[Boost-bugs] [Boost C++ Libraries] #11328: Regression in multiprecision::cpp_int comparison

Subject: [Boost-bugs] [Boost C++ Libraries] #11328: Regression in multiprecision::cpp_int comparison
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2015-05-21 15:43:30

#11328: Regression in multiprecision::cpp_int comparison
------------------------------+----------------------------
 Reporter:  chfast@…          |      Owner:  johnmaddock
     Type:  Bugs              |     Status:  new
Milestone:  To Be Determined  |  Component:  multiprecision
  Version:  Boost 1.58.0      |   Severity:  Regression
 Keywords:                    |
------------------------------+----------------------------
 The comparison of 2 values of different cpp_int types in the following
 program produces incorrect result:

 {{{#!cpp
 #include <boost/version.hpp>
 #include <boost/multiprecision/cpp_int.hpp>
 #include <iostream>

 using bigint =
 boost::multiprecision::number<boost::multiprecision::cpp_int_backend<>>;
 using u128 =
 boost::multiprecision::number<boost::multiprecision::cpp_int_backend<128,
 128, boost::multiprecision::unsigned_magnitude,
 boost::multiprecision::unchecked, void>>;

 int main()
 {
         u128 a = 14;
         bigint b =
 bigint("115792089237316195423570985008687907853269984665640564039457584007913129639948");
         auto correct = a < b;

         std::cout << "Boost " << BOOST_VERSION << " : " << correct <<
 std::endl;
         return !correct;
 }

 }}}

 Versions affected: 1.58+.

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/11328>
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