Make ostream operators opt in to reduce the risk of ODR violations

2022-02-04 15:06:45 -08:00
parent 8a21e328b8
commit f055ebbd25
5 changed files with 35 additions and 43 deletions
@@ -1016,7 +1016,11 @@ struct fallback_formatter {
 // Specifies if T has an enabled fallback_formatter specialization.
 template <typename T, typename Char>
 using has_fallback_formatter =
+#ifdef FMT_DEPRECATED_OSTREAM
    std::is_constructible<fallback_formatter<T, Char>>;
+#else
+    std::false_type;
+#endif

 struct view {};