From 1603a1029f44f0fdc87c65b02063229962194f84 Mon Sep 17 00:00:00 2001
From: Irit Katriel <1055913+iritkatriel@users.noreply.github.com>
Date: Mon, 20 Jun 2022 17:13:39 +0100
Subject: GH-93249: relax overly strict assertion on bounds->ar_start
 (GH-93961)

---
 Objects/codeobject.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

(limited to 'Objects/codeobject.c')

diff --git a/Objects/codeobject.c b/Objects/codeobject.c
index c1f696dc572..707de11d479 100644
--- a/Objects/codeobject.c
+++ b/Objects/codeobject.c
@@ -826,6 +826,11 @@ next_code_delta(PyCodeAddressRange *bounds)
 static int
 previous_code_delta(PyCodeAddressRange *bounds)
 {
+    if (bounds->ar_start == 0) {
+        // If we looking at the first entry, the
+        // "previous" entry has an implicit length of 1.
+        return 1;
+    }
     const uint8_t *ptr = bounds->opaque.lo_next-1;
     while (((*ptr) & 128) == 0) {
         ptr--;
@@ -869,7 +874,7 @@ static void
 retreat(PyCodeAddressRange *bounds)
 {
     ASSERT_VALID_BOUNDS(bounds);
-    assert(bounds->ar_start > 0);
+    assert(bounds->ar_start >= 0);
     do {
         bounds->opaque.lo_next--;
     } while (((*bounds->opaque.lo_next) & 128) == 0);
-- 
cgit v1.2.3