`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++`
{
    FillableSigningProvider keystore;
    CCoinsView coinsDummy;
    CCoinsViewCache coins(&coinsDummy);
    std::vector<CMutableTransaction> dummyTransactions = SetupDummyInputs(keystore, coins);
    CMutableTransaction t1;
    t1.vin.resize(3);
    t1.vin[0].prevout.hash = dummyTransactions[0].GetHash();
    t1.vin[0].prevout.n = 1;
    t1.vin[0].scriptSig << std::vector<unsigned char>(65, 0);
    t1.vin[1].prevout.hash = dummyTransactions[1].GetHash();
    t1.vin[1].prevout.n = 0;
    t1.vin[1].scriptSig << std::vector<unsigned char>(65, 0) << std::vector<unsigned char>(33, 4);
    t1.vin[2].prevout.hash = dummyTransactions[1].GetHash();
    t1.vin[2].prevout.n = 1;
    t1.vin[2].scriptSig << std::vector<unsigned char>(65, 0) << std::vector<unsigned char>(33, 4);
    t1.vout.resize(2);
    t1.vout[0].nValue = 90*CENT;
    t1.vout[0].scriptPubKey << OP_1;
    BOOST_CHECK(AreInputsStandard(CTransaction(t1), coins));
    BOOST_CHECK_EQUAL(coins.GetValueIn(CTransaction(t1)), (50+21+22)*CENT);
}
static void CreateCreditAndSpend(const FillableSigningProvider& keystore, const CScript& outscript, CTransactionRef& output, CMutableTransaction& input, bool success = true)
{
    CMutableTransaction outputm;
    outputm.nVersion = 1;
    outputm.vin.resize(1);
    outputm.vin[0].prevout.SetNull();
    outputm.vin[0].scriptSig = CScript();