diff --git a/src/tools/msvc/Mkvcbuild.pm b/src/tools/msvc/Mkvcbuild.pm
index 99f39caa5..4f51c12f2 100644
--- a/src/tools/msvc/Mkvcbuild.pm
+++ b/src/tools/msvc/Mkvcbuild.pm
@@ -182,7 +182,7 @@ sub mkvcbuild
 		'syncrep_gram.y');
 	$postgres->AddFiles('src/backend/utils/adt', 'jsonpath_scan.l',
 		'jsonpath_gram.y');
-	$postgres->AddDefine('BUILDING_DLL');
+	# $postgres->AddDefine('BUILDING_DLL');
 	$postgres->AddLibrary('secur32.lib');
 	$postgres->AddLibrary('ws2_32.lib');
 	$postgres->AddLibrary('wldap32.lib') if ($solution->{options}->{ldap});
