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

@@ -10,6 +10,11 @@ function(find_pybind11)
         message(STATUS "pybind11 repository: ${ImpactX_pybind11_repo} (${ImpactX_pybind11_branch})")
         include(FetchContent)
     endif()
+
+    # rely on our find_package(Python ...) call
+    # https://pybind11.readthedocs.io/en/stable/compiling.html#modules-with-cmake
+    set(PYBIND11_FINDPYTHON ON)
+
     if(ImpactX_pybind11_internal OR ImpactX_pybind11_src)
         set(CMAKE_POLICY_DEFAULT_CMP0077 NEW)
 

setup.py

@@ -78,7 +78,6 @@ def build_extension(self, ext):
             "-DCMAKE_LIBRARY_OUTPUT_DIRECTORY=" + os.path.join(extdir, "impactx"),
             "-DCMAKE_VERBOSE_MAKEFILE=ON",
             "-DCMAKE_PYTHON_OUTPUT_DIRECTORY=" + extdir,
-            "-DPython_EXECUTABLE=" + sys.executable,
             ## variants
             "-DImpactX_COMPUTE=" + ImpactX_COMPUTE,
             "-DImpactX_FFT:BOOL=" + ImpactX_FFT,