https://gcc.gnu.org/bugzilla/show_bug.cgi?id=90419
--- Comment #2 from Jim Wilson <wilson at gcc dot gnu.org> --- I talked to Palmer. Apparently what you want to do is build multilibs for lp64 and lp64d, to test the linux multilib support. That isn't currently supported. I would suggest applying a local patch to change the gcc/config/riscv/t-linux-multilib file with one that just has the lp64 and lp64d multilibs. If you are trying to do this natively, you are likely to run into problems along the way, as no one has tried to do this before as far as I know.
