From 4c0f0b90a4f4b33d1c1af7b7415c27ad105e6264 Mon Sep 17 00:00:00 2001
From: Peter Zhu <peter@peterzhu.ca>
Date: Thu, 29 Feb 2024 11:07:53 -0500
Subject: [PATCH] Assume that FL_FINALIZE is in finalizer_table

If FL_FINALIZE is set but not in finalizer_table, then rb_bug.
---
 gc.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/gc.c b/gc.c
index 2034b469cd..e84c4e1462 100644
--- a/gc.c
+++ b/gc.c
@@ -4043,11 +4043,15 @@ rb_gc_copy_finalizer(VALUE dest, VALUE obj)
     st_data_t data;
 
     if (!FL_TEST(obj, FL_FINALIZE)) return;
-    if (st_lookup(finalizer_table, obj, &data)) {
+
+    if (RB_LIKELY(st_lookup(finalizer_table, obj, &data))) {
         table = (VALUE)data;
         st_insert(finalizer_table, dest, table);
         FL_SET(dest, FL_FINALIZE);
     }
+    else {
+        rb_bug("rb_gc_copy_finalizer: FL_FINALIZE set but not found in finalizer_table: %s", obj_info(obj));
+    }
 }
 
 static VALUE