diff --git a/include/gsl/span b/include/gsl/span
index b668e71..f11ea6a 100644
--- a/include/gsl/span
+++ b/include/gsl/span
@@ -68,11 +68,11 @@ namespace std
 // array is only used for a few constructors, so pulling the entire header is unnecessary for span.
 // The end user's logic will pull in the actual definition of array if they need it.
 template <class Type, std::size_t Sz>
-#if defined(_MSC_VER) || (defined(__GNUC__) && !defined(__clang__))
-class array;
-#else
+#if defined(__clang__) || defined(__APPLE__)
 struct array;
-#endif // defined(_MSC_VER) || (defined(__GNUC__) && !defined(__clang__))
+#else
+class array;
+#endif // defined(__clang__) || defined(__APPLE__)
 }
 
 namespace gsl