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 X(formerly 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.

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Updates from Rust Community

Official

• crates.io: development update
• Announcing Rust 1.80.0

Foundation

• Q2 2024 Recap from Rebecca Rumbul
• Welcoming Infrastructure Engineer, Marco Ieni to the Rust Foundation Team

Project/Tooling Updates

• This month in Servo: console logging, parallel tables, OpenXR, and more!
• Copper is Out!
• rust-analyzer changelog #244
• SBOM support in Rust
• pixi - system package manager written in Rust now also supports WASM
• How to do named function arguments in Rust. Introducing bon crate
• Maelstrom 0.11.0: Fast, Clustered, Test Runner -- Now With a New UI
• Rustic Witcher goes open source

Observations/Thoughts

• Don't Use Preludes And Globs
• Async Rust Challenges in Iroh
• repr(C): Clear, Simple and (Sometimes) Wrong
• Once Upon a Lazy Init
• [video] Rust 1.80.0: Top 10 Most Interesting Things & Blog Highlights
• [video] Rust can Compete with Python
• [video] Rust's second most complicated feature explained
• [audio] Rob Ede – Actix Web, Life as an Open Source Maintainer, Supply-chain Security
• [audio] System76 with Jeremy Soller
• [audio] Full-stack development of a B2B payment infrastructure in Rust, with Florent Bécart

Rust Walkthroughs

• Crafting Interpreters with Rust: On Garbage Collection
• Making games play themselves with Rust Part 2: Parsing the Game State
• Why you should use Rust on the backend
• Debugging distributed database mysteries with Rust, packet capture and Polars

Miscellaneous

• Translating All C TO Rust (TRACTOR)
• Rust wins the SIGPLAN Programming Language Software Award 2024

Crate of the Week

This week's crates are static-keys, a nightly-only mechanism to speed up checks of rarely changed features and bon, yet another crate to autogenerate builders from functions, methods and structs.

Thanks to EvianZhang and Veetaha for the suggestions!

Please submit your suggestions and votes for next week!

Calls 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:

RFCs

• No calls for testing were issued this week.

Rust

• No calls for testing were issued this week.

Rustup

• No calls for testing were issued this week.

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.

• greptimedb - Improve Error Messages
• greptimedb - Remove QueryRequest from GreptimeRequest
• greptimedb - Merge small IO to optimize for cloud storage

If you are a Rust project owner and are looking for contributors, please submit tasks here or through a PR to TWiR or by reaching out on X (Formerly twitter) or Mastodon!

CFP - Events

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.

No Calls for papers or presentations were submitted this week.

If you are an event organizer hoping to expand the reach of your event, please submit a link to the website through a PR to TWiR or by reaching out on X (Formerly twitter) or Mastodon!

Updates from the Rust Project

434 pull requests were merged in the last week

• compiler: replace ASCII control chars with Unicode Control Pictures
• #[naked]: report incompatible attributes
• #[naked]: use an allowlist for allowed options on asm! in naked functions
• add NuttX based targets for RISC-V and ARM
• add select_unpredictable to force LLVM to use CMOV
• add a label to point to the lacking macro name definition
• add basic Serde serialization capabilities to Stable MIR
• add migration lint for 2024 prelude additions
• always set result during finish() in debug builders
• bootstrap command refactoring: make command output API more bulletproof (step 7)
• build-manifest: allow building manifests for formats that only have xz compression
• compiler: never debug_assert in codegen
• do not try to reveal hidden types when trying to prove auto-traits in the defining scope
• do not use global caches if opaque types can be defined
• don't ICE if HIR and middle types disagree in borrowck error reporting
• don't ICE when auto trait has assoc ty in old solver
• don't ICE when encountering error regions when confirming object method candidate
• don't elaborate associated types with Sized bounds in trait_object_ty in cfi
• don't manually implement PartialEq for some types in rustc_type_ir
• don't record trait aliases as marker traits
• exhaustiveness: explain why a given pattern is considered unreachable
• extend rules of dead code analysis for impls for adts to impls for types refer to adts
• fix a span error when parsing a wrong param of function
• fix malformed suggestion for repeated maybe unsized bounds
• fix supertrait associated type unsoundness
• fix: UWP compilation issue with change_time refactored type
• graciously handle Drop impls introducing more generic parameters than the ADT
• handle no_std targets on std builds
• implement Copy/Clone for async closures
• implement lint against ambiguous negative literals
• improve extern "<abi>" unsafe fn() error message
• improve error message when global_asm! uses asm! options
• improve spans on evaluated cfg_attrs
• inject arm32 shims into Windows metadata generation
• isolate the diagnostic code that expects thir::Pat to be printable
• let InstCombine remove Clone shims inside Clone shims
• make missing_fragment_specifier an error in edition 2024
• make sure that args are compatible in resolve_associated_item
• mark missing_fragment_specifier as FutureReleaseErrorReportInDeps
• match exhaustiveness: Expand or-patterns as a separate step
• note closure captures when reporting cast to fn ptr failed
• perform instsimplify before inline to eliminate some trivial calls
• skip assoc type during infer source visitor
• stop using unsized_const_parameters in core/std
• support ?Trait bounds in supertraits and dyn Trait under a feature gate
• support lists and stylings in more places for rustc --explain
• tweak "wrong # of generics" suggestions
• miri: add flock shim
• miri: add gettid support
• miri: fix offset_from behavior on wildcard pointers
• miri: better diagnostics for Tree Borrows + int2ptr casts
• miri: show warning when Stacked Borrows skips a reborrow due to 'extern type'
• stabilize const_waker
• stabilize is_sorted
• stabilize offset_of_nested
• stabilize const {integer}::from_str_radix i.e. const_int_from_str
• initial implementation of anonymous_pipe API
• add elem_offset and related methods
• add is_multiple_of for unsigned integer types
• implement unsigned_signed_diff
• allow optimizing u32::from::<char>
• bitwise and bytewise methods on NonZero
• implement unsigned_signed_diff
• optimize empty case in Vec::retain
• remove generic lifetime parameter of trait Pattern
• replace io::Cursor::{remaining_slice, is_empty}
• cargo: dont call wrap in a no-op source_id::with*
• cargo: fix: remove rustc probe for --check-cfg support
• cargo: package workspaces
• rustdoc: Add copy code feature
• rustdoc: change title of search results
• rustdoc: use strategic ThinVec/Box to shrink clean::ItemKind
• rustdoc: word wrap CamelCase in the item list table and sidebar
• rustfmt: implement Style Edition support
• rustfmt: modify ListItem to hold RewriteResult as the item field
• rustfmt: track configs set from cli flags
• clippy: missing_trait_methods: lint methods in definition order
• clippy: needless_borrows_for_generic_args: Fix for &mut
• clippy: add BTreeSet detection to the set_contains_or_insert lint
• clippy: add possibility to focus on search input using keyboard
• clippy: emit if_let_mutex in presence of other mutexes
• clippy: fix while_let_on_iterator dropping loop label when applying fix
• clippy: fix display of configs in clippy doc page
• clippy: fix under loop may dropping loop label when applying fix
• clippy: fix handling of Deref in assigning_clones
• clippy: lint casts to u128 in cast_lossless
• clippy: lintcheck: support underscores replacement in URL crate names
• clippy: make BindInsteadOfMap a struct
• clippy: make std_instead_of_core somewhat MSRV aware
• clippy: make restriction lint's use span_lint_and_then (i → p)
• clippy: suggest .cast/.cast_const/.cast_mut in transmute_ptr_as_ptr
• rust-analyzer: run unit tests at the crate level not workspace
• rust-analyzer: Invalid RA diagnostic error: expected 2 arguments, found 1
• rust-analyzer: add preliminary support for + use<..> precise_capturing syntax
• rust-analyzer: introduce workspace rust-analyzer.tomls
• rust-analyzer: use spans for builtin and declarative macro expansion errors
• rust-analyzer: don't retry inlay hint and cole lens requests
• rust-analyzer: early exit if unresolved field is an index
• rust-analyzer: explictly show async keyword on impl trait methods
• rust-analyzer: fix builtin includes rejecting raw string literals
• rust-analyzer: fix includes not working with expr fragment inputs
• rust-analyzer: let glob imports override other globs' visibility
• rust-analyzer: support new cargo config get env format
• rust-analyzer: flip the naming of the doc comment to comment assist

Rust Compiler Performance Triage

There were some notable regressions this week. Some of them are being addressed via follow-up PRs (such as the change to whitespace diagnostic reporting), and some via reverts (such as the dead code analysis that tried to flag pub structs without pub constructors). A few regressions have not yet been addressed. See report for details.

Triage done by @pnkfelix. Revision range: 9629b90b..7e3a9718

5 Regressions, 6 Improvements, 6 Mixed; 8 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:

• Tracking Issue for float_semantics RFC 3514

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

• [disposition: merge] Async closures
• [disposition: merge] Add named path bases to cargo (v2)
• [disposition: merge] CPU feature detection in core

Tracking Issues & PRs

Rust

• [disposition: merge] Disallow setting some built-in cfg via set the command-line
• [disposition: merge] Enforce supertrait outlives obligations hold when confirming impl
• [disposition: merge] impl Default for collection iterators that don't already have it
• [disposition: merge] turn invalid_type_param_default into a FutureReleaseErrorReportInDeps
• [disposition: merge] Stabilize unsafe extern blocks (RFC 3484)
• [disposition: merge] Tracking Issue for std::ffi::c_str module

Cargo

• [disposition: merge] feat: Add info cargo subcommand

Language Team

• No Language Team Tracking Issues or PRs entered Final Comment Period this week.

Language Reference

• No Language Reference RFCs entered Final Comment Period this week.

Unsafe Code Guidelines

• No Unsafe Code Guideline Tracking Issues or PRs entered Final Comment Period this week.

New and Updated RFCs

• No New or Updated RFCs were created this week.

Upcoming Events

Rusty Events between 2024-07-31 - 2024-08-28 🦀

Virtual

• 2024-07-31 | Virtual (Tel Aviv, IL) | Code Mavens
  • Command Line Tools: Implementing wc in Rust (English, Virtual)
• 2024-08-01 | Virtual (Berlin, DE) | OpenTechSchool Berlin + Rust Berlin
  • Rust Hack and Learn | Mirror: Rust Hack n Learn Meetup
• 2024-08-06 | Virtual | Women in Rust
  • Lunch & Learn! (Virtual)
• 2024-08-06 | Virtual (Buffalo, NY, US) | Buffalo Rust Meetup
  • Buffalo Rust User Group
• 2024-08-06 | Virtual (Tel Aviv, IL) | Code Mavens
  • Web development in Rust using Rocket - part 2 (English)
• 2024-08-07 | Virtual (Indianapolis, IN, US) | Indy Rust
  • Indy.rs - with Social Distancing
• 2024-08-08 | Virtual (Charlottesville, NC, US) | Charlottesville Rust Meetup
  • Crafting Interpreters in Rust Collaboratively
• 2024-08-08 | Virtual (Nürnberg, DE) | Rust Nuremberg
  • Rust Nürnberg online
• 2024-08-08 | Virtual (Tel Aviv, IL) | Code Mavens
  • Rust Source Code Reading: The thousands crate (English)
• 2024-08-13 | Virtual (Dallas, TX, US) | Dallas Rust
  • Second Tuesday
• 2024-08-15 | Virtual (Berlin, DE) | OpenTechSchool Berlin + Rust Berlin
  • Rust Hack and Learn | Mirror: Rust Hack n Learn Meetup
• 2024-08-20 | Virtual (Washington, DC, US) | Rust DC
  • Mid-month Rustful
• 2024-08-21 | Hybrid - Virtual and In-Person (Vancouver, BC, CA) | Vancouver Rust
  • Rust Study/Hack/Hang-out
• 2024-08-22 | Virtual (Charlottesville, NC, US) | Charlottesville Rust Meetup
  • Crafting Interpreters in Rust Collaboratively
• 2024-08-27 | Virtual | Ardan Labs
  • Fearless Concurrency with Rust
• 2024-08-27 | Virtual (Dallas, TX, US) | Dallas Rust
  • Last Tuesday

Africa

• 2024-08-02 | Kampala, UG | Rust Circle Kampala
  • Rust Circle Meetup

Europe

• 2024-08-14 | Reading, UK | Reading Rust Workshop
  • Reading Rust Meetup
• 2024-08-20 | Aarhus, DK | Rust Aarhus
  • Hack Night
• 2024-08-21 | Nürnberg, DE | Rust Nuremberg
  • Walk'n'Talk around Wöhrder See (+ Burritos)
• 2024-08-26 | Mainz, DE | Fachschaft Mathematik+Informatik der JGU Mainz
  • Ferienkurs Rust

North America

• 2024-08-01 | St. Louis, MO, US | STL Rust
  • Lifetimes
• 2024-08-08 | Mountain View, CA, US | Mountain View Rust Meetup
  • Rust Meetup at Hacker Dojo
• 2024-08-08 | Seattle, WA, US | Seattle Rust User Group
  • August Meetup
• 2024-08-19 | Minneapolis, MN US | Minneapolis Rust Meetup
  • Minneapolis Rust Meetup: "State of Rust GPU Programming" & Happy Hour
• 2024-08-20 | New York, NY, US | Rust NYC
  • Rust NYC: Doing the Bare Minimum with Isograph (talk)
• 2024-08-20 | San Francisco, CA, US | San Francisco Rust Study Group
  • Rust Hacking in Person
• 2024-08-21 | Virtual and In-Person (Vancouver, BC, CA) | Vancouver Rust
  • Rust Study/Hack/Hang-out
• 2024-08-28 | Austin, TX, US | Rust ATC
  • Rust Lunch - Fareground

Oceania

• 2024-08-01 | Brisbane, QLD, AU | Rust Brisbane
  • August Meetup
• 2024-08-27 | Canberra, ACT, AU | Canberra Rust User Group (CRUG)
  • June Meetup

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

Man, rust crates are so allergic to 1.0 that they'll skip all the way to version 22.

– /u/darkpyro2 on /r/rust

Thanks to Erich Gubler 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.

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Discuss on r/rust