This Week In Rust 536#

2024-02-28

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#

Foundation#

Newsletters#

Project/Tooling Updates#

• This month in Servo: gamepad support, font fallback, Space Jam, and more!
• Announcing Jco 1.0
• This month in Pavex, #9
• argmin 0.10.0 - a Rust crate for numerical optimization

Observations/Thoughts#

• Text labels rendering on a map with Rust - research and design

• Rust developers fear language is getting too complex and prefer bug fixes to new features

• Lessons learnt from building a distributed system in Rust

• How Rust Could Change Robotics

• Asynchronous clean-up

• Edge IoT with Rust on ESP: Ping!

• ESP Embedded Rust: Command Line Interface

• ESP Embedded Rust: Ping CLI App Part 2

• Convert a String to int in Rust

• Mastering ManuallyDrop<T> - A Guide to Explicit Resource Management in Rust

• Rust, but async

Rust Walkthroughs#

• [HEB][video] Rust Course

• Matching and iterators in Rust

• Practical guide to Error Handling in Rust

• Building an Async Runtime with mio

Research#

Miscellaneous#

• Firmware for an ESP32 to read from a noise sensor in Rust

• Guide to using TensorFlow in Rust

• A Twist on Wadler's Printer

• Implementing API Rate Limiting in Rust

• How to benchmark Rust code with Iai

• [audio] Sentry - Rust in Production Podcast

• [video] A First Look at Lifetimes in Rust

• How Rust Could Change Robotics

• Sequential-storage: efficiently store data in flash

Crate of the Week#

This week's crate is web-audio-api-rs, a Rust implementation of the Web Audio API for use outside the browser.

Thanks to Otto Rottier 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:

• 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.

Call for Participation; projects and speakers#

Updates from the Rust Project#

430 pull requests were merged in the last week

• Avoid non-local definitions in functions (RFC #3373)

• wasm: store rlib metadata in wasm object files

• account for RPITIT in E0310 explicit lifetime constraint suggestion

• actually use the right closure kind when checking async Fn goals

• add #[rustc_no_mir_inline] for standard library UB checks

• allow for a missing adt_def in NamePrivacyVisitor

• avoid generalization inside of aliases

• by changing some attributes to only_local, reducing encoding attributes in the crate metadate

• do not const prop unions

• don't ICE on anonymous struct in enum variant

• expand weak alias types before collecting constrained/referenced late bound regions + refactorings

• fix panic when compiling Rocket

• make intrinsic fallback bodies cross-crate inlineable

• make it possible for outside crates to inspect a mir::ConstValue with the interpreter

• make non-PartialEq-typed consts as patterns a hard error

• mark min_exhaustive_patterns as complete

• match lowering: Introduce a TestCase enum to replace most matching on PatKind

• match lowering: eagerly simplify match pairs

• match lowering: simplify empty candidate selection

• match lowering: test one or pattern at a time

• Fix liveness analysis in the presence of never patterns

• no need to validate_alias_bound_self_from_param_env in assemble_alias_bound_candidates

• prevent cycle in implied predicates computation

• promotion: don't promote int::MIN / -1

• properly emit expected ; on #[attr] expr

• provide suggestions through rustc_confusables annotations

• refactor trait implementations in core::convert::num

• split Diagnostics for Uncommon Codepoints: Add Individual Identifier Types

• support async trait bounds in macros

• unify dylib loading between proc macros and codegen backends

• when encountering <&T as Clone>::clone(x) because T: Clone, suggest #[derive(Clone)]

• miri: /miri many-seeds: support MIRI_SEED_END to control the end of the seed range

• miri: add "cargo miri clean" command

• miri: windows miri-script execution ergonomics

• use br instead of a conditional when switching on a constant boolean

• stabilize cfg_target_abi

• improve UEFI stdio

• windows: use ProcessPrng for random keys

• require simd_insert, simd_extract indices to be constants

• make Barrier::new() const

• implement MappedMutexGuard, MappedRwLockReadGuard, and MappedRwLockWriteGuard

• add "algebraic" fast-math intrinsics, based on fast-math ops that cannot return poison

• remove useless 'static bounds on Box allocator

• mpsc: fix race between block initialization and receiver disconnection

• futures: add 'static bound to waker_ref

• cargo add: Improve error when adding registry packages while vendored

• cargo: Control clap colors through config

• cargo: Respect CARGO_TERM_COLOR in '--list' and '-Zhelp'

• cargo: error messages when collecting workspace members now mention the workspace root location

• cargo: support target.<triple>.rustdocflags officially

• rustdoc: include crate name in links for local primitives

• clippy: box_default: preserve required path segments

• clippy: read_line_without_trim: detect string literal comparison and .ends_with() calls

• clippy: add unnecessary_clippy_cfg lint

• clippy: add new multiple_bound_locations lint

• clippy: add new unnecessary_get_then_check lint

• clippy: allow unused_imports, and unused_import_braces on use

• clippy: don't lint infinite_loop in external or proc macros

• clippy: make redundant_guards take constness into account

• clippy: unused_unit: be careful with expressions with attributes

• clippy: new lint: empty docs

• clippy: extend unnecessary_to_owned to handle Borrow trait in map types

• clippy: fix sign-handling bugs and false negatives in cast_sign_loss

• clippy: fix suggestion error in useless_vec

• clippy: fix no_effect_underscore_binding firing on ignored parameters of async fns

• clippy: look for implied_bounds_in_impls in more positions

• clippy: take lifetime extension into account in ref_as_ptr

• rust-analyzer: add assist for filling fields by replacing ellipsis in record syntax

• rust-analyzer: add short flag -V for consistency with other rust tooling

• rust-analyzer: add "make tuple" tactic to term search

• rust-analyzer: replace_filter_map_next_with_find_map shouldn't work for dyn trait

• rust-analyzer: don't panic on synthetic syntax in inference diagnostics

• rust-analyzer: fix completions panicking with certain macro setups

• rust-analyzer: fix deadlock in recreate_crate_graph <-> file_line_index

• rust-analyzer: fix modules in blocks not resolving in ide layer

• rust-analyzer: fix proc-macro server not accounting for string delimiters correctly

• rust-analyzer: fix recompiles due to RUSTC_BOOTSTRAP

• rust-analyzer: panic when inlining callsites inside macros' parameters

• rust-analyzer: merge BorrowKind::Unique into BorrowKind::Mut

• rust-analyzer: speed up Method Completions By Taking Advantage of Orphan Rules

Rust Compiler Performance Triage#

A rare week where regressions out powered improvements to make the compiler roughly half a percent slower on average on nearly 100 benchmarks. Some regressions have fixes in the pipeline, but some remain elusive or were introduced to address correctness issues.

Triage done by @rylev. Revision range: 5af21304..71ffdf7f

Summary:

(instructions:u)	mean	range	count
Regressions ❌ (primary)	1.0%	[0.2%, 4.4%]	69
Regressions ❌ (secondary)	1.4%	[0.2%, 4.9%]	66
Improvements ✅ (primary)	-1.1%	[-3.3%, -0.2%]	28
Improvements ✅ (secondary)	-0.6%	[-1.5%, -0.2%]	33
All ❌✅ (primary)	0.4%	[-3.3%, 4.4%]	97

4 Regressions, 6 Improvements, 5 Mixed; 2 of them in rollups 58 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:

• 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.

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Tracking Issues & PRs#

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Rust#

• [disposition: merge] Lint singleton gaps after exclusive ranges
• [disposition: merge] Tracking Issue for slice::split_at_unchecked() and split_at_mut_unchecked()
• [disposition: merge] Tracking Issue for generic NonZero
• [disposition: merge] Made INVALID_DOC_ATTRIBUTES lint deny by default
• [disposition: merge] Tracking Issue for ARM CRC32 intrinsics
• [disposition: merge] use confstr(_CS_DARWIN_USER_TEMP_DIR, ...) as a TMPDIR fallback on Darwin

#

New and Updated RFCs#

• [new] RFC: RArrow Dereference for Pointer Ergonomics

Upcoming Events#

Rusty Events between 2024-02-28 - 2024-03-27 🦀

Virtual#

• 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 (Dublin, IE) | Rust Dublin
  • An intro to nom, parsing made easy for Rustaceans
• 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)
• 2024-03-14 | Virtual (Berlin, DE) | OpenTechSchool Berlin + Rust Berlin
  • Rust Hack and Learn | Mirror: Rust Hack n Learn Meetup | Mirror: Berline.rs page
• 2024-03-14 | Virtual (Nürnberg, DE) | Rust Nüremberg
  • Rust Nürnberg 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#

• 2024-02-29 | Berlin, DE | Rust Berlin
  • Rust and Tell - Season start 2024
• 2024-02-29 | Copenhagen, DK | Copenhagen Rust Community
  • Rust Meetup #44 sponsored by Bang & Olufsen
• 2024-03-06 | Zürich, CH | Rust Zürisee
  • How to (partial) Migration - March Meetup
• 2024-03-12 | Munich, DE + Virtual | Rust Munich
  • Rust Munich 2024 / 1 - hybrid
• 2024-03-13 | Paris, FR | Paris Rustaceans
  • Rust Meetup in Paris
• 2024-03-14 | Reading, UK | Reading Rust Workshop
  • Reading Rust Meetup at Browns
• 2024-03-19 | Aarhus, DK | Rust Aarhus
  • Hack Night
• 2024-03-19 | Leipzig, DE | Rust - Modern Systems Programming in Leipzig
  • Rust Interactive Session
• 2024-03-20 | Girona, ES | Rust Girona
  • Introduction to programming Microcontrollers with Rust
• 2024-03-21 | Augsburg, DE | Rust Meetup Augsburg
  • Augsburg Rust Meetup #6
• 2024-03-21 | Lille, FR | Rust Lille
  • Rust Lille #6: Du RSS et de L'ECS !
• 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#

• 2024-02-28 | Austin, TX, US | Rust ATX
  • Rust Lunch - Fareground
• 2024-02-28 | Chicago, IL, US | Deep Dish Rust
  • Rust Happy Hour
• 2024-03-04 | Cambridge, MA, US | Boston Rust Meetup
  • Central Cambridge Rust Lunch
• 2024-03-07 | Mountain View, CA, US | Mountain View Rust Meetup
  • Rust Meetup at Hacker Dojo
• 2024-03-13 | Boston, MA, US | Boston Rust Meetup
  • Northeastern Rust Lunch
• 2024-03-19 | San Francisco, CA, US | San Francisco Rust Study Group
  • Rust Hacking in Person
• 2024-03-27 | Austin, TX, US | Rust ATX
  • Rust Lunch - Fareground
• 2024-03-27 | Hawthorne, CA, US | Freeform
  • Rust in the Physical World 🦀 Tech Talk Event at Freeform

Oceania#

• 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#

That would take 18 million terabytes of RAM. You don't have that much memory.

– Alice Ryhl answering "What is MAX array size" on rust-users

Thanks to Zeroexcuses 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