ref: bd49f398995ad7da3198d1a3d3309591dd23c9ee dir: /src/libc/arch/amd64/linux/_cerrno.s/
.file "_cerrno.s" .globl _cerrno _cerrno: cmpq $0,%rax js 1f retq 1: neg %rax mov %eax,(errno) mov $-1,%eax retq