Output with current master:

```
bench_bitcoin: bench/coin_selection.cpp:53: void CoinSelection(benchmark::State&): Assertion `success' failed.
{
    utxo_pool.clear();
    CAmount target = 0;
    for (int i = 0; i < utxos; ++i) {
        target += (CAmount)1 << (utxos+i);
        add_coin((CAmount)1 << (utxos+i), 2*i, utxo_pool);
        add_coin(((CAmount)1 << (utxos+i)) + ((CAmount)1 << (utxos-1-i)), 2*i + 1, utxo_pool);
    }
    return target;
}
static void BnBExhaustion(benchmark::State& state)
{
    
    std::vector<OutputGroup> utxo_pool;
    CoinSet selection;
    CAmount value_ret = 0;
    CAmount not_input_fees = 0;
    while (state.KeepRunning()) {
        
        CAmount target = make_hard_case(17, utxo_pool);
        SelectCoinsBnB(utxo_pool, target, 0, selection, value_ret, not_input_fees); 
        
        utxo_pool.clear();
        selection.clear();
    }
}
BENCHMARK(CoinSelection, 650);
BENCHMARK(BnBExhaustion, 650);