std::atomic_shared_ptr

[Mikhail Matrosov]

> Probably not, because it would require ABI-breaking changes to
std::shared_ptr, which is out of the question.

Could you please elaborate on that? I can see how folly uses
std::shared_ptr directly:

https://github.com/facebook/folly/blob/master/folly/concurrency/AtomicSharedPtr.h#L76
https://github.com/facebook/folly/blob/master/folly/concurrency/detail/AtomicSharedPtr-detail.h#L45

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Best regards, Mikhail Matrosov