Index: generic/nsfAPI.h
===================================================================
diff -u -r7a3ce03f8d70724a621e75469908f0d3aa57ba3e -rb36642f41c9d2ff8035f9cce982789b16dd50385
--- generic/nsfAPI.h	(.../nsfAPI.h)	(revision 7a3ce03f8d70724a621e75469908f0d3aa57ba3e)
+++ generic/nsfAPI.h	(.../nsfAPI.h)	(revision b36642f41c9d2ff8035f9cce982789b16dd50385)
@@ -4,7 +4,21 @@
  * part of the Next Scripting Framework.
  */
 
+#if !defined(likely) 
+# if defined(__GNUC__) && __GNUC__ > 2
+/* Use gcc branch prediction hint to minimize cost of e.g. DTrace
+ * ENABLED checks. 
+ */
+#  define unlikely(x) (__builtin_expect((x), 0))
+#  define likely(x) (__builtin_expect((x), 1))
+# else
+#  define unlikely(x) (x)
+#  define likely(x) (x)
+# endif
+#endif
 
+
+
 enum InfomethodsubcmdIdx {InfomethodsubcmdNULL, InfomethodsubcmdArgsIdx, InfomethodsubcmdBodyIdx, InfomethodsubcmdDefinitionIdx, InfomethodsubcmdExistsIdx, InfomethodsubcmdRegistrationhandleIdx, InfomethodsubcmdDefinitionhandleIdx, InfomethodsubcmdHandleIdx, InfomethodsubcmdOriginIdx, InfomethodsubcmdParameterIdx, InfomethodsubcmdParametersyntaxIdx, InfomethodsubcmdTypeIdx, InfomethodsubcmdPreconditionIdx, InfomethodsubcmdPostconditionIdx, InfomethodsubcmdSubmethodsIdx, InfomethodsubcmdReturnsIdx};
 
 static int ConvertToInfomethodsubcmd(Tcl_Interp *interp, Tcl_Obj *objPtr, Nsf_Param CONST *pPtr,