ices/68205.rs: fixed with errors

[github-actions]

Issue: rust-lang/rust#68205

#![allow(unused)]
#![feature(const_generics)]

trait Child {
    const N: usize;
}

struct C1;
impl Child for C1 {
    const N: usize = 2;
}

struct Main<C: Child> {
    c: C
}

impl<C: Child> Main<C> {
    fn test() -> [u8; C::N] {
        [0; C::N]
    }
}

// Doesn't crash without `fn main()` or `#![crate_type = "lib"]`
fn main() {}

=== stdout ===
=== stderr ===
warning: the feature `const_generics` is incomplete and may cause the compiler to crash
 --> /home/runner/work/glacier/glacier/ices/68205.rs:2:12
  |
2 | #![feature(const_generics)]
  |            ^^^^^^^^^^^^^^
  |
  = note: `#[warn(incomplete_features)]` on by default

error: constant expression depends on a generic parameter
  --> /home/runner/work/glacier/glacier/ices/68205.rs:18:5
   |
18 | /     fn test() -> [u8; C::N] {
19 | |         [0; C::N]
20 | |     }
   | |_____^
   |
   = note: this may fail depending on what value the parameter takes

error: aborting due to previous error

==============