--- a/Behavior.st	Wed May 04 17:53:29 2016 +0200
+++ b/Behavior.st	Wed May 04 18:52:20 2016 +0200
@@ -1423,7 +1423,6 @@
     ^ self nameWithoutPrefix
 ! !
 
-
 !Behavior methodsFor:'RefactoringBrowser'!
 
 realClass
@@ -5164,14 +5163,15 @@
 
     |setOfSelectors|
 
-    setOfSelectors := IdentitySet new.
     self methodDictionary keysAndValuesDo:[:sel :mthd |
-	(mthd referencesLiteral:someLiteralConstant) ifTrue:[
-	    setOfSelectors add:sel
-	].
+        (mthd referencesLiteral:someLiteralConstant) ifTrue:[
+            setOfSelectors isNil ifTrue:[
+                setOfSelectors := IdentitySet new.
+            ].    
+            setOfSelectors add:sel
+        ].
     ].
-
-    ^ setOfSelectors
+    ^ setOfSelectors ? #()
 
     "
      String whichSelectorsReferTo:#at: