3:00:45stassats`after (sb-int:set-floating-point-modes :rounding-mode :zero) (ftruncate 942847873023899d0 389.0908182309674d0) i get 2.423207716158d12 389.125d0
3:18:27stassats`i suppose truncate shouldn't really just use /, as it rounds to nearest
3:29:07stassats`changing rounding modes is not a good idea, so I suppose just check if the remainder changes its sign? but that means recomputing it, not great