anchor.diff:      done
     '';
   
  +  postFixup = stdenv.lib.optionalString (buildPackages.groff != groff) ''
  +    # Check to make sure none of the outputs depend on build-time-only groff:
  +    for outName in $outputs; do
  +      out=''${!outName}
  +      echo "Checking $outName(=$out) for references to build-time groff..."
  +      if grep -r '${buildPackages.groff}' $out; then
  +        echo "Found an erroneous dependency on groff ^^^" >&2
  +        exit 1
  +      fi
  +    done
  +  '';
  +
     enableParallelBuilding = true;
   
     doCheck = true;
  
positive.code: { stdenv, fetchurl, pkgconfig, libpipeline, db, groff, makeWrapper }:
  
  stdenv.mkDerivation rec {
    name = "man-db-2.7.5";
  
negative.code:   outputs = [ "out" "doc" ];
    outputMan = "out"; # users will want `man man` to work
  
    nativeBuildInputs = [ pkgconfig makeWrapper groff ]
      ++ stdenv.lib.optionals doCheck checkInputs;
    buildInputs = [ libpipeline db groff ]; # (Yes, 'groff' is both native and build input)
    checkInputs = [ libiconv /* for 'iconv' binary */ ];
  
    postPatch = ''
      substituteInPlace src/man_db.conf.in \
  