diff --git a/gdk/wayland/gdksubsurface-wayland.c b/gdk/wayland/gdksubsurface-wayland.c
index 5ee3ef9a51..ddae752a0d 100644
--- a/gdk/wayland/gdksubsurface-wayland.c
+++ b/gdk/wayland/gdksubsurface-wayland.c
@@ -253,6 +253,15 @@ wl_output_transform_to_gdk (enum wl_output_transform transform)
   return (GdkDihedral) transform;
 }
 
+G_STATIC_ASSERT ((int) WL_OUTPUT_TRANSFORM_NORMAL == (int) GDK_DIHEDRAL_NORMAL);
+G_STATIC_ASSERT ((int) WL_OUTPUT_TRANSFORM_90 == (int) GDK_DIHEDRAL_90);
+G_STATIC_ASSERT ((int) WL_OUTPUT_TRANSFORM_180 == (int) GDK_DIHEDRAL_180);
+G_STATIC_ASSERT ((int) WL_OUTPUT_TRANSFORM_270 == (int) GDK_DIHEDRAL_270);
+G_STATIC_ASSERT ((int) WL_OUTPUT_TRANSFORM_FLIPPED == (int) GDK_DIHEDRAL_FLIPPED);
+G_STATIC_ASSERT ((int) WL_OUTPUT_TRANSFORM_FLIPPED_90 == (int) GDK_DIHEDRAL_FLIPPED_90);
+G_STATIC_ASSERT ((int) WL_OUTPUT_TRANSFORM_FLIPPED_180 == (int) GDK_DIHEDRAL_FLIPPED_180);
+G_STATIC_ASSERT ((int) WL_OUTPUT_TRANSFORM_FLIPPED_270 == (int) GDK_DIHEDRAL_FLIPPED_270);
+
 static void
 ensure_bg_surface (GdkWaylandSubsurface *self)
 {