From 3a4aa2a54127e2b633aadabf2f75930e6d0f1dbf Mon Sep 17 00:00:00 2001
From: Mark Thom <markjordanthom@gmail.com>
Date: Thu, 12 Jan 2023 23:46:57 -0700
Subject: [PATCH] tighten deallocate truncation of stack (#1686)

---
 src/machine/machine_state_impl.rs | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/src/machine/machine_state_impl.rs b/src/machine/machine_state_impl.rs
index 00e17649..a77fda72 100644
--- a/src/machine/machine_state_impl.rs
+++ b/src/machine/machine_state_impl.rs
@@ -2784,8 +2784,11 @@ impl MachineState {
         self.cp = frame.prelude.cp;
         self.e = frame.prelude.e;
 
-        if e > self.b {
-            self.stack.truncate(e);
+        if self.e > self.b {
+            let frame = self.stack.index_and_frame(self.e);
+            let size = AndFrame::size_of(frame.prelude.univ_prelude.num_cells);
+
+            self.stack.truncate(self.e + size);
         }
 
         self.p += 1;
-- 
2.54.0