Building CIL with CMake fails - no module called CIL

[lauramurgatroyd]

Description

This is due to cmake sometimes retrieving a python from outside the environment.
We have found this behaviour to happen on both linux and windows.

Investigation so far:

Environment

import cil, sys
print(cil.version.version, cil.version.commit_hash, sys.version, sys.platform)

[lauramurgatroyd]

In the combinations where it fails I can force it to get my python in my environment by setting the python executable:

cmake -S . -B ./build -DCMAKE_INSTALL_PREFIX=${CONDA_PREFIX} -DPython_EXECUTABLE=${CONDA_PREFIX}/bin/python