error: useless lint attribute
 --> $DIR/useless_attribute.rs:5:1
  |
5 | #[allow(dead_code)] //~ ERROR useless lint attribute
  | ^^^^^^^^^^^^^^^^^^^
  |
note: lint level defined here
 --> $DIR/useless_attribute.rs:3:9
  |
3 | #![deny(useless_attribute)]
  |         ^^^^^^^^^^^^^^^^^
help: if you just forgot a `!`, use
  | #![allow(dead_code)] //~ ERROR useless lint attribute

error: aborting due to previous error