I don't know of many major bugs, but they've essentially ignored the ones that are just annoying, even the really blatant ones I reported back in version 2.2 and earlier, when XP was not required. Quartus often changes, in a minor way, signal names assigned to a bus. It's subsequently impossible to remove them from the list repeatedly presented in the pin assignment dialog, even though you delete the signal names. It's quite arbitrary about that, too, BTW, in that it may change the names of all the signals on one bus, but leave another quite untouched.

You'll get warnings for combinatorial loops, despite the fact that that, precisely, is how one builds latches with a single macrocell. You see you've gotten warnings indicating that you aren't using the tristate buffers in their library components if they happen to be tristate.

Most of their warnings are of that sort and shouldn't impact your work. They do increase the consumption of aspirin, Maalox (an antacid), whiskey, and prune juice. I don't like this tendency. Xilinx ISE, OTOH, often reports, as errors, conditions which you can't even locate. These often go away if you close and reopen the source file. Go figure!

Good luck!

RE