2026-07-13 — Last Week in Carbon

[josh11b]

News

• Recorded version of memory safety deep dive is now available: video, transcript, slides (press 's' for speaker notes)
• Major update to binding syntax is now implemented in the toolchain (#7479)

Updates on leads issues

• Decisions
  • (none)
• New issues
  • #7466 reconsider the `PackageName//library-name` pseudo-syntax
• Active discussions
  • (none)

Updates on proposals

• Decisions
  • (none)
• New RFC proposals
  • (none)
• Active discussions
  • #7437 Reject nested `where` expressions to prevent ambiguous `.Self`
    • Should we syntactically restrict where where can appear?

Updates on moderation across our community spaces (Discord and GitHub)

• Conduct team updates:
  • WIP: transparency report for the past quarter
• Moderation interventions last week:
  • A Discord user was banned after posting job searching messages in several channels, with no relation to our project, disregarding our community rules. Both messages were deleted in the process.
• Activity in the past week:
  • BLOCKED: new landing page mockup that would incorporate self-learning quizzes in #7237
  • BLOCKED: discussing creating self-learning quizzes around the language, alongside more community culture-oriented ones.
  • WIP: drafting explicit more standards for using LLMs in the project
  • 7 authors have pushed 30 commits to trunk.
  • 1,257 files have changed and there have been 42,906 additions and 25,057 deletions
  • We merged 30 PRs, opened 7 additional PRs, closed no issue, and opened 1 new issue.

Activity on toolchain

• 07-07 prelude
• 07-07 Markdown formatter
• #pattern-matching Should we reject struct field patterns without names during parsing?
• #interop How to interoperate with Rust libraries
• #interop Constructor interop & reverse interop
• #llvm Constructors in LLVM IR and Clang AST
• #toolchain latest_decl_id() needs to change to handle the fact that an impl can be redeclared in a match_first after its definition
• PRs:
  *
  • bracket lexing in #7457
  • compile benchmarks in #7459 #7465 #7456
  • subst and .Self in #7452 #7449 #7443 #7477 #7471 #7460 #7474 #7461
  • bindings in #7467 #7468 #7479
  • 07-07 exporting generic Carbon functions to C++ in #7462
  • observe in #6709
  • match_first in #7478 #7480 #7481 #7482
  • impl lookup in #7454
  • dev infra in #7483 #7470
  • #llvm others in #7463 #7473 #7476 #7485

Activity on memory safety

• 07-07 Design of a safe alloc api for core, and of raw storage which it depends on. Use an “init pattern” to use an initializing expression to initialize into an existing raw storage location.
• #safety How to describe how C++ misbehavior can affect Carbon's safety?
• #safety Interesting external discussion flagging some issues Rust ran into, especially with variance.

Other active discussions

These include Discord Chat, GitHub Discussions, or open discussion sessions.

• #infra Can we add clangd-format to the local pre-commit?
• #infra Fixed some permissions on our gcloud project.
• #contributing-help rumdl not wrapping lines.
• #error-handling Migration target for macros like ABSL_ASSIGN_OR_RETURN.
• #infra CI failures with "error running git fetch"
• #contributing-help Trouble building from trunk due to relocation errors.
  • The system libunwind needs to be version 19.
• #generics-and-templates Using .Self-thawing as a way to check for the presence of .Self in a non-facet type.
• #generics-and-templates Behaviour of observe and impl lookup/deduce which can now do multiple steps of lookup.
• #proposals-prs-and-process Can we use toolchain implementation to justify language proposals?
  • Yes.
• 07-09 Migration target for VLOG:
  • Deferred argument evaluation
  • Formatted string literals
• #language-questions What does "Pattern matching as function overload resolution" mean?
• #editor-integrations External team planning to work on Carbon support in IJ in February/March.
• #contributing-help Carbon can link using Wild, and it seems to dramatically improve link time.
• #general-design Omitting parentheses around if and for

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[dongweigogo]

Has the 'place set', the core part of the memory safety design, been implemented in the toolchain?

[danakj]

No, we haven't started implementing the memory safety design yet