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

Newsletters

• thisweekinbevy - 0.14.1, tracking change detection, and more rendering examples

Project/Tooling Updates

• Tauri 2.0 Release Candidate
• CGlue 0.3 Future and Beyond
• ratatui - v0.28.0
• Pigg 0.3.3 the GUI for RPi GPIO interaction released, with Remote GPIO feature!
• Announcing SeaORM 1.0
• Danube - Queuing and Pub/Sub message patterns

Observations/Thoughts

• Trying and mostly failing to optimize frustum culling in a WebGL + TS + Rust engine
• Panic! At The Async Runtime Shutdown
• Debugging a rustc segfault on illumos
• Tracing my way with tracing-rs
• [Series] The Hitchhiker’s Guide to Building a Distributed Filesystem in Rust.
• Best Rust books for 2024
• Phantom Menace: memory leak that wasn't there
• Developing a cryptographically secure bootloader for RISC-V in Rust
• Extending the #[diagnostic] tool attribute namespace

Rust Walkthroughs

• Tracing Tokio Resources
• [Series] Mastering Dependency Injection in Rust: Crafting a Custom Container

Research

• The Hitchhiker’s Guide to Building a Distributed Filesystem in Rust.

Miscellaneous

• Rustic: Enhanced Org Babel integration
• Efficient Logging - Speeding up production code by logging more efficiently

Crate of the Week

This week's crate is WhenFS, a FUSE filesystem that misuses your google calendar as storage. And yes, your schedule will look as packed as mine once you store one or two files in there.

Despite yet another week fully devoid of suggestions nor votes, llogiq is reasonably pleased with his choice.

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.

• rencfs - Abstract file access layer
• rencfs - Add RustCrypto as a feature
• rencfs - File and fs API
• rencfs - io API
• rfs - Coordinator node API)
• rfs - Data node API
• rfs - File upload and changes
• rfs - Communication between Coordinator and Data nodes
• syncoxiders - Two-way sync
• syncoxiders - Sync chunks in parallel
• syncoxiders - Integrate SurrealDB to store metadata
• syncoxiders - Migrate scripts tests to integration tests
• rencfs-desktop - Implement daemon
• Proposal: Deprecate Tokio's LocalSet

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

381 pull requests were merged in the last week

• fix vita build of std and forbid unsafe in unsafe in the os/vita module
• derive(SmartPointer): require pointee to be maybe sized
• add #[must_use] to some into_raw* functions
• add REDUNDANT_IMPORTS lint for new redundant import detection
• add f16 and f128 math functions
• allow overwriting the output of rustc --version
• allow setting link-shared and static-libstdcpp with CI LLVM
• android: remove libstd hacks for unsupported Android APIs
• assert that all attributes are actually checked via CheckAttrVisitor and aren't accidentally usable on completely unrelated HIR nodes
• better handle suggestions for the already present code and fix some suggestions
• built-in derive: remove BYTE_SLICE_IN_PACKED_STRUCT_WITH_DERIVE hack and lint
• cleanup sys module to match house style
• create COFF archives for non-LLVM backends
• custom MIR: add support for tail calls
• delegation: second attempt to improve perf
• delegation: support generics for delegation from free functions
• detect non-lifetime binder params shadowing item params
• do not fire unhandled attribute assertion on multi-segment AttributeType::Normal attributes with builtin attribute as first segment
• don't re-elaborate already elaborated caller bounds in method probe
• elaborate unknowable goals
• emit an error if #[optimize] is applied to an incompatible item
• enforce supertrait outlives obligations hold when confirming impl
• fix removed box_syntax diagnostic if source isn't available
• fix the invalid argument type
• ignore use declaration reformatting in .git-blame-ignore-revs
• implement UncheckedIterator directly for RepeatN
• improve error message when global_asm! uses asm! operands
• interpret: on a signed deref check, mention the right pointer in the error
• make /// doc comments compatible with naked functions
• mark Parser::eat/check methods as #[must_use]
• match LLVM ABI in extern "C" functions for f128 on Windows
• match lowering: Hide Candidate from outside the lowering algorithm
• more unsafe attr verification
• normalize when equating dyn tails in MIR borrowck
• on short error format, append primary span label to message
• peel off explicit (or implicit) deref before suggesting clone on move error in borrowck, remove some hacks
• properly mark loop as diverging if it has no breaks
• remove crate_level_only from ELIDED_LIFETIMES_IN_PATHS
• revert recent changes to dead code analysis
• set branch protection function attributes
• simplify match based on the cast result of IntToInt
• structured suggestion for extern crate foo when foo isn't resolved in import
• temporarily switch ambiguous_negative_literals lint to allow
• the output in stderr expects panic-unwind
• turn invalid_type_param_default into a FutureReleaseErrorReportInDeps
• tweak type inference for const operands in inline asm
• use object in run-make/symbols-visibility
• use a separate pattern type for rustc_pattern_analysis diagnostics
• miri: add a flag to do recursive validity checking
• miri: add miri_start support
• miri: use Scalar consistently in foreign item emulation
• linker: pass fewer search directories to the linker
• use Vec in instantiate_binder_with_fresh_vars
• change output normalization logic to be linear against size of output
• check divergence value first before doing span operations in warn_if_unreachable
• accelerate GVN a little
• stabilize Wasm relaxed SIMD
• stabilize unsafe extern blocks (RFC 3484)
• enable std::io::copy specialisation for std::pipe::{PipeReader, PipeWriter}
• rewrite binary search implementation
• implement cursors for BTreeSet
• implement the once_wait feature
• configure which platforms have f16 and f128 enabled by default
• hashbrown: implement Default for iterators
• regex: rust nightly removed the lifetime from Pattern
• cargo-miri: better error when we seem to run inside bootstrap but something is wrong
• cargo: build-std: remove hack on creating virtual std workspace
• cargo: config: Adjust MSRV resolve config field name / values
• cargo: publish: Don't strip non-dev features
• cargo: also build manpage for cargo.md
• rustdoc-json: discard non-local inherent impls for primitives
• rustdoc: cleanup CacheBuilder code for building search index
• rustdoc: fix handling of Self type in search index and refactor its representation
• rustdoc: make the hover trail for doc anchors a bit bigger
• rustdoc: Make the buttons remain when code example is clicked
• rustdoc: simplify body usage
• rustfmt: add repo cloning to check-diff crate
• rustfmt: check exit status of git commands spawned by build script
• rustfmt: impl rewrite_result for Pat, TuplePatField
• clippy: check exit status of subcommands spawned by rustc_tools_util
• clippy: fix redundant_closure false positive with closures has return type contains 'static
• clippy: fix redundant_slicing when the slice is behind a mutable reference
• clippy: fix broken list for lints config
• clippy: fix false positive for missing_backticks in footnote references
• clippy: limit number of nonminimal_bool ops
• clippy: lintcheck: force warn all lints
• clippy: make restriction lints use span_lint_and_then (a → e)
• clippy: make restriction lints use span_lint_and_then (q → w)
• clippy: remove multispan_sugg[_with_applicability]
• clippy: remove duplicated peel_middle_ty_refs
• clippy: simplify lint deprecation
• clippy: use a deterministic number of digits in rustc_tools_util commit hashes
• clippy: use a single multipart suggestion for implicit_hasher
• rust-analyzer: implement diagnostic for await outside of async
• rust-analyzer: load sysroot library via cargo metadata
• rust-analyzer: support inlay hint for more expr with label
• rust-analyzer: apply IndexMut obligations for non-assigning mutable index usages
• rust-analyzer: errors on method call inferences with elided lifetimes
• rust-analyzer: insert a generic arg for impl Trait when lowering generic args
• rust-analyzer: insert a tail Ok(()) for expr block instead of wrapping with Ok
• rust-analyzer: panic in path transform with default type parameters
• rust-analyzer: remove AbsPath requirement from linkedProjects
• rust-analyzer: surpress type mismatches in calls with mismatched arg counts
• rust-analyzer: improve crate manifests, adding missing [package.repository] and [package.description] fields
• rust-analyzer: segregate syntax and semantic diagnostics
• rust-analyzer: split out syntax-bridge into a separate crate
• rust-analyzer: when josh-proxy screws up the roundtrip, say what the involved commits are

Rust Compiler Performance Triage

This week saw several large improvements caused mostly by the update to LLVM 19. There were some regressions in several pull requests, but most of them were immediately fixed in a follow-up PR.

Triage done by @kobzol. Revision range: 7e3a9718..8c7e0e16

Summary:

6 Regressions, 3 Improvements, 5 Mixed; 4 of them in rollups 51 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:

• Merge RFC 3529: Add named path bases to cargo
• Merge RFC 3668: Async closures
• Promote aarch64-apple-darwin to Tier 1
• RFC for project goals

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 raw_ref_op (RFC 2582)
• [disposition: merge] Tracking Issue for Ready::into_inner()
• [disposition: merge] Tracking issue for thread::Builder::spawn_unchecked
• [disposition: merge] Tracking Issue for is_none_or
• [disposition: merge] CloneToUninit impls
• [disposition: close] Tracking issue for HashMap OccupiedEntry::{replace_key, replace_entry}
• [disposition: close] Tracking issue for HashMap::raw_entry
• [disposition: merge] Implement DoubleEnded and ExactSize for Take\<Repeat> and Take\<RepeatWith>
• [disposition: merge] Implement owned ops for HashSet and BTreeSet
• [disposition: merge] Tracking Issue for Option::get_or_insert_default
• [disposition: merge] Unify run button display with "copy code" button and with mdbook buttons
• [disposition: merge] Greatly speed up doctests by compiling compatible doctests in one file

Cargo

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

Language Team

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

Language Reference

• [disposition: \<not specified>] Reformat (and only reformat) the inline assembly chapter

Unsafe Code Guidelines

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

New and Updated RFCs

• [new] crates.io: Remove dev-dependencies from the index

Upcoming Events

Rusty Events between 2024-08-07 - 2024-09-04 🦀

Virtual

• 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: Typestate Pattern in Rust
• 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 | Conf42: Online Tech Events
  • Conf42 Rustlang 2024
• 2024-08-22 | Virtual (Charlottesville, NC, US) | Charlottesville Rust Meetup
  • Crafting Interpreters in Rust Collaboratively
• 2024-08-22 | Virtual (Karlsruhe, DE) | Karlsruhe Functional Programmers Group
  • Stammtisch (gemeinsam mit der C++ UG KA): various topics, from C++ to Rust
• 2024-08-27 | Virtual | Ardan Labs
  • Fearless Concurrency with Rust
• 2024-08-27 | Virtual (Bordeaux, FR) | Rust Bordeaux
  • Live coding - A distance #1
• 2024-08-27 | Virtual (Dallas, TX, US) | Dallas Rust
  • Last Tuesday
• 2024-08-27 | Virtual (Tel Aviv, IL) | Code Mavens
  • Declarative macros in Rust (Virtual) - מקרוים בראסט
• 2024-08-28 | Virtual (Tel Aviv, IL) | Code Mavens
  • Command Line Tools: Implementing wc in Rust (English, Virtual)
• 2024-08-29 | Virtual (Berlin, DE) | OpenTechSchool Berlin + Rust Berlin
  • Rust Hack and Learn | Mirror: Rust Hack n Learn Meetup
• 2024-09-03 | Virtual (Buffalo, NY, US) | Buffalo Rust Meetup
  • Buffalo Rust User Group
• 2024-09-04 | Virtual (Indianapolis, IN, US) | Indy Rust
  • Indy.rs - with Social Distancing

Europe

• 2024-08-14 | Köln/Cologne, DE | Rust Cologne
  • This Month in Rust, August
• 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)
• 2024-08-22 | Manchester, UK | Rust Manchester
  • Rust Manchester Talks August
• 2024-08-26 | Mainz, DE | Fachschaft Mathematik+Informatik der JGU Mainz
  • Ferienkurs Rust
• 2024-08-29 | Berlin, DE | OpenTechSchool Berlin + Rust Berlin
  • Rust and Tell - Title

North America

• 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
• 2024-08-29 | Nashville, TN, US | Music City Rust Developers
  • Music City Rust Developers : placeholder

Oceania

• 2024-08-22 | Auckland, NZ | Rust AKL
  • Rust AKL: Dot IX: Diagram Generator + Deep Learning from Scratch in Rust
• 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

Want to have a crate with a million features? Host your own registry and revel in the combinatorial explosion of choices!

– Jake Goulding on rust-users

Thanks to Jonas Fassbender 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