--- a/absyntax/absyntax.def	Fri Feb 03 10:54:35 2012 +0000
+++ b/absyntax/absyntax.def	Fri Feb 03 14:43:14 2012 +0000
@@ -1099,7 +1099,15 @@
 /* fb_name '(' [param_assignment_list] ')' */
 /*    formal_param_list -> may be NULL ! */
 /* nonformal_param_list -> may be NULL ! */
-SYM_REF3(fb_invocation_c, fb_name, formal_param_list, nonformal_param_list)
+/* NOTES:
+ *    The parameter 'called_fb_declaration'... 
+ *       ...is used to pass data between two passes of stage 3.
+ *       (actually set in fill_candidate_datatypes_c, and used in narrow_candidate_datatypes_c and print_datatypes_error_c).
+ *       This allows fill_candidate_datatypes_c to figure out whether it is a valid FB call,
+ *       and let the other classes handle it aproproately.
+ *       It could also be used in stage 4, if required.
+ */
+SYM_REF3(fb_invocation_c, fb_name, formal_param_list, nonformal_param_list, symbol_c *called_fb_declaration;)
 
 /* helper symbol for fb_invocation */
 /* param_assignment_list ',' param_assignment */