id	summary	reporter	owner	description	type	status	milestone	component	version	severity	resolution	keywords	cc
12083	Rounding mode not restored when using save_state rounding struct on x64	Aaron Balog <abalog@…>	Douglas Gregor	"The rounding mode is not restored when using interval_lib's save_state rounding struct on x64 when an exception is thrown (Visual Studio 2013/2015).  This can have critical impact on applications.  All rounding will remain downward after catching the exception.  This bug does not occur in Win32.

We've also reported this issue to Microsoft: https://connect.microsoft.com/VisualStudio/Feedback/Details/2487437

Boost Repro:

#include <boost/numeric/interval.hpp>

void test_interval_number::test_boost_rounding()
{
   try
   {
      boost::numeric::interval<double>::traits_type::rounding rnd;
      rnd.downward();

      throw 1;
   }
   catch (...)
   {

   }

   unsigned int fpu_flags = 0;
   errno_t err;

   err = _controlfp_s(&fpu_flags, 0, 0);
   assert(err == 0);

   assert((fpu_flags & _MCW_RC) != _RC_DOWN);
}
"	Bugs	new	To Be Determined	numeric	Boost 1.60.0	Showstopper		interval numeric rounding