diff --git a/Triangulation_3/include/CGAL/Triangulation_3.h b/Triangulation_3/include/CGAL/Triangulation_3.h
index 4e4c5606545..29df6c203ce 100644
--- a/Triangulation_3/include/CGAL/Triangulation_3.h
+++ b/Triangulation_3/include/CGAL/Triangulation_3.h
@@ -447,7 +447,8 @@ private:
     const Self *t;
 
   public:
-    Infinite_tester() {}
+    Infinite_tester()
+      : t(nullptr) {}
 
     Infinite_tester(const Self *tr)
       : t(tr) {}