title: The file has not the right magic number
body: <p>I have a bytecode, which worked previously well. Today, I'm trying to run it, I get an error <code>the file './analyze' has not the right magic number: expected Caml1999X029, got Caml1999X023</code>.</p>
  <p>I try to switch OCaml version from <code>4.12.0</code> e.g., to <code>4.07.0</code> which might be the version when I built the bytecode. I still get the same error when running the bytecode.</p>
  <p>Does anyone know how I could run this bytecode correctly?</p>