--- a/src/hotspot/share/runtime/arguments.cpp	Wed Sep 04 13:06:04 2019 +0200
+++ b/src/hotspot/share/runtime/arguments.cpp	Wed Sep 04 13:06:44 2019 +0200
@@ -628,14 +628,7 @@
   }
 }
 
-extern bool lookup_special_flag_ext(const char *flag_name, SpecialFlag& flag);
-
 static bool lookup_special_flag(const char *flag_name, SpecialFlag& flag) {
-  // Allow extensions to have priority
-  if (lookup_special_flag_ext(flag_name, flag)) {
-    return true;
-  }
-
   for (size_t i = 0; special_jvm_flags[i].name != NULL; i++) {
     if ((strcmp(special_jvm_flags[i].name, flag_name) == 0)) {
       flag = special_jvm_flags[i];

--- a/src/hotspot/share/runtime/arguments_ext.cpp	Wed Sep 04 13:06:04 2019 +0200
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,30 +0,0 @@
-/*
- * Copyright (c) 2016, Oracle and/or its affiliates. All rights reserved.
- * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
- *
- * This code is free software; you can redistribute it and/or modify it
- * under the terms of the GNU General Public License version 2 only, as
- * published by the Free Software Foundation.
- *
- * This code is distributed in the hope that it will be useful, but WITHOUT
- * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
- * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
- * version 2 for more details (a copy is included in the LICENSE file that
- * accompanied this code).
- *
- * You should have received a copy of the GNU General Public License version
- * 2 along with this work; if not, write to the Free Software Foundation,
- * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
- *
- * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
- * or visit www.oracle.com if you need additional information or have any
- * questions.
- *
- */
-
-#include "precompiled.hpp"
-#include "runtime/arguments.hpp"
-
-bool lookup_special_flag_ext(const char *flag_name, SpecialFlag& flag) {
-  return false;
-}