CanExecuteScripts's context doesn't have a JSScript*?

If the JSContext* passed into  
nsScriptSecurityManager::CanExecuteScripts does not have a JSScript*  
when walking the frames, what could that mean?


In CanExecuteScripts(), i am doing something like this:


     JSStackFrame* frame = nsnull;
     JSScript* script = nsnull;
     do {
         frame = ::JS_FrameIterator(cx, &frame);

         if (frame) {
             script = ::JS_GetFrameScript(cx, frame);
         }
     } while (frame && !script);

     if (script) {
         const char* filename = ::JS_GetScriptFilename(cx, script);
         printf("--> filename: %s\n", filename);  //check for null?
     }
     else
     {
         printf("--> no script?\n");
     }


   cx is passed into the function.


I would have thought that we would have a non-null JSScript* even for  
inlince script.

Doug Turner