Convert shared_ptr

This question already has an answer here:

• Is there a way to cast shared_ptr<void> to shared_ptr<T>? 2 answers

Consider the following C++ code:

    template<class T>
    std::shared_ptr<void> eraseType(std::shared_ptr<T> p) {
        return p;
    }

    template<class T>
    std::shared_ptr<T> castType(std::shared_ptr<void> p) {
        return p;
    }

    int main()
    {
        auto p = eraseType(std::make_shared<int>(42));
        auto x = castType<int>(p); <-- does not compile
    }

eraseType is used to remove the type T from shared_ptr<T> in order to handle it in a generic way.

Of course, the code fails to compile since caseType is malformed.

Is there a way to create a narrowed shared_ptr<T> from a shared_ptr<void> assuming that we know that the shared_ptr holds a proper T?