This PR fixes undefined behaviour in the struct module unpacking support functions `bu_longlong`, `lu_longlong`, `bu_int` and `lu_int`; thanks to @kumaraditya303 for finding these.
The fix is to accumulate the bytes in an unsigned integer type instead of a signed integer type, then to convert to the appropriate signed type. In cases where the width matches, that conversion will typically be compiled away to a no-op.
(Evidence from Godbolt: https://godbolt.org/z/5zvxodj64 .)
To make the conversions efficient, I've specialised the relevant functions for their output size: for `bu_longlong` and `lu_longlong`, this only entails checking that the output size is indeed `8`. But `bu_int` and `lu_int` were used for format sizes `2` and `4` - I've split those into two separate functions each.
No tests, because all of the affected cases are already exercised by the test suite.
This is a preliminary PR to refactor `PyLong_FromString` which is currently quite messy and has spaghetti like code that mixes up different concerns as well as duplicating logic.
In particular:
- `PyLong_FromString` now only handles sign, base and prefix detection and calls a new function `long_from_string_base` to parse the main body of the string.
- The `long_from_string_base` function handles all string validation and then calls `long_from_binary_base` or a new function `long_from_non_binary_base` to construct the actual `PyLong`.
- The existing `long_from_binary_base` function is simplified by factoring duplicated logic to `long_from_string_base`.
- The new function `long_from_non_binary_base` factors out much of the code from `PyLong_FromString` including in particular the quadratic algorithm reffered to in gh-95778 so that this can be seen separately from unrelated concerns such as string validation.
HTTP links in the "HISTORY OF THE SOFTWARE" section of Doc/license.rst
were converted to HTTPS in f62ff97f31.
But there were other copies of these links, which were left HTTP links.
Only call tkinter.tk and its follow-up code in _init_tk_type when requires('gui')
does not raise. This function can be called as an unintended side-effect of
calling other idlelib code as part of tests on macOS without a GUI enabled.
The main problem was that an unluckily timed task cancellation could cause
the semaphore to be stuck. There were also doubts about strict FIFO ordering
of tasks allowed to pass.
The Semaphore implementation was rewritten to be more similar to Lock.
Many tests for edge cases (including cancellation) were added.
They were undertested, and since #96954 might involve a
rewrite of this part of the code we want to ensure that
there won't be any behavioral change.
Co-authored-by: Carl Friedrich Bolz-Tereick <cfbolz@gmx.de>
At Python exit, sometimes a thread holding the GIL can wait forever
for a thread (usually a daemon thread) which requested to drop the
GIL, whereas the thread already exited. To fix the race condition,
the thread which requested the GIL drop now resets its request before
exiting.
take_gil() now calls RESET_GIL_DROP_REQUEST() before
PyThread_exit_thread() if it called SET_GIL_DROP_REQUEST to fix a
race condition with drop_gil().
Issue discovered and analyzed by Mingliang ZHAO.
This reverts commit 0587810698.
Reason: This broke buildbots (some warnings added by that commit are turned to errors in the SSL buildbot).
Repro: ./python Lib/test/ssltests.py
- Improve error message when parameter without a default follows one with a default
- Show same error message when positional-only params precede the default/non-default sequence
Warn on loop initialization, when setting the wakeup fd disturbs a previously set wakeup fd, and on loop closing, when upon resetting the wakeup fd, we find it has been changed by someone else.
Mark Dickinson
Oscar Benjamin
Serhiy Storchaka
Terry Jan Reedy
Michael Droettboom
Steve Dower
Stanley
Dong-hee Na
Jeff Allen
Kumar Aditya
Cyker Way
Brandt Bucher
Harry
partev
Batuhan Taskaya
Nikita Sobolev
wim glenn
Виталий Дмитриев
Samuel
Irit Katriel
serge-sans-paille
Vinay Sajip
Gregory P. Smith
Victor Stinner
Shantanu
C.A.M. Gerlach
Matthias Görgens
Raymond Hettinger
Scott Main
Guido van Rossum
Lysandros Nikolaou
Michel Hidalgo
Christian Heimes
Benjamin Peterson