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? Tweet us at @ThisWeekInRust or send us a pull request. Want to get involved? We love contributions.

This Week in Rust is openly developed on GitHub. If you find any errors in this week's issue, please submit a PR.

Updates from Rust Community

Project/Tooling Updates

• rust-analyzer changelog #143
• Slint UI crate weekly updates
• This week in Databend #56: A Modern Cloud Data Warehouse for Everyone
• What's new in axum 0.6.0-rc.1
• HexoSynth Modular Synthesizer in Rust - Devlog #10: Alpha-1 Release
• Fornjot (code-first CAD in Rust) - Weekly Release - 2022-W34

Observations/Thoughts

• Come contribute to Salsa 2022!
• State Machines II

Rust Walkthroughs

• Tauri + Async Rust Process
• Writing a container in Rust
• Experimentally compiling PHP code to Rust - Ryan Chandler
• STM32F4 Embedded Rust at the HAL: GPIO Interrupts
• [video] Rust Traits vs C++ Concepts
• [video] Writing Procedural Macros
• [video] Get under the hood of Rust Language with Assembly!!
• [video] Scoped threads in Rust 1.63
• [video] 1Password Developer Fireside Chat: Demystifying Atomics

Crate of the Week

This week's crate is sass-embedded, a library to communicate with Embedded Dart Sass.

Thanks to Ahab for the self-suggestion.

Please submit your suggestions and votes for next week!

Call for Participation

Always wanted to contribute to open-source projects but didn't 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 - Add syntax highlighting to examples in ockam clap command help using syntect
• Ockam - Add examples section to ockam tcp-inlet create command's help
• Ockam - Make ockam node delete --all --force command more forceful
• Mirrord - Consider using mold linker
• Mirrord - mirrod-layer and mirrord bin are being built twice when running cargo +nightly build

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

Updates from the Rust Project

411 pull requests were merged in the last week

• mitigate stale data reads on SGX platform
• support 128-bit atomics on all aarch64 targets
• rustc_metadata: deduplicate strings to prevent multiple copies in rmeta/query cache blow file size
• make NOP dyn casts not require anything about the vtable
• implied bounds: explicitly state which types are assumed to be wf
• never consider unsafe blocks unused if they would be required with deny(unsafe_op_in_unsafe_fn)
• do not allow Drop impl on foreign fundamental types
• don't derive PartialEq::ne
• lazily decode SourceFile from metadata
• make must_not_suspend lint see through references when drop tracking is enabled
• mention as_mut alongside as_ref in borrowck error message
• point at a type parameter shadowing another type
• recover keywords in trait bounds
• reenable disabled early syntax gates as future-incompatibility lints
• improved diagnostic for function defined with def, fun, func, or function instead of fn
• suggest fn if fun, func, function or def is used to define a function
• suggest once_cell::Lazy for non-const statics
• suggest adding a reference to a trait assoc item
• suggest adding an array length if possible
• suggest the right help message for as_ref
• UnreachableProp: preserve unreachable branches for multiple targets
• kind-less SessionDiagnostic derive
• convert diagnostics in parser/expr to SessionDiagnostic
• migrate "invalid variable declaration" errors to SessionDiagnostic
• migrate emoji identifier diagnostics to SessionDiagnostic in rustc_interface
• migrate lint reports in typeck::check_unused to LintDiagnostic
• migrate more rustc_borrowck diagnostics to SessionDiagnostic
• migrate rustc_ast_passes diagnostics to SessionDiagnostic and translatable messages (first part)
• migrate typeck's used expected symbol diagnostic to SessionDiagnostic
• migrations for rustc_expand transcribe.rs
• migrate some rustc_borrowck diagnostic
• miri: breaking posix_memalign precondition is not UB
• miri: improve information sharing across SB diagnostics
• miri: add very basic Android support
• remove manual implementations of HashStable for hir::Expr and hir::Ty
• shrink ast::Attribute
• box the MacCall in various types
• use AttrVec more
• add IpDisplayBuffer helper struct
• rework Ipv6Addr::is_global to check for global reachability rather than global scope
• make slice::reverse const
• refactor iteration logic in the Flatten and FlatMap iterators
• futures: fix incorrect termination of select_with_strategy streams
• cargo: fix file locking being not supported on Android raising an error
• cargo: improve error message for an array value in the manifest
• cargo: improve error message for wrong target names
• rustdoc: merge source code pages HTML elements together v2
• rustdoc: count deref and non-deref as same set of used methods
• rustdoc: strategic boxing to reduce the size of ItemKind and Type
• rustfmt: Unicode comment align
• clippy: add unused_peekable lint
• clippy: add manual_empty_string_creations lint
• clippy: add new lint positional_named_format_parameters
• clippy: don't lint on match pattern-binding in question_mark
• clippy: enhance needless_borrow to consider trait implementations
• clippy: fix non_ascii_literal in tests
• clippy: fix to_string_in_format_args false positive
• clippy: fix false positives of needless_match
• clippy: lint collapsible_str_replace
• clippy: more lint pass merges
• clippy: refactor FormatArgsExpn
• clippy: rework only_used_in_recursion and move it back to complexity
• clippy: transmute_undefined_repr fix
• clippy: check for if-some-or-ok-else-none-or-err
• clippy: Do not lint needless_collect if the target code is inside a loop
• clippy: suggest map_or in case_sensitive_file_extension_comparisons
• clippy: unwrap_used and expect_used: trigger on uses of their _err variants
• rust-analyzer: consider bounds on inherent impl in method resolution
• rust-analyzer: implement IntoFuture type inference
• rust-analyzer: implement lsp extension for cancelling running flychecks
• rust-analyzer: log rustfmt parsing errors as warnings
• rust-analyzer: pop an error notification when flycheck can't be restarted
• rust-analyzer: add a setting for keyword hover popups
• rust-analyzer: add an assist for inlining all type alias uses
• rust-analyzer: generate static method using Self::assoc() syntax
• rust-analyzer: improved inline_call to replace Self
• rust-analyzer: run test mod from anywhere in parent file
• rust-analyzer: make trait assoc items become inactive due to cfg
• rust-analyzer: fix panics on GATs involving const generics
• rust-analyzer: escape keywords used as names in earlier editions
• rust-analyzer: record completion filtering
• rust-analyzer: resolve associated types of bare dyn types
• rust-analyzer: resolve path Self alone in value namespace
• tidy: check fluent files for style

Rust Compiler Performance Triage

Overall some really impressive wins this week. Note in particular PR #100209, "Lazily decode SourceFile from metadata" (which improved 75 primary benchmark scenarios and 158 secondary scenarios) and PR #98655 "Don't derive PartialEq::ne", which improved 65 primary scenarios and 27 secondary scenarios). There were a few cases that pnkfelix explicitly decided not to mark as triaged; see report for more details there. Also pnkfelix wonders if there is a recent slight-upward trend on max-rss for the past week, see the summary graph

Triage done by @pnkfelix. Revision range: 14a459bf..4a24f08b

Summary:

3 Regressions, 4 Improvements, 4 Mixed; 3 of them in rollups 43 artifact comparisons made in total

Full report

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.

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

• [disposition: merge] Register wf obligation before normalizing in wfcheck
• [disposition: merge] Partially stabilize bound_as_ref by stabilizing Bound::as_ref
• [disposition: merge] Document NonZeroXxx layout guarantees
• [disposition: merge] Strengthen invalid_value lint to forbid uninit primitives, adjust docs to say that's UB
• [disposition: merge] Make forward compatibility lint deprecated_cfg_attr_crate_type_name deny by default

New and Updated RFCs

• [new] RFC: Statics in patterns

Upcoming Events

Rusty Events between 2022-08-24 - 2022-09-21 🦀

Virtual

• 2022-08-24 | Virtual (Beijing, CN) | WebAssembly and Rust Meetup (Rustlang)
  • Tech Talk Live Appointment: Customize GitHub Workflow with Serverless Functions - How to use Rust and JavaScript to automate GitHub processes
• 2022-08-24 | Virtual + Wellington, NZ | Rust Wellington
  • Flywheel Edition: 3 talks on Rust!
• 2022-08-25 | Virtual (Karlsruhe, DE) | The Karlsruhe Functional Programmers Meetup Group
  • Stammtisch: together with the C++ UG KA; various topics, from C++ to Rust
• 2022-08-27 | Virtual (Bangalore, IN) | Polkadot India
  • Substrate Saturday - Bootcamp Series 2: Fundamentals of Rust & Substrate
• 2022-08-30 | Virtual (Berlin, DE) | OpenTechSchool Berlin
  • Rust Hack and Learn
• 2022-08-30 | Virtual + Dallas, TX, US | Dallas Rust
  • Last Tuesday
• 2022-09-01 | Virtual (PDT Timezone) | Conf42
  • Conf42: Rustlang 2022
• 2022-09-01 | Virtual | Google Open Source Live
  • Rust Day on Google Open Source Live
• 2022-09-02 | Virtual (Nürnberg, DE) | Rust Nuremberg
  • Rust Nuremberg Get Together
• 2022-09-03 | Virtual (Bangalore, IN) | Polkadot India
  • Substrate Saturday - Bootcamp Series 2: Fundamentals of Rust & Substrate
• 2022-09-03 | Virtual (Nürnberg, DE) | Rust Nuremberg
  • Deep Dive Session 1: Tokio my-redis Tutorial
• 2022-09-04 | Virtual (Seattle, WA, US) | Seattle Rust Meetup
  • September Meetup
• 2022-09-06 | Virtual (Beijing, CN) | WebAssembly and Rust Meetup (Rustlang)
  • Monthly WasmEdge Community Meeting, a CNCF sandbox WebAssembly runtime
• 2022-09-06 | Virtual (Buffalo, NY, US) | Buffalo Rust Meetup
  • Buffalo Rust User Group, First Tuesdays
• 2022-09-07 | Virtual (Indianapolis, IN, US) | Indy Rust
  • Indy.rs - with Social Distancing
• 2022-09-10 | Virtual | Rust GameDev
  • Rust GameDev Monthly Meetup
• 2022-09-10 | Virtual (Bangalore, IN) | Polkadot India
  • Substrate Saturday - Bootcamp Series 2: Fundamentals of Rust & Substrate
• 2022-09-12 | Virtual + Dublin, IE | Linux Plumbers Conference
  • Rust Microconference in LPC 2022
• 2022-09-13 | Virtual + Dallas, TX, US | Dallas Rust
  • Second Tuesday
• 2022-09-13 | Virtual (Rostock, DE) | Altow Academy
  • Rust Meetup Rostock
• 2022-09-14 | Virtual (Malaysia)| Golang Malaysia
  • Rust Meetup September 2022
• 2022-09-15 | Virtual (Columbus, OH, US) | GDG Columbus
  • Past, Present, and Future of Internet Money! (Custom tokenomics, RUST and CosmWASM library...)
• 2022-09-20 | Virtual (Washington, DC, US) | Rust DC
  • Mid-month Rustful
• 2022-09-21 | Virtual (Vancouver, BC, CA) | Vancouver Rust
  • Rust Study/Hack/Hang-out (Call for Participation)

Europe

• 2022-08-25 | Copenhagen, DK | Copenhagen Rust group
  • CPH Hack Night #28
• 2022-08-25 | Stockholm, SE | StockholmCpp
  • 0x21: Learning from Rust, Typical C++
• 2022-08-30 | Utrecht, NL | Rust Nederland
  • Run Rust Anywhere
• 2022-09-12 | Dublin, IE + Virtual | Linux Plumbers Conference
  • Rust Microconference in LPC 2022

North America

• 2022-08-23 | Toronto, ON, CA | Rust Toronto
  • WebAssembly plugins in Rust
• 2022-08-25 | Ciudad de México, MX | Rust MX
  • Concurrencia & paralelismo con Rust
• 2022-08-25 | Lehi, UT, US | Utah Rust
  • Using Github Actions to Deploy Cargo Crates with Jordan and Food!
• 2022-08-31 | New York, NY, US | Rust NYC
  • August Meetup: Rewriting a high performance Vector Database in Rust.

Oceania

• 2022-08-24 | Wellington, NZ + Virtual | Rust Wellington
  • Flywheel Edition: 3 talks on Rust!
• 2022-08-26 | Melbourne, VIC, AU | Rust Melbourne
  • August 2022 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

A fast executing language that crashes all the time is like a supercar… that crashes all the time.

– Tris on youtube

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.

Email list hosting is sponsored by The Rust Foundation

Discuss on r/rust