error[E0004]: non-exhaustive patterns: type `std::option::Option<i32>` is non-empty
  --> $DIR/E0004-2.rs:4:11
   |
LL |     match x { } //~ ERROR E0004
   |           ^
   |
help: ensure that all possible cases are being handled, possibly by adding wildcards or more match arms
  --> $DIR/E0004-2.rs:4:11
   |
LL |     match x { } //~ ERROR E0004
   |           ^

error: aborting due to previous error

For more information about this error, try `rustc --explain E0004`.