diff --git a/src/plugins/cmakeprojectmanager/cmakeproject.h b/src/plugins/cmakeprojectmanager/cmakeproject.h
index 3ff9303936b..ce7d6a13682 100644
--- a/src/plugins/cmakeprojectmanager/cmakeproject.h
+++ b/src/plugins/cmakeprojectmanager/cmakeproject.h
@@ -31,10 +31,7 @@
 
 namespace CMakeProjectManager {
 
-namespace Internal {
-class CMakeProjectImporter;
-class CMakeBuildSystem;
-}
+namespace Internal { class CMakeProjectImporter; }
 
 class CMAKE_EXPORT CMakeProject final : public ProjectExplorer::Project
 {
@@ -62,8 +59,6 @@ private:
 
     mutable Internal::CMakeProjectImporter *m_projectImporter = nullptr;
 
-    friend class Internal::CMakeBuildSystem;
-
     ProjectExplorer::Tasks m_issues;
 };