I am trying to use multilib config on arm/arm64, it worked well and we can build it fine. however I noticed that gdb wasn't working (it would core dump), and it turns out that this is python3 which is not working: 

root@dragonboard-410c:~# python3
Could not find platform independent libraries <prefix>
Could not find platform dependent libraries <exec_prefix>
Consider setting $PYTHONHOME to <prefix>[:<exec_prefix>]
Fatal Python error: Py_Initialize: Unable to get the locale encoding
ImportError: No module named 'encodings'

Current thread 0x0000007f8d53afe0 (most recent call first):
Aborted (core dumped)

I haven't tried on x86/x86_64, but given the error signature I am tempted to believe this is not something related to arm multilib.