anchor.diff:  
     iproute2mac = callPackage ../os-specific/darwin/iproute2mac { };
   
  -  libobjc = apple-source-releases.objc4;
  +  libobjc = self.objc4;
   
     lsusb = callPackage ../os-specific/darwin/lsusb { };
   
  
positive.code: 
    # Must use pkgs.callPackage to avoid infinite recursion.
  
    apple-source-releases = pkgs.callPackage ../os-specific/darwin/apple-source-releases { } self;
  
    impure-cmds = pkgs.callPackage ../os-specific/darwin/impure-cmds { };
  
    apple_sdk = pkgs.callPackage ../os-specific/darwin/apple-sdk {
      inherit (buildPackages.darwin) print-reexports;
      inherit (self) darwin-stubs;
    };
  in
  
  impure-cmds // apple-source-releases // {
  
    inherit apple_sdk;
  
  
negative.code: 
    binutils-unwrapped = callPackage ../os-specific/darwin/binutils {
      inherit (pkgs) binutils-unwrapped;
      inherit (pkgs.llvmPackages) llvm clang-unwrapped;
    };
  
    binutils = pkgs.wrapBintoolsWith {
  