anchor.diff:      # makes it slower, but during runtime we link against just mesa_drivers
       # through /run/opengl-driver*, which is overriden according to config.grsecurity
       # grsecEnabled = true; # no more support in nixpkgs ATM
  -
  -    llvmPackages = llvmPackages_5;
     });
   
     mesa_glu =  mesaDarwinOr (callPackage ../development/libraries/mesa-glu { });
  
positive.code:     inherit (stdenvAdapters) overrideCC;
    };
  
    llvmPackages_4 = callPackage ../development/compilers/llvm/4 ({
      inherit (stdenvAdapters) overrideCC;
    } // stdenv.lib.optionalAttrs stdenv.isDarwin {
      cmake = cmake.override { isBootstrap = true; };
      libxml2 = libxml2.override { pythonSupport = false; };
      python2 = callPackage ../development/interpreters/python/cpython/2.7/boot.nix { inherit (darwin) CF configd; };
    });
  
    llvmPackages_5 = callPackage ../development/compilers/llvm/5 {
      inherit (stdenvAdapters) overrideCC;
    };
  
    manticore = callPackage ../development/compilers/manticore { };
  
  
negative.code:   llvm_35 = llvmPackages_35.llvm;
    llvm_34 = llvmPackages_34.llvm;
  
    llvmPackages = recurseIntoAttrs llvmPackages_5;
  
    llvmPackagesSelf = llvmPackages_34.override {
      stdenv = libcxxStdenv;
  