#include <stdio.h>

#ifdef __NetBSD__

#include <ieeefp.h>

#else

#include <stdint.h>

#define	FP_PS	0
#define	FP_PRS	1
#define	FP_PD	2
#define	FP_PE	3

int
fpsetprec(int nprec)
{
	uint32_t ocw, ncw;
	int oprec;

	asm volatile("fnstcw %0" : "=m"(ocw));

	oprec = (ocw >> 8) & 3;
	ncw = (ocw & ~(uint32_t)(3 << 8)) | (uint32_t)((nprec & 3) << 8);

	asm volatile("fldcw %0" : : "m"(ncw));

	return oprec;
}

#endif

int
main(void)
{
	volatile double lo = 2.4608250784829636e-20;
	volatile double hi = 3.0026742508190853e+20;
	volatile double w, d;
	volatile size_t n = 100;

	fpsetprec(FP_PE);
	w = (hi - lo)/(n - 2);
	d = (n - 2)*w;
	printf("bad %.17e\n", hi - (n - 2)*w);
	printf("good %.17e\n", hi - d);

	fflush(stdout);
	return ferror(stdout);
}