The standard seems not mention the thread-safety info on shared_from_this. However, cpppreference state :

> Effectively executes std::shared_ptr(weak_this), where weak_this is the private mutable std::weak_ptr member of enable_shared_from_this.

Can I take it as a guarantee that it's safe to call shared_from_this in multiple threads? Since if I understand correctly, constructing a shared_ptr with a shared_ptr or weak_ptr object, is thread safe.

Take the following code as an example:

class A : public std::enable_shared_from_this<A> {
public:
    std::shared_ptr<A> clone() {
        return shared_from_this();
    }
};

In this case, can I call A::clone() in multiple threads?

Regards