cpython/Misc/NEWS.d/3.8.0a4.rst

.. 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, :attr:`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 faiures 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 Documention 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
:data:`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 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:macro:`PyDoc_VAR(name)` and :c:macro:`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