Robert Ramey escribió:

I'm aware that some problems occur when loading a map of objects containing other objects whose types are tracked or something like that. I forget the details. The problem is that when an object is moved and that object contains other objects which are pointed to by other objects, I'm speaking from memory but may one can get the idea ffrom that.

I think we're talking about the same thing.

I am not entirely sure... Let me restate the issue just to be confident I'm getting it through. Consider this pseudocode: T t; ar>>t; v.push_back(t); // copy t somewhere else ar.reset_object_adress(&v.back(),&t); // and communicate it's been relocated This works fine and subsequents pointers to t, when loaded, will point to the its new location inside v. Now consider the variation: T* p; ar>>p; // *p is created and loaded automatically by Boost.Serialization v.push_back(*p); // copy *p somewhere else ar.reset_object_adress(&v.back(),p); // and communicate it's been relocated This does not seem to work: objects created automatically by Boost.Serialization when loaded through a pointer cannot be relocated with reset_object_address: subsequent pointers to this object will point to the same object as p, not to the element in v. Having a look at the source code of Boost.Serialization (basic_iarchive.cpp) it's apparent that moveable_objects_recent and moveable_objects_end are updated inside basic_iarchive::load_object, but are not inside basic_iarchive::load_pointer. Of course, I don't know what the hidden implications of updating these also in load_pointer could be, but I'd appreciate if you could comment on this. Joaquín M López Muñoz Telefónica, Investigación y Desarrollo

I looked into fixing this but I couldn't figure out how to do it. It might be possible to fix if one spent more time at it (or it might not). It's not trivial.

Robert Ramey

Joaquin M Lopez Munoz wrote:

...

Hello,

Consider a tracked type T which is only serialized through T pointers: under these circumnstances, when loading a T* Boost.Serialization automatically allocates a T object for the pointer to refer to. I've found out that these dynamically allocated objects cannot be moved by using reset_object_address: this member function simply ignores them.

Would it be possible that reset_object_address also took care of these objects or is there any limitation I'm not aware of? FWIW, this is not an academic question but has raised in connection with some serialization code I'm writing.

Thank you,

Joaquín M López Muñoz Telefónica, Investigación y Desarrollo

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Robert Ramey <ramey <at> rrsd.com> writes:

joaquin <at> tid.es wrote:

...

Having a look at the source code of Boost.Serialization (basic_iarchive.cpp) it's apparent that moveable_objects_recent and moveable_objects_end are updated inside basic_iarchive::load_object, but are not inside basic_iarchive::load_pointer. Of course, I don't know what the hidden implications of updating these also in load_pointer could be, but I'd appreciate if you could comment on this.

OK, I looked into this.

The list of tracked object that might be relocated as soon is the library is "done" with them.

line # 392 moveable_objects_recent = this_id;

That is when the stack is shortened. This keeps the list prety short. I would have to think about this some more.

Thank you! I'll also have a look myself and hopefully help a little.

I presume that in your case something like the following wouldn't help?

v.push_back(T()); ar >> v.back(); // assuming v.back() returns a reference

Unfortunately, no :-/ It is mandatory that I load Ts always through pointers. Joaquín M López Muñoz Telefónica, Investigación y Desarrollo