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Rust 1.99.1 restores wcslen and fixes x86_64 FFI bool returns

blog.rust-lang.org Editor score 7/10

The point release fixes missing wcslen symbols on some targets and a miscompilation of bool return values across x86_64 FFI. These regressions matter to teams shipping Rust across targets or relying on C interoperability.

What

Rust 1.99.1 is a point release that fixes regressions involving `wcslen`, FFI `bool` returns on x86_64 and rust-lld on macOS.

How

The release adds a `wcslen` fallback, restores zero-extension for FFI `bool` returns, and gives rust-lld an rpath to find libLLVM.

Why it matters

The fixes address linking and ABI problems that can break Rust projects across targets and when calling functions through FFI.

Read on blog.rust-lang.org → Lobsters · 5 comments

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