# define STATIC_ASSERT(expr) ((void)sizeof(char[1 - 2 * !(expr)]))
#endif
+/* STATIC_ASSERT_ZERO() - verify the truth of an expression at compilation time
+ * and also produce a result of 0 to be used in constant expressions */
+#define STATIC_ASSERT_ZERO(expr) ((int)sizeof(char[0 - 2 * !(expr)]))
+
#define CONCAT_IMPL(s1, s2) s1##s2
/* CONCAT() - concatenate two tokens at preprocessing time. */