bitcoin/bips
1
0
Fork 0
mirror of https://github.com/bitcoin/bips.git synced 2026-04-20 16:28:39 +00:00
Code Issues Releases Wiki Activity

bip54: expand on rationale for non-final coinbase nSequence

Browse Source 
Making sure that the coinbase is timelocked is a neat simplification in reasoning about duplicates,
but it has caused some confusions. For instance here:
https://gnusha.org/pi/bitcoindev/e758af9b-72fc-4fdd-8e07-e1126635780an@googlegroups.com/

Fix this by explicitly stating the implications.
This commit is contained in:
Antoine Poinsot
2026-03-13 14:21:41 -04:00
parent aef4d9e084
commit 1f21139957
1 changed files with 9 additions and 1 deletions
Download Patch File Download Diff File Expand all files Collapse all files

10
bip-0054.md
View File

@@ -123,7 +123,10 @@ validation will need to be re-activated from block 1,983,702. A simple way to pr
mandate that future coinbase transactions vary from coinbase transactions before [bip-0034][BIP34]
activation. There are multiple ways of achieving this, but setting and enforcing the timelock for
the coinbase transaction makes it so all coinbase transactions past Consensus Cleanup activation
could not have been valid before this height and therefore cannot be a duplicate[^11].
could not have been valid before this height and therefore cannot be a duplicate[^11]. This
simplifies both reasoning and client implementation, since the [bip-0030][BIP30] check can be
skipped entirely past Consensus Cleanup activation, regardless of the [bip-0034][BIP34] activation
status[^12].
## Backward compatibility
@@ -218,6 +221,10 @@ bip-0034 height commitment and the corresponding future block height.
coinbase transactions as not having duplicate past Consensus Cleanup activation would be consistent
for any implementation which enforces `nLockTime` from the genesis block, which is the behaviour
notably of Bitcoin Core but also of all other implementations the authors are aware of.
[^12]: For instance Bitcoin Core only disables [bip-0030][BIP30] validation for a specific chain
where [bip-0034][BIP34] violations have been manually inspected (see [here][Core validation.cpp
BIP34]). Without the guarantee given by enforcing the timelock on coinbase transactions, this would
have to be perpetuated for the Consensus Cleanup.
[BIP30]: https://github.com/bitcoin/bips/blob/master/bip-0030.mediawiki
[BIP-XXXX]: https://github.com/TheBlueMatt/bips/blob/7f9670b643b7c943a0cc6d2197d3eabe661050c2/bip-XXXX.mediawiki
@@ -242,3 +249,4 @@ notably of Bitcoin Core but also of all other implementations the authors are aw
[Core 29.0]: https://bitcoincore.org/en/releases/29.0
[inquisition-implem]: https://github.com/darosior/bitcoin/tree/2509_inquisition_consensus_cleanup
[Core 30.0]: https://bitcoincore.org/en/releases/30.0
[Core validation.cpp BIP34]: https://github.com/bitcoin/bitcoin/blob/390e7d61bd531505bb3d13f38316c282b85ed1dd/src/validation.cpp#L2401-L2459