Petr Viktorin [Thu, 15 Jan 2026 11:37:30 +0000 (12:37 +0100)]
gh-141004: Mark up docs of old PyMem macros (GH-143783)
These had a docs-only deprecation notice since the first version of the docs in this repo. Nowadays we call things “soft deprecated” if there's just a note in the docs.
The deprecated directive needs a version, I went with the first one that had the notice (2.0; it's not in 1.6):
- https://docs.python.org/release/2.0/api/memoryInterface.html
- https://docs.python.org/release/1.6/api/memoryInterface.html
Since PEP 445, they are now direct aliases; there are no (additional) binary compatibility concerns over the preferred names.
Peter Gessler [Thu, 15 Jan 2026 09:51:11 +0000 (03:51 -0600)]
gh-80620: Support negative timestamps on windows in `time.gmtime`, `time.localtime`, and `datetime` module (#143463)
Previously, negative timestamps (representing dates before 1970-01-01) were
not supported on Windows due to platform limitations. The changes introduce a
fallback implementation using the Windows FILETIME API, allowing negative
timestamps to be correctly handled in both UTC and local time conversions.
Additionally, related test code is updated to remove Windows-specific skips
and error handling, ensuring consistent behavior across platforms.
Co-authored-by: Victor Stinner <vstinner@python.org>
Add the unicodedata.iter_graphemes() function to iterate over grapheme
clusters according to rules defined in Unicode Standard Annex #29.
Add unicodedata.grapheme_cluster_break(), unicodedata.indic_conjunct_break()
and unicodedata.extended_pictographic() functions to get the properties
of the character which are related to the above algorithm.
Duane Griffin [Wed, 14 Jan 2026 11:25:46 +0000 (00:25 +1300)]
gh-106287: Do not write objects after an unmarshalling error (GH-132715)
Writing out an object may involve a slot lookup, which is not safe to do with
an exception raised. In debug mode an assertion failure will occur if this
happens.
Petr Viktorin [Wed, 14 Jan 2026 09:54:45 +0000 (10:54 +0100)]
gh-141004: Document old provisional names for vectorcall/code API (GH-143568)
gh-141004: Document old provisional names for vectorcall & code API
For vectorcall API, the underscore-prefixed provisional names
continue to be available per PEP 590:
https://peps.python.org/pep-0590/#finalizing-the-api
Use `versionadded`, `versionchanged`, and `:no-typesetting:`
to mark this up.
For PyCode API, use `:no-typesetting:` rather than `index::` so that
these are semantically documented as C functions.
Petr Viktorin [Tue, 13 Jan 2026 12:21:59 +0000 (13:21 +0100)]
gh-143054: Disallow non-top-level Cut for now (GH-143622)
The behaviour of Cut in nested parentheses, Repeat, Opt, and similar
is somewhat chaotic. Apparently even the academic papers on PEG aren't
as clear as they could be.
And it doesn't really matter. Python only uses top-level cuts.
When that changes, we can clarify as much as necessary (and even
change the implementation to make sense for what we'll need).
Document that this is deliberately unspecified, and add a test to
make sure any decision is deliberate, tested and documented.
Gregory P. Smith [Mon, 12 Jan 2026 23:47:21 +0000 (15:47 -0800)]
gh-143706: Fix sys.argv not set during multiprocessing forkserver `__main__` preload (#143717)
The forkserver was not passing sys.argv to its main() function, causing
sys.argv to be empty during `__main__` module import in child processes. This
fixes a non-obvious regression inadvertently introduced by the gh-126631 main
preloading fix.
Łukasz Langa [Mon, 12 Jan 2026 23:01:01 +0000 (00:01 +0100)]
Bump automatic certificate update on Windows during builds (GH-143741)
Without this, OpenSSL that we use to download external dependencies might use a stale certificate store and be unable to connect to servers. We need to use a Windows-specific HTTP client that uses CryptoAPI directly to trigger certificate updates.
We only do it on failure to avoid hitting servers twice. And we only do it once per each URL.
Serhiy Storchaka [Mon, 12 Jan 2026 18:23:05 +0000 (20:23 +0200)]
gh-143196: Fix crash in non-standard use of internal JSON encoder object (GH-143618)
The internal encoder object returned by undocumented function
json.encoder.c_make_encoder() (aka _json.make_encoder()) crashed
when it was called with non-zero second argument.
Terry Jan Reedy [Mon, 12 Jan 2026 17:55:06 +0000 (12:55 -0500)]
gh-139707: Copy-strip change to idle.rst into idlelib (#143718)
On Windows, running `python -c "from idlelib.help import copy_strip;
copy_strip()"` after idle.html is built results in
`f:\dev\3x\Doc\build\html\library\idle.html
copied to f:\dev\3x\Lib\idlelib\help.html`
This PR commits the html change to idlelib/help.html.
gh-137113 docs: note readline no longer supported in REPL after 3.13 (GH-137142)
Add a note to the readline module documentation stating that
Python 3.13 and later no longer supports readline in the default REPL,
as per gh-118840. Includes workaround using PYTHON_BASIC_REPL.
Update tutorial to remove the reference, and use a different key to
test things out.
gh-143006: Fix and optimize mixed comparison of float and int (GH-143084)
When comparing negative non-integer float and int with the same number
of bits in the integer part, __neg__() in the int subclass returning
not an int caused an assertion error.
Now the integer is no longer negated. Also, reduced the number of
temporary created Python objects.
gh-143460: Skip infinite recusion tests for infinite stack size (#143606)
Avoid tests being killed due to OOM on Linux if a system is configured with
'ulimit -s unlimited' by skipping tests relying on infinite recursion.
While unclear if Python should support 'ulimit -s unlimited', we should at
least try to avoid failing a PGO build running tests due to an unlimited
stack size being set.
Signed-off-by: Jan André Reuter <j.reuter@fz-juelich.de>
zhong [Fri, 9 Jan 2026 11:50:56 +0000 (03:50 -0800)]
gh-143378: Fix use-after-free when BytesIO is concurrently mutated during write operations (GH-143408)
PyObject_GetBuffer() can execute user code (e.g. via __buffer__), which may
close or otherwise mutate a BytesIO object while write() or writelines()
is in progress. This could invalidate the internal buffer and lead to a
use-after-free.
Ensure that PyObject_GetBuffer() is called before validation checks.