`CompareModifiedEntry`, as used in

https://github.com/bitcoin/bitcoin/blob/3c098a8aa0780009c11b66b1a5d488a928629ebf/src/miner.h#L97-L112

will trigger a compile-time error in many `const` operations of index #1 of `indexed_modified_transaction_set` because `CompareModifiedEntry::operator()` is not `const`.

Most likely related to:

https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=224129
* that are included in blocks in the new chain, and then process the remaining
 * still-unconfirmed transactions at the end.
 */
struct txid_index {};
struct insertion_order {};
struct DisconnectedBlockTransactions {
    typedef boost::multi_index_container<
        CTransactionRef,
        boost::multi_index::indexed_by<
            
            boost::multi_index::hashed_unique<
                boost::multi_index::tag<txid_index>,
                mempoolentry_txid,
                SaltedTxidHasher
            >,
            
            boost::multi_index::sequenced<
                boost::multi_index::tag<insertion_order>
            >
        >
    > indexed_disconnected_transactions;
    
    
    
    
    
    
    
    
    ~DisconnectedBlockTransactions() { assert(queuedTx.empty()); }