anchor.diff:              }" /no-such-path \
             --replace "${stdenv.cc}" /no-such-path \
             --replace "$man" /no-such-path
  -      '' + stdenv.lib.optionalString crossCompiling
  +      '' + optionalString crossCompiling
         ''
           mkdir -p $dev/lib/perl5/cross_perl/${version}
           for dir in cnf/{stub,cpan}; do
  
positive.code:       ++ optionals stdenv.isDarwin [ ./cpp-precomp.patch ./sw_vers.patch ]
        ++ optional crossCompiling ./MakeMaker-cross.patch;
  
      postPatch = ''
        pwd="$(type -P pwd)"
        substituteInPlace dist/PathTools/Cwd.pm \
          --replace "/bin/pwd" "$pwd"
      '' + stdenv.lib.optionalString crossCompiling ''
        substituteInPlace cnf/configure_tool.sh --replace "cc -E -P" "cc -E"
      '';
  
      # Build a thread-safe Perl with a dynamic libperls.o.  We need the
  
negative.code:       ++ optional stdenv.isSunOS "-Dcc=gcc"
        ++ optional enableThreading "-Dusethreads";
  
      configureScript = optionalString (!crossCompiling) "${stdenv.shell} ./Configure";
  
      dontAddPrefix = !crossCompiling;
  
  