Stabilize feature(iterator_fold_self): Iterator::reduce

compiler/rustc_ast/src/lib.rs

@@ -14,7 +14,6 @@
 #![feature(const_fn_transmute)]
 #![feature(const_panic)]
 #![feature(crate_visibility_modifier)]
-#![feature(iterator_fold_self)]
 #![feature(label_break_value)]
 #![feature(nll)]
 #![feature(or_patterns)]

compiler/rustc_hir/src/lib.rs

@@ -6,7 +6,6 @@
 #![feature(const_fn)] // For the unsizing cast on `&[]`
 #![feature(const_panic)]
 #![feature(in_band_lifetimes)]
-#![feature(iterator_fold_self)]
 #![feature(once_cell)]
 #![feature(or_patterns)]
 #![recursion_limit = "256"]

library/core/src/iter/traits/iterator.rs

@@ -2143,8 +2143,6 @@ pub trait Iterator {
     /// Find the maximum value:
     ///
     /// ```
-    /// #![feature(iterator_fold_self)]
-    ///
     /// fn find_max<I>(iter: I) -> Option<I::Item>
     ///     where I: Iterator,
     ///           I::Item: Ord,
@@ -2160,7 +2158,7 @@ pub trait Iterator {
     /// assert_eq!(find_max(b.iter()), None);
     /// ```
     #[inline]
-    #[unstable(feature = "iterator_fold_self", issue = "68125")]
+    #[stable(feature = "iterator_fold_self", since = "1.51.0")]
     fn reduce<F>(mut self, f: F) -> Option<Self::Item>
     where
         Self: Sized,