diff --git a/samples/widgets/native.cpp b/samples/widgets/native.cpp
index e9234fe480..030b8f8c40 100644
--- a/samples/widgets/native.cpp
+++ b/samples/widgets/native.cpp
@@ -67,6 +67,20 @@ void BuildTestMenu(wxMenu *menu)
     #define BS_SPLITBUTTON 0x000c
 #endif // BS_SPLITBUTTON
 
+#ifndef BCN_DROPDOWN
+    #define BCN_DROPDOWN (-1248)
+#endif // defined(BCN_DROPDOWN)
+
+// This duplicates the standard NMBCDROPDOWN struct which is not defined in
+// some old (up to at least 4.9.1) MinGW-w64 headers even though, annoyingly,
+// BCN_DROPDOWN is, so we can't even use as an indicator of whether the struct
+// is defined or not.
+struct wxNMBCDROPDOWN
+{
+    NMHDR hdr;
+    RECT rcButton;
+};
+
 class NativeWindow : public wxNativeWindow
 {
 public:
@@ -106,9 +120,6 @@ public:
     }
 
 protected:
-    // This code requires NMBCDROPDOWN to work, we don't really want to
-    // reproduce its definition here for very old compilers not having it.
-#ifdef BCN_DROPDOWN
     // Split buttons under MSW don't show the menu on their own, unlike their
     // equivalents under the other platforms, so do it manually here. This also
     // shows how to handle a native event in MSW (for the specific case of
@@ -120,7 +131,7 @@ protected:
         if ( hdr->code != BCN_DROPDOWN )
             return wxNativeWindow::MSWOnNotify(idCtrl, lParam, result);
 
-        const NMBCDROPDOWN* dd = reinterpret_cast<NMBCDROPDOWN*>(lParam);
+        const wxNMBCDROPDOWN* dd = reinterpret_cast<wxNMBCDROPDOWN*>(lParam);
 
         wxMenu menu;
         BuildTestMenu(&menu);
@@ -128,7 +139,6 @@ protected:
 
         return true;
     }
-#endif // defined(BCN_DROPDOWN)
 };
 
 #elif defined(__WXGTK__)