From f522d882373067ab79ea0fdc30be6150eeccb1fd Mon Sep 17 00:00:00 2001
From: Andrew Paseltiner <apaseltiner@gmail.com>
Date: Mon, 29 Feb 2016 22:03:23 -0500
Subject: Explicitly opt out of `Sync` for `cell` and `mpsc` types

These types were already `!Sync`, but this improves error messages when
they are used in contexts that require `Sync`, aligning them with
conventions used with `Rc`, among others.
---
 src/libcore/cell.rs | 6 ++++++
 1 file changed, 6 insertions(+)

(limited to 'src/libcore')

diff --git a/src/libcore/cell.rs b/src/libcore/cell.rs
index 255c846244b..144adde12e4 100644
--- a/src/libcore/cell.rs
+++ b/src/libcore/cell.rs
@@ -241,6 +241,9 @@ impl<T:Copy> Cell<T> {
 #[stable(feature = "rust1", since = "1.0.0")]
 unsafe impl<T> Send for Cell<T> where T: Send {}
 
+#[stable(feature = "rust1", since = "1.0.0")]
+impl<T> !Sync for Cell<T> {}
+
 #[stable(feature = "rust1", since = "1.0.0")]
 impl<T:Copy> Clone for Cell<T> {
     #[inline]
@@ -461,6 +464,9 @@ impl<T: ?Sized> RefCell<T> {
 #[stable(feature = "rust1", since = "1.0.0")]
 unsafe impl<T: ?Sized> Send for RefCell<T> where T: Send {}
 
+#[stable(feature = "rust1", since = "1.0.0")]
+impl<T: ?Sized> !Sync for RefCell<T> {}
+
 #[stable(feature = "rust1", since = "1.0.0")]
 impl<T: Clone> Clone for RefCell<T> {
     #[inline]
-- 
cgit 1.4.1-3-g733a5