rust/RELEASES.md
kennytm 7c8b36f6f1 Rollup merge of #46157 - martinlindhe:master, r=kennytm
fix some typos

This is the result of me testing out a WIP source code typo-finder
and your project was the random target this time.
2017-11-22 01:13:06 +08:00

5781 lines
302 KiB
Markdown

Version 1.22.0 (2017-11-23)
==========================
Language
--------
- [`non_snake_case` lint now allows extern no-mangle functions][44966]
- [Now accepts underscores in unicode escapes][43716]
- [`T op= &T` now works for numeric types.][44287] eg. `let mut x = 2; x += &8;`
- [types that impl `Drop` are now allowed in `const` and `static` types][44456]
Compiler
--------
- [rustc now defaults to having 16 codegen units at debug on supported platforms.][45064]
- [rustc will no longer inline in codegen units when compiling for debug][45075]
This should decrease compile times for debug builds.
- [strict memory alignment now enabled on ARMv6][45094]
- [Remove support for the PNaCl target `le32-unknown-nacl`][45041]
Libraries
---------
- [Allow atomic operations up to 32 bits
on `armv5te_unknown_linux_gnueabi`][44978]
- [`Box<Error>` now impls `From<Cow<str>>`][44466]
- [`std::mem::Discriminant` is now guaranteed to be `Send + Sync`][45095]
- [`fs::copy` now returns the length of the main stream on NTFS.][44895]
- [Properly detect overflow in `Instant += Duration`.][44220]
- [impl `Hasher` for `{&mut Hasher, Box<Hasher>}`][44015]
- [impl `fmt::Debug` for `SplitWhitespace`.][44303]
- [`Option<T>` now impls `Try`][42526] This allows for using `?` with `Option` types.
Stabilized APIs
---------------
Cargo
-----
- [Cargo will now build multi file examples in subdirectories of the `examples`
folder that have a `main.rs` file.][cargo/4496]
- [Changed `[root]` to `[package]` in `Cargo.lock`][cargo/4571] Packages with
the old format will continue to work and can be updated with `cargo update`.
- [Now supports vendoring git repositories][cargo/3992]
Misc
----
- [`libbacktrace` is now available on Apple platforms.][44251]
- [Stabilised the `compile_fail` attribute for code fences in doc-comments.][43949]
This now lets you specify that a given code example will fail to compile.
Compatibility Notes
-------------------
- [The minimum Android version that rustc can build for has been bumped
to `4.0` from `2.3`][45656]
- [Allowing `T op= &T` for numeric types has broken some type
inference cases][45480]
[42526]: https://github.com/rust-lang/rust/pull/42526
[43017]: https://github.com/rust-lang/rust/pull/43017
[43716]: https://github.com/rust-lang/rust/pull/43716
[43949]: https://github.com/rust-lang/rust/pull/43949
[44015]: https://github.com/rust-lang/rust/pull/44015
[44220]: https://github.com/rust-lang/rust/pull/44220
[44251]: https://github.com/rust-lang/rust/pull/44251
[44287]: https://github.com/rust-lang/rust/pull/44287
[44303]: https://github.com/rust-lang/rust/pull/44303
[44456]: https://github.com/rust-lang/rust/pull/44456
[44466]: https://github.com/rust-lang/rust/pull/44466
[44895]: https://github.com/rust-lang/rust/pull/44895
[44966]: https://github.com/rust-lang/rust/pull/44966
[44978]: https://github.com/rust-lang/rust/pull/44978
[45041]: https://github.com/rust-lang/rust/pull/45041
[45064]: https://github.com/rust-lang/rust/pull/45064
[45075]: https://github.com/rust-lang/rust/pull/45075
[45094]: https://github.com/rust-lang/rust/pull/45094
[45095]: https://github.com/rust-lang/rust/pull/45095
[45480]: https://github.com/rust-lang/rust/issues/45480
[45656]: https://github.com/rust-lang/rust/pull/45656
[cargo/3992]: https://github.com/rust-lang/cargo/pull/3992
[cargo/4496]: https://github.com/rust-lang/cargo/pull/4496
[cargo/4571]: https://github.com/rust-lang/cargo/pull/4571
Version 1.21.0 (2017-10-12)
==========================
Language
--------
- [You can now use static references for literals.][43838]
Example:
```rust
fn main() {
let x: &'static u32 = &0;
}
```
- [Relaxed path syntax. Optional `::` before `<` is now allowed in all contexts.][43540]
Example:
```rust
my_macro!(Vec<i32>::new); // Always worked
my_macro!(Vec::<i32>::new); // Now works
```
Compiler
--------
- [Upgraded jemalloc to 4.5.0][43911]
- [Enabled unwinding panics on Redox][43917]
- [Now runs LLVM in parallel during translation phase.][43506]
This should reduce peak memory usage.
Libraries
---------
- [Generate builtin impls for `Clone` for all arrays and tuples that
are `T: Clone`][43690]
- [`Stdin`, `Stdout`, and `Stderr` now implement `AsRawFd`.][43459]
- [`Rc` and `Arc` now implement `From<&[T]> where T: Clone`, `From<str>`,
`From<String>`, `From<Box<T>> where T: ?Sized`, and `From<Vec<T>>`.][42565]
Stabilized APIs
---------------
[`std::mem::discriminant`]
Cargo
-----
- [You can now call `cargo install` with multiple package names][cargo/4216]
- [Cargo commands inside a virtual workspace will now implicitly
pass `--all`][cargo/4335]
- [Added a `[patch]` section to `Cargo.toml` to handle
prepublication dependencies][cargo/4123] [RFC 1969]
- [`include` & `exclude` fields in `Cargo.toml` now accept gitignore
like patterns][cargo/4270]
- [Added the `--all-targets` option][cargo/4400]
- [Using required dependencies as a feature is now deprecated and emits
a warning][cargo/4364]
Misc
----
- [Cargo docs are moving][43916]
to [doc.rust-lang.org/cargo](https://doc.rust-lang.org/cargo)
- [The rustdoc book is now available][43863]
at [doc.rust-lang.org/rustdoc](https://doc.rust-lang.org/rustdoc)
- [Added a preview of RLS has been made available through rustup][44204]
Install with `rustup component add rls-preview`
- [`std::os` documentation for Unix, Linux, and Windows now appears on doc.rust-lang.org][43348]
Previously only showed `std::os::unix`.
Compatibility Notes
-------------------
- [Changes in method matching against higher-ranked types][43880] This may cause
breakage in subtyping corner cases. [A more in-depth explanation is available.][info/43880]
- [rustc's JSON error output's byte position start at top of file.][42973]
Was previously relative to the rustc's internal `CodeMap` struct which
required the unstable library `libsyntax` to correctly use.
- [`unused_results` lint no longer ignores booleans][43728]
[42565]: https://github.com/rust-lang/rust/pull/42565
[42973]: https://github.com/rust-lang/rust/pull/42973
[43348]: https://github.com/rust-lang/rust/pull/43348
[43459]: https://github.com/rust-lang/rust/pull/43459
[43506]: https://github.com/rust-lang/rust/pull/43506
[43540]: https://github.com/rust-lang/rust/pull/43540
[43690]: https://github.com/rust-lang/rust/pull/43690
[43728]: https://github.com/rust-lang/rust/pull/43728
[43838]: https://github.com/rust-lang/rust/pull/43838
[43863]: https://github.com/rust-lang/rust/pull/43863
[43880]: https://github.com/rust-lang/rust/pull/43880
[43911]: https://github.com/rust-lang/rust/pull/43911
[43916]: https://github.com/rust-lang/rust/pull/43916
[43917]: https://github.com/rust-lang/rust/pull/43917
[44204]: https://github.com/rust-lang/rust/pull/44204
[cargo/4123]: https://github.com/rust-lang/cargo/pull/4123
[cargo/4216]: https://github.com/rust-lang/cargo/pull/4216
[cargo/4270]: https://github.com/rust-lang/cargo/pull/4270
[cargo/4335]: https://github.com/rust-lang/cargo/pull/4335
[cargo/4364]: https://github.com/rust-lang/cargo/pull/4364
[cargo/4400]: https://github.com/rust-lang/cargo/pull/4400
[RFC 1969]: https://github.com/rust-lang/rfcs/pull/1969
[info/43880]: https://github.com/rust-lang/rust/issues/44224#issuecomment-330058902
[`std::mem::discriminant`]: https://doc.rust-lang.org/std/mem/fn.discriminant.html
Version 1.20.0 (2017-08-31)
===========================
Language
--------
- [Associated constants are now stabilised.][42809]
- [A lot of macro bugs are now fixed.][42913]
Compiler
--------
- [Struct fields are now properly coerced to the expected field type.][42807]
- [Enabled wasm LLVM backend][42571] WASM can now be built with the
`wasm32-experimental-emscripten` target.
- [Changed some of the error messages to be more helpful.][42033]
- [Add support for RELRO(RELocation Read-Only) for platforms that support
it.][43170]
- [rustc now reports the total number of errors on compilation failure][43015]
previously this was only the number of errors in the pass that failed.
- [Expansion in rustc has been sped up 29x.][42533]
- [added `msp430-none-elf` target.][43099]
- [rustc will now suggest one-argument enum variant to fix type mismatch when
applicable][43178]
- [Fixes backtraces on Redox][43228]
- [rustc now identifies different versions of same crate when absolute paths of
different types match in an error message.][42826]
Libraries
---------
- [Relaxed Debug constraints on `{HashMap,BTreeMap}::{Keys,Values}`.][42854]
- [Impl `PartialEq`, `Eq`, `PartialOrd`, `Ord`, `Debug`, `Hash` for unsized
tuples.][43011]
- [Impl `fmt::{Display, Debug}` for `Ref`, `RefMut`, `MutexGuard`,
`RwLockReadGuard`, `RwLockWriteGuard`][42822]
- [Impl `Clone` for `DefaultHasher`.][42799]
- [Impl `Sync` for `SyncSender`.][42397]
- [Impl `FromStr` for `char`][42271]
- [Fixed how `{f32, f64}::{is_sign_negative, is_sign_positive}` handles
NaN.][42431]
- [allow messages in the `unimplemented!()` macro.][42155]
ie. `unimplemented!("Waiting for 1.21 to be stable")`
- [`pub(restricted)` is now supported in the `thread_local!` macro.][43185]
- [Upgrade to Unicode 10.0.0][42999]
- [Reimplemented `{f32, f64}::{min, max}` in Rust instead of using CMath.][42430]
- [Skip the main thread's manual stack guard on Linux][43072]
- [Iterator::nth for `ops::{Range, RangeFrom}` is now done in O(1) time][43077]
- [`#[repr(align(N))]` attribute max number is now 2^31 - 1.][43097] This was
previously 2^15.
- [`{OsStr, Path}::Display` now avoids allocations where possible][42613]
Stabilized APIs
---------------
- [`CStr::into_c_string`]
- [`CString::as_c_str`]
- [`CString::into_boxed_c_str`]
- [`Chain::get_mut`]
- [`Chain::get_ref`]
- [`Chain::into_inner`]
- [`Option::get_or_insert_with`]
- [`Option::get_or_insert`]
- [`OsStr::into_os_string`]
- [`OsString::into_boxed_os_str`]
- [`Take::get_mut`]
- [`Take::get_ref`]
- [`Utf8Error::error_len`]
- [`char::EscapeDebug`]
- [`char::escape_debug`]
- [`compile_error!`]
- [`f32::from_bits`]
- [`f32::to_bits`]
- [`f64::from_bits`]
- [`f64::to_bits`]
- [`mem::ManuallyDrop`]
- [`slice::sort_unstable_by_key`]
- [`slice::sort_unstable_by`]
- [`slice::sort_unstable`]
- [`str::from_boxed_utf8_unchecked`]
- [`str::as_bytes_mut`]
- [`str::as_bytes_mut`]
- [`str::from_utf8_mut`]
- [`str::from_utf8_unchecked_mut`]
- [`str::get_mut`]
- [`str::get_unchecked_mut`]
- [`str::get_unchecked`]
- [`str::get`]
- [`str::into_boxed_bytes`]
Cargo
-----
- [Cargo API token location moved from `~/.cargo/config` to
`~/.cargo/credentials`.][cargo/3978]
- [Cargo will now build `main.rs` binaries that are in sub-directories of
`src/bin`.][cargo/4214] ie. Having `src/bin/server/main.rs` and
`src/bin/client/main.rs` generates `target/debug/server` and `target/debug/client`
- [You can now specify version of a binary when installed through
`cargo install` using `--vers`.][cargo/4229]
- [Added `--no-fail-fast` flag to cargo to run all benchmarks regardless of
failure.][cargo/4248]
- [Changed the convention around which file is the crate root.][cargo/4259]
- [The `include`/`exclude` property in `Cargo.toml` now accepts gitignore paths
instead of glob patterns][cargo/4270]. Glob patterns are now deprecated.
Compatibility Notes
-------------------
- [Functions with `'static` in their return types will now not be as usable as
if they were using lifetime parameters instead.][42417]
- [The reimplementation of `{f32, f64}::is_sign_{negative, positive}` now
takes the sign of NaN into account where previously didn't.][42430]
[42033]: https://github.com/rust-lang/rust/pull/42033
[42155]: https://github.com/rust-lang/rust/pull/42155
[42271]: https://github.com/rust-lang/rust/pull/42271
[42397]: https://github.com/rust-lang/rust/pull/42397
[42417]: https://github.com/rust-lang/rust/pull/42417
[42430]: https://github.com/rust-lang/rust/pull/42430
[42431]: https://github.com/rust-lang/rust/pull/42431
[42533]: https://github.com/rust-lang/rust/pull/42533
[42571]: https://github.com/rust-lang/rust/pull/42571
[42613]: https://github.com/rust-lang/rust/pull/42613
[42799]: https://github.com/rust-lang/rust/pull/42799
[42807]: https://github.com/rust-lang/rust/pull/42807
[42809]: https://github.com/rust-lang/rust/pull/42809
[42822]: https://github.com/rust-lang/rust/pull/42822
[42826]: https://github.com/rust-lang/rust/pull/42826
[42854]: https://github.com/rust-lang/rust/pull/42854
[42913]: https://github.com/rust-lang/rust/pull/42913
[42999]: https://github.com/rust-lang/rust/pull/42999
[43011]: https://github.com/rust-lang/rust/pull/43011
[43015]: https://github.com/rust-lang/rust/pull/43015
[43072]: https://github.com/rust-lang/rust/pull/43072
[43077]: https://github.com/rust-lang/rust/pull/43077
[43097]: https://github.com/rust-lang/rust/pull/43097
[43099]: https://github.com/rust-lang/rust/pull/43099
[43170]: https://github.com/rust-lang/rust/pull/43170
[43178]: https://github.com/rust-lang/rust/pull/43178
[43185]: https://github.com/rust-lang/rust/pull/43185
[43228]: https://github.com/rust-lang/rust/pull/43228
[cargo/3978]: https://github.com/rust-lang/cargo/pull/3978
[cargo/4214]: https://github.com/rust-lang/cargo/pull/4214
[cargo/4229]: https://github.com/rust-lang/cargo/pull/4229
[cargo/4248]: https://github.com/rust-lang/cargo/pull/4248
[cargo/4259]: https://github.com/rust-lang/cargo/pull/4259
[cargo/4270]: https://github.com/rust-lang/cargo/pull/4270
[`CStr::into_c_string`]: https://doc.rust-lang.org/std/ffi/struct.CStr.html#method.into_c_string
[`CString::as_c_str`]: https://doc.rust-lang.org/std/ffi/struct.CString.html#method.as_c_str
[`CString::into_boxed_c_str`]: https://doc.rust-lang.org/std/ffi/struct.CString.html#method.into_boxed_c_str
[`Chain::get_mut`]: https://doc.rust-lang.org/std/io/struct.Chain.html#method.get_mut
[`Chain::get_ref`]: https://doc.rust-lang.org/std/io/struct.Chain.html#method.get_ref
[`Chain::into_inner`]: https://doc.rust-lang.org/std/io/struct.Chain.html#method.into_inner
[`Option::get_or_insert_with`]: https://doc.rust-lang.org/std/option/enum.Option.html#method.get_or_insert_with
[`Option::get_or_insert`]: https://doc.rust-lang.org/std/option/enum.Option.html#method.get_or_insert
[`OsStr::into_os_string`]: https://doc.rust-lang.org/std/ffi/struct.OsStr.html#method.into_os_string
[`OsString::into_boxed_os_str`]: https://doc.rust-lang.org/std/ffi/struct.OsString.html#method.into_boxed_os_str
[`Take::get_mut`]: https://doc.rust-lang.org/std/io/struct.Take.html#method.get_mut
[`Take::get_ref`]: https://doc.rust-lang.org/std/io/struct.Take.html#method.get_ref
[`Utf8Error::error_len`]: https://doc.rust-lang.org/std/str/struct.Utf8Error.html#method.error_len
[`char::EscapeDebug`]: https://doc.rust-lang.org/std/char/struct.EscapeDebug.html
[`char::escape_debug`]: https://doc.rust-lang.org/std/primitive.char.html#method.escape_debug
[`compile_error!`]: https://doc.rust-lang.org/std/macro.compile_error.html
[`f32::from_bits`]: https://doc.rust-lang.org/std/primitive.f32.html#method.from_bits
[`f32::to_bits`]: https://doc.rust-lang.org/std/primitive.f32.html#method.to_bits
[`f64::from_bits`]: https://doc.rust-lang.org/std/primitive.f64.html#method.from_bits
[`f64::to_bits`]: https://doc.rust-lang.org/std/primitive.f64.html#method.to_bits
[`mem::ManuallyDrop`]: https://doc.rust-lang.org/std/mem/union.ManuallyDrop.html
[`slice::sort_unstable_by_key`]: https://doc.rust-lang.org/std/primitive.slice.html#method.sort_unstable_by_key
[`slice::sort_unstable_by`]: https://doc.rust-lang.org/std/primitive.slice.html#method.sort_unstable_by
[`slice::sort_unstable`]: https://doc.rust-lang.org/std/primitive.slice.html#method.sort_unstable
[`str::from_boxed_utf8_unchecked`]: https://doc.rust-lang.org/std/str/fn.from_boxed_utf8_unchecked.html
[`str::as_bytes_mut`]: https://doc.rust-lang.org/std/primitive.str.html#method.as_bytes_mut
[`str::from_utf8_mut`]: https://doc.rust-lang.org/std/str/fn.from_utf8_mut.html
[`str::from_utf8_unchecked_mut`]: https://doc.rust-lang.org/std/str/fn.from_utf8_unchecked_mut.html
[`str::get_mut`]: https://doc.rust-lang.org/std/primitive.str.html#method.get_mut
[`str::get_unchecked_mut`]: https://doc.rust-lang.org/std/primitive.str.html#method.get_unchecked_mut
[`str::get_unchecked`]: https://doc.rust-lang.org/std/primitive.str.html#method.get_unchecked
[`str::get`]: https://doc.rust-lang.org/std/primitive.str.html#method.get
[`str::into_boxed_bytes`]: https://doc.rust-lang.org/std/primitive.str.html#method.into_boxed_bytes
Version 1.19.0 (2017-07-20)
===========================
Language
--------
- [Numeric fields can now be used for creating tuple structs.][41145] [RFC 1506]
For example `struct Point(u32, u32); let x = Point { 0: 7, 1: 0 };`.
- [Macro recursion limit increased to 1024 from 64.][41676]
- [Added lint for detecting unused macros.][41907]
- [`loop` can now return a value with `break`.][42016] [RFC 1624]
For example: `let x = loop { break 7; };`
- [C compatible `union`s are now available.][42068] [RFC 1444] They can only
contain `Copy` types and cannot have a `Drop` implementation.
Example: `union Foo { bar: u8, baz: usize }`
- [Non capturing closures can now be coerced into `fn`s,][42162] [RFC 1558]
Example: `let foo: fn(u8) -> u8 = |v: u8| { v };`
Compiler
--------
- [Add support for bootstrapping the Rust compiler toolchain on Android.][41370]
- [Change `arm-linux-androideabi` to correspond to the `armeabi`
official ABI.][41656] If you wish to continue targeting the `armeabi-v7a` ABI
you should use `--target armv7-linux-androideabi`.
- [Fixed ICE when removing a source file between compilation sessions.][41873]
- [Minor optimisation of string operations.][42037]
- [Compiler error message is now `aborting due to previous error(s)` instead of
`aborting due to N previous errors`][42150] This was previously inaccurate and
would only count certain kinds of errors.
- [The compiler now supports Visual Studio 2017][42225]
- [The compiler is now built against LLVM 4.0.1 by default][42948]
- [Added a lot][42264] of [new error codes][42302]
- [Added `target-feature=+crt-static` option][37406] [RFC 1721] Which allows
libraries with C Run-time Libraries(CRT) to be statically linked.
- [Fixed various ARM codegen bugs][42740]
Libraries
---------
- [`String` now implements `FromIterator<Cow<'a, str>>` and
`Extend<Cow<'a, str>>`][41449]
- [`Vec` now implements `From<&mut [T]>`][41530]
- [`Box<[u8]>` now implements `From<Box<str>>`][41258]
- [`SplitWhitespace` now implements `Clone`][41659]
- [`[u8]::reverse` is now 5x faster and `[u16]::reverse` is now
1.5x faster][41764]
- [`eprint!` and `eprintln!` macros added to prelude.][41192] Same as the `print!`
macros, but for printing to stderr.
Stabilized APIs
---------------
- [`OsString::shrink_to_fit`]
- [`cmp::Reverse`]
- [`Command::envs`]
- [`thread::ThreadId`]
Cargo
-----
- [Build scripts can now add environment variables to the environment
the crate is being compiled in.
Example: `println!("cargo:rustc-env=FOO=bar");`][cargo/3929]
- [Subcommands now replace the current process rather than spawning a new
child process][cargo/3970]
- [Workspace members can now accept glob file patterns][cargo/3979]
- [Added `--all` flag to the `cargo bench` subcommand to run benchmarks of all
the members in a given workspace.][cargo/3988]
- [Updated `libssh2-sys` to 0.2.6][cargo/4008]
- [Target directory path is now in the cargo metadata][cargo/4022]
- [Cargo no longer checks out a local working directory for the
crates.io index][cargo/4026] This should provide smaller file size for the
registry, and improve cloning times, especially on Windows machines.
- [Added an `--exclude` option for excluding certain packages when using the
`--all` option][cargo/4031]
- [Cargo will now automatically retry when receiving a 5xx error
from crates.io][cargo/4032]
- [The `--features` option now accepts multiple comma or space
delimited values.][cargo/4084]
- [Added support for custom target specific runners][cargo/3954]
Misc
----
- [Added `rust-windbg.cmd`][39983] for loading rust `.natvis` files in the
Windows Debugger.
- [Rust will now release XZ compressed packages][rust-installer/57]
- [rustup will now prefer to download rust packages with
XZ compression][rustup/1100] over GZip packages.
- [Added the ability to escape `#` in rust documentation][41785] By adding
additional `#`'s ie. `##` is now `#`
Compatibility Notes
-------------------
- [`MutexGuard<T>` may only be `Sync` if `T` is `Sync`.][41624]
- [`-Z` flags are now no longer allowed to be used on the stable
compiler.][41751] This has been a warning for a year previous to this.
- [As a result of the `-Z` flag change, the `cargo-check` plugin no
longer works][42844]. Users should migrate to the built-in `check`
command, which has been available since 1.16.
- [Ending a float literal with `._` is now a hard error.
Example: `42._` .][41946]
- [Any use of a private `extern crate` outside of its module is now a
hard error.][36886] This was previously a warning.
- [`use ::self::foo;` is now a hard error.][36888] `self` paths are always
relative while the `::` prefix makes a path absolute, but was ignored and the
path was relative regardless.
- [Floating point constants in match patterns is now a hard error][36890]
This was previously a warning.
- [Struct or enum constants that don't derive `PartialEq` & `Eq` used
match patterns is now a hard error][36891] This was previously a warning.
- [Lifetimes named `'_` are no longer allowed.][36892] This was previously
a warning.
- [From the pound escape, lines consisting of multiple `#`s are
now visible][41785]
- [It is an error to reexport private enum variants][42460]. This is
known to break a number of crates that depend on an older version of
mustache.
- [On Windows, if `VCINSTALLDIR` is set incorrectly, `rustc` will try
to use it to find the linker, and the build will fail where it did
not previously][42607]
[36886]: https://github.com/rust-lang/rust/issues/36886
[36888]: https://github.com/rust-lang/rust/issues/36888
[36890]: https://github.com/rust-lang/rust/issues/36890
[36891]: https://github.com/rust-lang/rust/issues/36891
[36892]: https://github.com/rust-lang/rust/issues/36892
[37406]: https://github.com/rust-lang/rust/issues/37406
[39983]: https://github.com/rust-lang/rust/pull/39983
[41145]: https://github.com/rust-lang/rust/pull/41145
[41192]: https://github.com/rust-lang/rust/pull/41192
[41258]: https://github.com/rust-lang/rust/pull/41258
[41370]: https://github.com/rust-lang/rust/pull/41370
[41449]: https://github.com/rust-lang/rust/pull/41449
[41530]: https://github.com/rust-lang/rust/pull/41530
[41624]: https://github.com/rust-lang/rust/pull/41624
[41656]: https://github.com/rust-lang/rust/pull/41656
[41659]: https://github.com/rust-lang/rust/pull/41659
[41676]: https://github.com/rust-lang/rust/pull/41676
[41751]: https://github.com/rust-lang/rust/pull/41751
[41764]: https://github.com/rust-lang/rust/pull/41764
[41785]: https://github.com/rust-lang/rust/pull/41785
[41873]: https://github.com/rust-lang/rust/pull/41873
[41907]: https://github.com/rust-lang/rust/pull/41907
[41946]: https://github.com/rust-lang/rust/pull/41946
[42016]: https://github.com/rust-lang/rust/pull/42016
[42037]: https://github.com/rust-lang/rust/pull/42037
[42068]: https://github.com/rust-lang/rust/pull/42068
[42150]: https://github.com/rust-lang/rust/pull/42150
[42162]: https://github.com/rust-lang/rust/pull/42162
[42225]: https://github.com/rust-lang/rust/pull/42225
[42264]: https://github.com/rust-lang/rust/pull/42264
[42302]: https://github.com/rust-lang/rust/pull/42302
[42460]: https://github.com/rust-lang/rust/issues/42460
[42607]: https://github.com/rust-lang/rust/issues/42607
[42740]: https://github.com/rust-lang/rust/pull/42740
[42844]: https://github.com/rust-lang/rust/issues/42844
[42948]: https://github.com/rust-lang/rust/pull/42948
[RFC 1444]: https://github.com/rust-lang/rfcs/pull/1444
[RFC 1506]: https://github.com/rust-lang/rfcs/pull/1506
[RFC 1558]: https://github.com/rust-lang/rfcs/pull/1558
[RFC 1624]: https://github.com/rust-lang/rfcs/pull/1624
[RFC 1721]: https://github.com/rust-lang/rfcs/pull/1721
[`Command::envs`]: https://doc.rust-lang.org/std/process/struct.Command.html#method.envs
[`OsString::shrink_to_fit`]: https://doc.rust-lang.org/std/ffi/struct.OsString.html#method.shrink_to_fit
[`cmp::Reverse`]: https://doc.rust-lang.org/std/cmp/struct.Reverse.html
[`thread::ThreadId`]: https://doc.rust-lang.org/std/thread/struct.ThreadId.html
[cargo/3929]: https://github.com/rust-lang/cargo/pull/3929
[cargo/3954]: https://github.com/rust-lang/cargo/pull/3954
[cargo/3970]: https://github.com/rust-lang/cargo/pull/3970
[cargo/3979]: https://github.com/rust-lang/cargo/pull/3979
[cargo/3988]: https://github.com/rust-lang/cargo/pull/3988
[cargo/4008]: https://github.com/rust-lang/cargo/pull/4008
[cargo/4022]: https://github.com/rust-lang/cargo/pull/4022
[cargo/4026]: https://github.com/rust-lang/cargo/pull/4026
[cargo/4031]: https://github.com/rust-lang/cargo/pull/4031
[cargo/4032]: https://github.com/rust-lang/cargo/pull/4032
[cargo/4084]: https://github.com/rust-lang/cargo/pull/4084
[rust-installer/57]: https://github.com/rust-lang/rust-installer/pull/57
[rustup/1100]: https://github.com/rust-lang-nursery/rustup.rs/pull/1100
Version 1.18.0 (2017-06-08)
===========================
Language
--------
- [Stabilize pub(restricted)][40556] `pub` can now accept a module path to
make the item visible to just that module tree. Also accepts the keyword
`crate` to make something public to the whole crate but not users of the
library. Example: `pub(crate) mod utils;`. [RFC 1422].
- [Stabilize `#![windows_subsystem]` attribute][40870] conservative exposure of the
`/SUBSYSTEM` linker flag on Windows platforms. [RFC 1665].
- [Refactor of trait object type parsing][40043] Now `ty` in macros can accept
types like `Write + Send`, trailing `+` are now supported in trait objects,
and better error reporting for trait objects starting with `?Sized`.
- [0e+10 is now a valid floating point literal][40589]
- [Now warns if you bind a lifetime parameter to 'static][40734]
- [Tuples, Enum variant fields, and structs with no `repr` attribute or with
`#[repr(Rust)]` are reordered to minimize padding and produce a smaller
representation in some cases.][40377]
Compiler
--------
- [rustc can now emit mir with `--emit mir`][39891]
- [Improved LLVM IR for trivial functions][40367]
- [Added explanation for E0090(Wrong number of lifetimes are supplied)][40723]
- [rustc compilation is now 15%-20% faster][41469] Thanks to optimisation
opportunities found through profiling
- [Improved backtrace formatting when panicking][38165]
Libraries
---------
- [Specialized `Vec::from_iter` being passed `vec::IntoIter`][40731] if the
iterator hasn't been advanced the original `Vec` is reassembled with no actual
iteration or reallocation.
- [Simplified HashMap Bucket interface][40561] provides performance
improvements for iterating and cloning.
- [Specialize Vec::from_elem to use calloc][40409]
- [Fixed Race condition in fs::create_dir_all][39799]
- [No longer caching stdio on Windows][40516]
- [Optimized insertion sort in slice][40807] insertion sort in some cases
2.50%~ faster and in one case now 12.50% faster.
- [Optimized `AtomicBool::fetch_nand`][41143]
Stabilized APIs
---------------
- [`Child::try_wait`]
- [`HashMap::retain`]
- [`HashSet::retain`]
- [`PeekMut::pop`]
- [`TcpStream::peek`]
- [`UdpSocket::peek`]
- [`UdpSocket::peek_from`]
Cargo
-----
- [Added partial Pijul support][cargo/3842] Pijul is a version control system in Rust.
You can now create new cargo projects with Pijul using `cargo new --vcs pijul`
- [Now always emits build script warnings for crates that fail to build][cargo/3847]
- [Added Android build support][cargo/3885]
- [Added `--bins` and `--tests` flags][cargo/3901] now you can build all programs
of a certain type, for example `cargo build --bins` will build all
binaries.
- [Added support for haiku][cargo/3952]
Misc
----
- [rustdoc can now use pulldown-cmark with the `--enable-commonmark` flag][40338]
- [Added rust-windbg script for better debugging on Windows][39983]
- [Rust now uses the official cross compiler for NetBSD][40612]
- [rustdoc now accepts `#` at the start of files][40828]
- [Fixed jemalloc support for musl][41168]
Compatibility Notes
-------------------
- [Changes to how the `0` flag works in format!][40241] Padding zeroes are now
always placed after the sign if it exists and before the digits. With the `#`
flag the zeroes are placed after the prefix and before the digits.
- [Due to the struct field optimisation][40377], using `transmute` on structs
that have no `repr` attribute or `#[repr(Rust)]` will no longer work. This has
always been undefined behavior, but is now more likely to break in practice.
- [The refactor of trait object type parsing][40043] fixed a bug where `+` was
receiving the wrong priority parsing things like `&for<'a> Tr<'a> + Send` as
`&(for<'a> Tr<'a> + Send)` instead of `(&for<'a> Tr<'a>) + Send`
- [Overlapping inherent `impl`s are now a hard error][40728]
- [`PartialOrd` and `Ord` must agree on the ordering.][41270]
- [`rustc main.rs -o out --emit=asm,llvm-ir`][41085] Now will output
`out.asm` and `out.ll` instead of only one of the filetypes.
- [ calling a function that returns `Self` will no longer work][41805] when
the size of `Self` cannot be statically determined.
- [rustc now builds with a "pthreads" flavour of MinGW for Windows GNU][40805]
this has caused a few regressions namely:
- Changed the link order of local static/dynamic libraries (respecting the
order on given rather than having the compiler reorder).
- Changed how MinGW is linked, native code linked to dynamic libraries
may require manually linking to the gcc support library (for the native
code itself)
[38165]: https://github.com/rust-lang/rust/pull/38165
[39799]: https://github.com/rust-lang/rust/pull/39799
[39891]: https://github.com/rust-lang/rust/pull/39891
[39983]: https://github.com/rust-lang/rust/pull/39983
[40043]: https://github.com/rust-lang/rust/pull/40043
[40241]: https://github.com/rust-lang/rust/pull/40241
[40338]: https://github.com/rust-lang/rust/pull/40338
[40367]: https://github.com/rust-lang/rust/pull/40367
[40377]: https://github.com/rust-lang/rust/pull/40377
[40409]: https://github.com/rust-lang/rust/pull/40409
[40516]: https://github.com/rust-lang/rust/pull/40516
[40556]: https://github.com/rust-lang/rust/pull/40556
[40561]: https://github.com/rust-lang/rust/pull/40561
[40589]: https://github.com/rust-lang/rust/pull/40589
[40612]: https://github.com/rust-lang/rust/pull/40612
[40723]: https://github.com/rust-lang/rust/pull/40723
[40728]: https://github.com/rust-lang/rust/pull/40728
[40731]: https://github.com/rust-lang/rust/pull/40731
[40734]: https://github.com/rust-lang/rust/pull/40734
[40805]: https://github.com/rust-lang/rust/pull/40805
[40807]: https://github.com/rust-lang/rust/pull/40807
[40828]: https://github.com/rust-lang/rust/pull/40828
[40870]: https://github.com/rust-lang/rust/pull/40870
[41085]: https://github.com/rust-lang/rust/pull/41085
[41143]: https://github.com/rust-lang/rust/pull/41143
[41168]: https://github.com/rust-lang/rust/pull/41168
[41270]: https://github.com/rust-lang/rust/issues/41270
[41469]: https://github.com/rust-lang/rust/pull/41469
[41805]: https://github.com/rust-lang/rust/issues/41805
[RFC 1422]: https://github.com/rust-lang/rfcs/blob/master/text/1422-pub-restricted.md
[RFC 1665]: https://github.com/rust-lang/rfcs/blob/master/text/1665-windows-subsystem.md
[`Child::try_wait`]: https://doc.rust-lang.org/std/process/struct.Child.html#method.try_wait
[`HashMap::retain`]: https://doc.rust-lang.org/std/collections/struct.HashMap.html#method.retain
[`HashSet::retain`]: https://doc.rust-lang.org/std/collections/struct.HashSet.html#method.retain
[`PeekMut::pop`]: https://doc.rust-lang.org/std/collections/binary_heap/struct.PeekMut.html#method.pop
[`TcpStream::peek`]: https://doc.rust-lang.org/std/net/struct.TcpStream.html#method.peek
[`UdpSocket::peek_from`]: https://doc.rust-lang.org/std/net/struct.UdpSocket.html#method.peek_from
[`UdpSocket::peek`]: https://doc.rust-lang.org/std/net/struct.UdpSocket.html#method.peek
[cargo/3842]: https://github.com/rust-lang/cargo/pull/3842
[cargo/3847]: https://github.com/rust-lang/cargo/pull/3847
[cargo/3885]: https://github.com/rust-lang/cargo/pull/3885
[cargo/3901]: https://github.com/rust-lang/cargo/pull/3901
[cargo/3952]: https://github.com/rust-lang/cargo/pull/3952
Version 1.17.0 (2017-04-27)
===========================
Language
--------
* [The lifetime of statics and consts defaults to `'static`][39265]. [RFC 1623]
* [Fields of structs may be initialized without duplicating the field/variable
names][39761]. [RFC 1682]
* [`Self` may be included in the `where` clause of `impls`][38864]. [RFC 1647]
* [When coercing to an unsized type lifetimes must be equal][40319]. That is,
there is no subtyping between `T` and `U` when `T: Unsize<U>`. For example,
coercing `&mut [&'a X; N]` to `&mut [&'b X]` requires `'a` be equal to
`'b`. Soundness fix.
* [Values passed to the indexing operator, `[]`, automatically coerce][40166]
* [Static variables may contain references to other statics][40027]
Compiler
--------
* [Exit quickly on only `--emit dep-info`][40336]
* [Make `-C relocation-model` more correctly determine whether the linker
creates a position-independent executable][40245]
* [Add `-C overflow-checks` to directly control whether integer overflow
panics][40037]
* [The rustc type checker now checks items on demand instead of in a single
in-order pass][40008]. This is mostly an internal refactoring in support of
future work, including incremental type checking, but also resolves [RFC
1647], allowing `Self` to appear in `impl` `where` clauses.
* [Optimize vtable loads][39995]
* [Turn off vectorization for Emscripten targets][39990]
* [Provide suggestions for unknown macros imported with `use`][39953]
* [Fix ICEs in path resolution][39939]
* [Strip exception handling code on Emscripten when `panic=abort`][39193]
* [Add clearer error message using `&str + &str`][39116]
Stabilized APIs
---------------
* [`Arc::into_raw`]
* [`Arc::from_raw`]
* [`Arc::ptr_eq`]
* [`Rc::into_raw`]
* [`Rc::from_raw`]
* [`Rc::ptr_eq`]
* [`Ordering::then`]
* [`Ordering::then_with`]
* [`BTreeMap::range`]
* [`BTreeMap::range_mut`]
* [`collections::Bound`]
* [`process::abort`]
* [`ptr::read_unaligned`]
* [`ptr::write_unaligned`]
* [`Result::expect_err`]
* [`Cell::swap`]
* [`Cell::replace`]
* [`Cell::into_inner`]
* [`Cell::take`]
Libraries
---------
* [`BTreeMap` and `BTreeSet` can iterate over ranges][27787]
* [`Cell` can store non-`Copy` types][39793]. [RFC 1651]
* [`String` implements `FromIterator<&char>`][40028]
* `Box` [implements][40009] a number of new conversions:
`From<Box<str>> for String`,
`From<Box<[T]>> for Vec<T>`,
`From<Box<CStr>> for CString`,
`From<Box<OsStr>> for OsString`,
`From<Box<Path>> for PathBuf`,
`Into<Box<str>> for String`,
`Into<Box<[T]>> for Vec<T>`,
`Into<Box<CStr>> for CString`,
`Into<Box<OsStr>> for OsString`,
`Into<Box<Path>> for PathBuf`,
`Default for Box<str>`,
`Default for Box<CStr>`,
`Default for Box<OsStr>`,
`From<&CStr> for Box<CStr>`,
`From<&OsStr> for Box<OsStr>`,
`From<&Path> for Box<Path>`
* [`ffi::FromBytesWithNulError` implements `Error` and `Display`][39960]
* [Specialize `PartialOrd<A> for [A] where A: Ord`][39642]
* [Slightly optimize `slice::sort`][39538]
* [Add `ToString` trait specialization for `Cow<'a, str>` and `String`][39440]
* [`Box<[T]>` implements `From<&[T]> where T: Copy`,
`Box<str>` implements `From<&str>`][39438]
* [`IpAddr` implements `From` for various arrays. `SocketAddr` implements
`From<(I, u16)> where I: Into<IpAddr>`][39372]
* [`format!` estimates the needed capacity before writing a string][39356]
* [Support unprivileged symlink creation in Windows][38921]
* [`PathBuf` implements `Default`][38764]
* [Implement `PartialEq<[A]>` for `VecDeque<A>`][38661]
* [`HashMap` resizes adaptively][38368] to guard against DOS attacks
and poor hash functions.
Cargo
-----
* [Add `cargo check --all`][cargo/3731]
* [Add an option to ignore SSL revocation checking][cargo/3699]
* [Add `cargo run --package`][cargo/3691]
* [Add `required_features`][cargo/3667]
* [Assume `build.rs` is a build script][cargo/3664]
* [Find workspace via `workspace_root` link in containing member][cargo/3562]
Misc
----
* [Documentation is rendered with mdbook instead of the obsolete, in-tree
`rustbook`][39633]
* [The "Unstable Book" documents nightly-only features][ubook]
* [Improve the style of the sidebar in rustdoc output][40265]
* [Configure build correctly on 64-bit CPU's with the armhf ABI][40261]
* [Fix MSP430 breakage due to `i128`][40257]
* [Preliminary Solaris/SPARCv9 support][39903]
* [`rustc` is linked statically on Windows MSVC targets][39837], allowing it to
run without installing the MSVC runtime.
* [`rustdoc --test` includes file names in test names][39788]
* This release includes builds of `std` for `sparc64-unknown-linux-gnu`,
`aarch64-unknown-linux-fuchsia`, and `x86_64-unknown-linux-fuchsia`.
* [Initial support for `aarch64-unknown-freebsd`][39491]
* [Initial support for `i686-unknown-netbsd`][39426]
* [This release no longer includes the old makefile build system][39431]. Rust
is built with a custom build system, written in Rust, and with Cargo.
* [Add Debug implementations for libcollection structs][39002]
* [`TypeId` implements `PartialOrd` and `Ord`][38981]
* [`--test-threads=0` produces an error][38945]
* [`rustup` installs documentation by default][40526]
* [The Rust source includes NatVis visualizations][39843]. These can be used by
WinDbg and Visual Studio to improve the debugging experience.
Compatibility Notes
-------------------
* [Rust 1.17 does not correctly detect the MSVC 2017 linker][38584]. As a
workaround, either use MSVC 2015 or run vcvars.bat.
* [When coercing to an unsized type lifetimes must be equal][40319]. That is,
disallow subtyping between `T` and `U` when `T: Unsize<U>`, e.g. coercing
`&mut [&'a X; N]` to `&mut [&'b X]` requires `'a` be equal to `'b`. Soundness
fix.
* [`format!` and `Display::to_string` panic if an underlying formatting
implementation returns an error][40117]. Previously the error was silently
ignored. It is incorrect for `write_fmt` to return an error when writing
to a string.
* [In-tree crates are verified to be unstable][39851]. Previously, some minor
crates were marked stable and could be accessed from the stable toolchain.
* [Rust git source no longer includes vendored crates][39728]. Those that need
to build with vendored crates should build from release tarballs.
* [Fix inert attributes from `proc_macro_derives`][39572]
* [During crate resolution, rustc prefers a crate in the sysroot if two crates
are otherwise identical][39518]. Unlikely to be encountered outside the Rust
build system.
* [Fixed bugs around how type inference interacts with dead-code][39485]. The
existing code generally ignores the type of dead-code unless a type-hint is
provided; this can cause surprising inference interactions particularly around
defaulting. The new code uniformly ignores the result type of dead-code.
* [Tuple-struct constructors with private fields are no longer visible][38932]
* [Lifetime parameters that do not appear in the arguments are now considered
early-bound][38897], resolving a soundness bug (#[32330]). The
`hr_lifetime_in_assoc_type` future-compatibility lint has been in effect since
April of 2016.
* [rustdoc: fix doctests with non-feature crate attributes][38161]
* [Make transmuting from fn item types to pointer-sized types a hard
error][34198]
[27787]: https://github.com/rust-lang/rust/issues/27787
[32330]: https://github.com/rust-lang/rust/issues/32330
[34198]: https://github.com/rust-lang/rust/pull/34198
[38161]: https://github.com/rust-lang/rust/pull/38161
[38368]: https://github.com/rust-lang/rust/pull/38368
[38584]: https://github.com/rust-lang/rust/issues/38584
[38661]: https://github.com/rust-lang/rust/pull/38661
[38764]: https://github.com/rust-lang/rust/pull/38764
[38864]: https://github.com/rust-lang/rust/issues/38864
[38897]: https://github.com/rust-lang/rust/pull/38897
[38921]: https://github.com/rust-lang/rust/pull/38921
[38932]: https://github.com/rust-lang/rust/pull/38932
[38945]: https://github.com/rust-lang/rust/pull/38945
[38981]: https://github.com/rust-lang/rust/pull/38981
[39002]: https://github.com/rust-lang/rust/pull/39002
[39116]: https://github.com/rust-lang/rust/pull/39116
[39193]: https://github.com/rust-lang/rust/pull/39193
[39265]: https://github.com/rust-lang/rust/pull/39265
[39356]: https://github.com/rust-lang/rust/pull/39356
[39372]: https://github.com/rust-lang/rust/pull/39372
[39426]: https://github.com/rust-lang/rust/pull/39426
[39431]: https://github.com/rust-lang/rust/pull/39431
[39438]: https://github.com/rust-lang/rust/pull/39438
[39440]: https://github.com/rust-lang/rust/pull/39440
[39485]: https://github.com/rust-lang/rust/pull/39485
[39491]: https://github.com/rust-lang/rust/pull/39491
[39518]: https://github.com/rust-lang/rust/pull/39518
[39538]: https://github.com/rust-lang/rust/pull/39538
[39572]: https://github.com/rust-lang/rust/pull/39572
[39633]: https://github.com/rust-lang/rust/pull/39633
[39642]: https://github.com/rust-lang/rust/pull/39642
[39728]: https://github.com/rust-lang/rust/pull/39728
[39761]: https://github.com/rust-lang/rust/pull/39761
[39788]: https://github.com/rust-lang/rust/pull/39788
[39793]: https://github.com/rust-lang/rust/pull/39793
[39837]: https://github.com/rust-lang/rust/pull/39837
[39843]: https://github.com/rust-lang/rust/pull/39843
[39851]: https://github.com/rust-lang/rust/pull/39851
[39903]: https://github.com/rust-lang/rust/pull/39903
[39939]: https://github.com/rust-lang/rust/pull/39939
[39953]: https://github.com/rust-lang/rust/pull/39953
[39960]: https://github.com/rust-lang/rust/pull/39960
[39990]: https://github.com/rust-lang/rust/pull/39990
[39995]: https://github.com/rust-lang/rust/pull/39995
[40008]: https://github.com/rust-lang/rust/pull/40008
[40009]: https://github.com/rust-lang/rust/pull/40009
[40027]: https://github.com/rust-lang/rust/pull/40027
[40028]: https://github.com/rust-lang/rust/pull/40028
[40037]: https://github.com/rust-lang/rust/pull/40037
[40117]: https://github.com/rust-lang/rust/pull/40117
[40166]: https://github.com/rust-lang/rust/pull/40166
[40245]: https://github.com/rust-lang/rust/pull/40245
[40257]: https://github.com/rust-lang/rust/pull/40257
[40261]: https://github.com/rust-lang/rust/pull/40261
[40265]: https://github.com/rust-lang/rust/pull/40265
[40319]: https://github.com/rust-lang/rust/pull/40319
[40336]: https://github.com/rust-lang/rust/pull/40336
[40526]: https://github.com/rust-lang/rust/pull/40526
[RFC 1623]: https://github.com/rust-lang/rfcs/blob/master/text/1623-static.md
[RFC 1647]: https://github.com/rust-lang/rfcs/blob/master/text/1647-allow-self-in-where-clauses.md
[RFC 1651]: https://github.com/rust-lang/rfcs/blob/master/text/1651-movecell.md
[RFC 1682]: https://github.com/rust-lang/rfcs/blob/master/text/1682-field-init-shorthand.md
[`Arc::from_raw`]: https://doc.rust-lang.org/std/sync/struct.Arc.html#method.from_raw
[`Arc::into_raw`]: https://doc.rust-lang.org/std/sync/struct.Arc.html#method.into_raw
[`Arc::ptr_eq`]: https://doc.rust-lang.org/std/sync/struct.Arc.html#method.ptr_eq
[`BTreeMap::range_mut`]: https://doc.rust-lang.org/std/collections/btree_map/struct.BTreeMap.html#method.range_mut
[`BTreeMap::range`]: https://doc.rust-lang.org/std/collections/btree_map/struct.BTreeMap.html#method.range
[`Cell::into_inner`]: https://doc.rust-lang.org/std/cell/struct.Cell.html#method.into_inner
[`Cell::replace`]: https://doc.rust-lang.org/std/cell/struct.Cell.html#method.replace
[`Cell::swap`]: https://doc.rust-lang.org/std/cell/struct.Cell.html#method.swap
[`Cell::take`]: https://doc.rust-lang.org/std/cell/struct.Cell.html#method.take
[`Ordering::then_with`]: https://doc.rust-lang.org/std/cmp/enum.Ordering.html#method.then_with
[`Ordering::then`]: https://doc.rust-lang.org/std/cmp/enum.Ordering.html#method.then
[`Rc::from_raw`]: https://doc.rust-lang.org/std/rc/struct.Rc.html#method.from_raw
[`Rc::into_raw`]: https://doc.rust-lang.org/std/rc/struct.Rc.html#method.into_raw
[`Rc::ptr_eq`]: https://doc.rust-lang.org/std/rc/struct.Rc.html#method.ptr_eq
[`Result::expect_err`]: https://doc.rust-lang.org/std/result/enum.Result.html#method.expect_err
[`collections::Bound`]: https://doc.rust-lang.org/std/collections/enum.Bound.html
[`process::abort`]: https://doc.rust-lang.org/std/process/fn.abort.html
[`ptr::read_unaligned`]: https://doc.rust-lang.org/std/ptr/fn.read_unaligned.html
[`ptr::write_unaligned`]: https://doc.rust-lang.org/std/ptr/fn.write_unaligned.html
[cargo/3562]: https://github.com/rust-lang/cargo/pull/3562
[cargo/3664]: https://github.com/rust-lang/cargo/pull/3664
[cargo/3667]: https://github.com/rust-lang/cargo/pull/3667
[cargo/3691]: https://github.com/rust-lang/cargo/pull/3691
[cargo/3699]: https://github.com/rust-lang/cargo/pull/3699
[cargo/3731]: https://github.com/rust-lang/cargo/pull/3731
[mdbook]: https://crates.io/crates/mdbook
[ubook]: https://doc.rust-lang.org/unstable-book/
Version 1.16.0 (2017-03-16)
===========================
Language
--------
* [The compiler's `dead_code` lint now accounts for type aliases][38051].
* [Uninhabitable enums (those without any variants) no longer permit wildcard
match patterns][38069]
* [Clean up semantics of `self` in an import list][38313]
* [`Self` may appear in `impl` headers][38920]
* [`Self` may appear in struct expressions][39282]
Compiler
--------
* [`rustc` now supports `--emit=metadata`, which causes rustc to emit
a `.rmeta` file containing only crate metadata][38571]. This can be
used by tools like the Rust Language Service to perform
metadata-only builds.
* [Levenshtein based typo suggestions now work in most places, while
previously they worked only for fields and sometimes for local
variables][38927]. Together with the overhaul of "no
resolution"/"unexpected resolution" errors (#[38154]) they result in
large and systematic improvement in resolution diagnostics.
* [Fix `transmute::<T, U>` where `T` requires a bigger alignment than
`U`][38670]
* [rustc: use -Xlinker when specifying an rpath with ',' in it][38798]
* [`rustc` no longer attempts to provide "consider using an explicit
lifetime" suggestions][37057]. They were inaccurate.
Stabilized APIs
---------------
* [`VecDeque::truncate`]
* [`VecDeque::resize`]
* [`String::insert_str`]
* [`Duration::checked_add`]
* [`Duration::checked_sub`]
* [`Duration::checked_div`]
* [`Duration::checked_mul`]
* [`str::replacen`]
* [`str::repeat`]
* [`SocketAddr::is_ipv4`]
* [`SocketAddr::is_ipv6`]
* [`IpAddr::is_ipv4`]
* [`IpAddr::is_ipv6`]
* [`Vec::dedup_by`]
* [`Vec::dedup_by_key`]
* [`Result::unwrap_or_default`]
* [`<*const T>::wrapping_offset`]
* [`<*mut T>::wrapping_offset`]
* `CommandExt::creation_flags`
* [`File::set_permissions`]
* [`String::split_off`]
Libraries
---------
* [`[T]::binary_search` and `[T]::binary_search_by_key` now take
their argument by `Borrow` parameter][37761]
* [All public types in std implement `Debug`][38006]
* [`IpAddr` implements `From<Ipv4Addr>` and `From<Ipv6Addr>`][38327]
* [`Ipv6Addr` implements `From<[u16; 8]>`][38131]
* [Ctrl-Z returns from `Stdin.read()` when reading from the console on
Windows][38274]
* [std: Fix partial writes in `LineWriter`][38062]
* [std: Clamp max read/write sizes on Unix][38062]
* [Use more specific panic message for `&str` slicing errors][38066]
* [`TcpListener::set_only_v6` is deprecated][38304]. This
functionality cannot be achieved in std currently.
* [`writeln!`, like `println!`, now accepts a form with no string
or formatting arguments, to just print a newline][38469]
* [Implement `iter::Sum` and `iter::Product` for `Result`][38580]
* [Reduce the size of static data in `std_unicode::tables`][38781]
* [`char::EscapeDebug`, `EscapeDefault`, `EscapeUnicode`,
`CaseMappingIter`, `ToLowercase`, `ToUppercase`, implement
`Display`][38909]
* [`Duration` implements `Sum`][38712]
* [`String` implements `ToSocketAddrs`][39048]
Cargo
-----
* [The `cargo check` command does a type check of a project without
building it][cargo/3296]
* [crates.io will display CI badges from Travis and AppVeyor, if
specified in Cargo.toml][cargo/3546]
* [crates.io will display categories listed in Cargo.toml][cargo/3301]
* [Compilation profiles accept integer values for `debug`, in addition
to `true` and `false`. These are passed to `rustc` as the value to
`-C debuginfo`][cargo/3534]
* [Implement `cargo --version --verbose`][cargo/3604]
* [All builds now output 'dep-info' build dependencies compatible with
make and ninja][cargo/3557]
* [Build all workspace members with `build --all`][cargo/3511]
* [Document all workspace members with `doc --all`][cargo/3515]
* [Path deps outside workspace are not members][cargo/3443]
Misc
----
* [`rustdoc` has a `--sysroot` argument that, like `rustc`, specifies
the path to the Rust implementation][38589]
* [The `armv7-linux-androideabi` target no longer enables NEON
extensions, per Google's ABI guide][38413]
* [The stock standard library can be compiled for Redox OS][38401]
* [Rust has initial SPARC support][38726]. Tier 3. No builds
available.
* [Rust has experimental support for Nvidia PTX][38559]. Tier 3. No
builds available.
* [Fix backtraces on i686-pc-windows-gnu by disabling FPO][39379]
Compatibility Notes
-------------------
* [Uninhabitable enums (those without any variants) no longer permit wildcard
match patterns][38069]
* In this release, references to uninhabited types can not be
pattern-matched. This was accidentally allowed in 1.15.
* [The compiler's `dead_code` lint now accounts for type aliases][38051].
* [Ctrl-Z returns from `Stdin.read()` when reading from the console on
Windows][38274]
* [Clean up semantics of `self` in an import list][38313]
* Reimplemented lifetime elision. This change was almost entirely compatible
with existing code, but it did close a number of small bugs and loopholes,
as well as being more accepting in some other [cases][41105].
[37057]: https://github.com/rust-lang/rust/pull/37057
[37761]: https://github.com/rust-lang/rust/pull/37761
[38006]: https://github.com/rust-lang/rust/pull/38006
[38051]: https://github.com/rust-lang/rust/pull/38051
[38062]: https://github.com/rust-lang/rust/pull/38062
[38062]: https://github.com/rust-lang/rust/pull/38622
[38066]: https://github.com/rust-lang/rust/pull/38066
[38069]: https://github.com/rust-lang/rust/pull/38069
[38131]: https://github.com/rust-lang/rust/pull/38131
[38154]: https://github.com/rust-lang/rust/pull/38154
[38274]: https://github.com/rust-lang/rust/pull/38274
[38304]: https://github.com/rust-lang/rust/pull/38304
[38313]: https://github.com/rust-lang/rust/pull/38313
[38314]: https://github.com/rust-lang/rust/pull/38314
[38327]: https://github.com/rust-lang/rust/pull/38327
[38401]: https://github.com/rust-lang/rust/pull/38401
[38413]: https://github.com/rust-lang/rust/pull/38413
[38469]: https://github.com/rust-lang/rust/pull/38469
[38559]: https://github.com/rust-lang/rust/pull/38559
[38571]: https://github.com/rust-lang/rust/pull/38571
[38580]: https://github.com/rust-lang/rust/pull/38580
[38589]: https://github.com/rust-lang/rust/pull/38589
[38670]: https://github.com/rust-lang/rust/pull/38670
[38712]: https://github.com/rust-lang/rust/pull/38712
[38726]: https://github.com/rust-lang/rust/pull/38726
[38781]: https://github.com/rust-lang/rust/pull/38781
[38798]: https://github.com/rust-lang/rust/pull/38798
[38909]: https://github.com/rust-lang/rust/pull/38909
[38920]: https://github.com/rust-lang/rust/pull/38920
[38927]: https://github.com/rust-lang/rust/pull/38927
[39048]: https://github.com/rust-lang/rust/pull/39048
[39282]: https://github.com/rust-lang/rust/pull/39282
[39379]: https://github.com/rust-lang/rust/pull/39379
[41105]: https://github.com/rust-lang/rust/issues/41105
[`<*const T>::wrapping_offset`]: https://doc.rust-lang.org/std/primitive.pointer.html#method.wrapping_offset
[`<*mut T>::wrapping_offset`]: https://doc.rust-lang.org/std/primitive.pointer.html#method.wrapping_offset
[`Duration::checked_add`]: https://doc.rust-lang.org/std/time/struct.Duration.html#method.checked_add
[`Duration::checked_div`]: https://doc.rust-lang.org/std/time/struct.Duration.html#method.checked_div
[`Duration::checked_mul`]: https://doc.rust-lang.org/std/time/struct.Duration.html#method.checked_mul
[`Duration::checked_sub`]: https://doc.rust-lang.org/std/time/struct.Duration.html#method.checked_sub
[`File::set_permissions`]: https://doc.rust-lang.org/std/fs/struct.File.html#method.set_permissions
[`IpAddr::is_ipv4`]: https://doc.rust-lang.org/std/net/enum.IpAddr.html#method.is_ipv4
[`IpAddr::is_ipv6`]: https://doc.rust-lang.org/std/net/enum.IpAddr.html#method.is_ipv6
[`Result::unwrap_or_default`]: https://doc.rust-lang.org/std/result/enum.Result.html#method.unwrap_or_default
[`SocketAddr::is_ipv4`]: https://doc.rust-lang.org/std/net/enum.SocketAddr.html#method.is_ipv4
[`SocketAddr::is_ipv6`]: https://doc.rust-lang.org/std/net/enum.SocketAddr.html#method.is_ipv6
[`String::insert_str`]: https://doc.rust-lang.org/std/string/struct.String.html#method.insert_str
[`String::split_off`]: https://doc.rust-lang.org/std/string/struct.String.html#method.split_off
[`Vec::dedup_by_key`]: https://doc.rust-lang.org/std/vec/struct.Vec.html#method.dedup_by_key
[`Vec::dedup_by`]: https://doc.rust-lang.org/std/vec/struct.Vec.html#method.dedup_by
[`VecDeque::resize`]: https://doc.rust-lang.org/std/collections/vec_deque/struct.VecDeque.html#method.resize
[`VecDeque::truncate`]: https://doc.rust-lang.org/std/collections/vec_deque/struct.VecDeque.html#method.truncate
[`str::repeat`]: https://doc.rust-lang.org/std/primitive.str.html#method.repeat
[`str::replacen`]: https://doc.rust-lang.org/std/primitive.str.html#method.replacen
[cargo/3296]: https://github.com/rust-lang/cargo/pull/3296
[cargo/3301]: https://github.com/rust-lang/cargo/pull/3301
[cargo/3443]: https://github.com/rust-lang/cargo/pull/3443
[cargo/3511]: https://github.com/rust-lang/cargo/pull/3511
[cargo/3515]: https://github.com/rust-lang/cargo/pull/3515
[cargo/3534]: https://github.com/rust-lang/cargo/pull/3534
[cargo/3546]: https://github.com/rust-lang/cargo/pull/3546
[cargo/3557]: https://github.com/rust-lang/cargo/pull/3557
[cargo/3604]: https://github.com/rust-lang/cargo/pull/3604
[RFC 1623]: https://github.com/rust-lang/rfcs/blob/master/text/1623-static.md
Version 1.15.1 (2017-02-09)
===========================
* [Fix IntoIter::as_mut_slice's signature][39466]
* [Compile compiler builtins with `-fPIC` on 32-bit platforms][39523]
[39466]: https://github.com/rust-lang/rust/pull/39466
[39523]: https://github.com/rust-lang/rust/pull/39523
Version 1.15.0 (2017-02-02)
===========================
Language
--------
* Basic procedural macros allowing custom `#[derive]`, aka "macros 1.1", are
stable. This allows popular code-generating crates like Serde and Diesel to
work ergonomically. [RFC 1681].
* [Tuple structs may be empty. Unary and empty tuple structs may be instantiated
with curly braces][36868]. Part of [RFC 1506].
* [A number of minor changes to name resolution have been activated][37127].
They add up to more consistent semantics, allowing for future evolution of
Rust macros. Specified in [RFC 1560], see its section on ["changes"] for
details of what is different. The breaking changes here have been transitioned
through the [`legacy_imports`] lint since 1.14, with no known regressions.
* [In `macro_rules`, `path` fragments can now be parsed as type parameter
bounds][38279]
* [`?Sized` can be used in `where` clauses][37791]
* [There is now a limit on the size of monomorphized types and it can be
modified with the `#![type_size_limit]` crate attribute, similarly to
the `#![recursion_limit]` attribute][37789]
Compiler
--------
* [On Windows, the compiler will apply dllimport attributes when linking to
extern functions][37973]. Additional attributes and flags can control which
library kind is linked and its name. [RFC 1717].
* [Rust-ABI symbols are no longer exported from cdylibs][38117]
* [The `--test` flag works with procedural macro crates][38107]
* [Fix `extern "aapcs" fn` ABI][37814]
* [The `-C no-stack-check` flag is deprecated][37636]. It does nothing.
* [The `format!` expander recognizes incorrect `printf` and shell-style
formatting directives and suggests the correct format][37613].
* [Only report one error for all unused imports in an import list][37456]
Compiler Performance
--------------------
* [Avoid unnecessary `mk_ty` calls in `Ty::super_fold_with`][37705]
* [Avoid more unnecessary `mk_ty` calls in `Ty::super_fold_with`][37979]
* [Don't clone in `UnificationTable::probe`][37848]
* [Remove `scope_auxiliary` to cut RSS by 10%][37764]
* [Use small vectors in type walker][37760]
* [Macro expansion performance was improved][37701]
* [Change `HirVec<P<T>>` to `HirVec<T>` in `hir::Expr`][37642]
* [Replace FNV with a faster hash function][37229]
Stabilized APIs
---------------
* [`std::iter::Iterator::min_by`]
* [`std::iter::Iterator::max_by`]
* [`std::os::*::fs::FileExt`]
* [`std::sync::atomic::Atomic*::get_mut`]
* [`std::sync::atomic::Atomic*::into_inner`]
* [`std::vec::IntoIter::as_slice`]
* [`std::vec::IntoIter::as_mut_slice`]
* [`std::sync::mpsc::Receiver::try_iter`]
* [`std::os::unix::process::CommandExt::before_exec`]
* [`std::rc::Rc::strong_count`]
* [`std::rc::Rc::weak_count`]
* [`std::sync::Arc::strong_count`]
* [`std::sync::Arc::weak_count`]
* [`std::char::encode_utf8`]
* [`std::char::encode_utf16`]
* [`std::cell::Ref::clone`]
* [`std::io::Take::into_inner`]
Libraries
---------
* [The standard sorting algorithm has been rewritten for dramatic performance
improvements][38192]. It is a hybrid merge sort, drawing influences from
Timsort. Previously it was a naive merge sort.
* [`Iterator::nth` no longer has a `Sized` bound][38134]
* [`Extend<&T>` is specialized for `Vec` where `T: Copy`][38182] to improve
performance.
* [`chars().count()` is much faster][37888] and so are [`chars().last()`
and `char_indices().last()`][37882]
* [Fix ARM Objective-C ABI in `std::env::args`][38146]
* [Chinese characters display correctly in `fmt::Debug`][37855]
* [Derive `Default` for `Duration`][37699]
* [Support creation of anonymous pipes on WinXP/2k][37677]
* [`mpsc::RecvTimeoutError` implements `Error`][37527]
* [Don't pass overlapped handles to processes][38835]
Cargo
-----
* [In this release, Cargo build scripts no longer have access to the `OUT_DIR`
environment variable at build time via `env!("OUT_DIR")`][cargo/3368]. They
should instead check the variable at runtime with `std::env`. That the value
was set at build time was a bug, and incorrect when cross-compiling. This
change is known to cause breakage.
* [Add `--all` flag to `cargo test`][cargo/3221]
* [Compile statically against the MSVC CRT][cargo/3363]
* [Mix feature flags into fingerprint/metadata shorthash][cargo/3102]
* [Link OpenSSL statically on OSX][cargo/3311]
* [Apply new fingerprinting to build dir outputs][cargo/3310]
* [Test for bad path overrides with summaries][cargo/3336]
* [Require `cargo install --vers` to take a semver version][cargo/3338]
* [Fix retrying crate downloads for network errors][cargo/3348]
* [Implement string lookup for `build.rustflags` config key][cargo/3356]
* [Emit more info on --message-format=json][cargo/3319]
* [Assume `build.rs` in the same directory as `Cargo.toml` is a build script][cargo/3361]
* [Don't ignore errors in workspace manifest][cargo/3409]
* [Fix `--message-format JSON` when rustc emits non-JSON warnings][cargo/3410]
Tooling
-------
* [Test runners (binaries built with `--test`) now support a `--list` argument
that lists the tests it contains][38185]
* [Test runners now support a `--exact` argument that makes the test filter
match exactly, instead of matching only a substring of the test name][38181]
* [rustdoc supports a `--playground-url` flag][37763]
* [rustdoc provides more details about `#[should_panic]` errors][37749]
Misc
----
* [The Rust build system is now written in Rust][37817]. The Makefiles may
continue to be used in this release by passing `--disable-rustbuild` to the
configure script, but they will be deleted soon. Note that the new build
system uses a different on-disk layout that will likely affect any scripts
building Rust.
* [Rust supports i686-unknown-openbsd][38086]. Tier 3 support. No testing or
releases.
* [Rust supports the MSP430][37627]. Tier 3 support. No testing or releases.
* [Rust supports the ARMv5TE architecture][37615]. Tier 3 support. No testing or
releases.
Compatibility Notes
-------------------
* [A number of minor changes to name resolution have been activated][37127].
They add up to more consistent semantics, allowing for future evolution of
Rust macros. Specified in [RFC 1560], see its section on ["changes"] for
details of what is different. The breaking changes here have been transitioned
through the [`legacy_imports`] lint since 1.14, with no known regressions.
* [In this release, Cargo build scripts no longer have access to the `OUT_DIR`
environment variable at build time via `env!("OUT_DIR")`][cargo/3368]. They
should instead check the variable at runtime with `std::env`. That the value
was set at build time was a bug, and incorrect when cross-compiling. This
change is known to cause breakage.
* [Higher-ranked lifetimes are no longer allowed to appear _only_ in associated
types][33685]. The [`hr_lifetime_in_assoc_type` lint] has been a warning since
1.10 and is now an error by default. It will become a hard error in the near
future.
* [The semantics relating modules to file system directories are changing in
minor ways][37602]. This is captured in the new `legacy_directory_ownership`
lint, which is a warning in this release, and will become a hard error in the
future.
* [Rust-ABI symbols are no longer exported from cdylibs][38117]
* [Once `Peekable` peeks a `None` it will return that `None` without re-querying
the underlying iterator][37834]
["changes"]: https://github.com/rust-lang/rfcs/blob/master/text/1560-name-resolution.md#changes-to-name-resolution-rules
[33685]: https://github.com/rust-lang/rust/issues/33685
[36868]: https://github.com/rust-lang/rust/pull/36868
[37127]: https://github.com/rust-lang/rust/pull/37127
[37229]: https://github.com/rust-lang/rust/pull/37229
[37456]: https://github.com/rust-lang/rust/pull/37456
[37527]: https://github.com/rust-lang/rust/pull/37527
[37602]: https://github.com/rust-lang/rust/pull/37602
[37613]: https://github.com/rust-lang/rust/pull/37613
[37615]: https://github.com/rust-lang/rust/pull/37615
[37636]: https://github.com/rust-lang/rust/pull/37636
[37627]: https://github.com/rust-lang/rust/pull/37627
[37642]: https://github.com/rust-lang/rust/pull/37642
[37677]: https://github.com/rust-lang/rust/pull/37677
[37699]: https://github.com/rust-lang/rust/pull/37699
[37701]: https://github.com/rust-lang/rust/pull/37701
[37705]: https://github.com/rust-lang/rust/pull/37705
[37749]: https://github.com/rust-lang/rust/pull/37749
[37760]: https://github.com/rust-lang/rust/pull/37760
[37763]: https://github.com/rust-lang/rust/pull/37763
[37764]: https://github.com/rust-lang/rust/pull/37764
[37789]: https://github.com/rust-lang/rust/pull/37789
[37791]: https://github.com/rust-lang/rust/pull/37791
[37814]: https://github.com/rust-lang/rust/pull/37814
[37817]: https://github.com/rust-lang/rust/pull/37817
[37834]: https://github.com/rust-lang/rust/pull/37834
[37848]: https://github.com/rust-lang/rust/pull/37848
[37855]: https://github.com/rust-lang/rust/pull/37855
[37882]: https://github.com/rust-lang/rust/pull/37882
[37888]: https://github.com/rust-lang/rust/pull/37888
[37973]: https://github.com/rust-lang/rust/pull/37973
[37979]: https://github.com/rust-lang/rust/pull/37979
[38086]: https://github.com/rust-lang/rust/pull/38086
[38107]: https://github.com/rust-lang/rust/pull/38107
[38117]: https://github.com/rust-lang/rust/pull/38117
[38134]: https://github.com/rust-lang/rust/pull/38134
[38146]: https://github.com/rust-lang/rust/pull/38146
[38181]: https://github.com/rust-lang/rust/pull/38181
[38182]: https://github.com/rust-lang/rust/pull/38182
[38185]: https://github.com/rust-lang/rust/pull/38185
[38192]: https://github.com/rust-lang/rust/pull/38192
[38279]: https://github.com/rust-lang/rust/pull/38279
[38835]: https://github.com/rust-lang/rust/pull/38835
[RFC 1492]: https://github.com/rust-lang/rfcs/blob/master/text/1492-dotdot-in-patterns.md
[RFC 1506]: https://github.com/rust-lang/rfcs/blob/master/text/1506-adt-kinds.md
[RFC 1560]: https://github.com/rust-lang/rfcs/blob/master/text/1560-name-resolution.md
[RFC 1681]: https://github.com/rust-lang/rfcs/blob/master/text/1681-macros-1.1.md
[RFC 1717]: https://github.com/rust-lang/rfcs/blob/master/text/1717-dllimport.md
[`hr_lifetime_in_assoc_type` lint]: https://github.com/rust-lang/rust/issues/33685
[`legacy_imports`]: https://github.com/rust-lang/rust/pull/38271
[cargo/3102]: https://github.com/rust-lang/cargo/pull/3102
[cargo/3221]: https://github.com/rust-lang/cargo/pull/3221
[cargo/3310]: https://github.com/rust-lang/cargo/pull/3310
[cargo/3311]: https://github.com/rust-lang/cargo/pull/3311
[cargo/3319]: https://github.com/rust-lang/cargo/pull/3319
[cargo/3336]: https://github.com/rust-lang/cargo/pull/3336
[cargo/3338]: https://github.com/rust-lang/cargo/pull/3338
[cargo/3348]: https://github.com/rust-lang/cargo/pull/3348
[cargo/3356]: https://github.com/rust-lang/cargo/pull/3356
[cargo/3361]: https://github.com/rust-lang/cargo/pull/3361
[cargo/3363]: https://github.com/rust-lang/cargo/pull/3363
[cargo/3368]: https://github.com/rust-lang/cargo/issues/3368
[cargo/3409]: https://github.com/rust-lang/cargo/pull/3409
[cargo/3410]: https://github.com/rust-lang/cargo/pull/3410
[`std::iter::Iterator::min_by`]: https://doc.rust-lang.org/std/iter/trait.Iterator.html#method.min_by
[`std::iter::Iterator::max_by`]: https://doc.rust-lang.org/std/iter/trait.Iterator.html#method.max_by
[`std::os::*::fs::FileExt`]: https://doc.rust-lang.org/std/os/unix/fs/trait.FileExt.html
[`std::sync::atomic::Atomic*::get_mut`]: https://doc.rust-lang.org/std/sync/atomic/struct.AtomicU8.html#method.get_mut
[`std::sync::atomic::Atomic*::into_inner`]: https://doc.rust-lang.org/std/sync/atomic/struct.AtomicU8.html#method.into_inner
[`std::vec::IntoIter::as_slice`]: https://doc.rust-lang.org/std/vec/struct.IntoIter.html#method.as_slice
[`std::vec::IntoIter::as_mut_slice`]: https://doc.rust-lang.org/std/vec/struct.IntoIter.html#method.as_mut_slice
[`std::sync::mpsc::Receiver::try_iter`]: https://doc.rust-lang.org/std/sync/mpsc/struct.Receiver.html#method.try_iter
[`std::os::unix::process::CommandExt::before_exec`]: https://doc.rust-lang.org/std/os/unix/process/trait.CommandExt.html#tymethod.before_exec
[`std::rc::Rc::strong_count`]: https://doc.rust-lang.org/std/rc/struct.Rc.html#method.strong_count
[`std::rc::Rc::weak_count`]: https://doc.rust-lang.org/std/rc/struct.Rc.html#method.weak_count
[`std::sync::Arc::strong_count`]: https://doc.rust-lang.org/std/sync/struct.Arc.html#method.strong_count
[`std::sync::Arc::weak_count`]: https://doc.rust-lang.org/std/sync/struct.Arc.html#method.weak_count
[`std::char::encode_utf8`]: https://doc.rust-lang.org/std/primitive.char.html#method.encode_utf8
[`std::char::encode_utf16`]: https://doc.rust-lang.org/std/primitive.char.html#method.encode_utf16
[`std::cell::Ref::clone`]: https://doc.rust-lang.org/std/cell/struct.Ref.html#method.clone
[`std::io::Take::into_inner`]: https://doc.rust-lang.org/std/io/struct.Take.html#method.into_inner
Version 1.14.0 (2016-12-22)
===========================
Language
--------
* [`..` matches multiple tuple fields in enum variants, structs
and tuples][36843]. [RFC 1492].
* [Safe `fn` items can be coerced to `unsafe fn` pointers][37389]
* [`use *` and `use ::*` both glob-import from the crate root][37367]
* [It's now possible to call a `Vec<Box<Fn()>>` without explicit
dereferencing][36822]
Compiler
--------
* [Mark enums with non-zero discriminant as non-zero][37224]
* [Lower-case `static mut` names are linted like other
statics and consts][37162]
* [Fix ICE on some macros in const integer positions
(e.g. `[u8; m!()]`)][36819]
* [Improve error message and snippet for "did you mean `x`"][36798]
* [Add a panic-strategy field to the target specification][36794]
* [Include LLVM version in `--version --verbose`][37200]
Compile-time Optimizations
--------------------------
* [Improve macro expansion performance][37569]
* [Shrink `Expr_::ExprInlineAsm`][37445]
* [Replace all uses of SHA-256 with BLAKE2b][37439]
* [Reduce the number of bytes hashed by `IchHasher`][37427]
* [Avoid more allocations when compiling html5ever][37373]
* [Use `SmallVector` in `CombineFields::instantiate`][37322]
* [Avoid some allocations in the macro parser][37318]
* [Use a faster deflate setting][37298]
* [Add `ArrayVec` and `AccumulateVec` to reduce heap allocations
during interning of slices][37270]
* [Optimize `write_metadata`][37267]
* [Don't process obligation forest cycles when stalled][37231]
* [Avoid many `CrateConfig` clones][37161]
* [Optimize `Substs::super_fold_with`][37108]
* [Optimize `ObligationForest`'s `NodeState` handling][36993]
* [Speed up `plug_leaks`][36917]
Libraries
---------
* [`println!()`, with no arguments, prints newline][36825].
Previously, an empty string was required to achieve the same.
* [`Wrapping` impls standard binary and unary operators, as well as
the `Sum` and `Product` iterators][37356]
* [Implement `From<Cow<str>> for String` and `From<Cow<[T]>> for
Vec<T>`][37326]
* [Improve `fold` performance for `chain`, `cloned`, `map`, and
`VecDeque` iterators][37315]
* [Improve `SipHasher` performance on small values][37312]
* [Add Iterator trait TrustedLen to enable better FromIterator /
Extend][37306]
* [Expand `.zip()` specialization to `.map()` and `.cloned()`][37230]
* [`ReadDir` implements `Debug`][37221]
* [Implement `RefUnwindSafe` for atomic types][37178]
* [Specialize `Vec::extend` to `Vec::extend_from_slice`][37094]
* [Avoid allocations in `Decoder::read_str`][37064]
* [`io::Error` implements `From<io::ErrorKind>`][37037]
* [Impl `Debug` for raw pointers to unsized data][36880]
* [Don't reuse `HashMap` random seeds][37470]
* [The internal memory layout of `HashMap` is more cache-friendly, for
significant improvements in some operations][36692]
* [`HashMap` uses less memory on 32-bit architectures][36595]
* [Impl `Add<{str, Cow<str>}>` for `Cow<str>`][36430]
Cargo
-----
* [Expose rustc cfg values to build scripts][cargo/3243]
* [Allow cargo to work with read-only `CARGO_HOME`][cargo/3259]
* [Fix passing --features when testing multiple packages][cargo/3280]
* [Use a single profile set per workspace][cargo/3249]
* [Load `replace` sections from lock files][cargo/3220]
* [Ignore `panic` configuration for test/bench profiles][cargo/3175]
Tooling
-------
* [rustup is the recommended Rust installation method][1.14rustup]
* This release includes host (rustc) builds for Linux on MIPS, PowerPC, and
S390x. These are [tier 2] platforms and may have major defects. Follow the
instructions on the website to install, or add the targets to an existing
installation with `rustup target add`. The new target triples are:
- `mips-unknown-linux-gnu`
- `mipsel-unknown-linux-gnu`
- `mips64-unknown-linux-gnuabi64`
- `mips64el-unknown-linux-gnuabi64 `
- `powerpc-unknown-linux-gnu`
- `powerpc64-unknown-linux-gnu`
- `powerpc64le-unknown-linux-gnu`
- `s390x-unknown-linux-gnu `
* This release includes target (std) builds for ARM Linux running MUSL
libc. These are [tier 2] platforms and may have major defects. Add the
following triples to an existing rustup installation with `rustup target add`:
- `arm-unknown-linux-musleabi`
- `arm-unknown-linux-musleabihf`
- `armv7-unknown-linux-musleabihf`
* This release includes [experimental support for WebAssembly][1.14wasm], via
the `wasm32-unknown-emscripten` target. This target is known to have major
defects. Please test, report, and fix.
* rustup no longer installs documentation by default. Run `rustup
component add rust-docs` to install.
* [Fix line stepping in debugger][37310]
* [Enable line number debuginfo in releases][37280]
Misc
----
* [Disable jemalloc on aarch64/powerpc/mips][37392]
* [Add support for Fuchsia OS][37313]
* [Detect local-rebuild by only MAJOR.MINOR version][37273]
Compatibility Notes
-------------------
* [A number of forward-compatibility lints used by the compiler
to gradually introduce language changes have been converted
to deny by default][36894]:
- ["use of inaccessible extern crate erroneously allowed"][36886]
- ["type parameter default erroneously allowed in invalid location"][36887]
- ["detects super or self keywords at the beginning of global path"][36888]
- ["two overlapping inherent impls define an item with the same name
were erroneously allowed"][36889]
- ["floating-point constants cannot be used in patterns"][36890]
- ["constants of struct or enum type can only be used in a pattern if
the struct or enum has `#[derive(PartialEq, Eq)]`"][36891]
- ["lifetimes or labels named `'_` were erroneously allowed"][36892]
* [Prohibit patterns in trait methods without bodies][37378]
* [The atomic `Ordering` enum may not be matched exhaustively][37351]
* [Future-proofing `#[no_link]` breaks some obscure cases][37247]
* [The `$crate` macro variable is accepted in fewer locations][37213]
* [Impls specifying extra region requirements beyond the trait
they implement are rejected][37167]
* [Enums may not be unsized][37111]. Unsized enums are intended to
work but never have. For now they are forbidden.
* [Enforce the shadowing restrictions from RFC 1560 for today's macros][36767]
[tier 2]: https://forge.rust-lang.org/platform-support.html
[1.14rustup]: https://internals.rust-lang.org/t/beta-testing-rustup-rs/3316/204
[1.14wasm]: https://users.rust-lang.org/t/compiling-to-the-web-with-rust-and-emscripten/7627
[36430]: https://github.com/rust-lang/rust/pull/36430
[36595]: https://github.com/rust-lang/rust/pull/36595
[36595]: https://github.com/rust-lang/rust/pull/36595
[36692]: https://github.com/rust-lang/rust/pull/36692
[36767]: https://github.com/rust-lang/rust/pull/36767
[36794]: https://github.com/rust-lang/rust/pull/36794
[36798]: https://github.com/rust-lang/rust/pull/36798
[36819]: https://github.com/rust-lang/rust/pull/36819
[36822]: https://github.com/rust-lang/rust/pull/36822
[36825]: https://github.com/rust-lang/rust/pull/36825
[36843]: https://github.com/rust-lang/rust/pull/36843
[36880]: https://github.com/rust-lang/rust/pull/36880
[36886]: https://github.com/rust-lang/rust/issues/36886
[36887]: https://github.com/rust-lang/rust/issues/36887
[36888]: https://github.com/rust-lang/rust/issues/36888
[36889]: https://github.com/rust-lang/rust/issues/36889
[36890]: https://github.com/rust-lang/rust/issues/36890
[36891]: https://github.com/rust-lang/rust/issues/36891
[36892]: https://github.com/rust-lang/rust/issues/36892
[36894]: https://github.com/rust-lang/rust/pull/36894
[36917]: https://github.com/rust-lang/rust/pull/36917
[36993]: https://github.com/rust-lang/rust/pull/36993
[37037]: https://github.com/rust-lang/rust/pull/37037
[37064]: https://github.com/rust-lang/rust/pull/37064
[37094]: https://github.com/rust-lang/rust/pull/37094
[37108]: https://github.com/rust-lang/rust/pull/37108
[37111]: https://github.com/rust-lang/rust/pull/37111
[37161]: https://github.com/rust-lang/rust/pull/37161
[37162]: https://github.com/rust-lang/rust/pull/37162
[37167]: https://github.com/rust-lang/rust/pull/37167
[37178]: https://github.com/rust-lang/rust/pull/37178
[37200]: https://github.com/rust-lang/rust/pull/37200
[37213]: https://github.com/rust-lang/rust/pull/37213
[37221]: https://github.com/rust-lang/rust/pull/37221
[37224]: https://github.com/rust-lang/rust/pull/37224
[37230]: https://github.com/rust-lang/rust/pull/37230
[37231]: https://github.com/rust-lang/rust/pull/37231
[37247]: https://github.com/rust-lang/rust/pull/37247
[37267]: https://github.com/rust-lang/rust/pull/37267
[37270]: https://github.com/rust-lang/rust/pull/37270
[37273]: https://github.com/rust-lang/rust/pull/37273
[37280]: https://github.com/rust-lang/rust/pull/37280
[37298]: https://github.com/rust-lang/rust/pull/37298
[37306]: https://github.com/rust-lang/rust/pull/37306
[37310]: https://github.com/rust-lang/rust/pull/37310
[37312]: https://github.com/rust-lang/rust/pull/37312
[37313]: https://github.com/rust-lang/rust/pull/37313
[37315]: https://github.com/rust-lang/rust/pull/37315
[37318]: https://github.com/rust-lang/rust/pull/37318
[37322]: https://github.com/rust-lang/rust/pull/37322
[37326]: https://github.com/rust-lang/rust/pull/37326
[37351]: https://github.com/rust-lang/rust/pull/37351
[37356]: https://github.com/rust-lang/rust/pull/37356
[37367]: https://github.com/rust-lang/rust/pull/37367
[37373]: https://github.com/rust-lang/rust/pull/37373
[37378]: https://github.com/rust-lang/rust/pull/37378
[37389]: https://github.com/rust-lang/rust/pull/37389
[37392]: https://github.com/rust-lang/rust/pull/37392
[37427]: https://github.com/rust-lang/rust/pull/37427
[37439]: https://github.com/rust-lang/rust/pull/37439
[37445]: https://github.com/rust-lang/rust/pull/37445
[37470]: https://github.com/rust-lang/rust/pull/37470
[37569]: https://github.com/rust-lang/rust/pull/37569
[RFC 1492]: https://github.com/rust-lang/rfcs/blob/master/text/1492-dotdot-in-patterns.md
[cargo/3175]: https://github.com/rust-lang/cargo/pull/3175
[cargo/3220]: https://github.com/rust-lang/cargo/pull/3220
[cargo/3243]: https://github.com/rust-lang/cargo/pull/3243
[cargo/3249]: https://github.com/rust-lang/cargo/pull/3249
[cargo/3259]: https://github.com/rust-lang/cargo/pull/3259
[cargo/3280]: https://github.com/rust-lang/cargo/pull/3280
Version 1.13.0 (2016-11-10)
===========================
Language
--------
* [Stabilize the `?` operator][36995]. `?` is a simple way to propagate
errors, like the `try!` macro, described in [RFC 0243].
* [Stabilize macros in type position][36014]. Described in [RFC 873].
* [Stabilize attributes on statements][36995]. Described in [RFC 0016].
* [Fix `#[derive]` for empty tuple structs/variants][35728]
* [Fix lifetime rules for 'if' conditions][36029]
* [Avoid loading and parsing unconfigured non-inline modules][36482]
Compiler
--------
* [Add the `-C link-arg` argument][36574]
* [Remove the old AST-based backend from rustc_trans][35764]
* [Don't enable NEON by default on armv7 Linux][35814]
* [Fix debug line number info for macro expansions][35238]
* [Do not emit "class method" debuginfo for types that are not
DICompositeType][36008]
* [Warn about multiple conflicting #[repr] hints][34623]
* [When sizing DST, don't double-count nested struct prefixes][36351]
* [Default RUST_MIN_STACK to 16MiB for now][36505]
* [Improve rlib metadata format][36551]. Reduces rlib size significantly.
* [Reject macros with empty repetitions to avoid infinite loop][36721]
* [Expand macros without recursing to avoid stack overflows][36214]
Diagnostics
-----------
* [Replace macro backtraces with labeled local uses][35702]
* [Improve error message for misplaced doc comments][33922]
* [Buffer unix and lock windows to prevent message interleaving][35975]
* [Update lifetime errors to specifically note temporaries][36171]
* [Special case a few colors for Windows][36178]
* [Suggest `use self` when such an import resolves][36289]
* [Be more specific when type parameter shadows primitive type][36338]
* Many minor improvements
Compile-time Optimizations
--------------------------
* [Compute and cache HIR hashes at beginning][35854]
* [Don't hash types in loan paths][36004]
* [Cache projections in trans][35761]
* [Optimize the parser's last token handling][36527]
* [Only instantiate #[inline] functions in codegen units referencing
them][36524]. This leads to big improvements in cases where crates export
define many inline functions without using them directly.
* [Lazily allocate TypedArena's first chunk][36592]
* [Don't allocate during default HashSet creation][36734]
Stabilized APIs
---------------
* [`checked_abs`]
* [`wrapping_abs`]
* [`overflowing_abs`]
* [`RefCell::try_borrow`]
* [`RefCell::try_borrow_mut`]
Libraries
---------
* [Add `assert_ne!` and `debug_assert_ne!`][35074]
* [Make `vec_deque::Drain`, `hash_map::Drain`, and `hash_set::Drain`
covariant][35354]
* [Implement `AsRef<[T]>` for `std::slice::Iter`][35559]
* [Implement `Debug` for `std::vec::IntoIter`][35707]
* [`CString`: avoid excessive growth just to 0-terminate][35871]
* [Implement `CoerceUnsized` for `{Cell, RefCell, UnsafeCell}`][35627]
* [Use arc4rand on FreeBSD][35884]
* [memrchr: Correct aligned offset computation][35969]
* [Improve Demangling of Rust Symbols][36059]
* [Use monotonic time in condition variables][35048]
* [Implement `Debug` for `std::path::{Components,Iter}`][36101]
* [Implement conversion traits for `char`][35755]
* [Fix illegal instruction caused by overflow in channel cloning][36104]
* [Zero first byte of CString on drop][36264]
* [Inherit overflow checks for sum and product][36372]
* [Add missing Eq implementations][36423]
* [Implement `Debug` for `DirEntry`][36631]
* [When `getaddrinfo` returns `EAI_SYSTEM` retrieve actual error from
`errno`][36754]
* [`SipHasher`] is deprecated. Use [`DefaultHasher`].
* [Implement more traits for `std::io::ErrorKind`][35911]
* [Optimize BinaryHeap bounds checking][36072]
* [Work around pointer aliasing issue in `Vec::extend_from_slice`,
`extend_with_element`][36355]
* [Fix overflow checking in unsigned pow()][34942]
Cargo
-----
* This release includes security fixes to both curl and OpenSSL.
* [Fix transitive doctests when panic=abort][cargo/3021]
* [Add --all-features flag to cargo][cargo/3038]
* [Reject path-based dependencies in `cargo package`][cargo/3060]
* [Don't parse the home directory more than once][cargo/3078]
* [Don't try to generate Cargo.lock on empty workspaces][cargo/3092]
* [Update OpenSSL to 1.0.2j][cargo/3121]
* [Add license and license_file to cargo metadata output][cargo/3110]
* [Make crates-io registry URL optional in config; ignore all changes to
source.crates-io][cargo/3089]
* [Don't download dependencies from other platforms][cargo/3123]
* [Build transitive dev-dependencies when needed][cargo/3125]
* [Add support for per-target rustflags in .cargo/config][cargo/3157]
* [Avoid updating registry when adding existing deps][cargo/3144]
* [Warn about path overrides that won't work][cargo/3136]
* [Use workspaces during `cargo install`][cargo/3146]
* [Leak mspdbsrv.exe processes on Windows][cargo/3162]
* [Add --message-format flag][cargo/3000]
* [Pass target environment for rustdoc][cargo/3205]
* [Use `CommandExt::exec` for `cargo run` on Unix][cargo/2818]
* [Update curl and curl-sys][cargo/3241]
* [Call rustdoc test with the correct cfg flags of a package][cargo/3242]
Tooling
-------
* [rustdoc: Add the `--sysroot` argument][36586]
* [rustdoc: Fix a couple of issues with the search results][35655]
* [rustdoc: remove the `!` from macro URLs and titles][35234]
* [gdb: Fix pretty-printing special-cased Rust types][35585]
* [rustdoc: Filter more incorrect methods inherited through Deref][36266]
Misc
----
* [Remove unmaintained style guide][35124]
* [Add s390x support][36369]
* [Initial work at Haiku OS support][36727]
* [Add mips-uclibc targets][35734]
* [Crate-ify compiler-rt into compiler-builtins][35021]
* [Add rustc version info (git hash + date) to dist tarball][36213]
* Many documentation improvements
Compatibility Notes
-------------------
* [`SipHasher`] is deprecated. Use [`DefaultHasher`].
* [Deny (by default) transmuting from fn item types to pointer-sized
types][34923]. Continuing the long transition to zero-sized fn items,
per [RFC 401].
* [Fix `#[derive]` for empty tuple structs/variants][35728].
Part of [RFC 1506].
* [Issue deprecation warnings for safe accesses to extern statics][36173]
* [Fix lifetime rules for 'if' conditions][36029].
* [Inherit overflow checks for sum and product][36372].
* [Forbid user-defined macros named "macro_rules"][36730].
[33922]: https://github.com/rust-lang/rust/pull/33922
[34623]: https://github.com/rust-lang/rust/pull/34623
[34923]: https://github.com/rust-lang/rust/pull/34923
[34942]: https://github.com/rust-lang/rust/pull/34942
[34982]: https://github.com/rust-lang/rust/pull/34982
[35021]: https://github.com/rust-lang/rust/pull/35021
[35048]: https://github.com/rust-lang/rust/pull/35048
[35074]: https://github.com/rust-lang/rust/pull/35074
[35124]: https://github.com/rust-lang/rust/pull/35124
[35234]: https://github.com/rust-lang/rust/pull/35234
[35238]: https://github.com/rust-lang/rust/pull/35238
[35354]: https://github.com/rust-lang/rust/pull/35354
[35559]: https://github.com/rust-lang/rust/pull/35559
[35585]: https://github.com/rust-lang/rust/pull/35585
[35627]: https://github.com/rust-lang/rust/pull/35627
[35655]: https://github.com/rust-lang/rust/pull/35655
[35702]: https://github.com/rust-lang/rust/pull/35702
[35707]: https://github.com/rust-lang/rust/pull/35707
[35728]: https://github.com/rust-lang/rust/pull/35728
[35734]: https://github.com/rust-lang/rust/pull/35734
[35755]: https://github.com/rust-lang/rust/pull/35755
[35761]: https://github.com/rust-lang/rust/pull/35761
[35764]: https://github.com/rust-lang/rust/pull/35764
[35814]: https://github.com/rust-lang/rust/pull/35814
[35854]: https://github.com/rust-lang/rust/pull/35854
[35871]: https://github.com/rust-lang/rust/pull/35871
[35884]: https://github.com/rust-lang/rust/pull/35884
[35911]: https://github.com/rust-lang/rust/pull/35911
[35969]: https://github.com/rust-lang/rust/pull/35969
[35975]: https://github.com/rust-lang/rust/pull/35975
[36004]: https://github.com/rust-lang/rust/pull/36004
[36008]: https://github.com/rust-lang/rust/pull/36008
[36014]: https://github.com/rust-lang/rust/pull/36014
[36029]: https://github.com/rust-lang/rust/pull/36029
[36059]: https://github.com/rust-lang/rust/pull/36059
[36072]: https://github.com/rust-lang/rust/pull/36072
[36101]: https://github.com/rust-lang/rust/pull/36101
[36104]: https://github.com/rust-lang/rust/pull/36104
[36171]: https://github.com/rust-lang/rust/pull/36171
[36173]: https://github.com/rust-lang/rust/pull/36173
[36178]: https://github.com/rust-lang/rust/pull/36178
[36213]: https://github.com/rust-lang/rust/pull/36213
[36214]: https://github.com/rust-lang/rust/pull/36214
[36264]: https://github.com/rust-lang/rust/pull/36264
[36266]: https://github.com/rust-lang/rust/pull/36266
[36289]: https://github.com/rust-lang/rust/pull/36289
[36338]: https://github.com/rust-lang/rust/pull/36338
[36351]: https://github.com/rust-lang/rust/pull/36351
[36355]: https://github.com/rust-lang/rust/pull/36355
[36369]: https://github.com/rust-lang/rust/pull/36369
[36372]: https://github.com/rust-lang/rust/pull/36372
[36423]: https://github.com/rust-lang/rust/pull/36423
[36482]: https://github.com/rust-lang/rust/pull/36482
[36505]: https://github.com/rust-lang/rust/pull/36505
[36524]: https://github.com/rust-lang/rust/pull/36524
[36527]: https://github.com/rust-lang/rust/pull/36527
[36551]: https://github.com/rust-lang/rust/pull/36551
[36574]: https://github.com/rust-lang/rust/pull/36574
[36586]: https://github.com/rust-lang/rust/pull/36586
[36592]: https://github.com/rust-lang/rust/pull/36592
[36631]: https://github.com/rust-lang/rust/pull/36631
[36639]: https://github.com/rust-lang/rust/pull/36639
[36721]: https://github.com/rust-lang/rust/pull/36721
[36727]: https://github.com/rust-lang/rust/pull/36727
[36730]: https://github.com/rust-lang/rust/pull/36730
[36734]: https://github.com/rust-lang/rust/pull/36734
[36754]: https://github.com/rust-lang/rust/pull/36754
[36995]: https://github.com/rust-lang/rust/pull/36995
[RFC 0016]: https://github.com/rust-lang/rfcs/blob/master/text/0016-more-attributes.md
[RFC 0243]: https://github.com/rust-lang/rfcs/blob/master/text/0243-trait-based-exception-handling.md
[RFC 1506]: https://github.com/rust-lang/rfcs/blob/master/text/1506-adt-kinds.md
[RFC 401]: https://github.com/rust-lang/rfcs/blob/master/text/0401-coercions.md
[RFC 873]: https://github.com/rust-lang/rfcs/blob/master/text/0873-type-macros.md
[cargo/2818]: https://github.com/rust-lang/cargo/pull/2818
[cargo/3000]: https://github.com/rust-lang/cargo/pull/3000
[cargo/3021]: https://github.com/rust-lang/cargo/pull/3021
[cargo/3038]: https://github.com/rust-lang/cargo/pull/3038
[cargo/3060]: https://github.com/rust-lang/cargo/pull/3060
[cargo/3078]: https://github.com/rust-lang/cargo/pull/3078
[cargo/3089]: https://github.com/rust-lang/cargo/pull/3089
[cargo/3092]: https://github.com/rust-lang/cargo/pull/3092
[cargo/3110]: https://github.com/rust-lang/cargo/pull/3110
[cargo/3121]: https://github.com/rust-lang/cargo/pull/3121
[cargo/3123]: https://github.com/rust-lang/cargo/pull/3123
[cargo/3125]: https://github.com/rust-lang/cargo/pull/3125
[cargo/3136]: https://github.com/rust-lang/cargo/pull/3136
[cargo/3144]: https://github.com/rust-lang/cargo/pull/3144
[cargo/3146]: https://github.com/rust-lang/cargo/pull/3146
[cargo/3157]: https://github.com/rust-lang/cargo/pull/3157
[cargo/3162]: https://github.com/rust-lang/cargo/pull/3162
[cargo/3205]: https://github.com/rust-lang/cargo/pull/3205
[cargo/3241]: https://github.com/rust-lang/cargo/pull/3241
[cargo/3242]: https://github.com/rust-lang/cargo/pull/3242
[rustup]: https://www.rustup.rs
[`checked_abs`]: https://doc.rust-lang.org/std/primitive.i32.html#method.checked_abs
[`wrapping_abs`]: https://doc.rust-lang.org/std/primitive.i32.html#method.wrapping_abs
[`overflowing_abs`]: https://doc.rust-lang.org/std/primitive.i32.html#method.overflowing_abs
[`RefCell::try_borrow`]: https://doc.rust-lang.org/std/cell/struct.RefCell.html#method.try_borrow
[`RefCell::try_borrow_mut`]: https://doc.rust-lang.org/std/cell/struct.RefCell.html#method.try_borrow_mut
[`SipHasher`]: https://doc.rust-lang.org/std/hash/struct.SipHasher.html
[`DefaultHasher`]: https://doc.rust-lang.org/std/collections/hash_map/struct.DefaultHasher.html
Version 1.12.1 (2016-10-20)
===========================
Regression Fixes
----------------
* [ICE: 'rustc' panicked at 'assertion failed: concrete_substs.is_normalized_for_trans()' #36381][36381]
* [Confusion with double negation and booleans][36856]
* [rustc 1.12.0 fails with SIGSEGV in release mode (syn crate 0.8.0)][36875]
* [Rustc 1.12.0 Windows build of `ethcore` crate fails with LLVM error][36924]
* [1.12.0: High memory usage when linking in release mode with debug info][36926]
* [Corrupted memory after updated to 1.12][36936]
* ["Let NullaryConstructor = something;" causes internal compiler error: "tried to overwrite interned AdtDef"][37026]
* [Fix ICE: inject bitcast if types mismatch for invokes/calls/stores][37112]
* [debuginfo: Handle spread_arg case in MIR-trans in a more stable way.][37153]
[36381]: https://github.com/rust-lang/rust/issues/36381
[36856]: https://github.com/rust-lang/rust/issues/36856
[36875]: https://github.com/rust-lang/rust/issues/36875
[36924]: https://github.com/rust-lang/rust/issues/36924
[36926]: https://github.com/rust-lang/rust/issues/36926
[36936]: https://github.com/rust-lang/rust/issues/36936
[37026]: https://github.com/rust-lang/rust/issues/37026
[37112]: https://github.com/rust-lang/rust/issues/37112
[37153]: https://github.com/rust-lang/rust/issues/37153
Version 1.12.0 (2016-09-29)
===========================
Highlights
----------
* [`rustc` translates code to LLVM IR via its own "middle" IR (MIR)](https://github.com/rust-lang/rust/pull/34096).
This translation pass is far simpler than the previous AST->LLVM pass, and
creates opportunities to perform new optimizations directly on the MIR. It
was previously described [on the Rust blog](https://blog.rust-lang.org/2016/04/19/MIR.html).
* [`rustc` presents a new, more readable error format, along with
machine-readable JSON error output for use by IDEs](https://github.com/rust-lang/rust/pull/35401).
Most common editors supporting Rust have been updated to work with it. It was
previously described [on the Rust blog](https://blog.rust-lang.org/2016/08/10/Shape-of-errors-to-come.html).
Compiler
--------
* [`rustc` translates code to LLVM IR via its own "middle" IR (MIR)](https://github.com/rust-lang/rust/pull/34096).
This translation pass is far simpler than the previous AST->LLVM pass, and
creates opportunities to perform new optimizations directly on the MIR. It
was previously described [on the Rust blog](https://blog.rust-lang.org/2016/04/19/MIR.html).
* [Print the Rust target name, not the LLVM target name, with
`--print target-list`](https://github.com/rust-lang/rust/pull/35489)
* [The computation of `TypeId` is correct in some cases where it was previously
producing inconsistent results](https://github.com/rust-lang/rust/pull/35267)
* [The `mips-unknown-linux-gnu` target uses hardware floating point by default](https://github.com/rust-lang/rust/pull/34910)
* [The `rustc` arguments, `--print target-cpus`, `--print target-features`,
`--print relocation-models`, and `--print code-models` print the available
options to the `-C target-cpu`, `-C target-feature`, `-C relocation-model` and
`-C code-model` code generation arguments](https://github.com/rust-lang/rust/pull/34845)
* [`rustc` supports three new MUSL targets on ARM: `arm-unknown-linux-musleabi`,
`arm-unknown-linux-musleabihf`, and `armv7-unknown-linux-musleabihf`](https://github.com/rust-lang/rust/pull/35060).
These targets produce statically-linked binaries. There are no binary release
builds yet though.
Diagnostics
-----------
* [`rustc` presents a new, more readable error format, along with
machine-readable JSON error output for use by IDEs](https://github.com/rust-lang/rust/pull/35401).
Most common editors supporting Rust have been updated to work with it. It was
previously described [on the Rust blog](https://blog.rust-lang.org/2016/08/10/Shape-of-errors-to-come.html).
* [In error descriptions, references are now described in plain English,
instead of as "&-ptr"](https://github.com/rust-lang/rust/pull/35611)
* [In error type descriptions, unknown numeric types are named `{integer}` or
`{float}` instead of `_`](https://github.com/rust-lang/rust/pull/35080)
* [`rustc` emits a clearer error when inner attributes follow a doc comment](https://github.com/rust-lang/rust/pull/34676)
Language
--------
* [`macro_rules!` invocations can be made within `macro_rules!` invocations](https://github.com/rust-lang/rust/pull/34925)
* [`macro_rules!` meta-variables are hygienic](https://github.com/rust-lang/rust/pull/35453)
* [`macro_rules!` `tt` matchers can be reparsed correctly, making them much more
useful](https://github.com/rust-lang/rust/pull/34908)
* [`macro_rules!` `stmt` matchers correctly consume the entire contents when
inside non-braces invocations](https://github.com/rust-lang/rust/pull/34886)
* [Semicolons are properly required as statement delimiters inside
`macro_rules!` invocations](https://github.com/rust-lang/rust/pull/34660)
* [`cfg_attr` works on `path` attributes](https://github.com/rust-lang/rust/pull/34546)
Stabilized APIs
---------------
* [`Cell::as_ptr`](https://doc.rust-lang.org/std/cell/struct.Cell.html#method.as_ptr)
* [`RefCell::as_ptr`](https://doc.rust-lang.org/std/cell/struct.RefCell.html#method.as_ptr)
* [`IpAddr::is_unspecified`](https://doc.rust-lang.org/std/net/enum.IpAddr.html#method.is_unspecified)
* [`IpAddr::is_loopback`](https://doc.rust-lang.org/std/net/enum.IpAddr.html#method.is_loopback)
* [`IpAddr::is_multicast`](https://doc.rust-lang.org/std/net/enum.IpAddr.html#method.is_multicast)
* [`Ipv4Addr::is_unspecified`](https://doc.rust-lang.org/std/net/struct.Ipv4Addr.html#method.is_unspecified)
* [`Ipv6Addr::octets`](https://doc.rust-lang.org/std/net/struct.Ipv6Addr.html#method.octets)
* [`LinkedList::contains`](https://doc.rust-lang.org/std/collections/linked_list/struct.LinkedList.html#method.contains)
* [`VecDeque::contains`](https://doc.rust-lang.org/std/collections/vec_deque/struct.VecDeque.html#method.contains)
* [`ExitStatusExt::from_raw`](https://doc.rust-lang.org/std/os/unix/process/trait.ExitStatusExt.html#tymethod.from_raw).
Both on Unix and Windows.
* [`Receiver::recv_timeout`](https://doc.rust-lang.org/std/sync/mpsc/struct.Receiver.html#method.recv_timeout)
* [`RecvTimeoutError`](https://doc.rust-lang.org/std/sync/mpsc/enum.RecvTimeoutError.html)
* [`BinaryHeap::peek_mut`](https://doc.rust-lang.org/std/collections/binary_heap/struct.BinaryHeap.html#method.peek_mut)
* [`PeekMut`](https://doc.rust-lang.org/std/collections/binary_heap/struct.PeekMut.html)
* [`iter::Product`](https://doc.rust-lang.org/std/iter/trait.Product.html)
* [`iter::Sum`](https://doc.rust-lang.org/std/iter/trait.Sum.html)
* [`OccupiedEntry::remove_entry`](https://doc.rust-lang.org/std/collections/btree_map/struct.OccupiedEntry.html#method.remove_entry)
* [`VacantEntry::into_key`](https://doc.rust-lang.org/std/collections/btree_map/struct.VacantEntry.html#method.into_key)
Libraries
---------
* [The `format!` macro and friends now allow a single argument to be formatted
in multiple styles](https://github.com/rust-lang/rust/pull/33642)
* [The lifetime bounds on `[T]::binary_search_by` and
`[T]::binary_search_by_key` have been adjusted to be more flexible](https://github.com/rust-lang/rust/pull/34762)
* [`Option` implements `From` for its contained type](https://github.com/rust-lang/rust/pull/34828)
* [`Cell`, `RefCell` and `UnsafeCell` implement `From` for their contained type](https://github.com/rust-lang/rust/pull/35392)
* [`RwLock` panics if the reader count overflows](https://github.com/rust-lang/rust/pull/35378)
* [`vec_deque::Drain`, `hash_map::Drain` and `hash_set::Drain` are covariant](https://github.com/rust-lang/rust/pull/35354)
* [`vec::Drain` and `binary_heap::Drain` are covariant](https://github.com/rust-lang/rust/pull/34951)
* [`Cow<str>` implements `FromIterator` for `char`, `&str` and `String`](https://github.com/rust-lang/rust/pull/35064)
* [Sockets on Linux are correctly closed in subprocesses via `SOCK_CLOEXEC`](https://github.com/rust-lang/rust/pull/34946)
* [`hash_map::Entry`, `hash_map::VacantEntry` and `hash_map::OccupiedEntry`
implement `Debug`](https://github.com/rust-lang/rust/pull/34937)
* [`btree_map::Entry`, `btree_map::VacantEntry` and `btree_map::OccupiedEntry`
implement `Debug`](https://github.com/rust-lang/rust/pull/34885)
* [`String` implements `AddAssign`](https://github.com/rust-lang/rust/pull/34890)
* [Variadic `extern fn` pointers implement the `Clone`, `PartialEq`, `Eq`,
`PartialOrd`, `Ord`, `Hash`, `fmt::Pointer`, and `fmt::Debug` traits](https://github.com/rust-lang/rust/pull/34879)
* [`FileType` implements `Debug`](https://github.com/rust-lang/rust/pull/34757)
* [References to `Mutex` and `RwLock` are unwind-safe](https://github.com/rust-lang/rust/pull/34756)
* [`mpsc::sync_channel` `Receiver`s return any available message before
reporting a disconnect](https://github.com/rust-lang/rust/pull/34731)
* [Unicode definitions have been updated to 9.0](https://github.com/rust-lang/rust/pull/34599)
* [`env` iterators implement `DoubleEndedIterator`](https://github.com/rust-lang/rust/pull/33312)
Cargo
-----
* [Support local mirrors of registries](https://github.com/rust-lang/cargo/pull/2857)
* [Add support for command aliases](https://github.com/rust-lang/cargo/pull/2679)
* [Allow `opt-level="s"` / `opt-level="z"` in profile overrides](https://github.com/rust-lang/cargo/pull/3007)
* [Make `cargo doc --open --target` work as expected](https://github.com/rust-lang/cargo/pull/2988)
* [Speed up noop registry updates](https://github.com/rust-lang/cargo/pull/2974)
* [Update OpenSSL](https://github.com/rust-lang/cargo/pull/2971)
* [Fix `--panic=abort` with plugins](https://github.com/rust-lang/cargo/pull/2954)
* [Always pass `-C metadata` to the compiler](https://github.com/rust-lang/cargo/pull/2946)
* [Fix depending on git repos with workspaces](https://github.com/rust-lang/cargo/pull/2938)
* [Add a `--lib` flag to `cargo new`](https://github.com/rust-lang/cargo/pull/2921)
* [Add `http.cainfo` for custom certs](https://github.com/rust-lang/cargo/pull/2917)
* [Indicate the compilation profile after compiling](https://github.com/rust-lang/cargo/pull/2909)
* [Allow enabling features for dependencies with `--features`](https://github.com/rust-lang/cargo/pull/2876)
* [Add `--jobs` flag to `cargo package`](https://github.com/rust-lang/cargo/pull/2867)
* [Add `--dry-run` to `cargo publish`](https://github.com/rust-lang/cargo/pull/2849)
* [Add support for `RUSTDOCFLAGS`](https://github.com/rust-lang/cargo/pull/2794)
Performance
-----------
* [`panic::catch_unwind` is more optimized](https://github.com/rust-lang/rust/pull/35444)
* [`panic::catch_unwind` no longer accesses thread-local storage on entry](https://github.com/rust-lang/rust/pull/34866)
Tooling
-------
* [Test binaries now support a `--test-threads` argument to specify the number
of threads used to run tests, and which acts the same as the
`RUST_TEST_THREADS` environment variable](https://github.com/rust-lang/rust/pull/35414)
* [The test runner now emits a warning when tests run over 60 seconds](https://github.com/rust-lang/rust/pull/35405)
* [rustdoc: Fix methods in search results](https://github.com/rust-lang/rust/pull/34752)
* [`rust-lldb` warns about unsupported versions of LLDB](https://github.com/rust-lang/rust/pull/34646)
* [Rust releases now come with source packages that can be installed by rustup
via `rustup component add rust-src`](https://github.com/rust-lang/rust/pull/34366).
The resulting source code can be used by tools and IDES, located in the
sysroot under `lib/rustlib/src`.
Misc
----
* [The compiler can now be built against LLVM 3.9](https://github.com/rust-lang/rust/pull/35594)
* Many minor improvements to the documentation.
* [The Rust exception handling "personality" routine is now written in Rust](https://github.com/rust-lang/rust/pull/34832)
Compatibility Notes
-------------------
* [When printing Windows `OsStr`s, unpaired surrogate codepoints are escaped
with the lowercase format instead of the uppercase](https://github.com/rust-lang/rust/pull/35084)
* [When formatting strings, if "precision" is specified, the "fill",
"align" and "width" specifiers are no longer ignored](https://github.com/rust-lang/rust/pull/34544)
* [The `Debug` impl for strings no longer escapes all non-ASCII characters](https://github.com/rust-lang/rust/pull/34485)
Version 1.11.0 (2016-08-18)
===========================
Language
--------
* [`cfg_attr` works on `path` attributes](https://github.com/rust-lang/rust/pull/34546)
* [Support nested `cfg_attr` attributes](https://github.com/rust-lang/rust/pull/34216)
* [Allow statement-generating braced macro invocations at the end of blocks](https://github.com/rust-lang/rust/pull/34436)
* [Macros can be expanded inside of trait definitions](https://github.com/rust-lang/rust/pull/34213)
* [`#[macro_use]` works properly when it is itself expanded from a macro](https://github.com/rust-lang/rust/pull/34032)
Stabilized APIs
---------------
* [`BinaryHeap::append`](https://doc.rust-lang.org/std/collections/binary_heap/struct.BinaryHeap.html#method.append)
* [`BTreeMap::append`](https://doc.rust-lang.org/std/collections/btree_map/struct.BTreeMap.html#method.append)
* [`BTreeMap::split_off`](https://doc.rust-lang.org/std/collections/btree_map/struct.BTreeMap.html#method.split_off)
* [`BTreeSet::append`](https://doc.rust-lang.org/std/collections/btree_set/struct.BTreeSet.html#method.append)
* [`BTreeSet::split_off`](https://doc.rust-lang.org/std/collections/btree_set/struct.BTreeSet.html#method.split_off)
* [`f32::to_degrees`](https://doc.rust-lang.org/std/primitive.f32.html#method.to_degrees)
(in libcore - previously stabilized in libstd)
* [`f32::to_radians`](https://doc.rust-lang.org/std/primitive.f32.html#method.to_radians)
(in libcore - previously stabilized in libstd)
* [`f64::to_degrees`](https://doc.rust-lang.org/std/primitive.f64.html#method.to_degrees)
(in libcore - previously stabilized in libstd)
* [`f64::to_radians`](https://doc.rust-lang.org/std/primitive.f64.html#method.to_radians)
(in libcore - previously stabilized in libstd)
* [`Iterator::sum`](https://doc.rust-lang.org/std/iter/trait.Iterator.html#method.sum)
* [`Iterator::product`](https://doc.rust-lang.org/std/iter/trait.Iterator.html#method.sum)
* [`Cell::get_mut`](https://doc.rust-lang.org/std/cell/struct.Cell.html#method.get_mut)
* [`RefCell::get_mut`](https://doc.rust-lang.org/std/cell/struct.RefCell.html#method.get_mut)
Libraries
---------
* [The `thread_local!` macro supports multiple definitions in a single
invocation, and can apply attributes](https://github.com/rust-lang/rust/pull/34077)
* [`Cow` implements `Default`](https://github.com/rust-lang/rust/pull/34305)
* [`Wrapping` implements binary, octal, lower-hex and upper-hex
`Display` formatting](https://github.com/rust-lang/rust/pull/34190)
* [The range types implement `Hash`](https://github.com/rust-lang/rust/pull/34180)
* [`lookup_host` ignores unknown address types](https://github.com/rust-lang/rust/pull/34067)
* [`assert_eq!` accepts a custom error message, like `assert!` does](https://github.com/rust-lang/rust/pull/33976)
* [The main thread is now called "main" instead of "&lt;main&gt;"](https://github.com/rust-lang/rust/pull/33803)
Cargo
-----
* [Disallow specifying features of transitive deps](https://github.com/rust-lang/cargo/pull/2821)
* [Add color support for Windows consoles](https://github.com/rust-lang/cargo/pull/2804)
* [Fix `harness = false` on `[lib]` sections](https://github.com/rust-lang/cargo/pull/2795)
* [Don't panic when `links` contains a '.'](https://github.com/rust-lang/cargo/pull/2787)
* [Build scripts can emit warnings](https://github.com/rust-lang/cargo/pull/2630),
and `-vv` prints warnings for all crates.
* [Ignore file locks on OS X NFS mounts](https://github.com/rust-lang/cargo/pull/2720)
* [Don't warn about `package.metadata` keys](https://github.com/rust-lang/cargo/pull/2668).
This provides room for expansion by arbitrary tools.
* [Add support for cdylib crate types](https://github.com/rust-lang/cargo/pull/2741)
* [Prevent publishing crates when files are dirty](https://github.com/rust-lang/cargo/pull/2781)
* [Don't fetch all crates on clean](https://github.com/rust-lang/cargo/pull/2704)
* [Propagate --color option to rustc](https://github.com/rust-lang/cargo/pull/2779)
* [Fix `cargo doc --open` on Windows](https://github.com/rust-lang/cargo/pull/2780)
* [Improve autocompletion](https://github.com/rust-lang/cargo/pull/2772)
* [Configure colors of stderr as well as stdout](https://github.com/rust-lang/cargo/pull/2739)
Performance
-----------
* [Caching projections speeds up type check dramatically for some
workloads](https://github.com/rust-lang/rust/pull/33816)
* [The default `HashMap` hasher is SipHash 1-3 instead of SipHash 2-4](https://github.com/rust-lang/rust/pull/33940)
This hasher is faster, but is believed to provide sufficient
protection from collision attacks.
* [Comparison of `Ipv4Addr` is 10x faster](https://github.com/rust-lang/rust/pull/33891)
Rustdoc
-------
* [Fix empty implementation section on some module pages](https://github.com/rust-lang/rust/pull/34536)
* [Fix inlined renamed reexports in import lists](https://github.com/rust-lang/rust/pull/34479)
* [Fix search result layout for enum variants and struct fields](https://github.com/rust-lang/rust/pull/34477)
* [Fix issues with source links to external crates](https://github.com/rust-lang/rust/pull/34387)
* [Fix redirect pages for renamed reexports](https://github.com/rust-lang/rust/pull/34245)
Tooling
-------
* [rustc is better at finding the MSVC toolchain](https://github.com/rust-lang/rust/pull/34492)
* [When emitting debug info, rustc emits frame pointers for closures,
shims and glue, as it does for all other functions](https://github.com/rust-lang/rust/pull/33909)
* [rust-lldb warns about unsupported versions of LLDB](https://github.com/rust-lang/rust/pull/34646)
* Many more errors have been given error codes and extended
explanations
* API documentation continues to be improved, with many new examples
Misc
----
* [rustc no longer hangs when dependencies recursively re-export
submodules](https://github.com/rust-lang/rust/pull/34542)
* [rustc requires LLVM 3.7+](https://github.com/rust-lang/rust/pull/34104)
* [The 'How Safe and Unsafe Interact' chapter of The Rustonomicon was
rewritten](https://github.com/rust-lang/rust/pull/33895)
* [rustc support 16-bit pointer sizes](https://github.com/rust-lang/rust/pull/33460).
No targets use this yet, but it works toward AVR support.
Compatibility Notes
-------------------
* [`const`s and `static`s may not have unsized types](https://github.com/rust-lang/rust/pull/34443)
* [The new follow-set rules that place restrictions on `macro_rules!`
in order to ensure syntax forward-compatibility have been enabled](https://github.com/rust-lang/rust/pull/33982)
This was an [amendment to RFC 550](https://github.com/rust-lang/rfcs/pull/1384),
and has been a warning since 1.10.
* [`cfg` attribute process has been refactored to fix various bugs](https://github.com/rust-lang/rust/pull/33706).
This causes breakage in some corner cases.
Version 1.10.0 (2016-07-07)
===========================
Language
--------
* [Allow `concat_idents!` in type positions as well as in expression
positions](https://github.com/rust-lang/rust/pull/33735).
* [`Copy` types are required to have a trivial implementation of `Clone`](https://github.com/rust-lang/rust/pull/33420).
[RFC 1521](https://github.com/rust-lang/rfcs/blob/master/text/1521-copy-clone-semantics.md).
* [Single-variant enums support the `#[repr(..)]` attribute](https://github.com/rust-lang/rust/pull/33355).
* [Fix `#[derive(RustcEncodable)]` in the presence of other `encode` methods](https://github.com/rust-lang/rust/pull/32908).
* [`panic!` can be converted to a runtime abort with the
`-C panic=abort` flag](https://github.com/rust-lang/rust/pull/32900).
[RFC 1513](https://github.com/rust-lang/rfcs/blob/master/text/1513-less-unwinding.md).
* [Add a new crate type, 'cdylib'](https://github.com/rust-lang/rust/pull/33553).
cdylibs are dynamic libraries suitable for loading by non-Rust hosts.
[RFC 1510](https://github.com/rust-lang/rfcs/blob/master/text/1510-rdylib.md).
Note that Cargo does not yet directly support cdylibs.
Stabilized APIs
---------------
* `os::windows::fs::OpenOptionsExt::access_mode`
* `os::windows::fs::OpenOptionsExt::share_mode`
* `os::windows::fs::OpenOptionsExt::custom_flags`
* `os::windows::fs::OpenOptionsExt::attributes`
* `os::windows::fs::OpenOptionsExt::security_qos_flags`
* `os::unix::fs::OpenOptionsExt::custom_flags`
* [`sync::Weak::new`](http://doc.rust-lang.org/alloc/arc/struct.Weak.html#method.new)
* `Default for sync::Weak`
* [`panic::set_hook`](http://doc.rust-lang.org/std/panic/fn.set_hook.html)
* [`panic::take_hook`](http://doc.rust-lang.org/std/panic/fn.take_hook.html)
* [`panic::PanicInfo`](http://doc.rust-lang.org/std/panic/struct.PanicInfo.html)
* [`panic::PanicInfo::payload`](http://doc.rust-lang.org/std/panic/struct.PanicInfo.html#method.payload)
* [`panic::PanicInfo::location`](http://doc.rust-lang.org/std/panic/struct.PanicInfo.html#method.location)
* [`panic::Location`](http://doc.rust-lang.org/std/panic/struct.Location.html)
* [`panic::Location::file`](http://doc.rust-lang.org/std/panic/struct.Location.html#method.file)
* [`panic::Location::line`](http://doc.rust-lang.org/std/panic/struct.Location.html#method.line)
* [`ffi::CStr::from_bytes_with_nul`](http://doc.rust-lang.org/std/ffi/struct.CStr.html#method.from_bytes_with_nul)
* [`ffi::CStr::from_bytes_with_nul_unchecked`](http://doc.rust-lang.org/std/ffi/struct.CStr.html#method.from_bytes_with_nul_unchecked)
* [`ffi::FromBytesWithNulError`](http://doc.rust-lang.org/std/ffi/struct.FromBytesWithNulError.html)
* [`fs::Metadata::modified`](http://doc.rust-lang.org/std/fs/struct.Metadata.html#method.modified)
* [`fs::Metadata::accessed`](http://doc.rust-lang.org/std/fs/struct.Metadata.html#method.accessed)
* [`fs::Metadata::created`](http://doc.rust-lang.org/std/fs/struct.Metadata.html#method.created)
* `sync::atomic::Atomic{Usize,Isize,Bool,Ptr}::compare_exchange`
* `sync::atomic::Atomic{Usize,Isize,Bool,Ptr}::compare_exchange_weak`
* `collections::{btree,hash}_map::{Occupied,Vacant,}Entry::key`
* `os::unix::net::{UnixStream, UnixListener, UnixDatagram, SocketAddr}`
* [`SocketAddr::is_unnamed`](http://doc.rust-lang.org/std/os/unix/net/struct.SocketAddr.html#method.is_unnamed)
* [`SocketAddr::as_pathname`](http://doc.rust-lang.org/std/os/unix/net/struct.SocketAddr.html#method.as_pathname)
* [`UnixStream::connect`](http://doc.rust-lang.org/std/os/unix/net/struct.UnixStream.html#method.connect)
* [`UnixStream::pair`](http://doc.rust-lang.org/std/os/unix/net/struct.UnixStream.html#method.pair)
* [`UnixStream::try_clone`](http://doc.rust-lang.org/std/os/unix/net/struct.UnixStream.html#method.try_clone)
* [`UnixStream::local_addr`](http://doc.rust-lang.org/std/os/unix/net/struct.UnixStream.html#method.local_addr)
* [`UnixStream::peer_addr`](http://doc.rust-lang.org/std/os/unix/net/struct.UnixStream.html#method.peer_addr)
* [`UnixStream::set_read_timeout`](http://doc.rust-lang.org/std/os/unix/net/struct.UnixStream.html#method.read_timeout)
* [`UnixStream::set_write_timeout`](http://doc.rust-lang.org/std/os/unix/net/struct.UnixStream.html#method.write_timeout)
* [`UnixStream::read_timeout`](http://doc.rust-lang.org/std/os/unix/net/struct.UnixStream.html#method.read_timeout)
* [`UnixStream::write_timeout`](http://doc.rust-lang.org/std/os/unix/net/struct.UnixStream.html#method.write_timeout)
* [`UnixStream::set_nonblocking`](http://doc.rust-lang.org/std/os/unix/net/struct.UnixStream.html#method.set_nonblocking)
* [`UnixStream::take_error`](http://doc.rust-lang.org/std/os/unix/net/struct.UnixStream.html#method.take_error)
* [`UnixStream::shutdown`](http://doc.rust-lang.org/std/os/unix/net/struct.UnixStream.html#method.shutdown)
* Read/Write/RawFd impls for `UnixStream`
* [`UnixListener::bind`](http://doc.rust-lang.org/std/os/unix/net/struct.UnixListener.html#method.bind)
* [`UnixListener::accept`](http://doc.rust-lang.org/std/os/unix/net/struct.UnixListener.html#method.accept)
* [`UnixListener::try_clone`](http://doc.rust-lang.org/std/os/unix/net/struct.UnixListener.html#method.try_clone)
* [`UnixListener::local_addr`](http://doc.rust-lang.org/std/os/unix/net/struct.UnixListener.html#method.local_addr)
* [`UnixListener::set_nonblocking`](http://doc.rust-lang.org/std/os/unix/net/struct.UnixListener.html#method.set_nonblocking)
* [`UnixListener::take_error`](http://doc.rust-lang.org/std/os/unix/net/struct.UnixListener.html#method.take_error)
* [`UnixListener::incoming`](http://doc.rust-lang.org/std/os/unix/net/struct.UnixListener.html#method.incoming)
* RawFd impls for `UnixListener`
* [`UnixDatagram::bind`](http://doc.rust-lang.org/std/os/unix/net/struct.UnixDatagram.html#method.bind)
* [`UnixDatagram::unbound`](http://doc.rust-lang.org/std/os/unix/net/struct.UnixDatagram.html#method.unbound)
* [`UnixDatagram::pair`](http://doc.rust-lang.org/std/os/unix/net/struct.UnixDatagram.html#method.pair)
* [`UnixDatagram::connect`](http://doc.rust-lang.org/std/os/unix/net/struct.UnixDatagram.html#method.connect)
* [`UnixDatagram::try_clone`](http://doc.rust-lang.org/std/os/unix/net/struct.UnixDatagram.html#method.try_clone)
* [`UnixDatagram::local_addr`](http://doc.rust-lang.org/std/os/unix/net/struct.UnixDatagram.html#method.local_addr)
* [`UnixDatagram::peer_addr`](http://doc.rust-lang.org/std/os/unix/net/struct.UnixDatagram.html#method.peer_addr)
* [`UnixDatagram::recv_from`](http://doc.rust-lang.org/std/os/unix/net/struct.UnixDatagram.html#method.recv_from)
* [`UnixDatagram::recv`](http://doc.rust-lang.org/std/os/unix/net/struct.UnixDatagram.html#method.recv)
* [`UnixDatagram::send_to`](http://doc.rust-lang.org/std/os/unix/net/struct.UnixDatagram.html#method.send_to)
* [`UnixDatagram::send`](http://doc.rust-lang.org/std/os/unix/net/struct.UnixDatagram.html#method.send)
* [`UnixDatagram::set_read_timeout`](http://doc.rust-lang.org/std/os/unix/net/struct.UnixDatagram.html#method.set_read_timeout)
* [`UnixDatagram::set_write_timeout`](http://doc.rust-lang.org/std/os/unix/net/struct.UnixDatagram.html#method.set_write_timeout)
* [`UnixDatagram::read_timeout`](http://doc.rust-lang.org/std/os/unix/net/struct.UnixDatagram.html#method.read_timeout)
* [`UnixDatagram::write_timeout`](http://doc.rust-lang.org/std/os/unix/net/struct.UnixDatagram.html#method.write_timeout)
* [`UnixDatagram::set_nonblocking`](http://doc.rust-lang.org/std/os/unix/net/struct.UnixDatagram.html#method.set_nonblocking)
* [`UnixDatagram::take_error`](http://doc.rust-lang.org/std/os/unix/net/struct.UnixDatagram.html#method.take_error)
* [`UnixDatagram::shutdown`](http://doc.rust-lang.org/std/os/unix/net/struct.UnixDatagram.html#method.shutdown)
* RawFd impls for `UnixDatagram`
* `{BTree,Hash}Map::values_mut`
* [`<[_]>::binary_search_by_key`](http://doc.rust-lang.org/beta/std/primitive.slice.html#method.binary_search_by_key)
Libraries
---------
* [The `abs_sub` method of floats is deprecated](https://github.com/rust-lang/rust/pull/33664).
The semantics of this minor method are subtle and probably not what
most people want.
* [Add implementation of Ord for Cell<T> and RefCell<T> where T: Ord](https://github.com/rust-lang/rust/pull/33306).
* [On Linux, if `HashMap`s can't be initialized with `getrandom` they
will fall back to `/dev/urandom` temporarily to avoid blocking
during early boot](https://github.com/rust-lang/rust/pull/33086).
* [Implemented negation for wrapping numerals](https://github.com/rust-lang/rust/pull/33067).
* [Implement `Clone` for `binary_heap::IntoIter`](https://github.com/rust-lang/rust/pull/33050).
* [Implement `Display` and `Hash` for `std::num::Wrapping`](https://github.com/rust-lang/rust/pull/33023).
* [Add `Default` implementation for `&CStr`, `CString`](https://github.com/rust-lang/rust/pull/32990).
* [Implement `From<Vec<T>>` and `Into<Vec<T>>` for `VecDeque<T>`](https://github.com/rust-lang/rust/pull/32866).
* [Implement `Default` for `UnsafeCell`, `fmt::Error`, `Condvar`,
`Mutex`, `RwLock`](https://github.com/rust-lang/rust/pull/32785).
Cargo
-----
* [Cargo.toml supports the `profile.*.panic` option](https://github.com/rust-lang/cargo/pull/2687).
This controls the runtime behavior of the `panic!` macro
and can be either "unwind" (the default), or "abort".
[RFC 1513](https://github.com/rust-lang/rfcs/blob/master/text/1513-less-unwinding.md).
* [Don't throw away errors with `-p` arguments](https://github.com/rust-lang/cargo/pull/2723).
* [Report status to stderr instead of stdout](https://github.com/rust-lang/cargo/pull/2693).
* [Build scripts are passed a `CARGO_MANIFEST_LINKS` environment
variable that corresponds to the `links` field of the manifest](https://github.com/rust-lang/cargo/pull/2710).
* [Ban keywords from crate names](https://github.com/rust-lang/cargo/pull/2707).
* [Canonicalize `CARGO_HOME` on Windows](https://github.com/rust-lang/cargo/pull/2604).
* [Retry network requests](https://github.com/rust-lang/cargo/pull/2396).
By default they are retried twice, which can be customized with the
`net.retry` value in `.cargo/config`.
* [Don't print extra error info for failing subcommands](https://github.com/rust-lang/cargo/pull/2674).
* [Add `--force` flag to `cargo install`](https://github.com/rust-lang/cargo/pull/2405).
* [Don't use `flock` on NFS mounts](https://github.com/rust-lang/cargo/pull/2623).
* [Prefer building `cargo install` artifacts in temporary directories](https://github.com/rust-lang/cargo/pull/2610).
Makes it possible to install multiple crates in parallel.
* [Add `cargo test --doc`](https://github.com/rust-lang/cargo/pull/2578).
* [Add `cargo --explain`](https://github.com/rust-lang/cargo/pull/2551).
* [Don't print warnings when `-q` is passed](https://github.com/rust-lang/cargo/pull/2576).
* [Add `cargo doc --lib` and `--bin`](https://github.com/rust-lang/cargo/pull/2577).
* [Don't require build script output to be UTF-8](https://github.com/rust-lang/cargo/pull/2560).
* [Correctly attempt multiple git usernames](https://github.com/rust-lang/cargo/pull/2584).
Performance
-----------
* [rustc memory usage was reduced by refactoring the context used for
type checking](https://github.com/rust-lang/rust/pull/33425).
* [Speed up creation of `HashMap`s by caching the random keys used
to initialize the hash state](https://github.com/rust-lang/rust/pull/33318).
* [The `find` implementation for `Chain` iterators is 2x faster](https://github.com/rust-lang/rust/pull/33289).
* [Trait selection optimizations speed up type checking by 15%](https://github.com/rust-lang/rust/pull/33138).
* [Efficient trie lookup for boolean Unicode properties](https://github.com/rust-lang/rust/pull/33098).
10x faster than the previous lookup tables.
* [Special case `#[derive(Copy, Clone)]` to avoid bloat](https://github.com/rust-lang/rust/pull/31414).
Usability
---------
* Many incremental improvements to documentation and rustdoc.
* [rustdoc: List blanket trait impls](https://github.com/rust-lang/rust/pull/33514).
* [rustdoc: Clean up ABI rendering](https://github.com/rust-lang/rust/pull/33151).
* [Indexing with the wrong type produces a more informative error](https://github.com/rust-lang/rust/pull/33401).
* [Improve diagnostics for constants being used in irrefutable patterns](https://github.com/rust-lang/rust/pull/33406).
* [When many method candidates are in scope limit the suggestions to 10](https://github.com/rust-lang/rust/pull/33338).
* [Remove confusing suggestion when calling a `fn` type](https://github.com/rust-lang/rust/pull/33325).
* [Do not suggest changing `&mut self` to `&mut mut self`](https://github.com/rust-lang/rust/pull/33319).
Misc
----
* [Update i686-linux-android features to match Android ABI](https://github.com/rust-lang/rust/pull/33651).
* [Update aarch64-linux-android features to match Android ABI](https://github.com/rust-lang/rust/pull/33500).
* [`std` no longer prints backtraces on platforms where the running
module must be loaded with `env::current_exe`, which can't be relied
on](https://github.com/rust-lang/rust/pull/33554).
* This release includes std binaries for the i586-unknown-linux-gnu,
i686-unknown-linux-musl, and armv7-linux-androideabi targets. The
i586 target is for old x86 hardware without SSE2, and the armv7
target is for Android running on modern ARM architectures.
* [The `rust-gdb` and `rust-lldb` scripts are distributed on all
Unix platforms](https://github.com/rust-lang/rust/pull/32835).
* [On Unix the runtime aborts by calling `libc::abort` instead of
generating an illegal instruction](https://github.com/rust-lang/rust/pull/31457).
* [Rust is now bootstrapped from the previous release of Rust,
instead of a snapshot from an arbitrary commit](https://github.com/rust-lang/rust/pull/32942).
Compatibility Notes
-------------------
* [`AtomicBool` is now bool-sized, not word-sized](https://github.com/rust-lang/rust/pull/33579).
* [`target_env` for Linux ARM targets is just `gnu`, not
`gnueabihf`, `gnueabi`, etc](https://github.com/rust-lang/rust/pull/33403).
* [Consistently panic on overflow in `Duration::new`](https://github.com/rust-lang/rust/pull/33072).
* [Change `String::truncate` to panic less](https://github.com/rust-lang/rust/pull/32977).
* [Add `:block` to the follow set for `:ty` and `:path`](https://github.com/rust-lang/rust/pull/32945).
Affects how macros are parsed.
* [Fix macro hygiene bug](https://github.com/rust-lang/rust/pull/32923).
* [Feature-gated attributes on macro-generated macro invocations are
now rejected](https://github.com/rust-lang/rust/pull/32791).
* [Suppress fallback and ambiguity errors during type inference](https://github.com/rust-lang/rust/pull/32258).
This caused some minor changes to type inference.
Version 1.9.0 (2016-05-26)
==========================
Language
--------
* The `#[deprecated]` attribute when applied to an API will generate
warnings when used. The warnings may be suppressed with
`#[allow(deprecated)]`. [RFC 1270].
* [`fn` item types are zero sized, and each `fn` names a unique
type][1.9fn]. This will break code that transmutes `fn`s, so calling
`transmute` on a `fn` type will generate a warning for a few cycles,
then will be converted to an error.
* [Field and method resolution understand visibility, so private
fields and methods cannot prevent the proper use of public fields
and methods][1.9fv].
* [The parser considers unicode codepoints in the
`PATTERN_WHITE_SPACE` category to be whitespace][1.9ws].
Stabilized APIs
---------------
* [`std::panic`]
* [`std::panic::catch_unwind`][] (renamed from `recover`)
* [`std::panic::resume_unwind`][] (renamed from `propagate`)
* [`std::panic::AssertUnwindSafe`][] (renamed from `AssertRecoverSafe`)
* [`std::panic::UnwindSafe`][] (renamed from `RecoverSafe`)
* [`str::is_char_boundary`]
* [`<*const T>::as_ref`]
* [`<*mut T>::as_ref`]
* [`<*mut T>::as_mut`]
* [`AsciiExt::make_ascii_uppercase`]
* [`AsciiExt::make_ascii_lowercase`]
* [`char::decode_utf16`]
* [`char::DecodeUtf16`]
* [`char::DecodeUtf16Error`]
* [`char::DecodeUtf16Error::unpaired_surrogate`]
* [`BTreeSet::take`]
* [`BTreeSet::replace`]
* [`BTreeSet::get`]
* [`HashSet::take`]
* [`HashSet::replace`]
* [`HashSet::get`]
* [`OsString::with_capacity`]
* [`OsString::clear`]
* [`OsString::capacity`]
* [`OsString::reserve`]
* [`OsString::reserve_exact`]
* [`OsStr::is_empty`]
* [`OsStr::len`]
* [`std::os::unix::thread`]
* [`RawPthread`]
* [`JoinHandleExt`]
* [`JoinHandleExt::as_pthread_t`]
* [`JoinHandleExt::into_pthread_t`]
* [`HashSet::hasher`]
* [`HashMap::hasher`]
* [`CommandExt::exec`]
* [`File::try_clone`]
* [`SocketAddr::set_ip`]
* [`SocketAddr::set_port`]
* [`SocketAddrV4::set_ip`]
* [`SocketAddrV4::set_port`]
* [`SocketAddrV6::set_ip`]
* [`SocketAddrV6::set_port`]
* [`SocketAddrV6::set_flowinfo`]
* [`SocketAddrV6::set_scope_id`]
* [`slice::copy_from_slice`]
* [`ptr::read_volatile`]
* [`ptr::write_volatile`]
* [`OpenOptions::create_new`]
* [`TcpStream::set_nodelay`]
* [`TcpStream::nodelay`]
* [`TcpStream::set_ttl`]
* [`TcpStream::ttl`]
* [`TcpStream::set_only_v6`]
* [`TcpStream::only_v6`]
* [`TcpStream::take_error`]
* [`TcpStream::set_nonblocking`]
* [`TcpListener::set_ttl`]
* [`TcpListener::ttl`]
* [`TcpListener::set_only_v6`]
* [`TcpListener::only_v6`]
* [`TcpListener::take_error`]
* [`TcpListener::set_nonblocking`]
* [`UdpSocket::set_broadcast`]
* [`UdpSocket::broadcast`]
* [`UdpSocket::set_multicast_loop_v4`]
* [`UdpSocket::multicast_loop_v4`]
* [`UdpSocket::set_multicast_ttl_v4`]
* [`UdpSocket::multicast_ttl_v4`]
* [`UdpSocket::set_multicast_loop_v6`]
* [`UdpSocket::multicast_loop_v6`]
* [`UdpSocket::set_multicast_ttl_v6`]
* [`UdpSocket::multicast_ttl_v6`]
* [`UdpSocket::set_ttl`]
* [`UdpSocket::ttl`]
* [`UdpSocket::set_only_v6`]
* [`UdpSocket::only_v6`]
* [`UdpSocket::join_multicast_v4`]
* [`UdpSocket::join_multicast_v6`]
* [`UdpSocket::leave_multicast_v4`]
* [`UdpSocket::leave_multicast_v6`]
* [`UdpSocket::take_error`]
* [`UdpSocket::connect`]
* [`UdpSocket::send`]
* [`UdpSocket::recv`]
* [`UdpSocket::set_nonblocking`]
Libraries
---------
* [`std::sync::Once` is poisoned if its initialization function
fails][1.9o].
* [`cell::Ref` and `cell::RefMut` can contain unsized types][1.9cu].
* [Most types implement `fmt::Debug`][1.9db].
* [The default buffer size used by `BufReader` and `BufWriter` was
reduced to 8K, from 64K][1.9bf]. This is in line with the buffer size
used by other languages.
* [`Instant`, `SystemTime` and `Duration` implement `+=` and `-=`.
`Duration` additionally implements `*=` and `/=`][1.9ta].
* [`Skip` is a `DoubleEndedIterator`][1.9sk].
* [`From<[u8; 4]>` is implemented for `Ipv4Addr`][1.9fi].
* [`Chain` implements `BufRead`][1.9ch].
* [`HashMap`, `HashSet` and iterators are covariant][1.9hc].
Cargo
-----
* [Cargo can now run concurrently][1.9cc].
* [Top-level overrides allow specific revisions of crates to be
overridden through the entire crate graph][1.9ct]. This is intended
to make upgrades easier for large projects, by allowing crates to be
forked temporarily until they've been upgraded and republished.
* [Cargo exports a `CARGO_PKG_AUTHORS` environment variable][1.9cp].
* [Cargo will pass the contents of the `RUSTFLAGS` variable to `rustc`
on the commandline][1.9cf]. `rustc` arguments can also be specified
in the `build.rustflags` configuration key.
Performance
-----------
* [The time complexity of comparing variables for equivalence during type
unification is reduced from _O_(_n_!) to _O_(_n_)][1.9tu]. This leads
to major compilation time improvement in some scenarios.
* [`ToString` is specialized for `str`, giving it the same performance
as `to_owned`][1.9ts].
* [Spawning processes with `Command::output` no longer creates extra
threads][1.9sp].
* [`#[derive(PartialEq)]` and `#[derive(PartialOrd)]` emit less code
for C-like enums][1.9cl].
Misc
----
* [Passing the `--quiet` flag to a test runner will produce
much-abbreviated output][1.9q].
* The Rust Project now publishes std binaries for the
`mips-unknown-linux-musl`, `mipsel-unknown-linux-musl`, and
`i586-pc-windows-msvc` targets.
Compatibility Notes
-------------------
* [`std::sync::Once` is poisoned if its initialization function
fails][1.9o].
* [It is illegal to define methods with the same name in overlapping
inherent `impl` blocks][1.9sn].
* [`fn` item types are zero sized, and each `fn` names a unique
type][1.9fn]. This will break code that transmutes `fn`s, so calling
`transmute` on a `fn` type will generate a warning for a few cycles,
then will be converted to an error.
* [Improvements to const evaluation may trigger new errors when integer
literals are out of range][1.9ce].
[1.9bf]: https://github.com/rust-lang/rust/pull/32695
[1.9cc]: https://github.com/rust-lang/cargo/pull/2486
[1.9ce]: https://github.com/rust-lang/rust/pull/30587
[1.9cf]: https://github.com/rust-lang/cargo/pull/2241
[1.9ch]: https://github.com/rust-lang/rust/pull/32541
[1.9cl]: https://github.com/rust-lang/rust/pull/31977
[1.9cp]: https://github.com/rust-lang/cargo/pull/2465
[1.9ct]: https://github.com/rust-lang/cargo/pull/2385
[1.9cu]: https://github.com/rust-lang/rust/pull/32652
[1.9db]: https://github.com/rust-lang/rust/pull/32054
[1.9fi]: https://github.com/rust-lang/rust/pull/32050
[1.9fn]: https://github.com/rust-lang/rust/pull/31710
[1.9fv]: https://github.com/rust-lang/rust/pull/31938
[1.9hc]: https://github.com/rust-lang/rust/pull/32635
[1.9o]: https://github.com/rust-lang/rust/pull/32325
[1.9q]: https://github.com/rust-lang/rust/pull/31887
[1.9sk]: https://github.com/rust-lang/rust/pull/31700
[1.9sn]: https://github.com/rust-lang/rust/pull/31925
[1.9sp]: https://github.com/rust-lang/rust/pull/31618
[1.9ta]: https://github.com/rust-lang/rust/pull/32448
[1.9ts]: https://github.com/rust-lang/rust/pull/32586
[1.9tu]: https://github.com/rust-lang/rust/pull/32062
[1.9ws]: https://github.com/rust-lang/rust/pull/29734
[RFC 1270]: https://github.com/rust-lang/rfcs/blob/master/text/1270-deprecation.md
[`<*const T>::as_ref`]: http://doc.rust-lang.org/nightly/std/primitive.pointer.html#method.as_ref
[`<*mut T>::as_mut`]: http://doc.rust-lang.org/nightly/std/primitive.pointer.html#method.as_mut
[`<*mut T>::as_ref`]: http://doc.rust-lang.org/nightly/std/primitive.pointer.html#method.as_ref
[`slice::copy_from_slice`]: http://doc.rust-lang.org/nightly/std/primitive.slice.html#method.copy_from_slice
[`AsciiExt::make_ascii_lowercase`]: http://doc.rust-lang.org/nightly/std/ascii/trait.AsciiExt.html#tymethod.make_ascii_lowercase
[`AsciiExt::make_ascii_uppercase`]: http://doc.rust-lang.org/nightly/std/ascii/trait.AsciiExt.html#tymethod.make_ascii_uppercase
[`BTreeSet::get`]: http://doc.rust-lang.org/nightly/collections/btree/set/struct.BTreeSet.html#method.get
[`BTreeSet::replace`]: http://doc.rust-lang.org/nightly/collections/btree/set/struct.BTreeSet.html#method.replace
[`BTreeSet::take`]: http://doc.rust-lang.org/nightly/collections/btree/set/struct.BTreeSet.html#method.take
[`CommandExt::exec`]: http://doc.rust-lang.org/nightly/std/os/unix/process/trait.CommandExt.html#tymethod.exec
[`File::try_clone`]: http://doc.rust-lang.org/nightly/std/fs/struct.File.html#method.try_clone
[`HashMap::hasher`]: http://doc.rust-lang.org/nightly/std/collections/struct.HashMap.html#method.hasher
[`HashSet::get`]: http://doc.rust-lang.org/nightly/std/collections/struct.HashSet.html#method.get
[`HashSet::hasher`]: http://doc.rust-lang.org/nightly/std/collections/struct.HashSet.html#method.hasher
[`HashSet::replace`]: http://doc.rust-lang.org/nightly/std/collections/struct.HashSet.html#method.replace
[`HashSet::take`]: http://doc.rust-lang.org/nightly/std/collections/struct.HashSet.html#method.take
[`JoinHandleExt::as_pthread_t`]: http://doc.rust-lang.org/nightly/std/os/unix/thread/trait.JoinHandleExt.html#tymethod.as_pthread_t
[`JoinHandleExt::into_pthread_t`]: http://doc.rust-lang.org/nightly/std/os/unix/thread/trait.JoinHandleExt.html#tymethod.into_pthread_t
[`JoinHandleExt`]: http://doc.rust-lang.org/nightly/std/os/unix/thread/trait.JoinHandleExt.html
[`OpenOptions::create_new`]: http://doc.rust-lang.org/nightly/std/fs/struct.OpenOptions.html#method.create_new
[`OsStr::is_empty`]: http://doc.rust-lang.org/nightly/std/ffi/struct.OsStr.html#method.is_empty
[`OsStr::len`]: http://doc.rust-lang.org/nightly/std/ffi/struct.OsStr.html#method.len
[`OsString::capacity`]: http://doc.rust-lang.org/nightly/std/ffi/struct.OsString.html#method.capacity
[`OsString::clear`]: http://doc.rust-lang.org/nightly/std/ffi/struct.OsString.html#method.clear
[`OsString::reserve_exact`]: http://doc.rust-lang.org/nightly/std/ffi/struct.OsString.html#method.reserve_exact
[`OsString::reserve`]: http://doc.rust-lang.org/nightly/std/ffi/struct.OsString.html#method.reserve
[`OsString::with_capacity`]: http://doc.rust-lang.org/nightly/std/ffi/struct.OsString.html#method.with_capacity
[`RawPthread`]: http://doc.rust-lang.org/nightly/std/os/unix/thread/type.RawPthread.html
[`SocketAddr::set_ip`]: http://doc.rust-lang.org/nightly/std/net/enum.SocketAddr.html#method.set_ip
[`SocketAddr::set_port`]: http://doc.rust-lang.org/nightly/std/net/enum.SocketAddr.html#method.set_port
[`SocketAddrV4::set_ip`]: http://doc.rust-lang.org/nightly/std/net/struct.SocketAddrV4.html#method.set_ip
[`SocketAddrV4::set_port`]: http://doc.rust-lang.org/nightly/std/net/struct.SocketAddrV4.html#method.set_port
[`SocketAddrV6::set_flowinfo`]: http://doc.rust-lang.org/nightly/std/net/struct.SocketAddrV6.html#method.set_flowinfo
[`SocketAddrV6::set_ip`]: http://doc.rust-lang.org/nightly/std/net/struct.SocketAddrV6.html#method.set_ip
[`SocketAddrV6::set_port`]: http://doc.rust-lang.org/nightly/std/net/struct.SocketAddrV6.html#method.set_port
[`SocketAddrV6::set_scope_id`]: http://doc.rust-lang.org/nightly/std/net/struct.SocketAddrV6.html#method.set_scope_id
[`TcpListener::only_v6`]: http://doc.rust-lang.org/nightly/std/net/struct.TcpStream.html#method.only_v6
[`TcpListener::set_nonblocking`]: http://doc.rust-lang.org/nightly/std/net/struct.TcpStream.html#method.set_nonblocking
[`TcpListener::set_only_v6`]: http://doc.rust-lang.org/nightly/std/net/struct.TcpStream.html#method.set_only_v6
[`TcpListener::set_ttl`]: http://doc.rust-lang.org/nightly/std/net/struct.TcpStream.html#method.set_ttl
[`TcpListener::take_error`]: http://doc.rust-lang.org/nightly/std/net/struct.TcpStream.html#method.take_error
[`TcpListener::ttl`]: http://doc.rust-lang.org/nightly/std/net/struct.TcpStream.html#method.ttl
[`TcpStream::nodelay`]: http://doc.rust-lang.org/nightly/std/net/struct.TcpStream.html#method.nodelay
[`TcpStream::only_v6`]: http://doc.rust-lang.org/nightly/std/net/struct.TcpStream.html#method.only_v6
[`TcpStream::set_nodelay`]: http://doc.rust-lang.org/nightly/std/net/struct.TcpStream.html#method.set_nodelay
[`TcpStream::set_nonblocking`]: http://doc.rust-lang.org/nightly/std/net/struct.TcpStream.html#method.set_nonblocking
[`TcpStream::set_only_v6`]: http://doc.rust-lang.org/nightly/std/net/struct.TcpStream.html#method.set_only_v6
[`TcpStream::set_ttl`]: http://doc.rust-lang.org/nightly/std/net/struct.TcpStream.html#method.set_ttl
[`TcpStream::take_error`]: http://doc.rust-lang.org/nightly/std/net/struct.TcpStream.html#method.take_error
[`TcpStream::ttl`]: http://doc.rust-lang.org/nightly/std/net/struct.TcpStream.html#method.ttl
[`UdpSocket::broadcast`]: http://doc.rust-lang.org/nightly/std/net/struct.UdpSocket.html#method.broadcast
[`UdpSocket::connect`]: http://doc.rust-lang.org/nightly/std/net/struct.UdpSocket.html#method.connect
[`UdpSocket::join_multicast_v4`]: http://doc.rust-lang.org/nightly/std/net/struct.UdpSocket.html#method.join_multicast_v4
[`UdpSocket::join_multicast_v6`]: http://doc.rust-lang.org/nightly/std/net/struct.UdpSocket.html#method.join_multicast_v6
[`UdpSocket::leave_multicast_v4`]: http://doc.rust-lang.org/nightly/std/net/struct.UdpSocket.html#method.leave_multicast_v4
[`UdpSocket::leave_multicast_v6`]: http://doc.rust-lang.org/nightly/std/net/struct.UdpSocket.html#method.leave_multicast_v6
[`UdpSocket::multicast_loop_v4`]: http://doc.rust-lang.org/nightly/std/net/struct.UdpSocket.html#method.multicast_loop_v4
[`UdpSocket::multicast_loop_v6`]: http://doc.rust-lang.org/nightly/std/net/struct.UdpSocket.html#method.multicast_loop_v6
[`UdpSocket::multicast_ttl_v4`]: http://doc.rust-lang.org/nightly/std/net/struct.UdpSocket.html#method.multicast_ttl_v4
[`UdpSocket::multicast_ttl_v6`]: http://doc.rust-lang.org/nightly/std/net/struct.UdpSocket.html#method.multicast_ttl_v6
[`UdpSocket::only_v6`]: http://doc.rust-lang.org/nightly/std/net/struct.UdpSocket.html#method.only_v6
[`UdpSocket::recv`]: http://doc.rust-lang.org/nightly/std/net/struct.UdpSocket.html#method.recv
[`UdpSocket::send`]: http://doc.rust-lang.org/nightly/std/net/struct.UdpSocket.html#method.send
[`UdpSocket::set_broadcast`]: http://doc.rust-lang.org/nightly/std/net/struct.UdpSocket.html#method.set_broadcast
[`UdpSocket::set_multicast_loop_v4`]: http://doc.rust-lang.org/nightly/std/net/struct.UdpSocket.html#method.set_multicast_loop_v4
[`UdpSocket::set_multicast_loop_v6`]: http://doc.rust-lang.org/nightly/std/net/struct.UdpSocket.html#method.set_multicast_loop_v6
[`UdpSocket::set_multicast_ttl_v4`]: http://doc.rust-lang.org/nightly/std/net/struct.UdpSocket.html#method.set_multicast_ttl_v4
[`UdpSocket::set_multicast_ttl_v6`]: http://doc.rust-lang.org/nightly/std/net/struct.UdpSocket.html#method.set_multicast_ttl_v6
[`UdpSocket::set_nonblocking`]: http://doc.rust-lang.org/nightly/std/net/struct.UdpSocket.html#method.set_nonblocking
[`UdpSocket::set_only_v6`]: http://doc.rust-lang.org/nightly/std/net/struct.UdpSocket.html#method.set_only_v6
[`UdpSocket::set_ttl`]: http://doc.rust-lang.org/nightly/std/net/struct.UdpSocket.html#method.set_ttl
[`UdpSocket::take_error`]: http://doc.rust-lang.org/nightly/std/net/struct.UdpSocket.html#method.take_error
[`UdpSocket::ttl`]: http://doc.rust-lang.org/nightly/std/net/struct.UdpSocket.html#method.ttl
[`char::DecodeUtf16Error::unpaired_surrogate`]: http://doc.rust-lang.org/nightly/std/char/struct.DecodeUtf16Error.html#method.unpaired_surrogate
[`char::DecodeUtf16Error`]: http://doc.rust-lang.org/nightly/std/char/struct.DecodeUtf16Error.html
[`char::DecodeUtf16`]: http://doc.rust-lang.org/nightly/std/char/struct.DecodeUtf16.html
[`char::decode_utf16`]: http://doc.rust-lang.org/nightly/std/char/fn.decode_utf16.html
[`ptr::read_volatile`]: http://doc.rust-lang.org/nightly/std/ptr/fn.read_volatile.html
[`ptr::write_volatile`]: http://doc.rust-lang.org/nightly/std/ptr/fn.write_volatile.html
[`std::os::unix::thread`]: http://doc.rust-lang.org/nightly/std/os/unix/thread/index.html
[`std::panic::AssertUnwindSafe`]: http://doc.rust-lang.org/nightly/std/panic/struct.AssertUnwindSafe.html
[`std::panic::UnwindSafe`]: http://doc.rust-lang.org/nightly/std/panic/trait.UnwindSafe.html
[`std::panic::catch_unwind`]: http://doc.rust-lang.org/nightly/std/panic/fn.catch_unwind.html
[`std::panic::resume_unwind`]: http://doc.rust-lang.org/nightly/std/panic/fn.resume_unwind.html
[`std::panic`]: http://doc.rust-lang.org/nightly/std/panic/index.html
[`str::is_char_boundary`]: http://doc.rust-lang.org/nightly/std/primitive.str.html#method.is_char_boundary
Version 1.8.0 (2016-04-14)
==========================
Language
--------
* Rust supports overloading of compound assignment statements like
`+=` by implementing the [`AddAssign`], [`SubAssign`],
[`MulAssign`], [`DivAssign`], [`RemAssign`], [`BitAndAssign`],
[`BitOrAssign`], [`BitXorAssign`], [`ShlAssign`], or [`ShrAssign`]
traits. [RFC 953].
* Empty structs can be defined with braces, as in `struct Foo { }`, in
addition to the non-braced form, `struct Foo;`. [RFC 218].
Libraries
---------
* Stabilized APIs:
* [`str::encode_utf16`][] (renamed from `utf16_units`)
* [`str::EncodeUtf16`][] (renamed from `Utf16Units`)
* [`Ref::map`]
* [`RefMut::map`]
* [`ptr::drop_in_place`]
* [`time::Instant`]
* [`time::SystemTime`]
* [`Instant::now`]
* [`Instant::duration_since`][] (renamed from `duration_from_earlier`)
* [`Instant::elapsed`]
* [`SystemTime::now`]
* [`SystemTime::duration_since`][] (renamed from `duration_from_earlier`)
* [`SystemTime::elapsed`]
* Various `Add`/`Sub` impls for `Time` and `SystemTime`
* [`SystemTimeError`]
* [`SystemTimeError::duration`]
* Various impls for `SystemTimeError`
* [`UNIX_EPOCH`]
* [`AddAssign`], [`SubAssign`], [`MulAssign`], [`DivAssign`],
[`RemAssign`], [`BitAndAssign`], [`BitOrAssign`],
[`BitXorAssign`], [`ShlAssign`], [`ShrAssign`].
* [The `write!` and `writeln!` macros correctly emit errors if any of
their arguments can't be formatted][1.8w].
* [Various I/O functions support large files on 32-bit Linux][1.8l].
* [The Unix-specific `raw` modules, which contain a number of
redefined C types are deprecated][1.8r], including `os::raw::unix`,
`os::raw::macos`, and `os::raw::linux`. These modules defined types
such as `ino_t` and `dev_t`. The inconsistency of these definitions
across platforms was making it difficult to implement `std`
correctly. Those that need these definitions should use the `libc`
crate. [RFC 1415].
* The Unix-specific `MetadataExt` traits, including
`os::unix::fs::MetadataExt`, which expose values such as inode
numbers [no longer return platform-specific types][1.8r], but
instead return widened integers. [RFC 1415].
* [`btree_set::{IntoIter, Iter, Range}` are covariant][1.8cv].
* [Atomic loads and stores are not volatile][1.8a].
* [All types in `sync::mpsc` implement `fmt::Debug`][1.8mp].
Performance
-----------
* [Inlining hash functions lead to a 3% compile-time improvement in
some workloads][1.8h].
* When using jemalloc, its symbols are [unprefixed so that it
overrides the libc malloc implementation][1.8h]. This means that for
rustc, LLVM is now using jemalloc, which results in a 6%
compile-time improvement on a specific workload.
* [Avoid quadratic growth in function size due to cleanups][1.8cu].
Misc
----
* [32-bit MSVC builds finally implement unwinding][1.8ms].
i686-pc-windows-msvc is now considered a tier-1 platform.
* [The `--print targets` flag prints a list of supported targets][1.8t].
* [The `--print cfg` flag prints the `cfg`s defined for the current
target][1.8cf].
* [`rustc` can be built with an new Cargo-based build system, written
in Rust][1.8b]. It will eventually replace Rust's Makefile-based
build system. To enable it configure with `configure --rustbuild`.
* [Errors for non-exhaustive `match` patterns now list up to 3 missing
variants while also indicating the total number of missing variants
if more than 3][1.8m].
* [Executable stacks are disabled on Linux and BSD][1.8nx].
* The Rust Project now publishes binary releases of the standard
library for a number of tier-2 targets:
`armv7-unknown-linux-gnueabihf`, `powerpc-unknown-linux-gnu`,
`powerpc64-unknown-linux-gnu`, `powerpc64le-unknown-linux-gnu`
`x86_64-rumprun-netbsd`. These can be installed with
tools such as [multirust][1.8mr].
Cargo
-----
* [`cargo init` creates a new Cargo project in the current
directory][1.8ci]. It is otherwise like `cargo new`.
* [Cargo has configuration keys for `-v` and
`--color`][1.8cc]. `verbose` and `color`, respectively, go in the
`[term]` section of `.cargo/config`.
* [Configuration keys that evaluate to strings or integers can be set
via environment variables][1.8ce]. For example the `build.jobs` key
can be set via `CARGO_BUILD_JOBS`. Environment variables take
precedence over config files.
* [Target-specific dependencies support Rust `cfg` syntax for
describing targets][1.8cfg] so that dependencies for multiple
targets can be specified together. [RFC 1361].
* [The environment variables `CARGO_TARGET_ROOT`, `RUSTC`, and
`RUSTDOC` take precedence over the `build.target-dir`,
`build.rustc`, and `build.rustdoc` configuration values][1.8cv].
* [The child process tree is killed on Windows when Cargo is
killed][1.8ck].
* [The `build.target` configuration value sets the target platform,
like `--target`][1.8ct].
Compatibility Notes
-------------------
* [Unstable compiler flags have been further restricted][1.8u]. Since
1.0 `-Z` flags have been considered unstable, and other flags that
were considered unstable additionally required passing `-Z
unstable-options` to access. Unlike unstable language and library
features though, these options have been accessible on the stable
release channel. Going forward, *new unstable flags will not be
available on the stable release channel*, and old unstable flags
will warn about their usage. In the future, all unstable flags will
be unavailable on the stable release channel.
* [It is no longer possible to `match` on empty enum variants using
the `Variant(..)` syntax][1.8v]. This has been a warning since 1.6.
* The Unix-specific `MetadataExt` traits, including
`os::unix::fs::MetadataExt`, which expose values such as inode
numbers [no longer return platform-specific types][1.8r], but
instead return widened integers. [RFC 1415].
* [Modules sourced from the filesystem cannot appear within arbitrary
blocks, but only within other modules][1.8mf].
* [`--cfg` compiler flags are parsed strictly as identifiers][1.8c].
* On Unix, [stack overflow triggers a runtime abort instead of a
SIGSEGV][1.8so].
* [`Command::spawn` and its equivalents return an error if any of
its command-line arguments contain interior `NUL`s][1.8n].
* [Tuple and unit enum variants from other crates are in the type
namespace][1.8tn].
* [On Windows `rustc` emits `.lib` files for the `staticlib` library
type instead of `.a` files][1.8st]. Additionally, for the MSVC
toolchain, `rustc` emits import libraries named `foo.dll.lib`
instead of `foo.lib`.
[1.8a]: https://github.com/rust-lang/rust/pull/30962
[1.8b]: https://github.com/rust-lang/rust/pull/31123
[1.8c]: https://github.com/rust-lang/rust/pull/31530
[1.8cc]: https://github.com/rust-lang/cargo/pull/2397
[1.8ce]: https://github.com/rust-lang/cargo/pull/2398
[1.8cf]: https://github.com/rust-lang/rust/pull/31278
[1.8cfg]: https://github.com/rust-lang/cargo/pull/2328
[1.8ci]: https://github.com/rust-lang/cargo/pull/2081
[1.8ck]: https://github.com/rust-lang/cargo/pull/2370
[1.8ct]: https://github.com/rust-lang/cargo/pull/2335
[1.8cu]: https://github.com/rust-lang/rust/pull/31390
[1.8cv]: https://github.com/rust-lang/cargo/issues/2365
[1.8cv]: https://github.com/rust-lang/rust/pull/30998
[1.8h]: https://github.com/rust-lang/rust/pull/31460
[1.8l]: https://github.com/rust-lang/rust/pull/31668
[1.8m]: https://github.com/rust-lang/rust/pull/31020
[1.8mf]: https://github.com/rust-lang/rust/pull/31534
[1.8mp]: https://github.com/rust-lang/rust/pull/30894
[1.8mr]: https://users.rust-lang.org/t/multirust-0-8-with-cross-std-installation/4901
[1.8ms]: https://github.com/rust-lang/rust/pull/30448
[1.8n]: https://github.com/rust-lang/rust/pull/31056
[1.8nx]: https://github.com/rust-lang/rust/pull/30859
[1.8r]: https://github.com/rust-lang/rust/pull/31551
[1.8so]: https://github.com/rust-lang/rust/pull/31333
[1.8st]: https://github.com/rust-lang/rust/pull/29520
[1.8t]: https://github.com/rust-lang/rust/pull/31358
[1.8tn]: https://github.com/rust-lang/rust/pull/30882
[1.8u]: https://github.com/rust-lang/rust/pull/31793
[1.8v]: https://github.com/rust-lang/rust/pull/31757
[1.8w]: https://github.com/rust-lang/rust/pull/31904
[RFC 1361]: https://github.com/rust-lang/rfcs/blob/master/text/1361-cargo-cfg-dependencies.md
[RFC 1415]: https://github.com/rust-lang/rfcs/blob/master/text/1415-trim-std-os.md
[RFC 218]: https://github.com/rust-lang/rfcs/blob/master/text/0218-empty-struct-with-braces.md
[RFC 953]: https://github.com/rust-lang/rfcs/blob/master/text/0953-op-assign.md
[`AddAssign`]: http://doc.rust-lang.org/nightly/std/ops/trait.AddAssign.html
[`BitAndAssign`]: http://doc.rust-lang.org/nightly/std/ops/trait.BitAndAssign.html
[`BitOrAssign`]: http://doc.rust-lang.org/nightly/std/ops/trait.BitOrAssign.html
[`BitXorAssign`]: http://doc.rust-lang.org/nightly/std/ops/trait.BitXorAssign.html
[`DivAssign`]: http://doc.rust-lang.org/nightly/std/ops/trait.DivAssign.html
[`Instant::duration_since`]: http://doc.rust-lang.org/nightly/std/time/struct.Instant.html#method.duration_since
[`Instant::elapsed`]: http://doc.rust-lang.org/nightly/std/time/struct.Instant.html#method.elapsed
[`Instant::now`]: http://doc.rust-lang.org/nightly/std/time/struct.Instant.html#method.now
[`MulAssign`]: http://doc.rust-lang.org/nightly/std/ops/trait.MulAssign.html
[`Ref::map`]: http://doc.rust-lang.org/nightly/std/cell/struct.Ref.html#method.map
[`RefMut::map`]: http://doc.rust-lang.org/nightly/std/cell/struct.RefMut.html#method.map
[`RemAssign`]: http://doc.rust-lang.org/nightly/std/ops/trait.RemAssign.html
[`ShlAssign`]: http://doc.rust-lang.org/nightly/std/ops/trait.ShlAssign.html
[`ShrAssign`]: http://doc.rust-lang.org/nightly/std/ops/trait.ShrAssign.html
[`SubAssign`]: http://doc.rust-lang.org/nightly/std/ops/trait.SubAssign.html
[`SystemTime::duration_since`]: http://doc.rust-lang.org/nightly/std/time/struct.SystemTime.html#method.duration_since
[`SystemTime::elapsed`]: http://doc.rust-lang.org/nightly/std/time/struct.SystemTime.html#method.elapsed
[`SystemTime::now`]: http://doc.rust-lang.org/nightly/std/time/struct.SystemTime.html#method.now
[`SystemTimeError::duration`]: http://doc.rust-lang.org/nightly/std/time/struct.SystemTimeError.html#method.duration
[`SystemTimeError`]: http://doc.rust-lang.org/nightly/std/time/struct.SystemTimeError.html
[`UNIX_EPOCH`]: http://doc.rust-lang.org/nightly/std/time/constant.UNIX_EPOCH.html
[`ptr::drop_in_place`]: http://doc.rust-lang.org/nightly/std/ptr/fn.drop_in_place.html
[`str::EncodeUtf16`]: http://doc.rust-lang.org/nightly/std/str/struct.EncodeUtf16.html
[`str::encode_utf16`]: http://doc.rust-lang.org/nightly/std/primitive.str.html#method.encode_utf16
[`time::Instant`]: http://doc.rust-lang.org/nightly/std/time/struct.Instant.html
[`time::SystemTime`]: http://doc.rust-lang.org/nightly/std/time/struct.SystemTime.html
Version 1.7.0 (2016-03-03)
==========================
Libraries
---------
* Stabilized APIs
* `Path`
* [`Path::strip_prefix`][] (renamed from relative_from)
* [`path::StripPrefixError`][] (new error type returned from strip_prefix)
* `Ipv4Addr`
* [`Ipv4Addr::is_loopback`]
* [`Ipv4Addr::is_private`]
* [`Ipv4Addr::is_link_local`]
* [`Ipv4Addr::is_multicast`]
* [`Ipv4Addr::is_broadcast`]
* [`Ipv4Addr::is_documentation`]
* `Ipv6Addr`
* [`Ipv6Addr::is_unspecified`]
* [`Ipv6Addr::is_loopback`]
* [`Ipv6Addr::is_multicast`]
* `Vec`
* [`Vec::as_slice`]
* [`Vec::as_mut_slice`]
* `String`
* [`String::as_str`]
* [`String::as_mut_str`]
* Slices
* `<[T]>::`[`clone_from_slice`], which now requires the two slices to
be the same length
* `<[T]>::`[`sort_by_key`]
* checked, saturated, and overflowing operations
* [`i32::checked_rem`], [`i32::checked_neg`], [`i32::checked_shl`], [`i32::checked_shr`]
* [`i32::saturating_mul`]
* [`i32::overflowing_add`], [`i32::overflowing_sub`], [`i32::overflowing_mul`], [`i32::overflowing_div`]
* [`i32::overflowing_rem`], [`i32::overflowing_neg`], [`i32::overflowing_shl`], [`i32::overflowing_shr`]
* [`u32::checked_rem`], [`u32::checked_neg`], [`u32::checked_shl`], [`u32::checked_shl`]
* [`u32::saturating_mul`]
* [`u32::overflowing_add`], [`u32::overflowing_sub`], [`u32::overflowing_mul`], [`u32::overflowing_div`]
* [`u32::overflowing_rem`], [`u32::overflowing_neg`], [`u32::overflowing_shl`], [`u32::overflowing_shr`]
* and checked, saturated, and overflowing operations for other primitive types
* FFI
* [`ffi::IntoStringError`]
* [`CString::into_string`]
* [`CString::into_bytes`]
* [`CString::into_bytes_with_nul`]
* `From<CString> for Vec<u8>`
* `IntoStringError`
* [`IntoStringError::into_cstring`]
* [`IntoStringError::utf8_error`]
* `Error for IntoStringError`
* Hashing
* [`std::hash::BuildHasher`]
* [`BuildHasher::Hasher`]
* [`BuildHasher::build_hasher`]
* [`std::hash::BuildHasherDefault`]
* [`HashMap::with_hasher`]
* [`HashMap::with_capacity_and_hasher`]
* [`HashSet::with_hasher`]
* [`HashSet::with_capacity_and_hasher`]
* [`std::collections::hash_map::RandomState`]
* [`RandomState::new`]
* [Validating UTF-8 is faster by a factor of between 7 and 14x for
ASCII input][1.7utf8]. This means that creating `String`s and `str`s
from bytes is faster.
* [The performance of `LineWriter` (and thus `io::stdout`) was
improved by using `memchr` to search for newlines][1.7m].
* [`f32::to_degrees` and `f32::to_radians` are stable][1.7f]. The
`f64` variants were stabilized previously.
* [`BTreeMap` was rewritten to use less memory and improve the performance
of insertion and iteration, the latter by as much as 5x][1.7bm].
* [`BTreeSet` and its iterators, `Iter`, `IntoIter`, and `Range` are
covariant over their contained type][1.7bt].
* [`LinkedList` and its iterators, `Iter` and `IntoIter` are covariant
over their contained type][1.7ll].
* [`str::replace` now accepts a `Pattern`][1.7rp], like other string
searching methods.
* [`Any` is implemented for unsized types][1.7a].
* [`Hash` is implemented for `Duration`][1.7h].
Misc
----
* [When running tests with `--test`, rustdoc will pass `--cfg`
arguments to the compiler][1.7dt].
* [The compiler is built with RPATH information by default][1.7rpa].
This means that it will be possible to run `rustc` when installed in
unusual configurations without configuring the dynamic linker search
path explicitly.
* [`rustc` passes `--enable-new-dtags` to GNU ld][1.7dta]. This makes
any RPATH entries (emitted with `-C rpath`) *not* take precedence
over `LD_LIBRARY_PATH`.
Cargo
-----
* [`cargo rustc` accepts a `--profile` flag that runs `rustc` under
any of the compilation profiles, 'dev', 'bench', or 'test'][1.7cp].
* [The `rerun-if-changed` build script directive no longer causes the
build script to incorrectly run twice in certain scenarios][1.7rr].
Compatibility Notes
-------------------
* Soundness fixes to the interactions between associated types and
lifetimes, specified in [RFC 1214], [now generate errors][1.7sf] for
code that violates the new rules. This is a significant change that
is known to break existing code, so it has emitted warnings for the
new error cases since 1.4 to give crate authors time to adapt. The
details of what is changing are subtle; read the RFC for more.
* [Several bugs in the compiler's visibility calculations were
fixed][1.7v]. Since this was found to break significant amounts of
code, the new errors will be emitted as warnings for several release
cycles, under the `private_in_public` lint.
* Defaulted type parameters were accidentally accepted in positions
that were not intended. In this release, [defaulted type parameters
appearing outside of type definitions will generate a
warning][1.7d], which will become an error in future releases.
* [Parsing "." as a float results in an error instead of 0][1.7p].
That is, `".".parse::<f32>()` returns `Err`, not `Ok(0.0)`.
* [Borrows of closure parameters may not outlive the closure][1.7bc].
[1.7a]: https://github.com/rust-lang/rust/pull/30928
[1.7bc]: https://github.com/rust-lang/rust/pull/30341
[1.7bm]: https://github.com/rust-lang/rust/pull/30426
[1.7bt]: https://github.com/rust-lang/rust/pull/30998
[1.7cp]: https://github.com/rust-lang/cargo/pull/2224
[1.7d]: https://github.com/rust-lang/rust/pull/30724
[1.7dt]: https://github.com/rust-lang/rust/pull/30372
[1.7dta]: https://github.com/rust-lang/rust/pull/30394
[1.7f]: https://github.com/rust-lang/rust/pull/30672
[1.7h]: https://github.com/rust-lang/rust/pull/30818
[1.7ll]: https://github.com/rust-lang/rust/pull/30663
[1.7m]: https://github.com/rust-lang/rust/pull/30381
[1.7p]: https://github.com/rust-lang/rust/pull/30681
[1.7rp]: https://github.com/rust-lang/rust/pull/29498
[1.7rpa]: https://github.com/rust-lang/rust/pull/30353
[1.7rr]: https://github.com/rust-lang/cargo/pull/2279
[1.7sf]: https://github.com/rust-lang/rust/pull/30389
[1.7utf8]: https://github.com/rust-lang/rust/pull/30740
[1.7v]: https://github.com/rust-lang/rust/pull/29973
[RFC 1214]: https://github.com/rust-lang/rfcs/blob/master/text/1214-projections-lifetimes-and-wf.md
[`BuildHasher::Hasher`]: http://doc.rust-lang.org/nightly/std/hash/trait.Hasher.html
[`BuildHasher::build_hasher`]: http://doc.rust-lang.org/nightly/std/hash/trait.BuildHasher.html#tymethod.build_hasher
[`CString::into_bytes_with_nul`]: http://doc.rust-lang.org/nightly/std/ffi/struct.CString.html#method.into_bytes_with_nul
[`CString::into_bytes`]: http://doc.rust-lang.org/nightly/std/ffi/struct.CString.html#method.into_bytes
[`CString::into_string`]: http://doc.rust-lang.org/nightly/std/ffi/struct.CString.html#method.into_string
[`HashMap::with_capacity_and_hasher`]: http://doc.rust-lang.org/nightly/std/collections/struct.HashMap.html#method.with_capacity_and_hasher
[`HashMap::with_hasher`]: http://doc.rust-lang.org/nightly/std/collections/struct.HashMap.html#method.with_hasher
[`HashSet::with_capacity_and_hasher`]: http://doc.rust-lang.org/nightly/std/collections/struct.HashSet.html#method.with_capacity_and_hasher
[`HashSet::with_hasher`]: http://doc.rust-lang.org/nightly/std/collections/struct.HashSet.html#method.with_hasher
[`IntoStringError::into_cstring`]: http://doc.rust-lang.org/nightly/std/ffi/struct.IntoStringError.html#method.into_cstring
[`IntoStringError::utf8_error`]: http://doc.rust-lang.org/nightly/std/ffi/struct.IntoStringError.html#method.utf8_error
[`Ipv4Addr::is_broadcast`]: http://doc.rust-lang.org/nightly/std/net/struct.Ipv4Addr.html#method.is_broadcast
[`Ipv4Addr::is_documentation`]: http://doc.rust-lang.org/nightly/std/net/struct.Ipv4Addr.html#method.is_documentation
[`Ipv4Addr::is_link_local`]: http://doc.rust-lang.org/nightly/std/net/struct.Ipv4Addr.html#method.is_link_local
[`Ipv4Addr::is_loopback`]: http://doc.rust-lang.org/nightly/std/net/struct.Ipv4Addr.html#method.is_loopback
[`Ipv4Addr::is_multicast`]: http://doc.rust-lang.org/nightly/std/net/struct.Ipv4Addr.html#method.is_multicast
[`Ipv4Addr::is_private`]: http://doc.rust-lang.org/nightly/std/net/struct.Ipv4Addr.html#method.is_private
[`Ipv6Addr::is_loopback`]: http://doc.rust-lang.org/nightly/std/net/struct.Ipv6Addr.html#method.is_loopback
[`Ipv6Addr::is_multicast`]: http://doc.rust-lang.org/nightly/std/net/struct.Ipv6Addr.html#method.is_multicast
[`Ipv6Addr::is_unspecified`]: http://doc.rust-lang.org/nightly/std/net/struct.Ipv6Addr.html#method.is_unspecified
[`Path::strip_prefix`]: http://doc.rust-lang.org/nightly/std/path/struct.Path.html#method.strip_prefix
[`RandomState::new`]: http://doc.rust-lang.org/nightly/std/collections/hash_map/struct.RandomState.html#method.new
[`String::as_mut_str`]: http://doc.rust-lang.org/nightly/std/string/struct.String.html#method.as_mut_str
[`String::as_str`]: http://doc.rust-lang.org/nightly/std/string/struct.String.html#method.as_str
[`Vec::as_mut_slice`]: http://doc.rust-lang.org/nightly/std/vec/struct.Vec.html#method.as_mut_slice
[`Vec::as_slice`]: http://doc.rust-lang.org/nightly/std/vec/struct.Vec.html#method.as_slice
[`clone_from_slice`]: http://doc.rust-lang.org/nightly/std/primitive.slice.html#method.clone_from_slice
[`ffi::IntoStringError`]: http://doc.rust-lang.org/nightly/std/ffi/struct.IntoStringError.html
[`i32::checked_neg`]: http://doc.rust-lang.org/nightly/std/primitive.i32.html#method.checked_neg
[`i32::checked_rem`]: http://doc.rust-lang.org/nightly/std/primitive.i32.html#method.checked_rem
[`i32::checked_shl`]: http://doc.rust-lang.org/nightly/std/primitive.i32.html#method.checked_shl
[`i32::checked_shr`]: http://doc.rust-lang.org/nightly/std/primitive.i32.html#method.checked_shr
[`i32::overflowing_add`]: http://doc.rust-lang.org/nightly/std/primitive.i32.html#method.overflowing_add
[`i32::overflowing_div`]: http://doc.rust-lang.org/nightly/std/primitive.i32.html#method.overflowing_div
[`i32::overflowing_mul`]: http://doc.rust-lang.org/nightly/std/primitive.i32.html#method.overflowing_mul
[`i32::overflowing_neg`]: http://doc.rust-lang.org/nightly/std/primitive.i32.html#method.overflowing_neg
[`i32::overflowing_rem`]: http://doc.rust-lang.org/nightly/std/primitive.i32.html#method.overflowing_rem
[`i32::overflowing_shl`]: http://doc.rust-lang.org/nightly/std/primitive.i32.html#method.overflowing_shl
[`i32::overflowing_shr`]: http://doc.rust-lang.org/nightly/std/primitive.i32.html#method.overflowing_shr
[`i32::overflowing_sub`]: http://doc.rust-lang.org/nightly/std/primitive.i32.html#method.overflowing_sub
[`i32::saturating_mul`]: http://doc.rust-lang.org/nightly/std/primitive.i32.html#method.saturating_mul
[`path::StripPrefixError`]: http://doc.rust-lang.org/nightly/std/path/struct.StripPrefixError.html
[`sort_by_key`]: http://doc.rust-lang.org/nightly/std/primitive.slice.html#method.sort_by_key
[`std::collections::hash_map::RandomState`]: http://doc.rust-lang.org/nightly/std/collections/hash_map/struct.RandomState.html
[`std::hash::BuildHasherDefault`]: http://doc.rust-lang.org/nightly/std/hash/struct.BuildHasherDefault.html
[`std::hash::BuildHasher`]: http://doc.rust-lang.org/nightly/std/hash/trait.BuildHasher.html
[`u32::checked_neg`]: http://doc.rust-lang.org/nightly/std/primitive.u32.html#method.checked_neg
[`u32::checked_rem`]: http://doc.rust-lang.org/nightly/std/primitive.u32.html#method.checked_rem
[`u32::checked_neg`]: http://doc.rust-lang.org/nightly/std/primitive.u32.html#method.checked_neg
[`u32::checked_shl`]: http://doc.rust-lang.org/nightly/std/primitive.u32.html#method.checked_shl
[`u32::overflowing_add`]: http://doc.rust-lang.org/nightly/std/primitive.u32.html#method.overflowing_add
[`u32::overflowing_div`]: http://doc.rust-lang.org/nightly/std/primitive.u32.html#method.overflowing_div
[`u32::overflowing_mul`]: http://doc.rust-lang.org/nightly/std/primitive.u32.html#method.overflowing_mul
[`u32::overflowing_neg`]: http://doc.rust-lang.org/nightly/std/primitive.u32.html#method.overflowing_neg
[`u32::overflowing_rem`]: http://doc.rust-lang.org/nightly/std/primitive.u32.html#method.overflowing_rem
[`u32::overflowing_shl`]: http://doc.rust-lang.org/nightly/std/primitive.u32.html#method.overflowing_shl
[`u32::overflowing_shr`]: http://doc.rust-lang.org/nightly/std/primitive.u32.html#method.overflowing_shr
[`u32::overflowing_sub`]: http://doc.rust-lang.org/nightly/std/primitive.u32.html#method.overflowing_sub
[`u32::saturating_mul`]: http://doc.rust-lang.org/nightly/std/primitive.u32.html#method.saturating_mul
Version 1.6.0 (2016-01-21)
==========================
Language
--------
* The `#![no_std]` attribute causes a crate to not be linked to the
standard library, but only the [core library][1.6co], as described
in [RFC 1184]. The core library defines common types and traits but
has no platform dependencies whatsoever, and is the basis for Rust
software in environments that cannot support a full port of the
standard library, such as operating systems. Most of the core
library is now stable.
Libraries
---------
* Stabilized APIs:
[`Read::read_exact`],
[`ErrorKind::UnexpectedEof`][] (renamed from `UnexpectedEOF`),
[`fs::DirBuilder`], [`fs::DirBuilder::new`],
[`fs::DirBuilder::recursive`], [`fs::DirBuilder::create`],
[`os::unix::fs::DirBuilderExt`],
[`os::unix::fs::DirBuilderExt::mode`], [`vec::Drain`],
[`vec::Vec::drain`], [`string::Drain`], [`string::String::drain`],
[`vec_deque::Drain`], [`vec_deque::VecDeque::drain`],
[`collections::hash_map::Drain`],
[`collections::hash_map::HashMap::drain`],
[`collections::hash_set::Drain`],
[`collections::hash_set::HashSet::drain`],
[`collections::binary_heap::Drain`],
[`collections::binary_heap::BinaryHeap::drain`],
[`Vec::extend_from_slice`][] (renamed from `push_all`),
[`Mutex::get_mut`], [`Mutex::into_inner`], [`RwLock::get_mut`],
[`RwLock::into_inner`],
[`Iterator::min_by_key`][] (renamed from `min_by`),
[`Iterator::max_by_key`][] (renamed from `max_by`).
* The [core library][1.6co] is stable, as are most of its APIs.
* [The `assert_eq!` macro supports arguments that don't implement
`Sized`][1.6ae], such as arrays. In this way it behaves more like
`assert!`.
* Several timer functions that take duration in milliseconds [are
deprecated in favor of those that take `Duration`][1.6ms]. These
include `Condvar::wait_timeout_ms`, `thread::sleep_ms`, and
`thread::park_timeout_ms`.
* The algorithm by which `Vec` reserves additional elements was
[tweaked to not allocate excessive space][1.6a] while still growing
exponentially.
* `From` conversions are [implemented from integers to floats][1.6f]
in cases where the conversion is lossless. Thus they are not
implemented for 32-bit ints to `f32`, nor for 64-bit ints to `f32`
or `f64`. They are also not implemented for `isize` and `usize`
because the implementations would be platform-specific. `From` is
also implemented from `f32` to `f64`.
* `From<&Path>` and `From<PathBuf>` are implemented for `Cow<Path>`.
* `From<T>` is implemented for `Box<T>`, `Rc<T>` and `Arc<T>`.
* `IntoIterator` is implemented for `&PathBuf` and `&Path`.
* [`BinaryHeap` was refactored][1.6bh] for modest performance
improvements.
* Sorting slices that are already sorted [is 50% faster in some
cases][1.6s].
Cargo
-----
* Cargo will look in `$CARGO_HOME/bin` for subcommands [by default][1.6c].
* Cargo build scripts can specify their dependencies by emitting the
[`rerun-if-changed`][1.6rr] key.
* crates.io will reject publication of crates with dependencies that
have a wildcard version constraint. Crates with wildcard
dependencies were seen to cause a variety of problems, as described
in [RFC 1241]. Since 1.5 publication of such crates has emitted a
warning.
* `cargo clean` [accepts a `--release` flag][1.6cc] to clean the
release folder. A variety of artifacts that Cargo failed to clean
are now correctly deleted.
Misc
----
* The `unreachable_code` lint [warns when a function call's argument
diverges][1.6dv].
* The parser indicates [failures that may be caused by
confusingly-similar Unicode characters][1.6uc]
* Certain macro errors [are reported at definition time][1.6m], not
expansion.
Compatibility Notes
-------------------
* The compiler no longer makes use of the [`RUST_PATH`][1.6rp]
environment variable when locating crates. This was a pre-cargo
feature for integrating with the package manager that was
accidentally never removed.
* [A number of bugs were fixed in the privacy checker][1.6p] that
could cause previously-accepted code to break.
* [Modules and unit/tuple structs may not share the same name][1.6ts].
* [Bugs in pattern matching unit structs were fixed][1.6us]. The tuple
struct pattern syntax (`Foo(..)`) can no longer be used to match
unit structs. This is a warning now, but will become an error in
future releases. Patterns that share the same name as a const are
now an error.
* A bug was fixed that causes [rustc not to apply default type
parameters][1.6xc] when resolving certain method implementations of
traits defined in other crates.
[1.6a]: https://github.com/rust-lang/rust/pull/29454
[1.6ae]: https://github.com/rust-lang/rust/pull/29770
[1.6bh]: https://github.com/rust-lang/rust/pull/29811
[1.6c]: https://github.com/rust-lang/cargo/pull/2192
[1.6cc]: https://github.com/rust-lang/cargo/pull/2131
[1.6co]: http://doc.rust-lang.org/beta/core/index.html
[1.6dv]: https://github.com/rust-lang/rust/pull/30000
[1.6f]: https://github.com/rust-lang/rust/pull/29129
[1.6m]: https://github.com/rust-lang/rust/pull/29828
[1.6ms]: https://github.com/rust-lang/rust/pull/29604
[1.6p]: https://github.com/rust-lang/rust/pull/29726
[1.6rp]: https://github.com/rust-lang/rust/pull/30034
[1.6rr]: https://github.com/rust-lang/cargo/pull/2134
[1.6s]: https://github.com/rust-lang/rust/pull/29675
[1.6ts]: https://github.com/rust-lang/rust/issues/21546
[1.6uc]: https://github.com/rust-lang/rust/pull/29837
[1.6us]: https://github.com/rust-lang/rust/pull/29383
[1.6xc]: https://github.com/rust-lang/rust/issues/30123
[RFC 1184]: https://github.com/rust-lang/rfcs/blob/master/text/1184-stabilize-no_std.md
[RFC 1241]: https://github.com/rust-lang/rfcs/blob/master/text/1241-no-wildcard-deps.md
[`ErrorKind::UnexpectedEof`]: http://doc.rust-lang.org/nightly/std/io/enum.ErrorKind.html#variant.UnexpectedEof
[`Iterator::max_by_key`]: http://doc.rust-lang.org/nightly/std/iter/trait.Iterator.html#method.max_by_key
[`Iterator::min_by_key`]: http://doc.rust-lang.org/nightly/std/iter/trait.Iterator.html#method.min_by_key
[`Mutex::get_mut`]: http://doc.rust-lang.org/nightly/std/sync/struct.Mutex.html#method.get_mut
[`Mutex::into_inner`]: http://doc.rust-lang.org/nightly/std/sync/struct.Mutex.html#method.into_inner
[`Read::read_exact`]: http://doc.rust-lang.org/nightly/std/io/trait.Read.html#method.read_exact
[`RwLock::get_mut`]: http://doc.rust-lang.org/nightly/std/sync/struct.RwLock.html#method.get_mut
[`RwLock::into_inner`]: http://doc.rust-lang.org/nightly/std/sync/struct.RwLock.html#method.into_inner
[`Vec::extend_from_slice`]: http://doc.rust-lang.org/nightly/collections/vec/struct.Vec.html#method.extend_from_slice
[`collections::binary_heap::BinaryHeap::drain`]: http://doc.rust-lang.org/nightly/std/collections/binary_heap/struct.BinaryHeap.html#method.drain
[`collections::binary_heap::Drain`]: http://doc.rust-lang.org/nightly/std/collections/binary_heap/struct.Drain.html
[`collections::hash_map::Drain`]: http://doc.rust-lang.org/nightly/std/collections/hash_map/struct.Drain.html
[`collections::hash_map::HashMap::drain`]: http://doc.rust-lang.org/nightly/std/collections/hash_map/struct.HashMap.html#method.drain
[`collections::hash_set::Drain`]: http://doc.rust-lang.org/nightly/std/collections/hash_set/struct.Drain.html
[`collections::hash_set::HashSet::drain`]: http://doc.rust-lang.org/nightly/std/collections/hash_set/struct.HashSet.html#method.drain
[`fs::DirBuilder::create`]: http://doc.rust-lang.org/nightly/std/fs/struct.DirBuilder.html#method.create
[`fs::DirBuilder::new`]: http://doc.rust-lang.org/nightly/std/fs/struct.DirBuilder.html#method.new
[`fs::DirBuilder::recursive`]: http://doc.rust-lang.org/nightly/std/fs/struct.DirBuilder.html#method.recursive
[`fs::DirBuilder`]: http://doc.rust-lang.org/nightly/std/fs/struct.DirBuilder.html
[`os::unix::fs::DirBuilderExt::mode`]: http://doc.rust-lang.org/nightly/std/os/unix/fs/trait.DirBuilderExt.html#tymethod.mode
[`os::unix::fs::DirBuilderExt`]: http://doc.rust-lang.org/nightly/std/os/unix/fs/trait.DirBuilderExt.html
[`string::Drain`]: http://doc.rust-lang.org/nightly/std/string/struct.Drain.html
[`string::String::drain`]: http://doc.rust-lang.org/nightly/std/string/struct.String.html#method.drain
[`vec::Drain`]: http://doc.rust-lang.org/nightly/std/vec/struct.Drain.html
[`vec::Vec::drain`]: http://doc.rust-lang.org/nightly/std/vec/struct.Vec.html#method.drain
[`vec_deque::Drain`]: http://doc.rust-lang.org/nightly/std/collections/vec_deque/struct.Drain.html
[`vec_deque::VecDeque::drain`]: http://doc.rust-lang.org/nightly/std/collections/vec_deque/struct.VecDeque.html#method.drain
Version 1.5.0 (2015-12-10)
==========================
* ~700 changes, numerous bugfixes
Highlights
----------
* Stabilized APIs:
[`BinaryHeap::from`], [`BinaryHeap::into_sorted_vec`],
[`BinaryHeap::into_vec`], [`Condvar::wait_timeout`],
[`FileTypeExt::is_block_device`], [`FileTypeExt::is_char_device`],
[`FileTypeExt::is_fifo`], [`FileTypeExt::is_socket`],
[`FileTypeExt`], [`Formatter::alternate`], [`Formatter::fill`],
[`Formatter::precision`], [`Formatter::sign_aware_zero_pad`],
[`Formatter::sign_minus`], [`Formatter::sign_plus`],
[`Formatter::width`], [`Iterator::cmp`], [`Iterator::eq`],
[`Iterator::ge`], [`Iterator::gt`], [`Iterator::le`],
[`Iterator::lt`], [`Iterator::ne`], [`Iterator::partial_cmp`],
[`Path::canonicalize`], [`Path::exists`], [`Path::is_dir`],
[`Path::is_file`], [`Path::metadata`], [`Path::read_dir`],
[`Path::read_link`], [`Path::symlink_metadata`],
[`Utf8Error::valid_up_to`], [`Vec::resize`],
[`VecDeque::as_mut_slices`], [`VecDeque::as_slices`],
[`VecDeque::insert`], [`VecDeque::shrink_to_fit`],
[`VecDeque::swap_remove_back`], [`VecDeque::swap_remove_front`],
[`slice::split_first_mut`], [`slice::split_first`],
[`slice::split_last_mut`], [`slice::split_last`],
[`char::from_u32_unchecked`], [`fs::canonicalize`],
[`str::MatchIndices`], [`str::RMatchIndices`],
[`str::match_indices`], [`str::rmatch_indices`],
[`str::slice_mut_unchecked`], [`string::ParseError`].
* Rust applications hosted on crates.io can be installed locally to
`~/.cargo/bin` with the [`cargo install`] command. Among other
things this makes it easier to augment Cargo with new subcommands:
when a binary named e.g. `cargo-foo` is found in `$PATH` it can be
invoked as `cargo foo`.
* Crates with wildcard (`*`) dependencies will [emit warnings when
published][1.5w]. In 1.6 it will no longer be possible to publish
crates with wildcard dependencies.
Breaking Changes
----------------
* The rules determining when a particular lifetime must outlive
a particular value (known as '[dropck]') have been [modified
to not rely on parametricity][1.5p].
* [Implementations of `AsRef` and `AsMut` were added to `Box`, `Rc`,
and `Arc`][1.5a]. Because these smart pointer types implement
`Deref`, this causes breakage in cases where the interior type
contains methods of the same name.
* [Correct a bug in Rc/Arc][1.5c] that caused [dropck] to be unaware
that they could drop their content. Soundness fix.
* All method invocations are [properly checked][1.5wf1] for
[well-formedness][1.5wf2]. Soundness fix.
* Traits whose supertraits contain `Self` are [not object
safe][1.5o]. Soundness fix.
* Target specifications support a [`no_default_libraries`][1.5nd]
setting that controls whether `-nodefaultlibs` is passed to the
linker, and in turn the `is_like_windows` setting no longer affects
the `-nodefaultlibs` flag.
* `#[derive(Show)]`, long-deprecated, [has been removed][1.5ds].
* The `#[inline]` and `#[repr]` attributes [can only appear
in valid locations][1.5at].
* Native libraries linked from the local crate are [passed to
the linker before native libraries from upstream crates][1.5nl].
* Two rarely-used attributes, `#[no_debug]` and
`#[omit_gdb_pretty_printer_section]` [are feature gated][1.5fg].
* Negation of unsigned integers, which has been a warning for
several releases, [is now behind a feature gate and will
generate errors][1.5nu].
* The parser accidentally accepted visibility modifiers on
enum variants, a bug [which has been fixed][1.5ev].
* [A bug was fixed that allowed `use` statements to import unstable
features][1.5use].
Language
--------
* When evaluating expressions at compile-time that are not
compile-time constants (const-evaluating expressions in non-const
contexts), incorrect code such as overlong bitshifts and arithmetic
overflow will [generate a warning instead of an error][1.5ce],
delaying the error until runtime. This will allow the
const-evaluator to be expanded in the future backwards-compatibly.
* The `improper_ctypes` lint [no longer warns about using `isize` and
`usize` in FFI][1.5ict].
Libraries
---------
* `Arc<T>` and `Rc<T>` are [covariant with respect to `T` instead of
invariant][1.5c].
* `Default` is [implemented for mutable slices][1.5d].
* `FromStr` is [implemented for `SockAddrV4` and `SockAddrV6`][1.5s].
* There are now `From` conversions [between floating point
types][1.5f] where the conversions are lossless.
* There are now `From` conversions [between integer types][1.5i] where
the conversions are lossless.
* [`fs::Metadata` implements `Clone`][1.5fs].
* The `parse` method [accepts a leading "+" when parsing
integers][1.5pi].
* [`AsMut` is implemented for `Vec`][1.5am].
* The `clone_from` implementations for `String` and `BinaryHeap` [have
been optimized][1.5cf] and no longer rely on the default impl.
* The `extern "Rust"`, `extern "C"`, `unsafe extern "Rust"` and
`unsafe extern "C"` function types now [implement `Clone`,
`PartialEq`, `Eq`, `PartialOrd`, `Ord`, `Hash`, `fmt::Pointer`, and
`fmt::Debug` for up to 12 arguments][1.5fp].
* [Dropping `Vec`s is much faster in unoptimized builds when the
element types don't implement `Drop`][1.5dv].
* A bug that caused in incorrect behavior when [combining `VecDeque`
with zero-sized types][1.5vdz] was resolved.
* [`PartialOrd` for slices is faster][1.5po].
Miscellaneous
-------------
* [Crate metadata size was reduced by 20%][1.5md].
* [Improvements to code generation reduced the size of libcore by 3.3
MB and rustc's memory usage by 18MB][1.5m].
* [Improvements to deref translation increased performance in
unoptimized builds][1.5dr].
* Various errors in trait resolution [are deduplicated to only be
reported once][1.5te].
* Rust has preliminary [support for rumprun kernels][1.5rr].
* Rust has preliminary [support for NetBSD on amd64][1.5na].
[1.5use]: https://github.com/rust-lang/rust/pull/28364
[1.5po]: https://github.com/rust-lang/rust/pull/28436
[1.5ev]: https://github.com/rust-lang/rust/pull/28442
[1.5nu]: https://github.com/rust-lang/rust/pull/28468
[1.5dr]: https://github.com/rust-lang/rust/pull/28491
[1.5vdz]: https://github.com/rust-lang/rust/pull/28494
[1.5md]: https://github.com/rust-lang/rust/pull/28521
[1.5fg]: https://github.com/rust-lang/rust/pull/28522
[1.5dv]: https://github.com/rust-lang/rust/pull/28531
[1.5na]: https://github.com/rust-lang/rust/pull/28543
[1.5fp]: https://github.com/rust-lang/rust/pull/28560
[1.5rr]: https://github.com/rust-lang/rust/pull/28593
[1.5cf]: https://github.com/rust-lang/rust/pull/28602
[1.5nl]: https://github.com/rust-lang/rust/pull/28605
[1.5te]: https://github.com/rust-lang/rust/pull/28645
[1.5at]: https://github.com/rust-lang/rust/pull/28650
[1.5am]: https://github.com/rust-lang/rust/pull/28663
[1.5m]: https://github.com/rust-lang/rust/pull/28778
[1.5ict]: https://github.com/rust-lang/rust/pull/28779
[1.5a]: https://github.com/rust-lang/rust/pull/28811
[1.5pi]: https://github.com/rust-lang/rust/pull/28826
[1.5ce]: https://github.com/rust-lang/rfcs/blob/master/text/1229-compile-time-asserts.md
[1.5p]: https://github.com/rust-lang/rfcs/blob/master/text/1238-nonparametric-dropck.md
[1.5i]: https://github.com/rust-lang/rust/pull/28921
[1.5fs]: https://github.com/rust-lang/rust/pull/29021
[1.5f]: https://github.com/rust-lang/rust/pull/29129
[1.5ds]: https://github.com/rust-lang/rust/pull/29148
[1.5s]: https://github.com/rust-lang/rust/pull/29190
[1.5d]: https://github.com/rust-lang/rust/pull/29245
[1.5o]: https://github.com/rust-lang/rust/pull/29259
[1.5nd]: https://github.com/rust-lang/rust/pull/28578
[1.5wf2]: https://github.com/rust-lang/rfcs/blob/master/text/1214-projections-lifetimes-and-wf.md
[1.5wf1]: https://github.com/rust-lang/rust/pull/28669
[dropck]: https://doc.rust-lang.org/nightly/nomicon/dropck.html
[1.5c]: https://github.com/rust-lang/rust/pull/29110
[1.5w]: https://github.com/rust-lang/rfcs/blob/master/text/1241-no-wildcard-deps.md
[`cargo install`]: https://github.com/rust-lang/rfcs/blob/master/text/1200-cargo-install.md
[`BinaryHeap::from`]: http://doc.rust-lang.org/nightly/std/convert/trait.From.html#method.from
[`BinaryHeap::into_sorted_vec`]: http://doc.rust-lang.org/nightly/std/collections/struct.BinaryHeap.html#method.into_sorted_vec
[`BinaryHeap::into_vec`]: http://doc.rust-lang.org/nightly/std/collections/struct.BinaryHeap.html#method.into_vec
[`Condvar::wait_timeout`]: http://doc.rust-lang.org/nightly/std/sync/struct.Condvar.html#method.wait_timeout
[`FileTypeExt::is_block_device`]: http://doc.rust-lang.org/nightly/std/os/unix/fs/trait.FileTypeExt.html#tymethod.is_block_device
[`FileTypeExt::is_char_device`]: http://doc.rust-lang.org/nightly/std/os/unix/fs/trait.FileTypeExt.html#tymethod.is_char_device
[`FileTypeExt::is_fifo`]: http://doc.rust-lang.org/nightly/std/os/unix/fs/trait.FileTypeExt.html#tymethod.is_fifo
[`FileTypeExt::is_socket`]: http://doc.rust-lang.org/nightly/std/os/unix/fs/trait.FileTypeExt.html#tymethod.is_socket
[`FileTypeExt`]: http://doc.rust-lang.org/nightly/std/os/unix/fs/trait.FileTypeExt.html
[`Formatter::alternate`]: http://doc.rust-lang.org/nightly/core/fmt/struct.Formatter.html#method.alternate
[`Formatter::fill`]: http://doc.rust-lang.org/nightly/core/fmt/struct.Formatter.html#method.fill
[`Formatter::precision`]: http://doc.rust-lang.org/nightly/core/fmt/struct.Formatter.html#method.precision
[`Formatter::sign_aware_zero_pad`]: http://doc.rust-lang.org/nightly/core/fmt/struct.Formatter.html#method.sign_aware_zero_pad
[`Formatter::sign_minus`]: http://doc.rust-lang.org/nightly/core/fmt/struct.Formatter.html#method.sign_minus
[`Formatter::sign_plus`]: http://doc.rust-lang.org/nightly/core/fmt/struct.Formatter.html#method.sign_plus
[`Formatter::width`]: http://doc.rust-lang.org/nightly/core/fmt/struct.Formatter.html#method.width
[`Iterator::cmp`]: http://doc.rust-lang.org/nightly/core/iter/trait.Iterator.html#method.cmp
[`Iterator::eq`]: http://doc.rust-lang.org/nightly/core/iter/trait.Iterator.html#method.eq
[`Iterator::ge`]: http://doc.rust-lang.org/nightly/core/iter/trait.Iterator.html#method.ge
[`Iterator::gt`]: http://doc.rust-lang.org/nightly/core/iter/trait.Iterator.html#method.gt
[`Iterator::le`]: http://doc.rust-lang.org/nightly/core/iter/trait.Iterator.html#method.le
[`Iterator::lt`]: http://doc.rust-lang.org/nightly/core/iter/trait.Iterator.html#method.lt
[`Iterator::ne`]: http://doc.rust-lang.org/nightly/core/iter/trait.Iterator.html#method.ne
[`Iterator::partial_cmp`]: http://doc.rust-lang.org/nightly/core/iter/trait.Iterator.html#method.partial_cmp
[`Path::canonicalize`]: http://doc.rust-lang.org/nightly/std/path/struct.Path.html#method.canonicalize
[`Path::exists`]: http://doc.rust-lang.org/nightly/std/path/struct.Path.html#method.exists
[`Path::is_dir`]: http://doc.rust-lang.org/nightly/std/path/struct.Path.html#method.is_dir
[`Path::is_file`]: http://doc.rust-lang.org/nightly/std/path/struct.Path.html#method.is_file
[`Path::metadata`]: http://doc.rust-lang.org/nightly/std/path/struct.Path.html#method.metadata
[`Path::read_dir`]: http://doc.rust-lang.org/nightly/std/path/struct.Path.html#method.read_dir
[`Path::read_link`]: http://doc.rust-lang.org/nightly/std/path/struct.Path.html#method.read_link
[`Path::symlink_metadata`]: http://doc.rust-lang.org/nightly/std/path/struct.Path.html#method.symlink_metadata
[`Utf8Error::valid_up_to`]: http://doc.rust-lang.org/nightly/core/str/struct.Utf8Error.html#method.valid_up_to
[`Vec::resize`]: http://doc.rust-lang.org/nightly/std/vec/struct.Vec.html#method.resize
[`VecDeque::as_mut_slices`]: http://doc.rust-lang.org/nightly/std/collections/struct.VecDeque.html#method.as_mut_slices
[`VecDeque::as_slices`]: http://doc.rust-lang.org/nightly/std/collections/struct.VecDeque.html#method.as_slices
[`VecDeque::insert`]: http://doc.rust-lang.org/nightly/std/collections/struct.VecDeque.html#method.insert
[`VecDeque::shrink_to_fit`]: http://doc.rust-lang.org/nightly/std/collections/struct.VecDeque.html#method.shrink_to_fit
[`VecDeque::swap_remove_back`]: http://doc.rust-lang.org/nightly/std/collections/struct.VecDeque.html#method.swap_remove_back
[`VecDeque::swap_remove_front`]: http://doc.rust-lang.org/nightly/std/collections/struct.VecDeque.html#method.swap_remove_front
[`slice::split_first_mut`]: http://doc.rust-lang.org/nightly/std/primitive.slice.html#method.split_first_mut
[`slice::split_first`]: http://doc.rust-lang.org/nightly/std/primitive.slice.html#method.split_first
[`slice::split_last_mut`]: http://doc.rust-lang.org/nightly/std/primitive.slice.html#method.split_last_mut
[`slice::split_last`]: http://doc.rust-lang.org/nightly/std/primitive.slice.html#method.split_last
[`char::from_u32_unchecked`]: http://doc.rust-lang.org/nightly/std/char/fn.from_u32_unchecked.html
[`fs::canonicalize`]: http://doc.rust-lang.org/nightly/std/fs/fn.canonicalize.html
[`str::MatchIndices`]: http://doc.rust-lang.org/nightly/std/str/struct.MatchIndices.html
[`str::RMatchIndices`]: http://doc.rust-lang.org/nightly/std/str/struct.RMatchIndices.html
[`str::match_indices`]: http://doc.rust-lang.org/nightly/std/primitive.str.html#method.match_indices
[`str::rmatch_indices`]: http://doc.rust-lang.org/nightly/std/primitive.str.html#method.rmatch_indices
[`str::slice_mut_unchecked`]: http://doc.rust-lang.org/nightly/std/primitive.str.html#method.slice_mut_unchecked
[`string::ParseError`]: http://doc.rust-lang.org/nightly/std/string/enum.ParseError.html
Version 1.4.0 (2015-10-29)
==========================
* ~1200 changes, numerous bugfixes
Highlights
----------
* Windows builds targeting the 64-bit MSVC ABI and linker (instead of
GNU) are now supported and recommended for use.
Breaking Changes
----------------
* [Several changes have been made to fix type soundness and improve
the behavior of associated types][sound]. See [RFC 1214]. Although
we have mostly introduced these changes as warnings this release, to
become errors next release, there are still some scenarios that will
see immediate breakage.
* [The `str::lines` and `BufRead::lines` iterators treat `\r\n` as
line breaks in addition to `\n`][crlf].
* [Loans of `'static` lifetime extend to the end of a function][stat].
* [`str::parse` no longer introduces avoidable rounding error when
parsing floating point numbers. Together with earlier changes to
float formatting/output, "round trips" like f.to_string().parse()
now preserve the value of f exactly. Additionally, leading plus
signs are now accepted][fp3].
Language
--------
* `use` statements that import multiple items [can now rename
them][i], as in `use foo::{bar as kitten, baz as puppy}`.
* [Binops work correctly on fat pointers][binfat].
* `pub extern crate`, which does not behave as expected, [issues a
warning][pec] until a better solution is found.
Libraries
---------
* [Many APIs were stabilized][stab]: `<Box<str>>::into_string`,
[`Arc::downgrade`], [`Arc::get_mut`], [`Arc::make_mut`],
[`Arc::try_unwrap`], [`Box::from_raw`], [`Box::into_raw`], [`CStr::to_str`],
[`CStr::to_string_lossy`], [`CString::from_raw`], [`CString::into_raw`],
[`IntoRawFd::into_raw_fd`], [`IntoRawFd`],
`IntoRawHandle::into_raw_handle`, `IntoRawHandle`,
`IntoRawSocket::into_raw_socket`, `IntoRawSocket`, [`Rc::downgrade`],
[`Rc::get_mut`], [`Rc::make_mut`], [`Rc::try_unwrap`], [`Result::expect`],
[`String::into_boxed_str`], [`TcpStream::read_timeout`],
[`TcpStream::set_read_timeout`], [`TcpStream::set_write_timeout`],
[`TcpStream::write_timeout`], [`UdpSocket::read_timeout`],
[`UdpSocket::set_read_timeout`], [`UdpSocket::set_write_timeout`],
[`UdpSocket::write_timeout`], `Vec::append`, `Vec::split_off`,
[`VecDeque::append`], [`VecDeque::retain`], [`VecDeque::split_off`],
[`rc::Weak::upgrade`], [`rc::Weak`], [`slice::Iter::as_slice`],
[`slice::IterMut::into_slice`], [`str::CharIndices::as_str`],
[`str::Chars::as_str`], [`str::split_at_mut`], [`str::split_at`],
[`sync::Weak::upgrade`], [`sync::Weak`], [`thread::park_timeout`],
[`thread::sleep`].
* [Some APIs were deprecated][dep]: `BTreeMap::with_b`,
`BTreeSet::with_b`, `Option::as_mut_slice`, `Option::as_slice`,
`Result::as_mut_slice`, `Result::as_slice`, `f32::from_str_radix`,
`f64::from_str_radix`.
* [Reverse-searching strings is faster with the 'two-way'
algorithm][s].
* [`std::io::copy` allows `?Sized` arguments][cc].
* The `Windows`, `Chunks`, and `ChunksMut` iterators over slices all
[override `count`, `nth` and `last` with an O(1)
implementation][it].
* [`Default` is implemented for arrays up to `[T; 32]`][d].
* [`IntoRawFd` has been added to the Unix-specific prelude,
`IntoRawSocket` and `IntoRawHandle` to the Windows-specific
prelude][pr].
* [`Extend<String>` and `FromIterator<String` are both implemented for
`String`][es].
* [`IntoIterator` is implemented for references to `Option` and
`Result`][into2].
* [`HashMap` and `HashSet` implement `Extend<&T>` where `T:
Copy`][ext] as part of [RFC 839]. This will cause type inference
breakage in rare situations.
* [`BinaryHeap` implements `Debug`][bh2].
* [`Borrow` and `BorrowMut` are implemented for fixed-size
arrays][bm].
* [`extern fn`s with the "Rust" and "C" ABIs implement common
traits including `Eq`, `Ord`, `Debug`, `Hash`][fp].
* [String comparison is faster][faststr].
* `&mut T` where `T: std::fmt::Write` [also implements
`std::fmt::Write`][mutw].
* [A stable regression in `VecDeque::push_back` and other
capacity-altering methods that caused panics for zero-sized types
was fixed][vd].
* [Function pointers implement traits for up to 12 parameters][fp2].
Miscellaneous
-------------
* The compiler [no longer uses the 'morestack' feature to prevent
stack overflow][mm]. Instead it uses guard pages and stack
probes (though stack probes are not yet implemented on any platform
but Windows).
* [The compiler matches traits faster when projections are involved][p].
* The 'improper_ctypes' lint [no longer warns about use of `isize` and
`usize`][ffi].
* [Cargo now displays useful information about what its doing during
`cargo update`][cu].
[`Arc::downgrade`]: http://doc.rust-lang.org/nightly/alloc/arc/struct.Arc.html#method.downgrade
[`Arc::make_mut`]: http://doc.rust-lang.org/nightly/alloc/arc/struct.Arc.html#method.make_mut
[`Arc::get_mut`]: http://doc.rust-lang.org/nightly/alloc/arc/struct.Arc.html#method.get_mut
[`Arc::try_unwrap`]: http://doc.rust-lang.org/nightly/alloc/arc/struct.Arc.html#method.try_unwrap
[`Box::from_raw`]: http://doc.rust-lang.org/nightly/alloc/boxed/struct.Box.html#method.from_raw
[`Box::into_raw`]: http://doc.rust-lang.org/nightly/alloc/boxed/struct.Box.html#method.into_raw
[`CStr::to_str`]: http://doc.rust-lang.org/nightly/std/ffi/struct.CStr.html#method.to_str
[`CStr::to_string_lossy`]: http://doc.rust-lang.org/nightly/std/ffi/struct.CStr.html#method.to_string_lossy
[`CString::from_raw`]: http://doc.rust-lang.org/nightly/std/ffi/struct.CString.html#method.from_raw
[`CString::into_raw`]: http://doc.rust-lang.org/nightly/std/ffi/struct.CString.html#method.into_raw
[`IntoRawFd::into_raw_fd`]: http://doc.rust-lang.org/nightly/std/os/unix/io/trait.IntoRawFd.html#tymethod.into_raw_fd
[`IntoRawFd`]: http://doc.rust-lang.org/nightly/std/os/unix/io/trait.IntoRawFd.html
[`Rc::downgrade`]: http://doc.rust-lang.org/nightly/alloc/rc/struct.Rc.html#method.downgrade
[`Rc::get_mut`]: http://doc.rust-lang.org/nightly/alloc/rc/struct.Rc.html#method.get_mut
[`Rc::make_mut`]: http://doc.rust-lang.org/nightly/alloc/rc/struct.Rc.html#method.make_mut
[`Rc::try_unwrap`]: http://doc.rust-lang.org/nightly/alloc/rc/struct.Rc.html#method.try_unwrap
[`Result::expect`]: http://doc.rust-lang.org/nightly/core/result/enum.Result.html#method.expect
[`String::into_boxed_str`]: http://doc.rust-lang.org/nightly/collections/string/struct.String.html#method.into_boxed_str
[`TcpStream::read_timeout`]: http://doc.rust-lang.org/nightly/std/net/struct.TcpStream.html#method.read_timeout
[`TcpStream::set_read_timeout`]: http://doc.rust-lang.org/nightly/std/net/struct.TcpStream.html#method.set_read_timeout
[`TcpStream::write_timeout`]: http://doc.rust-lang.org/nightly/std/net/struct.TcpStream.html#method.write_timeout
[`TcpStream::set_write_timeout`]: http://doc.rust-lang.org/nightly/std/net/struct.TcpStream.html#method.set_write_timeout
[`UdpSocket::read_timeout`]: http://doc.rust-lang.org/nightly/std/net/struct.TcpStream.html#method.read_timeout
[`UdpSocket::set_read_timeout`]: http://doc.rust-lang.org/nightly/std/net/struct.TcpStream.html#method.set_read_timeout
[`UdpSocket::write_timeout`]: http://doc.rust-lang.org/nightly/std/net/struct.TcpStream.html#method.write_timeout
[`UdpSocket::set_write_timeout`]: http://doc.rust-lang.org/nightly/std/net/struct.TcpStream.html#method.set_write_timeout
[`VecDeque::append`]: http://doc.rust-lang.org/nightly/std/collections/struct.VecDeque.html#method.append
[`VecDeque::retain`]: http://doc.rust-lang.org/nightly/std/collections/struct.VecDeque.html#method.retain
[`VecDeque::split_off`]: http://doc.rust-lang.org/nightly/std/collections/struct.VecDeque.html#method.split_off
[`rc::Weak::upgrade`]: http://doc.rust-lang.org/nightly/std/rc/struct.Weak.html#method.upgrade
[`rc::Weak`]: http://doc.rust-lang.org/nightly/std/rc/struct.Weak.html
[`slice::Iter::as_slice`]: http://doc.rust-lang.org/nightly/std/slice/struct.Iter.html#method.as_slice
[`slice::IterMut::into_slice`]: http://doc.rust-lang.org/nightly/std/slice/struct.IterMut.html#method.into_slice
[`str::CharIndices::as_str`]: http://doc.rust-lang.org/nightly/std/str/struct.CharIndices.html#method.as_str
[`str::Chars::as_str`]: http://doc.rust-lang.org/nightly/std/str/struct.Chars.html#method.as_str
[`str::split_at_mut`]: http://doc.rust-lang.org/nightly/std/primitive.str.html#method.split_at_mut
[`str::split_at`]: http://doc.rust-lang.org/nightly/std/primitive.str.html#method.split_at
[`sync::Weak::upgrade`]: http://doc.rust-lang.org/nightly/std/sync/struct.Weak.html#method.upgrade
[`sync::Weak`]: http://doc.rust-lang.org/nightly/std/sync/struct.Weak.html
[`thread::park_timeout`]: http://doc.rust-lang.org/nightly/std/thread/fn.park_timeout.html
[`thread::sleep`]: http://doc.rust-lang.org/nightly/std/thread/fn.sleep.html
[bh2]: https://github.com/rust-lang/rust/pull/28156
[binfat]: https://github.com/rust-lang/rust/pull/28270
[bm]: https://github.com/rust-lang/rust/pull/28197
[cc]: https://github.com/rust-lang/rust/pull/27531
[crlf]: https://github.com/rust-lang/rust/pull/28034
[cu]: https://github.com/rust-lang/cargo/pull/1931
[d]: https://github.com/rust-lang/rust/pull/27825
[dep]: https://github.com/rust-lang/rust/pull/28339
[es]: https://github.com/rust-lang/rust/pull/27956
[ext]: https://github.com/rust-lang/rust/pull/28094
[faststr]: https://github.com/rust-lang/rust/pull/28338
[ffi]: https://github.com/rust-lang/rust/pull/28779
[fp]: https://github.com/rust-lang/rust/pull/28268
[fp2]: https://github.com/rust-lang/rust/pull/28560
[fp3]: https://github.com/rust-lang/rust/pull/27307
[i]: https://github.com/rust-lang/rust/pull/27451
[into2]: https://github.com/rust-lang/rust/pull/28039
[it]: https://github.com/rust-lang/rust/pull/27652
[mm]: https://github.com/rust-lang/rust/pull/27338
[mutw]: https://github.com/rust-lang/rust/pull/28368
[sound]: https://github.com/rust-lang/rust/pull/27641
[p]: https://github.com/rust-lang/rust/pull/27866
[pec]: https://github.com/rust-lang/rust/pull/28486
[pr]: https://github.com/rust-lang/rust/pull/27896
[RFC 839]: https://github.com/rust-lang/rfcs/blob/master/text/0839-embrace-extend-extinguish.md
[RFC 1214]: https://github.com/rust-lang/rfcs/blob/master/text/1214-projections-lifetimes-and-wf.md
[s]: https://github.com/rust-lang/rust/pull/27474
[stab]: https://github.com/rust-lang/rust/pull/28339
[stat]: https://github.com/rust-lang/rust/pull/28321
[vd]: https://github.com/rust-lang/rust/pull/28494
Version 1.3.0 (2015-09-17)
==============================
* ~900 changes, numerous bugfixes
Highlights
----------
* The [new object lifetime defaults][nold] have been [turned
on][nold2] after a cycle of warnings about the change. Now types
like `&'a Box<Trait>` (or `&'a Rc<Trait>`, etc) will change from
being interpreted as `&'a Box<Trait+'a>` to `&'a
Box<Trait+'static>`.
* [The Rustonomicon][nom] is a new book in the official documentation
that dives into writing unsafe Rust.
* The [`Duration`] API, [has been stabilized][ds]. This basic unit of
timekeeping is employed by other std APIs, as well as out-of-tree
time crates.
Breaking Changes
----------------
* The [new object lifetime defaults][nold] have been [turned
on][nold2] after a cycle of warnings about the change.
* There is a known [regression][lr] in how object lifetime elision is
interpreted, the proper solution for which is undetermined.
* The `#[prelude_import]` attribute, an internal implementation
detail, was accidentally stabilized previously. [It has been put
behind the `prelude_import` feature gate][pi]. This change is
believed to break no existing code.
* The behavior of [`size_of_val`][dst1] and [`align_of_val`][dst2] is
[more sane for dynamically sized types][dst3]. Code that relied on
the previous behavior is thought to be broken.
* The `dropck` rules, which checks that destructors can't access
destroyed values, [have been updated][dropck] to match the
[RFC][dropckrfc]. This fixes some soundness holes, and as such will
cause some previously-compiling code to no longer build.
Language
--------
* The [new object lifetime defaults][nold] have been [turned
on][nold2] after a cycle of warnings about the change.
* Semicolons may [now follow types and paths in
macros](https://github.com/rust-lang/rust/pull/27000).
* The behavior of [`size_of_val`][dst1] and [`align_of_val`][dst2] is
[more sane for dynamically sized types][dst3]. Code that relied on
the previous behavior is not known to exist, and suspected to be
broken.
* `'static` variables [may now be recursive][st].
* `ref` bindings choose between [`Deref`] and [`DerefMut`]
implementations correctly.
* The `dropck` rules, which checks that destructors can't access
destroyed values, [have been updated][dropck] to match the
[RFC][dropckrfc].
Libraries
---------
* The [`Duration`] API, [has been stabilized][ds], as well as the
`std::time` module, which presently contains only `Duration`.
* `Box<str>` and `Box<[T]>` both implement `Clone`.
* The owned C string, [`CString`], implements [`Borrow`] and the
borrowed C string, [`CStr`], implements [`ToOwned`]. The two of
these allow C strings to be borrowed and cloned in generic code.
* [`CStr`] implements [`Debug`].
* [`AtomicPtr`] implements [`Debug`].
* [`Error`] trait objects [can be downcast to their concrete types][e]
in many common configurations, using the [`is`], [`downcast`],
[`downcast_ref`] and [`downcast_mut`] methods, similarly to the
[`Any`] trait.
* Searching for substrings now [employs the two-way algorithm][search]
instead of doing a naive search. This gives major speedups to a
number of methods, including [`contains`][sc], [`find`][sf],
[`rfind`][srf], [`split`][ss]. [`starts_with`][ssw] and
[`ends_with`][sew] are also faster.
* The performance of `PartialEq` for slices is [much faster][ps].
* The [`Hash`] trait offers the default method, [`hash_slice`], which
is overridden and optimized by the implementations for scalars.
* The [`Hasher`] trait now has a number of specialized `write_*`
methods for primitive types, for efficiency.
* The I/O-specific error type, [`std::io::Error`][ie], gained a set of
methods for accessing the 'inner error', if any: [`get_ref`][iegr],
[`get_mut`][iegm], [`into_inner`][ieii]. As well, the implementation
of [`std::error::Error::cause`][iec] also delegates to the inner
error.
* [`process::Child`][pc] gained the [`id`] method, which returns a
`u32` representing the platform-specific process identifier.
* The [`connect`] method on slices is deprecated, replaced by the new
[`join`] method (note that both of these are on the *unstable*
[`SliceConcatExt`] trait, but through the magic of the prelude are
available to stable code anyway).
* The [`Div`] operator is implemented for [`Wrapping`] types.
* [`DerefMut` is implemented for `String`][dms].
* Performance of SipHash (the default hasher for `HashMap`) is
[better for long data][sh].
* [`AtomicPtr`] implements [`Send`].
* The [`read_to_end`] implementations for [`Stdin`] and [`File`]
are now [specialized to use uninitialized buffers for increased
performance][rte].
* Lifetime parameters of foreign functions [are now resolved
properly][f].
Misc
----
* Rust can now, with some coercion, [produce programs that run on
Windows XP][xp], though XP is not considered a supported platform.
* Porting Rust on Windows from the GNU toolchain to MSVC continues
([1][win1], [2][win2], [3][win3], [4][win4]). It is still not
recommended for use in 1.3, though should be fully-functional
in the [64-bit 1.4 beta][b14].
* On Fedora-based systems installation will [properly configure the
dynamic linker][fl].
* The compiler gained many new extended error descriptions, which can
be accessed with the `--explain` flag.
* The `dropck` pass, which checks that destructors can't access
destroyed values, [has been rewritten][dropck]. This fixes some
soundness holes, and as such will cause some previously-compiling
code to no longer build.
* `rustc` now uses [LLVM to write archive files where possible][ar].
Eventually this will eliminate the compiler's dependency on the ar
utility.
* Rust has [preliminary support for i686 FreeBSD][fb] (it has long
supported FreeBSD on x86_64).
* The [`unused_mut`][lum], [`unconditional_recursion`][lur],
[`improper_ctypes`][lic], and [`negate_unsigned`][lnu] lints are
more strict.
* If landing pads are disabled (with `-Z no-landing-pads`), [`panic!`
will kill the process instead of leaking][nlp].
[`Any`]: http://doc.rust-lang.org/nightly/std/any/trait.Any.html
[`AtomicPtr`]: http://doc.rust-lang.org/nightly/std/sync/atomic/struct.AtomicPtr.html
[`Borrow`]: http://doc.rust-lang.org/nightly/std/borrow/trait.Borrow.html
[`CStr`]: http://doc.rust-lang.org/nightly/std/ffi/struct.CStr.html
[`CString`]: http://doc.rust-lang.org/nightly/std/ffi/struct.CString.html
[`Debug`]: http://doc.rust-lang.org/nightly/std/fmt/trait.Debug.html
[`DerefMut`]: http://doc.rust-lang.org/nightly/std/ops/trait.DerefMut.html
[`Deref`]: http://doc.rust-lang.org/nightly/std/ops/trait.Deref.html
[`Div`]: http://doc.rust-lang.org/nightly/std/ops/trait.Div.html
[`Duration`]: http://doc.rust-lang.org/nightly/std/time/struct.Duration.html
[`Error`]: http://doc.rust-lang.org/nightly/std/error/trait.Error.html
[`File`]: http://doc.rust-lang.org/nightly/std/fs/struct.File.html
[`Hash`]: http://doc.rust-lang.org/nightly/std/hash/trait.Hash.html
[`Hasher`]: http://doc.rust-lang.org/nightly/std/hash/trait.Hasher.html
[`Send`]: http://doc.rust-lang.org/nightly/std/marker/trait.Send.html
[`SliceConcatExt`]: http://doc.rust-lang.org/nightly/std/slice/trait.SliceConcatExt.html
[`Stdin`]: http://doc.rust-lang.org/nightly/std/io/struct.Stdin.html
[`ToOwned`]: http://doc.rust-lang.org/nightly/std/borrow/trait.ToOwned.html
[`Wrapping`]: http://doc.rust-lang.org/nightly/std/num/struct.Wrapping.html
[`connect`]: http://doc.rust-lang.org/nightly/std/slice/trait.SliceConcatExt.html#method.connect
[`downcast_mut`]: http://doc.rust-lang.org/nightly/std/error/trait.Error.html#method.downcast_mut
[`downcast_ref`]: http://doc.rust-lang.org/nightly/std/error/trait.Error.html#method.downcast_ref
[`downcast`]: http://doc.rust-lang.org/nightly/std/error/trait.Error.html#method.downcast
[`hash_slice`]: http://doc.rust-lang.org/nightly/std/hash/trait.Hash.html#method.hash_slice
[`id`]: http://doc.rust-lang.org/nightly/std/process/struct.Child.html#method.id
[`is`]: http://doc.rust-lang.org/nightly/std/error/trait.Error.html#method.is
[`join`]: http://doc.rust-lang.org/nightly/std/slice/trait.SliceConcatExt.html#method.join
[`read_to_end`]: http://doc.rust-lang.org/nightly/std/io/trait.Read.html#method.read_to_end
[ar]: https://github.com/rust-lang/rust/pull/26926
[b14]: https://static.rust-lang.org/dist/rust-beta-x86_64-pc-windows-msvc.msi
[dms]: https://github.com/rust-lang/rust/pull/26241
[dropck]: https://github.com/rust-lang/rust/pull/27261
[dropckrfc]: https://github.com/rust-lang/rfcs/blob/master/text/0769-sound-generic-drop.md
[ds]: https://github.com/rust-lang/rust/pull/26818
[dst1]: http://doc.rust-lang.org/nightly/std/mem/fn.size_of_val.html
[dst2]: http://doc.rust-lang.org/nightly/std/mem/fn.align_of_val.html
[dst3]: https://github.com/rust-lang/rust/pull/27351
[e]: https://github.com/rust-lang/rust/pull/24793
[f]: https://github.com/rust-lang/rust/pull/26588
[fb]: https://github.com/rust-lang/rust/pull/26959
[fl]: https://github.com/rust-lang/rust-installer/pull/41
[hs]: http://doc.rust-lang.org/nightly/std/hash/trait.Hash.html#method.hash_slice
[ie]: http://doc.rust-lang.org/nightly/std/io/struct.Error.html
[iec]: http://doc.rust-lang.org/nightly/std/io/struct.Error.html#method.cause
[iegm]: http://doc.rust-lang.org/nightly/std/io/struct.Error.html#method.get_mut
[iegr]: http://doc.rust-lang.org/nightly/std/io/struct.Error.html#method.get_ref
[ieii]: http://doc.rust-lang.org/nightly/std/io/struct.Error.html#method.into_inner
[lic]: https://github.com/rust-lang/rust/pull/26583
[lnu]: https://github.com/rust-lang/rust/pull/27026
[lr]: https://github.com/rust-lang/rust/issues/27248
[lum]: https://github.com/rust-lang/rust/pull/26378
[lur]: https://github.com/rust-lang/rust/pull/26783
[nlp]: https://github.com/rust-lang/rust/pull/27176
[nold2]: https://github.com/rust-lang/rust/pull/27045
[nold]: https://github.com/rust-lang/rfcs/blob/master/text/1156-adjust-default-object-bounds.md
[nom]: http://doc.rust-lang.org/nightly/nomicon/
[pc]: http://doc.rust-lang.org/nightly/std/process/struct.Child.html
[pi]: https://github.com/rust-lang/rust/pull/26699
[ps]: https://github.com/rust-lang/rust/pull/26884
[rte]: https://github.com/rust-lang/rust/pull/26950
[sc]: http://doc.rust-lang.org/nightly/std/primitive.str.html#method.contains
[search]: https://github.com/rust-lang/rust/pull/26327
[sew]: http://doc.rust-lang.org/nightly/std/primitive.str.html#method.ends_with
[sf]: http://doc.rust-lang.org/nightly/std/primitive.str.html#method.find
[sh]: https://github.com/rust-lang/rust/pull/27280
[srf]: http://doc.rust-lang.org/nightly/std/primitive.str.html#method.rfind
[ss]: http://doc.rust-lang.org/nightly/std/primitive.str.html#method.split
[ssw]: http://doc.rust-lang.org/nightly/std/primitive.str.html#method.starts_with
[st]: https://github.com/rust-lang/rust/pull/26630
[win1]: https://github.com/rust-lang/rust/pull/26569
[win2]: https://github.com/rust-lang/rust/pull/26741
[win3]: https://github.com/rust-lang/rust/pull/26741
[win4]: https://github.com/rust-lang/rust/pull/27210
[xp]: https://github.com/rust-lang/rust/pull/26569
Version 1.2.0 (2015-08-07)
==========================
* ~1200 changes, numerous bugfixes
Highlights
----------
* [Dynamically-sized-type coercions][dst] allow smart pointer types
like `Rc` to contain types without a fixed size, arrays and trait
objects, finally enabling use of `Rc<[T]>` and completing the
implementation of DST.
* [Parallel codegen][parcodegen] is now working again, which can
substantially speed up large builds in debug mode; It also gets
another ~33% speedup when bootstrapping on a 4 core machine (using 8
jobs). It's not enabled by default, but will be "in the near
future". It can be activated with the `-C codegen-units=N` flag to
`rustc`.
* This is the first release with [experimental support for linking
with the MSVC linker and lib C on Windows (instead of using the GNU
variants via MinGW)][win]. It is yet recommended only for the most
intrepid Rustaceans.
* Benchmark compilations are showing a 30% improvement in
bootstrapping over 1.1.
Breaking Changes
----------------
* The [`to_uppercase`] and [`to_lowercase`] methods on `char` now do
unicode case mapping, which is a previously-planned change in
behavior and considered a bugfix.
* [`mem::align_of`] now specifies [the *minimum alignment* for
T][align], which is usually the alignment programs are interested
in, and the same value reported by clang's
`alignof`. [`mem::min_align_of`] is deprecated. This is not known to
break real code.
* [The `#[packed]` attribute is no longer silently accepted by the
compiler][packed]. This attribute did nothing and code that
mentioned it likely did not work as intended.
* Associated type defaults are [now behind the
`associated_type_defaults` feature gate][ad]. In 1.1 associated type
defaults *did not work*, but could be mentioned syntactically. As
such this breakage has minimal impact.
Language
--------
* Patterns with `ref mut` now correctly invoke [`DerefMut`] when
matching against dereferencable values.
Libraries
---------
* The [`Extend`] trait, which grows a collection from an iterator, is
implemented over iterators of references, for `String`, `Vec`,
`LinkedList`, `VecDeque`, `EnumSet`, `BinaryHeap`, `VecMap`,
`BTreeSet` and `BTreeMap`. [RFC][extend-rfc].
* The [`iter::once`] function returns an iterator that yields a single
element, and [`iter::empty`] returns an iterator that yields no
elements.
* The [`matches`] and [`rmatches`] methods on `str` return iterators
over substring matches.
* [`Cell`] and [`RefCell`] both implement `Eq`.
* A number of methods for wrapping arithmetic are added to the
integral types, [`wrapping_div`], [`wrapping_rem`],
[`wrapping_neg`], [`wrapping_shl`], [`wrapping_shr`]. These are in
addition to the existing [`wrapping_add`], [`wrapping_sub`], and
[`wrapping_mul`] methods, and alternatives to the [`Wrapping`]
type.. It is illegal for the default arithmetic operations in Rust
to overflow; the desire to wrap must be explicit.
* The `{:#?}` formatting specifier [displays the alternate,
pretty-printed][debugfmt] form of the `Debug` formatter. This
feature was actually introduced prior to 1.0 with little
fanfare.
* [`fmt::Formatter`] implements [`fmt::Write`], a `fmt`-specific trait
for writing data to formatted strings, similar to [`io::Write`].
* [`fmt::Formatter`] adds 'debug builder' methods, [`debug_struct`],
[`debug_tuple`], [`debug_list`], [`debug_set`], [`debug_map`]. These
are used by code generators to emit implementations of [`Debug`].
* `str` has new [`to_uppercase`][strup] and [`to_lowercase`][strlow]
methods that convert case, following Unicode case mapping.
* It is now easier to handle poisoned locks. The [`PoisonError`]
type, returned by failing lock operations, exposes `into_inner`,
`get_ref`, and `get_mut`, which all give access to the inner lock
guard, and allow the poisoned lock to continue to operate. The
`is_poisoned` method of [`RwLock`] and [`Mutex`] can poll for a
poisoned lock without attempting to take the lock.
* On Unix the [`FromRawFd`] trait is implemented for [`Stdio`], and
[`AsRawFd`] for [`ChildStdin`], [`ChildStdout`], [`ChildStderr`].
On Windows the `FromRawHandle` trait is implemented for `Stdio`,
and `AsRawHandle` for `ChildStdin`, `ChildStdout`,
`ChildStderr`.
* [`io::ErrorKind`] has a new variant, `InvalidData`, which indicates
malformed input.
Misc
----
* `rustc` employs smarter heuristics for guessing at [typos].
* `rustc` emits more efficient code for [no-op conversions between
unsafe pointers][nop].
* Fat pointers are now [passed in pairs of immediate arguments][fat],
resulting in faster compile times and smaller code.
[`Extend`]: https://doc.rust-lang.org/nightly/std/iter/trait.Extend.html
[extend-rfc]: https://github.com/rust-lang/rfcs/blob/master/text/0839-embrace-extend-extinguish.md
[`iter::once`]: https://doc.rust-lang.org/nightly/std/iter/fn.once.html
[`iter::empty`]: https://doc.rust-lang.org/nightly/std/iter/fn.empty.html
[`matches`]: https://doc.rust-lang.org/nightly/std/primitive.str.html#method.matches
[`rmatches`]: https://doc.rust-lang.org/nightly/std/primitive.str.html#method.rmatches
[`Cell`]: https://doc.rust-lang.org/nightly/std/cell/struct.Cell.html
[`RefCell`]: https://doc.rust-lang.org/nightly/std/cell/struct.RefCell.html
[`wrapping_add`]: https://doc.rust-lang.org/nightly/std/primitive.i8.html#method.wrapping_add
[`wrapping_sub`]: https://doc.rust-lang.org/nightly/std/primitive.i8.html#method.wrapping_sub
[`wrapping_mul`]: https://doc.rust-lang.org/nightly/std/primitive.i8.html#method.wrapping_mul
[`wrapping_div`]: https://doc.rust-lang.org/nightly/std/primitive.i8.html#method.wrapping_div
[`wrapping_rem`]: https://doc.rust-lang.org/nightly/std/primitive.i8.html#method.wrapping_rem
[`wrapping_neg`]: https://doc.rust-lang.org/nightly/std/primitive.i8.html#method.wrapping_neg
[`wrapping_shl`]: https://doc.rust-lang.org/nightly/std/primitive.i8.html#method.wrapping_shl
[`wrapping_shr`]: https://doc.rust-lang.org/nightly/std/primitive.i8.html#method.wrapping_shr
[`Wrapping`]: https://doc.rust-lang.org/nightly/std/num/struct.Wrapping.html
[`fmt::Formatter`]: https://doc.rust-lang.org/nightly/std/fmt/struct.Formatter.html
[`fmt::Write`]: https://doc.rust-lang.org/nightly/std/fmt/trait.Write.html
[`io::Write`]: https://doc.rust-lang.org/nightly/std/io/trait.Write.html
[`debug_struct`]: https://doc.rust-lang.org/nightly/core/fmt/struct.Formatter.html#method.debug_struct
[`debug_tuple`]: https://doc.rust-lang.org/nightly/core/fmt/struct.Formatter.html#method.debug_tuple
[`debug_list`]: https://doc.rust-lang.org/nightly/core/fmt/struct.Formatter.html#method.debug_list
[`debug_set`]: https://doc.rust-lang.org/nightly/core/fmt/struct.Formatter.html#method.debug_set
[`debug_map`]: https://doc.rust-lang.org/nightly/core/fmt/struct.Formatter.html#method.debug_map
[`Debug`]: https://doc.rust-lang.org/nightly/std/fmt/trait.Debug.html
[strup]: https://doc.rust-lang.org/nightly/std/primitive.str.html#method.to_uppercase
[strlow]: https://doc.rust-lang.org/nightly/std/primitive.str.html#method.to_lowercase
[`to_uppercase`]: https://doc.rust-lang.org/nightly/std/primitive.char.html#method.to_uppercase
[`to_lowercase`]: https://doc.rust-lang.org/nightly/std/primitive.char.html#method.to_lowercase
[`PoisonError`]: https://doc.rust-lang.org/nightly/std/sync/struct.PoisonError.html
[`RwLock`]: https://doc.rust-lang.org/nightly/std/sync/struct.RwLock.html
[`Mutex`]: https://doc.rust-lang.org/nightly/std/sync/struct.Mutex.html
[`FromRawFd`]: https://doc.rust-lang.org/nightly/std/os/unix/io/trait.FromRawFd.html
[`AsRawFd`]: https://doc.rust-lang.org/nightly/std/os/unix/io/trait.AsRawFd.html
[`Stdio`]: https://doc.rust-lang.org/nightly/std/process/struct.Stdio.html
[`ChildStdin`]: https://doc.rust-lang.org/nightly/std/process/struct.ChildStdin.html
[`ChildStdout`]: https://doc.rust-lang.org/nightly/std/process/struct.ChildStdout.html
[`ChildStderr`]: https://doc.rust-lang.org/nightly/std/process/struct.ChildStderr.html
[`io::ErrorKind`]: https://doc.rust-lang.org/nightly/std/io/enum.ErrorKind.html
[debugfmt]: https://www.reddit.com/r/rust/comments/3ceaui/psa_produces_prettyprinted_debug_output/
[`DerefMut`]: https://doc.rust-lang.org/nightly/std/ops/trait.DerefMut.html
[`mem::align_of`]: https://doc.rust-lang.org/nightly/std/mem/fn.align_of.html
[align]: https://github.com/rust-lang/rust/pull/25646
[`mem::min_align_of`]: https://doc.rust-lang.org/nightly/std/mem/fn.min_align_of.html
[typos]: https://github.com/rust-lang/rust/pull/26087
[nop]: https://github.com/rust-lang/rust/pull/26336
[fat]: https://github.com/rust-lang/rust/pull/26411
[dst]: https://github.com/rust-lang/rfcs/blob/master/text/0982-dst-coercion.md
[parcodegen]: https://github.com/rust-lang/rust/pull/26018
[packed]: https://github.com/rust-lang/rust/pull/25541
[ad]: https://github.com/rust-lang/rust/pull/27382
[win]: https://github.com/rust-lang/rust/pull/25350
Version 1.1.0 (2015-06-25)
=========================
* ~850 changes, numerous bugfixes
Highlights
----------
* The [`std::fs` module has been expanded][fs] to expand the set of
functionality exposed:
* `DirEntry` now supports optimizations like `file_type` and `metadata` which
don't incur a syscall on some platforms.
* A `symlink_metadata` function has been added.
* The `fs::Metadata` structure now lowers to its OS counterpart, providing
access to all underlying information.
* The compiler now contains extended explanations of many errors. When an error
with an explanation occurs the compiler suggests using the `--explain` flag
to read the explanation. Error explanations are also [available online][err-index].
* Thanks to multiple [improvements][sk] to [type checking][pre], as
well as other work, the time to bootstrap the compiler decreased by
32%.
Libraries
---------
* The [`str::split_whitespace`] method splits a string on unicode
whitespace boundaries.
* On both Windows and Unix, new extension traits provide conversion of
I/O types to and from the underlying system handles. On Unix, these
traits are [`FromRawFd`] and [`AsRawFd`], on Windows `FromRawHandle`
and `AsRawHandle`. These are implemented for `File`, `TcpStream`,
`TcpListener`, and `UpdSocket`. Further implementations for
`std::process` will be stabilized later.
* On Unix, [`std::os::unix::symlink`] creates symlinks. On
Windows, symlinks can be created with
`std::os::windows::symlink_dir` and
`std::os::windows::symlink_file`.
* The `mpsc::Receiver` type can now be converted into an iterator with
`into_iter` on the [`IntoIterator`] trait.
* `Ipv4Addr` can be created from `u32` with the `From<u32>`
implementation of the [`From`] trait.
* The `Debug` implementation for `RangeFull` [creates output that is
more consistent with other implementations][rf].
* [`Debug` is implemented for `File`][file].
* The `Default` implementation for `Arc` [no longer requires `Sync +
Send`][arc].
* [The `Iterator` methods `count`, `nth`, and `last` have been
overridden for slices to have O(1) performance instead of O(n)][si].
* Incorrect handling of paths on Windows has been improved in both the
compiler and the standard library.
* [`AtomicPtr` gained a `Default` implementation][ap].
* In accordance with Rust's policy on arithmetic overflow `abs` now
[panics on overflow when debug assertions are enabled][abs].
* The [`Cloned`] iterator, which was accidentally left unstable for
1.0 [has been stabilized][c].
* The [`Incoming`] iterator, which iterates over incoming TCP
connections, and which was accidentally unnamable in 1.0, [is now
properly exported][inc].
* [`BinaryHeap`] no longer corrupts itself [when functions called by
`sift_up` or `sift_down` panic][bh].
* The [`split_off`] method of `LinkedList` [no longer corrupts
the list in certain scenarios][ll].
Misc
----
* Type checking performance [has improved notably][sk] with
[multiple improvements][pre].
* The compiler [suggests code changes][ch] for more errors.
* rustc and it's build system have experimental support for [building
toolchains against MUSL][m] instead of glibc on Linux.
* The compiler defines the `target_env` cfg value, which is used for
distinguishing toolchains that are otherwise for the same
platform. Presently this is set to `gnu` for common GNU Linux
targets and for MinGW targets, and `musl` for MUSL Linux targets.
* The [`cargo rustc`][crc] command invokes a build with custom flags
to rustc.
* [Android executables are always position independent][pie].
* [The `drop_with_repr_extern` lint warns about mixing `repr(C)`
with `Drop`][drop].
[`str::split_whitespace`]: https://doc.rust-lang.org/nightly/std/primitive.str.html#method.split_whitespace
[`FromRawFd`]: https://doc.rust-lang.org/nightly/std/os/unix/io/trait.FromRawFd.html
[`AsRawFd`]: https://doc.rust-lang.org/nightly/std/os/unix/io/trait.AsRawFd.html
[`std::os::unix::symlink`]: https://doc.rust-lang.org/nightly/std/os/unix/fs/fn.symlink.html
[`IntoIterator`]: https://doc.rust-lang.org/nightly/std/iter/trait.IntoIterator.html
[`From`]: https://doc.rust-lang.org/nightly/std/convert/trait.From.html
[rf]: https://github.com/rust-lang/rust/pull/24491
[err-index]: https://doc.rust-lang.org/error-index.html
[sk]: https://github.com/rust-lang/rust/pull/24615
[pre]: https://github.com/rust-lang/rust/pull/25323
[file]: https://github.com/rust-lang/rust/pull/24598
[ch]: https://github.com/rust-lang/rust/pull/24683
[arc]: https://github.com/rust-lang/rust/pull/24695
[si]: https://github.com/rust-lang/rust/pull/24701
[ap]: https://github.com/rust-lang/rust/pull/24834
[m]: https://github.com/rust-lang/rust/pull/24777
[fs]: https://github.com/rust-lang/rfcs/blob/master/text/1044-io-fs-2.1.md
[crc]: https://github.com/rust-lang/cargo/pull/1568
[pie]: https://github.com/rust-lang/rust/pull/24953
[abs]: https://github.com/rust-lang/rust/pull/25441
[c]: https://github.com/rust-lang/rust/pull/25496
[`Cloned`]: https://doc.rust-lang.org/nightly/std/iter/struct.Cloned.html
[`Incoming`]: https://doc.rust-lang.org/nightly/std/net/struct.Incoming.html
[inc]: https://github.com/rust-lang/rust/pull/25522
[bh]: https://github.com/rust-lang/rust/pull/25856
[`BinaryHeap`]: https://doc.rust-lang.org/nightly/std/collections/struct.BinaryHeap.html
[ll]: https://github.com/rust-lang/rust/pull/26022
[`split_off`]: https://doc.rust-lang.org/nightly/collections/linked_list/struct.LinkedList.html#method.split_off
[drop]: https://github.com/rust-lang/rust/pull/24935
Version 1.0.0 (2015-05-15)
========================
* ~1500 changes, numerous bugfixes
Highlights
----------
* The vast majority of the standard library is now `#[stable]`. It is
no longer possible to use unstable features with a stable build of
the compiler.
* Many popular crates on [crates.io] now work on the stable release
channel.
* Arithmetic on basic integer types now [checks for overflow in debug
builds][overflow].
Language
--------
* Several [restrictions have been added to trait coherence][coh] in
order to make it easier for upstream authors to change traits
without breaking downstream code.
* Digits of binary and octal literals are [lexed more eagerly][lex] to
improve error messages and macro behavior. For example, `0b1234` is
now lexed as `0b1234` instead of two tokens, `0b1` and `234`.
* Trait bounds [are always invariant][inv], eliminating the need for
the `PhantomFn` and `MarkerTrait` lang items, which have been
removed.
* ["-" is no longer a valid character in crate names][cr], the `extern crate
"foo" as bar` syntax has been replaced with `extern crate foo as
bar`, and Cargo now automatically translates "-" in *package* names
to underscore for the crate name.
* [Lifetime shadowing is an error][lt].
* [`Send` no longer implies `'static`][send-rfc].
* [UFCS now supports trait-less associated paths][moar-ufcs] like
`MyType::default()`.
* Primitive types [now have inherent methods][prim-inherent],
obviating the need for extension traits like `SliceExt`.
* Methods with `Self: Sized` in their `where` clause are [considered
object-safe][self-sized], allowing many extension traits like
`IteratorExt` to be merged into the traits they extended.
* You can now [refer to associated types][assoc-where] whose
corresponding trait bounds appear only in a `where` clause.
* The final bits of [OIBIT landed][oibit-final], meaning that traits
like `Send` and `Sync` are now library-defined.
* A [Reflect trait][reflect] was introduced, which means that
downcasting via the `Any` trait is effectively limited to concrete
types. This helps retain the potentially-important "parametricity"
property: generic code cannot behave differently for different type
arguments except in minor ways.
* The `unsafe_destructor` feature is now deprecated in favor of the
[new `dropck`][dropck]. This change is a major reduction in unsafe
code.
Libraries
---------
* The `thread_local` module [has been renamed to `std::thread`][th].
* The methods of `IteratorExt` [have been moved to the `Iterator`
trait itself][ie].
* Several traits that implement Rust's conventions for type
conversions, `AsMut`, `AsRef`, `From`, and `Into` have been
[centralized in the `std::convert` module][con].
* The `FromError` trait [was removed in favor of `From`][fe].
* The basic sleep function [has moved to
`std::thread::sleep_ms`][slp].
* The `splitn` function now takes an `n` parameter that represents the
number of items yielded by the returned iterator [instead of the
number of 'splits'][spl].
* [On Unix, all file descriptors are `CLOEXEC` by default][clo].
* [Derived implementations of `PartialOrd` now order enums according
to their explicitly-assigned discriminants][po].
* [Methods for searching strings are generic over `Pattern`s][pat],
implemented presently by `&char`, `&str`, `FnMut(char) -> bool` and
some others.
* [In method resolution, object methods are resolved before inherent
methods][meth].
* [`String::from_str` has been deprecated in favor of the `From` impl,
`String::from`][sf].
* [`io::Error` implements `Sync`][ios].
* [The `words` method on `&str` has been replaced with
`split_whitespace`][sw], to avoid answering the tricky question, 'what is
a word?'
* The new path and IO modules are complete and `#[stable]`. This
was the major library focus for this cycle.
* The path API was [revised][path-normalize] to normalize `.`,
adjusting the tradeoffs in favor of the most common usage.
* A large number of remaining APIs in `std` were also stabilized
during this cycle; about 75% of the non-deprecated API surface
is now stable.
* The new [string pattern API][string-pattern] landed, which makes
the string slice API much more internally consistent and flexible.
* A new set of [generic conversion traits][conversion] replaced
many existing ad hoc traits.
* Generic numeric traits were [completely removed][num-traits]. This
was made possible thanks to inherent methods for primitive types,
and the removal gives maximal flexibility for designing a numeric
hierarchy in the future.
* The `Fn` traits are now related via [inheritance][fn-inherit]
and provide ergonomic [blanket implementations][fn-blanket].
* The `Index` and `IndexMut` traits were changed to
[take the index by value][index-value], enabling code like
`hash_map["string"]` to work.
* `Copy` now [inherits][copy-clone] from `Clone`, meaning that all
`Copy` data is known to be `Clone` as well.
Misc
----
* Many errors now have extended explanations that can be accessed with
the `--explain` flag to `rustc`.
* Many new examples have been added to the standard library
documentation.
* rustdoc has received a number of improvements focused on completion
and polish.
* Metadata was tuned, shrinking binaries [by 27%][metadata-shrink].
* Much headway was made on ecosystem-wide CI, making it possible
to [compare builds for breakage][ci-compare].
[crates.io]: http://crates.io
[clo]: https://github.com/rust-lang/rust/pull/24034
[coh]: https://github.com/rust-lang/rfcs/blob/master/text/1023-rebalancing-coherence.md
[con]: https://github.com/rust-lang/rust/pull/23875
[cr]: https://github.com/rust-lang/rust/pull/23419
[fe]: https://github.com/rust-lang/rust/pull/23879
[ie]: https://github.com/rust-lang/rust/pull/23300
[inv]: https://github.com/rust-lang/rust/pull/23938
[ios]: https://github.com/rust-lang/rust/pull/24133
[lex]: https://github.com/rust-lang/rfcs/blob/master/text/0879-small-base-lexing.md
[lt]: https://github.com/rust-lang/rust/pull/24057
[meth]: https://github.com/rust-lang/rust/pull/24056
[pat]: https://github.com/rust-lang/rfcs/blob/master/text/0528-string-patterns.md
[po]: https://github.com/rust-lang/rust/pull/24270
[sf]: https://github.com/rust-lang/rust/pull/24517
[slp]: https://github.com/rust-lang/rust/pull/23949
[spl]: https://github.com/rust-lang/rfcs/blob/master/text/0979-align-splitn-with-other-languages.md
[sw]: https://github.com/rust-lang/rfcs/blob/master/text/1054-str-words.md
[th]: https://github.com/rust-lang/rfcs/blob/master/text/0909-move-thread-local-to-std-thread.md
[send-rfc]: https://github.com/rust-lang/rfcs/blob/master/text/0458-send-improvements.md
[moar-ufcs]: https://github.com/rust-lang/rust/pull/22172
[prim-inherent]: https://github.com/rust-lang/rust/pull/23104
[overflow]: https://github.com/rust-lang/rfcs/blob/master/text/0560-integer-overflow.md
[metadata-shrink]: https://github.com/rust-lang/rust/pull/22971
[self-sized]: https://github.com/rust-lang/rust/pull/22301
[assoc-where]: https://github.com/rust-lang/rust/pull/22512
[string-pattern]: https://github.com/rust-lang/rust/pull/22466
[oibit-final]: https://github.com/rust-lang/rust/pull/21689
[reflect]: https://github.com/rust-lang/rust/pull/23712
[conversion]: https://github.com/rust-lang/rfcs/pull/529
[num-traits]: https://github.com/rust-lang/rust/pull/23549
[index-value]: https://github.com/rust-lang/rust/pull/23601
[dropck]: https://github.com/rust-lang/rfcs/pull/769
[ci-compare]: https://gist.github.com/brson/a30a77836fbec057cbee
[fn-inherit]: https://github.com/rust-lang/rust/pull/23282
[fn-blanket]: https://github.com/rust-lang/rust/pull/23895
[copy-clone]: https://github.com/rust-lang/rust/pull/23860
[path-normalize]: https://github.com/rust-lang/rust/pull/23229
Version 1.0.0-alpha.2 (2015-02-20)
=====================================
* ~1300 changes, numerous bugfixes
* Highlights
* The various I/O modules were [overhauled][io-rfc] to reduce
unnecessary abstractions and provide better interoperation with
the underlying platform. The old `io` module remains temporarily
at `std::old_io`.
* The standard library now [participates in feature gating][feat],
so use of unstable libraries now requires a `#![feature(...)]`
attribute. The impact of this change is [described on the
forum][feat-forum]. [RFC][feat-rfc].
* Language
* `for` loops [now operate on the `IntoIterator` trait][into],
which eliminates the need to call `.iter()`, etc. to iterate
over collections. There are some new subtleties to remember
though regarding what sort of iterators various types yield, in
particular that `for foo in bar { }` yields values from a move
iterator, destroying the original collection. [RFC][into-rfc].
* Objects now have [default lifetime bounds][obj], so you don't
have to write `Box<Trait+'static>` when you don't care about
storing references. [RFC][obj-rfc].
* In types that implement `Drop`, [lifetimes must outlive the
value][drop]. This will soon make it possible to safely
implement `Drop` for types where `#[unsafe_destructor]` is now
required. Read the [gorgeous RFC][drop-rfc] for details.
* The fully qualified <T as Trait>::X syntax lets you set the Self
type for a trait method or associated type. [RFC][ufcs-rfc].
* References to types that implement `Deref<U>` now [automatically
coerce to references][deref] to the dereferenced type `U`,
e.g. `&T where T: Deref<U>` automatically coerces to `&U`. This
should eliminate many unsightly uses of `&*`, as when converting
from references to vectors into references to
slices. [RFC][deref-rfc].
* The explicit [closure kind syntax][close] (`|&:|`, `|&mut:|`,
`|:|`) is obsolete and closure kind is inferred from context.
* [`Self` is a keyword][Self].
* Libraries
* The `Show` and `String` formatting traits [have been
renamed][fmt] to `Debug` and `Display` to more clearly reflect
their related purposes. Automatically getting a string
conversion to use with `format!("{:?}", something_to_debug)` is
now written `#[derive(Debug)]`.
* Abstract [OS-specific string types][osstr], `std::ff::{OsString,
OsStr}`, provide strings in platform-specific encodings for easier
interop with system APIs. [RFC][osstr-rfc].
* The `boxed::into_raw` and `Box::from_raw` functions [convert
between `Box<T>` and `*mut T`][boxraw], a common pattern for
creating raw pointers.
* Tooling
* Certain long error messages of the form 'expected foo found bar'
are now [split neatly across multiple
lines][multiline]. Examples in the PR.
* On Unix Rust can be [uninstalled][un] by running
`/usr/local/lib/rustlib/uninstall.sh`.
* The `#[rustc_on_unimplemented]` attribute, requiring the
'on_unimplemented' feature, lets rustc [display custom error
messages when a trait is expected to be implemented for a type
but is not][onun].
* Misc
* Rust is tested against a [LALR grammar][lalr], which parses
almost all the Rust files that rustc does.
[boxraw]: https://github.com/rust-lang/rust/pull/21318
[close]: https://github.com/rust-lang/rust/pull/21843
[deref]: https://github.com/rust-lang/rust/pull/21351
[deref-rfc]: https://github.com/rust-lang/rfcs/blob/master/text/0241-deref-conversions.md
[drop]: https://github.com/rust-lang/rust/pull/21972
[drop-rfc]: https://github.com/rust-lang/rfcs/blob/master/text/0769-sound-generic-drop.md
[feat]: https://github.com/rust-lang/rust/pull/21248
[feat-forum]: https://users.rust-lang.org/t/psa-important-info-about-rustcs-new-feature-staging/82/5
[feat-rfc]: https://github.com/rust-lang/rfcs/blob/master/text/0507-release-channels.md
[fmt]: https://github.com/rust-lang/rust/pull/21457
[into]: https://github.com/rust-lang/rust/pull/20790
[into-rfc]: https://github.com/rust-lang/rfcs/blob/master/text/0235-collections-conventions.md#intoiterator-and-iterable
[io-rfc]: https://github.com/rust-lang/rfcs/blob/master/text/0517-io-os-reform.md
[lalr]: https://github.com/rust-lang/rust/pull/21452
[multiline]: https://github.com/rust-lang/rust/pull/19870
[obj]: https://github.com/rust-lang/rust/pull/22230
[obj-rfc]: https://github.com/rust-lang/rfcs/blob/master/text/0599-default-object-bound.md
[onun]: https://github.com/rust-lang/rust/pull/20889
[osstr]: https://github.com/rust-lang/rust/pull/21488
[osstr-rfc]: https://github.com/rust-lang/rfcs/blob/master/text/0517-io-os-reform.md
[Self]: https://github.com/rust-lang/rust/pull/22158
[ufcs-rfc]: https://github.com/rust-lang/rfcs/blob/master/text/0132-ufcs.md
[un]: https://github.com/rust-lang/rust/pull/22256
Version 1.0.0-alpha (2015-01-09)
==================================
* ~2400 changes, numerous bugfixes
* Highlights
* The language itself is considered feature complete for 1.0,
though there will be many usability improvements and bugfixes
before the final release.
* Nearly 50% of the public API surface of the standard library has
been declared 'stable'. Those interfaces are unlikely to change
before 1.0.
* The long-running debate over integer types has been
[settled][ints]: Rust will ship with types named `isize` and
`usize`, rather than `int` and `uint`, for pointer-sized
integers. Guidelines will be rolled out during the alpha cycle.
* Most crates that are not `std` have been moved out of the Rust
distribution into the Cargo ecosystem so they can evolve
separately and don't need to be stabilized as quickly, including
'time', 'getopts', 'num', 'regex', and 'term'.
* Documentation continues to be expanded with more API coverage, more
examples, and more in-depth explanations. The guides have been
consolidated into [The Rust Programming Language][trpl].
* "[Rust By Example][rbe]" is now maintained by the Rust team.
* All official Rust binary installers now come with [Cargo], the
Rust package manager.
* Language
* Closures have been [completely redesigned][unboxed] to be
implemented in terms of traits, can now be used as generic type
bounds and thus monomorphized and inlined, or via an opaque
pointer (boxed) as in the old system. The new system is often
referred to as 'unboxed' closures.
* Traits now support [associated types][assoc], allowing families
of related types to be defined together and used generically in
powerful ways.
* Enum variants are [namespaced by their type names][enum].
* [`where` clauses][where] provide a more versatile and attractive
syntax for specifying generic bounds, though the previous syntax
remains valid.
* Rust again picks a [fallback][fb] (either i32 or f64) for uninferred
numeric types.
* Rust [no longer has a runtime][rt] of any description, and only
supports OS threads, not green threads.
* At long last, Rust has been overhauled for 'dynamically-sized
types' ([DST]), which integrates 'fat pointers' (object types,
arrays, and `str`) more deeply into the type system, making it
more consistent.
* Rust now has a general [range syntax][range], `i..j`, `i..`, and
`..j` that produce range types and which, when combined with the
`Index` operator and multidispatch, leads to a convenient slice
notation, `[i..j]`.
* The new range syntax revealed an ambiguity in the fixed-length
array syntax, so now fixed length arrays [are written `[T;
N]`][arrays].
* The `Copy` trait is no longer implemented automatically. Unsafe
pointers no longer implement `Sync` and `Send` so types
containing them don't automatically either. `Sync` and `Send`
are now 'unsafe traits' so one can "forcibly" implement them via
`unsafe impl` if a type confirms to the requirements for them
even though the internals do not (e.g. structs containing unsafe
pointers like `Arc`). These changes are intended to prevent some
footguns and are collectively known as [opt-in built-in
traits][oibit] (though `Sync` and `Send` will soon become pure
library types unknown to the compiler).
* Operator traits now take their operands [by value][ops], and
comparison traits can use multidispatch to compare one type
against multiple other types, allowing e.g. `String` to be
compared with `&str`.
* `if let` and `while let` are no longer feature-gated.
* Rust has adopted a more [uniform syntax for escaping unicode
characters][unicode].
* `macro_rules!` [has been declared stable][mac]. Though it is a
flawed system it is sufficiently popular that it must be usable
for 1.0. Effort has gone into [future-proofing][mac-future] it
in ways that will allow other macro systems to be developed in
parallel, and won't otherwise impact the evolution of the
language.
* The prelude has been [pared back significantly][prelude] such
that it is the minimum necessary to support the most pervasive
code patterns, and through [generalized where clauses][where]
many of the prelude extension traits have been consolidated.
* Rust's rudimentary reflection [has been removed][refl], as it
incurred too much code generation for little benefit.
* [Struct variants][structvars] are no longer feature-gated.
* Trait bounds can be [polymorphic over lifetimes][hrtb]. Also
known as 'higher-ranked trait bounds', this crucially allows
unboxed closures to work.
* Macros invocations surrounded by parens or square brackets and
not terminated by a semicolon are [parsed as
expressions][macros], which makes expressions like `vec![1i32,
2, 3].len()` work as expected.
* Trait objects now implement their traits automatically, and
traits that can be coerced to objects now must be [object
safe][objsafe].
* Automatically deriving traits is now done with `#[derive(...)]`
not `#[deriving(...)]` for [consistency with other naming
conventions][derive].
* Importing the containing module or enum at the same time as
items or variants they contain is [now done with `self` instead
of `mod`][self], as in use `foo::{self, bar}`
* Glob imports are no longer feature-gated.
* The `box` operator and `box` patterns have been feature-gated
pending a redesign. For now unique boxes should be allocated
like other containers, with `Box::new`.
* Libraries
* A [series][coll1] of [efforts][coll2] to establish
[conventions][coll3] for collections types has resulted in API
improvements throughout the standard library.
* New [APIs for error handling][err] provide ergonomic interop
between error types, and [new conventions][err-conv] describe
more clearly the recommended error handling strategies in Rust.
* The `fail!` macro has been renamed to [`panic!`][panic] so that
it is easier to discuss failure in the context of error handling
without making clarifications as to whether you are referring to
the 'fail' macro or failure more generally.
* On Linux, `OsRng` prefers the new, more reliable `getrandom`
syscall when available.
* The 'serialize' crate has been renamed 'rustc-serialize' and
moved out of the distribution to Cargo. Although it is widely
used now, it is expected to be superseded in the near future.
* The `Show` formatter, typically implemented with
`#[derive(Show)]` is [now requested with the `{:?}`
specifier][show] and is intended for use by all types, for uses
such as `println!` debugging. The new `String` formatter must be
implemented by hand, uses the `{}` specifier, and is intended
for full-fidelity conversions of things that can logically be
represented as strings.
* Tooling
* [Flexible target specification][flex] allows rustc's code
generation to be configured to support otherwise-unsupported
platforms.
* Rust comes with rust-gdb and rust-lldb scripts that launch their
respective debuggers with Rust-appropriate pretty-printing.
* The Windows installation of Rust is distributed with the
MinGW components currently required to link binaries on that
platform.
* Misc
* Nullable enum optimizations have been extended to more types so
that e.g. `Option<Vec<T>>` and `Option<String>` take up no more
space than the inner types themselves.
* Work has begun on supporting AArch64.
[Cargo]: https://crates.io
[unboxed]: http://smallcultfollowing.com/babysteps/blog/2014/11/26/purging-proc/
[enum]: https://github.com/rust-lang/rfcs/blob/master/text/0390-enum-namespacing.md
[flex]: https://github.com/rust-lang/rfcs/blob/master/text/0131-target-specification.md
[err]: https://github.com/rust-lang/rfcs/blob/master/text/0201-error-chaining.md
[err-conv]: https://github.com/rust-lang/rfcs/blob/master/text/0236-error-conventions.md
[rt]: https://github.com/rust-lang/rfcs/blob/master/text/0230-remove-runtime.md
[mac]: https://github.com/rust-lang/rfcs/blob/master/text/0453-macro-reform.md
[mac-future]: https://github.com/rust-lang/rfcs/pull/550
[DST]: http://smallcultfollowing.com/babysteps/blog/2014/01/05/dst-take-5/
[coll1]: https://github.com/rust-lang/rfcs/blob/master/text/0235-collections-conventions.md
[coll2]: https://github.com/rust-lang/rfcs/blob/master/text/0509-collections-reform-part-2.md
[coll3]: https://github.com/rust-lang/rfcs/blob/master/text/0216-collection-views.md
[ops]: https://github.com/rust-lang/rfcs/blob/master/text/0439-cmp-ops-reform.md
[prelude]: https://github.com/rust-lang/rfcs/blob/master/text/0503-prelude-stabilization.md
[where]: https://github.com/rust-lang/rfcs/blob/master/text/0135-where.md
[refl]: https://github.com/rust-lang/rfcs/blob/master/text/0379-remove-reflection.md
[panic]: https://github.com/rust-lang/rfcs/blob/master/text/0221-panic.md
[structvars]: https://github.com/rust-lang/rfcs/blob/master/text/0418-struct-variants.md
[hrtb]: https://github.com/rust-lang/rfcs/blob/master/text/0387-higher-ranked-trait-bounds.md
[unicode]: https://github.com/rust-lang/rfcs/blob/master/text/0446-es6-unicode-escapes.md
[oibit]: https://github.com/rust-lang/rfcs/blob/master/text/0019-opt-in-builtin-traits.md
[macros]: https://github.com/rust-lang/rfcs/blob/master/text/0378-expr-macros.md
[range]: https://github.com/rust-lang/rfcs/blob/master/text/0439-cmp-ops-reform.md#indexing-and-slicing
[arrays]: https://github.com/rust-lang/rfcs/blob/master/text/0520-new-array-repeat-syntax.md
[show]: https://github.com/rust-lang/rfcs/blob/master/text/0504-show-stabilization.md
[derive]: https://github.com/rust-lang/rfcs/blob/master/text/0534-deriving2derive.md
[self]: https://github.com/rust-lang/rfcs/blob/master/text/0532-self-in-use.md
[fb]: https://github.com/rust-lang/rfcs/blob/master/text/0212-restore-int-fallback.md
[objsafe]: https://github.com/rust-lang/rfcs/blob/master/text/0255-object-safety.md
[assoc]: https://github.com/rust-lang/rfcs/blob/master/text/0195-associated-items.md
[ints]: https://github.com/rust-lang/rfcs/pull/544#issuecomment-68760871
[trpl]: https://doc.rust-lang.org/book/index.html
[rbe]: http://rustbyexample.com/
Version 0.12.0 (2014-10-09)
=============================
* ~1900 changes, numerous bugfixes
* Highlights
* The introductory documentation (now called The Rust Guide) has
been completely rewritten, as have a number of supplementary
guides.
* Rust's package manager, Cargo, continues to improve and is
sometimes considered to be quite awesome.
* Many API's in `std` have been reviewed and updated for
consistency with the in-development Rust coding
guidelines. The standard library documentation tracks
stabilization progress.
* Minor libraries have been moved out-of-tree to the rust-lang org
on GitHub: uuid, semver, glob, num, hexfloat, fourcc. They can
be installed with Cargo.
* Lifetime elision allows lifetime annotations to be left off of
function declarations in many common scenarios.
* Rust now works on 64-bit Windows.
* Language
* Indexing can be overloaded with the `Index` and `IndexMut`
traits.
* The `if let` construct takes a branch only if the `let` pattern
matches, currently behind the 'if_let' feature gate.
* 'where clauses', a more flexible syntax for specifying trait
bounds that is more aesthetic, have been added for traits and
free functions. Where clauses will in the future make it
possible to constrain associated types, which would be
impossible with the existing syntax.
* A new slicing syntax (e.g. `[0..4]`) has been introduced behind
the 'slicing_syntax' feature gate, and can be overloaded with
the `Slice` or `SliceMut` traits.
* The syntax for matching of sub-slices has been changed to use a
postfix `..` instead of prefix (.e.g. `[a, b, c..]`), for
consistency with other uses of `..` and to future-proof
potential additional uses of the syntax.
* The syntax for matching inclusive ranges in patterns has changed
from `0..3` to `0...4` to be consistent with the exclusive range
syntax for slicing.
* Matching of sub-slices in non-tail positions (e.g. `[a.., b,
c]`) has been put behind the 'advanced_slice_patterns' feature
gate and may be removed in the future.
* Components of tuples and tuple structs can be extracted using
the `value.0` syntax, currently behind the `tuple_indexing`
feature gate.
* The `#[crate_id]` attribute is no longer supported; versioning
is handled by the package manager.
* Renaming crate imports are now written `extern crate foo as bar`
instead of `extern crate bar = foo`.
* Renaming use statements are now written `use foo as bar` instead
of `use bar = foo`.
* `let` and `match` bindings and argument names in macros are now
hygienic.
* The new, more efficient, closure types ('unboxed closures') have
been added under a feature gate, 'unboxed_closures'. These will
soon replace the existing closure types, once higher-ranked
trait lifetimes are added to the language.
* `move` has been added as a keyword, for indicating closures
that capture by value.
* Mutation and assignment is no longer allowed in pattern guards.
* Generic structs and enums can now have trait bounds.
* The `Share` trait is now called `Sync` to free up the term
'shared' to refer to 'shared reference' (the default reference
type.
* Dynamically-sized types have been mostly implemented,
unifying the behavior of fat-pointer types with the rest of the
type system.
* As part of dynamically-sized types, the `Sized` trait has been
introduced, which qualifying types implement by default, and
which type parameters expect by default. To specify that a type
parameter does not need to be sized, write `<Sized? T>`. Most
types are `Sized`, notable exceptions being unsized arrays
(`[T]`) and trait types.
* Closures can return `!`, as in `|| -> !` or `proc() -> !`.
* Lifetime bounds can now be applied to type parameters and object
types.
* The old, reference counted GC type, `Gc<T>` which was once
denoted by the `@` sigil, has finally been removed. GC will be
revisited in the future.
* Libraries
* Library documentation has been improved for a number of modules.
* Bit-vectors, collections::bitv has been modernized.
* The url crate is deprecated in favor of
http://github.com/servo/rust-url, which can be installed with
Cargo.
* Most I/O stream types can be cloned and subsequently closed from
a different thread.
* A `std::time::Duration` type has been added for use in I/O
methods that rely on timers, as well as in the 'time' crate's
`Timespec` arithmetic.
* The runtime I/O abstraction layer that enabled the green thread
scheduler to do non-thread-blocking I/O has been removed, along
with the libuv-based implementation employed by the green thread
scheduler. This will greatly simplify the future I/O work.
* `collections::btree` has been rewritten to have a more
idiomatic and efficient design.
* Tooling
* rustdoc output now indicates the stability levels of API's.
* The `--crate-name` flag can specify the name of the crate
being compiled, like `#[crate_name]`.
* The `-C metadata` specifies additional metadata to hash into
symbol names, and `-C extra-filename` specifies additional
information to put into the output filename, for use by the
package manager for versioning.
* debug info generation has continued to improve and should be
more reliable under both gdb and lldb.
* rustc has experimental support for compiling in parallel
using the `-C codegen-units` flag.
* rustc no longer encodes rpath information into binaries by
default.
* Misc
* Stack usage has been optimized with LLVM lifetime annotations.
* Official Rust binaries on Linux are more compatible with older
kernels and distributions, built on CentOS 5.10.
Version 0.11.0 (2014-07-02)
==========================
* ~1700 changes, numerous bugfixes
* Language
* ~[T] has been removed from the language. This type is superseded by
the Vec<T> type.
* ~str has been removed from the language. This type is superseded by
the String type.
* ~T has been removed from the language. This type is superseded by the
Box<T> type.
* @T has been removed from the language. This type is superseded by the
standard library's std::gc::Gc<T> type.
* Struct fields are now all private by default.
* Vector indices and shift amounts are both required to be a `uint`
instead of any integral type.
* Byte character, byte string, and raw byte string literals are now all
supported by prefixing the normal literal with a `b`.
* Multiple ABIs are no longer allowed in an ABI string
* The syntax for lifetimes on closures/procedures has been tweaked
slightly: `<'a>|A, B|: 'b + K -> T`
* Floating point modulus has been removed from the language; however it
is still provided by a library implementation.
* Private enum variants are now disallowed.
* The `priv` keyword has been removed from the language.
* A closure can no longer be invoked through a &-pointer.
* The `use foo, bar, baz;` syntax has been removed from the language.
* The transmute intrinsic no longer works on type parameters.
* Statics now allow blocks/items in their definition.
* Trait bounds are separated from objects with + instead of : now.
* Objects can no longer be read while they are mutably borrowed.
* The address of a static is now marked as insignificant unless the
#[inline(never)] attribute is placed it.
* The #[unsafe_destructor] attribute is now behind a feature gate.
* Struct literals are no longer allowed in ambiguous positions such as
if, while, match, and for..in.
* Declaration of lang items and intrinsics are now feature-gated by
default.
* Integral literals no longer default to `int`, and floating point
literals no longer default to `f64`. Literals must be suffixed with an
appropriate type if inference cannot determine the type of the
literal.
* The Box<T> type is no longer implicitly borrowed to &mut T.
* Procedures are now required to not capture borrowed references.
* Libraries
* The standard library is now a "facade" over a number of underlying
libraries. This means that development on the standard library should
be speedier due to smaller crates, as well as a clearer line between
all dependencies.
* A new library, libcore, lives under the standard library's facade
which is Rust's "0-assumption" library, suitable for embedded and
kernel development for example.
* A regex crate has been added to the standard distribution. This crate
includes statically compiled regular expressions.
* The unwrap/unwrap_err methods on Result require a Show bound for
better error messages.
* The return types of the std::comm primitives have been centralized
around the Result type.
* A number of I/O primitives have gained the ability to time out their
operations.
* A number of I/O primitives have gained the ability to close their
reading/writing halves to cancel pending operations.
* Reverse iterator methods have been removed in favor of `rev()` on
their forward-iteration counterparts.
* A bitflags! macro has been added to enable easy interop with C and
management of bit flags.
* A debug_assert! macro is now provided which is disabled when
`--cfg ndebug` is passed to the compiler.
* A graphviz crate has been added for creating .dot files.
* The std::cast module has been migrated into std::mem.
* The std::local_data api has been migrated from freestanding functions
to being based on methods.
* The Pod trait has been renamed to Copy.
* jemalloc has been added as the default allocator for types.
* The API for allocating memory has been changed to use proper alignment
and sized deallocation
* Connecting a TcpStream or binding a TcpListener is now based on a
string address and a u16 port. This allows connecting to a hostname as
opposed to an IP.
* The Reader trait now contains a core method, read_at_least(), which
correctly handles many repeated 0-length reads.
* The process-spawning API is now centered around a builder-style
Command struct.
* The :? printing qualifier has been moved from the standard library to
an external libdebug crate.
* Eq/Ord have been renamed to PartialEq/PartialOrd. TotalEq/TotalOrd
have been renamed to Eq/Ord.
* The select/plural methods have been removed from format!. The escapes
for { and } have also changed from \{ and \} to {{ and }},
respectively.
* The TaskBuilder API has been re-worked to be a true builder, and
extension traits for spawning native/green tasks have been added.
* Tooling
* All breaking changes to the language or libraries now have their
commit message annotated with `[breaking-change]` to allow for easy
discovery of breaking changes.
* The compiler will now try to suggest how to annotate lifetimes if a
lifetime-related error occurs.
* Debug info continues to be improved greatly with general bug fixes and
better support for situations like link time optimization (LTO).
* Usage of syntax extensions when cross-compiling has been fixed.
* Functionality equivalent to GCC & Clang's -ffunction-sections,
-fdata-sections and --gc-sections has been enabled by default
* The compiler is now stricter about where it will load module files
from when a module is declared via `mod foo;`.
* The #[phase(syntax)] attribute has been renamed to #[phase(plugin)].
Syntax extensions are now discovered via a "plugin registrar" type
which will be extended in the future to other various plugins.
* Lints have been restructured to allow for dynamically loadable lints.
* A number of rustdoc improvements:
* The HTML output has been visually redesigned.
* Markdown is now powered by hoedown instead of sundown.
* Searching heuristics have been greatly improved.
* The search index has been reduced in size by a great amount.
* Cross-crate documentation via `pub use` has been greatly improved.
* Primitive types are now hyperlinked and documented.
* Documentation has been moved from static.rust-lang.org/doc to
doc.rust-lang.org
* A new sandbox, play.rust-lang.org, is available for running and
sharing rust code examples on-line.
* Unused attributes are now more robustly warned about.
* The dead_code lint now warns about unused struct fields.
* Cross-compiling to iOS is now supported.
* Cross-compiling to mipsel is now supported.
* Stability attributes are now inherited by default and no longer apply
to intra-crate usage, only inter-crate usage.
* Error message related to non-exhaustive match expressions have been
greatly improved.
Version 0.10 (2014-04-03)
=========================
* ~1500 changes, numerous bugfixes
* Language
* A new RFC process is now in place for modifying the language.
* Patterns with `@`-pointers have been removed from the language.
* Patterns with unique vectors (`~[T]`) have been removed from the
language.
* Patterns with unique strings (`~str`) have been removed from the
language.
* `@str` has been removed from the language.
* `@[T]` has been removed from the language.
* `@self` has been removed from the language.
* `@Trait` has been removed from the language.
* Headers on `~` allocations which contain `@` boxes inside the type for
reference counting have been removed.
* The semantics around the lifetimes of temporary expressions have changed,
see #3511 and #11585 for more information.
* Cross-crate syntax extensions are now possible, but feature gated. See
#11151 for more information. This includes both `macro_rules!` macros as
well as syntax extensions such as `format!`.
* New lint modes have been added, and older ones have been turned on to be
warn-by-default.
* Unnecessary parentheses
* Uppercase statics
* Camel Case types
* Uppercase variables
* Publicly visible private types
* `#[deriving]` with raw pointers
* Unsafe functions can no longer be coerced to closures.
* Various obscure macros such as `log_syntax!` are now behind feature gates.
* The `#[simd]` attribute is now behind a feature gate.
* Visibility is no longer allowed on `extern crate` statements, and
unnecessary visibility (`priv`) is no longer allowed on `use` statements.
* Trailing commas are now allowed in argument lists and tuple patterns.
* The `do` keyword has been removed, it is now a reserved keyword.
* Default type parameters have been implemented, but are feature gated.
* Borrowed variables through captures in closures are now considered soundly.
* `extern mod` is now `extern crate`
* The `Freeze` trait has been removed.
* The `Share` trait has been added for types that can be shared among
threads.
* Labels in macros are now hygienic.
* Expression/statement macro invocations can be delimited with `{}` now.
* Treatment of types allowed in `static mut` locations has been tweaked.
* The `*` and `.` operators are now overloadable through the `Deref` and
`DerefMut` traits.
* `~Trait` and `proc` no longer have `Send` bounds by default.
* Partial type hints are now supported with the `_` type marker.
* An `Unsafe` type was introduced for interior mutability. It is now
considered undefined to transmute from `&T` to `&mut T` without using the
`Unsafe` type.
* The #[linkage] attribute was implemented for extern statics/functions.
* The inner attribute syntax has changed from `#[foo];` to `#![foo]`.
* `Pod` was renamed to `Copy`.
* Libraries
* The `libextra` library has been removed. It has now been decomposed into
component libraries with smaller and more focused nuggets of
functionality. The full list of libraries can be found on the
documentation index page.
* std: `std::condition` has been removed. All I/O errors are now propagated
through the `Result` type. In order to assist with error handling, a
`try!` macro for unwrapping errors with an early return and a lint for
unused results has been added. See #12039 for more information.
* std: The `vec` module has been renamed to `slice`.
* std: A new vector type, `Vec<T>`, has been added in preparation for DST.
This will become the only growable vector in the future.
* std: `std::io` now has more public-reexports. Types such as `BufferedReader`
are now found at `std::io::BufferedReader` instead of
`std::io::buffered::BufferedReader`.
* std: `print` and `println` are no longer in the prelude, the `print!` and
`println!` macros are intended to be used instead.
* std: `Rc` now has a `Weak` pointer for breaking cycles, and it no longer
attempts to statically prevent cycles.
* std: The standard distribution is adopting the policy of pushing failure
to the user rather than failing in libraries. Many functions (such as
`slice::last()`) now return `Option<T>` instead of `T` + failing.
* std: `fmt::Default` has been renamed to `fmt::Show`, and it now has a new
deriving mode: `#[deriving(Show)]`.
* std: `ToStr` is now implemented for all types implementing `Show`.
* std: The formatting trait methods now take `&self` instead of `&T`
* std: The `invert()` method on iterators has been renamed to `rev()`
* std: `std::num` has seen a reduction in the genericity of its traits,
consolidating functionality into a few core traits.
* std: Backtraces are now printed on task failure if the environment
variable `RUST_BACKTRACE` is present.
* std: Naming conventions for iterators have been standardized. More details
can be found on the wiki's style guide.
* std: `eof()` has been removed from the `Reader` trait. Specific types may
still implement the function.
* std: Networking types are now cloneable to allow simultaneous reads/writes.
* std: `assert_approx_eq!` has been removed
* std: The `e` and `E` formatting specifiers for floats have been added to
print them in exponential notation.
* std: The `Times` trait has been removed
* std: Indications of variance and opting out of builtin bounds is done
through marker types in `std::kinds::marker` now
* std: `hash` has been rewritten, `IterBytes` has been removed, and
`#[deriving(Hash)]` is now possible.
* std: `SharedChan` has been removed, `Sender` is now cloneable.
* std: `Chan` and `Port` were renamed to `Sender` and `Receiver`.
* std: `Chan::new` is now `channel()`.
* std: A new synchronous channel type has been implemented.
* std: A `select!` macro is now provided for selecting over `Receiver`s.
* std: `hashmap` and `trie` have been moved to `libcollections`
* std: `run` has been rolled into `io::process`
* std: `assert_eq!` now uses `{}` instead of `{:?}`
* std: The equality and comparison traits have seen some reorganization.
* std: `rand` has moved to `librand`.
* std: `to_{lower,upper}case` has been implemented for `char`.
* std: Logging has been moved to `liblog`.
* collections: `HashMap` has been rewritten for higher performance and less
memory usage.
* native: The default runtime is now `libnative`. If `libgreen` is desired,
it can be booted manually. The runtime guide has more information and
examples.
* native: All I/O functionality except signals has been implemented.
* green: Task spawning with `libgreen` has been optimized with stack caching
and various trimming of code.
* green: Tasks spawned by `libgreen` now have an unmapped guard page.
* sync: The `extra::sync` module has been updated to modern rust (and moved
to the `sync` library), tweaking and improving various interfaces while
dropping redundant functionality.
* sync: A new `Barrier` type has been added to the `sync` library.
* sync: An efficient mutex for native and green tasks has been implemented.
* serialize: The `base64` module has seen some improvement. It treats
newlines better, has non-string error values, and has seen general
cleanup.
* fourcc: A `fourcc!` macro was introduced
* hexfloat: A `hexfloat!` macro was implemented for specifying floats via a
hexadecimal literal.
* Tooling
* `rustpkg` has been deprecated and removed from the main repository. Its
replacement, `cargo`, is under development.
* Nightly builds of rust are now available
* The memory usage of rustc has been improved many times throughout this
release cycle.
* The build process supports disabling rpath support for the rustc binary
itself.
* Code generation has improved in some cases, giving more information to the
LLVM optimization passes to enable more extensive optimizations.
* Debuginfo compatibility with lldb on OSX has been restored.
* The master branch is now gated on an android bot, making building for
android much more reliable.
* Output flags have been centralized into one `--emit` flag.
* Crate type flags have been centralized into one `--crate-type` flag.
* Codegen flags have been consolidated behind a `-C` flag.
* Linking against outdated crates now has improved error messages.
* Error messages with lifetimes will often suggest how to annotate the
function to fix the error.
* Many more types are documented in the standard library, and new guides
were written.
* Many `rustdoc` improvements:
* code blocks are syntax highlighted.
* render standalone markdown files.
* the --test flag tests all code blocks by default.
* exported macros are displayed.
* reexported types have their documentation inlined at the location of the
first reexport.
* search works across crates that have been rendered to the same output
directory.
Version 0.9 (2014-01-09)
==========================
* ~1800 changes, numerous bugfixes
* Language
* The `float` type has been removed. Use `f32` or `f64` instead.
* A new facility for enabling experimental features (feature gating) has
been added, using the crate-level `#[feature(foo)]` attribute.
* Managed boxes (@) are now behind a feature gate
(`#[feature(managed_boxes)]`) in preparation for future removal. Use the
standard library's `Gc` or `Rc` types instead.
* `@mut` has been removed. Use `std::cell::{Cell, RefCell}` instead.
* Jumping back to the top of a loop is now done with `continue` instead of
`loop`.
* Strings can no longer be mutated through index assignment.
* Raw strings can be created via the basic `r"foo"` syntax or with matched
hash delimiters, as in `r###"foo"###`.
* `~fn` is now written `proc (args) -> retval { ... }` and may only be
called once.
* The `&fn` type is now written `|args| -> ret` to match the literal form.
* `@fn`s have been removed.
* `do` only works with procs in order to make it obvious what the cost
of `do` is.
* Single-element tuple-like structs can no longer be dereferenced to
obtain the inner value. A more comprehensive solution for overloading
the dereference operator will be provided in the future.
* The `#[link(...)]` attribute has been replaced with
`#[crate_id = "name#vers"]`.
* Empty `impl`s must be terminated with empty braces and may not be
terminated with a semicolon.
* Keywords are no longer allowed as lifetime names; the `self` lifetime
no longer has any special meaning.
* The old `fmt!` string formatting macro has been removed.
* `printf!` and `printfln!` (old-style formatting) removed in favor of
`print!` and `println!`.
* `mut` works in patterns now, as in `let (mut x, y) = (1, 2);`.
* The `extern mod foo (name = "bar")` syntax has been removed. Use
`extern mod foo = "bar"` instead.
* New reserved keywords: `alignof`, `offsetof`, `sizeof`.
* Macros can have attributes.
* Macros can expand to items with attributes.
* Macros can expand to multiple items.
* The `asm!` macro is feature-gated (`#[feature(asm)]`).
* Comments may be nested.
* Values automatically coerce to trait objects they implement, without
an explicit `as`.
* Enum discriminants are no longer an entire word but as small as needed to
contain all the variants. The `repr` attribute can be used to override
the discriminant size, as in `#[repr(int)]` for integer-sized, and
`#[repr(C)]` to match C enums.
* Non-string literals are not allowed in attributes (they never worked).
* The FFI now supports variadic functions.
* Octal numeric literals, as in `0o7777`.
* The `concat!` syntax extension performs compile-time string concatenation.
* The `#[fixed_stack_segment]` and `#[rust_stack]` attributes have been
removed as Rust no longer uses segmented stacks.
* Non-ascii identifiers are feature-gated (`#[feature(non_ascii_idents)]`).
* Ignoring all fields of an enum variant or tuple-struct is done with `..`,
not `*`; ignoring remaining fields of a struct is also done with `..`,
not `_`; ignoring a slice of a vector is done with `..`, not `.._`.
* `rustc` supports the "win64" calling convention via `extern "win64"`.
* `rustc` supports the "system" calling convention, which defaults to the
preferred convention for the target platform, "stdcall" on 32-bit Windows,
"C" elsewhere.
* The `type_overflow` lint (default: warn) checks literals for overflow.
* The `unsafe_block` lint (default: allow) checks for usage of `unsafe`.
* The `attribute_usage` lint (default: warn) warns about unknown
attributes.
* The `unknown_features` lint (default: warn) warns about unknown
feature gates.
* The `dead_code` lint (default: warn) checks for dead code.
* Rust libraries can be linked statically to one another
* `#[link_args]` is behind the `link_args` feature gate.
* Native libraries are now linked with `#[link(name = "foo")]`
* Native libraries can be statically linked to a rust crate
(`#[link(name = "foo", kind = "static")]`).
* Native OS X frameworks are now officially supported
(`#[link(name = "foo", kind = "framework")]`).
* The `#[thread_local]` attribute creates thread-local (not task-local)
variables. Currently behind the `thread_local` feature gate.
* The `return` keyword may be used in closures.
* Types that can be copied via a memcpy implement the `Pod` kind.
* The `cfg` attribute can now be used on struct fields and enum variants.
* Libraries
* std: The `option` and `result` API's have been overhauled to make them
simpler, more consistent, and more composable.
* std: The entire `std::io` module has been replaced with one that is
more comprehensive and that properly interfaces with the underlying
scheduler. File, TCP, UDP, Unix sockets, pipes, and timers are all
implemented.
* std: `io::util` contains a number of useful implementations of
`Reader` and `Writer`, including `NullReader`, `NullWriter`,
`ZeroReader`, `TeeReader`.
* std: The reference counted pointer type `extra::rc` moved into std.
* std: The `Gc` type in the `gc` module will replace `@` (it is currently
just a wrapper around it).
* std: The `Either` type has been removed.
* std: `fmt::Default` can be implemented for any type to provide default
formatting to the `format!` macro, as in `format!("{}", myfoo)`.
* std: The `rand` API continues to be tweaked.
* std: The `rust_begin_unwind` function, useful for inserting breakpoints
on failure in gdb, is now named `rust_fail`.
* std: The `each_key` and `each_value` methods on `HashMap` have been
replaced by the `keys` and `values` iterators.
* std: Functions dealing with type size and alignment have moved from the
`sys` module to the `mem` module.
* std: The `path` module was written and API changed.
* std: `str::from_utf8` has been changed to cast instead of allocate.
* std: `starts_with` and `ends_with` methods added to vectors via the
`ImmutableEqVector` trait, which is in the prelude.
* std: Vectors can be indexed with the `get_opt` method, which returns `None`
if the index is out of bounds.
* std: Task failure no longer propagates between tasks, as the model was
complex, expensive, and incompatible with thread-based tasks.
* std: The `Any` type can be used for dynamic typing.
* std: `~Any` can be passed to the `fail!` macro and retrieved via
`task::try`.
* std: Methods that produce iterators generally do not have an `_iter`
suffix now.
* std: `cell::Cell` and `cell::RefCell` can be used to introduce mutability
roots (mutable fields, etc.). Use instead of e.g. `@mut`.
* std: `util::ignore` renamed to `prelude::drop`.
* std: Slices have `sort` and `sort_by` methods via the `MutableVector`
trait.
* std: `vec::raw` has seen a lot of cleanup and API changes.
* std: The standard library no longer includes any C++ code, and very
minimal C, eliminating the dependency on libstdc++.
* std: Runtime scheduling and I/O functionality has been factored out into
extensible interfaces and is now implemented by two different crates:
libnative, for native threading and I/O; and libgreen, for green threading
and I/O. This paves the way for using the standard library in more limited
embedded environments.
* std: The `comm` module has been rewritten to be much faster, have a
simpler, more consistent API, and to work for both native and green
threading.
* std: All libuv dependencies have been moved into the rustuv crate.
* native: New implementations of runtime scheduling on top of OS threads.
* native: New native implementations of TCP, UDP, file I/O, process spawning,
and other I/O.
* green: The green thread scheduler and message passing types are almost
entirely lock-free.
* extra: The `flatpipes` module had bitrotted and was removed.
* extra: All crypto functions have been removed and Rust now has a policy of
not reimplementing crypto in the standard library. In the future crypto
will be provided by external crates with bindings to established libraries.
* extra: `c_vec` has been modernized.
* extra: The `sort` module has been removed. Use the `sort` method on
mutable slices.
* Tooling
* The `rust` and `rusti` commands have been removed, due to lack of
maintenance.
* `rustdoc` was completely rewritten.
* `rustdoc` can test code examples in documentation.
* `rustpkg` can test packages with the argument, 'test'.
* `rustpkg` supports arbitrary dependencies, including C libraries.
* `rustc`'s support for generating debug info is improved again.
* `rustc` has better error reporting for unbalanced delimiters.
* `rustc`'s JIT support was removed due to bitrot.
* Executables and static libraries can be built with LTO (-Z lto)
* `rustc` adds a `--dep-info` flag for communicating dependencies to
build tools.
Version 0.8 (2013-09-26)
============================
* ~2200 changes, numerous bugfixes
* Language
* The `for` loop syntax has changed to work with the `Iterator` trait.
* At long last, unwinding works on Windows.
* Default methods are ready for use.
* Many trait inheritance bugs fixed.
* Owned and borrowed trait objects work more reliably.
* `copy` is no longer a keyword. It has been replaced by the `Clone` trait.
* rustc can omit emission of code for the `debug!` macro if it is passed
`--cfg ndebug`
* mod.rs is now "blessed". When loading `mod foo;`, rustc will now look
for foo.rs, then foo/mod.rs, and will generate an error when both are
present.
* Strings no longer contain trailing nulls. The new `std::c_str` module
provides new mechanisms for converting to C strings.
* The type of foreign functions is now `extern "C" fn` instead of `*u8'.
* The FFI has been overhauled such that foreign functions are called directly,
instead of through a stack-switching wrapper.
* Calling a foreign function must be done through a Rust function with the
`#[fixed_stack_segment]` attribute.
* The `externfn!` macro can be used to declare both a foreign function and
a `#[fixed_stack_segment]` wrapper at once.
* `pub` and `priv` modifiers on `extern` blocks are no longer parsed.
* `unsafe` is no longer allowed on extern fns - they are all unsafe.
* `priv` is disallowed everywhere except for struct fields and enum variants.
* `&T` (besides `&'static T`) is no longer allowed in `@T`.
* `ref` bindings in irrefutable patterns work correctly now.
* `char` is now prevented from containing invalid code points.
* Casting to `bool` is no longer allowed.
* `\0` is now accepted as an escape in chars and strings.
* `yield` is a reserved keyword.
* `typeof` is a reserved keyword.
* Crates may be imported by URL with `extern mod foo = "url";`.
* Explicit enum discriminants may be given as uints as in `enum E { V = 0u }`
* Static vectors can be initialized with repeating elements,
e.g. `static foo: [u8, .. 100]: [0, .. 100];`.
* Static structs can be initialized with functional record update,
e.g. `static foo: Foo = Foo { a: 5, .. bar };`.
* `cfg!` can be used to conditionally execute code based on the crate
configuration, similarly to `#[cfg(...)]`.
* The `unnecessary_qualification` lint detects unneeded module
prefixes (default: allow).
* Arithmetic operations have been implemented on the SIMD types in
`std::unstable::simd`.
* Exchange allocation headers were removed, reducing memory usage.
* `format!` implements a completely new, extensible, and higher-performance
string formatting system. It will replace `fmt!`.
* `print!` and `println!` write formatted strings (using the `format!`
extension) to stdout.
* `write!` and `writeln!` write formatted strings (using the `format!`
extension) to the new Writers in `std::rt::io`.
* The library section in which a function or static is placed may
be specified with `#[link_section = "..."]`.
* The `proto!` syntax extension for defining bounded message protocols
was removed.
* `macro_rules!` is hygienic for `let` declarations.
* The `#[export_name]` attribute specifies the name of a symbol.
* `unreachable!` can be used to indicate unreachable code, and fails
if executed.
* Libraries
* std: Transitioned to the new runtime, written in Rust.
* std: Added an experimental I/O library, `rt::io`, based on the new
runtime.
* std: A new generic `range` function was added to the prelude, replacing
`uint::range` and friends.
* std: `range_rev` no longer exists. Since range is an iterator it can be
reversed with `range(lo, hi).invert()`.
* std: The `chain` method on option renamed to `and_then`; `unwrap_or_default`
renamed to `unwrap_or`.
* std: The `iterator` module was renamed to `iter`.
* std: Integral types now support the `checked_add`, `checked_sub`, and
`checked_mul` operations for detecting overflow.
* std: Many methods in `str`, `vec`, `option, `result` were renamed for
consistency.
* std: Methods are standardizing on conventions for casting methods:
`to_foo` for copying, `into_foo` for moving, `as_foo` for temporary
and cheap casts.
* std: The `CString` type in `c_str` provides new ways to convert to and
from C strings.
* std: `DoubleEndedIterator` can yield elements in two directions.
* std: The `mut_split` method on vectors partitions an `&mut [T]` into
two splices.
* std: `str::from_bytes` renamed to `str::from_utf8`.
* std: `pop_opt` and `shift_opt` methods added to vectors.
* std: The task-local data interface no longer uses @, and keys are
no longer function pointers.
* std: The `swap_unwrap` method of `Option` renamed to `take_unwrap`.
* std: Added `SharedPort` to `comm`.
* std: `Eq` has a default method for `ne`; only `eq` is required
in implementations.
* std: `Ord` has default methods for `le`, `gt` and `ge`; only `lt`
is required in implementations.
* std: `is_utf8` performance is improved, impacting many string functions.
* std: `os::MemoryMap` provides cross-platform mmap.
* std: `ptr::offset` is now unsafe, but also more optimized. Offsets that
are not 'in-bounds' are considered undefined.
* std: Many freestanding functions in `vec` removed in favor of methods.
* std: Many freestanding functions on scalar types removed in favor of
methods.
* std: Many options to task builders were removed since they don't make
sense in the new scheduler design.
* std: More containers implement `FromIterator` so can be created by the
`collect` method.
* std: More complete atomic types in `unstable::atomics`.
* std: `comm::PortSet` removed.
* std: Mutating methods in the `Set` and `Map` traits have been moved into
the `MutableSet` and `MutableMap` traits. `Container::is_empty`,
`Map::contains_key`, `MutableMap::insert`, and `MutableMap::remove` have
default implementations.
* std: Various `from_str` functions were removed in favor of a generic
`from_str` which is available in the prelude.
* std: `util::unreachable` removed in favor of the `unreachable!` macro.
* extra: `dlist`, the doubly-linked list was modernized.
* extra: Added a `hex` module with `ToHex` and `FromHex` traits.
* extra: Added `glob` module, replacing `std::os::glob`.
* extra: `rope` was removed.
* extra: `deque` was renamed to `ringbuf`. `RingBuf` implements `Deque`.
* extra: `net`, and `timer` were removed. The experimental replacements
are `std::rt::io::net` and `std::rt::io::timer`.
* extra: Iterators implemented for `SmallIntMap`.
* extra: Iterators implemented for `Bitv` and `BitvSet`.
* extra: `SmallIntSet` removed. Use `BitvSet`.
* extra: Performance of JSON parsing greatly improved.
* extra: `semver` updated to SemVer 2.0.0.
* extra: `term` handles more terminals correctly.
* extra: `dbg` module removed.
* extra: `par` module removed.
* extra: `future` was cleaned up, with some method renames.
* extra: Most free functions in `getopts` were converted to methods.
* Other
* rustc's debug info generation (`-Z debug-info`) is greatly improved.
* rustc accepts `--target-cpu` to compile to a specific CPU architecture,
similarly to gcc's `--march` flag.
* rustc's performance compiling small crates is much better.
* rustpkg has received many improvements.
* rustpkg supports git tags as package IDs.
* rustpkg builds into target-specific directories so it can be used for
cross-compiling.
* The number of concurrent test tasks is controlled by the environment
variable RUST_TEST_TASKS.
* The test harness can now report metrics for benchmarks.
* All tools have man pages.
* Programs compiled with `--test` now support the `-h` and `--help` flags.
* The runtime uses jemalloc for allocations.
* Segmented stacks are temporarily disabled as part of the transition to
the new runtime. Stack overflows are possible!
* A new documentation backend, rustdoc_ng, is available for use. It is
still invoked through the normal `rustdoc` command.
Version 0.7 (2013-07-03)
=======================
* ~2000 changes, numerous bugfixes
* Language
* `impl`s no longer accept a visibility qualifier. Put them on methods
instead.
* The borrow checker has been rewritten with flow-sensitivity, fixing
many bugs and inconveniences.
* The `self` parameter no longer implicitly means `&'self self`,
and can be explicitly marked with a lifetime.
* Overloadable compound operators (`+=`, etc.) have been temporarily
removed due to bugs.
* The `for` loop protocol now requires `for`-iterators to return `bool`
so they compose better.
* The `Durable` trait is replaced with the `'static` bounds.
* Trait default methods work more often.
* Structs with the `#[packed]` attribute have byte alignment and
no padding between fields.
* Type parameters bound by `Copy` must now be copied explicitly with
the `copy` keyword.
* It is now illegal to move out of a dereferenced unsafe pointer.
* `Option<~T>` is now represented as a nullable pointer.
* `@mut` does dynamic borrow checks correctly.
* The `main` function is only detected at the topmost level of the crate.
The `#[main]` attribute is still valid anywhere.
* Struct fields may no longer be mutable. Use inherited mutability.
* The `#[no_send]` attribute makes a type that would otherwise be
`Send`, not.
* The `#[no_freeze]` attribute makes a type that would otherwise be
`Freeze`, not.
* Unbounded recursion will abort the process after reaching the limit
specified by the `RUST_MAX_STACK` environment variable (default: 1GB).
* The `vecs_implicitly_copyable` lint mode has been removed. Vectors
are never implicitly copyable.
* `#[static_assert]` makes compile-time assertions about static bools.
* At long last, 'argument modes' no longer exist.
* The rarely used `use mod` statement no longer exists.
* Syntax extensions
* `fail!` and `assert!` accept `~str`, `&'static str` or `fmt!`-style
argument list.
* `Encodable`, `Decodable`, `Ord`, `TotalOrd`, `TotalEq`, `DeepClone`,
`Rand`, `Zero` and `ToStr` can all be automatically derived with
`#[deriving(...)]`.
* The `bytes!` macro returns a vector of bytes for string, u8, char,
and unsuffixed integer literals.
* Libraries
* The `core` crate was renamed to `std`.
* The `std` crate was renamed to `extra`.
* More and improved documentation.
* std: `iterator` module for external iterator objects.
* Many old-style (internal, higher-order function) iterators replaced by
implementations of `Iterator`.
* std: Many old internal vector and string iterators,
incl. `any`, `all`. removed.
* std: The `finalize` method of `Drop` renamed to `drop`.
* std: The `drop` method now takes `&mut self` instead of `&self`.
* std: The prelude no longer reexports any modules, only types and traits.
* std: Prelude additions: `print`, `println`, `FromStr`, `ApproxEq`, `Equiv`,
`Iterator`, `IteratorUtil`, many numeric traits, many tuple traits.
* std: New numeric traits: `Fractional`, `Real`, `RealExt`, `Integer`, `Ratio`,
`Algebraic`, `Trigonometric`, `Exponential`, `Primitive`.
* std: Tuple traits and accessors defined for up to 12-tuples, e.g.
`(0, 1, 2).n2()` or `(0, 1, 2).n2_ref()`.
* std: Many types implement `Clone`.
* std: `path` type renamed to `Path`.
* std: `mut` module and `Mut` type removed.
* std: Many standalone functions removed in favor of methods and iterators
in `vec`, `str`. In the future methods will also work as functions.
* std: `reinterpret_cast` removed. Use `transmute`.
* std: ascii string handling in `std::ascii`.
* std: `Rand` is implemented for ~/@.
* std: `run` module for spawning processes overhauled.
* std: Various atomic types added to `unstable::atomic`.
* std: Various types implement `Zero`.
* std: `LinearMap` and `LinearSet` renamed to `HashMap` and `HashSet`.
* std: Borrowed pointer functions moved from `ptr` to `borrow`.
* std: Added `os::mkdir_recursive`.
* std: Added `os::glob` function performs filesystems globs.
* std: `FuzzyEq` renamed to `ApproxEq`.
* std: `Map` now defines `pop` and `swap` methods.
* std: `Cell` constructors converted to static methods.
* extra: `rc` module adds the reference counted pointers, `Rc` and `RcMut`.
* extra: `flate` module moved from `std` to `extra`.
* extra: `fileinput` module for iterating over a series of files.
* extra: `Complex` number type and `complex` module.
* extra: `Rational` number type and `rational` module.
* extra: `BigInt`, `BigUint` implement numeric and comparison traits.
* extra: `term` uses terminfo now, is more correct.
* extra: `arc` functions converted to methods.
* extra: Implementation of fixed output size variations of SHA-2.
* Tooling
* `unused_variable` lint mode for unused variables (default: warn).
* `unused_unsafe` lint mode for detecting unnecessary `unsafe` blocks
(default: warn).
* `unused_mut` lint mode for identifying unused `mut` qualifiers
(default: warn).
* `dead_assignment` lint mode for unread variables (default: warn).
* `unnecessary_allocation` lint mode detects some heap allocations that are
immediately borrowed so could be written without allocating (default: warn).
* `missing_doc` lint mode (default: allow).
* `unreachable_code` lint mode (default: warn).
* The `rusti` command has been rewritten and a number of bugs addressed.
* rustc outputs in color on more terminals.
* rustc accepts a `--link-args` flag to pass arguments to the linker.
* rustc accepts a `-Z print-link-args` flag for debugging linkage.
* Compiling with `-g` will make the binary record information about
dynamic borrowcheck failures for debugging.
* rustdoc has a nicer stylesheet.
* Various improvements to rustdoc.
* Improvements to rustpkg (see the detailed release notes).
Version 0.6 (2013-04-03)
========================
* ~2100 changes, numerous bugfixes
* Syntax changes
* The self type parameter in traits is now spelled `Self`
* The `self` parameter in trait and impl methods must now be explicitly
named (for example: `fn f(&self) { }`). Implicit self is deprecated.
* Static methods no longer require the `static` keyword and instead
are distinguished by the lack of a `self` parameter
* Replaced the `Durable` trait with the `'static` lifetime
* The old closure type syntax with the trailing sigil has been
removed in favor of the more consistent leading sigil
* `super` is a keyword, and may be prefixed to paths
* Trait bounds are separated with `+` instead of whitespace
* Traits are implemented with `impl Trait for Type`
instead of `impl Type: Trait`
* Lifetime syntax is now `&'l foo` instead of `&l/foo`
* The `export` keyword has finally been removed
* The `move` keyword has been removed (see "Semantic changes")
* The interior mutability qualifier on vectors, `[mut T]`, has been
removed. Use `&mut [T]`, etc.
* `mut` is no longer valid in `~mut T`. Use inherited mutability
* `fail` is no longer a keyword. Use `fail!()`
* `assert` is no longer a keyword. Use `assert!()`
* `log` is no longer a keyword. use `debug!`, etc.
* 1-tuples may be represented as `(T,)`
* Struct fields may no longer be `mut`. Use inherited mutability,
`@mut T`, `core::mut` or `core::cell`
* `extern mod { ... }` is no longer valid syntax for foreign
function modules. Use extern blocks: `extern { ... }`
* Newtype enums removed. Use tuple-structs.
* Trait implementations no longer support visibility modifiers
* Pattern matching over vectors improved and expanded
* `const` renamed to `static` to correspond to lifetime name,
and make room for future `static mut` unsafe mutable globals.
* Replaced `#[deriving_eq]` with `#[deriving(Eq)]`, etc.
* `Clone` implementations can be automatically generated with
`#[deriving(Clone)]`
* Casts to traits must use a pointer sigil, e.g. `@foo as @Bar`
instead of `foo as Bar`.
* Fixed length vector types are now written as `[int, .. 3]`
instead of `[int * 3]`.
* Fixed length vector types can express the length as a constant
expression. (ex: `[int, .. GL_BUFFER_SIZE - 2]`)
* Semantic changes
* Types with owned pointers or custom destructors move by default,
eliminating the `move` keyword
* All foreign functions are considered unsafe
* &mut is now unaliasable
* Writes to borrowed @mut pointers are prevented dynamically
* () has size 0
* The name of the main function can be customized using #[main]
* The default type of an inferred closure is &fn instead of @fn
* `use` statements may no longer be "chained" - they cannot import
identifiers imported by previous `use` statements
* `use` statements are crate relative, importing from the "top"
of the crate by default. Paths may be prefixed with `super::`
or `self::` to change the search behavior.
* Method visibility is inherited from the implementation declaration
* Structural records have been removed
* Many more types can be used in static items, including enums
'static-lifetime pointers and vectors
* Pattern matching over vectors improved and expanded
* Typechecking of closure types has been overhauled to
improve inference and eliminate unsoundness
* Macros leave scope at the end of modules, unless that module is
tagged with #[macro_escape]
* Libraries
* Added big integers to `std::bigint`
* Removed `core::oldcomm` module
* Added pipe-based `core::comm` module
* Numeric traits have been reorganized under `core::num`
* `vec::slice` finally returns a slice
* `debug!` and friends don't require a format string, e.g. `debug!(Foo)`
* Containers reorganized around traits in `core::container`
* `core::dvec` removed, `~[T]` is a drop-in replacement
* `core::send_map` renamed to `core::hashmap`
* `std::map` removed; replaced with `core::hashmap`
* `std::treemap` reimplemented as an owned balanced tree
* `std::deque` and `std::smallintmap` reimplemented as owned containers
* `core::trie` added as a fast ordered map for integer keys
* Set types added to `core::hashmap`, `core::trie` and `std::treemap`
* `Ord` split into `Ord` and `TotalOrd`. `Ord` is still used to
overload the comparison operators, whereas `TotalOrd` is used
by certain container types
* Other
* Replaced the 'cargo' package manager with 'rustpkg'
* Added all-purpose 'rust' tool
* `rustc --test` now supports benchmarks with the `#[bench]` attribute
* rustc now *attempts* to offer spelling suggestions
* Improved support for ARM and Android
* Preliminary MIPS backend
* Improved foreign function ABI implementation for x86, x86_64
* Various memory usage improvements
* Rust code may be embedded in foreign code under limited circumstances
* Inline assembler supported by new asm!() syntax extension.
Version 0.5 (2012-12-21)
===========================
* ~900 changes, numerous bugfixes
* Syntax changes
* Removed `<-` move operator
* Completed the transition from the `#fmt` extension syntax to `fmt!`
* Removed old fixed length vector syntax - `[T]/N`
* New token-based quasi-quoters, `quote_tokens!`, `quote_expr!`, etc.
* Macros may now expand to items and statements
* `a.b()` is always parsed as a method call, never as a field projection
* `Eq` and `IterBytes` implementations can be automatically generated
with `#[deriving_eq]` and `#[deriving_iter_bytes]` respectively
* Removed the special crate language for `.rc` files
* Function arguments may consist of any irrefutable pattern
* Semantic changes
* `&` and `~` pointers may point to objects
* Tuple structs - `struct Foo(Bar, Baz)`. Will replace newtype enums.
* Enum variants may be structs
* Destructors can be added to all nominal types with the Drop trait
* Structs and nullary enum variants may be constants
* Values that cannot be implicitly copied are now automatically moved
without writing `move` explicitly
* `&T` may now be coerced to `*T`
* Coercions happen in `let` statements as well as function calls
* `use` statements now take crate-relative paths
* The module and type namespaces have been merged so that static
method names can be resolved under the trait in which they are
declared
* Improved support for language features
* Trait inheritance works in many scenarios
* More support for explicit self arguments in methods - `self`, `&self`
`@self`, and `~self` all generally work as expected
* Static methods work in more situations
* Experimental: Traits may declare default methods for the implementations
to use
* Libraries
* New condition handling system in `core::condition`
* Timsort added to `std::sort`
* New priority queue, `std::priority_queue`
* Pipes for serializable types, `std::flatpipes'
* Serialization overhauled to be trait-based
* Expanded `getopts` definitions
* Moved futures to `std`
* More functions are pure now
* `core::comm` renamed to `oldcomm`. Still deprecated
* `rustdoc` and `cargo` are libraries now
* Misc
* Added a preliminary REPL, `rusti`
* License changed from MIT to dual MIT/APL2
Version 0.4 (2012-10-15)
==========================
* ~2000 changes, numerous bugfixes
* Syntax
* All keywords are now strict and may not be used as identifiers anywhere
* Keyword removal: 'again', 'import', 'check', 'new', 'owned', 'send',
'of', 'with', 'to', 'class'.
* Classes are replaced with simpler structs
* Explicit method self types
* `ret` became `return` and `alt` became `match`
* `import` is now `use`; `use is now `extern mod`
* `extern mod { ... }` is now `extern { ... }`
* `use mod` is the recommended way to import modules
* `pub` and `priv` replace deprecated export lists
* The syntax of `match` pattern arms now uses fat arrow (=>)
* `main` no longer accepts an args vector; use `os::args` instead
* Semantics
* Trait implementations are now coherent, ala Haskell typeclasses
* Trait methods may be static
* Argument modes are deprecated
* Borrowed pointers are much more mature and recommended for use
* Strings and vectors in the static region are stored in constant memory
* Typestate was removed
* Resolution rewritten to be more reliable
* Support for 'dual-mode' data structures (freezing and thawing)
* Libraries
* Most binary operators can now be overloaded via the traits in
`core::ops'
* `std::net::url` for representing URLs
* Sendable hash maps in `core::send_map`
* `core::task' gained a (currently unsafe) task-local storage API
* Concurrency
* An efficient new intertask communication primitive called the pipe,
along with a number of higher-level channel types, in `core::pipes`
* `std::arc`, an atomically reference counted, immutable, shared memory
type
* `std::sync`, various exotic synchronization tools based on arcs and pipes
* Futures are now based on pipes and sendable
* More robust linked task failure
* Improved task builder API
* Other
* Improved error reporting
* Preliminary JIT support
* Preliminary work on precise GC
* Extensive architectural improvements to rustc
* Begun a transition away from buggy C++-based reflection (shape) code to
Rust-based (visitor) code
* All hash functions and tables converted to secure, randomized SipHash
Version 0.3 (2012-07-12)
========================
* ~1900 changes, numerous bugfixes
* New coding conveniences
* Integer-literal suffix inference
* Per-item control over warnings, errors
* #[cfg(windows)] and #[cfg(unix)] attributes
* Documentation comments
* More compact closure syntax
* 'do' expressions for treating higher-order functions as
control structures
* *-patterns (wildcard extended to all constructor fields)
* Semantic cleanup
* Name resolution pass and exhaustiveness checker rewritten
* Region pointers and borrow checking supersede alias
analysis
* Init-ness checking is now provided by a region-based liveness
pass instead of the typestate pass; same for last-use analysis
* Extensive work on region pointers
* Experimental new language features
* Slices and fixed-size, interior-allocated vectors
* #!-comments for lang versioning, shell execution
* Destructors and iface implementation for classes;
type-parameterized classes and class methods
* 'const' type kind for types that can be used to implement
shared-memory concurrency patterns
* Type reflection
* Removal of various obsolete features
* Keywords: 'be', 'prove', 'syntax', 'note', 'mutable', 'bind',
'crust', 'native' (now 'extern'), 'cont' (now 'again')
* Constructs: do-while loops ('do' repurposed), fn binding,
resources (replaced by destructors)
* Compiler reorganization
* Syntax-layer of compiler split into separate crate
* Clang (from LLVM project) integrated into build
* Typechecker split into sub-modules
* New library code
* New time functions
* Extension methods for many built-in types
* Arc: atomic-refcount read-only / exclusive-use shared cells
* Par: parallel map and search routines
* Extensive work on libuv interface
* Much vector code moved to libraries
* Syntax extensions: #line, #col, #file, #mod, #stringify,
#include, #include_str, #include_bin
* Tool improvements
* Cargo automatically resolves dependencies
Version 0.2 (2012-03-29)
=========================
* >1500 changes, numerous bugfixes
* New docs and doc tooling
* New port: FreeBSD x86_64
* Compilation model enhancements
* Generics now specialized, multiply instantiated
* Functions now inlined across separate crates
* Scheduling, stack and threading fixes
* Noticeably improved message-passing performance
* Explicit schedulers
* Callbacks from C
* Helgrind clean
* Experimental new language features
* Operator overloading
* Region pointers
* Classes
* Various language extensions
* C-callback function types: 'crust fn ...'
* Infinite-loop construct: 'loop { ... }'
* Shorten 'mutable' to 'mut'
* Required mutable-local qualifier: 'let mut ...'
* Basic glob-exporting: 'export foo::*;'
* Alt now exhaustive, 'alt check' for runtime-checked
* Block-function form of 'for' loop, with 'break' and 'ret'.
* New library code
* AST quasi-quote syntax extension
* Revived libuv interface
* New modules: core::{future, iter}, std::arena
* Merged per-platform std::{os*, fs*} to core::{libc, os}
* Extensive cleanup, regularization in libstd, libcore
Version 0.1 (2012-01-20)
===============================
* Most language features work, including:
* Unique pointers, unique closures, move semantics
* Interface-constrained generics
* Static interface dispatch
* Stack growth
* Multithread task scheduling
* Typestate predicates
* Failure unwinding, destructors
* Pattern matching and destructuring assignment
* Lightweight block-lambda syntax
* Preliminary macro-by-example
* Compiler works with the following configurations:
* Linux: x86 and x86_64 hosts and targets
* macOS: x86 and x86_64 hosts and targets
* Windows: x86 hosts and targets
* Cross compilation / multi-target configuration supported.
* Preliminary API-documentation and package-management tools included.
Known issues:
* Documentation is incomplete.
* Performance is below intended target.
* Standard library APIs are subject to extensive change, reorganization.
* Language-level versioning is not yet operational - future code will
break unexpectedly.