diff --git a/compiler/symbase.pas b/compiler/symbase.pas
index 7333bc4606..94e5777694 100644
--- a/compiler/symbase.pas
+++ b/compiler/symbase.pas
@@ -284,6 +284,10 @@ implementation
         while assigned(st.defowner) do
           begin
             st:=st.defowner.owner;
+            { this can happen for specializations of routines that are not yet
+              owned cause they might be thrown away again }
+            if not assigned(st) then
+              break;
             { the flag is already set, so by definition it is set in the
               owning symtables as well }
             if option in st.tableoptions then