3.8.0a4 - Cpython — ContextQMD

.. bpo: 36742 .. date: 2019-04-29-15-34-59 .. nonce: QCUY0i .. release date: 2019-05-06 .. section: Security

Fixes mishandling of pre-normalization characters in urlsplit().

.. bpo: 30458 .. date: 2019-04-10-08-53-30 .. nonce: 51E-DA .. section: Security

Address :cve:2019-9740 by disallowing URL paths with embedded whitespace or control characters through into the underlying http client request. Such potentially malicious header injection URLs now cause an http.client.InvalidURL exception to be raised.

.. bpo: 35755 .. date: 2019-01-17-10-03-48 .. nonce: GmllIs .. section: Security

:func:shutil.which now uses os.confstr("CS_PATH") if available and if the :envvar:PATH environment variable is not set. Remove also the current directory from :data:posixpath.defpath. On Unix, :func:shutil.which and the :mod:subprocess module no longer search the executable in the current directory if the :envvar:PATH environment variable is not set.

.. bpo: 36722 .. date: 2019-04-25-21-02-40 .. nonce: 8NApVM .. section: Core and Builtins

In debug build, import now also looks for C extensions compiled in release mode and for C extensions compiled in the stable ABI.

.. bpo: 32849 .. date: 2019-04-16-11-56-12 .. nonce: aeSg-D .. section: Core and Builtins

Fix Python Initialization code on FreeBSD to detect properly when stdin file descriptor (fd 0) is invalid.

.. bpo: 36623 .. date: 2019-04-13-02-08-44 .. nonce: HR_xhB .. section: Core and Builtins

Remove parser headers and related function declarations that lack implementations after the removal of pgen.

.. bpo: 20180 .. date: 2019-04-12-15-49-15 .. nonce: KUqVk7 .. section: Core and Builtins

dict.pop() is now up to 33% faster thanks to Argument Clinic. Patch by Inada Naoki.

.. bpo: 36611 .. date: 2019-04-12-12-32-39 .. nonce: zbo9WQ .. section: Core and Builtins

Debug memory allocators: disable serialno field by default from debug hooks on Python memory allocators to reduce the memory footprint by 5%. Enable :mod:tracemalloc to get the traceback where a memory block has been allocated when a fatal memory error is logged to decide where to put a breakpoint. Compile Python with PYMEM_DEBUG_SERIALNO defined to get back the field.

.. bpo: 36588 .. date: 2019-04-11-14-36-55 .. nonce: wejLoC .. section: Core and Builtins

On AIX, :data:sys.platform doesn't contain the major version anymore. Always return 'aix', instead of 'aix3' .. 'aix7'. Since older Python versions include the version number, it is recommended to always use sys.platform.startswith('aix'). Contributed by M. Felt.

.. bpo: 36549 .. date: 2019-04-11-12-41-31 .. nonce: QSp8of .. section: Core and Builtins

Change str.capitalize to use titlecase for the first character instead of uppercase.

.. bpo: 36540 .. date: 2019-04-06-20-59-19 .. nonce: SzVUfC .. section: Core and Builtins

Implement :pep:570 (Python positional-only parameters). Patch by Pablo Galindo.

.. bpo: 36475 .. date: 2019-04-02-20-02-22 .. nonce: CjRps3 .. section: Core and Builtins

:c:func:!PyEval_AcquireLock and :c:func:!PyEval_AcquireThread now terminate the current thread if called while the interpreter is finalizing, making them consistent with :c:func:PyEval_RestoreThread, :c:func:Py_END_ALLOW_THREADS, and :c:func:PyGILState_Ensure.

.. bpo: 36504 .. date: 2019-04-02-04-10-32 .. nonce: k_V8Bm .. section: Core and Builtins

Fix signed integer overflow in _ctypes.c's PyCArrayType_new().

.. bpo: 20844 .. date: 2019-03-29-18-47-50 .. nonce: ge-7SM .. section: Core and Builtins

Fix running script with encoding cookie and LF line ending may fail on Windows.

.. bpo: 24214 .. date: 2019-03-28-15-22-45 .. nonce: tZ6lYU .. section: Core and Builtins

Fixed support of the surrogatepass error handler in the UTF-8 incremental decoder.

.. bpo: 36452 .. date: 2019-03-27-23-53-00 .. nonce: xhK2lT .. section: Core and Builtins

Changing dict keys during iteration of the dict itself, keys(), values(), or items() will now be detected in certain corner cases where keys are deleted/added so that the number of keys isn't changed. A RuntimeError will be raised after len(dict) iterations. Contributed by Thomas Perl.

.. bpo: 36459 .. date: 2019-03-27-22-35-16 .. nonce: UAvkKp .. section: Core and Builtins

Fix a possible double PyMem_FREE() due to tokenizer.c's tok_nextc().

.. bpo: 36433 .. date: 2019-03-26-17-23-02 .. nonce: -8XzZf .. section: Core and Builtins

Fixed TypeError message in classmethoddescr_call.

.. bpo: 36430 .. date: 2019-03-25-23-37-26 .. nonce: sd9xxQ .. section: Core and Builtins

Fix a possible reference leak in :func:itertools.count.

.. bpo: 36440 .. date: 2019-03-25-13-45-19 .. nonce: gkvzhi .. section: Core and Builtins

Include node names in ParserError messages, instead of numeric IDs. Patch by A. Skrobov.

.. bpo: 36143 .. date: 2019-03-20-00-37-24 .. nonce: fnKoKo .. section: Core and Builtins

Regenerate :mod:keyword from the Grammar and Tokens file using pgen. Patch by Pablo Galindo.

.. bpo: 18372 .. date: 2018-12-08-03-40-43 .. nonce: DT1nR0 .. section: Core and Builtins

Add missing :c:func:PyObject_GC_Track calls in the :mod:pickle module. Patch by Zackery Spytz.

.. bpo: 35952 .. date: 2019-04-29-11-47-06 .. nonce: 3uNuyo .. section: Library

Fix pythoninfo when the compiler is missing.

.. bpo: 28238 .. date: 2019-04-28-15-01-29 .. nonce: gdk38f .. section: Library

The .find*() methods of xml.etree.ElementTree can now search for wildcards like {*}tag and {ns}* that match a tag in any namespace or all tags in a namespace. Patch by Stefan Behnel.

.. bpo: 26978 .. date: 2019-04-28-01-52-39 .. nonce: Lpm-SI .. section: Library

pathlib.path.link_to() is now implemented. It creates a hard link pointing to a path.

.. bpo: 1613500 .. date: 2019-04-27-21-09-33 .. nonce: Ogp4P0 .. section: Library

:class:fileinput.FileInput now uses the input file mode to correctly set the output file mode (previously it was hardcoded to 'w') when inplace=True is passed to its constructor.

.. bpo: 36734 .. date: 2019-04-26-17-14-20 .. nonce: p2MaiN .. section: Library

Fix compilation of faulthandler.c on HP-UX. Initialize stack_t current_stack to zero using memset().

.. bpo: 13611 .. date: 2019-04-26-10-10-34 .. nonce: XEF4bg .. section: Library

The xml.etree.ElementTree packages gained support for C14N 2.0 serialisation. Patch by Stefan Behnel.

.. bpo: 36669 .. date: 2019-04-24-17-08-45 .. nonce: X4g0fu .. section: Library

Add missing matrix multiplication operator support to weakref.proxy.

.. bpo: 36676 .. date: 2019-04-20-13-10-34 .. nonce: XF4Egb .. section: Library

The XMLParser() in xml.etree.ElementTree provides namespace prefix context to the parser target if it defines the callback methods "start_ns()" and/or "end_ns()". Patch by Stefan Behnel.

.. bpo: 36673 .. date: 2019-04-20-09-50-32 .. nonce: XF4Egb .. section: Library

The TreeBuilder and XMLPullParser in xml.etree.ElementTree gained support for parsing comments and processing instructions. Patch by Stefan Behnel.

.. bpo: 36650 .. date: 2019-04-19-15-29-55 .. nonce: _EVdrz .. section: Library

The C version of functools.lru_cache() was treating calls with an empty **kwargs dictionary as being distinct from calls with no keywords at all. This did not result in an incorrect answer, but it did trigger an unexpected cache miss.

.. bpo: 28552 .. date: 2019-04-18-16-10-29 .. nonce: MW1TLt .. section: Library

Fix distutils.sysconfig if :data:sys.executable is None or an empty string: use :func:os.getcwd to initialize project_base. Fix also the distutils build command: don't use :data:sys.executable if it is None or an empty string.

.. bpo: 35755 .. date: 2019-04-16-17-50-39 .. nonce: Fg4EXb .. section: Library

:func:shutil.which and distutils.spawn.find_executable now use os.confstr("CS_PATH") if available instead of :data:os.defpath, if the PATH environment variable is not set. Moreover, don't use os.confstr("CS_PATH") nor :data:os.defpath if the PATH environment variable is set to an empty string.

.. bpo: 25430 .. date: 2019-04-15-12-22-09 .. nonce: 7_8kqc .. section: Library

improve performance of IPNetwork.__contains__()

.. bpo: 30485 .. date: 2019-04-13-23-42-33 .. nonce: JHhjJS .. section: Library

Path expressions in xml.etree.ElementTree can now avoid explicit namespace prefixes for tags (or the "{namespace}tag" notation) by passing a default namespace with an empty string prefix.

.. bpo: 36613 .. date: 2019-04-12-13-52-15 .. nonce: hqT1qn .. section: Library

Fix :mod:asyncio wait() not removing callback if exception

.. bpo: 36598 .. date: 2019-04-11-22-11-24 .. nonce: hfzDUl .. section: Library

Fix isinstance check for Mock objects with spec when the code is executed under tracing. Patch by Karthikeyan Singaravelan.

.. bpo: 18748 .. date: 2019-04-11-16-09-42 .. nonce: QW7upB .. section: Library

In development mode (:option:-X dev) and in debug build, the :class:io.IOBase destructor now logs close() exceptions. These exceptions are silent by default in release mode.

.. bpo: 36575 .. date: 2019-04-09-22-40-52 .. nonce: Vg_p92 .. section: Library

The _lsprof module now uses internal timer same to time.perf_counter() by default. gettimeofday(2) was used on Unix. New timer has better resolution on most Unix platforms and timings are no longer impacted by system clock updates since perf_counter() is monotonic. Patch by Inada Naoki.

.. bpo: 33461 .. date: 2019-04-09-14-46-28 .. nonce: SYJM-E .. section: Library

json.loads now emits DeprecationWarning when encoding option is specified. Patch by Matthias Bussonnier.

.. bpo: 36559 .. date: 2019-04-09-12-02-35 .. nonce: LbDRrw .. section: Library

The random module now prefers the lean internal _sha512 module over hashlib for seed(version=2) to optimize import time.

.. bpo: 17561 .. date: 2019-04-09-04-08-46 .. nonce: hOhVnh .. section: Library

Set backlog=None as the default for socket.create_server.

.. bpo: 34373 .. date: 2019-04-08-14-41-22 .. nonce: lEAl_- .. section: Library

Fix :func:time.mktime error handling on AIX for year before 1970.

.. bpo: 36232 .. date: 2019-04-06-20-25-25 .. nonce: SClmhb .. section: Library

Improve error message when trying to open existing DBM database that actually doesn't exist. Patch by Marco Rougeth.

.. bpo: 36546 .. date: 2019-04-06-14-23-00 .. nonce: YXjbyY .. section: Library

Add statistics.quantiles()

.. bpo: 36050 .. date: 2019-04-05-21-29-53 .. nonce: x9DRKE .. section: Library

Optimized http.client.HTTPResponse.read() for large response. Patch by Inada Naoki.

.. bpo: 36522 .. date: 2019-04-03-20-46-47 .. nonce: g5x3By .. section: Library

If debuglevel is set to >0 in :mod:http.client, print all values for headers with multiple values for the same header name. Patch by Matt Houglum.

.. bpo: 36492 .. date: 2019-03-31-10-21-54 .. nonce: f7vyUs .. section: Library

Deprecated passing required arguments like func as keyword arguments in functions which should accept arbitrary keyword arguments and pass them to other function. Arbitrary keyword arguments (even with names "self" and "func") can now be passed to these functions if the required arguments are passed as positional arguments.

.. bpo: 27181 .. date: 2019-03-31-01-18-52 .. nonce: LVUWcc .. section: Library

Add statistics.geometric_mean().

.. bpo: 30427 .. date: 2019-03-28-21-17-08 .. nonce: lxzvbw .. section: Library

os.path.normcase() relies on os.fspath() to check the type of its argument. Redundant checks have been removed from its posixpath.normcase() and ntpath.normcase() implementations. Patch by Wolfgang Maier.

.. bpo: 36385 .. date: 2019-03-27-02-09-22 .. nonce: we2F45 .. section: Library

Stop rejecting IPv4 octets for being ambiguously octal. Leading zeros are ignored, and no longer are assumed to specify octal octets. Octets are always decimal numbers. Octets must still be no more than three digits, including leading zeroes.

.. bpo: 36434 .. date: 2019-03-26-14-20-59 .. nonce: PTdidw .. section: Library

Errors during writing to a ZIP file no longer prevent to properly close it.

.. bpo: 36407 .. date: 2019-03-23-17-16-15 .. nonce: LG3aC4 .. section: Library

Fixed wrong indentation writing for CDATA section in xml.dom.minidom. Patch by Vladimir Surjaninov.

.. bpo: 36326 .. date: 2019-03-22-13-47-52 .. nonce: WCnEI5 .. section: Library

inspect.getdoc() can now find docstrings for member objects when slots is a dictionary.

.. bpo: 36366 .. date: 2019-03-20-15-13-18 .. nonce: n0eav_ .. section: Library

Calling stop() on an unstarted or stopped :func:unittest.mock.patch object will now return None instead of raising :exc:RuntimeError, making the method idempotent. Patch by Karthikeyan Singaravelan.

.. bpo: 36348 .. date: 2019-03-18-16-16-55 .. nonce: E0w_US .. section: Library

The :meth:imap.IMAP4.logout method no longer ignores silently arbitrary exceptions.

.. bpo: 31904 .. date: 2019-03-13-16-48-42 .. nonce: 9sjd38 .. section: Library

Add time module support and fix test_time failures for VxWorks.

.. bpo: 36227 .. date: 2019-03-07-20-02-18 .. nonce: i2Z1XR .. section: Library

Added support for keyword arguments default_namespace and xml_declaration in functions ElementTree.tostring() and ElementTree.tostringlist().

.. bpo: 36004 .. date: 2019-02-17-12-55-51 .. nonce: hCt_KK .. section: Library

Added new alternate constructors :meth:datetime.date.fromisocalendar and :meth:datetime.datetime.fromisocalendar, which construct date objects from ISO year, week number and weekday; these are the inverse of each class's isocalendar method. Patch by Paul Ganssle.

.. bpo: 35936 .. date: 2019-02-16-22-19-32 .. nonce: Ay5WtD .. section: Library

:mod:modulefinder no longer depends on the deprecated :mod:imp module, and the initializer for :class:modulefinder.ModuleFinder now has immutable default arguments. Patch by Brandt Bucher.

.. bpo: 35376 .. date: 2019-02-13-18-56-27 .. nonce: UFhYLj .. section: Library

:mod:modulefinder correctly handles modules that have the same name as a bad package. Patch by Brandt Bucher.

.. bpo: 17396 .. date: 2019-02-13-18-56-22 .. nonce: oKRkrD .. section: Library

:mod:modulefinder no longer crashes when encountering syntax errors in followed imports. Patch by Brandt Bucher.

.. bpo: 35934 .. date: 2019-02-07-20-25-39 .. nonce: QmfNmY .. section: Library

Added :meth:~socket.create_server and :meth:~socket.has_dualstack_ipv6 convenience functions to automate the necessary tasks usually involved when creating a server socket, including accepting both IPv4 and IPv6 connections on the same socket. (Contributed by Giampaolo Rodola in :issue:17561.)

.. bpo: 23078 .. date: 2019-01-18-23-10-10 .. nonce: l4dFoj .. section: Library

Add support for :func:classmethod and :func:staticmethod to :func:unittest.mock.create_autospec. Initial patch by Felipe Ochoa.

.. bpo: 35416 .. date: 2018-12-05-09-55-05 .. nonce: XALKZG .. section: Library

Fix potential resource warnings in distutils. Patch by Mickaël Schoentgen.

.. bpo: 25451 .. date: 2018-11-07-23-44-25 .. nonce: re_8db .. section: Library

Add transparency methods to :class:tkinter.PhotoImage. Patch by Zackery Spytz.

.. bpo: 35082 .. date: 2018-10-27-11-54-12 .. nonce: HDj1nr .. section: Library

Don't return deleted attributes when calling dir on a :class:unittest.mock.Mock.

.. bpo: 34547 .. date: 2018-10-05-16-01-00 .. nonce: abbaa .. section: Library

:class:wsgiref.handlers.BaseHandler now handles abrupt client connection terminations gracefully. Patch by Petter Strandmark.

.. bpo: 31658 .. date: 2018-07-30-12-00-15 .. nonce: bx7a .. section: Library

:func:xml.sax.parse now supports :term:path-like <path-like object>. Patch by Mickaël Schoentgen.

.. bpo: 34139 .. date: 2018-07-18-11-25-34 .. nonce: tKbmW7 .. section: Library

Remove stale unix datagram socket before binding

.. bpo: 33530 .. date: 2018-05-29-18-34-53 .. nonce: _4Q_bi .. section: Library

Implemented Happy Eyeballs in asyncio.create_connection(). Added two new arguments, happy_eyeballs_delay and interleave, to specify Happy Eyeballs behavior.

.. bpo: 33291 .. date: 2018-04-11-11-41-52 .. nonce: -xLGf8 .. section: Library

Do not raise AttributeError when calling the inspect functions isgeneratorfunction, iscoroutinefunction, isasyncgenfunction on a method created from an arbitrary callable. Instead, return False.

.. bpo: 31310 .. date: 2018-04-06-11-06-23 .. nonce: eq9ky0 .. section: Library

Fix the multiprocessing.semaphore_tracker so it is reused by child processes

.. bpo: 31292 .. date: 2017-08-30-20-27-00 .. nonce: dKIaZb .. section: Library

Fix setup.py check --restructuredtext for files containing include directives.

.. bpo: 36625 .. date: 2019-04-15-12-02-45 .. nonce: x3LMCF .. section: Documentation

Remove obsolete comments from docstrings in fractions.Fraction

.. bpo: 30840 .. date: 2019-04-14-19-46-21 .. nonce: R-JFzw .. section: Documentation

Document relative imports

.. bpo: 36523 .. date: 2019-04-04-19-11-47 .. nonce: sG1Tr4 .. section: Documentation

Add docstring for io.IOBase.writelines().

.. bpo: 36425 .. date: 2019-03-27-22-46-00 .. nonce: kG9gx1 .. section: Documentation

New documentation translation: Simplified Chinese <https://docs.python.org/zh-cn/>_.

.. bpo: 36345 .. date: 2019-03-26-14-58-34 .. nonce: r2stx3 .. section: Documentation

Avoid the duplication of code from Tools/scripts/serve.py in using the :rst:dir:literalinclude directive for the basic wsgiref-based web server in the documentation of :mod:wsgiref. Contributed by Stéphane Wirtel.

.. bpo: 36345 .. date: 2019-03-23-09-25-12 .. nonce: L704Zv .. section: Documentation

Using the code of the Tools/scripts/serve.py script as an example in the :mod:wsgiref documentation. Contributed by Stéphane Wirtel.

.. bpo: 36157 .. date: 2019-03-08-15-39-47 .. nonce: nF1pP1 .. section: Documentation

Added documentation for PyInterpreterState_Main().

.. bpo: 33043 .. date: 2019-02-24-03-15-10 .. nonce: 8knWTS .. section: Documentation

Updates the docs.python.org page with the addition of a 'Contributing to Docs' link at the end of the page (between 'Reporting Bugs' and 'About Documentation'). Updates the 'Found a Bug' page with additional links and information in the Documentation Bugs section.

.. bpo: 35581 .. date: 2018-12-25-12-56-57 .. nonce: aA7r6T .. section: Documentation

@typing.type_check_only now allows type stubs to mark functions and classes not available during runtime.

.. bpo: 33832 .. date: 2018-06-15-15-57-37 .. nonce: xBFhKw .. section: Documentation

Add glossary entry for 'magic method'.

.. bpo: 32913 .. date: 2018-02-22-15-48-16 .. nonce: f3utho .. section: Documentation

Added re.Match.groupdict example to regex HOWTO.

.. bpo: 36719 .. date: 2019-04-26-09-02-49 .. nonce: ys2uqH .. section: Tests

regrtest now always detects uncollectable objects. Previously, the check was only enabled by --findleaks. The check now also works with -jN/--multiprocess N. --findleaks becomes a deprecated alias to --fail-env-changed.

.. bpo: 36725 .. date: 2019-04-26-04-12-29 .. nonce: B8-ghi .. section: Tests

When using multiprocessing mode (-jN), regrtest now better reports errors if a worker process fails, and it exits immediately on a worker thread failure or when interrupted.

.. bpo: 36454 .. date: 2019-04-23-17-48-11 .. nonce: 0q4lQz .. section: Tests

Change test_time.test_monotonic() to test only the lower bound of elapsed time after a sleep command rather than the upper bound. This prevents unnecessary test failures on slow buildbots. Patch by Victor Stinner.

.. bpo: 32424 .. date: 2019-04-21-17-55-18 .. nonce: yDy49h .. section: Tests

Improve test coverage for xml.etree.ElementTree. Patch by Gordon P. Hemsley.

.. bpo: 32424 .. date: 2019-04-21-17-53-50 .. nonce: Q4rBmn .. section: Tests

Fix typo in test_cyclic_gc() test for xml.etree.ElementTree. Patch by Gordon P. Hemsley.

.. bpo: 36635 .. date: 2019-04-15-16-55-49 .. nonce: __FTq9 .. section: Tests

Add a new :mod:!_testinternalcapi module to test the internal C API.

.. bpo: 36629 .. date: 2019-04-15-11-57-39 .. nonce: ySnaL3 .. section: Tests

Fix test_imap4_host_default_value() of test_imaplib: catch also :const:errno.ENETUNREACH error.

.. bpo: 36611 .. date: 2019-04-12-12-44-42 .. nonce: UtorXL .. section: Tests

Fix test_sys.test_getallocatedblocks() when :mod:tracemalloc is enabled.

.. bpo: 36560 .. date: 2019-04-09-14-08-02 .. nonce: _ejeOr .. section: Tests

Fix reference leak hunting in regrtest: compute also deltas (of reference count, allocated memory blocks, file descriptor count) during warmup, to ensure that everything is initialized before starting to hunt reference leaks.

.. bpo: 36565 .. date: 2019-04-08-19-01-21 .. nonce: 2bxgtU .. section: Tests

Fix reference hunting (python3 -m test -R 3:3) when Python has no built-in abc module.

.. bpo: 31904 .. date: 2019-04-08-09-24-36 .. nonce: ab03ea .. section: Tests

Port test_resource to VxWorks: skip tests cases setting RLIMIT_FSIZE and RLIMIT_CPU.

.. bpo: 31904 .. date: 2019-04-01-16-06-36 .. nonce: peaceF .. section: Tests

Fix test_tabnanny on VxWorks: adjust ENOENT error message.

.. bpo: 36436 .. date: 2019-03-26-13-49-21 .. nonce: yAtN0V .. section: Tests

Fix _testcapi.pymem_buffer_overflow(): handle memory allocation failure.

.. bpo: 31904 .. date: 2019-03-19-17-39-25 .. nonce: QxhhRx .. section: Tests

Fix test_utf8_mode on VxWorks: Python always use UTF-8 on VxWorks.

.. bpo: 36341 .. date: 2019-03-18-10-47-45 .. nonce: UXlY0P .. section: Tests

Fix tests that may fail with PermissionError upon calling bind() on AF_UNIX sockets.

.. bpo: 36747 .. date: 2019-04-29-09-57-20 .. nonce: 1YEyu- .. section: Build

Remove the stale scriptsinstall Makefile target.

.. bpo: 21536 .. date: 2019-04-25-01-51-52 .. nonce: ACQkiC .. section: Build

On Unix, C extensions are no longer linked to libpython except on Android and Cygwin.

It is now possible for a statically linked Python to load a C extension built using a shared library Python.

When Python is embedded, libpython must not be loaded with RTLD_LOCAL, but RTLD_GLOBAL instead. Previously, using RTLD_LOCAL, it was already not possible to load C extensions which were not linked to libpython, such as C extensions of the standard library built by the *shared* section of Modules/Setup.

distutils, python-config and python-config.py have been modified.

.. bpo: 36707 .. date: 2019-04-24-02-29-15 .. nonce: 8ZNB67 .. section: Build

./configure --with-pymalloc no longer adds the m flag to SOABI (sys.implementation.cache_tag). Enabling or disabling pymalloc has no impact on the ABI.

.. bpo: 36635 .. date: 2019-04-16-13-58-52 .. nonce: JKlzkf .. section: Build

Change PyAPI_FUNC(type), PyAPI_DATA(type) and PyMODINIT_FUNC macros of pyport.h when Py_BUILD_CORE_MODULE is defined. The Py_BUILD_CORE_MODULE define must be now be used to build a C extension as a dynamic library accessing Python internals: export the :samp:PyInit_{xxx}() function in DLL exports on Windows.

.. bpo: 31904 .. date: 2019-04-15-15-01-29 .. nonce: 38fdkg .. section: Build

Don't build the _crypt extension on VxWorks.

.. bpo: 36618 .. date: 2019-04-12-19-49-10 .. nonce: gcI9iq .. section: Build

Add -fmax-type-align=8 to CFLAGS when clang compiler is detected. The pymalloc memory allocator aligns memory on 8 bytes. On x86-64, clang expects alignment on 16 bytes by default and so uses MOVAPS instruction which can lead to segmentation fault. Instruct clang that Python is limited to alignment on 8 bytes to use MOVUPS instruction instead: slower but don't trigger a SIGSEGV if the memory is not aligned on 16 bytes. Sadly, the flag must be added to CFLAGS and not just CFLAGS_NODIST, since third party C extensions can have the same issue.

.. bpo: 36605 .. date: 2019-04-11-18-50-58 .. nonce: gk5czf .. section: Build

make tags and make TAGS now also parse Modules/_io/*.c and Modules/_io/*.h.

.. bpo: 36465 .. date: 2019-04-09-18-19-43 .. nonce: -w6vx6 .. section: Build

Release builds and debug builds are now ABI compatible: defining the Py_DEBUG macro no longer implies the Py_TRACE_REFS macro, which introduces the only ABI incompatibility. The Py_TRACE_REFS macro, which adds the :func:sys.getobjects function and the :envvar:PYTHONDUMPREFS environment variable, can be set using the new ./configure --with-trace-refs build option.

.. bpo: 36577 .. date: 2019-04-09-17-31-47 .. nonce: 34kuUW .. section: Build

setup.py now correctly reports missing OpenSSL headers and libraries again.

.. bpo: 36544 .. date: 2019-04-06-18-53-03 .. nonce: hJr2_a .. section: Build

Fix regression introduced in bpo-36146 refactoring setup.py

.. bpo: 36508 .. date: 2019-04-02-17-01-23 .. nonce: SN5Y6N .. section: Build

python-config --ldflags no longer includes flags of the LINKFORSHARED variable. The LINKFORSHARED variable must only be used to build executables.

.. bpo: 36503 .. date: 2019-04-02-09-25-23 .. nonce: 0xzfkQ .. section: Build

Remove references to "aix3" and "aix4". Patch by M. Felt.

.. bpo: 35920 .. date: 2019-04-22-16-59-20 .. nonce: VSfGOI .. section: Windows

Added platform.win32_edition() and platform.win32_is_iot(). Added support for cross-compiling packages for Windows ARM32. Skip tests that are not expected to work on Windows IoT Core ARM32.

.. bpo: 36649 .. date: 2019-04-17-11-39-24 .. nonce: arbzIo .. section: Windows

Remove trailing spaces for registry keys when installed via the Store.

.. bpo: 34144 .. date: 2019-04-10-04-35-31 .. nonce: _KzB5z .. section: Windows

Fixed activate.bat to correctly update codepage when chcp.com returns dots in output. Patch by Lorenz Mende.

.. bpo: 36509 .. date: 2019-04-02-10-11-18 .. nonce: DdaM67 .. section: Windows

Added preset-iot layout for Windows IoT ARM containers. This layout doesn't contain UI components like tkinter or IDLE. It also doesn't contain files to support on-target builds since Windows ARM32 builds must be cross-compiled when using MSVC.

.. bpo: 35941 .. date: 2019-03-28-03-51-16 .. nonce: UnlAEE .. section: Windows

enum_certificates function of the ssl module now returns certificates from all available certificate stores inside windows in a query instead of returning only certificates from the system wide certificate store. This includes certificates from these certificate stores: local machine, local machine enterprise, local machine group policy, current user, current user group policy, services, users. ssl.enum_crls() function is changed in the same way to return all certificate revocation lists inside the windows certificate revocation list stores.

.. bpo: 36441 .. date: 2019-03-26-11-46-15 .. nonce: lYjGF1 .. section: Windows

Fixes creating a venv when debug binaries are installed.

.. bpo: 36085 .. date: 2019-03-18-11-44-49 .. nonce: mLfxfc .. section: Windows

Enable better DLL resolution on Windows by using safe DLL search paths and adding :func:os.add_dll_directory.

.. bpo: 36010 .. date: 2019-03-16-10-24-58 .. nonce: dttWfp .. section: Windows

Add the venv standard library module to the nuget distribution for Windows.

.. bpo: 29515 .. date: 2019-03-05-18-09-43 .. nonce: vwUTv0 .. section: Windows

Add the following socket module constants on Windows: IPPROTO_AH IPPROTO_CBT IPPROTO_DSTOPTS IPPROTO_EGP IPPROTO_ESP IPPROTO_FRAGMENT IPPROTO_GGP IPPROTO_HOPOPTS IPPROTO_ICLFXBM IPPROTO_ICMPV6 IPPROTO_IDP IPPROTO_IGMP IPPROTO_IGP IPPROTO_IPV4 IPPROTO_IPV6 IPPROTO_L2TP IPPROTO_MAX IPPROTO_ND IPPROTO_NONE IPPROTO_PGM IPPROTO_PIM IPPROTO_PUP IPPROTO_RDP IPPROTO_ROUTING IPPROTO_SCTP IPPROTO_ST

.. bpo: 35947 .. date: 2019-02-11-14-53-17 .. nonce: 9vI4hP .. section: Windows

Added current version of libffi to cpython-source-deps. Change _ctypes to use current version of libffi on Windows.

.. bpo: 34060 .. date: 2018-07-20-13-09-19 .. nonce: v-z87j .. section: Windows

Report system load when running test suite on Windows. Patch by Ammar Askar. Based on prior work by Jeremy Kloth.

.. bpo: 31512 .. date: 2017-10-04-12-40-45 .. nonce: YQeBt2 .. section: Windows

With the Windows 10 Creators Update, non-elevated users can now create symlinks as long as the computer has Developer Mode enabled.

.. bpo: 34602 .. date: 2019-04-29-10-54-14 .. nonce: Lrl2zU .. section: macOS

Avoid failures setting macOS stack resource limit with resource.setrlimit. This reverts an earlier fix for bpo-18075 which forced a non-default stack size when building the interpreter executable on macOS.

.. bpo: 36429 .. date: 2019-03-26-00-09-50 .. nonce: w-jL2e .. section: IDLE

Fix starting IDLE with pyshell. Add idlelib.pyshell alias at top; remove pyshell alias at bottom. Remove obsolete name=='main' command.

.. bpo: 14546 .. date: 2019-04-30-14-30-29 .. nonce: r38Y-6 .. section: Tools/Demos

Fix the argument handling in Tools/scripts/lll.py.

.. bpo: 36763 .. date: 2019-05-01-00-42-08 .. nonce: vghb86 .. section: C API

Fix memory leak in :c:func:!Py_SetStandardStreamEncoding: release memory if the function is called twice.

.. bpo: 36641 .. date: 2019-04-16-21-18-19 .. nonce: pz-DIR .. section: C API

:c:expr:PyDoc_VAR(name) and :c:expr:PyDoc_STRVAR(name,str) now create static const char name[] instead of static char name[]. Patch by Inada Naoki.

.. bpo: 36389 .. date: 2019-04-11-12-20-35 .. nonce: P9QFoP .. section: C API

Change the value of CLEANBYTE, DEADDYTE and FORBIDDENBYTE internal constants used by debug hooks on Python memory allocators (:c:func:PyMem_SetupDebugHooks function). Byte patterns 0xCB, 0xDB and 0xFB have been replaced with 0xCD, 0xDD and 0xFD to use the same values than Windows CRT debug malloc() and free().

.. bpo: 36443 .. date: 2019-03-27-15-58-23 .. nonce: tAfZR9 .. section: C API

Since Python 3.7.0, calling :c:func:Py_DecodeLocale before :c:func:Py_Initialize produces mojibake if the LC_CTYPE locale is coerced and/or if the UTF-8 Mode is enabled by the user configuration. The LC_CTYPE coercion and UTF-8 Mode are now disabled by default to fix the mojibake issue. They must now be enabled explicitly (opt-in) using the new :c:func:!_Py_PreInitialize API with _PyPreConfig.

.. bpo: 36025 .. date: 2019-02-19-08-23-42 .. nonce: tnwylQ .. section: C API

Fixed an accidental change to the datetime C API where the arguments to the :c:func:PyDate_FromTimestamp function were incorrectly interpreted as a single timestamp rather than an arguments tuple, which causes existing code to start raising :exc:TypeError. The backwards-incompatible change was only present in alpha releases of Python 3.8. Patch by Paul Ganssle.

.. bpo: 35810 .. date: 2019-01-23-12-38-11 .. nonce: wpbWeb .. section: C API

Modify PyObject_Init to correctly increase the refcount of heap-allocated Type objects. Also fix the refcounts of the heap-allocated types that were either doing this manually or not decreasing the type's refcount in tp_dealloc