error[E0308]: mismatched types
  --> $DIR/never-assign-wrong-type.rs:7:16
   |
LL |     let x: ! = "hello";
   |            -   ^^^^^^^ expected `!`, found `&str`
   |            |
   |            expected due to this
   |
   = note:   expected type `!`
           found reference `&'static str`

error: aborting due to 1 previous error

For more information about this error, try `rustc --explain E0308`.