diff --git a/components/detournavigator/findsmoothpath.hpp b/components/detournavigator/findsmoothpath.hpp
index 2fc39d63fb..dcdddce8a6 100644
--- a/components/detournavigator/findsmoothpath.hpp
+++ b/components/detournavigator/findsmoothpath.hpp
@@ -19,7 +19,7 @@
 #include <components/misc/convert.hpp>
 
 #include <osg/Vec3f>
-
+#include <cassert>
 #include <vector>
 
 class dtNavMesh;