ref: cf57ad51e7ae7744b8a723f6d5fe6d67ca7c509c dir: /lib/std/sjlj.myr/
pkg std = type jmpbuf = struct regs : uint64[8] ;; extern const setjmp : (jb : jmpbuf# -> bool) extern const longjmp : (jb : jmpbuf# -> void) ;;