ices/83993.rs: fixed with errors

[github-actions]

Issue: rust-lang/rust#83993

#![feature(generic_const_exprs)]
fn bug<'a>()
where
    for<'b> [(); {
        let x: &'b ();
        0
    }]:
{}

=== stdout ===
=== stderr ===
warning: the feature `generic_const_exprs` is incomplete and may not be safe to use and/or cause compiler crashes
 --> /home/runner/work/glacier/glacier/ices/83993.rs:1:12
  |
1 | #![feature(generic_const_exprs)]
  |            ^^^^^^^^^^^^^^^^^^^
  |
  = note: `#[warn(incomplete_features)]` on by default
  = note: see issue #76560 <https://github.com/rust-lang/rust/issues/76560> for more information

error[E0601]: `main` function not found in crate `83993`
 --> /home/runner/work/glacier/glacier/ices/83993.rs:8:3
  |
8 | {}
  |   ^ consider adding a `main` function to `/home/runner/work/glacier/glacier/ices/83993.rs`

error: aborting due to previous error; 1 warning emitted

For more information about this error, try `rustc --explain E0601`.
==============