theemathas · Sep 25, 2026
diff --git a/library/alloc/src/lib.rs b/library/alloc/src/lib.rs
@@ -143,7 +143,6 @@
 #![feature(io_const_error)]
 #![feature(io_const_error_internals)]
 #![feature(io_slice_as_bytes)]
-#![feature(iter_advance_by)]
 #![feature(iter_next_chunk)]
 #![feature(legacy_receiver_trait)]
 #![feature(likely_unlikely)]

diff --git a/library/alloctests/lib.rs b/library/alloctests/lib.rs
@@ -32,7 +32,6 @@
 #![feature(extend_one_unchecked)]
 #![feature(hasher_prefixfree_extras)]
 #![feature(inplace_iteration)]
-#![feature(iter_advance_by)]
 #![feature(iter_next_chunk)]
 #![feature(maybe_uninit_uninit_array_transpose)]
 #![feature(ptr_alignment_type)]

diff --git a/library/alloctests/tests/lib.rs b/library/alloctests/tests/lib.rs
@@ -29,7 +29,6 @@
 #![feature(hashmap_internals)]
 #![feature(inplace_iteration)]
 #![feature(io_const_error)]
-#![feature(iter_advance_by)]
 #![feature(iter_array_chunks)]
 #![feature(iter_next_chunk)]
 #![feature(linked_list_cursors)]

diff --git a/library/core/src/iter/traits/double_ended.rs b/library/core/src/iter/traits/double_ended.rs
@@ -168,8 +168,6 @@ pub const trait DoubleEndedIterator: [const] Iterator {
     /// Basic usage:
     ///
     /// ```
-    /// #![feature(iter_advance_by)]
-    ///
     /// use std::num::NonZero;
     ///
     /// let a = [3, 4, 5, 6];
@@ -184,7 +182,7 @@ pub const trait DoubleEndedIterator: [const] Iterator {
     /// [`Ok(())`]: Ok
     /// [`Err(k)`]: Err
     #[inline]
-    #[unstable(feature = "iter_advance_by", issue = "77404")]
+    #[stable(feature = "iter_advance_by", since = "CURRENT_RUSTC_VERSION")]
     fn advance_back_by(&mut self, n: usize) -> Result<(), NonZero<usize>>
     where
         Self::Item: [const] Destruct,

diff --git a/library/core/src/iter/traits/iterator.rs b/library/core/src/iter/traits/iterator.rs
@@ -292,8 +292,6 @@ pub const trait Iterator {
     /// # Examples
     ///
     /// ```
-    /// #![feature(iter_advance_by)]
-    ///
     /// use std::num::NonZero;
     ///
     /// let a = [1, 2, 3, 4];
@@ -305,7 +303,7 @@ pub const trait Iterator {
     /// assert_eq!(iter.advance_by(100), Err(NonZero::new(99).unwrap())); // only `4` was skipped
     /// ```
     #[inline]
-    #[unstable(feature = "iter_advance_by", issue = "77404")]
+    #[stable(feature = "iter_advance_by", since = "CURRENT_RUSTC_VERSION")]
     fn advance_by(&mut self, n: usize) -> Result<(), NonZero<usize>>
     where
         Self::Item: [const] Destruct,

diff --git a/library/coretests/benches/lib.rs b/library/coretests/benches/lib.rs
@@ -7,7 +7,6 @@
 #![feature(trusted_random_access)]
 #![feature(iter_array_chunks)]
 #![feature(iter_next_chunk)]
-#![feature(iter_advance_by)]
 #![feature(num_internals)]
 #![feature(uint_gather_scatter_bits)]
 #![allow(internal_features)]

diff --git a/library/coretests/tests/lib.rs b/library/coretests/tests/lib.rs
@@ -76,7 +76,6 @@
 #![feature(io_slice_as_bytes)]
 #![feature(ip)]
 #![feature(is_ascii_octdigit)]
-#![feature(iter_advance_by)]
 #![feature(iter_array_chunks)]
 #![feature(iter_collect_into)]
 #![feature(iter_intersperse)]

diff --git a/library/std/src/lib.rs b/library/std/src/lib.rs
@@ -363,7 +363,6 @@
 #![feature(io_error_uncategorized)]
 #![feature(io_slice_as_bytes)]
 #![feature(ip)]
-#![feature(iter_advance_by)]
 #![feature(iter_next_chunk)]
 #![feature(maybe_dangling)]
 #![feature(maybe_uninit_array_assume_init)]

diff --git a/src/tools/miri/src/lib.rs b/src/tools/miri/src/lib.rs
@@ -1,4 +1,4 @@
-#![cfg_attr(all(feature = "native-lib", unix), feature(iter_advance_by))]
+#![cfg_attr(all(feature = "native-lib", unix, bootstrap), feature(iter_advance_by))]
 #![cfg_attr(
     all(
         feature = "native-lib",

diff --git a/src/tools/miri/tests/pass/vec.rs b/src/tools/miri/tests/pass/vec.rs
@@ -2,7 +2,7 @@
 //@compile-flags: -Zmiri-strict-provenance
 //@[tree_implicit_writes]compile-flags: -Zmiri-tree-borrows -Zmiri-tree-borrows-implicit-writes
 //@[tree]compile-flags: -Zmiri-tree-borrows
-#![feature(iter_advance_by, iter_next_chunk)]
+#![feature(iter_next_chunk)]
 
 // Gather all references from a mutable iterator and make sure Miri notices if
 // using them is dangerous.

diff --git a/tests/ui/delegation/generics/def-path-hash-collision-ice-153410.rs b/tests/ui/delegation/generics/def-path-hash-collision-ice-153410.rs
@@ -1,7 +1,7 @@
 //@ compile-flags: -Z deduplicate-diagnostics=yes
 //@ edition:2024
 
-#![feature(fn_delegation)]#![feature(iter_advance_by)]
+#![feature(fn_delegation)]
 #![feature(iter_array_chunks)]
 #![feature(iterator_try_collect)]
 #![feature(iterator_try_reduce)]

diff --git a/tests/ui/delegation/generics/synth-params-ice-143498.rs b/tests/ui/delegation/generics/synth-params-ice-143498.rs
@@ -2,7 +2,6 @@
 //@ edition:2024
 
 #![feature(fn_delegation)]
-#![feature(iter_advance_by)]
 #![feature(iter_array_chunks)]
 #![feature(iterator_try_collect)]
 #![feature(iterator_try_reduce)]

diff --git a/tests/ui/delegation/generics/synth-params-ice-143498.stderr b/tests/ui/delegation/generics/synth-params-ice-143498.stderr
@@ -1,19 +1,19 @@
 error[E0425]: cannot find type `X` in this scope
-  --> $DIR/synth-params-ice-143498.rs:19:6
+  --> $DIR/synth-params-ice-143498.rs:18:6
    |
 LL | impl X {
    |      ^ not found in this scope
 
 error[E0575]: cannot find method or associated constant `Item` in trait `Iterator`
-  --> $DIR/synth-params-ice-143498.rs:21:43
+  --> $DIR/synth-params-ice-143498.rs:20:43
    |
 LL |     reuse< std::fmt::Debug as Iterator >::*;
    |                                           ^ not found in `Iterator`
    |
    = note: an associated type named `Iterator::Item` exists in another namespace
 
 error[E0782]: expected a type, found a trait
-  --> $DIR/synth-params-ice-143498.rs:21:12
+  --> $DIR/synth-params-ice-143498.rs:20:12
    |
 LL |     reuse< std::fmt::Debug as Iterator >::*;
    |            ^^^^^^^^^^^^^^^