From c8663eec6a667ae6e7571297cb15192425311c33 Mon Sep 17 00:00:00 2001
From: Aapo Alasuutari <aapo.alasuutari@gmail.com>
Date: Fri, 29 Aug 2025 23:29:46 +0300
Subject: Introduce CoerceShared lang item and trait

---
 library/core/src/marker.rs | 9 +++++++++
 1 file changed, 9 insertions(+)

(limited to 'library/core/src')

diff --git a/library/core/src/marker.rs b/library/core/src/marker.rs
index d03d7a43469..8541a5b91cd 100644
--- a/library/core/src/marker.rs
+++ b/library/core/src/marker.rs
@@ -1372,3 +1372,12 @@ pub trait CoercePointeeValidated {
 pub trait Reborrow {
     // Empty.
 }
+
+/// Allows reborrowable value to be reborrowed as shared, creating a copy of
+/// that disables the source for writes for the lifetime of the copy.
+#[lang = "coerce_shared"]
+#[unstable(feature = "reborrow", issue = "145612")]
+pub trait CoerceShared: Reborrow {
+    /// The type of this value when reborrowed as shared.
+    type Target: Copy;
+}
-- 
cgit 1.4.1-3-g733a5