diff --git a/src/plugins/clangcodemodel/clangeditordocumentprocessor.cpp b/src/plugins/clangcodemodel/clangeditordocumentprocessor.cpp
index 05874085c08..1cb6790b44c 100644
--- a/src/plugins/clangcodemodel/clangeditordocumentprocessor.cpp
+++ b/src/plugins/clangcodemodel/clangeditordocumentprocessor.cpp
@@ -280,6 +280,13 @@ void ClangEditorDocumentProcessor::editorDocumentTimerRestarted()
     m_updateTranslationUnitTimer.stop(); // Wait for the next call to run().
 }
 
+void ClangEditorDocumentProcessor::setParserConfig(
+        const CppTools::BaseEditorDocumentParser::Configuration config)
+{
+    m_parser->setConfiguration(config);
+    m_builtinProcessor.parser()->setConfiguration(config);
+}
+
 ClangBackEnd::FileContainer ClangEditorDocumentProcessor::fileContainerWithArguments() const
 {
     return fileContainerWithArguments(m_projectPart.data());
diff --git a/src/plugins/clangcodemodel/clangeditordocumentprocessor.h b/src/plugins/clangcodemodel/clangeditordocumentprocessor.h
index 7f30299391d..ad598957641 100644
--- a/src/plugins/clangcodemodel/clangeditordocumentprocessor.h
+++ b/src/plugins/clangcodemodel/clangeditordocumentprocessor.h
@@ -82,6 +82,8 @@ public:
 
     void editorDocumentTimerRestarted() override;
 
+    void setParserConfig(const CppTools::BaseEditorDocumentParser::Configuration config) override;
+
     ClangBackEnd::FileContainer fileContainerWithArguments() const;
 
     void clearDiagnosticsWithFixIts();
diff --git a/src/plugins/cppeditor/cppeditor.cpp b/src/plugins/cppeditor/cppeditor.cpp
index be81648c233..a2c73661ff3 100644
--- a/src/plugins/cppeditor/cppeditor.cpp
+++ b/src/plugins/cppeditor/cppeditor.cpp
@@ -131,6 +131,8 @@ public:
 
     QScopedPointer<FollowSymbolUnderCursor> m_followSymbolUnderCursor;
 
+    QAction *m_parseContextAction = nullptr;
+    ParseContextWidget *m_parseContextWidget = nullptr;
     QToolButton *m_preprocessorButton = nullptr;
     MinimizableInfoBars::Actions m_showInfoBarActions;
 
@@ -222,7 +224,7 @@ void CppEditorWidget::finalizeInitialization()
         d->m_cppSelectionChanger.onCursorPositionChanged(textCursor());
     });
 
-    // Tool bar creation
+    // Toolbar: '#' Button
     d->m_preprocessorButton = new QToolButton(this);
     d->m_preprocessorButton->setText(QLatin1String("#"));
     Command *cmd = ActionManager::command(Constants::OPEN_PREPROCESSOR_DIALOG);
@@ -231,13 +233,25 @@ void CppEditorWidget::finalizeInitialization()
     connect(d->m_preprocessorButton, &QAbstractButton::clicked, this, &CppEditorWidget::showPreProcessorWidget);
     insertExtraToolBarWidget(TextEditorWidget::Left, d->m_preprocessorButton);
 
-    // Actions to show minimized info bars
+    // Toolbar: Actions to show minimized info bars
     d->m_showInfoBarActions = MinimizableInfoBars::createShowInfoBarActions([this](QWidget *w) {
         return this->insertExtraToolBarWidget(TextEditorWidget::Left, w);
     });
     connect(&cppEditorDocument()->minimizableInfoBars(), &MinimizableInfoBars::showAction,
             this, &CppEditorWidget::onShowInfoBarAction);
 
+    // Toolbar: Parse context
+    ParseContextModel &parseContextModel = cppEditorDocument()->parseContextModel();
+    d->m_parseContextWidget = new ParseContextWidget(parseContextModel, this);
+    d->m_parseContextAction = insertExtraToolBarWidget(TextEditorWidget::Left,
+                                                       d->m_parseContextWidget);
+    d->m_parseContextAction->setVisible(false);
+    connect(&parseContextModel, &ParseContextModel::updated,
+            this, [this](bool areMultipleAvailable) {
+        d->m_parseContextAction->setVisible(areMultipleAvailable);
+    });
+
+    // Toolbar: Outline/Overview combo box
     insertExtraToolBarWidget(TextEditorWidget::Left, d->m_cppEditorOutline->widget());
 }
 
@@ -252,6 +266,10 @@ void CppEditorWidget::finalizeInitializationAfterDuplication(TextEditorWidget *o
     d->m_cppEditorOutline->update();
     const Id selectionKind = CodeWarningsSelection;
     setExtraSelections(selectionKind, cppEditorWidget->extraSelections(selectionKind));
+
+    d->m_parseContextWidget->syncToModel();
+    d->m_parseContextAction->setVisible(
+                d->m_cppEditorDocument->parseContextModel().areMultipleAvailable());
 }
 
 CppEditorWidget::~CppEditorWidget()
@@ -972,20 +990,12 @@ void CppEditorWidget::abortDeclDefLink()
 
 void CppEditorWidget::showPreProcessorWidget()
 {
-    const Utils::FileName fileName = textDocument()->filePath();
+    const QString filePath = textDocument()->filePath().toString();
 
-    // Check if this editor belongs to a project
-    QList<ProjectPart::Ptr> projectParts = d->m_modelManager->projectPart(fileName);
-    if (projectParts.isEmpty())
-        projectParts = d->m_modelManager->projectPartFromDependencies(fileName);
-    if (projectParts.isEmpty())
-        projectParts << d->m_modelManager->fallbackProjectPart();
-
-    CppPreProcessorDialog preProcessorDialog(this, textDocument()->filePath().toString(), projectParts);
-    if (preProcessorDialog.exec() == QDialog::Accepted) {
-        cppEditorDocument()->setPreprocessorSettings(
-                    preProcessorDialog.projectPart(),
-                    preProcessorDialog.additionalPreProcessorDirectives().toUtf8());
+    CppPreProcessorDialog dialog(filePath, this);
+    if (dialog.exec() == QDialog::Accepted) {
+        const QByteArray extraDirectives = dialog.extraPreprocessorDirectives().toUtf8();
+        cppEditorDocument()->setExtraPreprocessorDirectives(extraDirectives);
         cppEditorDocument()->scheduleProcessDocument();
     }
 }
diff --git a/src/plugins/cppeditor/cppeditor.pro b/src/plugins/cppeditor/cppeditor.pro
index 5ffc65229d2..d7ae058c175 100644
--- a/src/plugins/cppeditor/cppeditor.pro
+++ b/src/plugins/cppeditor/cppeditor.pro
@@ -17,6 +17,7 @@ HEADERS += \
     cppfunctiondecldeflink.h \
     cpphighlighter.h \
     cpphoverhandler.h \
+    cppparsecontext.h \
     cppincludehierarchy.h \
     cppinsertvirtualmethods.h \
     cpplocalrenaming.h \
@@ -46,6 +47,7 @@ SOURCES += \
     cppfunctiondecldeflink.cpp \
     cpphighlighter.cpp \
     cpphoverhandler.cpp \
+    cppparsecontext.cpp \
     cppincludehierarchy.cpp \
     cppinsertvirtualmethods.cpp \
     cpplocalrenaming.cpp \
diff --git a/src/plugins/cppeditor/cppeditor.qbs b/src/plugins/cppeditor/cppeditor.qbs
index d1d92ed29b3..e9cd5ed9e12 100644
--- a/src/plugins/cppeditor/cppeditor.qbs
+++ b/src/plugins/cppeditor/cppeditor.qbs
@@ -43,6 +43,7 @@ QtcPlugin {
         "cppminimizableinfobars.cpp", "cppminimizableinfobars.h",
         "cppoutline.cpp", "cppoutline.h",
         "cpppreprocessordialog.cpp", "cpppreprocessordialog.h", "cpppreprocessordialog.ui",
+        "cppparsecontext.cpp", "cppparsecontext.h",
         "cppquickfix.cpp", "cppquickfix.h",
         "cppquickfixassistant.cpp", "cppquickfixassistant.h",
         "cppquickfixes.cpp", "cppquickfixes.h",
diff --git a/src/plugins/cppeditor/cppeditorconstants.h b/src/plugins/cppeditor/cppeditorconstants.h
index 084a4f63c4e..44c1d2674be 100644
--- a/src/plugins/cppeditor/cppeditorconstants.h
+++ b/src/plugins/cppeditor/cppeditorconstants.h
@@ -37,6 +37,7 @@ const char RENAME_SYMBOL_UNDER_CURSOR[] = "CppEditor.RenameSymbolUnderCursor";
 const char FIND_USAGES[] = "CppEditor.FindUsages";
 const char OPEN_PREPROCESSOR_DIALOG[] = "CppEditor.OpenPreprocessorDialog";
 const char ERRORS_IN_HEADER_FILES[] = "CppEditor.ErrorsInHeaderFiles";
+const char MULTIPLE_PARSE_CONTEXTS_AVAILABLE[] = "CppEditor.MultipleParseContextsAvailable";
 const char NO_PROJECT_CONFIGURATION[] = "CppEditor.NoProjectConfiguration";
 const char M_REFACTORING_MENU_INSERTION_POINT[] = "CppEditor.RefactorGroup";
 const char UPDATE_CODEMODEL[] = "CppEditor.UpdateCodeModel";
@@ -50,7 +51,8 @@ const char OPEN_INCLUDE_HIERARCHY[] = "CppEditor.OpenIncludeHierarchy";
 
 const char CPP_SNIPPETS_GROUP_ID[] = "C++";
 
-const char CPP_PREPROCESSOR_PROJECT_PREFIX[] = "CppPreprocessorProject-";
+const char EXTRA_PREPROCESSOR_DIRECTIVES[] = "CppEditor.ExtraPreprocessorDirectives-";
+const char PREFERRED_PARSE_CONTEXT[] = "CppEditor.PreferredParseContext-";
 
 } // namespace Constants
 } // namespace CppEditor
diff --git a/src/plugins/cppeditor/cppeditordocument.cpp b/src/plugins/cppeditor/cppeditordocument.cpp
index 3c66c36baf5..6066e8da584 100644
--- a/src/plugins/cppeditor/cppeditordocument.cpp
+++ b/src/plugins/cppeditor/cppeditordocument.cpp
@@ -30,6 +30,8 @@
 #include "cpphighlighter.h"
 #include "cppquickfixassistant.h"
 
+#include <coreplugin/infobar.h>
+
 #include <cpptools/baseeditordocumentparser.h>
 #include <cpptools/builtineditordocumentprocessor.h>
 #include <cpptools/cppcodeformatter.h>
@@ -115,6 +117,9 @@ CppEditorDocument::CppEditorDocument()
     connect(this, &IDocument::filePathChanged,
             this, &CppEditorDocument::onFilePathChanged);
 
+    connect(&m_parseContextModel, &ParseContextModel::preferredParseContextChanged,
+            this, &CppEditorDocument::reparseWithPreferredParseContext);
+
     // See also onFilePathChanged() for more initialization
 }
 
@@ -204,6 +209,21 @@ void CppEditorDocument::onReloadFinished()
     m_fileIsBeingReloaded = false;
 }
 
+void CppEditorDocument::reparseWithPreferredParseContext(const QString &parseContextId)
+{
+    using namespace CppTools;
+
+    // Update parser
+    setPreferredParseContext(parseContextId);
+
+    // Remember the setting
+    const QString key = Constants::PREFERRED_PARSE_CONTEXT + filePath().toString();
+    ProjectExplorer::SessionManager::setValue(key, parseContextId);
+
+    // Reprocess
+    scheduleProcessDocument();
+}
+
 void CppEditorDocument::onFilePathChanged(const Utils::FileName &oldPath,
                                           const Utils::FileName &newPath)
 {
@@ -222,7 +242,8 @@ void CppEditorDocument::onFilePathChanged(const Utils::FileName &oldPath,
         m_editorDocumentHandle.reset(new CppEditorDocumentHandleImpl(this));
 
         resetProcessor();
-        updatePreprocessorSettings();
+        applyPreferredParseContextFromSettings();
+        applyExtraPreprocessorDirectivesFromSettings();
         m_processorRevision = document()->revision();
         processDocument();
     }
@@ -256,34 +277,51 @@ void CppEditorDocument::resetProcessor()
     processor(); // creates a new processor
 }
 
-void CppEditorDocument::updatePreprocessorSettings()
+void CppEditorDocument::applyPreferredParseContextFromSettings()
 {
     if (filePath().isEmpty())
         return;
 
-    const QString prefix = QLatin1String(Constants::CPP_PREPROCESSOR_PROJECT_PREFIX);
-    const QString &projectPartId = ProjectExplorer::SessionManager::value(
-                prefix + filePath().toString()).toString();
-    const QString directivesKey = projectPartId + QLatin1Char(',') + filePath().toString();
-    const QByteArray additionalDirectives = ProjectExplorer::SessionManager::value(
-                directivesKey).toString().toUtf8();
+    const QString key = Constants::PREFERRED_PARSE_CONTEXT + filePath().toString();
+    const QString parseContextId = ProjectExplorer::SessionManager::value(key).toString();
 
-    setPreprocessorSettings(mm()->projectPartForId(projectPartId), additionalDirectives);
+    setPreferredParseContext(parseContextId);
 }
 
-void CppEditorDocument::setPreprocessorSettings(const CppTools::ProjectPart::Ptr &projectPart,
-                                                const QByteArray &defines)
+void CppEditorDocument::applyExtraPreprocessorDirectivesFromSettings()
+{
+    if (filePath().isEmpty())
+        return;
+
+    const QString key = Constants::EXTRA_PREPROCESSOR_DIRECTIVES + filePath().toString();
+    const QByteArray directives = ProjectExplorer::SessionManager::value(key).toString().toUtf8();
+
+    setExtraPreprocessorDirectives(directives);
+}
+
+void CppEditorDocument::setExtraPreprocessorDirectives(const QByteArray &directives)
 {
     const auto parser = processor()->parser();
     QTC_ASSERT(parser, return);
-    if (parser->projectPartInfo().projectPart != projectPart
-            || parser->configuration().editorDefines != defines) {
-        CppTools::BaseEditorDocumentParser::Configuration config = parser->configuration();
-        config.preferredProjectPartId = projectPart->id();
-        config.editorDefines = defines;
-        parser->setConfiguration(config);
 
-        emit preprocessorSettingsChanged(!defines.trimmed().isEmpty());
+    CppTools::BaseEditorDocumentParser::Configuration config = parser->configuration();
+    if (config.editorDefines != directives) {
+        config.editorDefines = directives;
+        processor()->setParserConfig(config);
+
+        emit preprocessorSettingsChanged(!directives.trimmed().isEmpty());
+    }
+}
+
+void CppEditorDocument::setPreferredParseContext(const QString &parseContextId)
+{
+    const CppTools::BaseEditorDocumentParser::Ptr parser = processor()->parser();
+    QTC_ASSERT(parser, return);
+
+    CppTools::BaseEditorDocumentParser::Configuration config = parser->configuration();
+    if (config.preferredProjectPartId != parseContextId) {
+        config.preferredProjectPartId = parseContextId;
+        processor()->setParserConfig(config);
     }
 }
 
@@ -299,6 +337,23 @@ void CppEditorDocument::releaseResources()
     m_processor.reset();
 }
 
+void CppEditorDocument::showHideInfoBarAboutMultipleParseContexts(bool show)
+{
+    const Core::Id id = Constants::MULTIPLE_PARSE_CONTEXTS_AVAILABLE;
+
+    if (show) {
+        Core::InfoBarEntry info(id,
+                                tr("Note: Multiple parse contexts are available for this file. "
+                                   "Choose the preferred one from the editor toolbar."),
+                                Core::InfoBarEntry::GlobalSuppressionEnabled);
+        info.removeCancelButton();
+        if (infoBar()->canInfoBeAdded(id))
+            infoBar()->addInfo(info);
+    } else {
+        infoBar()->removeInfo(id);
+    }
+}
+
 void CppEditorDocument::initializeTimer()
 {
     m_processorTimer.setSingleShot(true);
@@ -311,6 +366,11 @@ void CppEditorDocument::initializeTimer()
             Qt::UniqueConnection);
 }
 
+ParseContextModel &CppEditorDocument::parseContextModel()
+{
+    return m_parseContextModel;
+}
+
 const MinimizableInfoBars &CppEditorDocument::minimizableInfoBars() const
 {
     return m_minimizableInfoBars;
@@ -321,11 +381,15 @@ CppTools::BaseEditorDocumentProcessor *CppEditorDocument::processor()
     if (!m_processor) {
         m_processor.reset(mm()->editorDocumentProcessor(this));
         connect(m_processor.data(), &CppTools::BaseEditorDocumentProcessor::projectPartInfoUpdated,
-                [this] (const CppTools::ProjectPartInfo &projectPartInfo)
+                [this] (const CppTools::ProjectPartInfo &info)
         {
-            const bool hasProjectPart
-                    = projectPartInfo.hint != CppTools::ProjectPartInfo::IsFallbackMatch;
+            using namespace CppTools;
+            const bool hasProjectPart = !(info.hints & ProjectPartInfo::IsFallbackMatch);
             m_minimizableInfoBars.processHasProjectPart(hasProjectPart);
+            m_parseContextModel.update(info);
+            const bool isAmbiguous = info.hints & ProjectPartInfo::IsAmbiguousMatch;
+            const bool isProjectFile = info.hints & ProjectPartInfo::IsFromProjectMatch;
+            showHideInfoBarAboutMultipleParseContexts(isAmbiguous && isProjectFile);
         });
         connect(m_processor.data(), &CppTools::BaseEditorDocumentProcessor::codeWarningsUpdated,
                 [this] (unsigned revision,
diff --git a/src/plugins/cppeditor/cppeditordocument.h b/src/plugins/cppeditor/cppeditordocument.h
index 9551ccf567c..89c97b42ab6 100644
--- a/src/plugins/cppeditor/cppeditordocument.h
+++ b/src/plugins/cppeditor/cppeditordocument.h
@@ -26,6 +26,7 @@
 #pragma once
 
 #include "cppminimizableinfobars.h"
+#include "cppparsecontext.h"
 
 #include <cpptools/baseeditordocumentprocessor.h>
 #include <cpptools/cppcompletionassistprovider.h>
@@ -57,11 +58,13 @@ public:
     void recalculateSemanticInfoDetached();
     CppTools::SemanticInfo recalculateSemanticInfo(); // TODO: Remove me
 
-    void setPreprocessorSettings(const CppTools::ProjectPart::Ptr &projectPart,
-                                 const QByteArray &defines);
+    void setPreferredParseContext(const QString &parseContextId);
+    void setExtraPreprocessorDirectives(const QByteArray &directives);
+
     void scheduleProcessDocument();
 
     const MinimizableInfoBars &minimizableInfoBars() const;
+    ParseContextModel &parseContextModel();
 
 signals:
     void codeWarningsUpdated(unsigned contentsRevision,
@@ -87,6 +90,8 @@ private:
     void onAboutToReload();
     void onReloadFinished();
 
+    void reparseWithPreferredParseContext(const QString &id);
+
     void processDocument();
 
     QByteArray contentsText() const;
@@ -94,9 +99,12 @@ private:
 
     CppTools::BaseEditorDocumentProcessor *processor();
     void resetProcessor();
-    void updatePreprocessorSettings();
+    void applyPreferredParseContextFromSettings();
+    void applyExtraPreprocessorDirectivesFromSettings();
     void releaseResources();
 
+    void showHideInfoBarAboutMultipleParseContexts(bool show);
+
     void initializeTimer();
 
 private:
@@ -118,6 +126,7 @@ private:
     QScopedPointer<CppTools::CppEditorDocumentHandle> m_editorDocumentHandle;
 
     MinimizableInfoBars m_minimizableInfoBars;
+    ParseContextModel m_parseContextModel;
 };
 
 } // namespace Internal
diff --git a/src/plugins/cppeditor/cppparsecontext.cpp b/src/plugins/cppeditor/cppparsecontext.cpp
new file mode 100644
index 00000000000..7be8b5beb10
--- /dev/null
+++ b/src/plugins/cppeditor/cppparsecontext.cpp
@@ -0,0 +1,172 @@
+/****************************************************************************
+**
+** Copyright (C) 2017 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of Qt Creator.
+**
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3 as published by the Free Software
+** Foundation with exceptions as appearing in the file LICENSE.GPL3-EXCEPT
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-3.0.html.
+**
+****************************************************************************/
+
+#include "cppparsecontext.h"
+
+#include <QAction>
+#include <QDir>
+#include <QDebug>
+
+#include <utils/algorithm.h>
+#include <utils/qtcassert.h>
+
+namespace CppEditor {
+namespace Internal {
+
+void ParseContextModel::update(const CppTools::ProjectPartInfo &projectPartInfo)
+{
+    beginResetModel();
+    reset(projectPartInfo);
+    endResetModel();
+
+    emit updated(areMultipleAvailable());
+}
+
+QString ParseContextModel::currentToolTip() const
+{
+    const QModelIndex index = createIndex(m_currentIndex, 0);
+    if (!index.isValid())
+        return QString();
+
+    return tr("<p><b>Active Parse Context</b>:<br/>%1</p>"
+              "<p>Multiple parse contexts (set of defines, include paths, and so on) "
+              "are available for this file.</p>"
+              "<p>Choose a parse context to set it as the preferred one. "
+              "Clear the preference from the context menu.</p>")
+                .arg(data(index, Qt::ToolTipRole).toString());
+}
+
+void ParseContextModel::setPreferred(int index)
+{
+    if (index < 0)
+        return;
+
+    emit preferredParseContextChanged(m_projectParts[index]->id());
+}
+
+void ParseContextModel::clearPreferred()
+{
+    emit preferredParseContextChanged(QString());
+}
+
+bool ParseContextModel::areMultipleAvailable() const
+{
+    return m_projectParts.size() >= 2;
+}
+
+void ParseContextModel::reset(const CppTools::ProjectPartInfo &projectPartInfo)
+{
+    // Sort
+    m_hints = projectPartInfo.hints;
+    m_projectParts = projectPartInfo.projectParts;
+    Utils::sort(m_projectParts, &CppTools::ProjectPart::displayName);
+
+    // Determine index for current
+    const QString id = projectPartInfo.projectPart->id();
+    m_currentIndex = Utils::indexOf(m_projectParts, [id](const CppTools::ProjectPart::Ptr &pp) {
+        return pp->id() == id;
+    });
+    QTC_CHECK(m_currentIndex >= 0);
+}
+
+int ParseContextModel::currentIndex() const
+{
+    return m_currentIndex;
+}
+
+bool ParseContextModel::isCurrentPreferred() const
+{
+    return m_hints & CppTools::ProjectPartInfo::IsPreferredMatch;
+}
+
+QString ParseContextModel::currentId() const
+{
+    if (m_currentIndex < 0)
+        return QString();
+
+    return m_projectParts[m_currentIndex]->id();
+}
+
+int ParseContextModel::rowCount(const QModelIndex &) const
+{
+    return m_projectParts.size();
+}
+
+QVariant ParseContextModel::data(const QModelIndex &index, int role) const
+{
+    if (m_projectParts.isEmpty())
+        return QVariant();
+
+    const int row = index.row();
+    if (role == Qt::DisplayRole)
+        return m_projectParts[row]->displayName;
+    else if (role == Qt::ToolTipRole)
+        return QDir::toNativeSeparators(m_projectParts[row]->projectFile);
+
+    return QVariant();
+}
+
+ParseContextWidget::ParseContextWidget(ParseContextModel &parseContextModel, QWidget *parent)
+    : QComboBox(parent)
+    , m_parseContextModel(parseContextModel)
+{
+    // Set up context menu with a clear action
+    setContextMenuPolicy(Qt::ActionsContextMenu);
+    m_clearPreferredAction = new QAction(tr("Clear Preferred Parse Context"), this);
+    connect(m_clearPreferredAction,  &QAction::triggered,[&]() {
+        m_parseContextModel.clearPreferred();
+    });
+    addAction(m_clearPreferredAction);
+
+    // Set up sync of this widget and model in both directions
+    connect(this,
+            static_cast<void (QComboBox::*)(int)>(&QComboBox::activated),
+            &m_parseContextModel,
+            &ParseContextModel::setPreferred);
+    connect(&m_parseContextModel, &ParseContextModel::updated,
+            this, &ParseContextWidget::syncToModel);
+
+    // Set up model
+    setModel(&m_parseContextModel);
+}
+
+void ParseContextWidget::syncToModel()
+{
+    const int index = m_parseContextModel.currentIndex();
+    if (index < 0)
+        return; // E.g. editor was duplicated but no project context was determined yet.
+
+    if (currentIndex() != index)
+        setCurrentIndex(index);
+
+    setToolTip(m_parseContextModel.currentToolTip());
+
+    const bool isPreferred = m_parseContextModel.isCurrentPreferred();
+    m_clearPreferredAction->setEnabled(isPreferred);
+    QComboBox::setProperty("highlightWidget", isPreferred);
+}
+
+} // namespace Internal
+} // namespace CppEditor
diff --git a/src/plugins/cppeditor/cppparsecontext.h b/src/plugins/cppeditor/cppparsecontext.h
new file mode 100644
index 00000000000..4c6cc95e9dc
--- /dev/null
+++ b/src/plugins/cppeditor/cppparsecontext.h
@@ -0,0 +1,83 @@
+/****************************************************************************
+**
+** Copyright (C) 2017 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of Qt Creator.
+**
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3 as published by the Free Software
+** Foundation with exceptions as appearing in the file LICENSE.GPL3-EXCEPT
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-3.0.html.
+**
+****************************************************************************/
+
+#pragma once
+
+#include <cpptools/cpptools_utils.h>
+
+#include <QAbstractListModel>
+#include <QComboBox>
+
+namespace CppEditor {
+namespace Internal {
+
+class ParseContextModel : public QAbstractListModel
+{
+    Q_OBJECT
+
+public:
+    void update(const CppTools::ProjectPartInfo &projectPartInfo);
+
+    void setPreferred(int index);
+    void clearPreferred();
+
+    int currentIndex() const;
+    bool isCurrentPreferred() const;
+
+    QString currentId() const;
+    QString currentToolTip() const;
+
+    bool areMultipleAvailable() const;
+
+signals:
+    void updated(bool areMultipleAvailable);
+    void preferredParseContextChanged(const QString &id);
+
+private:
+    void reset(const CppTools::ProjectPartInfo &projectPartInfo);
+    int rowCount(const QModelIndex &parent) const override;
+    QVariant data(const QModelIndex &index, int role) const override;
+
+private:
+    CppTools::ProjectPartInfo::Hints m_hints;
+    QList<CppTools::ProjectPart::Ptr> m_projectParts;
+    int m_currentIndex = -1;
+};
+
+class ParseContextWidget : public QComboBox
+{
+    Q_OBJECT
+
+public:
+    ParseContextWidget(ParseContextModel &parseContextModel, QWidget *parent);
+    void syncToModel();
+
+private:
+    ParseContextModel &m_parseContextModel;
+    QAction *m_clearPreferredAction = nullptr;
+};
+
+} // namespace Internal
+} // namespace CppEditor
diff --git a/src/plugins/cppeditor/cpppreprocessordialog.cpp b/src/plugins/cppeditor/cpppreprocessordialog.cpp
index 0e770405c6c..bbc7c49e4c6 100644
--- a/src/plugins/cppeditor/cpppreprocessordialog.cpp
+++ b/src/plugins/cppeditor/cpppreprocessordialog.cpp
@@ -31,18 +31,9 @@
 
 #include <projectexplorer/session.h>
 
-#include <algorithm>
-
 using namespace CppEditor::Internal;
 
-static bool projectPartLessThan(const CppTools::ProjectPart::Ptr &projectPart1,
-                                const CppTools::ProjectPart::Ptr &projectPart2)
-{
-    return projectPart1->displayName < projectPart2->displayName;
-}
-
-CppPreProcessorDialog::CppPreProcessorDialog(QWidget *parent, const QString &filePath,
-                                             const QList<CppTools::ProjectPart::Ptr> &projectParts)
+CppPreProcessorDialog::CppPreProcessorDialog(const QString &filePath, QWidget *parent)
     : QDialog(parent)
     , m_ui(new Ui::CppPreProcessorDialog())
     , m_filePath(filePath)
@@ -55,32 +46,9 @@ CppPreProcessorDialog::CppPreProcessorDialog(QWidget *parent, const QString &fil
 
     CppSnippetProvider().decorateEditor(m_ui->editWidget);
 
-    const QString &projectPartIdToUse = ProjectExplorer::SessionManager::value(
-                QLatin1String(Constants::CPP_PREPROCESSOR_PROJECT_PREFIX) + m_filePath).toString();
-    int currentIndex = 0;
-
-    QList<CppTools::ProjectPart::Ptr> sortedProjectParts(projectParts);
-    std::stable_sort(sortedProjectParts.begin(), sortedProjectParts.end(), projectPartLessThan);
-
-    foreach (CppTools::ProjectPart::Ptr projectPart, sortedProjectParts) {
-        m_ui->projectComboBox->addItem(projectPart->displayName);
-        ProjectPartAddition addition;
-        addition.projectPart = projectPart;
-        addition.additionalDirectives = ProjectExplorer::SessionManager::value(
-                    projectPart->id() + QLatin1Char(',') +  m_filePath).toString();
-        if (projectPart->id() == projectPartIdToUse)
-            currentIndex = m_ui->projectComboBox->count() - 1;
-        m_partAdditions << addition;
-    }
-    if (m_ui->projectComboBox->count() <= 1)
-        m_ui->projectComboBox->setEnabled(false);
-    m_ui->projectComboBox->setCurrentIndex(currentIndex);
-    m_ui->editWidget->setPlainText(m_partAdditions.value(currentIndex).additionalDirectives);
-
-    connect(m_ui->projectComboBox,
-            static_cast<void (QComboBox::*)(int)>(&QComboBox::currentIndexChanged),
-            this, &CppPreProcessorDialog::projectChanged);
-    connect(m_ui->editWidget, &QPlainTextEdit::textChanged, this, &CppPreProcessorDialog::textChanged);
+    const QString key = Constants::EXTRA_PREPROCESSOR_DIRECTIVES + m_filePath;
+    const QString directives = ProjectExplorer::SessionManager::value(key).toString();
+    m_ui->editWidget->setPlainText(directives);
 }
 
 CppPreProcessorDialog::~CppPreProcessorDialog()
@@ -93,41 +61,13 @@ int CppPreProcessorDialog::exec()
     if (QDialog::exec() == Rejected)
         return Rejected;
 
-    ProjectExplorer::SessionManager::setValue(
-                QLatin1String(Constants::CPP_PREPROCESSOR_PROJECT_PREFIX) + m_filePath,
-                m_partAdditions[m_ui->projectComboBox->currentIndex()].projectPart->id());
+    const QString key = Constants::EXTRA_PREPROCESSOR_DIRECTIVES + m_filePath;
+    ProjectExplorer::SessionManager::setValue(key, extraPreprocessorDirectives());
 
-    foreach (ProjectPartAddition partAddition, m_partAdditions) {
-        const QString &previousDirectives = ProjectExplorer::SessionManager::value(
-                    partAddition.projectPart->id()
-                    + QLatin1Char(',')
-                    + m_filePath).toString();
-        if (previousDirectives != partAddition.additionalDirectives) {
-            ProjectExplorer::SessionManager::setValue(
-                        partAddition.projectPart->id() + QLatin1Char(',') +  m_filePath,
-                        partAddition.additionalDirectives);
-        }
-    }
     return Accepted;
 }
 
-CppTools::ProjectPart::Ptr CppPreProcessorDialog::projectPart() const
-{
-    return m_partAdditions[m_ui->projectComboBox->currentIndex()].projectPart;
-}
-
-QString CppPreProcessorDialog::additionalPreProcessorDirectives() const
+QString CppPreProcessorDialog::extraPreprocessorDirectives() const
 {
     return m_ui->editWidget->toPlainText();
 }
-
-void CppPreProcessorDialog::projectChanged(int index)
-{
-    m_ui->editWidget->setPlainText(m_partAdditions[index].additionalDirectives);
-}
-
-void CppPreProcessorDialog::textChanged()
-{
-    m_partAdditions[m_ui->projectComboBox->currentIndex()].additionalDirectives
-            = m_ui->editWidget->toPlainText();
-}
diff --git a/src/plugins/cppeditor/cpppreprocessordialog.h b/src/plugins/cppeditor/cpppreprocessordialog.h
index 8a0c8865ac5..2bca50f4011 100644
--- a/src/plugins/cppeditor/cpppreprocessordialog.h
+++ b/src/plugins/cppeditor/cpppreprocessordialog.h
@@ -25,9 +25,8 @@
 
 #pragma once
 
-#include <cpptools/cppmodelmanager.h>
-
 #include <QDialog>
+#include <QString>
 
 namespace CppEditor {
 namespace Internal {
@@ -38,27 +37,17 @@ class CppPreProcessorDialog : public QDialog
     Q_OBJECT
 
 public:
-    explicit CppPreProcessorDialog(QWidget *parent, const QString &filePath,
-                                   const QList<CppTools::ProjectPart::Ptr> &projectParts);
+    explicit CppPreProcessorDialog(const QString &filePath, QWidget *parent);
     ~CppPreProcessorDialog();
 
     int exec();
 
-    CppTools::ProjectPart::Ptr projectPart() const;
-    QString additionalPreProcessorDirectives() const;
+    QString extraPreprocessorDirectives() const;
 
 private:
-    void projectChanged(int index);
-    void textChanged();
-
-    struct ProjectPartAddition {
-        CppTools::ProjectPart::Ptr projectPart;
-        QString additionalDirectives;
-    };
-
     Ui::CppPreProcessorDialog *m_ui;
-    QList<ProjectPartAddition> m_partAdditions;
-    QString m_filePath;
+    const QString m_filePath;
+    const QString m_projectPartId;
 };
 
 } // namespace Internal
diff --git a/src/plugins/cppeditor/cpppreprocessordialog.ui b/src/plugins/cppeditor/cpppreprocessordialog.ui
index 38609011565..4dbcd968b8c 100644
--- a/src/plugins/cppeditor/cpppreprocessordialog.ui
+++ b/src/plugins/cppeditor/cpppreprocessordialog.ui
@@ -14,34 +14,6 @@
    <string>Additional C++ Preprocessor Directives</string>
   </property>
   <layout class="QVBoxLayout" name="verticalLayout">
-   <item>
-    <layout class="QHBoxLayout" name="horizontalLayout">
-     <item>
-      <widget class="QLabel" name="projectLabel">
-       <property name="text">
-        <string>Project:</string>
-       </property>
-      </widget>
-     </item>
-     <item>
-      <widget class="QComboBox" name="projectComboBox">
-       <property name="sizePolicy">
-        <sizepolicy hsizetype="Expanding" vsizetype="Fixed">
-         <horstretch>0</horstretch>
-         <verstretch>0</verstretch>
-        </sizepolicy>
-       </property>
-      </widget>
-     </item>
-    </layout>
-   </item>
-   <item>
-    <widget class="Line" name="separator">
-     <property name="orientation">
-      <enum>Qt::Horizontal</enum>
-     </property>
-    </widget>
-   </item>
    <item>
     <widget class="QLabel" name="editorLabel">
      <property name="text">
diff --git a/src/plugins/cpptools/baseeditordocumentprocessor.cpp b/src/plugins/cpptools/baseeditordocumentprocessor.cpp
index ad26fa653c3..2bf77787d76 100644
--- a/src/plugins/cpptools/baseeditordocumentprocessor.cpp
+++ b/src/plugins/cpptools/baseeditordocumentprocessor.cpp
@@ -87,6 +87,12 @@ void BaseEditorDocumentProcessor::editorDocumentTimerRestarted()
 {
 }
 
+void BaseEditorDocumentProcessor::setParserConfig(
+        const BaseEditorDocumentParser::Configuration config)
+{
+    parser()->setConfiguration(config);
+}
+
 void BaseEditorDocumentProcessor::runParser(QFutureInterface<void> &future,
                                             BaseEditorDocumentParser::Ptr parser,
                                             BaseEditorDocumentParser::UpdateParams updateParams)
diff --git a/src/plugins/cpptools/baseeditordocumentprocessor.h b/src/plugins/cpptools/baseeditordocumentprocessor.h
index 2f2fdc3af20..155edac6750 100644
--- a/src/plugins/cpptools/baseeditordocumentprocessor.h
+++ b/src/plugins/cpptools/baseeditordocumentprocessor.h
@@ -70,6 +70,8 @@ public:
 
     virtual void editorDocumentTimerRestarted();
 
+    virtual void setParserConfig(const BaseEditorDocumentParser::Configuration config);
+
 public:
     using HeaderErrorDiagnosticWidgetCreator = std::function<QWidget*()>;
 
diff --git a/src/plugins/cpptools/cppprojectpartchooser.cpp b/src/plugins/cpptools/cppprojectpartchooser.cpp
index a79b44540a7..bbf9ca35594 100644
--- a/src/plugins/cpptools/cppprojectpartchooser.cpp
+++ b/src/plugins/cpptools/cppprojectpartchooser.cpp
@@ -37,7 +37,7 @@ public:
     struct PrioritizedProjectPart
     {
         PrioritizedProjectPart(const ProjectPart::Ptr &projectPart, int priority)
-            : projectPart(projectPart) , priority(priority) {}
+            : projectPart(projectPart), priority(priority) {}
 
         ProjectPart::Ptr projectPart;
         int priority = 0;
@@ -46,38 +46,42 @@ public:
     ProjectPartPrioritizer(const QList<ProjectPart::Ptr> &projectParts,
                            const QString &preferredProjectPartId,
                            const ProjectExplorer::Project *activeProject,
-                           Language languagePreference)
-        : m_projectParts(projectParts)
-        , m_preferredProjectPartId(preferredProjectPartId)
+                           Language languagePreference,
+                           bool areProjectPartsFromDependencies)
+        : m_preferredProjectPartId(preferredProjectPartId)
         , m_activeProject(activeProject)
         , m_languagePreference(languagePreference)
     {
-        // Determine best project part
-        const QList<PrioritizedProjectPart> prioritized = prioritize();
-        m_projectPart = prioritized.first().projectPart;
+        // Prioritize
+        const QList<PrioritizedProjectPart> prioritized = prioritize(projectParts);
+        for (const PrioritizedProjectPart &ppp : prioritized)
+            m_info.projectParts << ppp.projectPart;
 
-        // Determine ambiguity
-        m_isAmbiguous = prioritized.size() > 1
-                ? prioritized[0].priority == prioritized[1].priority
-                : false;
+        // Best project part
+        m_info.projectPart = m_info.projectParts.first();
+
+        // Hints
+        if (m_info.projectParts.size() > 1)
+            m_info.hints |= ProjectPartInfo::IsAmbiguousMatch;
+        if (prioritized.first().priority > 1000)
+            m_info.hints |= ProjectPartInfo::IsPreferredMatch;
+        if (areProjectPartsFromDependencies)
+            m_info.hints |= ProjectPartInfo::IsFromDependenciesMatch;
+        else
+            m_info.hints |= ProjectPartInfo::IsFromProjectMatch;
     }
 
-    ProjectPart::Ptr projectPart()
+    ProjectPartInfo info() const
     {
-        return m_projectPart;
-    }
-
-    bool isAmbiguous() const
-    {
-        return m_isAmbiguous;
+        return m_info;
     }
 
 private:
-    QList<PrioritizedProjectPart> prioritize()
+    QList<PrioritizedProjectPart> prioritize(const QList<ProjectPart::Ptr> &projectParts)
     {
         // Prioritize
-        QList<PrioritizedProjectPart> prioritized = Utils::transform(m_projectParts,
-                [&](const ProjectPart::Ptr &projectPart) {
+        QList<PrioritizedProjectPart> prioritized = Utils::transform(projectParts,
+                                                        [&](const ProjectPart::Ptr &projectPart) {
             return PrioritizedProjectPart{projectPart, priority(*projectPart)};
         });
 
@@ -118,14 +122,12 @@ private:
     }
 
 private:
-    const QList<ProjectPart::Ptr> m_projectParts;
     const QString m_preferredProjectPartId;
     const ProjectExplorer::Project *m_activeProject = nullptr;
     Language m_languagePreference = Language::Cxx;
 
     // Results
-    ProjectPart::Ptr m_projectPart;
-    bool m_isAmbiguous = false;
+    ProjectPartInfo m_info;
 };
 
 ProjectPartInfo ProjectPartChooser::choose(
@@ -141,40 +143,30 @@ ProjectPartInfo ProjectPartChooser::choose(
     QTC_CHECK(m_fallbackProjectPart);
 
     ProjectPart::Ptr projectPart = currentProjectPartInfo.projectPart;
-    ProjectPartInfo::Hint hint = ProjectPartInfo::NoHint;
-
     QList<ProjectPart::Ptr> projectParts = m_projectPartsForFile(filePath);
+    bool areProjectPartsFromDependencies = false;
+
     if (projectParts.isEmpty()) {
         if (!projectsUpdated && projectPart
-                && currentProjectPartInfo.hint == ProjectPartInfo::IsFallbackMatch)
+                && currentProjectPartInfo.hints & ProjectPartInfo::IsFallbackMatch)
             // Avoid re-calculating the expensive dependency table for non-project files.
-            return {projectPart, ProjectPartInfo::IsFallbackMatch};
+            return ProjectPartInfo(projectPart, {projectPart}, ProjectPartInfo::IsFallbackMatch);
 
         // Fall-back step 1: Get some parts through the dependency table:
         projectParts = m_projectPartsFromDependenciesForFile(filePath);
         if (projectParts.isEmpty()) {
             // Fall-back step 2: Use fall-back part from the model manager:
             projectPart = m_fallbackProjectPart();
-            hint = ProjectPartInfo::IsFallbackMatch;
-        } else {
-            ProjectPartPrioritizer prioritizer(projectParts,
-                                               preferredProjectPartId,
-                                               activeProject,
-                                               languagePreference);
-            projectPart = prioritizer.projectPart();
+            return ProjectPartInfo(projectPart, {projectPart}, ProjectPartInfo::IsFallbackMatch);
         }
-    } else {
-        ProjectPartPrioritizer prioritizer(projectParts,
-                                           preferredProjectPartId,
-                                           activeProject,
-                                           languagePreference);
-        projectPart = prioritizer.projectPart();
-        hint = prioritizer.isAmbiguous()
-                ? ProjectPartInfo::IsAmbiguousMatch
-                : ProjectPartInfo::NoHint;
+        areProjectPartsFromDependencies = true;
     }
 
-    return {projectPart, hint};
+    return ProjectPartPrioritizer(projectParts,
+                                  preferredProjectPartId,
+                                  activeProject,
+                                  languagePreference,
+                                  areProjectPartsFromDependencies).info();
 }
 
 void ProjectPartChooser::setFallbackProjectPart(const FallBackProjectPart &getter)
diff --git a/src/plugins/cpptools/cpptools_utils.h b/src/plugins/cpptools/cpptools_utils.h
index a90805a7ab0..7c775998d6d 100644
--- a/src/plugins/cpptools/cpptools_utils.h
+++ b/src/plugins/cpptools/cpptools_utils.h
@@ -34,14 +34,29 @@ enum class Language { C, Cxx };
 class ProjectPartInfo {
 public:
     enum Hint {
-        NoHint,
-        IsFallbackMatch,
-        IsAmbiguousMatch
+        NoHint = 0,
+        IsFallbackMatch  = 1 << 0,
+        IsAmbiguousMatch = 1 << 1,
+        IsPreferredMatch = 1 << 2,
+        IsFromProjectMatch = 1 << 3,
+        IsFromDependenciesMatch = 1 << 4,
     };
+    Q_DECLARE_FLAGS(Hints, Hint)
+
+    ProjectPartInfo() = default;
+    ProjectPartInfo(const ProjectPart::Ptr &projectPart,
+                    const QList<ProjectPart::Ptr> &projectParts,
+                    Hints hints)
+        : projectPart(projectPart)
+        , projectParts(projectParts)
+        , hints(hints)
+    {
+    }
 
 public:
     ProjectPart::Ptr projectPart;
-    Hint hint;
+    QList<ProjectPart::Ptr> projectParts; // The one above as first plus alternatives.
+    Hints hints = NoHint;
 };
 
 } // namespace CppTools
diff --git a/tests/unit/unittest/cppprojectpartchooser-test.cpp b/tests/unit/unittest/cppprojectpartchooser-test.cpp
index b2f3918cbc2..8020d1a35cc 100644
--- a/tests/unit/unittest/cppprojectpartchooser-test.cpp
+++ b/tests/unit/unittest/cppprojectpartchooser-test.cpp
@@ -49,7 +49,9 @@ protected:
 
 protected:
     QString filePath;
-    ProjectPartInfo currentProjectPartInfo{ProjectPart::Ptr(new ProjectPart),
+    ProjectPart::Ptr currentProjectPart{new ProjectPart};
+    ProjectPartInfo currentProjectPartInfo{currentProjectPart,
+                                           {currentProjectPart},
                                            ProjectPartInfo::NoHint};
     QString preferredProjectPartId;
     const ProjectExplorer::Project *activeProject = nullptr;
@@ -74,6 +76,37 @@ TEST_F(ProjectPartChooser, ChooseManuallySet)
     ASSERT_THAT(chosen, Eq(p2));
 }
 
+TEST_F(ProjectPartChooser, IndicateManuallySet)
+{
+    ProjectPart::Ptr p1(new ProjectPart);
+    ProjectPart::Ptr p2(new ProjectPart);
+    p2->projectFile = preferredProjectPartId = "someId";
+    projectPartsForFile += {p1, p2};
+
+    const ProjectPartInfo::Hints hints = choose().hints;
+
+    ASSERT_TRUE(hints & ProjectPartInfo::IsPreferredMatch);
+}
+
+TEST_F(ProjectPartChooser, IndicateManuallySetForFallbackToProjectPartFromDependencies)
+{
+    ProjectPart::Ptr p1(new ProjectPart);
+    ProjectPart::Ptr p2(new ProjectPart);
+    p2->projectFile = preferredProjectPartId = "someId";
+    projectPartsFromDependenciesForFile += {p1, p2};
+
+    const ProjectPartInfo::Hints hints = choose().hints;
+
+    ASSERT_TRUE(hints & ProjectPartInfo::IsPreferredMatch);
+}
+
+TEST_F(ProjectPartChooser, DoNotIndicateNotManuallySet)
+{
+    const ProjectPartInfo::Hints hints = choose().hints;
+
+    ASSERT_FALSE(hints & ProjectPartInfo::IsPreferredMatch);
+}
+
 TEST_F(ProjectPartChooser, ForMultipleChooseFromActiveProject)
 {
     const QList<ProjectPart::Ptr> projectParts = createProjectPartsWithDifferentProjects();
@@ -154,9 +187,20 @@ TEST_F(ProjectPartChooser, IndicateMultiple)
     const ProjectPart::Ptr p2{new ProjectPart};
     projectPartsForFile += { p1, p2 };
 
-    const ProjectPartInfo::Hint hint = choose().hint;
+    const ProjectPartInfo::Hints hints = choose().hints;
 
-    ASSERT_THAT(hint, Eq(ProjectPartInfo::Hint::IsAmbiguousMatch));
+    ASSERT_TRUE(hints & ProjectPartInfo::IsAmbiguousMatch);
+}
+
+TEST_F(ProjectPartChooser, IndicateMultipleForFallbackToProjectPartFromDependencies)
+{
+    const ProjectPart::Ptr p1{new ProjectPart};
+    const ProjectPart::Ptr p2{new ProjectPart};
+    projectPartsFromDependenciesForFile += { p1, p2 };
+
+    const ProjectPartInfo::Hints hints = choose().hints;
+
+    ASSERT_TRUE(hints & ProjectPartInfo::IsAmbiguousMatch);
 }
 
 TEST_F(ProjectPartChooser, ForMultipleChooseNewIfPreviousIsGone)
@@ -193,7 +237,7 @@ TEST_F(ProjectPartChooser, ContinueUsingFallbackFromModelManagerIfProjectDoesNot
     // ...without re-calculating the dependency table.
     fallbackProjectPart.reset(new ProjectPart);
     currentProjectPartInfo.projectPart = fallbackProjectPart;
-    currentProjectPartInfo.hint = ProjectPartInfo::IsFallbackMatch;
+    currentProjectPartInfo.hints |= ProjectPartInfo::IsFallbackMatch;
     projectPartsFromDependenciesForFile += ProjectPart::Ptr(new ProjectPart);
 
     const ProjectPart::Ptr chosen = choose().projectPart;
@@ -205,7 +249,7 @@ TEST_F(ProjectPartChooser, StopUsingFallbackFromModelManagerIfProjectChanges1)
 {
     fallbackProjectPart.reset(new ProjectPart);
     currentProjectPartInfo.projectPart = fallbackProjectPart;
-    currentProjectPartInfo.hint = ProjectPartInfo::IsFallbackMatch;
+    currentProjectPartInfo.hints |= ProjectPartInfo::IsFallbackMatch;
     const ProjectPart::Ptr addedProject(new ProjectPart);
     projectPartsForFile += addedProject;
 
@@ -218,7 +262,7 @@ TEST_F(ProjectPartChooser, StopUsingFallbackFromModelManagerIfProjectChanges2)
 {
     fallbackProjectPart.reset(new ProjectPart);
     currentProjectPartInfo.projectPart = fallbackProjectPart;
-    currentProjectPartInfo.hint = ProjectPartInfo::IsFallbackMatch;
+    currentProjectPartInfo.hints |= ProjectPartInfo::IsFallbackMatch;
     const ProjectPart::Ptr addedProject(new ProjectPart);
     projectPartsFromDependenciesForFile += addedProject;
     projectsChanged = true;
@@ -232,9 +276,27 @@ TEST_F(ProjectPartChooser, IndicateFallbacktoProjectPartFromModelManager)
 {
     fallbackProjectPart.reset(new ProjectPart);
 
-    const ProjectPartInfo::Hint hint = choose().hint;
+    const ProjectPartInfo::Hints hints = choose().hints;
 
-    ASSERT_THAT(hint, Eq(ProjectPartInfo::Hint::IsFallbackMatch));
+    ASSERT_TRUE(hints & ProjectPartInfo::IsFallbackMatch);
+}
+
+TEST_F(ProjectPartChooser, IndicateFromDependencies)
+{
+    projectPartsFromDependenciesForFile += ProjectPart::Ptr(new ProjectPart);
+
+    const ProjectPartInfo::Hints hints = choose().hints;
+
+    ASSERT_TRUE(hints & ProjectPartInfo::IsFromDependenciesMatch);
+}
+
+TEST_F(ProjectPartChooser, DoNotIndicateFromDependencies)
+{
+    projectPartsForFile += ProjectPart::Ptr(new ProjectPart);
+
+    const ProjectPartInfo::Hints hints = choose().hints;
+
+    ASSERT_FALSE(hints & ProjectPartInfo::IsFromDependenciesMatch);
 }
 
 void ProjectPartChooser::SetUp()