Failed when USE_LIB64=ON

[GeorgeDonald]

I got the following errors if I use -DUSE_LIB64=ON for the first time:

[100%] Relocate _sysconfigdata__linux2_.py and update pybuilddir.txt
Could not find platform independent libraries <prefix>
Could not find platform dependent libraries <exec_prefix>
Consider setting $PYTHONHOME to <prefix>[:<exec_prefix>]
Python path configuration:
  PYTHONHOME = (not set)
  PYTHONPATH = (not set)
  program name = '/home/gdong/python/build/bin/python'
  isolated = 0
  environment = 0
  user site = 1
  import site = 0
  sys._base_executable = '/home/gdong/python/build/bin/python'
  sys.base_prefix = '/home/gdong/python/install'
  sys.base_exec_prefix = '/home/gdong/python/install'
  sys.platlibdir = 'lib'
  sys.executable = '/home/gdong/python/build/bin/python'
  sys.prefix = '/home/gdong/python/install'
  sys.exec_prefix = '/home/gdong/python/install'
  sys.path = [
    '/home/gdong/python/install/lib/python39.zip',
    '/home/gdong/python/install/lib/python3.9',
    '/home/gdong/python/install/lib/python3.9/lib-dynload',
    '/home/gdong/python/install/lib/python3.9/plat-linux2',
    '/home/gdong/python/install/lib/python3.9/lib-tk',
    '/home/gdong/python/install/lib/lib-dynload',
  ]
Fatal Python error: init_fs_encoding: failed to get the Python codec of the filesystem encoding
Python runtime state: core initialized
ModuleNotFoundError: No module named 'encodings'

Current thread 0x00007f222dc73740 (most recent call first):
<no Python frame>
make[2]: *** [bin/pybuilddir.txt] Error 1
make[1]: *** [CMakeBuild/python/CMakeFiles/update_sysconfig.dir/all] Error 2
make: *** [all] Error 2

It seems like it still set sys.paths to lib instead of lib64.

This could be resolved by setting -DUSE_LIB64=OFF first to make it and then set it to ON and rebuild it.

[jcfr]

Thanks for the report 🙏

I was able to reproduce on Ubuntu 20.04 doing:

cmake \
  -DUSE_LIB64:BOOL=ON \
  -S python-cmake-buildsystem \
  -B python-cmake-buildsystem-build-test

cmake \
 --build python-cmake-buildsystem-build-test \
 --parallel 8

Is it something you could help address ?