[Nix-dev] gcc for MacOS X

[Peter Simons]

Hi Ludovic,

when lipo is added to stdenv, then use of the darwinLipoUtility
attribute should be removed from all-packages.nix, too.

Furthermore, one might argue that all of the following utilities should
be moved into Darwin stdenv as well:

  darwinArchUtility = callPackage ../os-specific/darwin/arch { };

  darwinSwVersUtility = callPackage ../os-specific/darwin/sw_vers { };

  darwinInstallNameToolUtility = callPackage ../os-specific/darwin/install_name_tool { };

Take care,
Peter