Re: [Boost-bugs] [Boost C++ Libraries] #10740: Multi-level containers do not cooperate with address tracking

Subject: Re: [Boost-bugs] [Boost C++ Libraries] #10740: Multi-level containers do not cooperate with address tracking
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2014-11-27 18:19:57

#10740: Multi-level containers do not cooperate with address tracking
-------------------------------------+-------------------------------------
  Reporter:  Simon Etter             |      Owner:  ramey
  <ettersi@…>                        |     Status:  closed
      Type:  Bugs                    |  Component:  serialization
 Milestone:  To Be Determined        |   Severity:  Problem
   Version:  Boost 1.56.0            |   Keywords:  Address tracking, STL
Resolution:  invalid                 |  containers
-------------------------------------+-------------------------------------

Comment (by ramey):

 "To my understanding, Boost.Serialization wishes to maintain the invariant
 that if a pointer pointed to an object before the
 serialization/deserialization process, it also does so afterwards."

 nope.  loading an object serialized through a pointer creates a NEW
 pointer which is "equivalent" to the old one.  It's equivalent in that it
 points to a new and disjoint versions of the original.

 {{{
        // Again, we would like pd to point to the dummy object,
 independent
        // of where it is loaded. This is not the case, however.
        assert(&l.back().back() == pd); // Does fire!!!
 }}}

 Nope: we expect pd to point to some new object - disjoint but equivalent
 to the original one.

 {{{
         // Again, let pd point to the dummy object
         dummy* pd = &l.back().back();

         // Same as before...
         {
             std::ofstream ofs("two_level.xml");
             boost::archive::xml_oarchive oa(ofs);
             oa << BOOST_SERIALIZATION_NVP(l) <<
 BOOST_SERIALIZATION_NVP(pd);
         }
         dummy* pd1;
         {
             std::ifstream ifs("two_level.xml");
             boost::archive::xml_iarchive ia(ifs);
             ia >> BOOST_SERIALIZATION_NVP(l) >>
 BOOST_SERIALIZATION_NVP(pd1);
         }
         assert(*pd == *pd1); // should be true
 }}}

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/10740#comment:3>
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