Feature or enhancement

The steering council has PEP 703. This is intended as a top-level issue to keep track of integration status.

The "up for grabs" list contains issues that no one is currently working on and are ready to be implemented. If you are interested in working on one of them, please comment on the specific issue and CC me (@colesbury) on related PRs.

### Up For Grabs (comment on specific issue to take)

### Linked issues
- [ ] https://github.com/python/cpython/issues/111506
- [ ] https://github.com/python/cpython/issues/111870
- [ ] https://github.com/python/cpython/issues/111924
- [ ] https://github.com/python/cpython/issues/112606
- [ ] https://github.com/python/cpython/issues/114203
- [ ] https://github.com/python/cpython/issues/114214
- [ ] https://github.com/python/cpython/issues/115999
- [ ] https://github.com/python/cpython/issues/116024
- [ ] https://github.com/python/cpython/issues/116738
- [ ] https://github.com/python/cpython/issues/117139
- [ ] https://github.com/python/cpython/issues/117721
- [ ] https://github.com/python/cpython/issues/117657
- [ ] https://github.com/python/cpython/issues/119053

### Completed Issues
- [ ] https://github.com/python/cpython/issues/108223
- [ ] https://github.com/python/cpython/issues/108374
- [ ] https://github.com/python/cpython/issues/108337
- [ ] https://github.com/python/cpython/issues/108724
- [ ] https://github.com/python/cpython/issues/109549
- [ ] https://github.com/python/cpython/issues/109740
- [ ] https://github.com/python/cpython/issues/110119
- [ ] https://github.com/pypa/packaging/issues/727
- [ ] https://github.com/python/cpython/issues/111062
- [ ] https://github.com/python/cpython/issues/111569
- [ ] https://github.com/python/cpython/issues/112062
- [ ] https://github.com/python/cpython/issues/111903
- [ ] https://github.com/python/cpython/issues/111916
- [ ] https://github.com/python/cpython/issues/111928
- [ ] https://github.com/python/cpython/issues/112070
- [ ] https://github.com/python/cpython/issues/111956
- [ ] https://github.com/python/cpython/issues/111965
- [ ] https://github.com/python/cpython/issues/112213
- [ ] https://github.com/python/cpython/issues/112071
- [ ] https://github.com/python/cpython/issues/111972
- [ ] https://github.com/python/cpython/issues/112538
- [ ] https://github.com/python/cpython/issues/111962
- [ ] https://github.com/python/cpython/issues/112535
- [ ] https://github.com/python/cpython/issues/112205
- [ ] https://github.com/python/cpython/issues/111971
- [ ] https://github.com/python/cpython/issues/111650
- [ ] https://github.com/python/cpython/issues/113750
- [ ] https://github.com/python/cpython/issues/111964
- [ ] https://github.com/python/cpython/issues/113884
- [ ] https://github.com/python/cpython/issues/114569
- [ ] https://github.com/python/cpython/issues/114329
- [ ] https://github.com/python/cpython/issues/112066
- [ ] https://github.com/python/cpython/issues/110481
- [ ] https://github.com/python/cpython/issues/112532
- [ ] https://github.com/python/cpython/issues/112050
- [ ] https://github.com/python/cpython/issues/111968
- [ ] https://github.com/python/cpython/issues/115491
- [ ] https://github.com/python/cpython/issues/112175
- [ ] https://github.com/python/cpython/issues/113743
- [ ] https://github.com/python/cpython/issues/115103
- [ ] https://github.com/python/cpython/issues/112087
- [ ] https://github.com/python/cpython/issues/116616
- [ ] https://github.com/python/cpython/issues/116167
- [ ] https://github.com/python/cpython/issues/112536
- [ ] https://github.com/python/cpython/issues/116522
- [ ] https://github.com/python/cpython/issues/116664
- [ ] https://github.com/python/cpython/issues/117323
- [ ] https://github.com/python/cpython/issues/117300
- [ ] https://github.com/python/cpython/issues/111926
- [ ] https://github.com/python/cpython/issues/117293
- [ ] https://github.com/python/cpython/issues/117435
- [ ] https://github.com/python/cpython/issues/114271
- [ ] https://github.com/python/cpython/issues/112069
- [ ] https://github.com/python/cpython/issues/116329
- [ ] https://github.com/python/cpython/issues/116818
- [ ] https://github.com/python/cpython/issues/117514
- [ ] https://github.com/python/cpython/issues/112529
- [ ] https://github.com/python/cpython/issues/112075
- [ ] https://github.com/python/cpython/issues/116322

### Deferred tasks
- [ ] Revisit and update [`--disable-gil`](https://docs.python.org/dev/using/configure.html#cmdoption-disable-gil) configure documentation
- [x] Reenable test_cppext on `--disable-gil` builds
- [x] Audit usage of PyObject_Malloc for non-PyObject allocations
- [ ] Consider avoiding refcounting `tp_mro` during PyType_IsSubtype

Upstream functionality from nogil-3.12

This is a list of commits from the nogil-3.12 PR plan. The crossed-out entries are commits that do not need to be upstreamed, usually because the functionality is already in the main branch.

• cefe5dfee9 configure: disallow "--with-trace-refs" for "--disable-gil" builds
• Add support for thread sanitizer (TSAN) via --with-thread-sanitizer #112536)
• Add a mechanism to disable the GIL #116167)
• f30d8d8f50 Add pyatomic.h
• 385eb1d99c pyport: add new macros
• de2be447b3 Make PyThreadState_GET thread-local
• a24dc2ecc3 pystate: keep track of attached vs. detached state
• 4584be5950 parking_lot: add mutexes and one-time notifications
• Implement Python Critical Sections from PEP 703 #111569)
• Avoid changing the PYMEM_DOMAIN_RAW allocator during initialization and finalization #111924)
• Move the eval_breaker to PyThreadState #112175)
• b6b12a9a94 Implement biased reference counting
• Implement biased reference counting in --disable-gil builds #110481)
• 7b6b6f1a01 unicode: immortalize interned strings
• fc173e3711 unicode: always immortalize interned strings
• dd9b78460c Add safe memory reclamation scheme based on FreeBSD's GUS
• 901e134921 Add mimalloc v2.0.9 (DinoV)
• mimalloc: additional integration and changes for --disable-gil builds #112532)
• Avoid changing the PYMEM_DOMAIN_RAW allocator during initialization and finalization #111924)
• Make the garbage collector thread-safe in --disable-gil builds #112529)
• Make the garbage collector thread-safe in --disable-gil builds #112529)
• Implement stop-the-world functionality (for --disable-gil builds) #111964)
• Make the garbage collector thread-safe in --disable-gil builds #112529)
• Use stop-the-world to make fork and interpreter shutdown thread-safe #116522)
• Make sys.settrace, sys.setprofile, and sys.monitoring thread safe in --disable-gil builds #116818)
• Use stop-the-world to make sys._current_frames() and sys._current_exceptions() thread-safe in free-threaded build #117300)
• 86efa7dfe3 pystate: implement _PyRuntime.multithreaded
• Make dict objects thread-safe in --disable-gil builds #112075)
• Make list objects thread-safe in --disable-gil builds #112087)
• Make the MRO cache thread-safe in free-threaded builds #113743)
• Thread-safe one-time initialization #111956)
• Make weakref thread-safe without the GIL #111926)
• dtoa: thread safety in --disable-gil builds #111962)
• unicode: make _PyUnicode_FromId thread-safe in --disable-gil builds #111971)
• unicode: make ucnhash_capi initialization thread-safe in --disable-gil builds #111972)
• Make _threadmodule.c thread-safe in --disable-gil builds #114271)
• cfc11bcb1a typeobject: thread safety
• Make _threadmodule.c thread-safe in --disable-gil builds #114271)
• 74df7785f5 pyqueue: add internal queue data structure
• Add delayed reclamation mechanism for free-threaded build (QSBR) #115103)
• Make queue.SimpleQueue thread-safe in --disable-gil builds #113884)
• Make set thread-safe in --disable-gil builds #112069)
• 3cfbc49229 moduleobject: fix data races
• Make _threadmodule.c thread-safe in --disable-gil builds #114271)
• 31ec6f0290 pystate: refcount threads to handle race between interpreter shutdown and thread exit
• 45bdd27ee5 threading: make _thread.lock thread-safe
• Use per-thread freelists in --disable-gil builds #111968)
• ea1160c6d7 asyncio: fix race conditions in enter_task and leave_task
• Use PyDict_GetItemRef() #111789)
• Thread-safe one-time initialization #111956)
• socketmodule.c: use atomics to access defaulttimeout in free-threaded build  #116616)
• Make functools.lru_cache thread-safe in --disable-gil builds #112070)
• Make random.Random thread-safe in --disable-gil builds #112071)
• Argument Clinic: Add support for PEP 703's critical sections (Py_BEGIN_CRITICAL_SECTION()) #111903)
• Use critical sections to protect I/O objects (in --disable-gil builds) #111965)
• Use critical sections to protect I/O objects (in --disable-gil builds) #111965)
• Use critical sections to protect I/O objects (in --disable-gil builds) #111965)
• Make collections.deque thread-safe in --disable-gil builds #112050)
• 78825e0508 importlib: fix data race in imports (PyImport_ImportModuleLevelObject)
• Make multiprocessing SemLock thread-safe in the free-threaded build #117435)
• Make hashlib related modules thread-safe without the GIL #111916)
• Make _struct module thread-safe in --disable-gil builds #112062)
• 0e0b3899d1 signalmodule: fix thread-safety issue on macOS (Unclear if this is still an issue on macOS)
• json: make "memo" dict local to scan_once call #111928)
• 86e7772c64 http: fix dependency on finalization order
• 9ab96964e7 faulthandler: don't dump all threads when running without the GIL
• cff32694a4 test_gdb: skip test_threads when running without GIL
• 2ae5ee5ed4 tests: fix and work around some race conditions in tests
• 9f9b3d085f ceval: fix some thread-safety issues
• Use per-thread freelists in --disable-gil builds #111968)
• 149ea9dc43 Deferred reference counting
• 7e7568672d specialize: make specialization thread-safe
• 90d34f0d18 specialize: optimize for single-threaded programs
• 42d3e11d8c code: make code object use deferred reference counting
• c9fc49666c test: add support for checking for TSAN
• 7507a77a98 thread: don't use sem_clockwait with TSAN
• a62d37674c _posixsubprocess: disable vfork when running with ASAN
• 398204d57b object: fix reported TSAN races
• Disable the GIL by default in free-threaded builds #116329)

Linked PRs

• gh-108219: Add credits to free-threading project #123802
• [3.13] gh-108219: Add credits to the free-threading entry in What's New (GH-123802) #123847