.. date: 2025-11-04-19-20-05 .. gh-issue: 140849 .. nonce: YjB2ZZ .. release date: 2025-11-18 .. section: Windows Update bundled liblzma to version 5.8.1. .. .. date: 2025-11-12-12-54-28 .. gh-issue: 141442 .. nonce: 50dS3P .. section: Tools/Demos The iOS testbed now correctly handles test arguments that contain spaces. .. .. date: 2025-10-29-15-20-19 .. gh-issue: 140702 .. nonce: ZXtW8h .. section: Tools/Demos The iOS testbed app will now expose the ``GITHUB_ACTIONS`` environment variable to iOS apps being tested. .. .. date: 2025-09-21-10-30-08 .. gh-issue: 139198 .. nonce: Fm7NfU .. section: Tools/Demos Remove ``Tools/scripts/checkpip.py`` script. .. .. date: 2025-09-20-20-31-54 .. gh-issue: 139188 .. nonce: zfcxkW .. section: Tools/Demos Remove ``Tools/tz/zdump.py`` script. .. .. date: 2025-10-23-16-39-49 .. gh-issue: 140482 .. nonce: ZMtyeD .. section: Tests Preserve and restore the state of ``stty echo`` as part of the test environment. .. .. date: 2025-10-15-00-52-12 .. gh-issue: 140082 .. nonce: fpET50 .. section: Tests Update ``python -m test`` to set ``FORCE_COLOR=1`` when being run with color enabled so that :mod:`unittest` which is run by it with redirected output will output in color. .. .. date: 2025-07-09-21-45-51 .. gh-issue: 136442 .. nonce: jlbklP .. section: Tests Use exitcode ``1`` instead of ``5`` if :func:`unittest.TestCase.setUpClass` raises an exception .. .. date: 2025-08-15-23-08-44 .. gh-issue: 137836 .. nonce: b55rhh .. section: Security Add support of the "plaintext" element, RAWTEXT elements "xmp", "iframe", "noembed" and "noframes", and optionally RAWTEXT element "noscript" in :class:`html.parser.HTMLParser`. .. .. date: 2025-06-28-13-23-53 .. gh-issue: 136063 .. nonce: aGk0Jv .. section: Security :mod:`email.message`: ensure linear complexity for legacy HTTP parameters parsing. Patch by Bénédikt Tran. .. .. date: 2025-05-30-22-33-27 .. gh-issue: 136065 .. nonce: bu337o .. section: Security Fix quadratic complexity in :func:`os.path.expandvars`. .. .. date: 2025-11-14-16-24-20 .. gh-issue: 141497 .. nonce: L_CxDJ .. section: Library :mod:`ipaddress`: ensure that the methods :meth:`IPv4Network.hosts() ` and :meth:`IPv6Network.hosts() ` always return an iterator. .. .. date: 2025-11-13-14-51-30 .. gh-issue: 140938 .. nonce: kXsHHv .. section: Library The :func:`statistics.stdev` and :func:`statistics.pstdev` functions now raise a :exc:`ValueError` when the input contains an infinity or a NaN. .. .. date: 2025-11-12-15-42-47 .. gh-issue: 124111 .. nonce: hTw4OE .. section: Library Updated Tcl threading configuration in :mod:`_tkinter` to assume that threads are always available in Tcl 9 and later. .. .. date: 2025-11-12-01-49-03 .. gh-issue: 137109 .. nonce: D6sq2B .. section: Library The :mod:`os.fork` and related forking APIs will no longer warn in the common case where Linux or macOS platform APIs return the number of threads in a process and find the answer to be 1 even when a :func:`os.register_at_fork` ``after_in_parent=`` callback (re)starts a thread. .. .. date: 2025-11-10-01-47-18 .. gh-issue: 141314 .. nonce: baaa28 .. section: Library Fix assertion failure in :meth:`io.TextIOWrapper.tell` when reading files with standalone carriage return (``\r``) line endings. .. .. date: 2025-11-09-18-55-13 .. gh-issue: 141311 .. nonce: qZ3swc .. section: Library Fix assertion failure in :func:`!io.BytesIO.readinto` and undefined behavior arising when read position is above capcity in :class:`io.BytesIO`. .. .. date: 2025-11-08-13-03-10 .. gh-issue: 87710 .. nonce: XJeZlP .. section: Library :mod:`mimetypes`: Update mime type for ``.ai`` files to ``application/pdf``. .. .. date: 2025-11-07-12-25-46 .. gh-issue: 85524 .. nonce: 9SWFIC .. section: Library Update ``io.FileIO.readall``, an implementation of :meth:`io.RawIOBase.readall`, to follow :class:`io.IOBase` guidelines and raise :exc:`io.UnsupportedOperation` when a file is in "w" mode rather than :exc:`OSError` .. .. date: 2025-11-06-15-11-50 .. gh-issue: 141141 .. nonce: tgIfgH .. section: Library Fix a thread safety issue with :func:`base64.b85decode`. Contributed by Benel Tayar. .. .. date: 2025-11-04-20-08-41 .. gh-issue: 141018 .. nonce: d_oyOI .. section: Library :mod:`mimetypes`: Update ``.exe``, ``.dll``, ``.rtf`` and (when ``strict=False``) ``.jpg`` to their correct IANA mime type. .. .. date: 2025-11-04-15-40-35 .. gh-issue: 137969 .. nonce: 9VZQVt .. section: Library Fix :meth:`annotationlib.ForwardRef.evaluate` returning :class:`~annotationlib.ForwardRef` objects which don't update with new globals. .. .. date: 2025-11-04-12-16-13 .. gh-issue: 75593 .. nonce: EFVhKR .. section: Library Add support of :term:`path-like objects ` and :term:`bytes-like objects ` in :func:`wave.open`. .. .. date: 2025-11-03-16-23-54 .. gh-issue: 140797 .. nonce: DuFEeR .. section: Library The undocumented :class:`!re.Scanner` class now forbids regular expressions containing capturing groups in its lexicon patterns. Patterns using capturing groups could previously lead to crashes with segmentation fault. Use non-capturing groups (?:...) instead. .. .. date: 2025-11-03-05-38-31 .. gh-issue: 125115 .. nonce: jGS8MN .. section: Library Refactor the :mod:`pdb` parsing issue so positional arguments can pass through intuitively. .. .. date: 2025-11-02-19-23-32 .. gh-issue: 140815 .. nonce: McEG-T .. section: Library :mod:`faulthandler` now detects if a frame or a code object is invalid or freed. Patch by Victor Stinner. .. .. date: 2025-11-02-11-46-00 .. gh-issue: 100218 .. nonce: 9Ezfdq .. section: Library Correctly set :attr:`~OSError.errno` when :func:`socket.if_nametoindex` or :func:`socket.if_indextoname` raise an :exc:`OSError`. Patch by Bénédikt Tran. .. .. date: 2025-11-02-09-37-22 .. gh-issue: 140734 .. nonce: f8gST9 .. section: Library :mod:`multiprocessing`: fix off-by-one error when checking the length of a temporary socket file path. Patch by Bénédikt Tran. .. .. date: 2025-11-01-14-44-09 .. gh-issue: 140873 .. nonce: kfuc9B .. section: Library Add support of non-:term:`descriptor` callables in :func:`functools.singledispatchmethod`. .. .. date: 2025-11-01-00-36-14 .. gh-issue: 140874 .. nonce: eAWt3K .. section: Library Bump the version of pip bundled in ensurepip to version 25.3 .. .. date: 2025-11-01-00-34-53 .. gh-issue: 140826 .. nonce: JEDd7U .. section: Library Now :class:`!winreg.HKEYType` objects are compared by their underlying Windows registry handle value instead of their object identity. .. .. date: 2025-10-31-16-25-13 .. gh-issue: 140808 .. nonce: XBiQ4j .. section: Library The internal class ``mailbox._ProxyFile`` is no longer a parameterized generic. .. .. date: 2025-10-31-15-06-26 .. gh-issue: 140691 .. nonce: JzHGtg .. section: Library In :mod:`urllib.request`, when opening a FTP URL fails because a data connection cannot be made, the control connection's socket is now closed to avoid a :exc:`ResourceWarning`. .. .. date: 2025-10-31-13-57-55 .. gh-issue: 103847 .. nonce: VM7TnW .. section: Library Fix hang when cancelling process created by :func:`asyncio.create_subprocess_exec` or :func:`asyncio.create_subprocess_shell`. Patch by Kumar Aditya. .. .. date: 2025-10-30-15-33-07 .. gh-issue: 137821 .. nonce: 8_Iavt .. section: Library Convert ``_json`` module to use Argument Clinic. Patched by Yoonho Hann. .. .. date: 2025-10-30-12-36-19 .. gh-issue: 140790 .. nonce: _3T6-N .. section: Library Initialize all Pdb's instance variables in ``__init__``, remove some hasattr/getattr .. .. date: 2025-10-29-16-53-00 .. gh-issue: 140766 .. nonce: CNagKF .. section: Library Add :func:`enum.show_flag_values` and ``enum.bin`` to ``enum.__all__``. .. .. date: 2025-10-29-16-12-41 .. gh-issue: 120057 .. nonce: qGj5Dl .. section: Library Add :func:`os.reload_environ` to ``os.__all__``. .. .. date: 2025-10-29-09-40-10 .. gh-issue: 140741 .. nonce: L13UCV .. section: Library Fix ``profiling.sampling.sample()`` incorrectly handling a :exc:`FileNotFoundError` or :exc:`PermissionError`. .. .. date: 2025-10-28-17-43-51 .. gh-issue: 140228 .. nonce: 8kfHhO .. section: Library Avoid making unnecessary filesystem calls for frozen modules in :mod:`linecache` when the global module cache is not present. .. .. date: 2025-10-28-02-46-56 .. gh-issue: 139946 .. nonce: aN3_uY .. section: Library Error and warning keywords in ``argparse.ArgumentParser`` messages are now colorized when color output is enabled, fixing a visual inconsistency in which they remained plain text while other output was colorized. .. .. date: 2025-10-27-18-29-42 .. gh-issue: 140590 .. nonce: LT9HHn .. section: Library Fix arguments checking for the :meth:`!functools.partial.__setstate__` that may lead to internal state corruption and crash. Patch by Sergey Miryanov. .. .. date: 2025-10-27-16-01-41 .. gh-issue: 125434 .. nonce: qy0uRA .. section: Library Display thread name in :mod:`faulthandler` on Windows. Patch by Victor Stinner. .. .. date: 2025-10-27-13-49-31 .. gh-issue: 140634 .. nonce: ULng9G .. section: Library Fix a reference counting bug in :meth:`!os.sched_param.__reduce__`. .. .. date: 2025-10-27-00-40-49 .. gh-issue: 140650 .. nonce: DYJPJ9 .. section: Library Fix an issue where closing :class:`io.BufferedWriter` could crash if the closed attribute raised an exception on access or could not be converted to a boolean. .. .. date: 2025-10-26-16-24-12 .. gh-issue: 140633 .. nonce: ioayC1 .. section: Library Ignore :exc:`AttributeError` when setting a module's ``__file__`` attribute when loading an extension module packaged as Apple Framework. .. .. date: 2025-10-25-22-55-07 .. gh-issue: 140601 .. nonce: In3MlS .. section: Library :func:`xml.etree.ElementTree.iterparse` now emits a :exc:`ResourceWarning` when the iterator is not explicitly closed and was opened with a filename. This helps developers identify and fix resource leaks. Patch by Osama Abdelkader. .. .. date: 2025-10-25-21-26-16 .. gh-issue: 140593 .. nonce: OxlLc9 .. section: Library :mod:`xml.parsers.expat`: Fix a memory leak that could affect users with :meth:`~xml.parsers.expat.xmlparser.ElementDeclHandler` set to a custom element declaration handler. Patch by Sebastian Pipping. .. .. date: 2025-10-25-21-04-00 .. gh-issue: 140607 .. nonce: oOZGxS .. section: Library Inside :meth:`io.RawIOBase.read`, validate that the count of bytes returned by :meth:`io.RawIOBase.readinto` is valid (inside the provided buffer). .. .. date: 2025-10-23-19-39-16 .. gh-issue: 138162 .. nonce: Znw5DN .. section: Library Fix :class:`logging.LoggerAdapter` with ``merge_extra=True`` and without the *extra* argument. .. .. date: 2025-10-23-13-42-15 .. gh-issue: 140481 .. nonce: XKxWpq .. section: Library Improve error message when trying to iterate a Tk widget, image or font. .. .. date: 2025-10-23-12-12-22 .. gh-issue: 138774 .. nonce: mnh2gU .. section: Library :func:`ast.unparse` now generates full source code when handling :class:`ast.Interpolation` nodes that do not have a specified source. .. .. date: 2025-10-22-20-52-13 .. gh-issue: 140474 .. nonce: xIWlip .. section: Library Fix memory leak in :class:`array.array` when creating arrays from an empty :class:`str` and the ``u`` type code. .. .. date: 2025-10-22-12-56-57 .. gh-issue: 140448 .. nonce: GsEkXD .. section: Library Change the default of ``suggest_on_error`` to ``True`` in ``argparse.ArgumentParser``. .. .. date: 2025-10-21-15-54-13 .. gh-issue: 137530 .. nonce: ZyIVUH .. section: Library :mod:`dataclasses` Fix annotations for generated ``__init__`` methods by replacing the annotations that were in-line in the generated source code with ``__annotate__`` functions attached to the methods. .. .. date: 2025-10-20-12-33-49 .. gh-issue: 140348 .. nonce: SAKnQZ .. section: Library Fix regression in Python 3.14.0 where using the ``|`` operator on a :class:`typing.Union` object combined with an object that is not a type would raise an error. .. .. date: 2025-10-18-15-20-25 .. gh-issue: 76007 .. nonce: SNUzRq .. section: Library :mod:`decimal`: Deprecate ``__version__`` and replace with :data:`decimal.SPEC_VERSION`. .. .. date: 2025-10-18-14-30-21 .. gh-issue: 76007 .. nonce: peEgcr .. section: Library Deprecate ``__version__`` from :mod:`imaplib`. Patch by Hugo van Kemenade. .. .. date: 2025-10-17-23-58-11 .. gh-issue: 140272 .. nonce: lhY8uS .. section: Library Fix memory leak in the :meth:`!clear` method of the :mod:`dbm.gnu` database. .. .. date: 2025-10-17-20-42-38 .. gh-issue: 129117 .. nonce: X9jr4p .. section: Library :mod:`unicodedata`: Add :func:`~unicodedata.isxidstart` and :func:`~unicodedata.isxidcontinue` functions to check whether a character can start or continue a `Unicode Standard Annex #31 `_ identifier. .. .. date: 2025-10-17-12-33-01 .. gh-issue: 140251 .. nonce: esM-OX .. section: Library Colorize the default import statement ``import asyncio`` in asyncio REPL. .. .. date: 2025-10-16-22-49-16 .. gh-issue: 140212 .. nonce: llBNd0 .. section: Library Calendar's HTML formatting now accepts year and month as options. Previously, running ``python -m calendar -t html 2025 10`` would result in an error message. It now generates an HTML document displaying the calendar for the specified month. Contributed by Pål Grønås Drange. .. .. date: 2025-10-16-17-17-20 .. gh-issue: 135801 .. nonce: faH3fa .. section: Library Improve filtering by module in :func:`warnings.warn_explicit` if no *module* argument is passed. It now tests the module regular expression in the warnings filter not only against the filename with ``.py`` stripped, but also against module names constructed starting from different parent directories of the filename (with ``/__init__.py``, ``.py`` and, on Windows, ``.pyw`` stripped). .. .. date: 2025-10-16-16-10-11 .. gh-issue: 139707 .. nonce: zR6Qtn .. section: Library Improve :exc:`ModuleNotFoundError` error message when a :term:`standard library` module is missing. .. .. date: 2025-10-15-21-42-13 .. gh-issue: 140041 .. nonce: _Fka2j .. section: Library Fix import of :mod:`ctypes` on Android and Cygwin when ABI flags are present. .. .. date: 2025-10-15-20-47-04 .. gh-issue: 140120 .. nonce: 3gffZq .. section: Library Fixed a memory leak in :mod:`hmac` when it was using the hacl-star backend. Discovered by ``@ashm-dev`` using AddressSanitizer. .. .. date: 2025-10-15-17-23-51 .. gh-issue: 140141 .. nonce: j2mUDB .. section: Library The :py:class:`importlib.metadata.PackageNotFoundError` traceback raised when ``importlib.metadata.Distribution.from_name`` cannot discover a distribution no longer includes a transient :exc:`StopIteration` exception trace. Contributed by Bartosz Sławecki in :gh:`140142`. .. .. date: 2025-10-15-15-10-34 .. gh-issue: 140166 .. nonce: NtxRez .. section: Library :mod:`mimetypes`: Per the `IANA assignment `_, update the MIME type for the ``.texi`` and ``.texinfo`` file formats to ``application/texinfo``, instead of ``application/x-texinfo``. .. .. date: 2025-10-15-02-26-50 .. gh-issue: 140135 .. nonce: 54JYfM .. section: Library Speed up :meth:`io.RawIOBase.readall` by using PyBytesWriter API (about 4x faster) .. .. date: 2025-10-14-20-27-06 .. gh-issue: 76007 .. nonce: 2NcUbo .. section: Library :mod:`zlib`: Deprecate ``__version__`` and schedule for removal in Python 3.20. .. .. date: 2025-10-13-11-25-41 .. gh-issue: 136702 .. nonce: uvLGK1 .. section: Library :mod:`encodings`: Deprecate passing a non-ascii *encoding* name to :func:`encodings.normalize_encoding` and schedule removal of support for Python 3.17. .. .. date: 2025-10-11-09-07-06 .. gh-issue: 139940 .. nonce: g54efZ .. section: Library Print clearer error message when using ``pdb`` to attach to a non-existing process. .. .. date: 2025-10-02-22-29-00 .. gh-issue: 139462 .. nonce: VZXUHe .. section: Library When a child process in a :class:`concurrent.futures.ProcessPoolExecutor` terminates abruptly, the resulting traceback will now tell you the PID and exit code of the terminated process. Contributed by Jonathan Berg. .. .. date: 2025-09-30-12-52-54 .. gh-issue: 63161 .. nonce: mECM1A .. section: Library Fix :func:`tokenize.detect_encoding`. Support non-UTF-8 shebang and comments if non-UTF-8 encoding is specified. Detect decoding error for non-UTF-8 encoding. Detect null bytes in source code. .. .. date: 2025-09-25-20-16-10 .. gh-issue: 101828 .. nonce: yTxJlJ .. section: Library Fix ``'shift_jisx0213'``, ``'shift_jis_2004'``, ``'euc_jisx0213'`` and ``'euc_jis_2004'`` codecs truncating null chars as they were treated as part of multi-character sequences. .. .. date: 2025-09-23-09-46-46 .. gh-issue: 139246 .. nonce: pzfM-w .. section: Library fix: paste zero-width in default repl width is wrong. .. .. date: 2025-09-18-21-25-41 .. gh-issue: 83714 .. nonce: TQjDWZ .. section: Library Implement :func:`os.statx` on Linux kernel versions 4.11 and later with glibc versions 2.28 and later. Contributed by Jeffrey Bosboom and Victor Stinner. .. .. date: 2025-09-15-21-03-11 .. gh-issue: 138891 .. nonce: oZFdtR .. section: Library Fix ``SyntaxError`` when ``inspect.get_annotations(f, eval_str=True)`` is called on a function annotated with a :pep:`646` ``star_expression`` .. .. date: 2025-09-13-12-19-17 .. gh-issue: 138859 .. nonce: PxjIoN .. section: Library Fix generic type parameterization raising a :exc:`TypeError` when omitting a :class:`ParamSpec` that has a default which is not a list of types. .. .. date: 2025-09-12-09-34-37 .. gh-issue: 138764 .. nonce: mokHoY .. section: Library Prevent :func:`annotationlib.call_annotate_function` from calling ``__annotate__`` functions that don't support ``VALUE_WITH_FAKE_GLOBALS`` in a fake globals namespace with empty globals. Make ``FORWARDREF`` and ``STRING`` annotations fall back to using ``VALUE`` annotations in the case that neither their own format, nor ``VALUE_WITH_FAKE_GLOBALS`` are supported. .. .. date: 2025-09-11-15-03-37 .. gh-issue: 138775 .. nonce: w7rnSx .. section: Library Use of ``python -m`` with :mod:`base64` has been fixed to detect input from a terminal so that it properly notices EOF. .. .. date: 2025-09-03-20-18-39 .. gh-issue: 98896 .. nonce: tjez89 .. section: Library Fix a failure in multiprocessing resource_tracker when SharedMemory names contain colons. Patch by Rani Pinchuk. .. .. date: 2025-09-03-18-26-07 .. gh-issue: 138425 .. nonce: cVE9Ho .. section: Library Fix partial evaluation of :class:`annotationlib.ForwardRef` objects which rely on names defined as globals. .. .. date: 2025-08-26-08-17-56 .. gh-issue: 138151 .. nonce: I6CdAk .. section: Library In :mod:`annotationlib`, improve evaluation of forward references to nonlocal variables that are not yet defined when the annotations are initially evaluated. .. .. date: 2025-08-15-20-35-30 .. gh-issue: 69528 .. nonce: qc-Eh_ .. section: Library The :attr:`~io.FileIO.mode` attribute of files opened in the ``'wb+'`` mode is now ``'wb+'`` instead of ``'rb+'``. .. .. date: 2025-08-11-04-52-18 .. gh-issue: 137627 .. nonce: Ku5Yi2 .. section: Library Speed up :meth:`csv.Sniffer.sniff` delimiter detection by up to 1.6x. .. .. date: 2025-07-14-09-33-17 .. gh-issue: 55531 .. nonce: Gt2e12 .. section: Library :mod:`encodings`: Improve :func:`~encodings.normalize_encoding` performance by implementing the function in C using the private ``_Py_normalize_encoding`` which has been modified to make lowercase conversion optional. .. .. date: 2025-07-01-04-57-57 .. gh-issue: 136057 .. nonce: 4-t596 .. section: Library Fixed the bug in :mod:`pdb` and :mod:`bdb` where ``next`` and ``step`` can't go over the line if a loop exists in the line. .. .. date: 2025-06-29-22-01-00 .. gh-issue: 133390 .. nonce: I1DW_3 .. section: Library Support table, index, trigger, view, column, function, and schema completion for :mod:`sqlite3`'s :ref:`command-line interface `. .. .. date: 2025-06-10-18-02-29 .. gh-issue: 135307 .. nonce: fXGrcK .. section: Library :mod:`email`: Fix exception in ``set_content()`` when encoding text and max_line_length is set to ``0`` or ``None`` (unlimited). .. .. date: 2025-05-10-15-10-54 .. gh-issue: 133789 .. nonce: I-ZlUX .. section: Library Fix unpickling of :mod:`pathlib` objects that were pickled in Python 3.13. .. .. date: 2025-05-07-22-09-28 .. gh-issue: 133601 .. nonce: 9kUL3P .. section: Library Remove deprecated :func:`!typing.no_type_check_decorator`. .. .. date: 2025-04-18-18-08-05 .. gh-issue: 132686 .. nonce: 6kV_Gs .. section: Library Add parameters *inherit_class_doc* and *fallback_to_class_doc* for :func:`inspect.getdoc`. .. .. date: 2025-03-12-18-57-10 .. gh-issue: 131116 .. nonce: uTpwXZ .. section: Library :func:`inspect.getdoc` now correctly returns an inherited docstring on :class:`~functools.cached_property` objects if none is given in a subclass. .. .. date: 2025-03-04-17-19-26 .. gh-issue: 130693 .. nonce: Kv01r8 .. section: Library Add support for ``-nolinestop``, and ``-strictlimits`` options to :meth:`!tkinter.Text.search`. Also add the :meth:`!tkinter.Text.search_all` method for ``-all`` and ``-overlap`` options. .. .. date: 2024-08-08-12-39-36 .. gh-issue: 122255 .. nonce: J_gU8Y .. section: Library In the :mod:`linecache` module and in the Python implementation of the :mod:`warnings` module, a ``DeprecationWarning`` is issued when ``mod.__loader__`` differs from ``mod.__spec__.loader`` (like in the C implementation of the :mod:`!warnings` module). .. .. date: 2024-06-26-16-16-43 .. gh-issue: 121011 .. nonce: qW54eh .. section: Library :func:`math.log` now supports arbitrary large integer-like arguments in the same way as arbitrary large integer arguments. .. .. date: 2024-05-28-17-14-30 .. gh-issue: 119668 .. nonce: RrIGpn .. section: Library Publicly expose and document :class:`importlib.machinery.NamespacePath`. .. .. date: 2023-03-21-10-59-40 .. gh-issue: 102431 .. nonce: eUDnf4 .. section: Library Clarify constraints for "logical" arguments in methods of :class:`decimal.Context`. .. .. date: 2019-06-02-13-56-16 .. gh-issue: 81313 .. nonce: axawSH .. section: Library Add the :mod:`math.integer` module (:pep:`791`). .. .. date: 2025-11-15-01-21-00 .. gh-issue: 141579 .. nonce: aB7cD9 .. section: Core and Builtins Fix :func:`sys.activate_stack_trampoline` to properly support the ``perf_jit`` backend. Patch by Pablo Galindo. .. .. date: 2025-11-14-16-25-15 .. gh-issue: 114203 .. nonce: n3tlQO .. section: Core and Builtins Skip locking if object is already locked by two-mutex critical section. .. .. date: 2025-11-14-00-19-45 .. gh-issue: 141528 .. nonce: VWdax1 .. section: Core and Builtins Suggest using :meth:`concurrent.interpreters.Interpreter.close` instead of the private ``_interpreters.destroy`` function when warning about remaining subinterpreters. Patch by Sergey Miryanov. .. .. date: 2025-11-11-13-40-45 .. gh-issue: 141367 .. nonce: I5KY7F .. section: Core and Builtins Specialize ``CALL_LIST_APPEND`` instruction only for lists, not for list subclasses, to avoid unnecessary deopt. Patch by Mikhail Efimov. .. .. date: 2025-11-10-23-07-06 .. gh-issue: 141312 .. nonce: H-58GB .. section: Core and Builtins Fix the assertion failure in the ``__setstate__`` method of the range iterator when a non-integer argument is passed. Patch by Sergey Miryanov. .. .. date: 2025-11-05-19-50-37 .. gh-issue: 140643 .. nonce: QCEOqG .. section: Core and Builtins Add support for ```` and ```` frames to :mod:`!profiling.sampling` output to denote active garbage collection and calls to native code. .. .. date: 2025-11-04-12-18-06 .. gh-issue: 140942 .. nonce: GYns6n .. section: Library Add ``.cjs`` to :mod:`mimetypes` to give CommonJS modules a MIME type of ``application/node``. .. .. date: 2025-11-04-04-57-24 .. gh-issue: 140479 .. nonce: lwQ2v2 .. section: Core and Builtins Update JIT compilation to use LLVM 21 at build time. .. .. date: 2025-11-03-17-21-38 .. gh-issue: 140939 .. nonce: FVboAw .. section: Core and Builtins Fix memory leak when :class:`bytearray` or :class:`bytes` is formated with the ``%*b`` format with a large width that results in a :exc:`MemoryError`. .. .. date: 2025-11-02-15-28-33 .. gh-issue: 140260 .. nonce: JNzlGz .. section: Library Fix :mod:`struct` data race in endian table initialization with subinterpreters. Patch by Shamil Abdulaev. .. .. date: 2025-11-02-12-47-38 .. gh-issue: 140530 .. nonce: S934bp .. section: Core and Builtins Fix a reference leak when ``raise exc from cause`` fails. Patch by Bénédikt Tran. .. .. date: 2025-10-31-14-03-42 .. gh-issue: 90344 .. nonce: gvZigO .. section: Library Replace :class:`io.IncrementalNewlineDecoder` with non incremental newline decoders in codebase where :meth:`!io.IncrementalNewlineDecoder.decode` was being called once. .. .. date: 2025-10-29-20-59-10 .. gh-issue: 140373 .. nonce: -uoaPP .. section: Core and Builtins Correctly emit ``PY_UNWIND`` event when generator object is closed. Patch by Mikhail Efimov. .. .. date: 2025-10-29-11-31-59 .. gh-issue: 140729 .. nonce: t9JsNt .. section: Core and Builtins Fix pickling error in the sampling profiler when using ``concurrent.futures.ProcessPoolExecutor`` script can not be properly pickled and executed in worker processes. .. .. date: 2025-10-25-21-31-43 .. gh-issue: 131527 .. nonce: V-JVNP .. section: Core and Builtins Dynamic borrow checking for stackrefs is added to ``Py_STACKREF_DEBUG`` mode. Patch by Mikhail Efimov. .. .. date: 2025-10-25-17-36-46 .. gh-issue: 140576 .. nonce: kj0SCY .. section: Core and Builtins Fixed crash in :func:`tokenize.generate_tokens` in case of specific incorrect input. Patch by Mikhail Efimov. .. .. date: 2025-10-25-07-25-52 .. gh-issue: 140544 .. nonce: lwjtQe .. section: Core and Builtins Speed up accessing interpreter state by caching it in a thread local variable. Patch by Kumar Aditya. .. .. date: 2025-10-24-20-42-33 .. gh-issue: 140551 .. nonce: -9swrl .. section: Core and Builtins Fixed crash in :class:`dict` if :meth:`dict.clear` is called at the lookup stage. Patch by Mikhail Efimov and Inada Naoki. .. .. date: 2025-10-24-20-16-42 .. gh-issue: 140517 .. nonce: cqun-K .. section: Core and Builtins Fixed a reference leak when iterating over the result of :func:`map` with ``strict=True`` when the input iterables have different lengths. Patch by Mikhail Efimov. .. .. date: 2025-10-24-14-29-12 .. gh-issue: 133467 .. nonce: A5d6TM .. section: Core and Builtins Fix race when updating :attr:`!type.__bases__` that could allow a read of :attr:`!type.__base__` to observe an inconsistent value on the free threaded build. .. .. date: 2025-10-23-16-05-50 .. gh-issue: 140471 .. nonce: Ax_aXn .. section: Core and Builtins Fix potential buffer overflow in :class:`ast.AST` node initialization when encountering malformed :attr:`~ast.AST._fields` containing non-:class:`str`. .. .. date: 2025-10-22-23-26-37 .. gh-issue: 140443 .. nonce: wT5i1A .. section: Library The logarithm functions (such as :func:`math.log10` and :func:`math.log`) may now produce slightly different results for extremely large integers that cannot be converted to floats without overflow. These results are generally more accurate, with reduced worst-case error and a tighter overall error distribution. .. .. date: 2025-10-22-17-22-22 .. gh-issue: 140431 .. nonce: m8D_A- .. section: Core and Builtins Fix a crash in Python's :term:`garbage collector ` due to partially initialized :term:`coroutine` objects when coroutine origin tracking depth is enabled (:func:`sys.set_coroutine_origin_tracking_depth`). .. .. date: 2025-10-22-12-48-05 .. gh-issue: 140476 .. nonce: F3-d1P .. section: Core and Builtins Optimize :c:func:`PySet_Add` for :class:`frozenset` in :term:`free threaded ` build. .. .. date: 2025-10-22-11-30-16 .. gh-issue: 135904 .. nonce: 3WE5oW .. section: Core and Builtins Add special labels to the assembly created during stencil creation to support relocations that the native object file format does not support. Specifically, 19 bit branches for AArch64 in Mach-O object files. .. .. date: 2025-10-21-09-20-03 .. gh-issue: 140398 .. nonce: SoABwJ .. section: Library Fix memory leaks in :mod:`readline` functions :func:`~readline.read_init_file`, :func:`~readline.read_history_file`, :func:`~readline.write_history_file`, and :func:`~readline.append_history_file` when :c:func:`PySys_Audit` fails. .. .. date: 2025-10-21-06-51-50 .. gh-issue: 140406 .. nonce: 0gJs8M .. section: Core and Builtins Fix memory leak when an object's :meth:`~object.__hash__` method returns an object that isn't an :class:`int`. .. .. date: 2025-10-20-11-24-36 .. gh-issue: 140358 .. nonce: UQuKdV .. section: Core and Builtins Restore elapsed time and unreachable object count in GC debug output. These were inadvertently removed during a refactor of ``gc.c``. The debug log now again reports elapsed collection time and the number of unreachable objects. Contributed by Pål Grønås Drange. .. .. date: 2025-10-19-10-32-28 .. gh-issue: 136895 .. nonce: HfsEh0 .. section: Core and Builtins Update JIT compilation to use LLVM 20 at build time. .. .. date: 2025-10-18-21-50-44 .. gh-issue: 139109 .. nonce: 9QQOzN .. section: Core and Builtins A new tracing frontend for the JIT compiler has been implemented. Patch by Ken Jin. Design for CPython by Ken Jin, Mark Shannon and Brandt Bucher. .. .. date: 2025-10-18-21-29-45 .. gh-issue: 140306 .. nonce: xS5CcS .. section: Core and Builtins Fix memory leaks in cross-interpreter channel operations and shared namespace handling. .. .. date: 2025-10-18-19-52-20 .. gh-issue: 116738 .. nonce: NLJW0L .. section: Core and Builtins Make _suggestions module thread-safe on the :term:`free threaded ` build. .. .. date: 2025-10-18-18-08-36 .. gh-issue: 140301 .. nonce: m-2HxC .. section: Core and Builtins Fix memory leak of ``PyConfig`` in subinterpreters. .. .. date: 2025-10-17-20-23-19 .. gh-issue: 140257 .. nonce: 8Txmem .. section: Core and Builtins Fix data race between interpreter_clear() and take_gil() on eval_breaker during finalization with daemon threads. .. .. date: 2025-10-17-18-03-12 .. gh-issue: 139951 .. nonce: IdwM2O .. section: Core and Builtins Fixes a regression in GC performance for a growing heap composed mostly of small tuples. * Counts number of actually tracked objects, instead of trackable objects. This ensures that untracking tuples has the desired effect of reducing GC overhead. * Does not track most untrackable tuples during creation. This prevents large numbers of small tuples causing excessive GCs. .. .. date: 2025-10-17-14-38-10 .. gh-issue: 140253 .. nonce: gCqFaL .. section: Core and Builtins Wrong placement of a double-star pattern inside a mapping pattern now throws a specialized syntax error. Contributed by Bartosz Sławecki in :gh:`140253`. .. .. date: 2025-10-16-21-47-00 .. gh-issue: 140104 .. nonce: A8SQIm .. section: Core and Builtins Fix a bug with exception handling in the JIT. Patch by Ken Jin. Bug reported by Daniel Diniz. .. .. date: 2025-10-15-17-12-32 .. gh-issue: 140149 .. nonce: cy1m3d .. section: Core and Builtins Speed up parsing bytes literals concatenation by using PyBytesWriter API and a single memory allocation (about 3x faster). .. .. date: 2025-10-15-00-21-40 .. gh-issue: 140061 .. nonce: J0XeDV .. section: Core and Builtins Fixing the checking of whether an object is uniquely referenced to ensure free-threaded compatibility. Patch by Sergey Miryanov. .. .. date: 2025-10-14-20-18-31 .. gh-issue: 140080 .. nonce: 8ROjxW .. section: Core and Builtins Fix hang during finalization when attempting to call :mod:`atexit` handlers under no memory. .. .. date: 2025-10-14-18-24-16 .. gh-issue: 139871 .. nonce: SWtuUz .. section: Core and Builtins Update :class:`bytearray` to use a :class:`bytes` under the hood as its buffer and add :meth:`bytearray.take_bytes` to take it out. .. .. date: 2025-10-14-17-07-37 .. gh-issue: 140067 .. nonce: ID2gOm .. section: Core and Builtins Fix memory leak in sub-interpreter creation. .. .. date: 2025-10-13-13-54-19 .. gh-issue: 139914 .. nonce: M-y_3E .. section: Core and Builtins Restore support for HP PA-RISC, which has an upwards-growing stack. .. .. date: 2025-10-12-01-12-12 .. gh-issue: 139817 .. nonce: PAn-8Z .. section: Core and Builtins Attribute ``__qualname__`` is added to :class:`typing.TypeAliasType`. Patch by Mikhail Efimov. .. .. date: 2025-10-06-14-19-47 .. gh-issue: 135801 .. nonce: OhxEZS .. section: Core and Builtins Many functions related to compiling or parsing Python code, such as :func:`compile`, :func:`ast.parse`, :func:`symtable.symtable`, and :func:`importlib.abc.InspectLoader.source_to_code` now allow to specify the module name. It is needed to unambiguous :ref:`filter ` syntax warnings by module name. .. .. date: 2025-10-06-10-03-37 .. gh-issue: 139640 .. nonce: gY5oTb2 .. section: Core and Builtins :func:`ast.parse` no longer emits syntax warnings for ``return``/``break``/``continue`` in ``finally`` (see :pep:`765`) -- they are only emitted during compilation. .. .. date: 2025-10-06-10-03-37 .. gh-issue: 139640 .. nonce: gY5oTb .. section: Core and Builtins Fix swallowing some syntax warnings in different modules if they accidentally have the same message and are emitted from the same line. Fix duplicated warnings in the ``finally`` block. .. .. date: 2025-10-03-17-51-43 .. gh-issue: 139475 .. nonce: _684ED .. section: Core and Builtins Changes in stackref debugging mode when ``Py_STACKREF_DEBUG`` is set. We use the same pattern of refcounting for stackrefs as in production build. .. .. date: 2025-09-23-21-01-12 .. gh-issue: 139269 .. nonce: 1rIaxy .. section: Core and Builtins Fix undefined behavior when using unaligned store in JIT's ``patch_*`` functions. .. .. date: 2025-09-15-13-06-11 .. gh-issue: 138944 .. nonce: PeCgLb .. section: Core and Builtins Fix :exc:`SyntaxError` message when invalid syntax appears on the same line as a valid ``import ... as ...`` or ``from ... import ... as ...`` statement. Patch by Brian Schubert. .. .. date: 2025-09-13-01-23-25 .. gh-issue: 138857 .. nonce: YQ5gdc .. section: Core and Builtins Improve :exc:`SyntaxError` message for ``case`` keyword placed outside :keyword:`match` body. .. .. date: 2025-07-29-17-51-14 .. gh-issue: 131253 .. nonce: GpRjWy .. section: Core and Builtins Support the ``--enable-pystats`` build option for the free-threaded build. .. .. date: 2025-07-08-00-41-46 .. gh-issue: 136327 .. nonce: 7AiTb_ .. section: Core and Builtins Errors when calling functions with invalid values after ``*`` and ``**`` now do not include the function name. Patch by Ilia Solin. .. .. date: 2025-06-24-13-12-58 .. gh-issue: 134786 .. nonce: MF0VVk .. section: Core and Builtins If :c:macro:`Py_TPFLAGS_MANAGED_DICT` and :c:macro:`Py_TPFLAGS_MANAGED_WEAKREF` are used, then :c:macro:`Py_TPFLAGS_HAVE_GC` must be used as well. .. .. date: 2025-11-10-11-26-26 .. gh-issue: 141341 .. nonce: OsO6-y .. section: C API On Windows, rename the ``COMPILER`` macro to ``_Py_COMPILER`` to avoid name conflicts. Patch by Victor Stinner. .. .. date: 2025-11-08-10-51-50 .. gh-issue: 116146 .. nonce: pCmx6L .. section: C API Add a new :c:func:`PyImport_CreateModuleFromInitfunc` C-API for creating a module from a *spec* and *initfunc*. Patch by Itamar Oren. .. .. date: 2025-11-06-06-28-14 .. gh-issue: 141042 .. nonce: brOioJ .. section: C API Make qNaN in :c:func:`PyFloat_Pack2` and :c:func:`PyFloat_Pack4`, if while conversion to a narrower precision floating-point format --- the remaining after truncation payload will be zero. Patch by Sergey B Kirpichev. .. .. date: 2025-11-05-05-45-49 .. gh-issue: 141004 .. nonce: N9Ooh9 .. section: C API :c:macro:`!Py_MATH_El` and :c:macro:`!Py_MATH_PIl` are deprecated. .. .. date: 2025-11-05-04-38-16 .. gh-issue: 141004 .. nonce: rJL43P .. section: C API The :c:macro:`!Py_INFINITY` macro is :term:`soft deprecated`. .. .. date: 2025-10-26-16-45-28 .. gh-issue: 140556 .. nonce: s__Dae .. section: C API :pep:`793`: Add a new entry point for C extension modules, ``PyModExport_``. .. .. date: 2025-10-26-16-45-06 .. gh-issue: 140487 .. nonce: fGOqss .. section: C API Fix :c:macro:`Py_RETURN_NOTIMPLEMENTED` in limited C API 3.11 and older: don't treat ``Py_NotImplemented`` as immortal. Patch by Victor Stinner. .. .. date: 2025-10-15-15-59-59 .. gh-issue: 140153 .. nonce: BO7sH4 .. section: C API Fix :c:func:`Py_REFCNT` definition on limited C API 3.11-3.13. Patch by Victor Stinner. .. .. date: 2025-10-06-22-17-47 .. gh-issue: 139653 .. nonce: 6-1MOd .. section: C API Add :c:func:`PyUnstable_ThreadState_SetStackProtection` and :c:func:`PyUnstable_ThreadState_ResetStackProtection` functions to set the stack protection base address and stack protection size of a Python thread state. Patch by Victor Stinner. .. .. date: 2025-10-31-13-20-16 .. gh-issue: 140454 .. nonce: gF6dCe .. section: Build When building the JIT, match the jit_stencils filename expectations in Makefile with the generator script. This avoid needless JIT recompilation during ``make install``. .. .. date: 2025-10-29-12-30-38 .. gh-issue: 140768 .. nonce: ITYrzw .. section: Build Warn when the WASI SDK version doesn't match what's supported. .. .. date: 2025-10-25-08-07-06 .. gh-issue: 140513 .. nonce: 6OhLTs .. section: Build Generate a clear compilation error when ``_Py_TAIL_CALL_INTERP`` is enabled but either ``preserve_none`` or ``musttail`` is not supported. .. .. date: 2025-10-22-12-44-07 .. gh-issue: 140475 .. nonce: OhzQbR .. section: Build Support WASI SDK 25. .. .. date: 2025-10-17-11-33-45 .. gh-issue: 140239 .. nonce: _k-GgW .. section: Build Check ``statx`` availability only on Linux (including Android). .. .. date: 2025-10-16-11-30-53 .. gh-issue: 140189 .. nonce: YCrUyt .. section: Build iOS builds were added to CI. .. .. date: 2025-08-10-22-28-06 .. gh-issue: 137618 .. nonce: FdNvIE .. section: Build ``PYTHON_FOR_REGEN`` now requires Python 3.10 to Python 3.15. Patch by Adam Turner.