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.
{
public:
    std::string name;
    std::string purpose;
    CAddressBookData() : purpose("unknown") {}
    typedef std::map<std::string, std::string> StringMap;
    StringMap destdata;
};
struct CRecipient
{
    CScript scriptPubKey;
    CAmount nAmount;
    bool fSubtractFeeFromAmount;
};
typedef std::map<std::string, std::string> mapValue_t;
static inline void ReadOrderPos(int64_t& nOrderPos, mapValue_t& mapValue)
{
    if (!mapValue.count("n"))
    {
        nOrderPos = -1; 
        return;
    }
    nOrderPos = atoi64(mapValue["n"].c_str());
}
static inline void WriteOrderPos(const int64_t& nOrderPos, mapValue_t& mapValue)