fix bug reported by abalkin

theano/scan_module/scan_opt.py

@@ -837,9 +837,9 @@ class ScanSaveMem(gof.Optimizer):
                     if not (idx in replaced_outs) and not idx in not_required:
                         nw_pos = compress_map[idx]
                         old_new += [(o, new_outs[nw_pos])]
-
+                remove = [ x[0].owner for x in old_new]
                 fgraph.replace_all_validate_remove(old_new,
-                                                   remove=[node],
+                                                   remove=remove,
                                                    reason='scan_save_mem')
 
     def apply(self, fgraph):