ref: 1f99d2dc0f2e8afe604bfe777063b4f2e277e185 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) ;;