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

Foundation

• Announcing the Rust Foundation’s 2024 Fellows

Newsletters

• This Week In Bevy - Animation Events, Curves, and no_std

Project/Tooling Updates

• On Rust in enterprise kernels
• FFI type mismatches in Rust for Linux
• Zapping pointers out of thin air
• Using LKMM atomics in Rust
• "pigg" (the Raspberry Pi GPIO GUI) 0.4.0 released

Observations/Thoughts

• Why Pin is a part of trait signatures (and why that's a problem)
• The Overwrite trait and Pin
• Improve an algorithm performance step by step
• Replacing nginx with axum
• An experiment in async Rust
• Designing A Fast Concurrent Hash Table
• Rethinking Builders… with Lazy Generics
• IPC in Rust
• Serde Trait - Part 3: Deserialization
• Memory for Nothing: Why Vec<usize> is (probably) a bad idea
• Upgrade the Logging in your Rust Tests
• Nine Rules for Running Rust on Embedded Systems
• Why Rust is taking the data engineering world by storm

Rust Walkthroughs

• Reading a Remote File Using Rust
• [video] Build with Naz : Rust memory address and size

Crate of the Week

This week's crate is bacon, a terminal application to run your cargo tasks on change in background.

Thanks to Denys Séguret for the self-suggestion! 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.

No Calls for participation were submitted this week.

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

468 pull requests were merged in the last week

• reserve guarded string literals (RFC #3593)
• ABI: pass aggregates by value on AIX
• codegen_ssa: consolidate tied target checks
• rustc_target: Add sme-b16b16 as an explicit aarch64 target feature
• add &pin (mut|const) T type position sugar
• add suggestion for removing invalid path sep :: in fn def
• also use outermost const-anon for impl items in non_local_defs lint
• check ABI target compatibility for function pointers
• don't assume traits used as type are trait objs in 2021 edition
• dont ICE when encountering post-mono layout cycle error
• emit an error for unstable attributes that reference already stable features
• fix clobber_abi and disallow SVE-related registers in Arm64EC inline assembly
• improve error messages for C-cmse-nonsecure-entry functions
• introduce SolverRelating type relation to the new solver
• make unused_parens's suggestion considering expr's attributes
• move dummy commit logic into x86_64-gnu-llvm-18
• move polarity into PolyTraitRef rather than storing it on the side
• precise capturing in traits
• shallowly match opaque key in storage
• support clobber_abi in MSP430 inline assembly
• suppress import errors for traits that couldve applied for method lookup error
• use throw intrinsic from stdarch in wasm libunwind
• miri: do not store synchronization primitive IDs in adressable memory
• miri: ensure that a macOS os_unfair_lock that is moved while being held is not implicitly unlocked
• miri: epoll event adding: no need to join, there's no old clock here
• miri: fix behavior of release_clock()
• miri: fix over synchronization of epoll
• miri: fixed pthread_getname_np impl for glibc
• miri: fixed get/set thread name implementations for macOS and FreeBSD
• miri: use new check_min_arg_count helper in more places
• impossible obligations fast path
• remove unnecessary sorts in rustc_hir_analysis
• stabilise const_char_encode_utf8
• stabilise const_make_ascii
• stabilize Pin::as_deref_mut()
• stabilize ci_rustc_if_unchanged_logic test
• stabilize const_option
• stabilize const_result
• stabilize debug_more_non_exhaustive
• stabilize duration_consts_float
• stabilize const ptr::write* and mem::replace
• stabilize const {slice,array}::from_mut
• optimize escape_ascii using a lookup table
• migrate lib's &Option<T> into Option<&T>
• intrinsics fmuladdf{32,64}: expose llvm.fmuladd.* semantics
• add #[track_caller] to allocating methods of Vec & VecDeque
• core/net: add Ipv[46]Addr::from_octets, Ipv6Addr::from_segments
• decouple WASIp2 sockets from WasiFd
• fix bug where option_env! would return None when env var is present but not valid Unicode
• implemented FromStr for CString and TryFrom<CString> for String
• library: const-stabilize MaybeUninit::assume_init_mut
• std: fix stdout-before-main
• hashbrown: ci: test the MSRV with minimal dependency versions
• hashbrown: revert "feat: borsh serde"
• cargo: complete: Don't complete files for any value
• cargo: git: dont fetch tags by default
• cargo: resolver: share conflict cache between activation retries
• cargo: add more SAT resolver tests
• cargo: docs: tools should only interpret a line starting with { as JSON
• cargo: feat: add custom completer for completing registry name
• cargo: fix panic when running cargo tree on a package with a cross compiled bindep
• cargo: fix: avoid inserting duplicate dylib_path_envvar when calling cargo run recursively
• cargo: improve resolver speed
• cargo: initial version of checksum based freshness
• cargo: remove the support for Cargo.toml of the cargo-script
• cargo: support package selection options like --exclude in cargo publish
• rustdoc-json: change item ID's repr from a string to an int
• rustdoc: add space between struct fields and their descriptions
• rustfmt: hint which style_edition to use instead of version
• clippy: implicit_saturating_sub: fix suggestion with a less volatile approach
• clippy: module_name_repetitions: don't warn if the item is in a private module
• clippy: add manual_ignore_cast_cmp lint
• clippy: check MethodCall/Call arg count earlier or at all
• clippy: check for needless raw strings in format_args!() template as well
• clippy: don't warn on proc macro generated code in needless_return
• clippy: fix large_stack_arrays triggering when nesting const items
• clippy: fix lint manual_slice_size_calculation when a slice is ref more than once
• clippy: fix span issue on implicit_saturating_sub
• clippy: mark unnecessary_first_then_check and byte_char_slices as Applicable
• clippy: move clippy::module_name_repetitions to restriction (from pedantic)
• clippy: move too_long_first_doc_paragraph to nursery
• clippy: only emit manual_c_str_literals in ≥ Edition 2021
• clippy: use correct std/core prefix in lint output
• rust-analyzer: add support for LLDB-DAP
• rust-analyzer: correctly parse use in generic parameters
• rust-analyzer: do not consider match/let/ref of place that evaluates to ! to diverge, disallow coercions from them too
• rust-analyzer: handle self-param outside of methods when renaming
• rust-analyzer: highlight exit points of async blocks
• rust-analyzer: respect references.exclude_tests in call-hierarchy
• rust-analyzer: fix panic when json project has relative buildfile paths
• rust-analyzer: comment out cast checks for unknown ptr kind
• rust-analyzer: do not consider mutable usage of deref to *mut T as deref_mut
• rust-analyzer: fix prettify_macro_expansion() when the node isn't the whole file
• rust-analyzer: include description in label details when detail field is marked for …
• rust-analyzer: incorrect autofix for missing wrapped unit in return expr
• rust-analyzer: join rustfmt overrideCommand with project root
• rust-analyzer: hir-ty: change struct + enum variant constructor formatting
• rust-analyzer: lsp: fix completion_item something_to_resolve not being a latch to true
• rust-analyzer: run subprocesses async in vscode extension
• rust-analyzer: skip #[test_case] expansion

Rust Compiler Performance Triage

No major changes this week.

Triage done by @simulacrum. Revision range: e6c46db4..5ceb623a

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:

• No RFCs were approved this week.

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

• No RFCs entered Final Comment Period this week.

Tracking Issues & PRs

Rust

• [disposition: merge] stabilize Strict Provenance and Exposed Provenance APIs
• [disposition: merge] make unsupported_calling_conventions a hard error
• [disposition: merge] Decide on name for derive(SmartPtr)
• [disposition: merge] Stabilize shorter_tail_lifetime
• [disposition: merge] Finish stabilization of result_ffi_guarantees
• [disposition: merge] Implement edition 2024 match ergonomics restrictions

Cargo

Language Team

• No Cargo 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

• [new] RFC: No (opsem) Magic Boxes
• [new] #[inline(required)]
• [new] RFC: introduce the flavor syntactic design pattern

Upcoming Events

Rusty Events between 2024-10-16 - 2024-11-13 🦀

Virtual

• 2024-10-16 | Virtual and In-Person (Vancouver, BC, CA) | Vancouver Rust
  • Rust Study/Hack/Hang-out
• 2024-10-17 | Virtual | Women in Rust
  • Part 3 of 4 - Hackathon Ideation Lab
• 2024-10-17| Virtual (Charlottesville, NC, US) | Charlottesville Rust Meetup
  • Crafting Interpreters in Rust Collaboratively
• 2024-10-17 | Mountain View, CA, US | Mountain View Rust Meetup
  • Rust Meetup at Hacker Dojo
• 2024-10-22 | Virtual (Dallas, TX, US) | Dallas Rust
  • Last Tuesday
• 2024-10-24 | Virtual | Women in Rust
  • Part 4 of 4 - Hackathon Showcase: Final Projects and Presentations
• 2024-10-24 | Virtual (Berlin, DE) | OpenTechSchool Berlin + Rust Berlin
  • Rust Hack and Learn | Mirror: Rust Hack n Learn Meetup
• 2024-10-26 | Virtual (Gdansk, PL) | Stacja IT Trójmiasto
  • Rust – budowanie narzędzi działających w linii komend
• 2024-10-29 | Virtual (Dallas, TX, US) | Dallas Rust
  • Last Tuesday
• 2024-10-31| Virtual (Charlottesville, NC, US) | Charlottesville Rust Meetup
  • Crafting Interpreters in Rust Collaboratively
• 2022-10-31 | Virtual (Nürnberg, DE) | Rust Nurnberg DE
  • Rust Nürnberg online
• 2024-11-07 | Virtual (Berlin, DE) | OpenTechSchool Berlin + Rust Berlin
  • Rust Hack and Learn | Mirror: Rust Hack n Learn Meetup
• 2024-11-12 | Virtual (Dallas, TX, US) | Dallas Rust
  • Second Tuesday

Africa

• 2024-11-02 | Kampala, UG | Rust Circle Kampala
  • Rust Circle Meetup

Asia

• 2024-10-17 - 2024-10-18 | Beijing, CN | Global Open-Source Innovation Meetup (GOSIM)
  • GOSIM 2024
• 2024-10-19 | Bangalore/Bengaluru, IN | Rust Bangalore
  • October 2024 Rustacean meetup

Europe

• 2024-10-16 | Manchester, UK | Rust Manchester
  • Rust Manchester Talks October - Leptos and Crux
• 2024-10-17 | Barcelona, ES | BcnRust
  • 16th BcnRust Meetup
• 2024-10-17 | Bern, CH | Rust Bern
  • 2024 Rust Talks Bern #3
• 2024-10-17 | Gdańsk, PL | Rust Gdansk
  • Rust Gdansk Meetup #4
• 2024-10-22 | London, UK | Rust London User Group
  • Rust London x London Python: SOLD OUT
• 2024-10-22 | Warsaw, PL | Rust Warsaw
  • New Rust Warsaw Meetup #2
• 2024-10-26 | Stockholm, SE | Stockholm Rust
  • Ferris' Fika Forum #6
• 2024-10-28 | Paris, FR | Rust Paris
  • Rust Meetup #71
• 2024-10-29 | Aarhus, DK | Rust Aarhus
  • Hack Night
• 2024-10-30 | Hamburg, DE | Rust Meetup Hamburg
  • Rust Hack & Learn October 2024
• 2024-10-31 | Berlin, DE | OpenTechSchool Berlin + Rust Berlin
  • Rust and Tell - Title
• 2024-11-06 | Oxford, UK | Oxford Rust Meetup Group
  • Oxford Rust and C++ social
• 2024-11-06 | Paris, FR | Paris Rustaceans
  • Rust Meetup in Paris

North America

• 2024-10-16 | Virtual and In-Person (Vancouver, BC, CA) | Vancouver Rust
  • Rust Study/Hack/Hang-out
• 2024-10-17 | Chicago, IL, US | Deep Dish Rust
  • Rust Hack Night/Happy Hour
• 2024-10-17 | Virtual and In-Person (Seattle, WA, US) | Seattle Rust User Group
  • October Meetup
• 2024-10-19 | Cambridge, MA, US | Boston Rust Meetup
  • North End Rust Lunch, Oct 19
• 2024-10-23 | Austin, TX, US | Rust ATX
  • Rust Lunch - Fareground
• 2024-10-27 | Cambridge, MA, US | Boston Rust Meetup
  • Kendall Rust Lunch, Oct 27
• 2024-10-28 | Boulder, CO, US | Boulder Rust Meetup
  • Generics from the Ground Up
• 2024-10-28 | Ferndale, MI, US | Detroit Rust
  • Rust Community Meetup - Ferndale
• 2024-10-28 | Minneapolis, MN US | Minneapolis Rust Meetup
  • Minneapolis Rust Meetup Happy Hour
• 2024-10-29 | Nashville, TN, US | Music City Rust Developers
  • Music City Rust Developers : State of the Group and Expectations for 2025
• 2024-11-04 | Brookline, MA, US | Boston Rust Meetup
  • Coolidge Corner Brookline Rust Lunch, Nov 4
• 2024-11-06 | Virtual (Indianapolis, IN, US) | Indy Rust
  • Indy.rs - with Social Distancing
• 2024-11-07 | St. Louis, MO, US | STL Rust
  • Game development with Rust and the Bevy engine
• 2024-11-12 | Ann Arbor, MI, US | Detroit Rust
  • Rust Community Meetup - Ann Arbor

Oceania

• 2024-10-28 | Melbourne, VIC, AU | Rust Melbourne
  • October 2024 Rust Melbourne Meetup
• 2024-10-29 | Canberra, ACT, AU | Canberra Rust User Group (CRUG)
  • June Meetup
• 2024-10-31 | Auckland, NZ | Rust AKL
  • Rust AKL: Rust on AWS: Sustainability + Peace: Zero Stress Automation

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

We'd have buttons on the screen to control the fans of the car. I had to write a lot of code before I could compile it all, a big jenga tower. But once it compiled, the fans started to work! Very impressed.

– Julius Gustavsson on the Tweedegolf blog

Thanks to scottmcm 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