Is 64 bit ?

#include <stdio.h>

int main()
{
  unsigned int code = 0x80000001;
  unsigned int a, b, c, d;

  __asm__ volatile ("cpuid" : "=a"(a), "=b"(b), "=c"(c), "=d"(d) : "a"(code));
  if(d&(1<<29))
    puts("he 64 bit");
  else
    puts("nao he 64 bit");
 return (0);
}