* Add the c_init_default attribute which is used to initialize the C variable
if the default is not explicitly provided.
* Add the c_default_init() method which is used to derive c_default from
default if c_default is not explicitly provided.
* Explicit c_default and py_default are now almost always have precedence
over the generated value.
* Add support for bytes literals as default values.
* Improve support for str literals as default values (support non-ASCII
and non-printable characters and special characters like backslash or quotes).
* Fix support for str and bytes literals containing trigraphs, "/*" and "*/".
* Improve support for default values in converters "char" and "int(accept={str})".
* Converter "int(accept={str})" now requires 1-character string instead of
integer as default value.
* Add support for non-None default values in converter "Py_buffer": NULL,
str and bytes literals.
* Improve error handling for invalid default values.
* Rename Null to NullType for consistency.
(cherry picked from commit 99e2c5eccd)
Docs: a brief note in the sets tutorial about order (GH-145984)
(cherry picked from commit 4f5e79805e)
Docs: a brief note in the sets tut about order
Co-authored-by: Ned Batchelder <ned@nedbatchelder.com>
The test doesn't actually test any pyrepl code (it runs Python with -S)
and has a race condition that causes intermittent timeouts on CI.
(cherry picked from commit e18abc6a1f)
Co-authored-by: Sam Gross <colesbury@gmail.com>
gh-145599, CVE 2026-3644: Reject control characters in `http.cookies.Morsel.update()` (GH-145600)
Reject control characters in `http.cookies.Morsel.update()` and `http.cookies.BaseCookie.js_output`.
(cherry picked from commit 57e88c1cf9)
Co-authored-by: Stan Ulbrych <89152624+StanFromIreland@users.noreply.github.com>
Co-authored-by: Victor Stinner <vstinner@python.org>
Co-authored-by: Victor Stinner <victor.stinner@gmail.com>
gh-145649: Fix man page text wrapping for -X option (GH-145656)
Replace hardcoded space indentation with proper troff macros
(.TP, .RS/.RE, .IP) for -X sub-options so text wraps correctly
at any terminal width.
(cherry picked from commit 36b5284f04)
Co-authored-by: Matt Van Horn <mvanhorn@users.noreply.github.com>
Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>
Docs: fix a form error and a grammatical error in float.rst (GH-140989)
(cherry picked from commit 70397fd103)
Co-authored-by: RayXu <xu_ruihong2009@163.com>
gh-140814: Fix freeze_support() setting start method as side effect (GH-144608)
freeze_support() called get_start_method() without allow_none=True,
which locked in the default start method context. This caused a
subsequent set_start_method() call to raise "context has already been
set". Use allow_none=True and accept None as a matching value, since
spawn.freeze_support() independently detects spawned child processes.
Test that freeze_support() does not lock in the default start method,
which would prevent a subsequent set_start_method() call.
(cherry picked from commit ee5318025b)
Co-authored-by: Gregory P. Smith <68491+gpshead@users.noreply.github.com>
Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>
Co-authored-by: Bénédikt Tran <10796600+picnixz@users.noreply.github.com>
gh-145986: Avoid unbound C recursion in `conv_content_model` in `pyexpat.c` (CVE 2026-4224) (GH-145987)
Fix C stack overflow (CVE-2026-4224) when an Expat parser
with a registered `ElementDeclHandler` parses inline DTD
containing deeply nested content model.
---------
(cherry picked from commit eb0e8be3a7)
Co-authored-by: Stan Ulbrych <89152624+StanFromIreland@users.noreply.github.com>
Co-authored-by: Bénédikt Tran <10796600+picnixz@users.noreply.github.com>
Docs: except with multiple exceptions parentheses not required (GH-145848)
As of PEP 758 the except statement doesn't require parentheses anymore for exception tuples.
(cherry picked from commit 6d1e9ceed3)
See: https://peps.python.org/pep-0758/
Co-authored-by: Maurizio Sambati <duilio@users.noreply.github.com>
gh-145801: Use gcc -fprofile-update=atomic for PGO builds (GH-145802)
When Python build is optimized with GCC using PGO, use
-fprofile-update=atomic option to use atomic operations when updating
profile information. This option reduces the risk of gcov Data Files
(.gcda) corruption which can cause random GCC crashes.
(cherry picked from commit 08a018ebe0)
Co-authored-by: Victor Stinner <vstinner@python.org>
Avoid locking in the PyType_Lookup cache-miss path if the type's
tp_version_tag is already valid.
(cherry picked from commit cd52172831)
Co-authored-by: Sam Gross <colesbury@gmail.com>
gh-140594: Fix an out of bounds read when feeding NUL byte to PyOS_StdioReadline() (GH-140910)
(cherry picked from commit 86a0756234)
Co-authored-by: Shamil <ashm.tech@proton.me>
Co-authored-by: Bénédikt Tran <10796600+picnixz@users.noreply.github.com>
Co-authored-by: Victor Stinner <vstinner@python.org>
(cherry picked from commit 2d35f9bc1c)
Includes test fix-up from GH-145788
(cherry picked from commit aa4240ebea)
Co-authored-by: Thomas Kowalski <thom.kowa@gmail.com>
Co-authored-by: Matt Van Horn <mvanhorn@users.noreply.github.com>
(cherry picked from commit eb9ae65e5b)
Co-authored-by: Stan Ulbrych <89152624+StanFromIreland@users.noreply.github.com>
Co-authored-by: Ned Batchelder <ned@nedbatchelder.com>
gh-145607: Ensure BIG_DATA has two compressed blocks in test_bz2 (GH-145730)
(cherry picked from commit 19676e5fc2)
Co-authored-by: Emma Smith <emma@emmatyping.dev>
Modifies the Emscripten build script to allow for caching of dependencies, and
for automated installation of new EMSDK versions.
(cherry picked from commit ebb150e76a)
Co-authored-by: Hood Chatham <roberthoodchatham@gmail.com>
Co-authored-by: Russell Keith-Magee <russell@keith-magee.com>
The cache may be cleared between the evaluation of the if statement and the
call to popitem.
(cherry picked from commit 665c1db94f)
Co-authored-by: Sam Gross <colesbury@gmail.com>
