#include <stdio.h> struct sss{ int i1:29; int i2:16; int i3:7; }; static union u{ struct sss sss; unsigned char a[sizeof (struct sss)]; } u; int main (void) { int i; for (i = 0; i < sizeof (struct sss); i++) u.a[i] = 0; u.sss.i1 = 536870911.0; for (i = 0; i < sizeof (struct sss); i++) printf ("%x ", u.a[i]); printf ("\n"); u.sss.i2 = 65535.0; for (i = 0; i < sizeof (struct sss); i++) printf ("%x ", u.a[i]); printf ("\n"); u.sss.i3 = 127.0; for (i = 0; i < sizeof (struct sss); i++) printf ("%x ", u.a[i]); printf ("\n"); return 0; }