anonymous — Wed, 28 May 2008 20:22:34 GMT

We have the same problem. When an instance of ClassB is serialized, all the saved pointers in map are lost.

We are using Boost 1.35.0 running on Fedora7(64 bits). gcc version 4.1.2

#include <string> #include <map>

#include <boost/serialization/serialization.hpp> #include <boost/serialization/access.hpp> #include <boost/serialization/is_abstract.hpp>

#include <boost/serialization/base_object.hpp> #include <boost/serialization/extended_type_info_typeid.hpp> #include <boost/serialization/export.hpp>

#include <boost/serialization/string.hpp>

#include <boost/mpl/and.hpp> #include <boost/serialization/map.hpp>

using namespace std; using namespace boost::serialization;

class A {

friend class boost::serialization::access; template<class Archive> void serialize(Archive & ar, const unsigned int version) { };

}

class B : public A { private:

friend class boost::serialization::access; template<class Archive> void serialize(Archive & ar, const unsigned int version) {

serialize base class information ar & boost::serialization::base_object<A>(*this); ar & value; ar & classACollection;

}

protected:

long value; std::map<long, ClassA * > classACollection;

public:

A(); virtual ~A();

} BOOST_CLASS_EXPORT(B);

class classA { private:

friend class boost::serialization::access; template<class Archive> void serialize(Archive & ar, const unsigned int version) {

ar & values;

}

protected:

std::map <long, ClassB *> values;

public:

ClassA(); ClassA(ClassA &object); virtual ~ClassA();

}

class B {

private:

friend class boost::serialization::access; template<class Archive> void serialize(Archive & ar, const unsigned int version) {

ar & value;

}

protected:

string value;

public:

ClassB(); ClassB(ClassB &object); virtual ~ClassB();

}

status changed; resolution set

Robert Ramey — Sun, 08 Jun 2008 20:49:29 GMT

status new → closed
resolution → wontfix

After a lot of work, I managed to discover what the problem is.

The following case will fail when all three of the following are true:

a) object is untracked (map<>::value_type in your case

b) object contains something else that is tracked

c) The containing object is moved after being deserialized - load a map has to do.

In your case this can be address by adding:

namespace boost { \ namespace serialization { \ template<> \ struct tracking_level< std::map<std::size_t, dummy>::value_type > \ { \

typedef mpl::integral_c_tag tag; \ typedef mpl::int_< boost::serialization::track_always > type; \ BOOST_STATIC_CONSTANT( \

int, \ value = tracking_level::type::value \

); \

}; } }

I haven't found any general solution. I'll add a note to the documentation.

Robert Ramey

Boost C++ Libraries: Ticket #1942: Pointers to elements in a std::map are not serilaized correctly

status changed; resolution set