From 6bead8f77afd2f7317eb011ca019b61ac3d90c17 Mon Sep 17 00:00:00 2001
From: Mateusz Poliwczak <mpoliwczak34@gmail.com>
Date: Mon, 7 Nov 2022 14:54:52 +0000
Subject: [PATCH] sync/atomic: disallow type conversions of atomic.Pointer[T]

Fixes #56603

Change-Id: I6af9d80201025ae4028bfaa4a62e5de9ac0c501d
GitHub-Last-Rev: e6ed5e14512e1221a3c6cb181406cf00eec07e99
GitHub-Pull-Request: golang/go#56604
Reviewed-on: https://go-review.googlesource.com/c/go/+/448275
Reviewed-by: Michael Knyszek <mknyszek@google.com>
Run-TryBot: Ian Lance Taylor <iant@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@google.com>
---
 src/sync/atomic/type.go | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/src/sync/atomic/type.go b/src/sync/atomic/type.go
index 87c98b1e77..4d466232f1 100644
--- a/src/sync/atomic/type.go
+++ b/src/sync/atomic/type.go
@@ -41,6 +41,10 @@ var _ = &Pointer[int]{}
 
 // A Pointer is an atomic pointer of type *T. The zero value is a nil *T.
 type Pointer[T any] struct {
+	// Mention T in a field to disallow conversion between Pointer types.
+	// See go.dev/issue/56603 for more details.
+	_ [0]T
+
 	_ noCopy
 	v unsafe.Pointer
 }
-- 
2.48.1