diff --git a/src/plugins/cpptools/cppmodelmanager.cpp b/src/plugins/cpptools/cppmodelmanager.cpp
index a07bf91238a..2fb94adea90 100644
--- a/src/plugins/cpptools/cppmodelmanager.cpp
+++ b/src/plugins/cpptools/cppmodelmanager.cpp
@@ -629,21 +629,9 @@ public:
         , m_newSourceFiles(newProjectInfo.sourceFiles())
     {}
 
-    bool definesChanged() const
-    {
-        return m_new.defines() != m_old.defines();
-    }
-
-    bool configurationChanged() const
-    {
-        return definesChanged()
-            || m_new.headerPaths() != m_old.headerPaths();
-    }
-
-    bool nothingChanged() const
-    {
-        return !configurationChanged() && m_new.sourceFiles() == m_old.sourceFiles();
-    }
+    bool definesChanged() const { return m_new.definesChanged(m_old); }
+    bool configurationChanged() const { return m_new.configurationChanged(m_old); }
+    bool configurationOrFilesChanged() const { return m_new.configurationOrFilesChanged(m_old); }
 
     QSet<QString> addedFiles() const
     {
@@ -735,8 +723,12 @@ QFuture<void> CppModelManager::updateProjectInfo(const ProjectInfo &newProjectIn
         ProjectInfo oldProjectInfo = d->m_projectToProjectsInfo.value(project);
         if (oldProjectInfo.isValid()) {
             ProjectInfoComparer comparer(oldProjectInfo, newProjectInfo);
-            if (comparer.nothingChanged())
+
+            if (!comparer.configurationOrFilesChanged()) {
+                // Some other attached data might have changed
+                d->m_projectToProjectsInfo.insert(project, newProjectInfo);
                 return QFuture<void>();
+            }
 
             // If the project configuration changed, do a full reindexing
             if (comparer.configurationChanged()) {
diff --git a/src/plugins/cpptools/cppprojects.cpp b/src/plugins/cpptools/cppprojects.cpp
index 4aab008f28c..710a387f3a4 100644
--- a/src/plugins/cpptools/cppprojects.cpp
+++ b/src/plugins/cpptools/cppprojects.cpp
@@ -137,6 +137,36 @@ ProjectInfo::ProjectInfo(QPointer<ProjectExplorer::Project> project)
     : m_project(project)
 {}
 
+bool ProjectInfo::operator ==(const ProjectInfo &other) const
+{
+    return m_project == other.m_project
+            && m_projectParts == other.m_projectParts
+            && m_compilerCallData == other.m_compilerCallData
+            && m_headerPaths == other.m_headerPaths
+            && m_sourceFiles == other.m_sourceFiles
+            && m_defines == other.m_defines;
+}
+
+bool ProjectInfo::operator !=(const ProjectInfo &other) const
+{
+    return !operator ==(other);
+}
+
+bool ProjectInfo::definesChanged(const ProjectInfo &other) const
+{
+    return m_defines != other.m_defines;
+}
+
+bool ProjectInfo::configurationChanged(const ProjectInfo &other) const
+{
+    return definesChanged(other) || m_headerPaths != other.m_headerPaths;
+}
+
+bool ProjectInfo::configurationOrFilesChanged(const ProjectInfo &other) const
+{
+    return configurationChanged(other) || m_sourceFiles != other.m_sourceFiles;
+}
+
 bool ProjectInfo::isValid() const
 {
     return !m_project.isNull();
@@ -193,6 +223,7 @@ void ProjectInfo::clearProjectParts()
     m_headerPaths.clear();
     m_sourceFiles.clear();
     m_defines.clear();
+    m_compilerCallData.clear();
 }
 
 const ProjectPart::HeaderPaths ProjectInfo::headerPaths() const
@@ -210,6 +241,16 @@ const QByteArray ProjectInfo::defines() const
     return m_defines;
 }
 
+void ProjectInfo::setCompilerCallData(const CompilerCallData &data)
+{
+    m_compilerCallData = data;
+}
+
+ProjectInfo::CompilerCallData ProjectInfo::compilerCallData() const
+{
+    return m_compilerCallData;
+}
+
 namespace {
 class ProjectFileCategorizer
 {
diff --git a/src/plugins/cpptools/cppprojects.h b/src/plugins/cpptools/cppprojects.h
index 5277a0a9dac..b1ef7553112 100644
--- a/src/plugins/cpptools/cppprojects.h
+++ b/src/plugins/cpptools/cppprojects.h
@@ -142,6 +142,12 @@ public:
 
     bool isValid() const;
 
+    bool operator ==(const ProjectInfo &other) const;
+    bool operator !=(const ProjectInfo &other) const;
+    bool definesChanged(const ProjectInfo &other) const;
+    bool configurationChanged(const ProjectInfo &other) const;
+    bool configurationOrFilesChanged(const ProjectInfo &other) const;
+
     QPointer<ProjectExplorer::Project> project() const;
     const QList<ProjectPart::Ptr> projectParts() const;
 
@@ -153,10 +159,16 @@ public:
     const QSet<QString> sourceFiles() const;
     const QByteArray defines() const;
 
+    // Source file --> List of compiler calls
+    typedef QHash<QString, QList<QStringList>> CompilerCallData;
+    void setCompilerCallData(const CompilerCallData &data);
+    CompilerCallData compilerCallData() const;
+
 private:
     QPointer<ProjectExplorer::Project> m_project;
     QList<ProjectPart::Ptr> m_projectParts;
-    // The members below are (re)calculated from the project parts once a part is appended.
+    CompilerCallData m_compilerCallData;
+    // The members below are (re)calculated from the project parts with finish()
     ProjectPart::HeaderPaths m_headerPaths;
     QSet<QString> m_sourceFiles;
     QByteArray m_defines;