diff --git a/cgen.scm b/cgen.scm
index fd354ba8..7bf3fe4b 100644
--- a/cgen.scm
+++ b/cgen.scm
@@ -421,7 +421,7 @@
      ((eq? p 'Cyc-get-cvar)          "Cyc_get_cvar")
      ((eq? p 'Cyc-set-cvar!)         "Cyc_set_cvar")
      ((eq? p 'Cyc-cvar?)             "Cyc_is_cvar")
-     ((eq? p 'has-cycle?)            "Cyc_has_cycle")
+     ((eq? p 'Cyc-has-cycle?)        "Cyc_has_cycle")
      ((eq? p '+)                     "__sum")
      ((eq? p '-)                     "__sub")
      ((eq? p '*)                     "__mul")
diff --git a/eval.scm b/eval.scm
index b986c82e..8a96514d 100644
--- a/eval.scm
+++ b/eval.scm
@@ -188,7 +188,7 @@
       (list 'Cyc-get-cvar Cyc-get-cvar)
       (list 'Cyc-set-cvar! Cyc-set-cvar!)
       (list 'Cyc-cvar? Cyc-cvar?)
-      (list 'has-cycle? has-cycle?)
+      (list 'Cyc-has-cycle? Cyc-has-cycle?)
       (list '+ +)
       (list '- -)
       (list '* *)
diff --git a/runtime.h b/runtime.h
index 7441ded4..a64ae49c 100644
--- a/runtime.h
+++ b/runtime.h
@@ -565,8 +565,8 @@ static object Cyc_has_cycle(object lst) {
         if (nullp(cdr(fast_lst))) return boolean_f;
         if (Cyc_is_cons(cdr(fast_lst)) == boolean_f) return boolean_f;
         if (is_object_type(car(slow_lst)) && 
-            !Cyc_is_boolean(car(slow_lst)) && // Avoid expected dupes
-            !Cyc_is_symbol(car(slow_lst)) &&  // 
+            boolean_f == Cyc_is_boolean(car(slow_lst)) && // Avoid expected dupes
+            boolean_f == Cyc_is_symbol(car(slow_lst)) &&  // 
             eq(car(slow_lst), car(fast_lst))) return boolean_t;
 
         slow_lst = cdr(slow_lst);
@@ -1154,7 +1154,7 @@ static void _set_91car_67(object cont, object args) {
     return_funcall1(cont, Cyc_set_car(car(args), cadr(args))); }
 static void _set_91cdr_67(object cont, object args) { 
     return_funcall1(cont, Cyc_set_cdr(car(args), cadr(args))); }
-static void _has_91cycle_127(object cont, object args) { 
+static void _Cyc_91has_91cycle_127(object cont, object args) { 
     return_funcall1(cont, Cyc_has_cycle(car(args))); }
 static void __87(object cont, object args) {
     __sum(i, car(args), cadr(args));
@@ -1295,7 +1295,7 @@ defprimitive(Cyc_91global_91vars, Cyc-global-vars, &_Cyc_91global_91vars); /* Cy
 defprimitive(Cyc_91get_91cvar, Cyc-get-cvar, &_Cyc_91get_91cvar); /* Cyc-get-cvar */
 defprimitive(Cyc_91set_91cvar_67, Cyc-set-cvar!, &_Cyc_91set_91cvar_67); /* Cyc-set-cvar! */
 defprimitive(Cyc_91cvar_127, Cyc-cvar?, &_Cyc_91cvar_127); /* Cyc-cvar? */
-defprimitive(has_91cycle_127, has-cycle?, &_has_91cycle_127); /* has-cycle? */
+defprimitive(Cyc_91has_91cycle_127, Cyc-has-cycle?, &_Cyc_91has_91cycle_127); /* Cyc-has-cycle? */
 defprimitive(_87, +, &__87); /* + */
 defprimitive(_91, -, &__91); /* - */
 defprimitive(_85, *, &__85); /* * */
diff --git a/trans.scm b/trans.scm
index d2293384..e65316ee 100644
--- a/trans.scm
+++ b/trans.scm
@@ -617,7 +617,7 @@
      Cyc-get-cvar
      Cyc-set-cvar!
      Cyc-cvar? ;; Cyclone-specific
-     has-cycle?
+     Cyc-has-cycle?
      +
      -
      *