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+/* Determine alignment of types.
+ Copyright (C) 2003-2004, 2006, 2009 Free Software Foundation, Inc.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 3, or (at your option)
+ any later version.
+
+ This program 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 for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software Foundation,
+ Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */
+
+#ifndef _ALIGNOF_H
+#define _ALIGNOF_H
+
+#include <stddef.h>
+
+/* Determine the alignment of a type at compile time. */
+#if defined __GNUC__
+# define alignof __alignof__
+#elif defined __cplusplus
+ template <class type> struct alignof_helper { char __slot1; type __slot2; };
+# define alignof(type) offsetof (alignof_helper<type>, __slot2)
+#else
+# define alignof(type) offsetof (struct { char __slot1; type __slot2; }, __slot2)
+#endif
+
+#endif /* _ALIGNOF_H */