diff --git a/difftest/Cargo.lock b/difftest/Cargo.lock
index 14b0f1a16..dc74ac0a1 100644
--- a/difftest/Cargo.lock
+++ b/difftest/Cargo.lock
@@ -134,7 +134,7 @@ dependencies = [
 ]
 
 [[package]]
-name = "dpi_t1"
+name = "dpi_t1emu"
 version = "0.1.0"
 dependencies = [
  "dpi_common",
@@ -145,7 +145,7 @@ dependencies = [
 ]
 
 [[package]]
-name = "dpi_t1rocket"
+name = "dpi_t1rocketemu"
 version = "0.1.0"
 dependencies = [
  "anyhow",
@@ -269,7 +269,7 @@ dependencies = [
 ]
 
 [[package]]
-name = "offline_t1"
+name = "offline_t1emu"
 version = "0.1.0"
 dependencies = [
  "anyhow",
@@ -285,7 +285,7 @@ dependencies = [
 ]
 
 [[package]]
-name = "offline_t1rocket"
+name = "offline_t1rocketemu"
 version = "0.1.0"
 dependencies = [
  "anyhow",
diff --git a/difftest/offline_t1emu/src/json_events.rs b/difftest/offline_t1emu/src/json_events.rs
index 60bf8a388..99bd72c96 100644
--- a/difftest/offline_t1emu/src/json_events.rs
+++ b/difftest/offline_t1emu/src/json_events.rs
@@ -162,6 +162,17 @@ impl JsonEventRunner for SpikeRunner {
 
     se.issue_idx = issue.idx as u8;
 
+    self.commit_queue.iter().for_each(|old_se| {
+      assert_eq!(
+        old_se.issue_idx, se.issue_idx,
+        "[{cycle}] Issue: new issue_idx={} ({}) should not be equal to any old event in commit_queue issue_idx={} ({}), check if the old event is retired in time",
+        se.issue_idx,
+        old_se.issue_idx,
+        se.describe_insn(),
+        old_se.describe_insn()
+      );
+    });
+
     info!(
       "[{}] SpikePeekIssue: issue_idx={}, pc={:#x}, inst={}",
       issue.cycle, issue.idx, se.pc, se.disasm
diff --git a/difftest/offline_t1rocketemu/src/json_events.rs b/difftest/offline_t1rocketemu/src/json_events.rs
index bf470a9f8..46386d3b8 100644
--- a/difftest/offline_t1rocketemu/src/json_events.rs
+++ b/difftest/offline_t1rocketemu/src/json_events.rs
@@ -337,6 +337,17 @@ impl JsonEventRunner for SpikeRunner {
 
     se.issue_idx = idx as u8;
 
+    self.commit_queue.iter().for_each(|old_se| {
+      assert_eq!(
+        old_se.issue_idx, se.issue_idx,
+        "[{cycle}] Issue: new issue_idx={} ({}) should not be equal to any old event in commit_queue issue_idx={} ({}), check if the old event is retired in time",
+        se.issue_idx,
+        old_se.issue_idx,
+        se.describe_insn(),
+        old_se.describe_insn()
+      );
+    });
+
     info!("[{cycle}] Issue: issue_idx={idx} ({})", se.describe_insn());
 
     self.commit_queue.push_front(se);