#![feature(default_field_values)] #[derive(Default)] #[non_exhaustive] //~ ERROR `#[non_exhaustive]` can't be used to annotate items with default field values struct Foo { x: i32 = 42 + 3, } #[derive(Default)] enum Bar { #[non_exhaustive] #[default] Baz { //~ ERROR default variant must be exhaustive x: i32 = 42 + 3, } } fn main () {}