Rust 1.68.0 released

Version1.68.0 of the Rust language has been released. Changes include thestabilization of the "sparse" Cargo protocol, the ability for (some)applications to recover from memory-allocation failures, and "local Pinconstruction":

The new pin! macro constructs aPin<&mut T> from a T expression,anonymously captured in local state. This is often calledstack-pinning, but that "stack" could also be the captured state ofan async fn or block.