Log functions referring to an entity in the symbol table. Is that possible?

You have a va开发者_JAVA百科riable:

$a = 0;

And this variable is passed by reference like crazy.

How do you log or gain all functions and methods that have been working on this variable?

---

You can use xdebug to do reference counting (http://php.net/manual/en/features.gc.refcounting-basics.php) but I don't think there is a way to determine where those references were created. I think you'd have to write your own PHP module to get that information.