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I'm just toying around with the smart pointers in the upcoming new c++ standard. However I fail to grasp the usage of the shared_from_this function. Here is what I have: #include <iostream> #include <memory> class CVerboseBornAndDie2 : public std::enable_shared_from_this<CVerboseBornAndDie2> { public: std::string m_Name; CVerboseBornAndDie2(std::string name) : m_Name(name) { std::cout << m_Name << " (" << this << ") is born!" << std::endl; } virtual ~CVerboseBornAndDie2() { std::cout << m_Name << " (" << this << ") is dying!" << std::endl; } }; int main(){ CVerboseBornAndDie2* vbad = new CVerboseBornAndDie2("foo"); std::shared_ptr<CVerboseBornAndDie2> p = vbad->shared_from_this(); } and it throws a std::bad_weak_ptr exception in the line std::shared_ptr<CVerboseBornAndDie2> p = vbad->shared_from_this(); if I instead do std::shared_ptr<CVerboseBornAndDie2> p(vbad); it works and I can afterwards do std::shared_ptr<CVerboseBornAndDie2> p2 = p.get()->shared_from_this(); so must the object belong to one shared_ptr before I can use shared_from_this? But how can I know this beforehand?

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