From 5bcfc53d6fa5518a194f2d0771830eb961180991 Mon Sep 17 00:00:00 2001
From: Jean Boussier <jean.boussier@gmail.com>
Date: Thu, 7 Aug 2025 14:44:48 +0200
Subject: [PATCH] set.c: use `rb_gc_mark_and_move`

The `p->field = rb_gc_location(p->field)` isn't ideal because it means all
references are rewritten on compaction, regardless of whether the referenced
object has moved. This isn't good for caches nor for Copy-on-Write.

`rb_gc_mark_and_move` avoid needless writes, and most of the time allow to
have a single function for both marking and updating references.
---
 set.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/set.c b/set.c
index f83fb0880c..c589fb4523 100644
--- a/set.c
+++ b/set.c
@@ -172,9 +172,7 @@ set_foreach_replace(st_data_t key, st_data_t argp, int error)
 static int
 set_replace_ref(st_data_t *key, st_data_t argp, int existing)
 {
-    if (rb_gc_location((VALUE)*key) != (VALUE)*key) {
-        *key = rb_gc_location((VALUE)*key);
-    }
+    rb_gc_mark_and_move((VALUE *)key);
 
     return ST_CONTINUE;
 }