In file included from src/arch/riscv/payload.c:10: src/arch/riscv/include/mcall.h:57:46: error: register 'sp' unsuitable for global register variables on this target 57 | register uintptr_t current_stack_pointer asm("sp"); | ^ src/arch/riscv/payload.c:98:5: error: unknown register name 'a0' in asm 98 | : "a0", "a1"); | ^ 2 errors generated.