diff --git a/src/engine/rv64/tran.c b/src/engine/rv64/tran.c
index 4c2d97ca0e185935d7189c1aaa15c011d9d6742f..238ff8ac2f3c1f852d3a122259ae0f8ea6058209 100644
--- a/src/engine/rv64/tran.c
+++ b/src/engine/rv64/tran.c
@@ -53,9 +53,10 @@ static int find_topn_min(TB **top) {
 static TB** find_topn_tb() {
   static TB *top[TOP_N];
   TB *p = head.next;;
+  TB empty = { .pc = -1, .hit_time = 0, .guest_nr_instr = 0 };
   int i;
   for (i = 0; i < TOP_N; i ++) {
-    Assert(p != NULL, "i = %d", i);
+    if (p == NULL) p = &empty;
     top[i] = p;
     p = p->next;
   }