anchor.diff:  
     src =  fetchurl {
       url = "ftp://ftp.freedesktop.org/pub/mesa/${version}/MesaLib-${version}.tar.bz2";
  -    sha256 = "1w3bxclgwl2hwyxk3za7dbdakb8jsya7afck35cz0v8pxppvjsml";
  +    sha256 = "0w1jh8pl4gbzazigsqc5pzc076gckb7b9xgw2w633jlrjn7qdprw";
     };
   
     prePatch = "patchShebangs .";
   
  -  patches = [
  +  patches = [ # some don't apply -- try without them ATM
       ./static-gallium.patch
  -    ./dricore-gallium.patch
  -    ./werror-wundef.patch
  +   # ./dricore-gallium.patch
  +   # ./werror-wundef.patch
     ];
   
     # Change the search path for EGL drivers from $drivers/* to driverLink
  
positive.code:   '';
  
    outputs = ["out" "drivers" "osmesa"];
  
    preConfigure = "./autogen.sh";
  
    configureFlags = [
      "--with-dri-driverdir=$(drivers)/lib/dri"
  
negative.code: { stdenv, fetchurl, pkgconfig, intltool, flex, bison, autoreconfHook
  , python, libxml2Python, file, expat, makedepend
  , libdrm, xorg, wayland, udev, llvm, libffi
  , libvdpau, libelf
  , enableTextureFloats ? false # Texture floats are patented, see docs/patents.txt
  , enableExtraFeatures ? false # not maintained
  }:
  
  