Does `std::vector::push_back()` Copy Objects?

Does std::vector Copy Objects with push_back?

After conducting extensive investigations using Valgrind, it has been suggested that std::vector creates a copy of any object pushed back into the vector. Is this assertion accurate? Can a vector not maintain a reference or pointer to an object without copying it?

Answer:

Yes, std::vector<T>::push_back() indeed creates a copy of the supplied argument and adds it to the vector. If you intend to store pointers to objects within the vector, employ std::vector<whatever*> rather than std::vector<whatever>.

However, you must guarantee that the objects referenced by the pointers remain valid while the vector maintains a reference to them. Smart pointers based on the RAII idiom offer a solution to this problem.

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