[boost] [serialization] multiple reg problem

From: Neal Becker (ndbecker2_at_[hidden])
Date: 2006-09-14 11:10:52

I noticed that if I use both BOOST_CLASS_EXPORT and register_type it causes
an error.  Here is an example:

#include <boost/archive/text_iarchive.hpp>
#include <boost/archive/text_oarchive.hpp>
#include <iostream>
#include <sstream>
#include <boost/serialization/extended_type_info_typeid.hpp>
#include <boost/serialization/base_object.hpp>
#include <boost/serialization/split_member.hpp>
#include <boost/serialization/nvp.hpp>

struct base {
  double min, max;
  base (double _min, double _max) : min (_min), max (_max) {}
  base(){}
  template<class Archive>
  inline void serialize (Archive &ar, const unsigned int) {
    ar & BOOST_SERIALIZATION_NVP(min);
    ar & BOOST_SERIALIZATION_NVP(max);
  }
  virtual int noop() = 0;
};

struct derived : public base {
  derived (double _min, double _max) : base (_min, _max) {}
  derived(){}

  template<class Archive>
  inline void serialize (Archive &ar, const unsigned int) {
    ar & BOOST_SERIALIZATION_BASE_OBJECT_NVP (base);
  }
  int noop() { return 1; }
};

#include <boost/serialization/export.hpp>
BOOST_CLASS_EXPORT (derived)

struct A {
  base* b;
  A (base* _b) : b (_b) {}
  A() {}

  template<class Archive>
  void save (Archive & ar, const unsigned int version) const {
    ar.register_type (static_cast<derived*>(NULL)); <<< comment/uncomment
this line
    std::cout << b->min << ' ' << b->max << '\n';
    ar << BOOST_SERIALIZATION_NVP(b);
  }

  template<class Archive>
  void load (Archive & ar, const unsigned int version) {
    base* b = NULL;
    ar >> BOOST_SERIALIZATION_NVP(b);
    std::cout << b->min << ' ' << b->max << '\n';
  }

  BOOST_SERIALIZATION_SPLIT_MEMBER()
};

int main() {
  
  derived* p = new derived (1,2);

  const A a (p);
  std::stringstream ss;
  boost::archive::text_oarchive oa (ss);
  oa << a;

  ss.seekg (0);
  //  std::cout << ss.str() << '\n';
  ss.seekg (0);
  boost::archive::text_iarchive ia (ss);
  A b;

  ia >> b;
}

If ar.register_type is there, you get unregistered exception.