error: `dyn` is a keyword in the 2018 edition
  --> $DIR/dyn-keyword.rs:8:9
   |
LL |     let dyn = (); //~ ERROR dyn
   |         ^^^ help: you can use a raw identifier to stay compatible: `r#dyn`
   |
note: lint level defined here
  --> $DIR/dyn-keyword.rs:5:9
   |
LL | #![deny(keyword_idents)]
   |         ^^^^^^^^^^^^^^
   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in the 2018 edition!
   = note: for more information, see issue #49716 <https://github.com/rust-lang/rust/issues/49716>

error: aborting due to previous error