Skip to content

gh-160749: Correct documentation of tp_alloc and tp_free inheritance for heap types #160821

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Open
Yuvansh-thx wants to merge 2 commits into
base: main
Choose a base branch
from
+17 −10
Open

gh-160749: Correct documentation of tp_alloc and tp_free inheritance for heap types #160821

Changes from all commits
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
08cf8ab
docs: update inheritance and default rules for tp_alloc and tp_free s…
Yuvansh-thx Oct 28, 2026
1e2cd0f
Merge branch 'python:main' into main
Yuvansh-thx Oct 28, 2026
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
27 changes: 17 additions & 10 deletions Doc/c-api/typeobj.rst
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -2138,17 +2138,21 @@ and :c:data:`PyType_Type` effectively act as defaults.)

**Inheritance:**

Static subtypes inherit this slot, which will be
Subtypes inherit this slot, which will be
:c:func:`PyType_GenericAlloc` if inherited from :class:`object`.

:ref:`Heap subtypes <heap-types>` do not inherit this slot.
Exception: Subtypes created using the :keyword:`class` statement or
calling :py:class:`type() <type>` do not inherit this slot.

**Default:**

For heap subtypes, this field is always set to
For subtypes created using the :keyword:`class` statement or
calling :py:class:`type() <type>`, this field is always set to
:c:func:`PyType_GenericAlloc`.

For static subtypes, this slot is inherited (see above).
For other subtypes (including :ref:`static types <static-types>` and
:ref:`heap types <heap-types>` created via :c:func:`PyType_FromSpec`),
this slot is inherited (see above).


.. c:member:: newfunc PyTypeObject.tp_new
Expand Down Expand Up @@ -2205,22 +2209,25 @@ and :c:data:`PyType_Type` effectively act as defaults.)

**Inheritance:**

Static subtypes inherit this slot, which will be :c:func:`PyObject_Free` if
Subtypes inherit this slot, which will be :c:func:`PyObject_Free` if
inherited from :class:`object`. Exception: If the type supports garbage
collection (i.e., the :c:macro:`Py_TPFLAGS_HAVE_GC` flag is set in
:c:member:`~PyTypeObject.tp_flags`) and it would inherit
:c:func:`PyObject_Free`, then this slot is not inherited but instead defaults
to :c:func:`PyObject_GC_Del`.

:ref:`Heap subtypes <heap-types>` do not inherit this slot.
Exception: Subtypes created using the :keyword:`class` statement or
calling :py:class:`type() <type>` do not inherit this slot.

**Default:**

For :ref:`heap subtypes <heap-types>`, this slot defaults to a deallocator suitable to match
:c:func:`PyType_GenericAlloc` and the value of the
:c:macro:`Py_TPFLAGS_HAVE_GC` flag.
For subtypes created using the :keyword:`class` statement or
calling :py:class:`type() <type>`, this field is always set to
:c:func:`PyObject_GC_Del`.

For static subtypes, this slot is inherited (see above).
For other subtypes (including :ref:`static types <static-types>` and
:ref:`heap types <heap-types>` created via :c:func:`PyType_FromSpec`),
this slot is inherited (see above).


.. c:member:: inquiry PyTypeObject.tp_is_gc
Expand Down
Loading