+#if HAVE_ENDIAN_H
+# include <endian.h>
+#endif
+
+#ifndef BYTE_ORDER
+# ifdef __BYTE_ORDER
+# define BYTE_ORDER __BYTE_ORDER
+# endif
+#endif
+#ifndef BIG_ENDIAN
+# ifdef __BIG_ENDIAN
+# define BIG_ENDIAN __BIG_ENDIAN
+# endif
+#endif
+#if !defined(BYTE_ORDER) || !defined(BIG_ENDIAN)
+# error "Cannot determine byte order"
+#endif
+