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merged 1 commit into from
Feb 27, 2024

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ehuss
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@ehuss ehuss commented Feb 26, 2024

This stabilizes the global cache last-use data tracking. This does not stabilize automatic or manual gc.

Tracking issue: #12633

Motivation

The intent is to start getting cargo to collect data so that when we do stabilize automatic gc, there will be a wider range of cargo versions that will be updating the data so the user is less likely to see cache misses due to an over-aggressive gc.

Additionally, this should give us more exposure and time to respond to any problems, such as filesystem issues.

What is stabilized?

Cargo will now automatically create and update an SQLite database, located at $CARGO_HOME/.global-cache. This database tracks timestamps of the last time cargo touched an index, .crate file, extracted crate src directory, git clone, or git checkout. The schema for this database is here.

Cargo updates this file on any command that needs to touch any of those on-disk caches.

The testsuite for this feature is located in global_cache_tracker.rs.

Stabilization risks

There are some risks to stabilizing, since it commits us to staying compatible with the current design.

The concerns I can think of with stabilizing:

This commits us to using the database schema in the current design.

The code is designed to support both backwards and forwards compatible extensions, so I think it should be fairly flexible. Worst case, if we need to make changes that are fundamentally incompatible, then we can switch to a different database filename or tracking approach.

There are certain kinds of errors that are ignored if cargo fails to save the tracking data (see is_silent_error).

The silent errors are only shown with --verbose. This should help deal with read-only filesystem mounts and other issues. Non-silent errors always show just a warning. I don't know if that will be sufficient to avoid problems.

I did a fair bit of testing of performance, and there is a bench suite for this code, but we don't know if there will be pathological problems in the real world. It also incurs an overhead that all builds will have to pay for.

I've done my best to ensure that this should be reliable when used on network or unusual filesystems, but I think those are still a high-risk category. SQLite should be configured to accommodate these cases, as well as the extensive locking code (which has already been enabled).

A call for public testing was announced in December at https://blog.rust-lang.org/2023/12/11/cargo-cache-cleaning.html. At this time, I don't see any issues in Z-gc Nightly: garbage collection that should block this step.

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rustbot commented Feb 26, 2024

r? @weihanglo

rustbot has assigned @weihanglo.
They will have a look at your PR within the next two weeks and either review your PR or reassign to another reviewer.

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@rustbot rustbot added the S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. label Feb 26, 2024
@weihanglo weihanglo added T-cargo Team: Cargo Z-gc Nightly: garbage collection labels Feb 26, 2024
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image image

It seems no objection in the prior discussion on Zulip. Every member on the Cargo team gave 👍🏾👍🏾👍🏾. Should we go through the entire FCP process, giving the community 10 more days for feedback?

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Great job and thanks!

@bors r+

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bors commented Feb 27, 2024

📌 Commit 39863e7 has been approved by weihanglo

It is now in the queue for this repository.

@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 Feb 27, 2024
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bors commented Feb 27, 2024

⌛ Testing commit 39863e7 with merge 98f6bf3...

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bors commented Feb 27, 2024

☀️ Test successful - checks-actions
Approved by: weihanglo
Pushing 98f6bf3 to master...

@bors bors merged commit 98f6bf3 into rust-lang:master Feb 27, 2024
bors added a commit to rust-lang-ci/rust that referenced this pull request Feb 28, 2024
Update cargo

16 commits in 194a60b2952bd5d12ba15dd2577a97eed7d3c587..8964c8ccff6e420e2a38b8696d178d69fab84d9d
2024-02-21 01:53:45 +0000 to 2024-02-27 19:22:46 +0000
- feat: Add "-Zpublic-dependency" for public-dependency feature. (rust-lang/cargo#13340)
- Stabilize global cache data tracking. (rust-lang/cargo#13492)
- chore: bump baseline version requirement of sub crates (rust-lang/cargo#13494)
- fix(doctest): search native libs in build script outputs (rust-lang/cargo#13490)
- chore: fixed a typo(two->too) (rust-lang/cargo#13489)
- test: relax help text assertion (rust-lang/cargo#13488)
- refactor: clean up for `GlobalContext` rename (rust-lang/cargo#13486)
- test(cli): Verify terminal styling (rust-lang/cargo#13461)
- fix(cli): Respect CARGO_TERM_COLOR in '--list' and '-Zhelp' (rust-lang/cargo#13479)
- Error messages when collecting workspace members now mention the workspace root location (rust-lang/cargo#13480)
- fix(add): Improve error when adding registry packages while vendored (rust-lang/cargo#13281)
- [docs]:Add missing jump links (rust-lang/cargo#13478)
- Add global_cache_tracker stability tests. (rust-lang/cargo#13467)
- fix(cli): Control clap colors through config (rust-lang/cargo#13463)
- chore: remove the unused function (rust-lang/cargo#13472)
- Fix missing brackets (rust-lang/cargo#13470)
bors added a commit to rust-lang-ci/rust that referenced this pull request Feb 28, 2024
Update cargo

16 commits in 194a60b2952bd5d12ba15dd2577a97eed7d3c587..8964c8ccff6e420e2a38b8696d178d69fab84d9d
2024-02-21 01:53:45 +0000 to 2024-02-27 19:22:46 +0000
- feat: Add "-Zpublic-dependency" for public-dependency feature. (rust-lang/cargo#13340)
- Stabilize global cache data tracking. (rust-lang/cargo#13492)
- chore: bump baseline version requirement of sub crates (rust-lang/cargo#13494)
- fix(doctest): search native libs in build script outputs (rust-lang/cargo#13490)
- chore: fixed a typo(two->too) (rust-lang/cargo#13489)
- test: relax help text assertion (rust-lang/cargo#13488)
- refactor: clean up for `GlobalContext` rename (rust-lang/cargo#13486)
- test(cli): Verify terminal styling (rust-lang/cargo#13461)
- fix(cli): Respect CARGO_TERM_COLOR in '--list' and '-Zhelp' (rust-lang/cargo#13479)
- Error messages when collecting workspace members now mention the workspace root location (rust-lang/cargo#13480)
- fix(add): Improve error when adding registry packages while vendored (rust-lang/cargo#13281)
- [docs]:Add missing jump links (rust-lang/cargo#13478)
- Add global_cache_tracker stability tests. (rust-lang/cargo#13467)
- fix(cli): Control clap colors through config (rust-lang/cargo#13463)
- chore: remove the unused function (rust-lang/cargo#13472)
- Fix missing brackets (rust-lang/cargo#13470)
@rustbot rustbot added this to the 1.78.0 milestone Feb 28, 2024
wip-sync pushed a commit to NetBSD/pkgsrc-wip that referenced this pull request May 4, 2024
Pkgsrc changes:
 * Adapt checksums and patches, some have beene intregrated upstream.

Upstream chnages:

Version 1.78.0 (2024-05-02)
===========================

Language
--------
- [Stabilize `#[cfg(target_abi = ...)]`]
  (rust-lang/rust#119590)
- [Stabilize the `#[diagnostic]` namespace and
  `#[diagnostic::on_unimplemented]` attribute]
  (rust-lang/rust#119888)
- [Make async-fn-in-trait implementable with concrete signatures]
  (rust-lang/rust#120103)
- [Make matching on NaN a hard error, and remove the rest of
  `illegal_floating_point_literal_pattern`]
  (rust-lang/rust#116284)
- [static mut: allow mutable reference to arbitrary types, not just
  slices and arrays]
  (rust-lang/rust#117614)
- [Extend `invalid_reference_casting` to include references casting
  to bigger memory layout]
  (rust-lang/rust#118983)
- [Add `non_contiguous_range_endpoints` lint for singleton gaps
  after exclusive ranges]
  (rust-lang/rust#118879)
- [Add `wasm_c_abi` lint for use of older wasm-bindgen versions]
  (rust-lang/rust#117918)
  This lint currently only works when using Cargo.
- [Update `indirect_structural_match` and `pointer_structural_match`
  lints to match RFC]
  (rust-lang/rust#120423)
- [Make non-`PartialEq`-typed consts as patterns a hard error]
  (rust-lang/rust#120805)
- [Split `refining_impl_trait` lint into `_reachable`, `_internal` variants]
  (rust-lang/rust#121720)
- [Remove unnecessary type inference when using associated types
  inside of higher ranked `where`-bounds]
  (rust-lang/rust#119849)
- [Weaken eager detection of cyclic types during type inference]
  (rust-lang/rust#119989)
- [`trait Trait: Auto {}`: allow upcasting from `dyn Trait` to `dyn Auto`]
  (rust-lang/rust#119338)

Compiler
--------

- [Made `INVALID_DOC_ATTRIBUTES` lint deny by default]
  (rust-lang/rust#111505)
- [Increase accuracy of redundant `use` checking]
  (rust-lang/rust#117772)
- [Suggest moving definition if non-found macro_rules! is defined later]
  (rust-lang/rust#121130)
- [Lower transmutes from int to pointer type as gep on null]
  (rust-lang/rust#121282)

Target changes:

- [Windows tier 1 targets now require at least Windows 10]
  (rust-lang/rust#115141)
 - [Enable CMPXCHG16B, SSE3, SAHF/LAHF and 128-bit Atomics in tier 1 Windows]
  (rust-lang/rust#120820)
- [Add `wasm32-wasip1` tier 2 (without host tools) target]
  (rust-lang/rust#120468)
- [Add `wasm32-wasip2` tier 3 target]
  (rust-lang/rust#119616)
- [Rename `wasm32-wasi-preview1-threads` to `wasm32-wasip1-threads`]
  (rust-lang/rust#122170)
- [Add `arm64ec-pc-windows-msvc` tier 3 target]
  (rust-lang/rust#119199)
- [Add `armv8r-none-eabihf` tier 3 target for the Cortex-R52]
  (rust-lang/rust#110482)
- [Add `loongarch64-unknown-linux-musl` tier 3 target]
  (rust-lang/rust#121832)

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

Libraries
---------

- [Bump Unicode to version 15.1.0, regenerate tables]
  (rust-lang/rust#120777)
- [Make align_offset, align_to well-behaved in all cases]
  (rust-lang/rust#121201)
- [PartialEq, PartialOrd: document expectations for transitive chains]
  (rust-lang/rust#115386)
- [Optimize away poison guards when std is built with panic=abort]
  (rust-lang/rust#100603)
- [Replace pthread `RwLock` with custom implementation]
  (rust-lang/rust#110211)
- [Implement unwind safety for Condvar on all platforms]
  (rust-lang/rust#121768)
- [Add ASCII fast-path for `char::is_grapheme_extended`]
  (rust-lang/rust#121138)

Stabilized APIs
---------------

- [`impl Read for &Stdin`]
  (https://doc.rust-lang.org/stable/std/io/struct.Stdin.html#impl-Read-for-%26Stdin)
- [Accept non `'static` lifetimes for several `std::error::Error`
  related implementations] (rust-lang/rust#113833)
- [Make `impl<Fd: AsFd>` impl take `?Sized`]
  (rust-lang/rust#114655)
- [`impl From<TryReserveError> for io::Error`]
  (https://doc.rust-lang.org/stable/std/io/struct.Error.html#impl-From%3CTryReserveError%3E-for-Error)

These APIs are now stable in const contexts:

- [`Barrier::new()`]
  (https://doc.rust-lang.org/stable/std/sync/struct.Barrier.html#method.new)

Cargo
-----

- [Stabilize lockfile v4](rust-lang/cargo#12852)
- [Respect `rust-version` when generating lockfile]
  (rust-lang/cargo#12861)
- [Control `--charset` via auto-detecting config value]
  (rust-lang/cargo#13337)
- [Support `target.<triple>.rustdocflags` officially]
  (rust-lang/cargo#13197)
- [Stabilize global cache data tracking]
  (rust-lang/cargo#13492)

Misc
----

- [rustdoc: add `--test-builder-wrapper` arg to support wrappers
  such as RUSTC_WRAPPER when building doctests]
  (rust-lang/rust#114651)

Compatibility Notes
-------------------

- [Many unsafe precondition checks now run for user code with debug
  assertions enabled] (rust-lang/rust#120594)
  This change helps users catch undefined behavior in their code,
  though the details of how much is checked are generally not
  stable.
- [riscv only supports split_debuginfo=off for now]
  (rust-lang/rust#120518)
- [Consistently check bounds on hidden types of `impl Trait`]
  (rust-lang/rust#121679)
- [Change equality of higher ranked types to not rely on subtyping]
  (rust-lang/rust#118247)
- [When called, additionally check bounds on normalized function return type]
  (rust-lang/rust#118882)
- [Expand coverage for `arithmetic_overflow` lint]
  (rust-lang/rust#119432)

Internal Changes
----------------

These changes do not affect any public interfaces of Rust, but they represent
significant improvements to the performance or internals of rustc and related
tools.

- [Update to LLVM 18](rust-lang/rust#120055)
- [Build `rustc` with 1CGU on `x86_64-pc-windows-msvc`]
  (rust-lang/rust#112267)
- [Build `rustc` with 1CGU on `x86_64-apple-darwin`]
  (rust-lang/rust#112268)
- [Introduce `run-make` V2 infrastructure, a `run_make_support`
  library and port over 2 tests as example]
  (rust-lang/rust#113026)
- [Windows: Implement condvar, mutex and rwlock using futex]
  (rust-lang/rust#121956)
netbsd-srcmastr pushed a commit to NetBSD/pkgsrc that referenced this pull request Oct 13, 2024
This is based on the pkgsrc-wip rust180 package, retaining
the main pkgsrc changes as best as I could.

Pkgsrc changes:
 * Adapt checksums and patches.
 * Make this work again on big-endian aarch64 (at least on NetBSD).
 * Make the choice of GCC = 12 work for sparc64 by testing options
   after options.mk is included (which is required...).  Makes this
   work on NetBSD/sparc64 10.0 again.

Upstream chnages:

Version 1.80.1 (2024-08-08)
===========================

- [Fix miscompilation in the jump threading MIR optimization when
  comparing floats]
  (rust-lang/rust#128271)
- [Revert changes to the `dead_code` lint from 1.80.0]
  (rust-lang/rust#128618)

Version 1.80.0 (2024-07-25)
==========================

Language
--------
- [Document maximum allocation size]
  (rust-lang/rust#116675)
- [Allow zero-byte offsets and ZST read/writes on arbitrary pointers]
  (rust-lang/rust#117329)
- [Support C23's variadics without a named parameter]
  (rust-lang/rust#124048)
- [Stabilize `exclusive_range_pattern` feature]
  (rust-lang/rust#124459)
- [Guarantee layout and ABI of `Result` in some scenarios]
  (rust-lang/rust#124870)

Compiler
--------
- [Update cc crate to v1.0.97 allowing additional spectre mitigations
  on MSVC targets]
  (rust-lang/rust#124892)
- [Allow field reordering on types marked `repr(packed(1))`]
  (rust-lang/rust#125360)
- [Add a lint against never type fallback affecting unsafe code]
  (rust-lang/rust#123939)
- [Disallow cast with trailing braced macro in let-else]
  (rust-lang/rust#125049)
- [Expand `for_loops_over_fallibles` lint to lint on fallibles
  behind references.]
  (rust-lang/rust#125156)
- [self-contained linker: retry linking without `-fuse-ld=lld` on
  CCs that don't support it]
  (rust-lang/rust#125417)
- [Do not parse CVarArgs (`...`) as a type in trait bounds]
  (rust-lang/rust#125863)
- Improvements to LLDB formatting [#124458]
  (rust-lang/rust#124458) [#124500]
  (rust-lang/rust#124500)
- [For the wasm32-wasip2 target default to PIC and do not use `-fuse-ld=lld`]
  (rust-lang/rust#124858)
- [Add x86_64-unknown-linux-none as a tier 3 target]
  (rust-lang/rust#125023)
- [Lint on `foo.into_iter()` resolving to `&Box<[T]>: IntoIterator`]
  (rust-lang/rust#124097)

Libraries
---------
- [Add `size_of` and `size_of_val` and `align_of` and `align_of_val`
  to the prelude]
  (rust-lang/rust#123168)
- [Abort a process when FD ownership is violated]
  (rust-lang/rust#124210)
- [io::Write::write_fmt: panic if the formatter fails when the
  stream does not fail]
  (rust-lang/rust#125012)
- [Panic if `PathBuf::set_extension` would add a path separator]
  (rust-lang/rust#125070)
- [Add assert_unsafe_precondition to unchecked_{add,sub,neg,mul,shl,shr}
  methods] (rust-lang/rust#121571)
- [Update `c_char` on AIX to use the correct type]
  (rust-lang/rust#122986)
- [`offset_of!` no longer returns a temporary]
  (rust-lang/rust#124484)
- [Handle sigma in `str.to_lowercase` correctly]
  (rust-lang/rust#124773)
- [Raise `DEFAULT_MIN_STACK_SIZE` to at least 64KiB]
  (rust-lang/rust#126059)

Stabilized APIs
---------------
- [`impl Default for Rc<CStr>`]
  (https://doc.rust-lang.org/beta/alloc/rc/struct.Rc.html#impl-Default-for-Rc%3CCStr%3E)
- [`impl Default for Rc<str>`]
  (https://doc.rust-lang.org/beta/alloc/rc/struct.Rc.html#impl-Default-for-Rc%3Cstr%3E)
- [`impl Default for Rc<[T]>`]
  (https://doc.rust-lang.org/beta/alloc/rc/struct.Rc.html#impl-Default-for-Rc%3C%5BT%5D%3E)
- [`impl Default for Arc<str>`]
  (https://doc.rust-lang.org/beta/alloc/sync/struct.Arc.html#impl-Default-for-Arc%3Cstr%3E)
- [`impl Default for Arc<CStr>`]
  (https://doc.rust-lang.org/beta/alloc/sync/struct.Arc.html#impl-Default-for-Arc%3CCStr%3E)
- [`impl Default for Arc<[T]>`]
  (https://doc.rust-lang.org/beta/alloc/sync/struct.Arc.html#impl-Default-for-Arc%3C%5BT%5D%3E)
- [`impl IntoIterator for Box<[T]>`]
  (https://doc.rust-lang.org/beta/alloc/boxed/struct.Box.html#impl-IntoIterator-for-Box%3C%5BI%5D,+A%3E)
- [`impl FromIterator<String> for Box<str>`]
  (https://doc.rust-lang.org/beta/alloc/boxed/struct.Box.html#impl-FromIterator%3CString%3E-for-Box%3Cstr%3E)
- [`impl FromIterator<char> for Box<str>`]
  (https://doc.rust-lang.org/beta/alloc/boxed/struct.Box.html#impl-FromIterator%3Cchar%3E-for-Box%3Cstr%3E)
- [`LazyCell`]
  (https://doc.rust-lang.org/beta/core/cell/struct.LazyCell.html)
- [`LazyLock`]
  (https://doc.rust-lang.org/beta/std/sync/struct.LazyLock.html)
- [`Duration::div_duration_f32`]
  (https://doc.rust-lang.org/beta/std/time/struct.Duration.html#method.div_duration_f32)
- [`Duration::div_duration_f64`]
  (https://doc.rust-lang.org/beta/std/time/struct.Duration.html#method.div_duration_f64)
- [`Option::take_if`]
  (https://doc.rust-lang.org/beta/std/option/enum.Option.html#method.take_if)
- [`Seek::seek_relative`]
  (https://doc.rust-lang.org/beta/std/io/trait.Seek.html#method.seek_relative)
- [`BinaryHeap::as_slice`]
  (https://doc.rust-lang.org/beta/std/collections/struct.BinaryHeap.html#method.as_slice)
- [`NonNull::offset`]
  (https://doc.rust-lang.org/beta/std/ptr/struct.NonNull.html#method.offset)
- [`NonNull::byte_offset`]
  (https://doc.rust-lang.org/beta/std/ptr/struct.NonNull.html#method.byte_offset)
- [`NonNull::add`]
  (https://doc.rust-lang.org/beta/std/ptr/struct.NonNull.html#method.add)
- [`NonNull::byte_add`]
  (https://doc.rust-lang.org/beta/std/ptr/struct.NonNull.html#method.byte_add)
- [`NonNull::sub`]
  (https://doc.rust-lang.org/beta/std/ptr/struct.NonNull.html#method.sub)
- [`NonNull::byte_sub`]
  (https://doc.rust-lang.org/beta/std/ptr/struct.NonNull.html#method.byte_sub)
- [`NonNull::offset_from`]
  (https://doc.rust-lang.org/beta/std/ptr/struct.NonNull.html#method.offset_from)
- [`NonNull::byte_offset_from`]
  (https://doc.rust-lang.org/beta/std/ptr/struct.NonNull.html#method.byte_offset_from)
- [`NonNull::read`]
  (https://doc.rust-lang.org/beta/std/ptr/struct.NonNull.html#method.read)
- [`NonNull::read_volatile`]
  (https://doc.rust-lang.org/beta/std/ptr/struct.NonNull.html#method.read_volatile)
- [`NonNull::read_unaligned`]
  (https://doc.rust-lang.org/beta/std/ptr/struct.NonNull.html#method.read_unaligned)
- [`NonNull::write`]
  (https://doc.rust-lang.org/beta/std/ptr/struct.NonNull.html#method.write)
- [`NonNull::write_volatile`]
  (https://doc.rust-lang.org/beta/std/ptr/struct.NonNull.html#method.write_volatile)
- [`NonNull::write_unaligned`]
  (https://doc.rust-lang.org/beta/std/ptr/struct.NonNull.html#method.write_unaligned)
- [`NonNull::write_bytes`]
  (https://doc.rust-lang.org/beta/std/ptr/struct.NonNull.html#method.write_bytes)
- [`NonNull::copy_to`]
  (https://doc.rust-lang.org/beta/std/ptr/struct.NonNull.html#method.copy_to)
- [`NonNull::copy_to_nonoverlapping`]
  (https://doc.rust-lang.org/beta/std/ptr/struct.NonNull.html#method.copy_to_nonoverlapping)
- [`NonNull::copy_from`]
  (https://doc.rust-lang.org/beta/std/ptr/struct.NonNull.html#method.copy_from)
- [`NonNull::copy_from_nonoverlapping`]
  (https://doc.rust-lang.org/beta/std/ptr/struct.NonNull.html#method.copy_from_nonoverlapping)
- [`NonNull::replace`]
  (https://doc.rust-lang.org/beta/std/ptr/struct.NonNull.html#method.replace)
- [`NonNull::swap`]
  (https://doc.rust-lang.org/beta/std/ptr/struct.NonNull.html#method.swap)
- [`NonNull::drop_in_place`]
  (https://doc.rust-lang.org/beta/std/ptr/struct.NonNull.html#method.drop_in_place)
- [`NonNull::align_offset`]
  (https://doc.rust-lang.org/beta/std/ptr/struct.NonNull.html#method.align_offset)
- [`<[T]>::split_at_checked`]
  (https://doc.rust-lang.org/beta/std/primitive.slice.html#method.split_at_checked)
- [`<[T]>::split_at_mut_checked`]
  (https://doc.rust-lang.org/beta/std/primitive.slice.html#method.split_at_mut_checked)
- [`str::split_at_checked`]
  (https://doc.rust-lang.org/beta/std/primitive.str.html#method.split_at_checked)
- [`str::split_at_mut_checked`]
  (https://doc.rust-lang.org/beta/std/primitive.str.html#method.split_at_mut_checked)
- [`str::trim_ascii`]
  (https://doc.rust-lang.org/beta/std/primitive.str.html#method.trim_ascii)
- [`str::trim_ascii_start`]
  (https://doc.rust-lang.org/beta/std/primitive.str.html#method.trim_ascii_start)
- [`str::trim_ascii_end`]
  (https://doc.rust-lang.org/beta/std/primitive.str.html#method.trim_ascii_end)
- [`<[u8]>::trim_ascii`]
  (https://doc.rust-lang.org/beta/core/primitive.slice.html#method.trim_ascii)
- [`<[u8]>::trim_ascii_start`]
  (https://doc.rust-lang.org/beta/core/primitive.slice.html#method.trim_ascii_start)
- [`<[u8]>::trim_ascii_end`]
  (https://doc.rust-lang.org/beta/core/primitive.slice.html#method.trim_ascii_end)
- [`Ipv4Addr::BITS`]
  (https://doc.rust-lang.org/beta/core/net/struct.Ipv4Addr.html#associatedconstant.BITS)
- [`Ipv4Addr::to_bits`]
  (https://doc.rust-lang.org/beta/core/net/struct.Ipv4Addr.html#method.to_bits)
- [`Ipv4Addr::from_bits`]
  (https://doc.rust-lang.org/beta/core/net/struct.Ipv4Addr.html#method.from_bits)
- [`Ipv6Addr::BITS`]
  (https://doc.rust-lang.org/beta/core/net/struct.Ipv6Addr.html#associatedconstant.BITS)
- [`Ipv6Addr::to_bits`]
  (https://doc.rust-lang.org/beta/core/net/struct.Ipv6Addr.html#method.to_bits)
- [`Ipv6Addr::from_bits`]
  (https://doc.rust-lang.org/beta/core/net/struct.Ipv6Addr.html#method.from_bits)
- [`Vec::<[T; N]>::into_flattened`]
  (https://doc.rust-lang.org/beta/alloc/vec/struct.Vec.html#method.into_flattened)
- [`<[[T; N]]>::as_flattened`]
  (https://doc.rust-lang.org/beta/core/primitive.slice.html#method.as_flattened)
- [`<[[T; N]]>::as_flattened_mut`]
  (https://doc.rust-lang.org/beta/core/primitive.slice.html#method.as_flattened_mut)

These APIs are now stable in const contexts:

- [`<[T]>::last_chunk`]
  (https://doc.rust-lang.org/beta/core/primitive.slice.html#method.last_chunk)
- [`BinaryHeap::new`]
  (https://doc.rust-lang.org/beta/std/collections/struct.BinaryHeap.html#method.new)

Cargo
-----

- [Stabilize `-Zcheck-cfg` as always enabled]
  (rust-lang/cargo#13571)
- [Warn, rather than fail publish, if a target is excluded]
  (rust-lang/cargo#13713)
- [Add special `check-cfg` lint config for the `unexpected_cfgs` lint]
  (rust-lang/cargo#13913)
- [Stabilize `cargo update --precise <yanked>`]
  (rust-lang/cargo#13974)
- [Don't change file permissions on `Cargo.toml` when using `cargo add`]
  (rust-lang/cargo#13898)
- [Support using `cargo fix` on IPv6-only networks]
  (rust-lang/cargo#13907)

Rustdoc
-----

- [Allow searching for references]
  (rust-lang/rust#124148)
- [Stabilize `custom_code_classes_in_docs` feature]
  (rust-lang/rust#124577)
- [fix: In cross-crate scenarios show enum variants on type aliases of enums]
  (rust-lang/rust#125300)

Compatibility Notes
-------------------

- [rustfmt estimates line lengths differently when using non-ascii characters]
  (rust-lang/rustfmt#6203)
- [Type aliases are now handled correctly in orphan check]
  (rust-lang/rust#117164)
- [Allow instructing rustdoc to read from stdin via `-`]
  (rust-lang/rust#124611)
- [`std::env::{set_var, remove_var}` can no longer be converted to
  safe function pointers and no longer implement the `Fn` family of
  traits]
  (rust-lang/rust#124636)
- [Warn (or error) when `Self` constructor from outer item is
  referenced in inner nested item]
  (rust-lang/rust#124187)
- [Turn `indirect_structural_match` and `pointer_structural_match`
  lints into hard errors]
  (rust-lang/rust#124661)
- [Make `where_clause_object_safety` lint a regular object safety violation]
  (rust-lang/rust#125380)
- [Turn `proc_macro_back_compat` lint into a hard error.]
  (rust-lang/rust#125596)
- [Detect unused structs even when implementing private traits]
  (rust-lang/rust#122382)
- [`std::sync::ReentrantLockGuard<T>` is no longer `Sync` if `T: !Sync`]
  (rust-lang/rust#125527) which means
  [`std::io::StdoutLock` and `std::io::StderrLock` are no longer
  Sync] (rust-lang/rust#127340)

Internal Changes
----------------

These changes do not affect any public interfaces of Rust, but they represent
significant improvements to the performance or internals of rustc and related
tools.

- Misc improvements to size of generated html by rustdoc e.g. [#124738]
  (rust-lang/rust#124738) and [#123734]
  (rust-lang/rust#123734)
- [MSVC targets no longer depend on libc]
  (rust-lang/rust#124050)


Version 1.79.0 (2024-06-13)
==========================

Language
--------
- [Stabilize inline `const {}` expressions.]
  (rust-lang/rust#104087)
- [Prevent opaque types being instantiated twice with different
  regions within the same function.]
  (rust-lang/rust#116935)
- [Stabilize WebAssembly target features that are in phase 4 and 5.]
  (rust-lang/rust#117457)
- [Add the `redundant_lifetimes` lint to detect lifetimes which
  are semantically redundant.]
  (rust-lang/rust#118391)
- [Stabilize the `unnameable_types` lint for public types that can't be named.]
  (rust-lang/rust#120144)
- [Enable debuginfo in macros, and stabilize `-C collapse-macro-debuginfo`
  and `#[collapse_debuginfo]`.]
  (rust-lang/rust#120845)
- [Propagate temporary lifetime extension into `if` and `match` expressions.]
  (rust-lang/rust#121346)
- [Restrict promotion of `const fn` calls.]
  (rust-lang/rust#121557)
- [Warn against refining impls of crate-private traits with
  `refining_impl_trait` lint.]
  (rust-lang/rust#121720)
- [Stabilize associated type bounds (RFC 2289).]
  (rust-lang/rust#122055)
- [Stabilize importing `main` from other modules or crates.]
  (rust-lang/rust#122060)
- [Check return types of function types for well-formedness]
  (rust-lang/rust#115538)
- [Rework `impl Trait` lifetime inference]
  (rust-lang/rust#116891)
- [Change inductive trait solver cycles to be ambiguous]
  (rust-lang/rust#122791)

Compiler
--------
- [Define `-C strip` to only affect binaries, not artifacts like `.pdb`.]
  (rust-lang/rust#115120)
- [Stabilize `-Crelro-level` for controlling runtime link hardening.]
  (rust-lang/rust#121694)
- [Stabilize checking of `cfg` names and values at compile-time
  with `--check-cfg`.]
  (rust-lang/rust#123501)
  *Note that this only stabilizes the compiler part, the Cargo part
  is still unstable in this release.*
- [Add `aarch64-apple-visionos` and `aarch64-apple-visionos-sim`
  tier 3 targets.]
  (rust-lang/rust#121419)
- [Add `riscv32ima-unknown-none-elf` tier 3 target.]
  (rust-lang/rust#122696)
- [Promote several Windows targets to tier 2]
  (rust-lang/rust#121712):
  `aarch64-pc-windows-gnullvm`, `i686-pc-windows-gnullvm`, and
  `x86_64-pc-windows-gnullvm`.

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

Libraries
---------

- [Implement `FromIterator` for `(impl Default + Extend, impl
  Default + Extend)`.]
  (rust-lang/rust#107462)
- [Implement `{Div,Rem}Assign<NonZero<X>>` on `X`.]
  (rust-lang/rust#121952)
- [Document overrides of `clone_from()` in core/std.]
  (rust-lang/rust#122201)
- [Link MSVC default lib in core.]
  (rust-lang/rust#122268)
- [Caution against using `transmute` between pointers and integers.]
  (rust-lang/rust#122379)
- [Enable frame pointers for the standard library.]
  (rust-lang/rust#122646)

Stabilized APIs
---------------

- [`{integer}::unchecked_add`]
  (https://doc.rust-lang.org/stable/core/primitive.i32.html#method.unchecked_add)
- [`{integer}::unchecked_mul`]
  (https://doc.rust-lang.org/stable/core/primitive.i32.html#method.unchecked_mul)
- [`{integer}::unchecked_sub`]
  (https://doc.rust-lang.org/stable/core/primitive.i32.html#method.unchecked_sub)
- [`<[T]>::split_at_unchecked`]
  (https://doc.rust-lang.org/stable/core/primitive.slice.html#method.split_at_unchecked)
- [`<[T]>::split_at_mut_unchecked`]
  (https://doc.rust-lang.org/stable/core/primitive.slice.html#method.split_at_mut_unchecked)
- [`<[u8]>::utf8_chunks`]
  (https://doc.rust-lang.org/stable/core/primitive.slice.html#method.utf8_chunks)
- [`str::Utf8Chunks`]
  (https://doc.rust-lang.org/stable/core/str/struct.Utf8Chunks.html)
- [`str::Utf8Chunk`]
  (https://doc.rust-lang.org/stable/core/str/struct.Utf8Chunk.html)
- [`<*const T>::is_aligned`]
  (https://doc.rust-lang.org/stable/core/primitive.pointer.html#method.is_aligned)
- [`<*mut T>::is_aligned`]
  (https://doc.rust-lang.org/stable/core/primitive.pointer.html#method.is_aligned-1)
- [`NonNull::is_aligned`]
  (https://doc.rust-lang.org/stable/core/ptr/struct.NonNull.html#method.is_aligned)
- [`<*const [T]>::len`]
  (https://doc.rust-lang.org/stable/core/primitive.pointer.html#method.len)
- [`<*mut [T]>::len`]
  (https://doc.rust-lang.org/stable/core/primitive.pointer.html#method.len-1)
- [`<*const [T]>::is_empty`]
  (https://doc.rust-lang.org/stable/core/primitive.pointer.html#method.is_empty)
- [`<*mut [T]>::is_empty`]
  (https://doc.rust-lang.org/stable/core/primitive.pointer.html#method.is_empty-1)
- [`NonNull::<[T]>::is_empty`]
  (https://doc.rust-lang.org/stable/core/ptr/struct.NonNull.html#method.is_empty)
- [`CStr::count_bytes`]
  (https://doc.rust-lang.org/stable/core/ffi/c_str/struct.CStr.html#method.count_bytes)
- [`io::Error::downcast`]
  (https://doc.rust-lang.org/stable/std/io/struct.Error.html#method.downcast)
- [`num::NonZero<T>`]
  (https://doc.rust-lang.org/stable/core/num/struct.NonZero.html)
- [`path::absolute`]
  (https://doc.rust-lang.org/stable/std/path/fn.absolute.html)
- [`proc_macro::Literal::byte_character`]
  (https://doc.rust-lang.org/stable/proc_macro/struct.Literal.html#method.byte_character)
- [`proc_macro::Literal::c_string`]
  (https://doc.rust-lang.org/stable/proc_macro/struct.Literal.html#method.c_string)

These APIs are now stable in const contexts:

- [`Atomic*::into_inner`]
  (https://doc.rust-lang.org/stable/core/sync/atomic/struct.AtomicUsize.html#method.into_inner)
- [`io::Cursor::new`]
  (https://doc.rust-lang.org/stable/std/io/struct.Cursor.html#method.new)
- [`io::Cursor::get_ref`]
  (https://doc.rust-lang.org/stable/std/io/struct.Cursor.html#method.get_ref)
- [`io::Cursor::position`]
  (https://doc.rust-lang.org/stable/std/io/struct.Cursor.html#method.position)
- [`io::empty`]
  (https://doc.rust-lang.org/stable/std/io/fn.empty.html)
- [`io::repeat`]
  (https://doc.rust-lang.org/stable/std/io/fn.repeat.html)
- [`io::sink`]
  (https://doc.rust-lang.org/stable/std/io/fn.sink.html)
- [`panic::Location::caller`]
  (https://doc.rust-lang.org/stable/std/panic/struct.Location.html#method.caller)
- [`panic::Location::file`]
  (https://doc.rust-lang.org/stable/std/panic/struct.Location.html#method.file)
- [`panic::Location::line`]
  (https://doc.rust-lang.org/stable/std/panic/struct.Location.html#method.line)
- [`panic::Location::column`]
  (https://doc.rust-lang.org/stable/std/panic/struct.Location.html#method.column)

Cargo
-----

- [Prevent dashes in `lib.name`, always normalizing to `_`.]
  (rust-lang/cargo#12783)
- [Stabilize MSRV-aware version requirement selection in `cargo add`.]
  (rust-lang/cargo#13608)
- [Switch to using `gitoxide` by default for listing files.]
  (rust-lang/cargo#13696)

Rustdoc
-----

- [Always display stability version even if it's the same as the
  containing item.]
  (rust-lang/rust#118441)
- [Show a single search result for items with multiple paths.]
  (rust-lang/rust#119912)
- [Support typing `/` in docs to begin a search.]
  (rust-lang/rust#123355)

Misc
----

Compatibility Notes
-------------------

- [Update the minimum external LLVM to 17.]
  (rust-lang/rust#122649)
- [`RustcEncodable` and `RustcDecodable` are soft-destabilized, to
  be removed from the prelude in next edition.]
  (rust-lang/rust#116016)
- [The `wasm_c_abi` future-incompatibility lint will warn about use of the
  non-spec-compliant C ABI.]
  (rust-lang/rust#117918)
  Use `wasm-bindgen v0.2.88` to generate forward-compatible bindings.
- [Check return types of function types for well-formedness]
  (rust-lang/rust#115538)

Version 1.78.0 (2024-05-02)
===========================

Language
--------
- [Stabilize `#[cfg(target_abi = ...)]`]
  (rust-lang/rust#119590)
- [Stabilize the `#[diagnostic]` namespace and
  `#[diagnostic::on_unimplemented]` attribute]
  (rust-lang/rust#119888)
- [Make async-fn-in-trait implementable with concrete signatures]
  (rust-lang/rust#120103)
- [Make matching on NaN a hard error, and remove the rest of
  `illegal_floating_point_literal_pattern`]
  (rust-lang/rust#116284)
- [static mut: allow mutable reference to arbitrary types, not just
  slices and arrays]
  (rust-lang/rust#117614)
- [Extend `invalid_reference_casting` to include references casting
  to bigger memory layout]
  (rust-lang/rust#118983)
- [Add `non_contiguous_range_endpoints` lint for singleton gaps
  after exclusive ranges]
  (rust-lang/rust#118879)
- [Add `wasm_c_abi` lint for use of older wasm-bindgen versions]
  (rust-lang/rust#117918)
  This lint currently only works when using Cargo.
- [Update `indirect_structural_match` and `pointer_structural_match`
  lints to match RFC]
  (rust-lang/rust#120423)
- [Make non-`PartialEq`-typed consts as patterns a hard error]
  (rust-lang/rust#120805)
- [Split `refining_impl_trait` lint into `_reachable`, `_internal` variants]
  (rust-lang/rust#121720)
- [Remove unnecessary type inference when using associated types
  inside of higher ranked `where`-bounds]
  (rust-lang/rust#119849)
- [Weaken eager detection of cyclic types during type inference]
  (rust-lang/rust#119989)
- [`trait Trait: Auto {}`: allow upcasting from `dyn Trait` to `dyn Auto`]
  (rust-lang/rust#119338)

Compiler
--------

- [Made `INVALID_DOC_ATTRIBUTES` lint deny by default]
  (rust-lang/rust#111505)
- [Increase accuracy of redundant `use` checking]
  (rust-lang/rust#117772)
- [Suggest moving definition if non-found macro_rules! is defined later]
  (rust-lang/rust#121130)
- [Lower transmutes from int to pointer type as gep on null]
  (rust-lang/rust#121282)

Target changes:

- [Windows tier 1 targets now require at least Windows 10]
  (rust-lang/rust#115141)
 - [Enable CMPXCHG16B, SSE3, SAHF/LAHF and 128-bit Atomics in tier 1 Windows]
  (rust-lang/rust#120820)
- [Add `wasm32-wasip1` tier 2 (without host tools) target]
  (rust-lang/rust#120468)
- [Add `wasm32-wasip2` tier 3 target]
  (rust-lang/rust#119616)
- [Rename `wasm32-wasi-preview1-threads` to `wasm32-wasip1-threads`]
  (rust-lang/rust#122170)
- [Add `arm64ec-pc-windows-msvc` tier 3 target]
  (rust-lang/rust#119199)
- [Add `armv8r-none-eabihf` tier 3 target for the Cortex-R52]
  (rust-lang/rust#110482)
- [Add `loongarch64-unknown-linux-musl` tier 3 target]
  (rust-lang/rust#121832)

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

Libraries
---------

- [Bump Unicode to version 15.1.0, regenerate tables]
  (rust-lang/rust#120777)
- [Make align_offset, align_to well-behaved in all cases]
  (rust-lang/rust#121201)
- [PartialEq, PartialOrd: document expectations for transitive chains]
  (rust-lang/rust#115386)
- [Optimize away poison guards when std is built with panic=abort]
  (rust-lang/rust#100603)
- [Replace pthread `RwLock` with custom implementation]
  (rust-lang/rust#110211)
- [Implement unwind safety for Condvar on all platforms]
  (rust-lang/rust#121768)
- [Add ASCII fast-path for `char::is_grapheme_extended`]
  (rust-lang/rust#121138)

Stabilized APIs
---------------

- [`impl Read for &Stdin`]
  (https://doc.rust-lang.org/stable/std/io/struct.Stdin.html#impl-Read-for-%26Stdin)
- [Accept non `'static` lifetimes for several `std::error::Error`
  related implementations] (rust-lang/rust#113833)
- [Make `impl<Fd: AsFd>` impl take `?Sized`]
  (rust-lang/rust#114655)
- [`impl From<TryReserveError> for io::Error`]
  (https://doc.rust-lang.org/stable/std/io/struct.Error.html#impl-From%3CTryReserveError%3E-for-Error)

These APIs are now stable in const contexts:

- [`Barrier::new()`]
  (https://doc.rust-lang.org/stable/std/sync/struct.Barrier.html#method.new)

Cargo
-----

- [Stabilize lockfile v4](rust-lang/cargo#12852)
- [Respect `rust-version` when generating lockfile]
  (rust-lang/cargo#12861)
- [Control `--charset` via auto-detecting config value]
  (rust-lang/cargo#13337)
- [Support `target.<triple>.rustdocflags` officially]
  (rust-lang/cargo#13197)
- [Stabilize global cache data tracking]
  (rust-lang/cargo#13492)

Misc
----

- [rustdoc: add `--test-builder-wrapper` arg to support wrappers
  such as RUSTC_WRAPPER when building doctests]
  (rust-lang/rust#114651)

Compatibility Notes
-------------------

- [Many unsafe precondition checks now run for user code with debug
  assertions enabled] (rust-lang/rust#120594)
  This change helps users catch undefined behavior in their code,
  though the details of how much is checked are generally not
  stable.
- [riscv only supports split_debuginfo=off for now]
  (rust-lang/rust#120518)
- [Consistently check bounds on hidden types of `impl Trait`]
  (rust-lang/rust#121679)
- [Change equality of higher ranked types to not rely on subtyping]
  (rust-lang/rust#118247)
- [When called, additionally check bounds on normalized function return type]
  (rust-lang/rust#118882)
- [Expand coverage for `arithmetic_overflow` lint]
  (rust-lang/rust#119432)

Internal Changes
----------------

These changes do not affect any public interfaces of Rust, but they represent
significant improvements to the performance or internals of rustc and related
tools.

- [Update to LLVM 18](rust-lang/rust#120055)
- [Build `rustc` with 1CGU on `x86_64-pc-windows-msvc`]
  (rust-lang/rust#112267)
- [Build `rustc` with 1CGU on `x86_64-apple-darwin`]
  (rust-lang/rust#112268)
- [Introduce `run-make` V2 infrastructure, a `run_make_support`
  library and port over 2 tests as example]
  (rust-lang/rust#113026)
- [Windows: Implement condvar, mutex and rwlock using futex]
  (rust-lang/rust#121956)


Version 1.77.0 (2024-03-21)
==========================

- [Reveal opaque types within the defining body for exhaustiveness checking.]
  (rust-lang/rust#116821)
- [Stabilize C-string literals.]
  (rust-lang/rust#117472)
- [Stabilize THIR unsafeck.]
  (rust-lang/rust#117673)
- [Add lint `static_mut_refs` to warn on references to mutable statics.]
  (rust-lang/rust#117556)
- [Support async recursive calls (as long as they have indirection).]
  (rust-lang/rust#117703)
- [Undeprecate lint `unstable_features` and make use of it in the compiler.]
  (rust-lang/rust#118639)
- [Make inductive cycles in coherence ambiguous always.]
  (rust-lang/rust#118649)
- [Get rid of type-driven traversal in const-eval interning]
  (rust-lang/rust#119044),
  only as a [future compatiblity lint]
  (rust-lang/rust#122204) for now.
- [Deny braced macro invocations in let-else.]
  (rust-lang/rust#119062)

Compiler
--------

- [Include lint `soft_unstable` in future breakage reports.]
  (rust-lang/rust#116274)
- [Make `i128` and `u128` 16-byte aligned on x86-based targets.]
  (rust-lang/rust#116672)
- [Use `--verbose` in diagnostic output.]
  (rust-lang/rust#119129)
- [Improve spacing between printed tokens.]
  (rust-lang/rust#120227)
- [Merge the `unused_tuple_struct_fields` lint into `dead_code`.]
  (rust-lang/rust#118297)
- [Error on incorrect implied bounds in well-formedness check]
  (rust-lang/rust#118553),
  with a temporary exception for Bevy.
- [Fix coverage instrumentation/reports for non-ASCII source code.]
  (rust-lang/rust#119033)
- [Fix `fn`/`const` items implied bounds and well-formedness check.]
  (rust-lang/rust#120019)
- [Promote `riscv32{im|imafc}-unknown-none-elf` targets to tier 2.]
  (rust-lang/rust#118704)
- Add several new tier 3 targets:
  - [`aarch64-unknown-illumos`]
    (rust-lang/rust#112936)
  - [`hexagon-unknown-none-elf`]
    (rust-lang/rust#117601)
  - [`riscv32imafc-esp-espidf`]
    (rust-lang/rust#119738)
  - [`riscv32im-risc0-zkvm-elf`]
    (rust-lang/rust#117958)

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

Libraries
---------

- [Implement `From<&[T; N]>` for `Cow<[T]>`.]
  (rust-lang/rust#113489)
- [Remove special-case handling of `vec.split_off
  (0)`.](rust-lang/rust#119917)

Stabilized APIs
---------------

- [`array::each_ref`]
  (https://doc.rust-lang.org/stable/std/primitive.array.html#method.each_ref)
- [`array::each_mut`]
  (https://doc.rust-lang.org/stable/std/primitive.array.html#method.each_mut)
- [`core::net`]
  (https://doc.rust-lang.org/stable/core/net/index.html)
- [`f32::round_ties_even`]
  (https://doc.rust-lang.org/stable/std/primitive.f32.html#method.round_ties_even)
- [`f64::round_ties_even`]
  (https://doc.rust-lang.org/stable/std/primitive.f64.html#method.round_ties_even)
- [`mem::offset_of!`]
  (https://doc.rust-lang.org/stable/std/mem/macro.offset_of.html)
- [`slice::first_chunk`]
  (https://doc.rust-lang.org/stable/std/primitive.slice.html#method.first_chunk)
- [`slice::first_chunk_mut`]
  (https://doc.rust-lang.org/stable/std/primitive.slice.html#method.first_chunk_mut)
- [`slice::split_first_chunk`]
  (https://doc.rust-lang.org/stable/std/primitive.slice.html#method.split_first_chunk)
- [`slice::split_first_chunk_mut`]
  (https://doc.rust-lang.org/stable/std/primitive.slice.html#method.split_first_chunk_mut)
- [`slice::last_chunk`]
  (https://doc.rust-lang.org/stable/std/primitive.slice.html#method.last_chunk)
- [`slice::last_chunk_mut`]
  (https://doc.rust-lang.org/stable/std/primitive.slice.html#method.last_chunk_mut)
- [`slice::split_last_chunk`]
  (https://doc.rust-lang.org/stable/std/primitive.slice.html#method.split_last_chunk)
- [`slice::split_last_chunk_mut`]
  (https://doc.rust-lang.org/stable/std/primitive.slice.html#method.split_last_chunk_mut)
- [`slice::chunk_by`]
  (https://doc.rust-lang.org/stable/std/primitive.slice.html#method.chunk_by)
- [`slice::chunk_by_mut`]
  (https://doc.rust-lang.org/stable/std/primitive.slice.html#method.chunk_by_mut)
- [`Bound::map`]
  (https://doc.rust-lang.org/stable/std/ops/enum.Bound.html#method.map)
- [`File::create_new`]
  (https://doc.rust-lang.org/stable/std/fs/struct.File.html#method.create_new)
- [`Mutex::clear_poison`]
  (https://doc.rust-lang.org/stable/std/sync/struct.Mutex.html#method.clear_poison)
- [`RwLock::clear_poison`]
  (https://doc.rust-lang.org/stable/std/sync/struct.RwLock.html#method.clear_poison)

Cargo
-----

- [Extend the build directive syntax with `cargo::`.]
  (rust-lang/cargo#12201)
- [Stabilize metadata `id` format as `PackageIDSpec`.]
  (rust-lang/cargo#12914)
- [Pull out as `cargo-util-schemas` as a crate.]
  (rust-lang/cargo#13178)
- [Strip all debuginfo when debuginfo is not requested.]
  (rust-lang/cargo#13257)
- [Inherit jobserver from env for all kinds of runners.]
  (rust-lang/cargo#12776)
- [Deprecate rustc plugin support in cargo.]
  (rust-lang/cargo#13248)

Rustdoc
-----

- [Allows links in markdown headings.]
  (rust-lang/rust#117662)
- [Search for tuples and unit by type with `()`.]
  (rust-lang/rust#118194)
- [Clean up the source sidebar's hide button.]
  (rust-lang/rust#119066)
- [Prevent JS injection from `localStorage`.]
  (rust-lang/rust#120250)

Misc
----

- [Recommend version-sorting for all sorting in style guide.]
  (rust-lang/rust#115046)

Internal Changes
----------------

These changes do not affect any public interfaces of Rust, but they represent
significant improvements to the performance or internals of rustc and related
tools.

- [Add more weirdness to `weird-exprs.rs`.]
  (rust-lang/rust#119028)
github-merge-queue bot pushed a commit that referenced this pull request Apr 27, 2025
This proposes to stabilize automatic garbage collection of Cargo's
global cache data in the cargo home directory.

### What is being stabilized?

This PR stabilizes automatic garbage collection, which is triggered at
most once per day by default. This automatic gc will delete old, unused
files in cargo's home directory.

It will delete files that need to be downloaded from the network after 3
months, and files that can be generated without network access after 1
month. These thresholds are intended to balance the intent of reducing
cargo's disk usage versus deleting too often forcing cargo to do extra
work when files are missing.

Tracking of the last-use data is stored in a sqlite database in the
cargo home directory. Cargo updates timestamps in that database whenever
it accesses a file in the cache. This part is already stabilized.

This PR also stabilizes the `gc.auto.frequency` configuration option.
The primary use case for when a user may want to set that is to set it
to "never" to disable gc should the need arise to avoid it.

When gc is initiated, and there are files to delete, there will be a
progress bar while it is deleting them. The progress bar will disappear
when it finishes. If the user runs with `-v` verbose option, then cargo
will also display which files it deletes.

If there is an error while cleaning, cargo will only display a warning,
and otherwise continue.

### What is not being stabilized?

The manual garbage collection option (via `cargo clean gc`) is not
proposed to be stabilized at this time. That still needs some design
work. This is tracked in
#13060.

Additionally, there are several low-level config options currently
implemented which define the thresholds for when it will delete files. I
think these options are probably too low-level and specific. This is
tracked in #13061.

Garbage collection of build artifacts is not yet implemented, and
tracked in #13136.

### Background

This feature is tracked in
#12633 and was implemented in a
variety of PRs, primarily #12634.

The tests for this feature are located in
https://github.com/rust-lang/cargo/blob/master/tests/testsuite/global_cache_tracker.rs.

Cargo started tracking the last-use data on stable via
#13492 in 1.78 which was released
2024-05-02. This PR is proposing to stabilize automatic deletion in 1.82
which will be released in 2024-10-17.

### Risks

Users who frequently use versions of Rust older than 1.78 will not have
the last-use data tracking updated. If they infrequently use 1.78 or
newer, and use the same cache files, then the last-use tracking will
only be updated by the newer versions. If that time frame is more than 1
month (or 3 months for downloaded data), then cargo will delete files
that the older versions are still using. This means the next time they
run the older version, it will have to re-download or re-extract the
files.

The effects of deleting cache data in environments where cargo's cache
is modified by external tools is not fully known. For example, CI
caching systems may save and restore cargo's cache. Similarly, things
like Docker images that try to save the cache in a layer, or mount the
cache in a read-only filesystem may have undesirable interactions.

The once-a-day performance hit might be noticeable to some people. I've
been using this for several months, and almost never notice it. However,
slower systems, or situations where there is a lot of data to delete
might take a while (on the order of seconds hopefully).
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