Remove the default type of Rem::Output

src/libcore/lib.rs

@@ -69,7 +69,6 @@
 #![feature(allow_internal_unstable)]
 #![feature(arbitrary_self_types)]
 #![feature(asm)]
-#![feature(associated_type_defaults)]
 #![feature(bound_cloned)]
 #![feature(cfg_target_has_atomic)]
 #![feature(concat_idents)]

src/libcore/ops/arith.rs

@@ -508,7 +508,7 @@ fn div(self, other: $t) -> $t { self / other }
 pub trait Rem<Rhs=Self> {
     /// The resulting type after applying the `%` operator.
     #[stable(feature = "rust1", since = "1.0.0")]
-    type Output = Self;
+    type Output;
 
     /// Performs the `%` operation.
     #[must_use]