[3.13] gh-117655: Prevent `test_strptime` from raising a DeprecationWarning (GH-117668) (GH-118956)
gh-117655: Prevent `test_strptime` from raising a DeprecationWarning (GH-117668)
* Fix `test_strptime` raises a DeprecationWarning
* Ignore deprecation warnings where appropriate.
* Update Lib/test/datetimetester.py
This is follow on work to silence unnecessary warnings from the test suite that changes for https://github.com/python/cpython/issues/70647 added.
(cherry picked from commit abead548af0172dabba13da8bacf2da3c02d4927)
[3.13] gh-117657: Log TSAN warnings to separate files and archive them (GH-118747) (#118931)
This ensures we don't lose races that occur in subprocesses or
interleave races from workers running in parallel.
Log files are collected and packaged into a zipfile that can be
downloaded from the "Artifacts" section of the workflow run.
(cherry picked from commit b88889e9ffd7b2d2bdac75aecbf14e37fd68e337)
[3.13] gh-118846: Fix free-threading test failures when run sequentially (GH-118864) (#118927)
The free-threaded build currently immortalizes some objects once the
first thread is started. This can lead to test failures depending on the
order in which tests are run. This PR addresses those failures by
suppressing immortalization or skipping the affected tests.
(cherry picked from commit b309c8ebff011f27012367b046ff92eecbdd68a5)
`_Py_qsbr_unregister` is called when the PyThreadState is already
detached, so the access to `tstate->qsbr` isn't safe without locking the
shared mutex. Grab the `struct _qsbr_shared` from the interpreter
instead.
(cherry picked from commit 33d20199af65c741bdc908a968edd8dc179b6974)
_PyWeakref_ClearRef was previously exposed in the public C-API, although
it begins with an underscore and is not documented. It's used by a few
C-API extensions. There is currently no alternative public API that can
replace its use.
_PyWeakref_ClearWeakRefsExceptCallbacks is the only thread-safe way to
use _PyWeakref_ClearRef in the free-threaded build. This exposes the C
symbol, but does not make the API public.
(cherry picked from commit db5af7da092409030c9fbe0a3a986bd0ee441b8b)
[3.13] gh-117657: Replace TSAN suppresions with more specific rules (GH-118722) (#118870)
Using `race:` filters out warnings if the function appears anywhere in
the stack trace. This can hide a lot of unrelated warnings, especially
for a function like `_PyEval_EvalFrameDefault`, which is somewhere on
the stack more often than not.
Change all free-threaded suppressions to `race_top:`, which only matches
the top frame, and add any new suppressions this exposes.
(cherry picked from commit 98ff3f65c0232f31df89ebb52b244625ec9e3eb6)
[3.13] gh-116984: Make mimalloc header includes relative to the current file (GH-118808) (#118866)
Some embedders and extensions include parts of the internal API. The
pycore_mimalloc.h file is transitively include by a number of other
internal headers. This avoids include errors for code that was
already including those headers.
(cherry picked from commit 71cc0651e79041abd648595f3030dfa41009137a)
The `list_preallocate_exact` function did not zero initialize array
contents. In the free-threaded build, this could expose uninitialized
memory to concurrent readers between the call to
`list_preallocate_exact` and the filling of the array contents with
items.
(cherry picked from commit 2402715e10d00ef60fad2948d8461559d084eb36)
[3.13] gh-117657: Acquire a critical section around `SemLock.__{enter,exit}__` (GH-118812) (#118856)
These methods are purely wrappers around `Semlock.{acquire,release}`,
which expect a critical section to be held.
(cherry picked from commit c30d8e5d6c6b657817d6b342f1021676d04dd5af)
[3.13] gh-117657: Fix data races when writing / reading `ob_gc_bits` (GH-118292) (#118796)
Use relaxed atomics when reading / writing to the field. There are still a
few places in the GC where we do not use atomics. Those should be safe as
the world is stopped.
(cherry picked from commit cb6f75a32ca2649c6cc1cabb0301eb783efbd55b)
Tim Peters [Wed, 8 May 2024 00:09:09 +0000 (19:09 -0500)]
gh-118610: Centralize power caching in `_pylong.py` (#118611)
A new `compute_powers()` function computes all and only the powers of the base the various base-conversion functions need, as efficiently as reasonably possible (turns out that invoking `**`is needed at most once). This typically gives a few % speedup, but the primary point is to simplify the base-conversion functions, which no longer need their own, ad hoc, and less efficient power-caching schemes.
T. Wouters [Tue, 7 May 2024 21:00:25 +0000 (23:00 +0200)]
gh-109975: Make a rough editorial pass over What's New (#118711)
Make a rough editorial pass over Python 3.13's What's New document. Add the
release highlights, remove or merge some duplicated entries, and reorder
some of the sections (removals should really go before future deprecations).
The `pool_in_threads.py` test file may crash in free-threaded builds,
which can lead to the Tsan test hanging. Skip it for now until we fix
the underlying issue.
gh-66410: Do not stringify arguments of Tkinter callback (GH-98592)
Callbacks registered in the tkinter module now take arguments as
various Python objects (int, float, bytes, tuple), not just str.
To restore the previous behavior set tkinter module global wantobject to 1
before creating the Tk object or call the wantobject() method of the Tk object
with argument 1.
Calling it with argument 2 restores the current default behavior.
gh-118310: Fix documentation for `enum.Enum.__new__` (GH-118311)
The provided example was incorrect:
- The example enum was missing the `int` mixin as implied by the context
- The value of `int('1a', 16)` was incorrectly given as 17
(should be 26)
argparse performs a complex formatting of the usage for argument grouping
and for line wrapping to fit the terminal width. This formatting has been
a constant source of bugs for at least 10 years (see linked issues below)
where defensive assertion errors are triggered or brackets and paranthesis
are not properly handeled.
Problem
=======
The current implementation of argparse usage formatting relies on regular
expressions to group arguments usage only to separate them again later
with another set of regular expressions. This is a complex and error prone
approach that caused all the issues linked below. Special casing certain
argument formats has not solved the problem. The following are some of
the most common issues:
- empty `metavar`
- mutually exclusive groups with `SUPPRESS`ed arguments
- metavars with whitespace
- metavars with brackets or paranthesis
Solution
========
The following two comments summarize the solution:
- https://github.com/python/cpython/issues/82091#issuecomment-1093832187
- https://github.com/python/cpython/issues/77048#issuecomment-1093776995
Mainly, the solution is to rewrite the usage formatting to avoid the
group-then-separate approach. Instead, the usage parts are kept separate
and only joined together at the end. This allows for a much simpler
implementation that is easier to understand and maintain. It avoids the
regular expressions approach and fixes the corresponding issues.
This closes the following GitHub issues:
- #62090
- #62549
- #77048
- #82091
- #89743
- #96310
- #98666
Eric Snow [Tue, 7 May 2024 04:21:51 +0000 (22:21 -0600)]
gh-117953: Always Run Extension Init Func in Main Interpreter First (gh-118157)
This change makes sure all extension/builtin modules have their init function run first by the main interpreter before proceeding with import in the original interpreter (main or otherwise). This means when the import of a single-phase init module fails in an isolated subinterpreter, it won't tie any global state/callbacks to the subinterpreter.
Brett Simmers [Tue, 7 May 2024 03:07:23 +0000 (20:07 -0700)]
gh-116322: Enable the GIL while loading C extension modules (#118560)
Add the ability to enable/disable the GIL at runtime, and use that in
the C module loading code.
We can't know before running a module init function if it supports
free-threading, so the GIL is temporarily enabled before doing so. If
the module declares support for running without the GIL, the GIL is
later disabled. Otherwise, the GIL is permanently enabled, and will
never be disabled again for the life of the current interpreter.
Sam Gross [Tue, 7 May 2024 00:12:39 +0000 (20:12 -0400)]
gh-118527: Intern code consts in free-threaded build (#118667)
We already intern and immortalize most string constants. In the
free-threaded build, other constants can be a source of reference count
contention because they are shared by all threads running the same code
objects.
Jelle Zijlstra [Mon, 6 May 2024 22:57:27 +0000 (15:57 -0700)]
gh-117486: Improve behavior for user-defined AST subclasses (#118212)
Now, such classes will no longer require changes in Python 3.13 in the normal case.
The test suite for robotframework passes with no DeprecationWarnings under this PR.
I also added a new DeprecationWarning for the case where `_field_types` exists
but is incomplete, since that seems likely to indicate a user mistake.
Dino Viehland [Mon, 6 May 2024 17:50:35 +0000 (10:50 -0700)]
gh-118362: Fix thread safety around lookups from the type cache in the face of concurrent mutators (#118454)
Add _PyType_LookupRef and use incref before setting attribute on type
Makes setting an attribute on a class and signaling type modified atomic
Avoid adding re-entrancy exposing the type cache in an inconsistent state by decrefing after type is updated
gh-71592: Add ability to trace Tcl commands executed by Tkinter (GH-118291)
This is an experimental feature, for internal use.
Setting tkinter._debug = True before creating the root window enables
printing every executed Tcl command (or a Tcl command equivalent to the
used Tcl C API).
This will help to convert a Tkinter example into Tcl script to check
whether the issue is caused by Tkinter or exists in the underlying Tcl/Tk
library.