diff --git a/src/libs/qtcreatorcdbext/qtcreatorcdbextension.cpp b/src/libs/qtcreatorcdbext/qtcreatorcdbextension.cpp
index e84b8a8ec3bde72ee1d367aec28439574fdc77e5..d0e354dd1a571f34afbabd6119187c647e80ff75 100644
--- a/src/libs/qtcreatorcdbext/qtcreatorcdbextension.cpp
+++ b/src/libs/qtcreatorcdbext/qtcreatorcdbextension.cpp
@@ -127,7 +127,7 @@ static const CommandDescription commandDescriptions[] = {
  "Prints local variables of symbol group in GDBMI or debug format",
  "[-t token] [-v] [T formats] [-I formats] [-f debugfilter] [-c] [-h] [-d]\n[-e expand-list] [-u uninitialized-list]\n"
  "[-W] [-w watch-iname watch-expression] <frame-number> [iname]\n"
- "-h human-readable ouput\n"
+ "-h human-readable output\n"
  "-v increase verboseness of dumping\n"
  "-d debug output\n"
  "-f debug_filter\n"
@@ -142,7 +142,7 @@ static const CommandDescription commandDescriptions[] = {
 {"watches",
  "Prints watches variables of symbol group in GDBMI or debug format",
  "[-t token] [-v] [T formats] [-I formats] [-f debugfilter] [-c] [-h] [-d] <iname>\n"
- "-h human-readable ouput\n"
+ "-h human-readable output\n"
  "-v increase verboseness of dumping\n"
  "-d debug output\n"
  "-f debug_filter\n"
diff --git a/src/libs/qtcreatorcdbext/symbolgroupvalue.cpp b/src/libs/qtcreatorcdbext/symbolgroupvalue.cpp
index 0c40227567fb4c921b56e7ca5cf16288ebd954bd..6982c009208c99327bd9853db7faa198f84ce25a 100644
--- a/src/libs/qtcreatorcdbext/symbolgroupvalue.cpp
+++ b/src/libs/qtcreatorcdbext/symbolgroupvalue.cpp
@@ -610,7 +610,7 @@ std::string SymbolGroupValue::resolveType(const std::string &typeIn,
 
     // Use the module of the current symbol group for templates.
     // This is because resolving some template types (std::list<> has been
-    // observed to result in 'QtGui4d!std::list', which subseqently fails.
+    // observed to result in 'QtGui4d!std::list', which subsequently fails.
     if (!currentModule.empty() && stripped.find('<') != std::string::npos) {
         std::string trc = currentModule;
         trc.push_back('!');
diff --git a/src/libs/utils/abstractprocess_win.cpp b/src/libs/utils/abstractprocess_win.cpp
index 79e55632a9e1195093d93bc8612e43876f13013b..51aea69fcaef9c2e3005756fe40ee1ca71699d0a 100644
--- a/src/libs/utils/abstractprocess_win.cpp
+++ b/src/libs/utils/abstractprocess_win.cpp
@@ -59,7 +59,7 @@ static QString quoteWinCommand(const QString &program)
 {
     const QChar doubleQuote = QLatin1Char('"');
 
-    // add the programm as the first arg ... it works better
+    // add the program as the first arg ... it works better
     QString programName = program;
     programName.replace(QLatin1Char('/'), QLatin1Char('\\'));
     if (!programName.startsWith(doubleQuote) && !programName.endsWith(doubleQuote)
diff --git a/src/libs/utils/environmentmodel.cpp b/src/libs/utils/environmentmodel.cpp
index 577a40d8a98a4f779d2d720a903151d26d0cb9f6..6a1b14ee57216ac78511f40542d24633d1105843 100644
--- a/src/libs/utils/environmentmodel.cpp
+++ b/src/libs/utils/environmentmodel.cpp
@@ -325,7 +325,7 @@ void EnvironmentModel::unsetVariable(const QString &name)
     int pos = m_d->findInChanges(name);
     if (pos != -1) {
         m_d->m_items[pos].unset = true;
-        m_d->m_items[pos].value = QString();
+        m_d->m_items[pos].value.clear();
         m_d->updateResultEnvironment();
         emit dataChanged(index(row, 0, QModelIndex()), index(row, 1, QModelIndex()));
         emit userChangesChanged();
diff --git a/src/plugins/coreplugin/externaltool.cpp b/src/plugins/coreplugin/externaltool.cpp
index cab415b29613556c6703efaed6a5301930aef1f1..c30b939e19744967179768cd1dab7a13826c5e25 100644
--- a/src/plugins/coreplugin/externaltool.cpp
+++ b/src/plugins/coreplugin/externaltool.cpp
@@ -500,7 +500,7 @@ bool ExternalTool::save(QString *errorMessage) const
     return true;
 }
 
-bool ExternalTool::operator==(const ExternalTool &other)
+bool ExternalTool::operator==(const ExternalTool &other) const
 {
     return m_id == other.m_id
             && m_description == other.m_description
@@ -537,9 +537,9 @@ bool ExternalToolRunner::resolve()
 {
     if (!m_tool)
         return false;
-    m_resolvedExecutable = QString::null;
-    m_resolvedArguments = QString::null;
-    m_resolvedWorkingDirectory = QString::null;
+    m_resolvedExecutable.clear();
+    m_resolvedArguments.clear();
+    m_resolvedWorkingDirectory.clear();
     { // executable
         foreach (const QString &executable, m_tool->executables()) {
             QString resolved = Utils::expandMacros(executable,
@@ -813,7 +813,7 @@ void ExternalToolManager::setToolsByCategory(const QMap<QString, QList<Internal:
         it.next();
         ActionContainer *container = 0;
         const QString &containerName = it.key();
-        if (containerName == QString()) { // no displayCategory, so put into external tools menu directly
+        if (containerName.isEmpty()) { // no displayCategory, so put into external tools menu directly
             container = mexternaltools;
         } else {
             if (m_containers.contains(containerName)) {
diff --git a/src/plugins/coreplugin/externaltool.h b/src/plugins/coreplugin/externaltool.h
index bd5ddbc31f7874d8a43efc66debd187993bcca97..8edeefd37613f747332d98f5f164330decb4ec70 100644
--- a/src/plugins/coreplugin/externaltool.h
+++ b/src/plugins/coreplugin/externaltool.h
@@ -93,8 +93,8 @@ public:
 
     bool save(QString *errorMessage = 0) const;
 
-    bool operator==(const ExternalTool &other);
-    bool operator!=(const ExternalTool &other) { return !((*this) == other); }
+    bool operator==(const ExternalTool &other) const;
+    bool operator!=(const ExternalTool &other) const { return !((*this) == other); }
     ExternalTool &operator=(const ExternalTool &other);
 
     void setId(const QString &id);
diff --git a/src/plugins/coreplugin/filemanager.cpp b/src/plugins/coreplugin/filemanager.cpp
index 6c770ff812a3301c9d2acc8bca36b91f515482a3..f49df606612399312e3cf3ee91d85ec6f53ef763 100644
--- a/src/plugins/coreplugin/filemanager.cpp
+++ b/src/plugins/coreplugin/filemanager.cpp
@@ -339,7 +339,7 @@ void FileManager::renamedFile(const QString &from, const QString &to)
     }
 }
 
-/* Removes all occurrances of the IFile from m_filesWithWatch and m_states.
+/* Removes all occurrences of the IFile from m_filesWithWatch and m_states.
    If that results in a file no longer being referenced by any IFile, this
    also removes the file watcher.
 */
diff --git a/src/plugins/coreplugin/filemanager.h b/src/plugins/coreplugin/filemanager.h
index 7010f92d1d559961e22755a99cc2b46f59dd7e64..1151fca73b193c53ee739de53fb1a412923220f7 100644
--- a/src/plugins/coreplugin/filemanager.h
+++ b/src/plugins/coreplugin/filemanager.h
@@ -112,7 +112,7 @@ public:
     QList<IFile *> saveModifiedFiles(const QList<IFile *> &files,
                                      bool *cancelled = 0,
                                      const QString &message = QString(),
-                                     const QString &alwaysSaveMessage = QString::null,
+                                     const QString &alwaysSaveMessage = QString(),
                                      bool *alwaysSave = 0);
 
 
@@ -167,7 +167,7 @@ private:
     QList<IFile *> saveModifiedFiles(const QList<IFile *> &files,
                                bool *cancelled, bool silently,
                                const QString &message,
-                               const QString &alwaysSaveMessage = QString::null,
+                               const QString &alwaysSaveMessage = QString(),
                                bool *alwaysSave = 0);
 
     Internal::FileManagerPrivate *d;
diff --git a/src/plugins/debugger/breakwindow.cpp b/src/plugins/debugger/breakwindow.cpp
index a6a9f3b1c09d49e75d7dae76ec6e045590a3d3a9..9a5415fc2797a62ef4ac1a1e7c5dae4d5d08daee 100644
--- a/src/plugins/debugger/breakwindow.cpp
+++ b/src/plugins/debugger/breakwindow.cpp
@@ -61,7 +61,7 @@ namespace Internal {
 // breakpoint type. The controls not applicable to the current type
 // (say function name for file-and-line) are disabled and cleared out.
 // However,the values are saved and restored once the respective mode
-// is again choosen, which is done using m_savedParameters and
+// is again chosen, which is done using m_savedParameters and
 // setters/getters taking the parts mask enumeration parameter.
 //
 ///////////////////////////////////////////////////////////////////////
diff --git a/src/plugins/debugger/cdb/cdbengine.cpp b/src/plugins/debugger/cdb/cdbengine.cpp
index 34a433b50eab2838f2111434ee29f5af729207ea..790cb8a7312960ae76a0f56a730c29ed0a8d7857 100644
--- a/src/plugins/debugger/cdb/cdbengine.cpp
+++ b/src/plugins/debugger/cdb/cdbengine.cpp
@@ -2472,7 +2472,7 @@ static inline void formatCdbBreakPointResponse(BreakpointId id, const Breakpoint
 void CdbEngine::handleBreakPoints(const CdbExtensionCommandPtr &reply)
 {
     if (debugBreakpoints)
-        qDebug("CdbEngine::handleBreakPoints: sucess=%d: %s", reply->success, reply->reply.constData());
+        qDebug("CdbEngine::handleBreakPoints: success=%d: %s", reply->success, reply->reply.constData());
     if (!reply->success) {
         showMessage(QString::fromAscii(reply->errorMessage), LogError);
         return;
diff --git a/src/plugins/debugger/consolewindow.cpp b/src/plugins/debugger/consolewindow.cpp
index 66900eb66eea35862e144ebe1f71575b304b0c44..8a0b98156635eca42b3bc77b36b581c611717a5e 100644
--- a/src/plugins/debugger/consolewindow.cpp
+++ b/src/plugins/debugger/consolewindow.cpp
@@ -310,7 +310,7 @@ void ConsoleWindow::showOutput(int channel, const QString &output)
             line.truncate(n);
             line += QLatin1String(" [...] <cut off>");
         }
-        m_console->appendPlainText(charForChannel(channel) + line + "\n");
+        m_console->appendPlainText(charForChannel(channel) + line + '\n');
     }
     QTextCursor cursor = m_console->textCursor();
     cursor.movePosition(QTextCursor::End);
diff --git a/src/plugins/debugger/disassembleragent.cpp b/src/plugins/debugger/disassembleragent.cpp
index a308ccba5347b79dac743aa7300b1bce8eb8ecc9..6047530fac271b9cc7700f2ad67094e27325656e 100644
--- a/src/plugins/debugger/disassembleragent.cpp
+++ b/src/plugins/debugger/disassembleragent.cpp
@@ -271,12 +271,12 @@ void DisassemblerAgent::setContents(const DisassemblerLines &contents)
     for (int i = 0, n = contents.size(); i != n; ++i) {
         const DisassemblerLine &dl = contents.at(i);
         if (dl.address) {
-            str += QString("0x");
+            str += QLatin1String("0x");
             str += QString::number(dl.address, 16);
-            str += "  ";
+            str += QLatin1String("  ");
         }
         str += dl.data;
-        str += "\n";
+        str += QLatin1Char('\n');
     }
     plainTextEdit->setPlainText(str);
     plainTextEdit->setReadOnly(true);
diff --git a/src/plugins/debugger/gdb/classicgdbengine.cpp b/src/plugins/debugger/gdb/classicgdbengine.cpp
index ad9bad466bae6bffd3afa6f66ad0ab3d31e6e82f..1b0c2e61b1f216fbd84f824d75611ab258e7262f 100644
--- a/src/plugins/debugger/gdb/classicgdbengine.cpp
+++ b/src/plugins/debugger/gdb/classicgdbengine.cpp
@@ -280,7 +280,7 @@ void GdbEngine::updateSubItemClassic(const WatchData &data0)
         if (debuggerCore()->boolSetting(AutoDerefPointers)) {
             // Try automatic dereferentiation
             data.exp = "(*(" + data.exp + "))";
-            data.type = data.type + "."; // FIXME: fragile HACK to avoid recursion
+            data.type = data.type + '.'; // FIXME: fragile HACK to avoid recursion
             insertData(data);
         } else {
             data.setChildrenUnneeded();
diff --git a/src/plugins/debugger/gdb/codagdbadapter.cpp b/src/plugins/debugger/gdb/codagdbadapter.cpp
index 1439b74909d4fba446a192c20e34ab76520d2630..a88eb688aec351d7dfbfcfc3b73e8eb5805aaf5d 100644
--- a/src/plugins/debugger/gdb/codagdbadapter.cpp
+++ b/src/plugins/debugger/gdb/codagdbadapter.cpp
@@ -597,7 +597,7 @@ void CodaGdbAdapter::handleGdbServerCommand(const QByteArray &cmd)
         sendGdbServerAck();
         logMessage(_("Not implemented 'Continue with signal' %1: ").arg(signalNumber),
             LogWarning);
-        sendGdbServerMessage("O" + QByteArray("Console output").toHex());
+        sendGdbServerMessage('O' + QByteArray("Console output").toHex());
         sendGdbServerMessage("W81"); // "Process exited with result 1
         sendTrkContinue();
     }
diff --git a/src/plugins/debugger/gdb/gdbengine.cpp b/src/plugins/debugger/gdb/gdbengine.cpp
index 3e1e9c89366722e10256e21accc5c9463c850020..ad0ea208f3c67a8ea2df7a8f00bf9b6ef044c453 100644
--- a/src/plugins/debugger/gdb/gdbengine.cpp
+++ b/src/plugins/debugger/gdb/gdbengine.cpp
@@ -2782,7 +2782,7 @@ void GdbEngine::requestModuleSymbols(const QString &moduleName)
     QString fileName = tf.fileName();
     tf.close();
     postCommand("maint print msymbols " + fileName.toLocal8Bit()
-            + " " + moduleName.toLocal8Bit(),
+            + ' ' + moduleName.toLocal8Bit(),
         NeedsStop, CB(handleShowModuleSymbols),
         QVariant(moduleName + QLatin1Char('@') +  fileName));
 }
diff --git a/src/plugins/debugger/gdb/trkgdbadapter.cpp b/src/plugins/debugger/gdb/trkgdbadapter.cpp
index 5876e25e07fb711300892500d3a365767288df6f..fec80ce5962cd207e1d61e955b13c3879b66e20b 100644
--- a/src/plugins/debugger/gdb/trkgdbadapter.cpp
+++ b/src/plugins/debugger/gdb/trkgdbadapter.cpp
@@ -837,7 +837,7 @@ void TrkGdbAdapter::handleGdbServerCommand(const QByteArray &cmd)
         }
     } // qPart/qXfer
 
-    else if (cmd.startsWith("X")) {
+    else if (cmd.startsWith('X')) {
         logMessage(msgGdbPacket(QLatin1String("Write memory")));
         // X addr,length
         sendGdbServerAck();
diff --git a/src/plugins/debugger/lldb/guest/lldbengineguest.cpp b/src/plugins/debugger/lldb/guest/lldbengineguest.cpp
index bb8b1164bea40b81a93c52271e2d44fba0c4a349..84644bf1ebd5d5181680ab10db72f3d9bdf46942 100644
--- a/src/plugins/debugger/lldb/guest/lldbengineguest.cpp
+++ b/src/plugins/debugger/lldb/guest/lldbengineguest.cpp
@@ -350,7 +350,7 @@ void LldbEngineGuest::requestUpdateWatchData(const Internal::WatchData &data,
 void LldbEngineGuest::getWatchDataR(lldb::SBValue v, int level,
         const QByteArray &p_iname, QList<WatchData> &wd)
 {
-    QByteArray iname = p_iname + "." + QByteArray(v.GetName());
+    QByteArray iname = p_iname + '.' + QByteArray(v.GetName());
     m_localesCache.insert(QString::fromLocal8Bit(iname), v);
 
 #if defined(HAVE_LLDB_PRIVATE)
@@ -584,7 +584,7 @@ void LldbEngineGuest::updateThreads()
         ThreadData thread;
         thread.id = t.GetThreadID();
         thread.targetId = QString::number(t.GetThreadID());
-        thread.core = QString();
+        thread.core.clear();
         thread.state = QString::number(t.GetStopReason());
 
         switch (t.GetStopReason()) {
diff --git a/src/plugins/debugger/qml/qmlcppengine.cpp b/src/plugins/debugger/qml/qmlcppengine.cpp
index 9d39a2e5b4ca0681f11577c87b634201eb67fcee..1fd703ec320463eb19dde87f6992122065e9390d 100644
--- a/src/plugins/debugger/qml/qmlcppengine.cpp
+++ b/src/plugins/debugger/qml/qmlcppengine.cpp
@@ -368,7 +368,7 @@ void QmlCppEngine::interruptInferior()
 
 void QmlCppEngine::requestInterruptInferior()
 {
-    EDEBUG("\nMASTER REQUEST INTERUPT INFERIOR");
+    EDEBUG("\nMASTER REQUEST INTERRUPT INFERIOR");
     DebuggerEngine::requestInterruptInferior();
     d->m_cppEngine->requestInterruptInferior();
 }
diff --git a/src/plugins/debugger/qml/qmlengine.cpp b/src/plugins/debugger/qml/qmlengine.cpp
index b390df29a9f52fb95f6d92ad0dbd43044ce4e02a..4b0494cdb997a720c684305b54c656138753060a 100644
--- a/src/plugins/debugger/qml/qmlengine.cpp
+++ b/src/plugins/debugger/qml/qmlengine.cpp
@@ -826,9 +826,9 @@ void QmlEngine::messageReceived(const QByteArray &message)
             logMessage(LogReceive, logString);
 
             QString msg = stackFrames.isEmpty()
-                ? tr("<p>An Uncaught Exception occured:</p><p>%2</p>")
+                ? tr("<p>An Uncaught Exception occurred:</p><p>%2</p>")
                     .arg(Qt::escape(error))
-                : tr("<p>An Uncaught Exception occured in <i>%1</i>:</p><p>%2</p>")
+                : tr("<p>An Uncaught Exception occurred in <i>%1</i>:</p><p>%2</p>")
                     .arg(stackFrames.value(0).file, Qt::escape(error));
             showMessageBox(QMessageBox::Information, tr("Uncaught Exception"), msg);
         } else {
diff --git a/src/plugins/debugger/shared/backtrace.cpp b/src/plugins/debugger/shared/backtrace.cpp
index 5535bc8d011b3f6993b82a1bf17805754936d20b..99a787a6a429fa50911f2ba5f495376806e89ccc 100644
--- a/src/plugins/debugger/shared/backtrace.cpp
+++ b/src/plugins/debugger/shared/backtrace.cpp
@@ -61,7 +61,7 @@ void dumpBacktrace(int maxdepth)
     proc.start("addr2line", args);
     proc.waitForStarted();
     for (int i = 0; i < qMin(size, maxdepth); i++)
-        proc.write("0x" + QByteArray::number(quintptr(bt[i]), 16) + "\n");
+        proc.write("0x" + QByteArray::number(quintptr(bt[i]), 16) + '\n');
     proc.closeWriteChannel();
     QByteArray out = proc.readAllStandardOutput();
     qDebug() << QCoreApplication::arguments().at(0);
diff --git a/src/plugins/fakevim/fakevimhandler.cpp b/src/plugins/fakevim/fakevimhandler.cpp
index c9fbaff8eaae88e7df6186be3fa8cf5f9859980b..5d26025005114032faf2cbe13d26303be67c3fbc 100644
--- a/src/plugins/fakevim/fakevimhandler.cpp
+++ b/src/plugins/fakevim/fakevimhandler.cpp
@@ -1963,7 +1963,7 @@ EventResult FakeVimHandler::Private::handleCommandMode(const Input &input)
             m_movetype = MoveExclusive;
             m_subsubmode = SearchSubSubMode;
             m_commandPrefix = QLatin1Char(m_lastSearchForward ? '/' : '?');
-            m_commandBuffer = QString();
+            m_commandBuffer.clear();
             updateMiniBuffer();
         }
     } else if (input.is('`')) {
diff --git a/src/plugins/perforce/perforceplugin.cpp b/src/plugins/perforce/perforceplugin.cpp
index 39b1c74361a149ce581249fa604085a03e687680..24e83723f993e85e001596fe7fa1596855128552 100644
--- a/src/plugins/perforce/perforceplugin.cpp
+++ b/src/plugins/perforce/perforceplugin.cpp
@@ -1432,7 +1432,7 @@ QString PerforcePlugin::fileNameFromPerforceName(const QString& perforceName,
     const PerforceResponse response = runP4Cmd(m_settings.topLevelSymLinkTarget(), args, flags);
     if (response.error) {
         *errorMessage = msgWhereFailed(perforceName, response.message);
-        return QString::null;
+        return QString();
     }
 
     QString output = response.stdOut;
diff --git a/src/plugins/projectexplorer/abi.cpp b/src/plugins/projectexplorer/abi.cpp
index f6b934abdff7d787ce32fc6bd572f4d1dc26fc57..903e65eef393e81f9199147946419ce062eb9192 100644
--- a/src/plugins/projectexplorer/abi.cpp
+++ b/src/plugins/projectexplorer/abi.cpp
@@ -270,7 +270,7 @@ QString Abi::toString(const OSFlavor &of)
         return QLatin1String("msys");
     case ProjectExplorer::Abi::WindowsCEFlavor:
         return QLatin1String("ce");
-    case ProjectExplorer::Abi::UnknownFlavor: // fall throught!
+    case ProjectExplorer::Abi::UnknownFlavor: // fall through!
     default:
         return QLatin1String("unknown");
     }
diff --git a/src/plugins/projectexplorer/outputparser_test.cpp b/src/plugins/projectexplorer/outputparser_test.cpp
index 19e85c970cd756cf01504590b7f106e651d08131..9bbf21937d35071303562057eca109af813ef65e 100644
--- a/src/plugins/projectexplorer/outputparser_test.cpp
+++ b/src/plugins/projectexplorer/outputparser_test.cpp
@@ -171,10 +171,10 @@ void OutputParserTester::taskAdded(const ProjectExplorer::Task &task)
 
 void OutputParserTester::reset()
 {
-    m_receivedStdErrChildLine = QString();
-    m_receivedStdOutChildLine = QString();
+    m_receivedStdErrChildLine.clear();
+    m_receivedStdOutChildLine.clear();
     m_receivedTasks.clear();
-    m_receivedOutput = QString();
+    m_receivedOutput.clear();
 }
 
 #endif
diff --git a/src/plugins/projectexplorer/projectexplorer.cpp b/src/plugins/projectexplorer/projectexplorer.cpp
index 75b4b17b4e409d8519965fadfedd6a3f6a11470c..508e31ae0d33a3c4235593860172c2fbd6609a76 100644
--- a/src/plugins/projectexplorer/projectexplorer.cpp
+++ b/src/plugins/projectexplorer/projectexplorer.cpp
@@ -1353,7 +1353,8 @@ void ProjectExplorerPlugin::restoreSession()
     // Converts "filename" "+45" or "filename" ":23"
     // into     "filename+45"   and "filename:23"
     foreach (const QString &str, arguments) {
-        if (!combinedList.isEmpty() && (str.startsWith("+") || str.startsWith(":"))) {
+        if (!combinedList.isEmpty() && (str.startsWith(QLatin1Char('+'))
+                                        || str.startsWith(QLatin1Char(':')))) {
             combinedList.last().append(str);
         } else {
             combinedList << str;
@@ -2209,7 +2210,7 @@ QString ProjectExplorerPlugin::directoryFor(Node *node)
         // We figure out a commonPath from the subfolders
         QStringList list;
         foreach (FolderNode *f, folder->subFolderNodes())
-            list << f->path() + "/";
+            list << f->path() + QLatin1Char('/');
         if (list.isEmpty())
             location = path.left(path.indexOf('#'));
         else
@@ -2432,7 +2433,7 @@ void ProjectExplorerPlugin::renameFile(Node *node, const QString &to)
         return;
     QString orgFilePath = QFileInfo(node->path()).absoluteFilePath();
     QString dir = QFileInfo(orgFilePath).absolutePath();
-    QString newFilePath = dir + "/" + to;
+    QString newFilePath = dir + QLatin1Char('/') + to;
     Core::ICore *core = Core::ICore::instance();
     Core::IVersionControl *vc = core->vcsManager()->findVersionControlForDirectory(dir);
     bool result = false;
diff --git a/src/plugins/projectexplorer/targetselector.h b/src/plugins/projectexplorer/targetselector.h
index b637ade859462e8f681b7b3de1ffcc11e1e6c194..fd3a7f4f93cdc5630be21a67e9d6f3ee2069004d 100644
--- a/src/plugins/projectexplorer/targetselector.h
+++ b/src/plugins/projectexplorer/targetselector.h
@@ -81,7 +81,7 @@ public slots:
 
 signals:
     void removeButtonClicked();
-    // This signal is emited whenever the target pointed to by the indices
+    // This signal is emitted whenever the target pointed to by the indices
     // has changed.
     void currentChanged(int targetIndex, int subIndex);
 
diff --git a/src/plugins/qmldesigner/components/itemlibrary/itemlibrarymodel.cpp b/src/plugins/qmldesigner/components/itemlibrary/itemlibrarymodel.cpp
index 321dd5713cac9591e9d58cbc86b7e4c6e4652553..416d69cc369b969bdb2cde7f7ea6cf817068346b 100644
--- a/src/plugins/qmldesigner/components/itemlibrary/itemlibrarymodel.cpp
+++ b/src/plugins/qmldesigner/components/itemlibrary/itemlibrarymodel.cpp
@@ -386,7 +386,8 @@ bool ItemLibraryModel::isItemVisible(int itemLibId)
 
 QString entryToImport(const ItemLibraryEntry &entry)
 {
-    return entry.requiredImport() + " " + QString::number(entry.majorVersion()) + "." + QString::number(entry.minorVersion());
+    return entry.requiredImport() + QLatin1Char(' ') + QString::number(entry.majorVersion())
+            + QLatin1Char('.') + QString::number(entry.minorVersion());
 }
 
 void ItemLibraryModel::update(ItemLibraryInfo *itemLibraryInfo, Model *model)
@@ -401,7 +402,7 @@ void ItemLibraryModel::update(ItemLibraryInfo *itemLibraryInfo, Model *model)
     QStringList imports;
     foreach (const Import &import, model->imports())
         if (import.isLibraryImport())
-            imports << import.url() + " " + import.version();
+            imports << import.url() + QLatin1Char(' ') + import.version();
 
     foreach (ItemLibraryEntry entry, itemLibraryInfo->entries()) {
 
diff --git a/src/plugins/qmldesigner/components/navigator/navigatortreemodel.cpp b/src/plugins/qmldesigner/components/navigator/navigatortreemodel.cpp
index 1e838ab3417da1c9cb28f1e75a5789d9687d14d8..b6eab6a264de42bdcf4dc43fba0983ba429a3747 100644
--- a/src/plugins/qmldesigner/components/navigator/navigatortreemodel.cpp
+++ b/src/plugins/qmldesigner/components/navigator/navigatortreemodel.cpp
@@ -573,7 +573,7 @@ QString NavigatorTreeModel::qmlTypeInQtContainer(const QString &qtContainerType)
 {
     QString typeName(qtContainerType);
     if (typeName.startsWith("QDeclarativeListProperty<") &&
-        typeName.endsWith(">")) {
+        typeName.endsWith('>')) {
         typeName.remove(0, 25);
         typeName.chop(1);
     }
diff --git a/src/plugins/qmldesigner/components/propertyeditor/propertyeditor.cpp b/src/plugins/qmldesigner/components/propertyeditor/propertyeditor.cpp
index b507875842dbeff9b27a161607e4a6e56dc9ac42..6bbede3f8ea2ac7adc599275d7ab18ff95ec1eea 100644
--- a/src/plugins/qmldesigner/components/propertyeditor/propertyeditor.cpp
+++ b/src/plugins/qmldesigner/components/propertyeditor/propertyeditor.cpp
@@ -581,7 +581,7 @@ QString templateGeneration(NodeMetaInfo type, NodeMetaInfo superType, const QmlO
 
     foreach (const QString &name, orderedList) {
         QString properName = name;
-        properName.replace(".", "_");
+        properName.replace('.', '_');
 
         QString typeName = type.propertyTypeName(name);
         //alias resolution only possible with instance
diff --git a/src/plugins/qmldesigner/components/stateseditor/stateseditorimageprovider.cpp b/src/plugins/qmldesigner/components/stateseditor/stateseditorimageprovider.cpp
index f212f7ae516bf6f56332de6a8ecdb764da0ccc69..8fe5175f18d66d92905023ed1c59802724ae6494 100644
--- a/src/plugins/qmldesigner/components/stateseditor/stateseditorimageprovider.cpp
+++ b/src/plugins/qmldesigner/components/stateseditor/stateseditorimageprovider.cpp
@@ -55,7 +55,7 @@ QImage StatesEditorImageProvider::requestImage(const QString &id, QSize *size, c
     if (newSize.isEmpty())
         newSize = QSize (100, 100);
 
-    QString imageId = id.split("-").first();
+    QString imageId = id.split(QLatin1Char('-')).first();
     QImage image;
 
     if (imageId == "baseState") {
diff --git a/src/plugins/qmldesigner/designercore/filemanager/qmlrewriter.cpp b/src/plugins/qmldesigner/designercore/filemanager/qmlrewriter.cpp
index baa08fbc348b88237532c8d2eeaee339ab40133e..c110eac6e619ee4577b4f4714c4f2392add2c5dd 100644
--- a/src/plugins/qmldesigner/designercore/filemanager/qmlrewriter.cpp
+++ b/src/plugins/qmldesigner/designercore/filemanager/qmlrewriter.cpp
@@ -283,7 +283,7 @@ void QMLRewriter::includeLeadingEmptyLine(int &start) const
 // FIXME: duplicate code in the QmlJS::Rewriter class, remove this
 UiObjectMemberList *QMLRewriter::searchMemberToInsertAfter(UiObjectMemberList *members, const QStringList &propertyOrder)
 {
-    const int objectDefinitionInsertionPoint = propertyOrder.indexOf(QString::null);
+    const int objectDefinitionInsertionPoint = propertyOrder.indexOf(QString());
 
     UiObjectMemberList *lastObjectDef = 0;
     UiObjectMemberList *lastNonObjectDef = 0;
diff --git a/src/plugins/qmldesigner/designercore/include/nodeinstanceview.h b/src/plugins/qmldesigner/designercore/include/nodeinstanceview.h
index 0f458188f2b6ed9fc991ee15a53ee79392f43119..987d2cfc00ed788031732dfb7c583c53d4bd96e2 100644
--- a/src/plugins/qmldesigner/designercore/include/nodeinstanceview.h
+++ b/src/plugins/qmldesigner/designercore/include/nodeinstanceview.h
@@ -81,7 +81,7 @@ class CORESHARED_EXPORT NodeInstanceView : public AbstractView, public NodeInsta
 public:
     typedef QWeakPointer<NodeInstanceView> Pointer;
 
-    NodeInstanceView(QObject *parent = 0, NodeInstanceServerInterface::RunModus runModus = NodeInstanceServerInterface::NormalModus);
+    explicit NodeInstanceView(QObject *parent = 0, NodeInstanceServerInterface::RunModus runModus = NodeInstanceServerInterface::NormalModus);
     ~NodeInstanceView();
 
     void modelAttached(Model *model);
diff --git a/src/plugins/qmldesigner/designercore/instances/nodeinstanceserver.cpp b/src/plugins/qmldesigner/designercore/instances/nodeinstanceserver.cpp
index febfbe912443ababefb74588e8f4910e52fef620..04519ffb5b96717832dc76eea788a941bd7c9945 100644
--- a/src/plugins/qmldesigner/designercore/instances/nodeinstanceserver.cpp
+++ b/src/plugins/qmldesigner/designercore/instances/nodeinstanceserver.cpp
@@ -353,12 +353,12 @@ void NodeInstanceServer::addImports(const QVector<AddImportContainer> &container
             importStatement += container.url().toString();
 
         if (!container.version().isEmpty())
-            importStatement += " " + container.version();
+            importStatement += ' ' + container.version();
 
         if (!container.alias().isEmpty())
             importStatement += " as " + container.alias();
 
-        importStatement.append("\n");
+        importStatement.append('\n');
 
         if (!m_importList.contains(importStatement))
             m_importList.append(importStatement);
diff --git a/src/plugins/qmldesigner/designercore/instances/nodeinstancesignalspy.cpp b/src/plugins/qmldesigner/designercore/instances/nodeinstancesignalspy.cpp
index 5305cf0917b895219b027d1deae46397e7c781de..dddab6af8f6a180a2c2cd278bdc5bab1b40a8067 100644
--- a/src/plugins/qmldesigner/designercore/instances/nodeinstancesignalspy.cpp
+++ b/src/plugins/qmldesigner/designercore/instances/nodeinstancesignalspy.cpp
@@ -74,7 +74,7 @@ void NodeInstanceSignalSpy::registerObject(QObject *spiedObject, const QString &
                  && QDeclarativeMetaType::isQObject(metaProperty.userType())) {
                   QObject *propertyObject = QDeclarativeMetaType::toQObject(metaProperty.read(spiedObject));
                   if (propertyObject)
-                      registerObject(propertyObject, prefix + metaProperty.name() + ".");
+                      registerObject(propertyObject, prefix + metaProperty.name() + QLatin1Char('.'));
              } else if (metaProperty.hasNotifySignal()) {
                  QMetaMethod metaMethod = metaProperty.notifySignal();
                  bool isConnecting = QMetaObject::connect(spiedObject, metaMethod.methodIndex(), this, methodeOffset, Qt::DirectConnection);
@@ -90,7 +90,7 @@ void NodeInstanceSignalSpy::registerObject(QObject *spiedObject, const QString &
                  && QDeclarativeMetaType::isQObject(metaProperty.userType())) {
                  QObject *propertyObject = QDeclarativeMetaType::toQObject(metaProperty.read(spiedObject));
                  if (propertyObject)
-                     registerObject(propertyObject, prefix + metaProperty.name() + "/");
+                     registerObject(propertyObject, prefix + metaProperty.name() + QLatin1Char('/'));
              }
 
              // search recursive in objects list
@@ -101,7 +101,7 @@ void NodeInstanceSignalSpy::registerObject(QObject *spiedObject, const QString &
                      for (int i = 0; i < list.count(); i++) {
                          QObject *propertyObject = list.at(i);
                          if (propertyObject)
-                             registerObject(propertyObject, prefix + metaProperty.name() + "/");
+                             registerObject(propertyObject, prefix + metaProperty.name() + QLatin1Char('/'));
                      }
                  }
              }
diff --git a/src/plugins/qmldesigner/designercore/metainfo/nodemetainfo.cpp b/src/plugins/qmldesigner/designercore/metainfo/nodemetainfo.cpp
index baebcabe2b7fd8261aace39420c042b885f2b985..fd456bcdae31030216e60c373e9948af98f0c07b 100644
--- a/src/plugins/qmldesigner/designercore/metainfo/nodemetainfo.cpp
+++ b/src/plugins/qmldesigner/designercore/metainfo/nodemetainfo.cpp
@@ -99,13 +99,13 @@ public:
     {
         const Interpreter::ASTPropertyReference *ref = dynamic_cast<const Interpreter::ASTPropertyReference*>(value);
         if (ref) {
-            QString type = "unkown";
+            QString type = "unknown";
             if (ref->ast()->memberType)
                 type = ref->ast()->memberType->asString();
             m_properties.append(qMakePair(name, type));
         } else {
             if (const Interpreter::QmlObjectValue * ov = dynamic_cast<const Interpreter::QmlObjectValue *>(value)) {
-                QString qualifiedTypeName = ov->packageName().isEmpty() ? ov->className() : ov->packageName() + "/" + ov->className();
+                QString qualifiedTypeName = ov->packageName().isEmpty() ? ov->className() : ov->packageName() + '/' + ov->className();
                 m_properties.append(qMakePair(name, qualifiedTypeName));
             } else {
                 Interpreter::TypeId typeId;
@@ -158,11 +158,11 @@ QStringList prototypes(const Interpreter::ObjectValue *ov, LookupContext::Ptr co
         const Interpreter::QmlObjectValue * qmlValue = dynamic_cast<const Interpreter::QmlObjectValue *>(ov);
         if (qmlValue) {
             if (versions) {
-                list << qmlValue->packageName() + "/" + qmlValue->className() +
-                " " + QString::number(qmlValue->version().majorVersion()) +
-                "." + QString::number(qmlValue->version().minorVersion());
+                list << qmlValue->packageName() + '/' + qmlValue->className() +
+                ' ' + QString::number(qmlValue->version().majorVersion()) +
+                '.' + QString::number(qmlValue->version().minorVersion());
             } else {
-                list << qmlValue->packageName() + "/" + qmlValue->className();
+                list << qmlValue->packageName() + '/' + qmlValue->className();
             }
         } else {
             if (versions) {
@@ -385,7 +385,7 @@ QHash<QString, NodeMetaInfoPrivate::Pointer> NodeMetaInfoPrivate::m_nodeMetaInfo
 
 static inline QString stringIdentifier( const QString &type, int maj, int min)
 {
-    return type + QString::number(maj) + "_" + QString::number(min);
+    return type + QString::number(maj) + '_' + QString::number(min);
 }
 
 NodeMetaInfoPrivate::Pointer NodeMetaInfoPrivate::create(Model *model, const QString &type, int maj, int min)
@@ -492,8 +492,9 @@ bool NodeMetaInfoPrivate::isPropertyWritable(const QString &propertyName) const
         return false;
 
     if (propertyName.contains('.')) {
-        const QString objectName = propertyName.split(".").first();
-        const QString rawPropertyName = propertyName.split(".").last();
+        const QStringList parts = propertyName.split('.');
+        const QString objectName = parts.first();
+        const QString rawPropertyName = parts.last();
         const QString objectType = propertyType(objectName);
 
         if (isValueType(objectType)) {
@@ -523,8 +524,9 @@ bool NodeMetaInfoPrivate::isPropertyList(const QString &propertyName) const
         return false;
 
     if (propertyName.contains('.')) {
-        const QString objectName = propertyName.split(".").first();
-        const QString rawPropertyName = propertyName.split(".").last();
+        const QStringList parts = propertyName.split('.');
+        const QString objectName = parts.first();
+        const QString rawPropertyName = parts.last();
         const QString objectType = propertyType(objectName);
 
         if (isValueType(objectType)) {
@@ -550,8 +552,9 @@ bool NodeMetaInfoPrivate::isPropertyPointer(const QString &propertyName) const
         return false;
 
     if (propertyName.contains('.')) {
-        const QString objectName = propertyName.split(".").first();
-        const QString rawPropertyName = propertyName.split(".").last();
+        const QStringList parts = propertyName.split('.');
+        const QString objectName = parts.first();
+        const QString rawPropertyName = parts.last();
         const QString objectType = propertyType(objectName);
 
         if (isValueType(objectType)) {
@@ -577,8 +580,9 @@ bool NodeMetaInfoPrivate::isPropertyEnum(const QString &propertyName) const
         return false;
 
     if (propertyName.contains('.')) {
-        const QString objectName = propertyName.split(".").first();
-        const QString rawPropertyName = propertyName.split(".").last();
+        const QStringList parts = propertyName.split('.');
+        const QString objectName = parts.first();
+        const QString rawPropertyName = parts.last();
         const QString objectType = propertyType(objectName);
 
         if (isValueType(objectType)) {
@@ -612,8 +616,9 @@ QString NodeMetaInfoPrivate::propertyEnumScope(const QString &propertyName) cons
         return QString();
 
     if (propertyName.contains('.')) {
-        const QString objectName = propertyName.split(".").first();
-        const QString rawPropertyName = propertyName.split(".").last();
+        const QStringList parts = propertyName.split('.');
+        const QString objectName = parts.first();
+        const QString rawPropertyName = parts.last();
         const QString objectType = propertyType(objectName);
 
         if (isValueType(objectType)) {
@@ -797,7 +802,7 @@ void NodeMetaInfoPrivate::setupPrototypes()
             description.minorVersion = qmlValue->version().minorVersion();
             description.majorVersion = qmlValue->version().majorVersion();
             if (!qmlValue->packageName().isEmpty())
-                description.className = qmlValue->packageName() + "/" + description.className;
+                description.className = qmlValue->packageName() + '/' + description.className;
             m_prototypes.append(description);
         } else {
             if (lookupContext()->context()->lookupType(document(), QStringList() << ov->className()))
diff --git a/src/plugins/qmldesigner/designercore/model/paster.cpp b/src/plugins/qmldesigner/designercore/model/paster.cpp
index aed44925843e85b64eca410cf3e894c08b61c329..ae37881034f634d7bb8ed0078ee6c100a9939502 100644
--- a/src/plugins/qmldesigner/designercore/model/paster.cpp
+++ b/src/plugins/qmldesigner/designercore/model/paster.cpp
@@ -69,7 +69,7 @@ public:
 
     bool operator()(QmlJS::AST::UiProgram *sourceAST) {
         m_inStates = false;
-        m_stateName = QString();
+        m_stateName.clear();
 
         Node::accept(sourceAST->imports, this);
 
diff --git a/src/plugins/qmldesigner/designercore/model/qmltextgenerator.cpp b/src/plugins/qmldesigner/designercore/model/qmltextgenerator.cpp
index ed1a07113b977d383a8f0dab911eb835db4f50c6..069e059ed1785c04f97fb71da1819980eecb0bfa 100644
--- a/src/plugins/qmldesigner/designercore/model/qmltextgenerator.cpp
+++ b/src/plugins/qmldesigner/designercore/model/qmltextgenerator.cpp
@@ -138,7 +138,7 @@ QString QmlTextGenerator::toQml(const ModelNode &node, int indentDepth) const
     QString type = node.type();
     QString url;
     if (type.contains('/')) {
-        QStringList nameComponents = type.split("/");
+        const QStringList nameComponents = type.split('/');
         url = nameComponents.first();
         type = nameComponents.last();
     }
@@ -158,7 +158,7 @@ QString QmlTextGenerator::toQml(const ModelNode &node, int indentDepth) const
     QString result;
 
     if (!alias.isEmpty())
-        result = alias + ".";
+        result = alias + '.';
 
     result += type;
     result += QLatin1String(" {\n");
diff --git a/src/plugins/qmldesigner/designercore/model/viewlogger.cpp b/src/plugins/qmldesigner/designercore/model/viewlogger.cpp
index 253ed1f28f7d70092404c1dbcd02225a7e11d2b3..30f3028a5746afc5ce155df8c957e6d4b1c0ca9d 100644
--- a/src/plugins/qmldesigner/designercore/model/viewlogger.cpp
+++ b/src/plugins/qmldesigner/designercore/model/viewlogger.cpp
@@ -73,9 +73,10 @@ ViewLogger::ViewLogger(QObject *parent)
 #else
     const QString tempPath = QDir::tempPath();
 #endif
-
-    QTemporaryFile *temporaryFile = new QTemporaryFile(tempPath + QString("/qmldesigner-logger-%1-XXXXXX.txt").arg(QDateTime::currentDateTime().toString(Qt::ISODate).replace(":", "-")), this);
-
+    const QString path = tempPath + QString("/qmldesigner-logger-%1-XXXXXX.txt").
+                         arg(QDateTime::currentDateTime().toString(Qt::ISODate).
+                         replace(':', '-'));
+    QTemporaryFile *temporaryFile = new QTemporaryFile(path, this);
     temporaryFile->setAutoRemove(false);
     if (temporaryFile->open()) {
         qDebug() << "QmlDesigner: Log file is:" << temporaryFile->fileName();
diff --git a/src/plugins/qmljseditor/qmljscomponentfromobjectdef.cpp b/src/plugins/qmljseditor/qmljscomponentfromobjectdef.cpp
index 8bcf2f47e81adbfe94c0afbe422128eea7c0d442..b5cf72bdd762c52b8295bc34f2b8715392249e31 100644
--- a/src/plugins/qmljseditor/qmljscomponentfromobjectdef.cpp
+++ b/src/plugins/qmljseditor/qmljscomponentfromobjectdef.cpp
@@ -55,13 +55,13 @@ static QString toString(Statement *statement)
 {
     ExpressionStatement *expStmt = cast<ExpressionStatement *>(statement);
     if (!expStmt)
-        return QString::null;
+        return QString();
     if (IdentifierExpression *idExp = cast<IdentifierExpression *>(expStmt->expression)) {
         return idExp->name->asString();
     } else if (StringLiteral *strExp = cast<StringLiteral *>(expStmt->expression)) {
         return strExp->value->asString();
     }
-    return QString::null;
+    return QString();
 }
 
 static QString getIdProperty(UiObjectDefinition *def)
diff --git a/src/plugins/qmljseditor/qmljscomponentnamedialog.cpp b/src/plugins/qmljseditor/qmljscomponentnamedialog.cpp
index 7bca243a25b3d25b00cda564bbd8cfdfc4e0c371..2f8f41bba89a672f43c7c2ce40929940dfd16c34 100644
--- a/src/plugins/qmljseditor/qmljscomponentnamedialog.cpp
+++ b/src/plugins/qmljseditor/qmljscomponentnamedialog.cpp
@@ -100,5 +100,5 @@ QString ComponentNameDialog::isValid() const
     if (path.isEmpty() || !QFileInfo(path).isDir())
         return tr("Invalid path");
 
-    return QString::null;
+    return QString();
 }
diff --git a/src/plugins/qmlprojectmanager/qmlprojectnodes.cpp b/src/plugins/qmlprojectmanager/qmlprojectnodes.cpp
index 2ab2548cc2d3823d6293f97d862ce03b967d8b39..6cf057442bd96d1fd8f1dab164e1f2c56c77b551 100644
--- a/src/plugins/qmlprojectmanager/qmlprojectnodes.cpp
+++ b/src/plugins/qmlprojectmanager/qmlprojectnodes.cpp
@@ -151,7 +151,7 @@ ProjectExplorer::FolderNode *QmlProjectNode::findOrCreateFolderByName(const QStr
     else if (FolderNode *folder = m_folderByName.value(folderName))
         return folder;
 
-    FolderNode *folder = new FolderNode(baseDir + "/" + folderName);
+    FolderNode *folder = new FolderNode(baseDir + '/' + folderName);
     folder->setDisplayName(component);
 
     m_folderByName.insert(folderName, folder);
diff --git a/src/plugins/qt4projectmanager/qt-desktop/qt4desktoptargetfactory.cpp b/src/plugins/qt4projectmanager/qt-desktop/qt4desktoptargetfactory.cpp
index 7c458ab1a8eea5756391bc4fcfcbe9b45b31b885..5a9b421b0ca301828d53861dddc1eff31cd47230 100644
--- a/src/plugins/qt4projectmanager/qt-desktop/qt4desktoptargetfactory.cpp
+++ b/src/plugins/qt4projectmanager/qt-desktop/qt4desktoptargetfactory.cpp
@@ -131,7 +131,7 @@ QString Qt4DesktopTargetFactory::defaultShadowBuildDirectory(const QString &proj
 QList<BuildConfigurationInfo> Qt4DesktopTargetFactory::availableBuildConfigurations(const QString &id, const QString &proFilePath, const QtVersionNumber &minimumQtVersion)
 {
     Q_ASSERT(id == Constants::DESKTOP_TARGET_ID);
-    QList<BuildConfigurationInfo> infos;
+    QList<BuildConfigurationInfo> infoList;
     QList<QtVersion *> knownVersions = QtVersionManager::instance()->versionsForTargetId(id, minimumQtVersion);
 
     foreach (QtVersion *version, knownVersions) {
@@ -140,10 +140,10 @@ QList<BuildConfigurationInfo> Qt4DesktopTargetFactory::availableBuildConfigurati
         QtVersion::QmakeBuildConfigs config = version->defaultBuildConfig();
 
         QString dir = defaultShadowBuildDirectory(Qt4Project::defaultTopLevelBuildDirectory(proFilePath), id);
-        infos.append(BuildConfigurationInfo(version, config, QString(), dir));
-        infos.append(BuildConfigurationInfo(version, config ^ QtVersion::DebugBuild, QString(), dir));
+        infoList.append(BuildConfigurationInfo(version, config, QString(), dir));
+        infoList.append(BuildConfigurationInfo(version, config ^ QtVersion::DebugBuild, QString(), dir));
     }
-    return infos;
+    return infoList;
 }
 
 Qt4TargetSetupWidget *Qt4DesktopTargetFactory::createTargetSetupWidget(const QString &id, const QString &proFilePath, const QtVersionNumber &number, bool importEnabled, QList<BuildConfigurationInfo> importInfos)
diff --git a/src/plugins/qt4projectmanager/qt-s60/s60certificateinfo.cpp b/src/plugins/qt4projectmanager/qt-s60/s60certificateinfo.cpp
index e63d1e0b1e5f5ff0ef7219bda04992717ab56fa6..39d15a252ef3cd042bbe2b99b2a0d9ac0dbb425a 100644
--- a/src/plugins/qt4projectmanager/qt-s60/s60certificateinfo.cpp
+++ b/src/plugins/qt4projectmanager/qt-s60/s60certificateinfo.cpp
@@ -135,8 +135,8 @@ QStringList createHtmlCapabilityList(uint capabilities)
         while (i.hasNext()) {
             i.next();
             if (i.key() == capabilitySet[j].value) {
-                foreach (QString capability, i.value()) {
-                    result << QString("<font color=\"%1\">%2</font>")
+                foreach (const QString &capability, i.value()) {
+                    result << QString::fromAscii("<font color=\"%1\">%2</font>")
                               .arg(capabilitySet[j].color).arg(capability);
                 }
                 break;
diff --git a/src/plugins/qt4projectmanager/qt-s60/s60createpackagestep.cpp b/src/plugins/qt4projectmanager/qt-s60/s60createpackagestep.cpp
index 445d2c96292a1cd5be9c595426cfb965de25fc5b..d2ac2e15e2157b973c77e67b6211cb036edf94ab 100644
--- a/src/plugins/qt4projectmanager/qt-s60/s60createpackagestep.cpp
+++ b/src/plugins/qt4projectmanager/qt-s60/s60createpackagestep.cpp
@@ -708,10 +708,10 @@ void S60CreatePackageStep::resetPassphrases()
 {
     m_passphrases->beginGroup("keys");
     QStringList keys = m_passphrases->allKeys();
-    foreach (QString key, keys) {
-        m_passphrases->setValue(key, "");
+    foreach (const QString &key, keys) {
+        m_passphrases->setValue(key, QString());
     }
-    m_passphrases->remove("");
+    m_passphrases->remove(QString());
     m_passphrases->endGroup();
 }
 
diff --git a/src/plugins/qt4projectmanager/qt-s60/s60devicerunconfiguration.h b/src/plugins/qt4projectmanager/qt-s60/s60devicerunconfiguration.h
index 4998c1bf633f0f962c9042eecfb2430b40d60812..8536bdd923038b1c04ef19c2f7b8df343485b4a6 100644
--- a/src/plugins/qt4projectmanager/qt-s60/s60devicerunconfiguration.h
+++ b/src/plugins/qt4projectmanager/qt-s60/s60devicerunconfiguration.h
@@ -101,7 +101,7 @@ private slots:
 
 private:
     void ctor();
-    void handleParserState(bool sucess);
+    void handleParserState(bool success);
 
     QString m_proFilePath;
     QString m_commandLineArguments;
diff --git a/src/plugins/qt4projectmanager/qt-s60/s60symbiancertificate.cpp b/src/plugins/qt4projectmanager/qt-s60/s60symbiancertificate.cpp
index 91f20bfa6afc9ab9c0e83719d2c1c266b985b0ca..3cafa4d10508de1e4322e09612f97f84085d785f 100644
--- a/src/plugins/qt4projectmanager/qt-s60/s60symbiancertificate.cpp
+++ b/src/plugins/qt4projectmanager/qt-s60/s60symbiancertificate.cpp
@@ -336,7 +336,7 @@ public:
 
     /**
    * Get a value for a specific subject_info parameter name.
-   * @param name the name of the paramter to look up. Possible names are
+   * @param name the name of the parameter to look up. Possible names are
    * "X509.Certificate.version", "X509.Certificate.serial",
    * "X509.Certificate.start", "X509.Certificate.end",
    * "X509.Certificate.v2.key_id", "X509.Certificate.public_key",
diff --git a/src/plugins/qt4projectmanager/qt4nodes.cpp b/src/plugins/qt4projectmanager/qt4nodes.cpp
index a7c416546bb369333cc34ef7a94c47e7bcaac306..e48a3de6a6f795850970b7a8063ebf9dedb2da6b 100644
--- a/src/plugins/qt4projectmanager/qt4nodes.cpp
+++ b/src/plugins/qt4projectmanager/qt4nodes.cpp
@@ -363,7 +363,7 @@ struct InternalNode
                 // replace i.value() by i.value()->subnodes.begin()
                 QString key = i.value()->subnodes.begin().key();
                 InternalNode *keep = i.value()->subnodes.value(key);
-                keep->displayName = i.value()->displayName + "/" + keep->displayName;
+                keep->displayName = i.value()->displayName + '/' + keep->displayName;
                 newSubnodes.insert(key, keep);
                 i.value()->subnodes.clear();
                 delete i.value();
@@ -556,9 +556,9 @@ void Qt4PriFileNode::update(ProFile *includeFileExact, ProFileReader *readerExac
 
 
     for (int i=0; i < folders.size(); ++i) {
-        QFileInfo fi(folders.at(i));
+        const QFileInfo fi(folders.at(i));
         if (fi.isRelative())
-            folders[i] = projectDir + "/" + folders.at(i);
+            folders[i] = projectDir + '/' + folders.at(i);
     }
 
 
@@ -1287,7 +1287,7 @@ QStringList Qt4ProFileNode::symbianCapabilities() const
 
     foreach (const QString &cap, m_varValues[SymbianCapabilities]) {
         QString capability = cap.toLower();
-        if (capability.startsWith("-")) {
+        if (capability.startsWith('-')) {
             lowerCasedResult.removeAll(capability.mid(1));
         } else if (capability == "all") {
             foreach (const QString &a, all)
@@ -1299,7 +1299,7 @@ QStringList Qt4ProFileNode::symbianCapabilities() const
     }
     QStringList result; //let's make the result pretty
     int index = -1;
-    foreach (QString lowerCase, lowerCasedResult) {
+    foreach (const QString &lowerCase, lowerCasedResult) {
         for (int i = 0; i < all.count(); ++i) {
             index = -1;
             if (QString::compare(lowerCase, all.at(i),
@@ -1916,7 +1916,7 @@ QString Qt4ProFileNode::uiDirPath(ProFileReader *reader) const
 {
     QString path = reader->value("UI_DIR");
     if (QFileInfo(path).isRelative())
-        path = QDir::cleanPath(buildDir() + "/" + path);
+        path = QDir::cleanPath(buildDir() + '/' + path);
     return path;
 }
 
@@ -1924,7 +1924,7 @@ QString Qt4ProFileNode::mocDirPath(ProFileReader *reader) const
 {
     QString path = reader->value("MOC_DIR");
     if (QFileInfo(path).isRelative())
-        path = QDir::cleanPath(buildDir() + "/" + path);
+        path = QDir::cleanPath(buildDir() + '/' + path);
     return path;
 }
 
diff --git a/src/plugins/qt4projectmanager/qt4project.cpp b/src/plugins/qt4projectmanager/qt4project.cpp
index 41b4f4ede0360b280117b09679723f1a1e8865ce..bbfedd800263044db44267bdc3c390c6116736f8 100644
--- a/src/plugins/qt4projectmanager/qt4project.cpp
+++ b/src/plugins/qt4projectmanager/qt4project.cpp
@@ -1087,8 +1087,9 @@ QSet<QString> CentralizedFolderWatcher::recursiveDirs(const QString &folder)
     QDir dir(folder);
     QStringList list = dir.entryList(QDir::Dirs | QDir::NoSymLinks | QDir::NoDotAndDotDot);
     foreach (const QString &f, list) {
-        result.insert(folder + f + "/");
-        result += recursiveDirs(folder + f + "/");
+        const QString a = folder + f + '/';
+        result.insert(a);
+        result += recursiveDirs(a);
     }
     return result;
 }
diff --git a/src/plugins/qt4projectmanager/qt4target.cpp b/src/plugins/qt4projectmanager/qt4target.cpp
index db5653702e464b563ca04e4c4ce03be516e8bc59..54b1798a9dcb335959f89a14ca4bc77218f8f8ea 100644
--- a/src/plugins/qt4projectmanager/qt4target.cpp
+++ b/src/plugins/qt4projectmanager/qt4target.cpp
@@ -421,7 +421,7 @@ QString Qt4DefaultTargetSetupWidget::displayNameFrom(const BuildConfigurationInf
             //: release build
             buildType = tr("release");
     }
-    return info.version->displayName() + " " + buildType;
+    return info.version->displayName() + ' ' + buildType;
 }
 
 void Qt4DefaultTargetSetupWidget::setProFilePath(const QString &proFilePath)
diff --git a/src/plugins/qt4projectmanager/qtversionmanager.cpp b/src/plugins/qt4projectmanager/qtversionmanager.cpp
index 55558b2f6f61af83366bd0905d58dbb5fb2ef17f..539544d34005a53bf397a85c5ace5596f65a5e06 100644
--- a/src/plugins/qt4projectmanager/qtversionmanager.cpp
+++ b/src/plugins/qt4projectmanager/qtversionmanager.cpp
@@ -864,7 +864,7 @@ void QtVersion::setQMakeCommand(const QString& qmakeCommand)
     m_abiUpToDate = false;
     // TODO do i need to optimize this?
     m_versionInfoUpToDate = false;
-    m_qtVersionString = QString();
+    m_qtVersionString.clear();
     updateSourcePath();
 }
 
diff --git a/src/plugins/qtestlib/qtestlibplugin.cpp b/src/plugins/qtestlib/qtestlibplugin.cpp
index eed544a6149bc4be849714e36f864d19509f6a79..69893ff33fee376596169204bd290d2aab24f643 100644
--- a/src/plugins/qtestlib/qtestlibplugin.cpp
+++ b/src/plugins/qtestlib/qtestlibplugin.cpp
@@ -151,7 +151,7 @@ void QTestLibPlugin::projectRunHook(ProjectExplorer::Project *proj)
     if (!proj)
         return;
 
-    m_projectDirectory = QString();
+    m_projectDirectory.clear();
     //NBS proj->setExtraApplicationRunArguments(QStringList());
     //NBS proj->setCustomApplicationOutputHandler(0);
 
diff --git a/src/plugins/texteditor/basetextdocumentlayout.h b/src/plugins/texteditor/basetextdocumentlayout.h
index ff97c7fc333e60d37830277dd4f189a95a441459..8a2b640836ec387c751057f30da2abb908a544b9 100644
--- a/src/plugins/texteditor/basetextdocumentlayout.h
+++ b/src/plugins/texteditor/basetextdocumentlayout.h
@@ -120,10 +120,10 @@ public:
      * indention level (or higher).
      */
     inline void setFoldingIndent(int indent) { m_foldingIndent = indent; }
-    // Set whether the first charater of the folded region will show when the code is folded.
+    // Set whether the first character of the folded region will show when the code is folded.
     inline void setFoldingStartIncluded(bool included) { m_foldingStartIncluded = included; }
     inline bool foldingStartIncluded() const { return m_foldingStartIncluded; }
-    // Set whether the last charater of the folded region will show when the code is folded.
+    // Set whether the last character of the folded region will show when the code is folded.
     inline void setFoldingEndIncluded(bool included) { m_foldingEndIncluded = included; }
     inline bool foldingEndIncluded() const { return m_foldingEndIncluded; }
     inline int lexerState() const { return m_lexerState; }
diff --git a/src/plugins/texteditor/icompletioncollector.cpp b/src/plugins/texteditor/icompletioncollector.cpp
index 98a8ed180f5d73249aaad6fcfcb46c6c05459e80..e378a4c482bcec98d88b826a501d8b49d9071967 100644
--- a/src/plugins/texteditor/icompletioncollector.cpp
+++ b/src/plugins/texteditor/icompletioncollector.cpp
@@ -208,7 +208,7 @@ void ICompletionCollector::filter(const QList<TextEditor::CompletionItem> &items
     }
     const QRegExp regExp(keyRegExp);
 
-    foreach (TextEditor::CompletionItem item, items)
+    foreach (const TextEditor::CompletionItem &item, items)
         if (regExp.indexIn(item.text) == 0)
             filteredItems->append(item);
 }
diff --git a/src/plugins/texteditor/snippets/snippet.h b/src/plugins/texteditor/snippets/snippet.h
index 2cb2307f876573f3e4020d726191162d31202901..92e6d61c4d3a9680d3c6fa353234b4a32c187d65 100644
--- a/src/plugins/texteditor/snippets/snippet.h
+++ b/src/plugins/texteditor/snippets/snippet.h
@@ -44,7 +44,7 @@ namespace TextEditor {
 class TEXTEDITOR_EXPORT Snippet
 {
 public:
-    Snippet(const QString &groupId = QString(), const QString &id = QString());
+    explicit Snippet(const QString &groupId = QString(), const QString &id = QString());
     ~Snippet();
 
     const QString &id() const;
diff --git a/src/shared/qtlockedfile/qtlockedfile_win.cpp b/src/shared/qtlockedfile/qtlockedfile_win.cpp
index 7c4b53af735a6d2b81487927dab06b63772c4914..20d2bc60c19ba71be811842e3de9d66798757f72 100644
--- a/src/shared/qtlockedfile/qtlockedfile_win.cpp
+++ b/src/shared/qtlockedfile/qtlockedfile_win.cpp
@@ -53,7 +53,7 @@ static QString errorCodeToString(DWORD errorCode)
     if (data != 0)
         LocalFree(data);
 
-    if (result.endsWith("\n"))
+    if (result.endsWith('\n'))
         result.truncate(result.length() - 1);
 
     return result;
diff --git a/src/tools/qtpromaker/main.cpp b/src/tools/qtpromaker/main.cpp
index a4851218a7095cc9d3694f3744c86f769a2f9409..4c6e28cf58d116adb5a683c8f18efaaa5779a655 100644
--- a/src/tools/qtpromaker/main.cpp
+++ b/src/tools/qtpromaker/main.cpp
@@ -17,7 +17,7 @@
 // Put everything into a single project.
 static int targetDepth = 0;
 static bool forceOverWrite = false;
-static QString subProjectSeparator = "_";
+static QString subProjectSeparator = QString(QLatin1Char('_'));
 
 // FIXME: Make file classes configurable on the command line.
 static const char *defaultExtensions[] =