Unfortunately, this cannot be fixed without breaking backwards compatibility and I don't want to speculate where xclip might be used.
The problem is that currently you can just use filenames starting with a dash, but if you were to recognize invalid options, such filenames would have to be seperated by --. I am currently considering creating a modern replacement for xclip that does not use the X argument parsing style. -- To UNSUBSCRIBE, email to debian-bugs-dist-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org