diff --git a/src/google/protobuf/port_def.inc b/src/google/protobuf/port_def.inc
index 887a372696ee..3e39f915f64e 100644
--- a/src/google/protobuf/port_def.inc
+++ b/src/google/protobuf/port_def.inc
@@ -388,6 +388,10 @@
 #undef IGNORE
 #pragma push_macro("IN")
 #undef IN
+#pragma push_macro("OUT")
+#undef OUT
+#pragma push_macro("OPTIONAL")
+#undef OPTIONAL
 #pragma push_macro("min")
 #undef min
 #pragma push_macro("max")
diff --git a/src/google/protobuf/port_undef.inc b/src/google/protobuf/port_undef.inc
index dc61ba18d4bd..80822b470a9a 100644
--- a/src/google/protobuf/port_undef.inc
+++ b/src/google/protobuf/port_undef.inc
@@ -74,6 +74,8 @@
 #pragma pop_macro("GetMessage")
 #pragma pop_macro("IGNORE")
 #pragma pop_macro("IN")
+#pragma pop_macro("OUT")
+#pragma pop_macro("OPTIONAL")
 #pragma pop_macro("min")
 #pragma pop_macro("max")
 #endif