PYBIND11_FINDPYTHON=ON

Reuse our `find_package(Python ...)` call and use new CMake logic in
pybind11.
https://pybind11.readthedocs.io/en/stable/compiling.html#modules-with-cmake

Signed-off-by: Axel Huebl <axel.huebl@plasma.ninja>

cmake/dependencies/pybind11.cmake

@@ -16,6 +16,11 @@ function(find_pybind11)
             message(STATUS "pybind11 repository: ${openPMD_pybind11_repo} (${openPMD_pybind11_branch})")
         endif()
     endif()
+
+    # rely on our find_package(Python ...) call
+    # https://pybind11.readthedocs.io/en/stable/compiling.html#modules-with-cmake
+    set(PYBIND11_FINDPYTHON ON)
+
     if(TARGET pybind11::module)
         # nothing to do, target already exists in the superbuild
     elseif(openPMD_USE_INTERNAL_PYBIND11 AND openPMD_pybind11_src)

setup.py

@@ -49,7 +49,6 @@ def build_extension(self, ext):
             os.path.join(extdir, "openpmd_api"),
             # '-DCMAKE_RUNTIME_OUTPUT_DIRECTORY=' + extdir,
             '-DopenPMD_PYTHON_OUTPUT_DIRECTORY=' + extdir,
-            '-DPython_EXECUTABLE=' + sys.executable,
             '-DopenPMD_USE_PYTHON:BOOL=ON',
             # variants
             '-DopenPMD_USE_MPI:BOOL=' + openPMD_USE_MPI,