anchor.diff:      "CONF_GCC_LINKER_OPTS_STAGE2=-fuse-ld=gold"
     ] ++ stdenv.lib.optionals (disableLargeAddressSpace) [
       "--disable-large-address-space"
  +  ] ++ stdenv.lib.optional enableDwarf [
  +    "--enable-dwarf-unwind"
  +    "--with-libdw-includes=${stdenv.lib.getDev elfutils}/include"
  +    "--with-libdw-libraries=${stdenv.lib.getLib elfutils}/lib"
     ];
   
     # Make sure we never relax`$PATH` and hooks support for compatability.
     strictDeps = true;
   
     nativeBuildInputs = [
  -    perl autoconf automake m4 python3 sphinx
  +    perl autoconf autoreconfHook automake m4 python3 sphinx
       ghc bootPkgs.alex bootPkgs.happy bootPkgs.hscolour
     ];
   
  
positive.code: 
  # build-tools
  , bootPkgs
  , autoconf, automake, coreutils, fetchgit, fetchpatch, perl, python3, m4, sphinx
  , bash
  
  , libiconv ? null, ncurses
  
  , useLLVM ? !stdenv.targetPlatform.isx86
  , # LLVM is conceptually a run-time-only depedendency, but for
  
negative.code:   outputs = [ "out" "doc" ];
  
    patches = [
    ];
  
    postPatch = "patchShebangs .";
  