NixOS/nixpkgs — pull request #3668 by rrnewton (2014-08-19 06:44:12+00:00)
Title: Bump ghc-head to latest.

This is just a small bump forward for GHC head.

Motivation: Johan Tibell added several new primps for atomic memory operations. Having a nix pkg for a build of GHC including these will make it easier to get these changes to people to test/benchmark them.