anchor.diff:  
     jhc = callPackage ../development/compilers/jhc {
       inherit (haskellPackages_ghc6123) ghc binary zlib utf8String readline fgl
  -    regexCompat HsSyck random;
  +      regexCompat HsSyck random;
     };
   
     # Haskell and GHC
  
positive.code: 
    gnat = gnat45;
  
    gnat44 = wrapGCC (gcc44.gcc.override {
      name = "gnat";
      langCC = false;
      langC = true;
      langAda = true;
      profiledCompiler = false;
      inherit gnatboot;
      # We can't use the ppl stuff, because we would have
      # libstdc++ problems.
      cloogppl = null;
      ppl = null;
    });
  
    gnat45 = wrapGCC (gcc45.gcc.override {
      name = "gnat";
      langCC = false;
  
negative.code:       then gnu.libpthreadCross
        else null;
    }));
  
    gcc48_realCross = lib.addMetaAttrs { hydraPlatforms = []; }
      (callPackage ../development/compilers/gcc/4.8 {
  