ices/43037.rs: fixed with errors

[github-actions]

Issue: rust-lang/rust#43037

#![crate_type = "lib"]
#![feature(specialization)] // comment this line to get the expected behavior
trait X {}
trait Y: X {}
trait Z { type Assoc: Y; }
struct A<T>(T);

impl<T> Y for T where T: X {}
impl<T: X> Z for A<T> { type Assoc = T; }

// this impl is invalid, but causes an ICE anyway
impl<T> From<<A<T> as Z>::Assoc> for T {}

fn main() {}

=== stdout ===
=== stderr ===
warning: the feature `specialization` is incomplete and may not be safe to use and/or cause compiler crashes
 --> /home/runner/work/glacier/glacier/ices/43037.rs:2:12
  |
2 | #![feature(specialization)] // comment this line to get the expected behavior
  |            ^^^^^^^^^^^^^^
  |
  = note: `#[warn(incomplete_features)]` on by default
  = note: see issue #31844 <https://github.com/rust-lang/rust/issues/31844> for more information
  = help: consider using `min_specialization` instead, which is more stable and complete

error[E0210]: type parameter `T` must be used as the type parameter for some local type (e.g., `MyStruct<T>`)
  --> /home/runner/work/glacier/glacier/ices/43037.rs:12:6
   |
12 | impl<T> From<<A<T> as Z>::Assoc> for T {}
   |      ^ type parameter `T` must be used as the type parameter for some local type
   |
   = note: implementing a foreign trait is only possible if at least one of the types for which it is implemented is local
   = note: only traits defined in the current crate can be implemented for a type parameter

error: aborting due to previous error; 1 warning emitted

For more information about this error, try `rustc --explain E0210`.
==============