compile ASM using armasm with MSYS2 in windows10

I used the cmake + ninja and got the rule for compiling ASM file
command = \armasm.exe @$RSP_FILE -o $out $in
description = Building ASM object $out
rspfile = $RSP_FILE
rspfile_content = $DEFINES $INCLUDES $FLAGS

but the @ is not recognised by armasm.exe, and I checked the cmake code.
I found the CMAKE_${lang}_RESPONSE_FILE_LINK_FLAG for ASM is not be set in ARMCC-ASM.cmak.

Why is it?

I don’t know if that compiler is supported yet (I don’t see any armasm search logic at least). We’ll probably need to add support for it.

Could you please file an issue? Thanks.

Cc: @brad.king