anchor.diff:                                                                   absolute_path_from(State, FromFile),
                                                                    absolute_path_to(State, Release, ToFile))
                                             end)
  -                   end).
  +                   end);
  +do_individual_overlay(_State, _Release, _Files, _OverlayVars, Invalid) ->
  +    ?RLX_ERROR({malformed_overlay, Invalid}).
   
   -spec wildcard_copy(rlx_state:t(), rlx_release:t(), file:filename_all(), file:filename_all(),
         fun((file:filename_all(), file:filename_all()) -> ok | {error, term()}),
  
positive.code:                   [FromFile, [format_errors(F, Es) || {F, Es} <- Reason]]);
  format_error({unable_to_make_dir, Absolute, Error}) ->
      io_lib:format("Unable to make directory ~s because ~p",
                    [Absolute, Error]).
  
  %%%===================================================================
  %%% Internal Functions
  
negative.code:             erlang:error(?RLX_ERROR(Reason));
          OverlayVars ->
              Files = rlx_util:template_files(),
              case do_overlay(State, Release, Files, OverlayVars) of
                  {error, _} = E -> erlang:error(E);
                  {ok, State1} -> {ok, State1}
              end
      end.
  
  -spec format_error(ErrorDetail::term()) -> iolist().
  