macOS

• gh-97897 [https://github.com/python/cpython/issues/97897]: The macOS 13 SDK includes support for the mkfifoat and mknodat system calls. Using the dir_fd option with either os.mkfifo() or os.mknod() could result in a segfault if cpython is built with the macOS 13 SDK but run on an earlier version of macOS. Prevent this by adding runtime support for detection of these system calls ("weaklinking") as is done for other newer syscalls on macOS.

IDLE

• gh-97527 [https://github.com/python/cpython/issues/97527]: Fix a bug in the previous bugfix that caused IDLE to not start when run with 3.10.8, 3.12.0a1, and at least Microsoft Python 3.10.2288.0 installed without the Lib/test package. 3.11.0 was never affected.

• gh-65802 [https://github.com/python/cpython/issues/65802]: Document handling of extensions in Save As dialogs.

• gh-95191 [https://github.com/python/cpython/issues/95191]: Include prompts when saving Shell (interactive input and output).

• gh-95511 [https://github.com/python/cpython/issues/95511]: Fix the Shell context menu copy-with-prompts bug of copying an extra line when one selects whole lines.

• gh-95471 [https://github.com/python/cpython/issues/95471]: In the Edit menu, move Select All and add a new separator.

• gh-95411 [https://github.com/python/cpython/issues/95411]: Enable using IDLE's module browser with .pyw files.

• gh-89610 [https://github.com/python/cpython/issues/89610]: Add .pyi as a recognized extension for IDLE on macOS. This allows opening stub files by double clicking on them in the Finder.

工具/示例

• gh-68686 [https://github.com/python/cpython/issues/68686]: Remove ptags and eptags scripts.

• gh-97681 [https://github.com/python/cpython/issues/97681]: Remove the Tools/demo/ directory which contained old demo scripts. A copy can be found in the old-demos project [https://github.com/gvanrossum/old-demos]. Patch by Victor Stinner.

• gh-97669 [https://github.com/python/cpython/issues/97669]: Remove outdated example scripts of the Tools/scripts/ directory. A copy can be found in the old-demos project [https://github.com/gvanrossum/old-demos]. Patch by Victor Stinner.

• gh-95853 [https://github.com/python/cpython/issues/95853]: The wasm_build.py script now pre-builds Emscripten ports, checks for broken EMSDK versions, and warns about pkg-config env vars.

• gh-95853 [https://github.com/python/cpython/issues/95853]: The new tool Tools/wasm/wasm_builder.py automates configure, compile, and test steps for building CPython on WebAssembly platforms.

• gh-95731 [https://github.com/python/cpython/issues/95731]: Fix handling of module docstrings in Tools/i18n/pygettext.py.

• gh-93939 [https://github.com/python/cpython/issues/93939]: Add script Tools/scripts/check_modules.py to check and validate builtin and shared extension modules. The script also handles Modules/Setup and will eventually replace setup.py.

• gh-94538 [https://github.com/python/cpython/issues/94538]: Fix Argument Clinic output to custom file destinations. Patch by Erlend E. Aasland.

• gh-94430 [https://github.com/python/cpython/issues/94430]: Allow parameters named module and self with custom C names in Argument Clinic. Patch by Erlend E. Aasland

• gh-86087 [https://github.com/python/cpython/issues/86087]: The Tools/scripts/parseentities.py script used to parse HTML4 entities has been removed.

C API

• gh-98393 [https://github.com/python/cpython/issues/98393]: The PyUnicode_FSDecoder() function no longer accepts bytes-like paths, like bytearray and memoryview types: only the exact bytes type is accepted for bytes strings. Patch by Victor Stinner.

• gh-91051 [https://github.com/python/cpython/issues/91051]: Add PyType_Watch() and related APIs to allow callbacks on PyType_Modified().

• gh-95756 [https://github.com/python/cpython/issues/95756]: Lazily create and cache co_ attributes for better performance for code getters.

• gh-96512 [https://github.com/python/cpython/issues/96512]: Configuration for the integer string conversion length limitation now lives in the PyConfig C API struct.

• gh-95589 [https://github.com/python/cpython/issues/95589]: Extensions classes that set tp_dictoffset and tp_weaklistoffset lose the support for multiple inheritance, but are now safe. Extension classes should use Py_TPFLAGS_MANAGED_DICT and Py_TPFLAGS_MANAGED_WEAKREF instead.

• gh-95781 [https://github.com/python/cpython/issues/95781]: An unrecognized format character in PyUnicode_FromFormat() and PyUnicode_FromFormatV() now sets a SystemError. In previous versions it caused all the rest of the format string to be copied as-is to the result string, and any extra arguments discarded.

• gh-92678 [https://github.com/python/cpython/issues/92678]: Restore the 3.10 behavior for multiple inheritance of C extension classes that store their dictionary at the end of the struct.

• gh-92678 [https://github.com/python/cpython/issues/92678]: Support C extensions using managed dictionaries by setting the Py_TPFLAGS_MANAGED_DICT flag.

• gh-93274 [https://github.com/python/cpython/issues/93274]: API for implementing vectorcall (Py_TPFLAGS_HAVE_VECTORCALL, PyVectorcall_NARGS() and PyVectorcall_Call()) was added to the limited API and stable ABI.

• gh-95504 [https://github.com/python/cpython/issues/95504]: Fix sign placement when specifying width or precision in PyUnicode_FromFormat() and PyUnicode_FromFormatV(). Patch by Philip Georgi.

• gh-93012 [https://github.com/python/cpython/issues/93012]: The Py_TPFLAGS_HAVE_VECTORCALL flag is now removed from a class when the class's __call__() method is reassigned. This makes vectorcall safe to use with mutable types (i.e. heap types without the immutable flag). Mutable types that do not override tp_call now inherit the Py_TPFLAGS_HAVE_VECTORCALL flag.

• gh-95388 [https://github.com/python/cpython/issues/95388]: Creating immutable types with mutable bases is deprecated and is planned to be disabled in Python 3.14.

• gh-92678 [https://github.com/python/cpython/issues/92678]: Adds unstable C-API functions PyObjectVisitManagedDict and PyObjectClearManagedDict to allow C extensions to allow the VM to manage their object's dictionaries.

• gh-94936 [https://github.com/python/cpython/issues/94936]: Added PyCode_GetVarnames(), PyCode_GetCellvars() and PyCode_GetFreevars() for accessing co_varnames, co_cellvars and co_freevars respectively via the C API.

• gh-94930 [https://github.com/python/cpython/issues/94930]: Fix SystemError raised when PyArg_ParseTupleAndKeywords() is used with # in (…) but without PY_SSIZE_T_CLEAN defined.

• gh-94731 [https://github.com/python/cpython/issues/94731]: Python again uses C-style casts for most casting operations when compiled with C++. This may trigger compiler warnings, if they are enabled with e.g. -Wold-style-cast or -Wzero-as-null-pointer-constant options for g++.

• gh-93937 [https://github.com/python/cpython/issues/93937]: The following frame functions and type are now directly available with #include , it's no longer needed to add #include :

  • PyFrame_Check()

  • PyFrame_GetBack()

  • PyFrame_GetBuiltins()

  • PyFrame_GetGenerator()

  • PyFrame_GetGlobals()

  • PyFrame_GetLasti()

  • PyFrame_GetLocals()

  • PyFrame_Type

Patch by Victor Stinner.

• gh-91321 [https://github.com/python/cpython/issues/91321]: Fix the compatibility of the Python C API with C++ older than C++11. Patch by Victor Stinner.

• gh-91731 [https://github.com/python/cpython/issues/91731]: Avoid defining the static_assert when compiling with C++ 11, where this is a keyword and redefining it can lead to undefined behavior. Patch by Pablo Galindo

• gh-89546 [https://github.com/python/cpython/issues/89546]: PyType_FromMetaclass() (and other PyType_From* functions) now check that offsets and the base class's tp_basicsize fit in the new class's tp_basicsize.

• gh-93503 [https://github.com/python/cpython/issues/93503]: Add two new public functions to the public C-API, PyEval_SetProfileAllThreads() and PyEval_SetTraceAllThreads(), that allow to set tracing and profiling functions in all running threads in addition to the calling one. Also, two analogous functions to the threading module (threading.setprofile_all_threads() and threading.settrace_all_threads()) that allow to do the same from Python. Patch by Pablo Galindo

• gh-93442 [https://github.com/python/cpython/issues/93442]: Add C++ overloads for PyCAST_impl() to handle 0/NULL. This will allow C++ extensions that pass 0 or NULL to macros using PyCAST() to continue to compile.

• gh-93466 [https://github.com/python/cpython/issues/93466]: Slot IDs in PyType_Spec may not be repeated. The documentation was updated to mention this. For some cases of repeated slots, PyType_FromSpec and related functions will now raise an exception.

• gh-92898 [https://github.com/python/cpython/issues/92898]: Fix C++ compiler warnings when casting function arguments to PyObject*. Patch by Serge Guelton.

• gh-93103 [https://github.com/python/cpython/issues/93103]: Deprecate global configuration variables, like Py_IgnoreEnvironmentFlag, in the documentation: the Py_InitializeFromConfig() API should be instead. Patch by Victor Stinner.

• gh-77782 [https://github.com/python/cpython/issues/77782]: Deprecate global configuration variable like Py_IgnoreEnvironmentFlag: the Py_InitializeFromConfig() API should be instead. Patch by Victor Stinner.

• gh-92913 [https://github.com/python/cpython/issues/92913]: Ensures changes to PyConfig.module_search_paths are ignored unless PyConfig.module_search_paths_set is set

• gh-92781 [https://github.com/python/cpython/issues/92781]: Avoid mixing declarations and code in the C API to fix the compiler warning: "ISO C90 forbids mixed declarations and code" [-Werror=declaration-after-statement]. Patch by Victor Stinner.

• gh-92651 [https://github.com/python/cpython/issues/92651]: Remove the token.h header file. There was never any public tokenizer C API. The token.h header file was only designed to be used by Python internals. Patch by Victor Stinner.

• gh-92536 [https://github.com/python/cpython/issues/92536]: Remove legacy Unicode APIs based on Py_UNICODE*.

• gh-85858 [https://github.com/python/cpython/issues/85858]: Remove the PyUnicode_InternImmortal() function and the SSTATE_INTERNED_IMMORTAL macro. Patch by Victor Stinner.

• gh-92193 [https://github.com/python/cpython/issues/92193]: Add new function PyFunction_SetVectorcall() to the C API which sets the vectorcall field of a given PyFunctionObject.

Warning: extensions using this API must preserve the behavior of the unaltered function!

• gh-59121 [https://github.com/python/cpython/issues/59121]: Fixed an assert that prevented PyRun_InteractiveOne from providing tracebacks when parsing from the provided FD.

• bpo-45383 [https://bugs.python.org/issue?@action=redirect&bpo=45383]: The PyType_FromSpec() API will now find and use a metaclass based on the provided bases. An error will be raised if there is a metaclass conflict.

Python 3.11.0 beta 1

Release date: 2022-05-06

安全性

• gh-57684 [https://github.com/python/cpython/issues/57684]: Add the -P command line option and the PYTHONSAFEPATH environment variable to not prepend a potentially unsafe path to sys.path. Patch by Victor Stinner.

核心与内置函数

• gh-89519 [https://github.com/python/cpython/issues/89519]: Chaining classmethod descriptors (introduced in bpo-19072 [https://bugs.python.org/issue?@action=redirect&bpo=19072]) is deprecated. It can no longer be used to wrap other descriptors such as property(). The core design of this feature was flawed, and it caused a number of downstream problems.

• gh-92345 [https://github.com/python/cpython/issues/92345]: pymainrunpython() now imports readline and rlcompleter before sys.path is extended to include the current working directory of an interactive interpreter. Non-interactive interpreters are not affected.

• bpo-43857 [https://bugs.python.org/issue?@action=redirect&bpo=43857]: Improve the AttributeError message when deleting a missing attribute. Patch by Géry Ogam.

• gh-92245 [https://github.com/python/cpython/issues/92245]: Make sure that PEP 523 is respected in all cases. In 3.11a7, specialization may have prevented Python-to-Python calls respecting PEP 523.

• gh-92203 [https://github.com/python/cpython/issues/92203]: Add a closure keyword-only parameter to exec(). It can only be specified when exec-ing a code object that uses free variables. When specified, it must be a tuple, with exactly the number of cell variables referenced by the code object. closure has a default value of None, and it must be None if the code object doesn't refer to any free variables.

• gh-91173 [https://github.com/python/cpython/issues/91173]: Disable frozen modules in debug builds. Patch by Kumar Aditya.

• gh-92114 [https://github.com/python/cpython/issues/92114]: Improve error message when subscript a type with __class_getitem__ set to None.

• gh-92112 [https://github.com/python/cpython/issues/92112]: Fix crash triggered by an evil custom mro() on a metaclass.

• gh-92063 [https://github.com/python/cpython/issues/92063]: The PRECALL_METHOD_DESCRIPTOR_FAST_WITH_KEYWORDS instruction now ensures methods are called only on objects of the correct type.

• gh-92031 [https://github.com/python/cpython/issues/92031]: Deoptimize statically allocated code objects during Py_FINALIZE() so that future PyCodeQuicken calls always start with unquickened code.

• gh-92036 [https://github.com/python/cpython/issues/92036]: Fix a crash in subinterpreters related to the garbage collector. When a subinterpreter is deleted, untrack all objects tracked by its GC. To prevent a crash in deallocator functions expecting objects to be tracked by the GC, leak a strong reference to these objects on purpose, so they are never deleted and their deallocator functions are not called. Patch by Victor Stinner.

• gh-92032 [https://github.com/python/cpython/issues/92032]: The interpreter can now autocomplete soft keywords, as of now match, case, and _ (wildcard pattern) from PEP 634 [https://peps.python.org/pep-0634/].

• gh-87999 [https://github.com/python/cpython/issues/87999]: The warning emitted by the Python parser for a numeric literal immediately followed by keyword has been changed from deprecation warning to syntax warning.

• gh-91869 [https://github.com/python/cpython/issues/91869]: Fix an issue where specialized opcodes with extended arguments could produce incorrect tracing output or lead to assertion failures.

• gh-91603 [https://github.com/python/cpython/issues/91603]: Speed up types.UnionType instantiation. Based on patch provided by Yurii Karabas.

• gh-89373 [https://github.com/python/cpython/issues/89373]: If Python is built in debug mode, Python now ensures that deallocator functions leave the current exception unchanged. Patch by Victor Stinner.

• gh-91632 [https://github.com/python/cpython/issues/91632]: Fix a minor memory leak at exit: release the memory of the generic_alias_iterator type. Patch by Donghee Na.

• gh-81548 [https://github.com/python/cpython/issues/81548]: Octal escapes with value larger than 0o377 now produce a DeprecationWarning. In a future Python version they will be a SyntaxWarning and eventually a SyntaxError.

• bpo-43950 [https://bugs.python.org/issue?@action=redirect&bpo=43950]: Use a single compact table for line starts, ends and column offsets. Reduces memory consumption for location info by half

• gh-91102 [https://github.com/python/cpython/issues/91102]: Use Argument Clinic for EncodingMap. Patch by Oleg Iarygin.

• gh-91636 [https://github.com/python/cpython/issues/91636]: Fixed a crash in a garbage-collection edge-case, in which a PyFunction_Type.tp_clear function could leave a python function object in an inconsistent state.

• gh-91603 [https://github.com/python/cpython/issues/91603]: Speed up isinstance() and issubclass() checks for types.UnionType. Patch by Yurii Karabas.

• gh-91625 [https://github.com/python/cpython/issues/91625]: Fixed a bug in which adaptive opcodes ignored any preceding EXTENDED_ARGs on specialization failure.

• gh-78607 [https://github.com/python/cpython/issues/78607]: The LLTRACE special build now looks for the name __lltrace__ defined in module globals, rather than the name __ltrace__, which had been introduced as a typo.

• gh-91576 [https://github.com/python/cpython/issues/91576]: Speed up iteration of ascii strings by 50%. Patch by Kumar Aditya.

• gh-89279 [https://github.com/python/cpython/issues/89279]: Improve interpreter performance on Windows by inlining a few specific macros.

• gh-91502 [https://github.com/python/cpython/issues/91502]: Add a new PyFrameIsEntryFrame() API function, to check if a PyFrameObject is an entry frame. Patch by Pablo Galindo.

• gh-91266 [https://github.com/python/cpython/issues/91266]: Refactor the bytearray strip methods strip, lstrip and rstrip to use a common implementation.

• gh-91479 [https://github.com/python/cpython/issues/91479]: Replaced the __note__ field of BaseException (added in an earlier version of 3.11) with the final design of PEP 678 [https://peps.python.org/pep-0678/]. Namely, BaseException gets an add_note() method, and its __notes__ field is created when necessary.

• gh-46055 [https://github.com/python/cpython/issues/46055]: Speed up right shift of negative integers, by removing unnecessary creation of temporaries. Original patch by Xinhang Xu, reworked by Mark Dickinson.

• gh-91462 [https://github.com/python/cpython/issues/91462]: Make the interpreter's low-level tracing (lltrace) feature output more readable by displaying opcode names (rather than just numbers), and by displaying stack contents before each opcode.

• gh-89455 [https://github.com/python/cpython/issues/89455]: Fixed an uninitialized bool value in the traceback printing code path that was introduced by the initial bpo-45292 [https://bugs.python.org/issue?@action=redirect&bpo=45292] exception groups work.

• gh-91421 [https://github.com/python/cpython/issues/91421]: Fix a potential integer overflow in PyDecodeUTF8Ex.

• gh-91428 [https://github.com/python/cpython/issues/91428]: Add static const char *const PyOpcodeOpName[256] = {…}; to opcode.h for debug builds to assist in debugging the Python interpreter. It is now more convenient to make various forms of debugging output more human-readable by including opcode names rather than just the corresponding decimal digits.

• bpo-47120 [https://bugs.python.org/issue?@action=redirect&bpo=47120]: Make POP_JUMP_IF_TRUE, POP_JUMP_IF_FALSE, POP_JUMP_IF_NONE and POP_JUMP_IF_NOT_NONE virtual, mapping to new relative jump opcodes.

• bpo-45317 [https://bugs.python.org/issue?@action=redirect&bpo=45317]: Add internal documentation explaining design of new (for 3.11) frame stack.

• bpo-47197 [https://bugs.python.org/issue?@action=redirect&bpo=47197]: ctypes used to mishandle void return types, so that for instance a function declared like ctypes.CFUNCTYPE(None, ctypes.c_int) would be called with signature int f(int) instead of void f(int). Wasm targets require function pointers to be called with the correct signatures so this led to crashes. The problem is now fixed.

• bpo-47120 [https://bugs.python.org/issue?@action=redirect&bpo=47120]: Make opcodes JUMP_IF_TRUE_OR_POP and JUMP_IF_FALSE_OR_POP relative rather than absolute.

• bpo-47177 [https://bugs.python.org/issue?@action=redirect&bpo=47177]: Replace the f_lasti member of the internal _PyInterpreterFrame structure with a prev_instr pointer, which reduces overhead in the main interpreter loop. The f_lasti attribute of Python-layer frame objects is preserved for backward-compatibility.

• bpo-46961 [https://bugs.python.org/issue?@action=redirect&bpo=46961]: Integer mod/remainder operations, including the three-argument form of pow(), now consistently return ints from the global small integer cache when applicable.

• bpo-46962 [https://bugs.python.org/issue?@action=redirect&bpo=46962]: Classes and functions that unconditionally declared their docstrings ignoring the --without-doc-strings compilation flag no longer do so.

The classes affected are ctypes.UnionType, pickle.PickleBuffer, testcapi.RecursingInfinitelyError, and types.GenericAlias.

The functions affected are 24 methods in ctypes.

Patch by Oleg Iarygin.

• bpo-46942 [https://bugs.python.org/issue?@action=redirect&bpo=46942]: Use Argument Clinic for the types.MethodType constructor. Patch by Oleg Iarygin.

• bpo-46764 [https://bugs.python.org/issue?@action=redirect&bpo=46764]: Fix wrapping bound methods with @classmethod

• bpo-43464 [https://bugs.python.org/issue?@action=redirect&bpo=43464]: Optimize set.intersection() for non-set arguments.

• bpo-46721 [https://bugs.python.org/issue?@action=redirect&bpo=46721]: Optimize set.issuperset() for non-set argument.

• bpo-46509 [https://bugs.python.org/issue?@action=redirect&bpo=46509]: Add type-specialized versions of the Py_DECREF(), and use them for float, int, str, bool, and None to avoid pointer-chasing at runtime where types are known at C compile time.

• bpo-46045 [https://bugs.python.org/issue?@action=redirect&bpo=46045]: Do not use POSIX semaphores on NetBSD

• bpo-36819 [https://bugs.python.org/issue?@action=redirect&bpo=36819]: Fix crashes in builtin encoders with error handlers that return position less or equal than the starting position of non-encodable characters.

• bpo-34093 [https://bugs.python.org/issue?@action=redirect&bpo=34093]: marshal.dumps() uses FLAG_REF for all interned strings. This makes output more deterministic and helps reproducible build.

• bpo-26579 [https://bugs.python.org/issue?@action=redirect&bpo=26579]: Added object.__getstate__ which provides the default implementation of the __getstate__() method.

Copying and pickling instances of subclasses of builtin types bytearray, set, frozenset, collections.OrderedDict, collections.deque, weakref.WeakSet, and datetime.tzinfo now copies and pickles instance attributes implemented as slots.