> It's not exactly uncommon, it's basically C's equivalent to exceptions.

longjmp is very uncommon, I don't recall seeing any high-quality C codebase using it, and if you want exceptions, you should pick a different language because longjmp doesn't really give you comparable semantics. It's basically saying "ok, computer, f--k my s--t up".

The fact that OOM conditions are an enduring source of exploitable vulnerabilities in PHP really should give everyone a pause. Like, that's not a thing in any sane project.