From 6763bfcc0fbab7895514c1f954d79a2555036323 Mon Sep 17 00:00:00 2001
From: Irit Katriel <1055913+iritkatriel@users.noreply.github.com>
Date: Wed, 1 May 2024 21:51:40 +0100
Subject: [PATCH] gh-118272: set stacktop to 0 before freeing contents, to
 avoid access to invalid objects during GC (#118478)

---
 Python/frame.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/Python/frame.c b/Python/frame.c
index ec390e7426a..2bb12823572 100644
--- a/Python/frame.c
+++ b/Python/frame.c
@@ -98,10 +98,11 @@ void
 _PyFrame_ClearLocals(_PyInterpreterFrame *frame)
 {
     assert(frame->stacktop >= 0);
-    for (int i = 0; i < frame->stacktop; i++) {
+    int stacktop = frame->stacktop;
+    frame->stacktop = 0;
+    for (int i = 0; i < stacktop; i++) {
         Py_XDECREF(frame->localsplus[i]);
     }
-    frame->stacktop = 0;
     Py_CLEAR(frame->f_locals);
 }