Not quite sure what is going on here. I am serializing shared_ptr, that make use of derivation from enable_shared_from_this. However when my class is restored from disk, it appears that accessing shared_from_this() throws a tr1::bad_weak_ptr. Using boost 1.42, gcc 4.2.1, on suse linux. Has any one hit a similar issues, or found any work arounds ? Any help greatly appreciated. Here is some contrived standalone code, that demonstrate the problem. /////////1/////////2/////////3/////////4/////////5/////////6/////////7/////////8 // =========== file Main.cpp =================== // After restoring a class via shared_ptr it // appears as if enable_shared_from_this has not // been honoured. When accessing shared_from_this() // I get tr1::bad_weak_ptr exception. #include <iostream> #include <fstream> #include <assert.h> #include <boost/archive/text_iarchive.hpp> #include <boost/archive/text_oarchive.hpp> #include <boost/serialization/base_object.hpp> #include <boost/serialization/string.hpp> #include <boost/serialization/vector.hpp> #include <boost/serialization/shared_ptr.hpp> #include <boost/serialization/export.hpp> #include <boost/shared_ptr.hpp> #include <boost/enable_shared_from_this.hpp> using namespace std; using namespace boost; class Base : public boost::enable_shared_from_this<Base> , private boost::noncopyable { protected: Base() {} virtual ~Base() {} public: virtual const std::string& name() const = 0; private: friend class boost::serialization::access; template<class Archive> void serialize(Archive & ar, const unsigned int){} }; typedef boost::shared_ptr<Base> base_ptr; class Derived : public Base { public: Derived(const std::string& name ) : Base(), name_(name){} Derived() {} virtual ~Derived() {} virtual const std::string& name() const { return name_;} base_ptr find(const std::string& name) const { if (name_ == name) { Derived* nonConstThis = const_cast<Derived*>(this); return nonConstThis->shared_from_this(); // throws after restore ? } return base_ptr(); } private: std::string name_; friend class boost::serialization::access; template<class Archive> void serialize(Archive & ar, const unsigned int) { ar & boost::serialization::base_object<Base>(*this); ar & name_; } }; typedef boost::shared_ptr<Derived> d_ptr; class Holder { public: Holder() {} void add(d_ptr b) { vec_.push_back(b);} base_ptr find(const std::string& name) const { for(size_t i=0; i < vec_.size(); i++){ base_ptr base = vec_[i]->find(name); if (base) return base; } return base_ptr(); } private: std::vector<d_ptr> vec_; friend class boost::serialization::access; template<class Archive> void serialize(Archive & ar, const unsigned int){ ar & vec_; } }; void save(const Holder& holder, const char* filename) { std::ofstream ofs( filename ); boost::archive::text_oarchive oa( ofs ); oa << holder; } void restore(Holder& holder, const char* filename) { std::ifstream ifs( filename ); boost::archive::text_iarchive ia( ifs ); ia >> holder; } int main() { std::string fileName = "test.txt"; { Holder holder; holder.add( d_ptr(new Derived("me"))); holder.add( d_ptr(new Derived("you"))); base_ptr b = holder.find("me"); assert(b.get()); // works save(holder, fileName.c_str()); } Holder restored; restore(restored,fileName.c_str()); // why does the restored class throw // a weak ptr exception try { base_ptr b = restored.find("me"); // fails ? assert(b.get()); // never gets here } catch (std::exception& e) { std::cout << "Ooops exception " << e.what() << " thrown, test failed??? \n"; std::remove(fileName.c_str()); return 1; } std::remove(fileName.c_str()); cout << "test passed\n"; } Best regards, Ta, Avi