It seems useful, I've backported to GCC 9/10/11. Without this patch: $ riscv64-unknown-elf-gcc -march=rv32imafd ~/hello.c -march=rv64gc /scratch1/kitoc/riscv-gnu-workspace/rv64gc/install/bin/../lib/gcc/riscv64-unknown-elf/11.1.0/../../../../riscv64-unknown-elf/bin/ld: unrecognised emulation mode: elf3264lriscv Supported emulations: elf64lriscv elf32lriscv elf64briscv elf32briscv collect2: error: ld returned 1 exit status
With this patch: $ riscv64-unknown-elf-gcc -march=rv32imafd ~/hello.c -march=rv64gc // No error! On Fri, Apr 30, 2021 at 11:42 AM Jim Wilson <j...@sifive.com> wrote: > > On Wed, Apr 28, 2021 at 1:30 AM Geng Qi via Gcc-patches < > gcc-patches@gcc.gnu.org> wrote: > > > gcc/ChangeLog: > > * config/riscv/riscv.opt (march=,mabi=): Negative itself. > > > > Thanks. I committed this. > > Do we need to backport to release branches? This looks like an uncommon > problem, or we would have noticed this before. > > Jim