anchor.diff:                      QueuePid ! {skipped, Source},
                       compile_worker(QueuePid, Config, CompileFn);
                   Error ->
  -                    QueuePid ! {fail, [{error, Error},
  -                                       {source, Source}]},
  +                    QueuePid ! {fail, {{error, Error}, {source, Source}}},
                       ok
               end;
   
  
positive.code:                     compile_queue(Config, Pids, Rest)
              end;
  
          {fail, [_, {source, Source}}=Error] ->
              ?CONSOLE("Compiling ~s failed:\n",
                       [maybe_absname(Config, Source)]),
              maybe_report(Error),
  
negative.code:              end,
      format_errors(Config, Source, Prefix, Warnings).
  
  maybe_report({{error, {error, _Es, _Ws}=ErrorsAndWarnings}, {source, _}}) ->
      maybe_report(ErrorsAndWarnings);
  maybe_report([{error, E}, {source, S}]) ->
      report(["unexpected error compiling " ++ S, io_lib:fwrite("~n~p~n", [E])]);
  