Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Partially stabilize const_slice_first_last #86593

Merged
merged 2 commits into from
Aug 2, 2021

Conversation

jhpratt
Copy link
Member

@jhpratt jhpratt commented Jun 24, 2021

This stabilizes the non-mut methods of const_slice_first_last as const. These methods are trivial to implement and have no blockers that I am aware of.

@rustbot label +A-const-fn +S-waiting-on-review +T-libs-api

@rustbot rustbot added A-const-fn Area: const fn foo(..) {..}. Pure functions which can be applied at compile time. S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. T-libs-api Relevant to the library API team, which will review and decide on the PR/issue. labels Jun 24, 2021
@rust-highfive
Copy link
Collaborator

r? @m-ou-se

(rust-highfive has picked a reviewer for you, use r? to override)

@jonas-schievink jonas-schievink added the relnotes Marks issues that should be documented in the release notes of the next release. label Jun 24, 2021
@m-ou-se
Copy link
Member

m-ou-se commented Jul 5, 2021

@rfcbot merge

@rfcbot
Copy link

rfcbot commented Jul 5, 2021

Team member @m-ou-se has proposed to merge this. The next step is review by the rest of the tagged team members:

No concerns currently listed.

Once a majority of reviewers approve (and at most 2 approvals are outstanding), this will enter its final comment period. If you spot a major issue that hasn't been raised at any point in this process, please speak up!

See this document for info about what commands tagged team members can give me.

@rfcbot rfcbot added proposed-final-comment-period Proposed to merge/close by relevant subteam, see T-<team> label. Will enter FCP once signed off. disposition-merge This issue / PR is in PFCP or FCP with a disposition to merge it. final-comment-period In the final comment period and will be merged soon unless new substantive objections are raised. and removed proposed-final-comment-period Proposed to merge/close by relevant subteam, see T-<team> label. Will enter FCP once signed off. labels Jul 5, 2021
@rfcbot
Copy link

rfcbot commented Jul 7, 2021

🔔 This is now entering its final comment period, as per the review above. 🔔

@rfcbot rfcbot added finished-final-comment-period The final comment period is finished for this PR / Issue. to-announce Announce this issue on triage meeting and removed final-comment-period In the final comment period and will be merged soon unless new substantive objections are raised. labels Jul 17, 2021
@rfcbot
Copy link

rfcbot commented Jul 17, 2021

The final comment period, with a disposition to merge, as per the review above, is now complete.

As the automated representative of the governance process, I would like to thank the author for their work and everyone else who contributed.

The RFC will be merged soon.

@m-ou-se
Copy link
Member

m-ou-se commented Aug 1, 2021

@bors r+ rollup

@bors
Copy link
Contributor

bors commented Aug 1, 2021

📌 Commit 9854d30 has been approved by m-ou-se

@bors bors added S-waiting-on-bors Status: Waiting on bors to run and complete tests. Bors will change the label on completion. and removed S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. labels Aug 1, 2021
bors added a commit to rust-lang-ci/rust that referenced this pull request Aug 2, 2021
Rollup of 13 pull requests

Successful merges:

 - rust-lang#86183 (Change environment variable getters to error recoverably)
 - rust-lang#86439 (Remove `Ipv4Addr::is_ietf_protocol_assignment`)
 - rust-lang#86509 (Move `os_str_bytes` to `sys::unix`)
 - rust-lang#86593 (Partially stabilize `const_slice_first_last`)
 - rust-lang#86936 (Add documentation for `Ipv6MulticastScope`)
 - rust-lang#87282 (Ensure `./x.py dist` adheres to `build.tools`)
 - rust-lang#87468 (Update rustfmt)
 - rust-lang#87504 (Update mdbook.)
 - rust-lang#87608 (Remove unused field `Session.system_library_path`)
 - rust-lang#87629 (Consistent spelling of "adapter" in the standard library)
 - rust-lang#87633 (Update compiler_builtins to fix i128 shift/mul on thumbv6m)
 - rust-lang#87644 (Recommend `swap_remove` in `Vec::remove` docs)
 - rust-lang#87653 (mark a UB doctest as no_run)

Failed merges:

r? `@ghost`
`@rustbot` modify labels: rollup
@bors bors merged commit 77d5683 into rust-lang:master Aug 2, 2021
@rustbot rustbot added this to the 1.56.0 milestone Aug 2, 2021
@apiraino
Copy link
Contributor

apiraino commented Aug 5, 2021

@rustbot label -to-announce

@rustbot rustbot removed the to-announce Announce this issue on triage meeting label Aug 5, 2021
@jhpratt jhpratt deleted the stabilize-const_slice_first_last branch August 9, 2021 07:49
wip-sync pushed a commit to NetBSD/pkgsrc-wip that referenced this pull request Oct 22, 2021
Pkgsrc changes:
 * Remove one now-longer-applicable patch, adjust a few others
 * Bump bootstrap requirements to 1.55.0.

Upstream changes:

Version 1.56.0 (2021-10-21)
========================

Language
--------

- [The 2021 Edition is now stable.][rust#88100]
  See [the edition guide][rust-2021-edition-guide] for more details.
- [The pattern in `binding @ pattern` can now also introduce new bindings.]
  [rust#85305]
- [Union field access is permitted in `const fn`.][rust#85769]

[rust-2021-edition-guide]: https://doc.rust-lang.org/nightly/edition-guide/rust-2021/index.html

Compiler
--------

- [Upgrade to LLVM 13.][rust#87570]
- [Support memory, address, and thread sanitizers on
  aarch64-unknown-freebsd.][rust#88023]
- [Allow specifying a deployment target version for all iOS targets][rust#87699]
- [Warnings can be forced on with `--force-warn`.][rust#87472]
  This feature is primarily intended for usage by `cargo fix`,
  rather than end users.
- [Promote `aarch64-apple-ios-sim` to Tier 2\*.][rust#87760]
- [Add `powerpc-unknown-freebsd` at Tier 3\*.][rust#87370]
- [Add `riscv32imc-esp-espidf` at Tier 3\*.][rust#87666]

\* Refer to Rust's [platform support page][platform-support-doc] for more
information on Rust's tiered platform support.

Libraries
---------

- [Allow writing of incomplete UTF-8 sequences via stdout/stderr on Windows.]
  [rust#83342]
  The Windows console still requires valid Unicode, but this change allows
  splitting a UTF-8 character across multiple write calls. This allows, for
  instance, programs that just read and write data buffers (e.g. copying a file
  to stdout) without regard for Unicode or character boundaries.
- [Prefer `AtomicU{64,128}` over Mutex for Instant backsliding protection.]
  [rust#83093]
  For this use case, atomics scale much better under contention.
- [Implement `Extend<(A, B)>` for `(Extend<A>, Extend<B>)`][rust#85835]
- [impl Default, Copy, Clone for std::io::Sink and std::io::Empty][rust#86744]
- [`impl From<[(K, V); N]>` for all collections.][rust#84111]
- [Remove `P: Unpin` bound on impl Future for Pin.][rust#81363]
- [Treat invalid environment variable names as non-existent.][rust#86183]
  Previously, the environment functions would panic if given a
  variable name with an internal null character or equal sign (`=`).
  Now, these functions will just treat such names as non-existent
  variables, since the OS cannot represent the existence of a
  variable with such a name.

Stabilised APIs
---------------

- [`std::os::unix::fs::chroot`]
- [`UnsafeCell::raw_get`]
- [`BufWriter::into_parts`]
- [`core::panic::{UnwindSafe, RefUnwindSafe, AssertUnwindSafe}`]
  These APIs were previously stable in `std`, but are now also available
  in `core`.
- [`Vec::shrink_to`]
- [`String::shrink_to`]
- [`OsString::shrink_to`]
- [`PathBuf::shrink_to`]
- [`BinaryHeap::shrink_to`]
- [`VecDeque::shrink_to`]
- [`HashMap::shrink_to`]
- [`HashSet::shrink_to`]

These APIs are now usable in const contexts:

- [`std::mem::transmute`]
- [`[T]::first`][`slice::first`]
- [`[T]::split_first`][`slice::split_first`]
- [`[T]::last`][`slice::last`]
- [`[T]::split_last`][`slice::split_last`]

Cargo
-----

- [Cargo supports specifying a minimum supported Rust version in Cargo.toml.]
  [`rust-version`] This has no effect at present on dependency
  version selection.  We encourage crates to specify their minimum
  supported Rust version, and we encourage CI systems that support
  Rust code to include a crate's specified minimum version in the
  text matrix for that crate by default.

Compatibility notes
-------------------

- [Update to new argument parsing rules on Windows.][rust#87580]
  This adjusts Rust's standard library to match the behavior of the standard
  libraries for C/C++. The rules have changed slightly over time, and this PR
  brings us to the latest set of rules (changed in 2008).
- [Disallow the aapcs calling convention on aarch64][rust#88399]
  This was already not supported by LLVM; this change surfaces this lack of
  support with a better error message.
- [Make `SEMICOLON_IN_EXPRESSIONS_FROM_MACROS` warn by default][rust#87385]
- [Warn when an escaped newline skips multiple lines.][rust#87671]
- [Calls to `libc::getpid` / `std::process::id` from `Command::pre_exec`
  may return different values on glibc <= 2.24.][rust#81825] Rust
  now invokes the `clone3` system call directly, when available,
  to use new functionality available via that system call. Older
  versions of glibc cache the result of `getpid`, and only update
  that cache when calling glibc's clone/fork functions, so a direct
  system call bypasses that cache update. glibc 2.25 and newer no
  longer cache `getpid` for exactly this reason.

Internal changes
----------------
These changes provide no direct user facing benefits, but represent
significant improvements to the internals and overall performance
of rustc and related tools.

- [LLVM is compiled with PGO in published x86_64-unknown-linux-gnu
  artifacts.][rust#88069] This improves the performance of most Rust builds.

- [Unify representation of macros in internal data structures.][rust#88019]
  This change fixes a host of bugs with the handling of macros by the compiler,
  as well as rustdoc.

[`std::os::unix::fs::chroot`]: https://doc.rust-lang.org/stable/std/os/unix/fs/fn.chroot.html
[`Iterator::intersperse`]: https://doc.rust-lang.org/stable/std/iter/trait.Iterator.html#method.intersperse
[`Iterator::intersperse_with`]: https://doc.rust-lang.org/stable/std/iter/trait.Iterator.html#method.intersperse
[`UnsafeCell::raw_get`]: https://doc.rust-lang.org/stable/std/cell/struct.UnsafeCell.html#method.raw_get
[`BufWriter::into_parts`]: https://doc.rust-lang.org/stable/std/io/struct.BufWriter.html#method.into_parts
[`core::panic::{UnwindSafe, RefUnwindSafe, AssertUnwindSafe}`]: rust-lang/rust#84662
[`Vec::shrink_to`]: https://doc.rust-lang.org/stable/std/vec/struct.Vec.html#method.shrink_to
[`String::shrink_to`]: https://doc.rust-lang.org/stable/std/string/struct.String.html#method.shrink_to
[`OsString::shrink_to`]: https://doc.rust-lang.org/stable/std/ffi/struct.OsString.html#method.shrink_to
[`PathBuf::shrink_to`]: https://doc.rust-lang.org/stable/std/path/struct.PathBuf.html#method.shrink_to
[`BinaryHeap::shrink_to`]: https://doc.rust-lang.org/stable/std/collections/struct.BinaryHeap.html#method.shrink_to
[`VecDeque::shrink_to`]: https://doc.rust-lang.org/stable/std/collections/struct.VecDeque.html#method.shrink_to
[`HashMap::shrink_to`]: https://doc.rust-lang.org/stable/std/collections/hash_map/struct.HashMap.html#method.shrink_to
[`HashSet::shrink_to`]: https://doc.rust-lang.org/stable/std/collections/hash_set/struct.HashSet.html#method.shrink_to
[`std::mem::transmute`]: https://doc.rust-lang.org/stable/std/mem/fn.transmute.html
[`slice::first`]: https://doc.rust-lang.org/stable/std/primitive.slice.html#method.first
[`slice::split_first`]: https://doc.rust-lang.org/stable/std/primitive.slice.html#method.split_first
[`slice::last`]: https://doc.rust-lang.org/stable/std/primitive.slice.html#method.last
[`slice::split_last`]: https://doc.rust-lang.org/stable/std/primitive.slice.html#method.split_last
[`rust-version`]: https://doc.rust-lang.org/nightly/cargo/reference/manifest.html#the-rust-version-field
[rust#87671]: rust-lang/rust#87671
[rust#86183]: rust-lang/rust#86183
[rust#87385]: rust-lang/rust#87385
[rust#88100]: rust-lang/rust#88100
[rust#86860]: rust-lang/rust#86860
[rust#84039]: rust-lang/rust#84039
[rust#86492]: rust-lang/rust#86492
[rust#88363]: rust-lang/rust#88363
[rust#85305]: rust-lang/rust#85305
[rust#87832]: rust-lang/rust#87832
[rust#88069]: rust-lang/rust#88069
[rust#87472]: rust-lang/rust#87472
[rust#87699]: rust-lang/rust#87699
[rust#87570]: rust-lang/rust#87570
[rust#88023]: rust-lang/rust#88023
[rust#87760]: rust-lang/rust#87760
[rust#87370]: rust-lang/rust#87370
[rust#87580]: rust-lang/rust#87580
[rust#83342]: rust-lang/rust#83342
[rust#83093]: rust-lang/rust#83093
[rust#88177]: rust-lang/rust#88177
[rust#88548]: rust-lang/rust#88548
[rust#88551]: rust-lang/rust#88551
[rust#88299]: rust-lang/rust#88299
[rust#88220]: rust-lang/rust#88220
[rust#85835]: rust-lang/rust#85835
[rust#86879]: rust-lang/rust#86879
[rust#86744]: rust-lang/rust#86744
[rust#84662]: rust-lang/rust#84662
[rust#86593]: rust-lang/rust#86593
[rust#81050]: rust-lang/rust#81050
[rust#81363]: rust-lang/rust#81363
[rust#84111]: rust-lang/rust#84111
[rust#85769]: rust-lang/rust#85769 (comment)
[rust#88490]: rust-lang/rust#88490
[rust#88269]: rust-lang/rust#88269
[rust#84176]: rust-lang/rust#84176
[rust#88399]: rust-lang/rust#88399
[rust#88227]: rust-lang/rust#88227
[rust#88200]: rust-lang/rust#88200
[rust#82776]: rust-lang/rust#82776
[rust#88077]: rust-lang/rust#88077
[rust#87728]: rust-lang/rust#87728
[rust#87050]: rust-lang/rust#87050
[rust#87619]: rust-lang/rust#87619
[rust#81825]: rust-lang/rust#81825 (comment)
[rust#88019]: rust-lang/rust#88019
[rust#87666]: rust-lang/rust#87666
netbsd-srcmastr pushed a commit to NetBSD/pkgsrc that referenced this pull request Nov 20, 2021
Pkgsrc changes:
 * Bump bootstrap kit version to 1.55.0.
 * Adjust patches as needed, some no longer apply (so removed)
 * Update checksum adjustments.
 * Avoid rust-llvm on SunOS
 * Optionally build docs
 * Remove reference to closed/old PR#54621

Upstream changes:

Version 1.56.1 (2021-11-01)
===========================

- New lints to detect the presence of bidirectional-override Unicode
  codepoints in the compiled source code ([CVE-2021-42574])

[CVE-2021-42574]: https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-42574

Version 1.56.0 (2021-10-21)
========================

Language
--------

- [The 2021 Edition is now stable.][rust#88100]
  See [the edition guide][rust-2021-edition-guide] for more details.
- [The pattern in `binding @ pattern` can now also introduce new bindings.]
  [rust#85305]
- [Union field access is permitted in `const fn`.][rust#85769]

[rust-2021-edition-guide]:
  https://doc.rust-lang.org/nightly/edition-guide/rust-2021/index.html

Compiler
--------

- [Upgrade to LLVM 13.][rust#87570]
- [Support memory, address, and thread sanitizers on aarch64-unknown-freebsd.]
  [rust#88023]
- [Allow specifying a deployment target version for all iOS targets][rust#87699]
- [Warnings can be forced on with `--force-warn`.][rust#87472]
  This feature is primarily intended for usage by `cargo fix`, rather than
  end users.
- [Promote `aarch64-apple-ios-sim` to Tier 2\*.][rust#87760]
- [Add `powerpc-unknown-freebsd` at Tier 3\*.][rust#87370]
- [Add `riscv32imc-esp-espidf` at Tier 3\*.][rust#87666]

\* Refer to Rust's [platform support page][platform-support-doc] for more
information on Rust's tiered platform support.

Libraries
---------

- [Allow writing of incomplete UTF-8 sequences via stdout/stderr on Windows.]
  [rust#83342]
  The Windows console still requires valid Unicode, but this change allows
  splitting a UTF-8 character across multiple write calls. This allows, for
  instance, programs that just read and write data buffers (e.g. copying a file
  to stdout) without regard for Unicode or character boundaries.
- [Prefer `AtomicU{64,128}` over Mutex for Instant backsliding protection.]
  [rust#83093]
  For this use case, atomics scale much better under contention.
- [Implement `Extend<(A, B)>` for `(Extend<A>, Extend<B>)`][rust#85835]
- [impl Default, Copy, Clone for std::io::Sink and std::io::Empty][rust#86744]
- [`impl From<[(K, V); N]>` for all collections.][rust#84111]
- [Remove `P: Unpin` bound on impl Future for Pin.][rust#81363]
- [Treat invalid environment variable names as non-existent.][rust#86183]
  Previously, the environment functions would panic if given a
  variable name with an internal null character or equal sign (`=`).
  Now, these functions will just treat such names as non-existent
  variables, since the OS cannot represent the existence of a
  variable with such a name.

Stabilised APIs
---------------

- [`std::os::unix::fs::chroot`]
- [`UnsafeCell::raw_get`]
- [`BufWriter::into_parts`]
- [`core::panic::{UnwindSafe, RefUnwindSafe, AssertUnwindSafe}`]
  These APIs were previously stable in `std`, but are now also available
  in `core`.
- [`Vec::shrink_to`]
- [`String::shrink_to`]
- [`OsString::shrink_to`]
- [`PathBuf::shrink_to`]
- [`BinaryHeap::shrink_to`]
- [`VecDeque::shrink_to`]
- [`HashMap::shrink_to`]
- [`HashSet::shrink_to`]

These APIs are now usable in const contexts:

- [`std::mem::transmute`]
- [`[T]::first`][`slice::first`]
- [`[T]::split_first`][`slice::split_first`]
- [`[T]::last`][`slice::last`]
- [`[T]::split_last`][`slice::split_last`]

Cargo
-----

- [Cargo supports specifying a minimum supported Rust version in Cargo.toml.]
  [`rust-version`]
  This has no effect at present on dependency version selection.
  We encourage crates to specify their minimum supported Rust
  version, and we encourage CI systems that support Rust code to
  include a crate's specified minimum version in the text matrix
  for that crate by default.

Compatibility notes
-------------------

- [Update to new argument parsing rules on Windows.][rust#87580]
  This adjusts Rust's standard library to match the behavior of the standard
  libraries for C/C++. The rules have changed slightly over time, and this PR
  brings us to the latest set of rules (changed in 2008).
- [Disallow the aapcs calling convention on aarch64][rust#88399]
  This was already not supported by LLVM; this change surfaces this lack of
  support with a better error message.
- [Make `SEMICOLON_IN_EXPRESSIONS_FROM_MACROS` warn by default][rust#87385]
- [Warn when an escaped newline skips multiple lines.][rust#87671]
- [Calls to `libc::getpid` / `std::process::id` from `Command::pre_exec`
  may return different values on glibc <= 2.24.][rust#81825]
  Rust now invokes the `clone3` system call directly, when available,
  to use new functionality available via that system call. Older
  versions of glibc cache the result of `getpid`, and only update
  that cache when calling glibc's clone/fork functions, so a direct
  system call bypasses that cache update. glibc 2.25 and newer no
  longer cache `getpid` for exactly this reason.

Internal changes
----------------
These changes provide no direct user facing benefits, but represent
significant improvements to the internals and overall performance
of rustc and related tools.

- [LLVM is compiled with PGO in published x86_64-unknown-linux-gnu artifacts.]
  [rust#88069]
  This improves the performance of most Rust builds.
- [Unify representation of macros in internal data structures.][rust#88019]
  This change fixes a host of bugs with the handling of macros by the compiler,
  as well as rustdoc.

[`std::os::unix::fs::chroot`]: https://doc.rust-lang.org/stable/std/os/unix/fs/fn.chroot.html
[`Iterator::intersperse`]: https://doc.rust-lang.org/stable/std/iter/trait.Iterator.html#method.intersperse
[`Iterator::intersperse_with`]: https://doc.rust-lang.org/stable/std/iter/trait.Iterator.html#method.intersperse
[`UnsafeCell::raw_get`]: https://doc.rust-lang.org/stable/std/cell/struct.UnsafeCell.html#method.raw_get
[`BufWriter::into_parts`]: https://doc.rust-lang.org/stable/std/io/struct.BufWriter.html#method.into_parts
[`core::panic::{UnwindSafe, RefUnwindSafe, AssertUnwindSafe}`]: rust-lang/rust#84662
[`Vec::shrink_to`]: https://doc.rust-lang.org/stable/std/vec/struct.Vec.html#method.shrink_to
[`String::shrink_to`]: https://doc.rust-lang.org/stable/std/string/struct.String.html#method.shrink_to
[`OsString::shrink_to`]: https://doc.rust-lang.org/stable/std/ffi/struct.OsString.html#method.shrink_to
[`PathBuf::shrink_to`]: https://doc.rust-lang.org/stable/std/path/struct.PathBuf.html#method.shrink_to
[`BinaryHeap::shrink_to`]: https://doc.rust-lang.org/stable/std/collections/struct.BinaryHeap.html#method.shrink_to
[`VecDeque::shrink_to`]: https://doc.rust-lang.org/stable/std/collections/struct.VecDeque.html#method.shrink_to
[`HashMap::shrink_to`]: https://doc.rust-lang.org/stable/std/collections/hash_map/struct.HashMap.html#method.shrink_to
[`HashSet::shrink_to`]: https://doc.rust-lang.org/stable/std/collections/hash_set/struct.HashSet.html#method.shrink_to
[`std::mem::transmute`]: https://doc.rust-lang.org/stable/std/mem/fn.transmute.html
[`slice::first`]: https://doc.rust-lang.org/stable/std/primitive.slice.html#method.first
[`slice::split_first`]: https://doc.rust-lang.org/stable/std/primitive.slice.html#method.split_first
[`slice::last`]: https://doc.rust-lang.org/stable/std/primitive.slice.html#method.last
[`slice::split_last`]: https://doc.rust-lang.org/stable/std/primitive.slice.html#method.split_last
[`rust-version`]: https://doc.rust-lang.org/nightly/cargo/reference/manifest.html#the-rust-version-field
[rust#87671]: rust-lang/rust#87671
[rust#86183]: rust-lang/rust#86183
[rust#87385]: rust-lang/rust#87385
[rust#88100]: rust-lang/rust#88100
[rust#86860]: rust-lang/rust#86860
[rust#84039]: rust-lang/rust#84039
[rust#86492]: rust-lang/rust#86492
[rust#88363]: rust-lang/rust#88363
[rust#85305]: rust-lang/rust#85305
[rust#87832]: rust-lang/rust#87832
[rust#88069]: rust-lang/rust#88069
[rust#87472]: rust-lang/rust#87472
[rust#87699]: rust-lang/rust#87699
[rust#87570]: rust-lang/rust#87570
[rust#88023]: rust-lang/rust#88023
[rust#87760]: rust-lang/rust#87760
[rust#87370]: rust-lang/rust#87370
[rust#87580]: rust-lang/rust#87580
[rust#83342]: rust-lang/rust#83342
[rust#83093]: rust-lang/rust#83093
[rust#88177]: rust-lang/rust#88177
[rust#88548]: rust-lang/rust#88548
[rust#88551]: rust-lang/rust#88551
[rust#88299]: rust-lang/rust#88299
[rust#88220]: rust-lang/rust#88220
[rust#85835]: rust-lang/rust#85835
[rust#86879]: rust-lang/rust#86879
[rust#86744]: rust-lang/rust#86744
[rust#84662]: rust-lang/rust#84662
[rust#86593]: rust-lang/rust#86593
[rust#81050]: rust-lang/rust#81050
[rust#81363]: rust-lang/rust#81363
[rust#84111]: rust-lang/rust#84111
[rust#85769]: rust-lang/rust#85769 (comment)
[rust#88490]: rust-lang/rust#88490
[rust#88269]: rust-lang/rust#88269
[rust#84176]: rust-lang/rust#84176
[rust#88399]: rust-lang/rust#88399
[rust#88227]: rust-lang/rust#88227
[rust#88200]: rust-lang/rust#88200
[rust#82776]: rust-lang/rust#82776
[rust#88077]: rust-lang/rust#88077
[rust#87728]: rust-lang/rust#87728
[rust#87050]: rust-lang/rust#87050
[rust#87619]: rust-lang/rust#87619
[rust#81825]: rust-lang/rust#81825 (comment)
[rust#88019]: rust-lang/rust#88019
[rust#87666]: rust-lang/rust#87666

Version 1.55.0 (2021-09-09)
============================

Language
--------
- [You can now write open "from" range patterns (`X..`), which will start
  at `X` and will end at the maximum value of the integer.][83918]
- [You can now explicitly import the prelude of different editions
  through `std::prelude` (e.g. `use std::prelude::rust_2021::*;`).][86294]

Compiler
--------
- [Added tier 3\* support for `powerpc64le-unknown-freebsd`.][83572]

\* Refer to Rust's [platform support page][platform-support-doc] for more
   information on Rust's tiered platform support.

Libraries
---------

- [Updated std's float parsing to use the Eisel-Lemire algorithm.][86761]
  These improvements should in general provide faster string parsing of floats,
  no longer reject certain valid floating point values, and reduce
  the produced code size for non-stripped artifacts.
- [`string::Drain` now implements `AsRef<str>` and `AsRef<[u8]>`.][86858]

Stabilised APIs
---------------

- [`Bound::cloned`]
- [`Drain::as_str`]
- [`IntoInnerError::into_error`]
- [`IntoInnerError::into_parts`]
- [`MaybeUninit::assume_init_mut`]
- [`MaybeUninit::assume_init_ref`]
- [`MaybeUninit::write`]
- [`array::map`]
- [`ops::ControlFlow`]
- [`x86::_bittest`]
- [`x86::_bittestandcomplement`]
- [`x86::_bittestandreset`]
- [`x86::_bittestandset`]
- [`x86_64::_bittest64`]
- [`x86_64::_bittestandcomplement64`]
- [`x86_64::_bittestandreset64`]
- [`x86_64::_bittestandset64`]

The following previously stable functions are now `const`.

- [`str::from_utf8_unchecked`]


Cargo
-----
- [Cargo will now deduplicate compiler diagnostics to the terminal when invoking
  rustc in parallel such as when using `cargo test`.][cargo/9675]
- [The package definition in `cargo metadata` now includes the `"default_run"`
  field from the manifest.][cargo/9550]
- [Added `cargo d` as an alias for `cargo doc`.][cargo/9680]
- [Added `{lib}` as formatting option for `cargo tree` to print the `"lib_name"`
  of packages.][cargo/9663]

Rustdoc
-------
- [Added "Go to item on exact match" search option.][85876]
- [The "Implementors" section on traits no longer shows redundant
  method definitions.][85970]
- [Trait implementations are toggled open by default.][86260] This should
  make the implementations more searchable by tools like `CTRL+F` in
  your browser.
- [Intra-doc links should now correctly resolve associated items (e.g. methods)
  through type aliases.][86334]
- [Traits which are marked with `#[doc(hidden)]` will no longer appear in the
  "Trait Implementations" section.][86513]


Compatibility Notes
-------------------
- [std functions that return an `io::Error` will no longer use the
  `ErrorKind::Other` variant.][85746] This is to better reflect that these
  kinds of errors could be categorised [into newer more specific `ErrorKind`
  variants][79965], and that they do not represent a user error.
- [Using environment variable names with `process::Command` on Windows now
  behaves as expected.][85270] Previously using envionment variables with
  `Command` would cause them to be ASCII-uppercased.
- [Rustdoc will now warn on using rustdoc lints that aren't prefixed
  with `rustdoc::`][86849]

[86849]: rust-lang/rust#86849
[86513]: rust-lang/rust#86513
[86334]: rust-lang/rust#86334
[86260]: rust-lang/rust#86260
[85970]: rust-lang/rust#85970
[85876]: rust-lang/rust#85876
[83572]: rust-lang/rust#83572
[86294]: rust-lang/rust#86294
[86858]: rust-lang/rust#86858
[86761]: rust-lang/rust#86761
[85769]: rust-lang/rust#85769
[85746]: rust-lang/rust#85746
[85305]: rust-lang/rust#85305
[85270]: rust-lang/rust#85270
[84111]: rust-lang/rust#84111
[83918]: rust-lang/rust#83918
[79965]: rust-lang/rust#79965
[87370]: rust-lang/rust#87370
[87298]: rust-lang/rust#87298
[cargo/9663]: rust-lang/cargo#9663
[cargo/9675]: rust-lang/cargo#9675
[cargo/9550]: rust-lang/cargo#9550
[cargo/9680]: rust-lang/cargo#9680
[cargo/9663]: rust-lang/cargo#9663
[`array::map`]: https://doc.rust-lang.org/stable/std/primitive.array.html#method.map
[`Bound::cloned`]: https://doc.rust-lang.org/stable/std/ops/enum.Bound.html#method.cloned
[`Drain::as_str`]: https://doc.rust-lang.org/stable/std/string/struct.Drain.html#method.as_str
[`IntoInnerError::into_error`]: https://doc.rust-lang.org/stable/std/io/struct.IntoInnerError.html#method.into_error
[`IntoInnerError::into_parts`]: https://doc.rust-lang.org/stable/std/io/struct.IntoInnerError.html#method.into_parts
[`MaybeUninit::assume_init_mut`]: https://doc.rust-lang.org/stable/std/mem/union.MaybeUninit.html#method.assume_init_mut
[`MaybeUninit::assume_init_ref`]: https://doc.rust-lang.org/stable/std/mem/union.MaybeUninit.html#method.assume_init_ref
[`MaybeUninit::write`]: https://doc.rust-lang.org/stable/std/mem/union.MaybeUninit.html#method.write
[`Seek::rewind`]: https://doc.rust-lang.org/stable/std/io/trait.Seek.html#method.rewind
[`ops::ControlFlow`]: https://doc.rust-lang.org/stable/std/ops/enum.ControlFlow.html
[`str::from_utf8_unchecked`]: https://doc.rust-lang.org/stable/std/str/fn.from_utf8_unchecked.html
[`x86::_bittest`]: https://doc.rust-lang.org/stable/core/arch/x86/fn._bittest.html
[`x86::_bittestandcomplement`]: https://doc.rust-lang.org/stable/core/arch/x86/fn._bittestandcomplement.html
[`x86::_bittestandreset`]: https://doc.rust-lang.org/stable/core/arch/x86/fn._bittestandreset.html
[`x86::_bittestandset`]: https://doc.rust-lang.org/stable/core/arch/x86/fn._bittestandset.html
[`x86_64::_bittest64`]: https://doc.rust-lang.org/stable/core/arch/x86_64/fn._bittest64.html
[`x86_64::_bittestandcomplement64`]: https://doc.rust-lang.org/stable/core/arch/x86_64/fn._bittestandcomplement64.html
[`x86_64::_bittestandreset64`]: https://doc.rust-lang.org/stable/core/arch/x86_64/fn._bittestandreset64.html
[`x86_64::_bittestandset64`]: https://doc.rust-lang.org/stable/core/arch/x86_64/fn._bittestandset64.html
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
Labels
A-const-fn Area: const fn foo(..) {..}. Pure functions which can be applied at compile time. disposition-merge This issue / PR is in PFCP or FCP with a disposition to merge it. finished-final-comment-period The final comment period is finished for this PR / Issue. relnotes Marks issues that should be documented in the release notes of the next release. S-waiting-on-bors Status: Waiting on bors to run and complete tests. Bors will change the label on completion. T-libs-api Relevant to the library API team, which will review and decide on the PR/issue.
Projects
None yet
Development

Successfully merging this pull request may close these issues.

8 participants