@@ -420,9 +420,9 @@
 				}
 				else
 				{
 					Value v;
-					try { v = evlay.lift(new BottomValue, ctx, pos); } catch { v = new BottomValue; }
+					try { v = evlay.lift(new BottomValue, ctx, pos); } catch { return nonMemoizedRun(); }
 					memo[memokey] = tuple(v, 0);
 				}
 
 				Value r = nonMemoizedRun();