ices/86756.rs: fixed with errors

=== stdout ===
=== stderr ===
error[E0403]: the name `T` is already used for a generic parameter in this item's generic parameters
 --> /home/runner/work/glacier/glacier/ices/86756.rs:1:14
  |
1 | trait Foo<T, T = T> {}
  |           -  ^ already used
  |           |
  |           first use of `T`

warning: trait objects without an explicit `dyn` are deprecated
 --> /home/runner/work/glacier/glacier/ices/86756.rs:3:15
  |
3 |     eq::<dyn, Foo>
  |               ^^^ help: use `dyn`: `dyn Foo`
  |
  = note: `#[warn(bare_trait_objects)]` on by default
  = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
  = note: for more information, see issue #80165 <rust-lang/rust#80165>

error[E0601]: `main` function not found in crate `86756`
 --> /home/runner/work/glacier/glacier/ices/86756.rs:1:1
  |
1 | / trait Foo<T, T = T> {}
2 | | fn eq<A, B>() {
3 | |     eq::<dyn, Foo>
4 | | }
  | |_^ consider adding a `main` function to `/home/runner/work/glacier/glacier/ices/86756.rs`

error[E0224]: at least one trait is required for an object type
 --> /home/runner/work/glacier/glacier/ices/86756.rs:3:10
  |
3 |     eq::<dyn, Foo>
  |          ^^^

error[E0107]: missing generics for trait `Foo`
 --> /home/runner/work/glacier/glacier/ices/86756.rs:3:15
  |
3 |     eq::<dyn, Foo>
  |               ^^^ expected at least 1 generic argument
  |
note: trait defined here, with at least 1 generic parameter: `T`
 --> /home/runner/work/glacier/glacier/ices/86756.rs:1:7
  |
1 | trait Foo<T, T = T> {}
  |       ^^^ -
help: add missing generic argument
  |
3 |     eq::<dyn, Foo<T>>
  |               ^^^^^^

error: aborting due to 4 previous errors; 1 warning emitted

Some errors have detailed explanations: E0107, E0224, E0403, E0601.
For more information about an error, try `rustc --explain E0107`.
==============