error[E0423]: expected value, found struct `X`
  --> $DIR/issue-61226.rs:4:18
   |
LL | struct X {}
   | ----------- `X` defined here
LL | fn main() {
LL |     let _ = vec![X]; //…
   |                  ^ help: use struct literal syntax instead: `X {}`

error: aborting due to 1 previous error

For more information about this error, try `rustc --explain E0423`.