Rust: Bootstrap Cleanup and Coverage Comes Back
A dense day of rollups consolidated bootstrap internals, dependency upgrades, and diagnostic cleanups, while MC/DC coverage instrumentation returned to the compiler in a two-part landing.
Duration: PT2M41S
Episode overview
This episode is a short developer briefing from Rust.
It explains recent repository work in plain language.
- Show: Rust
- Published: 2026-08-17T13:09:11Z
- Audio duration: PT2M41S
Transcript excerpt
This excerpt keeps the crawler page concise. Listen to the episode or use the RSS feed for the full update.
Good morning, it's August 17th, and here's what moved in the Rust compiler.
The dominant thread today is bootstrap housekeeping. Zalathar landed a trio of related changes: PR 161157 moved several items out of bootstrap's crate root, PR 161219 followed up by making various internals non-public to catch dead code, and PR 161173 fixed a tidy check that was incorrectly scanning any file path…
Second theme: diagnostics are getting quieter and more precise. RalfJung's PR 161193 strips pointless spans from partial-mitigations errors, following the same pattern as PR 161183 for target modifier errors, both of which landed in today's rollups. RalfJung also opened PR 161238, removing a legacy…
Third: dependency and subtree churn. Cuviper's PR 160529 upgraded and deduplicated key crates, including getrandom, gimli, and object, cutting transitive dependencies. That rode along in multiple rollups today. Separately, compiler-builtins, miri, rust-analyzer, and rustc_codegen_cranelift all got subtree syncs,…
The other big feature news: MC/DC coverage instrumentation is being reintroduced in stages. PR 161223 handles MIR instrumentation and PR 161224 finalizes codegen, wiring boolean expression…
Two…
Nearby episodes from Rust
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- Weekly Recap - Bootstrap Cleanup, Trait Solver Performance, and Compiler Governance
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