Added const versions of common numeric operations

# Conflicts:
#	library/core/src/lib.rs

6 files changed, 232 insertions, 106 deletions

diff --git a/library/core/src/internal_macros.rs b/library/core/src/internal_macros.rs
index be12f904640..b5c1bf6897c 100644
--- a/library/core/src/internal_macros.rs
+++ b/library/core/src/internal_macros.rs
@@ -5,6 +5,22 @@ macro_rules! forward_ref_unop {
         forward_ref_unop!(impl $imp, $method for $t,
                 #[stable(feature = "rust1", since = "1.0.0")]);
     };
+    (impl const $imp:ident, $method:ident for $t:ty) => {
+        forward_ref_unop!(impl const $imp, $method for $t,
+                #[stable(feature = "rust1", since = "1.0.0")]);
+    };
+    (impl const $imp:ident, $method:ident for $t:ty, #[$attr:meta]) => {
+        #[$attr]
+        #[rustc_const_unstable(feature = "const_ops", issue = "90080")]
+        impl const $imp for &$t {
+            type Output = <$t as $imp>::Output;
+
+            #[inline]
+            fn $method(self) -> <$t as $imp>::Output {
+                $imp::$method(*self)
+            }
+        }
+    };
     (impl $imp:ident, $method:ident for $t:ty, #[$attr:meta]) => {
         #[$attr]
         impl $imp for &$t {
@@ -25,6 +41,44 @@ macro_rules! forward_ref_binop {
         forward_ref_binop!(impl $imp, $method for $t, $u,
                 #[stable(feature = "rust1", since = "1.0.0")]);
     };
+    (impl const $imp:ident, $method:ident for $t:ty, $u:ty) => {
+        forward_ref_binop!(impl const $imp, $method for $t, $u,
+                #[stable(feature = "rust1", since = "1.0.0")]);
+    };
+    (impl const $imp:ident, $method:ident for $t:ty, $u:ty, #[$attr:meta]) => {
+        #[$attr]
+        #[rustc_const_unstable(feature = "const_ops", issue = "90080")]
+        impl<'a> const $imp<$u> for &'a $t {
+            type Output = <$t as $imp<$u>>::Output;
+
+            #[inline]
+            fn $method(self, other: $u) -> <$t as $imp<$u>>::Output {
+                $imp::$method(*self, other)
+            }
+        }
+
+        #[$attr]
+        #[rustc_const_unstable(feature = "const_ops", issue = "90080")]
+        impl const $imp<&$u> for $t {
+            type Output = <$t as $imp<$u>>::Output;
+
+            #[inline]
+            fn $method(self, other: &$u) -> <$t as $imp<$u>>::Output {
+                $imp::$method(self, *other)
+            }
+        }
+
+        #[$attr]
+        #[rustc_const_unstable(feature = "const_ops", issue = "90080")]
+        impl const $imp<&$u> for &$t {
+            type Output = <$t as $imp<$u>>::Output;
+
+            #[inline]
+            fn $method(self, other: &$u) -> <$t as $imp<$u>>::Output {
+                $imp::$method(*self, *other)
+            }
+        }
+    };
     (impl $imp:ident, $method:ident for $t:ty, $u:ty, #[$attr:meta]) => {
         #[$attr]
         impl<'a> $imp<$u> for &'a $t {
@@ -65,6 +119,20 @@ macro_rules! forward_ref_op_assign {
         forward_ref_op_assign!(impl $imp, $method for $t, $u,
                 #[stable(feature = "op_assign_builtins_by_ref", since = "1.22.0")]);
     };
+    (impl const $imp:ident, $method:ident for $t:ty, $u:ty) => {
+        forward_ref_op_assign!(impl const $imp, $method for $t, $u,
+                #[stable(feature = "op_assign_builtins_by_ref", since = "1.22.0")]);
+    };
+    (impl const $imp:ident, $method:ident for $t:ty, $u:ty, #[$attr:meta]) => {
+        #[$attr]
+        #[rustc_const_unstable(feature = "const_ops", issue = "90080")]
+        impl const $imp<&$u> for $t {
+            #[inline]
+            fn $method(&mut self, other: &$u) {
+                $imp::$method(self, *other);
+            }
+        }
+    };
     (impl $imp:ident, $method:ident for $t:ty, $u:ty, #[$attr:meta]) => {
         #[$attr]
         impl $imp<&$u> for $t {
diff --git a/library/core/src/lib.rs b/library/core/src/lib.rs
index 58a170401e7..87857873dfd 100644
--- a/library/core/src/lib.rs
+++ b/library/core/src/lib.rs
@@ -116,6 +116,7 @@
 #![feature(const_maybe_uninit_as_ptr)]
 #![feature(const_maybe_uninit_assume_init)]
 #![feature(const_num_from_num)]
+#![feature(const_ops)]
 #![feature(const_option)]
 #![feature(const_pin)]
 #![feature(const_replace)]
diff --git a/library/core/src/num/nonzero.rs b/library/core/src/num/nonzero.rs
index 9b1a4de5d80..7708094e1fc 100644
--- a/library/core/src/num/nonzero.rs
+++ b/library/core/src/num/nonzero.rs
@@ -92,7 +92,8 @@ macro_rules! nonzero_integers {
             }
 
             #[stable(feature = "nonzero_bitor", since = "1.45.0")]
-            impl BitOr for $Ty {
+            #[rustc_const_unstable(feature = "const_ops", issue = "90080")]
+            impl const BitOr for $Ty {
                 type Output = Self;
                 #[inline]
                 fn bitor(self, rhs: Self) -> Self::Output {
@@ -103,7 +104,8 @@ macro_rules! nonzero_integers {
             }
 
             #[stable(feature = "nonzero_bitor", since = "1.45.0")]
-            impl BitOr<$Int> for $Ty {
+            #[rustc_const_unstable(feature = "const_ops", issue = "90080")]
+            impl const BitOr<$Int> for $Ty {
                 type Output = Self;
                 #[inline]
                 fn bitor(self, rhs: $Int) -> Self::Output {
@@ -115,7 +117,8 @@ macro_rules! nonzero_integers {
             }
 
             #[stable(feature = "nonzero_bitor", since = "1.45.0")]
-            impl BitOr<$Ty> for $Int {
+            #[rustc_const_unstable(feature = "const_ops", issue = "90080")]
+            impl const BitOr<$Ty> for $Int {
                 type Output = $Ty;
                 #[inline]
                 fn bitor(self, rhs: $Ty) -> Self::Output {
@@ -127,7 +130,8 @@ macro_rules! nonzero_integers {
             }
 
             #[stable(feature = "nonzero_bitor", since = "1.45.0")]
-            impl BitOrAssign for $Ty {
+            #[rustc_const_unstable(feature = "const_ops", issue = "90080")]
+            impl const BitOrAssign for $Ty {
                 #[inline]
                 fn bitor_assign(&mut self, rhs: Self) {
                     *self = *self | rhs;
@@ -135,7 +139,8 @@ macro_rules! nonzero_integers {
             }
 
             #[stable(feature = "nonzero_bitor", since = "1.45.0")]
-            impl BitOrAssign<$Int> for $Ty {
+            #[rustc_const_unstable(feature = "const_ops", issue = "90080")]
+            impl const BitOrAssign<$Int> for $Ty {
                 #[inline]
                 fn bitor_assign(&mut self, rhs: $Int) {
                     *self = *self | rhs;
@@ -257,7 +262,8 @@ macro_rules! nonzero_integers_div {
     ( $( $Ty: ident($Int: ty); )+ ) => {
         $(
             #[stable(feature = "nonzero_div", since = "1.51.0")]
-            impl Div<$Ty> for $Int {
+            #[rustc_const_unstable(feature = "const_ops", issue = "90080")]
+            impl const Div<$Ty> for $Int {
                 type Output = $Int;
                 /// This operation rounds towards zero,
                 /// truncating any fractional part of the exact result, and cannot panic.
@@ -270,7 +276,8 @@ macro_rules! nonzero_integers_div {
             }
 
             #[stable(feature = "nonzero_div", since = "1.51.0")]
-            impl Rem<$Ty> for $Int {
+            #[rustc_const_unstable(feature = "const_ops", issue = "90080")]
+            impl const Rem<$Ty> for $Int {
                 type Output = $Int;
                 /// This operation satisfies `n % d == n - (n / d) * d`, and cannot panic.
                 #[inline]
diff --git a/library/core/src/num/wrapping.rs b/library/core/src/num/wrapping.rs
index f387bd5b41c..a0e42c51e45 100644
--- a/library/core/src/num/wrapping.rs
+++ b/library/core/src/num/wrapping.rs
@@ -87,7 +87,8 @@ impl<T: fmt::UpperHex> fmt::UpperHex for Wrapping<T> {
 macro_rules! sh_impl_signed {
     ($t:ident, $f:ident) => {
         #[stable(feature = "rust1", since = "1.0.0")]
-        impl Shl<$f> for Wrapping<$t> {
+        #[rustc_const_unstable(feature = "const_ops", issue = "90080")]
+        impl const Shl<$f> for Wrapping<$t> {
             type Output = Wrapping<$t>;
 
             #[inline]
@@ -99,20 +100,22 @@ macro_rules! sh_impl_signed {
                 }
             }
         }
-        forward_ref_binop! { impl Shl, shl for Wrapping<$t>, $f,
+        forward_ref_binop! { impl const Shl, shl for Wrapping<$t>, $f,
         #[stable(feature = "wrapping_ref_ops", since = "1.39.0")] }
 
         #[stable(feature = "op_assign_traits", since = "1.8.0")]
-        impl ShlAssign<$f> for Wrapping<$t> {
+        #[rustc_const_unstable(feature = "const_ops", issue = "90080")]
+        impl const ShlAssign<$f> for Wrapping<$t> {
             #[inline]
             fn shl_assign(&mut self, other: $f) {
                 *self = *self << other;
             }
         }
-        forward_ref_op_assign! { impl ShlAssign, shl_assign for Wrapping<$t>, $f }
+        forward_ref_op_assign! { impl const ShlAssign, shl_assign for Wrapping<$t>, $f }
 
         #[stable(feature = "rust1", since = "1.0.0")]
-        impl Shr<$f> for Wrapping<$t> {
+        #[rustc_const_unstable(feature = "const_ops", issue = "90080")]
+        impl const Shr<$f> for Wrapping<$t> {
             type Output = Wrapping<$t>;
 
             #[inline]
@@ -124,24 +127,26 @@ macro_rules! sh_impl_signed {
                 }
             }
         }
-        forward_ref_binop! { impl Shr, shr for Wrapping<$t>, $f,
+        forward_ref_binop! { impl const Shr, shr for Wrapping<$t>, $f,
         #[stable(feature = "wrapping_ref_ops", since = "1.39.0")] }
 
         #[stable(feature = "op_assign_traits", since = "1.8.0")]
-        impl ShrAssign<$f> for Wrapping<$t> {
+        #[rustc_const_unstable(feature = "const_ops", issue = "90080")]
+        impl const ShrAssign<$f> for Wrapping<$t> {
             #[inline]
             fn shr_assign(&mut self, other: $f) {
                 *self = *self >> other;
             }
         }
-        forward_ref_op_assign! { impl ShrAssign, shr_assign for Wrapping<$t>, $f }
+        forward_ref_op_assign! { impl const ShrAssign, shr_assign for Wrapping<$t>, $f }
     };
 }
 
 macro_rules! sh_impl_unsigned {
     ($t:ident, $f:ident) => {
         #[stable(feature = "rust1", since = "1.0.0")]
-        impl Shl<$f> for Wrapping<$t> {
+        #[rustc_const_unstable(feature = "const_ops", issue = "90080")]
+        impl const Shl<$f> for Wrapping<$t> {
             type Output = Wrapping<$t>;
 
             #[inline]
@@ -149,20 +154,22 @@ macro_rules! sh_impl_unsigned {
                 Wrapping(self.0.wrapping_shl((other & self::shift_max::$t as $f) as u32))
             }
         }
-        forward_ref_binop! { impl Shl, shl for Wrapping<$t>, $f,
+        forward_ref_binop! { impl const Shl, shl for Wrapping<$t>, $f,
         #[stable(feature = "wrapping_ref_ops", since = "1.39.0")] }
 
         #[stable(feature = "op_assign_traits", since = "1.8.0")]
-        impl ShlAssign<$f> for Wrapping<$t> {
+        #[rustc_const_unstable(feature = "const_ops", issue = "90080")]
+        impl const ShlAssign<$f> for Wrapping<$t> {
             #[inline]
             fn shl_assign(&mut self, other: $f) {
                 *self = *self << other;
             }
         }
-        forward_ref_op_assign! { impl ShlAssign, shl_assign for Wrapping<$t>, $f }
+        forward_ref_op_assign! { impl const ShlAssign, shl_assign for Wrapping<$t>, $f }
 
         #[stable(feature = "rust1", since = "1.0.0")]
-        impl Shr<$f> for Wrapping<$t> {
+        #[rustc_const_unstable(feature = "const_ops", issue = "90080")]
+        impl const Shr<$f> for Wrapping<$t> {
             type Output = Wrapping<$t>;
 
             #[inline]
@@ -170,17 +177,18 @@ macro_rules! sh_impl_unsigned {
                 Wrapping(self.0.wrapping_shr((other & self::shift_max::$t as $f) as u32))
             }
         }
-        forward_ref_binop! { impl Shr, shr for Wrapping<$t>, $f,
+        forward_ref_binop! { impl const Shr, shr for Wrapping<$t>, $f,
         #[stable(feature = "wrapping_ref_ops", since = "1.39.0")] }
 
         #[stable(feature = "op_assign_traits", since = "1.8.0")]
-        impl ShrAssign<$f> for Wrapping<$t> {
+        #[rustc_const_unstable(feature = "const_ops", issue = "90080")]
+        impl const ShrAssign<$f> for Wrapping<$t> {
             #[inline]
             fn shr_assign(&mut self, other: $f) {
                 *self = *self >> other;
             }
         }
-        forward_ref_op_assign! { impl ShrAssign, shr_assign for Wrapping<$t>, $f }
+        forward_ref_op_assign! { impl const ShrAssign, shr_assign for Wrapping<$t>, $f }
     };
 }
 
@@ -209,7 +217,8 @@ sh_impl_all! { u8 u16 u32 u64 u128 usize i8 i16 i32 i64 i128 isize }
 macro_rules! wrapping_impl {
     ($($t:ty)*) => ($(
         #[stable(feature = "rust1", since = "1.0.0")]
-        impl Add for Wrapping<$t> {
+        #[rustc_const_unstable(feature = "const_ops", issue = "90080")]
+        impl const Add for Wrapping<$t> {
             type Output = Wrapping<$t>;
 
             #[inline]
@@ -217,20 +226,22 @@ macro_rules! wrapping_impl {
                 Wrapping(self.0.wrapping_add(other.0))
             }
         }
-        forward_ref_binop! { impl Add, add for Wrapping<$t>, Wrapping<$t>,
+        forward_ref_binop! { impl const Add, add for Wrapping<$t>, Wrapping<$t>,
                 #[stable(feature = "wrapping_ref", since = "1.14.0")] }
 
         #[stable(feature = "op_assign_traits", since = "1.8.0")]
-        impl AddAssign for Wrapping<$t> {
+        #[rustc_const_unstable(feature = "const_ops", issue = "90080")]
+        impl const AddAssign for Wrapping<$t> {
             #[inline]
             fn add_assign(&mut self, other: Wrapping<$t>) {
                 *self = *self + other;
             }
         }
-        forward_ref_op_assign! { impl AddAssign, add_assign for Wrapping<$t>, Wrapping<$t> }
+        forward_ref_op_assign! { impl const AddAssign, add_assign for Wrapping<$t>, Wrapping<$t> }
 
         #[stable(feature = "rust1", since = "1.0.0")]
-        impl Sub for Wrapping<$t> {
+        #[rustc_const_unstable(feature = "const_ops", issue = "90080")]
+        impl const Sub for Wrapping<$t> {
             type Output = Wrapping<$t>;
 
             #[inline]
@@ -238,20 +249,22 @@ macro_rules! wrapping_impl {
                 Wrapping(self.0.wrapping_sub(other.0))
             }
         }
-        forward_ref_binop! { impl Sub, sub for Wrapping<$t>, Wrapping<$t>,
+        forward_ref_binop! { impl const Sub, sub for Wrapping<$t>, Wrapping<$t>,
                 #[stable(feature = "wrapping_ref", since = "1.14.0")] }
 
         #[stable(feature = "op_assign_traits", since = "1.8.0")]
-        impl SubAssign for Wrapping<$t> {
+        #[rustc_const_unstable(feature = "const_ops", issue = "90080")]
+        impl const SubAssign for Wrapping<$t> {
             #[inline]
             fn sub_assign(&mut self, other: Wrapping<$t>) {
                 *self = *self - other;
             }
         }
-        forward_ref_op_assign! { impl SubAssign, sub_assign for Wrapping<$t>, Wrapping<$t> }
+        forward_ref_op_assign! { impl const SubAssign, sub_assign for Wrapping<$t>, Wrapping<$t> }
 
         #[stable(feature = "rust1", since = "1.0.0")]
-        impl Mul for Wrapping<$t> {
+        #[rustc_const_unstable(feature = "const_ops", issue = "90080")]
+        impl const Mul for Wrapping<$t> {
             type Output = Wrapping<$t>;
 
             #[inline]
@@ -263,16 +276,18 @@ macro_rules! wrapping_impl {
                 #[stable(feature = "wrapping_ref", since = "1.14.0")] }
 
         #[stable(feature = "op_assign_traits", since = "1.8.0")]
-        impl MulAssign for Wrapping<$t> {
+        #[rustc_const_unstable(feature = "const_ops", issue = "90080")]
+        impl const MulAssign for Wrapping<$t> {
             #[inline]
             fn mul_assign(&mut self, other: Wrapping<$t>) {
                 *self = *self * other;
             }
         }
-        forward_ref_op_assign! { impl MulAssign, mul_assign for Wrapping<$t>, Wrapping<$t> }
+        forward_ref_op_assign! { impl const MulAssign, mul_assign for Wrapping<$t>, Wrapping<$t> }
 
         #[stable(feature = "wrapping_div", since = "1.3.0")]
-        impl Div for Wrapping<$t> {
+        #[rustc_const_unstable(feature = "const_ops", issue = "90080")]
+        impl const Div for Wrapping<$t> {
             type Output = Wrapping<$t>;
 
             #[inline]
@@ -280,20 +295,22 @@ macro_rules! wrapping_impl {
                 Wrapping(self.0.wrapping_div(other.0))
             }
         }
-        forward_ref_binop! { impl Div, div for Wrapping<$t>, Wrapping<$t>,
+        forward_ref_binop! { impl const Div, div for Wrapping<$t>, Wrapping<$t>,
                 #[stable(feature = "wrapping_ref", since = "1.14.0")] }
 
         #[stable(feature = "op_assign_traits", since = "1.8.0")]
-        impl DivAssign for Wrapping<$t> {
+        #[rustc_const_unstable(feature = "const_ops", issue = "90080")]
+        impl const DivAssign for Wrapping<$t> {
             #[inline]
             fn div_assign(&mut self, other: Wrapping<$t>) {
                 *self = *self / other;
             }
         }
-        forward_ref_op_assign! { impl DivAssign, div_assign for Wrapping<$t>, Wrapping<$t> }
+        forward_ref_op_assign! { impl const DivAssign, div_assign for Wrapping<$t>, Wrapping<$t> }
 
         #[stable(feature = "wrapping_impls", since = "1.7.0")]
-        impl Rem for Wrapping<$t> {
+        #[rustc_const_unstable(feature = "const_ops", issue = "90080")]
+        impl const Rem for Wrapping<$t> {
             type Output = Wrapping<$t>;
 
             #[inline]
@@ -301,20 +318,22 @@ macro_rules! wrapping_impl {
                 Wrapping(self.0.wrapping_rem(other.0))
             }
         }
-        forward_ref_binop! { impl Rem, rem for Wrapping<$t>, Wrapping<$t>,
+        forward_ref_binop! { impl const Rem, rem for Wrapping<$t>, Wrapping<$t>,
                 #[stable(feature = "wrapping_ref", since = "1.14.0")] }
 
         #[stable(feature = "op_assign_traits", since = "1.8.0")]
-        impl RemAssign for Wrapping<$t> {
+        #[rustc_const_unstable(feature = "const_ops", issue = "90080")]
+        impl const RemAssign for Wrapping<$t> {
             #[inline]
             fn rem_assign(&mut self, other: Wrapping<$t>) {
                 *self = *self % other;
             }
         }
-        forward_ref_op_assign! { impl RemAssign, rem_assign for Wrapping<$t>, Wrapping<$t> }
+        forward_ref_op_assign! { impl const RemAssign, rem_assign for Wrapping<$t>, Wrapping<$t> }
 
         #[stable(feature = "rust1", since = "1.0.0")]
-        impl Not for Wrapping<$t> {
+        #[rustc_const_unstable(feature = "const_ops", issue = "90080")]
+        impl const Not for Wrapping<$t> {
             type Output = Wrapping<$t>;
 
             #[inline]
@@ -322,11 +341,12 @@ macro_rules! wrapping_impl {
                 Wrapping(!self.0)
             }
         }
-        forward_ref_unop! { impl Not, not for Wrapping<$t>,
+        forward_ref_unop! { impl const Not, not for Wrapping<$t>,
                 #[stable(feature = "wrapping_ref", since = "1.14.0")] }
 
         #[stable(feature = "rust1", since = "1.0.0")]
-        impl BitXor for Wrapping<$t> {
+        #[rustc_const_unstable(feature = "const_ops", issue = "90080")]
+        impl const BitXor for Wrapping<$t> {
             type Output = Wrapping<$t>;
 
             #[inline]
@@ -334,20 +354,22 @@ macro_rules! wrapping_impl {
                 Wrapping(self.0 ^ other.0)
             }
         }
-        forward_ref_binop! { impl BitXor, bitxor for Wrapping<$t>, Wrapping<$t>,
+        forward_ref_binop! { impl const BitXor, bitxor for Wrapping<$t>, Wrapping<$t>,
                 #[stable(feature = "wrapping_ref", since = "1.14.0")] }
 
         #[stable(feature = "op_assign_traits", since = "1.8.0")]
-        impl BitXorAssign for Wrapping<$t> {
+        #[rustc_const_unstable(feature = "const_ops", issue = "90080")]
+        impl const BitXorAssign for Wrapping<$t> {
             #[inline]
             fn bitxor_assign(&mut self, other: Wrapping<$t>) {
                 *self = *self ^ other;
             }
         }
-        forward_ref_op_assign! { impl BitXorAssign, bitxor_assign for Wrapping<$t>, Wrapping<$t> }
+        forward_ref_op_assign! { impl const BitXorAssign, bitxor_assign for Wrapping<$t>, Wrapping<$t> }
 
         #[stable(feature = "rust1", since = "1.0.0")]
-        impl BitOr for Wrapping<$t> {
+        #[rustc_const_unstable(feature = "const_ops", issue = "90080")]
+        impl const BitOr for Wrapping<$t> {
             type Output = Wrapping<$t>;
 
             #[inline]
@@ -355,20 +377,22 @@ macro_rules! wrapping_impl {
                 Wrapping(self.0 | other.0)
             }
         }
-        forward_ref_binop! { impl BitOr, bitor for Wrapping<$t>, Wrapping<$t>,
+        forward_ref_binop! { impl const BitOr, bitor for Wrapping<$t>, Wrapping<$t>,
                 #[stable(feature = "wrapping_ref", since = "1.14.0")] }
 
         #[stable(feature = "op_assign_traits", since = "1.8.0")]
-        impl BitOrAssign for Wrapping<$t> {
+        #[rustc_const_unstable(feature = "const_ops", issue = "90080")]
+        impl const BitOrAssign for Wrapping<$t> {
             #[inline]
             fn bitor_assign(&mut self, other: Wrapping<$t>) {
                 *self = *self | other;
             }
         }
-        forward_ref_op_assign! { impl BitOrAssign, bitor_assign for Wrapping<$t>, Wrapping<$t> }
+        forward_ref_op_assign! { impl const BitOrAssign, bitor_assign for Wrapping<$t>, Wrapping<$t> }
 
         #[stable(feature = "rust1", since = "1.0.0")]
-        impl BitAnd for Wrapping<$t> {
+        #[rustc_const_unstable(feature = "const_ops", issue = "90080")]
+        impl const BitAnd for Wrapping<$t> {
             type Output = Wrapping<$t>;
 
             #[inline]
@@ -376,27 +400,29 @@ macro_rules! wrapping_impl {
                 Wrapping(self.0 & other.0)
             }
         }
-        forward_ref_binop! { impl BitAnd, bitand for Wrapping<$t>, Wrapping<$t>,
+        forward_ref_binop! { impl const BitAnd, bitand for Wrapping<$t>, Wrapping<$t>,
                 #[stable(feature = "wrapping_ref", since = "1.14.0")] }
 
         #[stable(feature = "op_assign_traits", since = "1.8.0")]
-        impl BitAndAssign for Wrapping<$t> {
+        #[rustc_const_unstable(feature = "const_ops", issue = "90080")]
+        impl const BitAndAssign for Wrapping<$t> {
             #[inline]
             fn bitand_assign(&mut self, other: Wrapping<$t>) {
                 *self = *self & other;
             }
         }
-        forward_ref_op_assign! { impl BitAndAssign, bitand_assign for Wrapping<$t>, Wrapping<$t> }
+        forward_ref_op_assign! { impl const BitAndAssign, bitand_assign for Wrapping<$t>, Wrapping<$t> }
 
         #[stable(feature = "wrapping_neg", since = "1.10.0")]
-        impl Neg for Wrapping<$t> {
+        #[rustc_const_unstable(feature = "const_ops", issue = "90080")]
+        impl const Neg for Wrapping<$t> {
             type Output = Self;
             #[inline]
             fn neg(self) -> Self {
                 Wrapping(0) - self
             }
         }
-        forward_ref_unop! { impl Neg, neg for Wrapping<$t>,
+        forward_ref_unop! { impl const Neg, neg for Wrapping<$t>,
                 #[stable(feature = "wrapping_ref", since = "1.14.0")] }
 
     )*)
diff --git a/library/core/src/ops/arith.rs b/library/core/src/ops/arith.rs
index a0577b287ce..e9547429389 100644
--- a/library/core/src/ops/arith.rs
+++ b/library/core/src/ops/arith.rs
@@ -92,7 +92,8 @@ pub trait Add<Rhs = Self> {
 macro_rules! add_impl {
     ($($t:ty)*) => ($(
         #[stable(feature = "rust1", since = "1.0.0")]
-        impl Add for $t {
+        #[rustc_const_unstable(feature = "const_ops", issue = "90080")]
+        impl const Add for $t {
             type Output = $t;
 
             #[inline]
@@ -100,7 +101,7 @@ macro_rules! add_impl {
             fn add(self, other: $t) -> $t { self + other }
         }
 
-        forward_ref_binop! { impl Add, add for $t, $t }
+        forward_ref_binop! { impl const Add, add for $t, $t }
     )*)
 }
 
@@ -198,7 +199,8 @@ pub trait Sub<Rhs = Self> {
 macro_rules! sub_impl {
     ($($t:ty)*) => ($(
         #[stable(feature = "rust1", since = "1.0.0")]
-        impl Sub for $t {
+        #[rustc_const_unstable(feature = "const_ops", issue = "90080")]
+        impl const Sub for $t {
             type Output = $t;
 
             #[inline]
@@ -206,7 +208,7 @@ macro_rules! sub_impl {
             fn sub(self, other: $t) -> $t { self - other }
         }
 
-        forward_ref_binop! { impl Sub, sub for $t, $t }
+        forward_ref_binop! { impl const Sub, sub for $t, $t }
     )*)
 }
 
@@ -326,7 +328,8 @@ pub trait Mul<Rhs = Self> {
 macro_rules! mul_impl {
     ($($t:ty)*) => ($(
         #[stable(feature = "rust1", since = "1.0.0")]
-        impl Mul for $t {
+        #[rustc_const_unstable(feature = "const_ops", issue = "90080")]
+        impl const Mul for $t {
             type Output = $t;
 
             #[inline]
@@ -334,7 +337,7 @@ macro_rules! mul_impl {
             fn mul(self, other: $t) -> $t { self * other }
         }
 
-        forward_ref_binop! { impl Mul, mul for $t, $t }
+        forward_ref_binop! { impl const Mul, mul for $t, $t }
     )*)
 }
 
@@ -464,14 +467,15 @@ macro_rules! div_impl_integer {
         ///
         #[doc = $panic]
         #[stable(feature = "rust1", since = "1.0.0")]
-        impl Div for $t {
+        #[rustc_const_unstable(feature = "const_ops", issue = "90080")]
+        impl const Div for $t {
             type Output = $t;
 
             #[inline]
             fn div(self, other: $t) -> $t { self / other }
         }
 
-        forward_ref_binop! { impl Div, div for $t, $t }
+        forward_ref_binop! { impl const Div, div for $t, $t }
     )*)*)
 }
 
@@ -483,14 +487,15 @@ div_impl_integer! {
 macro_rules! div_impl_float {
     ($($t:ty)*) => ($(
         #[stable(feature = "rust1", since = "1.0.0")]
-        impl Div for $t {
+        #[rustc_const_unstable(feature = "const_ops", issue = "90080")]
+        impl const Div for $t {
             type Output = $t;
 
             #[inline]
             fn div(self, other: $t) -> $t { self / other }
         }
 
-        forward_ref_binop! { impl Div, div for $t, $t }
+        forward_ref_binop! { impl const Div, div for $t, $t }
     )*)
 }
 
@@ -564,14 +569,15 @@ macro_rules! rem_impl_integer {
         ///
         #[doc = $panic]
         #[stable(feature = "rust1", since = "1.0.0")]
-        impl Rem for $t {
+        #[rustc_const_unstable(feature = "const_ops", issue = "90080")]
+        impl const Rem for $t {
             type Output = $t;
 
             #[inline]
             fn rem(self, other: $t) -> $t { self % other }
         }
 
-        forward_ref_binop! { impl Rem, rem for $t, $t }
+        forward_ref_binop! { impl const Rem, rem for $t, $t }
     )*)*)
 }
 
@@ -598,14 +604,15 @@ macro_rules! rem_impl_float {
         /// assert_eq!(x % y, remainder);
         /// ```
         #[stable(feature = "rust1", since = "1.0.0")]
-        impl Rem for $t {
+        #[rustc_const_unstable(feature = "const_ops", issue = "90080")]
+        impl const Rem for $t {
             type Output = $t;
 
             #[inline]
             fn rem(self, other: $t) -> $t { self % other }
         }
 
-        forward_ref_binop! { impl Rem, rem for $t, $t }
+        forward_ref_binop! { impl const Rem, rem for $t, $t }
     )*)
 }
 
@@ -671,7 +678,8 @@ pub trait Neg {
 macro_rules! neg_impl {
     ($($t:ty)*) => ($(
         #[stable(feature = "rust1", since = "1.0.0")]
-        impl Neg for $t {
+        #[rustc_const_unstable(feature = "const_ops", issue = "90080")]
+        impl const Neg for $t {
             type Output = $t;
 
             #[inline]
@@ -679,7 +687,7 @@ macro_rules! neg_impl {
             fn neg(self) -> $t { -self }
         }
 
-        forward_ref_unop! { impl Neg, neg for $t }
+        forward_ref_unop! { impl const Neg, neg for $t }
     )*)
 }
 
@@ -739,13 +747,14 @@ pub trait AddAssign<Rhs = Self> {
 macro_rules! add_assign_impl {
     ($($t:ty)+) => ($(
         #[stable(feature = "op_assign_traits", since = "1.8.0")]
-        impl AddAssign for $t {
+        #[rustc_const_unstable(feature = "const_ops", issue = "90080")]
+        impl const AddAssign for $t {
             #[inline]
             #[rustc_inherit_overflow_checks]
             fn add_assign(&mut self, other: $t) { *self += other }
         }
 
-        forward_ref_op_assign! { impl AddAssign, add_assign for $t, $t }
+        forward_ref_op_assign! { impl const AddAssign, add_assign for $t, $t }
     )+)
 }
 
@@ -805,13 +814,14 @@ pub trait SubAssign<Rhs = Self> {
 macro_rules! sub_assign_impl {
     ($($t:ty)+) => ($(
         #[stable(feature = "op_assign_traits", since = "1.8.0")]
-        impl SubAssign for $t {
+        #[rustc_const_unstable(feature = "const_ops", issue = "90080")]
+        impl const SubAssign for $t {
             #[inline]
             #[rustc_inherit_overflow_checks]
             fn sub_assign(&mut self, other: $t) { *self -= other }
         }
 
-        forward_ref_op_assign! { impl SubAssign, sub_assign for $t, $t }
+        forward_ref_op_assign! { impl const SubAssign, sub_assign for $t, $t }
     )+)
 }
 
@@ -862,13 +872,14 @@ pub trait MulAssign<Rhs = Self> {
 macro_rules! mul_assign_impl {
     ($($t:ty)+) => ($(
         #[stable(feature = "op_assign_traits", since = "1.8.0")]
-        impl MulAssign for $t {
+        #[rustc_const_unstable(feature = "const_ops", issue = "90080")]
+        impl const MulAssign for $t {
             #[inline]
             #[rustc_inherit_overflow_checks]
             fn mul_assign(&mut self, other: $t) { *self *= other }
         }
 
-        forward_ref_op_assign! { impl MulAssign, mul_assign for $t, $t }
+        forward_ref_op_assign! { impl const MulAssign, mul_assign for $t, $t }
     )+)
 }
 
@@ -919,12 +930,13 @@ pub trait DivAssign<Rhs = Self> {
 macro_rules! div_assign_impl {
     ($($t:ty)+) => ($(
         #[stable(feature = "op_assign_traits", since = "1.8.0")]
-        impl DivAssign for $t {
+        #[rustc_const_unstable(feature = "const_ops", issue = "90080")]
+        impl const DivAssign for $t {
             #[inline]
             fn div_assign(&mut self, other: $t) { *self /= other }
         }
 
-        forward_ref_op_assign! { impl DivAssign, div_assign for $t, $t }
+        forward_ref_op_assign! { impl const DivAssign, div_assign for $t, $t }
     )+)
 }
 
@@ -979,12 +991,13 @@ pub trait RemAssign<Rhs = Self> {
 macro_rules! rem_assign_impl {
     ($($t:ty)+) => ($(
         #[stable(feature = "op_assign_traits", since = "1.8.0")]
-        impl RemAssign for $t {
+        #[rustc_const_unstable(feature = "const_ops", issue = "90080")]
+        impl const RemAssign for $t {
             #[inline]
             fn rem_assign(&mut self, other: $t) { *self %= other }
         }
 
-        forward_ref_op_assign! { impl RemAssign, rem_assign for $t, $t }
+        forward_ref_op_assign! { impl const RemAssign, rem_assign for $t, $t }
     )+)
 }
 
diff --git a/library/core/src/ops/bit.rs b/library/core/src/ops/bit.rs
index 92f45ac9e7e..255f6cb7933 100644
--- a/library/core/src/ops/bit.rs
+++ b/library/core/src/ops/bit.rs
@@ -54,14 +54,15 @@ pub trait Not {
 macro_rules! not_impl {
     ($($t:ty)*) => ($(
         #[stable(feature = "rust1", since = "1.0.0")]
-        impl Not for $t {
+        #[rustc_const_unstable(feature = "const_ops", issue = "90080")]
+        impl const Not for $t {
             type Output = $t;
 
             #[inline]
             fn not(self) -> $t { !self }
         }
 
-        forward_ref_unop! { impl Not, not for $t }
+        forward_ref_unop! { impl const Not, not for $t }
     )*)
 }
 
@@ -154,14 +155,15 @@ pub trait BitAnd<Rhs = Self> {
 macro_rules! bitand_impl {
     ($($t:ty)*) => ($(
         #[stable(feature = "rust1", since = "1.0.0")]
-        impl BitAnd for $t {
+        #[rustc_const_unstable(feature = "const_ops", issue = "90080")]
+        impl const BitAnd for $t {
             type Output = $t;
 
             #[inline]
             fn bitand(self, rhs: $t) -> $t { self & rhs }
         }
 
-        forward_ref_binop! { impl BitAnd, bitand for $t, $t }
+        forward_ref_binop! { impl const BitAnd, bitand for $t, $t }
     )*)
 }
 
@@ -254,14 +256,15 @@ pub trait BitOr<Rhs = Self> {
 macro_rules! bitor_impl {
     ($($t:ty)*) => ($(
         #[stable(feature = "rust1", since = "1.0.0")]
-        impl BitOr for $t {
+        #[rustc_const_unstable(feature = "const_ops", issue = "90080")]
+        impl const BitOr for $t {
             type Output = $t;
 
             #[inline]
             fn bitor(self, rhs: $t) -> $t { self | rhs }
         }
 
-        forward_ref_binop! { impl BitOr, bitor for $t, $t }
+        forward_ref_binop! { impl const BitOr, bitor for $t, $t }
     )*)
 }
 
@@ -354,14 +357,15 @@ pub trait BitXor<Rhs = Self> {
 macro_rules! bitxor_impl {
     ($($t:ty)*) => ($(
         #[stable(feature = "rust1", since = "1.0.0")]
-        impl BitXor for $t {
+        #[rustc_const_unstable(feature = "const_ops", issue = "90080")]
+        impl const BitXor for $t {
             type Output = $t;
 
             #[inline]
             fn bitxor(self, other: $t) -> $t { self ^ other }
         }
 
-        forward_ref_binop! { impl BitXor, bitxor for $t, $t }
+        forward_ref_binop! { impl const BitXor, bitxor for $t, $t }
     )*)
 }
 
@@ -451,7 +455,8 @@ pub trait Shl<Rhs = Self> {
 macro_rules! shl_impl {
     ($t:ty, $f:ty) => {
         #[stable(feature = "rust1", since = "1.0.0")]
-        impl Shl<$f> for $t {
+        #[rustc_const_unstable(feature = "const_ops", issue = "90080")]
+        impl const Shl<$f> for $t {
             type Output = $t;
 
             #[inline]
@@ -461,7 +466,7 @@ macro_rules! shl_impl {
             }
         }
 
-        forward_ref_binop! { impl Shl, shl for $t, $f }
+        forward_ref_binop! { impl const Shl, shl for $t, $f }
     };
 }
 
@@ -569,7 +574,8 @@ pub trait Shr<Rhs = Self> {
 macro_rules! shr_impl {
     ($t:ty, $f:ty) => {
         #[stable(feature = "rust1", since = "1.0.0")]
-        impl Shr<$f> for $t {
+        #[rustc_const_unstable(feature = "const_ops", issue = "90080")]
+        impl const Shr<$f> for $t {
             type Output = $t;
 
             #[inline]
@@ -579,7 +585,7 @@ macro_rules! shr_impl {
             }
         }
 
-        forward_ref_binop! { impl Shr, shr for $t, $f }
+        forward_ref_binop! { impl const Shr, shr for $t, $f }
     };
 }
 
@@ -704,12 +710,13 @@ pub trait BitAndAssign<Rhs = Self> {
 macro_rules! bitand_assign_impl {
     ($($t:ty)+) => ($(
         #[stable(feature = "op_assign_traits", since = "1.8.0")]
-        impl BitAndAssign for $t {
+        #[rustc_const_unstable(feature = "const_ops", issue = "90080")]
+        impl const BitAndAssign for $t {
             #[inline]
             fn bitand_assign(&mut self, other: $t) { *self &= other }
         }
 
-        forward_ref_op_assign! { impl BitAndAssign, bitand_assign for $t, $t }
+        forward_ref_op_assign! { impl const BitAndAssign, bitand_assign for $t, $t }
     )+)
 }
 
@@ -775,12 +782,13 @@ pub trait BitOrAssign<Rhs = Self> {
 macro_rules! bitor_assign_impl {
     ($($t:ty)+) => ($(
         #[stable(feature = "op_assign_traits", since = "1.8.0")]
-        impl BitOrAssign for $t {
+        #[rustc_const_unstable(feature = "const_ops", issue = "90080")]
+        impl const BitOrAssign for $t {
             #[inline]
             fn bitor_assign(&mut self, other: $t) { *self |= other }
         }
 
-        forward_ref_op_assign! { impl BitOrAssign, bitor_assign for $t, $t }
+        forward_ref_op_assign! { impl const BitOrAssign, bitor_assign for $t, $t }
     )+)
 }
 
@@ -846,12 +854,13 @@ pub trait BitXorAssign<Rhs = Self> {
 macro_rules! bitxor_assign_impl {
     ($($t:ty)+) => ($(
         #[stable(feature = "op_assign_traits", since = "1.8.0")]
-        impl BitXorAssign for $t {
+        #[rustc_const_unstable(feature = "const_ops", issue = "90080")]
+        impl const BitXorAssign for $t {
             #[inline]
             fn bitxor_assign(&mut self, other: $t) { *self ^= other }
         }
 
-        forward_ref_op_assign! { impl BitXorAssign, bitxor_assign for $t, $t }
+        forward_ref_op_assign! { impl const BitXorAssign, bitxor_assign for $t, $t }
     )+)
 }
 
@@ -907,7 +916,8 @@ pub trait ShlAssign<Rhs = Self> {
 macro_rules! shl_assign_impl {
     ($t:ty, $f:ty) => {
         #[stable(feature = "op_assign_traits", since = "1.8.0")]
-        impl ShlAssign<$f> for $t {
+        #[rustc_const_unstable(feature = "const_ops", issue = "90080")]
+        impl const ShlAssign<$f> for $t {
             #[inline]
             #[rustc_inherit_overflow_checks]
             fn shl_assign(&mut self, other: $f) {
@@ -915,7 +925,7 @@ macro_rules! shl_assign_impl {
             }
         }
 
-        forward_ref_op_assign! { impl ShlAssign, shl_assign for $t, $f }
+        forward_ref_op_assign! { impl const ShlAssign, shl_assign for $t, $f }
     };
 }
 
@@ -989,7 +999,8 @@ pub trait ShrAssign<Rhs = Self> {
 macro_rules! shr_assign_impl {
     ($t:ty, $f:ty) => {
         #[stable(feature = "op_assign_traits", since = "1.8.0")]
-        impl ShrAssign<$f> for $t {
+        #[rustc_const_unstable(feature = "const_ops", issue = "90080")]
+        impl const ShrAssign<$f> for $t {
             #[inline]
             #[rustc_inherit_overflow_checks]
             fn shr_assign(&mut self, other: $f) {
@@ -997,7 +1008,7 @@ macro_rules! shr_assign_impl {
             }
         }
 
-        forward_ref_op_assign! { impl ShrAssign, shr_assign for $t, $f }
+        forward_ref_op_assign! { impl const ShrAssign, shr_assign for $t, $f }
     };
 }