Will sending `kill -11` to Java process raises a NullPointerException?

Note that the question of "what layout does `siginfo_t` have here? (in particular, when to check the signal number vs the signal code)" is quite nontrivial. For the full answer, see the kernel's `siginfo_layout`. Note that there's an abominable case of the USB asyncio accessing the wrong member.

[1]: https://elixir.bootlin.com/linux/v6.9.7/source/kernel/signal...

This was fascinating. Do you have to be the same user or group to send the signal?

I'm absolutely positive the JVM is not the only thing using this trick, seems like it could be an attack vector.

more interesting explanation and benchmarks: https://shipilev.net/jvm/anatomy-quarks/25-implicit-null-che...

hotspot's always-on runtime profiling (and corresponding runtime dynamic optimization) is pretty neat.

Huh. I was going to say, no, of course not, it checks that you're actually accessing a null pointer, but where there's a will there's a way.