-warn on error

git-svn-id: https://gnunet.org/svn/gnunet@34532 140774ce-b5e7-0310-ab8b-a85725594a96
-could be other peer's fault

git-svn-id: https://gnunet.org/svn/gnunet@34533 140774ce-b5e7-0310-ab8b-a85725594a96