error[E0308]: mismatched types --> $DIR/issue-84128.rs:13:13 | LL | Foo(()) | --- ^^ expected integer, found `()` | | | arguments to this struct are incorrect | note: return type inferred to be `{integer}` here --> $DIR/issue-84128.rs:10:20 | LL | return Foo(0); | ^^^^^^ note: tuple struct defined here --> $DIR/issue-84128.rs:5:8 | LL | struct Foo(T); | ^^^ error: aborting due to previous error For more information about this error, try `rustc --explain E0308`.