Two special methods, __buffer__ and __release_buffer__ were added to
Python 3.12 by PEP 688. The C API Type Object documentation for slots
includes `tp_as_buffer`, and sub-slots `bf_getbuffer`, `bf_releasebuffer`
but does not refer to the Python Data Model version of those. Add the
missing references.
* Add "cyclic isolate" to the glossary.
* Add a new "Object Life Cycle" page.
* Improve docs for related API, with special focus on cross-references and warnings
Co-authored-by: Petr Viktorin <encukou@gmail.com>
Co-authored-by: Peter Bierma <zintensitydev@gmail.com>
After gh-130704, the interpreter replaces some uses of `LOAD_FAST` with
`LOAD_FAST_BORROW` which avoid incref/decrefs by "borrowing" references
on the interpreter stack when the bytecode compiler can determine that
it's safe.
This change broke some checks in C API extensions that relied on
`Py_REFCNT()` of `1` to determine if it's safe to modify an object
in-place. Objects may have a reference count of one, but still be
referenced further up the interpreter stack due to borrowing of
references.
This provides a replacement function for those checks.
`PyUnstable_Object_IsUniqueReferencedTemporary` is more conservative:
it checks that the object has a reference count of one and that it exists as a
unique strong reference in the interpreter's stack of temporary
variables in the top most frame.
See also:
* https://github.com/numpy/numpy/issues/28681
Co-authored-by: Pieter Eendebak <pieter.eendebak@gmail.com>
Co-authored-by: T. Wouters <thomas@python.org>
Co-authored-by: mpage <mpage@cs.stanford.edu>
Co-authored-by: Mark Shannon <mark@hotpy.org>
Co-authored-by: Victor Stinner <vstinner@python.org>
* Skip sNaN's testing in 32-bit mode.
* Drop float_set_snan() helper.
* Use memcpy() workaround for sNaN's in PyFloat_Unpack4().
* Document, that sNaN's may not be preserved by PyFloat_Pack/Unpack API.
We replace it with _Py_GetMainModule(), and add _Py_CheckMainModule(), but both in the internal-only C-API. We also add _PyImport_GetModulesRef(), which is the equivalent of _PyImport_GetModules(), but which increfs before the lock is released.
This is used by a later change related to pickle and handling __main__.
If `Py_IsFinalizing()` is true, non-daemon threads (other than the current one)
are done, and daemon threads are prevented from running, so they
cannot finalize themselves and become done. Joining them (without timeout)
would block forever.
Raise PythonFinalizationError instead of hanging.
Raise even when a timeout is given, for consistency with trying to join your own thread.
See gh-123940 for a use case: calling `join()` from `__del__`. This is
ill-advised, but an exception should at least make it easier to diagnose.
Non-tuple sequences are deprecated as argument for the "(items)" format unit
in PyArg_ParseTuple() and other argument parsing functions if items contains
format units which store borrowed buffer or reference (e.g. "s" and "O").
str and bytearray are no longer accepted as valid sequences.
Docs of the other `PyType_From*` functions link to `PyType_FromMetaclass`,
which noted that they differ for backwards compatibility reasons.
The note is no longer relevant in 3.14.
The other functions have `versionchanged` blurbs.
The tp_finalize C API doc used PyErr_Fetch() and PyErr_Restore() in
its example code. That API was deprecated in 3.12.
Update to point to the suggested replacement function
PyErr_GetRaisedException() which has a sample usage.
The "Type Objects" title in `c-api/typeobj.rst`, duplicating the title of `c-api/type.rst`,
has been changed to "Type Objects Structures", thereby slightly improving Sphinx
search.
* Update documentation for tp_basicsize & tp_itemsize
- Add alignment requirement
- Mention that ob_size is unreliable if you don't control it
- Add some links for context
- basicsize should include the base type in generaly not just PyObject
This adds a “by-the-way” link to `PyObject_New`, which shouldn't be
used for GC types. In order to be comfortable linking to it, I also
add a link to `PyObject_GC_New` from its docs. And the same for
`*Var` variants, while I'm here.
* Strongly suggest Py_SIZE & Py_SET_SIZE
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`.
