Remove Taproot activation height

Drop DEPLOYMENT_TAPROOT from consensus.vDeployments.

Bump MinBIP9WarningHeight.

Clarify what is considered a BuriedDeployment and
drop taproot from getdeploymentinfo RPC.

Add a test to getblocktemplate to ensure the taproot
rule is still set.

Co-Authored-By: MarcoFalke <*~=`'#}+{/-|&$^_@721217.xyz>

doc/bips.md

@@ -58,7 +58,8 @@ BIPs that are implemented by Bitcoin Core:
   Validation rules for Taproot (including Schnorr signatures and Tapscript
   leaves) are implemented as of **v0.21.0** ([PR 19953](https://github.com/bitcoin/bitcoin/pull/19953)),
   with mainnet activation as of **v0.21.1** ([PR 21377](https://github.com/bitcoin/bitcoin/pull/21377),
-  [PR 21686](https://github.com/bitcoin/bitcoin/pull/21686)).
+  [PR 21686](https://github.com/bitcoin/bitcoin/pull/21686)),
+  always active as of **v24.0** ([PR 23536](https://github.com/bitcoin/bitcoin/pull/23536)).
 * [`BIP 350`](https://github.com/bitcoin/bips/blob/master/bip-0350.mediawiki): Addresses for native v1+ segregated Witness outputs use Bech32m instead of Bech32 as of **v22.0** ([PR 20861](https://github.com/bitcoin/bitcoin/pull/20861)).
 * [`BIP 371`](https://github.com/bitcoin/bips/blob/master/bip-0371.mediawiki): Taproot fields for PSBT as of **v24.0** ([PR 22558](https://github.com/bitcoin/bitcoin/pull/22558)).
 * [`BIP 379`](https://github.com/bitcoin/bips/blob/master/bip-0379.md): Miniscript was partially implemented in **v24.0** ([PR 24148](https://github.com/bitcoin/bitcoin/pull/24148)), and fully implemented as of **v26.0** ([PR 27255](https://github.com/bitcoin/bitcoin/pull/27255)).

doc/release-notes-26201.md

@@ -0,0 +1,4 @@
+RPC
+---
+
+- 'taproot' has been removed from 'getdeploymentinfo' because its historical activation height is no longer used anywhere in the codebase. (#26201)

src/consensus/params.h

@@ -18,6 +18,7 @@ namespace Consensus {
 /**
  * A buried deployment is one where the height of the activation has been hardcoded into
  * the client implementation long after the consensus change has activated. See BIP 90.
+ * Consensus changes for which the new rules are enforced from genesis are not listed here.
  */
 enum BuriedDeployment : int16_t {
     // buried deployments get negative values to avoid overlap with DeploymentPos
@@ -25,14 +26,16 @@ enum BuriedDeployment : int16_t {
     DEPLOYMENT_CLTV,
     DEPLOYMENT_DERSIG,
     DEPLOYMENT_CSV,
+    // SCRIPT_VERIFY_WITNESS is enforced from genesis, but the check for downloading
+    // missing witness data is not. BIP 147 also relies on hardcoded activation height.
     DEPLOYMENT_SEGWIT,
 };
 constexpr bool ValidDeployment(BuriedDeployment dep) { return dep <= DEPLOYMENT_SEGWIT; }
 
 enum DeploymentPos : uint16_t {
     DEPLOYMENT_TESTDUMMY,
-    DEPLOYMENT_TAPROOT, // Deployment of Schnorr/Taproot (BIPs 340-342)
     // NOTE: Also add new deployments to VersionBitsDeploymentInfo in deploymentinfo.cpp
+    // Removing an entry may require bumping MinBIP9WarningHeight.
     MAX_VERSION_BITS_DEPLOYMENTS
 };
 constexpr bool ValidDeployment(DeploymentPos dep) { return dep < MAX_VERSION_BITS_DEPLOYMENTS; }
@@ -95,7 +98,7 @@ struct Params {
      * BIP 16 exception blocks. */
     int SegwitHeight;
     /** Don't warn about unknown BIP 9 activations below this height.
-     * This prevents us from warning about the CSV and segwit activations. */
+     * This prevents us from warning about the CSV, segwit and taproot activations. */
     int MinBIP9WarningHeight;
     /**
      * Minimum blocks including miner confirmation of the total of 2016 blocks in a retargeting period,

src/deploymentinfo.cpp

@@ -13,10 +13,6 @@ const struct VBDeploymentInfo VersionBitsDeploymentInfo[Consensus::MAX_VERSION_B
         /*.name =*/ "testdummy",
         /*.gbt_force =*/ true,
     },
-    {
-        /*.name =*/ "taproot",
-        /*.gbt_force =*/ true,
-    },
 };
 
 std::string DeploymentName(Consensus::BuriedDeployment dep)

src/kernel/chainparams.cpp

@@ -97,7 +97,7 @@ public:
         consensus.BIP66Height = 363725; // 00000000000000000379eaa19dce8c9b722d46ae6a57c2f1a988119488b50931
         consensus.CSVHeight = 419328; // 000000000000000004a1b34462cb8aeebd5799177f7a29cf28f2d1961716b5b5
         consensus.SegwitHeight = 481824; // 0000000000000000001c8018d9cb3b742ef25114f27563e3fc4a1902167f9893
-        consensus.MinBIP9WarningHeight = 483840; // segwit activation height + miner confirmation window
+        consensus.MinBIP9WarningHeight = 711648; // taproot activation height + miner confirmation window
         consensus.powLimit = uint256{"00000000ffffffffffffffffffffffffffffffffffffffffffffffffffffffff"};
         consensus.nPowTargetTimespan = 14 * 24 * 60 * 60; // two weeks
         consensus.nPowTargetSpacing = 10 * 60;
@@ -111,12 +111,6 @@ public:
         consensus.vDeployments[Consensus::DEPLOYMENT_TESTDUMMY].nTimeout = Consensus::BIP9Deployment::NO_TIMEOUT;
         consensus.vDeployments[Consensus::DEPLOYMENT_TESTDUMMY].min_activation_height = 0; // No activation delay
 
-        // Deployment of Taproot (BIPs 340-342)
-        consensus.vDeployments[Consensus::DEPLOYMENT_TAPROOT].bit = 2;
-        consensus.vDeployments[Consensus::DEPLOYMENT_TAPROOT].nStartTime = 1619222400; // April 24th, 2021
-        consensus.vDeployments[Consensus::DEPLOYMENT_TAPROOT].nTimeout = 1628640000; // August 11th, 2021
-        consensus.vDeployments[Consensus::DEPLOYMENT_TAPROOT].min_activation_height = 709632; // Approximately November 12th, 2021
-
         consensus.nMinimumChainWork = uint256{"0000000000000000000000000000000000000000b1f3b93b65b16d035a82be84"};
         consensus.defaultAssumeValid = uint256{"00000000000000000001b658dd1120e82e66d2790811f89ede9742ada3ed6d77"}; // 886157
 
@@ -227,7 +221,7 @@ public:
         consensus.BIP66Height = 330776; // 000000002104c8c45e99a8853285a3b592602a3ccde2b832481da85e9e4ba182
         consensus.CSVHeight = 770112; // 00000000025e930139bac5c6c31a403776da130831ab85be56578f3fa75369bb
         consensus.SegwitHeight = 834624; // 00000000002b980fcd729daaa248fd9316a5200e9b367f4ff2c42453e84201ca
-        consensus.MinBIP9WarningHeight = 836640; // segwit activation height + miner confirmation window
+        consensus.MinBIP9WarningHeight = 2013984; // taproot activation height + miner confirmation window
         consensus.powLimit = uint256{"00000000ffffffffffffffffffffffffffffffffffffffffffffffffffffffff"};
         consensus.nPowTargetTimespan = 14 * 24 * 60 * 60; // two weeks
         consensus.nPowTargetSpacing = 10 * 60;
@@ -241,12 +235,6 @@ public:
         consensus.vDeployments[Consensus::DEPLOYMENT_TESTDUMMY].nTimeout = Consensus::BIP9Deployment::NO_TIMEOUT;
         consensus.vDeployments[Consensus::DEPLOYMENT_TESTDUMMY].min_activation_height = 0; // No activation delay
 
-        // Deployment of Taproot (BIPs 340-342)
-        consensus.vDeployments[Consensus::DEPLOYMENT_TAPROOT].bit = 2;
-        consensus.vDeployments[Consensus::DEPLOYMENT_TAPROOT].nStartTime = 1619222400; // April 24th, 2021
-        consensus.vDeployments[Consensus::DEPLOYMENT_TAPROOT].nTimeout = 1628640000; // August 11th, 2021
-        consensus.vDeployments[Consensus::DEPLOYMENT_TAPROOT].min_activation_height = 0; // No activation delay
-
         consensus.nMinimumChainWork = uint256{"0000000000000000000000000000000000000000000015f5e0c9f13455b0eb17"};
         consensus.defaultAssumeValid = uint256{"00000000000003fc7967410ba2d0a8a8d50daedc318d43e8baf1a9782c236a57"}; // 3974606
 
@@ -340,12 +328,6 @@ public:
         consensus.vDeployments[Consensus::DEPLOYMENT_TESTDUMMY].nTimeout = Consensus::BIP9Deployment::NO_TIMEOUT;
         consensus.vDeployments[Consensus::DEPLOYMENT_TESTDUMMY].min_activation_height = 0; // No activation delay
 
-        // Deployment of Taproot (BIPs 340-342)
-        consensus.vDeployments[Consensus::DEPLOYMENT_TAPROOT].bit = 2;
-        consensus.vDeployments[Consensus::DEPLOYMENT_TAPROOT].nStartTime = Consensus::BIP9Deployment::ALWAYS_ACTIVE;
-        consensus.vDeployments[Consensus::DEPLOYMENT_TAPROOT].nTimeout = Consensus::BIP9Deployment::NO_TIMEOUT;
-        consensus.vDeployments[Consensus::DEPLOYMENT_TAPROOT].min_activation_height = 0; // No activation delay
-
         consensus.nMinimumChainWork = uint256{"0000000000000000000000000000000000000000000001d6dce8651b6094e4c1"};
         consensus.defaultAssumeValid = uint256{"0000000000003ed4f08dbdf6f7d6b271a6bcffce25675cb40aa9fa43179a89f3"}; // 72600
 
@@ -480,12 +462,6 @@ public:
         consensus.vDeployments[Consensus::DEPLOYMENT_TESTDUMMY].nTimeout = Consensus::BIP9Deployment::NO_TIMEOUT;
         consensus.vDeployments[Consensus::DEPLOYMENT_TESTDUMMY].min_activation_height = 0; // No activation delay
 
-        // Activation of Taproot (BIPs 340-342)
-        consensus.vDeployments[Consensus::DEPLOYMENT_TAPROOT].bit = 2;
-        consensus.vDeployments[Consensus::DEPLOYMENT_TAPROOT].nStartTime = Consensus::BIP9Deployment::ALWAYS_ACTIVE;
-        consensus.vDeployments[Consensus::DEPLOYMENT_TAPROOT].nTimeout = Consensus::BIP9Deployment::NO_TIMEOUT;
-        consensus.vDeployments[Consensus::DEPLOYMENT_TAPROOT].min_activation_height = 0; // No activation delay
-
         // message start is defined as the first 4 bytes of the sha256d of the block script
         HashWriter h{};
         h << consensus.signet_challenge;
@@ -558,11 +534,6 @@ public:
         consensus.vDeployments[Consensus::DEPLOYMENT_TESTDUMMY].nTimeout = Consensus::BIP9Deployment::NO_TIMEOUT;
         consensus.vDeployments[Consensus::DEPLOYMENT_TESTDUMMY].min_activation_height = 0; // No activation delay
 
-        consensus.vDeployments[Consensus::DEPLOYMENT_TAPROOT].bit = 2;
-        consensus.vDeployments[Consensus::DEPLOYMENT_TAPROOT].nStartTime = Consensus::BIP9Deployment::ALWAYS_ACTIVE;
-        consensus.vDeployments[Consensus::DEPLOYMENT_TAPROOT].nTimeout = Consensus::BIP9Deployment::NO_TIMEOUT;
-        consensus.vDeployments[Consensus::DEPLOYMENT_TAPROOT].min_activation_height = 0; // No activation delay
-
         consensus.nMinimumChainWork = uint256{};
         consensus.defaultAssumeValid = uint256{};
 

src/rpc/blockchain.cpp

@@ -1407,7 +1407,6 @@ UniValue DeploymentInfo(const CBlockIndex* blockindex, const ChainstateManager&
     SoftForkDescPushBack(blockindex, softforks, chainman, Consensus::DEPLOYMENT_CSV);
     SoftForkDescPushBack(blockindex, softforks, chainman, Consensus::DEPLOYMENT_SEGWIT);
     SoftForkDescPushBack(blockindex, softforks, chainman, Consensus::DEPLOYMENT_TESTDUMMY);
-    SoftForkDescPushBack(blockindex, softforks, chainman, Consensus::DEPLOYMENT_TAPROOT);
     return softforks;
 }
 } // anon namespace
@@ -1415,7 +1414,8 @@ UniValue DeploymentInfo(const CBlockIndex* blockindex, const ChainstateManager&
 RPCHelpMan getdeploymentinfo()
 {
     return RPCHelpMan{"getdeploymentinfo",
-        "Returns an object containing various state info regarding deployments of consensus changes.",
+        "Returns an object containing various state info regarding deployments of consensus changes.\n"
+        "Consensus changes for which the new rules are enforced from genesis are not listed here.",
         {
             {"blockhash", RPCArg::Type::STR_HEX, RPCArg::Default{"hash of current chain tip"}, "The block hash at which to query deployment state"},
         },

src/rpc/mining.cpp

@@ -919,8 +919,14 @@ static RPCHelpMan getblocktemplate()
     result.pushKV("capabilities", std::move(aCaps));
 
     UniValue aRules(UniValue::VARR);
+    // See getblocktemplate changes in BIP 9:
+    // ! indicates a more subtle change to the block structure or generation transaction
+    // Otherwise clients may assume the rule will not impact usage of the template as-is.
     aRules.push_back("csv");
-    if (!fPreSegWit) aRules.push_back("!segwit");
+    if (!fPreSegWit) {
+        aRules.push_back("!segwit");
+        aRules.push_back("taproot");
+    }
     if (consensusParams.signet_blocks) {
         // indicate to miner that they must understand signet rules
         // when attempting to mine with this template

test/functional/mining_basic.py

@@ -376,6 +376,9 @@ class MiningTest(BitcoinTestFramework):
         self.log.info("getblocktemplate: segwit rule must be set")
         assert_raises_rpc_error(-8, "getblocktemplate must be called with the segwit rule set", node.getblocktemplate, {})
 
+        self.log.info("getblocktemplate: result should set the right rules")
+        assert_equal(['csv', '!segwit', 'taproot'], self.nodes[0].getblocktemplate(NORMAL_GBT_REQUEST_PARAMS)['rules'])
+
         self.log.info("getblocktemplate: Test valid block")
         assert_template(node, block, None)
 

test/functional/rpc_blockchain.py

@@ -238,19 +238,6 @@ class BlockchainTest(BitcoinTestFramework):
                 },
                 'active': False
             },
-            'taproot': {
-                'type': 'bip9',
-                'bip9': {
-                    'start_time': -1,
-                    'timeout': 9223372036854775807,
-                    'min_activation_height': 0,
-                    'status': 'active',
-                    'status_next': 'active',
-                    'since': 0,
-                },
-                'height': 0,
-                'active': True
-            }
           }
         })