diff --git a/include/boost/config/compiler/visualc.hpp b/include/boost/config/compiler/visualc.hpp
index 5c52c766..e2ea2702 100644
--- a/include/boost/config/compiler/visualc.hpp
+++ b/include/boost/config/compiler/visualc.hpp
@@ -205,6 +205,7 @@
 #if (_MSC_VER < 1911) || (_MSVC_LANG < 201703)
 #  define BOOST_NO_CXX17_STRUCTURED_BINDINGS
 #  define BOOST_NO_CXX17_IF_CONSTEXPR
+// Let the defaults handle these now:
 //#  define BOOST_NO_CXX17_HDR_OPTIONAL
 //#  define BOOST_NO_CXX17_HDR_STRING_VIEW
 #endif