Unit-like structs in const generic arguments

[sanxiyn]

#![feature(const_generics)]

#[derive(PartialEq, Eq)]
struct Unit;
trait Const<const U: Unit> {}
impl Const<Unit> for () {} // wrong number of const arguments

Const<{Unit}> works. See also #66615.

[lcnr]

@rustbot claim

[lcnr]

@rustbot release-assignment

[varkor]

This isn't an issue for min_const_generics, because user-defined types may not be used as const generic types.