CMake find_package(PythonInterp 3.7 REQUIRED) for Win32 platform

Question

I have some project which supposed to support Win32 and x64 platform. Some code is generated by python script. This script uses python3 features.

In CMakeLists.txt I have something like this:

find_package(PythonInterp REQUIRED)
if (CMAKE_CL_64)
    set(MY_APP_PLATFORM "x64")
else()
    set(MY_APP_PLATFORM "Win32")
endif()

add_custom_command(TARGET MyApp
    PRE_BUILD
    COMMAND ${PYTHON_EXECUTABLE} ${MyApp_ROOT}/generator.py -p ${MY_APP_PLATFORM }
    WORKING_DIRECTORY ${PATH_GENERATED_SRC}
    COMMENT "Generating code..."
    VERBATIM
)

Quite simple.

Now when project for x64 is used everything works like a charm, but when building for Win32 (cmake have to generate separate project) cmake finds python 2.7.2 .

Changing CMakeLists.txt this way:

find_package(PythonInterp 3.7 REQUIRED)

Leads to cmake failure.

Is there way to fix it, or do I have to correct pythons script to be python2 compatible?

Or do I have to install python3 for 32 and 64 bits to cover both platforms?

Answer 1

The CMake Module is FindPython3.cmake in your cmake distribution.

This should work:

find_package(Python3 COMPONENTS Interpreter)

add_custom_command(TARGET MyApp
    PRE_BUILD
    COMMAND ${PYTHON3_EXECUTABLE} ${MyApp_ROOT}/generator.py -p ${MY_APP_PLATFORM}
    WORKING_DIRECTORY ${PATH_GENERATED_SRC}
    COMMENT "Generating code..."
    VERBATIM
)

It is available since cmake 3.12 .

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