1 files changed, 1 insertions, 1 deletions
diff --git a/include/vcl/dockwin.hxx b/include/vcl/dockwin.hxx
index b2808f043dfc..a3743c2f2c39 100644
--- a/include/vcl/dockwin.hxx
+++ b/include/vcl/dockwin.hxx
@@ -208,7 +208,7 @@ class VCL_DLLPUBLIC DockingWindow
     : public vcl::Window
     , public VclBuilderContainer
 {
-    class   ImplData;
+    class SAL_DLLPRIVATE ImplData;
 private:
     VclPtr<FloatingWindow> mpFloatWin;
     VclPtr<vcl::Window>    mpOldBorderWin;