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.
{
    if (fChangeCached)
        return nChangeCached;
    nChangeCached = pwallet->GetChange(*this);
    fChangeCached = true;
    return nChangeCached;
}
bool CWalletTx::InMempool() const
{
    LOCK(mempool.cs);
    return mempool.exists(GetHash());
}
bool CWalletTx::IsTrusted() const