#include <execinfo.h>
#include <fenv.h>
#include <signal.h>

#if defined(__APPLE__)
  #include <xmmintrin.h>
#endif

#include <limits>
#include <stdexcept>
#include <string>

// include my project macros before I see Boost Units
// this defines BOOST_SIGNALING_NAN
// comment this out to disable signaling nan
#include "project_macros.hpp"

// this includes quantity.hpp
// this only defines BOOST_SIGNALING_NAN_ENABLED if 
// this version of Boost Units quantity.hpp has support 
// for BOOST_SIGNALING_NAN 
#include "boost/units/quantity.hpp"
#include "boost/units/systems/si/acceleration.hpp"

using std::numeric_limits;
using std::runtime_error;
using std::string;

void nan_signal_handler(int) {
  void *array[100];
  size_t size = backtrace(array, 10);
  char **strings = backtrace_symbols(array, size);
  string s = "\nError: memory initialized to signaling NaN was accessed\n";
  for (size_t i=0; i<size; ++i) {
    s += strings[i];
    s += "\n";
  }
  free(strings);
  throw runtime_error(s);
}

int main(int argc, char* argv[]) {
  using boost::units::quantity;
  using namespace boost::units;

  // register signal handler
  _MM_SET_EXCEPTION_MASK(_MM_GET_EXCEPTION_MASK() & ~(_MM_MASK_INVALID));
  signal(SIGFPE, &nan_signal_handler);

  const double s_nan = numeric_limits<double>::signaling_NaN();

  typedef quantity<si::acceleration, double> acceleration_t;

  // this quantity has been initialized to signaling nan 
  // if BOOST_SIGNALING_NAN_ENABLED is defined
  acceleration_t a;

#if defined(BOOST_SIGNALING_NAN_ENABLED)
  // this will trigger the SIGFPE signal handler
  a *= 5;
#else
  // this will not trigger the SIGFPE signal handler
  a *= 5;
#endif

  return 0;
}