Registro de cambios¶
Python next¶
Release date: XXXX-XX-XX
Core and Builtins¶
gh-89987: Reduce the number of inline
CACHE
entries forBINARY_SUBSCR
.gh-102859: Removed
JUMP_IF_FALSE_OR_POP
andJUMP_IF_TRUE_OR_POP
instructions.gh-101975: Fixed
stacktop
value on tracing entries to avoid corruption on garbage collection.gh-102778: Add
sys.last_exc
and deprecatesys.last_type
,sys.last_value
andsys.last_traceback
, which hold the same information in its legacy form.gh-100982: Replace all occurrences of
COMPARE_AND_BRANCH
withCOMPARE_OP
.gh-102701: Fix overflow when creating very large dict.
gh-102755: Add
PyErr_DisplayException()
which takes just an exception instance, to replace the legacyPyErr_Display()
which takes the(typ, exc, tb)
triplet.gh-102594: Add note to exception raised in
PyErr_SetObject
when normalization fails.gh-90997: Shrink the number of inline
CACHE
entries used byLOAD_GLOBAL
.gh-102491: Improve import time of
platform
by removing IronPython version parsing. The IronPython version parsing was not functional (see https://github.com/IronLanguages/ironpython3/issues/1667).gh-101291: Rearrage bits in first field (after header) of PyLongObject. * Bits 0 and 1: 1 - sign. I.e. 0 for positive numbers, 1 for zero and 2 for negative numbers. * Bit 2 reserved (probably for the immortal bit) * Bits 3+ the unsigned size.
This makes a few operations slightly more efficient, and will enable a more compact and faster 2s-complement representation of most ints in future.
gh-102397: Fix segfault from race condition in signal handling during garbage collection. Patch by Kumar Aditya.
gh-102406:
codecs
encoding/decoding errors now get the context information (which operation and which codecs) attached as PEP 678 notes instead of through chaining a new instance of the exception.gh-102281: Fix potential nullptr dereference and use of uninitialized memory in fileutils. Patch by Max Bachmann.
gh-102300: Reuse operands with refcount of 1 in float specializations of BINARY_OP.
gh-102213: Fix performance loss when accessing an object’s attributes with
__getattr__
defined.gh-102255: Improve build support for the Xbox. Patch by Max Bachmann.
gh-102027: Fix SSE2 and SSE3 detection in
_blake2
internal module. Patch by Max Bachmann.
Library¶
gh-103085: Pure python
locale.getencoding()
will not warn deprecation.gh-103068: It’s no longer possible to register conditional breakpoints in
Pdb
that raiseSyntaxError
. Patch by Tian Gao.gh-102549: Don’t ignore exceptions in member type creation.
gh-103056: Ensure final
_generate_next_value_
is astaticmethod
.gh-103046: Display current line label correctly in
dis
whenshow_caches
is False andlasti
points to a CACHE entry.gh-103023: It’s no longer possible to register expressions to display in
Pdb
that raiseSyntaxError
. Patch by Tian Gao.gh-102947: Improve traceback when
dataclasses.fields()
is called on a non-dataclass. Patch by Alex Waygoodgh-102780: The
asyncio.Timeout
context manager now works reliably even when performing cleanup due to task cancellation. Previously it could raise aCancelledError
instead of anTimeoutError
in such cases.gh-102871: Remove support for obsolete browsers from
webbrowser
. Removed browsers include Grail, Mosaic, Netscape, Galeon, Skipstone, Iceape, Firebird, and Firefox versions 35 and below.gh-102839: Improve performance of
math.log()
arguments handling by removing the argument clinic.gh-102828: Add the
onexc
arg toshutil.rmtree()
, which is likeonerror
but expects an exception instance rather than an exc_info tuple. Deprecateonerror
.gh-88965: typing: Fix a bug relating to substitution in custom classes generic over a
ParamSpec
. Previously, if theParamSpec
was substituted with a parameters list that itself contained aTypeVar
, theTypeVar
in the parameters list could not be subsequently substituted. This is now fixed.Patch by Nikita Sobolev.
gh-78530:
asyncio.wait()
now accepts generators yielding tasks. Patch by Kumar Aditya.gh-102748:
asyncio.iscoroutine()
now returnsFalse
for generators asasyncio
does not support legacy generator-based coroutines. Patch by Kumar Aditya.gh-102670: Optimized fmean(), correlation(), covariance(), and linear_regression() using the new math.sumprod() function.
gh-102615: Typing: Improve the
repr
of generic aliases for classes generic over aParamSpec
. (Use square brackets to represent a parameter list.)gh-100112:
asyncio.Task.get_coro()
now always returns a coroutine when wrapping an awaitable object. Patch by Kumar Aditya.gh-102578: Speed up setting or deleting mutable attributes on non-dataclass subclasses of frozen dataclasses. Due to the implementation of
__setattr__
and__delattr__
for frozen dataclasses, this previously had a time complexity ofO(n)
. It now has a time complexity ofO(1)
.gh-102519: Add
os.listdrives()
,os.listvolumes()
andos.listmounts()
functions on Windows for enumerating drives, volumes and mount pointsgh-74468: Attribute name of the extracted
tarfile
file object now holds filename of itself rather than of the archive it is contained in. Patch by Oleg Iarygin.gh-102378: Private helper method
inspect._signature_strip_non_python_syntax
will no longer strip/
from the input string.gh-79940: Add
inspect.getasyncgenstate()
andinspect.getasyncgenlocals()
. Patch by Thomas Krennwallner.gh-102103: Add
module
argument todataclasses.make_dataclass()
and make classes produced by it pickleable.gh-102069: Fix
__weakref__
descriptor generation for custom dataclasses.gh-98886: Fix issues when defining dataclasses that have fields with specific underscore names that aren’t clearly reserved by
dataclasses
.gh-101673: Fix a
pdb
bug wherell
clears the changes to local variables.gh-101313: Added -h and –help arguments to the webbrowser CLI
gh-100372:
ssl.SSLContext.load_verify_locations()
no longer incorrectly accepts some cases of trailing data when parsing DER.gh-89727: Fix pathlib.Path.walk RecursionError on deep directory trees by rewriting it using iteration instead of recursion.
gh-100131: Added an optional
delete
keyword argument totempfile.TemporaryDirectory
.gh-98169: Fix
dataclasses.astuple()
crash whencollections.defaultdict
is present in the attributes.gh-96931: Fix incorrect results from
ssl.SSLSocket.shared_ciphers()
gh-95495: When built against OpenSSL 3.0, the
ssl
module had a bug where it reported unauthenticated EOFs (i.e. without close_notify) as a clean TLS-level EOF. It now raisesSSLEOFError
, matching the behavior in previous versions of OpenSSL. Theoptions
attribute onSSLContext
also no longer includesOP_IGNORE_UNEXPECTED_EOF
by default. This option may be set to specify the previous OpenSSL 3.0 behavior.gh-94684: Now
uuid.uuid3()
anduuid.uuid5()
functions supportbytes
objects as their name argument.gh-94440: Fix a
concurrent.futures.process
bug whereProcessPoolExecutor
shutdown could hang after a future has been quickly submitted and canceled.gh-72346: Added deprecation warning to isdst parameter of
email.utils.localtime()
.bpo-36305: Fix handling of Windows filenames that resemble drives, such as
./a:b
, inpathlib
.
Documentation¶
gh-103112: Add docstring to
http.client.HTTPResponse.read()
to fixpydoc
output.
Tests¶
Build¶
Windows¶
gh-102690: Update
webbrowser
to fall back to Microsoft Edge instead of Internet Explorer.gh-99726: Improves correctness of stat results for Windows, and uses faster API when available
Tools/Demos¶
gh-102809:
Misc/gdbinit
was removed.
C API¶
gh-102013: Add a new (unstable) C-API function for iterating over GC’able objects using a callback:
PyUnstable_VisitObjects
.
Python 3.12.0 alpha 6¶
Release date: 2023-03-07
Security¶
gh-99108: Replace builtin hashlib implementations of MD5 and SHA1 with verified ones from the HACL* project.
gh-101727: Updated the OpenSSL version used in Windows and macOS binary release builds to 1.1.1t to address CVE-2023-0286, CVE-2022-4303, and CVE-2022-4303 per the OpenSSL 2023-02-07 security advisory.
gh-99108: Replace the builtin
hashlib
implementations of SHA2-384 and SHA2-512 originally from LibTomCrypt with formally verified, side-channel resistant code from the HACL* project. The builtins remain a fallback only used when OpenSSL does not provide them.gh-101283:
subprocess.Popen
now uses a safer approach to findcmd.exe
when launching withshell=True
. Patch by Eryk Sun, based on a patch by Oleg Iarygin.
Core and Builtins¶
gh-102493: Fix regression in semantics of normalisation in
PyErr_SetObject
.gh-102416: Do not memoize incorrectly automatically generated loop rules in the parser. Patch by Pablo Galindo.
gh-102356: Fix a bug that caused a crash when deallocating deeply nested filter objects. Patch by Marta Gómez Macías.
gh-102336: Cleanup Windows 7 specific special handling. Patch by Max Bachmann.
gh-102250: Fixed a segfault occurring when the interpreter calls a
__bool__
method that raises.gh-102126: Fix deadlock at shutdown when clearing thread states if any finalizer tries to acquire the runtime head lock. Patch by Kumar Aditya.
gh-102027: Use
GetCurrentProcessId
on Windows whengetpid
is unavailable. Patch by Max Bachmann.gh-102056: Fix error handling bugs in interpreter’s exception printing code, which could cause a crash on infinite recursion.
gh-100982: Restrict the scope of the
FOR_ITER_RANGE
instruction to the scope of the originalFOR_ITER
instruction, to allow instrumentation.gh-101967: Fix possible segfault in
positional_only_passed_as_keyword
function, when new list created.gh-101952: Fix possible segfault in
BUILD_SET
opcode, when new set created.gh-74895:
socket.getaddrinfo
no longer raisesOverflowError
forint
port values outside of the C long range. Out of range values are left up to the underlying string based C library API to report. Asocket.gaierror
SAI_SERVICE
may occur instead, or no error at all as not all platform C libraries generate an error.gh-101799: Add
CALL_INTRINSIC_2
and use it instead ofPREP_RERAISE_STAR
.gh-101857: Fix xattr support detection on Linux systems by widening the check to linux, not just glibc. This fixes support for musl.
gh-84783: Make the slice object hashable. Patch by Will Bradshaw and Furkan Onder.
gh-87849: Change the
SEND
instruction to leave the receiver on the stack. This allows the specialized form ofSEND
to skip the chain of C calls and jump directly to theRESUME
in the generator or coroutine.gh-101765: Fix SystemError / segmentation fault in iter
__reduce__
when internal access ofbuiltins.__dict__
keys mutates the iter object.gh-101430: Update
tracemalloc
to handle presize of object properly. Patch by Dong-hee Na.gh-101696: Invalidate type version tag in
_PyStaticType_Dealloc
for static types, avoiding bug where a false cache hit could crash the interpreter. Patch by Kumar Aditya.gh-101632: Adds a new
RETURN_CONST
instruction.gh-100719: Remove gi_code field from generator (and coroutine and async generator) objects as it is redundant. The frame already includes a reference to the code object.
gh-98627: When an interpreter is configured to check (and only then), importing an extension module will now fail when the extension does not support multiple interpreters (i.e. doesn’t implement PEP 489 multi-phase init). This does not apply to the main interpreter, nor to subinterpreters created with
Py_NewInterpreter()
.
Library¶
gh-102302: Micro-optimise hashing of
inspect.Parameter
, reducing the time it takes to hash an instance by around 40%.gh-101979: Fix a bug where parentheses in the
metavar
argument toargparse.ArgumentParser.add_argument()
were dropped. Patch by Yeojin Kim.gh-91038:
platform.platform()
now has boolean default arguments.gh-81652: Add
mmap.MAP_ALIGNED_SUPER
FreeBSD andmmap.MAP_CONCEAL
OpenBSD constants tommap
. Patch by Yeojin Kim.gh-101961: For the binary mode,
fileinput.hookcompressed()
doesn’t set theencoding
value even if the value isNone
. Patch by Gihwan Kim.gh-101936: The default value of
fp
becomesio.BytesIO
ifHTTPError
is initialized without a designatedfp
parameter. Patch by Long Vo.gh-101566: In zipfile, sync Path with zipp 3.14, including fix for extractall on the underlying zipfile after being wrapped in
Path
.gh-97930: Apply changes from importlib_resources 5.12, including fix for
MultiplexedPath
to support directories in multiple namespaces (python/importlib_resources#265).gh-101997: Upgrade pip wheel bundled with ensurepip (pip 23.0.1)
gh-99108: The built-in extension modules for
hashlib
SHA2 algorithms, used when OpenSSL does not provide them, now live in a single internal_sha2
module instead of separate_sha256
and_sha512
modules.gh-101892: Callable iterators no longer raise
SystemError
when the callable object exhausts the iterator but forgets to either return a sentinel value or raiseStopIteration
.gh-87634: Remove locking behavior from
functools.cached_property()
.gh-97786: Fix potential undefined behaviour in corner cases of floating-point-to-time conversions.
gh-101517: Fixed bug where
bdb
looks up the source line withlinecache
with alineno=None
, which causes it to fail with an unhandled exception.gh-101773: Optimize
fractions.Fraction
for small components. The private argument_normalize
of thefractions.Fraction
constructor has been removed.gh-101693: In
sqlite3.Cursor.execute()
,DeprecationWarning
is now emitted when named placeholders are used together with parameters supplied as a sequence instead of as adict
. Starting from Python 3.14, using named placeholders with parameters supplied as a sequence will raise aProgrammingError
. Patch by Erlend E. Aasland.gh-101446: Change repr of
collections.OrderedDict
to use regular dictionary formating instead of pairs of keys and values.gh-101362: Speed up
pathlib.PurePath
construction by handling arguments more uniformly. When apathlib.Path
argument is supplied, we use its string representation rather than joining its parts withos.path.join()
.gh-101362: Speed up
pathlib.PurePath
construction by callingos.path.join()
only when two or more arguments are given.gh-101362: Speed up
pathlib.Path
construction by running the path flavour compatibility check only when pathlib is imported.gh-85984: Refactored the implementation of
pty.fork()
to useos.login_tty()
.A
DeprecationWarning
is now raised bypty.master_open()
andpty.slave_open()
. They were undocumented and deprecated long long ago in the docstring in favor ofpty.openpty()
.gh-101561: Add a new decorator
typing.override()
. See PEP 698 for details. Patch by Steven Troxler.gh-101360: Fix anchor matching in
pathlib.PureWindowsPath.match()
. Path and pattern anchors are now matched withfnmatch
, just like other path parts. This allows patterns such as"*:/Users/*"
to be matched.gh-101277: Remove global state from
itertools
module (PEP 687). Patches by Erlend E. Aasland.gh-100809: Fix handling of drive-relative paths (like “C:” and “C:foo”) in
pathlib.Path.absolute()
. This method now uses the OS API to retrieve the correct current working directory for the drive.gh-99138: Apply PEP 687 to
zoneinfo
. Patch by Erlend E. Aasland.gh-96764:
asyncio.wait_for()
now usesasyncio.timeout()
as its underlying implementation. Patch by Kumar Aditya.gh-88233: Correctly preserve «extra» fields in
zipfile
regardless of their ordering relative to a zip64 «extra.»bpo-23224: Fix segfaults when creating
lzma.LZMADecompressor
andbz2.BZ2Decompressor
objects without calling__init__()
, and fix leakage of locks and internal buffers when calling the__init__()
methods oflzma.LZMADecompressor
,lzma.LZMACompressor
,bz2.BZ2Compressor
, andbz2.BZ2Decompressor
objects multiple times.
Documentation¶
gh-85417: Update
cmath
documentation to clarify behaviour on branch cuts.gh-97725: Fix
asyncio.Task.print_stack()
description forfile=None
. Patch by Oleg Iarygin.
Tests¶
gh-102019: Fix deadlock on shutdown if
test_current_{exception,frames}
fails. Patch by Jacob Bower.gh-85984: Utilize new «winsize» functions from termios in pty tests.
gh-89792:
test_tools
now copies up to 10x less source data to a temporary directory during thefreeze
test by ignoring git metadata and other artifacts. It also limits its python build parallelism based on os.cpu_count instead of hard coding it as 8 cores.
Build¶
gh-99942: On Android, in a static build, python-config in embed mode no longer incorrectly reports a library to link to.
gh-99942: On Android, python.pc now correctly reports the library to link to, the same as python-config.sh.
gh-100221: Fix creating install directories in
make sharedinstall
if they exist outsideDESTDIR
already.gh-96821: Explicitly mark C extension modules that need defined signed integer overflow, and add a configure option
--with-strict-overflow
. Patch by Matthias Görgens and Shantanu Jain.
Windows¶
gh-102344: Implement
winreg.QueryValue
usingQueryValueEx
andwinreg.SetValue
usingSetValueEx
. Patch by Max Bachmann.gh-101881: Handle read and write operations on non-blocking pipes properly on Windows.
gh-101881: Add support for the os.get_blocking() and os.set_blocking() functions on Windows.
gh-101849: Ensures installer will correctly upgrade existing
py.exe
launcher installs.gh-101763: Updates copy of libffi bundled with Windows installs to 3.4.4.
gh-101759: Update Windows installer to SQLite 3.40.1.
gh-101614: Correctly handle extensions built against debug binaries that reference
python3_d.dll
.gh-101196: The functions
os.path.isdir
,os.path.isfile
,os.path.islink
andos.path.exists
are now 13% to 28% faster on Windows, by making fewer Win32 API calls.
macOS¶
gh-101759: Update macOS installer to SQLite 3.40.1.
C API¶
gh-101907: Removes use of non-standard C++ extension in public header files.
gh-99293: Document that the Py_TPFLAGS_VALID_VERSION_TAG is an internal feature, should not be used, and will be removed.
gh-101578: Add
PyErr_GetRaisedException()
andPyErr_SetRaisedException()
for saving and restoring the current exception. These functions return and accept a single exception object, rather than the triple arguments of the now-deprecatedPyErr_Fetch()
andPyErr_Restore()
. This is less error prone and a bit more efficient.Add
PyException_GetArgs()
andPyException_SetArgs()
as convenience functions for retrieving and modifying theargs
passed to the exception’s constructor.gh-91744: Introduced the Unstable C API tier, marking APi that is allowed to change in minor releases without a deprecation period. See PEP 689 for details.
Python 3.12.0 alpha 5¶
Release date: 2023-02-07
Security¶
Core and Builtins¶
gh-92173: Fix the
defs
andkwdefs
arguments toPyEval_EvalCodeEx()
and a reference leak in that function.gh-59956: The GILState API is now partially compatible with subinterpreters. Previously,
PyThreadState_GET()
andPyGILState_GetThisThreadState()
would get out of sync, causing inconsistent behavior and crashes.gh-101400: Fix wrong lineno in exception message on
continue
orbreak
which are not in a loop. Patch by Dong-hee Na.gh-101372: Fix
is_normalized()
to properly handle the UCD 3.2.0 cases. Patch by Dong-hee Na.gh-101266: Fix
sys.getsizeof()
reporting forint
subclasses.gh-101291: Refactor the
PyLongObject
struct into a normal Python object header and aPyLongValue
struct.gh-101046: Fix a possible memory leak in the parser when raising
MemoryError
. Patch by Pablo Galindogh-101037: Fix potential memory underallocation issue for instances of
int
subclasses with value zero.gh-100762: Record the (virtual) exception block depth in the oparg of
YIELD_VALUE
. Use this to avoid the expensivethrow()
when closing generators (and coroutines) that can be closed trivially.gh-100982: Adds a new
COMPARE_AND_BRANCH
instruction. This is a bit more efficient when performing a comparison immediately followed by a branch, and restores the design intent of PEP 659 that specializations are local to a single instruction.gh-100942: Fixed segfault in property.getter/setter/deleter that occurred when a property subclass overrode the
__new__
method to return a non-property instance.gh-100923: Remove the
mask
cache entry for theCOMPARE_OP
instruction and embed the mask into the oparg.gh-100892: Fix race while iterating over thread states in clearing
threading.local
. Patch by Kumar Aditya.gh-91351: Fix a case where re-entrant imports could corrupt the import deadlock detection code and cause a
KeyError
to be raised out ofimportlib/_bootstrap
. In addition to the straightforward cases, this could also happen when garbage collection leads to a warning being emitted – as happens when it collects an open socket or file)gh-100726: Optimize construction of
range
object for medium size integers.gh-100712: Added option to build cpython with specialization disabled, by setting
ENABLE_SPECIALIZATION=False
inopcode
, followed bymake regen-all
.bpo-32780: Inter-field padding is now inserted into the PEP3118 format strings obtained from
ctypes.Structure
objects, reflecting their true representation in memory.
Library¶
gh-101541: [Enum] - fix psuedo-flag creation
gh-101570: Upgrade pip wheel bundled with ensurepip (pip 23.0)
gh-101323: Fix a bug where errors where not thrown by zlib._ZlibDecompressor if encountered during decompressing.
gh-101317: Add ssl_shutdown_timeout parameter for
asyncio.StreamWriter.start_tls()
.gh-101326: Fix regression when passing
None
as second or third argument toFutureIter.throw
.gh-92123: Adapt the
_elementtree
extension module to multi-phase init (PEP 489). Patches by Erlend E. Aasland.gh-100795: Avoid potential unexpected
freeaddrinfo
call (double free) insocket
when when a libcgetaddrinfo()
implementation leaves garbage in an output pointer when returning an error. Original patch by Sergey G. Brester.gh-101143: Remove unused references to
TimerHandle
inasyncio.base_events.BaseEventLoop._add_callback
.gh-101144: Make
zipfile.Path.open()
andzipfile.Path.read_text()
also acceptencoding
as a positional argument. This was the behavior in Python 3.9 and earlier. 3.10 introduced a regression where supplying it as a positional argument would lead to aTypeError
.gh-94518: Group-related variables of
_posixsubprocess
module are renamed to stress that supplimentary group affinity is added to a fork, not replace the inherited ones. Patch by Oleg Iarygin.gh-101015: Fix
typing.get_type_hints()
on'*tuple[...]'
and*tuple[...]
. It must not drop theUnpack
part.gh-101000: Add
os.path.splitroot()
, which splits a path into a 3-item tuple(drive, root, tail)
. This new function is used bypathlib
to improve the performance of path construction by up to a third.gh-100573: Fix a Windows
asyncio
bug with named pipes where a client doingos.stat()
on the pipe would cause an error in the server that disabled serving future requests.gh-39615:
warnings.warn()
now has the ability to skip stack frames based on code filename prefix rather than only a numericstacklevel
via the newskip_file_prefixes
keyword argument.gh-100750: pass encoding kwarg to subprocess in platform
gh-100160: Emit a deprecation warning in
asyncio.DefaultEventLoopPolicy.get_event_loop()
if there is no current event loop set and it decides to create one.gh-96290: Fix handling of partial and invalid UNC drives in
ntpath.splitdrive()
, and inntpath.normpath()
on non-Windows systems. Paths such as “\server” and “\” are now considered bysplitdrive()
to contain only a drive, and consequently are not modified bynormpath()
on non-Windows systems. The behaviour ofnormpath()
on Windows systems is unaffected, as native OS APIs are used. Patch by Eryk Sun, with contributions by Barney Gale.gh-99952: Fix a reference undercounting issue in
ctypes.Structure
withfrom_param()
results larger than a C pointer.gh-67790: Add float-style formatting support for
fractions.Fraction
instances.gh-86682: Ensure runtime-created collections have the correct module name using the newly added (internal)
sys._getframemodulename()
.gh-88597:
uuid
now has a command line interface. Trypython -m uuid -h
.gh-60580:
ctypes.wintypes.BYTE
definition changed fromc_byte
toc_ubyte
to match Windows SDK. Patch by Anatoly Techtonik and Oleg Iarygin.gh-94518:
_posixsubprocess
now initializes all UID and GID variables using a reserved-1
value instead of a separate flag. Patch by Oleg Iarygin.bpo-38941: The
xml.etree.ElementTree
module now emitsDeprecationWarning
when testing the truth value of anxml.etree.ElementTree.Element
. Before, the Python implementation emittedFutureWarning
, and the C implementation emitted nothing.bpo-40077: Convert
elementtree
types to heap types. Patch by Erlend E. Aasland.bpo-29847: Fix a bug where
pathlib.Path
accepted and ignored keyword arguments. Patch provided by Yurii Karabas.gh-77772:
ctypes.CDLL
,ctypes.OleDLL
,ctypes.WinDLL
, andctypes.PyDLL
now accept path-like objects as theirname
argument. Patch by Robert Hoelzl.
Documentation¶
gh-88324: Reword
subprocess
to emphasize default behavior of stdin, stdout, and stderr arguments. Remove inaccurate statement about child file handle inheritance.
Tests¶
gh-101334:
test_tarfile
has been updated to pass when run as a high UID.
Build¶
gh-101282: Update BOLT configration not to use depreacted usage of
--split functions
. Patch by Dong-hee Na.gh-101522: Allow overriding Windows dependencies versions and paths using MSBuild properties.
gh-77532: Minor fixes to allow building with
PlatformToolset=ClangCL
on Windows.gh-101152: In accordance with PEP 699, the
ma_version_tag
field inPyDictObject
is deprecated for extension modules. Accessing this field will generate a compiler warning at compile time. This field will be removed in Python 3.14.gh-100340: Allows -Wno-int-conversion for wasm-sdk 17 and onwards, thus enables building WASI builds once against the latest sdk.
gh-101060: Conditionally add
-fno-reorder-blocks-and-partition
in configure. Effectively fixes--enable-bolt
when using Clang, as this appears to be a GCC-only flag.gh-98705:
__bool__
is defined in AIX system header files which breaks the build in AIX, so undefine it.gh-98636: Fix a regression in detecting
gdbm_compat
library for the_gdbm
module build.gh-96305:
_aix_support
now uses a simple code to get platform details rather than the now non-existent_bootsubprocess
during bootstrap.
Windows¶
gh-101543: Ensure the install path in the registry is only used when the standard library hasn’t been located in any other way.
gh-101467: The
py.exe
launcher now correctly filters when only a single runtime is installed. It also correctly handles prefix matches on tags so that-3.1
does not match3.11
, but would still match3.1-32
.gh-99834: Updates bundled copy of Tcl/Tk to 8.6.13.0
gh-101135: Restore ability to launch older 32-bit versions from the
py.exe
launcher when both 32-bit and 64-bit installs of the same version are available.gh-82052: Fixed an issue where writing more than 32K of Unicode output to the console screen in one go can result in mojibake.
gh-100320: Ensures the
PythonPath
registry key from an install is used when launching from a different copy of Python that relies on an existing install to provide a copy of its modules and standard library.gh-100247: Restores support for the
py.exe
launcher finding shebang commands in its configuration file using the full command name.
Python 3.12.0 alpha 4¶
Release date: 2023-01-10
Core and Builtins¶
gh-100776: Fix misleading default value in
input()
”s__text_signature__
.gh-99005: Remove
UNARY_POSITIVE
,ASYNC_GEN_WRAP
andLIST_TO_TUPLE
, replacing them with intrinsics.gh-99005: Add new
CALL_INSTRINSIC_1
instruction. RemoveIMPORT_STAR
,PRINT_EXPR
andSTOPITERATION_ERROR
, replacing them with theCALL_INSTRINSIC_1
instruction.gh-100288: Remove the LOAD_ATTR_METHOD_WITH_DICT specialized instruction. Stats show it is not useful.
gh-100720: Added
_PyFrame_NumSlotsForCodeObject
, which returns the number of slots needed in a frame for a given code object.gh-100719: Removed the co_nplaincellvars field from the code object, as it is redundant.
gh-100637: Fix
int.__sizeof__()
calculation to include the 1 element ob_digit array for 0 and False.gh-100649: Update the native_thread_id field of PyThreadState after fork.
gh-100126: Fix an issue where «incomplete» frames could be briefly visible to C code while other frames are being torn down, possibly resulting in corruption or hard crashes of the interpreter while running finalizers.
gh-87447: Fix
SyntaxError
on comprehension rebind checking with names that are not actually redefined.Now reassigning
b
in[(b := 1) for a, b.prop in some_iter]
is allowed. Reassigninga
is still disallowed as per PEP 572.gh-100268: Add
int.is_integer()
to improve duck type compatibility betweenint
andfloat
.gh-100425: Improve the accuracy of
sum()
with compensated summation.gh-100374: Fix incorrect result and delay in
socket.getfqdn()
. Patch by Dominic Socular.gh-100357: Convert
vars
,dir
,next
,getattr
, anditer
to argument clinic.gh-100117: Improve the output of
co_lines
by emitting only one entry for each line range.gh-90043: Handle NaNs when specializing
COMPARE_OP
forfloat
values.gh-100222: Redefine the
_Py_CODEUNIT
typedef as a union to describe its layout to the C compiler, avoiding type punning and improving clarity.gh-99955: Internal compiler functions (in compile.c) now consistently return -1 on error and 0 on success.
gh-100188: The
BINARY_SUBSCR_LIST_INT
andBINARY_SUBSCR_TUPLE_INT
instructions are no longer used for negative integers because those instructions always miss when encountering negative integers.gh-99110: Initialize frame->previous in frameobject.c to fix a segmentation fault when accessing frames created by
PyFrame_New()
.gh-94155: Improved the hashing algorithm for code objects, mitigating some hash collisions.
gh-99540:
None
now hashes to a constant value. This is not a requirements change.gh-100143: When built with
--enable-pystats
, stats collection is now off by default. To enable it early at startup, pass the-Xpystats
flag. Stats are now always dumped, even if switched off.gh-100146: Improve
BUILD_LIST
opcode so that it works similarly to theBUILD_TUPLE
opcode, by stealing references from the stack rather than repeatedly using stack operations to set list elements. Implementation details are in a new private API_PyList_FromArraySteal()
.gh-100110: Specialize
FOR_ITER
for tuples.gh-100050: Honor existing errors obtained when searching for mismatching parentheses in the tokenizer. Patch by Pablo Galindo
gh-92216: Improve the performance of
hasattr()
for type objects with a missing attribute.gh-99554: Pack debugging location tables more efficiently during bytecode compilation.
gh-98522: Add an internal version number to code objects, to give better versioning of inner functions and comprehensions, and thus better specialization of those functions. This change is invisible to both Python and C extensions.
gh-94603: Improve performance of
list.pop
for small lists.bpo-32782:
ctypes
arrays of length 0 now report a correct itemsize when amemoryview
is constructed from them, rather than always giving a value of 0.
Library¶
gh-100833: Speed up
math.fsum()
by removing defensivevolatile
qualifiers.gh-100805: Modify
random.choice()
implementation to once again work with NumPy arrays.gh-100813: Add
socket.IP_PKTINFO
constant.gh-100792: Make
email.message.Message.__contains__()
twice as fast.gh-91851: Microoptimizations for
fractions.Fraction.__round__()
,fractions.Fraction.__ceil__()
andfractions.Fraction.__floor__()
.gh-90104: Avoid RecursionError on
repr
if a dataclass field definition has a cyclic reference.gh-100689: Fix crash in
pyexpat
by statically allocatingPyExpat_CAPI
capsule.gh-100740: Fix
unittest.mock.Mock
not respecting the spec for attribute names prefixed withassert
.gh-91219: Change
SimpleHTTPRequestHandler
to support subclassing to provide a different set of index file names instead of using__init__
parameters.gh-100690:
Mock
objects which are not unsafe will now raise anAttributeError
when accessing an attribute that matches the name of an assertion but without the prefixassert_
, e.g. accessingcalled_once
instead ofassert_called_once
. This is in addition to this already happening for accessing attributes with prefixesassert
,assret
,asert
,aseert
, andassrt
.gh-89727: Simplify and optimize
os.walk()
by usingisinstance()
checks to check the top of the stack.gh-100485: Add math.sumprod() to compute the sum of products.
gh-86508: Fix
asyncio.open_connection()
to skip binding to local addresses of different family. Patch by Kumar Aditya.gh-97930:
importlib.resources.files
now accepts a module as an anchor instead of only accepting packages. If a module is passed, resources are resolved adjacent to that module (in the same package or at the package root). The parameter was renamed frompackage
toanchor
with a compatibility shim for those passing by keyword. Additionally, the newanchor
parameter is now optional and will default to the caller’s module.gh-100585: Fixed a bug where importlib.resources.as_file was leaving file pointers open
gh-100562: Improve performance of
pathlib.Path.absolute()
by nearly 2x. This comes at the cost of a performance regression inpathlib.Path.cwd()
, which is generally used less frequently in user code.gh-100519: Small simplification of
http.cookiejar.eff_request_host()
that improves readability and better matches the RFC wording.gh-100287: Fix the interaction of
unittest.mock.seal()
withunittest.mock.AsyncMock
.gh-100488: Add
Fraction.is_integer()
to check whether afractions.Fraction
is an integer. This improves duck type compatibility withfloat
andint
.gh-100474:
http.server
now checks that an index page is actually a regular file before trying to serve it. This avoids issues with directories namedindex.html
.gh-100363: Speed up
asyncio.get_running_loop()
by removing redundantgetpid
checks. Patch by Kumar Aditya.gh-78878: Fix crash when creating an instance of
_ctypes.CField
.gh-100348: Fix ref cycle in
asyncio._SelectorSocketTransport
by removing_read_ready_cb
inclose
.gh-100344: Provide C implementation for
asyncio.current_task()
for a 4x-6x speedup.gh-100272: Fix JSON serialization of OrderedDict. It now preserves the order of keys.
gh-83076: Instantiation of
Mock()
andAsyncMock()
is now 3.8x faster.gh-100234: Set a default value of 1.0 for the
lambd
parameter in random.expovariate().gh-100228: A
DeprecationWarning
may be raised whenos.fork()
oros.forkpty()
is called from multi-threaded processes. Forking with threads is unsafe and can cause deadlocks, crashes and subtle problems. Lack of a warning does not indicate that the fork call was actually safe, as Python may not be aware of all threads.gh-100039: Improve signatures for enums and flags.
gh-100133: Fix regression in
asyncio
where a subprocess would sometimes lose data received from pipe.bpo-44592: Fixes inconsistent handling of case sensitivity of extrasaction arg in
csv.DictWriter
.gh-100098: Fix
tuple
subclasses being cast totuple
when used as enum values.gh-85432: Rename the fmt parameter of the pure-Python implementation of
datetime.time.strftime()
to format. Rename the t parameter ofdatetime.datetime.fromtimestamp()
to timestamp. These changes mean the parameter names in the pure-Python implementation now match the parameter names in the C implementation. Patch by Alex Waygood.gh-98778: Update
HTTPError
to be initialized properly, even if thefp
isNone
. Patch by Dong-hee Na.gh-99925: Unify error messages in JSON serialization between
json.dumps(float('nan'), allow_nan=False)
andjson.dumps(float('nan'), allow_nan=False, indent=<SOMETHING>)
. Now both include the representation of the value that could not be serialized.gh-89727: Fix issue with
os.walk()
where aRecursionError
would occur on deep directory structures by adjusting the implementation ofos.walk()
to be iterative instead of recursive.gh-94943: Add Dataclass support to the
Enum
__repr__()
. When inheriting from adataclass
, only show the field names in the value section of the memberrepr()
, and not the dataclass” class name.gh-83035: Fix
inspect.getsource()
handling of decorator calls with nested parentheses.gh-99576: Fix
.save()
method forLWPCookieJar
andMozillaCookieJar
: saved file was not truncated on repeated save.gh-94912: Add
inspect.markcoroutinefunction()
decorator which manually marks a function as a coroutine for the benefit ofiscoroutinefunction()
.gh-99509: Add PEP 585 support for
multiprocessing.queues.Queue
.gh-99482: Remove
Jython
partial compatibility code from several stdlib modules.gh-99433: Fix
doctest
failure ontypes.MethodWrapperType
in modules.gh-85267: Several improvements to
inspect.signature()
”s handling of__text_signature
. - Fixes a case whereinspect.signature()
dropped parameters - Fixes a case whereinspect.signature()
raisedtokenize.TokenError
- Allowsinspect.signature()
to understand defaults involving binary operations of constants -inspect.signature()
is documented as only raisingTypeError
orValueError
, but sometimes raisedRuntimeError
. These cases now raiseValueError
- Removed a dead code pathgh-91166:
asyncio
is optimized to avoid excessive copying when writing to socket and usesendmsg()
if the platform supports it. Patch by Kumar Aditya.gh-98030: Add missing TCP socket options from Linux:
TCP_MD5SIG
,TCP_THIN_LINEAR_TIMEOUTS
,TCP_THIN_DUPACK
,TCP_REPAIR
,TCP_REPAIR_QUEUE
,TCP_QUEUE_SEQ
,TCP_REPAIR_OPTIONS
,TCP_TIMESTAMP
,TCP_CC_INFO
,TCP_SAVE_SYN
,TCP_SAVED_SYN
,TCP_REPAIR_WINDOW
,TCP_FASTOPEN_CONNECT
,TCP_ULP
,TCP_MD5SIG_EXT
,TCP_FASTOPEN_KEY
,TCP_FASTOPEN_NO_COOKIE
,TCP_ZEROCOPY_RECEIVE
,TCP_INQ
,TCP_TX_DELAY
.gh-88500: Reduced the memory usage of
urllib.parse.unquote()
andurllib.parse.unquote_to_bytes()
on large values.gh-96127:
inspect.signature
was raisingTypeError
on call with mock objects. Now it correctly returns(*args, **kwargs)
as infered signature.gh-95882: Fix a 3.11 regression in
asynccontextmanager()
, which caused it to propagate exceptions with incorrect tracebacks and fix a 3.11 regression incontextmanager()
, which caused it to propagate exceptions with incorrect tracebacks forStopIteration
.gh-78707: Deprecate passing more than one positional argument to
pathlib.PurePath.relative_to()
andis_relative_to()
.gh-92122: Fix reStructuredText syntax errors in docstrings in the
enum
module.gh-91851: Optimize the
Fraction
arithmetics for small components.bpo-24132: Make
pathlib.PurePath
andPath
subclassable (private to start). Previously, attempting to instantiate a subclass resulted in anAttributeError
being raised. Patch by Barney Gale.bpo-40447: Accept
os.PathLike
(such aspathlib.Path
) in thestripdir
arguments ofcompileall.compile_file()
andcompileall.compile_dir()
.bpo-36880: Fix a reference counting issue when a
ctypes
callback with return typepy_object
returnsNone
, which could cause crashes.
Documentation¶
gh-100616: Document existing
attr
parameter tocurses.window.vline()
function incurses
.gh-100472: Remove claim in documentation that the
stripdir
,prependdir
andlimit_sl_dest
parameters ofcompileall.compile_dir()
andcompileall.compile_file()
could bebytes
.bpo-25377: Clarify use of octal format of mode argument in help(os.chmod) as well as help(os.fchmod)
Tests¶
gh-100454: Start running SSL tests with OpenSSL 3.1.0-beta1.
gh-100086: The Python test runner (libregrtest) now logs Python build information like «debug» vs «release» build, or LTO and PGO optimizations. Patch by Victor Stinner.
gh-93018: Make two tests forgiving towards host system libexpat with backported security fixes applied.
Build¶
gh-100540: Removed the
--with-system-ffi
configure
option;libffi
must now always be supplied by the system on all non-Windows platforms. The option has had no effect on non-Darwin platforms for several releases, and in 3.11 only had the non-obvious effect of invokingpkg-config
to findlibffi
and never setting-DUSING_APPLE_OS_LIBFFI
. Now on Darwin platformsconfigure
will first check for the OSlibffi
and then fall back to the same processing as other platforms if it is not found.gh-88267: Avoid exporting Python symbols in linked Windows applications when the core is built as static.
bpo-41916: Allow override of ac_cv_cxx_thread so that cross compiled python can set -pthread for CXX.
Windows¶
gh-100180: Update Windows installer to OpenSSL 1.1.1s
gh-99191: Use
_MSVC_LANG >= 202002L
instead of less-precise_MSC_VER >=1929
to more accurately test for C++20 support inPC/_wmimodule.cpp
.gh-79218: Define
MS_WIN64
for Mingw-w64 64bit, fix cython compilation failure.gh-99941: Ensure that
asyncio.Protocol.data_received()
receives an immutablebytes
object (as documented), instead ofbytearray
.bpo-43984:
winreg.SetValueEx()
now leaves the target value untouched in the case of conversion errors. Previously,-1
would be written in case of such errors.bpo-34816:
hasattr(ctypes.windll, 'nonexistant')
now returnsFalse
instead of raisingOSError
.
macOS¶
Tools/Demos¶
bpo-45256: Fix a bug that caused an
AttributeError
to be raised inpython-gdb.py
whenpy-locals
is used without a frame.gh-100342: Add missing
NULL
check for possible allocation failure in*args
parsing in Argument Clinic.
C API¶
gh-99947: Raising SystemError on import will now have its cause be set to the original unexpected exception.
gh-99240: In argument parsing, after deallocating newly allocated memory, reset its pointer to NULL.
gh-98724: The
Py_CLEAR
,Py_SETREF
andPy_XSETREF
macros now only evaluate their arguments once. If an argument has side effects, these side effects are no longer duplicated. Patch by Victor Stinner.
Python 3.12.0 alpha 3¶
Release date: 2022-12-06
Security¶
gh-100001:
python -m http.server
no longer allows terminal control characters sent within a garbage request to be printed to the stderr server log.This is done by changing the
http.server
BaseHTTPRequestHandler
.log_message
method to replace control characters with a\xHH
hex escape before printing.gh-87604: Avoid publishing list of active per-interpreter audit hooks via the
gc
module
Core and Builtins¶
gh-99891: Fix a bug in the tokenizer that could cause infinite recursion when showing syntax warnings that happen in the first line of the source. Patch by Pablo Galindo
gh-91054: Add
PyCode_AddWatcher()
andPyCode_ClearWatcher()
APIs to register callbacks to receive notification on creation and destruction of code objects.gh-99729: Fix an issue that could cause frames to be visible to Python code as they are being torn down, possibly leading to memory corruption or hard crashes of the interpreter.
gh-99708: Fix bug where compiler crashes on an if expression with an empty body block.
gh-99578: Fix a reference bug in
_imp.create_builtin()
after the creation of the first sub-interpreter for modulesbuiltins
andsys
. Patch by Victor Stinner.gh-99581: Fixed a bug that was causing a buffer overflow if the tokenizer copies a line missing the newline caracter from a file that is as long as the available tokenizer buffer. Patch by Pablo galindo
gh-99553: Fix bug where an
ExceptionGroup
subclass can wrap aBaseException
.gh-99547: Add a function to os.path to check if a path is a junction: isjunction. Add similar functionality to pathlib.Path as is_junction.
gh-99370: Fix zip path for venv created from a non-installed python on POSIX platforms.
gh-99377: Add audit events for thread creation and clear operations.
gh-98686: Remove the
BINARY_OP_GENERIC
andCOMPARE_OP_GENERIC
«specializations».gh-99298: Remove the remaining error paths for attribute specializations, and refuse to specialize attribute accesses on types that haven’t had
PyType_Ready()
called on them yet.gh-99127: Allow some features of
syslog
to the main interpreter only. Patch by Dong-hee Na.gh-91053: Optimizing interpreters and JIT compilers may need to invalidate internal metadata when functions are modified. This change adds the ability to provide a callback that will be invoked each time a function is created, modified, or destroyed.
gh-90994: Improve error messages when there’s a syntax error with call arguments. The following three cases are covered: - No value is assigned to a named argument, eg
foo(a=)
. - A value is assigned to a star argument, egfoo(*args=[0])
. - A value is assigned to a double-star keyword argument, egfoo(**kwarg={'a': 0})
.bpo-45026: Optimize the
range
object iterator. It is now smaller, faster iteration of ranges containing large numbers. Smaller pickles, faster unpickling.bpo-31718: Raise
ValueError
instead ofSystemError
when methods of uninitializedio.IncrementalNewlineDecoder
objects are called. Patch by Oren Milman.bpo-38031: Fix a possible assertion failure in
io.FileIO
when the opener returns an invalid file descriptor.
Library¶
gh-100001: Also escape s in the http.server BaseHTTPRequestHandler.log_message so that it is technically possible to parse the line and reconstruct what the original data was. Without this a xHH is ambiguious as to if it is a hex replacement we put in or the characters r»x» came through in the original request line.
gh-99957: Add
frozen_default
parameter totyping.dataclass_transform()
.gh-79033: Fix
asyncio.Server.wait_closed()
to actually do what the docs promise – wait for all existing connections to complete, after closing the server.gh-51524: Fix bug when calling trace.CoverageResults with valid infile.
gh-99645: Fix a bug in handling class cleanups in
unittest.TestCase
. NowaddClassCleanup()
uses separate lists for differentTestCase
subclasses, anddoClassCleanups()
only cleans up the particular class.gh-99508: Fix
TypeError
inLib/importlib/_bootstrap_external.py
while calling_imp.source_hash()
.gh-66285: Fix
asyncio
to not share event loop and signal wakeupfd in forked processes. Patch by Kumar Aditya.gh-97001: Release the GIL when calling termios APIs to avoid blocking threads.
gh-92647: Use final status of an enum to determine lookup or creation branch of functional API.
gh-99388: Add loop_factory parameter to
asyncio.run()
to allow specifying a custom event loop factory. Patch by Kumar Aditya.gh-99341: Fix
ast.increment_lineno()
to also coverast.TypeIgnore
when changing line numbers.gh-99382: Check the number of arguments in substitution in user generics containing a
TypeVarTuple
and one or moreTypeVar
.gh-99379: Fix substitution of
ParamSpec
followed byTypeVarTuple
in generic aliases.gh-99344: Fix substitution of
TypeVarTuple
andParamSpec
together in user generics.gh-99284: Remove
_use_broken_old_ctypes_structure_semantics_
old untested and undocumented hack fromctypes
.gh-99201: Fix
IndexError
when initializing the config variables on Windows ifHAVE_DYNAMIC_LOADING
is not set.gh-99240: Fix double-free bug in Argument Clinic
str_converter
by extracting memory clean up to a newpost_parsing
section.gh-64490: Fix refcount error when arguments are packed to tuple in Argument Clinic.
gh-99029:
pathlib.PurePath.relative_to()
now treats naked Windows drive paths as relative. This brings its behaviour in line with other parts of pathlib.gh-98253: The implementation of the typing module is now more resilient to reference leaks in binary extension modules.
Previously, a reference leak in a typed C API-based extension module could leak internals of the typing module, which could in turn introduce leaks in essentially any other package with typed function signatures. Although the typing package is not the original source of the problem, such non-local dependences exacerbate debugging of large-scale projects, and the implementation was therefore changed to reduce harm by providing better isolation.
gh-98458: Fix infinite loop in unittest when a self-referencing chained exception is raised
gh-93453:
asyncio.get_event_loop()
and many otherasyncio
functions likeasyncio.ensure_future()
,asyncio.shield()
orasyncio.gather()
, and also theget_event_loop()
method ofasyncio.BaseDefaultEventLoopPolicy
now raise aRuntimeError
if called when there is no running event loop and the current event loop was not set. Previously they implicitly created and set a new current event loop.DeprecationWarning
is no longer emitted if there is no running event loop but the current event loop was set.gh-97966: On
uname_result
, restored expectation that_fields
and_asdict
would include all six properties includingprocessor
.gh-98248: Provide informative error messages in
struct.pack()
when its integral arguments are not in range.gh-98108:
zipfile.Path
is now pickleable if its initialization parameters were pickleable (e.g. for file system paths).gh-98098: Created packages from zipfile and test_zipfile modules, separating
zipfile.Path
functionality.gh-82836: Fix
is_private
properties in theipaddress
module. Previously non-private networks (0.0.0.0/0) would return True from this method; now they correctly return False.gh-96828: Add an
OP_ENABLE_KTLS
option for enabling the use of the kernel TLS (kTLS). Patch by Illia Volochii.gh-88863: To avoid apparent memory leaks when
asyncio.open_connection()
raises, break reference cycles generated by local exception and future instances (which has exception instance as its member var). Patch by Dong Uk, Kang.gh-91078:
TarFile.next()
now returnsNone
when called on an empty tarfile.bpo-47220: Document the optional callback parameter of
WeakMethod
. Patch by Géry Ogam.bpo-44817: Ignore WinError 53 (ERROR_BAD_NETPATH), 65 (ERROR_NETWORK_ACCESS_DENIED) and 161 (ERROR_BAD_PATHNAME) when using ntpath.realpath().
bpo-41260: Rename the fmt parameter of the pure Python implementation of
datetime.date.strftime()
to format.bpo-15999: All built-in functions now accept arguments of any type instead of just
bool
andint
for boolean parameters.
Documentation¶
gh-99931: Use sphinxext-opengraph to generate OpenGraph metadata.
gh-89682: Reworded docstring of the default
__contains__
to clarify that it returns abool
.gh-88330: Improved the description of what a resource is in importlib.resources docs.
gh-92892: Document that calling variadic functions with ctypes requires special care on macOS/arm64 (and possibly other platforms).
bpo-41825: Restructured the documentation for the
os.wait*
family of functions, and improved the docs foros.waitid()
with more explanation of the possible argument constants.
Tests¶
gh-99892: Skip test_normalization() of test_unicodedata if it fails to download NormalizationTest.txt file from pythontest.net. Patch by Victor Stinner.
gh-99934: Correct test_marsh on (32 bit) x86: test_deterministic sets was failing.
gh-99741: We’ve implemented multi-phase init (PEP 489/630/687) for the internal (for testing) _xxsubinterpreters module.
gh-99659: Optional big memory tests in
test_sqlite3
now catch the correctsqlite.DataError
exception type in case of too large strings and/or blobs passed.gh-99593: Cover the Unicode C API with tests.
gh-96002: Add functional test for Argument Clinic.
Build¶
gh-99086: Fix
-Wimplicit-int
,-Wstrict-prototypes
, and-Wimplicit-function-declaration
compiler warnings in configure checks.gh-99337: Fix a compilation issue with GCC 12 on macOS.
gh-99289: Add a
COMPILEALL_OPTS
variable in Makefile to overridecompileall
options (default:-j0
) inmake install
. Also merged thecompileall
commands into a single command building .pyc files for the all optimization levels (0, 1, 2) at once. Patch by Victor Stinner.gh-98872: Fix a possible fd leak in
Programs/_freeze_module.c
introduced in Python 3.11.gh-88226: Always define
TARGET_*
labels inPython/ceval.c
, even ifUSE_COMPUTED_GOTOS
is disabled. This allows breakpoints to be set at those labels in (for instance)gdb
.
Windows¶
gh-99345: Use faster initialization functions to detect install location for Windows Store package
gh-98629: Fix initialization of
sys.version
andsys._git
on Windowsgh-99442: Fix handling in Lanzador de Python para Windows when
argv[0]
does not include a file extension.bpo-40882: Fix a memory leak in
multiprocessing.shared_memory.SharedMemory
on Windows.
macOS¶
Tools/Demos¶
gh-64490: Argument Clinic varargs bugfixes
Fix out-of-bounds error in
_PyArg_UnpackKeywordsWithVararg()
.Fix incorrect check which allowed more than one varargs in clinic.py.
Fix miscalculation of
noptargs
in generated code.Do not generate
noptargs
when there is a vararg argument and no optional argument.
C API¶
gh-98680:
PyBUF_*
constants were marked as part of Limited API of Python 3.11+. These were available in 3.11.0 withPy_LIMITED_API
defined for 3.11, and are necessary to use the buffer API.gh-99612: Fix
PyUnicode_DecodeUTF8Stateful()
for ASCII-only data:*consumed
was not set.gh-47146: The
structmember.h
header is deprecated. Its non-deprecated contents are now available just by includingPython.h
, with aPy_
prefix added if it was missing. (Deprecated contents areT_OBJECT
,T_NONE
, and no-op flags.) Patch by Petr Viktorin, based on earlier work by Alexander Belopolsky and Matthias Braun.
Python 3.12.0 alpha 2¶
Release date: 2022-11-14
Security¶
gh-98433: The IDNA codec decoder used on DNS hostnames by
socket
orasyncio
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 asurllib
http3xx
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.
gh-98739: Update bundled libexpat to 2.5.0
Core and Builtins¶
gh-81057: The docs clearly say that
PyImport_Inittab
,PyImport_AppendInittab()
, andPyImport_ExtendInittab()
should not be used afterPy_Initialize()
has been called. We now enforce this for the two functions. Additionally, the runtime now uses an internal copy ofPyImport_Inittab
, to guard against modification.gh-99298: Fix an issue that could potentially cause incorrect error handling for some bytecode instructions.
gh-99254: The compiler now removes all unused constants from code objects (except the first one, which may be a docstring).
gh-99205: Fix an issue that prevented
PyThreadState
andPyInterpreterState
memory from being freed properly.gh-81057: 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.gh-99181: Fix failure in
except*
with unhashable exceptions.gh-99204: Fix calculation of
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>»).gh-96055: Update
faulthandler
to emit an error message with the proper unexpected signal number. Patch by Dong-hee Na.gh-99153: Fix location of
SyntaxError
for atry
block with bothexcept
andexcept*
.gh-98686: Merge the adaptive opcode logic into each instruction’s unquickened variant, and merge the logic in
EXTENDED_ARG_QUICK
intoEXTENDED_ARG
. With these changes, the quickening that happens at code object creation is now only responsible for initializing warmup counters and inserting superinstructions.gh-99103: Fix the error reporting positions of specialized traceback anchors when the source line contains Unicode characters.
gh-99139: Improve the error suggestion for
NameError
exceptions for instances. Now if aNameError
is raised in a method and the instance has an attribute that’s exactly equal to the name in the exception, the suggestion will includeself.<NAME>
instead of the closest match in the method scope. Patch by Pablo Galindogh-98401: Octal escapes with value larger than
0o377
(ex:"\477"
), deprecated in Python 3.11, now produce aSyntaxWarning
, instead ofDeprecationWarning
. In a future Python version they will be eventually aSyntaxError
. Patch by Victor Stinner.gh-98401: A backslash-character pair that is not a valid escape sequence now generates a
SyntaxWarning
, instead ofDeprecationWarning
. For example,re.compile("\d+\.\d+")
now emits aSyntaxWarning
("\d"
is an invalid escape sequence), use raw strings for regular expression:re.compile(r"\d+\.\d+")
. In a future Python version,SyntaxError
will eventually be raised, instead ofSyntaxWarning
. Patch by Victor Stinner.gh-96793: Handle StopIteration and StopAsyncIteration raised in generator or coroutines in the bytecode, rather than in wrapping C code.
gh-98931: Improve the
SyntaxError
error message when the user typesimport x from y
instead offrom y import x
. Patch by Pablo Galindogh-98852: Fix subscription of type aliases containing bare generic types or types like
TypeVar
: for exampletuple[A, T][int]
andtuple[TypeVar, T][int]
, whereA
is a generic type, andT
is a type variable.gh-98925: Lower the recursion depth for marshal on WASI to support (in-development) wasmtime 2.0.
gh-98783: Fix multiple crashes in debug mode when
str
subclasses are used instead ofstr
itself.gh-98811: 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.gh-96793: Add specialization of
FOR_ITER
for generators. Saves multiple layers of dispatch and checking to get from theFOR_ITER
instruction in the caller to theRESUME
in the generator.gh-98586: Added the methods
PyObject_Vectorcall()
andPyObject_VectorcallMethod()
to the Limited API along with the auxiliary macro constantPY_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.
gh-99257: Fix an issue where member descriptors (such as those for
__slots__
) could behave incorrectly or crash instead of raising aTypeError
when accessed via an instance of an invalid type.gh-93143: Rather than changing
co_code
, the interpreter will now display aRuntimeWarning
and assignNone
to any fast locals that are left unbound after jumps ordel
statements executed while tracing.gh-96421: When calling into Python code from C code, through
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 checkingframe->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
RETURN_VALUE
,YIELD_VALUE
, andRETURN_GENERATOR
, which now clear the frame.gh-98415: Fix detection of MAC addresses for
uuid
on certain OSs. Patch by Chaim Sandersgh-98686: Quicken all code objects, and specialize adaptive bytecode instructions more aggressively.
gh-92119: Print exception class name instead of its string representation when raising errors from
ctypes
calls.gh-91058:
ImportError
raised from failedfrom <module> import <name>
now include suggestions for the value of<name>
based on the available names in<module>
. Patch by Pablo Galindogh-96793: The
FOR_ITER
now leaves the iterator on the stack on termination of the loop. This is to assist specialization of loops for generators.gh-90716: 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.
gh-95389: Expose
ETH_P_ALL
and some of the ETHERTYPE_* constants insocket
. Patch by Noam Cohen.gh-93696: Allow
pdb
to locate source for frozen modules in the standard library.
Library¶
gh-99418: Fix bug in
urllib.parse.urlparse()
that causes URL schemes that begin with a digit, a plus sign, or a minus sign to be parsed incorrectly.gh-94597: Deprecate
asyncio.AbstractChildWatcher
to be removed in Python 3.14. Patch by Kumar Aditya.gh-99305: Improve performance of
secrets.token_hex()
.gh-74044: Fixed bug where
inspect.signature()
reported incorrect arguments for decorated methods.gh-99275: Fix
SystemError
inctypes
when exception was not set during__initsubclass__
.gh-99277: Remove older version of
_SSLProtocolTransport.get_write_buffer_limits
inasyncio.sslproto
gh-99248: fix negative numbers failing in verify()
gh-99155: Fix
statistics.NormalDist
pickle with0
and1
protocols.gh-93464:
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')
.gh-99134: Update the bundled copy of pip to version 22.3.1.
gh-92584: Remove the
distutils
package. It was deprecated in Python 3.10 by PEP 632 «Deprecate distutils module». For projects still usingdistutils
and cannot be updated to something else, thesetuptools
project can be installed: it still providesdistutils
. Patch by Victor Stinner.gh-98999: Now
_pyio
is consistent with_io
in raisingValueError
when executing methods over closed buffers.gh-83004: Clean up refleak on failed module initialisation in
_zoneinfo
gh-83004: Clean up refleaks on failed module initialisation in
_pickle
gh-83004: Clean up refleak on failed module initialisation in
_io
.gh-98897: Fix memory leak in
math.dist()
when both points don’t have the same dimension. Patch by Kumar Aditya.gh-98878: Use the frame bound builtins when offering a name suggestion in
traceback
to prevent crashing when__builtins__
is not a dict.gh-98139: In
importlib._bootstrap
, enhance namespace package repr to<module 'x' (namespace) from ['path']>
.gh-90352: Fix
_SelectorDatagramTransport
to inherit fromDatagramTransport
inasyncio
. Patch by Kumar Aditya.gh-98793: Fix argument typechecks in
_overlapped.WSAConnect()
and_overlapped.Overlapped.WSASendTo()
functions.gh-98744: Prevent crashing in
traceback
when retrieving the byte-offset for some source files that contain certain unicode characters.gh-98740: Fix internal error in the
re
module which in very rare circumstances prevented compilation of a regular expression containing a conditional expression without the «else» branch.gh-98703: Fix
asyncio.StreamWriter.drain()
to callprotocol.connection_lost
callback only once on Windows.gh-98624: Add a mutex to unittest.mock.NonCallableMock to protect concurrent access to mock attributes.
gh-98658: The
array.array
class now supports subscripting, making it a generic type.gh-98284: Improved
TypeError
message for undefined abstract methods of aabc.ABC
instance. The names of the missing methods are surrounded by single-quotes to highlight them.gh-96151: Allow
BUILTINS
to be a valid field name for frozen dataclasses.gh-98086: Make sure
patch.dict()
can be applied on async functions.gh-72719: Remove modules
asyncore
andasynchat
, which were deprecated by PEP 594.gh-96192: Fix handling of
bytes
path-like objects inos.ismount()
.gh-94172:
ftplib
: Remove theFTP_TLS.ssl_version
class attribute: use the context parameter instead. Patch by Victor Stinnergh-94172: Remove the keyfile and certfile parameters from the
ftplib
,imaplib
,poplib
andsmtplib
modules, and the key_file, cert_file and check_hostname parameters from thehttp.client
module, all deprecated since Python 3.6. Use the context parameter (ssl_context inimaplib
) instead. Patch by Victor Stinner.gh-83638: Add the
autocommit
attribute tosqlite3.Connection
and the autocommit parameter tosqlite3.connect()
to control PEP 249-compliant transaction handling. Patch by Erlend E. Aasland.gh-92452: Fixed a race condition that could cause
sysconfig.get_config_var()
to incorrectly returnNone
in multi-threaded programs.gh-91803: Fix an error when using a method of objects mocked with
unittest.mock.create_autospec()
after it was sealed withunittest.mock.seal()
function.bpo-38523:
shutil.copytree()
now applies the ignore_dangling_symlinks argument recursively.bpo-40358: Add walk_up argument in
pathlib.PurePath.relative_to()
.bpo-36267: Fix IndexError in
argparse.ArgumentParser
when astore_true
action is given an explicit argument.
Documentation¶
gh-98832: Changes wording of docstring for
pathlib.Path.iterdir()
.gh-97966: Update uname docs to clarify the special nature of the platform attribute and to indicate when it became late-bound.
Tests¶
gh-98903: The Python test suite now fails wit exit code 4 if no tests ran. It should help detecting typos in test names and test methods.
gh-98713: Fix a bug in the
typing
tests where a test relying on CPython-specific implementation details was not decorated with@cpython_only
and was not skipped on other implementations.gh-87390: Add tests for star-unpacking with PEP 646, and some other miscellaneous PEP 646 tests.
gh-96853: Added explicit coverage of
Py_Initialize
(and hencePy_InitializeEx
) back to the embedding tests (all other embedding tests migrated toPy_InitializeFromConfig
in Python 3.11)bpo-34272: Some C API tests were moved into the new Lib/test/test_capi/ directory.
Build¶
gh-99086: Fix
-Wimplicit-int
compiler warning in configure check forPTHREAD_SCOPE_SYSTEM
.gh-99016: Fix build with
PYTHON_FOR_REGEN=python3.8
.gh-97731: Specify the full path to the source location for
make docclean
(needed for cross-builds).gh-98949: Drop unused build dependency on
readelf
.gh-98989: Use
python3.11
, if available, for regeneration and freezing.gh-98831: 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 inPython/bytecodes.c
, in the form of a custom DSL (under development). The tooling reads this file and writesPython/generated_cases.c.h
, which is then included byPython/ceval.c
to provide most of the cases of the main interpreter switch.gh-98817: 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.
gh-98776: Fix
make regen-test-levenshtein
for out-of-tree builds.gh-98707: Don’t use vendored
libmpdec
headers if--with-system-libmpdec
is passed to configure. Don’t use vendoredlibexpat
headers if--with-system-expat
is passed to configure.
Windows¶
gh-98689: 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.gh-98790: Assumes that a missing
DLLs
directory means that standard extension modules are in the executable’s directory.gh-98745: Update
py.exe
launcher to install 3.11 by default and 3.12 on request.gh-98692: Fix the Lanzador de Python para Windows ignoring unrecognized shebang lines instead of treating them as local paths
gh-94328: Update Windows installer to use SQLite 3.39.4.
macOS¶
gh-94328: Update macOS installer to SQLite 3.39.4.
C API¶
gh-98724: The
Py_CLEAR
,Py_SETREF
andPy_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.gh-98978: 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.gh-98410: Add
getbufferproc
andreleasebufferproc
to the stable API.gh-98610: Some configurable capabilities of sub-interpreters have changed. They always allow subprocesses (
subprocess
) now, whereas before subprocesses could be optionally disallowed for a sub-interpreter. Insteados.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, norPy_NewInterpreter()
.gh-98608: 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.gh-96853:
Py_InitializeEx
now correctly callsPyConfig_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)gh-91248: Add
PyFrame_GetVar()
andPyFrame_GetVarString()
functions to get a frame variable by its name. Patch by Victor Stinner.
Python 3.12.0 alpha 1¶
Release date: 2022-10-25
Security¶
gh-97616: Fix multiplying a list by an integer (
list *= int
): detect the integer overflow when the new allocated length is close to the maximum size. Issue reported by Jordan Limor. Patch by Victor Stinner.gh-97514: On Linux the
multiprocessing
module returns to using filesystem backed unix domain sockets for communication with the forkserver process instead of the Linux abstract socket namespace. Only code that chooses to use the «forkserver» start method is affected.Abstract sockets have no permissions and could allow any user on the system in the same network namespace (often the whole system) to inject code into the multiprocessing forkserver process. This was a potential privilege escalation. Filesystem based socket permissions restrict this to the forkserver process user as was the default in Python 3.8 and earlier.
This prevents Linux CVE-2022-42919.
gh-87389:
http.server
: Fix an open redirection vulnerability in the HTTP server when an URI path starts with//
. Vulnerability discovered, and initial fix proposed, by Hamza Avvan.gh-79096: LWPCookieJar and MozillaCookieJar create files with file mode 600 instead of 644 (Microsoft Windows is not affected)
gh-92888: Fix
memoryview
use after free when accessing the backing buffer in certain cases.gh-68966: The deprecated mailcap module now refuses to inject unsafe text (filenames, MIME types, parameters) into shell commands. Instead of using such text, it will warn and act as if a match was not found (or for test commands, as if the test failed).
Core and Builtins¶
gh-98374: Suppress ImportError for invalid query for help() command. Patch by Dong-hee Na.
gh-98461: Fix source location in bytecode for list, set and dict comprehensions as well as generator expressions.
gh-98354: Added unicode check for
name
attribute ofspec
argument passed in_imp.create_builtin()
function.gh-98398: Fix source location of “assert” bytecodes.
gh-98390: Fix location of sub-expressions of boolean expressions, by reducing their scope to that of the sub-expression.
gh-98254: Modules from the standard library are now potentially suggested as part of the error messages displayed by the interpreter when an
NameError
is raised to the top level. Patch by Pablo Galindogh-97997: Add running column offset to the tokenizer state to avoid calculating AST column information with pointer arithmetic.
gh-97973: Modify the tokenizer to return all necessary information the parser needs to set location information in the AST nodes, so that the parser does not have to calculate those doing pointer arithmetic.
gh-96078:
os.sched_yield()
now release the GIL while calling sched_yield(2). Patch by Dong-hee Na.gh-97912: The compiler now avoids quadratic behavior when finding which instructions should use the
LOAD_FAST_CHECK
opcode.gh-97002: Fix an issue where several frame objects could be backed by the same interpreter frame, possibly leading to corrupted memory and hard crashes of the interpreter.
gh-97943: Bugfix:
PyFunction_GetAnnotations()
should return a borrowed reference. It was returning a new reference.gh-97922: The Garbage Collector now runs only on the eval breaker mechanism of the Python bytecode evaluation loop instead on object allocations. The GC can also run when
PyErr_CheckSignals()
is called so C extensions that need to run for a long time without executing any Python code also have a chance to execute the GC periodically.gh-65961: When
__package__
is different than__spec__.parent
, raise aDeprecationWarning
instead ofImportWarning
.Also remove
importlib.util.set_package()
which was scheduled for removal.gh-97850: Long deprecated,
module_repr()
should now be completely eradicated.gh-86298: In cases where
warnings.warn_explicit()
consults the module’s loader, anDeprecationWarning
is issued whenm.__loader__
differs fromm.__spec__.loader
.gh-97779: Ensure that all Python frame objects are backed by «complete» frames.
gh-91052: Add API for subscribing to modification events on selected dictionaries.
gh-97752: Fix possible data corruption or crashes when accessing the
f_back
member of newly-created generator or coroutine frames.gh-97591: Fixed a missing incref/decref pair in
Exception.__setstate__()
. Patch by Ofey Chan.gh-97670: Remove the
sys.getdxp()
function and theTools/scripts/analyze_dxp.py
script. DXP stands for «dynamic execution pairs». They were related toDYNAMIC_EXECUTION_PROFILE
andDXPAIRS
macros which have been removed in Python 3.11. Python can now be built with./configure --enable-pystats
to gather statistics on Python opcodes. Patch by Victor Stinner.gh-94526: Fix the Python path configuration used to initialized
sys.path
at Python startup. Paths are no longer encoded to UTF-8/strict to avoid encoding errors if it contains surrogate characters (bytes paths are decoded with the surrogateescape error handler). Patch by Victor Stinner.gh-96670: The parser now raises
SyntaxError
when parsing source code containing null bytes. Patch by Pablo Galindogh-96975: Fix a crash occurring when
PyEval_GetFrame()
is called while the topmost Python frame is in a partially-initialized state.gh-96848: Fix command line parsing: reject
-X int_max_str_digits
option with no value (invalid) when thePYTHONINTMAXSTRDIGITS
environment variable is set to a valid limit. Patch by Victor Stinner.gh-95921: Fix overly-broad source position information for chained comparisons used as branching conditions.
gh-96821: Fix undefined behaviour in
audioop.c
.gh-96821: Fix undefined behaviour in
_testcapimodule.c
.gh-95778: When
ValueError
is raised if an integer is larger than the limit, mention thesys.set_int_max_str_digits()
function in the error message. Patch by Victor Stinner.gh-96387: At Python exit, sometimes a thread holding the GIL can wait forever for a thread (usually a daemon thread) which requested to drop the GIL, whereas the thread already exited. To fix the race condition, the thread which requested the GIL drop now resets its request before exiting. Issue discovered and analyzed by Mingliang ZHAO. Patch by Victor Stinner.
gh-96864: Fix a possible assertion failure, fatal error, or
SystemError
if a line tracing event raises an exception while opcode tracing is enabled.gh-95778: The
PyLong_FromString
function was refactored to make it more maintainable and extensible.gh-96678: Fix undefined behaviour in C code of null pointer arithmetic.
gh-96754: Make sure that all frame objects created are created from valid interpreter frames. Prevents the possibility of invalid frames in backtraces and signal handlers.
gh-90997: Improve the performance of reading and writing inline bytecode caches on some platforms.
gh-96751: Remove dead code from
CALL_FUNCTION_EX
opcode.gh-90751:
memoryview
now supports half-floats. Patch by Dong-hee Na and Antoine Pitrou.gh-96678: Fix case of undefined behavior in ceval.c
gh-64373: Convert
_functools
to argument clinic.gh-96641: Do not expose
KeyWrapper
in_functools
.gh-96636: Ensure that tracing,
sys.setrace()
, is turned on immediately. In pre-release versions of 3.11, some tracing events might have been lost when turning on tracing in a__del__
method or interrupt.gh-96572: Fix use after free in trace refs build mode. Patch by Kumar Aditya.
gh-96611: When loading a file with invalid UTF-8 inside a multi-line string, a correct SyntaxError is emitted.
gh-96612: Make sure that incomplete frames do not show up in tracemalloc traces.
gh-90230: Fix compiler warnings and test failures when building with
--enable-pystats
.gh-96587: Correctly raise
SyntaxError
on exception groups (PEP 654) on python versions prior to 3.11gh-96569: Remove two cases of undefined behavoir, by adding NULL checks.
gh-96582: Fix possible
NULL
pointer dereference in_PyThread_CurrentFrames
. Patch by Kumar Aditya.gh-91079: Separate Python recursion checking from C recursion checking which reduces the chance of C stack overflow and allows the recursion limit to be increased safely.
gh-93911: Fix an issue that could prevent
LOAD_ATTR
from specializing properly when accessing properties.gh-96348: Emit a DeprecationWarning when
throw()
,throw()
orathrow()
are called with more than one argument.gh-95196: Disable incorrect pickling of the C implemented classmethod descriptors.
gh-96364: Fix text signatures of
list.__getitem__
anddict.__getitem__
.gh-96352: Fix
AttributeError
missingname
andobj
attributes inobject.__getattribute__()
. Patch by Philip Georgi.gh-93554: Change the jump opcodes so that all conditional jumps are forward jumps. Backward jumps are converted by the assembler into a conditional forward jump whose target is the fallthrough block (and with a reversed condition), followed by an unconditional backward jump. For example:
POP_JUMP_IF_TRUE BACKWARD_TARGET
becomesPOP_JUMP_IF_FALSE NEXT_BLOCK; JUMP BACKWARD_TARGET
.All the directed conditional jump opcodes were removed:
POP_JUMP_FORWARD_IF_TRUE
,POP_JUMP_BACKWARD_IF_TRUE
,POP_JUMP_FORWARD_IF_FALSE
,POP_JUMP_BACKWARD_IF_FALSE
,POP_JUMP_FORWARD_IF_NONE
,POP_JUMP_BACKWARD_IF_NONE
,POP_JUMP_FORWARD_IF_NOT_NONE
,POP_JUMP_BACKWARD_IF_NOT_NONE
.The corresponding opcodes without direction are no longer pseudo-instructions, and they implement the forward conditional jumps.
gh-96268: Loading a file with invalid UTF-8 will now report the broken character at the correct location.
gh-96237: The internal field
_PyInterpreterFrame.f_func
is renamed to_PyInterpreterFrame.f_funcobj
and may be any object. Thef_globals
andf_builtin
fields may hold junk values.It is safest to treat the
_PyInterpreterFrame
struct as opaque.gh-96187: Fixed a bug that caused
_PyCode_GetExtra
to return garbage for negative indexes. Patch by Pablo Galindogh-96143: Add a new
-X perf
Python command line option as well assys.activate_stack_trampoline()
andsys.deactivate_stack_trampoline()
function in thesys
module that allows to set/unset the interpreter in a way that the Linuxperf
profiler can detect Python calls. The newsys.is_stack_trampoline_active()
function allows to query the state of the perf trampoline. Design by Pablo Galindo. Patch by Pablo Galindo and Christian Heimes with contributions from Gregory P. Smith [Google] and Mark Shannon.gh-96071: Fix a deadlock in
PyGILState_Ensure()
when allocating new thread state. Patch by Kumar Aditya.gh-96046:
PyType_Ready()
now initializesht_cached_keys
and performs additional checks to ensure that type objects are properly configured. This avoids crashes in 3rd party packages that don’t use regular API to create new types.gh-96005: On WASI
ENOTCAPABLE
is now mapped toPermissionError
. Theerrno
modules exposes the new error number.getpath.py
now ignoresPermissionError
when it cannot open landmark filespybuilddir.txt
andpyenv.cfg
.gh-93678: Added test a harness for direct unit tests of the compiler’s optimization stage. The
_testinternalcapi.optimize_cfg()
function runs the optimiser on a sequence of instructions. TheCfgOptimizationTestCase
class intest.support
has utilities for invoking the optimizer and checking the output.gh-95245: Reduces the size of a «simple» Python object from 8 to 6 words by moving the weakreflist pointer into the pre-header directly before the object’s dict/values pointer.
gh-90997: Compile virtual
try
/except
blocks to handle exceptions raised duringclose()
orthrow()
calls through a suspended frame.gh-95977: Optimized calling
__get__()
with vectorcall. Patch by Kumar Aditya.gh-91210: Improve error message when a parameter without a default value follows one with a default value, and show the same message, even when the non-default/default sequence is preceded by positional-only parameters.
gh-95922: Fixed bug where the compiler’s
eliminate_empty_basic_blocks
function ignores the last block of the code unit.gh-95818: Skip over incomplete frames in
PyThreadState_GetFrame()
.gh-95876: Fix format string in
_PyPegen_raise_error_known_location
that can lead to memory corruption on some 64bit systems. The function was building a tuple withi
(int) instead ofn
(Py_ssize_t) for Py_ssize_t arguments.gh-95605: Fix misleading contents of error message when converting an all-whitespace string to
float
.gh-95150: Update code object hashing and equality to consider all debugging and exception handling tables. This fixes an issue where certain non-identical code objects could be «deduplicated» during compilation.
gh-91146: Reduce allocation size of
list
fromstr.split()
andstr.rsplit()
. Patch by Dong-hee Na and Inada Naoki.gh-87092: Create a “jump target label” abstraction in the compiler so that the compiler’s codegen stage does not work directly with basic blocks. This prepares the code for changes to the underlying CFG generation mechanism.
gh-95355:
_PyPegen_Parser_New
now properly detects token memory allocation errors. Patch by Honglin Zhu.gh-90081: Run Python code in tracer/profiler function at full speed. Fixes slowdown in earlier versions of 3.11.
gh-95324: Emit a warning in debug mode if an object does not call
PyObject_GC_UnTrack()
before deallocation. Patch by Pablo Galindo.gh-95245: Merge managed dict and values pointer into a single tagged pointer to save one word in the pre-header.
gh-93678: Add cfg_builder struct and refactor the relevant code so that a cfg can be constructed without an instance of the compiler struct.
gh-95185: Prevented crashes in the AST constructor when compiling some absurdly long expressions like
"+0"*1000000
.RecursionError
is now raised instead. Patch by Pablo Galindogh-93351:
ast.AST
node positions are now validated when provided tocompile()
and other related functions. If invalid positions are detected, aValueError
will be raised.gh-94438: Fix an issue that caused extended opcode arguments and some conditional pops to be ignored when calculating valid jump targets for assignments to the
f_lineno
attribute of frame objects. In some cases, this could cause inconsistent internal state, resulting in a hard crash of the interpreter.gh-95060: Undocumented
PyCode_Addr2Location
function now properly returns whenaddrq
argument is less than zero.gh-95113: Replace all
EXTENDED_ARG_QUICK
instructions with basicEXTENDED_ARG
instructions in unquickened code. Consumers of non-adaptive bytecode should be able to handle extended arguments the same way they were handled in CPython 3.10 and older.gh-91409: Fix incorrect source location info caused by certain optimizations in the bytecode compiler.
gh-95023: Implement
os.setns()
andos.unshare()
for Linux. Patch by Noam Cohen.gh-94036: Fix incorrect source location info for some multi-line attribute accesses and method calls.
gh-94938: Fix error detection in some builtin functions when keyword argument name is an instance of a str subclass with overloaded
__eq__
and__hash__
. Previously it could cause SystemError or other undesired behavior.gh-94996:
ast.parse()
will no longer parse function definitions with positional-only params when passedfeature_version
less than(3, 8)
. Patch by Shantanu Jain.gh-94739: Allow jumping within, out of, and across exception handlers in the debugger.
gh-94949:
ast.parse()
will no longer parse parenthesized context managers when passedfeature_version
less than(3, 9)
. Patch by Shantanu Jain.gh-94947:
ast.parse()
will no longer parse assignment expressions when passedfeature_version
less than(3, 8)
. Patch by Shantanu Jain.gh-91256: Ensures the program name is known for help text during interpreter startup.
gh-94869: Fix the column offsets for some expressions in multi-line f-strings
ast
nodes. Patch by Pablo Galindo.gh-94893: Fix an issue where frame object manipulations could corrupt inline bytecode caches.
gh-94822: Fix an issue where lookups of metaclass descriptors may be ignored when an identically-named attribute also exists on the class itself.
gh-91153: Fix an issue where a
bytearray
item assignment could crash if it’s resized by the new value’s__index__()
method.gh-90699: Fix reference counting bug in
bool.__repr__()
. Patch by Kumar Aditya.gh-94694: Fix an issue that could cause code with multi-line method lookups to have misleading or incorrect column offset information. In some cases (when compiling a hand-built AST) this could have resulted in a hard crash of the interpreter.
gh-93252: Fix an issue that caused internal frames to outlive failed Python function calls, possibly resulting in memory leaks or hard interpreter crashes.
gh-94215: Fix an issue where exceptions raised by line-tracing events would cause frames to be left in an invalid state, possibly resulting in a hard crash of the interpreter.
gh-92228: Disable the compiler’s inline-small-exit-blocks optimization for exit blocks that are associated with source code lines. This fixes a bug where the debugger cannot tell where an exception handler ends and the following code block begins.
gh-94485: Line number of a module’s
RESUME
instruction is set to 0 as specified in PEP 626.gh-94438: Account for instructions that can push NULL to the stack when setting line number in a frame. Prevents some (unlikely) crashes.
gh-91719: Reload
opcode
when raisingunknown opcode error
in the interpreter main loop, for C compilers to generate dispatching code independently.gh-94329: Compile and run code with unpacking of extremely large sequences (1000s of elements). Such code failed to compile. It now compiles and runs correctly.
gh-94360: Fixed a tokenizer crash when reading encoded files with syntax errors from
stdin
with non utf-8 encoded text. Patch by Pablo Galindogh-88116: Fix an issue when reading line numbers from code objects if the encoded line numbers are close to
INT_MIN
. Patch by Pablo Galindogh-94262: Don’t create frame objects for incomplete frames. Prevents the creation of generators and closures from being observable to Python and C extensions, restoring the behavior of 3.10 and earlier.
gh-94192: Fix error for dictionary literals with invalid expression as value.
gh-87995:
types.MappingProxyType
instances are now hashable if the underlying mapping is hashable.gh-93883: Revise the display strategy of traceback enhanced error locations. The indicators are only shown when the location doesn’t span the whole line.
gh-94163: Add
BINARY_SLICE
andSTORE_SLICE
instructions for more efficient handling and better specialization of slicing operations, where the slice is explicit in the source code.gh-94021: Fix unreachable code warning in
Python/specialize.c
.gh-93911: Specialize
LOAD_ATTR
for objects with custom__getattribute__
.gh-93955: Improve performance of attribute lookups on objects with custom
__getattribute__
and__getattr__
. Patch by Ken Jin.gh-93911: Specialize
LOAD_ATTR
forproperty()
attributes.gh-93678: Refactor compiler optimisation code so that it no longer needs the
struct assembler
andstruct compiler
passed around. Instead, each function takes the CFG and other data that it actually needs. This will make it possible to test this code directly.gh-93841: When built with
-enable-pystats
,sys._stats_on()
,sys._stats_off()
,sys._stats_clear()
andsys._stats_dump()
functions have been added to enable gathering stats for parts of programs.gh-93516: Store offset of first traceable instruction in code object to avoid having to recompute it for each instruction when tracing.
gh-93516: Lazily create a table mapping bytecode offsets to line numbers to speed up calculation of line numbers when tracing.
gh-89828:
types.GenericAlias
no longer relays the__class__
attribute. For example,isinstance(list[int], type)
no longer returnsTrue
.gh-93678: Refactor the compiler to reduce boilerplate and repetition.
gh-93671: Fix some exponential backtrace case happening with deeply nested sequence patterns in match statements. Patch by Pablo Galindo
gh-93662: Make sure that the end column offsets are correct in multi-line method calls. Previously, the end column could precede the column offset.
gh-93461:
importlib.invalidate_caches()
now drops entries fromsys.path_importer_cache
with a relative path as name. This solves a caching issue when a process changes its current working directory.FileFinder
no longer inserts a dot in the path, e.g./egg/./spam
is now/egg/spam
.gh-93621: Change order of bytecode instructions emitted for
with
andasync with
to reduce the number of entries in the exception table.gh-93533: Reduce the size of the inline cache for
LOAD_METHOD
by 2 bytes.gh-93444: Removed redundant fields from the compiler’s basicblock struct:
b_nofallthrough
,b_exit
,b_return
. They can be easily calculated from the opcode of the last instruction of the block.gh-93429:
LOAD_METHOD
instruction has been removed. It was merged back intoLOAD_ATTR
.gh-93418: Fixed an assert where an f-string has an equal sign “=” following an expression, but there’s no trailing brace. For example, f»{i=».
gh-93382: Cache the result of
PyCode_GetCode()
function to restore the O(1) lookup of theco_code
attribute.gh-93359: Ensure that custom
ast
nodes without explicit end positions can be compiled. Patch by Pablo Galindo.gh-93356: Code for exception handlers is emitted at the end of the code unit’s bytecode. This avoids one jump when no exception is raised.
gh-93354: Use exponential backoff for specialization counters in the interpreter. Can reduce the number of failed specializations significantly and avoid slowdown for those parts of a program that are not suitable for specialization.
gh-93283: Improve error message for invalid syntax of conversion character in f-string expressions.
gh-93345: Fix a crash in substitution of a
TypeVar
in nested generic alias afterTypeVarTuple
.gh-93223: When a bytecode instruction jumps to an unconditional jump instruction, the first instruction can often be optimized to target the unconditional jump’s target directly. For tracing reasons, this would previously only occur if both instructions have the same line number. This also now occurs if the unconditional jump is artificial, i.e., if it has no associated line number.
gh-84694: The
--experimental-isolated-subinterpreters
configure option andEXPERIMENTAL_ISOLATED_SUBINTERPRETERS
macro have been removed.gh-91924: Fix
__lltrace__
debug feature if the stdout encoding is not UTF-8. Patch by Victor Stinner.gh-93040: Wraps unused parameters in
Objects/obmalloc.c
withPy_UNUSED
.gh-93143: Avoid
NULL
checks for uninitialized local variables by determining at compile time which variables must be initialized.gh-93061: Backward jumps after
async for
loops are no longer given dubious line numbers.gh-93065: Fix contextvars HAMT implementation to handle iteration over deep trees.
The bug was discovered and fixed by Eli Libman. See MagicStack/immutables#84 for more details.
gh-93012: Added the new function
PyType_FromMetaclass()
, which generalizes the existingPyType_FromModuleAndSpec()
using an additional metaclass argument. This is useful for language binding tools, where it can be used to intercept type-related operations like subclassing or static attribute access by specifying a metaclass with custom slots.Importantly,
PyType_FromMetaclass()
is available in the Limited API, which provides a path towards migrating more binding tools onto the Stable ABI.gh-93021: Fix the
__text_signature__
for__get__()
methods implemented in C. Patch by Jelle Zijlstra.gh-89914: The operand of the
YIELD_VALUE
instruction is set to the stack depth. This is done to help frame handling onyield
and may assist debuggers.gh-92955: Fix memory leak in code object’s lines and positions iterators as they were not finalized at exit. Patch by Kumar Aditya.
gh-92930: Fixed a crash in
_pickle.c
from mutating collections during__reduce__
orpersistent_id
.gh-90690: The PRECALL instruction has been removed. It offered only a small advantage for specialization and is not needed in the vast majority of cases.
gh-92914: Always round the allocated size for lists up to the nearest even number.
gh-92858: Improve error message for some suites with syntax error before “:”
gh-90473: Decrease default recursion limit on WASI to address limited call stack size.
gh-92804: Fix memory leak in
memoryview
iterator as it was not finalized at exit. Patch by Kumar Aditya.gh-92777: Specialize
LOAD_METHOD
for objects with lazy dictionaries. Patch by Ken Jin.gh-92658: Add support for connecting and binding to Hyper-V sockets on Windows Hyper-V hosts and guests.
gh-92236: Remove spurious «LINE» event when starting a generator or coroutine, visible tracing functions implemented in C.
gh-91102:
_warnings.warn_explicit()
is ported to Argument Clinic.gh-92619: Make the compiler duplicate an exit block only if none of its instructions have a lineno (previously only the first instruction in the block was checked, leading to unnecessarily duplicated blocks).
gh-88750: The deprecated debug build only
PYTHONTHREADDEBUG
environment variable no longer does anything.gh-92261: Fix hang when trying to iterate over a
typing.Union
.gh-91432: Specialized the
FOR_ITER
opcode using the PEP 659 machinerygh-91399: Removed duplicate “{0, 0, 0, 0, 0, 0}” entry in “Objects/unicodetype_db.h”.
gh-91578: Updates the error message for abstract class.
bpo-47091: Improve performance of repetition of
list
andtuple
by usingmemcpy
to copy data and performing the reference increments in one step.bpo-46142: Make
--help
output shorter by moving some info to the new--help-env
and--help-xoptions
command-line options. Also add--help-all
option to print complete usage.bpo-42316: Document some places where an assignment expression needs parentheses.
Library¶
gh-89237: Fix hang on Windows in
subprocess.wait_closed()
inasyncio
withProactorEventLoop
. Patch by Kumar Aditya.gh-97928:
tkinter.Text.count()
raises now an exception for options starting with «-» instead of silently ignoring them.gh-98393: The
os
module no longer accepts bytes-like paths, likebytearray
andmemoryview
types: only the exactbytes
type is accepted for bytes strings. Patch by Victor Stinner.gh-98363: Added itertools.batched() to batch data into lists of a given length with the last list possibly being shorter than the others.
gh-98331: Update the bundled copies of pip and setuptools to versions 22.3 and 65.5.0 respectively.
gh-98307: A
createSocket()
method was added toSysLogHandler
.gh-96035: Fix bug in
urllib.parse.urlparse()
that causes certain port numbers containing whitespace, underscores, plus and minus signs, or non-ASCII digits to be incorrectly accepted.gh-98257: Make
sys.setprofile()
andsys.settrace()
functions reentrant. They can no long fail with:RuntimeError("Cannot install a trace function while another trace function is being installed")
. Patch by Victor Stinner.gh-98251: Allow
venv
to pass alongPYTHON*
variables toensurepip
andpip
when they do not impact path resolutiongh-94597: Deprecated
asyncio.AbstractEventLoopPolicy.get_child_watcher()
andasyncio.AbstractEventLoopPolicy.set_child_watcher()
methods to be removed in Python 3.14. Patch by Kumar Aditya.gh-98178: On macOS, fix a crash in
syslog.syslog()
in multi-threaded applications. On macOS, the libcsyslog()
function is not thread-safe, sosyslog.syslog()
no longer releases the GIL to call it. Patch by Victor Stinner.gh-44098: Release the GIL when creating
mmap.mmap
objects on Unix.gh-87730: Wrap network errors consistently in urllib FTP support, so the test suite doesn’t fail when a network is available but the public internet is not reachable.
gh-94597: The child watcher classes
MultiLoopChildWatcher
,FastChildWatcher
andSafeChildWatcher
are deprecated and will be removed in Python 3.14. Patch by Kumar Aditya.gh-98023: Change default child watcher to
PidfdChildWatcher
on Linux systems which supports it. Patch by Kumar Aditya.gh-90985: Earlier in 3.11 we deprecated
asyncio.Task.cancel("message")
. We realized we were too harsh, and have undeprecated it.gh-65961: Do not rely solely on
__cached__
on modules; code will also support__spec__.cached
.gh-97646: Replace deprecated
application/javascript
withtext/javascript
inmimetypes
. See RFC 9239. Patch by Noam Cohen.gh-97930: Apply changes from importlib_resources 5.8 and 5.9:
Traversable.joinpath
provides a concrete implementation.as_file
now supports directories of resources.gh-97850: Remove deprecated
importlib.utils.set_loader()
andimportlib.utils.module_for_loader()
fromimportlib.utils
.gh-97837: Change deprecate warning message in
unittest
fromIt is deprecated to return a value!=None
to
It is deprecated to return a value that is not None from a test case
gh-97825: Fixes
AttributeError
whensubprocess.check_output()
is used with argumentinput=None
and either of the arguments encoding or errors are used.gh-97008:
NameError
andAttributeError
spelling suggestions provided since gh-82711 are now also emitted by the pure Pythontraceback
module. Tests for those suggestions now exercise both implementations to ensure they are equivalent. Patch by Carl Friedrich Bolz-Tereick and Łukasz Langa.gh-97799:
dataclass
now usesinspect.get_annotations()
to examine the annotations on class objects.gh-97781: Removed deprecated interfaces in
importlib.metadata
(entry points accessed as dictionary, implicit dictionary construction of sequence ofEntryPoint
objects, mutablility ofEntryPoints
result, access of entry point by index).entry_points
now has a simpler, more straightforward API (returningEntryPoints
).gh-96827: Avoid spurious tracebacks from
asyncio
when default executor cleanup is delayed until after the event loop is closed (e.g. as the result of a keyboard interrupt).gh-95534:
gzip.GzipFile.read()
reads 10% faster.gh-97592: Avoid a crash in the C version of
asyncio.Future.remove_done_callback()
when an evil argument is passed.gh-97545: Make Semaphore run faster.
gh-73588: Fix generation of the default name of
tkinter.Checkbutton
. Previously, checkbuttons in different parent widgets could have the same short name and share the same state if arguments «name» and «variable» are not specified. Now they are globally unique.gh-96865: fix Flag to use boundary CONFORM
This restores previous Flag behavior of allowing flags with non-sequential values to be combined; e.g.
class Skip(Flag): TWO = 2 EIGHT = 8
Skip.TWO | Skip.EIGHT -> <Skip.TWO|EIGHT: 10>
gh-97005: Update bundled libexpat to 2.4.9
gh-85760: Fix race condition in
asyncio
whereprocess_exited()
called before thepipe_data_received()
leading to inconsistent output. Patch by Kumar Aditya.gh-96704: Pass the correct
contextvars.Context
when aasyncio
exception handler is called on behalf of a task or callback handle. This adds a newTask
method,get_context
, and also a newHandle
method with the same name. If this method is not found on a task object (perhaps because it is a third-party library that does not yet provide this method), the context prevailing at the time the exception handler is called is used.gh-96819: Fixed check in
multiprocessing.resource_tracker
that guarantees that the length of a write to a pipe is not greater thanPIPE_BUF
.gh-95865: Reduce
urllib.parse.quote_from_bytes()
memory use on large values.Contributed by Dennis Sweeney.
gh-96741: Corrected type annotation for dataclass attribute
pstats.FunctionProfile.ncalls
to bestr
.gh-96734: Update
unicodedata
database to Unicode 15.0.0.gh-96735: Fix undefined behaviour in
struct.unpack()
.gh-46412: Improve performance of
bool(db)
for large ndb/gdb databases. Previously this would calllen(db)
which would iterate over all keys – the answer (empty or not) is known after the first key.gh-96652: Fix the faulthandler implementation of
faulthandler.register(signal, chain=True)
if thesigaction()
function is not available: don’t call the previous signal handler if it’s NULL. Patch by Victor Stinner.gh-68163: Correct conversion of
numbers.Rational
’s tofloat
.gh-96538: Speed up
bisect.bisect()
functions by taking advantage of type-stability.gh-96465: Fraction hashes are now cached.
gh-96079: In
typing
, fix missing fieldname
and incorrect__module__
in _AnnotatedAlias.gh-96415: Remove
types._cell_factory
from module namespace.gh-95987: Fix
repr
ofAny
subclasses.gh-96388: Work around missing socket functions in
socket
’s__repr__
.gh-96385: Fix
TypeVarTuple.__typing_prepare_subst__
.TypeError
was not raised when using more than oneTypeVarTuple
, like[*T, *V]
in type alias substitutions.gh-96142: Add
match_args
,kw_only
,slots
, andweakref_slot
to_DataclassParams
.gh-96073: In
inspect
, fix overeager replacement of «typing.
» in formatting annotations.gh-89258: Added a
getChildren()
method tologging.Logger
, to get the immediate child loggers of a logger.gh-96346: Use double caching for compiled RE patterns.
gh-96349: Fixed a minor performance regression in
threading.Event.__init__()
gh-90467: Fix
asyncio.streams.StreamReaderProtocol
to keep a strong reference to the created task, so that it’s not garbage collectedgh-96172: Fix a bug in
unicodedata
:east_asian_width
used to return the wrong value for unassigned characters; and for yet unassigned, but reserved characters.gh-96159: Fix a performance regression in logging TimedRotatingFileHandler. Only check for special files when the rollover time has passed.
gh-96175: Fix unused
localName
parameter in theAttr
class inxml.dom.minidom
.gh-96145: Add AttrDict to JSON module for use with object_hook.
gh-96052: Fix handling compiler warnings (SyntaxWarning and DeprecationWarning) in
codeop.compile_command()
when checking for incomplete input. Previously it emitted warnings and raised a SyntaxError. Now it always returnsNone
for incomplete input without emitting any warnings.gh-96125: Fix incorrect condition that causes
sys.thread_info.name
to be wrong on pthread platforms.gh-96019: Fix a bug in the
makeunicodedata.py
script leading to about 13 KiB of space saving in theunicodedata
module, specifically the character decomposition data.gh-95463: Remove an incompatible change from bpo-28080 that caused a regression that ignored the utf8 in
ZipInfo.flag_bits
. Patch by Pablo Galindo.gh-69142: Add
%:z
strftime format code (generates tzoffset with colons as separator), see Comportamiento strftime() y strptime().gh-95899: Fix
asyncio.Runner
to callasyncio.set_event_loop()
only once to avoid callingattach_loop()
multiple times on child watchers. Patch by Kumar Aditya.gh-95736: Fix
unittest.IsolatedAsyncioTestCase
to set event loop before calling setup functions. Patch by Kumar Aditya.gh-95865: Speed up
urllib.parse.quote_from_bytes()
by replacing a list comprehension withmap()
.gh-95861: Add support for computing Spearman’s correlation coefficient to the existing statistics.correlation() function.
gh-95804: Fix
logging
shutdown handler so it respectsMemoryHandler.flushOnClose
.gh-95704: When a task catches
asyncio.CancelledError
and raises some other error, the other error should generally not silently be suppressed.gh-95149: The
HTTPStatus
enum offers a couple of properties to indicate the HTTP status category e.g.HTTPStatus.OK.is_success
.gh-95609: Update bundled pip to 22.2.2.
gh-95289: Fix
asyncio.TaskGroup
to propagate exception whenasyncio.CancelledError
was replaced with another exception by a context manger. Patch by Kumar Aditya and Guido van Rossum.gh-94909: Fix incorrect joining of relative Windows paths with drives in
pathlib.PurePath
initializer.gh-95385: Faster
json.dumps()
when sorting of keys is not requested (default).gh-83901: Improve
Signature.bind
error message for missing keyword-only arguments.gh-95339: Update bundled pip to 22.2.1.
gh-95045: Fix GC crash when deallocating
_lsprof.Profiler
by untracking it before calling any callbacks. Patch by Kumar Aditya.gh-95231: Fail gracefully if
EPERM
orENOSYS
is raised when loadingcrypt
methods. This may happen when trying to loadMD5
on a Linux kernel with FIPS enabled.gh-95097: Fix
asyncio.run()
forasyncio.Task
implementations withoutuncancel()
method. Patch by Kumar Aditya.gh-95087: Fix IndexError in parsing invalid date in the
email
module.gh-95199: Upgrade bundled setuptools to 63.2.0.
gh-95194: Upgrade bundled pip to 22.2.
gh-93899: Fix check for existence of
os.EFD_CLOEXEC
,os.EFD_NONBLOCK
andos.EFD_SEMAPHORE
flags on older kernel versions where these flags are not present. Patch by Kumar Aditya.gh-95166: Fix
concurrent.futures.Executor.map()
to cancel the currently waiting on future on an error - e.g. TimeoutError or KeyboardInterrupt.gh-95132: Fix a
sqlite3
regression where*args
and**kwds
were incorrectly relayed fromconnect()
to theConnection
factory. The regression was introduced in 3.11a1 with PR 24421 (gh-85128). Patch by Erlend E. Aasland.`gh-93157: Fix
fileinput
module didn’t supporterrors
option wheninplace
is true.gh-91212: Fixed flickering of the turtle window when the tracer is turned off. Patch by Shin-myoung-serp.
gh-95077: Add deprecation warning for enum
member.member
access (e.g.Color.RED.BLUE
).gh-95109: Ensure that timeouts scheduled with
asyncio.Timeout
that have already expired are delivered promptly.gh-95105:
wsgiref.types.InputStream.__iter__()
should returnIterator[bytes]
, notIterable[bytes]
. Patch by Shantanu Jain.gh-95066: Replaced assert with exception in
ast.parse()
, whenfeature_version
has an invalid major version. Patch by Shantanu Jain.gh-77617: Add
sqlite3
command-line interface. Patch by Erlend Aasland.gh-95005: Replace _PyAccu with _PyUnicodeWriter in JSON encoder and StringIO and remove the _PyAccu implementation.
gh-90085: Remove
-c/--clock
and-t/--time
CLI options oftimeit
. The options had been deprecated since Python 3.3 and the functionality was removed in Python 3.7. Patch by Shantanu Jain.gh-94857: Fix refleak in
_io.TextIOWrapper.reconfigure
. Patch by Kumar Aditya.gh-94821: Fix binding of unix socket to empty address on Linux to use an available address from the abstract namespace, instead of «0».
gh-94736: Fix crash when deallocating an instance of a subclass of
_multiprocessing.SemLock
. Patch by Kumar Aditya.gh-81620: Add random.binomialvariate().
gh-74116: Allow
asyncio.StreamWriter.drain()
to be awaited concurrently by multiple tasks. Patch by Kumar Aditya.gh-87822: When called with
capture_locals=True
, thetraceback
module functions swallow exceptions raised from calls torepr()
on local variables of frames. This is in order to prioritize the original exception over rendering errors. An indication of the failure is printed in place of the missing value. (Patch by Simon-Martin Schroeder).gh-88050: Fix
asyncio
subprocess transport to kill process cleanly when process is blocked and avoidRuntimeError
when loop is closed. Patch by Kumar Aditya.gh-94637:
SSLContext.set_default_verify_paths()
now releases the GIL aroundSSL_CTX_set_default_verify_paths
call. The function call performs I/O and CPU intensive work.gh-94309: Deprecate aliases
typing.Hashable
andtyping.Sized
gh-92546: An undocumented
python -m pprint
benchmark is moved intopprint
suite of pyperformance. Patch by Oleg Iarygin.gh-94607: Fix subclassing complex generics with type variables in
typing
. Previously an error message sayingSome type variables ... are not listed in Generic[...]
was shown.typing
no longer populates__parameters__
with the__parameters__
of a Python class.gh-94619: Remove the long-deprecated
module_repr()
fromimportlib
.gh-93910: The ability to access the other values of an enum on an enum (e.g.
Color.RED.BLUE
) has been restored in order to fix a performance regression.gh-93896: Fix
asyncio.run()
andunittest.IsolatedAsyncioTestCase
to always the set event loop as it was done in Python 3.10 and earlier. Patch by Kumar Aditya.gh-94343: Allow setting the attributes of
reprlib.Repr
during object initializationgh-94382: Port static types of
_multiprocessing
module to heap types. Patch by Kumar Aditya.gh-78724: Fix crash in
struct.Struct
when it was not completely initialized by initializing it in__new__`()
. Patch by Kumar Aditya.gh-94510: Re-entrant calls to
sys.setprofile()
andsys.settrace()
now raiseRuntimeError
. Patch by Pablo Galindo.gh-92336: Fix bug where
linecache.getline()
fails on bad files withUnicodeDecodeError
orSyntaxError
. It now returns an empty string as per the documentation.gh-94398: Once a
asyncio.TaskGroup
has started shutting down (i.e., at least one task has failed and the task group has started cancelling the remaining tasks), it should not be possible to add new tasks to the task group.gh-94383:
xml.etree
: Remove theElementTree.Element.copy()
method of the pure Python implementation, deprecated in Python 3.10, use thecopy.copy()
function instead. The C implementation ofxml.etree
has nocopy()
method, only a__copy__()
method. Patch by Victor Stinner.gh-94379:
zipimport
: Removefind_loader()
andfind_module()
methods, deprecated in Python 3.10: use thefind_spec()
method instead. See PEP 451 for the rationale. Patch by Victor Stinner.gh-94352:
shlex.split()
: PassingNone
for s argument now raises an exception, rather than readingsys.stdin
. The feature was deprecated in Python 3.9. Patch by Victor Stinner.gh-89988: Fix memory leak in
pickle.Pickler
when looking updispatch_table
. Patch by Kumar Aditya.gh-90016: Deprecate
sqlite3
default adapters and converters. Patch by Erlend E. Aasland.gh-94254: Fixed types of
struct
module to be immutable. Patch by Kumar Aditya.gh-93259: Now raise
ValueError
whenNone
or an empty string are passed toDistribution.from_name
(and other callers).gh-74696:
shutil.make_archive()
now passes the root_dir argument to custom archivers which support it.gh-94216: The
dis
module now has the opcodes for pseudo instructions (those which are used by the compiler during code generation but then removed or replaced by real opcodes before the final bytecode is emitted).gh-93096: Removed undocumented
python -m codecs
. Usepython -m unittest test.test_codecs.EncodedFileTest
instead.gh-94207: Made
_struct.Struct
GC-tracked in order to fix a reference leak in the_struct
module.gh-93096: Removed undocumented
-t
argument ofpython -m base64
. Usepython -m unittest test.test_base64.LegacyBase64TestCase.test_encodebytes
instead.gh-94226: Remove the
locale.format()
function, deprecated in Python 3.7: uselocale.format_string()
instead. Patch by Victor Stinner.gh-94199: Remove the
ssl.match_hostname()
function. Thessl.match_hostname()
was deprecated in Python 3.7. OpenSSL performs hostname matching since Python 3.7, Python no longer uses thessl.match_hostname()
function. Patch by Victor Stinner.gh-94214: Document the
context
object used in thevenv.EnvBuilder
class, and add the new environment’s library path to it.gh-94199: Remove the
ssl.wrap_socket()
function, deprecated in Python 3.7: instead, create assl.SSLContext
object and call itsssl.SSLContext.wrap_socket
method. Any package that still usesssl.wrap_socket()
is broken and insecure. The function neither sends a SNI TLS extension nor validates server hostname. Code is subject to CWE-295: Improper Certificate Validation. Patch by Victor Stinner.gh-94199: Remove the
ssl.RAND_pseudo_bytes()
function, deprecated in Python 3.6: useos.urandom()
orssl.RAND_bytes()
instead. Patch by Victor Stinner.gh-94199:
hashlib
: Remove the pure Python implementation ofhashlib.pbkdf2_hmac()
, deprecated in Python 3.10. Python 3.10 and newer requires OpenSSL 1.1.1 (PEP 644): this OpenSSL version provides a C implementation ofpbkdf2_hmac()
which is faster. Patch by Victor Stinner.gh-94196:
gzip
: Remove thefilename
attribute ofgzip.GzipFile
, deprecated since Python 2.6, use thename
attribute instead. In write mode, thefilename
attribute added'.gz'
file extension if it was not present. Patch by Victor Stinner.gh-94182: run the
asyncio.PidfdChildWatcher
on the running loop, this allows event loops to run subprocesses when there is no default event loop running on the main threadgh-94169: Remove
io.OpenWrapper
and_pyio.OpenWrapper
, deprecated in Python 3.10: just useopen()
instead. Theopen()
(io.open()
) function is a built-in function. Since Python 3.10,_pyio.open()
is also a static method. Patch by Victor Stinner.gh-91742: Fix
pdb
crash after jump caused by a null pointer dereference. Patch by Kumar Aditya.gh-94101: Manual instantiation of
ssl.SSLSession
objects is no longer allowed as it lead to misconfigured instances that crashed the interpreter when attributes where accessed on them.gh-84753:
inspect.iscoroutinefunction()
,inspect.isgeneratorfunction()
, andinspect.isasyncgenfunction()
now properly returnTrue
for duck-typed function-like objects like instances ofunittest.mock.AsyncMock
.This makes
inspect.iscoroutinefunction()
consistent with the behavior ofasyncio.iscoroutinefunction()
. Patch by Mehdi ABAAKOUK.gh-94028: Fix a regression in the
sqlite3
where statement objects were not properly cleared and reset after use in cursor iters. The regression was introduced by PR 27884 in Python 3.11a1. Patch by Erlend E. Aasland.gh-93973: Add keyword argument
all_errors
toasyncio.create_connection
so that multiple connection errors can be raised as anExceptionGroup
.gh-93963: Officially deprecate from
importlib.abc
classes moved toimportlib.resources.abc
.gh-93858: Prevent error when activating venv in nested fish instances.
gh-93847: Fix repr of enum of generic aliases.
gh-91404: Revert the
re
memory leak when a match is terminated by a signal or memory allocation failure as the implemented fix caused a major performance regression.gh-83499: Fix double closing of file description in
tempfile
.gh-93820: Fixed a regression when
copy.copy()
-ingenum.Flag
with multiple flag members.gh-79512: Fixed names and
__module__
value ofweakref
classesReferenceType
,ProxyType
,CallableProxyType
. It makes them pickleable.gh-91389: Fix an issue where
dis
utilities could report missing or incorrect position information in the presence ofCACHE
entries.gh-93626: Set
__future__.annotations
to have aNone
mandatoryRelease to indicate that it is currently “TBD”.gh-90473: Emscripten and WASI have no home directory and cannot provide PEP 370 user site directory.
gh-90494:
copy.copy()
andcopy.deepcopy()
now always raise a TypeError if__reduce__()
returns a tuple with length 6 instead of silently ignore the 6th item or produce incorrect result.gh-90549: Fix a multiprocessing bug where a global named resource (such as a semaphore) could leak when a child process is spawned (as opposed to forked).
gh-93521: Fixed a case where dataclasses would try to add
__weakref__
into the__slots__
for a dataclass that specifiedweakref_slot=True
when it was already defined in one of its bases. This resulted in aTypeError
upon the new class being created.gh-79579:
sqlite3
now correctly detects DML queries with leading comments. Patch by Erlend E. Aasland.gh-93421: Update
sqlite3.Cursor.rowcount
when a DML statement has run to completion. This fixes the row count for SQL queries likeUPDATE ... RETURNING
. Patch by Erlend E. Aasland.gh-93475: Expose
FICLONE
andFICLONERANGE
constants infcntl
. Patch by Illia Volochii.gh-93370: Deprecate
sqlite3.version
andsqlite3.version_info
.gh-91810: Suppress writing an XML declaration in open files in
ElementTree.write()
withencoding='unicode'
andxml_declaration=None
.gh-91162: Support splitting of unpacked arbitrary-length tuple over
TypeVar
andTypeVarTuple
parameters. For example:A[T, *Ts][*tuple[int, ...]]
->A[int, *tuple[int, ...]]
A[*Ts, T][*tuple[int, ...]]
->A[*tuple[int, ...], int]
gh-93353: Fix the
importlib.resources.as_file()
context manager to remove the temporary file if destroyed late during Python finalization: keep a local reference to theos.remove()
function. Patch by Victor Stinner.gh-83658: Make
multiprocessing.Pool
raise an exception ifmaxtasksperchild
is notNone
or a positive int.gh-93312: Add
os.PIDFD_NONBLOCK
flag to open a file descriptor for a process withos.pidfd_open()
in non-blocking mode. Patch by Kumar Aditya.gh-88123: Implement Enum __contains__ that returns True or False to replace the deprecated behaviour that would sometimes raise a TypeError.
gh-93297: Make asyncio task groups prevent child tasks from being GCed
gh-85308: Changed
argparse.ArgumentParser
to use filesystem encoding and error handler instead of default text encoding to read arguments from file (e.g.fromfile_prefix_chars
option). This change affects Windows; argument file should be encoded with UTF-8 instead of ANSI Codepage.gh-93156: Accessing the
pathlib.PurePath.parents
sequence of an absolute path using negative index values produced incorrect results.gh-93162: Add the ability for
logging.config.dictConfig()
to usefully configureQueueHandler
andQueueListener
as a pair, and addlogging.getHandlerByName()
andlogging.getHandlerNames()
APIs to allow access to handlers by name.gh-93243: The
smtpd
module was removed per the schedule in PEP 594.gh-92886: Replace
assert
statements withraise AssertionError()
inBaseHandler
so that the tested behaviour is maintained running with optimizations(-O)
.gh-90155: Fix broken
asyncio.Semaphore
when acquire is cancelled.gh-90817: The
locale.resetlocale()
function is deprecated and will be removed in Python 3.13. Uselocale.setlocale(locale.LC_ALL, "")
instead. Patch by Victor Stinner.gh-91513: Added
taskName
attribute tologging
module for use withasyncio
tasks.gh-74696:
shutil.make_archive()
no longer temporarily changes the current working directory during creation of standard.zip
or tar archives.gh-92728: The
re.template()
function and the correspondingre.TEMPLATE
andre.T
flags are restored after they were removed in 3.11.0b1, but they are now deprecated, so they might be removed from Python 3.13.gh-93033: Search in some strings (platform dependent i.e [U+0xFFFF, U+0x0100] on Windows or [U+0xFFFFFFFF, U+0x00010000] on Linux 64-bit) are now up to 10 times faster.
gh-89973: Fix
re.error
raised infnmatch
if the pattern contains a character range with upper bound lower than lower bound (e.g.[c-a]
). Now such ranges are interpreted as empty ranges.gh-93044: No longer convert the database argument of
sqlite3.connect()
to bytes before passing it to the factory.gh-93010: In a very special case, the email package tried to append the nonexistent
InvalidHeaderError
to the defect list. It should have beenInvalidHeaderDefect
.gh-92986: Fix
ast.unparse()
whenImportFrom.level
is Nonegh-92932: Now
dis()
andget_instructions()
handle operand values for instructions prefixed byEXTENDED_ARG_QUICK
. Patch by Sam Gross and Dong-hee Na.gh-92675: Fix
venv.ensure_directories()
to acceptpathlib.Path
arguments in addition tostr
paths. Patch by David Foster.gh-87901: Removed the
encoding
argument fromos.popen()
that was added in 3.11b1.gh-91922: Fix function
sqlite.connect()
and thesqlite.Connection
constructor on non-UTF-8 locales. Also, they now support bytes paths non-decodable with the current FS encoding.gh-92869: Added
c_time_t
toctypes
, which has the same size as thetime_t
type in C.gh-92839: Fixed crash resulting from calling bisect.insort() or bisect.insort_left() with the key argument not equal to None.
gh-90473:
subprocess
now fails early on Emscripten and WASI platforms to work around missingos.pipe()
on WASI.gh-89325: Removed many old deprecated
unittest
features:TestCase
method aliases, undocumented and brokenTestCase
methodassertDictContainsSubset
, undocumentedTestLoader.loadTestsFromModule
parameter use_load_tests, and an underscored alias of theTextTestResult
class.gh-92734: Allow multi-element reprs emitted by
reprlib
to be pretty-printed using configurable indentation.gh-92671: Fixed
ast.unparse()
for empty tuples in the assignment target context.gh-91581:
utcfromtimestamp()
no longer attempts to resolvefold
in the pure Python implementation, since the fold is never 1 in UTC. In addition to being slightly faster in the common case, this also prevents some errors when the timestamp is close todatetime.min
. Patch by Paul Ganssle.gh-86388: Removed randrange() functionality deprecated since Python 3.10. Formerly, randrange(10.0) losslessly converted to randrange(10). Now, it raises a TypeError. Also, the exception raised for non-integral values such as randrange(10.5) or randrange(“10”) has been changed from ValueError to TypeError.
gh-90385: Add
pathlib.Path.walk()
as an alternative toos.walk()
.gh-92550: Fix
pathlib.Path.rglob()
for empty pattern.gh-92591: Allow
logging
filters to return alogging.LogRecord
instance so that filters attached tologging.Handler
s can enrich records without side effects on other handlers.gh-92445: Fix a bug in
argparse
wherenargs="*"
would raise an error instead of returning an empty list when 0 arguments were supplied if choice was also defined inparser.add_argument
.gh-92547: Remove undocumented
sqlite3
features deprecated in Python 3.10:sqlite3.enable_shared_cache()
sqlite3.OptimizedUnicode
Patch by Erlend E. Aasland.
gh-92530: Fix an issue that occurred after interrupting
threading.Condition.notify()
.gh-92531: The statistics.median_grouped() function now always return a float. Formerly, it did not convert the input type when for sequences of length one.
gh-84131: The
pathlib.Path
deprecated methodlink_to
has been removed. Use 3.10’shardlink_to()
method instead as its semantics are consistent with that ofsymlink_to()
.gh-89336: Removed
configparser
module APIs: theSafeConfigParser
class alias, theParsingError.filename
property and parameter, and theConfigParser.readfp
method, all of which were deprecated since Python 3.2.gh-92391: Add
__class_getitem__()
tocsv.DictReader
andcsv.DictWriter
, allowing them to be parameterized at runtime. Patch by Marc Mueller.gh-91968: Add
SO_RTABLE
andSO_USER_COOKIE
constants tosocket
.gh-91810:
ElementTree
methodwrite()
and functiontostring()
now use the text file’s encoding («UTF-8» if not available) instead of locale encoding in XML declaration whenencoding="unicode"
is specified.gh-81790:
os.path.splitdrive()
now understands DOS device paths with UNC links (beginning\\?\UNC\
). Contributed by Barney Gale.gh-91760: Apply more strict rules for numerical group references and group names in regular expressions. Only sequence of ASCII digits is now accepted as a numerical reference. The group name in bytes patterns and replacement strings can now only contain ASCII letters and digits and underscore.
gh-90622: Worker processes for
concurrent.futures.ProcessPoolExecutor
are no longer spawned on demand (a feature added in 3.9) when the multiprocessing context start method is"fork"
as that can lead to deadlocks in the child processes due to a fork happening while threads are running.gh-91577: Move imports in
SharedMemory
methods to module level so that they can be executed late in python finalization.gh-91581: Remove an unhandled error case in the C implementation of calls to
datetime.fromtimestamp
with no time zone (i.e. getting a local time from an epoch timestamp). This should have no user-facing effect other than giving a possibly more accurate error message when called with timestamps that fall on 10000-01-01 in the local time. Patch by Paul Ganssle.gh-91539: Improve performance of
urllib.request.getproxies_environment
when there are many environment variablesgh-91524: Speed up the regular expression substitution (functions
re.sub()
andre.subn()
and correspondingre.Pattern
methods) for replacement strings containing group references by 2–3 times.gh-91447: Fix findtext in the xml module to only give an empty string when the text attribute is set to None.
gh-91456: Deprecate current default auto() behavior: In 3.13 the default will be for for auto() to always return the largest member value incremented by 1, and to raise if incompatible value types are used.
bpo-47231: Fixed an issue with inconsistent trailing slashes in tarfile longname directories.
bpo-39064:
zipfile.ZipFile
now raiseszipfile.BadZipFile
instead ofValueError
when reading a corrupt zip file in which the central directory offset is negative.bpo-41287: Fix handling of the
doc
argument in subclasses ofproperty()
.gh-90005:
ctypes
dependencylibffi
is now detected withpkg-config
.bpo-32547: The constructors for
DictWriter
andDictReader
now coerce thefieldnames
argument to alist
if it is an iterator.bpo-35540: Fix
dataclasses.asdict()
crash whencollections.defaultdict
is present in the attributes.bpo-47063: Add an index_pages parameter to support using non-default index page names.
bpo-46951: Order the contents of zipapp archives, to make builds more reproducible.
bpo-42777: Implement
pathlib.Path.is_mount()
for Windows paths.bpo-46755: In
QueueHandler
, clearstack_info
fromLogRecord
to prevent stack trace from being written twice.bpo-45393: Fix the formatting for
await x
andnot x
in the operator precedence table when using thehelp()
system.bpo-46642: Improve error message when trying to subclass an instance of
typing.TypeVar
,typing.ParamSpec
,typing.TypeVarTuple
, etc. Based on patch by Gregory Beauregard.bpo-46364: Restrict use of sockets instead of pipes for stdin of subprocesses created by
asyncio
to AIX platform only.bpo-28249: Set
doctest.DocTest.lineno
toNone
when object does not have__doc__
.bpo-46197: Fix
ensurepip
environment isolation for subprocess runningpip
.bpo-45924: Fix
asyncio
incorrect traceback when future’s exception is raised multiple times. Patch by Kumar Aditya.bpo-45046: Add support of context managers in
unittest
: methodsenterContext()
andenterClassContext()
of classTestCase
, methodenterAsyncContext()
of classIsolatedAsyncioTestCase
and functionunittest.enterModuleContext()
.bpo-44173: Enable fast seeking of uncompressed unencrypted
zipfile.ZipExtFile
bpo-42627: Fix incorrect parsing of Windows registry proxy settings
bpo-42047: Add
threading.get_native_id()
support for DragonFly BSD. Patch by David Carlier.bpo-14243: The
tempfile.NamedTemporaryFile
function has a new optional parameter delete_on_closebpo-41246: Give the same callback function for when the overlapped operation is done to the functions
recv
,recv_into
,recvfrom
,sendto
,send
andsendfile
insideIocpProactor
.bpo-39264: Fixed
collections.UserDict.get()
to not call__missing__()
when a value is not found. This matches the behavior ofdict
. Patch by Bar Harel.bpo-38693:
importlib
now uses f-strings internally instead ofstr.format
.bpo-38267: Add timeout parameter to
asyncio.loop.shutdown_default_executor()
. The default value isNone
, which means the executor will be given an unlimited amount of time. When called fromasyncio.Runner
orasyncio.run()
, the default timeout is 5 minutes.bpo-34828:
sqlite3.Connection.iterdump()
now handles databases that useAUTOINCREMENT
in one or more tables.bpo-32990: Support reading wave files with the
WAVE_FORMAT_EXTENSIBLE
format in thewave
module.bpo-26253: Allow adjustable compression level for tarfile streams in
tarfile.open()
.
Documentation¶
gh-85525: Remove extra row
gh-86404: Deprecated tools
make suspicious
andrstlint.py
are now removed. They have been replaced by spinx-lint.gh-97741: Fix
!
in c domain ref target syntax via aconf.py
patch, so it works as intended to disable ref target resolution.gh-96432: Fraction literals now support whitespace around the forward slash,
Fraction('2 / 3')
.gh-96098: Improve discoverability of the higher level concurrent.futures module by providing clearer links from the lower level threading and multiprocessing modules.
gh-95957: What’s New 3.11 now has instructions for how to provide compiler and linker flags for Tcl/Tk and OpenSSL on RHEL 7 and CentOS 7.
gh-95588: Clarified the conflicting advice given in the
ast
documentation aboutast.literal_eval()
being «safe» for use on untrusted input while at the same time warning that it can crash the process. The latter statement is true and is deemed unfixable without a large amount of work unsuitable for a bugfix. So we keep the warning and no longer claim thatliteral_eval
is safe.gh-91207: Fix stylesheet not working in Windows CHM htmlhelp docs and add warning that they are deprecated. Contributed by C.A.M. Gerlach.
gh-95454: Replaced incorrectly written true/false values in documentiation. Patch by Robert O’Shea
gh-95451: Update library documentation with availability information on WebAssembly platforms
wasm32-emscripten
andwasm32-wasi
.gh-95415: Use consistent syntax for platform availability. The directive now supports a content body and emits a warning when it encounters an unknown platform.
gh-94321: Document the PEP 246 style protocol type
sqlite3.PrepareProtocol
.gh-86128: Document a limitation in ThreadPoolExecutor where its exit handler is executed before any handlers in atexit.
gh-61162: Clarify
sqlite3
behavior when Como usar la conexión con un administrador de contexto.gh-87260: Align
sqlite3
argument specs with the actual implementation.gh-86986: The minimum Sphinx version required to build the documentation is now 3.2.
gh-88831: Augmented documentation of asyncio.create_task(). Clarified the need to keep strong references to tasks and added a code snippet detailing how to do this.
gh-86438: Clarify that
-W
andPYTHONWARNINGS
are matched literally and case-insensitively, rather than as regular expressions, inwarnings
.gh-93031: Update tutorial introduction output to use 3.10+ SyntaxError invalid range.
gh-92240: Added release dates for «What’s New in Python 3.X» for 3.0, 3.1, 3.2, 3.8 and 3.10
bpo-47161: Document that
pathlib.PurePath
does not collapse initial double slashes because they denote UNC paths.bpo-40838: Document that
inspect.getdoc()
,inspect.getmodule()
, andinspect.getsourcefile()
might returnNone
.bpo-43689: The
Differ
documentation now also mentions other whitespace characters, which make it harder to understand the diff output.bpo-38056: Overhaul the Manejadores de errores documentation in
codecs
.bpo-13553: Document tkinter.Tk args.
Tests¶
gh-95027: On Windows, when the Python test suite is run with the
-jN
option, the ANSI code page is now used as the encoding for the stdout temporary file, rather than using UTF-8 which can lead to decoding errors. Patch by Victor Stinner.gh-96624: Fixed the failure of repeated runs of
test.test_unittest
caused by side effects intest_dotted_but_module_not_loaded
.gh-95243: Mitigate the inherent race condition from using find_unused_port() in testSockName() by trying to find an unused port a few times before failing. Patch by Ross Burton.
gh-95573: Lib/test/test_asyncio/test_ssl.py exposed a bug in the macOS kernel where intense concurrent load on non-blocking sockets occasionally causes
errno.ENOBUFS
(«No buffer space available») to be emitted. FB11063974 filed with Apple, in the mean time as a workaround buffer size used in tests on macOS is decreased to avoid intermittent failures. Patch by Fantix King.gh-95280: Fix problem with
test_ssl
test_get_ciphers
on systems that require perfect forward secrecy (PFS) ciphers.gh-95212: Make multiprocessing test case
test_shared_memory_recreate
parallel-safe.gh-95218: Move tests for importlib.resources into test_importlib.resources.
gh-93963: Updated tests to use preferred location for
importlib.resources
ABCs.gh-94675: Add a regression test for
re
exponentional slowdown when using rjsmin.gh-91330: Added more tests for
dataclasses
to cover behavior with data descriptor-based fields.gh-94208:
test_ssl
is now checking for supported TLS version and protocols in more tests.gh-94315: Tests now check for DAC override capability instead of relying on
os.geteuid()
.gh-54781: Rename test_tk to test_tkinter, and rename test_ttk_guionly to test_ttk. Patch by Victor Stinner.
gh-93839: Move
Lib/ctypes/test/
toLib/test/test_ctypes/
. Patch by Victor Stinner.gh-93951: In test_bdb.StateTestCase.test_skip, avoid including auxiliary importers.
gh-93957: Provide nicer error reporting from subprocesses in test_venv.EnsurePipTest.test_with_pip.
gh-93884: Add test cases for
PyNumber_ToBase()
that take a large number or a non-int object as parameter.gh-93852: test_asyncio, test_logging, test_socket and test_socketserver now create AF_UNIX domains in the current directory to no longer fail with
OSError("AF_UNIX path too long")
if the temporary directory (theTMPDIR
environment variable) is too long. Patch by Victor Stinner.gh-93353: regrtest now checks if a test leaks temporary files or directories if run with -jN option. Patch by Victor Stinner.
gh-84461:
run_tests.py
now handles cross compiling env vars correctly and passHOSTRUNNER
to regression tests.gh-93616:
test_modulefinder
now creates a temporary directory inModuleFinderTest.setUp()
instead of module scope.gh-93575: Fix issue with test_unicode test_raiseMemError. The test case now use
test.support.calcobjsize
to calculate size of PyUnicode structs.sys.getsizeof()
may return different size when string has UTF-8 memory.gh-90473: WASI does not have a
chmod(2)
syscall.os.chmod()
is now a dummy function on WASI. Skip all tests that depend on workingos.chmod()
.gh-90473: Skip tests on WASI that require symlinks with absolute paths.
gh-57539: Increase calendar test coverage for
calendar.LocaleTextCalendar.formatweekday()
.gh-90473: Skip symlink tests on WASI. wasmtime uses
openat2(2)
withRESOLVE_BENEATH
flag, which prevents symlinks with absolute paths.gh-89858: Fix
test_embed
for out-of-tree builds. Patch by Kumar Aditya.gh-92886: Fixing tests that fail when running with optimizations (
-O
) intest_imaplib.py
.gh-92886: Fixing tests that fail when running with optimizations (
-O
) intest_zipimport.py
gh-92886: Fixing tests that fail when running with optimizations (
-O
) intest_py_compile.py
gh-92886: Fixing tests that fail when running with optimizations (
-O
) intest_sys_settrace.py
.gh-92886: Fixing tests that fail when running with optimizations (
-O
) in_test_multiprocessing.py
gh-92670: Skip
test_shutil.TestCopy.test_copyfile_nonexistent_dir
test on AIX as the test uses a trailing slash to force the OS consider the path as a directory, but on AIX the trailing slash has no effect and is considered as a file.gh-92514: Remove unused
test.support.BasicTestRunner
. Patch by Jelle Zijlstra.bpo-47016: Create a GitHub Actions workflow for verifying bundled pip and setuptools. Patch by Illia Volochii and Adam Turner.
Build¶
gh-96761: Fix the build process of clang compiler for _bootstrap_python if LTO optimization is applied. Patch by Matthias Görgens and Dong-hee Na.
gh-96883:
wasm32-emscripten
builds for browsers now includeconcurrent.futures
forasyncio
andunittest.mock
.gh-85936: CPython now uses the ThinLTO option as the default policy if the Clang compiler accepts the flag. Patch by Dong-hee Na.
gh-96729: Ensure that Windows releases built with
Tools\msi\buildrelease.bat
are upgradable to and from official Python releases.gh-96269: Shared module targets now depend on new
MODULE_DEPS
variable, which includesEXPORTSYMS
. This fixes a build order issue on unsupported AIX platform.gh-84461:
wasm32-emscripten
platform no longer buildsresource
module,getresuid()
,getresgid()
, and their setters. The APIs are stubs and not functional.gh-95973: Add a new
--with-dsymutil
configure option to link debug information in macOS. Patch by Pablo Galindo.gh-90536: Use the BOLT post-link optimizer to improve performance, particularly on medium-to-large applications.
gh-93744: Remove the
configure --with-cxx-main
build option: it didn’t work for many years. Remove theMAINCC
variable fromconfigure
andMakefile
. Patch by Victor Stinner.gh-94801: Fix a regression in
configure
script that caused some header checks to ignore customCPPFLAGS
. The regression was introduced in gh-94802.gh-95145: wasm32-wasi builds no longer depend on WASIX’s pthread stubs. Python now has its own stubbed pthread API.
gh-95174: Python now detects missing
dup
function in WASI and works around some missingerrno
,select
, andsocket
constants.gh-95174: Python now skips missing
socket
functions and methods on WASI. WASI can only create sockets from existing fd / accept and has no netdb.gh-95085: Platforms
wasm32-unknown-emscripten
andwasm32-unknown-wasi
have been promoted to PEP 11 tier 3 platform support.gh-94847: Fixed
_decimal
module build issue on GCC when compiling with LTO and pydebug. Debug builds no longer force inlining of functions.gh-94841: Fix the possible performance regression of
PyObject_Free()
compiled with MSVC version 1932.gh-94801:
configure
now uses custom flags likeZLIB_CFLAGS
andZLIB_LIBS
when searching for headers and libraries.gh-94773:
deepfreeze.py
now supports code object with frozensets that contain incompatible, unsortable types.gh-94682: Build and test with OpenSSL 1.1.1q
gh-90005: Dependencies of
readline
andcurses
module are now detected inconfigure
script withpkg-config
. Onlyncurses
/ncursesw
are detected automatically. The oldcurses
library is not configured automatically. Workaround for missingtermcap
ortinfo
library has been removed.gh-90005: Fix building
_ctypes
extension withoutpkg-config
.gh-90005:
_dbm
module dependencies are now detected by configure.gh-94404:
makesetup
now works around an issue with sed on macOS and uses correct CFLAGS for object files that end up in a shared extension. Module CFLAGS are used before PY_STDMODULE_CFLAGS to avoid clashes with system headers.gh-93939: C extension modules are now built by
configure
andmake
instead ofdistutils
andsetup.py
.gh-93939: The
2to3
,idle
, andpydoc
scripts are now generated and installed byMakefile
instead ofsetup.py
.gh-94280: Updated pegen regeneration script on Windows to find and use Python 3.9 or higher. Prior to this, pegen regeneration already required 3.9 or higher, but the script may have used lower versions of Python.
gh-93584: Address race condition in
Makefile
when installing a PGO build. Alltest
andinstall
targets now depend onall
target.gh-93491:
configure
now detects and reports PEP 11 support tiers.gh-69093: Fix
Modules/Setup.stdlib.in
rule for_sqlite3
extension.gh-93207:
va_start()
with two parameters, likeva_start(args, format),
is now required to build Python.va_start()
is no longer called with a single parameter. Patch by Kumar Aditya.gh-93202: Python now always use the
%zu
and%zd
printf formats to format asize_t
orPy_ssize_t
number. Building Python 3.12 requires a C11 compiler, so these printf formats are now always supported. Patch by Victor Stinner.gh-90473: Disable pymalloc and increase stack size on
wasm32-wasi
.bpo-34449: Drop invalid compiler switch
-fPIC
for HP aCC on HP-UX. Patch by Michael Osipov.
Windows¶
gh-98360: Fixes
multiprocessing
spawning child processes on Windows from a virtual environment to ensure that child processes that also usemultiprocessing
to spawn more children will recognize that they are in a virtual environment.gh-98414: Fix
py.exe
launcher handling of-V:<company>/
option when default preferences have been set in environment variables or configuration files.gh-97728: Fix possible crashes caused by the use of uninitialized variables when pass invalid arguments in
os.system()
on Windows and in Windows-specific modules (likewinreg
).gh-90989: Made Lanzador de Python para Windows install per-user by default (unless an all users install already exists), and clarify some text in the installer.
gh-97649: The
Tools
directory is no longer installed on Windowsgh-96965: Update libffi to 3.4.3
gh-96559: Fixes the Windows launcher not using the compatible interpretation of default tags found in configuration files when no tag was passed to the command.
gh-94781: Fix
pcbuild.proj
to clean previous instances of output files inPython\deepfreeze
andPython\frozen_modules
directories on Windows. Patch by Charlie Zhao.gh-89545: Updates
platform
code getting the Windows version to use native Windows Management Instrumentation (WMI) queries to determine OS version, type, and architecture.gh-95733: Make certain requirements of the Windows Store package optional to allow installing on earlier updates of Windows.
gh-95656: Enable the
enable_load_extension()
sqlite3
API.gh-95587: Fixes some issues where the Windows installer would incorrectly detect certain features of an existing install when upgrading.
gh-94399: Restores the behaviour of Lanzador de Python para Windows for
/usr/bin/env
shebang lines, which will now searchPATH
for an executable matching the given command. If none is found, the usual search process is used.gh-95445: Fixes the unsuccessful removal of the HTML document directory when uninstalling with Windows msi.
gh-95359: Fix Lanzador de Python para Windows handling of
py.ini
commands (it was incorrectly expecting apy_
prefix on keys) and crashes when reading per-user configuration file.gh-95285: Fix Lanzador de Python para Windows handling of command lines where it is only passed a short executable name.
gh-90844: Allow virtual environments to correctly launch when they have spaces in the path.
gh-94772: Fix incorrect handling of shebang lines in py.exe launcher
gh-94018:
zipfile
will now remove trailing spaces from path components when extracting files on Windows.gh-93824: Drag and drop of files onto Python files in Windows Explorer has been enabled for Windows ARM64.
gh-43414:
os.get_terminal_size()
now attempts to read the size from any provided handle, rather than only supporting file descriptors 0, 1 and 2.gh-92817: Ensures that
py.exe
will prefer an active virtual environment over default tags specified with environment variables or through apy.ini
file.gh-92984: Explicitly disable incremental linking for non-Debug builds
gh-92841:
asyncio
no longer throwsRuntimeError: Event loop is closed
on interpreter exit after asynchronous socket activity. Patch by Oleg Iarygin.bpo-46907: Update Windows installer to use SQLite 3.38.4.
gh-91061: Accept os.PathLike for the argument to winsound.PlaySound
bpo-42658: Support native Windows case-insensitive path comparisons by using
LCMapStringEx
instead ofstr.lower()
inntpath.normcase()
. AddLCMapStringEx
to the_winapi
module.bpo-38704: Prevent installation on unsupported Windows versions.
macOS¶
gh-97897: The macOS 13 SDK includes support for the
mkfifoat
andmknodat
system calls. Using thedir_fd
option with eitheros.mkfifo()
oros.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: 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: Document handling of extensions in Save As dialogs.
gh-95191: Include prompts when saving Shell (interactive input and output).
gh-95511: Fix the Shell context menu copy-with-prompts bug of copying an extra line when one selects whole lines.
gh-95471: In the Edit menu, move
Select All
and add a new separator.gh-95411: Enable using IDLE’s module browser with .pyw files.
gh-89610: Add .pyi as a recognized extension for IDLE on macOS. This allows opening stub files by double clicking on them in the Finder.
Tools/Demos¶
gh-68686: Remove ptags and eptags scripts.
gh-97681: Remove the
Tools/demo/
directory which contained old demo scripts. A copy can be found in the old-demos project. Patch by Victor Stinner.gh-97669: Remove outdated example scripts of the
Tools/scripts/
directory. A copy can be found in the old-demos project. Patch by Victor Stinner.gh-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: The new tool
Tools/wasm/wasm_builder.py
automates configure, compile, and test steps for building CPython on WebAssembly platforms.gh-95731: Fix handling of module docstrings in
Tools/i18n/pygettext.py
.gh-93939: Add script
Tools/scripts/check_modules.py
to check and validate builtin and shared extension modules. The script also handlesModules/Setup
and will eventually replacesetup.py
.gh-94538: Fix Argument Clinic output to custom file destinations. Patch by Erlend E. Aasland.
gh-94430: Allow parameters named
module
andself
with custom C names in Argument Clinic. Patch by Erlend E. Aaslandgh-86087: The
Tools/scripts/parseentities.py
script used to parse HTML4 entities has been removed.
C API¶
gh-98393: The
PyUnicode_FSDecoder()
function no longer accepts bytes-like paths, likebytearray
andmemoryview
types: only the exactbytes
type is accepted for bytes strings. Patch by Victor Stinner.gh-91051: Add
PyType_Watch()
and related APIs to allow callbacks onPyType_Modified()
.gh-95756: Lazily create and cache
co_
attributes for better performance for code getters.gh-96512: Configuration for the integer string conversion length limitation now lives in the PyConfig C API struct.
gh-95589: Extensions classes that set
tp_dictoffset
andtp_weaklistoffset
lose the support for multiple inheritance, but are now safe. Extension classes should usePy_TPFLAGS_MANAGED_DICT
andPy_TPFLAGS_MANAGED_WEAKREF
instead.gh-95781: An unrecognized format character in
PyUnicode_FromFormat()
andPyUnicode_FromFormatV()
now sets aSystemError
. 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: Restore the 3.10 behavior for multiple inheritance of C extension classes that store their dictionary at the end of the struct.
gh-92678: Support C extensions using managed dictionaries by setting the
Py_TPFLAGS_MANAGED_DICT
flag.gh-93274: API for implementing vectorcall (
Py_TPFLAGS_HAVE_VECTORCALL
,PyVectorcall_NARGS()
andPyVectorcall_Call()
) was added to the limited API and stable ABI.gh-95504: Fix sign placement when specifying width or precision in
PyUnicode_FromFormat()
andPyUnicode_FromFormatV()
. Patch by Philip Georgi.gh-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 theimmutable
flag). Mutable types that do not overridetp_call
now inherit thePy_TPFLAGS_HAVE_VECTORCALL
flag.gh-95388: Creating
immutable types
with mutable bases is deprecated and is planned to be disabled in Python 3.14.gh-92678: Adds unstable C-API functions
_PyObject_VisitManagedDict
and_PyObject_ClearManagedDict
to allow C extensions to allow the VM to manage their object’s dictionaries.gh-94936: Added
PyCode_GetVarnames()
,PyCode_GetCellvars()
andPyCode_GetFreevars()
for accessingco_varnames
,co_cellvars
andco_freevars
respectively via the C API.gh-94930: Fix
SystemError
raised whenPyArg_ParseTupleAndKeywords()
is used with#
in(...)
but withoutPY_SSIZE_T_CLEAN
defined.gh-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 forg++
.gh-93937: The following frame functions and type are now directly available with
#include <Python.h>
, it’s no longer needed to add#include <frameobject.h>
:Patch by Victor Stinner.
gh-91321: Fix the compatibility of the Python C API with C++ older than C++11. Patch by Victor Stinner.
gh-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 Galindogh-89546:
PyType_FromMetaclass()
(and otherPyType_From*
functions) now check that offsets and the base class’stp_basicsize
fit in the new class’stp_basicsize
.gh-93503: Add two new public functions to the public C-API,
PyEval_SetProfileAllThreads()
andPyEval_SetTraceAllThreads()
, that allow to set tracing and profiling functions in all running threads in addition to the calling one. Also, two analogous functions to thethreading
module (threading.setprofile_all_threads()
andthreading.settrace_all_threads()
) that allow to do the same from Python. Patch by Pablo Galindogh-93442: Add C++ overloads for _Py_CAST_impl() to handle 0/NULL. This will allow C++ extensions that pass 0 or NULL to macros using _Py_CAST() to continue to compile.
gh-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: Fix C++ compiler warnings when casting function arguments to
PyObject*
. Patch by Serge Guelton.gh-93103: Deprecate global configuration variables, like
Py_IgnoreEnvironmentFlag
, in the documentation: thePy_InitializeFromConfig()
API should be instead. Patch by Victor Stinner.gh-77782: Deprecate global configuration variable like
Py_IgnoreEnvironmentFlag
: thePy_InitializeFromConfig()
API should be instead. Patch by Victor Stinner.gh-92913: Ensures changes to
PyConfig.module_search_paths
are ignored unlessPyConfig.module_search_paths_set
is setgh-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: Remove the
token.h
header file. There was never any public tokenizer C API. Thetoken.h
header file was only designed to be used by Python internals. Patch by Victor Stinner.gh-92536: Remove legacy Unicode APIs based on
Py_UNICODE*
.gh-85858: Remove the
PyUnicode_InternImmortal()
function and theSSTATE_INTERNED_IMMORTAL
macro. Patch by Victor Stinner.gh-92193: Add new function
PyFunction_SetVectorcall()
to the C API which sets the vectorcall field of a givenPyFunctionObject
.Warning: extensions using this API must preserve the behavior of the unaltered function!
gh-59121: Fixed an assert that prevented
PyRun_InteractiveOne
from providing tracebacks when parsing from the provided FD.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
Security¶
gh-57684: Add the
-P
command line option and thePYTHONSAFEPATH
environment variable to not prepend a potentially unsafe path tosys.path
. Patch by Victor Stinner.
Core and Builtins¶
gh-89519: Chaining classmethod descriptors (introduced in 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:
pymain_run_python()
now importsreadline
andrlcompleter
before sys.path is extended to include the current working directory of an interactive interpreter. Non-interactive interpreters are not affected.bpo-43857: Improve the
AttributeError
message when deleting a missing attribute. Patch by Géry Ogam.gh-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: 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: Disable frozen modules in debug builds. Patch by Kumar Aditya.
gh-92114: Improve error message when subscript a type with
__class_getitem__
set toNone
.gh-92112: Fix crash triggered by an evil custom
mro()
on a metaclass.gh-92063: The
PRECALL_METHOD_DESCRIPTOR_FAST_WITH_KEYWORDS
instruction now ensures methods are called only on objects of the correct type.gh-92031: Deoptimize statically allocated code objects during
Py_FINALIZE()
so that future_PyCode_Quicken
calls always start with unquickened code.gh-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: The interpreter can now autocomplete soft keywords, as of now
match
,case
, and_
(wildcard pattern) from PEP 634.gh-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: Fix an issue where specialized opcodes with extended arguments could produce incorrect tracing output or lead to assertion failures.
gh-91603: Speed up
types.UnionType
instantiation. Based on patch provided by Yurii Karabas.gh-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: Fix a minor memory leak at exit: release the memory of the
generic_alias_iterator
type. Patch by Dong-hee Na.gh-81548: Octal escapes with value larger than
0o377
now produce aDeprecationWarning
. In a future Python version they will be aSyntaxWarning
and eventually aSyntaxError
.bpo-43950: Use a single compact table for line starts, ends and column offsets. Reduces memory consumption for location info by half
gh-91102: Use Argument Clinic for
EncodingMap
. Patch by Oleg Iarygin.gh-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: Speed up
isinstance()
andissubclass()
checks fortypes.UnionType
. Patch by Yurii Karabas.gh-91625: Fixed a bug in which adaptive opcodes ignored any preceding
EXTENDED_ARG
s on specialization failure.gh-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: Speed up iteration of ascii strings by 50%. Patch by Kumar Aditya.
gh-89279: Improve interpreter performance on Windows by inlining a few specific macros.
gh-91502: Add a new
_PyFrame_IsEntryFrame()
API function, to check if aPyFrameObject
is an entry frame. Patch by Pablo Galindo.gh-91266: Refactor the
bytearray
strip methodsstrip
,lstrip
andrstrip
to use a common implementation.gh-91479: Replaced the
__note__
field ofBaseException
(added in an earlier version of 3.11) with the final design of PEP 678. Namely,BaseException
gets anadd_note()
method, and its__notes__
field is created when necessary.gh-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: 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: Fixed an uninitialized bool value in the traceback printing code path that was introduced by the initial bpo-45292 exception groups work.
gh-91421: Fix a potential integer overflow in _Py_DecodeUTF8Ex.
gh-91428: Add
static const char *const _PyOpcode_OpName[256] = {...};
toopcode.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: Make
POP_JUMP_IF_TRUE
,POP_JUMP_IF_FALSE
,POP_JUMP_IF_NONE
andPOP_JUMP_IF_NOT_NONE
virtual, mapping to new relative jump opcodes.bpo-45317: Add internal documentation explaining design of new (for 3.11) frame stack.
bpo-47197: ctypes used to mishandle
void
return types, so that for instance a function declared likectypes.CFUNCTYPE(None, ctypes.c_int)
would be called with signatureint f(int)
instead ofvoid 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: Make opcodes
JUMP_IF_TRUE_OR_POP
andJUMP_IF_FALSE_OR_POP
relative rather than absolute.bpo-47177: Replace the
f_lasti
member of the internal_PyInterpreterFrame
structure with aprev_instr
pointer, which reduces overhead in the main interpreter loop. Thef_lasti
attribute of Python-layer frame objects is preserved for backward-compatibility.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: 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
, andtypes.GenericAlias
.The functions affected are 24 methods in
ctypes
.Patch by Oleg Iarygin.
bpo-46942: Use Argument Clinic for the
types.MethodType
constructor. Patch by Oleg Iarygin.bpo-46764: Fix wrapping bound methods with @classmethod
bpo-43464: Optimize
set.intersection()
for non-set arguments.bpo-46721: Optimize
set.issuperset()
for non-set argument.bpo-46509: Add type-specialized versions of the
Py_DECREF()
, and use them forfloat
,int
,str
,bool
, andNone
to avoid pointer-chasing at runtime where types are known at C compile time.bpo-46045: Do not use POSIX semaphores on NetBSD
bpo-36819: Fix crashes in built-in encoders with error handlers that return position less or equal than the starting position of non-encodable characters.
bpo-34093:
marshal.dumps()
usesFLAG_REF
for all interned strings. This makes output more deterministic and helps reproducible build.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.
Library¶
gh-87901: Add the encoding parameter to
os.popen()
.gh-90997: Fix an issue where
dis
utilities may interpret populated inline cache entries as valid instructions.gh-92332: Deprecate
typing.Text
(removal of the class is currently not planned). Patch by Alex Waygood.Deprecate nested classes in enum definitions becoming members – in 3.13 they will be normal classes; add
member
andnonmember
functions to allow control over results now.gh-92356: Fixed a performance regression in ctypes function calls.
gh-90997: Show the actual named values stored in inline caches when
show_caches=True
is passed todis
utilities.gh-92301: Prefer
close_range()
to iterating over procfs for file descriptor closing insubprocess
for better performance.gh-67248: Sort the miscellaneous topics in Cmd.do_help()
gh-92210: Port
socket.__init__
to Argument Clinic. Patch by Cinder.gh-80010: Add support for generalized ISO 8601 parsing to
datetime.datetime.fromisoformat()
,datetime.date.fromisoformat()
anddatetime.time.fromisoformat()
. Patch by Paul Ganssle.gh-92118: Fix a 3.11 regression in
contextmanager()
, which caused it to propagate exceptions with incorrect tracebacks.gh-90887: Adding
COPYFILE_STAT
,COPYFILE_ACL
andCOPYFILE_XATTR
constants foros.fcopyfile()
available in macOs.gh-91215: For @dataclass, add weakref_slot. Default is False. If True, and if slots=True, add a slot named «__weakref__», which will allow instances to be weakref’d. Contributed by Eric V. Smith
gh-85984: New function os.login_tty() for Unix.
gh-92128: Add
__class_getitem__()
tologging.LoggerAdapter
andlogging.StreamHandler
, allowing them to be parameterized at runtime. Patch by Alex Waygood.gh-92049: Forbid pickling constants
re._constants.SUCCESS
etc. Previously, pickling did not fail, but the result could not be unpickled.gh-92062:
inspect.Parameter
now raisesValueError
ifname
is a keyword, in addition to the existing check that it is an identifier.gh-87390: Add an
__unpacked__
attribute totypes.GenericAlias
. Patch by Jelle Zijlstra.gh-88089: Add support for generic
typing.NamedTuple
.gh-91996: New http.HTTPMethod enum to represent all the available HTTP request methods in a convenient way
gh-91984: Modified test strings in test_argparse.py to not contain trailing spaces before end of line.
gh-91952: Add
encoding="locale"
support toTextIOWrapper.reconfigure()
.gh-91954: Add encoding and errors arguments to
subprocess.getoutput()
andsubprocess.getstatusoutput()
.bpo-47029: Always close the read end of the pipe used by
multiprocessing.Queue
after the last write of buffered data to the write end of the pipe to avoidBrokenPipeError
at garbage collection and atmultiprocessing.Queue.close()
calls. Patch by Géry Ogam.gh-91928: Add
datetime.UTC
alias fordatetime.timezone.utc
.Patch by Kabir Kwatra.
gh-68966: The
mailcap
module is now deprecated and will be removed in Python 3.13. See PEP 594 for the rationale and themimetypes
module for an alternative. Patch by Victor Stinner.gh-91401: Provide a way to disable
subprocess
use ofvfork()
just in case it is ever needed and document the existing mechanism forposix_spawn()
.gh-64783: Fix
signal.NSIG
value on FreeBSD to accept signal numbers greater than 32, likesignal.SIGRTMIN
andsignal.SIGRTMAX
. Patch by Victor Stinner.gh-91910: Add missing f prefix to f-strings in error messages from the
multiprocessing
andasyncio
modules.gh-91860: Add
typing.dataclass_transform()
, implementing PEP 681. Patch by Jelle Zijlstra.gh-91832: Add
required
attribute toargparse.Action
repr output.gh-91827: In the
tkinter
module add methodinfo_patchlevel()
which returns the exact version of the Tcl library as a named tuple similar tosys.version_info
.gh-84461: Add
--enable-wasm-pthreads
to enable pthreads support for WASM builds.Emscripten/node
no longer has threading enabled by default. Include additional file systems.gh-91821: Fix unstable
test_from_tuple
test intest_decimal.py
.gh-91217: Deprecate the xdrlib module.
gh-91217: Deprecate the uu module.
gh-91760: More strict rules will be applied for numerical group references and group names in regular expressions. For now, a deprecation warning is emitted for group references and group names which will be errors in future Python versions.
gh-84461: Add provisional
sys._emscripten_info
named tuple with build-time and run-time information about Emscripten platform.gh-90623:
signal.raise_signal()
andos.kill()
now check immediately for pending signals. Patch by Victor Stinner.gh-91734: Fix OSS audio support on Solaris.
gh-90633: Include the passed value in the exception thrown by
typing.assert_never()
. Patch by Jelle Zijlstra.gh-91700: Compilation of regular expression containing a conditional expression
(?(group)...)
now raises an appropriatere.error
if the group number refers to not defined group. Previously an internal RuntimeError was raised.gh-91231: Add an optional keyword shutdown_timeout parameter to the
multiprocessing.BaseManager
constructor. Kill the process if terminate() takes longer than the timeout. Patch by Victor Stinner.gh-91621: Fix
typing.get_type_hints()
forcollections.abc.Callable
. Patch by Shantanu Jain.gh-90568: Parsing
\N
escapes of Unicode Named Character Sequences in aregular expression
raises nowre.error
instead ofTypeError
.gh-91670: Remove deprecated
SO
config variable insysconfig
.gh-91217: Deprecate the telnetlib module.
gh-91217: Deprecate the sunau module.
gh-91217: Deprecate the spwd module.
gh-91217: Deprecate the sndhdr module, as well as inline needed functionality for
email.mime.MIMEAudio
.gh-91616:
re
module, fixfullmatch()
mismatch when using Atomic Grouping or Possessive Quantifiers.gh-91217: Deprecate the “pipes” module.
gh-91217: Deprecate the ossaudiodev module.
bpo-47256:
re
module, limit the maximum capturing group to 1,073,741,823 in 64-bit build, this increases the depth of backtracking.gh-91217: Deprecate the nis module.
gh-91595: Fix the comparison of character and integer inside
Tools.gdb.libpython.write_repr()
. Patch by Yu Liu.gh-74166: Add option to raise all errors from
create_connection()
in anExceptionGroup
when it fails to create a connection. The default remains to raise only the last error that had occurred when multiple addresses were tried.gh-91487: Optimize asyncio UDP speed, over 100 times faster when transferring a large file.
gh-91575: Update case-insensitive matching in the
re
module to the latest Unicode version.gh-90622: In
concurrent.futures.process.ProcessPoolExecutor
disallow the «fork» multiprocessing start method when the newmax_tasks_per_child
feature is used as the mix of threads+fork can hang the child processes. Default to using the safe «spawn» start method in that circumstance if nomp_context
was supplied.gh-89022: In
sqlite3
,SQLITE_MISUSE
result codes are now mapped toInterfaceError
instead ofProgrammingError
. Also, more accurate exceptions are raised when binding parameters fail. Patch by Erlend E. Aasland.gh-91526: Stop calling
os.device_encoding(file.fileno())
inTextIOWrapper
. It was complex, never documented, and didn’t work for most cases. (Patch by Inada Naoki.)gh-88116: Change the frame-related functions in the
inspect
module to return a regular object (that is backwards compatible with the old tuple-like interface) that include the extended PEP 657 position information (end line number, column and end column). The affected functions are:inspect.getframeinfo()
,inspect.getouterframes()
,inspect.getinnerframes()
,inspect.stack()
andinspect.trace()
. Patch by Pablo Galindo.gh-69093: Add indexing and slicing support to
sqlite3.Blob
. Patch by Aviv Palivoda and Erlend E. Aasland.gh-69093: Add context manager support to
sqlite3.Blob
. Patch by Aviv Palivoda and Erlend E. Aasland.gh-91217: Deprecate nntplib.
gh-91217: Deprecate msilib.
gh-91404: Improve the performance of
re
matching by using computed gotos (or «threaded code») on supported platforms and removing expensive pointer indirections.gh-91217: Deprecate the imghdr module.
gh-91217: Deprecate the crypt module.
bpo-47000: Make
TextIOWrapper
uses locale encoding whenencoding="locale"
is specified even in UTF-8 mode.gh-91230:
warnings.catch_warnings()
now accepts arguments forwarnings.simplefilter()
, providing a more concise way to locally ignore warnings or convert them to errors.gh-91217: Deprecate the chunk module.
Add the
TCP_CONNECTION_INFO
option (available on macOS) tosocket
.bpo-47260: Fix
os.closerange()
potentially being a no-op in a Linux seccomp sandbox.bpo-47087: Implement
typing.Required
andtyping.NotRequired
(PEP 655). Patch by David Foster and Jelle Zijlstra.bpo-47061: Deprecate cgi and cgitb.
bpo-47061: Deprecate audioop.
bpo-47000: Add
locale.getencoding()
to get the current locale encoding. It is similar tolocale.getpreferredencoding(False)
but ignores the Python UTF-8 Mode.bpo-42012: Add
wsgiref.types
, containing WSGI-specific types for static type checking.bpo-47227: Suppress expression chaining for more
re
parsing errors.bpo-47211: Remove undocumented and never working function
re.template()
and flagre.TEMPLATE
. This was later reverted in 3.11.0b2 and deprecated instead.bpo-47135:
decimal.localcontext()
now accepts context attributes via keyword argumentsbpo-43323: Fix errors in the
email
module if the charset itself contains undecodable/unencodable characters.bpo-46841: Disassembly of quickened code.
bpo-46681: Forward gzip.compress() compresslevel to zlib.
bpo-45100: Add
typing.get_overloads()
andtyping.clear_overloads()
. Patch by Jelle Zijlstra.bpo-44807:
typing.Protocol
no longer silently replaces__init__()
methods defined on subclasses. Patch by Adrian Garcia Badaracco.bpo-46787: Fix
concurrent.futures.ProcessPoolExecutor
exception memory leakbpo-46720: Add support for path-like objects to
multiprocessing.set_executable()
for Windows to be on a par with Unix-like systems. Patch by Géry Ogam.bpo-46053: Fix OSS audio support on NetBSD.
bpo-45639:
image/avif
andimage/webp
were added tomimetypes
.bpo-46285: Add command-line option
-p
/--protocol
to modulehttp.server
which specifies the HTTP version to which the server is conformant (HTTP/1.1 conformant servers can now be run from the command-line interface of modulehttp.server
). Patch by Géry Ogam.bpo-44791: Accept ellipsis as the last argument of
typing.Concatenate
.bpo-46547: Remove variables leaking into
pydoc.Helper
class namespace.bpo-46415: Fix ipaddress.ip_{address,interface,network} raising TypeError instead of ValueError if given invalid tuple as address parameter.
bpo-46075:
CookieJar
withDefaultCookiePolicy
now can process cookies from localhost with domain=localhost explicitly specified in Set-Cookie header.bpo-45995: Add a «z» option to the string formatting specification that coerces negative zero floating-point values to positive zero after rounding to the format precision. Contributed by John Belmonte.
bpo-26175: Fully implement the
io.BufferedIOBase
orio.TextIOBase
interface fortempfile.SpooledTemporaryFile
objects. This lets them work correctly with higher-level layers (like compression modules). Patch by Carey Metcalfe.bpo-45138: Fix a regression in the
sqlite3
trace callback where bound parameters were not expanded in the passed statement string. The regression was introduced in Python 3.10 by bpo-40318. Patch by Erlend E. Aasland.bpo-44863: Allow
TypedDict
subclasses to also includeGeneric
as a base class in class based syntax. Thereby allowing the user to define a genericTypedDict
, just like a user-defined generic but withTypedDict
semantics.bpo-44587: Fix BooleanOptionalAction to not automatically add a default string. If a default string is desired, use a formatter to add it.
bpo-43827: All positional-or-keyword parameters to
ABCMeta.__new__
are now positional-only to avoid conflicts with keyword arguments to be passed to__init_subclass__()
.bpo-43218: Prevent creation of a venv whose path contains the PATH separator. This could affect the usage of the activate script. Patch by Dustin Rodrigues.
bpo-38435: Add a
process_group
parameter tosubprocess.Popen
to help move more things off of the unsafepreexec_fn
parameter.bpo-42066: Fix cookies getting sorted in
CookieJar.__iter__()
which is an extra behavior and not mentioned in RFC 2965 or Netscape cookie protocol. Now the cookies inCookieJar
follows the order of theSet-Cookie
header. Patch by Iman Kermani.bpo-40617: Add
create_window_function()
tosqlite3.Connection
for creating aggregate window functions. Patch by Erlend E. Aasland.bpo-40676: Convert
csv
to use Argument Clinic forcsv.field_size_limit()
,csv.get_dialect()
,csv.unregister_dialect()
andcsv.list_dialects()
.bpo-39716: Raise an ArgumentError when the same subparser name is added twice to an
argparse.ArgumentParser
. This is consistent with the (default) behavior when the same option string is added twice to an ArgumentParser.bpo-36073: Raise
ProgrammingError
instead of segfaulting on recursive usage of cursors insqlite3
converters. Patch by Sergey Fedoseev.bpo-34975: Adds a
start_tls()
method toStreamWriter
, which upgrades the connection with TLS using the givenSSLContext
.bpo-22276:
Path
methodsglob()
andrglob()
return only directories if pattern ends with a pathname components separator (/
orsep
). Patch by Eisuke Kawashima.bpo-24905: Add
blobopen()
tosqlite3.Connection
.sqlite3.Blob
allows incremental I/O operations on blobs. Patch by Aviv Palivoda and Erlend E. Aasland.
Documentation¶
gh-91888: Add a new
gh
role to the documentation to link to GitHub issues.gh-91783: Document security issues concerning the use of the function
shutil.unpack_archive()
gh-91547: Remove «Undocumented modules» page.
gh-91298: In
importlib.resources.abc
, refined the documentation of the Traversable Protocol, applying changes from importlib_resources 5.7.1.bpo-44347: Clarify the meaning of dirs_exist_ok, a kwarg of
shutil.copytree()
.bpo-36329: Remove “make -C Doc serve” in favour of “make -C Doc htmlview”
bpo-47189: Add a What’s New in Python 3.11 entry for the Faster CPython project. Documentation by Ken Jin and Kumar Aditya.
bpo-38668: Update the introduction to documentation for
os.path
to remove warnings that became irrelevant after the implementations of PEP 383 and PEP 529.bpo-47115: The documentation now lists which members of C structs are part of the Limited API/Stable ABI.
bpo-46962: All docstrings in code snippets are now wrapped into
PyDoc_STR()
to follow the guideline of PEP 7’s Documentation Strings paragraph. Patch by Oleg Iarygin.bpo-26792: Improve the docstrings of
runpy.run_module()
andrunpy.run_path()
. Original patch by Andrew Brezovsky.
Tests¶
gh-92169: Use
warnings_helper.import_deprecated()
to import deprecated modules uniformly in tests. Patch by Hugo van Kemenade.gh-84461: When multiprocessing is enabled, libregrtest can now use a Python executable other than
sys.executable
via the--python
flag.gh-91904: Fix initialization of
PYTHONREGRTEST_UNICODE_GUARD
which prevented running regression tests on non-UTF-8 locale.gh-91752: Added @requires_zlib to test.test_tools.test_freeze.TestFreeze.
gh-91607: Fix
test_concurrent_futures
to test the correct multiprocessing start method context in several cases where the test logic mixed this up.bpo-40280: Threading tests are now skipped on WASM targets without pthread support.
bpo-47109: Test for
ctypes.macholib.dyld
,ctypes.macholib.dylib
, andctypes.macholib.framework
are brought from manual pre-unittest
times toctypes.test
location and structure. Patch by Oleg Iarygin.bpo-29890: Add tests for
ipaddress.IPv4Interface
andipaddress.IPv6Interface
construction with tuple arguments. Original patch and tests by louisom.
Build¶
gh-89452: gdbm-compat is now preferred over ndbm if both are available on the system. This allows avoiding the problematic ndbm.h on macOS.
gh-91731: Python is now built with
-std=c11
compiler option, rather than-std=c99
. Patch by Victor Stinner.bpo-47152: Add script and make target for generating
sre_constants.h
.bpo-47103: Windows
PGInstrument
builds now copy a required DLL into the output directory, making it easier to run the profile stage of a PGO build.
Windows¶
bpo-46907: Update Windows installer to use SQLite 3.38.3.
bpo-47239: Fixed –list and –list-paths output for Lanzador de Python para Windows when used in an active virtual environment.
bpo-46907: Update Windows installer to use SQLite 3.38.2.
bpo-46785: Fix race condition between
os.stat()
and unlinking a file on Windows, by using errors codes returned byFindFirstFileW()
when appropriate inwin32_xstat_impl
.bpo-40859: Update Windows build to use xz-5.2.5
macOS¶
bpo-46907: Update macOS installer to SQLite 3.38.4.
Tools/Demos¶
gh-91583: Fix regression in the code generated by Argument Clinic for functions with the
defining_class
parameter.gh-91575: Add script
Tools/scripts/generate_re_casefix.py
and the make targetregen-re
for generating additional data for case-insensitive matching according to the current Unicode version.gh-91551: Remove the ancient Pynche color editor. It has moved to https://gitlab.com/warsaw/pynche
C API¶
gh-88279: Deprecate the C functions:
PySys_SetArgv()
,PySys_SetArgvEx()
,PySys_SetPath()
. Patch by Victor Stinner.gh-92154: Added the
PyCode_GetCode()
function. This function does the equivalent of the Python codegetattr(code_object, 'co_code')
.gh-92173: Fix the
closure
argument toPyEval_EvalCodeEx()
.gh-91320: Fix C++ compiler warnings about «old-style cast» (
g++ -Wold-style-cast
) in the Python C API. Use C++reinterpret_cast<>
andstatic_cast<>
casts when the Python C API is used in C++. Patch by Victor Stinner.gh-80527: Mark functions as deprecated by PEP 623:
PyUnicode_AS_DATA()
,PyUnicode_AS_UNICODE()
,PyUnicode_GET_DATA_SIZE()
,PyUnicode_GET_SIZE()
. Patch by Victor Stinner.gh-91768:
Py_REFCNT()
,Py_TYPE()
,Py_SIZE()
andPy_IS_TYPE()
functions argument type is nowPyObject*
, rather thanconst PyObject*
. Patch by Victor Stinner.gh-91020: Add
PyBytes_Type.tp_alloc
to initializePyBytesObject.ob_shash
for bytes subclasses.bpo-40421: Add
PyFrame_GetLasti
C-API function to access frame object’sf_lasti
attribute safely from C code.bpo-35134: Remove the
Include/code.h
header file. C extensions should only include the main<Python.h>
header file. Patch by Victor Stinner.bpo-47169:
PyOS_CheckStack()
is now exported in the Stable ABI on Windows.bpo-47169:
PyThread_get_thread_native_id()
is excluded from the stable ABI on platforms where it doesn’t exist (like Solaris).bpo-46343: Added
PyErr_GetHandledException()
andPyErr_SetHandledException()
as simpler alternatives toPyErr_GetExcInfo()
andPyErr_SetExcInfo()
.They are included in the stable ABI.
Python 3.11.0 alpha 7¶
Release date: 2022-04-05
Core and Builtins¶
bpo-47212: Raise
IndentationError
instead ofSyntaxError
for a bareexcept
with no following indent. ImproveSyntaxError
locations for an un-parenthesized generator used as arguments. Patch by Matthieu Dartiailh.bpo-47186: Replace
JUMP_IF_NOT_EG_MATCH
byCHECK_EG_MATCH
+ jump.bpo-47176: Emscripten builds cannot handle signals in the usual way due to platform limitations. Python can now handle signals. To use, set Module.Py_EmscriptenSignalBuffer to be a single byte SharedArrayBuffer and set Py_EMSCRIPTEN_SIGNAL_HANDLING to 1. Writing a number into the SharedArrayBuffer will cause the corresponding signal to be raised into the Python thread.
bpo-47186: Replace
JUMP_IF_NOT_EXC_MATCH
byCHECK_EXC_MATCH
+ jump.bpo-47120: Replace the absolute jump opcode
JUMP_NO_INTERRUPT
by the relativeJUMP_BACKWARD_NO_INTERRUPT
.bpo-46841: Avoid unnecessary allocations when comparing code objects.
bpo-47182: Fix a crash when using a named unicode character like
"\N{digit nine}"
after the main interpreter has been initialized a second time.bpo-47162: WebAssembly cannot deal with bad function pointer casts (different count or types of arguments). Python can now use call trampolines to mitigate the problem. Define
PY_CALL_TRAMPOLINE
to enable call trampolines.bpo-46775: Some Windows system error codes(>= 10000) are now mapped into the correct errno and may now raise a subclass of
OSError
. Patch by Dong-hee Na.bpo-47129: Improve error messages in f-string syntax errors concerning empty expressions.
bpo-47117: Fix a crash if we fail to decode characters in interactive mode if the tokenizer buffers are uninitialized. Patch by Pablo Galindo.
bpo-47127: Speed up calls to c functions with keyword arguments by 25% with specialization. Patch by Kumar Aditya.
bpo-47120: Replaced
JUMP_ABSOLUTE
by the relative jumpJUMP_BACKWARD
.bpo-42197:
PyFrame_FastToLocalsWithError()
andPyFrame_LocalsToFast()
are no longer called during profiling nor tracing. C code can access thef_locals
attribute ofPyFrameObject
by callingPyFrame_GetLocals()
.bpo-47070: Improve performance of
array_inplace_repeat
by reducing the number of invocations ofmemcpy
. Refactor therepeat
and inplacerepeat
methods ofarray
,bytes
,bytearray
andunicodeobject
to use the common_PyBytes_Repeat
.bpo-47053: Reduce de-optimization in the specialized
BINARY_OP_INPLACE_ADD_UNICODE
opcode.bpo-47045: Remove the
f_state
field from the _PyInterpreterFrame struct. Add theowner
field to the _PyInterpreterFrame struct to make ownership explicit to simplify clearing and deallocing frames and generators.bpo-46968: Check for the existence of the «sys/auxv.h» header in
faulthandler
to avoid compilation problems in systems where this header doesn’t exist. Patch by Pablo Galindobpo-46329: Use low bit of
LOAD_GLOBAL
to indicate whether to push aNULL
before the global. Helps streamline the call sequence a bit.bpo-46841: Quicken bytecode in-place by storing it as part of the corresponding
PyCodeObject
.bpo-47012: Speed up iteration of
bytes
andbytearray
by 30%. Patch by Kumar Aditya.bpo-47009: Improved the performance of
list.append()
and list comprehensions by optimizing for the common case, where no resize is needed. Patch by Dennis Sweeney.bpo-47005: Improve performance of
bytearray_repeat
andbytearray_irepeat
by reducing the number of invocations ofmemcpy
.bpo-46829: Deprecate passing a message into
asyncio.Future.cancel()
andasyncio.Task.cancel()
bpo-46993: Speed up
bytearray
creation fromlist
andtuple
by 40%. Patch by Kumar Aditya.bpo-39829: Removed the
__len__()
call when initializing a list and moved initializing tolist_extend
. Patch by Jeremiah Pascual.bpo-46944: Speed up throwing exception in generator with
METH_FASTCALL
calling convention. Patch by Kumar Aditya.bpo-46841: Modify
STORE_SUBSCR
to use an inline cache entry (rather than its oparg) as an adaptive counter.bpo-46841: Use inline caching for
PRECALL
andCALL
, and remove the internal machinery for managing the (now unused) non-inline caches.bpo-46881: Statically allocate and initialize the latin1 characters.
bpo-46838: Improve syntax errors for incorrect function definitions. Patch by Pablo Galindo
bpo-43721: Fix docstrings of
getter
,setter
, anddeleter
to clarify that they create a new copy of the property.bpo-43224: Make grammar changes required for PEP 646.
Library¶
bpo-47208: Allow vendors to override
CTYPES_MAX_ARGCOUNT
.bpo-23689:
re
module: fix memory leak when a match is terminated by a signal or memory allocation failure. Patch by Ma Lin.bpo-47167: Allow overriding a future compliance check in
asyncio.Task
.bpo-47151: When subprocess tries to use vfork, it now falls back to fork if vfork returns an error. This allows use in situations where vfork isn’t allowed by the OS kernel.
bpo-47152: Convert the
re
module into a package. Deprecate modulessre_compile
,sre_constants
andsre_parse
.bpo-4833: Add
ZipFile.mkdir()
bpo-27929: Fix
asyncio.loop.sock_connect()
to only resolve names forsocket.AF_INET
orsocket.AF_INET6
families. Resolution may not make sense for other families, likesocket.AF_BLUETOOTH
andsocket.AF_UNIX
.bpo-14265: Adds the fully qualified test name to unittest output
bpo-47061: Deprecate the aifc module.
bpo-39622: Handle Ctrl+C in asyncio programs to interrupt the main task.
bpo-47101:
hashlib.algorithms_available
now lists only algorithms that are provided by activated crypto providers on OpenSSL 3.0. Legacy algorithms are not listed unless the legacy provider has been loaded into the default OSSL context.bpo-47099: All
URLError
exception messages raised inurllib.request.URLopener
now contain a colon betweenftp error
and the rest of the message. Previously,open_ftp()
missed the colon. Patch by Oleg Iarygin.bpo-47099: Exception chaining is changed from
Exception.with_traceback()
/sys.exc_info()
to PEP 3134. Patch by Oleg Iarygin.bpo-47095:
hashlib
’s internal_blake2
module now preferslibb2
from https://www.blake2.net/ over Python’s vendored copy of blake2.bpo-47098: The Keccak Code Package for
hashlib
’s internal_sha3
module has been replaced with tiny_sha3. The module is used as fallback when Python is built without OpenSSL.bpo-47088: Implement
typing.LiteralString
, part of PEP 675. Patch by Jelle Zijlstra.bpo-42885: Optimize
re.search()
,re.split()
,re.findall()
,re.finditer()
andre.sub()
for regular expressions starting with\A
or^
.bpo-23691: Protect the
re.finditer()
iterator from re-entering.bpo-47067: Optimize calling
GenericAlias
objects by using PEP 590vectorcall
and by replacingPyObject_SetAttrString
withPyObject_SetAttr
.bpo-28080: Add the metadata_encoding parameter in the
zipfile.ZipFile
constructor and the--metadata-encoding
option in thezipfile
CLI to allow reading zipfiles using non-standard codecs to encode the filenames within the archive.bpo-47000: Make
io.text_encoding()
returns «utf-8» when UTF-8 mode is enabled.bpo-42369: Fix thread safety of
zipfile._SharedFile.tell()
to avoid a «zipfile.BadZipFile: Bad CRC-32 for file» exception when reading aZipFile
from multiple threads.bpo-38256: Fix
binascii.crc32()
when it is compiled to use zlib’c crc32 to work properly on inputs 4+GiB in length instead of returning the wrong result. The workaround prior to this was to always feed the function data in increments smaller than 4GiB or to just call the zlib module function.We also have
binascii.crc32()
release the GIL when computing on larger inputs aszlib.crc32()
andhashlib
do.This also boosts performance on Windows as it now uses the zlib crc32 implementation for
binascii.crc32()
for a 2-3x speedup.That the stdlib has a crc32 API in two modules is a known historical oddity. This moves us closer to a single implementation behind them.
bpo-47066: Global inline flags (e.g.
(?i)
) can now only be used at the start of the regular expressions. Using them not at the start of expression was deprecated since Python 3.6.bpo-39394: A warning about inline flags not at the start of the regular expression now contains the position of the flag.
bpo-433030: Add support of atomic grouping (
(?>...)
) and possessive quantifiers (*+
,++
,?+
,{m,n}+
) inregular expressions
.bpo-47062: Implement
asyncio.Runner
context manager.bpo-46382:
dataclass()
slots=True
now correctly omits slots already defined in base classes. Patch by Arie Bovenberg.bpo-47057: Use FASTCALL convention for
FutureIter.throw()
bpo-47061: Deprecate the various modules listed by PEP 594:
aifc, asynchat, asyncore, audioop, cgi, cgitb, chunk, crypt, imghdr, msilib, nntplib, nis, ossaudiodev, pipes, smtpd, sndhdr, spwd, sunau, telnetlib, uu, xdrlib
bpo-34790: Remove passing coroutine objects to
asyncio.wait()
.bpo-47039: Normalize
repr()
of asyncio future and task objects.bpo-2604: Fix bug where doctests using globals would fail when run multiple times.
bpo-45150: Add
hashlib.file_digest()
helper for efficient hashing of file object.bpo-34861: Made cumtime the default sorting key for cProfile
bpo-45997: Fix
asyncio.Semaphore
re-aquiring FIFO order.bpo-47022: The
asynchat
,asyncore
andsmtpd
modules have been deprecated since at least Python 3.6. Their documentation and deprecation warnings and have now been updated to note they will removed in Python 3.12 (PEP 594).bpo-43253: Fix a crash when closing transports where the underlying socket handle is already invalid on the Proactor event loop.
bpo-40280:
select.select()
now passesNULL
toselect
for each empty fdset.bpo-47004: Apply bugfixes from importlib_metadata 4.11.3, including bugfix for EntryPoint.extras, which was returning match objects and not the extras strings.
bpo-46998: Allow subclassing of
typing.Any
. Patch by Shantanu Jain.bpo-46995: Deprecate missing
asyncio.Task.set_name()
for third-party task implementations, schedule making it mandatory in Python 3.13.bpo-46994: Accept explicit contextvars.Context in
asyncio.create_task()
andasyncio.loop.create_task()
.bpo-46981:
typing.get_args(typing.Tuple[()])
now returns()
instead of((),)
.bpo-46968: Add
os.sysconf_names['SC_MINSIGSTKSZ']
.bpo-46985: Upgrade pip wheel bundled with ensurepip (pip 22.0.4)
bpo-46968:
faulthandler
: On Linux 5.14 and newer, dynamically determine size of signal handler stack size CPython allocates usinggetauxval(AT_MINSIGSTKSZ)
. This changes allows for Python extension’s request to Linux kernel to use AMX_TILE instruction set on Sapphire Rapids Xeon processor to succeed, unblocking use of the ISA in frameworks.bpo-46917: The
math.nan
value is now always available. Patch by Victor Stinner.bpo-46955: Expose
asyncio.base_events.Server
asasyncio.Server
. Patch by Stefan Zabka.bpo-23325: The
signal
module no longer assumes thatSIG_IGN
andSIG_DFL
are small int singletons.bpo-46932: Update bundled libexpat to 2.4.7
bpo-46933: The
pwd
module is now optional.os.path.expanduser()
returns the path when thepwd
module is not available.bpo-40059: PEP 680, the
tomllib
module. Adds support for parsing TOML.bpo-464471:
asyncio.timeout()
andasyncio.timeout_at()
context managers added. Patch by Tin Tvrtković and Andrew Svetlov.bpo-46805: Added raw datagram socket functions for asyncio:
sock_sendto()
,sock_recvfrom()
andsock_recvfrom_into()
.bpo-46644: No longer require valid typeforms to be callable. This allows
typing.Annotated
to wraptyping.ParamSpecArgs
anddataclasses.InitVar
. Patch by Gregory Beauregard.bpo-46581: Brings
ParamSpec
propagation forGenericAlias
in line withConcatenate
(and others).bpo-45413: Define posix_venv and nt_venv sysconfig installation schemes to be used for bootstrapping new virtual environments. Add venv sysconfig installation scheme to get the appropriate one of the above. The schemes are identical to the pre-existing posix_prefix and nt install schemes. The
venv
module now uses the venv scheme to create new virtual environments instead of hardcoding the paths depending only on the platform. Downstream Python distributors customizing the posix_prefix or nt install scheme in a way that is not compatible with the install scheme used in virtual environments are encouraged not to customize the venv schemes. When Python itself runs in a virtual environment,sysconfig.get_default_scheme()
andsysconfig.get_preferred_scheme()
withkey="prefix"
returns venv.bpo-43224: Implement support for PEP 646 in typing.py.
bpo-43224: Allow unpacking types.GenericAlias objects, e.g.
*tuple[int, str]
.bpo-46557: Warnings captured by the logging module are now logged without a format string to prevent systems that group logs by the msg argument from grouping captured warnings together.
bpo-41370:
typing.get_type_hints()
now supports evaluating strings as forward references in PEP 585 generic aliases.bpo-46607: Add
DeprecationWarning
toLegacyInterpolation
, deprecated in the docstring since Python 3.2. Will be removed in Python 3.13. UseBasicInterpolation
orExtendedInterpolation
instead.bpo-26120:
pydoc
now excludes __future__ imports from the module’s data items.bpo-46480: Add
typing.assert_type()
. Patch by Jelle Zijlstra.bpo-46421: Fix a unittest issue where if the command was invoked as
python -m unittest
and the filename(s) began with a dot (.), aValueError
is returned.bpo-46245: Add optional parameter dir_fd in
shutil.rmtree()
.bpo-22859:
usageExit()
is marked deprecated, to be removed in 3.13.bpo-46170: Improve the error message when you try to subclass an instance of
typing.NewType
.bpo-20392: Fix inconsistency with uppercase file extensions in
MimeTypes.guess_type()
. Patch by Kumar Aditya.bpo-46030: Add
LOCAL_CREDS
,LOCAL_CREDS_PERSISTENT
andSCM_CREDS2
FreeBSD constants to the socket module.bpo-44439: Fix
.write()
method of a member file inZipFile
, when the input data is an object that supports the buffer protocol, the file length may be wrong.bpo-45171: Fix handling of the
stacklevel
argument to logging functions in thelogging
module so that it is consistent across all logging functions and, as advertised, similar to thestacklevel
argument used inwarn()
.bpo-24959: Fix bug where
unittest
sometimes drops frames from tracebacks of exceptions raised in tests.bpo-44859: Raise more accurate and PEP 249 compatible exceptions in
sqlite3
.Raise
InterfaceError
instead ofProgrammingError
forSQLITE_MISUSE
errors.Don’t overwrite
BufferError
withValueError
when conversion to BLOB fails.Raise
ProgrammingError
instead ofWarning
if user tries toexecute()
more than one SQL statement.Raise
ProgrammingError
instead ofValueError
if an SQL query contains null characters.
bpo-44493: Add missing terminated NUL in sockaddr_un’s length
This was potentially observable when using non-abstract AF_UNIX datagram sockets to processes written in another programming language.
bpo-41930: Add
serialize()
anddeserialize()
support tosqlite3
. Patch by Erlend E. Aasland.bpo-33178: Added
ctypes.BigEndianUnion
andctypes.LittleEndianUnion
classes, as originally documented in the library docs but not yet implemented.bpo-43352: Add an Barrier object in synchronization primitives of asyncio Lib in order to be consistant with Barrier from threading and multiprocessing libs*
bpo-35859:
re
module, fix a few bugs about capturing group. In rare cases, capturing group gets an incorrect string. Patch by Ma Lin.
Documentation¶
bpo-47040: Clarified the old Python versions compatiblity note of
binascii.crc32()
/zlib.adler32()
/zlib.crc32()
functions.bpo-46033: Clarify
for
statement execution in its doc.bpo-45790: Adjust inaccurate phrasing in Definición de tipos de extensión: Tutorial about the
ob_base
field and the macros used to access its contents.bpo-42340: Document that in some circumstances
KeyboardInterrupt
may cause the code to enter an inconsistent state. Provided a sample workaround to avoid it if needed.bpo-41233: Link the errnos referenced in
Doc/library/exceptions.rst
to their respective section inDoc/library/errno.rst
, and vice versa. Previously this was only done for EINTR and InterruptedError. Patch by Yan «yyyyyyyan» Orestes.
Tests¶
bpo-47205: Skip test for
sched_getaffinity()
andsched_setaffinity()
error case on FreeBSD.bpo-46126: Restore “descriptions” when running tests internally.
bpo-47104: Rewrite
asyncio.to_thread()
tests to useunittest.IsolatedAsyncioTestCase
.bpo-40280: The test suite is now passing on the Emscripten platform. All fork, socket, and subprocess-based tests are skipped.
bpo-47037: Skip
strftime("%4Y")
feature test on Windows. It can cause an assertion error in debug builds.bpo-46587: Skip tests if platform’s
strftime
does not support non-portable glibc extensions.bpo-47015: A test case for
os.sendfile()
is converted from deprecatedasyncore
(see PEP 594) toasyncio
. Patch by Oleg Iarygin.
Build¶
bpo-40280: Add configure option
--enable-wasm-dynamic-linking
to enabledlopen
and MAIN_MODULE / SIDE_MODULE onwasm32-emscripten
.bpo-46023:
makesetup
now detects and skips all duplicated module definitions. The first entry wins.bpo-40280: Add SOABI
wasm32-emscripten
for Emscripten andwasm32-wasi
for WASI on 32bit WASM as well aswasm64
counter parts.bpo-47032: Ensure Windows install builds fail correctly with a non-zero exit code when part of the build fails.
bpo-47024: Update OpenSSL to 1.1.1n for macOS installers and all Windows builds.
bpo-46996: The
tkinter
package now requires Tcl/Tk version 8.5.12 or newer.bpo-46973: Add
regen-configure
make target to regenerate configure script with Christian’s container imagequay.io/tiran/cpython_autoconf:269
.bpo-46917: Building Python now requires support of IEEE 754 floating point numbers. Patch by Victor Stinner.
bpo-45774:
configure
now verifies that all SQLite C APIs needed for thesqlite3
extension module are found.
Windows¶
bpo-47194: Update
zlib
to v1.2.12 to resolve CVE-2018-25032.bpo-47171: Enables installing the
py.exe
launcher on Windows ARM64.bpo-46566: Upgraded Lanzador de Python para Windows to support a new
-V:company/tag
argument for full PEP 514 support and to detect ARM64 installs. The-64
suffix on arguments is deprecated, but still selects any non-32-bit install. SettingPYLAUNCHER_ALLOW_INSTALL
and specifying a version that is not installed will attempt to install the requested version from the Microsoft Store.bpo-47086: The installer for Windows now includes documentation as loose HTML files rather than a single compiled
.chm
file.bpo-46907: Update Windows installer to use SQLite 3.38.1.
bpo-44549: Update bzip2 to 1.0.8 in Windows builds to mitigate CVE-2016-3189 and CVE-2019-12900
bpo-46948: Prevent CVE-2022-26488 by ensuring the Add to PATH option in the Windows installer uses the correct path when being repaired.
macOS¶
Tools/Demos¶
bpo-40280: Replace Emscripten’s limited shell with Katie Bell’s browser-ui REPL from python-wasm project.
C API¶
bpo-40421: Add
PyFrame_GetBuiltins
,PyFrame_GetGenerator
andPyFrame_GetGlobals
C-API functions to access frame object attributes safely from C code.bpo-46850: Move the private
_PyFrameEvalFunction
type, and private_PyInterpreterState_GetEvalFrameFunc()
and_PyInterpreterState_SetEvalFrameFunc()
functions to the internal C API. The_PyFrameEvalFunction
callback function type now uses the_PyInterpreterFrame
type which is part of the internal C API. Patch by Victor Stinner.bpo-46850: Move the private undocumented
_PyEval_EvalFrameDefault()
function to the internal C API. The function now uses the_PyInterpreterFrame
type which is part of the internal C API. Patch by Victor Stinner.bpo-46850: Remove the private undocumented function
_PyEval_CallTracing()
from the C API. Call the publicsys.call_tracing()
function instead. Patch by Victor Stinner.bpo-46850: Remove the private undocumented function
_PyEval_GetCoroutineOriginTrackingDepth()
from the C API. Call the publicsys.get_coroutine_origin_tracking_depth()
function instead. Patch by Victor Stinner.bpo-46850: Remove the following private undocumented functions from the C API:
_PyEval_GetAsyncGenFirstiter()
_PyEval_GetAsyncGenFinalizer()
_PyEval_SetAsyncGenFirstiter()
_PyEval_SetAsyncGenFinalizer()
Call the public
sys.get_asyncgen_hooks()
andsys.set_asyncgen_hooks()
functions instead. Patch by Victor Stinner.bpo-46987: Remove private functions
_PySys_GetObjectId()
and_PySys_SetObjectId()
. Patch by Dong-hee Na.bpo-46906: Add new functions to pack and unpack C double (serialize and deserialize):
PyFloat_Pack2()
,PyFloat_Pack4()
,PyFloat_Pack8()
,PyFloat_Unpack2()
,PyFloat_Unpack4()
andPyFloat_Unpack8()
. Patch by Victor Stinner.
Python 3.11.0 alpha 6¶
Release date: 2022-03-07
Core and Builtins¶
bpo-46940: Avoid overriding
AttributeError
metadata information for nested attribute access calls. Patch by Pablo Galindo.bpo-46927: Include the type’s name in the error message for subscripting non-generic types.
bpo-46921: Support vectorcall for
super()
. Patch by Ken Jin.bpo-46841: Fix incorrect handling of inline cache entries when specializing
BINARY_OP
.bpo-46841: Use an oparg to simplify the construction of helpful error messages in
GET_AWAITABLE
.bpo-46903: Make sure that str subclasses can be used as attribute names for instances with virtual dictionaries. Fixes regression in 3.11alpha
bpo-46841: Add more detailed specialization failure stats for
COMPARE_OP
followed byEXTENDED_ARG
.bpo-46891: Fix bug introduced during 3.11alpha where subclasses of
types.ModuleType
with__slots__
were not initialized correctly, resulting in an interpreter crash.bpo-46841: Use inline caching for
LOAD_ATTR
,LOAD_METHOD
, andSTORE_ATTR
.bpo-46841: Use inline cache for
BINARY_SUBSCR
.bpo-46841: Use inline caching for
COMPARE_OP
.bpo-46864: Deprecate
PyBytesObject.ob_shash
. It will be removed in Python 3.13.bpo-46841: Use inline caching for
UNPACK_SEQUENCE
.bpo-46845: Reduces dict size by removing hash value from hash table when all inserted keys are Unicode. For example,
sys.getsizeof(dict.fromkeys("abcdefg"))
becomes 272 bytes from 352 bytes on 64bit platform.bpo-46841: Use inline cache for
LOAD_GLOBAL
.bpo-46852: Rename the private undocumented
float.__set_format__()
method tofloat.__setformat__()
to fix a typo introduced in Python 3.7. The method is only used by test_float. Patch by Victor Stinner.bpo-46852: Remove the undocumented private
float.__set_format__()
method, previously known asfloat.__setformat__()
in Python 3.7. Its docstring said: «You probably don’t want to use this function. It exists mainly to be used in Python’s test suite.» Patch by Victor Stinner.bpo-40116: Fix regression that dict.update(other) may don’t respect iterate order of other when other is key sharing dict.
bpo-46712: Share global string identifiers in deep-frozen modules.
bpo-46430: Fix memory leak in interned strings of deep-frozen modules.
bpo-46841: Store
BINARY_OP
caches inline using a newCACHE
instruction.bpo-45107: Specialize
LOAD_METHOD
for instances with a dict.bpo-44337: Reduce the memory usage of specialized
LOAD_ATTR
andSTORE_ATTR
instructions.bpo-46729: Add number of sub-exceptions to
BaseException.__str__()
.bpo-45885: Don’t un-adapt
COMPARE_OP
when collecting specialization stats.bpo-46329: Fix specialization stats gathering for
PRECALL
instructions.bpo-46794: Bump up the libexpat version into 2.4.6
bpo-46823: Implement a specialized combined opcode
LOAD_FAST__LOAD_ATTR_INSTANCE_VALUE
. Patch by Dennis Sweeney.bpo-46820: Fix parsing a numeric literal immediately (without spaces) followed by «not in» keywords, like in
1not in x
. Now the parser only emits a warning, not a syntax error.bpo-46329: Move
KW_NAMES
beforePRECALL
instruction in call sequence. Changeoperand
ofCALL
to matchPRECALL
for easier specialization.bpo-46808: Remove the
NEXT_BLOCK
macro from compile.c, and make the compiler automatically generate implicit blocks when they are needed.bpo-46329: Add
PUSH_NULL
instruction. This is used as a prefix when evaluating a callable, so that the stack has the same shape for methods and other calls.PRECALL_FUNCTION
andPRECALL_METHOD
are merged into a singlePRECALL
instruction.There is no change in semantics.
bpo-46762: Fix an assert failure in debug builds when a “<”, “>”, or “=” is the last character in an f-string that’s missing a closing right brace.
bpo-46730: Message of AttributeError caused by getting, setting or deleting a property without the corresponding function now mentions that the attribute is in fact a property and also specifies type of the class that it belongs to.
bpo-46724: Make sure that all backwards jumps use the
JUMP_ABSOLUTE
instruction, rather thanJUMP_FORWARD
with an argument of(2**32)+offset
.bpo-46732: Correct the docstring for the
__bool__()
method. Patch by Jelle Zijlstra.bpo-46072: Add more detailed specialization failure statistics for
BINARY_OP
.bpo-46707: Avoid potential exponential backtracking when producing some syntax errors involving lots of brackets. Patch by Pablo Galindo.
bpo-46323:
ctypes
now allocates memory on the stack instead of on the heap to pass arguments while calling a Python callback function. Patch by Dong-hee Na.bpo-45923: Add a quickened form of
RESUME
that skips quickening checks.bpo-46702: Specialize
UNPACK_SEQUENCE
fortuple
andlist
unpackings.bpo-46072: Opcode pair stats are now gathered with
--enable-pystats
. DefiningDYNAMIC_EXECUTION_PROFILE
orDXPAIRS
no longer has any effect.bpo-46675: Allow more than 16 items in a split dict before it is combined. The limit is now 254.
bpo-40479: Add a missing call to
va_end()
inModules/_hashopenssl.c
.bpo-46323: Use
PyObject_Vectorcall()
while calling ctypes callback function. Patch by Dong-hee Na.bpo-46615: When iterating over sets internally in
setobject.c
, acquire strong references to the resulting items from the set. This prevents crashes in corner-cases of various set operations where the set gets mutated.bpo-45828: The bytecode compiler now attempts to apply runtime stack manipulations at compile-time (whenever it is feasible to do so).
bpo-30496: Fixed a minor portability issue in the implementation of
PyLong_FromLong()
, and added a fast path for single-digit integers toPyLong_FromLongLong()
.
Library¶
bpo-25707: Fixed a file leak in
xml.etree.ElementTree.iterparse()
when the iterator is not exhausted. Patch by Jacob Walls.bpo-46877: Export
unittest.doModuleCleanups()
inunittest
. Patch by Kumar Aditya.bpo-46848: For performance, use the optimized string-searching implementations from
find()
andrfind()
forfind()
andrfind()
.bpo-46736:
SimpleHTTPRequestHandler
now uses HTML5 grammar. Patch by Dong-hee Na.bpo-44886: Inherit asyncio proactor datagram transport from
asyncio.DatagramTransport
.bpo-46827: Support UDP sockets in
asyncio.loop.sock_connect()
for selector-based event loops. Patch by Thomas Grainger.bpo-46811: Make test suite support Expat >=2.4.5
bpo-46252: Raise
TypeError
ifssl.SSLSocket
is passed to transport-based APIs.bpo-46784: Fix libexpat symbols collisions with user dynamically loaded or statically linked libexpat in embedded Python.
bpo-46786: The HTML serialisation in xml.etree.ElementTree now writes
embed
,source
,track
andwbr
as empty tags, as defined in HTML 5.bpo-39327:
shutil.rmtree()
can now work with VirtualBox shared folders when running from the guest operating-system.bpo-45390: Propagate
asyncio.CancelledError
message from inner task to outer awaiter.bpo-46756: Fix a bug in
urllib.request.HTTPPasswordMgr.find_user_password()
andurllib.request.HTTPPasswordMgrWithPriorAuth.is_authenticated()
which allowed to bypass authorization. For example, access to URIexample.org/foobar
was allowed if the user was authorized for URIexample.org/foo
.bpo-46737:
random.gauss()
andrandom.normalvariate()
now have default arguments.bpo-46752: Add task groups to asyncio (structured concurrency, inspired by Trio’s nurseries). This also introduces a change to task cancellation, where a cancelled task can’t be cancelled again until it calls .uncancel().
bpo-46333: The
__repr__()
method oftyping.ForwardRef
now includes themodule
parameter oftyping.ForwardRef
when it is set.bpo-46643: In
typing.get_type_hints()
, support evaluating stringifiedParamSpecArgs
andParamSpecKwargs
annotations. Patch by Gregory Beauregard.bpo-45863: When the
tarfile
module creates a pax format archive, it will put an integer representation of timestamps in the ustar header (if possible) for the benefit of older unarchivers, in addition to the existing full-precision timestamps in the pax extended header.bpo-46066: Deprecate kwargs-based syntax for
typing.TypedDict
definitions. It had confusing semantics when specifying totality, and was largely unused. Patch by Jingchen Ye.bpo-46676: Make
typing.ParamSpec
args and kwargs equal to themselves. Patch by Gregory Beauregard.bpo-46323:
ctypes.CFUNCTYPE()
andctypes.WINFUNCTYPE()
now fail to create the type if its_argtypes_
member contains too many arguments. Previously, the error was only raised when calling a function. Patch by Victor Stinner.bpo-46672: Fix
NameError
inasyncio.gather()
when initial type check fails.bpo-46659: The
calendar.LocaleTextCalendar
andcalendar.LocaleHTMLCalendar
classes now uselocale.getlocale()
, instead of usinglocale.getdefaultlocale()
, if no locale is specified. Patch by Victor Stinner.bpo-46659: The
locale.getdefaultlocale()
function is deprecated and will be removed in Python 3.13. Uselocale.setlocale()
,locale.getpreferredencoding(False)
andlocale.getlocale()
functions instead. Patch by Victor Stinner.bpo-46655: In
typing.get_type_hints()
, support evaluating bare stringifiedTypeAlias
annotations. Patch by Gregory Beauregard.bpo-45948: Fixed a discrepancy in the C implementation of the
xml.etree.ElementTree
module. Now, instantiating anxml.etree.ElementTree.XMLParser
with atarget=None
keyword provides a defaultxml.etree.ElementTree.TreeBuilder
target as the Python implementation does.bpo-46626: Expose Linux’s
IP_BIND_ADDRESS_NO_PORT
option insocket
.bpo-46521: Fix a bug in the
codeop
module that was incorrectly identifying invalid code involving string quotes as valid code.bpo-46571: Improve
typing.no_type_check()
.Now it does not modify external classes and functions. We also now correctly mark classmethods as not to be type checked.
bpo-46400: expat: Update libexpat from 2.4.1 to 2.4.4
bpo-46556: Deprecate undocumented support for using a
pathlib.Path
object as a context manager.bpo-46534: Implement PEP 673
typing.Self
. Patch by James Hilton-Balfe.bpo-46522: Make various module
__getattr__
AttributeErrors more closely match a typical AttributeErrorbpo-46475: Add
typing.Never
andtyping.assert_never()
. Patch by Jelle Zijlstra.bpo-46333: The
__eq__()
and__hash__()
methods oftyping.ForwardRef
now honor themodule
parameter oftyping.ForwardRef
. Forward references from different modules are now differentiated.bpo-46246: Add missing
__slots__
toimportlib.metadata.DeprecatedList
. Patch by Arie Bovenberg.bpo-46232: The
ssl
module now handles certificates with bit strings in DN correctly.bpo-46195:
typing.get_type_hints()
no longer addsOptional
to parameters withNone
as a default. This aligns to changes to PEP 484 in https://github.com/python/peps/pull/689bpo-31369: Add
RegexFlag
tore.__all__
and documented it. AddNOFLAG
to indicate no flags being set.bpo-45898:
ctypes
no longer definesffi_type_*
symbols incfield.c
. The symbols have been provided by libffi for over a decade.bpo-44953: Calling
operator.itemgetter
objects andoperator.attrgetter
objects is now faster due to use of the vectorcall calling convention.bpo-44289: Fix an issue with
is_tarfile()
method when using fileobj argument: position in the fileobj was advanced forward which made it unreadable withtarfile.TarFile.open()
.bpo-44011: Reimplement SSL/TLS support in asyncio, borrow the implementation from uvloop library.
bpo-41086: Make the
configparser.ConfigParser
constructor raiseTypeError
if theinterpolation
parameter is not of typeconfigparser.Interpolation
bpo-29418: Implement
inspect.ismethodwrapper()
and fixinspect.isroutine()
for cases where methodwrapper is given. Patch by Hakan Çelik.bpo-14156: argparse.FileType now supports an argument of “-” in binary mode, returning the .buffer attribute of sys.stdin/sys.stdout as appropriate. Modes including “x” and “a” are treated equivalently to “w” when argument is “-”. Patch contributed by Josh Rosenberg
Documentation¶
bpo-42238:
Doc/tools/rstlint.py
has moved to its own repository and is now packaged on PyPI assphinx-lint
.
Tests¶
bpo-46913: Fix test_faulthandler.test_sigfpe() if Python is built with undefined behavior sanitizer (UBSAN): disable UBSAN on the faulthandler_sigfpe() function. Patch by Victor Stinner.
bpo-46760: Remove bytecode offsets from expected values in test.test_dis module. Reduces the obstacles to modifying the VM or compiler.
bpo-46708: Prevent default asyncio event loop policy modification warning after
test_asyncio
execution.bpo-46678: The function
make_legacy_pyc
inLib/test/support/import_helper.py
no longer fails whenPYTHONPYCACHEPREFIX
is set to a directory on a different device from where tempfiles are stored.bpo-46623: Skip test_pair() and test_speech128() of test_zlib on s390x since they fail if zlib uses the s390x hardware accelerator. Patch by Victor Stinner.
Build¶
bpo-46860: Respect
--with-suffix
when building on case-insensitive file systems.bpo-46656: Building Python now requires a C11 compiler. Optional C11 features are not required. Patch by Victor Stinner.
bpo-46656: Building Python now requires support for floating point Not-a-Number (NaN): remove the
Py_NO_NAN
macro. Patch by Victor Stinner.bpo-46640: Building Python now requires a C99
<math.h>
header file providing aNAN
constant, or the__builtin_nan()
built-in function. Patch by Victor Stinner.bpo-46608: Exclude marshalled-frozen data if deep-freezing to save 300 KB disk space. This includes adding a new
is_package
field to_frozen
. Patch by Kumar Aditya.bpo-40280: Fix wasm32-emscripten test failures and platform issues. - Disable syscalls that are not supported or don’t work, e.g. wait, getrusage, prlimit, mkfifo, mknod, setres[gu]id, setgroups. - Use fd_count to cound open fds. - Add more checks for subprocess and fork. - Add workarounds for missing _multiprocessing and failing socket.accept(). - Enable bzip2. - Disable large file support. - Disable signal.alarm.
bpo-46430: Intern strings in deep-frozen modules. Patch by Kumar Aditya.
Windows¶
bpo-46744: The default all users install directory for ARM64 is now under the native
Program Files
folder, rather thanProgram Files (Arm)
which is intended for ARM (32-bit) files.bpo-46567: Adds Tcl and Tk support for Windows ARM64. This also adds IDLE to the installation.
bpo-46638: Ensures registry virtualization is consistently disabled. For 3.10 and earlier, it remains enabled (some registry writes are protected), while for 3.11 and later it is disabled (registry modifications affect all applications).
IDLE¶
C API¶
bpo-46748: Python’s public headers no longer import
<stdbool.h>
, leaving code that embedd/extends Python free to definebool
,true
andfalse
.bpo-46836: Move the
PyFrameObject
type definition (struct _frame
) to the internal C APIpycore_frame.h
header file. Patch by Victor Stinner.bpo-45459: Rename
Include/buffer.h
header file toInclude/pybuffer.h
to avoid conflits with projects having an existingbuffer.h
header file. Patch by Victor Stinner.bpo-45412: Remove the
HAVE_PY_SET_53BIT_PRECISION
macro (moved to the internal C API). Patch by Victor Stinner.bpo-46613: Added function
PyType_GetModuleByDef()
, which allows accesss to module state when a method’s defining class is not available.
Python 3.11.0 alpha 5¶
Release date: 2022-02-03
Core and Builtins¶
bpo-45773: Remove two invalid «peephole» optimizations from the bytecode compiler.
bpo-46564: Do not create frame objects when creating
super
object. Patch by Kumar Aditya.bpo-45885: Added more fined-grained specialization failure stats regarding the
COMPARE_OP
bytecode.bpo-44977: The delegation of
int()
to__trunc__()
is now deprecated. Callingint(a)
whentype(a)
implements__trunc__()
but not__int__()
or__index__()
now raises aDeprecationWarning
.bpo-46458: Reorder code emitted by the compiler for a
try
-except
block so that theelse
block’s code immediately follows thetry
body (without a jump). This is more optimal for the happy path.bpo-46527: Allow passing
iterable
as a keyword argument toenumerate()
again. Patch by Jelle Zijlstra.bpo-46528: Replace several stack manipulation instructions (
DUP_TOP
,DUP_TOP_TWO
,ROT_TWO
,ROT_THREE
,ROT_FOUR
, andROT_N
) with newCOPY
andSWAP
instructions.bpo-46329: Use two or three bytecodes to implement most calls.
Calls without named arguments are implemented as a sequence of two instructions:
PRECALL; CALL
. Calls with named arguments are implemented as a sequence of three instructions:PRECALL; KW_NAMES; CALL
. There are two differentPRECALL
instructions:PRECALL_FUNTION
andPRECALL_METHOD
. The latter pairs withLOAD_METHOD
.This partition into pre-call and call allows better specialization, and thus better performance ultimately.
There is no change in semantics.
bpo-46503: Fix an assert when parsing some invalid N escape sequences in f-strings.
bpo-46431: Improve error message on invalid calls to
BaseExceptionGroup.__new__()
.bpo-46476: Fix memory leak in code objects generated by deepfreeze. Patch by Kumar Aditya.
bpo-46481: Speed up calls to
weakref.ref.__call__()
by using the PEP 590vectorcall
calling convention. Patch by Dong-hee Na.bpo-46417: Fix a race condition on setting a type
__bases__
attribute: the internal functionadd_subclass()
now gets thePyTypeObject.tp_subclasses
member after callingPyWeakref_NewRef()
which can trigger a garbage collection which can indirectly modifyPyTypeObject.tp_subclasses
. Patch by Victor Stinner.bpo-46417:
python -X showrefcount
now shows the total reference count after clearing and destroyed the main Python interpreter. Previously, it was shown before. Patch by Victor Stinner.bpo-43683: Add ASYNC_GEN_WRAP opcode to wrap the value to be yielded in async generators. Removes the need to special case async generators in the
YIELD_VALUE
instruction.bpo-46407: Optimize some modulo operations in
Objects/longobject.c
. Patch by Jeremiah Vivian.bpo-46409: Add new
RETURN_GENERATOR
bytecode to make generators. Simplifies calling Python functions in the VM, as they no longer any need to special case generator functions.Also add
JUMP_NO_INTERRUPT
bytecode that acts likeJUMP_ABSOLUTE
, but does not check for interrupts.bpo-46406: The integer division
//
implementation has been optimized to better let the compiler understand its constraints. It can be 20% faster on the amd64 platform when dividing an int by a value smaller than2**30
.bpo-46383: Fix invalid signature of
_zoneinfo
’smodule_free
function to resolve a crash on wasm32-emscripten platform.bpo-46361: Ensure that «small» integers created by
int.from_bytes()
anddecimal.Decimal
are properly cached.bpo-46161: Fix the class building error when the arguments are constants and CALL_FUNCTION_EX is used.
bpo-46028: Fixes calculation of
sys._base_executable
when inside a virtual environment that uses symlinks with different binary names than the base environment provides.bpo-46091: Correctly calculate indentation levels for lines with whitespace character that are ended by line continuation characters. Patch by Pablo Galindo
bpo-30512: Add CAN Socket support for NetBSD.
bpo-46045: Do not use POSIX semaphores on NetBSD
bpo-44024: Improve the exc:
TypeError
message for non-string second arguments passed to the built-in functionsgetattr()
andhasattr()
. Patch by Géry Ogam.
Library¶
bpo-46624: Restore support for non-integer arguments of
random.randrange()
andrandom.randint()
.bpo-46591: Make the IDLE doc URL on the About IDLE dialog clickable.
bpo-46565: Remove loop variables that are leaking into modules” namespaces.
bpo-46553: In
typing.get_type_hints()
, support evaluating bare stringifiedClassVar
annotations. Patch by Gregory Beauregard.bpo-46544: Don’t leak
x
&uspace
intermediate vars intextwrap.TextWrapper
.bpo-46487: Add the
get_write_buffer_limits
method toasyncio.transports.WriteTransport
and to the SSL transport.bpo-45173: Note the configparser deprecations will be removed in Python 3.12.
bpo-45162: The deprecated
unittest
APIs removed in 3.11a1 have been temporarily restored to be removed in 3.12 while cleanups in external projects go in.bpo-46539: In
typing.get_type_hints()
, support evaluating stringifiedClassVar
andFinal
annotations insideAnnotated
. Patch by Gregory Beauregard.bpo-46510: Add missing test for
types.TracebackType
andtypes.FrameType
. Calculate them directly from the caught exception without callingsys.exc_info()
.bpo-46491: Allow
typing.Annotated
to wraptyping.Final
andtyping.ClassVar
. Patch by Gregory Beauregard.bpo-46483: Remove
__class_getitem__()
frompathlib.PurePath
as this class was not supposed to be generic.bpo-46436: Fix command-line option
-d
/--directory
in modulehttp.server
which is ignored when combined with command-line option--cgi
. Patch by Géry Ogam.bpo-41403: Make
mock.patch()
raise aTypeError
with a relevant error message on invalid arg. Previously it allowed a crypticAttributeError
to escape.bpo-46474: In
importlib.metadata.EntryPoint.pattern
, avoid potential REDoS by limiting ambiguity in consecutive whitespace.bpo-46474: Removed private method from
importlib.metadata.Path
. Sync with importlib_metadata 4.10.0.bpo-46470: Remove unused branch from
typing._remove_dups_flatten
bpo-46469:
asyncio
generic classes now returntypes.GenericAlias
in__class_getitem__
instead of the same class.bpo-41906: Support passing filter instances in the
filters
values ofhandlers
andloggers
in the dictionary passed tologging.config.dictConfig()
.bpo-46422: Use
dis.Positions
indis.Instruction
instead of a regulartuple
.bpo-46434:
pdb
now gracefully handleshelp
when__doc__
is missing, for example when run with pregenerated optimized.pyc
files.bpo-43869: Python uses the same time Epoch on all platforms. Add an explicit unit test to ensure that it’s the case. Patch by Victor Stinner.
bpo-46414: Add
typing.reveal_type()
. Patch by Jelle Zijlstra.bpo-40280:
subprocess
now imports Windows-specific imports whenmsvcrt
module is available, and POSIX-specific imports on all other platforms. This gives a clean exception when_posixsubprocess
is not available (e.g. Emscripten browser target).bpo-40066:
IntEnum
,IntFlag
, andStrEnum
use the mixed-in type for theirstr()
andformat()
output.bpo-46316: Optimize
pathlib.Path.iterdir()
by removing an unnecessary check for special entries.bpo-29688: Document
pathlib.Path.absolute()
(which has always existed).bpo-43012: The pathlib module’s obsolete and internal
_Accessor
class has been removed to prepare the terrain for upcoming enhancements to the module.bpo-46258: Speed up
math.isqrt()
for small positive integers by replacing two division steps with a lookup table.bpo-46242: Improve error message when creating a new
enum.Enum
type subclassing an existingEnum
with_member_names_
usingenum.Enum.__call__()
.bpo-43118: Fix a bug in
inspect.signature()
that was causing it to fail on some subclasses of classes with a__text_signature__
referencing module globals. Patch by Weipeng Hong.bpo-26552: Fixed case where failing
asyncio.ensure_future()
did not close the coroutine. Patch by Kumar Aditya.bpo-21987: Fix an issue with
tarfile.TarFile.getmember()
getting a directory name with a trailing slash.bpo-46124: Update
zoneinfo
to rely on importlib.resources traversable API.bpo-46103: Now
inspect.getmembers()
only gets__bases__
attribute from class type. Patch by Weipeng Hong.bpo-46080: Fix exception in argparse help text generation if a
argparse.BooleanOptionalAction
argument’s default isargparse.SUPPRESS
and it hashelp
specified. Patch by Felix Fontein.bpo-44791: Fix substitution of
ParamSpec
inConcatenate
with different parameter expressions. Substitution with a list of types returns now a tuple of types. Substitution withConcatenate
returns now aConcatenate
with concatenated lists of arguments.
Documentation¶
bpo-46463: Fixes
escape4chm.py
script used when building the CHM documentation file
Tests¶
bpo-43478: Mocks can no longer be provided as the specs for other Mocks. As a result, an already-mocked object cannot be passed to
mock.Mock()
. This can uncover bugs in tests since these Mock-derived Mocks will always pass certain tests (e.g. isinstance) and builtin assert functions (e.g. assert_called_once_with) will unconditionally pass.bpo-46616: Ensures
test_importlib.test_windows
cleans up registry keys after completion.bpo-44359: test_ftplib now silently ignores socket errors to prevent logging unhandled threading exceptions. Patch by Victor Stinner.
bpo-46600: Fix test_gdb.test_pycfunction() for Python built with
clang -Og
. Tolerate inlined functions in the gdb traceback. Patch by Victor Stinner.bpo-46542: Fix a Python crash in test_lib2to3 when using Python built in debug mode: limit the recursion limit. Patch by Victor Stinner.
bpo-46576: test_peg_generator now disables compiler optimization when testing compilation of its own C extensions to significantly speed up the testing on non-debug builds of CPython.
bpo-46542: Fix
test_json
tests checking forRecursionError
: modify these tests to usesupport.infinite_recursion()
. Patch by Victor Stinner.bpo-13886: Skip test_builtin PTY tests on non-ASCII characters if the readline module is loaded. The readline module changes input() behavior, but test_builtin is not intented to test the readline module. Patch by Victor Stinner.
bpo-40280: Add
test.support.requires_fork()
decorators to mark tests that require a workingos.fork()
.bpo-40280: Add
test.support.requires_subprocess()
decorator to mark tests which require workingsubprocess
module oros.spawn*
. The wasm32-emscripten platform has no support for processes.bpo-46126: Disable “descriptions” when running tests internally.
Build¶
bpo-46602: Tidied up configure.ac so that conftest.c is truncated rather than appended. This assists in the case where the “rm” of conftest.c fails to happen between tests. Downstream issues such as a clobbered SOABI can result.
bpo-46600: Fix the test checking if the C compiler supports
-Og
option in the./configure
script to also use-Og
on clang which supports it. Patch by Victor Stinner.bpo-38472: Fix GCC detection in setup.py when cross-compiling. The C compiler is now run with LC_ALL=C. Previously, the detection failed with a German locale.
bpo-46513: configure no longer uses
AC_C_CHAR_UNSIGNED
macro andpyconfig.h
no longer defines reserved symbol__CHAR_UNSIGNED__
.bpo-46471: Use global singletons for single byte bytes objects in deepfreeze.
bpo-46443: Deepfreeze now uses cached small integers as it saves some space for common small integers.
bpo-46429: Merge all deep-frozen files into one for space savings. Patch by Kumar Aditya.
bpo-45569: The build now defaults to using 30-bit digits for Python integers. Previously either 15-bit or 30-bit digits would be selected, depending on the platform. 15-bit digits may still be selected using the
--enable-big-digits=15
option to theconfigure
script, or by definingPYLONG_BITS_IN_DIGIT
inpyconfig.h
.bpo-45925: Update Windows installer to use SQLite 3.37.2.
bpo-43112: Detect musl libc as a separate SOABI (tagged as
linux-musl
).
Windows¶
bpo-33125: The traditional EXE/MSI based installer for Windows is now available for ARM64
bpo-46362: os.path.abspath(«C:CON») is now fixed to return «\.CON», not the same path. The regression was true of all legacy DOS devices such as COM1, LPT1, or NUL.
bpo-44934: The installer now offers a command-line only option to add the installation directory to the end of
PATH
instead of at the start.
macOS¶
bpo-45925: Update macOS installer to SQLite 3.37.2.
IDLE¶
bpo-45296: Clarify close, quit, and exit in IDLE. In the File menu, “Close” and “Exit” are now “Close Window” (the current one) and “Exit” is now “Exit IDLE” (by closing all windows). In Shell, “quit()” and “exit()” mean “close Shell”. If there are no other windows, this also exits IDLE.
C API¶
bpo-40170: Remove the
PyHeapType_GET_MEMBERS()
macro. It was exposed in the public C API by mistake, it must only be used by Python internally. Use thePyTypeObject.tp_members
member instead. Patch by Victor Stinner.bpo-40170: Move _Py_GetAllocatedBlocks() and _PyObject_DebugMallocStats() private functions to the internal C API. Patch by Victor Stinner.
bpo-46433: The internal function _PyType_GetModuleByDef now correctly handles inheritance patterns involving static types.
bpo-45459:
Py_buffer
and variousPy_buffer
related functions are now part of the limited API and stable ABI.bpo-14916: Fixed bug in the tokenizer that prevented
PyRun_InteractiveOne
from parsing from the provided FD.
Python 3.11.0 alpha 4¶
Release date: 2022-01-13
Core and Builtins¶
bpo-46070:
Py_EndInterpreter()
now explicitly untracks all objects currently tracked by the GC. Previously, if an object was used later by another interpreter, callingPyObject_GC_UnTrack()
on the object crashed if the previous or the next object of thePyGC_Head
structure became a dangling pointer. Patch by Victor Stinner.bpo-46347: Fix memory leak in PyEval_EvalCodeEx.
bpo-46339: Fix a crash in the parser when retrieving the error text for multi-line f-strings expressions that do not start in the first line of the string. Patch by Pablo Galindo
bpo-46331: Do not set line number of instruction storing doc-string. Fixes regression introduced in 3.11 alpha.
bpo-46314: Remove spurious «call» event when creating a lambda function that was accidentally introduced in 3.11a4.
bpo-46289: ASDL declaration of
FormattedValue
has changed to reflectconversion
field is not optional.bpo-46297: Fixed an interpreter crash on bootup with multiple PythonPaths set in the Windows registry. Patch by Derzsi Dániel.
bpo-46237: Fix the line number of tokenizer errors inside f-strings. Patch by Pablo Galindo.
bpo-46263: We always expect the «use_frozen_modules» config to be set, now that getpath.c was rewritten in pure Python and the logic improved.
bpo-46006: Fix a regression when a type method like
__init__()
is modified in a subinterpreter. Fix a regression in_PyUnicode_EqualToASCIIId()
and typeupdate_slot()
. Revert the change which made the Unicode dictionary of interned strings compatible with subinterpreters: the internal interned dictionary is shared again by all interpreters. Patch by Victor Stinner.bpo-45923: Add RESUME opcode. This is a logical no-op. It is emitted by the compiler anywhere a Python function can be entered. It is used by the interpreter to perform tracing and optimizer checks.
bpo-46208: Fix the regression of os.path.normpath(«A/../../B») not returning expected «../B» but «B».
bpo-46240: Correct the error message for unclosed parentheses when the tokenizer doesn’t reach the end of the source when the error is reported. Patch by Pablo Galindo
bpo-46009: Remove the
GEN_START
opcode.bpo-46235: Certain sequence multiplication operations like
[0] * 1_000
are now faster due to reference-counting optimizations. Patch by Dennis Sweeney.bpo-46221:
PREP_RERAISE_STAR
no longer pusheslasti
to the stack.bpo-46202: Remove
POP_EXCEPT_AND_RERAISE
and replace it by an equivalent sequence of other opcodes.bpo-46085: Fix iterator cache mechanism of
OrderedDict
.bpo-46055: Speed up shifting operation involving integers less than
PyLong_BASE
. Patch by Xinhang Xu.bpo-46110: Add a maximum recursion check to the PEG parser to avoid stack overflow. Patch by Pablo Galindo
bpo-46107: Fix bug where
ExceptionGroup.split()
andExceptionGroup.subgroup()
did not copy the exception group’s__note__
field to the parts.bpo-45711: The interpreter state’s representation of handled exceptions (a.k.a exc_info, or _PyErr_StackItem) now has only the
exc_value
field,exc_type
andexc_traceback
have been removed as their values can be derived fromexc_value
.bpo-44525: Replace the four call bytecode instructions which one pre-call instruction and two call instructions.
Removes
CALL_FUNCTION
,CALL_FUNCTION_KW
,CALL_METHOD
andCALL_METHOD_KW
.Adds
CALL_NO_KW
andCALL_KW
call instructions, andPRECALL_METHOD
prefix for pairing withLOAD_METHOD
.bpo-46039: Remove the
YIELD_FROM
instruction and replace it with theSEND
instruction which performs the same operation, but without the loop.bpo-45635: The code called from
_PyErr_Display()
was refactored to improve error handling. It now exits immediately upon an unrecoverable error.bpo-46054: Fix parser error when parsing non-utf8 characters in source files. Patch by Pablo Galindo.
bpo-46042: Improve the location of the caret in
SyntaxError
exceptions emitted by the symbol table. Patch by Pablo Galindo.bpo-46049: Ensure
._pth
files work as intended on platforms other than Windows.bpo-46048: Fixes parsing of
._pth
files on startup so that single-character paths are correctly read.bpo-37971: Fix a bug where the line numbers given in a traceback when a decorator application raised an exception were wrong.
bpo-46031: Add
POP_JUMP_IF_NOT_NONE
andPOP_JUMP_IF_NONE
opcodes to speed up conditional jumps.bpo-46025: Fix a crash in the
atexit
module involving functions that unregister themselves before raising exceptions. Patch by Pablo Galindo.bpo-46000: Improve compatibility of the
curses
module with NetBSD curses.bpo-44525: Specialize the CALL_FUNCTION instruction for calls to builtin types with a single argument. Speeds up
range(x)
,list(x)
, and specificallytype(obj)
.bpo-42918: Fix bug where the built-in
compile()
function did not always raise aSyntaxError
when passed multiple statements in “single” mode. Patch by Weipeng Hong.bpo-45953: The main interpreter in _PyRuntimeState.interpreters is now statically allocated (as part of _PyRuntime). Likewise for the initial thread state of each interpreter. This means less allocation during runtime init, as well as better memory locality for these key state objects.
bpo-45292: Complete the PEP 654 implementation: add
except*
.bpo-43413: Revert changes in
set.__init__
. Subclass ofset
needs to define a__init__()
method if it defines a__new__()
method with additional keyword parameters.bpo-43931: Added the
Py_Version
constant which bears the same value asPY_VERSION_HEX
. Patch by Gabriele N. Tornetta.
Library¶
bpo-46342: The
@typing.final
decorator now sets the__final__
attribute on the decorated object to allow runtime introspection. Patch by Jelle Zijlstra.bpo-46328: Added the
sys.exception()
method which returns the active exception instance.bpo-46307: Add
string.Template.is_valid()
andstring.Template.get_identifiers()
methods.bpo-46306: Assume that
types.CodeType
always hastypes.CodeType.co_firstlineno
indoctest
.bpo-40479: Fix
hashlib
usedforsecurity option to work correctly with OpenSSL 3.0.0 in FIPS mode.bpo-46070: Fix possible segfault when importing the
asyncio
module from different sub-interpreters in parallel. Patch by Erlend E. Aasland.bpo-46244: Removed
__slots__
fromtyping.ParamSpec
andtyping.TypeVar
. They served no purpose. Patch by Arie Bovenberg.bpo-46278: Reflect
context
argument inAbstractEventLoop.call_*()
methods. Loop implementations already support it.bpo-46269: Remove special-casing of
__new__
inenum.Enum.__dir__()
.bpo-46266: Improve day constants in
calendar
.Now all constants (
MONDAY
…SUNDAY
) are documented, tested, and added to__all__
.bpo-46257: Optimized the mean, variance, and stdev functions in the statistics module. If the input is an iterator, it is consumed in a single pass rather than eating memory by conversion to a list. The single pass algorithm is about twice as fast as the previous two pass code.
bpo-41011: Added two new variables to pyvenv.cfg which is generated by
venv
module: executable for the executable and command for the command line used to create the environment.bpo-46239: Improve error message when importing
asyncio.windows_events
on non-Windows.bpo-46238: Reuse
_winapi
constants inasyncio.windows_events
.bpo-46222: Adding
SF_NOCACHE
sendfile constant for FreeBSD for the posixmodule.bpo-37295: Add fast path for
0 <= k <= n <= 67
formath.comb()
.bpo-46176: Adding the
MAP_STACK
constant for the mmap module.bpo-43424: Deprecate
webbrowser.MacOSXOSAScript._name
and usename
instead.bpo-45321: Added missing error codes to module
xml.parsers.expat.errors
.bpo-46125: Refactor tests to test traversable API directly. Includes changes from importlib 5.4.0.
bpo-46118: Moved importlib.resources and its related functionality to a package.
bpo-37578: Add include_hidden parameter to
glob()
andiglob()
to match hidden files and directories when using special characters like*
,**
,?
and[]
.bpo-20369:
concurrent.futures.wait()
no longer blocks forever when given duplicate Futures. Patch by Kumar Aditya.bpo-46105: Honor spec when generating requirement specs with urls and extras (importlib_metadata 4.8.3).
bpo-44893: EntryPoint objects are no longer tuples. Recommended means to access is by attribute (“.name”, “.group”) or accessor (“.load()”). Access by index is deprecated and will raise deprecation warning.
bpo-22815: Print unexpected successes together with failures and errors in summary in
unittest.TextTestResult
.bpo-22047: Calling
add_argument_group()
on an argument group is deprecated. Callingadd_argument_group()
oradd_mutually_exclusive_group()
on a mutually exclusive group is deprecated.These features were never supported and do not always work correctly. The functions exist on the API by accident through inheritance and will be removed in the future.
bpo-26952:
argparse
raisesValueError
with clear message when trying to render usage for an empty mutually exclusive group. Previously it raised a crypticIndexError
.bpo-45615: Functions in the
traceback
module raiseTypeError
rather thanAttributeError
when an exception argument is not of typeBaseException
.bpo-16594: Add allow allow_reuse_port flag in socketserver.
bpo-27718: Fix help for the
signal
module. Some functions (e.g.signal()
andgetsignal()
) were omitted.bpo-46032: The
registry()
method offunctools.singledispatch()
functions checks now the first argument or the first parameter annotation and raises a TypeError if it is not supported. Previously unsupported «types» were ignored (e.g.typing.List[int]
) or caused an error at calling time (e.g.list[int]
).bpo-46014: Add ability to use
typing.Union
andtypes.UnionType
as dispatch argument tofunctools.singledispatch
. Patch provided by Yurii Karabas.bpo-46018: Ensure that
math.expm1()
does not raise on underflow.bpo-46016: Adding
F_DUP2FD
andF_DUP2FD_CLOEXEC
constants from FreeBSD into the fcntl module.bpo-45755:
typing
generic aliases now reveal the class attributes of the original generic class when passed todir()
. This was the behavior up to Python 3.6, but was changed in 3.7-3.9.bpo-45874: The empty query string, consisting of no query arguments, is now handled correctly in
urllib.parse.parse_qsl
. This caused problems before when strict parsing was enabled.bpo-44674: Change how dataclasses disallows mutable default values. It used to use a list of known types (list, dict, set). Now it disallows unhashable objects to be defaults. It’s using unhashability as a proxy for mutability. Patch by Eric V. Smith, idea by Raymond Hettinger.
bpo-23882: Remove namespace package (PEP 420) support from unittest discovery. It was introduced in Python 3.4 but has been broken since Python 3.7.
bpo-25066: Added a
__repr__()
method tomultiprocessing.Event
objects, patch by Kumar Aditya.bpo-45643: Added
signal.SIGSTKFLT
on platforms where this signal is defined.bpo-44092: Fetch across rollback no longer raises
InterfaceError
. Instead we leave it to the SQLite library to handle these cases. Patch by Erlend E. Aasland.bpo-42413: Replace
concurrent.futures.TimeoutError
andasyncio.TimeoutError
with builtinTimeoutError
, keep these names as deprecated aliases.
Documentation¶
Tests¶
bpo-46296: Add a test case for
enum
with_use_args_ == True
and_member_type_ == object
.bpo-46205: Fix hang in runtest_mp due to race condition
bpo-46263: Fix test_capi on FreeBSD 14-dev: instruct jemalloc to not fill freed memory with junk byte.
bpo-46262: Cover
ValueError
path in tests forenum.Flag._missing_()
.bpo-46150: Now
fakename
intest_pathlib.PosixPathTest.test_expanduser
is checked to be non-existent.bpo-46129: Rewrite
asyncio.locks
tests withunittest.IsolatedAsyncioTestCase
usage.bpo-23819: Fixed
asyncio
tests in python optimized mode. Patch by Kumar Aditya.bpo-46114: Fix test case for OpenSSL 3.0.1 version. OpenSSL 3.0 uses
0xMNN00PP0L
.
Build¶
bpo-44133: When Python is configured with
--without-static-libpython
, the Python static library (libpython.a) is no longer built. Patch by Victor Stinner.bpo-44133: When Python is built without
--enable-shared
, thepython
program is now linked to object files, rather than being linked to the Python static library (libpython.a), to make sure that all symbols are exported. Previously, the linker omitted some symbols like thePy_FrozenMain()
function. Patch by Victor Stinner.bpo-40280: The
configure
script has a new option--with-emscripten-target
to select browser or node as Emscripten build target.bpo-46315: Added and fixed
#ifdef HAVE_FEATURE
checks for functionality that is not available on WASI platform.bpo-45723: Fixed a regression in
configure
check forselect.epoll()
.bpo-46263:
configure
no longer setsMULTIARCH
on FreeBSD platforms.bpo-46106: Updated OpenSSL to 1.1.1m in Windows builds, macOS installer builds, and CI. Patch by Kumar Aditya.
bpo-46088: Automatically detect or install bootstrap Python runtime when building from Visual Studio.
bpo-46072: Add a –with-pystats configure option to turn on internal statistics gathering.
bpo-40280: A new directory
Tools/wasm
contains WebAssembly-related helpers likeconfig.site
override for wasm32-emscripten, wasm assets generator to bundle the stdlib, and a README.bpo-46023: makesetup no longer builds extensions that have been marked as disabled. This allows users to disable modules in
Modules/Setup.local
.bpo-45949: Use pure Python
freeze_module
for all but importlib bootstrap files.--with-freeze-module
configure option is no longer needed for cross builds.
Windows¶
bpo-46217: Removed parameter that is unsupported on Windows 8.1 and early Windows 10 and may have caused build or runtime failures.
macOS¶
bpo-40477: The Python Launcher app for macOS now properly launches scripts and, if necessary, the Terminal app when running on recent macOS releases.
C API¶
bpo-46236: Fix a bug in
PyFunction_GetAnnotations()
that caused it to return atuple
instead of adict
.bpo-46140:
PyBuffer_GetPointer()
,PyBuffer_FromContiguous()
,PyBuffer_ToContiguous()
andPyMemoryView_FromBuffer()
now take buffer info byconst Py_buffer *
instead ofPy_buffer *
, as they do not need mutability.PyBuffer_FromContiguous()
also now takes the source buffer asconst void *
, and similarlyPyBuffer_GetPointer()
takes the strides asconst Py_ssize_t *
.bpo-45855: Document that the no_block argument to
PyCapsule_Import()
is a no-op now.bpo-45855: Replaced deprecated usage of
PyImport_ImportModuleNoBlock()
withPyImport_ImportModule()
in stdlib modules. Patch by Kumar Aditya.bpo-46007: The
PyUnicode_CHECK_INTERNED()
macro has been excluded from the limited C API. It was never usable there, because it used internal structures which are not available in the limited C API. Patch by Victor Stinner.
Python 3.11.0 alpha 3¶
Release date: 2021-12-08
Core and Builtins¶
bpo-46009: Restore behavior from 3.9 and earlier when sending non-None to newly started generator. In 3.9 this did not affect the state of the generator. In 3.10.0 and 3.10.1
gen_func().send(0)
is equivalent togen_func().throw(TypeError(...)
which exhausts the generator. In 3.10.2 onward, the behavior has been reverted to that of 3.9.bpo-46004: Fix the
SyntaxError
location for errors involving for loops with invalid targets. Patch by Pablo Galindobpo-45711:
_PyErr_ChainStackItem()
no longer normalizesexc_info
(including setting the traceback on the exception instance) becauseexc_info
is always normalized.bpo-45607: The
__note__
field was added toBaseException
. It isNone
by default but can be set to a string which is added to the exception’s traceback.bpo-45947: Place pointers to dict and values immediately before GC header. This reduces number of dependent memory loads to access either dict or values from 3 to 1.
bpo-45915:
is_valid_fd
now uses fasterfcntl(fd, F_GETFD)
on Linux, macOS, and Windows.bpo-44530: Reverts a change to the
code.__new__
audit event from an earlier prerelease.bpo-42268: Fail the configure step if the selected compiler doesn’t support memory sanitizer. Patch by Pablo Galindo
bpo-45711: The three values of
exc_info
are now always consistent with each other. In particular, thetype
andtraceback
fields are now derived from the exception instance. This impacts the return values ofsys.exc_info()
andPyErr_GetExcInfo()
if the exception instance is modified while the exception is handled, as well asPyErr_SetExcInfo()
, which now ignores thetype
andtraceback
arguments provided to it.bpo-45727: Refine the custom syntax error that suggests that a comma may be missing to trigger only when the expressions are detected between parentheses or brackets. Patch by Pablo Galindo
bpo-45885: Specialized the
COMPARE_OP
opcode using the PEP 659 machinery.bpo-45786: Allocate space for the interpreter frame in the frame object, to avoid an additional allocation when the frame object outlives the frame activation.
bpo-45614: Fix
traceback
display for exceptions with invalid module name.bpo-45813: Fix crash when calling coro.cr_frame.clear() after coroutine has been freed.
bpo-45811: Improve the tokenizer errors when encountering invisible control characters in the parser. Patch by Pablo Galindo
bpo-45848: Allow the parser to obtain error lines directly from encoded files. Patch by Pablo Galindo
bpo-45709: Restore behavior from 3.10 when tracing an exception raised within a with statement.
bpo-44525: Adds new
COPY_FREE_VARS
opcode, to make copying of free variables from function to frame explicit. Helps optimization of calls to Python function.bpo-45829: Specialize
BINARY_SUBSCR
for classes with a__getitem__
method implemented in Pythonbpo-45826: Fixed a crash when calling
.with_traceback(None)
onNameError
. This occurs internally inunittest.TestCase.assertRaises()
.bpo-45822: Fixed a bug in the parser that was causing it to not respect PEP 263 coding cookies when no flags are provided. Patch by Pablo Galindo
bpo-45820: Fix a segfault when the parser fails without reading any input. Patch by Pablo Galindo
bpo-45636: Simplify the implementation of
BINARY_OP
by indexing into an array of function pointers (rather than switching on the oparg).bpo-42540: Fix crash when
os.fork()
is called with an active non-default memory allocator.bpo-45738: Fix computation of error location for invalid continuation characters in the parser. Patch by Pablo Galindo.
bpo-45636: Remove an existing «fast path» for old-style string formatting, since it no longer appears to have any measurable impact.
bpo-45753: Make recursion checks a bit more efficient by tracking amount of calls left before overflow.
bpo-45773: Fix a compiler hang when attempting to optimize certain jump patterns.
bpo-45764: The parser now gives a better error message when leaving out the opening parenthesis
(
after adef
-statement:>>> def f: File "<stdin>", line 1 def f: ^ SyntaxError: expected '('
bpo-45609: Specialized the
STORE_SUBSCR
opcode using the PEP 659 machinery.bpo-45636: Replace all numeric
BINARY_*
andINPLACE_*
instructions with a singleBINARY_OP
implementation.bpo-45582: Path calculation (known as
getpath
) has been reimplemented as a frozen Python module. This should have no visible impact, but may affect calculation of all paths referenced insys
andsysconfig
.bpo-45450: Improve the syntax error message for parenthesized arguments. Patch by Pablo Galindo.
Library¶
bpo-27946: Fix possible crash when getting an attribute of class:
xml.etree.ElementTree.Element
simultaneously with replacing theattrib
dict.bpo-45711: Make
asyncio
normalize exceptions as soon as they are captured withPyErr_Fetch()
, and before they are stored as an exc_info triplet. This bringsasyncio
in line with the rest of the codebase, where an exc_info triplet is always normalized.bpo-23819: Replaced asserts with exceptions in asyncio, patch by Kumar Aditya.
bpo-13236:
unittest.TextTestResult
andunittest.TextTestRunner
flush now the output stream more often.bpo-45917: Added
math.exp2()
:, which returns 2 raised to the power of x.bpo-37658: Fix issue when on certain conditions
asyncio.wait_for()
may allow a coroutine to complete successfully, but fail to return the result, potentially causing memory leaks or other issues.bpo-45876: Improve the accuracy of stdev() and pstdev() in the statistics module. When the inputs are floats or fractions, the output is a correctly rounded float
bpo-44649: Handle dataclass(slots=True) with a field that has default a default value, but for which init=False.
bpo-45803: Added missing kw_only parameter to dataclasses.make_dataclass().
bpo-45837: The
turtle.RawTurtle.settiltangle()
is deprecated since Python 3.1, it now emits a deprecation warning and will be removed in Python 3.13.Use
turtle.RawTurtle.tiltangle()
instead.turtle.RawTurtle.tiltangle()
was earlier incorrectly marked as deprecated, its docstring has been corrected.Patch by Hugo van Kemenade.
bpo-45831:
faulthandler
can now write ASCII-only strings (like filenames and function names) with a single write() syscall when dumping a traceback. It reduces the risk of getting an unreadable dump when two threads or two processes dump a traceback to the same file (like stderr) at the same time. Patch by Victor Stinner.bpo-45828:
sqlite
C callbacks now use unraisable exceptions if callback tracebacks are enabled. Patch by Erlend E. Aasland.bpo-41735: Fix thread lock in
zlib.Decompress.flush()
method beforePyObject_GetBuffer
.bpo-45235: Reverted an argparse bugfix that caused regression in the handling of default arguments for subparsers. This prevented leaf level arguments from taking precedence over root level arguments.
bpo-45754: Fix a regression in Python 3.11a1 and 3.11a2 where
sqlite3
incorrectly would useSQLITE_LIMIT_LENGTH
when checking SQL statement lengths. Now,SQLITE_LIMIT_SQL_LENGTH
is used. Patch by Erlend E. Aasland.bpo-45766: Added proportional option to
statistics.linear_regression()
.bpo-45765: In importlib.metadata, fix distribution discovery for an empty path.
bpo-45757: Fix bug where
dis
produced an incorrect oparg whenEXTENDED_ARG
is followed by an opcode that does not use its argument.bpo-45644: In-place JSON file formatting using
python3 -m json.tool infile infile
now works correctly, previously it left the file empty. Patch by Chris Wesseling.bpo-45703: When a namespace package is imported before another module from the same namespace is created/installed in a different
sys.path
location while the program is running, calling theimportlib.invalidate_caches()
function will now also guarantee the new module is noticed.bpo-45535: Improve output of
dir()
with Enums.bpo-45664: Fix
types.resolve_bases()
andtypes.new_class()
fortypes.GenericAlias
instance as a base.bpo-45663: Fix
dataclasses.is_dataclass()
for dataclasses which are subclasses oftypes.GenericAlias
.bpo-45662: Fix the repr of
dataclasses.InitVar
with a type alias to the built-in class, e.g.InitVar[list[int]]
.bpo-43137: Launch GNOME web browsers via gio tool instead of obsolete gvfs-open
bpo-45429: On Windows,
time.sleep()
now uses a waitable timer which supports high-resolution timers. Patch by Dong-hee Na and Eryk Sun.bpo-37295: Optimize
math.comb()
andmath.perm()
.bpo-45514: Deprecated legacy functions in
importlib.resources
.bpo-45507: Add tests for truncated/missing trailers in gzip.decompress implementation.
bpo-45359: Implement PEP 585 for
graphlib.TopologicalSorter
.bpo-44733: Add
max_tasks_per_child
toconcurrent.futures.ProcessPoolExecutor
. This allows users to specify the maximum number of tasks a single process should execute before the process needs to be restarted.bpo-28806: Improve netrc library. netrc file no longer needs to contain all tokens. And if the login name is anonymous, security check is no longer need.
bpo-43498: Avoid a possible «RuntimeError: dictionary changed size during iteration» when adjusting the process count of
ProcessPoolExecutor
.bpo-42158: Add MIME types for N-quads, N-triples, Notation3 and TriG to
mimetypes
.bpo-30533: Add
inspect.getmembers_static()
, it return all members without triggering dynamic lookup via the descriptor protocol. Patch by Weipeng Hong.
Documentation¶
bpo-42238:
make -C Doc suspicious
will be removed soon in favor ofmake -C Doc check
, mark it as deprecated.bpo-45840: Improve cross-references in the documentation for the data model.
bpo-45640: Properly marked-up grammar tokens in the documentation are now clickable and take you to the definition of a given piece of grammar. Patch by Arthur Milchior.
bpo-45788: Link doc for sys.prefix to sysconfig doc on installation paths.
bpo-45772:
socket.socket
documentation is corrected to a class from a function.bpo-45392: Update the docstring of the
type
built-in to remove a redundant line and to mention keyword arguments for the constructor.bpo-45250: Update the documentation to note that CPython does not consistently require iterators to define
__iter__
.bpo-25381: In the extending chapter of the extending doc, update a paragraph about the global variables containing exception information.
bpo-43905: Expanded
astuple()
andasdict()
docs, warning about deepcopy being applied and providing a workaround.
Tests¶
bpo-45695: Out-of-tree builds with a read-only source directory are now tested by CI.
bpo-19460: Add new Test for
Lib/email/mime/nonmultipart.py::MIMENonMultipart
.bpo-45835: Fix race condition in test_queue tests with multiple «feeder» threads.
bpo-45783: The test for the freeze tool now handles file moves and deletions.
bpo-45745: Remove the
--findleaks
command line option of regrtest: use the--fail-env-changed
option instead. Since Python 3.7, it was a deprecated alias to the--fail-env-changed
option.bpo-45701: Add tests with
tuple
type withfunctools.lru_cache()
totest_functools
.
Build¶
bpo-44035: CI now verifies that autoconf files have been regenerated with a current and unpatched autoconf package.
bpo-45950: The build system now uses a _bootstrap_python interpreter for freezing and deepfreezing again. To speed up build process the build tools _bootstrap_python and _freeze_module are no longer build with LTO.
bpo-45881: The configure script now accepts
--with-build-python
and--with-freeze-module
options to make cross compiling easier.bpo-40280: Emscripten platform now uses
.wasm
suffix by default.bpo-40280: Disable unusable core extension modules on WASM/Emscripten targets.
bpo-40280:
configure
now checks for socketshutdown
function. The check makes it possible to disableSYS_shutdown
withac_cv_func_shutdown=no
in CONFIG_SITE.bpo-40280:
configure
now checks for functionsfork1, getegid, geteuid, getgid, getppid, getuid, opendir, pipe, system, wait, ttyname
.bpo-33393: Update
config.guess
to 2021-06-03 andconfig.sub
to 2021-08-14.Makefile
now has anupdate-config
target to make updating more convenient.bpo-45866:
make regen-all
now produces the same output when run from a directory other than the source tree: when building Python out of the source tree. pegen now strips directory of the «generated by pygen from <FILENAME>» header Patch by Victor Stinner.bpo-40280:
configure
now accepts machinewasm32
orwasm64
and OSwasi
oremscripten
for cross building, e.g.wasm32-unknown-emscripten
,wasm32-wasi
, orwasm32-unknown-wasi
.bpo-41498: Python now compiles on platforms without
sigset_t
. Several functions insignal
are not available whensigset_t
is missing.Based on patch by Roman Yurchak for pyodide.
bpo-45881:
setup.py
now usesCC
from environment first to discover multiarch and cross compile paths.bpo-45886: The
_freeze_module
program path can now be overridden on the command line, e.g.make FREEZE_MODULE=../x86_64/Program/_freeze_module
.bpo-45873: Get rid of the
_bootstrap_python
build step. The deepfreeze.py script is now run using$(PYTHON_FOR_REGEN)
which can be Python 3.7 or newer (on Windows, 3.8 or newer).bpo-45847: Port builtin hashlib extensions to
PY_STDLIB_MOD
macro andaddext()
.bpo-45723: Add
autoconf
helpers for saving and restoring environment variables:SAVE_ENV
: Save$CFLAGS
,$LDFLAGS
,$LIBS
, and$CPPFLAGS
.RESTORE_ENV
: Restore$CFLAGS
,$LDFLAGS
,$LIBS
, and$CPPFLAGS
.WITH_SAVE_ENV([SCRIPT])
: RunSCRIPT
wrapped withSAVE_ENV
andRESTORE_ENV
.
Patch by Erlend E. Aasland.
bpo-45573: Mandatory core modules, that are required to bootstrap Python, are now in
Modules/Setup.bootstrap
.bpo-45573:
configure
now createsModules/Setup.stdlib
with conditionally enabled/disabled extension module lines. The file is not used, yet.bpo-45573:
configure
now uses a unified format to set state, compiler flags, and linker flags in Makefile. The new macroPY_STDLIB_MOD
sets three variables that are consumed byModules/Setup
andsetup.py
.bpo-45816: Python now supports building with Visual Studio 2022 (MSVC v143, VS Version 17.0). Patch by Jeremiah Vivian.
bpo-45800: Settings for
pyexpat
C extension are now detected byconfigure
. The bundledexpat
library is built inMakefile
.bpo-45798: Settings for
decimal
internal C extension are now detected byconfigure
. The bundledlibmpdec
library is built inMakefile
.bpo-45723: configure has a new option
--with-pkg-config
to disable or require pkg-config.bpo-45774: The build dependencies for
sqlite3
are now detected byconfigure
andpkg-config
. Patch by Erlend E. Aasland.bpo-45763: The build dependencies for
zlib
,bz2
, andlzma
are now detected byconfigure
.bpo-45747: gdbm and dbm build dependencies are now detected by
configure
.bpo-45743: On macOS, the build system no longer passes
search_paths_first
to the linker. The flag has been the default since Xcode 4 / macOS 10.6.bpo-45723:
configure.ac
is now compatible with autoconf 2.71. Deprecated checksSTDC_HEADERS
andAC_HEADER_TIME
have been removed.bpo-45723:
configure
now prints a warning when pkg-config is missing.bpo-45731:
configure --enable-loadable-sqlite-extensions
is now handled by newPY_SQLITE_ENABLE_LOAD_EXTENSION
macro instead of logic in setup.py.bpo-45723: configure.ac now uses custom helper macros and
AC_CACHE_CHECK
to simplify and speed up configure runs.bpo-45696: Skip the marshal step for frozen modules by generating C code that produces a set of ready-to-use code objects. This speeds up startup time by another 10% or more.
bpo-45561: Run smelly.py tool from $(srcdir).
Windows¶
bpo-46105: Fixed calculation of
sys.path
in a venv on Windows.bpo-45901: When installed through the Microsoft Store and set as the default app for
*.py
files, command line arguments will now be passed to Python when invoking a script without explicitly launching Python (that is,script.py args
rather thanpython script.py args
).bpo-45616: Fix Python Launcher’s ability to distinguish between versions 3.1 and 3.10 when either one is explicitly requested. Previously, 3.1 would be used if 3.10 was requested but not installed, and 3.10 would be used if 3.1 was requested but 3.10 was installed.
bpo-45850: Implement changes to build with deep-frozen modules on Windows. Note that we now require Python 3.10 as the «bootstrap» or «host» Python.
bpo-45732: Updates bundled Tcl/Tk to 8.6.12.
bpo-45720: Internal reference to
shlwapi.dll
was dropped to help improve startup time. This DLL will no longer be loaded at the start of every Python process.
macOS¶
bpo-45732: Update python.org macOS installer to use Tcl/Tk 8.6.12.
C API¶
bpo-39026: Fix Python.h to build C extensions with Xcode: remove a relative include from
Include/cpython/pystate.h
.
Python 3.11.0 alpha 2¶
Release date: 2021-11-05
Core and Builtins¶
bpo-45716: Improve the
SyntaxError
message when usingTrue
,None
orFalse
as keywords in a function call. Patch by Pablo Galindo.bpo-45688:
sys.stdlib_module_names
now contains the macOS-specific module_scproxy
.bpo-45379: Clarify
ImportError
message when we try to explicitly import a frozen module but frozen modules are disabled.bpo-44525: Specialize simple calls to Python functions (no starargs, keyowrd dict, or closure)
bpo-45530: Cases of sorting using tuples as keys may now be significantly faster in some cases. Patch by Tim Peters.
The order of the result may differ from earlier releases if the tuple elements don’t define a total ordering (see Comparaciones de valor for information on total ordering). It’s generally true that the result of sorting simply isn’t well-defined in the absence of a total ordering on list elements.
bpo-45526: In obmalloc, set ADDRESS_BITS to not ignore any bits (ignored 16 before). That is safer in the case that the kernel gives user-space virtual addresses that span a range greater than 48 bits.
bpo-30570: Fixed a crash in
issubclass()
from infinite recursion when searching pathological__bases__
tuples.bpo-45521: Fix a bug in the obmalloc radix tree code. On 64-bit machines, the bug causes the tree to hold 46-bits of virtual addresses, rather than the intended 48-bits.
bpo-45494: Fix parser crash when reporting errors involving invalid continuation characters. Patch by Pablo Galindo.
bpo-45445: Python now fails to initialize if it finds an invalid
-X
option in the command line. Patch by Pablo Galindo.bpo-45340: Object attributes are held in an array instead of a dictionary. An object’s dictionary are created lazily, only when needed. Reduces the memory consumption of a typical Python object by about 30%. Patch by Mark Shannon.
bpo-45408: Fix a crash in the parser when reporting tokenizer errors that occur at the same time unclosed parentheses are detected. Patch by Pablo Galindo.
bpo-29410: Add SipHash13 for string hash algorithm and use it by default.
bpo-45385: Fix reference leak from descr_check. Patch by Dong-hee Na.
bpo-45367: Specialized the
BINARY_MULTIPLY
opcode toBINARY_MULTIPLY_INT
andBINARY_MULTIPLY_FLOAT
using the PEP 659 machinery.bpo-21736: Frozen stdlib modules now have
__file__
to the .py file they would otherwise be loaded from, if possible. For packages,__path__
now has the correct entry instead of being an empty list, which allows unfrozen submodules to be imported. These are set only if the stdlib directory is known when the runtime is initialized. Note that the file at__file__
is not guaranteed to exist. None of this affects non-stdlib frozen modules nor, for now, frozen modules imported usingPyImport_ImportFrozenModule()
. Also, at the momentco_filename
is not updated for the module.bpo-45020: For frozen stdlib modules, record the original module name as
module.__spec__.loader_state.origname
. If the value is different thanmodule.__spec__.name
then the module was defined as an alias in Tools/scripts/freeze_modules.py. If it isNone
then the module comes from a source file outside the stdlib.bpo-45324: In FrozenImporter.find_spec(), we now preserve the information needed in exec_module() to load the module. This change mostly impacts internal details, rather than changing the importer’s behavior.
bpo-45292: Implement PEP 654. Add
ExceptionGroup
andBaseExceptionGroup
. Update traceback display code.bpo-40116: Change to the implementation of split dictionaries. Classes where the instances differ either in the exact set of attributes, or in the order in which those attributes are set, can still share keys. This should have no observable effect on users of Python or the C-API. Patch by Mark Shannon.
bpo-44050: Extensions that indicate they use global state (by setting
m_size
to -1) can again be used in multiple interpreters. This reverts to behavior of Python 3.8.bpo-44525: Setup initial specialization infrastructure for the
CALL_FUNCTION
opcode. Implemented initial specializations for C function calls:CALL_FUNCTION_BUILTIN_O
forMETH_O
flag.CALL_FUNCTION_BUILTIN_FAST
forMETH_FASTCALL
flag without keywords.CALL_FUNCTION_LEN
forlen(o)
.CALL_FUNCTION_ISINSTANCE
forisinstance(o, t)
.
bpo-44511: Improve the generated bytecode for class and mapping patterns.
bpo-43706: Speed up calls to
enumerate()
by using the PEP 590vectorcall
calling convention. Patch by Dong-hee Na.
Library¶
bpo-45679: Fix caching of multi-value
typing.Literal
.Literal[True, 2]
is no longer equal toLiteral[1, 2]
.bpo-42064: Convert
sqlite3
to multi-phase initialisation (PEP 489). Patches by Erlend E. Aasland.bpo-45438: Fix typing.Signature string representation for generic builtin types.
bpo-45613:
sqlite3
now setssqlite3.threadsafety
based on the default threading mode the underlying SQLite library has been compiled with. Patch by Erlend E. Aasland.bpo-45574: Fix warning about
print_escape
being unused.bpo-45581:
sqlite3.connect()
now correctly raisesMemoryError
if the underlying SQLite API signals memory error. Patch by Erlend E. Aasland.bpo-45557: pprint.pprint() now handles underscore_numbers correctly. Previously it was always setting it to False.
bpo-44019: Add
operator.call()
tooperator.__all__
. Patch by Kreusada.bpo-42174:
shutil.get_terminal_size()
now falls back to sane values if the column or line count are 0.bpo-35673: Improve the introspectability of the
__loader__
attribute for namespace packages.importlib.machinery.NamespaceLoader
is now public, and implements theimportlib.abc.InspectLoader
interface._NamespaceLoader
is kept for backward compatibility.bpo-45515: Add references to
zoneinfo
in thedatetime
documentation, mostly replacing outdated references todateutil.tz
. Change by Paul Ganssle.bpo-45475: Reverted optimization of iterating
gzip.GzipFile
,bz2.BZ2File
, andlzma.LZMAFile
(see bpo-43787) because it caused regression when user iterate them without having reference of them. Patch by Inada Naoki.bpo-45489: Update
ForwardRef
to support|
operator. Patch by Dong-hee Na.bpo-42222: Removed deprecated support for float arguments in randrange().
bpo-45428: Fix a regression in py_compile when reading filenames from standard input.
bpo-45467: Fix incremental decoder and stream reader in the «raw-unicode-escape» codec. Previously they failed if the escape sequence was split.
bpo-45461: Fix incremental decoder and stream reader in the «unicode-escape» codec. Previously they failed if the escape sequence was split.
bpo-45239: Fixed
email.utils.parsedate_tz()
crashing withUnboundLocalError
on certain invalid input instead of returningNone
. Patch by Ben Hoyt.bpo-45417: Fix quadratic behaviour in the enum module: Creation of enum classes with a lot of entries was quadratic.
bpo-45249: Fix the behaviour of
traceback.print_exc()
when displaying the caret when theend_offset
in the exception is set to 0. Patch by Pablo Galindobpo-45416: Fix use of
asyncio.Condition
with explicitasyncio.Lock
objects, which was a regression due to removal of explicit loop arguments. Patch by Joongi Kim.bpo-20028: Empty escapechar/quotechar is not allowed when initializing
csv.Dialect
. Patch by Vajrasky Kok and Dong-hee Na.bpo-44904: Fix bug in the
doctest
module that caused it to fail if a docstring included an example with aclassmethod
property
. Patch by Alex Waygood.bpo-45406: Make
inspect.getmodule()
catchFileNotFoundError
raised by :”func:inspect.getabsfile
, and returnNone
to indicate that the module could not be determined.bpo-45411: Add extensions for files containing subtitles - .srt & .vtt - to the mimetypes.py module.
bpo-10716: Migrated pydoc to HTML5 (without changing the look of it). Side effect is to update xmlrpc’s
ServerHTMLDoc
which now uses the CSS too. cgitb now relies less on pydoc (as it can’t use the CSS file).bpo-45262: Prevent use-after-free in asyncio. Make sure the cached running loop holder gets cleared on dealloc to prevent use-after-free in get_running_loop
bpo-45386: Make
xmlrpc.client
more robust to C runtimes where the underlying Cstrftime
function results in aValueError
when testing for year formatting options.bpo-20028: Improve error message of
csv.Dialect
when initializing. Patch by Vajrasky Kok and Dong-hee Na.bpo-45343: Update bundled pip to 21.2.4 and setuptools to 58.1.0
bpo-45328: Fixed
http.client.HTTPConnection
to work properly in OSs that don’t support theTCP_NODELAY
socket option.bpo-45243: Add
setlimit()
andgetlimit()
tosqlite3.Connection
for setting and getting SQLite limits by connection basis. Patch by Erlend E. Aasland.bpo-45320: Removed from the
inspect
module:- the
getargspec
function, deprecated since Python 3.0; use
inspect.signature()
orinspect.getfullargspec()
instead.
- the
the
formatargspec
function, deprecated since Python 3.5; use theinspect.signature()
function andSignature
object directly.the undocumented
Signature.from_builtin
andSignature.from_function
functions, deprecated since Python 3.5; use theSignature.from_callable()
method instead.
Patch by Hugo van Kemenade.
bpo-45192: Fix the
tempfile._infer_return_type
function so that thedir
argument of thetempfile
functions accepts an object implementing theos.PathLike
protocol.Patch by Kyungmin Lee.
bpo-45160: When tracing a tkinter variable used by a ttk OptionMenu, callbacks are no longer made twice.
bpo-25625: Added non parallel-safe
chdir()
context manager to change the current working directory and then restore it on exit. Simple wrapper aroundchdir()
.bpo-24139: Add support for SQLite extended result codes in
sqlite3.Error
. Patch by Erlend E. Aasland.bpo-24444: Fixed an error raised in
argparse
help display when help for an option is set to 1+ blank spaces or when choices arg is an empty container.bpo-44547: Implement
Fraction.__int__
, so that afractions.Fraction
instancef
passes anisinstance(f, typing.SupportsInt)
check.bpo-40321: Adds support for HTTP 308 redirects to
urllib
. See RFC 7538 for details. Patch by Jochem Schulenklopper.bpo-41374: Ensure that
socket.TCP_*
constants are exposed on Cygwin 3.1.6 and greater.bpo-35970: Add help flag to the base64 module’s command line interface. Patch contributed by Robert Kuska.
Documentation¶
bpo-45726: Improve documentation for
functools.singledispatch()
andfunctools.singledispatchmethod
.bpo-45680: Amend the docs on
GenericAlias
objects to clarify that non-container classes can also implement__class_getitem__
. Patch contributed by Alex Waygood.bpo-45618: Update Sphinx version used to build the documentation to 4.2.0. Patch by Maciej Olko.
bpo-45655: Add a new «relevant PEPs» section to the top of the documentation for the
typing
module. Patch by Alex Waygood.bpo-45604: Add
level
argument tomultiprocessing.log_to_stderr
function docs.bpo-45516: Add protocol description to the
importlib.abc.TraversableResources
documentation.bpo-45464: Mention in the documentation of Built-in Exceptions that inheriting from multiple exception types in a single subclass is not recommended due to possible memory layout incompatibility.
bpo-45449: Add note about PEP 585 in
collections.abc
.bpo-45516: Add protocol description to the
importlib.abc.Traversable
documentation.bpo-20692: Add Programming FAQ entry explaining that int literal attribute access requires either a space after or parentheses around the literal.
Tests¶
bpo-45678: Add tests for scenarios in which
functools.singledispatchmethod
is stacked on top of a method that has already been wrapped by two other decorators. Patch by Alex Waygood.bpo-45578: Add tests for
dis.distb()
bpo-45678: Add tests to ensure that
functools.singledispatchmethod
correctly wraps the attributes of the target function.bpo-45668: PGO tests now pass when Python is built without test extension modules.
bpo-45577: Add subtests for all
pickle
protocols intest_zoneinfo
.bpo-45566: Fix
test_frozen_pickle
intest_dataclasses
to check allpickle
versions.bpo-43592:
test.libregrtest
now raises the soft resource limit for the maximum number of file descriptors when the default is too low for our test suite as was often the case on macOS.bpo-39679: Add more test cases for
@functools.singledispatchmethod
when combined with@classmethod
or@staticmethod
.bpo-45410: When libregrtest spawns a worker process, stderr is now written into stdout to keep messages order. Use a single pipe for stdout and stderr, rather than two pipes. Previously, messages were out of order which made analysis of buildbot logs harder Patch by Victor Stinner.
bpo-45402: Fix test_tools.test_sundry() when Python is built out of tree: fix how the freeze_modules.py tool locates the _freeze_module program. Patch by Victor Stinner.
bpo-45403: Fix test_sys.test_stdlib_dir() when Python is built outside the source tree: compare normalized paths. Patch by Victor Stinner.
bpo-45400: Fix test_name_error_suggestions_do_not_trigger_for_too_many_locals() of test_exceptions if a directory name contains «a1» (like «Python-3.11.0a1»): use a stricter regular expression. Patch by Victor Stinner.
bpo-10572: Rename
sqlite3
tests fromtest_sqlite
totest_sqlite3
, and relocate them toLib/test/test_sqlite3
. Patch by Erlend E. Aasland.
Build¶
bpo-43158:
setup.py
now uses values from configure script to build the_uuid
extension module. Configure now detects util-linux’slibuuid
, too.bpo-45666: Fix warning of
swprintf
and%s
usage in_testembed.c
bpo-45548:
Modules/Setup
andModules/makesetup
have been improved. TheSetup
file now contains working rules for all extensions. Outdated comments have been removed. Rules defined bymakesetup
track dependencies correctly.bpo-45548: The
math
andcmath
implementation now require a C99 compatiblelibm
and no longer ship with workarounds for missing acosh, asinh, atanh, expm1, and log1p functions.bpo-45595:
setup.py
andmakesetup
now track build dependencies on all Python header files and module specific header files.bpo-45571:
Modules/Setup
now usePY_CFLAGS_NODIST
instead ofPY_CFLAGS
to compile shared modules.bpo-45570:
pyexpat
and_elementtree
no longer define obsolete macrosHAVE_EXPAT_CONFIG_H
andUSE_PYEXPAT_CAPI
.XML_POOR_ENTROPY
is now defined inexpat_config.h
.bpo-43974:
setup.py
no longer definesPy_BUILD_CORE_MODULE
. Instead every module, that uses the internal API, defines the macro.bpo-45548: Fill in missing entries in Modules/Setup.
bpo-45532: Update
sys.version
to usemain
as fallback information. Patch by Jeong YunWon.bpo-45536: The
configure
script now checks whether OpenSSL headers and libraries provide required APIs. Most common APIs are verified. The check detects outdated or missing OpenSSL. Failures do not stop configure.bpo-45221: Fixed regression in handling of
LDFLAGS
andCPPFLAGS
options whereargparse.parse_known_args()
could interpret an option as one of the built-in command line argument, for example-h
for help.bpo-45440: Building Python now requires a C99
<math.h>
header file providing the following functions:copysign()
,hypot()
,isfinite()
,isinf()
,isnan()
,round()
. Patch by Victor Stinner.bpo-45405: Prevent
internal configure error
when runningconfigure
with recent versions of non-Apple clang. Patch by David Bohman.bpo-45433: Avoid linking libpython with libcrypt.
Windows¶
bpo-43652: Update Tcl/Tk to 8.6.11, actually this time. The previous update incorrectly included 8.6.10.
bpo-45337: venv now warns when the created environment may need to be accessed at a different path, due to redirections, links or junctions. It also now correctly installs or upgrades components when the alternate path is required.
bpo-43851: Build SQLite
SQLITE_OMIT_AUTOINIT
on Windows. Patch by Erlend E. Aasland.
macOS¶
bpo-44828: Avoid tkinter file dialog failure on macOS 12 Monterey when using the Tk 8.6.11 provided by python.org macOS installers. Patch by Marc Culler of the Tk project.
IDLE¶
bpo-45495: Add context keywords “case” and “match” to completions list.
C API¶
bpo-29103:
PyType_FromSpec*
now copies the class name from the spec to a buffer owned by the class, so the original can be safely deallocated. Patch by Petr Viktorin.bpo-45522: The internal freelists for frame, float, list, dict, async generators, and context objects can now be disabled.
bpo-35134: Exclude
PyWeakref_GET_OBJECT()
from the limited C API. It never worked since thePyWeakReference
structure is opaque in the limited C API.bpo-35081: Move the
interpreteridobject.h
header file fromInclude/
toInclude/internal/
. It only provides private functions. Patch by Victor Stinner.bpo-35134: The non-limited API files
cellobject.h
,classobject.h
,context.h
,funcobject.h
,genobject.h
andlongintrepr.h
have been moved to theInclude/cpython
directory. Moreover, theeval.h
header file was removed. These files must not be included directly, as they are already included inPython.h
: Include Files. If they have been included directly, consider includingPython.h
instead. Patch by Victor Stinner.bpo-45474: The following items are no longer available when
Py_LIMITED_API
is defined:the
Py_MARSHAL_VERSION
macro
These are not part of the limited API.
Patch by Victor Stinner.
bpo-45434: Remove the
pystrhex.h
header file. It only contains private functions. C extensions should only include the main<Python.h>
header file. Patch by Victor Stinner.bpo-45440: Remove the
Py_FORCE_DOUBLE()
macro. It was used by thePy_IS_INFINITY()
macro. Patch by Victor Stinner.