text: #include <math.h>
  
  #define EPS DBL_EPSILON
  static const double_t toint = 1/EPS;
  
  static double __round(double x)
  {
  	union {double f; uint64_t i;} u = {x};
  	int e = u.i >> 52 & 0x7ff;
  	double_t y;
  
  	if (e >= 0x3ff+52)
  		return x;
  	if (u.i >> 63)
  		x = -x;
  	if (e < 0x3ff-1) {
  		/* raise inexact if x!=0 */
  		FORCE_EVAL(x + toint);
  		return 0*u.f;
  	}
  	y = x + toint - toint - x;
  	if (y > 0.5)
  		y = y + x - 1;
  	else if (y <= -0.5)
  		y = y + x + 1;
  	else
  		y = y + x;
  	if (u.i >> 63)
  		y = -y;
  	return y;
  }
  
  extern __typeof(__round) round __attribute__((weak, alias("__round")));
  EXPORT_SYMBOL(round);
  