redeclare nChainTx to use uint64_t #29331

Following up on #29258 the type of nChainTx has now been changed to a uint64_t allowing for the counting of TXs well into the future. The note about changing the type in 2024 was also removed. This passes all extended tests.

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Conflicts

Reviewers, this pull request conflicts with the following ones:

• #29370 (assumeutxo: Get rid of faked nTx and nChainTx values by ryanofsky)
• #28608 (assumeutxo state and locking cleanup by ryanofsky)

If you consider this pull request important, please also help to review the conflicting pull requests. Ideally, start with the one that should be merged first.

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_{Debug: https://github.com/bitcoin/bitcoin/runs/20917625235}

Would you mind adding a test? It should be possible to fake a large nChainTx in a test using assume utxo

It should be possible to fake a large nChainTx in a test using assume utxo

It's annoying that each test doing something like that would need to add an entry to the regtest chainparams, maybe my suggestion here to allow that per RPC could make sense (not necessarily in this PR).

It's annoying that each test doing something like that would need to add an entry to the regtest chainparams, maybe my suggestion #29261 (comment) to allow that per RPC could make sense (not necessarily in this PR).

I was thinking of a unit test, so no need for an RPC but yes some way to add assumeutxo data for tests would be needed (I assumed we already have this).

The note about changing the type in 2024 was also removed. This passes all extended tests.

I don't think you need to detail what is changed and if the tests pass in the description. It would be better to focus on information that is useful to reviewers. For example, a measurement of memory before and after.

Also, when changing the type, you'll have to check all places where this is used, and update them, if needed. For example, casts should be removed and other types need to be increased in width to hold the new values.

Are you still working on this? If not, I am happy to pick up.

Could I please have just a bit more time to work on this?

Thanks, Reese

@russeree are you still following up here?

@russeree are you still following up here?

I would be willing to hand this off now, primary issue is the inability to allocate the proper amount of time due to other work commitments.

Sorry if this caused any substantial setbacks.

No worries. @maflcko may pick it up.