src/test/ui/macros/macro-in-expression-context-2.stderr

error: macro expansion ends with an incomplete expression: expected expression
  --> $DIR/macro-in-expression-context-2.rs:5:16
   |
LL | macro_rules! empty { () => () }
   |                            -- in this macro arm
...
LL |         _ => { empty!() }
   |                ^^^^^^^^ expected expression

error: aborting due to previous error