Expand const impls of PartialEq, Eq, PartialOrd and Ord

library/core/src/alloc/layout.rs

@@ -35,7 +35,8 @@ const fn size_align<T>() -> (usize, usize) {
 /// like this are met, use specific allocators with looser
 /// requirements, or use the more lenient `Allocator` interface.)
 #[stable(feature = "alloc_layout", since = "1.28.0")]
-#[derive(Copy, Clone, Debug, PartialEq, Eq, Hash)]
+#[derive(Copy, Debug, Hash)]
+#[derive_const(Clone, PartialEq, Eq)]
 #[lang = "alloc_layout"]
 pub struct Layout {
     // size of the requested block of memory, measured in bytes.
@@ -545,7 +546,8 @@ pub type LayoutErr = LayoutError;
 /// do not satisfy its documented constraints.
 #[stable(feature = "alloc_layout_error", since = "1.50.0")]
 #[non_exhaustive]
-#[derive(Clone, PartialEq, Eq, Debug)]
+#[derive(Debug)]
+#[derive_const(Clone, PartialEq, Eq)]
 pub struct LayoutError;
 
 #[stable(feature = "alloc_layout", since = "1.28.0")]

library/core/src/array/equality.rs

@@ -132,9 +132,8 @@ where
 #[rustc_const_unstable(feature = "const_cmp", issue = "143800")]
 impl<T: [const] Eq, const N: usize> const Eq for [T; N] {}
 
-#[const_trait]
 #[rustc_const_unstable(feature = "const_cmp", issue = "143800")]
-trait SpecArrayEq<Other, const N: usize>: Sized {
+const trait SpecArrayEq<Other, const N: usize>: Sized {
     fn spec_eq(a: &[Self; N], b: &[Other; N]) -> bool;
     fn spec_ne(a: &[Self; N], b: &[Other; N]) -> bool;
 }

library/core/src/array/mod.rs

@@ -403,7 +403,8 @@ where
 
 /// Implements comparison of arrays [lexicographically](Ord#lexicographical-comparison).
 #[stable(feature = "rust1", since = "1.0.0")]
-impl<T: PartialOrd, const N: usize> PartialOrd for [T; N] {
+#[rustc_const_unstable(feature = "const_cmp", issue = "143800")]
+impl<T: [const] PartialOrd, const N: usize> const PartialOrd for [T; N] {
     #[inline]
     fn partial_cmp(&self, other: &[T; N]) -> Option<Ordering> {
         PartialOrd::partial_cmp(&&self[..], &&other[..])
@@ -428,7 +429,8 @@ impl<T: PartialOrd, const N: usize> PartialOrd for [T; N] {
 
 /// Implements comparison of arrays [lexicographically](Ord#lexicographical-comparison).
 #[stable(feature = "rust1", since = "1.0.0")]
-impl<T: Ord, const N: usize> Ord for [T; N] {
+#[rustc_const_unstable(feature = "const_cmp", issue = "143800")]
+impl<T: [const] Ord, const N: usize> const Ord for [T; N] {
     #[inline]
     fn cmp(&self, other: &[T; N]) -> Ordering {
         Ord::cmp(&&self[..], &&other[..])

library/core/src/bstr/traits.rs

@@ -6,31 +6,35 @@ use crate::slice::SliceIndex;
 use crate::{hash, ops, range};
 
 #[unstable(feature = "bstr", issue = "134915")]
-impl Ord for ByteStr {
+#[rustc_const_unstable(feature = "const_cmp", issue = "143800")]
+impl const Ord for ByteStr {
     #[inline]
     fn cmp(&self, other: &ByteStr) -> Ordering {
         Ord::cmp(&self.0, &other.0)
     }
 }
 
 #[unstable(feature = "bstr", issue = "134915")]
-impl PartialOrd for ByteStr {
+#[rustc_const_unstable(feature = "const_cmp", issue = "143800")]
+impl const PartialOrd for ByteStr {
     #[inline]
     fn partial_cmp(&self, other: &ByteStr) -> Option<Ordering> {
         PartialOrd::partial_cmp(&self.0, &other.0)
     }
 }
 
 #[unstable(feature = "bstr", issue = "134915")]
-impl PartialEq<ByteStr> for ByteStr {
+#[rustc_const_unstable(feature = "const_cmp", issue = "143800")]
+impl const PartialEq<ByteStr> for ByteStr {
     #[inline]
     fn eq(&self, other: &ByteStr) -> bool {
         &self.0 == &other.0
     }
 }
 
 #[unstable(feature = "bstr", issue = "134915")]
-impl Eq for ByteStr {}
+#[rustc_const_unstable(feature = "const_cmp", issue = "143800")]
+impl const Eq for ByteStr {}
 
 #[unstable(feature = "bstr", issue = "134915")]
 impl hash::Hash for ByteStr {

library/core/src/char/mod.rs

@@ -591,7 +591,8 @@ impl fmt::Display for CaseMappingIter {
 
 /// The error type returned when a checked char conversion fails.
 #[stable(feature = "u8_from_char", since = "1.59.0")]
-#[derive(Debug, Copy, Clone, PartialEq, Eq)]
+#[derive(Debug, Copy)]
+#[derive_const(Clone, PartialEq, Eq)]
 pub struct TryFromCharError(pub(crate) ());
 
 #[stable(feature = "u8_from_char", since = "1.59.0")]

library/core/src/clone.rs

@@ -575,7 +575,8 @@ mod impls {
         ($($t:ty)*) => {
             $(
                 #[stable(feature = "rust1", since = "1.0.0")]
-                impl Clone for $t {
+                #[rustc_const_unstable(feature = "const_clone", issue = "142757")]
+                impl const Clone for $t {
                     #[inline(always)]
                     fn clone(&self) -> Self {
                         *self
@@ -593,23 +594,26 @@ mod impls {
     }
 
     #[unstable(feature = "never_type", issue = "35121")]
-    impl Clone for ! {
+    #[rustc_const_unstable(feature = "const_clone", issue = "142757")]
+    impl const Clone for ! {
         #[inline]
         fn clone(&self) -> Self {
             *self
         }
     }
 
     #[stable(feature = "rust1", since = "1.0.0")]
-    impl<T: PointeeSized> Clone for *const T {
+    #[rustc_const_unstable(feature = "const_clone", issue = "142757")]
+    impl<T: PointeeSized> const Clone for *const T {
         #[inline(always)]
         fn clone(&self) -> Self {
             *self
         }
     }
 
     #[stable(feature = "rust1", since = "1.0.0")]
-    impl<T: PointeeSized> Clone for *mut T {
+    #[rustc_const_unstable(feature = "const_clone", issue = "142757")]
+    impl<T: PointeeSized> const Clone for *mut T {
         #[inline(always)]
         fn clone(&self) -> Self {
             *self
@@ -618,7 +622,8 @@ mod impls {
 
     /// Shared references can be cloned, but mutable references *cannot*!
     #[stable(feature = "rust1", since = "1.0.0")]
-    impl<T: PointeeSized> Clone for &T {
+    #[rustc_const_unstable(feature = "const_clone", issue = "142757")]
+    impl<T: PointeeSized> const Clone for &T {
         #[inline(always)]
         #[rustc_diagnostic_item = "noop_method_clone"]
         fn clone(&self) -> Self {

library/core/src/ffi/c_str.rs

@@ -88,7 +88,8 @@ use crate::{fmt, ops, slice, str};
 /// ```
 ///
 /// [str]: prim@str "str"
-#[derive(PartialEq, Eq, Hash)]
+#[derive(Hash)]
+#[derive_const(PartialEq, Eq)]
 #[stable(feature = "core_c_str", since = "1.64.0")]
 #[rustc_diagnostic_item = "cstr_type"]
 #[rustc_has_incoherent_inherent_impls]
@@ -669,15 +670,17 @@ impl PartialEq<&Self> for CStr {
 // because `c_char` is `i8` (not `u8`) on some platforms.
 // That is why this is implemented manually and not derived.
 #[stable(feature = "rust1", since = "1.0.0")]
-impl PartialOrd for CStr {
+#[rustc_const_unstable(feature = "const_cmp", issue = "143800")]
+impl const PartialOrd for CStr {
     #[inline]
     fn partial_cmp(&self, other: &CStr) -> Option<Ordering> {
         self.to_bytes().partial_cmp(&other.to_bytes())
     }
 }
 
 #[stable(feature = "rust1", since = "1.0.0")]
-impl Ord for CStr {
+#[rustc_const_unstable(feature = "const_cmp", issue = "143800")]
+impl const Ord for CStr {
     #[inline]
     fn cmp(&self, other: &CStr) -> Ordering {
         self.to_bytes().cmp(&other.to_bytes())

library/core/src/fmt/mod.rs

@@ -21,7 +21,8 @@ mod rt;
 #[stable(feature = "fmt_flags_align", since = "1.28.0")]
 #[rustc_diagnostic_item = "Alignment"]
 /// Possible alignments returned by `Formatter::align`
-#[derive(Copy, Clone, Debug, PartialEq, Eq)]
+#[derive(Copy, Debug)]
+#[derive_const(Clone, PartialEq, Eq)]
 pub enum Alignment {
     #[stable(feature = "fmt_flags_align", since = "1.28.0")]
     /// Indication that contents should be left-aligned.
@@ -103,7 +104,8 @@ pub type Result = result::Result<(), Error>;
 /// }
 /// ```
 #[stable(feature = "rust1", since = "1.0.0")]
-#[derive(Copy, Clone, Debug, Default, Eq, Hash, Ord, PartialEq, PartialOrd)]
+#[derive(Copy, Debug, Hash)]
+#[derive_const(Clone, PartialEq, Eq, PartialOrd, Ord, Default)]
 pub struct Error;
 
 /// A trait for writing or formatting into Unicode-accepting buffers or streams.
@@ -255,7 +257,8 @@ impl<W: Write + ?Sized> Write for &mut W {
 }
 
 /// The signedness of a [`Formatter`] (or of a [`FormattingOptions`]).
-#[derive(Copy, Clone, Debug, PartialEq, Eq)]
+#[derive(Copy, Debug)]
+#[derive_const(Clone, PartialEq, Eq)]
 #[unstable(feature = "formatting_options", issue = "118117")]
 pub enum Sign {
     /// Represents the `+` flag.
@@ -266,7 +269,8 @@ pub enum Sign {
 
 /// Specifies whether the [`Debug`] trait should use lower-/upper-case
 /// hexadecimal or normal integers.
-#[derive(Copy, Clone, Debug, PartialEq, Eq)]
+#[derive(Copy, Debug)]
+#[derive_const(Clone, PartialEq, Eq)]
 #[unstable(feature = "formatting_options", issue = "118117")]
 pub enum DebugAsHex {
     /// Use lower-case hexadecimal integers for the `Debug` trait (like [the `x?` type](../../std/fmt/index.html#formatting-traits)).
@@ -279,7 +283,8 @@ pub enum DebugAsHex {
 ///
 /// `FormattingOptions` is a [`Formatter`] without an attached [`Write`] trait.
 /// It is mainly used to construct `Formatter` instances.
-#[derive(Copy, Clone, Debug, PartialEq, Eq)]
+#[derive(Copy, Debug)]
+#[derive_const(Clone, PartialEq, Eq)]
 #[unstable(feature = "formatting_options", issue = "118117")]
 pub struct FormattingOptions {
     /// Flags, with the following bit fields:

library/core/src/intrinsics/mod.rs

@@ -71,7 +71,8 @@ use crate::sync::atomic::{self, AtomicBool, AtomicI32, AtomicIsize, AtomicU32, O
 /// A type for atomic ordering parameters for intrinsics. This is a separate type from
 /// `atomic::Ordering` so that we can make it `ConstParamTy` and fix the values used here without a
 /// risk of leaking that to stable code.
-#[derive(Debug, ConstParamTy, PartialEq, Eq)]
+#[derive(Debug, ConstParamTy)]
+#[derive_const(PartialEq, Eq)]
 pub enum AtomicOrdering {
     // These values must match the compiler's `AtomicOrdering` defined in
     // `rustc_middle/src/ty/consts/int.rs`!

library/core/src/marker.rs

@@ -828,24 +828,28 @@ impl<T: PointeeSized> Hash for PhantomData<T> {
 }
 
 #[stable(feature = "rust1", since = "1.0.0")]
-impl<T: PointeeSized> cmp::PartialEq for PhantomData<T> {
+#[rustc_const_unstable(feature = "const_cmp", issue = "143800")]
+impl<T: PointeeSized> const cmp::PartialEq for PhantomData<T> {
     fn eq(&self, _other: &PhantomData<T>) -> bool {
         true
     }
 }
 
 #[stable(feature = "rust1", since = "1.0.0")]
-impl<T: PointeeSized> cmp::Eq for PhantomData<T> {}
+#[rustc_const_unstable(feature = "const_cmp", issue = "143800")]
+impl<T: PointeeSized> const cmp::Eq for PhantomData<T> {}
 
 #[stable(feature = "rust1", since = "1.0.0")]
-impl<T: PointeeSized> cmp::PartialOrd for PhantomData<T> {
+#[rustc_const_unstable(feature = "const_cmp", issue = "143800")]
+impl<T: PointeeSized> const cmp::PartialOrd for PhantomData<T> {
     fn partial_cmp(&self, _other: &PhantomData<T>) -> Option<cmp::Ordering> {
         Option::Some(cmp::Ordering::Equal)
     }
 }
 
 #[stable(feature = "rust1", since = "1.0.0")]
-impl<T: PointeeSized> cmp::Ord for PhantomData<T> {
+#[rustc_const_unstable(feature = "const_cmp", issue = "143800")]
+impl<T: PointeeSized> const cmp::Ord for PhantomData<T> {
     fn cmp(&self, _other: &PhantomData<T>) -> cmp::Ordering {
         cmp::Ordering::Equal
     }
@@ -1021,7 +1025,8 @@ pub auto trait Unpin {}
 // marker in your struct acts as if you wrapped the entire struct in an `UnsafePinned`. This type
 // will likely eventually be deprecated, and all new code should be using `UnsafePinned` instead.
 #[stable(feature = "pin", since = "1.33.0")]
-#[derive(Debug, Default, Copy, Clone, Eq, PartialEq, Ord, PartialOrd, Hash)]
+#[derive(Debug, Copy, Hash)]
+#[derive_const(Clone, PartialEq, Eq, PartialOrd, Ord, Default)]
 pub struct PhantomPinned;
 
 #[stable(feature = "pin", since = "1.33.0")]

library/core/src/mem/manually_drop.rs

@@ -151,7 +151,8 @@ use crate::ptr;
 /// [`MaybeUninit`]: crate::mem::MaybeUninit
 #[stable(feature = "manually_drop", since = "1.20.0")]
 #[lang = "manually_drop"]
-#[derive(Copy, Clone, Debug, Default, PartialEq, Eq, PartialOrd, Ord, Hash)]
+#[derive(Copy, Debug, Hash)]
+#[derive_const(Clone, PartialEq, Eq, PartialOrd, Ord, Default)]
 #[repr(transparent)]
 #[rustc_pub_transparent]
 pub struct ManuallyDrop<T: ?Sized> {

library/core/src/mem/transmutability.rs

@@ -147,7 +147,8 @@ where
 /// `true`, the onus of the safety proof belongs to the programmer.
 #[unstable(feature = "transmutability", issue = "99571")]
 #[lang = "transmute_opts"]
-#[derive(PartialEq, Eq, Clone, Copy, Debug)]
+#[derive(Copy, Debug)]
+#[derive_const(Clone, PartialEq, Eq)]
 pub struct Assume {
     /// When `false`, [`TransmuteFrom`] is not implemented for transmutations
     /// that might violate the alignment requirements of references; e.g.: