262  *   block[l % N] += s[l] (with carry)
263  * finally add carry if any
268     unsigned int tmp, gcd, remainder, lcm, carry;  in n_fold()  local
291     /* last to first to be able to bring carry forward */  in n_fold()
292     carry = 0;  in n_fold()
311         /* add with carry to any value placed by previous passes */  in n_fold()
312         tmp += carry + block[b];  in n_fold()
314         /* save any carry that may be left */  in n_fold()
315         carry = tmp >> 8;  in n_fold()
318     /* if any carry is left at the end, add it through the number */  in n_fold()
319     for (b = blocksize - 1; b >= 0 && carry != 0; b--) {  in n_fold()
320         carry += block[b];  in n_fold()
321         block[b] = carry & 0xff;  in n_fold()
322         carry >>= 8;  in n_fold()