You can drill a bunch of holes, lace the pieces together with safety wire, then cover the seam with silicone.
I read it in a book once.
I think I've seen a picture of it. I was surprised that it was an approved repair method.
Well if that's the case, then I could do that with my current rear window. It has two massive cracks forming a cross, but all the pieces are there. Would have to do something about the massive amount of crazing, though.
