diff --git a/src/app/application.cpp b/src/app/application.cpp
index 8e097c8ba..da26777d3 100644
--- a/src/app/application.cpp
+++ b/src/app/application.cpp
@@ -127,7 +127,7 @@ Application::Application(const QString &id, int &argc, char **argv)
     setApplicationName("qBittorrent");
     validateCommandLineParameters();
 
-    QString profileDir = m_commandLineArgs.portableMode
+    const QString profileDir = m_commandLineArgs.portableMode
         ? QDir(QCoreApplication::applicationDirPath()).absoluteFilePath(DEFAULT_PORTABLE_MODE_PROFILE_DIR)
         : m_commandLineArgs.profileDir;
 
@@ -185,7 +185,7 @@ bool Application::isFileLoggerEnabled() const
     return settings()->loadValue(KEY_FILELOGGER_ENABLED, true).toBool();
 }
 
-void Application::setFileLoggerEnabled(bool value)
+void Application::setFileLoggerEnabled(const bool value)
 {
     if (value && !m_fileLogger)
         m_fileLogger = new FileLogger(fileLoggerPath(), isFileLoggerBackup(), fileLoggerMaxSize(), isFileLoggerDeleteOld(), fileLoggerAge(), static_cast<FileLogger::FileLogAgeType>(fileLoggerAgeType()));
@@ -212,7 +212,7 @@ bool Application::isFileLoggerBackup() const
     return settings()->loadValue(KEY_FILELOGGER_BACKUP, true).toBool();
 }
 
-void Application::setFileLoggerBackup(bool value)
+void Application::setFileLoggerBackup(const bool value)
 {
     if (m_fileLogger)
         m_fileLogger->setBackup(value);
@@ -224,7 +224,7 @@ bool Application::isFileLoggerDeleteOld() const
     return settings()->loadValue(KEY_FILELOGGER_DELETEOLD, true).toBool();
 }
 
-void Application::setFileLoggerDeleteOld(bool value)
+void Application::setFileLoggerDeleteOld(const bool value)
 {
     if (value && m_fileLogger)
         m_fileLogger->deleteOld(fileLoggerAge(), static_cast<FileLogger::FileLogAgeType>(fileLoggerAgeType()));
@@ -233,13 +233,13 @@ void Application::setFileLoggerDeleteOld(bool value)
 
 int Application::fileLoggerMaxSize() const
 {
-    int val = settings()->loadValue(KEY_FILELOGGER_MAXSIZEBYTES, DEFAULT_FILELOG_SIZE).toInt();
+    const int val = settings()->loadValue(KEY_FILELOGGER_MAXSIZEBYTES, DEFAULT_FILELOG_SIZE).toInt();
     return std::min(std::max(val, MIN_FILELOG_SIZE), MAX_FILELOG_SIZE);
 }
 
 void Application::setFileLoggerMaxSize(const int bytes)
 {
-    int clampedValue = std::min(std::max(bytes, MIN_FILELOG_SIZE), MAX_FILELOG_SIZE);
+    const int clampedValue = std::min(std::max(bytes, MIN_FILELOG_SIZE), MAX_FILELOG_SIZE);
     if (m_fileLogger)
         m_fileLogger->setMaxSize(clampedValue);
     settings()->storeValue(KEY_FILELOGGER_MAXSIZEBYTES, clampedValue);
@@ -247,7 +247,7 @@ void Application::setFileLoggerMaxSize(const int bytes)
 
 int Application::fileLoggerAge() const
 {
-    int val = settings()->loadValue(KEY_FILELOGGER_AGE, 1).toInt();
+    const int val = settings()->loadValue(KEY_FILELOGGER_AGE, 1).toInt();
     return std::min(std::max(val, 1), 365);
 }
 
@@ -258,7 +258,7 @@ void Application::setFileLoggerAge(const int value)
 
 int Application::fileLoggerAgeType() const
 {
-    int val = settings()->loadValue(KEY_FILELOGGER_AGETYPE, 1).toInt();
+    const int val = settings()->loadValue(KEY_FILELOGGER_AGETYPE, 1).toInt();
     return ((val < 0) || (val > 2)) ? 1 : val;
 }
 
@@ -269,7 +269,7 @@ void Application::setFileLoggerAgeType(const int value)
 
 void Application::processMessage(const QString &message)
 {
-    QStringList params = message.split(PARAMS_SEPARATOR, QString::SkipEmptyParts);
+    const QStringList params = message.split(PARAMS_SEPARATOR, QString::SkipEmptyParts);
     // If Application is not running (i.e., other
     // components are not ready) store params
     if (m_running)
@@ -572,7 +572,7 @@ int Application::exec(const QStringList &params)
 #ifdef Q_OS_WIN
 bool Application::isRunning()
 {
-    bool running = BaseApplication::isRunning();
+    const bool running = BaseApplication::isRunning();
     QSharedMemory *sharedMem = new QSharedMemory(id() + QLatin1String("-shared-memory-key"), this);
     if (!running) {
         // First instance creates shared memory and store PID
@@ -622,7 +622,7 @@ void Application::initializeTranslation()
 {
     Preferences *const pref = Preferences::instance();
     // Load translation
-    QString localeStr = pref->getLocale();
+    const QString localeStr = pref->getLocale();
 
     if (m_qtTranslator.load(QLatin1String("qtbase_") + localeStr, QLibraryInfo::location(QLibraryInfo::TranslationsPath)) ||
         m_qtTranslator.load(QLatin1String("qt_") + localeStr, QLibraryInfo::location(QLibraryInfo::TranslationsPath)))
diff --git a/src/app/application.h b/src/app/application.h
index 57e83e189..d6bca740c 100644
--- a/src/app/application.h
+++ b/src/app/application.h
@@ -99,11 +99,11 @@ public:
     bool isFileLoggerDeleteOld() const;
     void setFileLoggerDeleteOld(bool value);
     int fileLoggerMaxSize() const;
-    void setFileLoggerMaxSize(const int bytes);
+    void setFileLoggerMaxSize(int bytes);
     int fileLoggerAge() const;
-    void setFileLoggerAge(const int value);
+    void setFileLoggerAge(int value);
     int fileLoggerAgeType() const;
-    void setFileLoggerAgeType(const int value);
+    void setFileLoggerAgeType(int value);
 
 protected:
 #ifndef DISABLE_GUI
diff --git a/src/app/cmdoptions.cpp b/src/app/cmdoptions.cpp
index b0c87db38..47aa3aeae 100644
--- a/src/app/cmdoptions.cpp
+++ b/src/app/cmdoptions.cpp
@@ -276,7 +276,7 @@ namespace
 
         TriStateBool value(const QProcessEnvironment &env) const
         {
-            QString val = env.value(envVarName(), "-1");
+            const QString val = env.value(envVarName(), "-1");
 
             if (val.isEmpty()) {
                 return TriStateBool(m_defaultValue);
diff --git a/src/app/filelogger.cpp b/src/app/filelogger.cpp
index c16c9deb3..4a44f57f6 100644
--- a/src/app/filelogger.cpp
+++ b/src/app/filelogger.cpp
@@ -85,8 +85,8 @@ void FileLogger::changePath(const QString &newPath)
 
 void FileLogger::deleteOld(const int age, const FileLogAgeType ageType)
 {
-    QDateTime date = QDateTime::currentDateTime();
-    QDir dir(Utils::Fs::branchPath(m_path));
+    const QDateTime date = QDateTime::currentDateTime();
+    const QDir dir(Utils::Fs::branchPath(m_path));
 
     for (const QFileInfo &file : asConst(dir.entryInfoList(QStringList("qbittorrent.log.bak*"), QDir::Files | QDir::Writable, QDir::Time | QDir::Reversed))) {
         QDateTime modificationDate = file.lastModified();
@@ -111,7 +111,7 @@ void FileLogger::setBackup(bool value)
     m_backup = value;
 }
 
-void FileLogger::setMaxSize(int value)
+void FileLogger::setMaxSize(const int value)
 {
     m_maxSize = value;
 }
diff --git a/src/app/filelogger.h b/src/app/filelogger.h
index 4b7807f35..5eefb3d90 100644
--- a/src/app/filelogger.h
+++ b/src/app/filelogger.h
@@ -52,11 +52,11 @@ public:
         YEARS
     };
 
-    FileLogger(const QString &path, const bool backup, const int maxSize, const bool deleteOld, const int age, const FileLogAgeType ageType);
+    FileLogger(const QString &path, bool backup, int maxSize, bool deleteOld, int age, FileLogAgeType ageType);
     ~FileLogger();
 
     void changePath(const QString &newPath);
-    void deleteOld(const int age, const FileLogAgeType ageType);
+    void deleteOld(int age, FileLogAgeType ageType);
     void setBackup(bool value);
     void setMaxSize(int value);
 
diff --git a/src/app/main.cpp b/src/app/main.cpp
index caa5d1211..d8dc112a6 100644
--- a/src/app/main.cpp
+++ b/src/app/main.cpp
@@ -115,7 +115,7 @@ int main(int argc, char *argv[])
 
     try {
         // Create Application
-        QString appId = QLatin1String("qBittorrent-") + Utils::Misc::getUserIDString();
+        const QString appId = QLatin1String("qBittorrent-") + Utils::Misc::getUserIDString();
         QScopedPointer<Application> app(new Application(appId, argc, argv));
 
         const QBtCommandLineParameters params = app->commandLineArgs();
@@ -254,7 +254,7 @@ void reportToUser(const char *str)
 {
     const size_t strLen = strlen(str);
     if (write(STDERR_FILENO, str, strLen) < static_cast<ssize_t>(strLen)) {
-        auto dummy = write(STDOUT_FILENO, str, strLen);
+        const auto dummy = write(STDOUT_FILENO, str, strLen);
         Q_UNUSED(dummy);
     }
 }
@@ -304,7 +304,7 @@ void showSplashScreen()
 {
     QPixmap splashImg(":/icons/skin/splash.png");
     QPainter painter(&splashImg);
-    QString version = QBT_VERSION;
+    const QString version = QBT_VERSION;
     painter.setPen(QPen(Qt::white));
     painter.setFont(QFont("Arial", 22, QFont::Black));
     painter.drawText(224 - painter.fontMetrics().width(version), 270, version);
@@ -322,7 +322,7 @@ void displayVersion()
 
 void displayBadArgMessage(const QString &message)
 {
-    QString help = QObject::tr("Run application with -h option to read about command line parameters.");
+    const QString help = QObject::tr("Run application with -h option to read about command line parameters.");
 #ifdef Q_OS_WIN
     QMessageBox msgBox(QMessageBox::Critical, QObject::tr("Bad command line"),
                        message + QLatin1Char('\n') + help, QMessageBox::Ok);
@@ -350,7 +350,7 @@ bool userAgreesWithLegalNotice()
         + QObject::tr("Press %1 key to accept and continue...").arg("'y'") + '\n';
     printf("%s", qUtf8Printable(eula));
 
-    char ret = getchar(); // Read pressed key
+    const char ret = getchar(); // Read pressed key
     if ((ret == 'y') || (ret == 'Y')) {
         // Save the answer
         pref->setAcceptedLegal(true);
@@ -361,7 +361,7 @@ bool userAgreesWithLegalNotice()
     msgBox.setText(QObject::tr("qBittorrent is a file sharing program. When you run a torrent, its data will be made available to others by means of upload. Any content you share is your sole responsibility.\n\nNo further notices will be issued."));
     msgBox.setWindowTitle(QObject::tr("Legal notice"));
     msgBox.addButton(QObject::tr("Cancel"), QMessageBox::RejectRole);
-    QAbstractButton *agreeButton = msgBox.addButton(QObject::tr("I Agree"), QMessageBox::AcceptRole);
+    const QAbstractButton *agreeButton = msgBox.addButton(QObject::tr("I Agree"), QMessageBox::AcceptRole);
     msgBox.show(); // Need to be shown or to moveToCenter does not work
     msgBox.move(Utils::Misc::screenCenter(&msgBox));
     msgBox.exec();
diff --git a/src/base/bittorrent/private/bandwidthscheduler.cpp b/src/base/bittorrent/private/bandwidthscheduler.cpp
index b65cf62c3..308b3217e 100644
--- a/src/base/bittorrent/private/bandwidthscheduler.cpp
+++ b/src/base/bittorrent/private/bandwidthscheduler.cpp
@@ -93,7 +93,7 @@ bool BandwidthScheduler::isTimeForAlternative() const
 
 void BandwidthScheduler::onTimeout()
 {
-    bool alternative = isTimeForAlternative();
+    const bool alternative = isTimeForAlternative();
 
     if (alternative != m_lastAlternative) {
         m_lastAlternative = alternative;
diff --git a/src/base/bittorrent/private/filterparserthread.cpp b/src/base/bittorrent/private/filterparserthread.cpp
index 417d55c8d..3097e9642 100644
--- a/src/base/bittorrent/private/filterparserthread.cpp
+++ b/src/base/bittorrent/private/filterparserthread.cpp
@@ -50,7 +50,7 @@ namespace
             char *endptr;
             for (; *str; ++str) {
                 if (*str == '.') {
-                    long int extractedNum = strtol(octetStart, &endptr, 10);
+                    const long int extractedNum = strtol(octetStart, &endptr, 10);
                     if ((extractedNum >= 0L) && (extractedNum <= 255L))
                         m_buf[octetIndex++] = static_cast<unsigned char>(extractedNum);
                     else
@@ -66,7 +66,7 @@ namespace
             }
 
             if (str != octetStart) {
-                long int extractedNum = strtol(octetStart, &endptr, 10);
+                const long int extractedNum = strtol(octetStart, &endptr, 10);
                 if ((extractedNum >= 0L) && (extractedNum <= 255L))
                     m_buf[octetIndex] = static_cast<unsigned char>(strtol(octetStart, &endptr, 10));
                 else
@@ -146,7 +146,7 @@ int FilterParserThread::parseDATFilterFile()
         bytesRead = file.read(buffer.data() + offset, BUFFER_SIZE - offset - 1);
         if (bytesRead < 0)
             break;
-        int dataSize = bytesRead + offset;
+        const int dataSize = bytesRead + offset;
         if ((bytesRead == 0) && (dataSize == 0))
             break;
 
@@ -190,7 +190,7 @@ int FilterParserThread::parseDATFilterFile()
             // Each line should follow this format:
             // 001.009.096.105 - 001.009.096.105 , 000 , Some organization
             // The 3rd entry is access level and if above 127 the IP range isn't blocked.
-            int firstComma = findAndNullDelimiter(buffer.data(), ',', start, endOfLine);
+            const int firstComma = findAndNullDelimiter(buffer.data(), ',', start, endOfLine);
             if (firstComma != -1)
                 findAndNullDelimiter(buffer.data(), ',', firstComma + 1, endOfLine);
 
@@ -206,8 +206,8 @@ int FilterParserThread::parseDATFilterFile()
             }
 
             // IP Range should be split by a dash
-            int endOfIPRange = ((firstComma == -1) ? (endOfLine - 1) : (firstComma - 1));
-            int delimIP = findAndNullDelimiter(buffer.data(), '-', start, endOfIPRange);
+            const int endOfIPRange = ((firstComma == -1) ? (endOfLine - 1) : (firstComma - 1));
+            const int delimIP = findAndNullDelimiter(buffer.data(), '-', start, endOfIPRange);
             if (delimIP == -1) {
                 ++parseErrorCount;
                 addLog(tr("IP filter line %1 is malformed.").arg(nbLine));
@@ -294,7 +294,7 @@ int FilterParserThread::parseP2PFilterFile()
         bytesRead = file.read(buffer.data() + offset, BUFFER_SIZE - offset - 1);
         if (bytesRead < 0)
             break;
-        int dataSize = bytesRead + offset;
+        const int dataSize = bytesRead + offset;
         if ((bytesRead == 0) && (dataSize == 0))
             break;
 
@@ -338,7 +338,7 @@ int FilterParserThread::parseP2PFilterFile()
             // Each line should follow this format:
             // Some organization:1.0.0.0-1.255.255.255
             // The "Some organization" part might contain a ':' char itself so we find the last occurrence
-            int partsDelimiter = findAndNullDelimiter(buffer.data(), ':', start, endOfLine, true);
+            const int partsDelimiter = findAndNullDelimiter(buffer.data(), ':', start, endOfLine, true);
             if (partsDelimiter == -1) {
                 ++parseErrorCount;
                 addLog(tr("IP filter line %1 is malformed.").arg(nbLine));
@@ -347,7 +347,7 @@ int FilterParserThread::parseP2PFilterFile()
             }
 
             // IP Range should be split by a dash
-            int delimIP = findAndNullDelimiter(buffer.data(), '-', partsDelimiter + 1, endOfLine);
+            const int delimIP = findAndNullDelimiter(buffer.data(), '-', partsDelimiter + 1, endOfLine);
             if (delimIP == -1) {
                 ++parseErrorCount;
                 addLog(tr("IP filter line %1 is malformed.").arg(nbLine));
@@ -404,7 +404,7 @@ int FilterParserThread::parseP2PFilterFile()
     return ruleCount;
 }
 
-int FilterParserThread::getlineInStream(QDataStream &stream, std::string &name, char delim)
+int FilterParserThread::getlineInStream(QDataStream &stream, std::string &name, const char delim)
 {
     char c;
     int totalRead = 0;
@@ -465,8 +465,8 @@ int FilterParserThread::parseP2BFilterFile()
             // Network byte order to Host byte order
             // asio address_v4 constructor expects it
             // that way
-            libt::address_v4 first(ntohl(start));
-            libt::address_v4 last(ntohl(end));
+            const libt::address_v4 first(ntohl(start));
+            const libt::address_v4 last(ntohl(end));
             // Apply to bittorrent session
             try {
                 m_filter.add_rule(first, last, libt::ip_filter::blocked);
@@ -515,8 +515,8 @@ int FilterParserThread::parseP2BFilterFile()
             // Network byte order to Host byte order
             // asio address_v4 constructor expects it
             // that way
-            libt::address_v4 first(ntohl(start));
-            libt::address_v4 last(ntohl(end));
+            const libt::address_v4 first(ntohl(start));
+            const libt::address_v4 last(ntohl(end));
             // Apply to bittorrent session
             try {
                 m_filter.add_rule(first, last, libt::ip_filter::blocked);
@@ -588,7 +588,7 @@ void FilterParserThread::run()
     qDebug("IP Filter thread: finished parsing, filter applied");
 }
 
-int FilterParserThread::findAndNullDelimiter(char *const data, char delimiter, int start, int end, bool reverse)
+int FilterParserThread::findAndNullDelimiter(char *const data, const char delimiter, const int start, const int end, const bool reverse)
 {
     if (!reverse) {
         for (int i = start; i <= end; ++i) {
@@ -610,7 +610,7 @@ int FilterParserThread::findAndNullDelimiter(char *const data, char delimiter, i
     return -1;
 }
 
-int FilterParserThread::trim(char *const data, int start, int end)
+int FilterParserThread::trim(char *const data, const int start, const int end)
 {
     if (start >= end) return start;
     int newStart = start;
diff --git a/src/base/bittorrent/private/speedmonitor.cpp b/src/base/bittorrent/private/speedmonitor.cpp
index 096f9b883..96fbb96d4 100644
--- a/src/base/bittorrent/private/speedmonitor.cpp
+++ b/src/base/bittorrent/private/speedmonitor.cpp
@@ -49,7 +49,7 @@ SpeedSampleAvg SpeedMonitor::average() const
     if (m_speedSamples.empty())
         return SpeedSampleAvg();
 
-    qreal k = qreal(1.) / m_speedSamples.size();
+    const qreal k = qreal(1.) / m_speedSamples.size();
     return SpeedSampleAvg(m_sum.download * k, m_sum.upload * k);
 }
 
diff --git a/src/base/bittorrent/private/statistics.cpp b/src/base/bittorrent/private/statistics.cpp
index 23abc8351..f11897c21 100644
--- a/src/base/bittorrent/private/statistics.cpp
+++ b/src/base/bittorrent/private/statistics.cpp
@@ -60,7 +60,7 @@ void Statistics::gather()
 
 void Statistics::save() const
 {
-    qint64 now = QDateTime::currentMSecsSinceEpoch();
+    const qint64 now = QDateTime::currentMSecsSinceEpoch();
 
     if (!m_dirty || ((now - m_lastWrite) < SAVE_INTERVAL))
         return;
@@ -76,8 +76,8 @@ void Statistics::save() const
 
 void Statistics::load()
 {
-    SettingsPtr s = Profile::instance().applicationSettings(QLatin1String("qBittorrent-data"));
-    QVariantHash v = s->value("Stats/AllStats").toHash();
+    const SettingsPtr s = Profile::instance().applicationSettings(QLatin1String("qBittorrent-data"));
+    const QVariantHash v = s->value("Stats/AllStats").toHash();
 
     m_alltimeDL = v["AlltimeDL"].toULongLong();
     m_alltimeUL = v["AlltimeUL"].toULongLong();
diff --git a/src/base/bittorrent/session.cpp b/src/base/bittorrent/session.cpp
index 4799be686..8d93d313c 100644
--- a/src/base/bittorrent/session.cpp
+++ b/src/base/bittorrent/session.cpp
@@ -520,7 +520,7 @@ bool Session::isLSDEnabled() const
     return m_isLSDEnabled;
 }
 
-void Session::setLSDEnabled(bool enabled)
+void Session::setLSDEnabled(const bool enabled)
 {
     if (enabled != m_isLSDEnabled) {
         m_isLSDEnabled = enabled;
@@ -536,7 +536,7 @@ bool Session::isPeXEnabled() const
     return m_isPeXEnabled;
 }
 
-void Session::setPeXEnabled(bool enabled)
+void Session::setPeXEnabled(const bool enabled)
 {
     m_isPeXEnabled = enabled;
     if (m_wasPexEnabled != enabled)
@@ -548,7 +548,7 @@ bool Session::isTempPathEnabled() const
     return m_isTempPathEnabled;
 }
 
-void Session::setTempPathEnabled(bool enabled)
+void Session::setTempPathEnabled(const bool enabled)
 {
     if (enabled != isTempPathEnabled()) {
         m_isTempPathEnabled = enabled;
@@ -562,7 +562,7 @@ bool Session::isAppendExtensionEnabled() const
     return m_isAppendExtensionEnabled;
 }
 
-void Session::setAppendExtensionEnabled(bool enabled)
+void Session::setAppendExtensionEnabled(const bool enabled)
 {
     if (isAppendExtensionEnabled() != enabled) {
         // append or remove .!qB extension for incomplete files
@@ -578,7 +578,7 @@ uint Session::refreshInterval() const
     return m_refreshInterval;
 }
 
-void Session::setRefreshInterval(uint value)
+void Session::setRefreshInterval(const uint value)
 {
     if (value != refreshInterval()) {
         m_refreshTimer->setInterval(value);
@@ -591,7 +591,7 @@ bool Session::isPreallocationEnabled() const
     return m_isPreallocationEnabled;
 }
 
-void Session::setPreallocationEnabled(bool enabled)
+void Session::setPreallocationEnabled(const bool enabled)
 {
     m_isPreallocationEnabled = enabled;
 }
@@ -674,7 +674,7 @@ const QStringMap &Session::categories() const
 
 QString Session::categorySavePath(const QString &categoryName) const
 {
-    QString basePath = m_defaultSavePath;
+    const QString basePath = m_defaultSavePath;
     if (categoryName.isEmpty()) return basePath;
 
     QString path = m_categories.value(categoryName);
@@ -768,7 +768,7 @@ bool Session::isSubcategoriesEnabled() const
     return m_isSubcategoriesEnabled;
 }
 
-void Session::setSubcategoriesEnabled(bool value)
+void Session::setSubcategoriesEnabled(const bool value)
 {
     if (isSubcategoriesEnabled() == value) return;
 
@@ -833,7 +833,7 @@ bool Session::isAutoTMMDisabledByDefault() const
     return m_isAutoTMMDisabledByDefault;
 }
 
-void Session::setAutoTMMDisabledByDefault(bool value)
+void Session::setAutoTMMDisabledByDefault(const bool value)
 {
     m_isAutoTMMDisabledByDefault = value;
 }
@@ -843,7 +843,7 @@ bool Session::isDisableAutoTMMWhenCategoryChanged() const
     return m_isDisableAutoTMMWhenCategoryChanged;
 }
 
-void Session::setDisableAutoTMMWhenCategoryChanged(bool value)
+void Session::setDisableAutoTMMWhenCategoryChanged(const bool value)
 {
     m_isDisableAutoTMMWhenCategoryChanged = value;
 }
@@ -853,7 +853,7 @@ bool Session::isDisableAutoTMMWhenDefaultSavePathChanged() const
     return m_isDisableAutoTMMWhenDefaultSavePathChanged;
 }
 
-void Session::setDisableAutoTMMWhenDefaultSavePathChanged(bool value)
+void Session::setDisableAutoTMMWhenDefaultSavePathChanged(const bool value)
 {
     m_isDisableAutoTMMWhenDefaultSavePathChanged = value;
 }
@@ -863,7 +863,7 @@ bool Session::isDisableAutoTMMWhenCategorySavePathChanged() const
     return m_isDisableAutoTMMWhenCategorySavePathChanged;
 }
 
-void Session::setDisableAutoTMMWhenCategorySavePathChanged(bool value)
+void Session::setDisableAutoTMMWhenCategorySavePathChanged(const bool value)
 {
     m_isDisableAutoTMMWhenCategorySavePathChanged = value;
 }
@@ -873,7 +873,7 @@ bool Session::isAddTorrentPaused() const
     return m_isAddTorrentPaused;
 }
 
-void Session::setAddTorrentPaused(bool value)
+void Session::setAddTorrentPaused(const bool value)
 {
     m_isAddTorrentPaused = value;
 }
@@ -883,7 +883,7 @@ bool Session::isTrackerEnabled() const
     return m_isTrackerEnabled;
 }
 
-void Session::setTrackerEnabled(bool enabled)
+void Session::setTrackerEnabled(const bool enabled)
 {
     if (isTrackerEnabled() != enabled) {
         enableTracker(enabled);
@@ -1011,7 +1011,7 @@ void Session::processBannedIPs(libt::ip_filter &filter)
     // First, import current filter
     for (const QString &ip : asConst(m_bannedIPs.value())) {
         boost::system::error_code ec;
-        libt::address addr = libt::address::from_string(ip.toLatin1().constData(), ec);
+        const libt::address addr = libt::address::from_string(ip.toLatin1().constData(), ec);
         Q_ASSERT(!ec);
         if (!ec)
             filter.add_rule(addr, addr, libt::ip_filter::blocked);
@@ -1021,8 +1021,8 @@ void Session::processBannedIPs(libt::ip_filter &filter)
 void Session::adjustLimits(libt::settings_pack &settingsPack)
 {
     // Internally increase the queue limits to ensure that the magnet is started
-    int maxDownloads = maxActiveDownloads();
-    int maxActive = maxActiveTorrents();
+    const int maxDownloads = maxActiveDownloads();
+    const int maxActive = maxActiveTorrents();
 
     settingsPack.set_int(libt::settings_pack::active_downloads
                          , maxDownloads > -1 ? maxDownloads + m_extraLimit : maxDownloads);
@@ -1125,7 +1125,7 @@ void Session::configure(libtorrent::settings_pack &settingsPack)
 
     if (m_listenInterfaceChanged) {
         const ushort port = this->port();
-        std::pair<int, int> ports(port, port);
+        const std::pair<int, int> ports(port, port);
         settingsPack.set_int(libt::settings_pack::max_retry_port_bind, ports.second - ports.first);
         for (QString ip : getListeningIPs()) {
             libt::error_code ec;
@@ -1143,7 +1143,7 @@ void Session::configure(libtorrent::settings_pack &settingsPack)
                 break;
             }
 
-            libt::address addr = libt::address::from_string(ip.toLatin1().constData(), ec);
+            const libt::address addr = libt::address::from_string(ip.toLatin1().constData(), ec);
             if (!ec) {
                 interfacesStr = std::string((addr.is_v6() ? QString("[%1]:%2") : QString("%1:%2"))
                                             .arg(ip).arg(port).toLatin1().constData());
@@ -1164,7 +1164,7 @@ void Session::configure(libtorrent::settings_pack &settingsPack)
         // the interface's Luid and not the GUID.
         // Libtorrent expects GUIDs for the 'outgoing_interfaces' setting.
         if (!networkInterface().isEmpty()) {
-            QString guid = convertIfaceNameToGuid(networkInterface());
+            const QString guid = convertIfaceNameToGuid(networkInterface());
             if (!guid.isEmpty()) {
                 settingsPack.set_str(libt::settings_pack::outgoing_interfaces, guid.toStdString());
             }
@@ -1199,8 +1199,8 @@ void Session::configure(libtorrent::settings_pack &settingsPack)
         settingsPack.set_int(libt::settings_pack::in_enc_policy, libt::settings_pack::pe_disabled);
     }
 
-    auto proxyManager = Net::ProxyConfigurationManager::instance();
-    Net::ProxyConfiguration proxyConfig = proxyManager->proxyConfiguration();
+    const auto proxyManager = Net::ProxyConfigurationManager::instance();
+    const Net::ProxyConfiguration proxyConfig = proxyManager->proxyConfiguration();
     if (m_useProxy || (proxyConfig.type != Net::ProxyType::None)) {
         if (proxyConfig.type != Net::ProxyType::None) {
             settingsPack.set_str(libt::settings_pack::proxy_hostname, proxyConfig.ip.toStdString());
@@ -1444,7 +1444,7 @@ void Session::configurePeerClasses()
     m_nativeSession->set_peer_class_type_filter(peerClassTypeFilter);
 }
 
-void Session::enableTracker(bool enable)
+void Session::enableTracker(const bool enable)
 {
     Logger *const logger = Logger::instance();
 
@@ -1596,7 +1596,7 @@ void Session::banIP(const QString &ip)
     if (!bannedIPs.contains(ip)) {
         libt::ip_filter filter = m_nativeSession->get_ip_filter();
         boost::system::error_code ec;
-        libt::address addr = libt::address::from_string(ip.toLatin1().constData(), ec);
+        const libt::address addr = libt::address::from_string(ip.toLatin1().constData(), ec);
         Q_ASSERT(!ec);
         if (ec) return;
         filter.add_rule(addr, addr, libt::ip_filter::blocked);
@@ -1610,7 +1610,7 @@ void Session::banIP(const QString &ip)
 
 // Delete a torrent from the session, given its hash
 // deleteLocalFiles = true means that the torrent will be removed from the hard-drive too
-bool Session::deleteTorrent(const QString &hash, bool deleteLocalFiles)
+bool Session::deleteTorrent(const QString &hash, const bool deleteLocalFiles)
 {
     TorrentHandle *const torrent = m_torrents.take(hash);
     if (!torrent) return false;
@@ -1620,7 +1620,7 @@ bool Session::deleteTorrent(const QString &hash, bool deleteLocalFiles)
 
     // Remove it from session
     if (deleteLocalFiles) {
-        QString rootPath = torrent->rootPath(true);
+        const QString rootPath = torrent->rootPath(true);
         if (!rootPath.isEmpty())
             // torrent with root folder
             m_removingTorrents[torrent->hash()] = {torrent->name(), rootPath, deleteLocalFiles};
@@ -1648,7 +1648,7 @@ bool Session::deleteTorrent(const QString &hash, bool deleteLocalFiles)
     }
 
     // Remove it from torrent resume directory
-    QDir resumeDataDir(m_resumeFolderPath);
+    const QDir resumeDataDir(m_resumeFolderPath);
     QStringList filters;
     filters << QString("%1.*").arg(torrent->hash());
     const QStringList files = resumeDataDir.entryList(filters, QDir::Files, QDir::Unsorted);
@@ -1665,7 +1665,7 @@ bool Session::cancelLoadMetadata(const InfoHash &hash)
     if (!m_loadedMetadata.contains(hash)) return false;
 
     m_loadedMetadata.remove(hash);
-    libt::torrent_handle torrent = m_nativeSession->find_torrent(hash);
+    const libt::torrent_handle torrent = m_nativeSession->find_torrent(hash);
     if (!torrent.is_valid()) return false;
 
     if (!torrent.status(0).has_metadata) {
@@ -1795,7 +1795,7 @@ bool Session::addTorrent(const QString &source, const AddTorrentParams &params)
     if (Net::DownloadManager::hasSupportedScheme(source)) {
         LogMsg(tr("Downloading '%1', please wait...", "e.g: Downloading 'xxx.torrent', please wait...").arg(source));
         // Launch downloader
-        Net::DownloadHandler *handler =
+        const Net::DownloadHandler *handler =
                 Net::DownloadManager::instance()->download(Net::DownloadRequest(source).limit(10485760 /* 10MB */).handleRedirectToMagnet(true));
         connect(handler, static_cast<void (Net::DownloadHandler::*)(const QString &, const QByteArray &)>(&Net::DownloadHandler::downloadFinished)
                 , this, &Session::handleDownloadFinished);
@@ -1999,8 +1999,8 @@ bool Session::loadMetadata(const MagnetUri &magnetUri)
 {
     if (!magnetUri.isValid()) return false;
 
-    InfoHash hash = magnetUri.hash();
-    QString name = magnetUri.name();
+    const InfoHash hash = magnetUri.hash();
+    const QString name = magnetUri.name();
 
     // We should not add torrent if it's already
     // processed or adding to session
@@ -2052,11 +2052,11 @@ void Session::exportTorrentFile(TorrentHandle *const torrent, TorrentExportFolde
     Q_ASSERT(((folder == TorrentExportFolder::Regular) && !torrentExportDirectory().isEmpty()) ||
              ((folder == TorrentExportFolder::Finished) && !finishedTorrentExportDirectory().isEmpty()));
 
-    QString validName = Utils::Fs::toValidFileSystemName(torrent->name());
-    QString torrentFilename = QString("%1.torrent").arg(torrent->hash());
+    const QString validName = Utils::Fs::toValidFileSystemName(torrent->name());
+    const QString torrentFilename = QString("%1.torrent").arg(torrent->hash());
     QString torrentExportFilename = QString("%1.torrent").arg(validName);
-    QString torrentPath = QDir(m_resumeFolderPath).absoluteFilePath(torrentFilename);
-    QDir exportPath(folder == TorrentExportFolder::Regular ? torrentExportDirectory() : finishedTorrentExportDirectory());
+    const QString torrentPath = QDir(m_resumeFolderPath).absoluteFilePath(torrentFilename);
+    const QDir exportPath(folder == TorrentExportFolder::Regular ? torrentExportDirectory() : finishedTorrentExportDirectory());
     if (exportPath.exists() || exportPath.mkpath(exportPath.absolutePath())) {
         QString newTorrentPath = exportPath.absoluteFilePath(torrentExportFilename);
         int counter = 0;
@@ -2071,7 +2071,7 @@ void Session::exportTorrentFile(TorrentHandle *const torrent, TorrentExportFolde
     }
 }
 
-void Session::generateResumeData(bool final)
+void Session::generateResumeData(const bool final)
 {
     for (TorrentHandle *const torrent : asConst(m_torrents)) {
         if (!torrent->isValid()) continue;
@@ -2406,7 +2406,7 @@ bool Session::isBandwidthSchedulerEnabled() const
     return m_isBandwidthSchedulerEnabled;
 }
 
-void Session::setBandwidthSchedulerEnabled(bool enabled)
+void Session::setBandwidthSchedulerEnabled(const bool enabled)
 {
     if (enabled != isBandwidthSchedulerEnabled()) {
         m_isBandwidthSchedulerEnabled = enabled;
@@ -2446,7 +2446,7 @@ int Session::port() const
     return m_port;
 }
 
-void Session::setPort(int port)
+void Session::setPort(const int port)
 {
     if (port != this->port()) {
         m_port = port;
@@ -2459,7 +2459,7 @@ bool Session::useRandomPort() const
     return m_useRandomPort;
 }
 
-void Session::setUseRandomPort(bool value)
+void Session::setUseRandomPort(const bool value)
 {
     m_useRandomPort = value;
 }
@@ -2505,7 +2505,7 @@ bool Session::isIPv6Enabled() const
     return m_isIPv6Enabled;
 }
 
-void Session::setIPv6Enabled(bool enabled)
+void Session::setIPv6Enabled(const bool enabled)
 {
     if (enabled != isIPv6Enabled()) {
         m_isIPv6Enabled = enabled;
@@ -2518,7 +2518,7 @@ int Session::encryption() const
     return m_encryption;
 }
 
-void Session::setEncryption(int state)
+void Session::setEncryption(const int state)
 {
     if (state != encryption()) {
         m_encryption = state;
@@ -2535,7 +2535,7 @@ bool Session::isForceProxyEnabled() const
     return m_isForceProxyEnabled;
 }
 
-void Session::setForceProxyEnabled(bool enabled)
+void Session::setForceProxyEnabled(const bool enabled)
 {
     if (enabled != isForceProxyEnabled()) {
         m_isForceProxyEnabled = enabled;
@@ -2548,7 +2548,7 @@ bool Session::isProxyPeerConnectionsEnabled() const
     return m_isProxyPeerConnectionsEnabled;
 }
 
-void Session::setProxyPeerConnectionsEnabled(bool enabled)
+void Session::setProxyPeerConnectionsEnabled(const bool enabled)
 {
     if (enabled != isProxyPeerConnectionsEnabled()) {
         m_isProxyPeerConnectionsEnabled = enabled;
@@ -2561,7 +2561,7 @@ ChokingAlgorithm Session::chokingAlgorithm() const
     return m_chokingAlgorithm;
 }
 
-void Session::setChokingAlgorithm(ChokingAlgorithm mode)
+void Session::setChokingAlgorithm(const ChokingAlgorithm mode)
 {
     if (mode == m_chokingAlgorithm) return;
 
@@ -2574,7 +2574,7 @@ SeedChokingAlgorithm Session::seedChokingAlgorithm() const
     return m_seedChokingAlgorithm;
 }
 
-void Session::setSeedChokingAlgorithm(SeedChokingAlgorithm mode)
+void Session::setSeedChokingAlgorithm(const SeedChokingAlgorithm mode)
 {
     if (mode == m_seedChokingAlgorithm) return;
 
@@ -2587,7 +2587,7 @@ bool Session::isAddTrackersEnabled() const
     return m_isAddTrackersEnabled;
 }
 
-void Session::setAddTrackersEnabled(bool enabled)
+void Session::setAddTrackersEnabled(const bool enabled)
 {
     m_isAddTrackersEnabled = enabled;
 }
@@ -2610,7 +2610,7 @@ bool Session::isIPFilteringEnabled() const
     return m_isIPFilteringEnabled;
 }
 
-void Session::setIPFilteringEnabled(bool enabled)
+void Session::setIPFilteringEnabled(const bool enabled)
 {
     if (enabled != m_isIPFilteringEnabled) {
         m_isIPFilteringEnabled = enabled;
@@ -2722,7 +2722,7 @@ bool Session::announceToAllTrackers() const
     return m_announceToAllTrackers;
 }
 
-void Session::setAnnounceToAllTrackers(bool val)
+void Session::setAnnounceToAllTrackers(const bool val)
 {
     if (val != m_announceToAllTrackers) {
         m_announceToAllTrackers = val;
@@ -2735,7 +2735,7 @@ bool Session::announceToAllTiers() const
     return m_announceToAllTiers;
 }
 
-void Session::setAnnounceToAllTiers(bool val)
+void Session::setAnnounceToAllTiers(const bool val)
 {
     if (val != m_announceToAllTiers) {
         m_announceToAllTiers = val;
@@ -2806,7 +2806,7 @@ int Session::diskCacheTTL() const
     return m_diskCacheTTL;
 }
 
-void Session::setDiskCacheTTL(int ttl)
+void Session::setDiskCacheTTL(const int ttl)
 {
     if (ttl != m_diskCacheTTL) {
         m_diskCacheTTL = ttl;
@@ -2819,7 +2819,7 @@ bool Session::useOSCache() const
     return m_useOSCache;
 }
 
-void Session::setUseOSCache(bool use)
+void Session::setUseOSCache(const bool use)
 {
     if (use != m_useOSCache) {
         m_useOSCache = use;
@@ -2832,7 +2832,7 @@ bool Session::isGuidedReadCacheEnabled() const
     return m_guidedReadCacheEnabled;
 }
 
-void Session::setGuidedReadCacheEnabled(bool enabled)
+void Session::setGuidedReadCacheEnabled(const bool enabled)
 {
     if (enabled == m_guidedReadCacheEnabled) return;
 
@@ -2845,7 +2845,7 @@ bool Session::isCoalesceReadWriteEnabled() const
     return m_coalesceReadWriteEnabled;
 }
 
-void Session::setCoalesceReadWriteEnabled(bool enabled)
+void Session::setCoalesceReadWriteEnabled(const bool enabled)
 {
     if (enabled == m_coalesceReadWriteEnabled) return;
 
@@ -2858,7 +2858,7 @@ bool Session::isSuggestModeEnabled() const
     return m_isSuggestMode;
 }
 
-void Session::setSuggestMode(bool mode)
+void Session::setSuggestMode(const bool mode)
 {
     if (mode == m_isSuggestMode) return;
 
@@ -2871,7 +2871,7 @@ int Session::sendBufferWatermark() const
     return m_sendBufferWatermark;
 }
 
-void Session::setSendBufferWatermark(int value)
+void Session::setSendBufferWatermark(const int value)
 {
     if (value == m_sendBufferWatermark) return;
 
@@ -2884,7 +2884,7 @@ int Session::sendBufferLowWatermark() const
     return m_sendBufferLowWatermark;
 }
 
-void Session::setSendBufferLowWatermark(int value)
+void Session::setSendBufferLowWatermark(const int value)
 {
     if (value == m_sendBufferLowWatermark) return;
 
@@ -2897,7 +2897,7 @@ int Session::sendBufferWatermarkFactor() const
     return m_sendBufferWatermarkFactor;
 }
 
-void Session::setSendBufferWatermarkFactor(int value)
+void Session::setSendBufferWatermarkFactor(const int value)
 {
     if (value == m_sendBufferWatermarkFactor) return;
 
@@ -2910,7 +2910,7 @@ bool Session::isAnonymousModeEnabled() const
     return m_isAnonymousModeEnabled;
 }
 
-void Session::setAnonymousModeEnabled(bool enabled)
+void Session::setAnonymousModeEnabled(const bool enabled)
 {
     if (enabled != m_isAnonymousModeEnabled) {
         m_isAnonymousModeEnabled = enabled;
@@ -2926,7 +2926,7 @@ bool Session::isQueueingSystemEnabled() const
     return m_isQueueingEnabled;
 }
 
-void Session::setQueueingSystemEnabled(bool enabled)
+void Session::setQueueingSystemEnabled(const bool enabled)
 {
     if (enabled != m_isQueueingEnabled) {
         m_isQueueingEnabled = enabled;
@@ -2986,7 +2986,7 @@ bool Session::ignoreSlowTorrentsForQueueing() const
     return m_ignoreSlowTorrentsForQueueing;
 }
 
-void Session::setIgnoreSlowTorrentsForQueueing(bool ignore)
+void Session::setIgnoreSlowTorrentsForQueueing(const bool ignore)
 {
     if (ignore != m_ignoreSlowTorrentsForQueueing) {
         m_ignoreSlowTorrentsForQueueing = ignore;
@@ -2999,7 +2999,7 @@ int Session::downloadRateForSlowTorrents() const
     return m_downloadRateForSlowTorrents;
 }
 
-void Session::setDownloadRateForSlowTorrents(int rateInKibiBytes)
+void Session::setDownloadRateForSlowTorrents(const int rateInKibiBytes)
 {
     if (rateInKibiBytes == m_downloadRateForSlowTorrents)
         return;
@@ -3013,7 +3013,7 @@ int Session::uploadRateForSlowTorrents() const
     return m_uploadRateForSlowTorrents;
 }
 
-void Session::setUploadRateForSlowTorrents(int rateInKibiBytes)
+void Session::setUploadRateForSlowTorrents(const int rateInKibiBytes)
 {
     if (rateInKibiBytes == m_uploadRateForSlowTorrents)
         return;
@@ -3027,7 +3027,7 @@ int Session::slowTorrentsInactivityTimer() const
     return m_slowTorrentsInactivityTimer;
 }
 
-void Session::setSlowTorrentsInactivityTimer(int timeInSeconds)
+void Session::setSlowTorrentsInactivityTimer(const int timeInSeconds)
 {
     if (timeInSeconds == m_slowTorrentsInactivityTimer)
         return;
@@ -3041,7 +3041,7 @@ int Session::outgoingPortsMin() const
     return m_outgoingPortsMin;
 }
 
-void Session::setOutgoingPortsMin(int min)
+void Session::setOutgoingPortsMin(const int min)
 {
     if (min != m_outgoingPortsMin) {
         m_outgoingPortsMin = min;
@@ -3054,7 +3054,7 @@ int Session::outgoingPortsMax() const
     return m_outgoingPortsMax;
 }
 
-void Session::setOutgoingPortsMax(int max)
+void Session::setOutgoingPortsMax(const int max)
 {
     if (max != m_outgoingPortsMax) {
         m_outgoingPortsMax = max;
@@ -3067,7 +3067,7 @@ bool Session::ignoreLimitsOnLAN() const
     return m_ignoreLimitsOnLAN;
 }
 
-void Session::setIgnoreLimitsOnLAN(bool ignore)
+void Session::setIgnoreLimitsOnLAN(const bool ignore)
 {
     if (ignore != m_ignoreLimitsOnLAN) {
         m_ignoreLimitsOnLAN = ignore;
@@ -3080,7 +3080,7 @@ bool Session::includeOverheadInLimits() const
     return m_includeOverheadInLimits;
 }
 
-void Session::setIncludeOverheadInLimits(bool include)
+void Session::setIncludeOverheadInLimits(const bool include)
 {
     if (include != m_includeOverheadInLimits) {
         m_includeOverheadInLimits = include;
@@ -3106,7 +3106,7 @@ bool Session::isSuperSeedingEnabled() const
     return m_isSuperSeedingEnabled;
 }
 
-void Session::setSuperSeedingEnabled(bool enabled)
+void Session::setSuperSeedingEnabled(const bool enabled)
 {
     if (enabled != m_isSuperSeedingEnabled) {
         m_isSuperSeedingEnabled = enabled;
@@ -3161,7 +3161,7 @@ BTProtocol Session::btProtocol() const
     return m_btProtocol;
 }
 
-void Session::setBTProtocol(BTProtocol protocol)
+void Session::setBTProtocol(const BTProtocol protocol)
 {
     if ((protocol < BTProtocol::Both) || (BTProtocol::UTP < protocol))
         return;
@@ -3177,7 +3177,7 @@ bool Session::isUTPRateLimited() const
     return m_isUTPRateLimited;
 }
 
-void Session::setUTPRateLimited(bool limited)
+void Session::setUTPRateLimited(const bool limited)
 {
     if (limited != m_isUTPRateLimited) {
         m_isUTPRateLimited = limited;
@@ -3190,7 +3190,7 @@ MixedModeAlgorithm Session::utpMixedMode() const
     return m_utpMixedMode;
 }
 
-void Session::setUtpMixedMode(MixedModeAlgorithm mode)
+void Session::setUtpMixedMode(const MixedModeAlgorithm mode)
 {
     if (mode == m_utpMixedMode) return;
 
@@ -3203,7 +3203,7 @@ bool Session::multiConnectionsPerIpEnabled() const
     return m_multiConnectionsPerIpEnabled;
 }
 
-void Session::setMultiConnectionsPerIpEnabled(bool enabled)
+void Session::setMultiConnectionsPerIpEnabled(const bool enabled)
 {
     if (enabled == m_multiConnectionsPerIpEnabled) return;
 
@@ -3216,7 +3216,7 @@ bool Session::isTrackerFilteringEnabled() const
     return m_isTrackerFilteringEnabled;
 }
 
-void Session::setTrackerFilteringEnabled(bool enabled)
+void Session::setTrackerFilteringEnabled(const bool enabled)
 {
     if (enabled != m_isTrackerFilteringEnabled) {
         m_isTrackerFilteringEnabled = enabled;
@@ -3234,7 +3234,7 @@ MaxRatioAction Session::maxRatioAction() const
     return static_cast<MaxRatioAction>(m_maxRatioAction.value());
 }
 
-void Session::setMaxRatioAction(MaxRatioAction act)
+void Session::setMaxRatioAction(const MaxRatioAction act)
 {
     m_maxRatioAction = static_cast<int>(act);
 }
@@ -3483,7 +3483,7 @@ bool Session::hasPerTorrentSeedingTimeLimit() const
 void Session::initResumeFolder()
 {
     m_resumeFolderPath = Utils::Fs::expandPathAbs(specialFolderLocation(SpecialFolder::Data) + RESUME_FOLDER);
-    QDir resumeFolderDir(m_resumeFolderPath);
+    const QDir resumeFolderDir(m_resumeFolderPath);
     if (resumeFolderDir.exists() || resumeFolderDir.mkpath(resumeFolderDir.absolutePath())) {
         m_resumeFolderLock.setFileName(resumeFolderDir.absoluteFilePath("session.lock"));
         if (!m_resumeFolderLock.open(QFile::WriteOnly)) {
@@ -3525,7 +3525,7 @@ void Session::disableIPFilter()
 {
     qDebug("Disabling IPFilter");
     if (m_filterParser) {
-        disconnect(m_filterParser.data(), 0, this, 0);
+        disconnect(m_filterParser.data(), nullptr, this, nullptr);
         delete m_filterParser;
     }
 
@@ -3591,7 +3591,7 @@ void Session::startUpTorrents()
     int resumedTorrentsCount = 0;
     const auto startupTorrent = [this, logger, &resumeDataDir, &resumedTorrentsCount](const TorrentResumeData &params)
     {
-        QString filePath = resumeDataDir.filePath(QString("%1.torrent").arg(params.hash));
+        const QString filePath = resumeDataDir.filePath(QString("%1.torrent").arg(params.hash));
         qDebug() << "Starting up torrent" << params.hash << "...";
         if (!addTorrent_impl(params.addTorrentData, params.magnetUri, TorrentInfo::loadFromFile(filePath), params.data))
             logger->addMessage(tr("Unable to resume torrent '%1'.", "e.g: Unable to resume torrent 'hash'.")
@@ -3712,7 +3712,7 @@ void Session::refresh()
     m_nativeSession->post_session_stats();
 }
 
-void Session::handleIPFilterParsed(int ruleCount)
+void Session::handleIPFilterParsed(const int ruleCount)
 {
     if (m_filterParser) {
         libt::ip_filter filter = m_filterParser->IPfilter();
@@ -3733,7 +3733,7 @@ void Session::handleIPFilterError()
     emit IPFilterParsed(true, 0);
 }
 
-void Session::getPendingAlerts(std::vector<libt::alert *> &out, ulong time)
+void Session::getPendingAlerts(std::vector<libt::alert *> &out, const ulong time)
 {
     Q_ASSERT(out.empty());
 
@@ -3747,7 +3747,7 @@ bool Session::isCreateTorrentSubfolder() const
     return m_isCreateTorrentSubfolder;
 }
 
-void Session::setCreateTorrentSubfolder(bool value)
+void Session::setCreateTorrentSubfolder(const bool value)
 {
     m_isCreateTorrentSubfolder = value;
 }
@@ -3841,7 +3841,7 @@ void Session::handleAlert(libt::alert *a)
 
 void Session::dispatchTorrentAlert(libt::alert *a)
 {
-    TorrentHandle *const torrent = m_torrents.value(static_cast<libt::torrent_alert*>(a)->handle.info_hash());
+    TorrentHandle *const torrent = m_torrents.value(static_cast<const libt::torrent_alert*>(a)->handle.info_hash());
     if (torrent)
         torrent->handleAlert(a);
 }
@@ -3851,14 +3851,14 @@ void Session::createTorrentHandle(const libt::torrent_handle &nativeHandle)
     // Magnet added for preload its metadata
     if (!m_addingTorrents.contains(nativeHandle.info_hash())) return;
 
-    CreateTorrentParams params = m_addingTorrents.take(nativeHandle.info_hash());
+    const CreateTorrentParams params = m_addingTorrents.take(nativeHandle.info_hash());
 
     TorrentHandle *const torrent = new TorrentHandle(this, nativeHandle, params);
     m_torrents.insert(torrent->hash(), torrent);
 
     Logger *const logger = Logger::instance();
 
-    bool fromMagnetUri = !torrent->hasMetadata();
+    const bool fromMagnetUri = !torrent->hasMetadata();
 
     if (params.restored) {
         logger->addMessage(tr("'%1' restored.", "'torrent name' restored.").arg(torrent->name()));
@@ -4002,7 +4002,7 @@ void Session::handlePortmapAlert(libt::portmap_alert *p)
 void Session::handlePeerBlockedAlert(libt::peer_blocked_alert *p)
 {
     boost::system::error_code ec;
-    std::string ip = p->ip.to_string(ec);
+    const std::string ip = p->ip.to_string(ec);
     QString reason;
     switch (p->reason) {
     case libt::peer_blocked_alert::ip_filter:
@@ -4032,7 +4032,7 @@ void Session::handlePeerBlockedAlert(libt::peer_blocked_alert *p)
 void Session::handlePeerBanAlert(libt::peer_ban_alert *p)
 {
     boost::system::error_code ec;
-    std::string ip = p->ip.address().to_string(ec);
+    const std::string ip = p->ip.address().to_string(ec);
     if (!ec)
         Logger::instance()->addPeer(QString::fromLatin1(ip.c_str()), false);
 }
@@ -4098,7 +4098,7 @@ void Session::handleExternalIPAlert(libt::external_ip_alert *p)
 
 void Session::handleSessionStatsAlert(libt::session_stats_alert *p)
 {
-    qreal interval = m_statsUpdateTimer.restart() / 1000.;
+    const qreal interval = m_statsUpdateTimer.restart() / 1000.;
 
     m_status.hasIncomingConnections = static_cast<bool>(p->values[m_metricIndices.net.hasIncomingConnections]);
 
@@ -4113,7 +4113,7 @@ void Session::handleSessionStatsAlert(libt::session_stats_alert *p)
     const auto dhtDownload = p->values[m_metricIndices.dht.dhtBytesIn];
     const auto dhtUpload = p->values[m_metricIndices.dht.dhtBytesOut];
 
-    auto calcRate = [interval](quint64 previous, quint64 current)
+    auto calcRate = [interval](const quint64 previous, const quint64 current)
     {
         Q_ASSERT(current >= previous);
         return static_cast<quint64>((current - previous) / interval);
@@ -4153,7 +4153,7 @@ void Session::handleSessionStatsAlert(libt::session_stats_alert *p)
     m_cacheStatus.readRatio = static_cast<qreal>(numBlocksCacheHits) / std::max(numBlocksCacheHits + numBlocksRead, 1);
     m_cacheStatus.jobQueueLength = p->values[m_metricIndices.disk.queuedDiskJobs];
 
-    quint64 totalJobs = p->values[m_metricIndices.disk.writeJobs] + p->values[m_metricIndices.disk.readJobs]
+    const quint64 totalJobs = p->values[m_metricIndices.disk.writeJobs] + p->values[m_metricIndices.disk.readJobs]
                   + p->values[m_metricIndices.disk.hashJobs];
     m_cacheStatus.averageJobTime = totalJobs > 0
                                    ? (p->values[m_metricIndices.disk.diskJobTime] / totalJobs) : 0;
@@ -4312,7 +4312,7 @@ namespace
         if (!ConvertIfaceLuidToGuid) return QString();
 
         NET_LUID luid;
-        LONG res = ConvertIfaceNameToLuid(name.toStdWString().c_str(), &luid);
+        const LONG res = ConvertIfaceNameToLuid(name.toStdWString().c_str(), &luid);
         if (res == 0) {
             GUID guid;
             if (ConvertIfaceLuidToGuid(&luid, &guid) == 0)
diff --git a/src/base/bittorrent/session.h b/src/base/bittorrent/session.h
index 053d84371..294155e7c 100644
--- a/src/base/bittorrent/session.h
+++ b/src/base/bittorrent/session.h
@@ -543,7 +543,7 @@ namespace BitTorrent
         void handleRedirectedToMagnet(const QString &url, const QString &magnetUri);
 
         // Session reconfiguration triggers
-        void networkOnlineStateChanged(const bool online);
+        void networkOnlineStateChanged(bool online);
         void networkConfigurationChange(const QNetworkConfiguration&);
 
     private:
diff --git a/src/base/bittorrent/torrentcreatorthread.h b/src/base/bittorrent/torrentcreatorthread.h
index 41c991517..010021c5f 100644
--- a/src/base/bittorrent/torrentcreatorthread.h
+++ b/src/base/bittorrent/torrentcreatorthread.h
@@ -57,7 +57,7 @@ namespace BitTorrent
 
         void create(const TorrentCreatorParams &params);
 
-        static int calculateTotalPieces(const QString &inputPath, const int pieceSize, const bool isAlignmentOptimized);
+        static int calculateTotalPieces(const QString &inputPath, int pieceSize, bool isAlignmentOptimized);
 
     protected:
         void run();
diff --git a/src/base/bittorrent/torrenthandle.cpp b/src/base/bittorrent/torrenthandle.cpp
index cfbcd44c9..6cddf36ec 100644
--- a/src/base/bittorrent/torrenthandle.cpp
+++ b/src/base/bittorrent/torrenthandle.cpp
@@ -299,7 +299,7 @@ QString TorrentHandle::rootPath(bool actual) const
     if ((filesCount() > 1) && !hasRootFolder())
         return QString();
 
-    QString firstFilePath = filePath(0);
+    const QString firstFilePath = filePath(0);
     const int slashIndex = firstFilePath.indexOf('/');
     if (slashIndex >= 0)
         return QDir(savePath(actual)).absoluteFilePath(firstFilePath.left(slashIndex));
@@ -462,10 +462,10 @@ bool TorrentHandle::removeUrlSeed(const QUrl &urlSeed)
 bool TorrentHandle::connectPeer(const PeerAddress &peerAddress)
 {
     libt::error_code ec;
-    libt::address addr = libt::address::from_string(peerAddress.ip.toString().toStdString(), ec);
+    const libt::address addr = libt::address::from_string(peerAddress.ip.toString().toStdString(), ec);
     if (ec) return false;
 
-    boost::asio::ip::tcp::endpoint ep(addr, peerAddress.port);
+    const boost::asio::ip::tcp::endpoint ep(addr, peerAddress.port);
     m_nativeHandle.connect_peer(ep);
     return true;
 }
@@ -504,7 +504,7 @@ qreal TorrentHandle::progress() const
         if (m_nativeStatus.total_wanted_done == m_nativeStatus.total_wanted)
             return 1.;
 
-        qreal progress = static_cast<qreal>(m_nativeStatus.total_wanted_done) / m_nativeStatus.total_wanted;
+        const qreal progress = static_cast<qreal>(m_nativeStatus.total_wanted_done) / m_nativeStatus.total_wanted;
         Q_ASSERT((progress >= 0.f) && (progress <= 1.f));
         return progress;
     }
@@ -608,7 +608,7 @@ QStringList TorrentHandle::absoluteFilePaths() const
 {
     if (!hasMetadata()) return QStringList();
 
-    QDir saveDir(savePath(true));
+    const QDir saveDir(savePath(true));
     QStringList res;
     for (int i = 0; i < filesCount(); ++i)
         res << Utils::Fs::expandPathAbs(saveDir.absoluteFilePath(filePath(i)));
@@ -619,12 +619,11 @@ QStringList TorrentHandle::absoluteFilePathsUnwanted() const
 {
     if (!hasMetadata()) return QStringList();
 
-    QDir saveDir(savePath(true));
+    const QDir saveDir(savePath(true));
     QStringList res;
-    std::vector<int> fp;
-    fp = m_nativeHandle.file_priorities();
+    const std::vector<int> fp = m_nativeHandle.file_priorities();
 
-    int count = static_cast<int>(fp.size());
+    const int count = static_cast<int>(fp.size());
     for (int i = 0; i < count; ++i) {
         if (fp[i] == 0) {
             const QString path = Utils::Fs::expandPathAbs(saveDir.absoluteFilePath(filePath(i)));
@@ -638,8 +637,7 @@ QStringList TorrentHandle::absoluteFilePathsUnwanted() const
 
 QVector<int> TorrentHandle::filePriorities() const
 {
-    std::vector<int> fp;
-    fp = m_nativeHandle.file_priorities();
+    const std::vector<int> fp = m_nativeHandle.file_priorities();
 
     return QVector<int>::fromStdVector(fp);
 }
@@ -892,8 +890,8 @@ qulonglong TorrentHandle::eta() const
     const SpeedSampleAvg speedAverage = m_speedMonitor.average();
 
     if (isSeed()) {
-        qreal maxRatioValue = maxRatio();
-        int maxSeedingTimeValue = maxSeedingTime();
+        const qreal maxRatioValue = maxRatio();
+        const int maxSeedingTimeValue = maxSeedingTime();
         if ((maxRatioValue < 0) && (maxSeedingTimeValue < 0)) return MAX_ETA;
 
         qlonglong ratioEta = MAX_ETA;
@@ -964,7 +962,7 @@ int TorrentHandle::totalSeedsCount() const
 
 int TorrentHandle::totalPeersCount() const
 {
-    int peers = m_nativeStatus.num_complete + m_nativeStatus.num_incomplete;
+    const int peers = m_nativeStatus.num_complete + m_nativeStatus.num_incomplete;
     return (peers > 0) ? peers : m_nativeStatus.list_peers;
 }
 
@@ -1102,14 +1100,14 @@ int TorrentHandle::maxSeedingTime() const
 
 qreal TorrentHandle::realRatio() const
 {
-    boost::int64_t upload = m_nativeStatus.all_time_upload;
+    const boost::int64_t upload = m_nativeStatus.all_time_upload;
     // special case for a seeder who lost its stats, also assume nobody will import a 99% done torrent
-    boost::int64_t download = (m_nativeStatus.all_time_download < m_nativeStatus.total_done * 0.01) ? m_nativeStatus.total_done : m_nativeStatus.all_time_download;
+    const boost::int64_t download = (m_nativeStatus.all_time_download < m_nativeStatus.total_done * 0.01) ? m_nativeStatus.total_done : m_nativeStatus.all_time_download;
 
     if (download == 0)
         return (upload == 0) ? 0.0 : MAX_RATIO;
 
-    qreal ratio = upload / static_cast<qreal>(download);
+    const qreal ratio = upload / static_cast<qreal>(download);
     Q_ASSERT(ratio >= 0.0);
     return (ratio > MAX_RATIO) ? MAX_RATIO : ratio;
 }
@@ -1163,7 +1161,7 @@ bool TorrentHandle::setCategory(const QString &category)
         if (!category.isEmpty() && !m_session->categories().contains(category))
             return false;
 
-        QString oldCategory = m_category;
+        const QString oldCategory = m_category;
         m_category = category;
         m_session->handleTorrentCategoryChanged(this, oldCategory);
 
@@ -1229,7 +1227,7 @@ void TorrentHandle::forceRecheck()
     }
 }
 
-void TorrentHandle::setSequentialDownload(bool b)
+void TorrentHandle::setSequentialDownload(const bool b)
 {
     if (b != isSequentialDownload()) {
         m_nativeHandle.set_sequential_download(b);
@@ -1354,8 +1352,8 @@ bool TorrentHandle::saveTorrentFile(const QString &path)
 {
     if (!m_torrentInfo.isValid()) return false;
 
-    libt::create_torrent torrentCreator = libt::create_torrent(*(m_torrentInfo.nativeInfo()), true);
-    libt::entry torrentEntry = torrentCreator.generate();
+    const libt::create_torrent torrentCreator = libt::create_torrent(*(m_torrentInfo.nativeInfo()), true);
+    const libt::entry torrentEntry = torrentCreator.generate();
 
     QVector<char> out;
     libt::bencode(std::back_inserter(out), torrentEntry);
@@ -1436,7 +1434,7 @@ void TorrentHandle::handleStorageMovedFailedAlert(const libtorrent::storage_move
 
 void TorrentHandle::handleTrackerReplyAlert(const libtorrent::tracker_reply_alert *p)
 {
-    QString trackerUrl(p->tracker_url());
+    const QString trackerUrl(p->tracker_url());
     qDebug("Received a tracker reply from %s (Num_peers = %d)", qUtf8Printable(trackerUrl), p->num_peers);
     // Connection was successful now. Remove possible old errors
     m_trackerInfos[trackerUrl].lastMessage.clear(); // Reset error/warning message
@@ -1568,7 +1566,7 @@ void TorrentHandle::handleSaveResumeDataAlert(const libtorrent::save_resume_data
         resumeData["qBt-sequential"] = isSequentialDownload();
     }
     else {
-        auto savePath = resumeData.find_key("save_path")->string();
+        const auto savePath = resumeData.find_key("save_path")->string();
         resumeData["save_path"] = Profile::instance().toPortablePath(QString::fromStdString(savePath)).toStdString();
     }
     resumeData["qBt-savePath"] = m_useAutoTMM ? "" : Profile::instance().toPortablePath(m_savePath).toStdString();
@@ -1610,7 +1608,7 @@ void TorrentHandle::handleFastResumeRejectedAlert(const libtorrent::fastresume_r
 
 void TorrentHandle::handleFileRenamedAlert(const libtorrent::file_renamed_alert *p)
 {
-    QString newName = Utils::Fs::fromNativePath(p->new_name());
+    const QString newName = Utils::Fs::fromNativePath(p->new_name());
 
     // TODO: Check this!
     if (filesCount() > 1) {
@@ -1620,7 +1618,7 @@ void TorrentHandle::handleFileRenamedAlert(const libtorrent::file_renamed_alert
         QString oldPath = oldPathParts.join('/');
         QStringList newPathParts = newName.split('/');
         newPathParts.removeLast();
-        QString newPath = newPathParts.join('/');
+        const QString newPath = newPathParts.join('/');
         if (!newPathParts.isEmpty() && (oldPath != newPath)) {
             qDebug("oldPath(%s) != newPath(%s)", qUtf8Printable(oldPath), qUtf8Printable(newPath));
             oldPath = QString("%1/%2").arg(savePath(true), oldPath);
@@ -1668,7 +1666,7 @@ void TorrentHandle::handleFileCompletedAlert(const libtorrent::file_completed_al
 void TorrentHandle::handleStatsAlert(const libtorrent::stats_alert *p)
 {
     Q_ASSERT(p->interval >= 1000);
-    SpeedSample transferred(p->transferred[libt::stats_alert::download_payload] * 1000LL / p->interval,
+    const SpeedSample transferred(p->transferred[libt::stats_alert::download_payload] * 1000LL / p->interval,
             p->transferred[libt::stats_alert::upload_payload] * 1000LL / p->interval);
     m_speedMonitor.addSample(transferred);
 }
@@ -1723,55 +1721,55 @@ void TorrentHandle::handleAlert(libtorrent::alert *a)
 {
     switch (a->type()) {
     case libt::stats_alert::alert_type:
-        handleStatsAlert(static_cast<libt::stats_alert*>(a));
+        handleStatsAlert(static_cast<const libt::stats_alert*>(a));
         break;
     case libt::file_renamed_alert::alert_type:
-        handleFileRenamedAlert(static_cast<libt::file_renamed_alert*>(a));
+        handleFileRenamedAlert(static_cast<const libt::file_renamed_alert*>(a));
         break;
     case libt::file_rename_failed_alert::alert_type:
-        handleFileRenameFailedAlert(static_cast<libt::file_rename_failed_alert*>(a));
+        handleFileRenameFailedAlert(static_cast<const libt::file_rename_failed_alert*>(a));
         break;
     case libt::file_completed_alert::alert_type:
-        handleFileCompletedAlert(static_cast<libt::file_completed_alert*>(a));
+        handleFileCompletedAlert(static_cast<const libt::file_completed_alert*>(a));
         break;
     case libt::torrent_finished_alert::alert_type:
-        handleTorrentFinishedAlert(static_cast<libt::torrent_finished_alert*>(a));
+        handleTorrentFinishedAlert(static_cast<const libt::torrent_finished_alert*>(a));
         break;
     case libt::save_resume_data_alert::alert_type:
-        handleSaveResumeDataAlert(static_cast<libt::save_resume_data_alert*>(a));
+        handleSaveResumeDataAlert(static_cast<const libt::save_resume_data_alert*>(a));
         break;
     case libt::save_resume_data_failed_alert::alert_type:
-        handleSaveResumeDataFailedAlert(static_cast<libt::save_resume_data_failed_alert*>(a));
+        handleSaveResumeDataFailedAlert(static_cast<const libt::save_resume_data_failed_alert*>(a));
         break;
     case libt::storage_moved_alert::alert_type:
-        handleStorageMovedAlert(static_cast<libt::storage_moved_alert*>(a));
+        handleStorageMovedAlert(static_cast<const libt::storage_moved_alert*>(a));
         break;
     case libt::storage_moved_failed_alert::alert_type:
-        handleStorageMovedFailedAlert(static_cast<libt::storage_moved_failed_alert*>(a));
+        handleStorageMovedFailedAlert(static_cast<const libt::storage_moved_failed_alert*>(a));
         break;
     case libt::torrent_paused_alert::alert_type:
-        handleTorrentPausedAlert(static_cast<libt::torrent_paused_alert*>(a));
+        handleTorrentPausedAlert(static_cast<const libt::torrent_paused_alert*>(a));
         break;
     case libt::torrent_resumed_alert::alert_type:
-        handleTorrentResumedAlert(static_cast<libt::torrent_resumed_alert*>(a));
+        handleTorrentResumedAlert(static_cast<const libt::torrent_resumed_alert*>(a));
         break;
     case libt::tracker_error_alert::alert_type:
-        handleTrackerErrorAlert(static_cast<libt::tracker_error_alert*>(a));
+        handleTrackerErrorAlert(static_cast<const libt::tracker_error_alert*>(a));
         break;
     case libt::tracker_reply_alert::alert_type:
-        handleTrackerReplyAlert(static_cast<libt::tracker_reply_alert*>(a));
+        handleTrackerReplyAlert(static_cast<const libt::tracker_reply_alert*>(a));
         break;
     case libt::tracker_warning_alert::alert_type:
-        handleTrackerWarningAlert(static_cast<libt::tracker_warning_alert*>(a));
+        handleTrackerWarningAlert(static_cast<const libt::tracker_warning_alert*>(a));
         break;
     case libt::metadata_received_alert::alert_type:
-        handleMetadataReceivedAlert(static_cast<libt::metadata_received_alert*>(a));
+        handleMetadataReceivedAlert(static_cast<const libt::metadata_received_alert*>(a));
         break;
     case libt::fastresume_rejected_alert::alert_type:
-        handleFastResumeRejectedAlert(static_cast<libt::fastresume_rejected_alert*>(a));
+        handleFastResumeRejectedAlert(static_cast<const libt::fastresume_rejected_alert*>(a));
         break;
     case libt::torrent_checked_alert::alert_type:
-        handleTorrentCheckedAlert(static_cast<libt::torrent_checked_alert*>(a));
+        handleTorrentCheckedAlert(static_cast<const libt::torrent_checked_alert*>(a));
         break;
     }
 }
@@ -1779,7 +1777,7 @@ void TorrentHandle::handleAlert(libtorrent::alert *a)
 void TorrentHandle::manageIncompleteFiles()
 {
     const bool isAppendExtensionEnabled = m_session->isAppendExtensionEnabled();
-    QVector<qreal> fp = filesProgress();
+    const QVector<qreal> fp = filesProgress();
     if (fp.size() != filesCount()) {
         qDebug() << "skip manageIncompleteFiles because of invalid torrent meta-data or empty file-progress";
         return;
@@ -1898,17 +1896,17 @@ void TorrentHandle::setSeedingTimeLimit(int limit)
     }
 }
 
-void TorrentHandle::setUploadLimit(int limit)
+void TorrentHandle::setUploadLimit(const int limit)
 {
     m_nativeHandle.set_upload_limit(limit);
 }
 
-void TorrentHandle::setDownloadLimit(int limit)
+void TorrentHandle::setDownloadLimit(const int limit)
 {
     m_nativeHandle.set_download_limit(limit);
 }
 
-void TorrentHandle::setSuperSeeding(bool enable)
+void TorrentHandle::setSuperSeeding(const bool enable)
 {
     m_nativeHandle.super_seeding(enable);
 }
@@ -1933,8 +1931,8 @@ void TorrentHandle::prioritizeFiles(const QVector<int> &priorities)
 
     // Reset 'm_hasSeedStatus' if needed in order to react again to
     // 'torrent_finished_alert' and eg show tray notifications
-    QVector<qreal> progress = filesProgress();
-    QVector<int> oldPriorities = filePriorities();
+    const QVector<qreal> progress = filesProgress();
+    const QVector<int> oldPriorities = filePriorities();
     for (int i = 0; i < oldPriorities.size(); ++i) {
         if ((oldPriorities[i] == 0) && (priorities[i] > 0) && (progress[i] < 1.0)) {
             m_hasSeedStatus = false;
@@ -1946,24 +1944,24 @@ void TorrentHandle::prioritizeFiles(const QVector<int> &priorities)
     m_nativeHandle.prioritize_files(priorities.toStdVector());
 
     qDebug() << Q_FUNC_INFO << "Moving unwanted files to .unwanted folder and conversely...";
-    QString spath = savePath(true);
+    const QString spath = savePath(true);
     for (int i = 0; i < priorities.size(); ++i) {
-        QString filepath = filePath(i);
+        const QString filepath = filePath(i);
         // Move unwanted files to a .unwanted subfolder
         if (priorities[i] == 0) {
-            QString oldAbsPath = QDir(spath).absoluteFilePath(filepath);
-            QString parentAbsPath = Utils::Fs::branchPath(oldAbsPath);
+            const QString oldAbsPath = QDir(spath).absoluteFilePath(filepath);
+            const QString parentAbsPath = Utils::Fs::branchPath(oldAbsPath);
             // Make sure the file does not already exists
             if (QDir(parentAbsPath).dirName() != ".unwanted") {
-                QString unwantedAbsPath = parentAbsPath + "/.unwanted";
-                QString newAbsPath = unwantedAbsPath + '/' + Utils::Fs::fileName(filepath);
+                const QString unwantedAbsPath = parentAbsPath + "/.unwanted";
+                const QString newAbsPath = unwantedAbsPath + '/' + Utils::Fs::fileName(filepath);
                 qDebug() << "Unwanted path is" << unwantedAbsPath;
                 if (QFile::exists(newAbsPath)) {
                     qWarning() << "File" << newAbsPath << "already exists at destination.";
                     continue;
                 }
 
-                bool created = QDir().mkpath(unwantedAbsPath);
+                const bool created = QDir().mkpath(unwantedAbsPath);
                 qDebug() << "unwanted folder was created:" << created;
 #ifdef Q_OS_WIN
                 if (created) {
@@ -1984,10 +1982,10 @@ void TorrentHandle::prioritizeFiles(const QVector<int> &priorities)
 
         // Move wanted files back to their original folder
         if (priorities[i] > 0) {
-            QString parentRelPath = Utils::Fs::branchPath(filepath);
+            const QString parentRelPath = Utils::Fs::branchPath(filepath);
             if (QDir(parentRelPath).dirName() == ".unwanted") {
-                QString oldName = Utils::Fs::fileName(filepath);
-                QString newRelPath = Utils::Fs::branchPath(parentRelPath);
+                const QString oldName = Utils::Fs::fileName(filepath);
+                const QString newRelPath = Utils::Fs::branchPath(parentRelPath);
                 if (newRelPath.isEmpty())
                     renameFile(i, oldName);
                 else
diff --git a/src/base/bittorrent/torrentinfo.cpp b/src/base/bittorrent/torrentinfo.cpp
index 3245e59fe..4f11799df 100644
--- a/src/base/bittorrent/torrentinfo.cpp
+++ b/src/base/bittorrent/torrentinfo.cpp
@@ -146,7 +146,7 @@ QString TorrentInfo::name() const
 QDateTime TorrentInfo::creationDate() const
 {
     if (!isValid()) return QDateTime();
-    boost::optional<time_t> t = m_nativeInfo->creation_date();
+    const boost::optional<time_t> t = m_nativeInfo->creation_date();
     return t ? QDateTime::fromTime_t(*t) : QDateTime();
 }
 
@@ -186,7 +186,7 @@ int TorrentInfo::pieceLength() const
     return m_nativeInfo->piece_length();
 }
 
-int TorrentInfo::pieceLength(int index) const
+int TorrentInfo::pieceLength(const int index) const
 {
     if (!isValid()) return -1;
     return m_nativeInfo->piece_size(index);
@@ -198,7 +198,7 @@ int TorrentInfo::piecesCount() const
     return m_nativeInfo->num_pieces();
 }
 
-QString TorrentInfo::filePath(int index) const
+QString TorrentInfo::filePath(const int index) const
 {
     if (!isValid()) return QString();
     return Utils::Fs::fromNativePath(QString::fromStdString(m_nativeInfo->files().file_path(index)));
@@ -213,24 +213,24 @@ QStringList TorrentInfo::filePaths() const
     return list;
 }
 
-QString TorrentInfo::fileName(int index) const
+QString TorrentInfo::fileName(const int index) const
 {
     return Utils::Fs::fileName(filePath(index));
 }
 
-QString TorrentInfo::origFilePath(int index) const
+QString TorrentInfo::origFilePath(const int index) const
 {
     if (!isValid()) return QString();
     return Utils::Fs::fromNativePath(QString::fromStdString(m_nativeInfo->orig_files().file_path(index)));
 }
 
-qlonglong TorrentInfo::fileSize(int index) const
+qlonglong TorrentInfo::fileSize(const int index) const
 {
     if (!isValid()) return -1;
     return m_nativeInfo->files().file_size(index);
 }
 
-qlonglong TorrentInfo::fileOffset(int index) const
+qlonglong TorrentInfo::fileOffset(const int index) const
 {
     if (!isValid()) return -1;
     return m_nativeInfo->files().file_offset(index);
@@ -265,10 +265,10 @@ QByteArray TorrentInfo::metadata() const
     return QByteArray(m_nativeInfo->metadata().get(), m_nativeInfo->metadata_size());
 }
 
-QStringList TorrentInfo::filesForPiece(int pieceIndex) const
+QStringList TorrentInfo::filesForPiece(const int pieceIndex) const
 {
     // no checks here because fileIndicesForPiece() will return an empty list
-    QVector<int> fileIndices = fileIndicesForPiece(pieceIndex);
+    const QVector<int> fileIndices = fileIndicesForPiece(pieceIndex);
 
     QStringList res;
     res.reserve(fileIndices.size());
@@ -278,12 +278,12 @@ QStringList TorrentInfo::filesForPiece(int pieceIndex) const
     return res;
 }
 
-QVector<int> TorrentInfo::fileIndicesForPiece(int pieceIndex) const
+QVector<int> TorrentInfo::fileIndicesForPiece(const int pieceIndex) const
 {
     if (!isValid() || (pieceIndex < 0) || (pieceIndex >= piecesCount()))
         return QVector<int>();
 
-    std::vector<libt::file_slice> files(
+    const std::vector<libt::file_slice> files(
         nativeInfo()->map_block(pieceIndex, 0, nativeInfo()->piece_size(pieceIndex)));
     QVector<int> res;
     res.reserve(int(files.size()));
@@ -313,7 +313,7 @@ TorrentInfo::PieceRange TorrentInfo::filePieces(const QString &file) const
     if (!isValid()) // if we do not check here the debug message will be printed, which would be not correct
         return {};
 
-    int index = fileIndex(file);
+    const int index = fileIndex(file);
     if (index == -1) {
         qDebug() << "Filename" << file << "was not found in torrent" << name();
         return {};
@@ -321,7 +321,7 @@ TorrentInfo::PieceRange TorrentInfo::filePieces(const QString &file) const
     return filePieces(index);
 }
 
-TorrentInfo::PieceRange TorrentInfo::filePieces(int fileIndex) const
+TorrentInfo::PieceRange TorrentInfo::filePieces(const int fileIndex) const
 {
     if (!isValid())
         return {};
@@ -387,7 +387,7 @@ void TorrentInfo::stripRootFolder()
     libtorrent::file_storage files = m_nativeInfo->files();
 
     // Solution for case of renamed root folder
-    std::string testName = filePath(0).split('/').value(0).toStdString();
+    const std::string testName = filePath(0).split('/').value(0).toStdString();
     if (files.name() != testName) {
         files.set_name(testName);
         for (int i = 0; i < files.num_files(); ++i)
diff --git a/src/base/bittorrent/tracker.cpp b/src/base/bittorrent/tracker.cpp
index 98cdda406..d7aab38f8 100644
--- a/src/base/bittorrent/tracker.cpp
+++ b/src/base/bittorrent/tracker.cpp
@@ -63,7 +63,7 @@ QString Peer::uid() const
     return ip.toString() + ':' + QString::number(port);
 }
 
-libtorrent::entry Peer::toEntry(bool noPeerId) const
+libtorrent::entry Peer::toEntry(const bool noPeerId) const
 {
     libtorrent::entry::dictionary_type peerMap;
     if (!noPeerId)
diff --git a/src/gui/properties/proptabbar.cpp b/src/gui/properties/proptabbar.cpp
index 46153b659..edb2eaaa3 100644
--- a/src/gui/properties/proptabbar.cpp
+++ b/src/gui/properties/proptabbar.cpp
@@ -120,9 +120,9 @@ int PropTabBar::currentIndex() const
 void PropTabBar::setCurrentIndex(int index)
 {
     if (index >= m_btnGroup->buttons().size())
-    index = 0;
+        index = 0;
     // If asked to hide or if the currently selected tab is clicked
-    if (index < 0 || m_currentIndex == index) {
+    if ((index < 0) || (m_currentIndex == index)) {
         if (m_currentIndex >= 0) {
           m_btnGroup->button(m_currentIndex)->setDown(false);
           m_currentIndex = -1;
diff --git a/src/gui/properties/trackerlistwidget.cpp b/src/gui/properties/trackerlistwidget.cpp
index c27494968..40b1263a4 100644
--- a/src/gui/properties/trackerlistwidget.cpp
+++ b/src/gui/properties/trackerlistwidget.cpp
@@ -149,7 +149,7 @@ QList<QTreeWidgetItem*> TrackerListWidget::getSelectedTrackerItems() const
     return selectedTrackers;
 }
 
-void TrackerListWidget::setRowColor(int row, QColor color)
+void TrackerListWidget::setRowColor(const int row, QColor color)
 {
     const int nbColumns = columnCount();
     QTreeWidgetItem *item = topLevelItem(row);
diff --git a/src/gui/search/pluginselectdialog.cpp b/src/gui/search/pluginselectdialog.cpp
index f2bf24c5d..432154d93 100644
--- a/src/gui/search/pluginselectdialog.cpp
+++ b/src/gui/search/pluginselectdialog.cpp
@@ -228,7 +228,7 @@ void PluginSelectDialog::enableSelection(bool enable)
 }
 
 // Set the color of a row in data model
-void PluginSelectDialog::setRowColor(int row, QString color)
+void PluginSelectDialog::setRowColor(const int row, QString color)
 {
     QTreeWidgetItem *item = m_ui->pluginsTree->topLevelItem(row);
     for (int i = 0; i < m_ui->pluginsTree->columnCount(); ++i) {
diff --git a/src/gui/transferlistmodel.cpp b/src/gui/transferlistmodel.cpp
index a0ffa2998..dd1f549ce 100644
--- a/src/gui/transferlistmodel.cpp
+++ b/src/gui/transferlistmodel.cpp
@@ -466,8 +466,8 @@ QIcon getErrorIcon()
 
 bool isDarkTheme()
 {
-    QPalette pal = QApplication::palette();
+    const QPalette pal = QApplication::palette();
     // QPalette::Base is used for the background of the Treeview
-    QColor color = pal.color(QPalette::Active, QPalette::Base);
+    const QColor color = pal.color(QPalette::Active, QPalette::Base);
     return (color.lightness() < 127);
 }
diff --git a/src/webui/api/appcontroller.cpp b/src/webui/api/appcontroller.cpp
index bc3539035..c0e239457 100644
--- a/src/webui/api/appcontroller.cpp
+++ b/src/webui/api/appcontroller.cpp
@@ -321,7 +321,7 @@ void AppController::setPreferencesAction()
 
         // Update deleted folders
         for (auto i = oldScanDirs.cbegin(); i != oldScanDirs.cend(); ++i) {
-            QString folder = i.key();
+            const QString folder = i.key();
             if (!scanDirs.contains(folder)) {
                 model->removePath(folder);
                 qDebug("Removed watched folder %s", qUtf8Printable(folder));