Starting off with WASI version, WASI SDK version, and whether cooperative multithreading is available. All values are required as WASI SDK is the officially supported compiler according to PEP 11.
Remove Py_SetProgramName(), Py_SetPythonHome(), PySys_SetArgv() and
PySys_SetArgvEx() functions, deprecated since Python 3.11.
Mark the 4 functions as abi_only in stable_abi.toml.
No longer use deprecated Py_IgnoreEnvironmentFlag in Py_GETENV().
Instead, use PyConfig.use_environment when Python is initialized.
Modify also PySys_SetArgv() to use PyConfig.isolated when Python is
initialized.
* Check for signals more often. Previously, a pending exception could
be removed by PyErr_Clear().
* Only call _PyInterpreterState_SetNotRunningMain() if
_PyInterpreterState_SetRunningMain() has been called.
* Add pymain_error() and pyrun_error(): write the error message to
sys.stderr instead of the C stream stderr.
* Convert _PyPathConfig_UpdateGlobal() PyStatus error to an
exception.
* Simplify pymain_run_startup(): avoid strerror() which is decoded
from the wrong encoding. Instead display the exception, Py_fopen()
raises an OSError with the path object (and can raise other exceptions).
* Add pymain_set_path0() function.
* Add _PySys_FormatV() function.
PyConfig_Set() and sys.set_int_max_str_digits() now replace
sys.flags (create a new object), instead of modifying sys.flags in-place.
Modifying sys.flags in-place can lead to data races when multiple
threads are reading or writing sys.flags in parallel.
Use _Py_atomic functions to get and set max_str_digits members.
Co-authored-by: Bénédikt Tran <10796600+picnixz@users.noreply.github.com>
## Summary
- Move the `runtime->initialized = 1` store from before `site.py` import to the end of `init_interp_main()`, so `Py_IsInitialized()` only returns true after initialization has fully completed
- Access `initialized` and `core_initialized` through new inline accessors using acquire/release atomics, to also protect from data race undefined behavior
- `PySys_AddAuditHook()` now uses the accessor, so with the flag move it correctly skips audit hook invocation during all init phases (matching the documented "after runtime initialization" behavior) ... We could argue that running these earlier would be good even if the intent was never explicitly expressed, but that'd be its own issue.
## Motivation
`Py_IsInitialized()` returned 1 while `Py_InitializeEx()` was still running — specifically, before `site.py` had been imported. See https://github.com/PyO3/pyo3/issues/5900 where a second thread could acquire the GIL and start executing Python with an incomplete `sys.path` because `site.py` hadn't finished.
The flag was also a plain `int` with no atomic operations, making concurrent reads a C-standard data race, though unlikely to manifest.
## Regression test:
The added test properly fails on `main` with `ERROR: Py_IsInitialized() was true during site import`.
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Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
the lazy imports PEP initial implementation (3.15 alpha) inadvertently incremented the length of the sys.flags tuple. In a way that did not do anything useful or related to the lazy imports setting (it exposed sys.flags.gil in the tuple). This fixes that to hard code the length to the 3.13 & 3.14 released length of 18 and have our tests and code comments make it clear that we've since stopped making new sys.flags attributes available via sequence index.
Changing the values requires forking and patching, which is intentional. Simply rebuilding from source does not change the implementation enough to justify changing these values - they would still be `cpython` and compatible with existing `.pyc` files. But people who maintain forks are better served by being able to easily override these values in a place that can be forward-ported reliably.
Allow the --enable-pystats build option to be used with free-threading. The
stats are now stored on a per-interpreter basis, rather than process global.
For free-threaded builds, the stats structure is allocated per-thread and
then periodically merged into the per-interpreter stats structure (on thread
exit or when the reporting function is called). Most of the pystats related
code has be moved into the file Python/pystats.c.
Follow-up refactoring after GH-133143, where we use `_Py_ID` for "big" and "little"
in `abi_info.byteorder`.
This uses `_Py_ID` for `sys.byteorder`, but also `float_repr_style` and a module name.
This partially reverts #137047, keeping the tests for GC collectability of the
original class that dataclass adds `__slots__` to.
The reference leaks solved there are instead solved by having the `__dict__` &
`__weakref__` descriptors not tied to (and referencing) their class.
Instead, they're shared between all classes that need them (within
an interpreter).
The `__objclass__` ol the descriptors is set to `object`, since these
descriptors work with *any* object. (The appropriate checks were already
made in the get/set code, so the `__objclass__` check was redundant.)
The repr of these descriptors (and any others whose `__objclass__` is `object`)
now doesn't mention the objclass.
This change required adjustment of introspection code that checks
`__objclass__` to determine an object's “own” (i.e. not inherited) `__dict__`.
Third-party code that does similar introspection of the internals will also
need adjusting.
Co-authored-by: Jelle Zijlstra <jelle.zijlstra@gmail.com>
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.
Remove the `__dict__` and `__weakref__` descriptors from the original class when creating a dataclass from it.
An interesting hack, but more localized in scope than gh-135230.
This may be a breaking change if people intentionally keep the original class around
when using `@dataclass(slots=True)`, and then use `__dict__` or `__weakref__` on the
original class.
Co-authored-by: Alyssa Coghlan <ncoghlan@gmail.com>
Co-authored-by: Petr Viktorin <encukou@gmail.com>
Co-authored-by: Serhiy Storchaka <storchaka@gmail.com>
Make `warnings.catch_warnings()` use a context variable for holding
the warning filtering state if the `sys.flags.context_aware_warnings`
flag is set to true. This makes using the context manager thread-safe in
multi-threaded programs.
Add the `sys.flags.thread_inherit_context` flag. If true, starting a new
thread with `threading.Thread` will use a copy of the context
from the caller of `Thread.start()`.
Both these flags are set to true by default for the free-threaded build
and false for the default build.
Move the Python implementation of warnings.py into _py_warnings.py.
Make _contextvars a builtin module.
Co-authored-by: Kumar Aditya <kumaraditya@python.org>
Stan Ulbrych