error[E0308]: mismatched types --> $DIR/issue-84128.rs:13:13 | LL | Foo(()) | --- ^^ expected integer, found `()` | | | arguments to this struct are incorrect | help: the type constructed contains `()` due to the type of the argument passed --> $DIR/issue-84128.rs:13:9 | LL | Foo(()) | ^^^^--^ | | | this argument influences the type of `Foo` note: tuple struct defined here --> $DIR/issue-84128.rs:5:8 | LL | struct Foo(T); | ^^^ error: aborting due to 1 previous error For more information about this error, try `rustc --explain E0308`.