anchor.diff:  
     # This is to avoid self-references, which causes the initrd to explode
     # in size and in turn prevents mdraid systems from booting.
  -  allowedReferences = [ stdenv.cc.libc.out ];
  +  allowedReferences = [ stdenv.cc.libc.out sendmail-script ];
   
     patches = [ ./no-self-references.patch ];
   
  
positive.code:   preConfigure = ''
      sed -e 's@/lib/udev@''${out}/lib/udev@' \
          -e 's@ -Werror @ @' \
          -e 's@/usr/sbin/sendmail@/run/wrappers/bin/sendmail@' -i Makefile
    '';
  
    meta = {
  
negative.code: { stdenv, writeScript
  , fetchurl, groff
  , buildPlatform, hostPlatform
  }:
  
  assert stdenv.isLinux;
  
  let
    sendmail-script = writeScript "sendmail-script" ''
      #!/bin/sh
  
      if [ -x /run/wrappers/bin/sendmail ]; then
        /run/wrappers/bin/sendmail "$@"
      else
        /run/current-system/sw/bin/sendmail "$@"
      fi
    '';
  in
  stdenv.mkDerivation rec {
    name = "mdadm-4.0";
  
  