+/* Attribute const is used for functions that have no effects other than their
+ * return value, and only rely on the argument values to compute the return
+ * value. As a result, calls to it can be CSEed. Note that using memory
+ * pointed to by the arguments is not allowed for const functions.
+ */
+#ifdef HAVE_FUNC_ATTRIBUTE_CONST
+#define ATTRIBUTE_CONST __attribute__((__const__))
+#else
+#define ATTRIBUTE_CONST
+#endif
+