error: irrefutable if-let guard
  --> $DIR/warns.rs:7:24
   |
LL |         Some(x) if let () = x => {}
   |                        ^^
   |
note: the lint level is defined here
  --> $DIR/warns.rs:4:8
   |
LL | #[deny(irrefutable_let_patterns)]
   |        ^^^^^^^^^^^^^^^^^^^^^^^^

error: unreachable pattern
  --> $DIR/warns.rs:16:25
   |
LL |         x if let None | None = x => {}
   |                         ^^^^
   |
note: the lint level is defined here
  --> $DIR/warns.rs:13:8
   |
LL | #[deny(unreachable_patterns)]
   |        ^^^^^^^^^^^^^^^^^^^^

error: aborting due to 2 previous errors