refactor: trivial fixes for dead, useless code and minor fixes for dash specific code (#5793)

## Issue being fixed or feature implemented
Dead-code, useless conditions can be potential source of bug.

## What was done?
See each particular commit.
This particular commit "fix: check ptr in assert before usage" fixes
potential UB - `assert` is better than UB.
All other commits are not fixing any real issue, just to tidy-up code a
bit or to shut a potential warning.


## How Has This Been Tested?
Run unit/functional tests.

## Breaking Changes
N/A

## Checklist:
- [x] I have performed a self-review of my own code
- [ ] I have commented my code, particularly in hard-to-understand areas
- [ ] I have added or updated relevant unit/integration/functional/e2e
tests
- [ ] I have made corresponding changes to the documentation
- [x] I have assigned this pull request to a milestone

Author: knst

src/evo/cbtx.h

@@ -42,7 +42,7 @@ class CCbTx
     int32_t nHeight{0};
     uint256 merkleRootMNList;
     uint256 merkleRootQuorums;
-    uint32_t bestCLHeightDiff;
+    uint32_t bestCLHeightDiff{0};
     CBLSSignature bestCLSignature;
     CAmount creditPoolBalance{0};
 

src/evo/mnhftx.cpp

@@ -330,12 +330,12 @@ std::optional<CMNHFManager::Signals> CMNHFManager::GetFromCache(const CBlockInde
 
 void CMNHFManager::AddToCache(const Signals& signals, const CBlockIndex* const pindex)
 {
+    assert(pindex != nullptr);
     const uint256& blockHash = pindex->GetBlockHash();
     {
         LOCK(cs_cache);
         mnhfCache.insert(blockHash, signals);
     }
-    assert(pindex != nullptr);
     {
         LOCK(cs_cache);
         if (ThresholdState::ACTIVE != v20_activation.State(pindex->pprev, Params().GetConsensus(), Consensus::DEPLOYMENT_V20)) return;

src/governance/governance.cpp

@@ -367,11 +367,6 @@ void CGovernanceManager::UpdateCachesAndClean()
     while (it != mapObjects.end()) {
         CGovernanceObject* pObj = &((*it).second);
 
-        if (!pObj) {
-            ++it;
-            continue;
-        }
-
         uint256 nHash = it->first;
         std::string strHash = nHash.ToString();
 

src/llmq/signing.cpp

@@ -1020,7 +1020,7 @@ CQuorumCPtr CSigningManager::SelectQuorumForSigning(const Consensus::LLMQParams&
         //Extract last 64 bits of selectionHash
         uint64_t b = selectionHash.GetUint64(3);
         //Take last n bits of b
-        uint64_t signer = (((1 << n) - 1) & (b >> (64 - n - 1)));
+        uint64_t signer = (((1ull << n) - 1) & (b >> (64 - n - 1)));
 
         if (signer > quorums.size()) {
             return nullptr;

src/net.cpp

@@ -3291,8 +3291,7 @@ void CExplicitNetCleanup::callCleanup()
 {
     // Explicit call to destructor of CNetCleanup because it's not implicitly called
     // when the wallet is restarted from within the wallet itself.
-    CNetCleanup *tmp = new CNetCleanup();
-    delete tmp; // Stroustrup's gonna kill me for that
+    CNetCleanup tmp;
 }
 
 void CConnman::Interrupt()
@@ -3955,7 +3954,6 @@ void CConnman::PushMessage(CNode* pnode, CSerializedNetMsg&& msg)
     statsClient.count("bandwidth.message." + SanitizeString(msg.command.c_str()) + ".bytesSent", nTotalSize, 1.0f);
     statsClient.inc("message.sent." + SanitizeString(msg.command.c_str()), 1.0f);
 
-    size_t nBytesSent = 0;
     {
         LOCK(pnode->cs_vSend);
         bool hasPendingData = !pnode->vSendMsg.empty();
@@ -3986,8 +3984,6 @@ void CConnman::PushMessage(CNode* pnode, CSerializedNetMsg&& msg)
         if (!hasPendingData && wakeupSelectNeeded)
             WakeSelect();
     }
-    if (nBytesSent)
-        RecordBytesSent(nBytesSent);
 }
 
 bool CConnman::ForNode(const CService& addr, std::function<bool(const CNode* pnode)> cond, std::function<bool(CNode* pnode)> func)

src/qt/coincontroldialog.cpp

@@ -481,7 +481,6 @@ void CoinControlDialog::updateLabels(CCoinControl& m_coin_control, WalletModel *
     unsigned int nBytesInputs   = 0;
     unsigned int nQuantity      = 0;
     bool fUnselectedSpent{false};
-    bool fUnselectedNonMixed{false};
 
     std::vector<COutPoint> vCoinControl;
     m_coin_control.ListSelected(vCoinControl);
@@ -575,7 +574,7 @@ void CoinControlDialog::updateLabels(CCoinControl& m_coin_control, WalletModel *
 
     // actually update labels
     int nDisplayUnit = BitcoinUnits::DASH;
-    if (model && model->getOptionsModel())
+    if (model->getOptionsModel())
         nDisplayUnit = model->getOptionsModel()->getDisplayUnit();
 
     QLabel *l1 = dialog->findChild<QLabel *>("labelCoinControlQuantity");
@@ -639,10 +638,6 @@ void CoinControlDialog::updateLabels(CCoinControl& m_coin_control, WalletModel *
         QMessageBox::warning(dialog, "CoinControl",
             tr("Some coins were unselected because they were spent."),
             QMessageBox::Ok, QMessageBox::Ok);
-    } else if (fUnselectedNonMixed) {
-        QMessageBox::warning(dialog, "CoinControl",
-            tr("Some coins were unselected because they do not have enough mixing rounds."),
-            QMessageBox::Ok, QMessageBox::Ok);
     }
 }
 

src/qt/overviewpage.cpp

@@ -219,12 +219,10 @@ void OverviewPage::setBalance(const interfaces::WalletBalances& balances)
 
     updateCoinJoinProgress();
 
-    if (walletModel) {
-        int numISLocks = walletModel->getNumISLocks();
-        if(cachedNumISLocks != numISLocks) {
-            cachedNumISLocks = numISLocks;
-            ui->listTransactions->update();
-        }
+    int numISLocks = walletModel->getNumISLocks();
+    if(cachedNumISLocks != numISLocks) {
+        cachedNumISLocks = numISLocks;
+        ui->listTransactions->update();
     }
 }
 
@@ -638,7 +636,7 @@ void OverviewPage::toggleCoinJoin(){
         }
 
         // if wallet is locked, ask for a passphrase
-        if (walletModel && walletModel->getEncryptionStatus() == WalletModel::Locked)
+        if (walletModel->getEncryptionStatus() == WalletModel::Locked)
         {
             WalletModel::UnlockContext ctx(walletModel->requestUnlock(true));
             if(!ctx.isValid())