anchor.diff:  
     setupHook = ./setup-hook.sh;
   
  -  doCheck = true;
  +  doCheck = !stdenv.isDarwin;
   
     # some network-related tests don't work, mostly probably due to our sandboxing
     testsToSkip = ''
  
positive.code:     dist/IO/t/{io_multihomed.t,io_sock.t} \
      t/porting/{maintainers.t,regen.t} \
      cpan/Socket/t/get{name,addr}info.t \
    '' + stdenv.lib.optionalString stdenv.isFreeBSD ''
      cpan/CPANPLUS/t/04_CPANPLUS-Module.t \
      cpan/CPANPLUS/t/20_CPANPLUS-Dist-MM.t \
    '' + " ";
  
    postPatch = ''
      for test in ${testsToSkip}; do
        echo "Removing test" $test
        rm "$test"
  
negative.code:       "-Dlocincpth=${libc}/include"
        "-Dloclibpth=${libc}/lib"
      ]
      ++ optional (stdenv ? glibc) "-Dusethreads";
  
    configureScript = "${stdenv.shell} ./Configure";
  
  