Rust 1.80.1 Fixes: Miscompilation, False Positives, and More

The Rust team has published a new point release of Rust, 1.80.1. Rust is a programming language that is empowering everyone to build reliable and efficient software. If you have a previous version of Rust installed via rustup, getting Rust 1.80.1 is as easy as: rustup update stable rustup update stable If you don't have it already, you can get rustup from the appropriate page on our website. get rustup What's in 1.80.1 Rust 1.80.1 fixes two regressions that were recently reported. Miscompilation when comparing floats In addition to the existing optimizations performed by LLVM, rustc is growing its own set of optimizations. Rust 1.78.0 added a new one, implementing "jump threading" (merging together two adjacent branches that perform the same comparison). "jump threading" The optimization was also enabled on branches checking for floating point equality, but it didn't implement the special rules needed for floats comparison (NaN != NaN and 0.0 == -0.0). This caused the optimization to miscompile code performing those checks. NaN != NaN 0.0 == -0.0 Rust 1.80.1 addresses the problem by preventing the optimization from being applied to float comparisons, while retaining the optimization on other supported types. False positives in the dead_code lint dead_code Rust 1.80.0 contained refactorings to the dead_code lint. We received multiple reports that the new lint implementation produces false positives, so we are reverting the changes in Rust 1.80.1. We'll continue to experiment on how to improve the accuracy of dead_code in future releases. dead_code dead_code Contributors to 1.80.1 Many people came together to create Rust 1.80.1. We couldn't have done it without all of you. Thanks! Thanks! The Rust Release Team The Rust Release Team Also published here Also published here here Photo by Tim Mossholder on Unsplash Photo by Tim Mossholder on Unsplash Tim Mossholder Unsplash