Auto merge of rust-lang#134768 - RalfJung:const_alloc_layout, r=jhpratt

stabilize const_alloc_layout

libs-api FCP passed in rust-lang#67521

Fixes rust-lang#67521

library/core/src/alloc/layout.rs

@@ -178,8 +178,7 @@ impl Layout {
     /// allocate backing structure for `T` (which could be a trait
     /// or other unsized type like a slice).
     #[stable(feature = "alloc_layout", since = "1.28.0")]
-    #[rustc_const_unstable(feature = "const_alloc_layout", issue = "67521")]
-    #[rustc_const_stable_indirect]
+    #[rustc_const_stable(feature = "const_alloc_layout", since = "CURRENT_RUSTC_VERSION")]
     #[must_use]
     #[inline]
     pub const fn for_value<T: ?Sized>(t: &T) -> Self {
@@ -253,8 +252,7 @@ impl Layout {
     /// Returns an error if the combination of `self.size()` and the given
     /// `align` violates the conditions listed in [`Layout::from_size_align`].
     #[stable(feature = "alloc_layout_manipulation", since = "1.44.0")]
-    #[rustc_const_unstable(feature = "const_alloc_layout", issue = "67521")]
-    #[rustc_const_stable_indirect]
+    #[rustc_const_stable(feature = "const_alloc_layout", since = "CURRENT_RUSTC_VERSION")]
     #[inline]
     pub const fn align_to(&self, align: usize) -> Result<Self, LayoutError> {
         if let Some(align) = Alignment::new(align) {
@@ -329,8 +327,7 @@ impl Layout {
     /// This is equivalent to adding the result of `padding_needed_for`
     /// to the layout's current size.
     #[stable(feature = "alloc_layout_manipulation", since = "1.44.0")]
-    #[rustc_const_unstable(feature = "const_alloc_layout", issue = "67521")]
-    #[rustc_const_stable_indirect]
+    #[rustc_const_stable(feature = "const_alloc_layout", since = "CURRENT_RUSTC_VERSION")]
     #[must_use = "this returns a new `Layout`, \
                   without modifying the original"]
     #[inline]
@@ -429,8 +426,7 @@ impl Layout {
     /// # assert_eq!(repr_c(&[u64, u32, u16, u32]), Ok((s, vec![0, 8, 12, 16])));
     /// ```
     #[stable(feature = "alloc_layout_manipulation", since = "1.44.0")]
-    #[rustc_const_unstable(feature = "const_alloc_layout", issue = "67521")]
-    #[rustc_const_stable_indirect]
+    #[rustc_const_stable(feature = "const_alloc_layout", since = "CURRENT_RUSTC_VERSION")]
     #[inline]
     pub const fn extend(&self, next: Self) -> Result<(Self, usize), LayoutError> {
         let new_align = Alignment::max(self.align, next.align);
@@ -493,8 +489,7 @@ impl Layout {
     /// On arithmetic overflow or when the total size would exceed
     /// `isize::MAX`, returns `LayoutError`.
     #[stable(feature = "alloc_layout_manipulation", since = "1.44.0")]
-    #[rustc_const_unstable(feature = "const_alloc_layout", issue = "67521")]
-    #[rustc_const_stable_indirect]
+    #[rustc_const_stable(feature = "const_alloc_layout", since = "CURRENT_RUSTC_VERSION")]
     #[inline]
     pub const fn array<T>(n: usize) -> Result<Self, LayoutError> {
         // Reduce the amount of code we need to monomorphize per `T`.