Use CMake 3.12+ PYBIND11_FINDPYTHON

[devw4r]

• https://pybind11.readthedocs.io/en/stable/faq.html?highlight=cmake#cmake-doesn-t-detect-the-right-python-version

Not sure if this is the right place to put this.

[namreeb]

Looks fine to me. @gtker thoughts?

[devw4r]

Not sure why linux build fails, any ideas?

[gtker]

I'll try to investigate the Linux issue.

Why is enabling PYBIND11_FINDPYTHON necessary? Are the wheels not using the correct Python versions?

[gtker]

@devw4r

It seems like this is a known issue reported in pybind/pybind11#4802, and scikit-build/scikit-build-core#472.

The problem seems to be that manylinux doesn't ship Development.Embed. There seems to be three ways to fix this on Linux:

1. Add AND NOT UNIX to ${CMAKE_VERSION} VERSION_GREATER "3.12.0".
2. Put find_package(Python3 REQUIRED COMPONENTS Interpreter Development.Module) inside the CMake version if statement that you added, just before add_subdirectory(pybind11).
3. Update pybind11 to the commit in this open pull request.

I'm guessing the changes in this PR are related to Windows, if that's the case I would just add AND NOT UNIX to disable it for Apple/Linux since I haven't had any issues finding Python.

[devw4r]

This PR was made for Linux, which was resolving 3.10 instead of 3.11.5.

[gtker]

How do I verify that the problem has been fixed?

[devw4r]

How do I verify that the problem has been fixed?

Not sure how to test, for me, adding this PR fixed python resolving locally.

Before:

After:

[gtker]

How do I verify that the problem has been fixed?

Not sure how to test, for me, adding this PR fixed python resolving locally.

I'm not sure if that's so much a bug as it's just the CMake scripts having different priorities. For me on Ubuntu 22.04 with python3, python3-dev, python3.11, and python3.11-dev packages installed CMake consistently picks the 3.11 version over the default 3.10.

I'm actually unsure of what the intended way of choosing the Python version is, since most ways seem to just be to set the required Python3_* variables to the specific version which is a little hacky.