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

Newsletters

• This Month in Rust OSDev: October 2023

Project/Tooling Updates

• rust-libp2p v0.53 has been released
• Zellij 0.39.0 released
• Officially Qualfied - Ferrocene
• Rocket's 4th v0.5 Release Candidate

Observations/Thoughts

• Writing Rust Bindings for My Python App
• A four year plan for async Rust
• Cursed Rust: Printing Things The Wrong Way
• Rust for JavaScript Developers: An Overview of Testing
• Why Golang instead of Rust to develop the Krater desktop app
• Google Rewriting Android's Binder In Rust With Promising Results
• Dump Rust Struct or Enum Memory Representation as Bytes
• How Open Source Projects are Using Kani to Write Better Software in Rust
• Creating High Performance Asynchronous Backends With Burn-Compute
• Goodbye Python, Hello Rust: Building a RAG CLI Application with Orca
• Variadic generics, again
• Using Rust, Chrome and NixOS to Take Headless Screenshots for Social Sharing
• sudo-rs' first security audit
• Destructing trees safely and cheaply
• Edge IoT with Rust on ESP: NTP

Rust Walkthroughs

• Using Modern Linux Sockets

Miscellaneous

• Migrating SecureDrop’s PGP backend from GnuPG to Sequoia
• [video] 10x faster - taking charge of the compiler backend
• [video] RISC-V Vector Extension in Rust
• Embedding simple CSV file in Rust application

Crate of the Week

This week's crate is floem, a native Rust UI library with fine-grained reactivity.

Despite receiving no suggestions, llogiq is reasonably pleased with his choice.

Please submit your suggestions and votes for next week!

Call for Participation

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 - Make ockam identity delete (no args) interactive by asking the user to choose from a list of identity names to delete (tuify)
• Ockam - Make ockam tcp-outlet delete (no args) interactive by asking the user to choose from a list of tcp-outlet aliases to delete (tuify)
• Ockam - Make ockam project show (no args) interactive by asking the user to choose from a list of projects to show (tuify)

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

Updates from the Rust Project

366 pull requests were merged in the last week

• dropck_outlives check whether generator witness needs_drop
• account for ref and mut in the wrong place for pattern ident renaming
• add a stable MIR visitor
• add all RPITITs when augmenting param-env with GAT bounds in check_type_bounds
• add diagnostic items for a few of core's builtin macros
• add support for pre-unix-epoch file dates on Apple platforms
• add the Span of the move keyword to the HIR
• also consider TAIT to be uncomputable if the MIR body is tainted
• avoid the path trimming ICE lint in error reporting
• avoid unnecessary comparison in partition_equal
• check binders with bound vars for global bounds that don't hold
• consts: remove dead code around i1 constant values
• coverage: replace impossible coverage::Error with assertions
• derive TyEncodable/TyDecodable in rustc_type_ir
• detect misparsed binop caused by missing semi
• detect object safety errors when assoc type is missing
• do not ICE on constant evaluation failure in GVN
• do not assert in op_to_const
• don't check for alias bounds in liveness when aliases have escaping bound vars
• don't emit delayed good-path bugs on panic
• don't pass -stdlib=libc++ when building C files on macOS
• enable cross-crate-inlining when MIR inlining is enabled
• enable parallel rustc front end in nightly builds
• fallback for construct_generic_bound_failure
• fix excessive initialization and reads beyond EOF in io::copy(_, Vec<u8>) specialization
• fix incorrect trait bound restriction suggestion
• fix order of implementations in the "implementations on foreign types" section
• guarantee representation of None in NPO
• guarantee that char has the same size and alignment as u32
• hint optimizer about try-reserved capacity
• inline and remove create_session
• make sure that predicates with unmentioned bound vars are still considered global in the old solver
• make the randomize feature of rustc_abi additive
• match usize/isize exhaustively with half-open ranges
• prepopulate opaque ty storage before using it
• pretty print Fn traits in rustc_on_unimplemented
• recover from missing param list in function definitions
• refactor: move suggestion functions from demand to suggestions
• remove obsolete support for linking unwinder on Android
• remove support for alias -Z symbol-mangling-version
• remove support for compiler plugins
• replace switch to unreachable by assume statements
• set max_atomic_width for riscv32*-esp-espidf to 32
• turn const_caller_location from a query to a hook
• use FxIndexSet in the symbol interner
• use derivative for Clone/PartialOrd/Ord/Hash in rustc_type_ir
• use global cache when computing proof trees
• use the correct span when emitting the env! result
• warn users who set non_exhaustive_omitted_patterns lint level on a match arm
• when encountering unclosed delimiters during lexing, check for diff markers
• enable src/math for all UEFI targets
• intrinsics macro: fix non-weak aeabi generation
• this enables math module for riscv32 targets
• stabilize const_maybe_uninit_zeroed and const_mem_zeroed
• stabilize file_set_times
• fix switch_stdout_to on Windows7
• add track_caller to transmute_copy
• delegate <Box<E> as Error>::provide to <E as Error>::provide
• support enum variants in offset_of!
• feature gate enums in offset_of
• override Waker::clone_from to avoid cloning Wakers unnecessarily
• codegen_gcc: fix vector compilation error
• cargo: feat(trim-paths): set env CARGO_TRIM_PATHS for build scripts
• cargo toml: Pull out the schema
• cargo: fix an unhelpful panic message
• cargo: implement -Ztrim-paths (RFC #3127)
• cargo: merge trim-paths from different profiles
• rustdoc: accept less invalid Rust
• rustfmt: fixes comma added to comment in where-clause
• clippy: unused_enumerate_index: don't ICE on empty tuples
• clippy: add unused_enumerate_index lint
• clippy: fix dbg_macro semi span calculation
• clippy: fix enum_variant_names depending lint depending on order
• clippy: fix get_first false negative for VecDeque
• clippy: new lint: unnecessary_fallible_conversions
• rust-analyzer: add generate_mut_trait_impl assist
• rust-analyzer: import trait with alias
• rust-analyzer: skip checking token tree count for include! macro call
• rust-analyzer: fix docs path for derive macros
• rust-analyzer: vSCode metadata. category:formatters

Rust Compiler Performance Triage

A difficult week for triage, due to what appears to be system-level disruption to measurement apparatus, yielding transient noise (and potentially masking actual problems). The main non-noise performance change was huge regression to bitmaps introduced by PR 117131, and that already has a fix in-flight fix (PR #117542). The other thing worth noting is that the parallel rustc front-end has been enabled in the nighlty builds, which has introduced some overhead that was expected by wg-parallel-rustc.

Triage done by @pnkfelix. Revision range: 650991d6..7b97a5ca

10 Regressions, 4 Improvements, 3 Mixed; 3 of them in rollups 68 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:

• Add "crates.io Policy Update" RFC
• Merge RFC 3498: "Lifetime Capture Rules 2024"

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

• [disposition: merge] Add T: ?Sized to RwLockReadGuard and RwLockWriteGuard's Debug impls.
• [disposition: merge] Tracking Issue for file_create_new
• [disposition: merge] feat: implement DoubleEndedSearcher for CharArray[Ref]Searcher
• [disposition: merge] TAIT defining scope options
• [disposition: merge] Add std::hash::{DefaultHasher, RandomState} exports (needs FCP)

Language Reference

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

Unsafe Code Guidelines

• Decide on zero-sized offsets and memory accesses

New and Updated RFCs

• Arbitrary self types v2.

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:

• No RFCs issued a call for testing 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.

Upcoming Events

Rusty Events between 2023-11-08 - 2023-12-06 🦀

Virtual

• 2023-11-08 | Virtual(Boulder, CO, US) | Solid State Depot - The Boulder Makerspace
  • Placeholder: Boulder Rust Meetup
• 2023-11-09 | Virtual (Linz, AT) | Rust Linz
  • Rust Meetup Linz - 34rd Edition
• 2023-11-09 | Virtual (Nuremberg, DE) | Rust Nuremberg
  • Rust Nürnberg online
• 2023-11-10 | Virtual (Bangalore, IN) | Learn Everything About Programming
  • Getting started with rust-lang
• 2023-11-12 | Virtual (Tel Aviv-Yafo, IL) | Code Mavens
  • Rust in Israel - Rust Digger
• 2023-11-14 | Virtual (Dallas, TX, US) | Dallas Rust
  • Second Tuesday
• 2023-11-14 | Virtual (Kyiv, UA) | Yalantis Education
  • Довгий шлях до першого комерційного досвіду або до чого тут Rust?
• 2023-11-15 | Virtual (Cardiff, UK)| Rust and C++ Cardiff
  • Building Our Own Locks (Atomics & Locks Chapter 9)
• 2023-11-15 | Virtual (Richmond, VA, US) | Linux Plumbers Conference
  • Rust Microconference in LPC 2023 (Nov 13-16)
• 2023-11-15 | Virtual (Vancouver, BC, CA) | Vancouver Rust
  • Nightly Night: impl Trait in Type Aliases
• 2023-11-16 | Virtual (Charlottesville, NC, US) | Charlottesville Rust Meetup
  • Crafting Interpreters in Rust Collaboratively
• 2023-11-16 | Virtual (Vilnius, LT) | Vilnius Rust and Go Meetup Group
  • Enjoy our first Rust event
• 2023-11-21 | Virtual (Berlin, DE) | OpenTechSchool Berlin
  • Rust Hack and Learn
• 2023-11-21 | Virtual (Washington, DC, US) | Rust DC
  • Mid-month Rustful
• 2023-11-23 | Virtual (Edmonton, AB, CA) | Edmonton R User Group - Yegrug
  • Edmonton R User Group Meetup: R and Rust, like a match made in heaven
• 2023-11-28 | Virtual (Dallas, TX, US) | Dallas Rust
  • Last Tuesday
• 2023-11-29 | Virtual (Cardiff, UK)| Rust and C++ Cardiff
  • Atomics & Locks Book Club Final Chapter! (Chapter 10)
• 2023-11-30 | Virtual (Charlottesville, NC, US) | Charlottesville Rust Meetup
  • Crafting Interpreters in Rust Collaboratively
• 2023-11-30 | Virtual (Dublin, IE) | Rust Dublin
  • Automating expertise with cargo-semver-checks
• 2023-12-01 | Virtual (Cardiff, UK)| Rust and C++ Cardiff
  • Rust & C++ Christmas Game Jam Kick-Off!
• 2023-12-02 | Virtual (Kampala, UG) | Rust Circle Kampala
  • Rust Circle Meetup
• 2023-12-05 | Virtual (Berlin, DE) | OpenTechSchool Berlin
  • Rust Hack and Learn | Mirror
• 2023-12-05 | Virtual (Buffalo, NY, US) | Buffalo Rust Meetup
  • Buffalo Rust User Group, First Tuesdays

Europe

• 2023-11-09 | Barcelona, ES | BcnRust
  • 11th BcnRust Meetup
• 2023-11-09 | Paris, FR | Paris Rustaceans
  • Rust Meetup in Paris
• 2023-11-09 | Reading, UK | Reading Rust Workshop
  • Reading Rust Meetup at Browns
• 2023-11-21 | Augsburg, DE | Rust - Modern Systems Programming in Leipzig
  • GPU processing in Rust
• 2023-11-23 | Biel/Bienne, CH | Rust Bern
  • Rust Talks Bern @ Biel: Embedded Edition

North America

• 2023-11-08 | Boulder, CO, US | Boulder Rust Meetup
  • Let's make a Discord bot!
• 2023-11-14 | New York, NY, US | Rust NYC
  • Rust NYC Monthly Mixer: Share, Show, & Tell! 🦀
• 2023-11-14 | Seattle, WA, US | Cap Hill Rust Coding/Hacking/Learning
  • Rusty Coding/Hacking/Learning Night
• 2023-11-15 | Richmond, VA, US + Virtual | Linux Plumbers Conference
  • Rust Microconference in LPC 2023 (Nov 13-16)
• 2023-11-16 | Mountain View, CA, US | Mountain View Rust Meetup
  • Rust Meetup at Hacker Dojo
• 2023-11-16 | Nashville, TN, US | Music City Rust Developers
  • Python loves Rust!
• 2023-11-16 | Seattle, WA, US | Seattle Rust User Group
  • Seattle Rust User Group Meetup
• 2023-11-21 | San Francisco, CA, US | San Francisco Rust Study Group
  • Rust Hacking in Person
• 2023-11-22 | Austin, TX, US | Rust ATX
  • Rust Lunch - Fareground
• 2023-11-28 | Pasadena, CA, US | Pasadena Thursday Go / Rust
  • Monthly Rust group

Oceania

• 2023-11-21 | Christchurch, NZ | Christchurch Rust Meetup Group
  • Christchurch Rust meetup meeting
• 2023-11-28 | Canberra, ACT, AU | Rust Canberra
  • November 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

For Binder to continue to meet Android's needs, we need better ways to manage (and reduce!) complexity without increasing the risk.

The biggest change is obviously the choice of programming language. We decided to use Rust because it directly addresses a number of the challenges within Binder that we have faced during the last years.

– Alice Ryhl on the Linux Kernel Mailing List

Thanks to Vincent de Phily 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