Hello and welcome to another issue of This Week in Rust! Rust is a programming language empowering everyone to build reliable and efficient software. This is a weekly summary of its progress and community. Want something mentioned? Tag us at @ThisWeekInRust on Twitter or @ThisWeekinRust on mastodon.social, or send us a pull request. Want to get involved? We love contributions.

This Week in Rust is openly developed on GitHub and archives can be viewed at this-week-in-rust.org. If you find any errors in this week's issue, please submit a PR.

Updates from Rust Community

Official

• 2023 Annual Rust Survey Results
• Rust participates in Google Summer of Code 2024
• Leadership Council March Representative Selections

Foundation

• Save the Date: RustConf 2024 – September 10-13
• Second Security Initiative Report Details Rust Security Advancements

Project/Tooling Updates

• Bevy 0.13
• Bevy XPBD 0.4: Collider Agnosticism, Layer Rework, and Bevy 0.13
• uv: Python packaging in Rust
• git-cliff: What's new in 2.0.0? (highly customizable changelog generator)
• rustc_codegen_gcc: Progress Report #30
• RustRover Q4 2023 Feature Updates Retrospective
• rust-analyzer changelog #221
• Anouncing Stabby 3.0
• argmin_testfunctions 0.2.0: test functions for optimization problems in Rust and Python
• vscode-rustup released: interface with rustup as a VSCode extension
• OpenPGP-card-tools 0.10.0 released. The project provides the oct commandline tool for inspecting, configuring and using OpenPGP card devices such as Nitrokey or Yubikey.
• Rust Client for Timeplus Proton SQL Streaming

Observations/Thoughts

• FuturesUnordered and the order of futures
• Rust Tooling: 8 tools that will increase your productivity
• Writing down my mental model of unsafe
• How can Rust be so fast in the TechEmpower Web Framework Benchmarks?

Rust Walkthroughs

• From 1s to 4ms
• Translating OpenStreetMap data to HTML5 Canvas with Rust and WebAssembly
• macros_rule!
• Implementing JWT Authentication in Rust
• Deploying Axum to Lambda and ECS, using Lambda Web Adapter
• Rust/C++ Interop Part 3 - Cxx
• [FR] Les closures en Rust
• [video] Safe Rust AIN'T SAFE!? (cve-rs)

Miscellaneous

• [video] Release-plz: releasing crates like it's 2023 (RustLab 2023)

Crate of the Week

This week's crate is kind, a helper crate for typed UUIDs.

Thanks to Denys Séguret for the self-suggestion!

Please submit your suggestions and votes for next week!

Call for Testing

An important step for RFC implementation is for people to experiment with the implementation and give feedback, especially before stabilization. The following RFCs would benefit from user testing before moving forward:

• RFC: Checking conditional compilation at compile time
  • Testing steps

If you are a feature implementer and would like your RFC to appear on the above list, add the new call-for-testing label to your RFC along with a comment providing testing instructions and/or guidance on which aspect(s) of the feature need testing.

Call for Participation; projects and speakers

CFP - Projects

Always wanted to contribute to open-source projects but did not know where to start? Every week we highlight some tasks from the Rust community for you to pick and get started!

Some of these tasks may also have mentors available, visit the task page for more information.

• Ockam - Syntax highlighting for fenced code blocks, in command help output, on Linux works
• Ockam - Shut down Worker/Processor if initialization failed
• Ockam - Output for ockam project ticket is improved and information is not opaque
• Hyperswitch - [FEATURE] : add offset field to disputes list
• Hyperswitch - [FEATURE]: addoffset field to mandates list
• Hyperswitch - [FEATURE]: add pagination support for customers list

If you are a Rust project owner and are looking for contributors, please submit tasks here.

CFP - Speakers

Are you a new or experienced speaker looking for a place to share something cool? This section highlights events that are being planned and are accepting submissions to join their event as a speaker.

If you are an event organizer hoping to expand the reach of your event, please submit a link to the submission website through a PR to TWiR.

Updates from the Rust Project

508 pull requests were merged in the last week

• implicitly enable evex512 if avx512 is enabled
• const_mut_refs: allow mutable pointers to statics
• macro_rules: Preserve all metavariable spans in a global side table
• add APIs for fetching foreign items
• add rust.frame-pointers config option
• add more checks for unnamed_fields during HIR analysis
• allow AST and HIR visitors to return ControlFlow
• allow mutable references in const values when they point to no memory
• always evaluate free constants and statics, even if previous errors occurred
• avoid an ICE in diagnostics
• be less confident when dyn suggestion is not checked for object safety
• check normalized call signature for WF in mir typeck
• consider principal trait ref's auto-trait super-traits in dyn upcasting
• continue compilation after check_mod_type_wf errors
• continue compilation even if inherent impl checks fail
• continue reporting remaining errors instead of silently dropping them
• detect when method call on argument could be removed to fulfill failed trait bound
• fix an ICE in the recursion lint
• ignore unsized types when trying to determine the size of the original type
• make ConstPropLint lint run on promoteds
• make async Fn trait kind errors better
• properly deal with weak alias types as self types of impls
• rename ConstPropLint to KnownPanicsLint
• store static initializers in metadata instead of the MIR of statics
• suggest into_iter() when Iterator method called on impl IntoIterator
• trigger unsafe_code lint on invocations of global_asm
• use fulfillment in next trait solver coherence
• miri: implement x86 AVX intrinsics
• optimize delayed_bug handling
• optimize away poison guards when std is built with panic=abort
• overhaul Diagnostic and DiagnosticBuilder
• implement Instant for UEFI
• implement Default for AsciiChar
• store core::str::CharSearcher::utf8_size as u8
• make File::read_to_end less special
• implement NonZero traits generically
• make NonZero::get generic
• make io::BorrowedCursor::advance safe
• make is_nonoverlapping #[inline]
• specialize flattening iterators with only one inner item
• specialize some methods of io::Chain
• rename MaybeUninit::write_slice
• don't use mem::zeroed in vec::IntoIter
• optimize VecDeque::drain for (half-)open ranges
• fix BTreeMap's Cursor::remove_{next,prev}
• add Future and IntoFuture to the 2024 prelude
• hashbrown: inline tweaks to HashTable
• hashbrown: make HashSet::insert return OccupiedEntry
• codegen_gcc: correctly handle --use-system-gcc
• codegen_gcc: implement dummy emit=llvm-ir
• codegen_gcc: use the default rust mangling
• codegen_cranelift: fix simd_select_bitmask on big-endian systems
• codegen_cranelift: fix download hash check on big-endian systems
• cargo add: Ensure users know a feature is being created
• cargo add: Remove inconsistent period
• cargo test: Suggest -- for libtest arguments
• cargo: respect rust-version when generating lockfile
• rustdoc: correctly handle long crate names on mobile
• rustdoc: cross-crate re-exports: correctly render late-bound params in source order even if early-bound params are present
• rustdoc: fix handling of doc_auto_cfg feature for cfg attributes on glob reexport
• rustfmt: fix error trying to format unnormalized UTF8
• format async trait bounds in rustfmt
• add clippy into the known cfg list
• clippy: add new lint deprecated_clippy_cfg_attr
• clippy: case_sensitive_file_extension_comparisons: Don't trigger on digits-only extensions
• clippy: implied_bounds_in_impls: avoid linting on overlapping associated tys
• clippy: incompatible_msrv: allow expressions that come from desugaring
• clippy: new_without_default: Now emits on const fns
• clippy: allow negative literals in redundant_guards
• clippy: check trait items in min_ident_chars
• clippy: default test output conflict handling to error
• clippy: ensure ASM syntax detect global_asm! and asm! only on x86 architectures
• clippy: add check for identical guards in lint match_same_arms
• clippy: make #[allow] work on field for pub_underscore_fields
• clippy: ignore imported items in min_ident_chars
• rust-analyzer: activate on top level Cargo.toml and rust-project.json files
• rust-analyzer: deduplicate references when some of them are in macro expansions
• rust-analyzer: create alias when renaming an import
• rust-analyzer: add non-exhaustive-let diagnostic
• rust-analyzer: add unresolved-ident diagnostic
• rust-analyzer: support multiple tab stops for completions in VSCode
• rust-analyzer: add basic support for become expr/tail calls
• rust-analyzer: don't add \ before {
• rust-analyzer: don't show type mismatches for {unknown} to non-{unknown} mismatches
• rust-analyzer: fix "needless return" diagnostic for trailing item declarations
• rust-analyzer: fix build scripts not being rebuilt in some occasions
• rust-analyzer: fix false positives for "unnecessary else" diagnostic
• rust-analyzer: fix snippets being placed leftwards of where they should be
• rust-analyzer: improve recover on = for record field initializer and pattern
• rust-analyzer: only complete traits in impl .. for
• rust-analyzer: place snippets correctly in multi-edit assists
• rust-analyzer: server hanging up on build script task

Rust Compiler Performance Triage

Relatively few PRs affecting performance, but massive improvements thanks to the update to LLVM 18 (PR #12005), as well as the merging of two related compiler queries (PR #120919) and other small improvements from a rollup (PR #121055).

Triage done by @pnkfelix. Revision range: 74c3f5a1..5af21304

3 Regressions, 1 Improvements, 6 Mixed; 1 of them in rollups 65 artifact comparisons made in total

Full report here

Approved RFCs

Changes to Rust follow the Rust RFC (request for comments) process. These are the RFCs that were approved for implementation this week:

• eRFC: Iterate on and stabilize libtest's programmatic output

Final Comment Period

Every week, the team announces the 'final comment period' for RFCs and key PRs which are reaching a decision. Express your opinions now.

RFCs

• RFC: Make Cargo respect minimum supported Rust version (MSRV) when selecting dependencies

Tracking Issues & PRs

Rust

• [disposition: merge] change equate for binders to not rely on subtyping
• [disposition: merge] Implement RFC 3373: Avoid non-local definitions in functions
• [disposition: merge] Tracking Issue for waker_getters
• [disposition: merge] Stabilize the #[diagnostic] namespace and #[diagnostic::on_unimplemented] attribute
• [disposition: merge] Tracking Issue for cfg-target-abi
• [disposition: merge] make non-PartialEq-typed consts as patterns a hard error
• [disposition: close] Allow ?-converting from Result<T, E> in functions returning Option<Result<T, E>>
• [disposition: merge] Add Read Impl for &Stdin
• [disposition: merge] Make Barrier::new() const
• [disposition: close] Implement Future for Option<F>

New and Updated RFCs

• [new] is operator for pattern-matching and binding

Upcoming Events

Rusty Events between 2024-02-21 - 2024-03-20 🦀

Virtual

• 2024-02-21 | Virtual (Cardiff, UK) | Rust and C++ Cardiff
  • Rust for Rustaceans Book Club: Chapter 2 - Types
• 2024-02-21 | Virtual (Vancouver, BC, CA) | Vancouver Rust
  • Rust Study/Hack/Hang-out
• 2024-02-22 | Virtual (Charlottesville, NC, US) | Charlottesville Rust Meetup
  • Crafting Interpreters in Rust Collaboratively
• 2024-02-27 | Virtual (Dallas, TX, US) | Dallas Rust
  • Last Tuesday
• 2024-02-29 | Virtual (Berlin, DE) | OpenTechSchool Berlin + Rust Berlin
  • Rust Hack and Learn | Mirror: Rust Hack n Learn Meetup | Mirror: Berline.rs page
• 2024-02-29 | Virtual (Charlottesville, NC, US) | Charlottesville Rust Meetup
  • Surfing the Rusty Wireless Waves with the ESP32-C3 Board
• 2024-03-06 | Virtual (Indianapolis, IN, US) | Indy Rust
  • Indy.rs - with Social Distancing
• 2024-03-07 | Virtual (Charlottesville, NC, US) | Charlottesville Rust Meetup
  • Crafting Interpreters in Rust Collaboratively
• 2024-03-12 | Virtual (Dallas, TX, US) | Dallas Rust
  • Second Tuesday
• 2024-03-12 | Hybrid (Virtual + In-person) Munich, DE | Rust Munich
  • Rust Munich 2024 / 1 - hybrid
• 2024-03-14 | Virtual (Berlin, DE) | OpenTechSchool Berlin
  • Web Frontend Co-Learning (online)
• 2024-03-21 | Seattle, WA, US | Seattle Rust User Group
  • Seattle Rust User Group Meetup
• 2024-03-26 | Virtual + In Person (Barcelona, ES) | BcnRust
  • 13th BcnRust Meetup - Stream

Europe

• 2024-02-21 | Lyon, FR | Rust Lyon
  • Rust Lyon Meetup #8
• 2024-02-22 | Aarhus, DK | Rust Aarhus
  • Rust and Talk at Partisia
• 2024-02-29 | Berlin, DE | Rust Berlin
  • Rust and Tell - Season start 2024
• 2024-03-12 | Munich, DE + Virtual | Rust Munich
  • Rust Munich 2024 / 1 - hybrid
• 2024-03-19 | Aarhus, DK | Rust Aarhus
  • Hack Night
• 2024-03-20 | Girona, ES | Rust Girona
  • Introduction to programming Microcontrollers with Rust
• 2024-03-26 | Barcelona, ES + Virtual | BcnRust
  • 13th BcnRust Meetup
• 2024-03-26, 2024-03-28 | London, UK | Rust Nation UK
  • Rust Nation 2024

North America

• 2024-02-21 | Boston, MA, US | Boston Rust Meetup
  • Evening Boston Rust Meetup at Microsoft, February 21
• 2024-02-22 | Mountain View, CA, US | Mountain View Rust Meetup
  • Rust Meetup at Hacker Dojo
• 2024-02-28 | Austin, TX, US | Rust ATX
  • Rust Lunch - Fareground
• 2024-03-07 | Mountain View, CA, US | Mountain View Rust Meetup
  • Rust Meetup at Hacker Dojo

Oceania

• 2024-02-27 | Canberra, ACT, AU | Canberra Rust User Group
  • February Meetup
• 2024-02-27 | Sydney, NSW, AU | Rust Sydney
  • 🦀 spire ⚡ & Quick
• 2024-02-29 | Brisbane, QLD, AU | Rust Brisbane
  • February Meetup
• 2024-03-05 | Auckland, NZ | Rust AKL
  • Rust AKL: Introduction to Embedded Rust + The State of Rust UI

If you are running a Rust event please add it to the calendar to get it mentioned here. Please remember to add a link to the event too. Email the Rust Community Team for access.

Jobs

Please see the latest Who's Hiring thread on r/rust

Quote of the Week

Shared mutable state is evil, and you can solve it by forbidding mutation, or by forbidding sharing. Rust supports both.

– kornel on Lobste.rs

Thanks to Aleksey Kladov for the suggestion!

Please submit quotes and vote for next week!

This Week in Rust is edited by: nellshamrell, llogiq, cdmistman, ericseppanen, extrawurst, andrewpollack, U007D, kolharsam, joelmarcey, mariannegoldin, bennyvasquez.

Email list hosting is sponsored by The Rust Foundation

Discuss on r/rust