https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109713
--- Comment #2 from Martin Liška <marxin at gcc dot gnu.org> --- So something like this can fix it: diff --git a/gcc/config/riscv/sync.md b/gcc/config/riscv/sync.md index ba132d8a1ce..206adcfec3c 100644 --- a/gcc/config/riscv/sync.md +++ b/gcc/config/riscv/sync.md @@ -61,6 +61,8 @@ (define_insn "mem_thread_fence_1" return "fence\tr,rw"; else if (model == MEMMODEL_RELEASE) return "fence\trw,w"; + else + gcc_unreachable (); } [(set (attr "length") (const_int 4))])