From 362879d8c13f3912510c5a299dbf6fa2c2067afa Mon Sep 17 00:00:00 2001
From: ltdk <usr@ltdk.xyz>
Date: Mon, 14 Oct 2024 16:05:01 -0400
Subject: [PATCH 1/8] Run most core::num tests in const context too

---
 library/core/tests/lib.rs             |  35 ++
 library/core/tests/num/int_macros.rs  | 606 +++++++++++++-------------
 library/core/tests/num/uint_macros.rs | 423 +++++++++---------
 3 files changed, 539 insertions(+), 525 deletions(-)

diff --git a/library/core/tests/lib.rs b/library/core/tests/lib.rs
index 37e7db1157c89..76ab0d157b61b 100644
--- a/library/core/tests/lib.rs
+++ b/library/core/tests/lib.rs
@@ -16,11 +16,14 @@
 #![feature(clone_to_uninit)]
 #![feature(const_align_of_val_raw)]
 #![feature(const_align_offset)]
+#![feature(const_bigint_helper_methods)]
 #![feature(const_black_box)]
+#![feature(const_eval_select)]
 #![feature(const_hash)]
 #![feature(const_heap)]
 #![feature(const_likely)]
 #![feature(const_nonnull_new)]
+#![feature(const_num_midpoint)]
 #![feature(const_option_ext)]
 #![feature(const_pin)]
 #![feature(const_pointer_is_aligned)]
@@ -45,6 +48,7 @@
 #![feature(get_many_mut)]
 #![feature(hasher_prefixfree_extras)]
 #![feature(hashmap_internals)]
+#![feature(inline_const_pat)]
 #![feature(int_roundings)]
 #![feature(ip)]
 #![feature(ip_from)]
@@ -104,6 +108,37 @@
 #![deny(fuzzy_provenance_casts)]
 #![deny(unsafe_op_in_unsafe_fn)]
 
+/// Version of `assert_matches` that ignores fancy runtime printing in const context and uses structural equality.
+macro_rules! assert_eq_const_safe {
+    ($left:expr, $right:expr$(, $($arg:tt)+)?) => {
+        {
+            fn runtime() {
+                assert_eq!($left, $right, $($arg)*);
+            }
+            const fn compiletime() {
+                assert!(matches!($left, const { $right }));
+            }
+            core::intrinsics::const_eval_select((), compiletime, runtime)
+        }
+    };
+}
+
+/// Creates a test for runtime and a test for constant-time.
+macro_rules! test_runtime_and_compiletime {
+    ($(
+        $(#[$attr:meta])*
+        fn $test:ident() $block:block
+    )*) => {
+        $(
+            $(#[$attr])*
+            #[test]
+            fn $test() $block
+            $(#[$attr])*
+            const _: () = $block;
+        )*
+    }
+}
+
 mod alloc;
 mod any;
 mod array;
diff --git a/library/core/tests/num/int_macros.rs b/library/core/tests/num/int_macros.rs
index 6a26bd15a663d..7d3381ee50446 100644
--- a/library/core/tests/num/int_macros.rs
+++ b/library/core/tests/num/int_macros.rs
@@ -17,42 +17,6 @@ macro_rules! int_module {
             num::test_num(10 as $T, 2 as $T);
         }
 
-        #[test]
-        fn test_rem_euclid() {
-            assert_eq!((-1 as $T).rem_euclid(MIN), MAX);
-        }
-
-        #[test]
-        pub fn test_abs() {
-            assert_eq!((1 as $T).abs(), 1 as $T);
-            assert_eq!((0 as $T).abs(), 0 as $T);
-            assert_eq!((-1 as $T).abs(), 1 as $T);
-        }
-
-        #[test]
-        fn test_signum() {
-            assert_eq!((1 as $T).signum(), 1 as $T);
-            assert_eq!((0 as $T).signum(), 0 as $T);
-            assert_eq!((-0 as $T).signum(), 0 as $T);
-            assert_eq!((-1 as $T).signum(), -1 as $T);
-        }
-
-        #[test]
-        fn test_is_positive() {
-            assert!((1 as $T).is_positive());
-            assert!(!(0 as $T).is_positive());
-            assert!(!(-0 as $T).is_positive());
-            assert!(!(-1 as $T).is_positive());
-        }
-
-        #[test]
-        fn test_is_negative() {
-            assert!(!(1 as $T).is_negative());
-            assert!(!(0 as $T).is_negative());
-            assert!(!(-0 as $T).is_negative());
-            assert!((-1 as $T).is_negative());
-        }
-
         #[test]
         fn test_bitwise_operators() {
             assert_eq!(0b1110 as $T, (0b1100 as $T).bitor(0b1010 as $T));
@@ -63,6 +27,40 @@ macro_rules! int_module {
             assert_eq!(-(0b11 as $T) - (1 as $T), (0b11 as $T).not());
         }
 
+        test_runtime_and_compiletime! {
+
+            fn test_rem_euclid() {
+                assert_eq_const_safe!((-1 as $T).rem_euclid(MIN), MAX);
+            }
+
+            fn test_abs() {
+                assert_eq_const_safe!((1 as $T).abs(), 1 as $T);
+                assert_eq_const_safe!((0 as $T).abs(), 0 as $T);
+                assert_eq_const_safe!((-1 as $T).abs(), 1 as $T);
+            }
+
+            fn test_signum() {
+                assert_eq_const_safe!((1 as $T).signum(), 1 as $T);
+                assert_eq_const_safe!((0 as $T).signum(), 0 as $T);
+                assert_eq_const_safe!((-0 as $T).signum(), 0 as $T);
+                assert_eq_const_safe!((-1 as $T).signum(), -1 as $T);
+            }
+
+            fn test_is_positive() {
+                assert!((1 as $T).is_positive());
+                assert!(!(0 as $T).is_positive());
+                assert!(!(-0 as $T).is_positive());
+                assert!(!(-1 as $T).is_positive());
+            }
+
+            fn test_is_negative() {
+                assert!(!(1 as $T).is_negative());
+                assert!(!(0 as $T).is_negative());
+                assert!(!(-0 as $T).is_negative());
+                assert!((-1 as $T).is_negative());
+            }
+        }
+
         const A: $T = 0b0101100;
         const B: $T = 0b0100001;
         const C: $T = 0b1111001;
@@ -70,134 +68,126 @@ macro_rules! int_module {
         const _0: $T = 0;
         const _1: $T = !0;
 
-        #[test]
-        fn test_count_ones() {
-            assert_eq!(A.count_ones(), 3);
-            assert_eq!(B.count_ones(), 2);
-            assert_eq!(C.count_ones(), 5);
-        }
+        test_runtime_and_compiletime! {
+            fn test_count_ones() {
+                assert_eq_const_safe!(A.count_ones(), 3);
+                assert_eq_const_safe!(B.count_ones(), 2);
+                assert_eq_const_safe!(C.count_ones(), 5);
+            }
 
-        #[test]
-        fn test_count_zeros() {
-            assert_eq!(A.count_zeros(), $T::BITS - 3);
-            assert_eq!(B.count_zeros(), $T::BITS - 2);
-            assert_eq!(C.count_zeros(), $T::BITS - 5);
-        }
+            fn test_count_zeros() {
+                assert_eq_const_safe!(A.count_zeros(), $T::BITS - 3);
+                assert_eq_const_safe!(B.count_zeros(), $T::BITS - 2);
+                assert_eq_const_safe!(C.count_zeros(), $T::BITS - 5);
+            }
 
-        #[test]
-        fn test_leading_trailing_ones() {
-            let a: $T = 0b0101_1111;
-            assert_eq!(a.trailing_ones(), 5);
-            assert_eq!((!a).leading_ones(), $T::BITS - 7);
+            fn test_leading_trailing_ones() {
+                const A: $T = 0b0101_1111;
+                assert_eq_const_safe!(A.trailing_ones(), 5);
+                assert_eq_const_safe!((!A).leading_ones(), $T::BITS - 7);
 
-            assert_eq!(a.reverse_bits().leading_ones(), 5);
+                assert_eq_const_safe!(A.reverse_bits().leading_ones(), 5);
 
-            assert_eq!(_1.leading_ones(), $T::BITS);
-            assert_eq!(_1.trailing_ones(), $T::BITS);
+                assert_eq_const_safe!(_1.leading_ones(), $T::BITS);
+                assert_eq_const_safe!(_1.trailing_ones(), $T::BITS);
 
-            assert_eq!((_1 << 1).trailing_ones(), 0);
-            assert_eq!(MAX.leading_ones(), 0);
+                assert_eq_const_safe!((_1 << 1).trailing_ones(), 0);
+                assert_eq_const_safe!(MAX.leading_ones(), 0);
 
-            assert_eq!((_1 << 1).leading_ones(), $T::BITS - 1);
-            assert_eq!(MAX.trailing_ones(), $T::BITS - 1);
+                assert_eq_const_safe!((_1 << 1).leading_ones(), $T::BITS - 1);
+                assert_eq_const_safe!(MAX.trailing_ones(), $T::BITS - 1);
 
-            assert_eq!(_0.leading_ones(), 0);
-            assert_eq!(_0.trailing_ones(), 0);
+                assert_eq_const_safe!(_0.leading_ones(), 0);
+                assert_eq_const_safe!(_0.trailing_ones(), 0);
 
-            let x: $T = 0b0010_1100;
-            assert_eq!(x.leading_ones(), 0);
-            assert_eq!(x.trailing_ones(), 0);
-        }
+                const X: $T = 0b0010_1100;
+                assert_eq_const_safe!(X.leading_ones(), 0);
+                assert_eq_const_safe!(X.trailing_ones(), 0);
+            }
 
-        #[test]
-        fn test_rotate() {
-            assert_eq!(A.rotate_left(6).rotate_right(2).rotate_right(4), A);
-            assert_eq!(B.rotate_left(3).rotate_left(2).rotate_right(5), B);
-            assert_eq!(C.rotate_left(6).rotate_right(2).rotate_right(4), C);
-
-            // Rotating these should make no difference
-            //
-            // We test using 124 bits because to ensure that overlong bit shifts do
-            // not cause undefined behaviour. See #10183.
-            assert_eq!(_0.rotate_left(124), _0);
-            assert_eq!(_1.rotate_left(124), _1);
-            assert_eq!(_0.rotate_right(124), _0);
-            assert_eq!(_1.rotate_right(124), _1);
-
-            // Rotating by 0 should have no effect
-            assert_eq!(A.rotate_left(0), A);
-            assert_eq!(B.rotate_left(0), B);
-            assert_eq!(C.rotate_left(0), C);
-            // Rotating by a multiple of word size should also have no effect
-            assert_eq!(A.rotate_left(128), A);
-            assert_eq!(B.rotate_left(128), B);
-            assert_eq!(C.rotate_left(128), C);
-        }
+            fn test_rotate() {
+                assert_eq_const_safe!(A.rotate_left(6).rotate_right(2).rotate_right(4), A);
+                assert_eq_const_safe!(B.rotate_left(3).rotate_left(2).rotate_right(5), B);
+                assert_eq_const_safe!(C.rotate_left(6).rotate_right(2).rotate_right(4), C);
+
+                // Rotating these should make no difference
+                //
+                // We test using 124 bits because to ensure that overlong bit shifts do
+                // not cause undefined behaviour. See #10183.
+                assert_eq_const_safe!(_0.rotate_left(124), _0);
+                assert_eq_const_safe!(_1.rotate_left(124), _1);
+                assert_eq_const_safe!(_0.rotate_right(124), _0);
+                assert_eq_const_safe!(_1.rotate_right(124), _1);
+
+                // Rotating by 0 should have no effect
+                assert_eq_const_safe!(A.rotate_left(0), A);
+                assert_eq_const_safe!(B.rotate_left(0), B);
+                assert_eq_const_safe!(C.rotate_left(0), C);
+                // Rotating by a multiple of word size should also have no effect
+                assert_eq_const_safe!(A.rotate_left(128), A);
+                assert_eq_const_safe!(B.rotate_left(128), B);
+                assert_eq_const_safe!(C.rotate_left(128), C);
+            }
 
-        #[test]
-        fn test_swap_bytes() {
-            assert_eq!(A.swap_bytes().swap_bytes(), A);
-            assert_eq!(B.swap_bytes().swap_bytes(), B);
-            assert_eq!(C.swap_bytes().swap_bytes(), C);
-
-            // Swapping these should make no difference
-            assert_eq!(_0.swap_bytes(), _0);
-            assert_eq!(_1.swap_bytes(), _1);
-        }
+            fn test_swap_bytes() {
+                assert_eq_const_safe!(A.swap_bytes().swap_bytes(), A);
+                assert_eq_const_safe!(B.swap_bytes().swap_bytes(), B);
+                assert_eq_const_safe!(C.swap_bytes().swap_bytes(), C);
 
-        #[test]
-        fn test_le() {
-            assert_eq!($T::from_le(A.to_le()), A);
-            assert_eq!($T::from_le(B.to_le()), B);
-            assert_eq!($T::from_le(C.to_le()), C);
-            assert_eq!($T::from_le(_0), _0);
-            assert_eq!($T::from_le(_1), _1);
-            assert_eq!(_0.to_le(), _0);
-            assert_eq!(_1.to_le(), _1);
-        }
+                // Swapping these should make no difference
+                assert_eq_const_safe!(_0.swap_bytes(), _0);
+                assert_eq_const_safe!(_1.swap_bytes(), _1);
+            }
 
-        #[test]
-        fn test_be() {
-            assert_eq!($T::from_be(A.to_be()), A);
-            assert_eq!($T::from_be(B.to_be()), B);
-            assert_eq!($T::from_be(C.to_be()), C);
-            assert_eq!($T::from_be(_0), _0);
-            assert_eq!($T::from_be(_1), _1);
-            assert_eq!(_0.to_be(), _0);
-            assert_eq!(_1.to_be(), _1);
-        }
+            fn test_le() {
+                assert_eq_const_safe!($T::from_le(A.to_le()), A);
+                assert_eq_const_safe!($T::from_le(B.to_le()), B);
+                assert_eq_const_safe!($T::from_le(C.to_le()), C);
+                assert_eq_const_safe!($T::from_le(_0), _0);
+                assert_eq_const_safe!($T::from_le(_1), _1);
+                assert_eq_const_safe!(_0.to_le(), _0);
+                assert_eq_const_safe!(_1.to_le(), _1);
+            }
 
-        #[test]
-        fn test_signed_checked_div() {
-            assert_eq!((10 as $T).checked_div(2), Some(5));
-            assert_eq!((5 as $T).checked_div(0), None);
-            assert_eq!(isize::MIN.checked_div(-1), None);
-        }
+            fn test_be() {
+                assert_eq_const_safe!($T::from_be(A.to_be()), A);
+                assert_eq_const_safe!($T::from_be(B.to_be()), B);
+                assert_eq_const_safe!($T::from_be(C.to_be()), C);
+                assert_eq_const_safe!($T::from_be(_0), _0);
+                assert_eq_const_safe!($T::from_be(_1), _1);
+                assert_eq_const_safe!(_0.to_be(), _0);
+                assert_eq_const_safe!(_1.to_be(), _1);
+            }
 
-        #[test]
-        fn test_saturating_abs() {
-            assert_eq!((0 as $T).saturating_abs(), 0);
-            assert_eq!((123 as $T).saturating_abs(), 123);
-            assert_eq!((-123 as $T).saturating_abs(), 123);
-            assert_eq!((MAX - 2).saturating_abs(), MAX - 2);
-            assert_eq!((MAX - 1).saturating_abs(), MAX - 1);
-            assert_eq!(MAX.saturating_abs(), MAX);
-            assert_eq!((MIN + 2).saturating_abs(), MAX - 1);
-            assert_eq!((MIN + 1).saturating_abs(), MAX);
-            assert_eq!(MIN.saturating_abs(), MAX);
-        }
+            fn test_signed_checked_div() {
+                assert_eq_const_safe!((10 as $T).checked_div(2), Some(5));
+                assert_eq_const_safe!((5 as $T).checked_div(0), None);
+                assert_eq_const_safe!(isize::MIN.checked_div(-1), None);
+            }
 
-        #[test]
-        fn test_saturating_neg() {
-            assert_eq!((0 as $T).saturating_neg(), 0);
-            assert_eq!((123 as $T).saturating_neg(), -123);
-            assert_eq!((-123 as $T).saturating_neg(), 123);
-            assert_eq!((MAX - 2).saturating_neg(), MIN + 3);
-            assert_eq!((MAX - 1).saturating_neg(), MIN + 2);
-            assert_eq!(MAX.saturating_neg(), MIN + 1);
-            assert_eq!((MIN + 2).saturating_neg(), MAX - 1);
-            assert_eq!((MIN + 1).saturating_neg(), MAX);
-            assert_eq!(MIN.saturating_neg(), MAX);
+            fn test_saturating_abs() {
+                assert_eq_const_safe!((0 as $T).saturating_abs(), 0);
+                assert_eq_const_safe!((123 as $T).saturating_abs(), 123);
+                assert_eq_const_safe!((-123 as $T).saturating_abs(), 123);
+                assert_eq_const_safe!((MAX - 2).saturating_abs(), MAX - 2);
+                assert_eq_const_safe!((MAX - 1).saturating_abs(), MAX - 1);
+                assert_eq_const_safe!(MAX.saturating_abs(), MAX);
+                assert_eq_const_safe!((MIN + 2).saturating_abs(), MAX - 1);
+                assert_eq_const_safe!((MIN + 1).saturating_abs(), MAX);
+                assert_eq_const_safe!(MIN.saturating_abs(), MAX);
+            }
+
+            fn test_saturating_neg() {
+                assert_eq_const_safe!((0 as $T).saturating_neg(), 0);
+                assert_eq_const_safe!((123 as $T).saturating_neg(), -123);
+                assert_eq_const_safe!((-123 as $T).saturating_neg(), 123);
+                assert_eq_const_safe!((MAX - 2).saturating_neg(), MIN + 3);
+                assert_eq_const_safe!((MAX - 1).saturating_neg(), MIN + 2);
+                assert_eq_const_safe!(MAX.saturating_neg(), MIN + 1);
+                assert_eq_const_safe!((MIN + 2).saturating_neg(), MAX - 1);
+                assert_eq_const_safe!((MIN + 1).saturating_neg(), MAX);
+                assert_eq_const_safe!(MIN.saturating_neg(), MAX);
+            }
         }
 
         #[test]
@@ -222,173 +212,173 @@ macro_rules! int_module {
             assert_eq!(from_str::<$T>("x"), None);
         }
 
-        #[test]
-        fn test_from_str_radix() {
-            assert_eq!($T::from_str_radix("123", 10), Ok(123 as $T));
-            assert_eq!($T::from_str_radix("1001", 2), Ok(9 as $T));
-            assert_eq!($T::from_str_radix("123", 8), Ok(83 as $T));
-            assert_eq!(i32::from_str_radix("123", 16), Ok(291 as i32));
-            assert_eq!(i32::from_str_radix("ffff", 16), Ok(65535 as i32));
-            assert_eq!(i32::from_str_radix("FFFF", 16), Ok(65535 as i32));
-            assert_eq!($T::from_str_radix("z", 36), Ok(35 as $T));
-            assert_eq!($T::from_str_radix("Z", 36), Ok(35 as $T));
-
-            assert_eq!($T::from_str_radix("-123", 10), Ok(-123 as $T));
-            assert_eq!($T::from_str_radix("-1001", 2), Ok(-9 as $T));
-            assert_eq!($T::from_str_radix("-123", 8), Ok(-83 as $T));
-            assert_eq!(i32::from_str_radix("-123", 16), Ok(-291 as i32));
-            assert_eq!(i32::from_str_radix("-ffff", 16), Ok(-65535 as i32));
-            assert_eq!(i32::from_str_radix("-FFFF", 16), Ok(-65535 as i32));
-            assert_eq!($T::from_str_radix("-z", 36), Ok(-35 as $T));
-            assert_eq!($T::from_str_radix("-Z", 36), Ok(-35 as $T));
-
-            assert_eq!($T::from_str_radix("Z", 35).ok(), None::<$T>);
-            assert_eq!($T::from_str_radix("-9", 2).ok(), None::<$T>);
-            assert_eq!($T::from_str_radix("10_0", 10).ok(), None::<$T>);
-            assert_eq!(u32::from_str_radix("-9", 10).ok(), None::<u32>);
-        }
+        test_runtime_and_compiletime! {
+            fn test_from_str_radix() {
+                assert_eq_const_safe!($T::from_str_radix("123", 10), Ok(123 as $T));
+                assert_eq_const_safe!($T::from_str_radix("1001", 2), Ok(9 as $T));
+                assert_eq_const_safe!($T::from_str_radix("123", 8), Ok(83 as $T));
+                assert_eq_const_safe!(i32::from_str_radix("123", 16), Ok(291 as i32));
+                assert_eq_const_safe!(i32::from_str_radix("ffff", 16), Ok(65535 as i32));
+                assert_eq_const_safe!(i32::from_str_radix("FFFF", 16), Ok(65535 as i32));
+                assert_eq_const_safe!($T::from_str_radix("z", 36), Ok(35 as $T));
+                assert_eq_const_safe!($T::from_str_radix("Z", 36), Ok(35 as $T));
+
+                assert_eq_const_safe!($T::from_str_radix("-123", 10), Ok(-123 as $T));
+                assert_eq_const_safe!($T::from_str_radix("-1001", 2), Ok(-9 as $T));
+                assert_eq_const_safe!($T::from_str_radix("-123", 8), Ok(-83 as $T));
+                assert_eq_const_safe!(i32::from_str_radix("-123", 16), Ok(-291 as i32));
+                assert_eq_const_safe!(i32::from_str_radix("-ffff", 16), Ok(-65535 as i32));
+                assert_eq_const_safe!(i32::from_str_radix("-FFFF", 16), Ok(-65535 as i32));
+                assert_eq_const_safe!($T::from_str_radix("-z", 36), Ok(-35 as $T));
+                assert_eq_const_safe!($T::from_str_radix("-Z", 36), Ok(-35 as $T));
+
+                assert!($T::from_str_radix("Z", 35).is_err());
+                assert!($T::from_str_radix("-9", 2).is_err());
+                assert!($T::from_str_radix("10_0", 10).is_err());
+                assert!(u32::from_str_radix("-9", 10).is_err());
+            }
 
-        #[test]
-        fn test_pow() {
-            let mut r = 2 as $T;
-            assert_eq!(r.pow(2), 4 as $T);
-            assert_eq!(r.pow(0), 1 as $T);
-            assert_eq!(r.wrapping_pow(2), 4 as $T);
-            assert_eq!(r.wrapping_pow(0), 1 as $T);
-            assert_eq!(r.checked_pow(2), Some(4 as $T));
-            assert_eq!(r.checked_pow(0), Some(1 as $T));
-            assert_eq!(r.overflowing_pow(2), (4 as $T, false));
-            assert_eq!(r.overflowing_pow(0), (1 as $T, false));
-            assert_eq!(r.saturating_pow(2), 4 as $T);
-            assert_eq!(r.saturating_pow(0), 1 as $T);
-
-            r = MAX;
-            // use `^` to represent .pow() with no overflow.
-            // if itest::MAX == 2^j-1, then itest is a `j` bit int,
-            // so that `itest::MAX*itest::MAX == 2^(2*j)-2^(j+1)+1`,
-            // thussaturating_pow the overflowing result is exactly 1.
-            assert_eq!(r.wrapping_pow(2), 1 as $T);
-            assert_eq!(r.checked_pow(2), None);
-            assert_eq!(r.overflowing_pow(2), (1 as $T, true));
-            assert_eq!(r.saturating_pow(2), MAX);
-            //test for negative exponent.
-            r = -2 as $T;
-            assert_eq!(r.pow(2), 4 as $T);
-            assert_eq!(r.pow(3), -8 as $T);
-            assert_eq!(r.pow(0), 1 as $T);
-            assert_eq!(r.wrapping_pow(2), 4 as $T);
-            assert_eq!(r.wrapping_pow(3), -8 as $T);
-            assert_eq!(r.wrapping_pow(0), 1 as $T);
-            assert_eq!(r.checked_pow(2), Some(4 as $T));
-            assert_eq!(r.checked_pow(3), Some(-8 as $T));
-            assert_eq!(r.checked_pow(0), Some(1 as $T));
-            assert_eq!(r.overflowing_pow(2), (4 as $T, false));
-            assert_eq!(r.overflowing_pow(3), (-8 as $T, false));
-            assert_eq!(r.overflowing_pow(0), (1 as $T, false));
-            assert_eq!(r.saturating_pow(2), 4 as $T);
-            assert_eq!(r.saturating_pow(3), -8 as $T);
-            assert_eq!(r.saturating_pow(0), 1 as $T);
-        }
+            fn test_pow() {
+                {
+                    const R: $T = 2;
+                    assert_eq_const_safe!(R.pow(2), 4 as $T);
+                    assert_eq_const_safe!(R.pow(0), 1 as $T);
+                    assert_eq_const_safe!(R.wrapping_pow(2), 4 as $T);
+                    assert_eq_const_safe!(R.wrapping_pow(0), 1 as $T);
+                    assert_eq_const_safe!(R.checked_pow(2), Some(4 as $T));
+                    assert_eq_const_safe!(R.checked_pow(0), Some(1 as $T));
+                    assert_eq_const_safe!(R.overflowing_pow(2), (4 as $T, false));
+                    assert_eq_const_safe!(R.overflowing_pow(0), (1 as $T, false));
+                    assert_eq_const_safe!(R.saturating_pow(2), 4 as $T);
+                    assert_eq_const_safe!(R.saturating_pow(0), 1 as $T);
+                }
+
+                {
+                    const R: $T = MAX;
+                    // use `^` to represent .pow() with no overflow.
+                    // if itest::MAX == 2^j-1, then itest is a `j` bit int,
+                    // so that `itest::MAX*itest::MAX == 2^(2*j)-2^(j+1)+1`,
+                    // thussaturating_pow the overflowing result is exactly 1.
+                    assert_eq_const_safe!(R.wrapping_pow(2), 1 as $T);
+                    assert_eq_const_safe!(R.checked_pow(2), None);
+                    assert_eq_const_safe!(R.overflowing_pow(2), (1 as $T, true));
+                    assert_eq_const_safe!(R.saturating_pow(2), MAX);
+                }
+
+                {
+                    // test for negative exponent.
+                    const R: $T = -2;
+                    assert_eq_const_safe!(R.pow(2), 4 as $T);
+                    assert_eq_const_safe!(R.pow(3), -8 as $T);
+                    assert_eq_const_safe!(R.pow(0), 1 as $T);
+                    assert_eq_const_safe!(R.wrapping_pow(2), 4 as $T);
+                    assert_eq_const_safe!(R.wrapping_pow(3), -8 as $T);
+                    assert_eq_const_safe!(R.wrapping_pow(0), 1 as $T);
+                    assert_eq_const_safe!(R.checked_pow(2), Some(4 as $T));
+                    assert_eq_const_safe!(R.checked_pow(3), Some(-8 as $T));
+                    assert_eq_const_safe!(R.checked_pow(0), Some(1 as $T));
+                    assert_eq_const_safe!(R.overflowing_pow(2), (4 as $T, false));
+                    assert_eq_const_safe!(R.overflowing_pow(3), (-8 as $T, false));
+                    assert_eq_const_safe!(R.overflowing_pow(0), (1 as $T, false));
+                    assert_eq_const_safe!(R.saturating_pow(2), 4 as $T);
+                    assert_eq_const_safe!(R.saturating_pow(3), -8 as $T);
+                    assert_eq_const_safe!(R.saturating_pow(0), 1 as $T);
+                }
+            }
 
-        #[test]
-        fn test_div_floor() {
-            let a: $T = 8;
-            let b = 3;
-            assert_eq!(a.div_floor(b), 2);
-            assert_eq!(a.div_floor(-b), -3);
-            assert_eq!((-a).div_floor(b), -3);
-            assert_eq!((-a).div_floor(-b), 2);
-        }
+            fn test_div_floor() {
+                const A: $T = 8;
+                const B: $T = 3;
+                assert_eq_const_safe!(A.div_floor(B), 2);
+                assert_eq_const_safe!(A.div_floor(-B), -3);
+                assert_eq_const_safe!((-A).div_floor(B), -3);
+                assert_eq_const_safe!((-A).div_floor(-B), 2);
+            }
 
-        #[test]
-        fn test_div_ceil() {
-            let a: $T = 8;
-            let b = 3;
-            assert_eq!(a.div_ceil(b), 3);
-            assert_eq!(a.div_ceil(-b), -2);
-            assert_eq!((-a).div_ceil(b), -2);
-            assert_eq!((-a).div_ceil(-b), 3);
-        }
+            fn test_div_ceil() {
+                const A: $T = 8;
+                const B: $T = 3;
+                assert_eq_const_safe!(A.div_ceil(B), 3);
+                assert_eq_const_safe!(A.div_ceil(-B), -2);
+                assert_eq_const_safe!((-A).div_ceil(B), -2);
+                assert_eq_const_safe!((-A).div_ceil(-B), 3);
+            }
 
-        #[test]
-        fn test_next_multiple_of() {
-            assert_eq!((16 as $T).next_multiple_of(8), 16);
-            assert_eq!((23 as $T).next_multiple_of(8), 24);
-            assert_eq!((16 as $T).next_multiple_of(-8), 16);
-            assert_eq!((23 as $T).next_multiple_of(-8), 16);
-            assert_eq!((-16 as $T).next_multiple_of(8), -16);
-            assert_eq!((-23 as $T).next_multiple_of(8), -16);
-            assert_eq!((-16 as $T).next_multiple_of(-8), -16);
-            assert_eq!((-23 as $T).next_multiple_of(-8), -24);
-            assert_eq!(MIN.next_multiple_of(-1), MIN);
-        }
+            fn test_next_multiple_of() {
+                assert_eq_const_safe!((16 as $T).next_multiple_of(8), 16);
+                assert_eq_const_safe!((23 as $T).next_multiple_of(8), 24);
+                assert_eq_const_safe!((16 as $T).next_multiple_of(-8), 16);
+                assert_eq_const_safe!((23 as $T).next_multiple_of(-8), 16);
+                assert_eq_const_safe!((-16 as $T).next_multiple_of(8), -16);
+                assert_eq_const_safe!((-23 as $T).next_multiple_of(8), -16);
+                assert_eq_const_safe!((-16 as $T).next_multiple_of(-8), -16);
+                assert_eq_const_safe!((-23 as $T).next_multiple_of(-8), -24);
+                assert_eq_const_safe!(MIN.next_multiple_of(-1), MIN);
+            }
 
-        #[test]
-        fn test_checked_next_multiple_of() {
-            assert_eq!((16 as $T).checked_next_multiple_of(8), Some(16));
-            assert_eq!((23 as $T).checked_next_multiple_of(8), Some(24));
-            assert_eq!((16 as $T).checked_next_multiple_of(-8), Some(16));
-            assert_eq!((23 as $T).checked_next_multiple_of(-8), Some(16));
-            assert_eq!((-16 as $T).checked_next_multiple_of(8), Some(-16));
-            assert_eq!((-23 as $T).checked_next_multiple_of(8), Some(-16));
-            assert_eq!((-16 as $T).checked_next_multiple_of(-8), Some(-16));
-            assert_eq!((-23 as $T).checked_next_multiple_of(-8), Some(-24));
-            assert_eq!((1 as $T).checked_next_multiple_of(0), None);
-            assert_eq!(MAX.checked_next_multiple_of(2), None);
-            assert_eq!(MIN.checked_next_multiple_of(-3), None);
-            assert_eq!(MIN.checked_next_multiple_of(-1), Some(MIN));
-        }
+            fn test_checked_next_multiple_of() {
+                assert_eq_const_safe!((16 as $T).checked_next_multiple_of(8), Some(16));
+                assert_eq_const_safe!((23 as $T).checked_next_multiple_of(8), Some(24));
+                assert_eq_const_safe!((16 as $T).checked_next_multiple_of(-8), Some(16));
+                assert_eq_const_safe!((23 as $T).checked_next_multiple_of(-8), Some(16));
+                assert_eq_const_safe!((-16 as $T).checked_next_multiple_of(8), Some(-16));
+                assert_eq_const_safe!((-23 as $T).checked_next_multiple_of(8), Some(-16));
+                assert_eq_const_safe!((-16 as $T).checked_next_multiple_of(-8), Some(-16));
+                assert_eq_const_safe!((-23 as $T).checked_next_multiple_of(-8), Some(-24));
+                assert_eq_const_safe!((1 as $T).checked_next_multiple_of(0), None);
+                assert_eq_const_safe!(MAX.checked_next_multiple_of(2), None);
+                assert_eq_const_safe!(MIN.checked_next_multiple_of(-3), None);
+                assert_eq_const_safe!(MIN.checked_next_multiple_of(-1), Some(MIN));
+            }
 
-        #[test]
-        fn test_carrying_add() {
-            assert_eq!($T::MAX.carrying_add(1, false), ($T::MIN, true));
-            assert_eq!($T::MAX.carrying_add(0, true), ($T::MIN, true));
-            assert_eq!($T::MAX.carrying_add(1, true), ($T::MIN + 1, true));
-            assert_eq!($T::MAX.carrying_add(-1, false), ($T::MAX - 1, false));
-            assert_eq!($T::MAX.carrying_add(-1, true), ($T::MAX, false)); // no intermediate overflow
-            assert_eq!($T::MIN.carrying_add(-1, false), ($T::MAX, true));
-            assert_eq!($T::MIN.carrying_add(-1, true), ($T::MIN, false)); // no intermediate overflow
-            assert_eq!((0 as $T).carrying_add($T::MAX, true), ($T::MIN, true));
-            assert_eq!((0 as $T).carrying_add($T::MIN, true), ($T::MIN + 1, false));
-        }
+            fn test_carrying_add() {
+                assert_eq_const_safe!(MAX.carrying_add(1, false), (MIN, true));
+                assert_eq_const_safe!(MAX.carrying_add(0, true), (MIN, true));
+                assert_eq_const_safe!(MAX.carrying_add(1, true), (MIN + 1, true));
+                assert_eq_const_safe!(MAX.carrying_add(-1, false), (MAX - 1, false));
+                assert_eq_const_safe!(MAX.carrying_add(-1, true), (MAX, false)); // no intermediate overflow
+                assert_eq_const_safe!(MIN.carrying_add(-1, false), (MAX, true));
+                assert_eq_const_safe!(MIN.carrying_add(-1, true), (MIN, false)); // no intermediate overflow
+                assert_eq_const_safe!((0 as $T).carrying_add(MAX, true), (MIN, true));
+                assert_eq_const_safe!((0 as $T).carrying_add(MIN, true), (MIN + 1, false));
+            }
 
-        #[test]
-        fn test_borrowing_sub() {
-            assert_eq!($T::MIN.borrowing_sub(1, false), ($T::MAX, true));
-            assert_eq!($T::MIN.borrowing_sub(0, true), ($T::MAX, true));
-            assert_eq!($T::MIN.borrowing_sub(1, true), ($T::MAX - 1, true));
-            assert_eq!($T::MIN.borrowing_sub(-1, false), ($T::MIN + 1, false));
-            assert_eq!($T::MIN.borrowing_sub(-1, true), ($T::MIN, false)); // no intermediate overflow
-            assert_eq!($T::MAX.borrowing_sub(-1, false), ($T::MIN, true));
-            assert_eq!($T::MAX.borrowing_sub(-1, true), ($T::MAX, false)); // no intermediate overflow
-            assert_eq!((0 as $T).borrowing_sub($T::MIN, false), ($T::MIN, true));
-            assert_eq!((0 as $T).borrowing_sub($T::MIN, true), ($T::MAX, false));
-        }
+            fn test_borrowing_sub() {
+                assert_eq_const_safe!(MIN.borrowing_sub(1, false), (MAX, true));
+                assert_eq_const_safe!(MIN.borrowing_sub(0, true), (MAX, true));
+                assert_eq_const_safe!(MIN.borrowing_sub(1, true), (MAX - 1, true));
+                assert_eq_const_safe!(MIN.borrowing_sub(-1, false), (MIN + 1, false));
+                assert_eq_const_safe!(MIN.borrowing_sub(-1, true), (MIN, false)); // no intermediate overflow
+                assert_eq_const_safe!(MAX.borrowing_sub(-1, false), (MIN, true));
+                assert_eq_const_safe!(MAX.borrowing_sub(-1, true), (MAX, false)); // no intermediate overflow
+                assert_eq_const_safe!((0 as $T).borrowing_sub(MIN, false), (MIN, true));
+                assert_eq_const_safe!((0 as $T).borrowing_sub(MIN, true), (MAX, false));
+            }
 
-        #[test]
-        fn test_midpoint() {
-            assert_eq!(<$T>::midpoint(1, 3), 2);
-            assert_eq!(<$T>::midpoint(3, 1), 2);
-
-            assert_eq!(<$T>::midpoint(0, 0), 0);
-            assert_eq!(<$T>::midpoint(0, 2), 1);
-            assert_eq!(<$T>::midpoint(2, 0), 1);
-            assert_eq!(<$T>::midpoint(2, 2), 2);
-
-            assert_eq!(<$T>::midpoint(1, 4), 2);
-            assert_eq!(<$T>::midpoint(4, 1), 2);
-            assert_eq!(<$T>::midpoint(3, 4), 3);
-            assert_eq!(<$T>::midpoint(4, 3), 3);
-
-            assert_eq!(<$T>::midpoint(<$T>::MIN, <$T>::MAX), -1);
-            assert_eq!(<$T>::midpoint(<$T>::MAX, <$T>::MIN), -1);
-            assert_eq!(<$T>::midpoint(<$T>::MIN, <$T>::MIN), <$T>::MIN);
-            assert_eq!(<$T>::midpoint(<$T>::MAX, <$T>::MAX), <$T>::MAX);
-
-            assert_eq!(<$T>::midpoint(<$T>::MIN, 6), <$T>::MIN / 2 + 3);
-            assert_eq!(<$T>::midpoint(6, <$T>::MIN), <$T>::MIN / 2 + 3);
-            assert_eq!(<$T>::midpoint(<$T>::MAX, 6), <$T>::MAX / 2 + 3);
-            assert_eq!(<$T>::midpoint(6, <$T>::MAX), <$T>::MAX / 2 + 3);
+            fn test_midpoint() {
+                assert_eq_const_safe!(<$T>::midpoint(1, 3), 2);
+                assert_eq_const_safe!(<$T>::midpoint(3, 1), 2);
+
+                assert_eq_const_safe!(<$T>::midpoint(0, 0), 0);
+                assert_eq_const_safe!(<$T>::midpoint(0, 2), 1);
+                assert_eq_const_safe!(<$T>::midpoint(2, 0), 1);
+                assert_eq_const_safe!(<$T>::midpoint(2, 2), 2);
+
+                assert_eq_const_safe!(<$T>::midpoint(1, 4), 2);
+                assert_eq_const_safe!(<$T>::midpoint(4, 1), 2);
+                assert_eq_const_safe!(<$T>::midpoint(3, 4), 3);
+                assert_eq_const_safe!(<$T>::midpoint(4, 3), 3);
+
+                assert_eq_const_safe!(<$T>::midpoint(<$T>::MIN, <$T>::MAX), -1);
+                assert_eq_const_safe!(<$T>::midpoint(<$T>::MAX, <$T>::MIN), -1);
+                assert_eq_const_safe!(<$T>::midpoint(<$T>::MIN, <$T>::MIN), <$T>::MIN);
+                assert_eq_const_safe!(<$T>::midpoint(<$T>::MAX, <$T>::MAX), <$T>::MAX);
+
+                assert_eq_const_safe!(<$T>::midpoint(<$T>::MIN, 6), <$T>::MIN / 2 + 3);
+                assert_eq_const_safe!(<$T>::midpoint(6, <$T>::MIN), <$T>::MIN / 2 + 3);
+                assert_eq_const_safe!(<$T>::midpoint(<$T>::MAX, 6), <$T>::MAX / 2 + 3);
+                assert_eq_const_safe!(<$T>::midpoint(6, <$T>::MAX), <$T>::MAX / 2 + 3);
+            }
         }
     };
 }
diff --git a/library/core/tests/num/uint_macros.rs b/library/core/tests/num/uint_macros.rs
index f4fa789461eb8..105aad4522d74 100644
--- a/library/core/tests/num/uint_macros.rs
+++ b/library/core/tests/num/uint_macros.rs
@@ -2,7 +2,6 @@ macro_rules! uint_module {
     ($T:ident) => {
         use core::ops::{BitAnd, BitOr, BitXor, Not, Shl, Shr};
         use core::$T::*;
-        use std::str::FromStr;
 
         use crate::num;
 
@@ -35,122 +34,115 @@ macro_rules! uint_module {
         const _0: $T = 0;
         const _1: $T = !0;
 
-        #[test]
-        fn test_count_ones() {
-            assert!(A.count_ones() == 3);
-            assert!(B.count_ones() == 2);
-            assert!(C.count_ones() == 5);
-        }
+        test_runtime_and_compiletime! {
+            fn test_count_ones() {
+                assert!(A.count_ones() == 3);
+                assert!(B.count_ones() == 2);
+                assert!(C.count_ones() == 5);
+            }
 
-        #[test]
-        fn test_count_zeros() {
-            assert!(A.count_zeros() == $T::BITS - 3);
-            assert!(B.count_zeros() == $T::BITS - 2);
-            assert!(C.count_zeros() == $T::BITS - 5);
-        }
+            fn test_count_zeros() {
+                assert!(A.count_zeros() == $T::BITS - 3);
+                assert!(B.count_zeros() == $T::BITS - 2);
+                assert!(C.count_zeros() == $T::BITS - 5);
+            }
 
-        #[test]
-        fn test_leading_trailing_ones() {
-            let a: $T = 0b0101_1111;
-            assert_eq!(a.trailing_ones(), 5);
-            assert_eq!((!a).leading_ones(), $T::BITS - 7);
+            fn test_leading_trailing_ones() {
+                const A: $T = 0b0101_1111;
+                assert_eq_const_safe!(A.trailing_ones(), 5);
+                assert_eq_const_safe!((!A).leading_ones(), $T::BITS - 7);
 
-            assert_eq!(a.reverse_bits().leading_ones(), 5);
+                assert_eq_const_safe!(A.reverse_bits().leading_ones(), 5);
 
-            assert_eq!(_1.leading_ones(), $T::BITS);
-            assert_eq!(_1.trailing_ones(), $T::BITS);
+                assert_eq_const_safe!(_1.leading_ones(), $T::BITS);
+                assert_eq_const_safe!(_1.trailing_ones(), $T::BITS);
 
-            assert_eq!((_1 << 1).trailing_ones(), 0);
-            assert_eq!((_1 >> 1).leading_ones(), 0);
+                assert_eq_const_safe!((_1 << 1).trailing_ones(), 0);
+                assert_eq_const_safe!((_1 >> 1).leading_ones(), 0);
 
-            assert_eq!((_1 << 1).leading_ones(), $T::BITS - 1);
-            assert_eq!((_1 >> 1).trailing_ones(), $T::BITS - 1);
+                assert_eq_const_safe!((_1 << 1).leading_ones(), $T::BITS - 1);
+                assert_eq_const_safe!((_1 >> 1).trailing_ones(), $T::BITS - 1);
 
-            assert_eq!(_0.leading_ones(), 0);
-            assert_eq!(_0.trailing_ones(), 0);
+                assert_eq_const_safe!(_0.leading_ones(), 0);
+                assert_eq_const_safe!(_0.trailing_ones(), 0);
 
-            let x: $T = 0b0010_1100;
-            assert_eq!(x.leading_ones(), 0);
-            assert_eq!(x.trailing_ones(), 0);
-        }
+                const X: $T = 0b0010_1100;
+                assert_eq_const_safe!(X.leading_ones(), 0);
+                assert_eq_const_safe!(X.trailing_ones(), 0);
+            }
 
-        #[test]
-        fn test_rotate() {
-            assert_eq!(A.rotate_left(6).rotate_right(2).rotate_right(4), A);
-            assert_eq!(B.rotate_left(3).rotate_left(2).rotate_right(5), B);
-            assert_eq!(C.rotate_left(6).rotate_right(2).rotate_right(4), C);
-
-            // Rotating these should make no difference
-            //
-            // We test using 124 bits because to ensure that overlong bit shifts do
-            // not cause undefined behaviour. See #10183.
-            assert_eq!(_0.rotate_left(124), _0);
-            assert_eq!(_1.rotate_left(124), _1);
-            assert_eq!(_0.rotate_right(124), _0);
-            assert_eq!(_1.rotate_right(124), _1);
-
-            // Rotating by 0 should have no effect
-            assert_eq!(A.rotate_left(0), A);
-            assert_eq!(B.rotate_left(0), B);
-            assert_eq!(C.rotate_left(0), C);
-            // Rotating by a multiple of word size should also have no effect
-            assert_eq!(A.rotate_left(128), A);
-            assert_eq!(B.rotate_left(128), B);
-            assert_eq!(C.rotate_left(128), C);
-        }
+            fn test_rotate() {
+                assert_eq_const_safe!(A.rotate_left(6).rotate_right(2).rotate_right(4), A);
+                assert_eq_const_safe!(B.rotate_left(3).rotate_left(2).rotate_right(5), B);
+                assert_eq_const_safe!(C.rotate_left(6).rotate_right(2).rotate_right(4), C);
+
+                // Rotating these should make no difference
+                //
+                // We test using 124 bits because to ensure that overlong bit shifts do
+                // not cause undefined behaviour. See #10183.
+                assert_eq_const_safe!(_0.rotate_left(124), _0);
+                assert_eq_const_safe!(_1.rotate_left(124), _1);
+                assert_eq_const_safe!(_0.rotate_right(124), _0);
+                assert_eq_const_safe!(_1.rotate_right(124), _1);
+
+                // Rotating by 0 should have no effect
+                assert_eq_const_safe!(A.rotate_left(0), A);
+                assert_eq_const_safe!(B.rotate_left(0), B);
+                assert_eq_const_safe!(C.rotate_left(0), C);
+                // Rotating by a multiple of word size should also have no effect
+                assert_eq_const_safe!(A.rotate_left(128), A);
+                assert_eq_const_safe!(B.rotate_left(128), B);
+                assert_eq_const_safe!(C.rotate_left(128), C);
+            }
 
-        #[test]
-        fn test_swap_bytes() {
-            assert_eq!(A.swap_bytes().swap_bytes(), A);
-            assert_eq!(B.swap_bytes().swap_bytes(), B);
-            assert_eq!(C.swap_bytes().swap_bytes(), C);
-
-            // Swapping these should make no difference
-            assert_eq!(_0.swap_bytes(), _0);
-            assert_eq!(_1.swap_bytes(), _1);
-        }
+            fn test_swap_bytes() {
+                assert_eq_const_safe!(A.swap_bytes().swap_bytes(), A);
+                assert_eq_const_safe!(B.swap_bytes().swap_bytes(), B);
+                assert_eq_const_safe!(C.swap_bytes().swap_bytes(), C);
 
-        #[test]
-        fn test_reverse_bits() {
-            assert_eq!(A.reverse_bits().reverse_bits(), A);
-            assert_eq!(B.reverse_bits().reverse_bits(), B);
-            assert_eq!(C.reverse_bits().reverse_bits(), C);
-
-            // Swapping these should make no difference
-            assert_eq!(_0.reverse_bits(), _0);
-            assert_eq!(_1.reverse_bits(), _1);
-        }
+                // Swapping these should make no difference
+                assert_eq_const_safe!(_0.swap_bytes(), _0);
+                assert_eq_const_safe!(_1.swap_bytes(), _1);
+            }
 
-        #[test]
-        fn test_le() {
-            assert_eq!($T::from_le(A.to_le()), A);
-            assert_eq!($T::from_le(B.to_le()), B);
-            assert_eq!($T::from_le(C.to_le()), C);
-            assert_eq!($T::from_le(_0), _0);
-            assert_eq!($T::from_le(_1), _1);
-            assert_eq!(_0.to_le(), _0);
-            assert_eq!(_1.to_le(), _1);
-        }
+            fn test_reverse_bits() {
+                assert_eq_const_safe!(A.reverse_bits().reverse_bits(), A);
+                assert_eq_const_safe!(B.reverse_bits().reverse_bits(), B);
+                assert_eq_const_safe!(C.reverse_bits().reverse_bits(), C);
 
-        #[test]
-        fn test_be() {
-            assert_eq!($T::from_be(A.to_be()), A);
-            assert_eq!($T::from_be(B.to_be()), B);
-            assert_eq!($T::from_be(C.to_be()), C);
-            assert_eq!($T::from_be(_0), _0);
-            assert_eq!($T::from_be(_1), _1);
-            assert_eq!(_0.to_be(), _0);
-            assert_eq!(_1.to_be(), _1);
-        }
+                // Swapping these should make no difference
+                assert_eq_const_safe!(_0.reverse_bits(), _0);
+                assert_eq_const_safe!(_1.reverse_bits(), _1);
+            }
 
-        #[test]
-        fn test_unsigned_checked_div() {
-            assert!((10 as $T).checked_div(2) == Some(5));
-            assert!((5 as $T).checked_div(0) == None);
+            fn test_le() {
+                assert_eq_const_safe!($T::from_le(A.to_le()), A);
+                assert_eq_const_safe!($T::from_le(B.to_le()), B);
+                assert_eq_const_safe!($T::from_le(C.to_le()), C);
+                assert_eq_const_safe!($T::from_le(_0), _0);
+                assert_eq_const_safe!($T::from_le(_1), _1);
+                assert_eq_const_safe!(_0.to_le(), _0);
+                assert_eq_const_safe!(_1.to_le(), _1);
+            }
+
+            fn test_be() {
+                assert_eq_const_safe!($T::from_be(A.to_be()), A);
+                assert_eq_const_safe!($T::from_be(B.to_be()), B);
+                assert_eq_const_safe!($T::from_be(C.to_be()), C);
+                assert_eq_const_safe!($T::from_be(_0), _0);
+                assert_eq_const_safe!($T::from_be(_1), _1);
+                assert_eq_const_safe!(_0.to_be(), _0);
+                assert_eq_const_safe!(_1.to_be(), _1);
+            }
+
+            fn test_unsigned_checked_div() {
+                assert_eq_const_safe!((10 as $T).checked_div(2), Some(5));
+                assert_eq_const_safe!((5 as $T).checked_div(0), None);
+            }
         }
 
-        fn from_str<T: FromStr>(t: &str) -> Option<T> {
-            FromStr::from_str(t).ok()
+        fn from_str<T: core::str::FromStr>(t: &str) -> Option<T> {
+            core::str::FromStr::from_str(t).ok()
         }
 
         #[test]
@@ -166,52 +158,55 @@ macro_rules! uint_module {
             assert_eq!(from_str::<$T>("x"), None);
         }
 
-        #[test]
-        pub fn test_parse_bytes() {
-            assert_eq!($T::from_str_radix("123", 10), Ok(123 as $T));
-            assert_eq!($T::from_str_radix("1001", 2), Ok(9 as $T));
-            assert_eq!($T::from_str_radix("123", 8), Ok(83 as $T));
-            assert_eq!(u16::from_str_radix("123", 16), Ok(291 as u16));
-            assert_eq!(u16::from_str_radix("ffff", 16), Ok(65535 as u16));
-            assert_eq!($T::from_str_radix("z", 36), Ok(35 as $T));
-
-            assert_eq!($T::from_str_radix("Z", 10).ok(), None::<$T>);
-            assert_eq!($T::from_str_radix("_", 2).ok(), None::<$T>);
-        }
+        test_runtime_and_compiletime! {
+            fn test_parse_bytes() {
+                assert_eq_const_safe!($T::from_str_radix("123", 10), Ok(123 as $T));
+                assert_eq_const_safe!($T::from_str_radix("1001", 2), Ok(9 as $T));
+                assert_eq_const_safe!($T::from_str_radix("123", 8), Ok(83 as $T));
+                assert_eq_const_safe!(u16::from_str_radix("123", 16), Ok(291 as u16));
+                assert_eq_const_safe!(u16::from_str_radix("ffff", 16), Ok(65535 as u16));
+                assert_eq_const_safe!($T::from_str_radix("z", 36), Ok(35 as $T));
+
+                assert!($T::from_str_radix("Z", 10).is_err());
+                assert!($T::from_str_radix("_", 2).is_err());
+            }
 
-        #[test]
-        fn test_pow() {
-            let mut r = 2 as $T;
-            assert_eq!(r.pow(2), 4 as $T);
-            assert_eq!(r.pow(0), 1 as $T);
-            assert_eq!(r.wrapping_pow(2), 4 as $T);
-            assert_eq!(r.wrapping_pow(0), 1 as $T);
-            assert_eq!(r.checked_pow(2), Some(4 as $T));
-            assert_eq!(r.checked_pow(0), Some(1 as $T));
-            assert_eq!(r.overflowing_pow(2), (4 as $T, false));
-            assert_eq!(r.overflowing_pow(0), (1 as $T, false));
-            assert_eq!(r.saturating_pow(2), 4 as $T);
-            assert_eq!(r.saturating_pow(0), 1 as $T);
-
-            r = MAX;
-            // use `^` to represent .pow() with no overflow.
-            // if itest::MAX == 2^j-1, then itest is a `j` bit int,
-            // so that `itest::MAX*itest::MAX == 2^(2*j)-2^(j+1)+1`,
-            // thussaturating_pow the overflowing result is exactly 1.
-            assert_eq!(r.wrapping_pow(2), 1 as $T);
-            assert_eq!(r.checked_pow(2), None);
-            assert_eq!(r.overflowing_pow(2), (1 as $T, true));
-            assert_eq!(r.saturating_pow(2), MAX);
-        }
+            fn test_pow() {
+                {
+                    const R: $T = 2;
+                    assert_eq_const_safe!(R.pow(2), 4 as $T);
+                    assert_eq_const_safe!(R.pow(0), 1 as $T);
+                    assert_eq_const_safe!(R.wrapping_pow(2), 4 as $T);
+                    assert_eq_const_safe!(R.wrapping_pow(0), 1 as $T);
+                    assert_eq_const_safe!(R.checked_pow(2), Some(4 as $T));
+                    assert_eq_const_safe!(R.checked_pow(0), Some(1 as $T));
+                    assert_eq_const_safe!(R.overflowing_pow(2), (4 as $T, false));
+                    assert_eq_const_safe!(R.overflowing_pow(0), (1 as $T, false));
+                    assert_eq_const_safe!(R.saturating_pow(2), 4 as $T);
+                    assert_eq_const_safe!(R.saturating_pow(0), 1 as $T);
+                }
+
+                {
+                    const R: $T = $T::MAX;
+                    // use `^` to represent .pow() with no overflow.
+                    // if itest::MAX == 2^j-1, then itest is a `j` bit int,
+                    // so that `itest::MAX*itest::MAX == 2^(2*j)-2^(j+1)+1`,
+                    // thussaturating_pow the overflowing result is exactly 1.
+                    assert_eq_const_safe!(R.wrapping_pow(2), 1 as $T);
+                    assert_eq_const_safe!(R.checked_pow(2), None);
+                    assert_eq_const_safe!(R.overflowing_pow(2), (1 as $T, true));
+                    assert_eq_const_safe!(R.saturating_pow(2), MAX);
+                }
+            }
 
-        #[test]
-        fn test_isqrt() {
-            assert_eq!((0 as $T).isqrt(), 0 as $T);
-            assert_eq!((1 as $T).isqrt(), 1 as $T);
-            assert_eq!((2 as $T).isqrt(), 1 as $T);
-            assert_eq!((99 as $T).isqrt(), 9 as $T);
-            assert_eq!((100 as $T).isqrt(), 10 as $T);
-            assert_eq!($T::MAX.isqrt(), (1 << ($T::BITS / 2)) - 1);
+            fn test_isqrt() {
+                assert_eq_const_safe!((0 as $T).isqrt(), 0 as $T);
+                assert_eq_const_safe!((1 as $T).isqrt(), 1 as $T);
+                assert_eq_const_safe!((2 as $T).isqrt(), 1 as $T);
+                assert_eq_const_safe!((99 as $T).isqrt(), 9 as $T);
+                assert_eq_const_safe!((100 as $T).isqrt(), 10 as $T);
+                assert_eq_const_safe!($T::MAX.isqrt(), (1 << ($T::BITS / 2)) - 1);
+            }
         }
 
         #[cfg(not(miri))] // Miri is too slow
@@ -233,85 +228,79 @@ macro_rules! uint_module {
             }
         }
 
-        #[test]
-        fn test_div_floor() {
-            assert_eq!((8 as $T).div_floor(3), 2);
-        }
+        test_runtime_and_compiletime! {
+            fn test_div_floor() {
+                assert_eq_const_safe!((8 as $T).div_floor(3), 2);
+            }
 
-        #[test]
-        fn test_div_ceil() {
-            assert_eq!((8 as $T).div_ceil(3), 3);
-        }
+            fn test_div_ceil() {
+                assert_eq_const_safe!((8 as $T).div_ceil(3), 3);
+            }
 
-        #[test]
-        fn test_next_multiple_of() {
-            assert_eq!((16 as $T).next_multiple_of(8), 16);
-            assert_eq!((23 as $T).next_multiple_of(8), 24);
-            assert_eq!(MAX.next_multiple_of(1), MAX);
-        }
+            fn test_next_multiple_of() {
+                assert_eq_const_safe!((16 as $T).next_multiple_of(8), 16);
+                assert_eq_const_safe!((23 as $T).next_multiple_of(8), 24);
+                assert_eq_const_safe!(MAX.next_multiple_of(1), MAX);
+            }
 
-        #[test]
-        fn test_checked_next_multiple_of() {
-            assert_eq!((16 as $T).checked_next_multiple_of(8), Some(16));
-            assert_eq!((23 as $T).checked_next_multiple_of(8), Some(24));
-            assert_eq!((1 as $T).checked_next_multiple_of(0), None);
-            assert_eq!(MAX.checked_next_multiple_of(2), None);
-        }
+            fn test_checked_next_multiple_of() {
+                assert_eq_const_safe!((16 as $T).checked_next_multiple_of(8), Some(16));
+                assert_eq_const_safe!((23 as $T).checked_next_multiple_of(8), Some(24));
+                assert_eq_const_safe!((1 as $T).checked_next_multiple_of(0), None);
+                assert_eq_const_safe!(MAX.checked_next_multiple_of(2), None);
+            }
 
-        #[test]
-        fn test_is_next_multiple_of() {
-            assert!((12 as $T).is_multiple_of(4));
-            assert!(!(12 as $T).is_multiple_of(5));
-            assert!((0 as $T).is_multiple_of(0));
-            assert!(!(12 as $T).is_multiple_of(0));
-        }
+            fn test_is_next_multiple_of() {
+                assert!((12 as $T).is_multiple_of(4));
+                assert!(!(12 as $T).is_multiple_of(5));
+                assert!((0 as $T).is_multiple_of(0));
+                assert!(!(12 as $T).is_multiple_of(0));
+            }
 
-        #[test]
-        fn test_carrying_add() {
-            assert_eq!($T::MAX.carrying_add(1, false), (0, true));
-            assert_eq!($T::MAX.carrying_add(0, true), (0, true));
-            assert_eq!($T::MAX.carrying_add(1, true), (1, true));
-
-            assert_eq!($T::MIN.carrying_add($T::MAX, false), ($T::MAX, false));
-            assert_eq!($T::MIN.carrying_add(0, true), (1, false));
-            assert_eq!($T::MIN.carrying_add($T::MAX, true), (0, true));
-        }
+            fn test_carrying_add() {
+                assert_eq_const_safe!($T::MAX.carrying_add(1, false), (0, true));
+                assert_eq_const_safe!($T::MAX.carrying_add(0, true), (0, true));
+                assert_eq_const_safe!($T::MAX.carrying_add(1, true), (1, true));
 
-        #[test]
-        fn test_borrowing_sub() {
-            assert_eq!($T::MIN.borrowing_sub(1, false), ($T::MAX, true));
-            assert_eq!($T::MIN.borrowing_sub(0, true), ($T::MAX, true));
-            assert_eq!($T::MIN.borrowing_sub(1, true), ($T::MAX - 1, true));
-
-            assert_eq!($T::MAX.borrowing_sub($T::MAX, false), (0, false));
-            assert_eq!($T::MAX.borrowing_sub(0, true), ($T::MAX - 1, false));
-            assert_eq!($T::MAX.borrowing_sub($T::MAX, true), ($T::MAX, true));
-        }
+                assert_eq_const_safe!($T::MIN.carrying_add($T::MAX, false), ($T::MAX, false));
+                assert_eq_const_safe!($T::MIN.carrying_add(0, true), (1, false));
+                assert_eq_const_safe!($T::MIN.carrying_add($T::MAX, true), (0, true));
+            }
 
-        #[test]
-        fn test_midpoint() {
-            assert_eq!(<$T>::midpoint(1, 3), 2);
-            assert_eq!(<$T>::midpoint(3, 1), 2);
-
-            assert_eq!(<$T>::midpoint(0, 0), 0);
-            assert_eq!(<$T>::midpoint(0, 2), 1);
-            assert_eq!(<$T>::midpoint(2, 0), 1);
-            assert_eq!(<$T>::midpoint(2, 2), 2);
-
-            assert_eq!(<$T>::midpoint(1, 4), 2);
-            assert_eq!(<$T>::midpoint(4, 1), 2);
-            assert_eq!(<$T>::midpoint(3, 4), 3);
-            assert_eq!(<$T>::midpoint(4, 3), 3);
-
-            assert_eq!(<$T>::midpoint(<$T>::MIN, <$T>::MAX), (<$T>::MAX - <$T>::MIN) / 2);
-            assert_eq!(<$T>::midpoint(<$T>::MAX, <$T>::MIN), (<$T>::MAX - <$T>::MIN) / 2);
-            assert_eq!(<$T>::midpoint(<$T>::MIN, <$T>::MIN), <$T>::MIN);
-            assert_eq!(<$T>::midpoint(<$T>::MAX, <$T>::MAX), <$T>::MAX);
-
-            assert_eq!(<$T>::midpoint(<$T>::MIN, 6), <$T>::MIN / 2 + 3);
-            assert_eq!(<$T>::midpoint(6, <$T>::MIN), <$T>::MIN / 2 + 3);
-            assert_eq!(<$T>::midpoint(<$T>::MAX, 6), (<$T>::MAX - <$T>::MIN) / 2 + 3);
-            assert_eq!(<$T>::midpoint(6, <$T>::MAX), (<$T>::MAX - <$T>::MIN) / 2 + 3);
+            fn test_borrowing_sub() {
+                assert_eq_const_safe!($T::MIN.borrowing_sub(1, false), ($T::MAX, true));
+                assert_eq_const_safe!($T::MIN.borrowing_sub(0, true), ($T::MAX, true));
+                assert_eq_const_safe!($T::MIN.borrowing_sub(1, true), ($T::MAX - 1, true));
+
+                assert_eq_const_safe!($T::MAX.borrowing_sub($T::MAX, false), (0, false));
+                assert_eq_const_safe!($T::MAX.borrowing_sub(0, true), ($T::MAX - 1, false));
+                assert_eq_const_safe!($T::MAX.borrowing_sub($T::MAX, true), ($T::MAX, true));
+            }
+
+            fn test_midpoint() {
+                assert_eq_const_safe!(<$T>::midpoint(1, 3), 2);
+                assert_eq_const_safe!(<$T>::midpoint(3, 1), 2);
+
+                assert_eq_const_safe!(<$T>::midpoint(0, 0), 0);
+                assert_eq_const_safe!(<$T>::midpoint(0, 2), 1);
+                assert_eq_const_safe!(<$T>::midpoint(2, 0), 1);
+                assert_eq_const_safe!(<$T>::midpoint(2, 2), 2);
+
+                assert_eq_const_safe!(<$T>::midpoint(1, 4), 2);
+                assert_eq_const_safe!(<$T>::midpoint(4, 1), 2);
+                assert_eq_const_safe!(<$T>::midpoint(3, 4), 3);
+                assert_eq_const_safe!(<$T>::midpoint(4, 3), 3);
+
+                assert_eq_const_safe!(<$T>::midpoint(<$T>::MIN, <$T>::MAX), (<$T>::MAX - <$T>::MIN) / 2);
+                assert_eq_const_safe!(<$T>::midpoint(<$T>::MAX, <$T>::MIN), (<$T>::MAX - <$T>::MIN) / 2);
+                assert_eq_const_safe!(<$T>::midpoint(<$T>::MIN, <$T>::MIN), <$T>::MIN);
+                assert_eq_const_safe!(<$T>::midpoint(<$T>::MAX, <$T>::MAX), <$T>::MAX);
+
+                assert_eq_const_safe!(<$T>::midpoint(<$T>::MIN, 6), <$T>::MIN / 2 + 3);
+                assert_eq_const_safe!(<$T>::midpoint(6, <$T>::MIN), <$T>::MIN / 2 + 3);
+                assert_eq_const_safe!(<$T>::midpoint(<$T>::MAX, 6), (<$T>::MAX - <$T>::MIN) / 2 + 3);
+                assert_eq_const_safe!(<$T>::midpoint(6, <$T>::MAX), (<$T>::MAX - <$T>::MIN) / 2 + 3);
+            }
         }
     };
 }

From d567fcc3018e8a9b09cbbd1a56c2f8bbf7e56438 Mon Sep 17 00:00:00 2001
From: Ralf Jung <post@ralfj.de>
Date: Mon, 21 Oct 2024 16:06:58 +0100
Subject: [PATCH 2/8] abi/compatibility: also test Option-like types

---
 tests/ui/abi/compatibility.rs | 18 +++++++++++++++++-
 1 file changed, 17 insertions(+), 1 deletion(-)

diff --git a/tests/ui/abi/compatibility.rs b/tests/ui/abi/compatibility.rs
index 28c8063a92311..33d67360ff11d 100644
--- a/tests/ui/abi/compatibility.rs
+++ b/tests/ui/abi/compatibility.rs
@@ -211,6 +211,15 @@ impl Clone for Zst {
     }
 }
 
+enum Either<T, U> {
+    Left(T),
+    Right(U),
+}
+enum Either2<T, U> {
+    Left(T),
+    Right(U, ()),
+}
+
 #[repr(C)]
 enum ReprCEnum<T> {
     Variant1,
@@ -328,7 +337,8 @@ mod unsized_ {
     test_transparent_unsized!(dyn_trait, dyn Any);
 }
 
-// RFC 3391 <https://rust-lang.github.io/rfcs/3391-result_ffi_guarantees.html>.
+// RFC 3391 <https://rust-lang.github.io/rfcs/3391-result_ffi_guarantees.html>, including the
+// extension ratified at <https://github.com/rust-lang/rust/pull/130628#issuecomment-2402761599>.
 macro_rules! test_nonnull {
     ($name:ident, $t:ty) => {
         mod $name {
@@ -340,6 +350,12 @@ macro_rules! test_nonnull {
             test_abi_compatible!(result_ok_zst, Result<Zst, $t>, $t);
             test_abi_compatible!(result_err_arr, Result<$t, [i8; 0]>, $t);
             test_abi_compatible!(result_ok_arr, Result<[i8; 0], $t>, $t);
+            test_abi_compatible!(result_err_void, Result<$t, Void>, $t);
+            test_abi_compatible!(result_ok_void, Result<Void, $t>, $t);
+            test_abi_compatible!(either_err_zst, Either<$t, Zst>, $t);
+            test_abi_compatible!(either_ok_zst, Either<Zst, $t>, $t);
+            test_abi_compatible!(either2_err_zst, Either2<$t, Zst>, $t);
+            test_abi_compatible!(either2_err_arr, Either2<$t, [i8; 0]>, $t);
         }
     }
 }

From 25365aeacf32715f2a4cd0d63326139d16e3c7ed Mon Sep 17 00:00:00 2001
From: lcnr <rust@lcnr.de>
Date: Tue, 22 Oct 2024 08:20:23 +0200
Subject: [PATCH 3/8] fix typo

---
 .../rustc_next_trait_solver/src/solve/eval_ctxt/canonical.rs    | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/compiler/rustc_next_trait_solver/src/solve/eval_ctxt/canonical.rs b/compiler/rustc_next_trait_solver/src/solve/eval_ctxt/canonical.rs
index 71ce0cce77224..e2fd0dd2a25fa 100644
--- a/compiler/rustc_next_trait_solver/src/solve/eval_ctxt/canonical.rs
+++ b/compiler/rustc_next_trait_solver/src/solve/eval_ctxt/canonical.rs
@@ -170,7 +170,7 @@ where
         //
         // We don't do so for `NormalizesTo` goals as we erased the expected term and
         // bailing with overflow here would prevent us from detecting a type-mismatch,
-        // causing a coherence error in diesel, see #131969. We still bail with verflow
+        // causing a coherence error in diesel, see #131969. We still bail with overflow
         // when later returning from the parent AliasRelate goal.
         if !self.is_normalizes_to_goal {
             let num_non_region_vars =

From d6ce2bd1de944c9c7fbb2a7095a12304e4484935 Mon Sep 17 00:00:00 2001
From: lcnr <rust@lcnr.de>
Date: Tue, 22 Oct 2024 08:27:11 +0200
Subject: [PATCH 4/8] remove unused field

---
 .../src/solve/eval_ctxt/mod.rs                  |  2 +-
 .../src/solve/inspect/build.rs                  | 16 ++++++----------
 .../src/solve/inspect/analyse.rs                |  2 +-
 compiler/rustc_type_ir/src/solve/inspect.rs     | 17 +++++------------
 4 files changed, 13 insertions(+), 24 deletions(-)

diff --git a/compiler/rustc_next_trait_solver/src/solve/eval_ctxt/mod.rs b/compiler/rustc_next_trait_solver/src/solve/eval_ctxt/mod.rs
index cbefc826fb7d8..250174e033e3a 100644
--- a/compiler/rustc_next_trait_solver/src/solve/eval_ctxt/mod.rs
+++ b/compiler/rustc_next_trait_solver/src/solve/eval_ctxt/mod.rs
@@ -291,7 +291,7 @@ where
             search_graph,
             nested_goals: NestedGoals::new(),
             tainted: Ok(()),
-            inspect: canonical_goal_evaluation.new_goal_evaluation_step(var_values, input),
+            inspect: canonical_goal_evaluation.new_goal_evaluation_step(var_values),
         };
 
         for &(key, ty) in &input.predefined_opaques_in_body.opaque_types {
diff --git a/compiler/rustc_next_trait_solver/src/solve/inspect/build.rs b/compiler/rustc_next_trait_solver/src/solve/inspect/build.rs
index 85474bf37b448..1607fbb1b6a7b 100644
--- a/compiler/rustc_next_trait_solver/src/solve/inspect/build.rs
+++ b/compiler/rustc_next_trait_solver/src/solve/inspect/build.rs
@@ -13,7 +13,7 @@ use rustc_type_ir::{self as ty, Interner};
 use crate::delegate::SolverDelegate;
 use crate::solve::eval_ctxt::canonical;
 use crate::solve::{
-    CanonicalInput, Certainty, GenerateProofTree, Goal, GoalEvaluationKind, GoalSource, QueryInput,
+    CanonicalInput, Certainty, GenerateProofTree, Goal, GoalEvaluationKind, GoalSource,
     QueryResult, inspect,
 };
 
@@ -119,6 +119,9 @@ impl<I: Interner> WipCanonicalGoalEvaluation<I> {
     }
 }
 
+/// This only exists during proof tree building and does not have
+/// a corresponding struct in `inspect`. We need this to track a
+/// bunch of metadata about the current evaluation.
 #[derive_where(PartialEq, Eq, Debug; I: Interner)]
 struct WipCanonicalGoalEvaluationStep<I: Interner> {
     /// Unlike `EvalCtxt::var_values`, we append a new
@@ -128,7 +131,6 @@ struct WipCanonicalGoalEvaluationStep<I: Interner> {
     /// This is necessary as we otherwise don't unify these
     /// vars when instantiating multiple `CanonicalState`.
     var_values: Vec<I::GenericArg>,
-    instantiated_goal: QueryInput<I, I::Predicate>,
     probe_depth: usize,
     evaluation: WipProbe<I>,
 }
@@ -145,16 +147,12 @@ impl<I: Interner> WipCanonicalGoalEvaluationStep<I> {
         current
     }
 
-    fn finalize(self) -> inspect::CanonicalGoalEvaluationStep<I> {
+    fn finalize(self) -> inspect::Probe<I> {
         let evaluation = self.evaluation.finalize();
         match evaluation.kind {
-            inspect::ProbeKind::Root { .. } => (),
+            inspect::ProbeKind::Root { .. } => evaluation,
             _ => unreachable!("unexpected root evaluation: {evaluation:?}"),
         }
-        inspect::CanonicalGoalEvaluationStep {
-            instantiated_goal: self.instantiated_goal,
-            evaluation,
-        }
     }
 }
 
@@ -328,11 +326,9 @@ impl<D: SolverDelegate<Interner = I>, I: Interner> ProofTreeBuilder<D> {
     pub(crate) fn new_goal_evaluation_step(
         &mut self,
         var_values: ty::CanonicalVarValues<I>,
-        instantiated_goal: QueryInput<I, I::Predicate>,
     ) -> ProofTreeBuilder<D> {
         self.nested(|| WipCanonicalGoalEvaluationStep {
             var_values: var_values.var_values.to_vec(),
-            instantiated_goal,
             evaluation: WipProbe {
                 initial_num_var_values: var_values.len(),
                 steps: vec![],
diff --git a/compiler/rustc_trait_selection/src/solve/inspect/analyse.rs b/compiler/rustc_trait_selection/src/solve/inspect/analyse.rs
index 4975a9ce0c757..e735020a63e66 100644
--- a/compiler/rustc_trait_selection/src/solve/inspect/analyse.rs
+++ b/compiler/rustc_trait_selection/src/solve/inspect/analyse.rs
@@ -344,7 +344,7 @@ impl<'a, 'tcx> InspectGoal<'a, 'tcx> {
         };
 
         let mut nested_goals = vec![];
-        self.candidates_recur(&mut candidates, &mut nested_goals, &last_eval_step.evaluation);
+        self.candidates_recur(&mut candidates, &mut nested_goals, &last_eval_step);
 
         candidates
     }
diff --git a/compiler/rustc_type_ir/src/solve/inspect.rs b/compiler/rustc_type_ir/src/solve/inspect.rs
index 138ba8bac8871..d0e618dc6f96d 100644
--- a/compiler/rustc_type_ir/src/solve/inspect.rs
+++ b/compiler/rustc_type_ir/src/solve/inspect.rs
@@ -23,9 +23,7 @@ use std::hash::Hash;
 use derive_where::derive_where;
 use rustc_type_ir_macros::{TypeFoldable_Generic, TypeVisitable_Generic};
 
-use crate::solve::{
-    CandidateSource, CanonicalInput, Certainty, Goal, GoalSource, QueryInput, QueryResult,
-};
+use crate::solve::{CandidateSource, CanonicalInput, Certainty, Goal, GoalSource, QueryResult};
 use crate::{Canonical, CanonicalVarValues, Interner};
 
 /// Some `data` together with information about how they relate to the input
@@ -69,15 +67,10 @@ pub struct CanonicalGoalEvaluation<I: Interner> {
 #[derive_where(PartialEq, Eq, Hash, Debug; I: Interner)]
 pub enum CanonicalGoalEvaluationKind<I: Interner> {
     Overflow,
-    Evaluation { final_revision: CanonicalGoalEvaluationStep<I> },
-}
-
-#[derive_where(PartialEq, Eq, Hash, Debug; I: Interner)]
-pub struct CanonicalGoalEvaluationStep<I: Interner> {
-    pub instantiated_goal: QueryInput<I, I::Predicate>,
-
-    /// The actual evaluation of the goal, always `ProbeKind::Root`.
-    pub evaluation: Probe<I>,
+    Evaluation {
+        /// This is always `ProbeKind::Root`.
+        final_revision: Probe<I>,
+    },
 }
 
 /// A self-contained computation during trait solving. This either

From 5b12d906bb66d308fb3e94d6d79e076fa87c7f7c Mon Sep 17 00:00:00 2001
From: Slanterns <slanterns.w@gmail.com>
Date: Tue, 22 Oct 2024 01:08:15 -0700
Subject: [PATCH 5/8] optimize `Rc<T>::default`

---
 library/alloc/src/rc.rs | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/library/alloc/src/rc.rs b/library/alloc/src/rc.rs
index e98ae7c31ad06..582d850e14b6d 100644
--- a/library/alloc/src/rc.rs
+++ b/library/alloc/src/rc.rs
@@ -2312,7 +2312,16 @@ impl<T: Default> Default for Rc<T> {
     /// ```
     #[inline]
     fn default() -> Rc<T> {
-        Rc::new(Default::default())
+        unsafe {
+            Self::from_inner(
+                Box::leak(Box::write(Box::new_uninit(), RcInner {
+                    strong: Cell::new(1),
+                    weak: Cell::new(1),
+                    value: T::default(),
+                }))
+                .into(),
+            )
+        }
     }
 }
 

From 7782401c520ab1e744dbcf58d0f0254672da9026 Mon Sep 17 00:00:00 2001
From: Slanterns <slanterns.w@gmail.com>
Date: Tue, 22 Oct 2024 01:33:22 -0700
Subject: [PATCH 6/8] add codegen test

---
 tests/codegen/placement-new.rs | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/tests/codegen/placement-new.rs b/tests/codegen/placement-new.rs
index edb25df5eb4dc..0ec2b6a6f20e7 100644
--- a/tests/codegen/placement-new.rs
+++ b/tests/codegen/placement-new.rs
@@ -1,9 +1,11 @@
 //@ compile-flags: -O
+//@ compile-flags: -Zmerge-functions=disabled
 #![crate_type = "lib"]
 
 // Test to check that types with "complex" destructors, but trivial `Default` impls
 // are constructed directly into the allocation in `Box::default` and `Arc::default`.
 
+use std::rc::Rc;
 use std::sync::Arc;
 
 // CHECK-LABEL: @box_default_inplace
@@ -16,6 +18,16 @@ pub fn box_default_inplace() -> Box<(String, String)> {
     Box::default()
 }
 
+// CHECK-LABEL: @rc_default_inplace
+#[no_mangle]
+pub fn rc_default_inplace() -> Rc<(String, String)> {
+    // CHECK-NOT: alloca
+    // CHECK: [[RC:%.*]] = {{.*}}call {{.*}}__rust_alloc(
+    // CHECK-NOT: call void @llvm.memcpy
+    // CHECK: ret ptr [[RC]]
+    Rc::default()
+}
+
 // CHECK-LABEL: @arc_default_inplace
 #[no_mangle]
 pub fn arc_default_inplace() -> Arc<(String, String)> {

From 0a963ab2da139b177ef1e7f09efed7e4e1e8e930 Mon Sep 17 00:00:00 2001
From: Slanterns <slanterns.w@gmail.com>
Date: Tue, 22 Oct 2024 01:37:13 -0700
Subject: [PATCH 7/8] refactor `Arc<T>::default`

---
 library/alloc/src/sync.rs | 17 ++++++++++-------
 1 file changed, 10 insertions(+), 7 deletions(-)

diff --git a/library/alloc/src/sync.rs b/library/alloc/src/sync.rs
index acbc325a51415..13677245e98c2 100644
--- a/library/alloc/src/sync.rs
+++ b/library/alloc/src/sync.rs
@@ -3447,13 +3447,16 @@ impl<T: Default> Default for Arc<T> {
     /// assert_eq!(*x, 0);
     /// ```
     fn default() -> Arc<T> {
-        let x = Box::into_raw(Box::write(Box::new_uninit(), ArcInner {
-            strong: atomic::AtomicUsize::new(1),
-            weak: atomic::AtomicUsize::new(1),
-            data: T::default(),
-        }));
-        // SAFETY: `Box::into_raw` consumes the `Box` and never returns null
-        unsafe { Self::from_inner(NonNull::new_unchecked(x)) }
+        unsafe {
+            Self::from_inner(
+                Box::leak(Box::write(Box::new_uninit(), ArcInner {
+                    strong: atomic::AtomicUsize::new(1),
+                    weak: atomic::AtomicUsize::new(1),
+                    data: T::default(),
+                }))
+                .into(),
+            )
+        }
     }
 }
 

From 1909668a88fdea755f82d143fca00e6ab5394cbe Mon Sep 17 00:00:00 2001
From: Josh Stone <jistone@redhat.com>
Date: Tue, 22 Oct 2024 10:47:42 -0700
Subject: [PATCH 8/8] relnotes: fix stabilizations of `assume_init`

Ref: https://github.com/rust-lang/blog.rust-lang.org/pull/1416
---
 RELEASES.md | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/RELEASES.md b/RELEASES.md
index ac72a1d885cbc..40ddba6dbc52e 100644
--- a/RELEASES.md
+++ b/RELEASES.md
@@ -68,15 +68,15 @@ Stabilized APIs
 - [`impl Default for std::collections::vec_deque::Iter`](https://doc.rust-lang.org/nightly/std/collections/vec_deque/struct.Iter.html#impl-Default-for-Iter%3C'_,+T%3E)
 - [`impl Default for std::collections::vec_deque::IterMut`](https://doc.rust-lang.org/nightly/std/collections/vec_deque/struct.IterMut.html#impl-Default-for-IterMut%3C'_,+T%3E)
 - [`Rc<T>::new_uninit`](https://doc.rust-lang.org/nightly/std/rc/struct.Rc.html#method.new_uninit)
-- [`Rc<T>::assume_init`](https://doc.rust-lang.org/nightly/std/rc/struct.Rc.html#method.assume_init)
+- [`Rc<MaybeUninit<T>>::assume_init`](https://doc.rust-lang.org/nightly/std/rc/struct.Rc.html#method.assume_init)
 - [`Rc<[T]>::new_uninit_slice`](https://doc.rust-lang.org/nightly/std/rc/struct.Rc.html#method.new_uninit_slice)
 - [`Rc<[MaybeUninit<T>]>::assume_init`](https://doc.rust-lang.org/nightly/std/rc/struct.Rc.html#method.assume_init-1)
 - [`Arc<T>::new_uninit`](https://doc.rust-lang.org/nightly/std/sync/struct.Arc.html#method.new_uninit)
-- [`Arc<T>::assume_init`](https://doc.rust-lang.org/nightly/std/sync/struct.Arc.html#method.assume_init)
+- [`Arc<MaybeUninit<T>>::assume_init`](https://doc.rust-lang.org/nightly/std/sync/struct.Arc.html#method.assume_init)
 - [`Arc<[T]>::new_uninit_slice`](https://doc.rust-lang.org/nightly/std/sync/struct.Arc.html#method.new_uninit_slice)
 - [`Arc<[MaybeUninit<T>]>::assume_init`](https://doc.rust-lang.org/nightly/std/sync/struct.Arc.html#method.assume_init-1)
 - [`Box<T>::new_uninit`](https://doc.rust-lang.org/nightly/std/boxed/struct.Box.html#method.new_uninit)
-- [`Box<T>::assume_init`](https://doc.rust-lang.org/nightly/std/boxed/struct.Box.html#method.assume_init)
+- [`Box<MaybeUninit<T>>::assume_init`](https://doc.rust-lang.org/nightly/std/boxed/struct.Box.html#method.assume_init)
 - [`Box<[T]>::new_uninit_slice`](https://doc.rust-lang.org/nightly/std/boxed/struct.Box.html#method.new_uninit_slice)
 - [`Box<[MaybeUninit<T>]>::assume_init`](https://doc.rust-lang.org/nightly/std/boxed/struct.Box.html#method.assume_init-1)
 - [`core::arch::x86_64::_bextri_u64`](https://doc.rust-lang.org/stable/core/arch/x86_64/fn._bextri_u64.html)