Who contributed to Rust on May 23, 2026?

1 developer shipped this update, including JonathanBrouwer.

What were the notable Rust updates?

Rollup of 10 pull requests, Rollup merge of #156815 - fee1-dead-contrib:rustfmt-const-traits, r=ytmimi, and Rollup merge of #156725 - P8L1:fix/rtn-assoc-ty-parentheses-diagnostic, r=jackh726.

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RUSTFMT PIVOTS TO CONST IMPL SYNTAX AS COMPILER HARDENS FEATURE GATES

By RepoJournal · Filed 06:04 UTC on May 23, 2026 · About Rust

1 person shipped this

JonathanBrouwer @JonathanBrouwer 1 cited

Rust's formatter shipped a syntax transition PR ahead of the next beta, moving const trait impls from `impl const Trait` to `const impl Trait` to align with upcoming parser changes in the compiler.

The rollup landed 10 PRs across the compiler pipeline [1], including a critical rustfmt update [2] that reformats const trait implementations to the new `const impl` syntax. This move is intentional: rustc is dropping parser support for the old `impl const Trait` form in the next beta, so rustfmt needs to lead the transition now. In parallel, the compiler tightened its debug info handling [1] to gracefully fail on invalid `String` and `Vec` representations, and fixed a long-standing RTN FIXME that no longer applies now that return type notation uses `(..)` syntax [3]. The docs pipeline also got a quality-of-life improvement: traits that ARE dyn compatible now show a "Dyn Compatibility" section, not just the ones that aren't [4]. On the analyzer front, rust-analyzer merged fixes for named consts in range pattern types [5] and added clearer error reporting for unimplemented builtin macros [6], both addressing gaps in IDE diagnostics that were confusing developers. All of this landed on the heels of a crates.io index push for mockforge-security-core [7], the security-focused test harness suite.

Action items

→ Update rustfmt configurations if you've pinned const trait syntax; the new `const impl` form is now the standard rust-lang/rust [plan]
→ Verify your range pattern type usage with the latest rust-analyzer if you rely on named const bounds rust-lang/rust-analyzer [monitor]
→ Review the Windows LLVM DLL changes if you build on Windows; this is required for the next nightly rust-lang/rust [plan]

References

[1] Rollup of 10 pull requests ↗ rust-lang/rust
[2] Rollup merge of #156815 - fee1-dead-contrib:rustfmt-const-traits, r=ytmimi rust-lang/rust
[3] Rollup merge of #156725 - P8L1:fix/rtn-assoc-ty-parentheses-diagnostic, r=jackh726 rust-lang/rust
[4] Auto merge of #156835 - yotamofek:pr/positive-dyn-compatible, r=fmease rust-lang/rust
[5] Merge pull request #22396 from ChayimFriedman2/pat-ty-const rust-lang/rust-analyzer
[6] Merge pull request #22383 from ChayimFriedman2/unimplemented-builtin rust-lang/rust-analyzer
[7] Update crate `mockforge-security-core` rust-lang/crates.io-index

Quick answers

What shipped in Rust on May 23, 2026?: Rust's formatter shipped a syntax transition PR ahead of the next beta, moving const trait impls from `impl const Trait` to `const impl Trait` to align with upcoming parser changes in the compiler. In total, 75 commits, 12 pull requests, and 1 releases landed.
Who contributed to Rust on May 23, 2026?: 1 developer shipped this update, including JonathanBrouwer.
What were the notable Rust updates?: Rollup of 10 pull requests, Rollup merge of #156815 - fee1-dead-contrib:rustfmt-const-traits, r=ytmimi, and Rollup merge of #156725 - P8L1:fix/rtn-assoc-ty-parentheses-diagnostic, r=jackh726.

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