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.
{
        return (GetDebit(filter) > 0);
    }
    
    bool IsEquivalentTo(const CWalletTx& tx) const;
    bool InMempool() const;
    bool IsTrusted() const;
    int64_t GetTxTime() const;
    int GetRequestCount() const;
    
    bool RelayWalletTransaction(CConnman* connman);
    std::set<uint256> GetConflicts() const;
};
class CInputCoin {
public:
    CInputCoin(const CWalletTx* walletTx, unsigned int i)
    {
        if (!walletTx)
            throw std::invalid_argument("walletTx should not be null");
        if (i >= walletTx->tx->vout.size())
            throw std::out_of_range("The output index is out of range");
        outpoint = COutPoint(walletTx->GetHash(), i);
        txout = walletTx->tx->vout[i];
    }
    COutPoint outpoint;
    CTxOut txout;
    bool operator<(const CInputCoin& rhs) const {
        return outpoint < rhs.outpoint;
    }
    bool operator!=(const CInputCoin& rhs) const {