No it would not be safe to use because under heat the crack could spread causing liquid to come in contact with the heating element and electrocute you.
No, it is not because the heat that surrounds the pot needs a smooth, uninterrupted surface on which to distribute. You risk explosion with continued use.
It's really not safe. Changes in temperature could cause it to break at the cracks. Also, bacteria is hard to clean out of the cracks, leading to food poisoning.
