Introduce convenience type CTransactionRef

16 files changed, 63 insertions, 57 deletions

diff --git a/src/blockencodings.cpp b/src/blockencodings.cpp
index fac52474ec..f14ae1c412 100644
--- a/src/blockencodings.cpp
+++ b/src/blockencodings.cpp
@@ -142,7 +142,7 @@ bool PartiallyDownloadedBlock::IsTxAvailable(size_t index) const {
     return txn_available[index] ? true : false;
 }
 
-ReadStatus PartiallyDownloadedBlock::FillBlock(CBlock& block, const std::vector<std::shared_ptr<const CTransaction>>& vtx_missing) const {
+ReadStatus PartiallyDownloadedBlock::FillBlock(CBlock& block, const std::vector<CTransactionRef>& vtx_missing) const {
     assert(!header.IsNull());
     block = header;
     block.vtx.resize(txn_available.size());
diff --git a/src/blockencodings.h b/src/blockencodings.h
index ffe189a940..27baf1f8f8 100644
--- a/src/blockencodings.h
+++ b/src/blockencodings.h
@@ -14,9 +14,9 @@ class CTxMemPool;
 // Dumb helper to handle CTransaction compression at serialize-time
 struct TransactionCompressor {
 private:
-    std::shared_ptr<const CTransaction>& tx;
+    CTransactionRef& tx;
 public:
-    TransactionCompressor(std::shared_ptr<const CTransaction>& txIn) : tx(txIn) {}
+    TransactionCompressor(CTransactionRef& txIn) : tx(txIn) {}
 
     ADD_SERIALIZE_METHODS;
 
@@ -72,7 +72,7 @@ class BlockTransactions {
 public:
     // A BlockTransactions message
     uint256 blockhash;
-    std::vector<std::shared_ptr<const CTransaction>> txn;
+    std::vector<CTransactionRef> txn;
 
     BlockTransactions() {}
     BlockTransactions(const BlockTransactionsRequest& req) :
@@ -104,7 +104,7 @@ struct PrefilledTransaction {
     // Used as an offset since last prefilled tx in CBlockHeaderAndShortTxIDs,
     // as a proper transaction-in-block-index in PartiallyDownloadedBlock
     uint16_t index;
-    std::shared_ptr<const CTransaction> tx;
+    CTransactionRef tx;
 
     ADD_SERIALIZE_METHODS;
 
@@ -193,7 +193,7 @@ public:
 
 class PartiallyDownloadedBlock {
 protected:
-    std::vector<std::shared_ptr<const CTransaction> > txn_available;
+    std::vector<CTransactionRef> txn_available;
     size_t prefilled_count = 0, mempool_count = 0;
     CTxMemPool* pool;
 public:
@@ -202,7 +202,7 @@ public:
 
     ReadStatus InitData(const CBlockHeaderAndShortTxIDs& cmpctblock);
     bool IsTxAvailable(size_t index) const;
-    ReadStatus FillBlock(CBlock& block, const std::vector<std::shared_ptr<const CTransaction>>& vtx_missing) const;
+    ReadStatus FillBlock(CBlock& block, const std::vector<CTransactionRef>& vtx_missing) const;
 };
 
 #endif
diff --git a/src/chainparams.cpp b/src/chainparams.cpp
index 77eb586b67..3b3c0a5d3e 100644
--- a/src/chainparams.cpp
+++ b/src/chainparams.cpp
@@ -31,7 +31,7 @@ static CBlock CreateGenesisBlock(const char* pszTimestamp, const CScript& genesi
     genesis.nBits    = nBits;
     genesis.nNonce   = nNonce;
     genesis.nVersion = nVersion;
-    genesis.vtx.push_back(std::make_shared<const CTransaction>(std::move(txNew)));
+    genesis.vtx.push_back(MakeTransactionRef(std::move(txNew)));
     genesis.hashPrevBlock.SetNull();
     genesis.hashMerkleRoot = BlockMerkleRoot(genesis);
     return genesis;
diff --git a/src/main.cpp b/src/main.cpp
index 7b84ab7ba1..aeeb31ec40 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -233,7 +233,7 @@ namespace {
     int nPeersWithValidatedDownloads = 0;
 
     /** Relay map, protected by cs_main. */
-    typedef std::map<uint256, std::shared_ptr<const CTransaction>> MapRelay;
+    typedef std::map<uint256, CTransactionRef> MapRelay;
     MapRelay mapRelay;
     /** Expiration-time ordered list of (expire time, relay map entry) pairs, protected by cs_main). */
     std::deque<std::pair<int64_t, MapRelay::iterator>> vRelayExpiration;
@@ -1639,7 +1639,7 @@ bool GetTransaction(const uint256 &hash, CTransaction &txOut, const Consensus::P
 
     LOCK(cs_main);
 
-    std::shared_ptr<const CTransaction> ptx = mempool.get(hash);
+    CTransactionRef ptx = mempool.get(hash);
     if (ptx)
     {
         txOut = *ptx;
@@ -2845,7 +2845,7 @@ static int64_t nTimePostConnect = 0;
  * Connect a new block to chainActive. pblock is either NULL or a pointer to a CBlock
  * corresponding to pindexNew, to bypass loading it again from disk.
  */
-bool static ConnectTip(CValidationState& state, const CChainParams& chainparams, CBlockIndex* pindexNew, const CBlock* pblock, std::vector<std::shared_ptr<const CTransaction>> &txConflicted, std::vector<std::tuple<std::shared_ptr<const CTransaction>,CBlockIndex*,int>> &txChanged)
+bool static ConnectTip(CValidationState& state, const CChainParams& chainparams, CBlockIndex* pindexNew, const CBlock* pblock, std::vector<CTransactionRef> &txConflicted, std::vector<std::tuple<CTransactionRef,CBlockIndex*,int>> &txChanged)
 {
     assert(pindexNew->pprev == chainActive.Tip());
     // Read block from disk.
@@ -2968,7 +2968,7 @@ static void PruneBlockIndexCandidates() {
  * Try to make some progress towards making pindexMostWork the active block.
  * pblock is either NULL or a pointer to a CBlock corresponding to pindexMostWork.
  */
-static bool ActivateBestChainStep(CValidationState& state, const CChainParams& chainparams, CBlockIndex* pindexMostWork, const CBlock* pblock, bool& fInvalidFound, std::vector<std::shared_ptr<const CTransaction>>& txConflicted, std::vector<std::tuple<std::shared_ptr<const CTransaction>,CBlockIndex*,int>>& txChanged)
+static bool ActivateBestChainStep(CValidationState& state, const CChainParams& chainparams, CBlockIndex* pindexMostWork, const CBlock* pblock, bool& fInvalidFound, std::vector<CTransactionRef>& txConflicted, std::vector<std::tuple<CTransactionRef,CBlockIndex*,int>>& txChanged)
 {
     AssertLockHeld(cs_main);
     const CBlockIndex *pindexOldTip = chainActive.Tip();
@@ -3069,7 +3069,7 @@ static void NotifyHeaderTip() {
 bool ActivateBestChain(CValidationState &state, const CChainParams& chainparams, const CBlock *pblock) {
     CBlockIndex *pindexMostWork = NULL;
     CBlockIndex *pindexNewTip = NULL;
-    std::vector<std::tuple<std::shared_ptr<const CTransaction>,CBlockIndex*,int>> txChanged;
+    std::vector<std::tuple<CTransactionRef,CBlockIndex*,int>> txChanged;
     if (pblock)
         txChanged.reserve(pblock->vtx.size());
     do {
@@ -3079,7 +3079,7 @@ bool ActivateBestChain(CValidationState &state, const CChainParams& chainparams,
             break;
 
         const CBlockIndex *pindexFork;
-        std::vector<std::shared_ptr<const CTransaction>> txConflicted;
+        std::vector<CTransactionRef> txConflicted;
         bool fInitialDownload;
         {
             LOCK(cs_main);
@@ -3523,7 +3523,7 @@ void UpdateUncommittedBlockStructures(CBlock& block, const CBlockIndex* pindexPr
         tx.wit.vtxinwit.resize(1);
         tx.wit.vtxinwit[0].scriptWitness.stack.resize(1);
         tx.wit.vtxinwit[0].scriptWitness.stack[0] = nonce;
-        block.vtx[0] = std::make_shared<const CTransaction>(std::move(tx));
+        block.vtx[0] = MakeTransactionRef(std::move(tx));
     }
 }
 
diff --git a/src/miner.cpp b/src/miner.cpp
index 2b65cbc65e..c40b12cd8e 100644
--- a/src/miner.cpp
+++ b/src/miner.cpp
@@ -178,7 +178,7 @@ std::unique_ptr<CBlockTemplate> BlockAssembler::CreateNewBlock(const CScript& sc
     coinbaseTx.vout[0].scriptPubKey = scriptPubKeyIn;
     coinbaseTx.vout[0].nValue = nFees + GetBlockSubsidy(nHeight, chainparams.GetConsensus());
     coinbaseTx.vin[0].scriptSig = CScript() << nHeight << OP_0;
-    pblock->vtx[0] = std::make_shared<const CTransaction>(std::move(coinbaseTx));
+    pblock->vtx[0] = MakeTransactionRef(std::move(coinbaseTx));
     pblocktemplate->vchCoinbaseCommitment = GenerateCoinbaseCommitment(*pblock, pindexPrev, chainparams.GetConsensus());
     pblocktemplate->vTxFees[0] = -nFees;
 
@@ -605,6 +605,6 @@ void IncrementExtraNonce(CBlock* pblock, const CBlockIndex* pindexPrev, unsigned
     txCoinbase.vin[0].scriptSig = (CScript() << nHeight << CScriptNum(nExtraNonce)) + COINBASE_FLAGS;
     assert(txCoinbase.vin[0].scriptSig.size() <= 100);
 
-    pblock->vtx[0] = std::make_shared<const CTransaction>(std::move(txCoinbase));
+    pblock->vtx[0] = MakeTransactionRef(std::move(txCoinbase));
     pblock->hashMerkleRoot = BlockMerkleRoot(*pblock);
 }
diff --git a/src/primitives/block.h b/src/primitives/block.h
index 45b4895eba..b037fc839c 100644
--- a/src/primitives/block.h
+++ b/src/primitives/block.h
@@ -73,7 +73,7 @@ class CBlock : public CBlockHeader
 {
 public:
     // network and disk
-    std::vector<std::shared_ptr<const CTransaction>> vtx;
+    std::vector<CTransactionRef> vtx;
 
     // memory only
     mutable bool fChecked;
diff --git a/src/primitives/transaction.h b/src/primitives/transaction.h
index 015a89ff10..0fa85a1519 100644
--- a/src/primitives/transaction.h
+++ b/src/primitives/transaction.h
@@ -475,6 +475,12 @@ struct CMutableTransaction
     uint256 GetHash() const;
 };
 
+typedef std::shared_ptr<const CTransaction> CTransactionRef;
+static inline CTransactionRef MakeTransactionRef() { return std::make_shared<const CTransaction>(); }
+template <typename Tx> static inline CTransactionRef MakeTransactionRef(Tx&& txIn) { return std::make_shared<const CTransaction>(std::forward<Tx>(txIn)); }
+static inline CTransactionRef MakeTransactionRef(const CTransactionRef& txIn) { return txIn; }
+static inline CTransactionRef MakeTransactionRef(CTransactionRef&& txIn) { return std::move(txIn); }
+
 /** Compute the weight of a transaction, as defined by BIP 141 */
 int64_t GetTransactionWeight(const CTransaction &tx);
 
diff --git a/src/test/blockencodings_tests.cpp b/src/test/blockencodings_tests.cpp
index 6899bd6328..b013cda6d7 100644
--- a/src/test/blockencodings_tests.cpp
+++ b/src/test/blockencodings_tests.cpp
@@ -26,21 +26,21 @@ static CBlock BuildBlockTestCase() {
     tx.vout[0].nValue = 42;
 
     block.vtx.resize(3);
-    block.vtx[0] = std::make_shared<const CTransaction>(tx);
+    block.vtx[0] = MakeTransactionRef(tx);
     block.nVersion = 42;
     block.hashPrevBlock = GetRandHash();
     block.nBits = 0x207fffff;
 
     tx.vin[0].prevout.hash = GetRandHash();
     tx.vin[0].prevout.n = 0;
-    block.vtx[1] = std::make_shared<const CTransaction>(tx);
+    block.vtx[1] = MakeTransactionRef(tx);
 
     tx.vin.resize(10);
     for (size_t i = 0; i < tx.vin.size(); i++) {
         tx.vin[i].prevout.hash = GetRandHash();
         tx.vin[i].prevout.n = 0;
     }
-    block.vtx[2] = std::make_shared<const CTransaction>(tx);
+    block.vtx[2] = MakeTransactionRef(tx);
 
     bool mutated;
     block.hashMerkleRoot = BlockMerkleRoot(block, &mutated);
@@ -80,12 +80,12 @@ BOOST_AUTO_TEST_CASE(SimpleRoundTripTest)
 
         BOOST_CHECK_EQUAL(pool.mapTx.find(block.vtx[2]->GetHash())->GetSharedTx().use_count(), SHARED_TX_OFFSET + 1);
 
-        std::vector<std::shared_ptr<const CTransaction>> removed;
+        std::vector<CTransactionRef> removed;
         pool.removeRecursive(*block.vtx[2], &removed);
         BOOST_CHECK_EQUAL(removed.size(), 1);
 
         CBlock block2;
-        std::vector<std::shared_ptr<const CTransaction>> vtx_missing;
+        std::vector<CTransactionRef> vtx_missing;
         BOOST_CHECK(partialBlock.FillBlock(block2, vtx_missing) == READ_STATUS_INVALID); // No transactions
 
         vtx_missing.push_back(block.vtx[2]); // Wrong transaction
@@ -181,7 +181,7 @@ BOOST_AUTO_TEST_CASE(NonCoinbasePreforwardRTTest)
         BOOST_CHECK_EQUAL(pool.mapTx.find(block.vtx[2]->GetHash())->GetSharedTx().use_count(), SHARED_TX_OFFSET + 1);
 
         CBlock block2;
-        std::vector<std::shared_ptr<const CTransaction>> vtx_missing;
+        std::vector<CTransactionRef> vtx_missing;
         BOOST_CHECK(partialBlock.FillBlock(block2, vtx_missing) == READ_STATUS_INVALID); // No transactions
 
         vtx_missing.push_back(block.vtx[1]); // Wrong transaction
@@ -240,7 +240,7 @@ BOOST_AUTO_TEST_CASE(SufficientPreforwardRTTest)
         BOOST_CHECK_EQUAL(pool.mapTx.find(block.vtx[1]->GetHash())->GetSharedTx().use_count(), SHARED_TX_OFFSET + 1);
 
         CBlock block2;
-        std::vector<std::shared_ptr<const CTransaction>> vtx_missing;
+        std::vector<CTransactionRef> vtx_missing;
         BOOST_CHECK(partialBlock.FillBlock(block2, vtx_missing) == READ_STATUS_OK);
         BOOST_CHECK_EQUAL(block.GetHash().ToString(), block2.GetHash().ToString());
         bool mutated;
@@ -266,7 +266,7 @@ BOOST_AUTO_TEST_CASE(EmptyBlockRoundTripTest)
 
     CBlock block;
     block.vtx.resize(1);
-    block.vtx[0] = std::make_shared<const CTransaction>(std::move(coinbase));
+    block.vtx[0] = MakeTransactionRef(std::move(coinbase));
     block.nVersion = 42;
     block.hashPrevBlock = GetRandHash();
     block.nBits = 0x207fffff;
@@ -291,7 +291,7 @@ BOOST_AUTO_TEST_CASE(EmptyBlockRoundTripTest)
         BOOST_CHECK(partialBlock.IsTxAvailable(0));
 
         CBlock block2;
-        std::vector<std::shared_ptr<const CTransaction>> vtx_missing;
+        std::vector<CTransactionRef> vtx_missing;
         BOOST_CHECK(partialBlock.FillBlock(block2, vtx_missing) == READ_STATUS_OK);
         BOOST_CHECK_EQUAL(block.GetHash().ToString(), block2.GetHash().ToString());
         BOOST_CHECK_EQUAL(block.hashMerkleRoot.ToString(), BlockMerkleRoot(block2, &mutated).ToString());
diff --git a/src/test/mempool_tests.cpp b/src/test/mempool_tests.cpp
index 4a6a060012..1faf8b6aeb 100644
--- a/src/test/mempool_tests.cpp
+++ b/src/test/mempool_tests.cpp
@@ -55,7 +55,7 @@ BOOST_AUTO_TEST_CASE(MempoolRemoveTest)
 
 
     CTxMemPool testPool(CFeeRate(0));
-    std::vector<std::shared_ptr<const CTransaction>> removed;
+    std::vector<CTransactionRef> removed;
 
     // Nothing in pool, remove should do nothing:
     testPool.removeRecursive(txParent, &removed);
@@ -410,8 +410,8 @@ BOOST_AUTO_TEST_CASE(MempoolAncestorIndexingTest)
     CheckSort<ancestor_score>(pool, sortedOrder);
 
     /* after tx6 is mined, tx7 should move up in the sort */
-    std::vector<std::shared_ptr<const CTransaction>> vtx;
-    vtx.push_back(std::make_shared<const CTransaction>(tx6));
+    std::vector<CTransactionRef> vtx;
+    vtx.push_back(MakeTransactionRef(tx6));
     pool.removeForBlock(vtx, 1, NULL, false);
 
     sortedOrder.erase(sortedOrder.begin()+1);
@@ -546,7 +546,7 @@ BOOST_AUTO_TEST_CASE(MempoolSizeLimitTest)
     pool.addUnchecked(tx5.GetHash(), entry.Fee(1000LL).FromTx(tx5, &pool));
     pool.addUnchecked(tx7.GetHash(), entry.Fee(9000LL).FromTx(tx7, &pool));
 
-    std::vector<std::shared_ptr<const CTransaction>> vtx;
+    std::vector<CTransactionRef> vtx;
     SetMockTime(42);
     SetMockTime(42 + CTxMemPool::ROLLING_FEE_HALFLIFE);
     BOOST_CHECK_EQUAL(pool.GetMinFee(1).GetFeePerK(), maxFeeRateRemoved.GetFeePerK() + 1000);
diff --git a/src/test/merkle_tests.cpp b/src/test/merkle_tests.cpp
index 8aea571e12..55e6852a15 100644
--- a/src/test/merkle_tests.cpp
+++ b/src/test/merkle_tests.cpp
@@ -15,7 +15,7 @@ static uint256 BlockBuildMerkleTree(const CBlock& block, bool* fMutated, std::ve
 {
     vMerkleTree.clear();
     vMerkleTree.reserve(block.vtx.size() * 2 + 16); // Safe upper bound for the number of total nodes.
-    for (std::vector<std::shared_ptr<const CTransaction>>::const_iterator it(block.vtx.begin()); it != block.vtx.end(); ++it)
+    for (std::vector<CTransactionRef>::const_iterator it(block.vtx.begin()); it != block.vtx.end(); ++it)
         vMerkleTree.push_back((*it)->GetHash());
     int j = 0;
     bool mutated = false;
@@ -86,7 +86,7 @@ BOOST_AUTO_TEST_CASE(merkle_test)
             for (int j = 0; j < ntx; j++) {
                 CMutableTransaction mtx;
                 mtx.nLockTime = j;
-                block.vtx[j] = std::make_shared<const CTransaction>(mtx);
+                block.vtx[j] = MakeTransactionRef(std::move(mtx));
             }
             // Compute the root of the block before mutating it.
             bool unmutatedMutated = false;
diff --git a/src/test/miner_tests.cpp b/src/test/miner_tests.cpp
index 56dab347fb..aea8920936 100644
--- a/src/test/miner_tests.cpp
+++ b/src/test/miner_tests.cpp
@@ -77,7 +77,7 @@ bool TestSequenceLocks(const CTransaction &tx, int flags)
 // Implemented as an additional function, rather than a separate test case,
 // to allow reusing the blockchain created in CreateNewBlock_validity.
 // Note that this test assumes blockprioritysize is 0.
-void TestPackageSelection(const CChainParams& chainparams, CScript scriptPubKey, std::vector<std::shared_ptr<const CTransaction>>& txFirst)
+void TestPackageSelection(const CChainParams& chainparams, CScript scriptPubKey, std::vector<CTransactionRef>& txFirst)
 {
     // Test the ancestor feerate transaction selection.
     TestMemPoolEntryHelper entry;
@@ -203,7 +203,7 @@ BOOST_AUTO_TEST_CASE(CreateNewBlock_validity)
     // We can't make transactions until we have inputs
     // Therefore, load 100 blocks :)
     int baseheight = 0;
-    std::vector<std::shared_ptr<const CTransaction>> txFirst;
+    std::vector<CTransactionRef> txFirst;
     for (unsigned int i = 0; i < sizeof(blockinfo)/sizeof(*blockinfo); ++i)
     {
         CBlock *pblock = &pblocktemplate->block; // pointer for convenience
@@ -215,7 +215,7 @@ BOOST_AUTO_TEST_CASE(CreateNewBlock_validity)
         txCoinbase.vin[0].scriptSig.push_back(blockinfo[i].extranonce);
         txCoinbase.vin[0].scriptSig.push_back(chainActive.Height());
         txCoinbase.vout[0].scriptPubKey = CScript();
-        pblock->vtx[0] = std::make_shared<const CTransaction>(std::move(txCoinbase));
+        pblock->vtx[0] = MakeTransactionRef(std::move(txCoinbase));
         if (txFirst.size() == 0)
             baseheight = chainActive.Height();
         if (txFirst.size() < 4)
diff --git a/src/test/pmt_tests.cpp b/src/test/pmt_tests.cpp
index 1552cb4baf..e6b689bc6c 100644
--- a/src/test/pmt_tests.cpp
+++ b/src/test/pmt_tests.cpp
@@ -45,7 +45,7 @@ BOOST_AUTO_TEST_CASE(pmt_test1)
         for (unsigned int j=0; j<nTx; j++) {
             CMutableTransaction tx;
             tx.nLockTime = j; // actual transaction data doesn't matter; just make the nLockTime's unique
-            block.vtx.push_back(std::make_shared<const CTransaction>(tx));
+            block.vtx.push_back(MakeTransactionRef(std::move(tx)));
         }
 
         // calculate actual merkle root and height
diff --git a/src/test/policyestimator_tests.cpp b/src/test/policyestimator_tests.cpp
index 08e5e774e1..7dc8f226c9 100644
--- a/src/test/policyestimator_tests.cpp
+++ b/src/test/policyestimator_tests.cpp
@@ -45,7 +45,7 @@ BOOST_AUTO_TEST_CASE(BlockPolicyEstimates)
     CFeeRate baseRate(basefee, GetVirtualTransactionSize(tx));
 
     // Create a fake block
-    std::vector<std::shared_ptr<const CTransaction>> block;
+    std::vector<CTransactionRef> block;
     int blocknum = 0;
 
     // Loop through 200 blocks
@@ -66,7 +66,7 @@ BOOST_AUTO_TEST_CASE(BlockPolicyEstimates)
             // 9/10 blocks add 2nd highest and so on until ...
             // 1/10 blocks add lowest fee transactions
             while (txHashes[9-h].size()) {
-                std::shared_ptr<const CTransaction> ptx = mpool.get(txHashes[9-h].back());
+                CTransactionRef ptx = mpool.get(txHashes[9-h].back());
                 if (ptx)
                     block.push_back(ptx);
                 txHashes[9-h].pop_back();
@@ -143,7 +143,7 @@ BOOST_AUTO_TEST_CASE(BlockPolicyEstimates)
     // Estimates should still not be below original
     for (int j = 0; j < 10; j++) {
         while(txHashes[j].size()) {
-            std::shared_ptr<const CTransaction> ptx = mpool.get(txHashes[j].back());
+            CTransactionRef ptx = mpool.get(txHashes[j].back());
             if (ptx)
                 block.push_back(ptx);
             txHashes[j].pop_back();
@@ -163,7 +163,7 @@ BOOST_AUTO_TEST_CASE(BlockPolicyEstimates)
                 tx.vin[0].prevout.n = 10000*blocknum+100*j+k;
                 uint256 hash = tx.GetHash();
                 mpool.addUnchecked(hash, entry.Fee(feeV[j]).Time(GetTime()).Priority(0).Height(blocknum).FromTx(tx, &mpool));
-                std::shared_ptr<const CTransaction> ptx = mpool.get(hash);
+                CTransactionRef ptx = mpool.get(hash);
                 if (ptx)
                     block.push_back(ptx);
 
diff --git a/src/test/test_bitcoin.cpp b/src/test/test_bitcoin.cpp
index f932cbe238..6cbe314a76 100644
--- a/src/test/test_bitcoin.cpp
+++ b/src/test/test_bitcoin.cpp
@@ -119,7 +119,7 @@ TestChain100Setup::CreateAndProcessBlock(const std::vector<CMutableTransaction>&
     // Replace mempool-selected txns with just coinbase plus passed-in txns:
     block.vtx.resize(1);
     BOOST_FOREACH(const CMutableTransaction& tx, txns)
-        block.vtx.push_back(std::make_shared<const CTransaction>(tx));
+        block.vtx.push_back(MakeTransactionRef(tx));
     // IncrementExtraNonce creates a valid coinbase and merkleRoot
     unsigned int extraNonce = 0;
     IncrementExtraNonce(&block, chainActive.Tip(), extraNonce);
diff --git a/src/txmempool.cpp b/src/txmempool.cpp
index fff20a609d..417a88cbef 100644
--- a/src/txmempool.cpp
+++ b/src/txmempool.cpp
@@ -24,7 +24,7 @@ CTxMemPoolEntry::CTxMemPoolEntry(const CTransaction& _tx, const CAmount& _nFee,
                                  int64_t _nTime, double _entryPriority, unsigned int _entryHeight,
                                  bool poolHasNoInputsOf, CAmount _inChainInputValue,
                                  bool _spendsCoinbase, int64_t _sigOpsCost, LockPoints lp):
-    tx(std::make_shared<CTransaction>(_tx)), nFee(_nFee), nTime(_nTime), entryPriority(_entryPriority), entryHeight(_entryHeight),
+    tx(MakeTransactionRef(_tx)), nFee(_nFee), nTime(_nTime), entryPriority(_entryPriority), entryHeight(_entryHeight),
     hadNoDependencies(poolHasNoInputsOf), inChainInputValue(_inChainInputValue),
     spendsCoinbase(_spendsCoinbase), sigOpCost(_sigOpsCost), lockPoints(lp)
 {
@@ -503,7 +503,7 @@ void CTxMemPool::CalculateDescendants(txiter entryit, setEntries &setDescendants
     }
 }
 
-void CTxMemPool::removeRecursive(const CTransaction &origTx, std::vector<std::shared_ptr<const CTransaction>>* removed)
+void CTxMemPool::removeRecursive(const CTransaction &origTx, std::vector<CTransactionRef>* removed)
 {
     // Remove transaction from memory pool
     {
@@ -576,7 +576,7 @@ void CTxMemPool::removeForReorg(const CCoinsViewCache *pcoins, unsigned int nMem
     RemoveStaged(setAllRemoves, false);
 }
 
-void CTxMemPool::removeConflicts(const CTransaction &tx, std::vector<std::shared_ptr<const CTransaction>>* removed)
+void CTxMemPool::removeConflicts(const CTransaction &tx, std::vector<CTransactionRef>* removed)
 {
     // Remove transactions which depend on inputs of tx, recursively
     LOCK(cs);
@@ -596,8 +596,8 @@ void CTxMemPool::removeConflicts(const CTransaction &tx, std::vector<std::shared
 /**
  * Called when a block is connected. Removes from mempool and updates the miner fee estimator.
  */
-void CTxMemPool::removeForBlock(const std::vector<shared_ptr<const CTransaction>>& vtx, unsigned int nBlockHeight,
-                                std::vector<std::shared_ptr<const CTransaction>>* conflicts, bool fCurrentEstimate)
+void CTxMemPool::removeForBlock(const std::vector<CTransactionRef>& vtx, unsigned int nBlockHeight,
+                                std::vector<CTransactionRef>* conflicts, bool fCurrentEstimate)
 {
     LOCK(cs);
     std::vector<CTxMemPoolEntry> entries;
@@ -851,7 +851,7 @@ std::vector<TxMempoolInfo> CTxMemPool::infoAll() const
     return ret;
 }
 
-std::shared_ptr<const CTransaction> CTxMemPool::get(const uint256& hash) const
+CTransactionRef CTxMemPool::get(const uint256& hash) const
 {
     LOCK(cs);
     indexed_transaction_set::const_iterator i = mapTx.find(hash);
@@ -978,7 +978,7 @@ bool CCoinsViewMemPool::GetCoins(const uint256 &txid, CCoins &coins) const {
     // If an entry in the mempool exists, always return that one, as it's guaranteed to never
     // conflict with the underlying cache, and it cannot have pruned entries (as it contains full)
     // transactions. First checking the underlying cache risks returning a pruned entry instead.
-    shared_ptr<const CTransaction> ptx = mempool.get(txid);
+    CTransactionRef ptx = mempool.get(txid);
     if (ptx) {
         coins = CCoins(*ptx, MEMPOOL_HEIGHT);
         return true;
diff --git a/src/txmempool.h b/src/txmempool.h
index 6952cc9006..29b59363a2 100644
--- a/src/txmempool.h
+++ b/src/txmempool.h
@@ -80,7 +80,7 @@ class CTxMemPool;
 class CTxMemPoolEntry
 {
 private:
-    std::shared_ptr<const CTransaction> tx;
+    CTransactionRef tx;
     CAmount nFee;              //!< Cached to avoid expensive parent-transaction lookups
     size_t nTxWeight;          //!< ... and avoid recomputing tx weight (also used for GetTxSize())
     size_t nModSize;           //!< ... and modified size for priority
@@ -118,7 +118,7 @@ public:
     CTxMemPoolEntry(const CTxMemPoolEntry& other);
 
     const CTransaction& GetTx() const { return *this->tx; }
-    std::shared_ptr<const CTransaction> GetSharedTx() const { return this->tx; }
+    CTransactionRef GetSharedTx() const { return this->tx; }
     /**
      * Fast calculation of lower bound of current priority as update
      * from entry priority. Only inputs that were originally in-chain will age.
@@ -322,7 +322,7 @@ class CBlockPolicyEstimator;
 struct TxMempoolInfo
 {
     /** The transaction itself */
-    std::shared_ptr<const CTransaction> tx;
+    CTransactionRef tx;
 
     /** Time the transaction entered the mempool. */
     int64_t nTime;
@@ -527,11 +527,11 @@ public:
     bool addUnchecked(const uint256& hash, const CTxMemPoolEntry &entry, bool fCurrentEstimate = true);
     bool addUnchecked(const uint256& hash, const CTxMemPoolEntry &entry, setEntries &setAncestors, bool fCurrentEstimate = true);
 
-    void removeRecursive(const CTransaction &tx, std::vector<std::shared_ptr<const CTransaction>>* removed = NULL);
+    void removeRecursive(const CTransaction &tx, std::vector<CTransactionRef>* removed = NULL);
     void removeForReorg(const CCoinsViewCache *pcoins, unsigned int nMemPoolHeight, int flags);
-    void removeConflicts(const CTransaction &tx, std::vector<std::shared_ptr<const CTransaction>>* removed = NULL);
-    void removeForBlock(const std::vector<std::shared_ptr<const CTransaction>>& vtx, unsigned int nBlockHeight,
-                        std::vector<std::shared_ptr<const CTransaction>>* conflicts = NULL, bool fCurrentEstimate = true);
+    void removeConflicts(const CTransaction &tx, std::vector<CTransactionRef>* removed = NULL);
+    void removeForBlock(const std::vector<CTransactionRef>& vtx, unsigned int nBlockHeight,
+                        std::vector<CTransactionRef>* conflicts = NULL, bool fCurrentEstimate = true);
     void clear();
     void _clear(); //lock free
     bool CompareDepthAndScore(const uint256& hasha, const uint256& hashb);
@@ -623,7 +623,7 @@ public:
         return (mapTx.count(hash) != 0);
     }
 
-    std::shared_ptr<const CTransaction> get(const uint256& hash) const;
+    CTransactionRef get(const uint256& hash) const;
     TxMempoolInfo info(const uint256& hash) const;
     std::vector<TxMempoolInfo> infoAll() const;