Add 83919

Issue: rust-lang/rust#83919

ices/83919.rs

@@ -0,0 +1,26 @@
+#![feature(min_type_alias_impl_trait)]
+
+use std::future::Future;
+
+trait Foo {
+	type T;
+	type Fut2: Future<Output=Self::T>; // ICE gets triggered with traits other than Future here
+	type Fut: Future<Output=Self::Fut2>;
+	fn get_fut(&self) -> Self::Fut;
+}
+
+struct Implementor;
+
+impl Foo for Implementor {
+	type T = u64;
+	type Fut2 = impl Future<Output=u64>;
+	type Fut = impl Future<Output=Self::Fut2>;
+
+	fn get_fut(&self) -> Self::Fut {
+		async move {
+			42
+			// 42 does not impl Future and rustc does actually point out the error, but rustc also panics.
+			// Putting a valid Future here works fine.
+		}
+	}
+}