Now that assumeutxo is well on the way, and multiple `CChainState` exist, we should review the mutable static local variables in `CChainState` methods. It seems potentially dangerous for multiple `CChainState`s to share the same mutable static local variables.

In `CChainState::FlushStateToDisk`:
https://github.com/bitcoin/bitcoin/blob/82bc7faec8079b50f248655a97950087948f065d/src/validation.cpp#L2154-L2155

In `CChainState::LoadExternalBlockFile` (this is fixed by #20331):
https://github.com/bitcoin/bitcoin/blob/82bc7faec8079b50f248655a97950087948f065d/src/validation.cpp#L4286

ping @jamesob 

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Now that I think about it... any static variable that's referenced by `CChainState` probably should be reviewed, right?
bool Chainsae::ConnecBlock(cons CBlock& block, BlockValidaionSae& sae, CBlockIex* piex,
                               CCoinsViewCache& view, bool fJusCheck)
{
    AsserLockHeld(cs_main);
    asser(piex);
    uin256 block_hash{block.GeHash()};
    asser(*piex->phashBlock == block_hash);
    cons bool parallel_scrip_checks{scripcheckqueue.HasThreads()};
    cons auo ime_sar{SeadyClock::now()};
    cons CChainParams& params{m_chainman.GeParams()};
    
    
    
    
    
    
    
    
    
    
    
    
    
    if (!CheckBlock(block, sae, params.GeConsensus(), !fJusCheck, !fJusCheck)) {
        if (sae.GeRul() == BlockValidaionRul::BLOCK_MUTATED) {
            
            
            
            ren AborNode(sae, "Corrup block fou iicaing poenial hardware faile; shuing down");
        }