struct timeval { int tv_sec; int tv_usec; }; extern struct timeval xtime; volatile struct timeval xtime __attribute__ ((aligned (16))); extern void printf(char *, ...); #define E(n) { printf("Error %d\n", n); return n; } int main() { if((int)&xtime & 0xF != 0) E(1); printf("Success\n"); return 0; }