https://travis-ci.org/github/bitcoin/bitcoin/jobs/679885530#L8791
if (bnb_used) {
                            coin_selection_params.use_bnb = false;
                            continue;
                        }
                        else {
                            error = _("Insufficient funds");
                            return false;
                        }
                    }
                } else {
                    bnb_used = false;
                }
                const CAmount nChange = nValueIn - nValueToSelect;
                if (nChange > 0)
                {
                    
                    CTxOut newTxOut(nChange, scriptChange);
                    
                    
                    
                    if (IsDust(newTxOut, discard_rate) || bnb_used)
                    {
                        nChangePosInOut = -1;
                        nFeeRet += nChange;
                    }
                    else
                    {
                        if (nChangePosInOut == -1)
                        {