ices/68532.rs: fixed with no errors

[github-actions]

Issue: rust-lang/rust#68532

struct A<'a>(&'a ());

impl<'a> A<'a> {
    const N: usize = 68;

    fn foo(&self) {
        let mut b = [0; Self::N];
    }
}

fn main() {}

=== stdout ===
=== stderr ===
warning: unused variable: `b`
 --> /home/runner/work/glacier/glacier/ices/68532.rs:7:13
  |
7 |         let mut b = [0; Self::N];
  |             ^^^^^ help: if this is intentional, prefix it with an underscore: `_b`
  |
  = note: `#[warn(unused_variables)]` on by default

warning: variable does not need to be mutable
 --> /home/runner/work/glacier/glacier/ices/68532.rs:7:13
  |
7 |         let mut b = [0; Self::N];
  |             ----^
  |             |
  |             help: remove this `mut`
  |
  = note: `#[warn(unused_mut)]` on by default

warning: struct is never constructed: `A`
 --> /home/runner/work/glacier/glacier/ices/68532.rs:1:8
  |
1 | struct A<'a>(&'a ());
  |        ^
  |
  = note: `#[warn(dead_code)]` on by default

warning: associated constant is never used: `N`
 --> /home/runner/work/glacier/glacier/ices/68532.rs:4:5
  |
4 |     const N: usize = 68;
  |     ^^^^^^^^^^^^^^^^^^^^

warning: associated function is never used: `foo`
 --> /home/runner/work/glacier/glacier/ices/68532.rs:6:8
  |
6 |     fn foo(&self) {
  |        ^^^

warning: 5 warnings emitted

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

[JohnTitor]

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