anchor.diff:    */
     makeLibraryPath = pkgs: makeSearchPath "lib"
       # try to guess the right output of each pkg
  -    (map (pkg: pkg.lib or (pkg.out or pkg)) pkgs);
  +    (map (pkg: if pkg.outputUnspecified or false then pkg.lib or (pkg.out or pkg) else pkg) pkgs);
   
     /* Construct a binary search path (such as $PATH) containing the
        binaries for a set of packages.
  
positive.code:        => "/root/bin:/usr/bin:/usr/local/bin"
    */
    makeBinPath = pkgs: makeSearchPath "bin"
      (map (pkg: pkg.bin or (pkg.out or pkg)) pkgs);
  
  
    /* Construct a perl search path (such as $PERL5LIB)
  
negative.code:        => "/nix/store/9rz8gxhzf8sw4kf2j2f1grr49w8zx5vj-openssl-1.0.1r-bin/bin:/nix/store/wwh7mhwh269sfjkm6k5665b5kgp7jrk2-zlib-1.2.8/bin"
    */
    makeSearchPathOutputs = subDir: outputs: pkgs:
      makeSearchPath subDir (map (pkg: if pkg.outputUnspecified or false then lib.tryAttrs (outputs ++ ["out"]) pkg else pkg) pkgs);
  
    /* Construct a library search path (such as RPATH) containing the
       libraries for a set of packages
  