mpz_init_setbit

[marco.bodrato at tutanota.com]

Ciao,

I think it would be useful  to have yet another mpz_init_ function, do you mind if I add it?
void
mpz_init_setbit (mpz_ptr dest, mp_bitcnt_t bit_idx)
{
  mp_ptr dp;
  mp_size_t limb_idx = bit_idx / GMP_NUMB_BITS;
  mp_limb_t mask = CNST_LIMB(1) << (bit_idx % GMP_NUMB_BITS);

  ALLOC (dest) = SIZ (dest) = limb_idx + 1;
  PTR (dest) = dp = __GMP_ALLOCATE_FUNC_LIMBS (limb_idx + 1);
  MPN_ZERO (dp, limb_idx);
  dp[limb_idx] = mask;
}

Ĝis,
mb