_PyRawMutex_UnlockSlow CAS-removes the waiter from the list and then
calls _PySemaphore_Wakeup, with no handshake. If _PySemaphore_Wait
returns Py_PARK_INTR, the waiter can destroy its stack-allocated
semaphore before the unlocker's Wakeup runs, causing a fatal error from
ReleaseSemaphore / sem_post.
Loop in _PyRawMutex_LockSlow until _PySemaphore_Wait returns Py_PARK_OK,
which is only signalled when a matching Wakeup has been observed.
Also include GetLastError() and the handle in the Windows fatal messages
in _PySemaphore_Init, _PySemaphore_Wait, and _PySemaphore_Wakeup to make
similar races easier to diagnose in the future.
(cherry picked from commit ad3c5b7958)
(cherry picked from commit d496c637a3)
Forbid marshalling recursive code objects which
cannot be correctly unmarshalled.
Add multiple tests for recursive data structures.
(cherry picked from commit 2e37d83641)
* gh-142183: Cache one datachunk per tstate to prevent alloc/dealloc thrashing (GH-145789) (#145828)
Cache one datachunk per tstate to prevent alloc/dealloc thrashing when repeatedly hitting the same call depth at exactly the wrong boundary.
Move new _ts member to the end to not mess up remote debuggers' ideas of the
struct's layout. (The struct is only created by the runtime, and the new
field only used by the runtime, so it should be safe.)
(cherry picked from commit 706fd4ec08)
(cherry picked from commit 19cbcc0f85)
Co-authored-by: blurb-it[bot] <43283697+blurb-it[bot]@users.noreply.github.com>
Co-authored-by: Miss Islington (bot) <31488909+miss-islington@users.noreply.github.com>
Weakrefs to unreachable garbage that are created during running of
finalizers need to be cleared. This avoids exposing objects that
have `tp_clear` called on them to Python-level code.
(cherry picked from commit b6b99bf7f1)
Co-authored-by: Neil Schemenauer <nas-github@arctrix.com>
* sort `--help-env` sections by environment variable name
Only needed in the first section, in 3.13 the second section was already sorted.
* regression test for --help-env & --help-xoptions sort order
Manual backport of GH-145997
gh-143650: Fix importlib race condition on import failure (GH-143651)
Fix a race condition where a thread could receive a partially-initialized
module when another thread's import fails. The race occurs when:
1. Thread 1 starts importing, adds module to sys.modules
2. Thread 2 sees the module in sys.modules via the fast path
3. Thread 1's import fails, removes module from sys.modules
4. Thread 2 returns a stale module reference not in sys.modules
The fix adds verification after the "skip lock" optimization in both Python
and C code paths to check if the module is still in sys.modules. If the
module was removed (due to import failure), we retry the import so the
caller receives the actual exception from the import failure rather than
a stale module reference.
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
cherry picked from ac8b5b6890
gh-144194: Fix mmap failure check in perf_jit_trampoline.c (#143713)
mmap() returns MAP_FAILED ((void*)-1) on error, not NULL. The current
check never detects mmap failures, so jitdump initialization proceeds
even when the memory mapping fails.
(cherry picked from commit 8fe8a94a7c)
Co-authored-by: stratakis <cstratak@redhat.com>
gh-142779: Initialize reserved field for proper padding (GH-142780)
The jitdump specification specifies a reserved field for padding.
Initialize it so no garbage data is embedded in the jitdump files.
(cherry picked from commit 77bf4ba732)
Co-authored-by: stratakis <cstratak@redhat.com>
Writing out an object may involve a slot lookup, which is not safe to do with
an exception raised. In debug mode an assertion failure will occur if this
happens.
(cherry picked from commit ce8f5f98c6)
Co-authored-by: Duane Griffin <duaneg@dghda.com>
[3.14] gh-143547: Fix PyErr_FormatUnraisable() fallback (GH-143557) (GH-143603)
gh-143547: Fix PyErr_FormatUnraisable() fallback (GH-143557)
Hold a strong reference to 'hook' while calling the default
unraisable took to log hook failure.
(cherry picked from commit 1d0baf1ae4)
(cherry picked from commit 39a2bcf949)
Co-authored-by: Victor Stinner <vstinner@python.org>
gh-142873: Do not check for `PyContextVar_CheckExact` twice in `PyContextVar_Set` (GH-142874)
(cherry picked from commit e61a447d0e)
Co-authored-by: sobolevn <mail@sobolevn.me>
[3.13] gh-142048: Fix lost gc allocations count on thread cleanup (GH-142233)
(cherry picked from commit 49b1fb43f6)
Co-authored-by: Kevin Wang <kevmo314@gmail.com>
The GC for the free threaded build would get slower with each collection due
to effectively double counting objects freed by the GC.
(cherry picked from commit eb892868b3)
Co-authored-by: Kevin Wang <kevmo314@gmail.com>
If we overflowed the global version counter (i.e., after 2*24 calls to
`_PyMonitoring_SetEvents`), we bailed out after setting global monitoring
events but before instrumenting code objects, which led to assertion errors
later on.
Also add a `time.sleep()` to `test_free_threading.test_monitoring` to avoid
overflowing the global version counter.
(cherry picked from commit e457d60daa)
gh-140530: fix a reference leak in an error path for `raise exc from cause` (#140908)
Fix a reference leak in `raise E from T` when `T` is an exception
subtype for which `T.__new__` does not return an exception instance.
(cherry picked from commit 0c77e7c23b)
gh-140815: Fix faulthandler for invalid/freed frame (#140921)
faulthandler now detects if a frame or a code object is invalid or
freed.
Add helper functions:
* _PyCode_SafeAddr2Line()
* _PyFrame_SafeGetCode()
* _PyFrame_SafeGetLasti()
_PyMem_IsPtrFreed() now detects pointers in [-0xff, 0xff] range
as freed.
(cherry picked from commit a84181c31b)
Revert GH-131993.
Fix swallowing some syntax warnings in different modules if they accidentally
have the same message and are emitted from the same line.
Fix duplicated warnings in the "finally" block.
(cherry picked from commit 279db6bede)
There were a few thread-safety issues when profiling or tracing all
threads via PyEval_SetProfileAllThreads or PyEval_SetTraceAllThreads:
* The loop over thread states could crash if a thread exits concurrently
(in both the free threading and default build)
* The modification of `c_profilefunc` and `c_tracefunc` wasn't
thread-safe on the free threading build.
(cherry picked from commit a10152f8fd)
* [3.13] gh-139748: fix leaks in AC error paths when using unicode FS-based converters (GH-139765)
(cherry picked from commit b04a57deef)
Co-authored-by: Bénédikt Tran <10796600+picnixz@users.noreply.github.com>
Miss Islington (bot)