Segfault involving lazy and unhandled effect

[bobatkey]

The following program causes a segfault in the toplevel and the bytecode compiler:

effect Foo : bool
effect Bar : unit

let test = lazy (perform Foo)

let main () =
  Lazy.force test

let _ =
  match main () with
    | effect Bar k ->
       continue k ()
    | x -> x

[kayceesrk]

Fixed by 68f1be5ee31cc8d8fd40d2db404311592e47d19f.