pybind finds old versions of python

[jcoulter12]

Hi xfac developers,

Because of this issue with pybind11:

pybind/pybind11#4785

when installing xfac python bindings, it's possible to have the .so file in build/python stuck using an undesired version of python.

I'm just opening an issue to let you know that this can be easily worked around by modifying extern/pybind11/CMakeLists.txt to add two lines with a version of python higher than the undesired version (for example, in my case I was getting stuck with python 3.6 even though which python provided python 3.10).

if(NOT CMAKE_VERSION VERSION_LESS "3.27")
  find_package(PythonInterp 3.10 REQUIRED)
  find_package(PythonLibs 3.10 REQUIRED)
  cmake_policy(GET CMP0148 _pybind11_cmp0148)
endif()

You may find a better way, but just in case I think it is worth mentioning this in case it affects other users. Feel free to close the issue once you've noted it.
Best,
Jenny

[yurielnf]

Hi Jenny,

Thanks for fixing this! Did you try with set(PYBIND11_FINDPYTHON ON) as they explain in the pybind11 issue?

Best,
Yuriel

[jcoulter12]

Hi Yuriel,

Thanks for looking more closely -- you're right, adding that line instead of the two I proposed also works. That would be a nicer fix, definitely.

Best,
Jenny

[yurielnf]

Nice! Another question: if I put the fix at line 26 of extern/extern.cmake instead, does it work?
It would be a clean solution since we should not modify the pybind11 repo.
In this case you can make a PR for your contribution to remains.
Thanks!

[jcoulter12]

Yes, I think that also works. Great to find a solution which is not sticking these lines in pybind, I agree.
Best,
Jenny