9ce8dfaf6a
Curve parent requires valid path to exist for curve. If the path is disabled in the curve settings, displist evaluation will check the dependency graph whether the path is needed for parenting. The issue was that changing relations in the scene chagned need of the curve path but nothing tagged the curve to update it's path. For now use direct call of DAG_id_tag_update from set_parent(). In the bright future we might detect such a need in flush automatically in the depsgraph.