Make PY_SSIZE_T_CLEAN not mandatory again

Feature or enhancement

Use ssize_t version API regardless PY_SSIZE_T_CLEAN is defined.

No change to ABI.

Pitch

After Python 3.12 become EOL, extension developers can forget about PY_SSIZE_T_CLEAN completely.

Previous discussion

https://mail.python.org/archives/list/python-dev@python.org/thread/KSREO43D6GQWO5LMVIU2LF7CP4IBYT2C/#FG44N6RL5CT5O3XQ6UV6LBLUCET7IF6I

Linked PRs

gh-104922: Make `PY_SSIZE_T_CLEAN` not mandatory again (#105051)

After Python 3.12 become EOL, extension developers can forget about PY_SSIZE_T_CLEAN completely.

Python stdlib extensions still define the PY_SSIZE_T_CLEAN macro. Is it still useful? It's unclear to me.

Also, the official documentation also requires to define the PY_SSIZE_T_CLEAN macro: https://docs.python.org/dev/extending/extending.html

The first two lines of our file can be:

#define PY_SSIZE_T_CLEAN
#include <Python.h>

(...)

It is recommended to always define PY_SSIZE_T_CLEAN before including Python.h.

See right after the doc. I added the link to https://docs.python.org/dev/c-api/arg.html#arg-parsing-string-and-buffers

And there is a note about it at link target.

Note On Python 3.12 and older, the macro PY_SSIZE_T_CLEAN must be defined before including Python.h to use all # variants of formats (s#, y#, etc.) explained below. This is not necessary on Python 3.13 and later.

I didn't remove the recommendation because user may want to support older Pythons.

Python stdlib extensions still define the PY_SSIZE_T_CLEAN macro. Is it still useful? It's unclear to me.

I didn't remove them to ease review and avoid conflicts. But I will remove them all.

The (extension) doc should just explain that the macro was needed on Python 3.12 and older.

gh-104922: remove PY_SSIZE_T_CLEAN (#106315)

gh-104922: Doc: add note about PY_SSIZE_T_CLEAN (#106314)

Merge branch 'main' into modulelocals

As a side effect, this change fixed the stable ABI: #71686. Thanks!

Add declarations for private functions from pycore_modsupport

remove some stuff

Add declarations for private functions from pycore_modsupport

Navigation Menu

Make PY_SSIZE_T_CLEAN not mandatory again #104922

Feature or enhancement

Pitch

Previous discussion

Linked PRs

Metadata

Assignees

Labels

Projects

Milestone

Relationships

Development

Make PY_SSIZE_T_CLEAN not mandatory again #104922

Description

Feature or enhancement

Pitch

Previous discussion

Linked PRs

Activity

vstinner commented on Jul 1, 2023

methane commented on Jul 1, 2023

vstinner commented on Jul 1, 2023

vstinner commented on Jan 16, 2024

Metadata

Metadata

Assignees

Labels

Projects

Milestone

Relationships

Development

Issue actions