---------
- [Guarantee call order for `sort_by_cached_key`][89621]
- [Improve `Duration::try_from_secs_f32`/`f64` accuracy by directly processing exponent and mantissa][90247]
-- [Switch all libraries to the 2021 edition][92068]
-- [Make `Instant::{duration_since, elapsed, sub}` saturating and remove workarounds][89926]
-- [Change PhantomData type for `BuildHasherDefault` (and more)][92630]
+- [Make `Instant::{duration_since, elapsed, sub}` saturating][89926]
+- [Remove non-monotonic clocks workarounds in `Instant::now`][89926]
+- [Make `BuildHasherDefault`, `iter::Empty` and `future::Pending` covariant][92630]
Stabilized APIs
---------------
Misc
----
-- [Add manifest docs fallback for tier-2 platforms.][92800]
+- [Ship docs on Tier 2 platforms by reusing the closest Tier 1 platform docs][92800]
- [Drop rustc-docs from complete profile][93742]
- [bootstrap: tidy up flag handling for llvm build][93918]
Compatibility Notes
-------------------
- [Remove compiler-rt linking hack on Android][83822]
+- [Mitigations for platforms with non-monotonic clocks have been removed from
+ `Instant::now`][89926]. On platforms that don't provide monotonic clocks, an
+ instant is not guaranteed to be greater than an earlier instant anymore.
+- [`Instant::{duration_since, elapsed, sub}` do not panic anymore on underflow,
+ saturating to `0` instead][89926]. In the real world the panic happened mostly
+ on platforms with buggy monotonic clock implementations rather than catching
+ programming errors like reversing the start and end times. Such programming
+ errors will now results in `0` rather than a panic.
+- In a future release we're planning to increase the baseline requirements for
+ the Linux kernel to version 3.2, and for glibc to version 2.17. We'd love
+ your feedback in [PR #95026][95026].
Internal Changes
----------------
improvements to the internals and overall performance of rustc
and related tools.
-<!-- TODO: anything to highlight? -->
+- [Switch all libraries to the 2021 edition][92068]
[83822]: https://github.com/rust-lang/rust/pull/83822
[86374]: https://github.com/rust-lang/rust/pull/86374
[93742]: https://github.com/rust-lang/rust/pull/93742
[93824]: https://github.com/rust-lang/rust/pull/93824
[93918]: https://github.com/rust-lang/rust/pull/93918
+[95026]: https://github.com/rust-lang/rust/pull/95026
[cargo/10086]: https://github.com/rust-lang/cargo/pull/10086
[cargo/10245]: https://github.com/rust-lang/cargo/pull/10245