13 Feb 2019 Introduction This is a write-up of the “behavioral analysis” of shared_ptr<T> reference count in GNU’s libstdc++. This smart pointer is used to share references to the same underlaying pointer. The mechanism beneath works by tracking the amount of references through a reference count so the pointer gets freed only after the last reference is destructed. It is usually used in multi-threaded programs (in conjunction with other types) because of the guarantees of having its reference co...