+Compatibility Notes
+-------------------
+- [Mixing Option and Result via `?` is no longer permitted in closures for inferred types.][86831]
+- [Previously unsound code is no longer permitted where different constructors in branches
+ could require different lifetimes.][85574]
+- As previously mentioned the [`std::arch` instrinsics now uses stricter const checking][83278]
+ than before and may reject some previously accepted code.
+- [`i128` multiplication on Cortex M0+ platforms currently unconditionally causes overflow
+ when compiled with `codegen-units = 1`.][86063]
+
+[85574]: https://github.com/rust-lang/rust/issues/85574
+[86831]: https://github.com/rust-lang/rust/issues/86831
+[86063]: https://github.com/rust-lang/rust/issues/86063
+[86831]: https://github.com/rust-lang/rust/issues/86831