anchor.diff:  {stdenv, fetchurl, readline, ghc, perl, m4, gmp, ncurses}:
   
   stdenv.mkDerivation (rec {
  -  name = "ghc-6.8.1";
  +  name = "ghc-6.8.2";
     homepage = "http://www.haskell.org/ghc";
   
     src = map fetchurl [
       { url = "${homepage}/dist/stable/dist/${name}-src.tar.bz2";
  -      md5 = "8d47d4dcde96c31fe8bedcee7f99eaf1";
  +      md5 = "745c6b7d4370610244419cbfec4b2f84";
       }
       { url = "${homepage}/dist/stable/dist/${name}-src-extralibs.tar.bz2";
  -      md5 = "f91de87e7c0a3fe2f27c5a83212d9743";
  +      md5 = "d199c50814188fb77355d41058b8613c";
       }
     ];
   
  
positive.code:     cat $setupHook    >> $out/nix-support/setup-hook
    ";
  
    patch64 = ./x86_64-linux_patch;
  
    # Thanks to Ian Lynagh ghc now works on x86_64-linux as well 
    patchPhase = if (stdenv.system == "x86_64-linux") then "patch -p2 < $patch64" else "";
  
    configureFlags="--with-gmp-libraries=${gmp}/lib --with-readline-libraries=${readline}/lib";
  
    preConfigure = "
      # the presence of this file makes Cabal cry for happy while generating makefiles ...
      rm libraries/haskell-src/Language/Haskell/Parser.ly
      # still requires a hack for ncurses
      sed -i \"s|^\\\(ld-options.*$\\\)|\\\1 -L${ncurses}/lib|\" libraries/readline/readline.buildinfo.in
    ";
  
negative.code:   setupHook = ./setup-hook.sh;
  
    meta = {
      description = "The Glasgow Haskell Compiler";
    };
  
    postInstall = "
  