Skip to content
New issue

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

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

Already on GitHub? Sign in to your account

coverage: Extract hole spans from HIR instead of MIR #127199

Merged
merged 2 commits into from
Jul 8, 2024

Conversation

Zalathar
Copy link
Contributor

@Zalathar Zalathar commented Jul 1, 2024

This makes it possible to treat more kinds of nested item/code as holes, instead of being restricted to closures.

(It also potentially opens up the possibility of using HIR holes to modify branch or MC/DC spans, though we currently don't actually do this.)

Thus, this new implementation treats the following as holes:

  • Closures (as before, including async and coroutines)
  • All nested items
  • Inline const (because why not)

This gives more accurate coverage reports, because lines occupied by holes don't show the execution count from the enclosing function.

Fixes #126626.


Representative example of the improved coverage instrumentation for functions containing nested items.

@rustbot
Copy link
Collaborator

rustbot commented Jul 1, 2024

r? @matthewjasper

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

Use r? to explicitly pick a reviewer

@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 Jul 1, 2024
@rustbot
Copy link
Collaborator

rustbot commented Jul 1, 2024

Some changes occurred to MIR optimizations

cc @rust-lang/wg-mir-opt

@rustbot rustbot added the A-code-coverage Area: Source-based code coverage (-Cinstrument-coverage) label Jul 1, 2024
@Zalathar Zalathar force-pushed the hir-holes branch 2 times, most recently from c5fbc36 to 6846565 Compare July 6, 2024 12:18
This makes it possible to treat more kinds of nested item/code as holes,
instead of being restricted to closures.
@Zalathar
Copy link
Contributor Author

Zalathar commented Jul 8, 2024

Added some comments as requested (diff).

@oli-obk
Copy link
Contributor

oli-obk commented Jul 8, 2024

bors r plus

@bors
Copy link
Contributor

bors commented Jul 8, 2024

📌 Commit 63c04f0 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 Jul 8, 2024
@bors
Copy link
Contributor

bors commented Jul 8, 2024

⌛ Testing commit 63c04f0 with merge cfd7cf5...

@bors
Copy link
Contributor

bors commented Jul 8, 2024

☀️ Test successful - checks-actions
Approved by: oli-obk
Pushing cfd7cf5 to master...

@bors bors added the merged-by-bors This PR was explicitly merged by bors. label Jul 8, 2024
@bors bors merged commit cfd7cf5 into rust-lang:master Jul 8, 2024
7 checks passed
@rustbot rustbot added this to the 1.81.0 milestone Jul 8, 2024
@rust-timer
Copy link
Collaborator

Finished benchmarking commit (cfd7cf5): 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)

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

Cycles

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

Binary size

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

Bootstrap: 701.456s -> 701.941s (0.07%)
Artifact size: 328.71 MiB -> 328.61 MiB (-0.03%)

@Zalathar Zalathar deleted the hir-holes branch July 9, 2024 01:09
@Zalathar
Copy link
Contributor Author

@rustbot label +relnotes

Nominating for release notes (compiler), as a user-visible improvement.

Suggested summary:

Improve coverage instrumentation for functions containing nested items

@rustbot rustbot added the relnotes Marks issues that should be documented in the release notes of the next release. label Jul 11, 2024
tmeijn pushed a commit to tmeijn/dotfiles that referenced this pull request Sep 11, 2024
This MR contains the following updates:

| Package | Update | Change |
|---|---|---|
| [rust](https://github.com/rust-lang/rust) | minor | `1.80.1` -> `1.81.0` |

MR created with the help of [el-capitano/tools/renovate-bot](https://gitlab.com/el-capitano/tools/renovate-bot).

**Proposed changes to behavior should be submitted there as MRs.**

---

### Release Notes

<details>
<summary>rust-lang/rust (rust)</summary>

### [`v1.81.0`](https://github.com/rust-lang/rust/blob/HEAD/RELEASES.md#Version-1810-2024-09-05)

[Compare Source](rust-lang/rust@1.80.1...1.81.0)

\==========================

<a id="1.81.0-Language"></a>

## Language

-   [Abort on uncaught panics in `extern "C"` functions.](rust-lang/rust#116088)
-   [Fix ambiguous cases of multiple `&` in elided self lifetimes.](rust-lang/rust#117967)
-   [Stabilize `#[expect]` for lints (RFC 2383),](rust-lang/rust#120924) like `#[allow]` with a warning if the lint is *not* fulfilled.
-   [Change method resolution to constrain hidden types instead of rejecting method candidates.](rust-lang/rust#123962)
-   [Bump `elided_lifetimes_in_associated_constant` to deny.](rust-lang/rust#124211)
-   [`offset_from`: always allow pointers to point to the same address.](rust-lang/rust#124921)
-   [Allow constraining opaque types during subtyping in the trait system.](rust-lang/rust#125447)
-   [Allow constraining opaque types during various unsizing casts.](rust-lang/rust#125610)
-   [Deny keyword lifetimes pre-expansion.](rust-lang/rust#126762)

<a id="1.81.0-Compiler"></a>

## Compiler

-   [Make casts of pointers to trait objects stricter.](rust-lang/rust#120248)
-   [Check alias args for well-formedness even if they have escaping bound vars.](rust-lang/rust#123737)
-   [Deprecate no-op codegen option `-Cinline-threshold=...`.](rust-lang/rust#124712)
-   [Re-implement a type-size based limit.](rust-lang/rust#125507)
-   [Properly account for alignment in `transmute` size checks.](rust-lang/rust#125740)
-   [Remove the `box_pointers` lint.](rust-lang/rust#126018)
-   [Ensure the interpreter checks bool/char for validity when they are used in a cast.](rust-lang/rust#126265)
-   [Improve coverage instrumentation for functions containing nested items.](rust-lang/rust#127199)
-   Target changes:
    -   [Add Tier 3 `no_std` Xtensa targets:](rust-lang/rust#125141) `xtensa-esp32-none-elf`, `xtensa-esp32s2-none-elf`, `xtensa-esp32s3-none-elf`
    -   [Add Tier 3 `std` Xtensa targets:](rust-lang/rust#126380) `xtensa-esp32-espidf`, `xtensa-esp32s2-espidf`, `xtensa-esp32s3-espidf`
    -   [Add Tier 3 i686 Redox OS target:](rust-lang/rust#126192) `i686-unknown-redox`
    -   [Promote `arm64ec-pc-windows-msvc` to Tier 2.](rust-lang/rust#126039)
    -   [Promote `loongarch64-unknown-linux-musl` to Tier 2 with host tools.](rust-lang/rust#126298)
    -   [Enable full tools and profiler for LoongArch Linux targets.](rust-lang/rust#127078)
    -   [Unconditionally warn on usage of `wasm32-wasi`.](rust-lang/rust#126662) (see compatibility note below)
    -   Refer to Rust's \[platform support page]\[platform-support-doc] for more information on Rust's tiered platform support.

<a id="1.81.0-Libraries"></a>

## Libraries

-   [Split core's `PanicInfo` and std's `PanicInfo`.](rust-lang/rust#115974) (see compatibility note below)
-   [Generalize `{Rc,Arc}::make_mut()` to unsized types.](rust-lang/rust#116113)
-   [Replace sort implementations with stable `driftsort` and unstable `ipnsort`.](rust-lang/rust#124032) All `slice::sort*` and `slice::select_nth*` methods are expected to see significant performance improvements. See the [research project](https://github.com/Voultapher/sort-research-rs) for more details.
-   [Document behavior of `create_dir_all` with respect to empty paths.](rust-lang/rust#125112)
-   [Fix interleaved output in the default panic hook when multiple threads panic simultaneously.](rust-lang/rust#127397)

<a id="1.81.0-Stabilized-APIs"></a>

## Stabilized APIs

-   [`core::error`](https://doc.rust-lang.org/stable/core/error/index.html)
-   [`hint::assert_unchecked`](https://doc.rust-lang.org/stable/core/hint/fn.assert_unchecked.html)
-   [`fs::exists`](https://doc.rust-lang.org/stable/std/fs/fn.exists.html)
-   [`AtomicBool::fetch_not`](https://doc.rust-lang.org/stable/core/sync/atomic/struct.AtomicBool.html#method.fetch_not)
-   [`Duration::abs_diff`](https://doc.rust-lang.org/stable/core/time/struct.Duration.html#method.abs_diff)
-   [`IoSlice::advance`](https://doc.rust-lang.org/stable/std/io/struct.IoSlice.html#method.advance)
-   [`IoSlice::advance_slices`](https://doc.rust-lang.org/stable/std/io/struct.IoSlice.html#method.advance_slices)
-   [`IoSliceMut::advance`](https://doc.rust-lang.org/stable/std/io/struct.IoSliceMut.html#method.advance)
-   [`IoSliceMut::advance_slices`](https://doc.rust-lang.org/stable/std/io/struct.IoSliceMut.html#method.advance_slices)
-   [`PanicHookInfo`](https://doc.rust-lang.org/stable/std/panic/struct.PanicHookInfo.html)
-   [`PanicInfo::message`](https://doc.rust-lang.org/stable/core/panic/struct.PanicInfo.html#method.message)
-   [`PanicMessage`](https://doc.rust-lang.org/stable/core/panic/struct.PanicMessage.html)

These APIs are now stable in const contexts:

-   [`char::from_u32_unchecked`](https://doc.rust-lang.org/stable/core/char/fn.from_u32\_unchecked.html) (function)
-   [`char::from_u32_unchecked`](https://doc.rust-lang.org/stable/core/primitive.char.html#method.from_u32\_unchecked) (method)
-   [`CStr::count_bytes`](https://doc.rust-lang.org/stable/core/ffi/c_str/struct.CStr.html#method.count_bytes)
-   [`CStr::from_ptr`](https://doc.rust-lang.org/stable/core/ffi/c_str/struct.CStr.html#method.from_ptr)

<a id="1.81.0-Cargo"></a>

## Cargo

-   [Generated `.cargo_vcs_info.json` is always included, even when `--allow-dirty` is passed.](rust-lang/cargo#13960)
-   [Disallow `package.license-file` and `package.readme` pointing to non-existent files during packaging.](rust-lang/cargo#13921)
-   [Disallow passing `--release`/`--debug` flag along with the `--profile` flag.](rust-lang/cargo#13971)
-   [Remove `lib.plugin` key support in `Cargo.toml`. Rust plugin support has been deprecated for four years and was removed in 1.75.0.](rust-lang/cargo#13902)

<a id="1.81.0-Compatibility-Notes"></a>

## Compatibility Notes

-   Usage of the `wasm32-wasi` target will now issue a compiler warning and request users switch to the `wasm32-wasip1` target instead. Both targets are the same, `wasm32-wasi` is only being renamed, and this [change to the WASI target](https://blog.rust-lang.org/2024/04/09/updates-to-rusts-wasi-targets.html) is being done to enable removing `wasm32-wasi` in January 2025.

-   We have renamed `std::panic::PanicInfo` to `std::panic::PanicHookInfo`. The old name will continue to work as an alias, but will result in a deprecation warning starting in Rust 1.82.0.

    `core::panic::PanicInfo` will remain unchanged, however, as this is now a *different type*.

    The reason is that these types have different roles: `std::panic::PanicHookInfo` is the argument to the [panic hook](https://doc.rust-lang.org/stable/std/panic/fn.set_hook.html) in std context (where panics can have an arbitrary payload), while `core::panic::PanicInfo` is the argument to the [`#[panic_handler]`](https://doc.rust-lang.org/nomicon/panic-handler.html) in no_std context (where panics always carry a formatted *message*). Separating these types allows us to add more useful methods to these types, such as `std::panic::PanicHookInfo::payload_as_str()` and `core::panic::PanicInfo::message()`.

-   The new sort implementations may panic if a type's implementation of [`Ord`](https://doc.rust-lang.org/std/cmp/trait.Ord.html) (or the given comparison function) does not implement a [total order](https://en.wikipedia.org/wiki/Total_order) as the trait requires. `Ord`'s supertraits (`PartialOrd`, `Eq`, and `PartialEq`) must also be consistent. The previous implementations would not "notice" any problem, but the new implementations have a good chance of detecting inconsistencies, throwing a panic rather than returning knowingly unsorted data.

-   [In very rare cases, a change in the internal evaluation order of the trait
    solver may result in new fatal overflow errors.](rust-lang/rust#126128)

<a id="1.81.0-Internal-Changes"></a>

## 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 a Rust-for Linux `auto` CI job to check kernel builds.](rust-lang/rust#125209)

</details>

---

### Configuration

📅 **Schedule**: Branch creation - At any time (no schedule defined), Automerge - At any time (no schedule defined).

🚦 **Automerge**: Disabled by config. Please merge this manually once you are satisfied.

♻ **Rebasing**: Whenever MR becomes conflicted, or you tick the rebase/retry checkbox.

🔕 **Ignore**: Close this MR and you won't be reminded about this update again.

---

 - [ ] <!-- rebase-check -->If you want to rebase/retry this MR, check this box

---

This MR has been generated by [Renovate Bot](https://github.com/renovatebot/renovate).
<!--renovate-debug:eyJjcmVhdGVkSW5WZXIiOiIzNy40NDAuNyIsInVwZGF0ZWRJblZlciI6IjM3LjQ0MC43IiwidGFyZ2V0QnJhbmNoIjoibWFpbiIsImxhYmVscyI6WyJSZW5vdmF0ZSBCb3QiXX0=-->
wip-sync pushed a commit to NetBSD/pkgsrc-wip that referenced this pull request Sep 22, 2024
Pkgsrc changes:
 * Adapt patches, apply to new vendored crates where needed.
 * Back-port rust pull request 130110, "make dist vendoring configurable"
 * Disable "dist vendoring", otherwise cargo would try to access
   the network during the build phase.

Upstream changes:

Version 1.81.0 (2024-09-05)
==========================

Language
--------

- [Abort on uncaught panics in `extern "C"` functions.]
  (rust-lang/rust#116088)
- [Fix ambiguous cases of multiple `&` in elided self lifetimes.]
  (rust-lang/rust#117967)
- [Stabilize `#[expect]` for lints (RFC 2383),]
  (rust-lang/rust#120924) like `#[allow]`
  with a warning if the lint is _not_ fulfilled.
- [Change method resolution to constrain hidden types instead of
  rejecting method candidates.]
  (rust-lang/rust#123962)
- [Bump `elided_lifetimes_in_associated_constant` to deny.]
  (rust-lang/rust#124211)
- [`offset_from`: always allow pointers to point to the same
  address.] (rust-lang/rust#124921)
- [Allow constraining opaque types during subtyping in the trait
  system.] (rust-lang/rust#125447)
- [Allow constraining opaque types during various unsizing casts.]
  (rust-lang/rust#125610)
- [Deny keyword lifetimes pre-expansion.]
  (rust-lang/rust#126762)

Compiler
--------

- [Make casts of pointers to trait objects stricter.]
  (rust-lang/rust#120248)
- [Check alias args for well-formedness even if they have escaping
  bound vars.] (rust-lang/rust#123737)
- [Deprecate no-op codegen option `-Cinline-threshold=...`.]
  (rust-lang/rust#124712)
- [Re-implement a type-size based limit.]
  (rust-lang/rust#125507)
- [Properly account for alignment in `transmute` size checks.]
  (rust-lang/rust#125740)
- [Remove the `box_pointers` lint.]
  (rust-lang/rust#126018)
- [Ensure the interpreter checks bool/char for validity when they
  are used in a cast.] (rust-lang/rust#126265)
- [Improve coverage instrumentation for functions containing nested
  items.] (rust-lang/rust#127199)
- Target changes:
  - [Add Tier 3 `no_std` Xtensa targets:]
    (rust-lang/rust#125141) `xtensa-esp32-none-elf`,
    `xtensa-esp32s2-none-elf`, `xtensa-esp32s3-none-elf`
  - [Add Tier 3 `std` Xtensa targets:]
    (rust-lang/rust#126380) `xtensa-esp32-espidf`,
    `xtensa-esp32s2-espidf`, `xtensa-esp32s3-espidf`
  - [Add Tier 3 i686 Redox OS target:]
    (rust-lang/rust#126192) `i686-unknown-redox`
  - [Promote `arm64ec-pc-windows-msvc` to Tier 2.]
    (rust-lang/rust#126039)
  - [Promote `wasm32-wasip2` to Tier 2.]
    (rust-lang/rust#126967)
  - [Promote `loongarch64-unknown-linux-musl` to Tier 2 with host
    tools.] (rust-lang/rust#126298)
  - [Enable full tools and profiler for LoongArch Linux targets.]
    (rust-lang/rust#127078)
  - [Unconditionally warn on usage of `wasm32-wasi`.]
    (rust-lang/rust#126662) (see compatibility
    note below)
  - Refer to Rust's [platform support page][platform-support-doc]
    for more information on Rust's tiered platform support.

Libraries
---------

- [Split core's `PanicInfo` and std's `PanicInfo`.]
  (rust-lang/rust#115974) (see compatibility
  note below)
- [Generalize `{Rc,Arc}::make_mut()` to unsized types.]
  (rust-lang/rust#116113)
- [Replace sort implementations with stable `driftsort` and unstable
  `ipnsort`.] (rust-lang/rust#124032) All
  `slice::sort*` and `slice::select_nth*` methods are expected to
  see significant performance improvements. See the [research
  project] (https://github.com/Voultapher/sort-research-rs) for
  more details.
- [Document behavior of `create_dir_all` with respect to empty
  paths.] (rust-lang/rust#125112)
- [Fix interleaved output in the default panic hook when multiple
  threads panic simultaneously.]
  (rust-lang/rust#127397)
- Fix `Command`'s batch files argument escaping not working when
  file name has trailing whitespace or periods (CVE-2024-43402).

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

- [`core::error`] (https://doc.rust-lang.org/stable/core/error/index.html)
- [`hint::assert_unchecked`]
  (https://doc.rust-lang.org/stable/core/hint/fn.assert_unchecked.html)
- [`fs::exists`] (https://doc.rust-lang.org/stable/std/fs/fn.exists.html)
- [`AtomicBool::fetch_not`]
  (https://doc.rust-lang.org/stable/core/sync/atomic/struct.AtomicBool.html#method.fetch_not)
- [`Duration::abs_diff`]
  (https://doc.rust-lang.org/stable/core/time/struct.Duration.html#method.abs_diff)
- [`IoSlice::advance`]
  (https://doc.rust-lang.org/stable/std/io/struct.IoSlice.html#method.advance)
- [`IoSlice::advance_slices`]
  (https://doc.rust-lang.org/stable/std/io/struct.IoSlice.html#method.advance_slices)
- [`IoSliceMut::advance`]
  (https://doc.rust-lang.org/stable/std/io/struct.IoSliceMut.html#method.advance)
- [`IoSliceMut::advance_slices`]
  (https://doc.rust-lang.org/stable/std/io/struct.IoSliceMut.html#method.advance_slices)
- [`PanicHookInfo`]
  (https://doc.rust-lang.org/stable/std/panic/struct.PanicHookInfo.html)
- [`PanicInfo::message`]
  (https://doc.rust-lang.org/stable/core/panic/struct.PanicInfo.html#method.message)
- [`PanicMessage`]
  (https://doc.rust-lang.org/stable/core/panic/struct.PanicMessage.html)

These APIs are now stable in const contexts:

- [`char::from_u32_unchecked`]
  (https://doc.rust-lang.org/stable/core/char/fn.from_u32_unchecked.html)
  (function)
- [`char::from_u32_unchecked`]
  (https://doc.rust-lang.org/stable/core/primitive.char.html#method.from_u32_unchecked)
  (method)
- [`CStr::count_bytes`]
  (https://doc.rust-lang.org/stable/core/ffi/c_str/struct.CStr.html#method.count_bytes)
- [`CStr::from_ptr`]
  (https://doc.rust-lang.org/stable/core/ffi/c_str/struct.CStr.html#method.from_ptr)

Cargo
-----

- [Generated `.cargo_vcs_info.json` is always included, even when
  `--allow-dirty` is passed.]
  (rust-lang/cargo#13960)
- [Disallow `package.license-file` and `package.readme` pointing
  to non-existent files during packaging.]
  (rust-lang/cargo#13921)
- [Disallow passing `--release`/`--debug` flag along with the
  `--profile` flag.] (rust-lang/cargo#13971)
- [Remove `lib.plugin` key support in `Cargo.toml`. Rust plugin
  support has been deprecated for four years and was removed in
  1.75.0.] (rust-lang/cargo#13902)

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

* Usage of the `wasm32-wasi` target will now issue a compiler
  warning and request users switch to the `wasm32-wasip1` target
  instead. Both targets are the same, `wasm32-wasi` is only being
  renamed, and this [change to the WASI target]
  (https://blog.rust-lang.org/2024/04/09/updates-to-rusts-wasi-targets.html)
  is being done to enable removing `wasm32-wasi` in January 2025.

* We have renamed `std::panic::PanicInfo` to `std::panic::PanicHookInfo`.
  The old name will continue to work as an alias, but will result in
  a deprecation warning starting in Rust 1.82.0.

  `core::panic::PanicInfo` will remain unchanged, however, as this
  is now a *different type*.

  The reason is that these types have different roles:
  `std::panic::PanicHookInfo` is the argument to the [panic
  hook](https://doc.rust-lang.org/stable/std/panic/fn.set_hook.html)
  in std context (where panics can have an arbitrary payload),
  while `core::panic::PanicInfo` is the argument to the
  [`#[panic_handler]`](https://doc.rust-lang.org/nomicon/panic-handler.html)
  in no_std context (where panics always carry a formatted *message*).
  Separating these types allows us to add more useful methods to
  these types, such as `std::panic::PanicHookInfo::payload_as_str()`
  and `core::panic::PanicInfo::message()`.

* The new sort implementations may panic if a type's implementation
  of [`Ord`](https://doc.rust-lang.org/std/cmp/trait.Ord.html) (or
  the given comparison function) does not implement a [total
  order](https://en.wikipedia.org/wiki/Total_order) as the trait
  requires. `Ord`'s supertraits (`PartialOrd`, `Eq`, and `PartialEq`)
  must also be consistent. The previous implementations would not
  "notice" any problem, but the new implementations have a good chance
  of detecting inconsistencies, throwing a panic rather than returning
  knowingly unsorted data.
* [In very rare cases, a change in the internal evaluation order of the trait
  solver may result in new fatal overflow errors.]
  (rust-lang/rust#126128)

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 a Rust-for Linux `auto` CI job to check kernel builds.]
  (rust-lang/rust#125209)
netbsd-srcmastr pushed a commit to NetBSD/pkgsrc that referenced this pull request Nov 24, 2024
Pkgsrc changes:
 * Adapt patches, apply to new vendored crates where needed.
 * Back-port rust pull request 130110, "make dist vendoring configurable"
 * Disable "dist vendoring", otherwise cargo would try to access
   the network during the build phase.

Upstream changes:

Version 1.81.0 (2024-09-05)
==========================

Language
--------

- [Abort on uncaught panics in `extern "C"` functions.]
  (rust-lang/rust#116088)
- [Fix ambiguous cases of multiple `&` in elided self lifetimes.]
  (rust-lang/rust#117967)
- [Stabilize `#[expect]` for lints (RFC 2383),]
  (rust-lang/rust#120924) like `#[allow]`
  with a warning if the lint is _not_ fulfilled.
- [Change method resolution to constrain hidden types instead of
  rejecting method candidates.]
  (rust-lang/rust#123962)
- [Bump `elided_lifetimes_in_associated_constant` to deny.]
  (rust-lang/rust#124211)
- [`offset_from`: always allow pointers to point to the same
  address.] (rust-lang/rust#124921)
- [Allow constraining opaque types during subtyping in the trait
  system.] (rust-lang/rust#125447)
- [Allow constraining opaque types during various unsizing casts.]
  (rust-lang/rust#125610)
- [Deny keyword lifetimes pre-expansion.]
  (rust-lang/rust#126762)

Compiler
--------

- [Make casts of pointers to trait objects stricter.]
  (rust-lang/rust#120248)
- [Check alias args for well-formedness even if they have escaping
  bound vars.] (rust-lang/rust#123737)
- [Deprecate no-op codegen option `-Cinline-threshold=...`.]
  (rust-lang/rust#124712)
- [Re-implement a type-size based limit.]
  (rust-lang/rust#125507)
- [Properly account for alignment in `transmute` size checks.]
  (rust-lang/rust#125740)
- [Remove the `box_pointers` lint.]
  (rust-lang/rust#126018)
- [Ensure the interpreter checks bool/char for validity when they
  are used in a cast.] (rust-lang/rust#126265)
- [Improve coverage instrumentation for functions containing nested
  items.] (rust-lang/rust#127199)
- Target changes:
  - [Add Tier 3 `no_std` Xtensa targets:]
    (rust-lang/rust#125141) `xtensa-esp32-none-elf`,
    `xtensa-esp32s2-none-elf`, `xtensa-esp32s3-none-elf`
  - [Add Tier 3 `std` Xtensa targets:]
    (rust-lang/rust#126380) `xtensa-esp32-espidf`,
    `xtensa-esp32s2-espidf`, `xtensa-esp32s3-espidf`
  - [Add Tier 3 i686 Redox OS target:]
    (rust-lang/rust#126192) `i686-unknown-redox`
  - [Promote `arm64ec-pc-windows-msvc` to Tier 2.]
    (rust-lang/rust#126039)
  - [Promote `wasm32-wasip2` to Tier 2.]
    (rust-lang/rust#126967)
  - [Promote `loongarch64-unknown-linux-musl` to Tier 2 with host
    tools.] (rust-lang/rust#126298)
  - [Enable full tools and profiler for LoongArch Linux targets.]
    (rust-lang/rust#127078)
  - [Unconditionally warn on usage of `wasm32-wasi`.]
    (rust-lang/rust#126662) (see compatibility
    note below)
  - Refer to Rust's [platform support page][platform-support-doc]
    for more information on Rust's tiered platform support.

Libraries
---------

- [Split core's `PanicInfo` and std's `PanicInfo`.]
  (rust-lang/rust#115974) (see compatibility
  note below)
- [Generalize `{Rc,Arc}::make_mut()` to unsized types.]
  (rust-lang/rust#116113)
- [Replace sort implementations with stable `driftsort` and unstable
  `ipnsort`.] (rust-lang/rust#124032) All
  `slice::sort*` and `slice::select_nth*` methods are expected to
  see significant performance improvements. See the [research
  project] (https://github.com/Voultapher/sort-research-rs) for
  more details.
- [Document behavior of `create_dir_all` with respect to empty
  paths.] (rust-lang/rust#125112)
- [Fix interleaved output in the default panic hook when multiple
  threads panic simultaneously.]
  (rust-lang/rust#127397)
- Fix `Command`'s batch files argument escaping not working when
  file name has trailing whitespace or periods (CVE-2024-43402).

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

- [`core::error`] (https://doc.rust-lang.org/stable/core/error/index.html)
- [`hint::assert_unchecked`]
  (https://doc.rust-lang.org/stable/core/hint/fn.assert_unchecked.html)
- [`fs::exists`] (https://doc.rust-lang.org/stable/std/fs/fn.exists.html)
- [`AtomicBool::fetch_not`]
  (https://doc.rust-lang.org/stable/core/sync/atomic/struct.AtomicBool.html#method.fetch_not)
- [`Duration::abs_diff`]
  (https://doc.rust-lang.org/stable/core/time/struct.Duration.html#method.abs_diff)
- [`IoSlice::advance`]
  (https://doc.rust-lang.org/stable/std/io/struct.IoSlice.html#method.advance)
- [`IoSlice::advance_slices`]
  (https://doc.rust-lang.org/stable/std/io/struct.IoSlice.html#method.advance_slices)
- [`IoSliceMut::advance`]
  (https://doc.rust-lang.org/stable/std/io/struct.IoSliceMut.html#method.advance)
- [`IoSliceMut::advance_slices`]
  (https://doc.rust-lang.org/stable/std/io/struct.IoSliceMut.html#method.advance_slices)
- [`PanicHookInfo`]
  (https://doc.rust-lang.org/stable/std/panic/struct.PanicHookInfo.html)
- [`PanicInfo::message`]
  (https://doc.rust-lang.org/stable/core/panic/struct.PanicInfo.html#method.message)
- [`PanicMessage`]
  (https://doc.rust-lang.org/stable/core/panic/struct.PanicMessage.html)

These APIs are now stable in const contexts:

- [`char::from_u32_unchecked`]
  (https://doc.rust-lang.org/stable/core/char/fn.from_u32_unchecked.html)
  (function)
- [`char::from_u32_unchecked`]
  (https://doc.rust-lang.org/stable/core/primitive.char.html#method.from_u32_unchecked)
  (method)
- [`CStr::count_bytes`]
  (https://doc.rust-lang.org/stable/core/ffi/c_str/struct.CStr.html#method.count_bytes)
- [`CStr::from_ptr`]
  (https://doc.rust-lang.org/stable/core/ffi/c_str/struct.CStr.html#method.from_ptr)

Cargo
-----

- [Generated `.cargo_vcs_info.json` is always included, even when
  `--allow-dirty` is passed.]
  (rust-lang/cargo#13960)
- [Disallow `package.license-file` and `package.readme` pointing
  to non-existent files during packaging.]
  (rust-lang/cargo#13921)
- [Disallow passing `--release`/`--debug` flag along with the
  `--profile` flag.] (rust-lang/cargo#13971)
- [Remove `lib.plugin` key support in `Cargo.toml`. Rust plugin
  support has been deprecated for four years and was removed in
  1.75.0.] (rust-lang/cargo#13902)

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

* Usage of the `wasm32-wasi` target will now issue a compiler
  warning and request users switch to the `wasm32-wasip1` target
  instead. Both targets are the same, `wasm32-wasi` is only being
  renamed, and this [change to the WASI target]
  (https://blog.rust-lang.org/2024/04/09/updates-to-rusts-wasi-targets.html)
  is being done to enable removing `wasm32-wasi` in January 2025.

* We have renamed `std::panic::PanicInfo` to `std::panic::PanicHookInfo`.
  The old name will continue to work as an alias, but will result in
  a deprecation warning starting in Rust 1.82.0.

  `core::panic::PanicInfo` will remain unchanged, however, as this
  is now a *different type*.

  The reason is that these types have different roles:
  `std::panic::PanicHookInfo` is the argument to the [panic
  hook](https://doc.rust-lang.org/stable/std/panic/fn.set_hook.html)
  in std context (where panics can have an arbitrary payload),
  while `core::panic::PanicInfo` is the argument to the
  [`#[panic_handler]`](https://doc.rust-lang.org/nomicon/panic-handler.html)
  in no_std context (where panics always carry a formatted *message*).
  Separating these types allows us to add more useful methods to
  these types, such as `std::panic::PanicHookInfo::payload_as_str()`
  and `core::panic::PanicInfo::message()`.

* The new sort implementations may panic if a type's implementation
  of [`Ord`](https://doc.rust-lang.org/std/cmp/trait.Ord.html) (or
  the given comparison function) does not implement a [total
  order](https://en.wikipedia.org/wiki/Total_order) as the trait
  requires. `Ord`'s supertraits (`PartialOrd`, `Eq`, and `PartialEq`)
  must also be consistent. The previous implementations would not
  "notice" any problem, but the new implementations have a good chance
  of detecting inconsistencies, throwing a panic rather than returning
  knowingly unsorted data.
* [In very rare cases, a change in the internal evaluation order of the trait
  solver may result in new fatal overflow errors.]
  (rust-lang/rust#126128)

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 a Rust-for Linux `auto` CI job to check kernel builds.]
  (rust-lang/rust#125209)
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
Labels
A-code-coverage Area: Source-based code coverage (-Cinstrument-coverage) merged-by-bors This PR was explicitly merged by bors. relnotes Marks issues that should be documented in the release notes of the next release. S-waiting-on-bors Status: Waiting on bors to run and complete tests. Bors will change the label on completion. T-compiler Relevant to the compiler team, which will review and decide on the PR/issue.
Projects
None yet
Development

Successfully merging this pull request may close these issues.

Coverage spans should not overlap nested items
6 participants