How to check is pointer pointing to valid Object (that was not queued free) in GDNative C++?

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:bust_in_silhouette: Asked By Robotex

I have a bots. Each bot has Area2D and saves all bots that entered it into sensory memory as raw pointers to Node, given as argument of signal processing function:

void _on_PerceptionArea_body_entered(Node * body) {

When some bot is died, it calls queue_free() for itself.

But then I get crash because I try to access pointer to deleted bot in sensory memory.

Is it possible to check is pointer still valid? Or maybe is there a way to convert that pointer to something that will protect me from crashing?