I chose to not raise an exception here because I think it would be
confusing for module attribute access to start raising something other
than AttributeError if e.g. the cwd goes away
Without the change in moduleobject.c
```
./python.exe -m unittest test.test_import.ImportTests.test_script_shadowing_stdlib_cwd_failure
...
Assertion failed: (PyErr_Occurred()), function _PyObject_SetAttributeErrorContext, file object.c, line 1253.
```
Fix `test_list.ListTest.test_no_memory` under trace refs build
Memory allocation ends up failing in _PyRefchainTrace(), which produces
different output. Assert that we don't segfault, which is the thing
we want to test and is less brittle than checking output.
The PyThreadState field gains a reference count field to avoid
issues with PyThreadState being a dangling pointer to freed memory.
The refcount starts with a value of two: one reference is owned by the
interpreter's linked list of thread states and one reference is owned by
the OS thread. The reference count is decremented when the thread state
is removed from the interpreter's linked list and before the OS thread
calls `PyThread_hang_thread()`. The thread that decrements it to zero
frees the `PyThreadState` memory.
The `holds_gil` field is moved out of the `_status` bit field, to avoid
a data race where on thread calls `PyThreadState_Clear()`, modifying the
`_status` bit field while the OS thread reads `holds_gil` when
attempting to acquire the GIL.
The `PyThreadState.state` field now has `_Py_THREAD_SHUTTING_DOWN` as a
possible value. This corresponds to the `_PyThreadState_MustExit()`
check. This avoids race conditions in the free threading build when
checking `_PyThreadState_MustExit()`.
This adds two new methods to `multiprocessing`'s `ProcessPoolExecutor`:
- **`terminate_workers()`**: forcefully terminates worker processes using `Process.terminate()`
- **`kill_workers()`**: forcefully kills worker processes using `Process.kill()`
These methods provide users with a direct way to stop worker processes without `shutdown()` or relying on implementation details, addressing situations where immediate termination is needed.
Co-authored-by: Bénédikt Tran <10796600+picnixz@users.noreply.github.com>
Co-authored-by: blurb-it[bot] <43283697+blurb-it[bot]@users.noreply.github.com>
Co-authored-by: Sam Gross @colesbury
Commit-message-mostly-authored-by: Claude Sonnet 3.7 (because why not -greg)
* Fix use after free in list objects
Set the items pointer in the list object to NULL after the items array
is freed during list deallocation. Otherwise, we can end up with a list
object added to the free list that contains a pointer to an already-freed
items array.
* Mark `_PyList_FromStackRefStealOnSuccess` as escaping
I think technically it's not escaping, because the only object that
can be decrefed if allocation fails is an exact list, which cannot
execute arbitrary code when it is destroyed. However, this seems less
intrusive than trying to special cases objects in the assert in `_Py_Dealloc`
that checks for non-null stackpointers and shouldn't matter for performance.
The bytecode compiler only generates a few different types of constants,
like str, int, tuple, slices, etc. Users can construct code objects with
various unusual constants, including ones that are not hashable or not
even constant.
The free threaded build previously crashed with a fatal error when
confronted with these constants. Instead, treat distinct objects of
otherwise unhandled types as not equal for the purposes of deduplication.
* Add location information when accessing already closed stackref
* Add #def option to track closed stackrefs to provide precise information for use after free and double frees.
Fix a race condition in test_check_output_timeout() of
test_subprocess. Don't write into stdout anymore, since there is no
reliable way to synchronize the parent and the child processes.
Change the timeout from 3 seconds to 0.1 seconds, and remove
@requires_resource('walltime') decorator.
Disable pedantic check for c++03 (unlimited API)
Also add a check for c++03 *limited* API, which passes in pedantic mode
after removing a comma in the `PySendResult` declaration, and allowing
`long long`.
