#3989 raises the issue that `@Subscribe` methods with primitive parameter types can be registered but they will never be called because the `post()` method takes `Object` and so autoboxes primitives.

`EventBus` should throw an exception preventing registering any `@Subscribe` methods with primitive parameters and document the restriction.
private List<DeadEvent> events = Lists.newArrayList();
    @Subscribe
    public void ohNoesIHaveDied(DeadEvent event) {
      events.add(event);
    }
    public List<DeadEvent> getEvents() {
      return events;
    }
  }
  private interface Callback<T> {
    void call(T t);
  }
}