plans to support build with Limited C API

[stanislavlevin]

Extensions built with a specific Limited API version can be compiled once and will be compatible with any newer interpreter of the same major version.

https://docs.python.org/3/c-api/stable.html
https://peps.python.org/pep-0652/#stable-abi-vs-limited-api
https://cython.readthedocs.io/en/latest/src/userguide/limited_api.html

Are there any plans to support build with Limited C API?

[jborean93]

I am hoping to get to it one day but was limited in the past by Cython as well as trying to specify a specific Cython version in pyproject.toml. Now that Cython supports it and we set an explicit build version rather than a range this is definitely more feasible to achieve.

IIRC we can't use the earlier limited API due to some missing buffer APIs but the 3.11 or somethign around that should be possible.

Out of curiosity is there a reason why you would want this? Outside of macOS or Windows we don't build wheels so using Linux wouldn't see too many advantages.

[stanislavlevin]

Out of curiosity is there a reason why you would want this? Outside of macOS or Windows we don't build wheels so using Linux wouldn't see too many advantages.

Extension built with Limited API for Python 3.x works for Python 3.x+ without recompiling.
In ALTLinux we would not need to rebuild extensions on every minor update of CPython.

Btw, python-gssapi 1.10.1 can be built successfully with Limited API 3.13 without any changes.

[jborean93]

Thanks for sharing an example where it'll help for you on Linux.

I've started to add support for the limited API/stable ABI on the Python krb5 library with this PR. I've also added experimental free-threading support with this. This Python library is essentially this module but for the krb5 C API but because it's less used I'm using it as a testing ground for those changes before implementing it here.