Well, that's a very good question. Like I said, IANAL. I thought the GNU web site would be a good place to start looking, but I only found this. It repeats my concept of too-small-to-be-copyrightable, with some additional information, but does not give any information as to where this is encoded in the law (but I doubt the GNU project would say it was OK if it were not encoded in law). It also mentions that bug reports of the sort that PM was worried about are ideas, not code, and thus copyright does not apply to them. (Patents might, but they're pretty clearly obvious, and more importantly, things are not automaticly patented per default the way that they are automaticly copyrighted.)
Googling from there has gotten me nowhere. Sorry.
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