diff --git a/src/app/main.cpp b/src/app/main.cpp
index 583e97ce44969f81bf516fdd88935cbbd60d66ab..6e9738e847155eb6d1a3dfc189f2ffdb89012646 100644
--- a/src/app/main.cpp
+++ b/src/app/main.cpp
@@ -452,7 +452,7 @@ int main(int argc, char **argv)
         }
     }
     if (!coreplugin) {
-        QString nativePaths = QDir::toNativeSeparators(pluginPaths.join(QLatin1String(",")));
+        QString nativePaths = QDir::toNativeSeparators(pluginPaths.join(QLatin1Char(',')));
         const QString reason = QCoreApplication::translate("Application", "Could not find 'Core.pluginspec' in %1").arg(nativePaths);
         displayError(msgCoreLoadFailure(reason));
         return 1;
diff --git a/src/libs/extensionsystem/pluginmanager.cpp b/src/libs/extensionsystem/pluginmanager.cpp
index f5bcf525ea485098407f9fcb1e2c751e7c83a640..ac50369b323bfe9d5f8d82103fb31653975b6226 100644
--- a/src/libs/extensionsystem/pluginmanager.cpp
+++ b/src/libs/extensionsystem/pluginmanager.cpp
@@ -517,7 +517,7 @@ QString PluginManager::serializedArguments()
             rc += QLatin1Char(':');
             rc += ps->name();
             rc += separator;
-            rc +=  ps->arguments().join(QString(separator));
+            rc +=  ps->arguments().join(separator);
         }
     }
     if (!d->arguments.isEmpty()) {
diff --git a/src/libs/qmldebug/declarativetoolsclient.cpp b/src/libs/qmldebug/declarativetoolsclient.cpp
index a08a672f749b78c2d4a2214b118bf86867359b2e..3fae211851244db8e885c203e19d33a10de02fb1 100644
--- a/src/libs/qmldebug/declarativetoolsclient.cpp
+++ b/src/libs/qmldebug/declarativetoolsclient.cpp
@@ -465,7 +465,7 @@ void DeclarativeToolsClient::createQmlObject(const QString &qmlText,
 
     log(LogSend, cmd, QString::fromLatin1("%1 %2 [%3] %4").arg(qmlText,
                                                    QString::number(parentDebugId),
-                                                   imports.join(QLatin1String(",")), filename));
+                                                   imports.join(QLatin1Char(',')), filename));
 
     sendMessage(message);
 }
diff --git a/src/libs/qmldebug/qmltoolsclient.cpp b/src/libs/qmldebug/qmltoolsclient.cpp
index 23c238d06169fa4218007c974e3409f1a33d9ba9..c81c766613d19030760129ec5058092058780f30 100644
--- a/src/libs/qmldebug/qmltoolsclient.cpp
+++ b/src/libs/qmldebug/qmltoolsclient.cpp
@@ -112,7 +112,7 @@ void QmlToolsClient::messageReceived(const QByteArray &message)
                 }
             }
             log(LogReceive, type + ':' + event,
-                QString::fromLatin1("[%1]").arg(debugIdStrings.join(QLatin1String(","))));
+                QString::fromLatin1("[%1]").arg(debugIdStrings.join(QLatin1Char(','))));
             emit currentObjectsChanged(m_currentDebugIds);
         }
     } else {
@@ -277,7 +277,7 @@ void QmlToolsClient::createQmlObject(const QString &qmlText,
 
     log(LogSend, CREATE_OBJECT, QString::fromLatin1("%1 %2 [%3] %4").arg(qmlText,
                                                    QString::number(parentDebugId),
-                                                   imports.join(QLatin1String(",")), filename));
+                                                   imports.join(QLatin1Char(',')), filename));
 
     sendMessage(message);
 }
diff --git a/src/libs/qmljs/qmljscompletioncontextfinder.cpp b/src/libs/qmljs/qmljscompletioncontextfinder.cpp
index 5d91610474d51a5366c5aafe32ffc6b5d9f00cf6..42d12212666f0ce164d098f9cb766996bb3b5339 100644
--- a/src/libs/qmljs/qmljscompletioncontextfinder.cpp
+++ b/src/libs/qmljs/qmljscompletioncontextfinder.cpp
@@ -303,7 +303,7 @@ void CompletionContextFinder::checkImport()
 
     YY_RESTORE();
     if (m_inImport && isInLibVersionImport == 1) {
-        m_libVersion = libVersionImport.join(QLatin1String(""));
+        m_libVersion = libVersionImport.join(QString());
         if (m_libVersion.isNull())
             m_libVersion = QLatin1String("");
     } else {
diff --git a/src/libs/qmljs/qmljsdocument.cpp b/src/libs/qmljs/qmljsdocument.cpp
index 4987dd1a251a6f5ab4e861ee20204fc7d19efc86..d22e84e42ecb875458297e65bbbc845c88d22472 100644
--- a/src/libs/qmljs/qmljsdocument.cpp
+++ b/src/libs/qmljs/qmljsdocument.cpp
@@ -481,10 +481,10 @@ void Snapshot::insertLibraryInfo(const QString &path, const LibraryInfo &info)
                 --iPath;
                 if (safeName.indexIn(myPath.at(iPath)) != 0)
                     break;
-                ImportKey iKey(ImportType::Library, QStringList(myPath.mid(iPath)).join(QLatin1String(".")),
+                ImportKey iKey(ImportType::Library, QStringList(myPath.mid(iPath)).join(QLatin1Char('.')),
                                importKey.majorVersion, importKey.minorVersion);
                 cImport.possibleExports.append(Export(iKey, (iPath == 1) ? QLatin1String("/") :
-                     QStringList(myPath.mid(0, iPath)).join(QLatin1String("/")), true));
+                     QStringList(myPath.mid(0, iPath)).join(QLatin1Char('/')), true));
             }
         } else {
             QString requiredPath = QStringList(splitPath.mid(0, splitPath.size() - importKey.splitPath.size()))
@@ -512,10 +512,10 @@ void Snapshot::insertLibraryInfo(const QString &path, const LibraryInfo &info)
             --iPath;
             if (safeName.indexIn(splitPath.at(iPath)) != 0)
                 break;
-            ImportKey iKey(ImportType::Library, QStringList(splitPath.mid(iPath)).join(QLatin1String(".")),
+            ImportKey iKey(ImportType::Library, QStringList(splitPath.mid(iPath)).join(QLatin1Char('.')),
                            majorVersion, minorVersion);
             cImport.possibleExports.append(Export(iKey, (iPath == 1) ? QLatin1String("/") :
-                QStringList(splitPath.mid(0, iPath)).join(QLatin1String("/")), true));
+                QStringList(splitPath.mid(0, iPath)).join(QLatin1Char('/')), true));
         }
     }
     foreach (const QmlDirParser::Component &component, info.components()) {
diff --git a/src/libs/qmljs/qmljsimportdependencies.cpp b/src/libs/qmljs/qmljsimportdependencies.cpp
index 4b39016c949d365981d15e21bb15aecd212cf5b1..390b188724926001382acca0f645fd48d7ff1381 100644
--- a/src/libs/qmljs/qmljsimportdependencies.cpp
+++ b/src/libs/qmljs/qmljsimportdependencies.cpp
@@ -200,7 +200,7 @@ ImportKey ImportKey::flatKey() const {
 
 QString ImportKey::libraryQualifiedPath() const
 {
-    QString res = splitPath.join(QString::fromLatin1("."));
+    QString res = splitPath.join(QLatin1Char('.'));
     if (res.isEmpty() && !splitPath.isEmpty())
         return QLatin1String("");
     return res;
@@ -208,7 +208,7 @@ QString ImportKey::libraryQualifiedPath() const
 
 QString ImportKey::path() const
 {
-    QString res = splitPath.join(QString::fromLatin1("/"));
+    QString res = splitPath.join(QLatin1Char('/'));
     if (res.isEmpty() && !splitPath.isEmpty())
         return QLatin1String("/");
     return res;
@@ -442,7 +442,7 @@ QString ImportKey::toString() const
         res = path();
         break;
     case ImportType::Library:
-        res = splitPath.join(QLatin1String("."));
+        res = splitPath.join(QLatin1Char('.'));
         break;
     }
 
diff --git a/src/libs/qmljs/qmljslink.cpp b/src/libs/qmljs/qmljslink.cpp
index 76379ed3d740a3d3b8bd58b85b261c3d6a264313..5671cc1273b11d27a7c2df2125731f58d2eaefbf 100644
--- a/src/libs/qmljs/qmljslink.cpp
+++ b/src/libs/qmljs/qmljslink.cpp
@@ -431,7 +431,7 @@ Import LinkPrivate::importNonFile(Document::Ptr doc, const ImportInfo &importInf
                   "%1\n\n"
                   "For qmake projects, use the QML_IMPORT_PATH variable to add import paths.\n"
                   "For qmlproject projects, use the importPaths property to add import paths.").arg(
-                  importPaths.join(QLatin1String("\n"))));
+                  importPaths.join(QLatin1Char('\n'))));
     }
 
     return import;
diff --git a/src/libs/qmljs/qmljsplugindumper.cpp b/src/libs/qmljs/qmljsplugindumper.cpp
index 18fb1666ed1772600aa8b114f2969ea84c0e4179..687e3bedd20e51d57e9c94826ed3d874c6e554e6 100644
--- a/src/libs/qmljs/qmljsplugindumper.cpp
+++ b/src/libs/qmljs/qmljsplugindumper.cpp
@@ -241,7 +241,7 @@ static QString qmldumpErrorMessage(const QString &libraryPath, const QString &er
 static QString qmldumpFailedMessage(const QString &libraryPath, const QString &error)
 {
     QString firstLines =
-            QStringList(error.split(QLatin1Char('\n')).mid(0, 10)).join(QLatin1String("\n"));
+            QStringList(error.split(QLatin1Char('\n')).mid(0, 10)).join(QLatin1Char('\n'));
     return noTypeinfoError(libraryPath) + QLatin1String("\n\n") +
             PluginDumper::tr("Automatic type dump of QML module failed.\n"
                              "First 10 lines or errors:\n"
@@ -412,9 +412,9 @@ void PluginDumper::loadQmltypesFile(const QStringList &qmltypesFilePaths,
     if (errors.isEmpty()) {
         libraryInfo.setPluginTypeInfoStatus(LibraryInfo::TypeInfoFileDone);
     } else {
-        printParseWarnings(libraryPath, errors.join(QLatin1String("\n")));
+        printParseWarnings(libraryPath, errors.join(QLatin1Char('\n')));
         errors.prepend(tr("Errors while reading typeinfo files:"));
-        libraryInfo.setPluginTypeInfoStatus(LibraryInfo::TypeInfoFileError, errors.join(QLatin1String("\n")));
+        libraryInfo.setPluginTypeInfoStatus(LibraryInfo::TypeInfoFileError, errors.join(QLatin1Char('\n')));
     }
 
     if (!warnings.isEmpty())
diff --git a/src/libs/qmljs/qmljsreformatter.cpp b/src/libs/qmljs/qmljsreformatter.cpp
index c14c8a0d881c8f08e2e6f652f9a54805eece6a14..da7b89233fc31c19c5895476dd1f3d3d8b70b440 100644
--- a/src/libs/qmljs/qmljsreformatter.cpp
+++ b/src/libs/qmljs/qmljsreformatter.cpp
@@ -301,7 +301,7 @@ protected:
                 continue;
 
             // the extra space is to avoid // comments sticking to the 0 offset
-            QString indentLine = newContext.join(QLatin1String("\n")) + QLatin1String("\n ") + restLine;
+            QString indentLine = newContext.join(QLatin1Char('\n')) + QLatin1String("\n ") + restLine;
             int indent = tryIndent(indentLine);
 
             QList<Split> newSplits = possibleSplits.mid(i + 1);
diff --git a/src/libs/utils/buildablehelperlibrary.cpp b/src/libs/utils/buildablehelperlibrary.cpp
index a405c71aee4cd8aa177e0285bf7059e949d156e3..897be4eb7b8620e89557a63c21d254a13c717c38 100644
--- a/src/libs/utils/buildablehelperlibrary.cpp
+++ b/src/libs/utils/buildablehelperlibrary.cpp
@@ -235,7 +235,7 @@ static bool runBuildProcess(QProcess &proc,
         QString cmd = binary.toString();
         if (!args.isEmpty()) {
             cmd += QLatin1Char(' ');
-            cmd += args.join(QString(QLatin1Char(' ')));
+            cmd += args.join(QLatin1Char(' '));
         }
         *errorMessage =
                 QCoreApplication::translate("ProjectExplorer::BuildableHelperLibrary",
@@ -287,7 +287,7 @@ bool BuildableHelperLibrary::buildHelper(const BuildHelperArguments &arguments,
     log->append(newline);
     log->append(QCoreApplication::translate("ProjectExplorer::BuildableHelperLibrary",
                                             "Running %1 %2 ...\n").arg(arguments.qmakeCommand.toUserOutput(),
-                                                                       qmakeArgs.join(QLatin1String(" "))));
+                                                                       qmakeArgs.join(QLatin1Char(' '))));
 
     if (!runBuildProcess(proc, arguments.qmakeCommand, qmakeArgs, 30000, false, log, errorMessage))
         return false;
@@ -299,7 +299,7 @@ bool BuildableHelperLibrary::buildHelper(const BuildHelperArguments &arguments,
     }
     log->append(QCoreApplication::translate("ProjectExplorer::BuildableHelperLibrary",
                                             "Running %1 %2 ...\n")
-                .arg(makeFullPath.toUserOutput(), arguments.makeArguments.join(QLatin1String(" "))));
+                .arg(makeFullPath.toUserOutput(), arguments.makeArguments.join(QLatin1Char(' '))));
     if (!runBuildProcess(proc, makeFullPath, arguments.makeArguments, 120000, false, log, errorMessage))
         return false;
     return true;
diff --git a/src/libs/utils/pathlisteditor.cpp b/src/libs/utils/pathlisteditor.cpp
index ce5b02aa8d97a8744bec4cfa41be5781032019ed..e67307899a739f3f18a5309df795b81447bcc126 100644
--- a/src/libs/utils/pathlisteditor.cpp
+++ b/src/libs/utils/pathlisteditor.cpp
@@ -202,7 +202,7 @@ QStringList PathListEditor::pathList() const
 
 void PathListEditor::setPathList(const QStringList &l)
 {
-    d->edit->setPlainText(l.join(QString(QLatin1Char('\n'))));
+    d->edit->setPlainText(l.join(QLatin1Char('\n')));
 }
 
 void PathListEditor::setPathList(const QString &pathString)
diff --git a/src/plugins/android/androidconfigurations.cpp b/src/plugins/android/androidconfigurations.cpp
index b5d8fe6006ba2291b2b5e69c38ca202f57b42bb2..67fde1bef39941191a3b581f35f9ccd8c8893562 100644
--- a/src/plugins/android/androidconfigurations.cpp
+++ b/src/plugins/android/androidconfigurations.cpp
@@ -539,7 +539,7 @@ AndroidConfig::CreateAvdInfo AndroidConfig::createAVDImpl(CreateAvdInfo info, Ut
     proc.start(androidToolPath.toString(), arguments);
     if (!proc.waitForStarted()) {
         info.error = QApplication::translate("AndroidConfig", "Could not start process \"%1 %2\"")
-                .arg(androidToolPath.toString(), arguments.join(QLatin1String(" ")));
+                .arg(androidToolPath.toString(), arguments.join(QLatin1Char(' ')));
         return info;
     }
 
diff --git a/src/plugins/android/androiddeployqtstep.cpp b/src/plugins/android/androiddeployqtstep.cpp
index 9f17a76bfaea376a0786a51be753c5e6712a4e95..009ee42b56d45b7c864d859e5aabfe196c8bce06 100644
--- a/src/plugins/android/androiddeployqtstep.cpp
+++ b/src/plugins/android/androiddeployqtstep.cpp
@@ -328,18 +328,18 @@ void AndroidDeployQtStep::run(QFutureInterface<bool> &fi)
 void AndroidDeployQtStep::runCommand(const QString &program, const QStringList &arguments)
 {
     QProcess buildProc;
-    emit addOutput(tr("Package deploy: Running command \"%1 %2\".").arg(program).arg(arguments.join(QLatin1String(" "))), BuildStep::MessageOutput);
+    emit addOutput(tr("Package deploy: Running command \"%1 %2\".").arg(program).arg(arguments.join(QLatin1Char(' '))), BuildStep::MessageOutput);
     buildProc.start(program, arguments);
     if (!buildProc.waitForStarted()) {
         emit addOutput(tr("Packaging error: Could not start command \"%1 %2\". Reason: %3")
-            .arg(program).arg(arguments.join(QLatin1String(" "))).arg(buildProc.errorString()), BuildStep::ErrorMessageOutput);
+            .arg(program).arg(arguments.join(QLatin1Char(' '))).arg(buildProc.errorString()), BuildStep::ErrorMessageOutput);
         return;
     }
     if (!buildProc.waitForFinished(2 * 60 * 1000)
             || buildProc.error() != QProcess::UnknownError
             || buildProc.exitCode() != 0) {
         QString mainMessage = tr("Packaging Error: Command \"%1 %2\" failed.")
-                .arg(program).arg(arguments.join(QLatin1String(" ")));
+                .arg(program).arg(arguments.join(QLatin1Char(' ')));
         if (buildProc.error() != QProcess::UnknownError)
             mainMessage += QLatin1Char(' ') + tr("Reason: %1").arg(buildProc.errorString());
         else
diff --git a/src/plugins/android/androiddevicedialog.cpp b/src/plugins/android/androiddevicedialog.cpp
index cf42688915e1f6354d24cc5fd55e5b88be825aec..91dfc43c22cef25f1106a45718179e10f3af7f5d 100644
--- a/src/plugins/android/androiddevicedialog.cpp
+++ b/src/plugins/android/androiddevicedialog.cpp
@@ -183,7 +183,7 @@ public:
             QString lineText;
             if (node->incompatibleReason().isEmpty()) {
                 lineText = AndroidManager::androidNameForApiLevel(device.sdk) + QLatin1String("  ");
-                lineText += AndroidDeviceDialog::tr("ABI:") + device.cpuAbi.join(QLatin1String(" "));
+                lineText += AndroidDeviceDialog::tr("ABI:") + device.cpuAbi.join(QLatin1Char(' '));
             } else {
                 lineText = node->incompatibleReason();
             }
@@ -342,7 +342,7 @@ void AndroidDeviceModel::setDevices(const QVector<AndroidDeviceInfo> &devices)
                     .arg(device.serialNumber);
         } else if (!device.cpuAbi.contains(m_abi)) {
             error = AndroidDeviceDialog::tr("ABI is incompatible, device supports ABIs: %1.")
-                    .arg(device.cpuAbi.join(QLatin1String(" ")));
+                    .arg(device.cpuAbi.join(QLatin1Char(' ')));
         } else if (device.sdk < m_apiLevel) {
             error = AndroidDeviceDialog::tr("API Level of device is: %1.")
                     .arg(device.sdk);
diff --git a/src/plugins/android/androidmanager.cpp b/src/plugins/android/androidmanager.cpp
index 8ea68d46bb5ecadf4eb3416f2df37efff5ddcbe1..6419c6dca811da9103ee79db2e94ecb2ee5cb96b 100644
--- a/src/plugins/android/androidmanager.cpp
+++ b/src/plugins/android/androidmanager.cpp
@@ -416,7 +416,7 @@ static QString loadLocal(ProjectExplorer::Target *target, int apiLevel, ItemType
 
     // The next loop requires all library names to end with a ":" so we append one
     // to the end after joining.
-    localLibs = dependencyLibs.join(QLatin1String(":")) + QLatin1Char(':');
+    localLibs = dependencyLibs.join(QLatin1Char(':')) + QLatin1Char(':');
     foreach (QString replacedLib, replacedLibs)
         localLibs.remove(replacedLib + QLatin1Char(':'));
 
@@ -486,7 +486,7 @@ void AndroidManager::cleanLibsOnDevice(ProjectExplorer::Target *target)
     arguments << QLatin1String("shell") << QLatin1String("rm") << QLatin1String("-r") << QLatin1String("/data/local/tmp/qt");
     process->connect(process, SIGNAL(finished(int)), process, SLOT(deleteLater()));
     const QString adb = AndroidConfigurations::currentConfig().adbToolPath().toString();
-    Core::MessageManager::write(adb + QLatin1Char(' ') + arguments.join(QLatin1String(" ")));
+    Core::MessageManager::write(adb + QLatin1Char(' ') + arguments.join(QLatin1Char(' ')));
     process->start(adb, arguments);
     if (!process->waitForStarted(500))
         delete process;
@@ -516,7 +516,7 @@ void AndroidManager::installQASIPackage(ProjectExplorer::Target *target, const Q
 
     process->connect(process, SIGNAL(finished(int)), process, SLOT(deleteLater()));
     const QString adb = AndroidConfigurations::currentConfig().adbToolPath().toString();
-    Core::MessageManager::write(adb + QLatin1Char(' ') + arguments.join(QLatin1String(" ")));
+    Core::MessageManager::write(adb + QLatin1Char(' ') + arguments.join(QLatin1Char(' ')));
     process->start(adb, arguments);
     if (!process->waitForFinished(500))
         delete process;
diff --git a/src/plugins/beautifier/artisticstyle/artisticstylesettings.cpp b/src/plugins/beautifier/artisticstyle/artisticstylesettings.cpp
index 0b159998e70ed4974e21ef6a5a8e4f6bc962d2f8..619e37868de71097849d2002d891802cb14c7312 100644
--- a/src/plugins/beautifier/artisticstyle/artisticstylesettings.cpp
+++ b/src/plugins/beautifier/artisticstyle/artisticstylesettings.cpp
@@ -207,7 +207,7 @@ void ArtisticStyleSettings::createDocumentationFile() const
                     const QString text = QLatin1String("<p><span class=\"option\">")
                             + keys.filter(QRegExp(QLatin1String("^\\-"))).join(QLatin1String(", "))
                             + QLatin1String("</span></p><p>")
-                            + Qt::escape(docu.join(QLatin1String(" ")))
+                            + Qt::escape(docu.join(QLatin1Char(' ')))
                             + QLatin1String("</p>");
                     stream.writeTextElement(QLatin1String(Constants::DOCUMENTATION_XMLDOC), text);
                     stream.writeEndElement();
diff --git a/src/plugins/beautifier/configurationeditor.cpp b/src/plugins/beautifier/configurationeditor.cpp
index 8a75397b5a719e3579c81233a38dc9c44a7c2c79..898de0a122c5f49be96c0a4413f15e017719bd8d 100644
--- a/src/plugins/beautifier/configurationeditor.cpp
+++ b/src/plugins/beautifier/configurationeditor.cpp
@@ -66,7 +66,7 @@ void ConfigurationSyntaxHighlighter::setKeywords(const QStringList &keywords)
             pattern << QRegExp::escape(word);
     }
 
-    m_expressionKeyword.setPattern(QLatin1String("(?:\\s|^)(") + pattern.join(QLatin1String("|"))
+    m_expressionKeyword.setPattern(QLatin1String("(?:\\s|^)(") + pattern.join(QLatin1Char('|'))
                                    + QLatin1String(")(?=\\s|\\:|\\=|\\,|$)"));
 }
 
diff --git a/src/plugins/beautifier/uncrustify/uncrustifysettings.cpp b/src/plugins/beautifier/uncrustify/uncrustifysettings.cpp
index 04a87f20c58caa00a7429245d778fc2b1740b20e..c1453519ae3fba804dbc71fc2f8197961132e2c9 100644
--- a/src/plugins/beautifier/uncrustify/uncrustifysettings.cpp
+++ b/src/plugins/beautifier/uncrustify/uncrustifysettings.cpp
@@ -153,7 +153,7 @@ void UncrustifySettings::createDocumentationFile() const
                 const QString text = QLatin1String("<p><span class=\"option\">") + keyword
                         + QLatin1String("</span> <span class=\"param\">") + options
                         + QLatin1String("</span></p><p>")
-                        + Qt::escape(docu.join(QLatin1String(" ")))
+                        + Qt::escape(docu.join(QLatin1Char(' ')))
                         + QLatin1String("</p>");
                 stream.writeStartElement(QLatin1String(Constants::DOCUMENTATION_XMLENTRY));
                 stream.writeTextElement(QLatin1String(Constants::DOCUMENTATION_XMLKEY), keyword);
diff --git a/src/plugins/clangcodemodel/cppcreatemarkers.cpp b/src/plugins/clangcodemodel/cppcreatemarkers.cpp
index fc9e96ebdf5b6d8fbf9da06e88274936e6d92827..b88849f3c5aa6d6268258fc33fa11f0eb139d3dd 100644
--- a/src/plugins/clangcodemodel/cppcreatemarkers.cpp
+++ b/src/plugins/clangcodemodel/cppcreatemarkers.cpp
@@ -95,7 +95,7 @@ static QString commandLine(const QStringList &options, const QString &fileName)
     foreach (const QString &option, allOptions)
         allOptionsQuoted.append(QLatin1Char('\'') + option + QLatin1Char('\''));
     return ::Utils::HostOsInfo::withExecutableSuffix(QLatin1String("clang"))
-        + QLatin1Char(' ') + allOptionsQuoted.join(QLatin1String(" "));
+        + QLatin1Char(' ') + allOptionsQuoted.join(QLatin1Char(' '));
 }
 
 void CreateMarkers::run()
diff --git a/src/plugins/clangcodemodel/pchmanager.cpp b/src/plugins/clangcodemodel/pchmanager.cpp
index 1b384c3ac3b636f5bce135cfe5a6dba312c109a1..276c9be2a2e2342304020923f4d88abf8937e513 100644
--- a/src/plugins/clangcodemodel/pchmanager.cpp
+++ b/src/plugins/clangcodemodel/pchmanager.cpp
@@ -113,7 +113,7 @@ void PchManager::setPCHInfo(const QList<ProjectPart::Ptr> &projectParts,
                                 pchInfo->fileName()), Core::MessageManager::Silent);
         }
         if (!msgs.second.isEmpty())
-            emit pchMessage(msgs.second.join(QLatin1String("\n")), Core::MessageManager::Flash);
+            emit pchMessage(msgs.second.join(QLatin1Char('\n')), Core::MessageManager::Flash);
     }
 }
 
diff --git a/src/plugins/clangcodemodel/test/clangcompletion_test.cpp b/src/plugins/clangcodemodel/test/clangcompletion_test.cpp
index 512b971755de5908b432664f9089731193938121..e5c1c3aec1f70ecc3b12e0cbc61a919f28fe536a 100644
--- a/src/plugins/clangcodemodel/test/clangcompletion_test.cpp
+++ b/src/plugins/clangcodemodel/test/clangcompletion_test.cpp
@@ -302,7 +302,7 @@ void ClangCodeModelPlugin::test_ObjC_hints()
             QVERIFY2(hint == ccr.hint(), hintError.arg(ccr.hint()).toAscii());
         }
         const QString textError(QString::fromLatin1("Text \"%1\" not found in set %2")
-                                .arg(text).arg(texts.join(QLatin1String(","))));
+                                .arg(text).arg(texts.join(QLatin1Char(','))));
         QVERIFY2(hasText, textError.toAscii());
     }
 }
diff --git a/src/plugins/clearcase/versionselector.cpp b/src/plugins/clearcase/versionselector.cpp
index 9437120c5bab0fb169a688edfa77c6e5badd75ea..1904207d6f4e37435284ed2e6f0c3f8ae2522e45 100644
--- a/src/plugins/clearcase/versionselector.cpp
+++ b/src/plugins/clearcase/versionselector.cpp
@@ -98,7 +98,7 @@ bool VersionSelector::readValues()
             break;
         messageLines << line;
     } while (!m_stream->atEnd());
-    m_message = messageLines.join(QLatin1String(" "));
+    m_message = messageLines.join(QLatin1Char(' '));
     return true;
 }
 
diff --git a/src/plugins/coreplugin/dialogs/newdialog.cpp b/src/plugins/coreplugin/dialogs/newdialog.cpp
index 079d074b9fc4153bd95d95237383bc526d4fd00f..ea0703e1a0df58002a83e1d8b0d73cbe88d50311 100644
--- a/src/plugins/coreplugin/dialogs/newdialog.cpp
+++ b/src/plugins/coreplugin/dialogs/newdialog.cpp
@@ -416,7 +416,7 @@ void NewDialog::currentItemChanged(const QModelIndex &index)
         else
             desciption += tr("Supported Platforms")
                     + QLatin1String("</b>: <tt>")
-                    + displayNamesForSupportedPlatforms.join(QLatin1String(" "))
+                    + displayNamesForSupportedPlatforms.join(QLatin1Char(' '))
                     + QLatin1String("</tt>");
 
         m_ui->templateDescription->setHtml(desciption);
diff --git a/src/plugins/coreplugin/dialogs/readonlyfilesdialog.cpp b/src/plugins/coreplugin/dialogs/readonlyfilesdialog.cpp
index 13b491e424ca855491ae2814ecb094a44dd031f0..b92e6a8ac16fab2a8547e85949f98916a215b4ab 100644
--- a/src/plugins/coreplugin/dialogs/readonlyfilesdialog.cpp
+++ b/src/plugins/coreplugin/dialogs/readonlyfilesdialog.cpp
@@ -234,7 +234,7 @@ void ReadOnlyFilesDialog::promptFailWarning(const QStringList &files, ReadOnlyRe
         message = d->failWarning;
         message += QLatin1Char('\n');
         message += tr("See details for a complete list of files.");
-        details = files.join(QLatin1String("\n"));
+        details = files.join(QLatin1Char('\n'));
     }
     QMessageBox msgBox(QMessageBox::Warning, title, message,
                        QMessageBox::Ok, ICore::dialogParent());
diff --git a/src/plugins/coreplugin/documentmanager.cpp b/src/plugins/coreplugin/documentmanager.cpp
index 6913d01f78902a216139214a4e9a436d0d733bad..69acda1dac49a0335db61c5bcf645b6af7f92998 100644
--- a/src/plugins/coreplugin/documentmanager.cpp
+++ b/src/plugins/coreplugin/documentmanager.cpp
@@ -1113,7 +1113,7 @@ void DocumentManager::checkForReload()
     }
     if (!errorStrings.isEmpty())
         QMessageBox::critical(ICore::dialogParent(), tr("File Error"),
-                              errorStrings.join(QLatin1String("\n")));
+                              errorStrings.join(QLatin1Char('\n')));
 
     // handle deleted files
     EditorManager::closeDocuments(documentsToClose, false);
diff --git a/src/plugins/coreplugin/editormanager/editormanager.cpp b/src/plugins/coreplugin/editormanager/editormanager.cpp
index 830c8339f391b040edac2056c19674a3560d8dbe..4c52ceea5a9d4f3e3edfc337a6fa4ce2f3011e0c 100644
--- a/src/plugins/coreplugin/editormanager/editormanager.cpp
+++ b/src/plugins/coreplugin/editormanager/editormanager.cpp
@@ -1531,7 +1531,7 @@ void EditorManagerPrivate::autoSave()
     }
     if (!errors.isEmpty())
         QMessageBox::critical(ICore::mainWindow(), tr("File Error"),
-                              errors.join(QLatin1String("\n")));
+                              errors.join(QLatin1Char('\n')));
 }
 
 void EditorManagerPrivate::handleContextChange(const QList<IContext *> &context)
diff --git a/src/plugins/coreplugin/generalsettings.cpp b/src/plugins/coreplugin/generalsettings.cpp
index 1fd52b41e222dccc10fc733c008f7b38f7b9312f..a915c6ac36cdd82f1f17f3326226704eb806f71b 100644
--- a/src/plugins/coreplugin/generalsettings.cpp
+++ b/src/plugins/coreplugin/generalsettings.cpp
@@ -224,7 +224,7 @@ void GeneralSettings::updatePath()
 {
     Environment env = Environment::systemEnvironment();
     QStringList toAdd = VcsManager::additionalToolsPath();
-    env.appendOrSetPath(toAdd.join(QString(HostOsInfo::pathListSeparator())));
+    env.appendOrSetPath(toAdd.join(HostOsInfo::pathListSeparator()));
     m_page->patchChooser->setEnvironment(env);
 }
 
diff --git a/src/plugins/coreplugin/locator/directoryfilter.cpp b/src/plugins/coreplugin/locator/directoryfilter.cpp
index 20737a7de72727b108242e9dc9d0444ff65e7332..76a128a03f135af8c3d1f7f1968c1c81b43161f5 100644
--- a/src/plugins/coreplugin/locator/directoryfilter.cpp
+++ b/src/plugins/coreplugin/locator/directoryfilter.cpp
@@ -105,7 +105,7 @@ bool DirectoryFilter::openConfigDialog(QWidget *parent, bool &needsRefresh)
     m_ui.nameEdit->selectAll();
     m_ui.directoryList->clear();
     m_ui.directoryList->addItems(m_directories);
-    m_ui.fileTypeEdit->setText(m_filters.join(QString(QLatin1Char(','))));
+    m_ui.fileTypeEdit->setText(m_filters.join(QLatin1Char(',')));
     m_ui.shortcutEdit->setText(shortcutString());
     m_ui.defaultFlag->setChecked(!isIncludedByDefault());
     updateOptionButtons();
diff --git a/src/plugins/coreplugin/mimedatabase.cpp b/src/plugins/coreplugin/mimedatabase.cpp
index 75276d49eb12bcd3d51f7f406cb76ba1bbbf3e59..84187c89a27217e698dd7064532010f87864d168 100644
--- a/src/plugins/coreplugin/mimedatabase.cpp
+++ b/src/plugins/coreplugin/mimedatabase.cpp
@@ -619,7 +619,7 @@ void MimeTypeData::assignSuffixes(const QStringList &patterns)
 void MimeTypeData::debug(QTextStream &str, int indent) const
 {
     const QString indentS = QString(indent, QLatin1Char(' '));
-    const QString comma = QString(1, QLatin1Char(','));
+    const QLatin1Char comma(',');
     str << indentS << "Type: " << type;
     if (!aliases.empty())
         str << " Aliases: " << aliases.join(comma);
@@ -779,7 +779,7 @@ bool MimeType::setPreferredSuffix(const QString &s)
         qWarning("%s: Attempt to set preferred suffix to '%s', which is not in the list of suffixes: %s.",
                  m_d->type.toUtf8().constData(),
                  s.toUtf8().constData(),
-                 m_d->suffixes.join(QLatin1String(",")).toUtf8().constData());
+                 m_d->suffixes.join(QLatin1Char(',')).toUtf8().constData());
         return false;
     }
     m_d->preferredSuffix = s;
@@ -1280,7 +1280,6 @@ public:
     typedef QHash<QString, QString> AliasMap;
     typedef QMultiHash<QString, QString> ParentChildrenMap;
 
-    static const QChar kSemiColon;
     static const QString kModifiedMimeTypesFile;
     static QString kModifiedMimeTypesPath;
 
@@ -1299,7 +1298,6 @@ public:
     QMutex m_mutex;
 };
 
-const QChar MimeDatabasePrivate::kSemiColon(QLatin1Char(';'));
 const QString MimeDatabasePrivate::kModifiedMimeTypesFile(QLatin1String("modifiedmimetypes.xml"));
 QString MimeDatabasePrivate::kModifiedMimeTypesPath;
 
@@ -1691,7 +1689,7 @@ QList<MimeType> MimeDatabasePrivate::readUserModifiedMimeTypes()
                 if (reader.name() == QLatin1String(mimeTypeTagC)) {
                     mimeType.setType(atts.value(mimeTypeAttribute).toString());
                     const QString &patterns = atts.value(patternAttribute).toString();
-                    mimeType.setGlobPatterns(toGlobPatterns(patterns.split(kSemiColon)));
+                    mimeType.setGlobPatterns(toGlobPatterns(patterns.split(QLatin1Char(';'))));
                 } else if (reader.name() == QLatin1String(matchTagC)) {
                     const QString &value = atts.value(matchValueAttribute).toString();
                     const QStringRef type = atts.value(matchTypeAttribute);
@@ -1762,7 +1760,7 @@ void MimeDatabasePrivate::writeUserModifiedMimeTypes(const QList<MimeType> &mime
                 writer.writeStartElement(mimeTypeTag);
                 writer.writeAttribute(mimeTypeAttribute, mimeType.type());
                 writer.writeAttribute(patternAttribute,
-                                      fromGlobPatterns(mimeType.globPatterns()).join(kSemiColon));
+                                      fromGlobPatterns(mimeType.globPatterns()).join(QLatin1Char(';')));
                 const QList<QSharedPointer<IMagicMatcher> > &matchers = mimeType.magicMatchers();
                 foreach (const QSharedPointer<IMagicMatcher> &matcher, matchers) {
                     // Only care about rule-based matchers.
diff --git a/src/plugins/cpptools/cppcodemodelinspectordumper.cpp b/src/plugins/cpptools/cppcodemodelinspectordumper.cpp
index 2600b7f16a92d1f0d3b0bdc7032ea2d49dccbe62..87c46ffe7bd1e5011ab2dff87d5a82ea8a2a73ca 100644
--- a/src/plugins/cpptools/cppcodemodelinspectordumper.cpp
+++ b/src/plugins/cpptools/cppcodemodelinspectordumper.cpp
@@ -153,7 +153,7 @@ QString Utils::toString(const QList<ProjectFile> &projectFiles)
     foreach (const ProjectFile &projectFile, projectFiles)
         filesList << QDir::toNativeSeparators(projectFile.path);
     ::Utils::sort(filesList);
-    return filesList.join(QLatin1String("\n"));
+    return filesList.join(QLatin1Char('\n'));
 }
 
 QString Utils::toString(ProjectFile::Kind kind)
@@ -412,7 +412,7 @@ QString Utils::pathListToString(const QStringList &pathList)
     QStringList result;
     foreach (const QString &path, pathList)
         result << QDir::toNativeSeparators(path);
-    return result.join(QLatin1String("\n"));
+    return result.join(QLatin1Char('\n'));
 }
 
 QString Utils::pathListToString(const ProjectPart::HeaderPaths &pathList)
@@ -424,7 +424,7 @@ QString Utils::pathListToString(const ProjectPart::HeaderPaths &pathList)
                       path.isFrameworkPath() ? QLatin1String("framework") : QLatin1String("include")
                       );
     }
-    return result.join(QLatin1String("\n"));
+    return result.join(QLatin1Char('\n'));
 }
 
 QList<CPlusPlus::Document::Ptr> Utils::snapshotToList(const CPlusPlus::Snapshot &snapshot)
diff --git a/src/plugins/cpptools/cppfilesettingspage.cpp b/src/plugins/cpptools/cppfilesettingspage.cpp
index 5a9affa451b81b8c92a7ea78c2bd452e3de542ca..601f2fceeba25cb93bd2620936756602e9945361 100644
--- a/src/plugins/cpptools/cppfilesettingspage.cpp
+++ b/src/plugins/cpptools/cppfilesettingspage.cpp
@@ -311,13 +311,14 @@ static inline void setComboText(QComboBox *cb, const QString &text, int defaultI
 
 void CppFileSettingsWidget::setSettings(const CppFileSettings &s)
 {
+    const QChar comma = QLatin1Char(',');
     m_ui->lowerCaseFileNamesCheckBox->setChecked(s.lowerCaseFiles);
-    m_ui->headerPrefixesEdit->setText(s.headerPrefixes.join(QLatin1String(",")));
-    m_ui->sourcePrefixesEdit->setText(s.sourcePrefixes.join(QLatin1String(",")));
+    m_ui->headerPrefixesEdit->setText(s.headerPrefixes.join(comma));
+    m_ui->sourcePrefixesEdit->setText(s.sourcePrefixes.join(comma));
     setComboText(m_ui->headerSuffixComboBox, s.headerSuffix);
     setComboText(m_ui->sourceSuffixComboBox, s.sourceSuffix);
-    m_ui->headerSearchPathsEdit->setText(s.headerSearchPaths.join(QLatin1String(",")));
-    m_ui->sourceSearchPathsEdit->setText(s.sourceSearchPaths.join(QLatin1String(",")));
+    m_ui->headerSearchPathsEdit->setText(s.headerSearchPaths.join(comma));
+    m_ui->sourceSearchPathsEdit->setText(s.sourceSearchPaths.join(comma));
     setLicenseTemplatePath(s.licenseTemplatePath);
 }
 
diff --git a/src/plugins/debugger/cdb/cdbengine.cpp b/src/plugins/debugger/cdb/cdbengine.cpp
index 8090d9785cb73c7b8cff724dd6211d925aca1304..b6befa75cd9193551c7a1067afa5858f5e79d453 100644
--- a/src/plugins/debugger/cdb/cdbengine.cpp
+++ b/src/plugins/debugger/cdb/cdbengine.cpp
@@ -686,10 +686,10 @@ bool CdbEngine::launchCDB(const DebuggerStartParameters &sp, QString *errorMessa
 
     const QStringList &symbolPaths = stringListSetting(CdbSymbolPaths);
     if (!symbolPaths.isEmpty())
-        arguments << QLatin1String("-y") << symbolPaths.join(QString(QLatin1Char(';')));
+        arguments << QLatin1String("-y") << symbolPaths.join(QLatin1Char(';'));
     const QStringList &sourcePaths = stringListSetting(CdbSourcePaths);
     if (!sourcePaths.isEmpty())
-        arguments << QLatin1String("-srcpath") << sourcePaths.join(QString(QLatin1Char(';')));
+        arguments << QLatin1String("-srcpath") << sourcePaths.join(QLatin1Char(';'));
 
     // Compile argument string preserving quotes
     QString nativeArguments = stringSetting(CdbAdditionalArguments);
@@ -727,7 +727,7 @@ bool CdbEngine::launchCDB(const DebuggerStartParameters &sp, QString *errorMessa
 
     const QString msg = QString::fromLatin1("Launching %1 %2\nusing %3 of %4.").
             arg(QDir::toNativeSeparators(executable),
-                arguments.join(QString(blank)) + blank + nativeArguments,
+                arguments.join(blank) + blank + nativeArguments,
                 QDir::toNativeSeparators(extensionFi.absoluteFilePath()),
                 extensionFi.lastModified().toString(Qt::SystemLocaleShortDate));
     showMessage(msg, LogMisc);
diff --git a/src/plugins/debugger/debuggerplugin.cpp b/src/plugins/debugger/debuggerplugin.cpp
index 08f28671cdb608e7e0a8e61c901130e22af135d2..77531a3ff52efe65ecd45c3df9f4dcec629576e8 100644
--- a/src/plugins/debugger/debuggerplugin.cpp
+++ b/src/plugins/debugger/debuggerplugin.cpp
@@ -2640,7 +2640,7 @@ static QString formatStartParameters(DebuggerStartParameters &sp)
                 << " Local: " << sp.localMountDir << '\n';
     }
     str << "Sysroot: " << sp.sysRoot << '\n';
-    str << "Debug Source Location: " << sp.debugSourceLocation.join(QLatin1String(":")) << '\n';
+    str << "Debug Source Location: " << sp.debugSourceLocation.join(QLatin1Char(':')) << '\n';
     return rc;
 }
 
diff --git a/src/plugins/debugger/gdb/gdbengine.cpp b/src/plugins/debugger/gdb/gdbengine.cpp
index c24875231afdb1d7e7810ff4a859cec22ff72e55..07ec32a8a9c33afcf8eb78d6de7b5278212a79ef 100644
--- a/src/plugins/debugger/gdb/gdbengine.cpp
+++ b/src/plugins/debugger/gdb/gdbengine.cpp
@@ -4156,7 +4156,7 @@ void GdbEngine::startGdb(const QStringList &args)
     connect(m_gdbProc, SIGNAL(readyReadStandardError()),
         SLOT(readGdbStandardError()));
 
-    showMessage(_("STARTING ") + m_gdb + _(" ") + gdbArgs.join(_(" ")));
+    showMessage(_("STARTING ") + m_gdb + _(" ") + gdbArgs.join(QLatin1Char(' ')));
     m_gdbProc->start(m_gdb, gdbArgs);
 
     if (!m_gdbProc->waitForStarted()) {
diff --git a/src/plugins/debugger/gdb/remotegdbserveradapter.cpp b/src/plugins/debugger/gdb/remotegdbserveradapter.cpp
index 71aeaea7326da46c9d62296661326738c6701dfe..2c3e22eb9958c66a7c9e06cd560a37a3fc3fd5fd 100644
--- a/src/plugins/debugger/gdb/remotegdbserveradapter.cpp
+++ b/src/plugins/debugger/gdb/remotegdbserveradapter.cpp
@@ -176,7 +176,7 @@ void GdbRemoteServerEngine::setupInferior()
 //    if (!remoteArch.isEmpty())
 //        postCommand("set architecture " + remoteArch);
     const QString solibSearchPath
-            = sp.solibSearchPath.join(QString(Utils::HostOsInfo::pathListSeparator()));
+            = sp.solibSearchPath.join(Utils::HostOsInfo::pathListSeparator());
     if (!solibSearchPath.isEmpty())
         postCommand("set solib-search-path " + solibSearchPath.toLocal8Bit());
 
diff --git a/src/plugins/debugger/lldb/lldbengine.cpp b/src/plugins/debugger/lldb/lldbengine.cpp
index ac4c09ef461ac45a6e849f3b6150381581b6c410..512d5369d480c774e3d67b03296cc06ff837f963 100644
--- a/src/plugins/debugger/lldb/lldbengine.cpp
+++ b/src/plugins/debugger/lldb/lldbengine.cpp
@@ -254,7 +254,7 @@ void LldbEngine::startLldb()
     args.append(_("-i"));
     args.append(Core::ICore::resourcePath() + _("/debugger/lldbbridge.py"));
     args.append(m_lldbCmd);
-    showMessage(_("STARTING LLDB ") + args.join(QLatin1String(" ")));
+    showMessage(_("STARTING LLDB ") + args.join(QLatin1Char(' ')));
     m_lldbProc.setEnvironment(startParameters().environment.toStringList());
     if (!startParameters().workingDirectory.isEmpty())
         m_lldbProc.setWorkingDirectory(startParameters().workingDirectory);
diff --git a/src/plugins/debugger/sourceutils.cpp b/src/plugins/debugger/sourceutils.cpp
index 975ac007a670295b0053c7486e28ab415b986fd8..6b5308419176fe231ae607c9fff121da8b0cb077 100644
--- a/src/plugins/debugger/sourceutils.cpp
+++ b/src/plugins/debugger/sourceutils.cpp
@@ -245,7 +245,7 @@ bool getUninitializedVariables(const CPlusPlus::Snapshot &snapshot,
         QTextStream str(&msg);
         str << "getUninitializedVariables() " << function << ' ' << file << ':' << line
                 << " returns (int) " << rc << " '"
-                << uninitializedVariables->join(QString(QLatin1Char(','))) << '\'';
+                << uninitializedVariables->join(QLatin1Char(',')) << '\'';
         if (rc)
             str << " of " << snapshot.size() << " documents";
         qDebug() << msg;
diff --git a/src/plugins/genericprojectmanager/genericprojectwizard.cpp b/src/plugins/genericprojectmanager/genericprojectwizard.cpp
index 1b58948d7c9bd98defef08c52a7110b8f3283803..81c4a130f7bcd2ff7f3fc17a3b1cf84552034b0c 100644
--- a/src/plugins/genericprojectmanager/genericprojectwizard.cpp
+++ b/src/plugins/genericprojectmanager/genericprojectwizard.cpp
@@ -183,10 +183,10 @@ Core::GeneratedFiles GenericProjectWizard::generateFiles(const QWizard *w,
         sources[i] = dir.relativeFilePath(sources[i]);
 
     Core::GeneratedFile generatedFilesFile(filesFileName);
-    generatedFilesFile.setContents(sources.join(QLatin1String("\n")));
+    generatedFilesFile.setContents(sources.join(QLatin1Char('\n')));
 
     Core::GeneratedFile generatedIncludesFile(includesFileName);
-    generatedIncludesFile.setContents(includePaths.join(QLatin1String("\n")));
+    generatedIncludesFile.setContents(includePaths.join(QLatin1Char('\n')));
 
     Core::GeneratedFile generatedConfigFile(configFileName);
     generatedConfigFile.setContents(QLatin1String(ConfigFileTemplate));
diff --git a/src/plugins/git/branchmodel.cpp b/src/plugins/git/branchmodel.cpp
index f499165872fba95452796718a8e8cac9300b2628..bbdc07cc256fbbe0097c37984f425f4a6bc0bd16 100644
--- a/src/plugins/git/branchmodel.cpp
+++ b/src/plugins/git/branchmodel.cpp
@@ -171,7 +171,7 @@ public:
             }
             return names;
         }
-        return QStringList(fullName().join(QString(QLatin1Char('/'))));
+        return QStringList(fullName().join(QLatin1Char('/')));
     }
 
     int rowOf(BranchNode *node)
@@ -438,7 +438,7 @@ QString BranchModel::fullName(const QModelIndex &idx, bool includePrefix) const
     if (!node || !node->isLeaf())
         return QString();
     QStringList path = node->fullName(includePrefix);
-    return path.join(QString(QLatin1Char('/')));
+    return path.join(QLatin1Char('/'));
 }
 
 QStringList BranchModel::localBranchNames() const
diff --git a/src/plugins/git/gerrit/gerritparameters.cpp b/src/plugins/git/gerrit/gerritparameters.cpp
index d4b2eaee4f34a58928c5f6b07cabfa0d1250b6f1..d871fd0da2e3d6d1f3f6a90d24982e5597d49d64 100644
--- a/src/plugins/git/gerrit/gerritparameters.cpp
+++ b/src/plugins/git/gerrit/gerritparameters.cpp
@@ -132,7 +132,7 @@ void GerritParameters::toSettings(QSettings *s) const
 void GerritParameters::saveQueries(QSettings *s) const
 {
     s->beginGroup(QLatin1String(settingsGroupC));
-    s->setValue(QLatin1String(savedQueriesKeyC), savedQueries.join(QLatin1String(",")));
+    s->setValue(QLatin1String(savedQueriesKeyC), savedQueries.join(QLatin1Char(',')));
     s->endGroup();
 }
 
diff --git a/src/plugins/git/gerrit/gerritplugin.cpp b/src/plugins/git/gerrit/gerritplugin.cpp
index ee1ba7bf4c3516ae91960407e77df62f7db1a595..0eaf572edddf28e58fc01aed265801ea172ea205 100644
--- a/src/plugins/git/gerrit/gerritplugin.cpp
+++ b/src/plugins/git/gerrit/gerritplugin.cpp
@@ -344,7 +344,7 @@ void GerritPlugin::push(const QString &topLevel)
         options << QLatin1String("r=") + reviewer;
 
     if (!options.isEmpty())
-        target += QLatin1Char('%') + options.join(QLatin1String(","));
+        target += QLatin1Char('%') + options.join(QLatin1Char(','));
 
     args << target;
 
diff --git a/src/plugins/git/gitclient.cpp b/src/plugins/git/gitclient.cpp
index 714c792927babe6cde5e404acd07186057b1a708..c54e2464be77b6007c690acaf478dec24f7a9bfa 100644
--- a/src/plugins/git/gitclient.cpp
+++ b/src/plugins/git/gitclient.cpp
@@ -727,7 +727,7 @@ static inline void msgCannotRun(const QStringList &args, const QString &workingD
                                 const QByteArray &error, QString *errorMessage)
 {
     const QString message = GitClient::tr("Cannot run \"%1 %2\" in \"%2\": %3")
-            .arg(QLatin1String("git ") + args.join(QLatin1String(" ")),
+            .arg(QLatin1String("git ") + args.join(QLatin1Char(' ')),
                  QDir::toNativeSeparators(workingDirectory),
                  commandOutputFromLocal8Bit(error));
 
@@ -3220,7 +3220,7 @@ void GitClient::handleMergeConflicts(const QString &workingDir, const QString &c
     if (!commit.isEmpty())
         message = tr("Conflicts detected with commit %1.").arg(commit);
     else if (!files.isEmpty())
-        message = tr("Conflicts detected with files:\n%1").arg(files.join(QLatin1String("\n")));
+        message = tr("Conflicts detected with files:\n%1").arg(files.join(QLatin1Char('\n')));
     else
         message = tr("Conflicts detected.");
     QMessageBox mergeOrAbort(QMessageBox::Question, tr("Conflicts Detected"), message,
diff --git a/src/plugins/git/stashdialog.cpp b/src/plugins/git/stashdialog.cpp
index b3c89b64e0bc6b4e4d54b681e678c72b180d1718..a10696f6f1aee2b725ce544d9c061fa70cc4bbe8 100644
--- a/src/plugins/git/stashdialog.cpp
+++ b/src/plugins/git/stashdialog.cpp
@@ -208,7 +208,7 @@ void StashDialog::deleteSelection()
             errors.push_back(errorMessage);
     refresh(m_repository, true);
     if (!errors.isEmpty())
-        warning(title, errors.join(QString(QLatin1Char('\n'))));
+        warning(title, errors.join(QLatin1Char('\n')));
 }
 
 void StashDialog::showCurrent()
diff --git a/src/plugins/help/remotehelpfilter.cpp b/src/plugins/help/remotehelpfilter.cpp
index 34cc9dbe439eace3f23cfce3abd22f6367a6d966..ff27a4cc3e0dc4c081cc96d15d794904bc9a1764 100644
--- a/src/plugins/help/remotehelpfilter.cpp
+++ b/src/plugins/help/remotehelpfilter.cpp
@@ -126,7 +126,7 @@ QByteArray RemoteHelpFilter::saveState() const
 {
     QByteArray value;
     QDataStream out(&value, QIODevice::WriteOnly);
-    out << m_remoteUrls.join(QLatin1String("^"));
+    out << m_remoteUrls.join(QLatin1Char('^'));
     out << shortcutString();
     out << isIncludedByDefault();
     return value;
diff --git a/src/plugins/ios/iostoolhandler.cpp b/src/plugins/ios/iostoolhandler.cpp
index 2ceff2685c5bfadc0b211f87aee4118700f3c13f..c17679fb23a52567579364685e947c31a4eadbbb 100644
--- a/src/plugins/ios/iostoolhandler.cpp
+++ b/src/plugins/ios/iostoolhandler.cpp
@@ -221,7 +221,7 @@ IosToolHandlerPrivate::IosToolHandlerPrivate(IosDeviceType::Enum devType,
         frameworkPaths << xcPath;
     frameworkPaths << QLatin1String("/System/Library/Frameworks")
                    << QLatin1String("/System/Library/PrivateFrameworks");
-    env.insert(QLatin1String("DYLD_FALLBACK_FRAMEWORK_PATH"), frameworkPaths.join(QLatin1String(":")));
+    env.insert(QLatin1String("DYLD_FALLBACK_FRAMEWORK_PATH"), frameworkPaths.join(QLatin1Char(':')));
     qCDebug(toolHandlerLog) << "IosToolHandler runEnv:" << env.toStringList();
     process.setProcessEnvironment(env);
     QObject::connect(&process, SIGNAL(readyReadStandardOutput()), q, SLOT(subprocessHasData()));
diff --git a/src/plugins/perforce/perforcesubmiteditor.cpp b/src/plugins/perforce/perforcesubmiteditor.cpp
index eb1b3d2f2f09f2acd94154541a87fa0d424a05f0..0063209d49ea6db9caf9a898bbc819155f57bd11 100644
--- a/src/plugins/perforce/perforcesubmiteditor.cpp
+++ b/src/plugins/perforce/perforcesubmiteditor.cpp
@@ -125,7 +125,7 @@ void PerforceSubmitEditor::updateFields()
                     m_entries.value(QLatin1String("Client")).trimmed(),
                     m_entries.value(QLatin1String("User")).trimmed());
 
-    const QString newLine = QString(QLatin1Char('\n'));
+    const QChar newLine = QLatin1Char('\n');
     QStringList lines = m_entries.value(QLatin1String("Description")).split(newLine);
     lines.removeFirst(); // that is the line break after 'Description:'
     lines.removeLast(); // that is the empty line at the end
@@ -150,8 +150,8 @@ void PerforceSubmitEditor::updateFields()
 
 void PerforceSubmitEditor::updateEntries()
 {
-    const QString newLine = QString(QLatin1Char('\n'));
-    const QString tab = QString(QLatin1Char('\t'));
+    const QChar newLine = QLatin1Char('\n');
+    const QChar tab = QLatin1Char('\t');
 
     QStringList lines = submitEditorWidget()->descriptionText().split(newLine);
 
diff --git a/src/plugins/projectexplorer/abi.cpp b/src/plugins/projectexplorer/abi.cpp
index f8fb18ed76b227e9e3b55eb75986cdd59a062302..bd9aab74b0b6fb321000265179893d05c0722834 100644
--- a/src/plugins/projectexplorer/abi.cpp
+++ b/src/plugins/projectexplorer/abi.cpp
@@ -527,7 +527,7 @@ QString Abi::toString() const
     dn << toString(m_binaryFormat);
     dn << toString(m_wordWidth);
 
-    return dn.join(QLatin1String("-"));
+    return dn.join(QLatin1Char('-'));
 }
 
 bool Abi::operator != (const Abi &other) const
diff --git a/src/plugins/projectexplorer/allprojectsfind.cpp b/src/plugins/projectexplorer/allprojectsfind.cpp
index 7762783303951d5e5b58420558e15eba422c1bf0..b54e54782cf860aace6df325a3526d40c6be05ab 100644
--- a/src/plugins/projectexplorer/allprojectsfind.cpp
+++ b/src/plugins/projectexplorer/allprojectsfind.cpp
@@ -123,7 +123,7 @@ QString AllProjectsFind::label() const
 QString AllProjectsFind::toolTip() const
 {
     // %2 is filled by BaseFileFind::runNewSearch
-    return tr("Filter: %1\n%2").arg(fileNameFilters().join(QLatin1String(",")));
+    return tr("Filter: %1\n%2").arg(fileNameFilters().join(QLatin1Char(',')));
 }
 
 void AllProjectsFind::handleFileListChanged()
diff --git a/src/plugins/projectexplorer/customtoolchain.cpp b/src/plugins/projectexplorer/customtoolchain.cpp
index 7384bf7175053dc670d224699c77b14d4553ca67..265b465539e85e232721f154d69c336081a439f9 100644
--- a/src/plugins/projectexplorer/customtoolchain.cpp
+++ b/src/plugins/projectexplorer/customtoolchain.cpp
@@ -585,9 +585,9 @@ void CustomToolChainConfigWidget::setFromToolchain()
     m_compilerCommand->setFileName(tc->compilerCommand());
     m_makeCommand->setFileName(FileName::fromString(tc->makeCommand(Utils::Environment())));
     m_abiWidget->setAbis(QList<Abi>(), tc->targetAbi());
-    m_predefinedMacros->setPlainText(tc->rawPredefinedMacros().join(QLatin1String("\n")));
-    m_headerPaths->setPlainText(tc->headerPathsList().join(QLatin1String("\n")));
-    m_cxx11Flags->setText(tc->cxx11Flags().join(QLatin1String(",")));
+    m_predefinedMacros->setPlainText(tc->rawPredefinedMacros().join(QLatin1Char('\n')));
+    m_headerPaths->setPlainText(tc->headerPathsList().join(QLatin1Char('\n')));
+    m_cxx11Flags->setText(tc->cxx11Flags().join(QLatin1Char(',')));
     m_mkspecs->setText(tc->mkspecs());
     m_errorParserComboBox->setCurrentIndex(tc->outputParserType());
     m_customParserSettings = tc->customParserSettings();
diff --git a/src/plugins/projectexplorer/customwizard/customwizardscriptgenerator.cpp b/src/plugins/projectexplorer/customwizard/customwizardscriptgenerator.cpp
index ffc34798d3534301e08cdeec1962f7d3e2ced1d9..933e6db7368865d4e6f67836e4ded610c1f2fbaa 100644
--- a/src/plugins/projectexplorer/customwizard/customwizardscriptgenerator.cpp
+++ b/src/plugins/projectexplorer/customwizard/customwizardscriptgenerator.cpp
@@ -114,7 +114,7 @@ static bool
     if (CustomWizard::verbose())
         qDebug("In %s, running:\n%s\n%s\n", qPrintable(workingDirectory),
                qPrintable(binary),
-               qPrintable(arguments.join(QString(QLatin1Char(' ')))));
+               qPrintable(arguments.join(QLatin1Char(' '))));
     process.start(binary, arguments);
     if (!process.waitForStarted()) {
         *errorMessage = QString::fromLatin1("Unable to start generator script %1: %2").
diff --git a/src/plugins/projectexplorer/devicesupport/sshdeviceprocess.cpp b/src/plugins/projectexplorer/devicesupport/sshdeviceprocess.cpp
index a6585d0a7a6d175088b100be6bb74a65026e99bf..57fb1f6c0d50dbe11c0e7fad1cec737ddd3c41f2 100644
--- a/src/plugins/projectexplorer/devicesupport/sshdeviceprocess.cpp
+++ b/src/plugins/projectexplorer/devicesupport/sshdeviceprocess.cpp
@@ -300,7 +300,7 @@ QString SshDeviceProcess::fullCommandLine() const
 {
     QString cmdLine = executable();
     if (!arguments().isEmpty())
-        cmdLine.append(QLatin1Char(' ')).append(arguments().join(QLatin1String(" ")));
+        cmdLine.append(QLatin1Char(' ')).append(arguments().join(QLatin1Char(' ')));
     return cmdLine;
 }
 
diff --git a/src/plugins/projectexplorer/environmentitemswidget.cpp b/src/plugins/projectexplorer/environmentitemswidget.cpp
index 19f6bd0e5481c605d25691bfbe44e7489409335a..e5f058ece738ae2a309d4f4461d6ad5c124229ff 100644
--- a/src/plugins/projectexplorer/environmentitemswidget.cpp
+++ b/src/plugins/projectexplorer/environmentitemswidget.cpp
@@ -85,7 +85,7 @@ void EnvironmentItemsWidget::setEnvironmentItems(const QList<Utils::EnvironmentI
     QList<Utils::EnvironmentItem> sortedItems = items;
     Utils::EnvironmentItem::sort(&sortedItems);
     QStringList list = Utils::EnvironmentItem::toStringList(sortedItems);
-    d->m_editor->document()->setPlainText(list.join(QLatin1String("\n")));
+    d->m_editor->document()->setPlainText(list.join(QLatin1Char('\n')));
 }
 
 QList<Utils::EnvironmentItem> EnvironmentItemsWidget::environmentItems() const
diff --git a/src/plugins/projectexplorer/gcctoolchain.cpp b/src/plugins/projectexplorer/gcctoolchain.cpp
index 25f319392a52efae934a249dda9bf917e6223455..c130107280d70effb21a65893e3ebb11da1efd70 100644
--- a/src/plugins/projectexplorer/gcctoolchain.cpp
+++ b/src/plugins/projectexplorer/gcctoolchain.cpp
@@ -100,7 +100,7 @@ static QByteArray runGcc(const FileName &gcc, const QStringList &arguments, cons
     if (cpp.exitCode() != 0) {
         qWarning().nospace()
             << Q_FUNC_INFO << ": " << gcc.toUserOutput() << ' '
-            << arguments.join(QLatin1String(" ")) << " returned exit code "
+            << arguments.join(QLatin1Char(' ')) << " returned exit code "
             << cpp.exitCode() << ": " << stdErr;
         return QByteArray();
     }
diff --git a/src/plugins/projectexplorer/projectexplorer.cpp b/src/plugins/projectexplorer/projectexplorer.cpp
index 4d643e219f2abc1d61a198e9b905f6f62d8b79c2..ae5fd59a98d06f5c128ec469e7dcb33d6859e671 100644
--- a/src/plugins/projectexplorer/projectexplorer.cpp
+++ b/src/plugins/projectexplorer/projectexplorer.cpp
@@ -3022,7 +3022,7 @@ void ProjectExplorerPlugin::addExistingFiles(FolderNode *folderNode, const QStri
     if (!notAdded.isEmpty()) {
         QString message = tr("Could not add following files to project %1:").arg(folderNode->projectNode()->displayName());
         message += QLatin1Char('\n');
-        QString files = notAdded.join(QString(QLatin1Char('\n')));
+        QString files = notAdded.join(QLatin1Char('\n'));
         QMessageBox::warning(ICore::mainWindow(), tr("Adding Files to Project Failed"),
                              message + files);
         foreach (const QString &file, notAdded)
diff --git a/src/plugins/projectexplorer/projectfilewizardextension.cpp b/src/plugins/projectexplorer/projectfilewizardextension.cpp
index f95f1c9b37892aab66d2311534ae46252920b141..d4e41c2a2ae73847af0cc30f2c05072534242233 100644
--- a/src/plugins/projectexplorer/projectfilewizardextension.cpp
+++ b/src/plugins/projectexplorer/projectfilewizardextension.cpp
@@ -206,7 +206,7 @@ bool ProjectFileWizardExtension::processProject(
         QStringList filePaths = Utils::transform(files, &GeneratedFile::path);
         if (!folder->addFiles(filePaths)) {
             *errorMessage = tr("Failed to add one or more files to project\n\"%1\" (%2).").
-                    arg(folder->path(), filePaths.join(QString(QLatin1Char(','))));
+                    arg(folder->path(), filePaths.join(QLatin1Char(',')));
             return false;
         }
     }
diff --git a/src/plugins/projectexplorer/targetsettingspanel.cpp b/src/plugins/projectexplorer/targetsettingspanel.cpp
index 5ee453a96be08c423eed25538d99e14cb4daac5b..aeee73c73e59b4406daa3e7f2061723f5c61f6e4 100644
--- a/src/plugins/projectexplorer/targetsettingspanel.cpp
+++ b/src/plugins/projectexplorer/targetsettingspanel.cpp
@@ -442,21 +442,21 @@ Target *TargetSettingsPanelWidget::cloneTarget(Target *sourceTarget, Kit *k)
         if (!buildconfigurationError.isEmpty())
             error += tr("Build configurations:")
                     + QLatin1Char('\n')
-                    + buildconfigurationError.join(QLatin1String("\n"));
+                    + buildconfigurationError.join(QLatin1Char('\n'));
 
         if (!deployconfigurationError.isEmpty()) {
             if (!error.isEmpty())
                 error.append(QLatin1Char('\n'));
             error += tr("Deploy configurations:")
                     + QLatin1Char('\n')
-                    + deployconfigurationError.join(QLatin1String("\n"));
+                    + deployconfigurationError.join(QLatin1Char('\n'));
         }
 
         if (!runconfigurationError.isEmpty()) {
             if (!error.isEmpty())
                 error.append(QLatin1Char('\n'));
             error += tr("Run configurations") + QLatin1Char(' ')
-                    + runconfigurationError.join(QLatin1String("\n"));
+                    + runconfigurationError.join(QLatin1Char('\n'));
         }
 
         QMessageBox msgBox(Core::ICore::mainWindow());
diff --git a/src/plugins/qmakeprojectmanager/customwidgetwizard/plugingenerator.cpp b/src/plugins/qmakeprojectmanager/customwidgetwizard/plugingenerator.cpp
index c2524a223b7a5a52fe94712c22bff36fbf6d0fda..24a15efa41ffef532a4ede60089fa1c6798aaef4 100644
--- a/src/plugins/qmakeprojectmanager/customwidgetwizard/plugingenerator.cpp
+++ b/src/plugins/qmakeprojectmanager/customwidgetwizard/plugingenerator.cpp
@@ -295,8 +295,8 @@ QList<Core::GeneratedFile>  PluginGenerator::generatePlugin(const GenerationPara
     sm.insert(QLatin1String("PLUGIN_HEADERS"), pluginHeaders);
     sm.insert(QLatin1String("PLUGIN_SOURCES"), pluginSources);
     sm.insert(QLatin1String("PLUGIN_RESOURCES"), options.resourceFile);
-    sm.insert(QLatin1String("WIDGET_LIBS"), QStringList(widgetLibraries.toList()).join(QString(blank)));
-    sm.insert(QLatin1String("INCLUSIONS"), QStringList(widgetProjects.toList()).join(QLatin1String("\n")));
+    sm.insert(QLatin1String("WIDGET_LIBS"), QStringList(widgetLibraries.toList()).join(blank));
+    sm.insert(QLatin1String("INCLUSIONS"), QStringList(widgetProjects.toList()).join(QLatin1Char('\n')));
     const QString proFileContents = processTemplate(p.templatePath + QLatin1String("/tpl_plugin.pro"), sm, errorMessage);
     if (proFileContents.isEmpty())
         return QList<Core::GeneratedFile>();
diff --git a/src/plugins/qmakeprojectmanager/externaleditors.cpp b/src/plugins/qmakeprojectmanager/externaleditors.cpp
index 2b5c97f0797d5eb276563afd217ad9362e9cb09d..d40fc925a3f4cc69d7bdbd0cf25784c2811ee791 100644
--- a/src/plugins/qmakeprojectmanager/externaleditors.cpp
+++ b/src/plugins/qmakeprojectmanager/externaleditors.cpp
@@ -55,7 +55,7 @@ namespace Internal {
 static inline QString msgStartFailed(const QString &binary, QStringList arguments)
 {
     arguments.push_front(binary);
-    return ExternalQtEditor::tr("Unable to start \"%1\"").arg(arguments.join(QString(QLatin1Char(' '))));
+    return ExternalQtEditor::tr("Unable to start \"%1\"").arg(arguments.join(QLatin1Char(' ')));
 }
 
 static inline QString msgAppNotFound(const QString &id)
diff --git a/src/plugins/qmakeprojectmanager/qmakenodes.cpp b/src/plugins/qmakeprojectmanager/qmakenodes.cpp
index 43da2227b88fa7e2745f6d04c17d9bd90930e965..e7bbf29f68b656a5f95c63969cf1499b00f9725e 100644
--- a/src/plugins/qmakeprojectmanager/qmakenodes.cpp
+++ b/src/plugins/qmakeprojectmanager/qmakenodes.cpp
@@ -1234,7 +1234,7 @@ void QmakePriFileNode::save(const QStringList &lines)
 {
     Core::DocumentManager::expectFileChange(m_projectFilePath);
     Utils::FileSaver saver(m_projectFilePath, QIODevice::Text);
-    saver.write(lines.join(QLatin1String("\n")).toLocal8Bit());
+    saver.write(lines.join(QLatin1Char('\n')).toLocal8Bit());
     saver.finalize(Core::ICore::mainWindow());
 
     m_project->qmakeProjectManager()->notifyChanged(m_projectFilePath);
@@ -1253,7 +1253,7 @@ void QmakePriFileNode::save(const QStringList &lines)
     }
     if (!errorStrings.isEmpty())
         QMessageBox::warning(Core::ICore::mainWindow(), tr("File Error"),
-                             errorStrings.join(QLatin1String("\n")));
+                             errorStrings.join(QLatin1Char('\n')));
 }
 
 QStringList QmakePriFileNode::varNames(ProjectExplorer::FileType type, QtSupport::ProFileReader *readerExact)
diff --git a/src/plugins/qmakeprojectmanager/wizards/abstractmobileapp.cpp b/src/plugins/qmakeprojectmanager/wizards/abstractmobileapp.cpp
index 1613d166e87982d4d738f46516d3ad1f8172ce45..7179fc630763a600cebda18af6356213178745ce 100644
--- a/src/plugins/qmakeprojectmanager/wizards/abstractmobileapp.cpp
+++ b/src/plugins/qmakeprojectmanager/wizards/abstractmobileapp.cpp
@@ -181,7 +181,7 @@ QByteArray AbstractMobileApp::generateProFile(QString *errorMessage) const
                 folders.append(folderName);
             }
             if (foldersCount > 0)
-                out << "DEPLOYMENTFOLDERS = " << folders.join(QLatin1String(" ")) << endl;
+                out << "DEPLOYMENTFOLDERS = " << folders.join(QLatin1Char(' ')) << endl;
         } else if (line.contains(QLatin1String("# REMOVE_NEXT_LINE"))) {
             in.readLine(); // eats the following line
         } else {
diff --git a/src/plugins/qmldesigner/components/propertyeditor/propertyeditorqmlbackend.cpp b/src/plugins/qmldesigner/components/propertyeditor/propertyeditorqmlbackend.cpp
index 1207514ecf9951cc17993e37598cd85404302d20..52c6dd657b58b91f8a989f6445b31d51b016d193 100644
--- a/src/plugins/qmldesigner/components/propertyeditor/propertyeditorqmlbackend.cpp
+++ b/src/plugins/qmldesigner/components/propertyeditor/propertyeditorqmlbackend.cpp
@@ -337,7 +337,7 @@ QString PropertyEditorQmlBackend::templateGeneration(NodeMetaInfo type,
 
     QStringList imports = variantToStringList(templateConfiguration()->property(QStringLiteral("imports")));
 
-    QString qmlTemplate = imports.join(QStringLiteral("\n")) + QLatin1Char('\n');
+    QString qmlTemplate = imports.join(QLatin1Char('\n')) + QLatin1Char('\n');
     qmlTemplate += QStringLiteral("Section {\n");
     qmlTemplate += QStringLiteral("caption: \"%1\"\n").arg(QString::fromUtf8(objectNode.modelNode().simplifiedTypeName()));
     qmlTemplate += QStringLiteral("SectionLayout {\n");
diff --git a/src/plugins/qmldesigner/designercore/metainfo/metainfo.cpp b/src/plugins/qmldesigner/designercore/metainfo/metainfo.cpp
index 22fdb7a40d053c6435041d1b479399ef1ae662fd..ccbc7ac2f0851b18da7bc69239b36f6e5ba95ff5 100644
--- a/src/plugins/qmldesigner/designercore/metainfo/metainfo.cpp
+++ b/src/plugins/qmldesigner/designercore/metainfo/metainfo.cpp
@@ -98,7 +98,7 @@ void MetaInfoPrivate::parseItemLibraryDescriptions()
             reader.readMetaInfoFile(plugin->metaInfo());
         } catch (InvalidMetaInfoException &e) {
             qWarning() << e.description();
-            const QString errorMessage = plugin->metaInfo() + QLatin1Char('\n') + QLatin1Char('\n') + reader.errors().join(QStringLiteral("\n"));
+            const QString errorMessage = plugin->metaInfo() + QLatin1Char('\n') + QLatin1Char('\n') + reader.errors().join(QLatin1Char('\n'));
             QmlDesignerWarning::show(QCoreApplication::translate("QmlDesigner::Internal::MetaInfoPrivate", "Invalid meta info"),
                                   errorMessage);
         }
diff --git a/src/plugins/qmldesigner/designercore/metainfo/nodemetainfo.cpp b/src/plugins/qmldesigner/designercore/metainfo/nodemetainfo.cpp
index aa5d5e387d4ce33b03ddfbd123e08878d22e9ead..c92cc6d980b4e5bb351a80e2cbf1579f737078b3 100644
--- a/src/plugins/qmldesigner/designercore/metainfo/nodemetainfo.cpp
+++ b/src/plugins/qmldesigner/designercore/metainfo/nodemetainfo.cpp
@@ -968,7 +968,7 @@ static QString getPackage(const QString &name)
         return QString();
     nameComponents.removeLast();
 
-    return nameComponents.join(QStringLiteral("."));
+    return nameComponents.join(QLatin1Char('.'));
 }
 
 bool NodeMetaInfoPrivate::cleverCheckType(const QString &otherType) const
@@ -1132,7 +1132,7 @@ QString NodeMetaInfoPrivate::lookupName() const
     QStringList packageClassName = className.split(QLatin1Char('.'));
     if (packageClassName.size() > 1) {
         className = packageClassName.takeLast();
-        packageName = packageClassName.join(QStringLiteral("."));
+        packageName = packageClassName.join(QLatin1Char('.'));
     }
 
     return CppQmlTypes::qualifiedName(
diff --git a/src/plugins/qmldesigner/designercore/metainfo/subcomponentmanager.cpp b/src/plugins/qmldesigner/designercore/metainfo/subcomponentmanager.cpp
index 74b8234653367896cd2601fba048ee0cd243980f..4622706012e9dc1a76cc58bc2598b3947b3f9f21 100644
--- a/src/plugins/qmldesigner/designercore/metainfo/subcomponentmanager.cpp
+++ b/src/plugins/qmldesigner/designercore/metainfo/subcomponentmanager.cpp
@@ -237,7 +237,7 @@ void SubComponentManager::parseDirectory(const QString &canonicalDirPath, bool a
                     reader.readMetaInfoFile(metaInfoFile.absoluteFilePath(), true);
                 } catch (InvalidMetaInfoException &e) {
                     qWarning() << e.description();
-                    const QString errorMessage = metaInfoFile.absoluteFilePath() + QLatin1Char('\n') + QLatin1Char('\n') + reader.errors().join(QStringLiteral("\n"));
+                    const QString errorMessage = metaInfoFile.absoluteFilePath() + QLatin1Char('\n') + QLatin1Char('\n') + reader.errors().join(QLatin1Char('\n'));
                     QmlDesignerWarning::show(QCoreApplication::translate("SubComponentManager::parseDirectory", "Invalid meta info"),
                                           errorMessage);
                 }
diff --git a/src/plugins/qmljseditor/qmljshoverhandler.cpp b/src/plugins/qmljseditor/qmljshoverhandler.cpp
index 504377681a22126b9a0a01aff39dc421c9a7ac89..602007a24b969b0b28c1cb6995b2a3308999d9ab 100644
--- a/src/plugins/qmljseditor/qmljshoverhandler.cpp
+++ b/src/plugins/qmljseditor/qmljshoverhandler.cpp
@@ -158,13 +158,13 @@ bool HoverHandler::setQmlTypeHelp(const ScopeChain &scopeChain, const Document::
         QStringList helpIdPieces(qName);
         helpIdPieces.prepend(moduleName);
         helpIdPieces.prepend(QLatin1String("QML"));
-        helpId = helpIdPieces.join(QLatin1String("."));
+        helpId = helpIdPieces.join(QLatin1Char('.'));
         if (!HelpManager::linksForIdentifier(helpId).isEmpty())
             break;
         if (helpIdPieces.size() > 3) {
             QString lm = helpIdPieces.value(2);
             helpIdPieces.removeAt(2);
-            helpId = helpIdPieces.join(QLatin1String("."));
+            helpId = helpIdPieces.join(QLatin1Char('.'));
             if (!HelpManager::linksForIdentifier(helpId).isEmpty())
                 break;
             helpIdPieces.replace(1, lm);
@@ -172,12 +172,12 @@ bool HoverHandler::setQmlTypeHelp(const ScopeChain &scopeChain, const Document::
                 break;
         }
         helpIdPieces.removeAt(1);
-        helpId = helpIdPieces.join(QLatin1String("."));
+        helpId = helpIdPieces.join(QLatin1Char('.'));
         if (!HelpManager::linksForIdentifier(helpId).isEmpty())
             break;
         return false;
     } while (0);
-    setLastHelpItemIdentified(TextEditor::HelpItem(helpId, qName.join(QLatin1String(".")),
+    setLastHelpItemIdentified(TextEditor::HelpItem(helpId, qName.join(QLatin1Char('.')),
                                                    TextEditor::HelpItem::QmlComponent));
     return true;
 }
diff --git a/src/plugins/qnx/bardescriptoreditorgeneralwidget.cpp b/src/plugins/qnx/bardescriptoreditorgeneralwidget.cpp
index d03133c654c6d916696d0610445b7c0e736cf520..f4e1ff9316434d6c43afb56e91bba265b3a4f41d 100644
--- a/src/plugins/qnx/bardescriptoreditorgeneralwidget.cpp
+++ b/src/plugins/qnx/bardescriptoreditorgeneralwidget.cpp
@@ -73,7 +73,7 @@ void BarDescriptorEditorGeneralWidget::updateWidgetValue(BarDescriptorDocument::
             unblockSignalMapping(BarDescriptorDocument::aspectRatio);
         }
     } else if (tag == BarDescriptorDocument::arg) {
-        m_ui->applicationArguments->setText(value.toStringList().join(QLatin1String(" ")));
+        m_ui->applicationArguments->setText(value.toStringList().join(QLatin1Char(' ')));
     } else {
         BarDescriptorEditorAbstractPanelWidget::updateWidgetValue(tag, value);
     }
diff --git a/src/plugins/qnx/blackberryabstractdeploystep.cpp b/src/plugins/qnx/blackberryabstractdeploystep.cpp
index 5765a252edf3749ffe4275190c922ac158d7b9eb..38e2f30577164d2f8ad1760233a766ca33cec1be 100644
--- a/src/plugins/qnx/blackberryabstractdeploystep.cpp
+++ b/src/plugins/qnx/blackberryabstractdeploystep.cpp
@@ -126,7 +126,7 @@ void BlackBerryAbstractDeployStep::addCommand(const QString &command, const QStr
 {
     ProjectExplorer::ProcessParameters param;
     param.setCommand(command);
-    param.setArguments(arguments.join(QLatin1String(" ")));
+    param.setArguments(arguments.join(QLatin1Char(' ')));
     m_params << param;
 }
 
diff --git a/src/plugins/qnx/blackberryapilevelconfiguration.cpp b/src/plugins/qnx/blackberryapilevelconfiguration.cpp
index ca71fa9e0aad75ae9ed0cdd29a2a43c03b070bbb..1879d2057e0160d6d476bddd05cf73f5c3e620d3 100644
--- a/src/plugins/qnx/blackberryapilevelconfiguration.cpp
+++ b/src/plugins/qnx/blackberryapilevelconfiguration.cpp
@@ -291,7 +291,7 @@ bool BlackBerryApiLevelConfiguration::activate()
             return false;
 
         QString errorMessage = tr("The following errors occurred while activating target: %1\n").arg(m_targetName);
-        errorMessage.append(validationErrors().join(QLatin1String("\n")));
+        errorMessage.append(validationErrors().join(QLatin1Char('\n')));
         QMessageBox::warning(Core::ICore::mainWindow(), tr("Cannot Set up BB10 Configuration"),
                              errorMessage, QMessageBox::Ok);
         return false;
diff --git a/src/plugins/qnx/blackberryapplicationrunner.cpp b/src/plugins/qnx/blackberryapplicationrunner.cpp
index 64447725a6911bbe5a6173c7c5648d59b57b9b9c..572c4e46c6839017e547fb80a90a9a6b903d2d2f 100644
--- a/src/plugins/qnx/blackberryapplicationrunner.cpp
+++ b/src/plugins/qnx/blackberryapplicationrunner.cpp
@@ -323,7 +323,7 @@ void BlackBerryApplicationRunner::checkQmlJsDebugArguments()
     QStringList args;
     args << QLatin1String("-listManifest") << QDir::toNativeSeparators(m_barPackage);
     if (debugCheckQmlJSArgs)
-        qDebug() << "get manifest:" << nativePackagerCmd << args.join(QLatin1String(" "));
+        qDebug() << "get manifest:" << nativePackagerCmd << args.join(QLatin1Char(' '));
     m_checkQmlJsDebugArgumentsProcess->start(nativePackagerCmd, args);
 }
 
@@ -354,7 +354,7 @@ void BlackBerryApplicationRunner::checkQmlJsDebugArgumentsManifestLoaded()
                 .arg(m_qmlDebugServerPort)
                 .arg(m_launchFlags.testFlag(QmlDebugLaunchBlocking)? QLatin1String(",block"): QLatin1String(""));
             it.insert(QLatin1String("  ") + qmljsdbgArg);
-            manifestContent = manifestLines.join(QLatin1String("\n"));
+            manifestContent = manifestLines.join(QLatin1Char('\n'));
             break;
         }
     }
@@ -383,7 +383,7 @@ void BlackBerryApplicationRunner::checkQmlJsDebugArgumentsManifestLoaded()
     args << manifestFile->fileName();
     args << QLatin1String("app/META-INF/MANIFEST.MF");
     if (debugCheckQmlJSArgs)
-        qDebug() << "set manifest:" << m_deployCmd << args.join(QLatin1String(" "));
+        qDebug() << "set manifest:" << m_deployCmd << args.join(QLatin1Char(' '));
     m_checkQmlJsDebugArgumentsProcess->start(m_deployCmd, args);
 }
 
@@ -427,7 +427,7 @@ void BlackBerryApplicationRunner::launchApplication()
         m_launchProcess->setEnvironment(m_environment.toStringList());
     }
     if (debugCheckQmlJSArgs)
-        qDebug() << "launch:" << m_deployCmd << args.join(QLatin1String(" "));
+        qDebug() << "launch:" << m_deployCmd << args.join(QLatin1Char(' '));
     m_launchProcess->start(m_deployCmd, args);
     m_runningStateTimer->start();
     m_running = true;
diff --git a/src/plugins/qnx/blackberrydebugtokenreader.cpp b/src/plugins/qnx/blackberrydebugtokenreader.cpp
index 9c811bd2412a75a81f287ac2fb499adeb5518a83..4168e0e50b0ac442c6d10fd393fdbf0e559315c6 100644
--- a/src/plugins/qnx/blackberrydebugtokenreader.cpp
+++ b/src/plugins/qnx/blackberrydebugtokenreader.cpp
@@ -104,7 +104,7 @@ QString BlackBerryDebugTokenReader::pins() const
         pinsHexa << hexa.setNum(pin.toUInt(), 16);
     }
 
-    return pinsHexa.join(QLatin1String(","));
+    return pinsHexa.join(QLatin1Char(','));
 }
 
 bool BlackBerryDebugTokenReader::isSupported()
diff --git a/src/plugins/qnx/blackberrykeyswidget.cpp b/src/plugins/qnx/blackberrykeyswidget.cpp
index 91db7b47c0c497ab4e53a4e982a5d2497a2b7a92..68d6ad4a1fae7bf8634e9725fb4873066bb90861 100644
--- a/src/plugins/qnx/blackberrykeyswidget.cpp
+++ b/src/plugins/qnx/blackberrykeyswidget.cpp
@@ -288,7 +288,7 @@ void BlackBerryKeysWidget::updateDebugToken(const QStringList &pins)
     const QString debugTokenPath = m_dtModel->item(m_ui->debugTokens->currentIndex().row(), 0)->text();
     m_requester->requestDebugToken(debugTokenPath,
                                    cskPassword, BlackBerryConfigurationManager::instance()->defaultKeystorePath(),
-                                   certificatePassword, pins.join(QLatin1String(",")));
+                                   certificatePassword, pins.join(QLatin1Char(',')));
 }
 
 void BlackBerryKeysWidget::requestFinished(int status)
diff --git a/src/plugins/qnx/cascadesimport/projectfileconverter.cpp b/src/plugins/qnx/cascadesimport/projectfileconverter.cpp
index 46eb87c031512dab5ad31217af0942dc62b794df..114b64e9287ec6a21d27cf710318ee34831002b7 100644
--- a/src/plugins/qnx/cascadesimport/projectfileconverter.cpp
+++ b/src/plugins/qnx/cascadesimport/projectfileconverter.cpp
@@ -102,7 +102,7 @@ static QString updateVariable(const QString &varStr, const QString &varsToAdd,
         var.remove(s);
 
     QStringList sl = QStringList::fromSet(var);
-    return sl.join(QLatin1String(" "));
+    return sl.join(QLatin1Char(' '));
 }
 
 bool ProjectFileConverter::convertFile(Core::GeneratedFile &file, QString &errorMessage)
diff --git a/src/plugins/qnx/qnxruncontrolfactory.cpp b/src/plugins/qnx/qnxruncontrolfactory.cpp
index e54d2f9d98124d25ebfb76cb66f4c8eca9d26141..6f76a1c88389213befe1fd72695d136b6ec8b6e4 100644
--- a/src/plugins/qnx/qnxruncontrolfactory.cpp
+++ b/src/plugins/qnx/qnxruncontrolfactory.cpp
@@ -87,7 +87,7 @@ static DebuggerStartParameters createDebuggerStartParameters(const QnxRunConfigu
     params.displayName = runConfig->displayName();
     params.remoteSetupNeeded = true;
     params.closeMode = KillAtClose;
-    params.processArgs = runConfig->arguments().join(QLatin1String(" "));
+    params.processArgs = runConfig->arguments().join(QLatin1Char(' '));
 
     Debugger::DebuggerRunConfigurationAspect *aspect
             = runConfig->extraAspect<Debugger::DebuggerRunConfigurationAspect>();
@@ -129,7 +129,7 @@ static AnalyzerStartParameters createAnalyzerStartParameters(const QnxRunConfigu
         params.startMode = StartLocal;
     params.runMode = mode;
     params.debuggee = runConfig->remoteExecutableFilePath();
-    params.debuggeeArgs = runConfig->arguments().join(QLatin1String(" "));
+    params.debuggeeArgs = runConfig->arguments().join(QLatin1Char(' '));
     params.connParams = DeviceKitInformation::device(runConfig->target()->kit())->sshParameters();
     params.displayName = runConfig->displayName();
     params.sysroot = SysRootKitInformation::sysRoot(runConfig->target()->kit()).toString();
diff --git a/src/plugins/qnx/qnxversionnumber.cpp b/src/plugins/qnx/qnxversionnumber.cpp
index 80a5c011f9dae30d574432a70b3573083de56642..3090ef84c666508afa110c45995b5add5f6bfdac 100644
--- a/src/plugins/qnx/qnxversionnumber.cpp
+++ b/src/plugins/qnx/qnxversionnumber.cpp
@@ -54,7 +54,7 @@ QnxVersionNumber::QnxVersionNumber()
 
 QString QnxVersionNumber::toString() const
 {
-    return m_segments.join(QLatin1String("."));
+    return m_segments.join(QLatin1Char('.'));
 }
 
 bool QnxVersionNumber::operator >(const QnxVersionNumber &b) const
diff --git a/src/plugins/qtsupport/exampleslistmodel.cpp b/src/plugins/qtsupport/exampleslistmodel.cpp
index 7e3f465f1b969a5d39ab47767e61d9695541d3c0..e3b946e6614d919025244d2a48c2ad73d601e005 100644
--- a/src/plugins/qtsupport/exampleslistmodel.cpp
+++ b/src/plugins/qtsupport/exampleslistmodel.cpp
@@ -657,7 +657,7 @@ QVariant ExamplesListModel::data(const QModelIndex &index, int role) const
     switch (role)
     {
     case Qt::DisplayRole: // for search only
-        return QString(prefixForItem(item) + item.name + QLatin1Char(' ') + item.tags.join(QLatin1String(" ")));
+        return QString(prefixForItem(item) + item.name + QLatin1Char(' ') + item.tags.join(QLatin1Char(' ')));
     case Name:
         return item.name;
     case ProjectPath:
diff --git a/src/plugins/qtsupport/qtoptionspage.cpp b/src/plugins/qtsupport/qtoptionspage.cpp
index 6755ec4f34047b3719494656ea35742602f3d584..49c3c89eb0d788b0c54d2c076073a17101653ec5 100644
--- a/src/plugins/qtsupport/qtoptionspage.cpp
+++ b/src/plugins/qtsupport/qtoptionspage.cpp
@@ -376,7 +376,7 @@ QtOptionsPageWidget::ValidityInfo QtOptionsPageWidget::validInformation(const Ba
     if (useable) {
         warnings += version->warningReason();
         if (!warnings.isEmpty()) {
-            info.message = warnings.join(QLatin1String("\n"));
+            info.message = warnings.join(QLatin1Char('\n'));
             info.icon = m_warningVersionIcon;
         }
     }
diff --git a/src/plugins/qtsupport/qtversionmanager.cpp b/src/plugins/qtsupport/qtversionmanager.cpp
index 03d8d719e06eeda0d778858efb83e6f9ea5912ff..8d79fa5a8f1cfe9ab1b8df10917a0ba0ebc83106 100644
--- a/src/plugins/qtsupport/qtversionmanager.cpp
+++ b/src/plugins/qtsupport/qtversionmanager.cpp
@@ -801,7 +801,7 @@ static BaseQtVersion::QmakeBuildConfigs qmakeBuildConfigFromCmdArgs(QList<QMakeA
                     newValues.append(value);
                 }
                 QMakeAssignment newQA = qa;
-                newQA.value = newValues.join(QLatin1String(" "));
+                newQA.value = newValues.join(QLatin1Char(' '));
                 if (!newValues.isEmpty())
                     assignments->append(newQA);
             }
diff --git a/src/plugins/qtsupport/winceqtversionfactory.cpp b/src/plugins/qtsupport/winceqtversionfactory.cpp
index d6711f74004f6640c54dfa79dfba95eb680c2fa2..095b95b07a8476d2d84926847ab5f53b7b47c098 100644
--- a/src/plugins/qtsupport/winceqtversionfactory.cpp
+++ b/src/plugins/qtsupport/winceqtversionfactory.cpp
@@ -73,7 +73,7 @@ BaseQtVersion *WinCeQtVersionFactory::create(const Utils::FileName &qmakePath, P
     if (!fi.exists() || !fi.isExecutable() || !fi.isFile())
         return 0;
 
-    QString ce_sdk = evaluator->values(QLatin1String("CE_SDK")).join(QLatin1String(" "));
+    QString ce_sdk = evaluator->values(QLatin1String("CE_SDK")).join(QLatin1Char(' '));
     QString ce_arch = evaluator->value(QLatin1String("CE_ARCH"));
 
     if (!ce_sdk.isEmpty() && !ce_arch.isEmpty())
diff --git a/src/plugins/remotelinux/remotelinuxdebugsupport.cpp b/src/plugins/remotelinux/remotelinuxdebugsupport.cpp
index 58cd4e5c1310a40710cd787cfad03b85f9d71a6a..5f903c011b0c90a356ccbf4c67146e0a40c90fc9 100644
--- a/src/plugins/remotelinux/remotelinuxdebugsupport.cpp
+++ b/src/plugins/remotelinux/remotelinuxdebugsupport.cpp
@@ -100,7 +100,7 @@ DebuggerStartParameters LinuxDeviceDebugSupport::startParameters(const AbstractR
     }
     if (aspect->useCppDebugger()) {
         params.languages |= CppLanguage;
-        params.processArgs = runConfig->arguments().join(QLatin1String(" "));
+        params.processArgs = runConfig->arguments().join(QLatin1Char(' '));
         params.startMode = AttachToRemoteServer;
         params.executable = runConfig->localExecutableFilePath();
         params.remoteChannel = device->sshParameters().host + QLatin1String(":-1");
diff --git a/src/plugins/remotelinux/remotelinuxrunconfigurationwidget.cpp b/src/plugins/remotelinux/remotelinuxrunconfigurationwidget.cpp
index 9ffc257b7a450130a8fa1c8dc6cf677c331309b4..28bf71bd058267884dea37a1f6c27b5eec0690fb 100644
--- a/src/plugins/remotelinux/remotelinuxrunconfigurationwidget.cpp
+++ b/src/plugins/remotelinux/remotelinuxrunconfigurationwidget.cpp
@@ -149,7 +149,7 @@ void RemoteLinuxRunConfigurationWidget::addGenericWidgets(QVBoxLayout *mainLayou
     altRemoteExeLayout->addWidget(&d->useAlternateCommandBox);
     d->genericWidgetsLayout.addRow(tr("Alternate executable on device:"), altRemoteExeWidget);
 
-    d->argsLineEdit.setText(d->runConfiguration->arguments().join(QLatin1String(" ")));
+    d->argsLineEdit.setText(d->runConfiguration->arguments().join(QLatin1Char(' ')));
     d->genericWidgetsLayout.addRow(tr("Arguments:"), &d->argsLineEdit);
 
     d->workingDirLineEdit.setPlaceholderText(tr("<default>"));
diff --git a/src/plugins/texteditor/findinfiles.cpp b/src/plugins/texteditor/findinfiles.cpp
index ae27fdc8ad3cf98e6c1161269217bd5865a1aeea..6708e895747e3d8b6daa5cb30454b9ebbc490b33 100644
--- a/src/plugins/texteditor/findinfiles.cpp
+++ b/src/plugins/texteditor/findinfiles.cpp
@@ -104,7 +104,7 @@ QString FindInFiles::toolTip() const
     //: %3 is filled by BaseFileFind::runNewSearch
     return tr("Path: %1\nFilter: %2\n%3")
             .arg(path().toUserOutput())
-            .arg(fileNameFilters().join(QLatin1String(",")));
+            .arg(fileNameFilters().join(QLatin1Char(',')));
 }
 
 QWidget *FindInFiles::createConfigWidget()
diff --git a/src/plugins/texteditor/generichighlighter/highlightersettings.cpp b/src/plugins/texteditor/generichighlighter/highlightersettings.cpp
index 5942482fcf0c11d38bc4def10b80fcdf068cb006..54685baf6d6668693db0809df4a79ebe4ee90fa6 100644
--- a/src/plugins/texteditor/generichighlighter/highlightersettings.cpp
+++ b/src/plugins/texteditor/generichighlighter/highlightersettings.cpp
@@ -166,7 +166,7 @@ void HighlighterSettings::setIgnoredFilesPatterns(const QString &patterns)
 
 QString HighlighterSettings::ignoredFilesPatterns() const
 {
-    return listFromExpressions().join(QLatin1String(","));
+    return listFromExpressions().join(QLatin1Char(','));
 }
 
 void HighlighterSettings::assignDefaultIgnoredPatterns()
diff --git a/src/plugins/valgrind/callgrind/callgrindparsedata.cpp b/src/plugins/valgrind/callgrind/callgrindparsedata.cpp
index 58be435cf72482eb121ec0d1cb1578baf5e3201c..9f12bc51746c884a0bb16852d2dfb93704dc7156 100644
--- a/src/plugins/valgrind/callgrind/callgrindparsedata.cpp
+++ b/src/plugins/valgrind/callgrind/callgrindparsedata.cpp
@@ -204,7 +204,7 @@ QString ParseData::prettyStringForEvent(const QString &event)
 
     // add original abbreviation
     prettyString << QLatin1Char('(') + event + QLatin1Char(')');
-    return prettyString.join(QString(QLatin1Char(' ')));
+    return prettyString.join(QLatin1Char(' '));
 }
 
 QStringList ParseData::events() const
diff --git a/src/plugins/valgrind/valgrindruncontrolfactory.cpp b/src/plugins/valgrind/valgrindruncontrolfactory.cpp
index 760948ab12248f2139bb4d5d3ea02128f9eecc9e..a5ad5a72def96332d7cd03b920c172d5f648a5d1 100644
--- a/src/plugins/valgrind/valgrindruncontrolfactory.cpp
+++ b/src/plugins/valgrind/valgrindruncontrolfactory.cpp
@@ -100,7 +100,7 @@ RunControl *ValgrindRunControlFactory::create(RunConfiguration *runConfiguration
         sp.startMode = StartRemote;
         sp.debuggee = rc2->remoteExecutableFilePath();
         sp.connParams = DeviceKitInformation::device(rc2->target()->kit())->sshParameters();
-        sp.debuggeeArgs = rc2->arguments().join(QLatin1String(" "));
+        sp.debuggeeArgs = rc2->arguments().join(QLatin1Char(' '));
     } else {
         QTC_ASSERT(false, return 0);
     }
diff --git a/src/plugins/vcsbase/commonsettingspage.cpp b/src/plugins/vcsbase/commonsettingspage.cpp
index 9923833ddac060da90bc9bcef69f92ecfcdbec9c..a4ebe50f61f4b9830a0897a4b300756bf3639b3d 100644
--- a/src/plugins/vcsbase/commonsettingspage.cpp
+++ b/src/plugins/vcsbase/commonsettingspage.cpp
@@ -96,7 +96,7 @@ void CommonSettingsWidget::updatePath()
 {
     Utils::Environment env = Utils::Environment::systemEnvironment();
     QStringList toAdd = Core::VcsManager::additionalToolsPath();
-    env.appendOrSetPath(toAdd.join(QString(Utils::HostOsInfo::pathListSeparator())));
+    env.appendOrSetPath(toAdd.join(Utils::HostOsInfo::pathListSeparator()));
     m_ui->sshPromptChooser->setEnvironment(env);
 }
 
diff --git a/src/shared/proparser/qmakeglobals.cpp b/src/shared/proparser/qmakeglobals.cpp
index e6f12d28ccaba3c1998300cc14ffb03d362912e0..1b2032d0f42625f4803a4fe25f4450760883dc3d 100644
--- a/src/shared/proparser/qmakeglobals.cpp
+++ b/src/shared/proparser/qmakeglobals.cpp
@@ -193,11 +193,11 @@ QMakeGlobals::ArgumentReturn QMakeGlobals::addCommandLineArguments(
 void QMakeGlobals::commitCommandLineArguments(QMakeCmdLineParserState &state)
 {
     if (!state.preconfigs.isEmpty())
-        state.precmds << (fL1S("CONFIG += ") + state.preconfigs.join(fL1S(" ")));
-    precmds = state.precmds.join(fL1S("\n"));
+        state.precmds << (fL1S("CONFIG += ") + state.preconfigs.join(QLatin1Char(' ')));
+    precmds = state.precmds.join(QLatin1Char('\n'));
     if (!state.postconfigs.isEmpty())
-        state.postcmds << (fL1S("CONFIG += ") + state.postconfigs.join(fL1S(" ")));
-    postcmds = state.postcmds.join(fL1S("\n"));
+        state.postcmds << (fL1S("CONFIG += ") + state.postconfigs.join(QLatin1Char(' ')));
+    postcmds = state.postcmds.join(QLatin1Char('\n'));
 
     if (xqmakespec.isEmpty())
         xqmakespec = qmakespec;
diff --git a/src/tools/buildoutputparser/main.cpp b/src/tools/buildoutputparser/main.cpp
index 2953567097eff80f00ad0dd66c68edde836e11f1..3f4b7f988f8803b43a2caaf7645516d1700064fd 100644
--- a/src/tools/buildoutputparser/main.cpp
+++ b/src/tools/buildoutputparser/main.cpp
@@ -93,7 +93,7 @@ int main(int argc, char *argv[])
     }
 
     if (!args.isEmpty())
-        qDebug("Ignoring extraneous parameters '%s'.\n", qPrintable(args.join(QLatin1String(" "))));
+        qDebug("Ignoring extraneous parameters '%s'.\n", qPrintable(args.join(QLatin1Char(' '))));
 
     QFile compilerOutputFile(filePath);
     if (!compilerOutputFile.open(QIODevice::ReadOnly)) {
diff --git a/src/tools/cplusplus-tools-utils/cplusplus-tools-utils.cpp b/src/tools/cplusplus-tools-utils/cplusplus-tools-utils.cpp
index 2db66cf2744597c884eb92d22ea7737d4392ee82..9e42f7077c0e5152289ec0788a7ea80f6c2c2bb5 100644
--- a/src/tools/cplusplus-tools-utils/cplusplus-tools-utils.cpp
+++ b/src/tools/cplusplus-tools-utils/cplusplus-tools-utils.cpp
@@ -57,7 +57,7 @@ void executeCommand(const QString &command, const QStringList &arguments, const
         exit(EXIT_FAILURE);
     }
 
-    const QString fullCommand = command + QLatin1Char(' ') + arguments.join(QLatin1String(" "));
+    const QString fullCommand = command + QLatin1Char(' ') + arguments.join(QLatin1Char(' '));
     if (verbose)
         out << "Executing: " << fullCommand << endl;
 
diff --git a/src/tools/sdktool/addkeysoperation.cpp b/src/tools/sdktool/addkeysoperation.cpp
index 114b366e9babab4f5ab4545809528e9ff1294331..20441cebe01157162efa675e10a3c170775059da 100644
--- a/src/tools/sdktool/addkeysoperation.cpp
+++ b/src/tools/sdktool/addkeysoperation.cpp
@@ -241,7 +241,7 @@ QVariantMap AddKeysOperation::addKeys(const QVariantMap &map, const KeyValuePair
         // insert
         Q_ASSERT(stack.count() == p.key.count());
         if (stack.last().contains(p.key.last())) {
-            std::cerr << "DEBUG: Adding key " << qPrintable(p.key.join(QLatin1String("/"))) << " which already exists." << std::endl;
+            std::cerr << "DEBUG: Adding key " << qPrintable(p.key.join(QLatin1Char('/'))) << " which already exists." << std::endl;
             return QVariantMap();
         }
         stack.last().insert(p.key.last(), p.value);
diff --git a/tests/auto/profilewriter/tst_profilewriter.cpp b/tests/auto/profilewriter/tst_profilewriter.cpp
index bd5fb173f304982cc463f25ddf0dda744ade9ec4..ad4abd658bd9f27fe8614bda31ecc4060fd55f99 100644
--- a/tests/auto/profilewriter/tst_profilewriter.cpp
+++ b/tests/auto/profilewriter/tst_profilewriter.cpp
@@ -457,7 +457,7 @@ void tst_ProFileWriter::adds()
     PW::putVarValues(proFile, &lines, values, var, PW::PutFlags(flags), scope);
     proFile->deref();
 
-    QCOMPARE(lines.join(QLatin1String("\n")), output);
+    QCOMPARE(lines.join(QLatin1Char('\n')), output);
 }
 
 void tst_ProFileWriter::removes_data()
@@ -628,7 +628,7 @@ void tst_ProFileWriter::removes()
     QmakeProjectManager::Internal::ProWriter::removeVarValues(proFile, &lines, values, vars);
     proFile->deref();
 
-    QCOMPARE(lines.join(QLatin1String("\n")), output);
+    QCOMPARE(lines.join(QLatin1Char('\n')), output);
 }
 
 void tst_ProFileWriter::multiVar()
@@ -657,7 +657,7 @@ void tst_ProFileWriter::multiVar()
     QmakeProjectManager::Internal::ProWriter::removeFiles(proFile, &lines, baseDir, files, vars);
     proFile->deref();
 
-    QCOMPARE(lines.join(QLatin1String("\n")), output);
+    QCOMPARE(lines.join(QLatin1Char('\n')), output);
 }
 
 void tst_ProFileWriter::addFiles()
@@ -665,7 +665,7 @@ void tst_ProFileWriter::addFiles()
     QString input = QLatin1String(
             "SOURCES = foo.cpp"
             );
-    QStringList lines = input.split(QLatin1String("\n"));
+    QStringList lines = input.split(QLatin1Char('\n'));
     QString output = QLatin1String(
             "SOURCES = foo.cpp \\\n"
             "    sub/bar.cpp"
@@ -680,7 +680,7 @@ void tst_ProFileWriter::addFiles()
             QLatin1String("SOURCES"));
     proFile->deref();
 
-    QCOMPARE(lines.join(QLatin1String("\n")), output);
+    QCOMPARE(lines.join(QLatin1Char('\n')), output);
 }
 
 void tst_ProFileWriter::removeFiles()
@@ -688,7 +688,7 @@ void tst_ProFileWriter::removeFiles()
     QString input = QLatin1String(
             "SOURCES = foo.cpp sub/bar.cpp"
             );
-    QStringList lines = input.split(QLatin1String("\n"));
+    QStringList lines = input.split(QLatin1Char('\n'));
     QString output = QLatin1String(
             "SOURCES = foo.cpp"
             );
@@ -702,7 +702,7 @@ void tst_ProFileWriter::removeFiles()
             QStringList() << QLatin1String("SOURCES") << QLatin1String("HEADERS"));
     proFile->deref();
 
-    QCOMPARE(lines.join(QLatin1String("\n")), output);
+    QCOMPARE(lines.join(QLatin1Char('\n')), output);
 }
 
 
diff --git a/tests/manual/process/main.cpp b/tests/manual/process/main.cpp
index c58715bff3018aa613c562f055e8e608feff6bd5..6c4df01a6baa215ab0dac80575c96c147846a77d 100644
--- a/tests/manual/process/main.cpp
+++ b/tests/manual/process/main.cpp
@@ -50,7 +50,7 @@ static const char usage[] =
 static int testSynchronous(const QString &cmd, const QStringList &args)
 {
     std::fprintf(stdout, "testSynchronous %s %s\n", qPrintable(cmd),
-                 qPrintable(args.join(QLatin1String(" "))));
+                 qPrintable(args.join(QLatin1Char(' '))));
     QProcess p;
     p.start(cmd, args);
     if (!p.waitForStarted())