ref: 63ee97c65c38dfd6a8100e8386610b10cb2c0d77 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) ;;