Rust's custom allocators are moving closer to stabilization after six months of renewed effort led by Nia and the libs team. The Allocator trait now supports dynamic dispatch (dyn Allocator) and integrates with Vec and Box, though the initial API surface is intentionally limited to ensure soundness. The stabilization prohibits unwinding from allocators and excludes certain container types and methods pending further work.
The never type in Rust has been stabilized on nightly after 10 years of instability, 5 previous failed attempts, and over 2 years of personal work by the author.
Rust's custom allocators have progressed significantly toward stabilization, with a simplified API surface consisting of two core Allocator trait methods and support for Vec and Box. Major improvements include making Allocator dyn-compatible for dynamic dispatch and strengthening safety guarantees by prohibiting unwinding from allocators, though this first release is positioned as an MVP with further work needed for full container support.
Rust stabilized its never type (!) after over two years of work, allowing functions that never return to be properly typed. The feature enables compiler optimizations for generic code and simplifies type inference for constructs like infinite loops.