From 66c2eb6041f6970d616822e58dff00ac70d0fdce Mon Sep 17 00:00:00 2001
From: ltzmaxwell <ltz.maxwell@gmail.com>
Date: Sun, 8 Dec 2024 05:01:51 +0800
Subject: [PATCH] fix(gnovm): make `Stacktrace` correctly handle panics with
 `len(Stmts) == 0` (#3273)

While finalizing the realm, all statements in the machine have been
popped out. A necessary check must be performed during stack trace
handling.
<!-- please provide a detailed description of the changes made in this
pull request. -->

<details><summary>Contributors' checklist...</summary>

- [ ] Added new tests, or not needed, or not feasible
- [ ] Provided an example (e.g. screenshot) to aid review or the PR is
self-explanatory
- [ ] Updated the official documentation or not needed
- [ ] No breaking changes were made, or a `BREAKING CHANGE: xxx` message
was included in the description
- [ ] Added references to related issues and PRs
- [ ] Provided any useful hints for running manual tests
</details>

Co-authored-by: Petar Dambovaliev <petar.atanasov.1987@gmail.com>
---
 gnovm/pkg/gnolang/machine.go | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/gnovm/pkg/gnolang/machine.go b/gnovm/pkg/gnolang/machine.go
index 4f4c7c188f3..b48c0742e6f 100644
--- a/gnovm/pkg/gnolang/machine.go
+++ b/gnovm/pkg/gnolang/machine.go
@@ -401,7 +401,7 @@ func destar(x Expr) Expr {
 // Stacktrace returns the stack trace of the machine.
 // It collects the executions and frames from the machine's frames and statements.
 func (m *Machine) Stacktrace() (stacktrace Stacktrace) {
-	if len(m.Frames) == 0 {
+	if len(m.Frames) == 0 || len(m.Stmts) == 0 {
 		return
 	}