diff --git a/src/lib/CoAlgReasoner.ml b/src/lib/CoAlgReasoner.ml
index 6a54b71fdf7213bb37ba1cd9a570333c51ea9500..255dd9dcb9ce5f2a2599e27c3dea5591ab3dbf98 100644
--- a/src/lib/CoAlgReasoner.ml
+++ b/src/lib/CoAlgReasoner.ml
@@ -127,7 +127,7 @@ let propagateSatMu () =
     | Unsat -> ()
     | Sat ->
        setAddState setSatStates state
-    | Expandable
+    | Expandable -> ()
     | Open ->
        if stateGetStatus state == Open && List.length (stateGetRules state) == 0
        then begin
@@ -148,7 +148,7 @@ let propagateSatMu () =
     | Unsat -> ()
     | Sat ->
        setAddCore setSatCores core
-    | Expandable
+    | Expandable -> ()
     | Open ->
        setAddCore setCores core;
        if bsetCompare (coreGetDeferral core) emptySet == 0