This matrix was used to store the space the object is in, which then was accessed by snapping code. No reason to keep it as a global variable (which isn't safe for threading, unlikely it'll give issues now, but it's easy to avoid issues early here). Now made it so BKE_object_where_is_calc_ex will get an optional parameter originmat and set this matrix in solve_parent. Original patch by self, minor changes by Campbell, thanks!