gistfile1.txt

kly@leia:~$ cat foo.c
#include <stdio.h>
int main(void) {
	float f = 340282346638528859811704183484516925440.000000;
	float x = f + 199999999999999999999.9F;
	printf ("%f vs %f (%s)\n",f,x, (f==x) ? "match" : "no match");
	return 0;
}
kly@leia:~$ gcc -Wall -g foo.c
kly@leia:~$ ./a.out 
340282346638528859811704183484516925440.000000 vs 340282346638528859811704183484516925440.000000 (match)
kly@leia:~$