[Boost-bugs] [Boost C++ Libraries] #6280: numeric_cast throws on exactly representable conversion

Subject: [Boost-bugs] [Boost C++ Libraries] #6280: numeric_cast throws on exactly representable conversion
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2011-12-16 21:53:37

#6280: numeric_cast throws on exactly representable conversion
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 Reporter:  Simeon Maxein <smaxein@…>               |       Owner:  dgregor
     Type:  Bugs                                    |      Status:  new    
Milestone:  To Be Determined                        |   Component:  numeric
  Version:  Boost 1.47.0                            |    Severity:  Problem
 Keywords:                                          |  
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 If a double or float representing the smallest possible value of int64_t
 is cast to int64_t using numeric_cast, an exception is thrown saying that
 a negative overflow has occured.

 I would expect the cast to work, since the value is exactly representable
 in the target type. Since the absolute value is a power of two, there
 should not be any error in the floating point representation.

 This is also reproducable in trunk, according to VeXocide. I found the
 problem in Boost 1.47.0 on Windows, using MinGW 4.5.2.

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Ticket URL: <https://svn.boost.org/trac/boost/ticket/6280>
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