Re: [Boost-bugs] [Boost C++ Libraries] #3604: Access violation on diamond inheritance

Subject: Re: [Boost-bugs] [Boost C++ Libraries] #3604: Access violation on diamond inheritance
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2010-04-03 05:46:34

#3604: Access violation on diamond inheritance
----------------------------------+-----------------------------------------
  Reporter:  kondo@…              |       Owner:  ramey         
      Type:  Support Requests     |      Status:  reopened      
 Milestone:  Boost 1.41.0         |   Component:  serialization 
   Version:  Boost 1.40.0         |    Severity:  Not Applicable
Resolution:                       |    Keywords:                
----------------------------------+-----------------------------------------

Comment(by kondo@…):

 Thanks for reply.
 I checked your modification. It is surely based on my idea.
 And My test failed.

 I think there are some problems in your modification.
 Consider the case of cls1.png, abc1.cpp, cls2.png and abc2.cpp
 (attached.file).

 The new shortcut element of void_caster_registry is made by already
 registered member and current registering member.

 And if either includes virtual base, it shall include virtual base.

 {{{
 110    void_caster_shortcut(
 111        extended_type_info const * derived,
 112        extended_type_info const * base,
 113        std::ptrdiff_t difference,
 114        bool includes_virtual_base,
 115        void_caster const * const parent
 116    ) :
 117        void_caster(derived, base, difference, parent),
 118        m_includes_virtual_base(includes_virtual_base)
 119    {
 120        recursive_register(includes_virtual_base);
 121    }
 }}}

 I think the member function recursive_register() needs the argument
 includes_virtual_base.

 And in the member function recursive_register(), 'logical OR' operation is
 needed.

 {{{
 243        if(* m_derived == * (*it)->m_base){
 244            const void_caster_argument vca(
 245                (*it)->m_derived,
 246                m_base
 247            );
 248            void_cast_detail::set_type::const_iterator i;
 249            i = s.find(& vca);
 250            if(i == s.end()){
 251                new void_caster_shortcut(
 252                    (*it)->m_derived,
 253                    m_base,
 254                    m_difference + (*it)->m_difference,
 255                    (*it)->has_virtual_base() || includes_virtual_base,
 256                    this
 257                );
 258            }
 259        }
 260        if(* (*it)->m_derived == * m_base){
 261            const void_caster_argument vca(
 262                m_derived,
 263                (*it)->m_base
 264            );
 265            void_cast_detail::set_type::const_iterator i;
 266            i = s.find(& vca);
 267            if(i == s.end()){
 268                new void_caster_shortcut(
 269                    m_derived,
 270                    (*it)->m_base,
 271                    m_difference + (*it)->m_difference,
 272                    (*it)->has_virtual_base() || includes_virtual_base,
 273                    this
 274                );
 275            }
 276        }
 }}}

 Based on this idea, I modified the void_caster.cpp you attached.

 It is void_cast_add_or.cpp (attached file).

 After this modification, my test succeeded.

 What do you think?

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/3604#comment:11>
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