--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/hotspot/share/gc/shared/isGCActiveMark.cpp	Thu May 09 14:26:03 2019 +0200
@@ -0,0 +1,44 @@
+/*
+ * Copyright (c) 2002, 2019, 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 "gc/shared/collectedHeap.hpp"
+#include "gc/shared/isGCActiveMark.hpp"
+#include "memory/universe.hpp"
+#include "utilities/debug.hpp"
+
+// This class provides a method for block structured setting of the
+// _is_gc_active state without requiring accessors in CollectedHeap
+
+IsGCActiveMark::IsGCActiveMark() {
+  CollectedHeap* heap = Universe::heap();
+  assert(!heap->is_gc_active(), "Not reentrant");
+  heap->_is_gc_active = true;
+}
+
+IsGCActiveMark::~IsGCActiveMark() {
+  CollectedHeap* heap = Universe::heap();
+  assert(heap->is_gc_active(), "Sanity");
+  heap->_is_gc_active = false;
+}

--- a/src/hotspot/share/gc/shared/isGCActiveMark.hpp	Thu May 09 14:26:03 2019 +0200
+++ b/src/hotspot/share/gc/shared/isGCActiveMark.hpp	Thu May 09 14:26:03 2019 +0200
@@ -35,17 +35,8 @@
 
 class IsGCActiveMark : public StackObj {
  public:
-  IsGCActiveMark() {
-    CollectedHeap* heap = Universe::heap();
-    assert(!heap->is_gc_active(), "Not reentrant");
-    heap->_is_gc_active = true;
-  }
-
-  ~IsGCActiveMark() {
-    CollectedHeap* heap = Universe::heap();
-    assert(heap->is_gc_active(), "Sanity");
-    heap->_is_gc_active = false;
-  }
+  IsGCActiveMark();
+  ~IsGCActiveMark();
 };
 
 #endif // SHARE_GC_SHARED_ISGCACTIVEMARK_HPP