Adjust MaybeUninit feature names to avoid changing unstable one

Author: dtolnay

library/core/src/lib.rs

@@ -118,7 +118,7 @@
 #![feature(const_intrinsic_forget)]
 #![feature(const_likely)]
 #![feature(const_maybe_uninit_as_mut_ptr)]
-#![feature(const_maybe_uninit_assume_init_mut)]
+#![feature(const_maybe_uninit_assume_init)]
 #![feature(const_num_from_num)]
 #![feature(const_ops)]
 #![feature(const_option)]

library/core/src/mem/maybe_uninit.rs

@@ -622,7 +622,7 @@ impl<T> MaybeUninit<T> {
     /// // `x` had not been initialized yet, so this last line caused undefined behavior. ⚠️
     /// ```
     #[stable(feature = "maybe_uninit", since = "1.36.0")]
-    #[rustc_const_stable(feature = "const_maybe_uninit_assume_init", since = "1.59.0")]
+    #[rustc_const_stable(feature = "const_maybe_uninit_assume_init_by_value", since = "1.59.0")]
     #[inline(always)]
     #[rustc_diagnostic_item = "assume_init"]
     #[track_caller]
@@ -788,7 +788,7 @@ impl<T> MaybeUninit<T> {
     /// }
     /// ```
     #[stable(feature = "maybe_uninit_ref", since = "1.55.0")]
-    #[rustc_const_stable(feature = "const_maybe_uninit_assume_init", since = "1.59.0")]
+    #[rustc_const_stable(feature = "const_maybe_uninit_assume_init_ref", since = "1.59.0")]
     #[inline(always)]
     pub const unsafe fn assume_init_ref(&self) -> &T {
         // SAFETY: the caller must guarantee that `self` is initialized.
@@ -905,7 +905,7 @@ impl<T> MaybeUninit<T> {
     /// };
     /// ```
     #[stable(feature = "maybe_uninit_ref", since = "1.55.0")]
-    #[rustc_const_unstable(feature = "const_maybe_uninit_assume_init_mut", issue = "none")]
+    #[rustc_const_unstable(feature = "const_maybe_uninit_assume_init", issue = "none")]
     #[inline(always)]
     pub const unsafe fn assume_init_mut(&mut self) -> &mut T {
         // SAFETY: the caller must guarantee that `self` is initialized.
@@ -991,7 +991,7 @@ impl<T> MaybeUninit<T> {
     ///
     /// [`assume_init_mut`]: MaybeUninit::assume_init_mut
     #[unstable(feature = "maybe_uninit_slice", issue = "63569")]
-    #[rustc_const_unstable(feature = "const_maybe_uninit_assume_init_mut", issue = "none")]
+    #[rustc_const_unstable(feature = "const_maybe_uninit_assume_init", issue = "none")]
     #[inline(always)]
     pub const unsafe fn slice_assume_init_mut(slice: &mut [Self]) -> &mut [T] {
         // SAFETY: similar to safety notes for `slice_get_ref`, but we have a