It is not impossible that the number of knots is stored wrong in the file (for example, it will be 1 knot only). This change fixes bad memory allocation and bad memory access in such cases. It also fixes strict compiler warning which was mentioning that the allocation size is wrong), There isn't really the correct way of dealing with such situation, so simply fall back to Blender's knots calculation. Differential Revision: https://developer.blender.org/D7765