diff --git a/libcxx/test/support/test_macros.h b/libcxx/test/support/test_macros.h
--- a/libcxx/test/support/test_macros.h
+++ b/libcxx/test/support/test_macros.h
@@ -366,7 +366,7 @@
 #   define TEST_HAS_NO_UNICODE
 #endif
 
-#if defined(_LIBCPP_HAS_NO_INT128) || defined(TEST_COMPILER_MSVC)
+#if defined(_LIBCPP_HAS_NO_INT128) || defined(_MSVC_STL_VERSION)
 #   define TEST_HAS_NO_INT128
 #endif