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Stabilize some MaybeUninit
behavior as const
#90896
Conversation
Seems like we never added a test for these. Please make sure they are tested in a const context with some reasonablish use case (can we perform examples from the docs in const contexts now?) |
My personal use case for field-by-field initialization of a struct. This would have to be done in a single method for a test, as mut refs aren't yet const stable. |
tests can use unstable features, it seems ok to me to use const mut refs for such a test |
I knew that; I wasn't sure because you alluded to having a doctest. I'll add a regular UI test momentarily. |
Ah sorry. I meant whether the doc examples contain something that we could copy into a test and make const. But your example is a great test, too, so let's roll with that |
r? rust-lang/libs-api cc @rust-lang/wg-const-eval |
Ah gotcha. Either way works 🤷🏽 |
@@ -115,7 +114,7 @@ | |||
#![feature(const_intrinsic_copy)] | |||
#![feature(const_intrinsic_forget)] | |||
#![feature(const_likely)] | |||
#![feature(const_maybe_uninit_as_ptr)] | |||
#![feature(const_maybe_uninit_as_mut_ptr)] | |||
#![feature(const_maybe_uninit_assume_init)] |
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Can this be removed now?
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No, as the method takes a mutable parameter. const_mut_refs
hasn't yet been stabilized.
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This is for assume_init
, which is being stabilized... is it not? I am confused.
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Whoops, when I responded I thought misread where the code was. I'll check the necessity of this.
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Removing this results in the following errors:
error: `maybe_uninit::MaybeUninit::<T>::as_mut_ptr` is not yet stable as a const fn
--> library/core/src/mem/maybe_uninit.rs:915:19
|
915 | &mut *self.as_mut_ptr()
| ^^^^^^^^^^^^^^^^^
|
= help: add `#![feature(const_maybe_uninit_as_mut_ptr)]` to the crate attributes to enable
error: `maybe_uninit::MaybeUninit::<T>::as_mut_ptr` is not yet stable as a const fn
--> library/core/src/ptr/mod.rs:374:32
|
374 | copy_nonoverlapping(x, tmp.as_mut_ptr(), 1);
| ^^^^^^^^^^^^^^^^
|
= help: add `#![feature(const_maybe_uninit_as_mut_ptr)]` to the crate attributes to enable
error: `maybe_uninit::MaybeUninit::<T>::as_mut_ptr` is not yet stable as a const fn
--> library/core/src/ptr/mod.rs:485:17
|
485 | let t = t.as_mut_ptr() as *mut u8;
| ^^^^^^^^^^^^^^
|
= help: add `#![feature(const_maybe_uninit_as_mut_ptr)]` to the crate attributes to enable
error: `maybe_uninit::MaybeUninit::<T>::as_mut_ptr` is not yet stable as a const fn
--> library/core/src/ptr/mod.rs:511:17
|
511 | let t = t.as_mut_ptr() as *mut u8;
| ^^^^^^^^^^^^^^
|
= help: add `#![feature(const_maybe_uninit_as_mut_ptr)]` to the crate attributes to enable
error: `maybe_uninit::MaybeUninit::<T>::as_mut_ptr` is not yet stable as a const fn
--> library/core/src/ptr/mod.rs:701:34
|
701 | copy_nonoverlapping(src, tmp.as_mut_ptr(), 1);
| ^^^^^^^^^^^^^^^^
|
= help: add `#![feature(const_maybe_uninit_as_mut_ptr)]` to the crate attributes to enable
error: `maybe_uninit::MaybeUninit::<T>::as_mut_ptr` is not yet stable as a const fn
--> library/core/src/ptr/mod.rs:793:47
|
793 | copy_nonoverlapping(src as *const u8, tmp.as_mut_ptr() as *mut u8, mem::size_of::<T>());
| ^^^^^^^^^^^^^^^^
|
= help: add `#![feature(const_maybe_uninit_as_mut_ptr)]` to the crate attributes to enable
error: could not compile `core` due to 6 previous errors
As such I'll be leaving the attribute in.
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I was asking about the const_maybe_uninit_assume_init
, not the const_maybe_uninit_as_mut_ptr
. (Note the line this comment is attached to.)
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Yeah, that probably should have been explicitly stated 🙂 I'll check when I'm on my laptop and send a follow-up if necessary.
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Thanks. :)
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Removing that line results in an error on line 496 of the same file (inside MaybeUninit::write
). That's for the assume_init_mut
method.
So...I think this means that const stability isn't currently subject to the same checks, in that a feature can be both simultaneously stable and unstable? If that's the case we should fix that.
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Ah I see, makes sense. I opened an issue for this: #91357
@rfcbot merge |
@rust-lang/libs-api This stabilizes impl<T> MaybeUninit<T> {
pub const fn as_ptr(&self) -> *const T;
pub const unsafe fn assume_init(self) -> T;
pub const unsafe fn assume_init_ref(&self) -> &T;
} |
What about |
You can't have &mut in a const fn signature on stable. error[E0658]: mutable references are not allowed in constant functions
--> src/lib.rs:1:12
|
1 | const fn f(_: &mut u8) {}
| ^
|
= note: see issue #57349 <https://github.com/rust-lang/rust/issues/57349> for more information |
Team member @dtolnay has proposed to merge this. The next step is review by the rest of the tagged team members: No concerns currently listed. Once a majority of reviewers approve (and at most 2 approvals are outstanding), this will enter its final comment period. If you spot a major issue that hasn't been raised at any point in this process, please speak up! See this document for info about what commands tagged team members can give me. |
🔔 This is now entering its final comment period, as per the review above. 🔔 |
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Bumped stabilization to 1.59 and moved to a unit test. The other review comment I marked resolved as the feature gate is necessary (see my response for the error). @rustbot label: -S-waiting-on-author +S-waiting-on-review |
@bors r+ rollup |
📌 Commit 44b5b83 has been approved by |
…askrgr Rollup of 3 pull requests Successful merges: - rust-lang#90896 (Stabilize some `MaybeUninit` behavior as const) - rust-lang#91254 (Only check for errors in predicate when skipping impl assembly) - rust-lang#91303 (Miri: fix alignment check in array initialization) Failed merges: r? `@ghost` `@rustbot` modify labels: rollup
CTFE: support assert_zero_valid and assert_uninit_valid This ensures the implementation of all three type-based assert_ intrinsics remains consistent in Miri. `assert_inhabited` recently got stabilized in rust-lang#90896 (meaning stable `const fn` can call it), so do the same with these other intrinsics. Cc `@rust-lang/wg-const-eval`
CTFE: support assert_zero_valid and assert_uninit_valid This ensures the implementation of all three type-based assert_ intrinsics remains consistent in Miri. `assert_inhabited` recently got stabilized in rust-lang#90896 (meaning stable `const fn` can call it), so do the same with these other intrinsics. Cc ``@rust-lang/wg-const-eval``
CTFE: support assert_zero_valid and assert_uninit_valid This ensures the implementation of all three type-based assert_ intrinsics remains consistent in Miri. `assert_inhabited` recently got stabilized in rust-lang#90896 (meaning stable `const fn` can call it), so do the same with these other intrinsics. Cc ```@rust-lang/wg-const-eval```
`const_maybe_uninit_as_ptr` has been stabilized by <rust-lang/rust#90896>.
Update RELEASES for 1.58. From what I can tell: * `NonZero{unsigned}::is_power_of_two` was stabilized in 1.59: rust-lang#91301 * `MaybeUninit` const was added in 1.59: rust-lang#90896
Update RELEASES for 1.58. From what I can tell: * `NonZero{unsigned}::is_power_of_two` was stabilized in 1.59: rust-lang#91301 * `MaybeUninit` const was added in 1.59: rust-lang#90896
Pkgsrc changes: * Bump available bootstraps to 1.57.0. * For some reason, the vendor/libc checksums don't need fixing. * Bump required external LLVM to 12.0, according to upstream change log. * Adapt the Darwin linker patch. (For some reason I've not figured out yet, cargo is a lot more verbose while building, echoes the rustc invocation.) Upstream changes: Version 1.58.1 (2022-01-19) =========================== * Fix race condition in `std::fs::remove_dir_all` ([CVE-2022-21658]) * [Handle captured arguments in the `useless_format` Clippy lint][clippy/8295] * [Move `non_send_fields_in_send_ty` Clippy lint to nursery][clippy/8075] * [Fix wrong error message displayed when some imports are missing][91254] * [Fix rustfmt not formatting generated files from stdin][92912] [CVE-2022-21658]: https://www.cve.org/CVERecord?id=CVE-2022-21658] [91254]: rust-lang/rust#91254 [92912]: rust-lang/rust#92912 [clippy/8075]: rust-lang/rust-clippy#8075 [clippy/8295]: rust-lang/rust-clippy#8295 Version 1.58.0 (2022-01-13) ========================== Language -------- - [Format strings can now capture arguments simply by writing `{ident}` in the string.][90473] This works in all macros accepting format strings. Support for this in `panic!` (`panic!("{ident}")`) requires the 2021 edition; panic invocations in previous editions that appear to be trying to use this will result in a warning lint about not having the intended effect. - [`*const T` pointers can now be dereferenced in const contexts.][89551] - [The rules for when a generic struct implements `Unsize` have been relaxed.][90417] Compiler -------- - [Add LLVM CFI support to the Rust compiler][89652] - [Stabilize -Z strip as -C strip][90058]. Note that while release builds already don't add debug symbols for the code you compile, the compiled standard library that ships with Rust includes debug symbols, so you may want to use the `strip` option to remove these symbols to produce smaller release binaries. Note that this release only includes support in rustc, not directly in cargo. - [Add support for LLVM coverage mapping format versions 5 and 6][91207] - [Emit LLVM optimization remarks when enabled with `-Cremark`][90833] - [Update the minimum external LLVM to 12][90175] - [Add `x86_64-unknown-none` at Tier 3*][89062] - [Build musl dist artifacts with debuginfo enabled][90733]. When building release binaries using musl, you may want to use the newly stabilized strip option to remove these debug symbols, reducing the size of your binaries. - [Don't abort compilation after giving a lint error][87337] - [Error messages point at the source of trait bound obligations in more places][89580] \* Refer to Rust's [platform support page][platform-support-doc] for more information on Rust's tiered platform support. Libraries --------- - [All remaining functions in the standard library have `#[must_use]` annotations where appropriate][89692], producing a warning when ignoring their return value. This helps catch mistakes such as expecting a function to mutate a value in place rather than return a new value. - [Paths are automatically canonicalized on Windows for operations that support it][89174] - [Re-enable debug checks for `copy` and `copy_nonoverlapping`][90041] - [Implement `RefUnwindSafe` for `Rc<T>`][87467] - [Make RSplit<T, P>: Clone not require T: Clone][90117] - [Implement `Termination` for `Result<Infallible, E>`][88601]. This allows writing `fn main() -> Result<Infallible, ErrorType>`, for a program whose successful exits never involve returning from `main` (for instance, a program that calls `exit`, or that uses `exec` to run another program). Stabilized APIs --------------- - [`Metadata::is_symlink`] - [`Path::is_symlink`] - [`{integer}::saturating_div`] - [`Option::unwrap_unchecked`] - [`Result::unwrap_unchecked`] - [`Result::unwrap_err_unchecked`] - [`NonZero{unsigned}::is_power_of_two`] - [`File::options`] These APIs are now usable in const contexts: - [`Duration::new`] - [`Duration::checked_add`] - [`Duration::saturating_add`] - [`Duration::checked_sub`] - [`Duration::saturating_sub`] - [`Duration::checked_mul`] - [`Duration::saturating_mul`] - [`Duration::checked_div`] - [`MaybeUninit::as_ptr`] - [`MaybeUninit::as_mut_ptr`] - [`MaybeUninit::assume_init`] - [`MaybeUninit::assume_init_ref`] Cargo ----- - [Add --message-format for install command][cargo/10107] - [Warn when alias shadows external subcommand][cargo/10082] Rustdoc ------- - [Show all Deref implementations recursively in rustdoc][90183] - [Use computed visibility in rustdoc][88447] Compatibility Notes ------------------- - [Try all stable method candidates first before trying unstable ones][90329]. This change ensures that adding new nightly-only methods to the Rust standard library will not break code invoking methods of the same name from traits outside the standard library. - Windows: [`std::process::Command` will no longer search the current directory for executables.][87704] - [All proc-macro backward-compatibility lints are now deny-by-default.][88041] - [proc_macro: Append .0 to unsuffixed float if it would otherwise become int token][90297] - [Refactor weak symbols in std::sys::unix][90846]. This optimizes accesses to glibc functions, by avoiding the use of dlopen. This does not increase the [minimum expected version of glibc](https://doc.rust-lang.org/nightly/rustc/platform-support.html). However, software distributions that use symbol versions to detect library dependencies, and which take weak symbols into account in that analysis, may detect rust binaries as requiring newer versions of glibc. - [rustdoc now rejects some unexpected semicolons in doctests][91026] Internal Changes ---------------- These changes provide no direct user facing benefits, but represent significant improvements to the internals and overall performance of rustc and related tools. - [Implement coherence checks for negative trait impls][90104] - [Add rustc lint, warning when iterating over hashmaps][89558] - [Optimize live point computation][90491] - [Enable verification for 1/32nd of queries loaded from disk][90361] - [Implement version of normalize_erasing_regions that allows for normalization failure][91255] [87337]: rust-lang/rust#87337 [87467]: rust-lang/rust#87467 [87704]: rust-lang/rust#87704 [88041]: rust-lang/rust#88041 [88300]: rust-lang/rust#88300 [88447]: rust-lang/rust#88447 [88601]: rust-lang/rust#88601 [88624]: rust-lang/rust#88624 [89062]: rust-lang/rust#89062 [89174]: rust-lang/rust#89174 [89542]: rust-lang/rust#89542 [89551]: rust-lang/rust#89551 [89558]: rust-lang/rust#89558 [89580]: rust-lang/rust#89580 [89652]: rust-lang/rust#89652 [89677]: rust-lang/rust#89677 [89951]: rust-lang/rust#89951 [90041]: rust-lang/rust#90041 [90058]: rust-lang/rust#90058 [90104]: rust-lang/rust#90104 [90117]: rust-lang/rust#90117 [90175]: rust-lang/rust#90175 [90183]: rust-lang/rust#90183 [90297]: rust-lang/rust#90297 [90329]: rust-lang/rust#90329 [90361]: rust-lang/rust#90361 [90417]: rust-lang/rust#90417 [90473]: rust-lang/rust#90473 [90491]: rust-lang/rust#90491 [90733]: rust-lang/rust#90733 [90833]: rust-lang/rust#90833 [90846]: rust-lang/rust#90846 [90896]: rust-lang/rust#90896 [91026]: rust-lang/rust#91026 [91207]: rust-lang/rust#91207 [91255]: rust-lang/rust#91255 [91301]: rust-lang/rust#91301 [cargo/10082]: rust-lang/cargo#10082 [cargo/10107]: rust-lang/cargo#10107 [`Metadata::is_symlink`]: https://doc.rust-lang.org/stable/std/fs/struct.Metadata.html#method.is_symlink [`Path::is_symlink`]: https://doc.rust-lang.org/stable/std/path/struct.Path.html#method.is_symlink [`{integer}::saturating_div`]: https://doc.rust-lang.org/stable/std/primitive.i8.html#method.saturating_div [`Option::unwrap_unchecked`]: https://doc.rust-lang.org/stable/std/option/enum.Option.html#method.unwrap_unchecked [`Result::unwrap_unchecked`]: https://doc.rust-lang.org/stable/std/result/enum.Result.html#method.unwrap_unchecked [`Result::unwrap_err_unchecked`]: https://doc.rust-lang.org/stable/std/result/enum.Result.html#method.unwrap_err_unchecked [`NonZero{unsigned}::is_power_of_two`]: https://doc.rust-lang.org/stable/std/num/struct.NonZeroU8.html#method.is_power_of_two [`File::options`]: https://doc.rust-lang.org/stable/std/fs/struct.File.html#method.options [`unix::process::ExitStatusExt::core_dumped`]: https://doc.rust-lang.org/stable/std/os/unix/process/trait.ExitStatusExt.html#tymethod.core_dumped [`unix::process::ExitStatusExt::stopped_signal`]: https://doc.rust-lang.org/stable/std/os/unix/process/trait.ExitStatusExt.html#tymethod.stopped_signal [`unix::process::ExitStatusExt::continued`]: https://doc.rust-lang.org/stable/std/os/unix/process/trait.ExitStatusExt.html#tymethod.continued [`unix::process::ExitStatusExt::into_raw`]: https://doc.rust-lang.org/stable/std/os/unix/process/trait.ExitStatusExt.html#tymethod.into_raw [`Duration::new`]: https://doc.rust-lang.org/stable/std/time/struct.Duration.html#method.new [`Duration::checked_add`]: https://doc.rust-lang.org/stable/std/time/struct.Duration.html#method.checked_add [`Duration::saturating_add`]: https://doc.rust-lang.org/stable/std/time/struct.Duration.html#method.saturating_add [`Duration::checked_sub`]: https://doc.rust-lang.org/stable/std/time/struct.Duration.html#method.checked_sub [`Duration::saturating_sub`]: https://doc.rust-lang.org/stable/std/time/struct.Duration.html#method.saturating_sub [`Duration::checked_mul`]: https://doc.rust-lang.org/stable/std/time/struct.Duration.html#method.checked_mul [`Duration::saturating_mul`]: https://doc.rust-lang.org/stable/std/time/struct.Duration.html#method.saturating_mul [`Duration::checked_div`]: https://doc.rust-lang.org/stable/std/time/struct.Duration.html#method.checked_div [`Duration::as_secs_f64`]: https://doc.rust-lang.org/stable/std/time/struct.Duration.html#method.as_secs_f64 [`Duration::as_secs_f32`]: https://doc.rust-lang.org/stable/std/time/struct.Duration.html#method.as_secs_f32 [`Duration::from_secs_f64`]: https://doc.rust-lang.org/stable/std/time/struct.Duration.html#method.from_secs_f64 [`Duration::from_secs_f32`]: https://doc.rust-lang.org/stable/std/time/struct.Duration.html#method.from_secs_f32 [`Duration::mul_f64`]: https://doc.rust-lang.org/stable/std/time/struct.Duration.html#method.mul_f64 [`Duration::mul_f32`]: https://doc.rust-lang.org/stable/std/time/struct.Duration.html#method.mul_f32 [`Duration::div_f64`]: https://doc.rust-lang.org/stable/std/time/struct.Duration.html#method.div_f64 [`Duration::div_f32`]: https://doc.rust-lang.org/stable/std/time/struct.Duration.html#method.div_f32 [`Duration::div_duration_f64`]: https://doc.rust-lang.org/stable/std/time/struct.Duration.html#method.div_duration_f64 [`Duration::div_duration_f32`]: https://doc.rust-lang.org/stable/std/time/struct.Duration.html#method.div_duration_f32 [`MaybeUninit::as_ptr`]: https://doc.rust-lang.org/stable/std/mem/union.MaybeUninit.html#method.as_ptr [`MaybeUninit::as_mut_ptr`]: https://doc.rust-lang.org/stable/std/mem/union.MaybeUninit.html#method.as_mut_ptr [`MaybeUninit::assume_init`]: https://doc.rust-lang.org/stable/std/mem/union.MaybeUninit.html#method.assume_init [`MaybeUninit::assume_init_ref`]: https://doc.rust-lang.org/stable/std/mem/union.MaybeUninit.html#method.assume_init_ref
Pkgsrc changes: * Bump bootstrap kit version to 1.57.0. * Bump require external LLVM to 12.0, according to upstream change log. * Adjust patches as needed, adjust line numbers. * Update checksum adjustments. For some reason the vendor/libc checksum doesn't need fixing, apparently, it remains as commented out. * Add makefile to do all the NetBSD boostrap/cross builds (do-cross.mk). Allow passing in additions to CONFIGURE_ARGS via ADD_CONFIGURE_ARGS. Upstream changes: Version 1.58.1 (2022-01-19) =========================== * Fix race condition in `std::fs::remove_dir_all` ([CVE-2022-21658]) * [Handle captured arguments in the `useless_format` Clippy lint][clippy/8295] * [Move `non_send_fields_in_send_ty` Clippy lint to nursery][clippy/8075] * [Fix wrong error message displayed when some imports are missing][91254] * [Fix rustfmt not formatting generated files from stdin][92912] [CVE-2022-21658]: https://www.cve.org/CVERecord?id=CVE-2022-21658] [91254]: rust-lang/rust#91254 [92912]: rust-lang/rust#92912 [clippy/8075]: rust-lang/rust-clippy#8075 [clippy/8295]: rust-lang/rust-clippy#8295 Version 1.58.0 (2022-01-13) ========================== Language -------- - [Format strings can now capture arguments simply by writing `{ident}` in the string.][90473] This works in all macros accepting format strings. Support for this in `panic!` (`panic!("{ident}")`) requires the 2021 edition; panic invocations in previous editions that appear to be trying to use this will result in a warning lint about not having the intended effect. - [`*const T` pointers can now be dereferenced in const contexts.][89551] - [The rules for when a generic struct implements `Unsize` have been relaxed.][90417] Compiler -------- - [Add LLVM CFI support to the Rust compiler][89652] - [Stabilize -Z strip as -C strip][90058]. Note that while release builds already don't add debug symbols for the code you compile, the compiled standard library that ships with Rust includes debug symbols, so you may want to use the `strip` option to remove these symbols to produce smaller release binaries. Note that this release only includes support in rustc, not directly in cargo. - [Add support for LLVM coverage mapping format versions 5 and 6][91207] - [Emit LLVM optimization remarks when enabled with `-Cremark`][90833] - [Update the minimum external LLVM to 12][90175] - [Add `x86_64-unknown-none` at Tier 3*][89062] - [Build musl dist artifacts with debuginfo enabled][90733]. When building release binaries using musl, you may want to use the newly stabilized strip option to remove these debug symbols, reducing the size of your binaries. - [Don't abort compilation after giving a lint error][87337] - [Error messages point at the source of trait bound obligations in more places][89580] \* Refer to Rust's [platform support page][platform-support-doc] for more information on Rust's tiered platform support. Libraries --------- - [All remaining functions in the standard library have `#[must_use]` annotations where appropriate][89692], producing a warning when ignoring their return value. This helps catch mistakes such as expecting a function to mutate a value in place rather than return a new value. - [Paths are automatically canonicalized on Windows for operations that support it][89174] - [Re-enable debug checks for `copy` and `copy_nonoverlapping`][90041] - [Implement `RefUnwindSafe` for `Rc<T>`][87467] - [Make RSplit<T, P>: Clone not require T: Clone][90117] - [Implement `Termination` for `Result<Infallible, E>`][88601]. This allows writing `fn main() -> Result<Infallible, ErrorType>`, for a program whose successful exits never involve returning from `main` (for instance, a program that calls `exit`, or that uses `exec` to run another program). Stabilized APIs --------------- - [`Metadata::is_symlink`] - [`Path::is_symlink`] - [`{integer}::saturating_div`] - [`Option::unwrap_unchecked`] - [`Result::unwrap_unchecked`] - [`Result::unwrap_err_unchecked`] - [`NonZero{unsigned}::is_power_of_two`] - [`File::options`] These APIs are now usable in const contexts: - [`Duration::new`] - [`Duration::checked_add`] - [`Duration::saturating_add`] - [`Duration::checked_sub`] - [`Duration::saturating_sub`] - [`Duration::checked_mul`] - [`Duration::saturating_mul`] - [`Duration::checked_div`] - [`MaybeUninit::as_ptr`] - [`MaybeUninit::as_mut_ptr`] - [`MaybeUninit::assume_init`] - [`MaybeUninit::assume_init_ref`] Cargo ----- - [Add --message-format for install command][cargo/10107] - [Warn when alias shadows external subcommand][cargo/10082] Rustdoc ------- - [Show all Deref implementations recursively in rustdoc][90183] - [Use computed visibility in rustdoc][88447] Compatibility Notes ------------------- - [Try all stable method candidates first before trying unstable ones][90329]. This change ensures that adding new nightly-only methods to the Rust standard library will not break code invoking methods of the same name from traits outside the standard library. - Windows: [`std::process::Command` will no longer search the current directory for executables.][87704] - [All proc-macro backward-compatibility lints are now deny-by-default.][88041] - [proc_macro: Append .0 to unsuffixed float if it would otherwise become int token][90297] - [Refactor weak symbols in std::sys::unix][90846]. This optimizes accesses to glibc functions, by avoiding the use of dlopen. This does not increase the [minimum expected version of glibc](https://doc.rust-lang.org/nightly/rustc/platform-support.html). However, software distributions that use symbol versions to detect library dependencies, and which take weak symbols into account in that analysis, may detect rust binaries as requiring newer versions of glibc. - [rustdoc now rejects some unexpected semicolons in doctests][91026] Internal Changes ---------------- These changes provide no direct user facing benefits, but represent significant improvements to the internals and overall performance of rustc and related tools. - [Implement coherence checks for negative trait impls][90104] - [Add rustc lint, warning when iterating over hashmaps][89558] - [Optimize live point computation][90491] - [Enable verification for 1/32nd of queries loaded from disk][90361] - [Implement version of normalize_erasing_regions that allows for normalization failure][91255] [87337]: rust-lang/rust#87337 [87467]: rust-lang/rust#87467 [87704]: rust-lang/rust#87704 [88041]: rust-lang/rust#88041 [88300]: rust-lang/rust#88300 [88447]: rust-lang/rust#88447 [88601]: rust-lang/rust#88601 [88624]: rust-lang/rust#88624 [89062]: rust-lang/rust#89062 [89174]: rust-lang/rust#89174 [89542]: rust-lang/rust#89542 [89551]: rust-lang/rust#89551 [89558]: rust-lang/rust#89558 [89580]: rust-lang/rust#89580 [89652]: rust-lang/rust#89652 [89677]: rust-lang/rust#89677 [89951]: rust-lang/rust#89951 [90041]: rust-lang/rust#90041 [90058]: rust-lang/rust#90058 [90104]: rust-lang/rust#90104 [90117]: rust-lang/rust#90117 [90175]: rust-lang/rust#90175 [90183]: rust-lang/rust#90183 [90297]: rust-lang/rust#90297 [90329]: rust-lang/rust#90329 [90361]: rust-lang/rust#90361 [90417]: rust-lang/rust#90417 [90473]: rust-lang/rust#90473 [90491]: rust-lang/rust#90491 [90733]: rust-lang/rust#90733 [90833]: rust-lang/rust#90833 [90846]: rust-lang/rust#90846 [90896]: rust-lang/rust#90896 [91026]: rust-lang/rust#91026 [91207]: rust-lang/rust#91207 [91255]: rust-lang/rust#91255 [91301]: rust-lang/rust#91301 [cargo/10082]: rust-lang/cargo#10082 [cargo/10107]: rust-lang/cargo#10107 [`Metadata::is_symlink`]: https://doc.rust-lang.org/stable/std/fs/struct.Metadata.html#method.is_symlink [`Path::is_symlink`]: https://doc.rust-lang.org/stable/std/path/struct.Path.html#method.is_symlink [`{integer}::saturating_div`]: https://doc.rust-lang.org/stable/std/primitive.i8.html#method.saturating_div [`Option::unwrap_unchecked`]: https://doc.rust-lang.org/stable/std/option/enum.Option.html#method.unwrap_unchecked [`Result::unwrap_unchecked`]: https://doc.rust-lang.org/stable/std/result/enum.Result.html#method.unwrap_unchecked [`Result::unwrap_err_unchecked`]: https://doc.rust-lang.org/stable/std/result/enum.Result.html#method.unwrap_err_unchecked [`NonZero{unsigned}::is_power_of_two`]: https://doc.rust-lang.org/stable/std/num/struct.NonZeroU8.html#method.is_power_of_two [`File::options`]: https://doc.rust-lang.org/stable/std/fs/struct.File.html#method.options [`unix::process::ExitStatusExt::core_dumped`]: https://doc.rust-lang.org/stable/std/os/unix/process/trait.ExitStatusExt.html#tymethod.core_dumped [`unix::process::ExitStatusExt::stopped_signal`]: https://doc.rust-lang.org/stable/std/os/unix/process/trait.ExitStatusExt.html#tymethod.stopped_signal [`unix::process::ExitStatusExt::continued`]: https://doc.rust-lang.org/stable/std/os/unix/process/trait.ExitStatusExt.html#tymethod.continued [`unix::process::ExitStatusExt::into_raw`]: https://doc.rust-lang.org/stable/std/os/unix/process/trait.ExitStatusExt.html#tymethod.into_raw [`Duration::new`]: https://doc.rust-lang.org/stable/std/time/struct.Duration.html#method.new [`Duration::checked_add`]: https://doc.rust-lang.org/stable/std/time/struct.Duration.html#method.checked_add [`Duration::saturating_add`]: https://doc.rust-lang.org/stable/std/time/struct.Duration.html#method.saturating_add [`Duration::checked_sub`]: https://doc.rust-lang.org/stable/std/time/struct.Duration.html#method.checked_sub [`Duration::saturating_sub`]: https://doc.rust-lang.org/stable/std/time/struct.Duration.html#method.saturating_sub [`Duration::checked_mul`]: https://doc.rust-lang.org/stable/std/time/struct.Duration.html#method.checked_mul [`Duration::saturating_mul`]: https://doc.rust-lang.org/stable/std/time/struct.Duration.html#method.saturating_mul [`Duration::checked_div`]: https://doc.rust-lang.org/stable/std/time/struct.Duration.html#method.checked_div [`Duration::as_secs_f64`]: https://doc.rust-lang.org/stable/std/time/struct.Duration.html#method.as_secs_f64 [`Duration::as_secs_f32`]: https://doc.rust-lang.org/stable/std/time/struct.Duration.html#method.as_secs_f32 [`Duration::from_secs_f64`]: https://doc.rust-lang.org/stable/std/time/struct.Duration.html#method.from_secs_f64 [`Duration::from_secs_f32`]: https://doc.rust-lang.org/stable/std/time/struct.Duration.html#method.from_secs_f32 [`Duration::mul_f64`]: https://doc.rust-lang.org/stable/std/time/struct.Duration.html#method.mul_f64 [`Duration::mul_f32`]: https://doc.rust-lang.org/stable/std/time/struct.Duration.html#method.mul_f32 [`Duration::div_f64`]: https://doc.rust-lang.org/stable/std/time/struct.Duration.html#method.div_f64 [`Duration::div_f32`]: https://doc.rust-lang.org/stable/std/time/struct.Duration.html#method.div_f32 [`Duration::div_duration_f64`]: https://doc.rust-lang.org/stable/std/time/struct.Duration.html#method.div_duration_f64 [`Duration::div_duration_f32`]: https://doc.rust-lang.org/stable/std/time/struct.Duration.html#method.div_duration_f32 [`MaybeUninit::as_ptr`]: https://doc.rust-lang.org/stable/std/mem/union.MaybeUninit.html#method.as_ptr [`MaybeUninit::as_mut_ptr`]: https://doc.rust-lang.org/stable/std/mem/union.MaybeUninit.html#method.as_mut_ptr [`MaybeUninit::assume_init`]: https://doc.rust-lang.org/stable/std/mem/union.MaybeUninit.html#method.assume_init [`MaybeUninit::assume_init_ref`]: https://doc.rust-lang.org/stable/std/mem/union.MaybeUninit.html#method.assume_init_ref
This stabilizes the
MaybeUninit::as_ptr
,MaybeUninit::assume_init
, andMaybeUninit::assume_init_ref
asconst fn
.MaybeUninit::as_mut_ptr
has been moved to a new flag:const_maybe_uninit_as_mut_ptr
, which is blocked on #57349.MaybeUninit::slice_assume_init_ref
can beconst fn
when the method is stabilized in general.The relevant intrinsic has been stabilized as
const
as well, though this isn't user-visible. Due to the seemingly unrelated feature name I performedrg const_assert_type
and found no other instances of it being used.r? @oli-obk
@rustbot label: +A-const-fn +S-waiting-on-review +T-libs-api