ref: fc836572b87f619ac93eba9cc6f7ede657e4d17a 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) ;;