[boost] [shared_ptr] aliasing constructor mischief

From: Frank Mori Hess (frank.hess_at_[hidden])
Date: 2008-04-29 09:02:38

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I've noticed it is possible to construct a half-empty shared_ptr that has an 
empty shared_count but a non-null pointer (brief example program attached).  
Perhaps the aliasing constructor, and similarly the shared_count constructor 
should do some argument checking?

- -- 
Frank
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#include <boost/shared_ptr.hpp>
#include <iostream>

int main()
{
        boost::shared_ptr<int> empty;
        int x = 1;
        boost::shared_ptr<int> aliased(empty, &x);
        std::cout << "aliased use_count = " << aliased.use_count() << std::endl;
        std::cout << "aliased get = " << aliased.get() << std::endl;
        std::cout << "aliased dereference = " << *aliased << std::endl;

        return 0;
}

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