From 08cc15d87295500d46e3bb16e5c14262e79bf48e Mon Sep 17 00:00:00 2001
From: Malte Ubl <malte@vercel.com>
Date: Mon, 26 Oct 2026 07:07:50 -0700
Subject: [PATCH] Keep canonical degraded entries when a declaration retry
 rolls back

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
---
 packages/compiler/src/frontend/lowering/lowerer.ts | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/packages/compiler/src/frontend/lowering/lowerer.ts b/packages/compiler/src/frontend/lowering/lowerer.ts
index 7d3b4d38d..eee126efb 100644
--- a/packages/compiler/src/frontend/lowering/lowerer.ts
+++ b/packages/compiler/src/frontend/lowering/lowerer.ts
@@ -13215,7 +13215,15 @@ export class Lowerer {
         const prior = this.degradedTypes.get(id);
         degraded.push({
           id,
-          prior: prior === undefined ? undefined : { ...prior },
+          prior:
+            prior === undefined
+              ? undefined
+              : {
+                  lenient: prior.lenient,
+                  code: prior.code,
+                  reason: prior.reason,
+                  ...(prior.canonical === true ? { canonical: true as const } : {}),
+                },
         });
         this.degradeType(type, diag.code, diag.message);
         const canonical = this.isCanonicalDegraded(id);