Re: [Boost-bugs] [Boost C++ Libraries] #5216: boost::hash<boost::shared_ptr<T>> Returns Only Two Values

Subject: Re: [Boost-bugs] [Boost C++ Libraries] #5216: boost::hash<boost::shared_ptr<T>> Returns Only Two Values
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2011-02-23 12:04:30

#5216: boost::hash<boost::shared_ptr<T>> Returns Only Two Values
---------------------------------------------------+------------------------
  Reporter:  Rob Stewart <robert.stewart@…>        |       Owner:  pdimov         
      Type:  Bugs                                  |      Status:  new            
 Milestone:  To Be Determined                      |   Component:  smart_ptr      
   Version:  Boost 1.44.0                          |    Severity:  Problem        
Resolution:                                        |    Keywords:  shared_ptr hash
---------------------------------------------------+------------------------

Comment (by Rob Stewart <robert.stewart@…>):

 Defining BOOST_HASH_NO_IMPLICIT_CASTS produces a static assertion failure
 which is better than the silent misbehavior.

 The following makes things work, regardless of whether
 BOOST_HASH_NO_IMPLICIT_CASTS is defined:

 {{{
 namespace boost
 {
    template <class T>
    std::size_t
    hash_value(boost::shared_ptr<T> const & _ptr)
    {
       return boost::hash_value(_ptr.get());
    }
 }
 }}}

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/5216#comment:1>
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