anchor.diff:                            {error, term()}.
   active_manifests({ok, RiakObject, Manifests}) -> 
       {ok, RiakObject, riak_cs_manifest_utils:active_manifests(Manifests)};
  -active_manifests({error, _}=Error) -> Error.
  +active_manifests({error, _}=Error) -> 
  +    Error.
   
   -spec clean_manifests([lfs_manifest()], pid()) -> [lfs_manifest()].
   clean_manifests(ActiveManifests, RiakcPid) ->
  
positive.code:                    RiakcPid :: pid()) ->
      [binary()] | {error, term()}.
  gc_manifests(Manifests, RiakObject, Bucket, Key, RiakcPid) ->
      catch lists:foldl(fun(M, UUIDs) -> 
                            gc_manifest(M, RiakObject, Bucket, Key, RiakcPid, UUIDs) 
                        end, [], Manifests).
  
  -spec gc_manifest(M :: lfs_manifest(),
                    RiakObject :: riakc_obj:riakc_obj(),
  
negative.code: check({ok, _}, Val) -> 
      Val;
  check({error, _}=Error, _Val) -> 
      Error.
  
  %% @private
  -spec gc_specific_manifests(UUIDsToMark :: [binary()],
  