diff --git a/src/sync/atomic/type.go b/src/sync/atomic/type.go
index f7b8f5a3b7..2d1e621652 100644
--- a/src/sync/atomic/type.go
+++ b/src/sync/atomic/type.go
@@ -37,6 +37,10 @@ func b32(b bool) uint32 {
 
 // 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
 }