Thanks. I suspected as much for LuaJIT because, like a JavaScript engine, it supports JIT compilation of untrusted code. It's interesting to hear that PUC Lua also needs these mitigations even though it's only an interpreter.
As for implementations of Python and Ruby, they might not worry about these attacks - because AFAIK they do not try to support secure execution of untrusted code.
Yes.
> What about the JVM and Microsoft's CLR?
Yes.