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.
{
    std::vector<COutput> vCoins(vAvailableCoins);
    
    if (coinControl && coinControl->HasSelected() && !coinControl->fAllowOtherInputs)
    {
        for (const COutput& out : vCoins)
        {
            if (!out.fSpendable)
                 continue;
            nValueRet += out.tx->tx->vout[out.i].nValue;
            setCoinsRet.insert(CInputCoin(out.tx, out.i));
        }
        return (nValueRet >= nTargetValue);
    }
    
    std::set<CInputCoin> setPresetCoins;
    CAmount nValueFromPresetInputs = 0;
    std::vector<COutPoint> vPresetInputs;
    if (coinControl)
        coinControl->ListSelected(vPresetInputs);
    for (const COutPoint& outpoint : vPresetInputs)
    {
        std::map<uint256, CWalletTx>::const_iterator it = mapWallet.find(outpoint.hash);
        if (it != mapWallet.end())
        {
            const CWalletTx* pcoin = &it->second;
            
            if (pcoin->tx->vout.size() <= outpoint.n)
                return false;