[Boost-bugs] [Boost C++ Libraries] #4038: hash_value(float) collision

Subject: [Boost-bugs] [Boost C++ Libraries] #4038: hash_value(float) collision
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2010-03-24 00:49:21

#4038: hash_value(float) collision
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 Reporter:  dsharlet@…                  |       Owner:  danieljames
     Type:  Bugs                        |      Status:  new        
Milestone:  Boost 1.43.0                |   Component:  hash       
  Version:  Boost 1.41.0                |    Severity:  Problem    
 Keywords:  hash_value collision float  |  
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 the hash_value function for floats has at least one collision that is
 rather serious:

 std::size_t zero = boost::hash_value(0.0f);
 std::size_t half = boost::hash_value(0.5f);

 both of these have the same hash value. Why not just use reinterpret_cast
 <> for this hash function?

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Ticket URL: <https://svn.boost.org/trac/boost/ticket/4038>
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