e69ec8be55
In the file included with the bugreport, framerates were dropping from 60fps to 11fps for an armature with several lattices parented, and a 5fps drop everytime an object was parented to the armature. Upon (re-)inspection of the code, it became apparent that this was being caused by a block of code that would recalculate the parent (perhaps recursively) as it thought the parent state was for the wrong timestamp. However, the timestamps this was using was never really updated (except for a single place, which set it to a single fixed value to force recalculations to take place), which meant that this branch was run all the time. AFACT, this is a remnant from some of the old timeoffset stuff + pre-Depsgraph timestamping hacks that are no longer used/set.