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

Foundation

• Hello JFrog!

Newsletters

• This Month in Rust OSDev: August 2022

Project/Tooling Updates

• Announcing Unreal Rust
• Introducing cxx-async
• Arti 1.0.0 is released: Our Rust Tor implementation is ready for production use
• rust-analyzer changelog #145
• rustc_codegen_gcc: Progress Report #15
• Lapce editor 0.2.0 released
• This week in Databend #58: A Modern Cloud Data Warehouse for Everyone
• HexoSynth 2022 - Devlog #11: VST3/CLAP Plugin Integration
• Fornjot (code-first CAD in Rust) - Weekly Release - 2022-W36
• One year of Relm4
• Slint UI crate weekly updates

Observations/Thoughts

• How to Use Rust Traits, Generics and Bounds
• Wasmtime 1.0: A Look at Performance
• Understanding primitive data types in Rust
• [video] RustConf 2022 Talks
• [video] Rust Education Workshop 2022
• [audio] Fyrox with Dmitry Stepanov

Rust Walkthroughs

• Filtering a Vector with SIMD Instructions (AVX-2 and AVX-512)
• Learning Rust: Async Combinators
• Solving The Witness with Z3 (Part 2)
• How to build a (simple) blog using Rust
• STM32F4 Embedded Rust at the HAL: The RTIC Framework
• [video] Nine Rules for Elegant Rust Library APIs

Miscellaneous

• [DE] Security: FreeBSD-Kernel bekommt experimentelle Rust-Patches

• Random File Lines and Iterator Items: Understanding Reservoir Sampling with Rust

Crate of the Week

This week's crate is sql-query-builder, a library to write SQL queries in a simple and composable way.

Thanks to Belchior Oliveira 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 - Show ockam command help in $PAGER or less (clap based)
• Ockam - Detect new release is available and display upgrade instructions in ockam command
• Ockam - Remove the --node argument from ockam enroll clap command

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

Updates from the Rust Project

417 pull requests were merged in the last week

• add tier-3 support for powerpc64 and riscv64 openbsd
• support #[unix_sigpipe = "inherit|sig_dfl"] on fn main() to prevent ignoring SIGPIPE
• proc_macro/bridge: send diagnostics over the bridge as a struct
• proc_macro/bridge: use the cross-thread executor for nested proc-macros
• do not leak type variables from opaque type relation
• attempt to normalize FnDef signature in InferCtxt::cmp
• do not report too many expr field candidates
• do not suggest adding move to closure when move is already used
• don't suggest reborrow if usage is inside a closure
• suggest {Option,Result}::{copied,clone}() to satisfy type mismatch
• suggest associated method on deref types when path syntax method fails
• suggest moving redundant generic args of an assoc fn to its trait
• suggest returning closure as impl Fn
• add special_module_name lint
• uplift the let_underscore lints from clippy into rustc
• strengthen invalid_value lint to forbid uninit primitives, adjust docs to say that's UB
• forbid mixing System with direct sytem allocator calls
• use head span for rustc_on_unimplemented's enclosing_scope attr
• make call suggestions more general and more accurate
• make trait bound not satisfied specify kind
• miri: adjust for supporting more implicit ptr-to-int transmutation
• miri: re-enable FFI support
• allow deriving multipart suggestions
• replace rustc_data_structures::thin_vec::ThinVec with thin_vec::ThinVec
• separate the receiver from arguments in HIR
• shrink thir::Pat
• shrink suggestion span of argument mismatch error
• simplify hir::PathSegment
• interpret: fix unnecessary allocation in validation visitor
• more clippy::perf fixes
• optimization of access level table construction
• migrate rustc_session to use SessionDiagnostic - Pt. 1
• migrate rustc_metadata to SessionDiagnostics
• migrate rustc_monomorphize to use SessionDiagnostic
• porting 'compiler/rustc_trait_selection' to translatable diagnostics - Part 1
• fix UB from misalignment and provenance widening in std::sys::windows
• avoid needless buffer zeroing in std::sys::windows::fs
• avoid zeroing large stack buffers in stdio on Windows
• add AsFd implementations for stdio types on WASI
• implement internal IsZero for Wrapping and Saturating for Vec optimizations
• add vec::Drain{,Filter}::keep_rest
• fix into_iter on ZST
• provider API: add additional methods to the Demand type
• make ReentrantMutex movable and const
• make char::is_lowercase and char::is_uppercase const
• make const_eval_select a real intrinsic
• hashbrown: Equivalent trait
• cargo: rework test error handling
• clippy: add --explain subcommand
• clippy: new lint bool_to_int_with_if
• clippy: initial implementation result_large_err
• clippy: don't use hir_ty_to_ty in result_large_err
• clippy: use approx_ty_size for large_enum_variant
• clippy: fix mut_mutex_lock when mutex is behind immutable deref
• clippy: fix suboptimal_float not linting on {const}.powf({const})
• clippy: fix unnecessary_to_owned false positive
• clippy: fix missing parens in suboptimal_flops suggestion
• clippy: fix the emission order of trait_duplication_in_bounds
• clippy: suggest Entry::or_default for Entry::or_insert(Default::default())
• rust-analyzer: clarify the state of (extern) preludes for block def maps
• rust-analyzer: don't store SyntheticSyntax in the reverse maps in BodySourceMap
• rust-analyzer: drop the expander borrow in all control flow paths
• rust-analyzer: fix nested break expressions, expecting unknown types
• rust-analyzer: highlight namerefs by syntax until proc-macros have been loaded
• rust-analyzer: lift out the module scope into a field in the resolver
• rust-analyzer: prefer the type of expression in "Replace turbofish with type"
• rust-analyzer: properly handle break resolution inside non-breakable expressions
• rust-analyzer: remove hir::Expr::MacroStmts
• rust-analyzer: remove type alias definition on inline
• rust-analyzer: suggest struct when completing enum
• rust-analyzer: add a "Unmerge match arm" assist to split or-patterns inside match expressions
• rust-analyzer: implement feature(exhaustive_patterns) from unstable Rust
• rust-analyzer: assist to turn match into matches! invocation
• rust-analyzer: insert whitespaces into static & const bodies if they are expanded from macro on hover
• rust-analyzer: lower float literals with underscores
• rust-analyzer: only move comments when extracting a struct from an enum variant
• rust-analyzer: parse TypePathFn with preceding ::
• rust-analyzer: correct broken logic for return completion
• rust-analyzer: unescape all occurrences of module name in module resolution

Rust Compiler Performance Triage

A relatively quiet week where regressions unfortunately outweighed improvements. What's more, many of the regressions that were found seemed somewhat mysterious requiring some deeper investigations.

Triage done by @rylev. Revision range: 0631ea5d73..09fb0bc6e

Summary:

2 Regressions, 3 Improvements, 2 Mixed; 3 of them in rollups 40 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

• [disposition: merge] De-RFC: Remove type ascription

Tracking Issues & PRs

• [disposition: merge] Stabilize generic associated types
• [disposition: merge] Fix handling of trailing bare CR in str::lines
• [disposition: merge] Implement Default for some alloc/core iterators
• [disposition: merge] Tracking Issue for #[instruction_set] attribute (RFC 2867)
• [disposition: merge] Consider #[must_use] annotation on async fn as also affecting the Future::Output
• [disposition: merge] Tracking issue for ..X, and ..=X (#![feature(half_open_range_patterns)])

New and Updated RFCs

• [new] RFC: Add descriptive names to doctest
• [new] Add a general mechanism of setting RUSTFLAGS in Cargo for the root crate only
• [new] Rust Style Team
• [new] Add core::mem::offset_of! RFC

Upcoming Events

Rusty Events between 2022-09-07 - 2022-10-05 🦀

Virtual

• 2022-09-07 | Virtual (Indianapolis, IN, US) | Indy Rust
  • Indy.rs - with Social Distancing
• 2022-09-08 | Virtual (Linz, AT) | Rust Linz
  • Workshop: Introduction To Rust For Artists - by Lisa Passing
• 2022-09-08 | Virtual (Nürnberg, DE) | Rust Nuremberg
  • Rust Nürnberg online #17
• 2022-09-09 | Virtual + Linz, AT | Rust Linz
  • Rust Meetup Linz - 25th Edition
• 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 (Sep 12-14)
• 2022-09-13 | Virtual (Berlin, DE) | OpenTechSchool Berlin
  • Rust Hack and Learn
• 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 (Boulder, CO, US) | Boulder Elixir and Rust
  • Monthly Meetup
• 2022-09-14 | Virtual (Cardiff, UK) | Rust and C++ Cardiff
  • Introduction to Async in Rust
• 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...)
• 2022-09-15 | Virtual (Stuttgart, DE) | Rust Community Stuttgart
  • Rust-Meetup
• 2022-09-20 | Virtual (Washington, DC, US) | Rust DC
  • Mid-month Rustful: Bencher—Catch Performance Regressions in CI—Everett Pompeii
• 2022-09-21 | Virtual (Vancouver, BC, CA) | Vancouver Rust
  • Rust Study/Hack/Hang-out (Call for Participation)
• 2022-09-22 | Virtual (Charlottesville, VA, US) | Charlottesville Rust Meetup
  • Rust based Bluetooth tools (BlueR) you can use today
• 2022-09-23 | Virtual (Tokyo, JP) | Rust Tokyo
  • Rust Tokyo 2022
• 2022-09-27 | Virtual (Dallas, TX, US) | Dallas Rust
  • Last Tuesday
• 2022-10-04 | Virtual (Buffalo, NY, US) | Buffalo Rust Meetup
  • Buffalo Rust User Group, First Tuesdays
• 2022-10-05 | Virtual (Indianapolis, IN, US) | Indy Rust
  • Indy.rs - with Social Distancing
• 2022-10-05 | Virtual (Stuttgart, DE) | Rust Community Stuttgart
  • Rust-Meetup

Europe

• 2022-09-09 | Linz, AT + Virtual | Rust Linz
  • Rust Meetup Linz - 25th Edition
• 2022-09-12 | Dublin, IE + Virtual | Linux Plumbers Conference
  • Rust Microconference in LPC 2022 (Sep 12-14)
• 2022-09-13 | Rome, IT | Rust Roma
  • Rust learning and hacking evening #Aperitech
• 2022-09-15 | Paris, FR | Rust Paris
  • Rust Paris meetup #52
• 2022-09-29 | Amsterdam, NL | Rust Developers Amsterdam Group
  • Fiberplane Rust Workshop
• 2022-09-29 | Copenhagen, DK | Copenhagen Rust group
  • Rust Hack Night #29
• 2022-09-29 | Enschede, NL | Dutch Rust Meetup
  • Going full stack on Rust
• 2022-10-02 | Florence, IT + Virtual | RustLab
  • RustLab Conference 2022 (Oct 2-4)

North America

• 2022-09-08 | Columbus, OH, US| Columbus Rust Society
  • Monthly Meeting
• 2022-09-14 | Austin, TX, US | Rust ATX
  • Rust Lunch
• 2022-09-20 | San Francisco, CA, US | San Francisco Rust Study Group
  • Rust Hacking in Person
• 2022-09-22 | Lehi, UT, US | Utah Rust
  • Game Prototyping with Rusty Engine with Nathan Stocks and Food!

Oceania

• 2022-09-14 | Sydney, NSW, AU | Rust Sydney
  • Rust-Sydney Lightning Talks

South America

• 2022-09-10 | São Paulo, BR | Rust São Paulo Meetup
  • iFood Tech Day: Rust

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

So long, and thanks for all the turbofish.

– moltonel on r/rust

Thanks to Josh Triplett 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