Built against `master` branch 801dd40666d1e6009920ad3ff755c7bb993b2a62:

If I have no wallet.dat file and run:

    bitcoind -usehd=0

A new wallet.dat file is created and an HD seed is assigned.

I see an error message in the source:

    "Error loading %s: You can't disable HD on an already existing HD wallet or create new non-HD wallets."

but that doesn't get shown because `fFirstRun` is true, and so the code which checks for `-usehd` values doesn't run.

If it's no longer possible to create non-HD wallets, specifying -usehd=0 when creating a wallet should be an error, and not get silently ignored.
ShowProgress(_("Rescanning..."), 0); 
        double dProgressStart = GuessVerificationProgress(chainParams.TxData(), pindex);
        double dProgressTip = GuessVerificationProgress(chainParams.TxData(), chainActive.Tip());
        while (pindex && !fAbortRescan)
        {
            if (pindex->nHeight % 100 == 0 && dProgressTip - dProgressStart > 0.0)
                ShowProgress(_("Rescanning..."), std::max(1, std::min(99, (int)((GuessVerificationProgress(chainParams.TxData(), pindex) - dProgressStart) / (dProgressTip - dProgressStart) * 100))));
            if (GetTime() >= nNow + 60) {
                nNow = GetTime();
                LogPrintf("Still rescanning. At block %d. Progress=%f\n", pindex->nHeight, GuessVerificationProgress(chainParams.TxData(), pindex));
            }
            CBlock block;
            if (ReadBlockFromDisk(block, pindex, Params().GetConsensus())) {
                for (size_t posInBlock = 0; posInBlock < block.vtx.size(); ++posInBlock) {
                    AddToWalletIfInvolvingMe(block.vtx[posInBlock], pindex, posInBlock, fUpdate);
                }
            } else {
                ret = pindex;
            }
            pindex = chainActive.Next(pindex);
        }
        if (pindex && fAbortRescan) {
            LogPrintf("Rescan aborted at block %d. Progress=%f\n", pindex->nHeight, GuessVerificationProgress(chainParams.TxData(), pindex));
        }
        ShowProgress(_("Rescanning..."), 100); 
        fScanningWallet = false;
    }
    return ret;
}
void CWallet::ReacceptWalletTransactions()