Re: [Boost-bugs] [Boost C++ Libraries] #12039: cpp_bin_float convert_to<double>() rounding mistake

Subject: Re: [Boost-bugs] [Boost C++ Libraries] #12039: cpp_bin_float convert_to<double>() rounding mistake
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2016-03-15 11:47:31

#12039: cpp_bin_float convert_to<double>() rounding mistake
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  Reporter:  Michael Shatz <shatz@…>  |      Owner:  johnmaddock
      Type:  Bugs                     |     Status:  closed
 Milestone:  To Be Determined         |  Component:  multiprecision
   Version:  Boost 1.61.0             |   Severity:  Problem
Resolution:  fixed                    |   Keywords:
--------------------------------------+----------------------------

Comment (by Michael Shatz <shatz@…>):

 Hi John

 There exists another more obscure but very similar problem: double
 rounding in conversion to 'float' due to initial conversion to 'double'.
 Practically, due to huge difference in precision between 'double' and
 'float', this problem is far less severe than the previous one. It is very
 unlikely that it negatively affect real-world applications. Still, when
 you know where to look, it can be easily demonstrated.

 May be, when you are at it, it makes sense to fix this minor problem as
 well?

 A test case (convert32_test.cpp) attached above.

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/12039#comment:3>
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