diff --git a/Constrained_triangulation_3/include/CGAL/Constrained_triangulation_3/internal/config.h b/Constrained_triangulation_3/include/CGAL/Constrained_triangulation_3/internal/config.h
index 99c39f2555b..47f53d42ac5 100644
--- a/Constrained_triangulation_3/include/CGAL/Constrained_triangulation_3/internal/config.h
+++ b/Constrained_triangulation_3/include/CGAL/Constrained_triangulation_3/internal/config.h
@@ -48,7 +48,7 @@ decltype(auto) cdt_3_format(std::string_view fmt, const Args&... args) {
 
 template <typename... Args>
 constexpr decltype(auto) cdt_3_format(Args&&...) {
-  return "";
+  return std::string{};
 }
 
 constexpr bool cdt_3_can_use_cxx20_format() {