Merge remote-tracking branch 'origin/5.0'

Change-Id: Ia018600fb257c9523fc9d15faa5bd8300840e3de

18 files changed, 522 insertions, 92 deletions

diff --git a/src/plugins/cpptools/clangdiagnosticconfig.cpp b/src/plugins/cpptools/clangdiagnosticconfig.cpp
index c31fc4f8ce..95ba5a7328 100644
--- a/src/plugins/cpptools/clangdiagnosticconfig.cpp
+++ b/src/plugins/cpptools/clangdiagnosticconfig.cpp
@@ -130,11 +130,26 @@ QString ClangDiagnosticConfig::clangTidyChecksAsJson() const
 {
     QString jsonString = "{Checks: '" + clangTidyChecks()
             + ",-clang-diagnostic-*', CheckOptions: [";
+
+    // The check is either listed verbatim or covered by the "<prefix>-*" pattern.
+    const auto checkIsEnabled = [this](const QString &check) {
+        for (QString subString = check; !subString.isEmpty();
+             subString.chop(subString.length() - subString.lastIndexOf('-'))) {
+            const int idx = m_clangTidyChecks.indexOf(subString);
+            if (idx == -1)
+                continue;
+            if (idx > 0 && m_clangTidyChecks.at(idx - 1) == '-')
+                continue;
+            if (subString == check || QStringView(m_clangTidyChecks)
+                    .mid(idx + subString.length()).startsWith(QLatin1String("-*"))) {
+                return true;
+            }
+        }
+        return false;
+    };
+
     for (auto it = m_tidyChecksOptions.cbegin(); it != m_tidyChecksOptions.cend(); ++it) {
-        const int idx = m_clangTidyChecks.indexOf(it.key());
-        if (idx == -1)
-            continue;
-        if (idx > 0 && m_clangTidyChecks.at(idx - 1) == '-')
+        if (!checkIsEnabled(it.key()))
             continue;
         QString optionString;
         for (auto optIt = it.value().begin(); optIt != it.value().end(); ++optIt) {
diff --git a/src/plugins/cpptools/compileroptionsbuilder.cpp b/src/plugins/cpptools/compileroptionsbuilder.cpp
index 030d2b16cd..09291830b3 100644
--- a/src/plugins/cpptools/compileroptionsbuilder.cpp
+++ b/src/plugins/cpptools/compileroptionsbuilder.cpp
@@ -165,6 +165,11 @@ void CompilerOptionsBuilder::add(const QString &arg, bool gccOnlyOption)
     add(QStringList{arg}, gccOnlyOption);
 }
 
+void CompilerOptionsBuilder::prepend(const QString &arg)
+{
+    m_options.prepend(arg);
+}
+
 void CompilerOptionsBuilder::add(const QStringList &args, bool gccOnlyOptions)
 {
     m_options.append((gccOnlyOptions && isClStyle()) ? clangArgsForCl(args) : args);
diff --git a/src/plugins/cpptools/compileroptionsbuilder.h b/src/plugins/cpptools/compileroptionsbuilder.h
index f81c515db0..c4d8589f17 100644
--- a/src/plugins/cpptools/compileroptionsbuilder.h
+++ b/src/plugins/cpptools/compileroptionsbuilder.h
@@ -85,6 +85,7 @@ public:
 
     // Add custom options
     void add(const QString &arg, bool gccOnlyOption = false);
+    void prepend(const QString &arg);
     void add(const QStringList &args, bool gccOnlyOptions = false);
     virtual void addExtraOptions() {}
 
diff --git a/src/plugins/cpptools/cppcodemodelsettings.cpp b/src/plugins/cpptools/cppcodemodelsettings.cpp
index 5c5113d004..c7cfc2d0cb 100644
--- a/src/plugins/cpptools/cppcodemodelsettings.cpp
+++ b/src/plugins/cpptools/cppcodemodelsettings.cpp
@@ -29,6 +29,9 @@
 #include "cpptoolsconstants.h"
 #include "cpptoolsreuse.h"
 
+#include <coreplugin/icore.h>
+#include <projectexplorer/project.h>
+
 #include <utils/algorithm.h>
 #include <utils/qtcassert.h>
 
@@ -61,8 +64,12 @@ static QString skipIndexingBigFilesKey()
 static QString indexerFileSizeLimitKey()
 { return QLatin1String(Constants::CPPTOOLS_INDEXER_FILE_SIZE_LIMIT); }
 
+static QString clangdSettingsKey() { return QLatin1String("ClangdSettings"); }
 static QString useClangdKey() { return QLatin1String("UseClangd"); }
 static QString clangdPathKey() { return QLatin1String("ClangdPath"); }
+static QString clangdIndexingKey() { return QLatin1String("ClangdIndexing"); }
+static QString clangdThreadLimitKey() { return QLatin1String("ClangdThreadLimit"); }
+static QString clangdUseGlobalSettingsKey() { return QLatin1String("useGlobalSettings"); }
 
 static FilePath g_defaultClangdFilePath;
 static FilePath fallbackClangdFilePath()
@@ -172,9 +179,6 @@ void CppCodeModelSettings::fromSettings(QSettings *s)
     const QVariant indexerFileSizeLimit = s->value(indexerFileSizeLimitKey(), 5);
     setIndexerFileSizeLimitInMb(indexerFileSizeLimit.toInt());
 
-    setUseClangd(s->value(useClangdKey(), false).toBool());
-    setClangdFilePath(FilePath::fromString(s->value(clangdPathKey()).toString()));
-
     s->endGroup();
 
     if (write)
@@ -198,8 +202,6 @@ void CppCodeModelSettings::toSettings(QSettings *s)
     s->setValue(interpretAmbiguousHeadersAsCHeadersKey(), interpretAmbigiousHeadersAsCHeaders());
     s->setValue(skipIndexingBigFilesKey(), skipIndexingBigFiles());
     s->setValue(indexerFileSizeLimitKey(), indexerFileSizeLimitInMb());
-    s->setValue(useClangdKey(), useClangd());
-    s->setValue(clangdPathKey(), m_clangdFilePath.toString());
 
     s->endGroup();
 
@@ -300,14 +302,113 @@ void CppCodeModelSettings::setEnableLowerClazyLevels(bool yesno)
     m_enableLowerClazyLevels = yesno;
 }
 
-void CppCodeModelSettings::setDefaultClangdPath(const Utils::FilePath &filePath)
+
+ClangdSettings &ClangdSettings::instance()
+{
+    static ClangdSettings settings;
+    return settings;
+}
+
+void ClangdSettings::setDefaultClangdPath(const Utils::FilePath &filePath)
 {
     g_defaultClangdFilePath = filePath;
 }
 
-FilePath CppCodeModelSettings::clangdFilePath() const
+FilePath ClangdSettings::clangdFilePath() const
 {
-    if (!m_clangdFilePath.isEmpty())
-        return m_clangdFilePath;
+    if (!m_data.executableFilePath.isEmpty())
+        return m_data.executableFilePath;
     return fallbackClangdFilePath();
 }
+
+void ClangdSettings::setData(const Data &data)
+{
+    if (this == &instance() && data != m_data) {
+        m_data = data;
+        saveSettings();
+        emit changed();
+    }
+}
+
+void ClangdSettings::loadSettings()
+{
+    m_data.fromMap(Core::ICore::settings()->value(clangdSettingsKey()).toMap());
+}
+
+void ClangdSettings::saveSettings()
+{
+    Core::ICore::settings()->setValue(clangdSettingsKey(), m_data.toMap());
+}
+
+#ifdef WITH_TESTS
+void ClangdSettings::setUseClangd(bool use) { instance().m_data.useClangd = use; }
+void ClangdSettings::setClangdFilePath(const Utils::FilePath &filePath)
+{
+    instance().m_data.executableFilePath = filePath;
+}
+#endif
+
+ClangdProjectSettings::ClangdProjectSettings(ProjectExplorer::Project *project) : m_project(project)
+{
+    loadSettings();
+}
+
+ClangdSettings::Data ClangdProjectSettings::settings() const
+{
+    if (m_useGlobalSettings)
+        return ClangdSettings::instance().data();
+    return m_customSettings;
+}
+
+void ClangdProjectSettings::setSettings(const ClangdSettings::Data &data)
+{
+    m_customSettings = data;
+    saveSettings();
+    emit ClangdSettings::instance().changed();
+}
+
+void ClangdProjectSettings::setUseGlobalSettings(bool useGlobal)
+{
+    m_useGlobalSettings = useGlobal;
+    saveSettings();
+    emit ClangdSettings::instance().changed();
+}
+
+void ClangdProjectSettings::loadSettings()
+{
+    if (!m_project)
+        return;
+    const QVariantMap data = m_project->namedSettings(clangdSettingsKey()).toMap();
+    m_useGlobalSettings = data.value(clangdUseGlobalSettingsKey(), true).toBool();
+    if (!m_useGlobalSettings)
+        m_customSettings.fromMap(data);
+}
+
+void ClangdProjectSettings::saveSettings()
+{
+    if (!m_project)
+        return;
+    QVariantMap data;
+    if (!m_useGlobalSettings)
+        data = m_customSettings.toMap();
+    data.insert(clangdUseGlobalSettingsKey(), m_useGlobalSettings);
+    m_project->setNamedSettings(clangdSettingsKey(), data);
+}
+
+QVariantMap ClangdSettings::Data::toMap() const
+{
+    QVariantMap map;
+    map.insert(useClangdKey(), useClangd);
+    map.insert(clangdPathKey(), executableFilePath.toString());
+    map.insert(clangdIndexingKey(), enableIndexing);
+    map.insert(clangdThreadLimitKey(), workerThreadLimit);
+    return map;
+}
+
+void ClangdSettings::Data::fromMap(const QVariantMap &map)
+{
+    useClangd = map.value(useClangdKey(), false).toBool();
+    executableFilePath = FilePath::fromString(map.value(clangdPathKey()).toString());
+    enableIndexing = map.value(clangdIndexingKey(), true).toBool();
+    workerThreadLimit = map.value(clangdThreadLimitKey(), 0).toInt();
+}
diff --git a/src/plugins/cpptools/cppcodemodelsettings.h b/src/plugins/cpptools/cppcodemodelsettings.h
index 5fc981e543..d4da25f3b0 100644
--- a/src/plugins/cpptools/cppcodemodelsettings.h
+++ b/src/plugins/cpptools/cppcodemodelsettings.h
@@ -38,6 +38,8 @@ QT_BEGIN_NAMESPACE
 class QSettings;
 QT_END_NAMESPACE
 
+namespace ProjectExplorer { class Project; }
+
 namespace CppTools {
 
 class CPPTOOLS_EXPORT CppCodeModelSettings : public QObject
@@ -78,13 +80,6 @@ public:
     int indexerFileSizeLimitInMb() const;
     void setIndexerFileSizeLimitInMb(int sizeInMB);
 
-    void setUseClangd(bool use) { m_useClangd = use; }
-    bool useClangd() const { return m_useClangd; }
-
-    static void setDefaultClangdPath(const Utils::FilePath &filePath);
-    void setClangdFilePath(const Utils::FilePath &filePath) { m_clangdFilePath = filePath; }
-    Utils::FilePath clangdFilePath() const;
-
     void setCategorizeFindReferences(bool categorize) { m_categorizeFindReferences = categorize; }
     bool categorizeFindReferences() const { return m_categorizeFindReferences; }
 
@@ -100,9 +95,84 @@ private:
     ClangDiagnosticConfigs m_clangCustomDiagnosticConfigs;
     Utils::Id m_clangDiagnosticConfigId;
     bool m_enableLowerClazyLevels = true; // For UI behavior only
-    Utils::FilePath m_clangdFilePath;
-    bool m_useClangd = false;
     bool m_categorizeFindReferences = false; // Ephemeral!
 };
 
+class CPPTOOLS_EXPORT ClangdSettings : public QObject
+{
+    Q_OBJECT
+public:
+    class CPPTOOLS_EXPORT Data
+    {
+    public:
+        QVariantMap toMap() const;
+        void fromMap(const QVariantMap &map);
+
+        Utils::FilePath executableFilePath;
+        int workerThreadLimit = 0;
+        bool useClangd = false;
+        bool enableIndexing = true;
+    };
+
+    ClangdSettings(const Data &data) : m_data(data) {}
+
+    static ClangdSettings &instance();
+    bool useClangd() const { return m_data.useClangd; }
+
+    static void setDefaultClangdPath(const Utils::FilePath &filePath);
+    Utils::FilePath clangdFilePath() const;
+    bool indexingEnabled() const { return m_data.enableIndexing; }
+    int workerThreadLimit() const { return m_data.workerThreadLimit; }
+
+    void setData(const Data &data);
+    Data data() const { return m_data; }
+
+#ifdef WITH_TESTS
+    static void setUseClangd(bool use);
+    static void setClangdFilePath(const Utils::FilePath &filePath);
+#endif
+
+signals:
+    void changed();
+
+private:
+    ClangdSettings() { loadSettings(); }
+
+    void loadSettings();
+    void saveSettings();
+
+    Data m_data;
+};
+
+inline bool operator==(const ClangdSettings::Data &s1, const ClangdSettings::Data &s2)
+{
+    return s1.useClangd == s2.useClangd
+            && s1.executableFilePath == s2.executableFilePath
+            && s1.workerThreadLimit == s2.workerThreadLimit
+            && s1.enableIndexing == s2.enableIndexing;
+}
+inline bool operator!=(const ClangdSettings::Data &s1, const ClangdSettings::Data &s2)
+{
+    return !(s1 == s2);
+}
+
+class CPPTOOLS_EXPORT ClangdProjectSettings
+{
+public:
+    ClangdProjectSettings(ProjectExplorer::Project *project);
+
+    ClangdSettings::Data settings() const;
+    void setSettings(const ClangdSettings::Data &data);
+    bool useGlobalSettings() const { return m_useGlobalSettings; }
+    void setUseGlobalSettings(bool useGlobal);
+
+private:
+    void loadSettings();
+    void saveSettings();
+
+    ProjectExplorer::Project * const m_project;
+    ClangdSettings::Data m_customSettings;
+    bool m_useGlobalSettings = true;
+};
+
 } // namespace CppTools
diff --git a/src/plugins/cpptools/cppcodemodelsettingspage.cpp b/src/plugins/cpptools/cppcodemodelsettingspage.cpp
index 00e7b8081a..dc04dc3cb8 100644
--- a/src/plugins/cpptools/cppcodemodelsettingspage.cpp
+++ b/src/plugins/cpptools/cppcodemodelsettingspage.cpp
@@ -33,7 +33,10 @@
 
 #include <coreplugin/icore.h>
 #include <utils/algorithm.h>
+#include <utils/pathchooser.h>
 
+#include <QFormLayout>
+#include <QSpinBox>
 #include <QTextStream>
 
 namespace CppTools {
@@ -100,8 +103,6 @@ void CppCodeModelSettingsWidget::setupClangCodeModelWidgets()
     const bool isClangActive = CppModelManager::instance()->isClangCodeModelActive();
     m_ui->clangCodeModelIsDisabledHint->setVisible(!isClangActive);
     m_ui->clangCodeModelIsEnabledHint->setVisible(isClangActive);
-    m_ui->clangdCheckBox->setVisible(isClangActive);
-    m_ui->clangdChooser->setVisible(isClangActive);
 
     for (int i = 0; i < m_ui->clangDiagnosticConfigsSelectionWidget->layout()->count(); ++i) {
         QWidget *widget = m_ui->clangDiagnosticConfigsSelectionWidget->layout()->itemAt(i)->widget();
@@ -120,16 +121,6 @@ void CppCodeModelSettingsWidget::setupGeneralWidgets()
 
     const bool ignorePch = m_settings->pchUsage() == CppCodeModelSettings::PchUse_None;
     m_ui->ignorePCHCheckBox->setChecked(ignorePch);
-
-    m_ui->clangdCheckBox->setChecked(m_settings->useClangd());
-    m_ui->clangdCheckBox->setToolTip(tr("Use clangd for locators and \"Find References\".\n"
-        "Changing this option does not affect projects that are already open."));
-    m_ui->clangdChooser->setExpectedKind(Utils::PathChooser::ExistingCommand);
-    m_ui->clangdChooser->setFilePath(codeModelSettings()->clangdFilePath());
-    m_ui->clangdChooser->setEnabled(m_ui->clangdCheckBox->isChecked());
-    connect(m_ui->clangdCheckBox, &QCheckBox::toggled, m_ui->clangdChooser, [this](bool checked) {
-        m_ui->clangdChooser->setEnabled(checked);
-    });
 }
 
 bool CppCodeModelSettingsWidget::applyClangCodeModelWidgetsToSettings() const
@@ -176,16 +167,6 @@ bool CppCodeModelSettingsWidget::applyGeneralWidgetsToSettings() const
         m_settings->setIndexerFileSizeLimitInMb(newFileSizeLimit);
         settingsChanged = true;
     }
-    const bool newUseClangd = m_ui->clangdCheckBox->isChecked();
-    if (m_settings->useClangd() != newUseClangd) {
-        m_settings->setUseClangd(newUseClangd);
-        settingsChanged = true;
-    }
-    const Utils::FilePath newClangdPath = m_ui->clangdChooser->rawFilePath();
-    if (m_settings->clangdFilePath() != newClangdPath) {
-        m_settings->setClangdFilePath(newClangdPath);
-        settingsChanged = true;
-    }
 
     const bool newIgnorePch = m_ui->ignorePCHCheckBox->isChecked();
     const bool previousIgnorePch = m_settings->pchUsage() == CppCodeModelSettings::PchUse_None;
@@ -210,5 +191,147 @@ CppCodeModelSettingsPage::CppCodeModelSettingsPage(CppCodeModelSettings *setting
     setWidgetCreator([settings] { return new CppCodeModelSettingsWidget(settings); });
 }
 
+class ClangdSettingsWidget::Private
+{
+public:
+    QCheckBox useClangdCheckBox;
+    QCheckBox indexingCheckBox;
+    QSpinBox threadLimitSpinBox;
+    Utils::PathChooser clangdChooser;
+};
+
+ClangdSettingsWidget::ClangdSettingsWidget(const ClangdSettings::Data &settingsData)
+    : d(new Private)
+{
+    const ClangdSettings settings(settingsData);
+    d->useClangdCheckBox.setText(tr("Use clangd (EXPERIMENTAL)"));
+    d->useClangdCheckBox.setChecked(settings.useClangd());
+    d->clangdChooser.setExpectedKind(Utils::PathChooser::ExistingCommand);
+    d->clangdChooser.setFilePath(settings.clangdFilePath());
+    d->clangdChooser.setEnabled(d->useClangdCheckBox.isChecked());
+    d->indexingCheckBox.setChecked(settings.indexingEnabled());
+    d->indexingCheckBox.setToolTip(tr(
+        "If background indexing is enabled, global symbol searches will yield\n"
+        "more accurate results, at the cost of additional CPU load when\n"
+        "the project is first opened."));
+    d->threadLimitSpinBox.setValue(settings.workerThreadLimit());
+    d->threadLimitSpinBox.setSpecialValueText("Automatic");
+
+    const auto layout = new QVBoxLayout(this);
+    layout->addWidget(&d->useClangdCheckBox);
+    const auto formLayout = new QFormLayout;
+    const auto chooserLabel = new QLabel(tr("Path to executable:"));
+    formLayout->addRow(chooserLabel, &d->clangdChooser);
+    const auto indexingLabel = new QLabel(tr("Enable background indexing:"));
+    formLayout->addRow(indexingLabel, &d->indexingCheckBox);
+    const auto threadLimitLayout = new QHBoxLayout;
+    threadLimitLayout->addWidget(&d->threadLimitSpinBox);
+    threadLimitLayout->addStretch(1);
+    const auto threadLimitLabel = new QLabel(tr("Set worker thread count:"));
+    formLayout->addRow(threadLimitLabel, threadLimitLayout);
+    layout->addLayout(formLayout);
+    layout->addStretch(1);
+
+    const auto toggleEnabled = [=](const bool checked) {
+        chooserLabel->setEnabled(checked);
+        d->clangdChooser.setEnabled(checked);
+        indexingLabel->setEnabled(checked);
+        d->indexingCheckBox.setEnabled(checked);
+        d->threadLimitSpinBox.setEnabled(checked);
+    };
+    connect(&d->useClangdCheckBox, &QCheckBox::toggled, toggleEnabled);
+    toggleEnabled(d->useClangdCheckBox.isChecked());
+    d->threadLimitSpinBox.setEnabled(d->useClangdCheckBox.isChecked());
+
+    connect(&d->useClangdCheckBox, &QCheckBox::toggled,
+            this, &ClangdSettingsWidget::settingsDataChanged);
+    connect(&d->indexingCheckBox, &QCheckBox::toggled,
+            this, &ClangdSettingsWidget::settingsDataChanged);
+    connect(&d->threadLimitSpinBox, qOverload<int>(&QSpinBox::valueChanged),
+            this, &ClangdSettingsWidget::settingsDataChanged);
+    connect(&d->clangdChooser, &Utils::PathChooser::pathChanged,
+            this, &ClangdSettingsWidget::settingsDataChanged);
+}
+
+ClangdSettingsWidget::~ClangdSettingsWidget()
+{
+    delete d;
+}
+
+ClangdSettings::Data ClangdSettingsWidget::settingsData() const
+{
+    ClangdSettings::Data data;
+    data.useClangd = d->useClangdCheckBox.isChecked();
+    data.executableFilePath = d->clangdChooser.filePath();
+    data.enableIndexing = d->indexingCheckBox.isChecked();
+    data.workerThreadLimit = d->threadLimitSpinBox.value();
+    return data;
+}
+
+class ClangdSettingsPageWidget final : public Core::IOptionsPageWidget
+{
+    Q_DECLARE_TR_FUNCTIONS(CppTools::Internal::ClangdSettingsWidget)
+
+public:
+    ClangdSettingsPageWidget() : m_widget(ClangdSettings::instance().data())
+    {
+        const auto layout = new QVBoxLayout(this);
+        layout->addWidget(&m_widget);
+    }
+
+private:
+    void apply() final { ClangdSettings::instance().setData(m_widget.settingsData()); }
+
+    ClangdSettingsWidget m_widget;
+};
+
+ClangdSettingsPage::ClangdSettingsPage()
+{
+    setId("K.Clangd");
+    setDisplayName(ClangdSettingsWidget::tr("Clangd"));
+    setCategory(Constants::CPP_SETTINGS_CATEGORY);
+    setWidgetCreator([] { return new ClangdSettingsPageWidget; });
+}
+
+
+class ClangdProjectSettingsWidget::Private
+{
+public:
+    Private(const ClangdProjectSettings &s) : settings(s), widget(s.settings()) {}
+
+    ClangdProjectSettings settings;
+    ClangdSettingsWidget widget;
+    QCheckBox useGlobalSettingsCheckBox;
+};
+
+ClangdProjectSettingsWidget::ClangdProjectSettingsWidget(const ClangdProjectSettings &settings)
+    : d(new Private(settings))
+{
+    const auto layout = new QVBoxLayout(this);
+    d->useGlobalSettingsCheckBox.setText(tr("Use global settings"));
+    layout->addWidget(&d->useGlobalSettingsCheckBox);
+    const auto separator = new QFrame;
+    separator->setFrameShape(QFrame::HLine);
+    layout->addWidget(separator);
+    layout->addWidget(&d->widget);
+
+    d->useGlobalSettingsCheckBox.setChecked(d->settings.useGlobalSettings());
+    d->widget.setEnabled(!d->settings.useGlobalSettings());
+    connect(&d->useGlobalSettingsCheckBox, &QCheckBox::toggled, [this](bool checked) {
+        d->widget.setEnabled(!checked);
+        d->settings.setUseGlobalSettings(checked);
+        if (!checked)
+            d->settings.setSettings(d->widget.settingsData());
+    });
+    connect(&d->widget, &ClangdSettingsWidget::settingsDataChanged, [this] {
+        d->settings.setSettings(d->widget.settingsData());
+    });
+}
+
+ClangdProjectSettingsWidget::~ClangdProjectSettingsWidget()
+{
+    delete d;
+}
+
 } // Internal
 } // CppTools
diff --git a/src/plugins/cpptools/cppcodemodelsettingspage.h b/src/plugins/cpptools/cppcodemodelsettingspage.h
index dd297af020..220645ca3e 100644
--- a/src/plugins/cpptools/cppcodemodelsettingspage.h
+++ b/src/plugins/cpptools/cppcodemodelsettingspage.h
@@ -38,5 +38,42 @@ public:
     explicit CppCodeModelSettingsPage(CppCodeModelSettings *settings);
 };
 
+class ClangdSettingsPage final : public Core::IOptionsPage
+{
+public:
+    explicit ClangdSettingsPage();
+};
+
+class ClangdSettingsWidget : public QWidget
+{
+    Q_OBJECT
+
+public:
+    ClangdSettingsWidget(const ClangdSettings::Data &settingsData);
+    ~ClangdSettingsWidget();
+
+    ClangdSettings::Data settingsData() const;
+
+signals:
+    void settingsDataChanged();
+
+private:
+    class Private;
+    Private * const d;
+};
+
+class ClangdProjectSettingsWidget : public QWidget
+{
+    Q_OBJECT
+
+public:
+    ClangdProjectSettingsWidget(const ClangdProjectSettings &settings);
+    ~ClangdProjectSettingsWidget();
+
+private:
+    class Private;
+    Private * const d;
+};
+
 } // Internal namespace
 } // CppTools namespace
diff --git a/src/plugins/cpptools/cppcodemodelsettingspage.ui b/src/plugins/cpptools/cppcodemodelsettingspage.ui
index 2362131cbe..90136f81bd 100644
--- a/src/plugins/cpptools/cppcodemodelsettingspage.ui
+++ b/src/plugins/cpptools/cppcodemodelsettingspage.ui
@@ -81,31 +81,7 @@
        </layout>
       </item>
       <item>
-       <layout class="QHBoxLayout" name="horizontalLayout_3">
-        <item>
-         <widget class="QCheckBox" name="clangdCheckBox">
-          <property name="text">
-           <string>Use clangd (EXPERIMENTAL)</string>
-          </property>
-         </widget>
-        </item>
-        <item>
-         <widget class="Utils::PathChooser" name="clangdChooser"/>
-        </item>
-        <item>
-         <spacer name="horizontalSpacer_3">
-          <property name="orientation">
-           <enum>Qt::Horizontal</enum>
-          </property>
-          <property name="sizeHint" stdset="0">
-           <size>
-            <width>40</width>
-            <height>20</height>
-           </size>
-          </property>
-         </spacer>
-        </item>
-       </layout>
+       <layout class="QHBoxLayout" name="horizontalLayout_3"/>
       </item>
      </layout>
     </widget>
@@ -174,11 +150,6 @@
    <extends>QWidget</extends>
    <header>cpptools/clangdiagnosticconfigsselectionwidget.h</header>
   </customwidget>
-  <customwidget>
-   <class>Utils::PathChooser</class>
-   <extends>QLineEdit</extends>
-   <header location="global">utils/pathchooser.h</header>
-  </customwidget>
  </customwidgets>
  <resources/>
  <connections/>
diff --git a/src/plugins/cpptools/cppheadersource_test.cpp b/src/plugins/cpptools/cppheadersource_test.cpp
index 37244f4fba..be0bdd03c2 100644
--- a/src/plugins/cpptools/cppheadersource_test.cpp
+++ b/src/plugins/cpptools/cppheadersource_test.cpp
@@ -100,7 +100,7 @@ void CppToolsPlugin::initTestCase()
 
 void CppToolsPlugin::cleanupTestCase()
 {
-    Utils::FileUtils::removeRecursively(Utils::FilePath::fromString(baseTestDir()));
+    Utils::FilePath::fromString(baseTestDir()).removeRecursively();
     CppFileSettings *fs = fileSettings();
     fs->headerSearchPaths.removeLast();
     fs->headerSearchPaths.removeLast();
diff --git a/src/plugins/cpptools/cppmodelmanager.cpp b/src/plugins/cpptools/cppmodelmanager.cpp
index fbee2cebbd..2366b5d4da 100644
--- a/src/plugins/cpptools/cppmodelmanager.cpp
+++ b/src/plugins/cpptools/cppmodelmanager.cpp
@@ -1145,7 +1145,8 @@ void CppModelManager::updateCppEditorDocuments(bool projectsUpdated) const
     }
 }
 
-QFuture<void> CppModelManager::updateProjectInfo(const ProjectInfo &newProjectInfo)
+QFuture<void> CppModelManager::updateProjectInfo(const ProjectInfo &newProjectInfo,
+                                                 const QSet<QString> &additionalFiles)
 {
     if (!newProjectInfo.isValid())
         return QFuture<void>();
@@ -1236,6 +1237,7 @@ QFuture<void> CppModelManager::updateProjectInfo(const ProjectInfo &newProjectIn
     // resolved includes that we could rely on.
     updateCppEditorDocuments(/*projectsUpdated = */ true);
 
+    filesToReindex.unite(additionalFiles);
     // Trigger reindexing
     const QFuture<void> indexingFuture = updateSourceFiles(filesToReindex,
                                                            ForcedProgressNotification);
@@ -1310,6 +1312,11 @@ bool CppModelManager::isCppEditor(Core::IEditor *editor)
     return editor->context().contains(ProjectExplorer::Constants::CXX_LANGUAGE_ID);
 }
 
+bool CppModelManager::supportsOutline(const TextEditor::TextDocument *document)
+{
+    return instance()->d->m_activeModelManagerSupport->supportsOutline(document);
+}
+
 bool CppModelManager::isClangCodeModelActive() const
 {
     return d->m_activeModelManagerSupport != d->m_builtinModelManagerSupport;
diff --git a/src/plugins/cpptools/cppmodelmanager.h b/src/plugins/cpptools/cppmodelmanager.h
index 98991f9c6c..81e8ec3710 100644
--- a/src/plugins/cpptools/cppmodelmanager.h
+++ b/src/plugins/cpptools/cppmodelmanager.h
@@ -116,7 +116,8 @@ public:
 
     QList<ProjectInfo> projectInfos() const;
     ProjectInfo projectInfo(ProjectExplorer::Project *project) const;
-    QFuture<void> updateProjectInfo(const ProjectInfo &newProjectInfo);
+    QFuture<void> updateProjectInfo(const ProjectInfo &newProjectInfo,
+                                    const QSet<QString> &additionalFiles = {});
 
     /// \return The project part with the given project file
     ProjectPart::Ptr projectPartForId(const QString &projectPartId) const override;
@@ -142,6 +143,7 @@ public:
     void emitAbstractEditorSupportRemoved(const QString &filePath);
 
     static bool isCppEditor(Core::IEditor *editor);
+    static bool supportsOutline(const TextEditor::TextDocument *document);
     bool isClangCodeModelActive() const;
 
     QSet<AbstractEditorSupport*> abstractEditorSupports() const;
diff --git a/src/plugins/cpptools/cppmodelmanagersupport.h b/src/plugins/cpptools/cppmodelmanagersupport.h
index ccf7ee83de..13b6108fab 100644
--- a/src/plugins/cpptools/cppmodelmanagersupport.h
+++ b/src/plugins/cpptools/cppmodelmanagersupport.h
@@ -61,6 +61,7 @@ public:
     virtual FollowSymbolInterface &followSymbolInterface() = 0;
     virtual RefactoringEngineInterface &refactoringEngineInterface() = 0;
     virtual std::unique_ptr<AbstractOverviewModel> createOverviewModel() = 0;
+    virtual bool supportsOutline(const TextEditor::TextDocument *) const { return true; }
 };
 
 class CPPTOOLS_EXPORT ModelManagerSupportProvider
diff --git a/src/plugins/cpptools/cppprojectupdater.cpp b/src/plugins/cpptools/cppprojectupdater.cpp
index 794fd7abe7..f34628af51 100644
--- a/src/plugins/cpptools/cppprojectupdater.cpp
+++ b/src/plugins/cpptools/cppprojectupdater.cpp
@@ -27,14 +27,21 @@
 
 #include "cppmodelmanager.h"
 #include "cppprojectinfogenerator.h"
+#include "generatedcodemodelsupport.h"
+
+#include <coreplugin/progressmanager/progressmanager.h>
 
 #include <projectexplorer/toolchainmanager.h>
 
+#include <utils/algorithm.h>
+#include <utils/fileutils.h>
 #include <utils/qtcassert.h>
 #include <utils/runextensions.h>
 
 #include <QFutureInterface>
 
+using namespace ProjectExplorer;
+
 namespace CppTools {
 
 CppProjectUpdater::CppProjectUpdater()
@@ -46,11 +53,25 @@ CppProjectUpdater::CppProjectUpdater()
     m_futureSynchronizer.setCancelOnWait(true);
 }
 
-void CppProjectUpdater::update(const ProjectExplorer::ProjectUpdateInfo &projectUpdateInfo)
+CppProjectUpdater::~CppProjectUpdater()
+{
+    cancel();
+}
+
+void CppProjectUpdater::update(const ProjectUpdateInfo &projectUpdateInfo)
+{
+    update(projectUpdateInfo, {});
+}
+
+void CppProjectUpdater::update(const ProjectUpdateInfo &projectUpdateInfo,
+                               const QList<ProjectExplorer::ExtraCompiler *> &extraCompilers)
 {
     // Stop previous update.
     cancel();
 
+    m_extraCompilers = Utils::transform(extraCompilers, [](ExtraCompiler *compiler) {
+        return QPointer<ExtraCompiler>(compiler);
+    });
     m_projectUpdateInfo = projectUpdateInfo;
 
     // Ensure that we do not operate on a deleted toolchain.
@@ -68,15 +89,52 @@ void CppProjectUpdater::update(const ProjectExplorer::ProjectUpdateInfo &project
     });
     m_generateFutureWatcher.setFuture(generateFuture);
     m_futureSynchronizer.addFuture(generateFuture);
+
+    // extra compilers
+    for (QPointer<ExtraCompiler> compiler : qAsConst(m_extraCompilers)) {
+        if (compiler->isDirty()) {
+            auto watcher = new QFutureWatcher<void>;
+            // queued connection to delay after the extra compiler updated its result contents,
+            // which is also done in the main thread when compiler->run() finished
+            connect(watcher, &QFutureWatcherBase::finished,
+                    this, [this, watcher] {
+                        m_projectUpdateFutureInterface->setProgressValue(
+                            m_projectUpdateFutureInterface->progressValue() + 1);
+                        m_extraCompilersFutureWatchers.remove(watcher);
+                        watcher->deleteLater();
+                        if (!watcher->isCanceled())
+                            checkForExtraCompilersFinished();
+                    },
+                    Qt::QueuedConnection);
+            m_extraCompilersFutureWatchers += watcher;
+            watcher->setFuture(QFuture<void>(compiler->run()));
+            m_futureSynchronizer.addFuture(watcher->future());
+        }
+    }
+
+    m_projectUpdateFutureInterface.reset(new QFutureInterface<void>);
+    m_projectUpdateFutureInterface->setProgressRange(0, m_extraCompilersFutureWatchers.size()
+                                                        + 1 /*generateFuture*/);
+    m_projectUpdateFutureInterface->setProgressValue(0);
+    m_projectUpdateFutureInterface->reportStarted();
+    Core::ProgressManager::addTask(m_projectUpdateFutureInterface->future(),
+                                   tr("Preparing C++ Code Model"),
+                                   "CppProjectUpdater");
 }
 
 void CppProjectUpdater::cancel()
 {
+    if (m_projectUpdateFutureInterface && m_projectUpdateFutureInterface->isRunning())
+        m_projectUpdateFutureInterface->reportFinished();
     m_generateFutureWatcher.setFuture({});
+    m_isProjectInfoGenerated = false;
+    qDeleteAll(m_extraCompilersFutureWatchers);
+    m_extraCompilersFutureWatchers.clear();
+    m_extraCompilers.clear();
     m_futureSynchronizer.cancelAllFutures();
 }
 
-void CppProjectUpdater::onToolChainRemoved(ProjectExplorer::ToolChain *t)
+void CppProjectUpdater::onToolChainRemoved(ToolChain *t)
 {
     QTC_ASSERT(t, return);
     if (t == m_projectUpdateInfo.cToolChain || t == m_projectUpdateInfo.cxxToolChain)
@@ -93,8 +151,33 @@ void CppProjectUpdater::onProjectInfoGenerated()
     if (m_generateFutureWatcher.isCanceled() || m_generateFutureWatcher.future().resultCount() < 1)
         return;
 
-    auto updateFuture = CppModelManager::instance()->updateProjectInfo(
-        m_generateFutureWatcher.result());
+    m_projectUpdateFutureInterface->setProgressValue(m_projectUpdateFutureInterface->progressValue()
+                                                     + 1);
+    m_isProjectInfoGenerated = true;
+    checkForExtraCompilersFinished();
+}
+
+void CppProjectUpdater::checkForExtraCompilersFinished()
+{
+    if (!m_extraCompilersFutureWatchers.isEmpty() || !m_isProjectInfoGenerated)
+        return; // still need to wait
+
+    m_projectUpdateFutureInterface->reportFinished();
+    m_projectUpdateFutureInterface.reset();
+
+    QList<ExtraCompiler *> extraCompilers;
+    QSet<QString> compilerFiles;
+    for (const QPointer<ExtraCompiler> &compiler : qAsConst(m_extraCompilers)) {
+        if (compiler) {
+            extraCompilers += compiler.data();
+            compilerFiles += Utils::transform<QSet>(compiler->targets(), &Utils::FilePath::toString);
+        }
+    }
+    GeneratedCodeModelSupport::update(extraCompilers);
+    m_extraCompilers.clear();
+
+    auto updateFuture = CppModelManager::instance()
+                            ->updateProjectInfo(m_generateFutureWatcher.result(), compilerFiles);
     m_futureSynchronizer.addFuture(updateFuture);
 }
 
diff --git a/src/plugins/cpptools/cppprojectupdater.h b/src/plugins/cpptools/cppprojectupdater.h
index 6b994871ef..c356ab63d1 100644
--- a/src/plugins/cpptools/cppprojectupdater.h
+++ b/src/plugins/cpptools/cppprojectupdater.h
@@ -29,6 +29,7 @@
 #include "cpptools_global.h"
 #include "projectinfo.h"
 
+#include <projectexplorer/extracompiler.h>
 #include <utils/futuresynchronizer.h>
 
 #include <QFutureWatcher>
@@ -54,18 +55,26 @@ class CPPTOOLS_EXPORT CppProjectUpdater final : public QObject, public CppProjec
 
 public:
     CppProjectUpdater();
+    ~CppProjectUpdater() override;
 
     void update(const ProjectExplorer::ProjectUpdateInfo &projectUpdateInfo) override;
+    void update(const ProjectExplorer::ProjectUpdateInfo &projectUpdateInfo,
+                const QList<ProjectExplorer::ExtraCompiler *> &extraCompilers);
     void cancel() override;
 
 private:
     void onToolChainRemoved(ProjectExplorer::ToolChain *);
     void onProjectInfoGenerated();
+    void checkForExtraCompilersFinished();
 
 private:
     ProjectExplorer::ProjectUpdateInfo m_projectUpdateInfo;
+    QList<QPointer<ProjectExplorer::ExtraCompiler>> m_extraCompilers;
 
     QFutureWatcher<ProjectInfo> m_generateFutureWatcher;
+    bool m_isProjectInfoGenerated = false;
+    QSet<QFutureWatcher<void> *> m_extraCompilersFutureWatchers;
+    std::unique_ptr<QFutureInterface<void>> m_projectUpdateFutureInterface;
     Utils::FutureSynchronizer m_futureSynchronizer;
 };
 
diff --git a/src/plugins/cpptools/cpptoolsconstants.h b/src/plugins/cpptools/cpptoolsconstants.h
index 7ee83c1f70..9b5b1c6f64 100644
--- a/src/plugins/cpptools/cpptoolsconstants.h
+++ b/src/plugins/cpptools/cpptoolsconstants.h
@@ -95,14 +95,6 @@ const char LOCATOR_FILTER_DISPLAY_NAME[] = QT_TRANSLATE_NOOP("CppTools", "C++ Cl
 const char SYMBOLS_FIND_FILTER_ID[] = "Symbols";
 const char SYMBOLS_FIND_FILTER_DISPLAY_NAME[] = QT_TRANSLATE_NOOP("CppTools", "C++ Symbols");
 
-// CLANG-UPGRADE-CHECK: Checks/update URLs.
-//
-// Upgrade the version in the URL. Note that we cannot use the macro
-// CLANG_VERSION here because it might denote a version that was not yet
-// released (e.g. 6.0.1, but only 6.0.0 was released).
-constexpr const char TIDY_DOCUMENTATION_URL_TEMPLATE[]
-    = "https://releases.llvm.org/11.0.0/tools/clang/tools/extra/docs/clang-tidy/checks/%1.html";
-
 constexpr const char CLANG_STATIC_ANALYZER_DOCUMENTATION_URL[]
     = "https://clang-analyzer.llvm.org/available_checks.html";
 
diff --git a/src/plugins/cpptools/cpptoolsplugin.cpp b/src/plugins/cpptools/cpptoolsplugin.cpp
index c5796e0dba..1e77501c0f 100644
--- a/src/plugins/cpptools/cpptoolsplugin.cpp
+++ b/src/plugins/cpptools/cpptoolsplugin.cpp
@@ -49,6 +49,7 @@
 #include <cppeditor/cppeditorconstants.h>
 #include <extensionsystem/pluginmanager.h>
 #include <projectexplorer/project.h>
+#include <projectexplorer/projectpanelfactory.h>
 #include <projectexplorer/projecttree.h>
 
 #include <utils/algorithm.h>
@@ -86,6 +87,7 @@ public:
     ~CppToolsPluginPrivate()
     {
         ExtensionSystem::PluginManager::removeObject(&m_cppProjectUpdaterFactory);
+        delete m_clangdSettingsPage;
     }
 
     StringTable stringTable;
@@ -95,6 +97,7 @@ public:
     CppFileSettings m_fileSettings;
     CppFileSettingsPage m_cppFileSettingsPage{&m_fileSettings};
     CppCodeModelSettingsPage m_cppCodeModelSettingsPage{&m_codeModelSettings};
+    ClangdSettingsPage *m_clangdSettingsPage = nullptr;
     CppCodeStyleSettingsPage m_cppCodeStyleSettingsPage;
     CppProjectUpdaterFactory m_cppProjectUpdaterFactory;
 };
@@ -208,6 +211,14 @@ bool CppToolsPlugin::initialize(const QStringList &arguments, QString *error)
                 tr("Insert \"#pragma once\" instead of \"#ifndef\" include guards into header file"),
                 [] { return usePragmaOnce() ? QString("true") : QString(); });
 
+    const auto panelFactory = new ProjectExplorer::ProjectPanelFactory;
+    panelFactory->setPriority(100);
+    panelFactory->setDisplayName(tr("Clangd"));
+    panelFactory->setCreateWidgetFunction([](ProjectExplorer::Project *project) {
+        return new ClangdProjectSettingsWidget(project);
+    });
+    ProjectExplorer::ProjectPanelFactory::registerFactory(panelFactory);
+
     return true;
 }
 
@@ -218,6 +229,8 @@ void CppToolsPlugin::extensionsInitialized()
     d->m_fileSettings.fromSettings(ICore::settings());
     if (!d->m_fileSettings.applySuffixesToMimeDB())
         qWarning("Unable to apply cpp suffixes to mime database (cpp mime types not found).\n");
+    if (CppModelManager::instance()->isClangCodeModelActive())
+        d->m_clangdSettingsPage = new ClangdSettingsPage;
 }
 
 CppCodeModelSettings *CppToolsPlugin::codeModelSettings()
diff --git a/src/plugins/cpptools/cpptoolstestcase.cpp b/src/plugins/cpptools/cpptoolstestcase.cpp
index c80a4a7cff..e9a6e85d0d 100644
--- a/src/plugins/cpptools/cpptoolstestcase.cpp
+++ b/src/plugins/cpptools/cpptoolstestcase.cpp
@@ -312,7 +312,7 @@ QString TemporaryDir::createFile(const QByteArray &relativePath, const QByteArra
     if (relativePathString.isEmpty() || QFileInfo(relativePathString).isAbsolute())
         return QString();
 
-    const QString filePath = m_temporaryDir.path() + QLatin1Char('/') + relativePathString;
+    const QString filePath = m_temporaryDir.filePath(relativePathString).path();
     if (!TestCase::writeFile(filePath, contents))
         return QString();
     return filePath;
@@ -368,7 +368,7 @@ TemporaryCopiedDir::TemporaryCopiedDir(const QString &sourceDirPath)
 
 QString TemporaryCopiedDir::absolutePath(const QByteArray &relativePath) const
 {
-    return m_temporaryDir.path() + QLatin1Char('/') + QString::fromUtf8(relativePath);
+    return m_temporaryDir.filePath(QString::fromUtf8(relativePath)).path();
 }
 
 FileWriterAndRemover::FileWriterAndRemover(const QString &filePath, const QByteArray &contents)
diff --git a/src/plugins/cpptools/cpptoolstestcase.h b/src/plugins/cpptools/cpptoolstestcase.h
index 08ae5b7c70..d03a1b297c 100644
--- a/src/plugins/cpptools/cpptoolstestcase.h
+++ b/src/plugins/cpptools/cpptoolstestcase.h
@@ -155,7 +155,7 @@ public:
     TemporaryDir();
 
     bool isValid() const { return m_isValid; }
-    QString path() const { return m_temporaryDir.path(); }
+    QString path() const { return m_temporaryDir.path().path(); }
 
     QString createFile(const QByteArray &relativePath, const QByteArray &contents);