ref: d52fd3b32109f12e529a7f5e380c5ee8f06aefcf dir: /lib/std/sjlj+x64.myr/
pkg std = type jmpbuf = struct regs : uint64[9] ;; extern const setjmp : (jb : jmpbuf# -> bool) extern const longjmp : (jb : jmpbuf# -> void) ;;