NixOS/nixpkgs — pull request #4235 by jwiegley (2014-09-23 16:50:36+00:00)
Title: darwin: Use xcrun to determine the DEPLOYMENT_TARGET

Setting it to 10.6 on 10.9 systems using Xcode 6.0.1 no longer works. @peti @edolstra Note: This will cause the world to rebuild, so I think this belongs on another branch?