https://github.com/bitcoin/bitcoin/blob/9ad6f14175c19b5d47267c3dd5840c14bad43c83/src/validation.cpp#L3711

If i'm following right the flow of the code, when we hit this lane `pindex` should be always equal to nullptr thus this check may be omitted
AssertLockNotHeld(cs_main);
    
    
    
    
    LOCK(m_cs_chainstate);
    CBlockIndex *pindexMostWork = nullptr;
    CBlockIndex *pindexNewTip = nullptr;
    int nStopAtHeight = gArgs.GetArg("-stopatheight", DEFAULT_STOPATHEIGHT);
    do {
        
        
        
        
        
        
        LimitValidationInterfaceQueue();
        {
            LOCK(cs_main);
            LOCK(m_mempool.cs); 
            CBlockIndex* starting_tip = m_chain.Tip();