diff --git a/STL_Extension/include/CGAL/assertions.h b/STL_Extension/include/CGAL/assertions.h
index 6c58383474f..b9e145ec9e7 100644
--- a/STL_Extension/include/CGAL/assertions.h
+++ b/STL_Extension/include/CGAL/assertions.h
@@ -63,7 +63,7 @@ inline void set_use_assertions(bool b)
 
 namespace CGAL{
 inline void set_use_assertions(bool){}
-inline bool get_use_assertions(){return true;}
+inline constexpr bool get_use_assertions(){return true;}
 }
 
 #endif