1 error[E0004]: non-exhaustive patterns: type `()` is non-empty
2 --> $DIR/issue-3096-1.rs:2:11
7 = help: ensure that all possible cases are being handled, possibly by adding wildcards or more match arms
8 = note: the matched value is of type `()`
10 error: aborting due to previous error
12 For more information about this error, try `rustc --explain E0004`.