anchor.diff:  
   doterl_compile(Config, OutDir, MoreSources) ->
       FirstErls = rebar_config:get_list(Config, erl_first_files, []),
  -    ErlOpts = rebar_config:get(Config, erl_opts, []),
  +    ErlOpts = filter_defines(rebar_config:get(Config, erl_opts, []), []),
  +    ?DEBUG("erl_opts ~p~n",[ErlOpts]),
       %% Support the src_dirs option allowing multiple directories to
       %% contain erlang source. This might be used, for example, should eunit tests be
       %% separated from the core application source.
  
positive.code: 
              lists:foldl(F, 10, Trees)
      end.
  
negative.code:     case needs_compile(Source, Target, Hrls) of
          true ->
              Opts = [{i, "include"}, {outdir, filename:dirname(Target)}, report, return] ++
                  ErlOpts,
              case compile:file(Source, Opts) of
                  {ok, _, []} ->
                      ok;
  