Rust 1.5.0

* ~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 and Rc 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 Vecs 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