std::atomic_shared_ptr

[Mikhail Matrosov]

Hi, Thomas,

> It didn't make the cutoff for GCC11 stage1, I hope to get it into GCC12.

Glad to hear that!

> Also, to set expectations, it will not be a lock free atomic.

Hm. That's surprising. And honestly does not look very useful. We can
always wrap a shared_ptr in a mutex.

There exist lock-free implementations in the wild. E.g. in folly. Would it
be possible to adopt one of those?

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Best regards, Mikhail Matrosov