+/* Thanks to Andrew Tridgell's (SAMBA's) talloc for this definition of
+ * unlikely. The talloc source code comes to us via the GNU LGPL v. 3.
+ */
+/* these macros gain us a few percent of speed on gcc */
+#if (__GNUC__ >= 3)
+/* the strange !! is to ensure that __builtin_expect() takes either 0 or 1
+ as its first argument */
+#ifndef likely
+#define likely(x) __builtin_expect(!!(x), 1)
+#endif
+#ifndef unlikely
+#define unlikely(x) __builtin_expect(!!(x), 0)
+#endif
+#else
+#ifndef likely
+#define likely(x) (x)
+#endif
+#ifndef unlikely
+#define unlikely(x) (x)
+#endif
+#endif
+
+/* These value numbers are chosen to be sup compatible (for now at
+ * least). */