diff --git a/STL_Extension/include/CGAL/assertions.h b/STL_Extension/include/CGAL/assertions.h
index 08ca01e3e9e..777b61fdcb3 100644
--- a/STL_Extension/include/CGAL/assertions.h
+++ b/STL_Extension/include/CGAL/assertions.h
@@ -100,7 +100,7 @@ inline bool possibly(Uncertain<bool> c);
 #else // no CGAL_NO_ASSERTIONS
 #  define CGAL_assertion(EX) \
    (CGAL::possibly(EX)?(static_cast<void>(0)): ::CGAL::assertion_fail( # EX , __FILE__, __LINE__))
-#  if defined( __cpp_lib_uncaught_exceptions) || _MSVC_LANG >= 201103L // C++17
+#  if __cpp_lib_uncaught_exceptions || ( _MSVC_LANG >= 201103L )  // C++17
 #    define CGAL_destructor_assertion(EX) \
      (CGAL::possibly(EX)||(std::uncaught_exceptions() > 0)?(static_cast<void>(0)): ::CGAL::assertion_fail( # EX , __FILE__, __LINE__))
 #  else // use C++03 `std::uncaught_exception()`