error[E0121]: the placeholder `_` is not allowed within types on item signatures for return types
  --> $DIR/E0121.rs:1:13
   |
LL | fn foo() -> _ { 5 }
   |             ^
   |             |
   |             not allowed in type signatures
   |             help: replace with the correct return type: `i32`

error[E0121]: the placeholder `_` is not allowed within types on item signatures for static variables
  --> $DIR/E0121.rs:3:13
   |
LL | static BAR: _ = "test";
   |             ^ not allowed in type signatures
   |
help: replace this with a fully-specified type
   |
LL - static BAR: _ = "test";
LL + static BAR: &str = "test";
   |

error: aborting due to 2 previous errors

For more information about this error, try `rustc --explain E0121`.