rust-lang/rust — pull request #18127 by alexcrichton (2014-10-17 18:02:25+00:00)
Title: alloc: Make deriving more friendly with Arc

This adds impls of Eq/Ord/PartialEq/PartialOrd/Show/Default to Arc, and it
also removes the `Send + Sync` bound on the `Clone` impl of Arc to make it more
deriving-friendly. The `Send + Sync` requirement is still enforce on
construction, of course!