[Boost-bugs] [Boost C++ Libraries] #12798: Strange division evaluation for dynamically allocated `cpp_bin_float`

Subject: [Boost-bugs] [Boost C++ Libraries] #12798: Strange division evaluation for dynamically allocated `cpp_bin_float`
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2017-01-31 12:43:27

#12798: Strange division evaluation for dynamically allocated `cpp_bin_float`
-------------------------------------+----------------------------
 Reporter:  michel                   |      Owner:  johnmaddock
     Type:  Bugs                     |     Status:  new
Milestone:  To Be Determined         |  Component:  multiprecision
  Version:  Boost Development Trunk  |   Severity:  Problem
 Keywords:                           |
-------------------------------------+----------------------------
 With this code
 {{{
 #include <iostream>
 #include <boost/multiprecision/cpp_bin_float.hpp>

 using namespace boost::multiprecision;
 using Real = number<cpp_bin_float<10000, digit_base_10,
 std::allocator<void>>>;

 int main(int argc, char* argv[])
 {
     std::cout << 1 / Real(1.4) << std::endl;
     return 0;
 }
 }}}
 assertion fails as
 {{{
 Assertion failed:
 ((
     eval_msb(q)
     ==
     cpp_bin_float<Digits, DigitBase, Allocator, Exponent, MinE,
 MaxE>::bit_count - 1
 )),
 function eval_divide, file boost/multiprecision/cpp_bin_float.hpp, line
 1086.
 }}}
 or it prints `26699.6` when compiled with `NDEBUG`.
 If I change `Real(1.4)` to `Real(1)`, the program does not terminate.

 Tested on g++-5.4.

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/12798>
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