error[E0277]: the trait bound `E: From<()>` is not satisfied
  --> $DIR/never-value-fallback-issue-66757.rs:28:6
   |
LL |     <E as From<_>>::from(never);
   |      ^ the trait `From<()>` is not implemented for `E`
   |
   = help: the trait `From<!>` is implemented for `E`
   = help: for that trait implementation, expected `!`, found `()`

error: aborting due to 1 previous error

For more information about this error, try `rustc --explain E0277`.