stabilize const_swap

Author: RalfJung

core/src/intrinsics/mod.rs

@@ -3983,7 +3983,8 @@ pub const fn is_val_statically_known<T: Copy>(_arg: T) -> bool {
 #[inline]
 #[rustc_intrinsic]
 // Const-unstable because `swap_nonoverlapping` is const-unstable.
-#[rustc_const_unstable(feature = "const_typed_swap", issue = "none")]
+#[rustc_intrinsic_const_stable_indirect]
+#[rustc_allow_const_fn_unstable(const_swap_nonoverlapping)] // this is anyway not called since CTFE implements the intrinsic
 pub const unsafe fn typed_swap<T>(x: *mut T, y: *mut T) {
     // SAFETY: The caller provided single non-overlapping items behind
     // pointers, so swapping them with `count: 1` is fine.

core/src/lib.rs

@@ -112,7 +112,6 @@
 #![feature(asm_experimental_arch)]
 #![feature(const_carrying_mul_add)]
 #![feature(const_eval_select)]
-#![feature(const_typed_swap)]
 #![feature(core_intrinsics)]
 #![feature(coverage_attribute)]
 #![feature(internal_impls_macro)]

core/src/mem/mod.rs

@@ -725,7 +725,7 @@ pub unsafe fn uninitialized<T>() -> T {
 /// ```
 #[inline]
 #[stable(feature = "rust1", since = "1.0.0")]
-#[rustc_const_unstable(feature = "const_swap", issue = "83163")]
+#[rustc_const_stable(feature = "const_swap", since = "CURRENT_RUSTC_VERSION")]
 #[rustc_diagnostic_item = "mem_swap"]
 pub const fn swap<T>(x: &mut T, y: &mut T) {
     // SAFETY: `&mut` guarantees these are typed readable and writable

core/src/ptr/mod.rs

@@ -1009,9 +1009,8 @@ pub const fn slice_from_raw_parts_mut<T>(data: *mut T, len: usize) -> *mut [T] {
 /// ```
 #[inline]
 #[stable(feature = "rust1", since = "1.0.0")]
-#[rustc_const_unstable(feature = "const_swap", issue = "83163")]
+#[rustc_const_stable(feature = "const_swap", since = "CURRENT_RUSTC_VERSION")]
 #[rustc_diagnostic_item = "ptr_swap"]
-#[rustc_const_stable_indirect]
 pub const unsafe fn swap<T>(x: *mut T, y: *mut T) {
     // Give ourselves some scratch space to work with.
     // We do not have to worry about drops: `MaybeUninit` does nothing when dropped.

core/src/ptr/mut_ptr.rs

@@ -1594,7 +1594,7 @@ impl<T: ?Sized> *mut T {
     ///
     /// [`ptr::swap`]: crate::ptr::swap()
     #[stable(feature = "pointer_methods", since = "1.26.0")]
-    #[rustc_const_unstable(feature = "const_swap", issue = "83163")]
+    #[rustc_const_stable(feature = "const_swap", since = "CURRENT_RUSTC_VERSION")]
     #[inline(always)]
     pub const unsafe fn swap(self, with: *mut T)
     where

core/src/ptr/non_null.rs

@@ -1146,7 +1146,7 @@ impl<T: ?Sized> NonNull<T> {
     /// [`ptr::swap`]: crate::ptr::swap()
     #[inline(always)]
     #[stable(feature = "non_null_convenience", since = "1.80.0")]
-    #[rustc_const_unstable(feature = "const_swap", issue = "83163")]
+    #[rustc_const_stable(feature = "const_swap", since = "CURRENT_RUSTC_VERSION")]
     pub const unsafe fn swap(self, with: NonNull<T>)
     where
         T: Sized,

core/src/slice/mod.rs

@@ -913,7 +913,7 @@ impl<T> [T] {
     /// assert!(v == ["a", "b", "e", "d", "c"]);
     /// ```
     #[stable(feature = "rust1", since = "1.0.0")]
-    #[rustc_const_unstable(feature = "const_swap", issue = "83163")]
+    #[rustc_const_stable(feature = "const_swap", since = "CURRENT_RUSTC_VERSION")]
     #[inline]
     #[track_caller]
     pub const fn swap(&mut self, a: usize, b: usize) {

core/tests/lib.rs

@@ -15,7 +15,6 @@
 #![feature(clone_to_uninit)]
 #![feature(const_black_box)]
 #![feature(const_eval_select)]
-#![feature(const_swap)]
 #![feature(const_swap_nonoverlapping)]
 #![feature(const_trait_impl)]
 #![feature(core_intrinsics)]