I was messing around in Creative mode with some Iron Golems (summoned with /summon command) and making them fight other mobs, and when I attacked some Pigmen to make them angry, the Golem started attacking them, but suddenly the game crashed. I tried the same thing again and the same thing happened.

I also noticed that the Golem AI seems rather glitchy at the moment, but that particular issue has already been reported it seems. It's possible that this crash is caused by the glitchy AI, but it's still worth reporting in case they're unrelated issues.