anchor.diff:        ];
       sha256 = "039agw5rqvqny92cpkrfn243x2gd4xn13hs3xi6isk55d2vqqr9n";
     };
  -
  -  postPatch = stdenv.lib.optionalString stdenv.isDarwin ''
  -    substituteInPlace configure \
  -      --replace '/usr/bin/libtool' 'ar' \
  -      --replace 'AR="libtool"' 'AR="ar"' \
  -      --replace 'ARFLAGS="-o"' 'ARFLAGS="-r"'
  -  '';
   
     configureFlags = [
       (if static then "--static" else "")
  
positive.code: 
  let version = "1.2.8"; in
  
  stdenv.mkDerivation (rec {
    name = "zlib-${version}";
  
    src = fetchurl {
  
negative.code: 
    # As zlib takes part in the stdenv building, we don't want references
    # to the bootstrap-tools libgcc (as uses to happen on arm/mips)
    NIX_CFLAGS_COMPILE = [ "-fPIC" "-static-libgcc" ];
  
    crossAttrs = {
      dontStrip = static;
    };
  
    passthru.version = version;
  
  