let expected_return_type = if tcx.lang_items().termination().is_some() {
// we take the return type of the given main function, the real check is done
// in `check_fn`
let expected_return_type = if tcx.lang_items().termination().is_some() {
// we take the return type of the given main function, the real check is done
// in `check_fn`