`validation_flush_tests/getcoinscachesizestate` fails on RISCV-64 on master:
```
Running 394 test cases...
test/validation_flush_tests.cpp(99): error: in "validation_flush_tests/getcoinscachesizestate": check chainstate.GetCoinsCacheSizeState(tx_pool, MAX_COINS_CACHE_BYTES, 0) == CoinsCacheSizeState::OK has failed [1 != 0]

*** 1 failure is detected in the test module "Bitcoin Core Test Suite"
```
Haven't investigated why, yet. Apart from the architecture it could also be some dependency version causing the problem (this is a fedora rawhide install with very new versions of everything including gcc and boost).

Edit: see below, this is likely due to a newer `libstdc++`
}
            std::string transaction = test[1].get_str();
            CDataStream stream(ParseHex(transaction), SER_NETWORK, PROTOCOL_VERSION);
            CTransaction tx(deserialize, stream);
            TxValidationState state;
            BOOST_CHECK_MESSAGE(CheckTransaction(tx, state), strTest);
            BOOST_CHECK(state.IsValid());
            PrecomputedTransactionData txdata(tx);
            for (unsigned int i = 0; i < tx.vin.size(); i++)
            {
                if (!mapprevOutScriptPubKeys.count(tx.vin[i].prevout))
                {
                    BOOST_ERROR("Bad test: " << strTest);
                    break;
                }
                CAmount amount = 0;
                if (mapprevOutValues.count(tx.vin[i].prevout)) {
                    amount = mapprevOutValues[tx.vin[i].prevout];
                }
                unsigned int verify_flags = ParseScriptFlags(test[2].get_str());
                const CScriptWitness *witness = &tx.vin[i].scriptWitness;
                BOOST_CHECK_MESSAGE(VerifyScript(tx.vin[i].scriptSig, mapprevOutScriptPubKeys[tx.vin[i].prevout],
                                                 witness, verify_flags, TransactionSignatureChecker(&tx, i, amount, txdata), &err),
                                    strTest);
                BOOST_CHECK_MESSAGE(err == SCRIPT_ERR_OK, ScriptErrorString(err));
            }
        }
    }
}
BOOST_AUTO_TEST_CASE(tx_invalid)