Re: [Boost-bugs] [Boost C++ Libraries] #13148: Zero value cannot be converted from cpp_dec_float_50 to cpp_rational

Subject: Re: [Boost-bugs] [Boost C++ Libraries] #13148: Zero value cannot be converted from cpp_dec_float_50 to cpp_rational
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2017-08-15 17:08:13

#13148: Zero value cannot be converted from cpp_dec_float_50 to cpp_rational
------------------------------------+----------------------------
  Reporter:  Lev Sch <zorechfan@…>  |      Owner:  John Maddock
      Type:  Bugs                   |     Status:  new
 Milestone:  To Be Determined       |  Component:  multiprecision
   Version:  Boost 1.64.0           |   Severity:  Problem
Resolution:                         |   Keywords:
------------------------------------+----------------------------

Comment (by Jacob Garber <jgarber1@…>):

 Compiling with `-fsanitize=undefined` reveals an integer overflow:

 {{{
 /usr/local/include/boost/multiprecision/detail/generic_interconvert.hpp:433:22:
 runtime error: negation of -2147483648 cannot be represented in type
 'typename cpp_dec_float<50, int, void>::exponent_type' (aka 'int'); cast
 to an unsigned type to negate this value to itself
 }}}

 I can't reproduce with 1.63. It looks like this was introduced in the fix
 for #12625.

-- 
Ticket URL: <https://svn.boost.org/trac10/boost/ticket/13148#comment:1>
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