Updated RELEASES.md for 1.23.0

Author: Aaron Power

RELEASES.md

@@ -1,3 +1,105 @@
+Version 1.23.0 (2018-01-04)
+==========================
+
+Language
+--------
+- [Fixed displaying duplicate errors on some trait bounds.][45772]
+
+Compiler
+--------
+- [Enabled `TrapUnreachable` in LLVM which should prevent some cases of
+  undefined behaviour.][45920]
+- [rustc now suggests renaming import if names clash.][45660]
+- [Display errors/warnings correctly when there are zero-width or
+  wide characters.][45711]
+- [rustc now uses subtyping on the left hand side of binary operations.][45435]
+  Which should fix some confusing errors in some operations.
+- [Bumped the minimum LLVM to 3.9][45326]
+- [rustc now avoids unnecessary copies of arguments that are
+  simple bindings][45380] This should improve memory usage on average by 5-10%.
+- [Updated musl used to build musl rustc to 1.1.17][45393]
+
+Libraries
+---------
+- [impl `From<T>` for `Mutex<T>` and `RwLock<T>`][46082]
+- [Allow a trailling comma in `assert_eq/ne` macro][45887]
+- [Implement Hash for raw pointers to unsized types][45483]
+- [impl `From<*mut T>` for `AtomicPtr<T>`][45610]
+- [impl `From<{number_size}>` for `Atomic{number_size}`][45610] eg. `From<u8>`
+  for `AtomicU8`.
+- [Removed the `T: Sync` requirement for `RwLock<T>: Send`][45267]
+- [Removed `T: Sized` requirement for `<*const T>::as_ref`
+  and `<*const T>::as_mut`][44932]
+- [Optimized `Thread::{park, unpark}` implementation][45524]
+- [Improved `SliceExt::binary_search` performance.][45333]
+- [Optimized `Read::read_to_end`.][46050] This increase file read speed and for
+  small files reduce the number of syscalls.
+
+Stabilized APIs
+---------------
+
+Cargo
+-----
+- [Cargo now supports alternative registries][cargo/4506]
+- [Cargo now supports uninstallation of multiple packages][cargo/4561]
+  eg. `cargo uninstall foo bar` uninstalls `foo` and `bar`.
+- [Added unit test checking to `cargo check`][cargo/4592]
+- [Cargo now lets you install a specific version
+  using `cargo install --version`][cargo/4637]
+
+Misc
+----
+- [Releases now ship with the Cargo book documentation.][45692]
+- [rustdoc now prints rendering warnings on every run.][45324]
+- [Release tarballs now come with rustfmt][45903]
+
+Compatibility Notes
+-------------------
+- [`fmt::Arguments` can no longer be shared across threads.][45198]
+- [Changes have been made to type equality to make it more correct,
+  in rare cases this could break some code.][45853] [Tracking issue for
+  further information][45852]
+- [Changed how closures are stored, as a result of this change you can no longer
+  have a situation where a closure directly calls itself.][45879]
+- [`char::escape_debug` now uses Unicode 10 over 9.][45571]
+- [Upgraded Android SDK to 27, and NDK to r15c.][45580] This drops support for
+  Android 9, the minimum supported version is Android 14.
+- [Refactored type memory layouts and ABIs.][45225] This reduce code generated
+  for a lot of types.
+  
+[44932]: https://github.com/rust-lang/rust/pull/44932
+[45198]: https://github.com/rust-lang/rust/pull/45198
+[45225]: https://github.com/rust-lang/rust/pull/45225
+[45267]: https://github.com/rust-lang/rust/pull/45267
+[45324]: https://github.com/rust-lang/rust/pull/45324
+[45326]: https://github.com/rust-lang/rust/pull/45326
+[45333]: https://github.com/rust-lang/rust/pull/45333
+[45380]: https://github.com/rust-lang/rust/pull/45380
+[45393]: https://github.com/rust-lang/rust/pull/45393
+[45435]: https://github.com/rust-lang/rust/pull/45435
+[45483]: https://github.com/rust-lang/rust/pull/45483
+[45524]: https://github.com/rust-lang/rust/pull/45524
+[45571]: https://github.com/rust-lang/rust/pull/45571
+[45580]: https://github.com/rust-lang/rust/pull/45580
+[45610]: https://github.com/rust-lang/rust/pull/45610
+[45660]: https://github.com/rust-lang/rust/pull/45660
+[45692]: https://github.com/rust-lang/rust/pull/45692
+[45711]: https://github.com/rust-lang/rust/pull/45711
+[45772]: https://github.com/rust-lang/rust/pull/45772
+[45852]: https://github.com/rust-lang/rust/issues/45852
+[45853]: https://github.com/rust-lang/rust/pull/45853
+[45879]: https://github.com/rust-lang/rust/pull/45879
+[45887]: https://github.com/rust-lang/rust/pull/45887
+[45903]: https://github.com/rust-lang/rust/pull/45903
+[45920]: https://github.com/rust-lang/rust/pull/45920
+[46050]: https://github.com/rust-lang/rust/pull/46050
+[46082]: https://github.com/rust-lang/rust/pull/46082
+[cargo/4506]: https://github.com/rust-lang/cargo/pull/4506
+[cargo/4561]: https://github.com/rust-lang/cargo/pull/4561
+[cargo/4592]: https://github.com/rust-lang/cargo/pull/4592
+[cargo/4637]: https://github.com/rust-lang/cargo/pull/4637
+
+
 Version 1.22.1 (2017-11-22)
 ==========================