T-compiler Meeting Agenda 2023-08-03

Announcements

• Today release of rust stable 1.71.1
• We’re rolling the T-compiler leads!. Congrats @davidtwco !
• @apiraino signal boot for Zulip topic at #t-compiler>Refreshing WG checkins in T-compiler triage meeting about refreshing the WG checkins rotation list, thanks!
• Reminder: if you see a PR/issue that seems like there might be legal implications due to copyright/IP/etc, please let us know (or at least message @davidtwco or @Wesley Wiser so we can pass it along).

Other WG meetings (calendar link)

• Types team meeting at time:2023-08-07T10:00:00-04:00
• [Types] Rotating new solver / formality / polonius deep dive at time:2023-08-07T11:00:00-04:00

MCPs/FCPs

• New MCPs (take a look, see if you like them!)
  • “Add builtin:$path option to the -L flag” compiler_team#659 (Zulip)
• Old MCPs (stale MCP might be closed as per MCP procedure)
  • None at this time
• Old MCPs (not seconded, take a look)
  • “Cell Broadband Engine SPU support” compiler_team#614 (Zulip)
  • “Add support for Zephyr OS” compiler_team#629 (Zulip)
  • “Consistently use "region" terminology in later stages of the compiler” compiler_team#634 Zulip
  • “Add a new --build-id flag to rustc” compiler_team#635 (Zulip)
  • “Add support for visionOS targets” compiler_team#642 (Zulip)
  • “Add illumos Tier3 targets” compiler_team#644 (Zulip)
  • “Migrate away from u32 as an offset/length type” compiler_team#647 (Zulip)
• Pending FCP requests (check your boxes!)
  • “Retire the mailing list and make all decisions on zulip” compiler_team#649 (Zulip)
  • “Support overriding warnings level for a specific lint via command line” rust#113307
  • “Stabilize PATH option for --print KIND=PATH” rust#114183
• Things in FCP (make sure you’re good with it)
  • “Revise error code documentation standard” compiler_team#615 (Zulip)
  • “Add a blanket flag to enable/disable codegen UB checks” compiler_team#625 (Zulip)
  • “Report all lints, even if other errors already occurred.” compiler_team#633 (Zulip)
  • “[MCP] proposing a macros working group” compiler_team#637 (Zulip)
  • “Disallow non-identifier-valid –extern crate names " compiler_team#650 (Zulip)
  • “Windows support schedule 2024” compiler_team#651 (Zulip)
  • “New tier-3 targets for TEEOS” compiler_team#652 (Zulip)
  • “Add option to pass environment variables” compiler_team#653 (Zulip)
  • “Expose default_hidden_visibility as a rustc command line option” compiler_team#656 (Zulip)
  • “Add tidy rule against issue-[0-9]+.rs tests” compiler_team#658 (Zulip)
• Accepted MCPs
  • “Use FieldIdx all the way down” compiler_team#639 (Zulip)
  • “Add support for the riscv64-linux-android target” compiler_team#640 (Zulip)
  • “Implement alignment and size niches for references” compiler_team#641 (Zulip)
  • “Changes to StatementKind::Coverage” compiler_team#645 (Zulip)
  • “KRabcake SANitization (KRSAN) mode” compiler_team#646 (Zulip)
  • “Drop MIPS to tier 3” compiler_team#648 (Zulip)
  • “Amend target policy to require codegen support” compiler_team#655 (Zulip)
• Finalized FCPs (disposition merge)
  • “Add documentation on v0 symbol mangling.” rust#97571
  • “make noop_method_call warn by default” rust#111916
  • “Support interpolated block for try and async” rust#112953
  • “Infer type in irrefutable slice patterns with fixed length as array " rust#113199
  • “discard default auto trait impls if explicit ones exist (rebase of #85048)” rust#113312

WG checkins

• @_WG-rls2.0 by @Lukas Wirth (previous checkin)

  Nothing to report

• @_WG-self-profile by @mw and @Wesley Wiser (previous checkin)

  Checkin text

Backport nominations

T-compiler stable / T-compiler beta

• :beta: [1.72.0] “Rename and allow cast_ref_to_mut lint” rust#113422
  • Part of the work on #111567 (uplifting the clippy::cast_ref_to_mut lint into rustc, comment)
  • Renames the lint cast_ref_to_mut -> invalid_reference_casting
  • Temporarily change the default from deny-by-default to allow-by-default until #112431 is merged
  • I-lang-nominated and a T-lang discussion seems to not have happened but @scottmcm agrees (comment)
  • Nominated by @nils (Nilstrieb) (comment)

• No stable nominations for T-compiler this time.

PRs S-waiting-on-team

T-compiler

• Other issues in progress or waiting on other teams

Issues of Note

Short Summary

• 0 T-compiler P-critical issues
  • 0 of those are unassigned
• 54 T-compiler P-high issues
  • 26 of those are unassigned
• 0 P-critical, 1 P-high, 3 P-medium, 1 P-low regression-from-stable-to-beta
• 0 P-critical, 0 P-high, 3 P-medium, 2 P-low regression-from-stable-to-nightly
• 0 P-critical, 34 P-high, 100 P-medium, 18 P-low regression-from-stable-to-stable

P-critical

T-compiler

• No P-critical issues for T-compiler this time.

T-types

• No P-critical issues for T-types this time.

T-rustdoc

• No P-critical issues for T-rustdoc this time.

P-high regressions

P-high beta regressions

• “the trait bound &[u8]: std::convert::From<&[_; 0]> is not satisfied” rust#113238
  • probably P-high, the beta regression breaks a few crates
  • root cause seems to be #106704. As a temporary hotfix to avoid this hitting stable, downgraded the crate addr2line in the std (comment) in 1dcfc26. A durable solution needs to be implemented (comment)

Unassigned P-high nightly regressions

• No unassigned P-high nightly regressions this time.

Performance logs

N/A this week

Nominated Issues

T-compiler

• “MSVC and rustc disagree on minimum stack alignment on x86 Windows” rust#112480
  • Discussed in the past meetings (here and here), left nominated for further discussion (maybe in a separate session)
• ““Legacy” tier 2 targets have misplaced or absent maintainer docs” rust#113739
  • Discussed in the past meeting (here), left nominated for further discussion (maybe in a separate session)

RFC

• No I-compiler-nominated RFCs this time.

Oldest PRs waiting for review

T-compiler

• “Tait must be constrained if in sig” rust#113169 (last review activity: about 27 days ago)
  • cc @oli (appointed as self reviewer)
• “Report allocation errors as panics, second attempt” rust#112331 (last review activity: about 26 days ago)
  • cc: @bjorn3 (T-libs also in the review loop)
• “riscv: Make ELF flags RVE-aware” rust#112567
  • @Nikita Popov can you have a look when you have a sec.?
• “Add Future::map"rust#111347
  • I-async-nominated: anyone from the WG here with news?

Next week’s WG checkins

• @_WG-async-foundations by @nikomatsakis and @tmandry
• Generic Associated Types initiative by @Jack Huey

Next meetings' agenda draft: https://hackmd.io/wkRqXjx5RGGJlHIBuCyEwQ