src/test/ui/fn/issue-80179.stderr

   1 error[E0121]: the placeholder `_` is not allowed within types on item signatures for return types
   2   --> $DIR/issue-80179.rs:10:24
   3    |
   4 LL | fn returns_fn_ptr() -> _ {
   5    |                        ^
   6    |                        |
   7    |                        not allowed in type signatures
   8    |                        help: replace with the correct return type: `fn() -> i32`
   9
  10 error[E0121]: the placeholder `_` is not allowed within types on item signatures for return types
  11   --> $DIR/issue-80179.rs:18:25
  12    |
  13 LL | fn returns_closure() -> _ {
  14    |                         ^ not allowed in type signatures
  15    |
  16    = help: consider using an `Fn`, `FnMut`, or `FnOnce` trait bound
  17    = note: for more information on `Fn` traits and closure types, see https://doc.rust-lang.org/book/ch13-01-closures.html
  18
  19 error: aborting due to 2 previous errors
  20
  21 For more information about this error, try `rustc --explain E0121`.