Search code examples
c++boost-serialization

Does Boost.Serialization Free the Memory Created during Loading Pointers?

To be specific, I'm referring to the demo in Boost.Serialization tutorial here.

In the above demo, bus_top instances are stored as pointers in bus_route to showcase how serialization of pointers is achieved. However, I observed an interesting behavior, that is, the destructor bus_stop::~bus_stop() is never invoked for the bus_stop objects created by restore_schedule(). I put a break point in bus_stop::~bus_stop() and it was triggered only by the delete statements at the end of main function.

During loading serialized data, objects to initialize pointers are allocated in pointer_iserializer defined in boost/archive/detail/iserializer.hpp, which uses a heap_allocator to allocate space.

They do have a destroy function to release allocated memory in boost/serialization/access.hpp, but seems never got invoked.

Is it correct that Boost.Serialization does not manage the pointers created during loading data?

Solution

  • Conclusions:

    • The pointers are stored during loading and the objects they point to are created by new (i.e. boost::archive::detail::heap_allocator, boost::serialization::access::construct)
    • There is also a boost::serialization::access::destroy, but AFAIK, it's not got invoked in boost anywhere.
    • It's the user's duty to free the objects allocated by boost::serialization, using delete (or boost::serialization::access::destroy if you like).