#if defined(__GNUC__)
# define UNUSED __attribute__((__unused__))
# define NORETURN __attribute__((__noreturn__))
-# if __GNUC__>3 || (__GNUC__==3 && __GNUC_MINOR__>=3)
+# define CONST __attribute__((__const__))
+# if __GNUC__*0x10000 + __GNUC_MINOR__*0x100 + __GNUC_PATCHLEVEL__ >= 0x30300
# define NONNULL(ARGS) __attribute__((__nonnull__ ARGS))
# define ALWAYSINLINE __attribute__((__always_inline__))
# else
# define NONNULL(ARGS)
# define ALWAYSINLINE
+# define PURE
# endif
-# if __GNUC__>3
+# if __GNUC__*0x10000 + __GNUC_MINOR__*0x100 + __GNUC_PATCHLEVEL__ >= 0x30303
# define PURE __attribute__((__pure__))
# else
# define PURE
# define NORETURN
# define ALWAYSINLINE
# define PURE
+# define CONST
+#endif
+
+#if !defined(__builtin_expect) && (__GNUC__+0)<3
+# define __builtin_expect(foo,bar) (foo)
#endif
#if !defined(__STDC_VERSION__) || (__STDC_VERSION__<199901L)