The compiler team had our weekly triage meeting on 2019-10-10. You can find the minutes on the compiler-team repository. Each week, we have general announcements from the team followed by check-ins from two of the compiler team working groups.

Announcements

@centril is splitting libsyntax into data and logic parts which will decrease the amount of code librustc depends on.

@nagisa is working on a cross-platform version of stacker which will allow us to avoid stack overflows in rustc.

There is a compiler team design meeting scheduled for tomorrow (2019-10-11) to discuss some of @Zoxc's PRs.

@pnkfelix is revising the code that handles structural match checking.

@nikomatsakis has a PR (#65232) up which helps us get closer to lazy normalization.

wg-traits is going to start holding a weekly "office hours" video call to help answer questions and teach people about trait system internals.

Working group sync

wg-rustc-dev-guide aims to make the compiler easier to learn by ensuring that rustc-dev-guide and api docs are “complete”.

wg-rustc-dev-guide has been working on transcribing videos from the compiler lecture series into rustc-dev-guide chapters.

Originally, individuals were assigned one or lectures to complete but that hasn't worked very well.

Recently, they're trying to work on one video at a time as a team with much better results.

There's a PR open for a new chapter based on the ty lecture.

Link to full discussion

wg-llvm encompasses work in LLVM upstream fixing the issues and implementing features that matter to Rust.

rustc has upgraded to the LLVM 9 release; Which allows us to replace some the emscripten stuff with LLVM’s toolchain. As part of these upgrades we will likely end up dropping support for the super old LLVM 6, which in turn allows us to stop building the unnecessary Go & OCaml bindings to LLVM, which in turn helps rustc build times slightly.

People are also working on enabling use of the new pass manager, which might give us some tangible code quality improvements over the status quo.

Link to full discussion