diff --git a/xs/xsp/Polygon.xsp b/xs/xsp/Polygon.xsp
index 11fd04360..f63fc521b 100644
--- a/xs/xsp/Polygon.xsp
+++ b/xs/xsp/Polygon.xsp
@@ -3,6 +3,7 @@
 %{
 #include <myinit.h>
 #include "Polygon.hpp"
+#include "BoundingBox.hpp"
 %}
 
 %name{Slic3r::Polygon} class Polygon {