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![]() Make tuple iteration more thread-safe, and actually test concurrent iteration of tuple, range and list. (This is prep work for enabling specialization of FOR_ITER in free-threaded builds.) The basic premise is: Iterating over a shared iterable (list, tuple or range) should be safe, not involve data races, and behave like iteration normally does. Using a shared iterator should not crash or involve data races, and should only produce items regular iteration would produce. It is not guaranteed to produce all items, or produce each item only once. (This is not the case for range iteration even after this PR.) Providing stronger guarantees is possible for some of these iterators, but it's not always straight-forward and can significantly hamper the common case. Since iterators in general aren't shared between threads, and it's simply impossible to concurrently use many iterators (like generators), better to make sharing iterators without explicit synchronization clearly wrong. Specific issues fixed in order to make the tests pass: - List iteration could occasionally fail an assertion when a shared list was shrunk and an item past the new end was retrieved concurrently. There's still some unsafety when deleting/inserting multiple items through for example slice assignment, which uses memmove/memcpy. - Tuple iteration could occasionally crash when the iterator's reference to the tuple was cleared on exhaustion. Like with list iteration, in free-threaded builds we can't safely and efficiently clear the iterator's reference to the iterable (doing it safely would mean extra, slow refcount operations), so just keep the iterable reference around. |
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.. | ||
build | ||
buildbot | ||
c-analyzer | ||
cases_generator | ||
clinic | ||
freeze | ||
ftscalingbench | ||
gdb | ||
i18n | ||
importbench | ||
jit | ||
lockbench | ||
msi | ||
nuget | ||
patchcheck | ||
peg_generator | ||
scripts | ||
ssl | ||
tsan | ||
tz | ||
unicode | ||
unittestgui | ||
wasm | ||
README | ||
requirements-dev.txt | ||
requirements-hypothesis.txt |
This directory contains a number of Python programs that are useful while building or extending Python. build Automatically generated directory by the build system contain build artifacts and intermediate files. buildbot Batchfiles for running on Windows buildbot workers. c-analyzer Tools to check no new global variables have been added. cases_generator Tooling to generate interpreters. clinic A preprocessor for CPython C files in order to automate the boilerplate involved with writing argument parsing code for "builtins". freeze Create a stand-alone executable from a Python program. gdb Python code to be run inside gdb, to make it easier to debug Python itself (by David Malcolm). i18n Tools for internationalization. pygettext.py parses Python source code and generates .pot files, and msgfmt.py generates a binary message catalog from a catalog in text format. importbench A set of micro-benchmarks for various import scenarios. msi Support for packaging Python as an MSI package on Windows. nuget Files for the NuGet package manager for .NET. patchcheck Tools for checking and applying patches to the Python source code and verifying the integrity of patch files. peg_generator PEG-based parser generator (pegen) used for new parser. scripts A number of useful single-file programs, e.g. run_tests.py which runs the Python test suite. ssl Scripts to generate ssl_data.h from OpenSSL sources, and run tests against multiple installations of OpenSSL and LibreSSL. tz A script to dump timezone from /usr/share/zoneinfo. unicode Tools for generating unicodedata and codecs from unicode.org and other mapping files (by Fredrik Lundh, Marc-Andre Lemburg and Martin von Loewis). unittestgui A Tkinter based GUI test runner for unittest, with test discovery. wasm Config and helpers to facilitate cross compilation of CPython to WebAssembly (WASM). Note: The pynche color editor has moved to https://gitlab.com/warsaw/pynche