Made this issue a couple days ago, deemed invalid because it was "modded" with Optifine. So I removed it and booted Minecraft completely vanilla, no JVM arguments, and the crash happened sooner than previously reported, and more consistently.

Original bug: MC crashes every time I'm near blazes in the Nether Fortress. No amount of extra allocated RAM has remedied the problem.

I also can't attach a crash report as it doesn't create a file when the game crashes. But I've attached a picture of the game output at the time of the crash.