One new idea is that the very first black holes did not form from dead stars at all; instead, they formed directly from the collapse of huge amounts of gas. (kavlifoundation.org)
Once these bodies were massive enough, they could have created a gravitational force that attracted huge amounts of gas to ultimately form a giant planet. (sciencedaily.com)
If that was the case, the massive star would have dumped huge amounts of gas onto its companion, becoming light enough to collapse into a neutron star rather than a black hole. (sciencemag.org)