From fcf8042b06c24688374d29791060bc90ee1c2867 Mon Sep 17 00:00:00 2001
From: nyash-codex <codex@nyash.local>
Date: Fri, 26 Sep 2025 14:47:52 +0900
Subject: [PATCH] builder: propagate value_types and value_origin_newbox in
 pin_to_slot (stabilize rewrite/type inference across pin/PHI)

---
 src/mir/builder/utils.rs | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/src/mir/builder/utils.rs b/src/mir/builder/utils.rs
index 65a54271..9a9d1a25 100644
--- a/src/mir/builder/utils.rs
+++ b/src/mir/builder/utils.rs
@@ -218,6 +218,13 @@ impl super::MirBuilder {
         if super::utils::builder_debug_enabled() || std::env::var("NYASH_PIN_TRACE").ok().as_deref() == Some("1") {
             super::utils::builder_debug_log(&format!("pin slot={} src={} dst={}", slot_name, v.0, dst.0));
         }
+        // Propagate lightweight metadata so downstream resolution/type inference remains stable
+        if let Some(t) = self.value_types.get(&v).cloned() {
+            self.value_types.insert(dst, t);
+        }
+        if let Some(cls) = self.value_origin_newbox.get(&v).cloned() {
+            self.value_origin_newbox.insert(dst, cls);
+        }
         self.variable_map.insert(slot_name, dst);
         Ok(dst)
     }