 #include <climits>    // For CHAR_BIT.
 #include <cmath>      // For `sqrt` and `abs`.
 
+#include <fenv.h>
 #include <stdint.h>   // For `intN_t`.
+
 #include "random.h"
 #include "timer.h"
 

template <typename T>
int find_significant_digit(T x)
{
  return -int(std::floor(std::log10(std::abs(x))));
}



int main(int argc, char** argv)
{
  feenableexcept(FE_DIVBYZERO);
  feenableexcept(FE_INVALID);
  feenableexcept(FE_OVERFLOW);

  command_line_processor clp(argc, argv);

  #if defined(HAVE_TBB)
