue: 142006
.. nonce: nzJDG5
.. section: Library

Fix a bug in the :mod:`email.policy.default` folding algorithm which
incorrectly resulted in a doubled newline when a line ending at exactly
max_line_length was followed by an unfoldable token.

..

.. date: 2025-11-18-15-48-13
.. gh-issue: 105836
.. nonce: sbUw24
.. section: Library

Fix :meth:`asyncio.run_coroutine_threadsafe` leaving underlying cancelled
asyncio task running.

..

.. date: 2025-10-12-12-05-52
.. gh-issue: 139971
.. nonce: UdoStU
.. section: Library

:mod:`pydoc`: Ensure that the link to the online documentation of a
:term:`stdlib` module is correct.

..

.. date: 2025-09-23-16-41-21
.. gh-issue: 139262
.. nonce: RO0E98
.. section: Library

Some keystrokes can be swallowed in the new ``PyREPL`` on Windows,
especially when used together with the ALT key. Fix by Chris Eibl.

..

.. date: 2025-09-14-22-26-50
.. gh-issue: 138897
.. nonce: vnUb_L
.. section: Library

Improved :data:`license`/:data:`copyright`/:data:`credits` display in the
:term:`REPL`: now uses a pager.

..

.. date: 2025-07-29-11-37-22
.. gh-issue: 79986
.. nonce: fnJbE_
.. section: Library

Add parsing for ``References`` and ``In-Reply-To`` headers to the
:mod:`email` library that parses the header content as lists of message id
tokens.  This prevents them from being folded incorrectly.

..

.. date: 2025-07-05-08-30-07
.. gh-issue: 136282
.. nonce: K3JKyD
.. section: Library

Add support for :const:`~configparser.UNNAMED_SECTION` when creating a
section via the mapping protocol access

..

.. date: 2025-06-22-18-57-19
.. gh-issue: 109263
.. nonce: f92V95
.. section: Library

Starting a process from spawn context in :mod:`multiprocessing` no longer
sets the start method globally.

..

.. date: 2025-05-05-10-41-41
.. gh-issue: 133253
.. nonce: J5-xDD
.. section: Library

Fix thread-safety issues in :mod:`linecache`.

..

.. date: 2025-04-19-17-34-11
.. gh-issue: 132715
.. nonce: XXl47F
.. section: Library

Skip writing objects during marshalling once a failure has occurred.

..

.. date: 2026-01-13-01-21-20
.. gh-issue: 143774
.. nonce: rqGwX1
.. section: IDLE

Better explain the operation of Format / Format Paragraph.

..

.. date: 2025-10-30-19-28-42
.. gh-issue: 140806
.. nonce: RBT9YH
.. section: Documentation

Add documentation for :func:`enum.bin`.

..

.. date: 2026-01-29-02-18-08
.. gh-issue: 144307
.. nonce: CLbm_o
.. section: Core and Builtins

Prevent a reference leak in module teardown at interpreter finalization.

..

.. date: 2026-01-23-20-20-42
.. gh-issue: 144194
.. nonce: IbXfxd
.. section: Core and Builtins

Fix error handling in perf jitdump initialization on memory allocation
failure.

..

.. date: 2026-01-19-02-33-45
.. gh-issue: 144012
.. nonce: wVEEWs
.. section: Core and Builtins

Check if the result is ``NULL`` in ``BINARY_OP_EXTENT`` opcode.

..

.. date: 2026-01-13-22-26-49
.. gh-issue: 141805
.. nonce: QzIKPS
.. section: Core and Builtins

Fix crash in :class:`set` when objects with the same hash are concurrently
added to the set after removing an element with the same hash while the set
still contains elements with the same hash.

..

.. date: 2026-01-11-20-11-36
.. gh-issue: 143670
.. nonce: klnGoD
.. section: Core and Builtins

Fixes a crash in ``ga_repr_items_list`` function.

..

.. date: 2026-01-04-16-56-17
.. gh-issue: 143377
.. nonce: YJqMCa
.. section: Core and Builtins

Fix a crash in :func:`!_interpreters.capture_exception` when the exception
is incorrectly formatted. Patch by Bénédikt Tran.

..

.. date: 2026-01-03-14-02-11
.. gh-issue: 136924
.. nonce: UMgdPn
.. section: Core and Builtins

The interactive help mode in the :term:`REPL` no longer incorrectly syntax
highlights text input as Python code. Contributed by Olga Matoula.

..

.. date: 2025-12-30-06-48-48
.. gh-issue: 143189
.. nonce: in_sv2
.. section: Core and Builtins

Fix crash when inserting a non-:class:`str` key into a split table
dictionary when the key matches an existing key in the split table but has
no corresponding value in the dict.

..

.. date: 2025-12-27-23-57-43
.. gh-issue: 143228
.. nonce: m3EF9E
.. section: Core and Builtins

Fix use-after-free in perf trampoline when toggling profiling while threads
are running or during interpreter finalization with daemon threads active.
The fix uses reference counting to ensure trampolines are not freed while
any code object could still reference them. Pach by Pablo Galindo

..

.. date: 2025-12-27-13-18-12
.. gh-issue: 142664
.. nonce: peeEDV
.. section: Core and Builtins

Fix a use-after-free crash in :meth:`memoryview.__hash__ <object.__hash__>`
when the ``__hash__`` method of the referenced object mutates that object or
the view. Patch by Bénédikt Tran.

..

.. date: 2025-12-27-12-25-06
.. gh-issue: 142557
.. nonce: KWOc8b
.. section: Core and Builtins

Fix a use-after-free crash in :ref:`bytearray.__mod__ <bytes-formatting>`
when the :class:`!bytearray` is mutated while formatting the ``%``-style
arguments. Patch by Bénédikt Tran.

..

.. date: 2025-12-27-10-14-26
.. gh-issue: 143195
.. nonce: MNldfr
.. section: Core and Builtins

Fix use-after-free crashes in :meth:`bytearray.hex` and
:meth:`memoryview.hex` when the separator's :meth:`~object.__len__` mutates
the original object. Patch by Bénédikt Tran.

..

.. date: 2025-12-24-13-44-24
.. gh-issue: 142975
.. nonce: 8C4vIP
.. section: Core and Builtins

Fix crash after unfreezing all objects tracked by the garbage collector on
the :term:`free threaded <free threading>` build.

..

.. date: 2025-12-24-11-39-59
.. gh-issue: 143135
.. nonce: 3d5ovx
.. section: Core and Builtins

Set :data:`sys.flags.inspect` to ``1`` when :envvar:`PYTHONINSPECT` is
``0``. Previously, it was set to ``0`` in this case.

..

.. date: 2025-12-23-00-13-02
.. gh-issue: 143003
.. nonce: 92g5qW
.. section: Core and Builtins

Fix an overflow of the shared empty buffer in :meth:`bytearray.extend` when
``__length_hint__()`` returns 0 for non-empty iterator.

..

.. date: 2025-12-22-22-37-53
.. gh-issue: 143006
.. nonce: ZBQwbN
.. section: Core and Builtins

Fix a possible assertion error when comparing negative non-integer ``float``
and ``int`` with the same number of bits in the integer part.

..

.. date: 2025-12-22-12-03-09
.. gh-issue: 143057
.. nonce: Majsre
.. section: Core and Builtins

Avoid locking in :c:func:`PyTraceMalloc_Track` and
:c:func:`PyTraceMalloc_Untrack` when :mod:`tracemalloc` is not enabled.

..

.. date: 2025-12-18-01-00-14
.. gh-issue: 142776
.. nonce: ACaoeP
.. section: Core and Builtins

Fix a file descriptor leak in import.c

..

.. date: 2025-12-17-19-45-10
.. gh-issue: 142829
.. nonce: ICtLXy
.. section: Core and Builtins

Fix a use-after-free crash in :class:`contextvars.Context` comparison when a
custom ``__eq__`` method modifies the context via
:meth:`~contextvars.ContextVar.set`.

..

.. date: 2025-12-16-11-56-20
.. gh-issue: 142766
.. nonce: Uy2HTm
.. section: Core and Builtins

Clear the frame of a generator when :meth:`generator.close` is called.

..

.. date: 2025-12-15-15-01-21
.. gh-issue: 142737
.. nonce: xYXzeB
.. section: Core and Builtins

Tracebacks will be displayed in fallback mode even if :func:`io.open` is
lost. Previously, this would crash the interpreter. Patch by Bartosz
Sławecki.

..

.. date: 2025-12-13-17-20-38
.. gh-issue: 142554
.. nonce: wNtEFF
.. section: Core and Builtins

Fix a crash in :func:`divmod` when :func:`!_pylong.int_divmod` does not
return a tuple of length two exactly. Patch by Bénédikt Tran.

..

.. date: 2025-12-11-22-59-33
.. gh-issue: 142560
.. nonce: GkJrkk
.. section: Core and Builtins

Fix use-after-free in :class:`bytearray` search-like methods
(:meth:`~bytearray.find`, :meth:`~bytearray.count`,
:meth:`~bytearray.index`, :meth:`~bytearray.rindex`, and
:meth:`~bytearray.rfind`) by marking the storage as exported which causes
reallocation attempts to raise :exc:`BufferError`. For
:func:`~operator.contains`, :meth:`~bytearray.split`, and
:meth:`~bytearray.rsplit` the :ref:`buffer protocol <bufferobjects>` is used
for this.

..

.. date: 2025-12-10-23-03-10
.. gh-issue: 142531
.. nonce: NUEa1T
.. section: Core and Builtins

Fix a free-threaded GC performance regression.  If there are many untracked
tuples, the GC will run too often, resulting in poor performance.  The fix
is to include untracked tuples in the "long lived" object count. The number
of frozen objects is also now included since the free-threaded GC must scan
those too.

..

.. date: 2025-12-08-17-34-57
.. gh-issue: 142402
.. nonce: iV0ON3
.. section: Core and Builtins

Fix reference counting when adjacent literal parts are merged while
constructing :class:`string.templatelib.Template`, preventing the displaced
string object from leaking.

..

.. date: 2025-12-08-15-46-06
.. gh-issue: 133932
.. nonce: HAxa4p
.. section: Core and Builtins

Fix crash in the free threading build when clearing frames that hold tagged
integers.

..

.. date: 2025-12-08-13-04-37
.. gh-issue: 142343
.. nonce: BTAyML
.. section: Core and Builtins

Fix SIGILL crash on m68k due to incorrect assembly constraint.

..

.. date: 2025-11-06-05-21-25
.. gh-issue: 100964
.. nonce: TxPf1b
.. section: Core and Builtins

Fix reference cycle in exhausted generator frames. Patch by Savannah
Ostrowski.

..

.. date: 2025-09-30-21-59-56
.. gh-issue: 69605
.. nonce: qcmGF3
.. section: Core and Builtins

Fix edge-cases around already imported modules in the :term:`REPL`
auto-completion of imports.

..

.. date: 2025-09-06-08-29-08
.. gh-issue: 138568
.. nonce: iZlalC
.. section: Core and Builtins

Adjusted the built-in :func:`help` function so that empty inputs are ignored
in interactive mode.

..

.. date: 2025-07-22-16-20-06
.. gh-issue: 137007
.. nonce: 1oPvvK
.. section: Core and Builtins

Fix a bug during JIT compilation failure which caused garbage collection
debug assertions to fail.

..

.. date: 2025-12-11-13-01-49
.. gh-issue: 142589
.. nonce: nNAqgw
.. section: C API

Fix :c:func:`PyUnstable_Object_IsUniqueReferencedTemporary()` handling of
tagged ints on the interpreter stack.

..

.. date: 2025-12-11-09-06-36
.. gh-issue: 142571
.. nonce: Csdxnn
.. section: C API

:c:func:`!PyUnstable_CopyPerfMapFile` now checks that opening the file
succeeded before flushing.

..

.. date: 2025-12-09-13-33-46
.. gh-issue: 142454
.. nonce: cqUxzQ
.. section: Build

When calculating the digest of the JIT stencils input, sort the hashed files
by filenames before adding their content to the hasher. This ensures
deterministic hash input and hence deterministic hash, independent on
filesystem order.

..

.. date: 2025-11-20-23-15-39
.. gh-issue: 141808
.. nonce: NEewZC
.. section: Build

When running ``make clean-retain-profile``, keep the generated JIT stencils.
That way, the stencils are not generated twice when Profile-guided
optimization (PGO) is used. It also allows distributors to supply their own
pre-built JIT stencils.

..

.. date: 2025-08-27-09-52-45
.. gh-issue: 138061
.. nonce: fMVS9w
.. section: Build

Ensure reproducible builds by making JIT stencil header generation
deterministic.
