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diff --git a/sal/inc/osl/doublecheckedlocking.h b/sal/inc/osl/doublecheckedlocking.h
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+/*************************************************************************
+ *
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * Copyright 2000, 2010 Oracle and/or its affiliates.
+ *
+ * OpenOffice.org - a multi-platform office productivity suite
+ *
+ * This file is part of OpenOffice.org.
+ *
+ * OpenOffice.org is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License version 3
+ * only, as published by the Free Software Foundation.
+ *
+ * OpenOffice.org 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 Lesser General Public License version 3 for more details
+ * (a copy is included in the LICENSE file that accompanied this code).
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * version 3 along with OpenOffice.org.  If not, see
+ * <http://www.openoffice.org/license.html>
+ * for a copy of the LGPLv3 License.
+ *
+ ************************************************************************/
+
+#if !defined INCLUDED_OSL_DOUBLECHECKEDLOCKING_H
+#define INCLUDED_OSL_DOUBLECHECKEDLOCKING_H
+
+#if defined __cplusplus
+extern "C" {
+#endif /* __cplusplus */
+
+/** A platform specific macro needed to make double-checked locking work.
+
+    See
+    <http://www.cs.umd.edu/~pugh/java/memoryModel/DoubleCheckedLocking.html>
+    for a description of double-checked locking, why it is broken, and how it
+    can be fixed.  On platforms where it is necessary, this macro will expand
+    to some memory barrier instruction.  On many platforms, double-checked
+    locking works as it is, though, so on those platforms this macro will be
+    empty.  This is a macro instead of a (C++ inline) function to allow for
+    maximum performance in both C and C++.
+
+    If possible, use the rtl_Instance template instead of explicitly spelling
+    out the double-checked locking pattern.  There are few cases where you
+    will have to spell it out explicitly (e.g., the logic of a certain
+    instance of the pattern is too complex to be mapped to the template, or
+    some compiler refuses to compile a template instantiation due to internal
+    compiler errors), though, and you should always call this macro at the
+    right places then:
+
+      static T * pInstance = 0;
+
+      T * p = pInstance;
+      if (!p)
+      {
+          Guard aGuard(aMutex);
+          p = pInstance;
+          if (!p)
+          {
+              p = ...;
+              OSL_DOUBLE_CHECKED_LOCKING_MEMORY_BARRIER();
+              pInstance = p;
+          }
+      }
+      else
+          OSL_DOUBLE_CHECKED_LOCKING_MEMORY_BARRIER();
+      return p;
+
+    One extra advantage of this macro is that it makes it easier to find all
+    places where double-checked locking is used.
+ */
+#define OSL_DOUBLE_CHECKED_LOCKING_MEMORY_BARRIER() /* empty */
+
+#if defined __cplusplus
+}
+#endif /* __cplusplus */
+
+#endif /* INCLUDED_OSL_DOUBLECHECKEDLOCKING_H */