• @simulacrum landed the rustc-dev split PR which decreases the size of the rustc-dev rustup component #65474

Backport nominations

  • Avoid ICE when adjusting bad self ty #65755

    • Accepted for beta and stable backport
  • Avoid ICE when checking Destination of break inside a closure #65518

    • Accepted for beta and stable backport
  • save-analysis: Nest tables when processing impl block definitions #65511

    • Accepted for beta backport
  • save-analysis: Don’t ICE when resolving qualified type paths in struct members #65353

    • Accepted for beta backport

Working group sync


  • Rust 1.40 (current nightly) will be the first stable release without the HIR borrow checker. This means Non Lexical Lifetimes will be available on Rust 2015.

  • At this point, wg-nll has completed its purpose and will be disbanded.

    • wg-polonius is still going strong though!

Link to full discussion


  • Work is proceeding slowly but steadily. There are regular triage meetings every Monday on the compiler calendar.

  • The current goal is to refactor/audit compiler locks and other parts of the parallel query system and to investigate improving performance.

  • The current MVP is to do high-level parallelization in a few critical places such as typechecking & linting.

  • Currently, we’re not seeing the speedups we want from parallelization but work is ongoing to remove locking and improve the jobserver integration.

  • Video recording of last meeting

Link to full discussion