anchor.diff:      %%       much slower.
       ok = rebar_file_utils:rm_rf("ebin/*.beam priv/mibs/*.bin"),
   
  -    YrlFiles = rebar_utils:find_files("src", "^.*\\.yrl\$"),
  +    YrlFiles = rebar_utils:find_files("src", "^.*\\.[x|y]rl\$"),
       rebar_file_utils:delete_each(
  -      [ binary_to_list(iolist_to_binary(re:replace(F, "\\.yrl$", ".erl")))
  +      [ binary_to_list(iolist_to_binary(re:replace(F, "\\.[x|y]rl$", ".erl")))
           || F <- YrlFiles  ]),
   
       %% Erlang compilation is recursive, so it's possible that we have a nested
  
positive.code:             ?FAIL
      end.
  
  -spec compile_yrl(Source::string(), Target::string(), Config::#config{}) -> 'ok'.
  compile_yrl(Source, Target, Config) ->
      case yrl_needs_compile(Source, Target) of
          true ->
              Opts = [{parserfile, Target}, {return, true}
                      |rebar_config:get(Config, yrl_opts, [])],
              case yecc:file(Source, Opts) of
                  {ok, _, []} ->
                      ok;
                  {ok, _, _Warnings} ->
  
negative.code: 
  -spec compile(Config::#config{}, AppFile::string()) -> 'ok'.
  compile(Config, _AppFile) ->
      rebar_base_compiler:run(Config,
                              rebar_config:get_list(Config, xrl_yrl_first_files, []),
                              "src", ".xrl", "src", ".erl",
                              fun compile_xrl_yrl/3),
      rebar_base_compiler:run(Config,
                              rebar_config:get_list(Config, xrl_yrl_first_files, []),
                              "src", ".yrl", "src", ".erl",
                              fun compile_xrl_yrl/3),
      doterl_compile(Config, "ebin"),
      rebar_base_compiler:run(Config, rebar_config:get_list(Config, mib_first_files, []),
                              "mibs", ".mib", "priv/mibs", ".bin",
  