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debuginfo: Stabilize -Z debug-macros, -Z collapse-macro-debuginfo and #[collapse_debuginfo] #120845

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merged 2 commits into from
Apr 26, 2024

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@petrochenkov petrochenkov commented Feb 9, 2024

-Z debug-macros is "stabilized" by enabling it by default and removing.

-Z collapse-macro-debuginfo is stabilized as -C collapse-macro-debuginfo.
It now supports all typical boolean values (parse_opt_bool) in addition to just yes/no.

Default value of collapse_debuginfo was changed from false to external (i.e. collapsed if external, not collapsed if local) - #100758 (comment) describes some debugging scenarios that motivate this default as reasonable.
#[collapse_debuginfo] attribute without a value is no longer supported to avoid guessing the default.

Stabilization report: #120845 (comment)

Closes #100758
Closes #41743
Closes #39153

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rustbot commented Feb 9, 2024

r? @oli-obk

rustbot has assigned @oli-obk.
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 S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. T-compiler Relevant to the compiler team, which will review and decide on the PR/issue. labels Feb 9, 2024
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rustbot commented Feb 9, 2024

Some changes occurred in compiler/rustc_codegen_cranelift

cc @bjorn3

The Miri subtree was changed

cc @rust-lang/miri

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cc @davidtwco @azhogin

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@oli-obk oli-obk added the needs-fcp This change is insta-stable, so needs a completed FCP to proceed. label Feb 9, 2024
@petrochenkov petrochenkov added S-waiting-on-author Status: This is awaiting some action (such as code changes or more information) from the author. and removed S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. labels Feb 10, 2024
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I haven't thoroughly reviewed the changes here but this seems sensible to me at first glance.

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I removed one fast path optimization for simplicity, so let's also run benchmarks.
@bors try @rust-timer queue

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@rustbot rustbot added the S-waiting-on-perf Status: Waiting on a perf run to be completed. label Feb 12, 2024
bors added a commit to rust-lang-ci/rust that referenced this pull request Feb 12, 2024
debuginfo: Stabilize `-Z debug-macros`, `-Z collapse-macro-debuginfo` and `#[collapse_debuginfo]`

`-Z debug-macros` is "stabilized" by enabling it by default and removing.

`-Z collapse-macro-debuginfo` is stabilized as `-C collapse-macro-debuginfo`.
It now supports all typical boolean values (`parse_opt_bool`) in addition to just yes/no.

Default value of `collapse_debuginfo` was changed from `false` to `external` (i.e. collapsed if external, not collapsed if local) - rust-lang#100758 (comment) describes some debugging scenarios that motivate this default as reasonable.
`#[collapse_debuginfo]` attribute without a value is no longer supported to avoid guessing the default.

Closes rust-lang#100758
Closes rust-lang#41743
Closes rust-lang#39153

TODO: Stabilization report
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bors commented Feb 12, 2024

⌛ Trying commit 78ee1bc with merge 575a7f3...

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bors commented Feb 12, 2024

☀️ Try build successful - checks-actions
Build commit: 575a7f3 (575a7f35a80ab18d54b08775b7bd6cc50ee4e338)

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Finished benchmarking commit (575a7f3): comparison URL.

Overall result: ❌✅ regressions and improvements - no action needed

Benchmarking this pull request likely means that it is perf-sensitive, so we're automatically marking it as not fit for rolling up. While you can manually mark this PR as fit for rollup, we strongly recommend not doing so since this PR may lead to changes in compiler perf.

@bors rollup=never
@rustbot label: -S-waiting-on-perf -perf-regression

Instruction count

This is a highly reliable metric that was used to determine the overall result at the top of this comment.

mean range count
Regressions ❌
(primary)
0.4% [0.4%, 0.4%] 1
Regressions ❌
(secondary)
- - 0
Improvements ✅
(primary)
- - 0
Improvements ✅
(secondary)
-0.6% [-0.7%, -0.5%] 2
All ❌✅ (primary) 0.4% [0.4%, 0.4%] 1

Max RSS (memory usage)

Results

This is a less reliable metric that may be of interest but was not used to determine the overall result at the top of this comment.

mean range count
Regressions ❌
(primary)
- - 0
Regressions ❌
(secondary)
- - 0
Improvements ✅
(primary)
-2.4% [-2.4%, -2.4%] 1
Improvements ✅
(secondary)
-2.8% [-3.2%, -2.3%] 7
All ❌✅ (primary) -2.4% [-2.4%, -2.4%] 1

Cycles

This benchmark run did not return any relevant results for this metric.

Binary size

Results

This is a less reliable metric that may be of interest but was not used to determine the overall result at the top of this comment.

mean range count
Regressions ❌
(primary)
0.0% [0.0%, 0.1%] 40
Regressions ❌
(secondary)
0.0% [0.0%, 0.1%] 6
Improvements ✅
(primary)
- - 0
Improvements ✅
(secondary)
- - 0
All ❌✅ (primary) 0.0% [0.0%, 0.1%] 40

Bootstrap: 663.718s -> 664.389s (0.10%)
Artifact size: 308.26 MiB -> 308.31 MiB (0.01%)

@rustbot rustbot removed the S-waiting-on-perf Status: Waiting on a perf run to be completed. label Feb 12, 2024
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Perf changes are noise.
@bors rollup=maybe

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petrochenkov commented Feb 12, 2024

Stabilization Report

Before this PR all spans coming from macro definitions were by default collapsed to a single span representing the macro's call site when generating debuginfo.
The option -Z debug-macros changed that behavior and preserved all spans in debuginfo without collapsing.

With this PR the -Z debug-macros option is removed and the defaults are partially swapped.
By default spans are preserved without collapsing, giving more detailed information during debugging, but only for macros coming from the current crate.
For macros from other crates the spans are still collapsed to a single call site span, this way we don't jump to code of println! and other macros from the standard library.

Attributes #[collapse_debuginfo(yes/no/external)] and command line options -C collapse-macro-debuginfo=yes/no/external (replace -Z debug-macros) provide more fine-grained control over collapsing debuginfo spans to call site, when the defaults are insufficient.

History

#41743 identified the problem with detailed debuginfo spans for macros not being available on stable channel.

rust-lang/rfcs#2117 and rust-lang/compiler-team#386 provided the solution for undesirable jumping to sources of println! and friends when detailed spans are enabled.
#99556 implemented that solution in July 2022.

#118903 added detailed tests for the feature and fixed some issues with nested macro calls in December 2023.
#119828 added some more fine grained options to the #[collapse_debuginfo] attribute, and added a command line flag -C collapse-macro-debuginfo for overriding both defaults and attributes as well in January 2024.

Design

rust-lang/compiler-team#386 gives motivation for not collapsing macros in debuginfo in general, but collapsing some macros in particular.

Comments in #100758 (comment) and below describe some possible debugging scenarios, and make a choice for the default collapsing behavior implemented in this PR.

Tests

  • tests/debuginfo/collapse-debuginfo*
  • tests/debuginfo/skip_second_statement*
  • tests/debuginfo/lexical-scope-with-macro.rs

Documentation

src/doc/rustc/src/codegen-options/index.md in this PR and rust-lang/reference#1468 in the reference.

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@rfcbot fcp merge

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rfcbot commented Feb 12, 2024

Team member @petrochenkov 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!

cc @rust-lang/lang-advisors: FCP proposed for lang, please feel free to register concerns.
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. labels Feb 12, 2024
@petrochenkov petrochenkov added S-waiting-on-team Status: Awaiting decision from the relevant subteam (see the T-<team> label). I-compiler-nominated Nominated for discussion during a compiler team meeting. and removed S-waiting-on-author Status: This is awaiting some action (such as code changes or more information) from the author. needs-fcp This change is insta-stable, so needs a completed FCP to proceed. labels Feb 12, 2024
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bors commented Apr 25, 2024

📌 Commit 98804c1 has been approved by oli-obk

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-author Status: This is awaiting some action (such as code changes or more information) from the author. labels Apr 25, 2024
bors added a commit to rust-lang-ci/rust that referenced this pull request Apr 25, 2024
debuginfo: Stabilize `-Z debug-macros`, `-Z collapse-macro-debuginfo` and `#[collapse_debuginfo]`

`-Z debug-macros` is "stabilized" by enabling it by default and removing.

`-Z collapse-macro-debuginfo` is stabilized as `-C collapse-macro-debuginfo`.
It now supports all typical boolean values (`parse_opt_bool`) in addition to just yes/no.

Default value of `collapse_debuginfo` was changed from `false` to `external` (i.e. collapsed if external, not collapsed if local) - rust-lang#100758 (comment) describes some debugging scenarios that motivate this default as reasonable.
`#[collapse_debuginfo]` attribute without a value is no longer supported to avoid guessing the default.

Stabilization report: rust-lang#120845 (comment)

Closes rust-lang#100758
Closes rust-lang#41743
Closes rust-lang#39153
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bors commented Apr 25, 2024

⌛ Testing commit 98804c1 with merge 78aad13...

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@bors bors added S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. and removed S-waiting-on-bors Status: Waiting on bors to run and complete tests. Bors will change the label on completion. labels Apr 25, 2024
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@bors r=oli-obk

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bors commented Apr 26, 2024

📌 Commit 683ad6b has been approved by oli-obk

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 Apr 26, 2024
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bors commented Apr 26, 2024

⌛ Testing commit 683ad6b with merge 6acb9e7...

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bors commented Apr 26, 2024

☀️ Test successful - checks-actions
Approved by: oli-obk
Pushing 6acb9e7 to master...

@bors bors added the merged-by-bors This PR was explicitly merged by bors. label Apr 26, 2024
@bors bors merged commit 6acb9e7 into rust-lang:master Apr 26, 2024
11 checks passed
@rustbot rustbot added this to the 1.79.0 milestone Apr 26, 2024
github-actions bot pushed a commit to rust-lang/miri that referenced this pull request Apr 26, 2024
debuginfo: Stabilize `-Z debug-macros`, `-Z collapse-macro-debuginfo` and `#[collapse_debuginfo]`

`-Z debug-macros` is "stabilized" by enabling it by default and removing.

`-Z collapse-macro-debuginfo` is stabilized as `-C collapse-macro-debuginfo`.
It now supports all typical boolean values (`parse_opt_bool`) in addition to just yes/no.

Default value of `collapse_debuginfo` was changed from `false` to `external` (i.e. collapsed if external, not collapsed if local) - rust-lang/rust#100758 (comment) describes some debugging scenarios that motivate this default as reasonable.
`#[collapse_debuginfo]` attribute without a value is no longer supported to avoid guessing the default.

Stabilization report: rust-lang/rust#120845 (comment)

Closes rust-lang/rust#100758
Closes rust-lang/rust#41743
Closes rust-lang/rust#39153
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Finished benchmarking commit (6acb9e7): comparison URL.

Overall result: no relevant changes - no action needed

@rustbot label: -perf-regression

Instruction count

This benchmark run did not return any relevant results for this metric.

Max RSS (memory usage)

Results

This is a less reliable metric that may be of interest but was not used to determine the overall result at the top of this comment.

mean range count
Regressions ❌
(primary)
- - 0
Regressions ❌
(secondary)
3.4% [3.4%, 3.4%] 1
Improvements ✅
(primary)
- - 0
Improvements ✅
(secondary)
- - 0
All ❌✅ (primary) - - 0

Cycles

Results

This is a less reliable metric that may be of interest but was not used to determine the overall result at the top of this comment.

mean range count
Regressions ❌
(primary)
1.0% [1.0%, 1.0%] 1
Regressions ❌
(secondary)
- - 0
Improvements ✅
(primary)
- - 0
Improvements ✅
(secondary)
- - 0
All ❌✅ (primary) 1.0% [1.0%, 1.0%] 1

Binary size

Results

This is a less reliable metric that may be of interest but was not used to determine the overall result at the top of this comment.

mean range count
Regressions ❌
(primary)
0.1% [0.0%, 1.0%] 54
Regressions ❌
(secondary)
0.0% [0.0%, 0.1%] 7
Improvements ✅
(primary)
- - 0
Improvements ✅
(secondary)
- - 0
All ❌✅ (primary) 0.1% [0.0%, 1.0%] 54

Bootstrap: 670.868s -> 670.073s (-0.12%)
Artifact size: 316.00 MiB -> 316.00 MiB (-0.00%)

@ehuss ehuss added the relnotes Marks issues that should be documented in the release notes of the next release. label Apr 27, 2024
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philipc commented May 3, 2024

This has broken a test in backtrace (rust-lang/backtrace-rs#617). The collapse_debuginfo attribute can be used to fix it.

The debuginfo for line 11 is now line 11 instead of the caller, as expected. However, the result of the line! (called via pos!) is still the caller. Is it intentional that line! is unaffected? It's not clear cut to me how this should work, so I want to check.

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@philipc
Test suite in this repo has the same test - tests/ui/debuginfo/backtrace-dylib-dep.rs, I updated it to preserve the previous behavior.
The test relied on specific lines being emitted into debuginfo, and since we are changing the debuginfo emitted by default behavior of such tests may also change.

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petrochenkov commented May 3, 2024

file!() and line!() are not defined in the current crate, so they are collapsed by default now, unlike pos!() and check!() defined in the current crate.

UPD: As for values returned by file!() and line!(), they follow their own logic independent from debuginfo (defined in compiler\rustc_builtin_macros\src\source_util.rs). They traverse the macro call stack until they encounter root expansion or include! and report the line/column/file at that position.

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Breaking the test was fine if it can still be configured to pass. I'm glad that we moved that test into rustc's suite, so that it can be kept current with current defaults. I'm not sure that I want to remove the copy of the test from the backtrace suite yet, but I can just copy petrochenkov's changes to fix it.

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)
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