Re: [boost] Re: shared_ptr and serialization

From: Peter Dimov (pdimov_at_[hidden])
Date: 2004-11-18 07:22:35

Peter Petrov wrote:
> Gennadiy Rozental <gennadiy.rozental <at> thomson.com> writes:
> 
>> Here we do very simple (or complex,depends on point of view) trick
>> instead of above
>> Let say we have somewhere map<T*,shared_ptr<T>*> registry;
>> 
>>     if( registry[raw_ptr] == 0 ) {
>>        t = shared_ptr<T>( raw_ptr )
>>        registry.add( raw_ptr, &t );
>>     }
>>     else
>>         t = *registry[raw_ptr];
>> 
>>>     // current shared_ptr implementation depends upon an internal
>>> pointer to a shared count.
>>> }
>> 
>> Do I miss something important?
> 
> What happens when some time after deserialization, one of the
> deserialized shared_ptr's is destroyed? Your "registry" has no way to
> know that and will still hold a shared_ptr referencing the same
> object, which is not correct.

The registry is not meant to outlive the deserialization process.