diff --git a/Polyhedron/demo/Polyhedron/CMakeLists.txt b/Polyhedron/demo/Polyhedron/CMakeLists.txt
index 35a493b5d68..609154cf40e 100644
--- a/Polyhedron/demo/Polyhedron/CMakeLists.txt
+++ b/Polyhedron/demo/Polyhedron/CMakeLists.txt
@@ -151,7 +151,8 @@ if(CGAL_Qt5_FOUND AND Qt5_FOUND AND OPENGL_FOUND AND QGLVIEWER_FOUND)
 
   add_library(demo_framework SHARED
     Scene.cpp
-    Viewer.cpp #Viewer_moc.cpp Viewer_interface_moc.cpp
+    Viewer.cpp #Viewer_moc.cpp
+    Viewer_interface_moc.cpp
     Scene_item.cpp #Scene_item.moc
     Scene_item_with_display_list.cpp
     Polyhedron_demo_plugin_helper.cpp)