Consider `#[must_use]` annotation on `async fn` as also affecting the `Future::Output` #100633

estebank · 2022-08-16T14:58:32Z

No longer lint against #[must_use] async fn foo().

When encountering a statement that awaits on a Future, check if the
Future's parent item is annotated with #[must_use] and emit a lint
if so. This effectively makes must_use an annotation on the
Future::Output instead of only the Future itself.

Fix #78149.

rust-highfive · 2022-08-16T14:58:35Z

r? @compiler-errors

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

estebank · 2022-08-16T14:59:30Z

cc @rust-lang/wg-async

estebank · 2022-08-16T14:59:48Z

r? rust-lang/wg-async

compiler-errors · 2022-08-16T23:25:29Z

There's no wg-async high-five list, and I think @spastorino is the only wg-async member who is on the high-five queue. Feel free to reassign back to me -- happy to review this since it's basically just diagnostics.

r? @spastorino

tmandry · 2022-08-17T00:31:29Z

Wow, I was just thinking about this! I volunteer as tribute.

r? @tmandry

tmandry

I think this is a very good approach that gets us a useful lint without boiling the ocean. It doesn't solve all problems (like going through join! or similar), but that's allowed ("Trivial no-op expressions containing the value will not violate the lint").

It might actually be possible to support more of those cases by examining any pattern match, not just from matches desugared awaits. But if that's not easy (or too slow) we should land this now and leave it as follow-up work.

@rustbot author

compiler/rustc_lint/src/unused.rs

compiler/rustc_passes/src/check_attr.rs

src/test/ui/lint/unused/unused-async.stderr

tmandry · 2022-08-17T01:04:47Z

src/test/ui/lint/unused/unused-async.rs

    1
 }

+#[must_use]
+fn bar() -> impl std::future::Future<Output=i32> {


I actually think this might have bigger lang implications, like implying this should also work for functions returning Result as mentioned by #78149 (comment) or on associated types of other traits.

Do you think we should restrict to only async fn for now? (I don't really want to do that since it limits the usefulness of the PR, but we might want the lang team to weigh in otherwise.)

Yeah, I think we should limit this to just async fn's for now. Generalizing #[must_use] to look through types like Result and Future is going to require, I think, a pretty significant change (I think niko and I talked about basically needing auto-trait semantics?), and we should probably hold off on any half-measures that may make that more difficult (unless we decide its too difficult)

Stopping this from working would require changing the FnDecl representation of all functions with information about the asyncness. Right now that is only tracked up to the HIR. I could make the lint check the fn item to see if it's async or not, but that only works for functions of the local crate. The four options here are: what it does now, and always propagate must_use from any fn to the Future::Output it might return, make must_use on async fn only work for local crates, make must_use on fns always work for foreign crates but only for async fn in local crates, or modify ty::FnDecl to track more metadata. I'm leaning towards the first case, despite the incorrect mental model it might imply to users for Result and Option.

Did not realize the complexity here! In that case, its probably fine to leave it! The plus side is that future work could make things like

#[must_use] fn thing() -> BoxFuture<Thing> { ... }

can apply to Thing!

I tend to agree, but I also don't know if I should be approving decisions about where a lint applies. I started a Zulip thread to get some t-lang feedback first.

src/test/ui/lint/unused/unused-async.rs

src/test/ui/lint/unused/unused-async.stderr

tmandry · 2022-08-19T01:19:19Z

@rustbot label +I-lang-nominated

Lang team, are you ok with expanding the meaning of #[must_use] on both of the following?

#[must_use] async fn foo() -> T
#[must_use] fn foo() -> impl Future<Output = T>

In each case the target of the attribute is T.

I think this is a win for users (and doing otherwise would be a potential performance/implementation headache), but it relates to some questions about how it might interact with future expansions of #[must_use].

#[must_use] fn foo() -> F where F: Future<Output = T>
Generalizing to other traits marked #[must_use]
Generalizing to #[must_use] wrapper types, like Result<T, E>
Finding a solution that works for e.g. Option<T> (not must_use)

See this #t-lang thread for more context.

bors · 2022-08-21T13:34:07Z

☔ The latest upstream changes (presumably #100765) made this pull request unmergeable. Please resolve the merge conflicts.

pnkfelix · 2022-08-30T18:45:46Z

@rustbot label: -T-compiler +T-lang

pnkfelix · 2022-08-30T18:45:56Z

@rfcbot fcp merge

rfcbot · 2022-08-30T18:45:57Z

Team member @pnkfelix 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.

shengsheng · 2022-11-11T00:40:16Z

@estebank We have the "S-waiting-on-bors" label, but "This branch has conflicts that must be resolved", Could you please rebase this pr?

Do not point at whole statement, only at the expression (skip pointing at `;`)

… `Future::Output` No longer lint against `#[must_use] async fn foo()`. When encountering a statement that awaits on a `Future`, check if the `Future`'s parent item is annotated with `#[must_use]` and emit a lint if so. This effectively makes `must_use` an annotation on the `Future::Output` instead of only the `Future` itself. Fix rust-lang#78149.

estebank · 2022-11-11T02:07:55Z

@bors r=tmandry

bors · 2022-11-11T02:07:57Z

📌 Commit 8bd8484 has been approved by tmandry

It is now in the queue for this repository.

estebank · 2022-11-11T03:01:59Z

@bors r=tmandry

bors · 2022-11-11T03:02:00Z

📌 Commit f57713b has been approved by tmandry

It is now in the queue for this repository.

… r=tmandry Consider `#[must_use]` annotation on `async fn` as also affecting the `Future::Output` No longer lint against `#[must_use] async fn foo()`. When encountering a statement that awaits on a `Future`, check if the `Future`'s parent item is annotated with `#[must_use]` and emit a lint if so. This effectively makes `must_use` an annotation on the `Future::Output` instead of only the `Future` itself. Fix rust-lang#78149.

Rollup of 9 pull requests Successful merges: - rust-lang#100633 (Consider `#[must_use]` annotation on `async fn` as also affecting the `Future::Output`) - rust-lang#103445 (`#[test]`: Point at return type if `Termination` bound is unsatisfied) - rust-lang#103924 (Fix broken link in description of error code E0706) - rust-lang#104146 (Retry binding TCP Socket in remote-test-server) - rust-lang#104169 (Migrate `:target` rules to use CSS variables) - rust-lang#104202 (Fix ICE rust-lang#103748) - rust-lang#104216 (Don't ICE on operator trait methods with generic methods) - rust-lang#104217 (Display help message when fluent arg was referenced incorrectly) - rust-lang#104245 (Reduce default configuration's dependency upon static libstdcpp library (rust-lang#103606)) Failed merges: r? `@ghost` `@rustbot` modify labels: rollup

Pkgsrc changes: * Adjust patches and cargo checksums to new versions, but also one strange "mips" conditional. Upstream changes: Version 1.67.0 (2023-01-26) ========================== Language -------- - [Make `Sized` predicates coinductive, allowing cycles.] (rust-lang/rust#100386) - [`#[must_use]` annotations on `async fn` also affect the `Future::Output`.] (rust-lang/rust#100633) - [Elaborate supertrait obligations when deducing closure signatures.] (rust-lang/rust#101834) - [Invalid literals are no longer an error under `cfg(FALSE)`.] (rust-lang/rust#102944) - [Unreserve braced enum variants in value namespace.] (rust-lang/rust#103578) Compiler -------- - [Enable varargs support for calling conventions other than `C` or `cdecl`.] (rust-lang/rust#97971) - [Add new MIR constant propagation based on dataflow analysis.] (rust-lang/rust#101168) - [Optimize field ordering by grouping m\*2^n-sized fields with equivalently aligned ones.] (rust-lang/rust#102750) - [Stabilize native library modifier `verbatim`.] (rust-lang/rust#104360) Added and removed targets: - [Add a tier 3 target for PowerPC on AIX] (rust-lang/rust#102293), `powerpc64-ibm-aix`. - [Add a tier 3 target for the Sony PlayStation 1] (rust-lang/rust#102689), `mipsel-sony-psx`. - [Add tier 3 `no_std` targets for the QNX Neutrino RTOS] (rust-lang/rust#102701), `aarch64-unknown-nto-qnx710` and `x86_64-pc-nto-qnx710`. - [Remove tier 3 `linuxkernel` targets] (rust-lang/rust#104015) (not used by the actual kernel). Refer to Rust's [platform support page][platform-support-doc] for more information on Rust's tiered platform support. Libraries --------- - [Merge `crossbeam-channel` into `std::sync::mpsc`.] (rust-lang/rust#93563) - [Fix inconsistent rounding of 0.5 when formatted to 0 decimal places.] (rust-lang/rust#102935) - [Derive `Eq` and `Hash` for `ControlFlow`.] (rust-lang/rust#103084) - [Don't build `compiler_builtins` with `-C panic=abort`.] (rust-lang/rust#103786) Stabilized APIs --------------- - [`{integer}::checked_ilog`] (https://doc.rust-lang.org/stable/std/primitive.i32.html#method.checked_ilog) - [`{integer}::checked_ilog2`] (https://doc.rust-lang.org/stable/std/primitive.i32.html#method.checked_ilog2) - [`{integer}::checked_ilog10`] (https://doc.rust-lang.org/stable/std/primitive.i32.html#method.checked_ilog10) - [`{integer}::ilog`] (https://doc.rust-lang.org/stable/std/primitive.i32.html#method.ilog) - [`{integer}::ilog2`] (https://doc.rust-lang.org/stable/std/primitive.i32.html#method.ilog2) - [`{integer}::ilog10`] (https://doc.rust-lang.org/stable/std/primitive.i32.html#method.ilog10) - [`NonZeroU*::ilog2`] (https://doc.rust-lang.org/stable/std/num/struct.NonZeroU32.html#method.ilog2) - [`NonZeroU*::ilog10`] (https://doc.rust-lang.org/stable/std/num/struct.NonZeroU32.html#method.ilog10) - [`NonZero*::BITS`] (https://doc.rust-lang.org/stable/std/num/struct.NonZeroU32.html#associatedconstant.BITS) These APIs are now stable in const contexts: - [`char::from_u32`] (https://doc.rust-lang.org/stable/std/primitive.char.html#method.from_u32) - [`char::from_digit`] (https://doc.rust-lang.org/stable/std/primitive.char.html#method.from_digit) - [`char::to_digit`] (https://doc.rust-lang.org/stable/std/primitive.char.html#method.to_digit) - [`core::char::from_u32`] (https://doc.rust-lang.org/stable/core/char/fn.from_u32.html) - [`core::char::from_digit`] (https://doc.rust-lang.org/stable/core/char/fn.from_digit.html) Compatibility Notes ------------------- - [The layout of `repr(Rust)` types now groups m\*2^n-sized fields with equivalently aligned ones.] (rust-lang/rust#102750) This is intended to be an optimization, but it is also known to increase type sizes in a few cases for the placement of enum tags. As a reminder, the layout of `repr(Rust)` types is an implementation detail, subject to change. - [0.5 now rounds to 0 when formatted to 0 decimal places.] (rust-lang/rust#102935) This makes it consistent with the rest of floating point formatting that rounds ties toward even digits. - [Chains of `&&` and `||` will now drop temporaries from their sub-expressions in evaluation order, left-to-right.] (rust-lang/rust#103293) Previously, it was "twisted" such that the _first_ expression dropped its temporaries _last_, after all of the other expressions dropped in order. - [Underscore suffixes on string literals are now a hard error.] (rust-lang/rust#103914) This has been a future-compatibility warning since 1.20.0. - [Stop passing `-export-dynamic` to `wasm-ld`.] (rust-lang/rust#105405) - [`main` is now mangled as `__main_void` on `wasm32-wasi`.] (rust-lang/rust#105468) - [Cargo now emits an error if there are multiple registries in the configuration with the same index URL.] (rust-lang/cargo#10592) 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. - [Rewrite LLVM's archive writer in Rust.] (rust-lang/rust#97485)

Mini-fix `double_must_use` for async functions From Rust 1.67 onwards, the `#[must_use]` attribute also applies to the `Future::Output` (rust-lang/rust#100633). So the lint `double_must_use` was linting all async functions. This PR changes the `double_must_use` lint so it ignores `async` functions. --- Closes #10486 changelog: [`double_must_use`]: Fix false positive in async function

Pkgsrc changes: * Adjust patches (add & remove) and cargo checksums to new versions. * It's conceivable that the workaround for LLVM based NetBSD works even less in this version (ref. PKGSRC_HAVE_LIBCPP not having a corresponding patch anymore). Upstream changes: Version 1.68.2 (2023-03-28) =========================== - [Update the GitHub RSA host key bundled within Cargo] (rust-lang/cargo#11883). The key was [rotated by GitHub] (https://github.blog/2023-03-23-we-updated-our-rsa-ssh-host-key/) on 2023-03-24 after the old one leaked. - [Mark the old GitHub RSA host key as revoked] (rust-lang/cargo#11889). This will prevent Cargo from accepting the leaked key even when trusted by the system. - [Add support for `@revoked` and a better error message for `@cert-authority` in Cargo's SSH host key verification] (rust-lang/cargo#11635) Version 1.68.1 (2023-03-23) =========================== - [Fix miscompilation in produced Windows MSVC artifacts] (rust-lang/rust#109094) This was introduced by enabling ThinLTO for the distributed rustc which led to miscompilations in the resulting binary. Currently this is believed to be limited to the -Zdylib-lto flag used for rustc compilation, rather than a general bug in ThinLTO, so only rustc artifacts should be affected. - [Fix --enable-local-rust builds] (rust-lang/rust#109111) - [Treat `$prefix-clang` as `clang` in linker detection code] (rust-lang/rust#109156) - [Fix panic in compiler code] (rust-lang/rust#108162) Version 1.68.0 (2023-03-09) =========================== Language -------- - [Stabilize default_alloc_error_handler] (rust-lang/rust#102318) This allows usage of `alloc` on stable without requiring the definition of a handler for allocation failure. Defining custom handlers is still unstable. - [Stabilize `efiapi` calling convention.] (rust-lang/rust#105795) - [Remove implicit promotion for types with drop glue] (rust-lang/rust#105085) Compiler -------- - [Change `bindings_with_variant_name` to deny-by-default] (rust-lang/rust#104154) - [Allow .. to be parsed as let initializer] (rust-lang/rust#105701) - [Add `armv7-sony-vita-newlibeabihf` as a tier 3 target] (rust-lang/rust#105712) - [Always check alignment during compile-time const evaluation] (rust-lang/rust#104616) - [Disable "split dwarf inlining" by default.] (rust-lang/rust#106709) - [Add vendor to Fuchsia's target triple] (rust-lang/rust#106429) - [Enable sanitizers for s390x-linux] (rust-lang/rust#107127) Libraries --------- - [Loosen the bound on the Debug implementation of Weak.] (rust-lang/rust#90291) - [Make `std::task::Context` !Send and !Sync] (rust-lang/rust#95985) - [PhantomData layout guarantees] (rust-lang/rust#104081) - [Don't derive Debug for `OnceWith` & `RepeatWith`] (rust-lang/rust#104163) - [Implement DerefMut for PathBuf] (rust-lang/rust#105018) - [Add O(1) `Vec -> VecDeque` conversion guarantee] (rust-lang/rust#105128) - [Leak amplification for peek_mut() to ensure BinaryHeap's invariant is always met] (rust-lang/rust#105851) Stabilized APIs --------------- - [`{core,std}::pin::pin!`] (https://doc.rust-lang.org/stable/std/pin/macro.pin.html) - [`impl From<bool> for {f32,f64}`] (https://doc.rust-lang.org/stable/std/primitive.f32.html#impl-From%3Cbool%3E-for-f32) - [`std::path::MAIN_SEPARATOR_STR`] (https://doc.rust-lang.org/stable/std/path/constant.MAIN_SEPARATOR_STR.html) - [`impl DerefMut for PathBuf`] (https://doc.rust-lang.org/stable/std/path/struct.PathBuf.html#impl-DerefMut-for-PathBuf) These APIs are now stable in const contexts: - [`VecDeque::new`] (https://doc.rust-lang.org/stable/std/collections/struct.VecDeque.html#method.new) Cargo ----- - [Stabilize sparse registry support for crates.io] (rust-lang/cargo#11224) - [`cargo build --verbose` tells you more about why it recompiles.] (rust-lang/cargo#11407) - [Show progress of crates.io index update even `net.git-fetch-with-cli` option enabled] (rust-lang/cargo#11579) Misc ---- Compatibility Notes ------------------- - [Add `SEMICOLON_IN_EXPRESSIONS_FROM_MACROS` to future-incompat report] (rust-lang/rust#103418) - [Only specify `--target` by default for `-Zgcc-ld=lld` on wasm] (rust-lang/rust#101792) - [Bump `IMPLIED_BOUNDS_ENTAILMENT` to Deny + ReportNow] (rust-lang/rust#106465) - [`std::task::Context` no longer implements Send and Sync] (rust-lang/rust#95985) nternal 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. - [Encode spans relative to the enclosing item] (rust-lang/rust#84762) - [Don't normalize in AstConv] (rust-lang/rust#101947) - [Find the right lower bound region in the scenario of partial order relations] (rust-lang/rust#104765) - [Fix impl block in const expr] (rust-lang/rust#104889) - [Check ADT fields for copy implementations considering regions] (rust-lang/rust#105102) - [rustdoc: simplify JS search routine by not messing with lev distance] (rust-lang/rust#105796) - [Enable ThinLTO for rustc on `x86_64-pc-windows-msvc`] (rust-lang/rust#103591) - [Enable ThinLTO for rustc on `x86_64-apple-darwin`] (rust-lang/rust#103647) Version 1.67.0 (2023-01-26) ========================== Language -------- - [Make `Sized` predicates coinductive, allowing cycles.] (rust-lang/rust#100386) - [`#[must_use]` annotations on `async fn` also affect the `Future::Output`.] (rust-lang/rust#100633) - [Elaborate supertrait obligations when deducing closure signatures.] (rust-lang/rust#101834) - [Invalid literals are no longer an error under `cfg(FALSE)`.] (rust-lang/rust#102944) - [Unreserve braced enum variants in value namespace.] (rust-lang/rust#103578) Compiler -------- - [Enable varargs support for calling conventions other than `C` or `cdecl`.] (rust-lang/rust#97971) - [Add new MIR constant propagation based on dataflow analysis.] (rust-lang/rust#101168) - [Optimize field ordering by grouping m\*2^n-sized fields with equivalently aligned ones.] (rust-lang/rust#102750) - [Stabilize native library modifier `verbatim`.] (rust-lang/rust#104360) Added and removed targets: - [Add a tier 3 target for PowerPC on AIX] (rust-lang/rust#102293), `powerpc64-ibm-aix`. - [Add a tier 3 target for the Sony PlayStation 1] (rust-lang/rust#102689), `mipsel-sony-psx`. - [Add tier 3 `no_std` targets for the QNX Neutrino RTOS] (rust-lang/rust#102701), `aarch64-unknown-nto-qnx710` and `x86_64-pc-nto-qnx710`. - [Remove tier 3 `linuxkernel` targets] (rust-lang/rust#104015) (not used by the actual kernel). Refer to Rust's [platform support page][platform-support-doc] for more information on Rust's tiered platform support. Libraries --------- - [Merge `crossbeam-channel` into `std::sync::mpsc`.] (rust-lang/rust#93563) - [Fix inconsistent rounding of 0.5 when formatted to 0 decimal places.] (rust-lang/rust#102935) - [Derive `Eq` and `Hash` for `ControlFlow`.] (rust-lang/rust#103084) - [Don't build `compiler_builtins` with `-C panic=abort`.] (rust-lang/rust#103786) Stabilized APIs --------------- - [`{integer}::checked_ilog`] (https://doc.rust-lang.org/stable/std/primitive.i32.html#method.checked_ilog) - [`{integer}::checked_ilog2`] (https://doc.rust-lang.org/stable/std/primitive.i32.html#method.checked_ilog2) - [`{integer}::checked_ilog10`] (https://doc.rust-lang.org/stable/std/primitive.i32.html#method.checked_ilog10) - [`{integer}::ilog`] (https://doc.rust-lang.org/stable/std/primitive.i32.html#method.ilog) - [`{integer}::ilog2`] (https://doc.rust-lang.org/stable/std/primitive.i32.html#method.ilog2) - [`{integer}::ilog10`] (https://doc.rust-lang.org/stable/std/primitive.i32.html#method.ilog10) - [`NonZeroU*::ilog2`] (https://doc.rust-lang.org/stable/std/num/struct.NonZeroU32.html#method.ilog2) - [`NonZeroU*::ilog10`] (https://doc.rust-lang.org/stable/std/num/struct.NonZeroU32.html#method.ilog10) - [`NonZero*::BITS`] (https://doc.rust-lang.org/stable/std/num/struct.NonZeroU32.html#associatedconstant.BITS) These APIs are now stable in const contexts: - [`char::from_u32`] (https://doc.rust-lang.org/stable/std/primitive.char.html#method.from_u32) - [`char::from_digit`] (https://doc.rust-lang.org/stable/std/primitive.char.html#method.from_digit) - [`char::to_digit`] (https://doc.rust-lang.org/stable/std/primitive.char.html#method.to_digit) - [`core::char::from_u32`] (https://doc.rust-lang.org/stable/core/char/fn.from_u32.html) - [`core::char::from_digit`] (https://doc.rust-lang.org/stable/core/char/fn.from_digit.html) Compatibility Notes ------------------- - [The layout of `repr(Rust)` types now groups m\*2^n-sized fields with equivalently aligned ones.] (rust-lang/rust#102750) This is intended to be an optimization, but it is also known to increase type sizes in a few cases for the placement of enum tags. As a reminder, the layout of `repr(Rust)` types is an implementation detail, subject to change. - [0.5 now rounds to 0 when formatted to 0 decimal places.] (rust-lang/rust#102935) This makes it consistent with the rest of floating point formatting that rounds ties toward even digits. - [Chains of `&&` and `||` will now drop temporaries from their sub-expressions in evaluation order, left-to-right.] (rust-lang/rust#103293) Previously, it was "twisted" such that the _first_ expression dropped its temporaries _last_, after all of the other expressions dropped in order. - [Underscore suffixes on string literals are now a hard error.] (rust-lang/rust#103914) This has been a future-compatibility warning since 1.20.0. - [Stop passing `-export-dynamic` to `wasm-ld`.] (rust-lang/rust#105405) - [`main` is now mangled as `__main_void` on `wasm32-wasi`.] (rust-lang/rust#105468) - [Cargo now emits an error if there are multiple registries in the configuration with the same index URL.] (rust-lang/cargo#10592) 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. - [Rewrite LLVM's archive writer in Rust.] (rust-lang/rust#97485)

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estebank force-pushed the must_use_async_fn_return branch from 76c05d7 to e719b0a Compare August 18, 2022 11:58

rustbot added the I-lang-nominated Nominated for discussion during a lang team meeting. label Aug 19, 2022

joshtriplett removed the I-lang-nominated Nominated for discussion during a lang team meeting. label Aug 30, 2022

rustbot added T-lang Relevant to the language team, which will review and decide on the PR/issue. and removed T-compiler Relevant to the compiler team, which will review and decide on the PR/issue. labels Aug 30, 2022

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 Aug 30, 2022

estebank added 3 commits November 10, 2022 18:01

Tweak span for #[must_use]

50bb7a4

Do not point at whole statement, only at the expression (skip pointing at `;`)

review comments

8bd8484

estebank force-pushed the must_use_async_fn_return branch from e719b0a to 8bd8484 Compare November 11, 2022 02:07

Fix tests after rebase

f57713b

Manishearth mentioned this pull request Nov 11, 2022

Rollup of 10 pull requests #104270

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Manishearth mentioned this pull request Nov 11, 2022

Rollup of 9 pull requests #104273

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Dylan-DPC mentioned this pull request Nov 11, 2022

Rollup of 8 pull requests #104275

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Dylan-DPC mentioned this pull request Nov 11, 2022

Rollup of 9 pull requests #104289

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bors merged commit 978e7ab into rust-lang:master Nov 11, 2022

rustbot added this to the 1.67.0 milestone Nov 11, 2022

garryod mentioned this pull request Mar 11, 2023

clippy::double-must-use emitted for #[must_use] on async fn rust-lang/rust-clippy#10486

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blyxyas mentioned this pull request Apr 2, 2023

Mini-fix double_must_use for async functions rust-lang/rust-clippy#10589

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Consider `#[must_use]` annotation on `async fn` as also affecting the `Future::Output` #100633

Consider `#[must_use]` annotation on `async fn` as also affecting the `Future::Output` #100633

estebank commented Aug 16, 2022

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estebank commented Aug 16, 2022

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compiler-errors commented Aug 16, 2022 •

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tmandry commented Aug 17, 2022

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guswynn Aug 17, 2022

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guswynn Aug 17, 2022 •

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tmandry Aug 18, 2022

tmandry commented Aug 19, 2022

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pnkfelix commented Aug 30, 2022

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rfcbot commented Aug 30, 2022 •

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shengsheng commented Nov 11, 2022

estebank commented Nov 11, 2022

bors commented Nov 11, 2022

estebank commented Nov 11, 2022

bors commented Nov 11, 2022

Consider #[must_use] annotation on async fn as also affecting the Future::Output #100633

Consider #[must_use] annotation on async fn as also affecting the Future::Output #100633

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estebank commented Aug 16, 2022

rust-highfive commented Aug 16, 2022

estebank commented Aug 16, 2022

estebank commented Aug 16, 2022

compiler-errors commented Aug 16, 2022 • edited Loading

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tmandry commented Aug 19, 2022

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pnkfelix commented Aug 30, 2022

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rfcbot commented Aug 30, 2022 • edited by pnkfelix Loading

shengsheng commented Nov 11, 2022

estebank commented Nov 11, 2022

bors commented Nov 11, 2022

estebank commented Nov 11, 2022

bors commented Nov 11, 2022

Consider `#[must_use]` annotation on `async fn` as also affecting the `Future::Output` #100633

Consider `#[must_use]` annotation on `async fn` as also affecting the `Future::Output` #100633

compiler-errors commented Aug 16, 2022 •

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tmandry Aug 17, 2022 •

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estebank Aug 17, 2022 •

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guswynn Aug 17, 2022 •

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rfcbot commented Aug 30, 2022 •

edited by pnkfelix

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