llvm dev - Dec 2020 - Cannot compile code in arm64 machine

Hello;

I am trying to compile fortran code in a arm64 machine.  I built LLVM
using the -DLLVM_TARGETS_TO_BUILD="ARM;X86;AArch64" option.  But when
I type:

flang --target=arm64 appft.f -o appft

I get the following error:

clang-10: error: unknown argument: '-fc1'
clang-10: error: unknown argument: '-triple'
clang-10: error: no such file or directory: 'aarch64'


Can you please tell me how to resolve this?

Thank you very much