diff --git a/src/libslic3r/SLA/SLAAutoSupports.hpp b/src/libslic3r/SLA/SLAAutoSupports.hpp
index b552d1c0ba..0d5cc64f17 100644
--- a/src/libslic3r/SLA/SLAAutoSupports.hpp
+++ b/src/libslic3r/SLA/SLAAutoSupports.hpp
@@ -1,6 +1,7 @@
 #ifndef SLAAUTOSUPPORTS_HPP_
 #define SLAAUTOSUPPORTS_HPP_
 
+#include <libslic3r/ClipperUtils.hpp>
 #include <libslic3r/Point.hpp>
 #include <libslic3r/TriangleMesh.hpp>
 #include <libslic3r/SLA/SLACommon.hpp>