From e3fa3c48d8a4aadcf86429e9f7f6f1171914b15a Mon Sep 17 00:00:00 2001
From: Mike Pall <mike>
Date: Thu, 24 Jul 2025 15:35:56 +0200
Subject: [PATCH] Avoid out-of-range PC for stack overflow error from snapshot
 restore.

Reported by Sergey Kaplun. #1369
---
 src/lj_debug.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/src/lj_debug.c b/src/lj_debug.c
index a639cddf..f3409649 100644
--- a/src/lj_debug.c
+++ b/src/lj_debug.c
@@ -101,6 +101,7 @@ static BCPos debug_framepc(lua_State *L, GCfunc *fn, cTValue *nextframe)
   pt = funcproto(fn);
   pos = proto_bcpos(pt, ins) - 1;
 #if LJ_HASJIT
+  if (pos == NO_BCPOS) return 1;  /* Pretend it's the first bytecode. */
   if (pos > pt->sizebc) {  /* Undo the effects of lj_trace_exit for JLOOP. */
     if (bc_isret(bc_op(ins[-1]))) {
       GCtrace *T = (GCtrace *)((char *)(ins-1) - offsetof(GCtrace, startins));
-- 
2.47.2