diff --git a/library/std/src/sync/mpsc/mod.rs b/library/std/src/sync/mpsc/mod.rs
index 0e0c87d1c748e..71ff4237d007d 100644
--- a/library/std/src/sync/mpsc/mod.rs
+++ b/library/std/src/sync/mpsc/mod.rs
@@ -347,8 +347,8 @@ pub struct Sender<T> {
#[stable(feature = "rust1", since = "1.0.0")]
unsafe impl<T: Send> Send for Sender<T> {}
-#[stable(feature = "rust1", since = "1.0.0")]
-impl<T> !Sync for Sender<T> {}
+#[stable(feature = "mpsc_sender_sync", since = "CURRENT_RUSTC_VERSION")]
+unsafe impl<T: Send> Sync for Sender<T> {}
/// The sending-half of Rust's synchronous [`sync_channel`] type.
///
diff --git a/tests/ui/async-await/issue-70935-complex-spans.drop_tracking.stderr b/tests/ui/async-await/issue-70935-complex-spans.drop_tracking.stderr
index 721234aa4a782..f80bb4242aa70 100644
--- a/tests/ui/async-await/issue-70935-complex-spans.drop_tracking.stderr
+++ b/tests/ui/async-await/issue-70935-complex-spans.drop_tracking.stderr
@@ -1,18 +1,25 @@
-error[E0277]: `Sender<i32>` cannot be shared between threads safely
- --> $DIR/issue-70935-complex-spans.rs:13:45
+error[E0277]: `*mut ()` cannot be shared between threads safely
+ --> $DIR/issue-70935-complex-spans.rs:18:23
|
-LL | fn foo(tx: std::sync::mpsc::Sender<i32>) -> impl Future + Send {
- | ^^^^^^^^^^^^^^^^^^ `Sender<i32>` cannot be shared between threads safely
+LL | fn foo(x: NotSync) -> impl Future + Send {
+ | ^^^^^^^^^^^^^^^^^^ `*mut ()` cannot be shared between threads safely
|
- = help: the trait `Sync` is not implemented for `Sender<i32>`
- = note: required for `&Sender<i32>` to implement `Send`
+ = help: within `NotSync`, the trait `Sync` is not implemented for `*mut ()`
+note: required because it appears within the type `PhantomData<*mut ()>`
+ --> $SRC_DIR/core/src/marker.rs:LL:COL
+note: required because it appears within the type `NotSync`
+ --> $DIR/issue-70935-complex-spans.rs:12:8
+ |
+LL | struct NotSync(PhantomData<*mut ()>);
+ | ^^^^^^^
+ = note: required for `&NotSync` to implement `Send`
note: required because it's used within this closure
- --> $DIR/issue-70935-complex-spans.rs:17:13
+ --> $DIR/issue-70935-complex-spans.rs:22:13
|
-LL | baz(|| async{
+LL | baz(|| async {
| ^^
note: required because it's used within this `async fn` body
- --> $DIR/issue-70935-complex-spans.rs:10:67
+ --> $DIR/issue-70935-complex-spans.rs:15:67
|
LL | async fn baz<T>(_c: impl FnMut() -> T) where T: Future<Output=()> {
| ___________________________________________________________________^
@@ -20,11 +27,11 @@ LL | | }
| |_^
= note: required because it captures the following types: `ResumeTy`, `impl Future<Output = ()>`, `()`
note: required because it's used within this `async` block
- --> $DIR/issue-70935-complex-spans.rs:16:5
+ --> $DIR/issue-70935-complex-spans.rs:21:5
|
LL | / async move {
-LL | | baz(|| async{
-LL | | foo(tx.clone());
+LL | | baz(|| async {
+LL | | foo(x.clone());
LL | | }).await;
LL | | }
| |_____^
diff --git a/tests/ui/async-await/issue-70935-complex-spans.drop_tracking_mir.stderr b/tests/ui/async-await/issue-70935-complex-spans.drop_tracking_mir.stderr
index c636be15a585c..eb9d93e229fb5 100644
--- a/tests/ui/async-await/issue-70935-complex-spans.drop_tracking_mir.stderr
+++ b/tests/ui/async-await/issue-70935-complex-spans.drop_tracking_mir.stderr
@@ -1,18 +1,25 @@
-error[E0277]: `Sender<i32>` cannot be shared between threads safely
- --> $DIR/issue-70935-complex-spans.rs:13:45
+error[E0277]: `*mut ()` cannot be shared between threads safely
+ --> $DIR/issue-70935-complex-spans.rs:18:23
|
-LL | fn foo(tx: std::sync::mpsc::Sender<i32>) -> impl Future + Send {
- | ^^^^^^^^^^^^^^^^^^ `Sender<i32>` cannot be shared between threads safely
+LL | fn foo(x: NotSync) -> impl Future + Send {
+ | ^^^^^^^^^^^^^^^^^^ `*mut ()` cannot be shared between threads safely
|
- = help: the trait `Sync` is not implemented for `Sender<i32>`
- = note: required for `&Sender<i32>` to implement `Send`
+ = help: within `NotSync`, the trait `Sync` is not implemented for `*mut ()`
+note: required because it appears within the type `PhantomData<*mut ()>`
+ --> $SRC_DIR/core/src/marker.rs:LL:COL
+note: required because it appears within the type `NotSync`
+ --> $DIR/issue-70935-complex-spans.rs:12:8
+ |
+LL | struct NotSync(PhantomData<*mut ()>);
+ | ^^^^^^^
+ = note: required for `&NotSync` to implement `Send`
note: required because it's used within this closure
- --> $DIR/issue-70935-complex-spans.rs:17:13
+ --> $DIR/issue-70935-complex-spans.rs:22:13
|
-LL | baz(|| async{
+LL | baz(|| async {
| ^^
note: required because it's used within this `async fn` body
- --> $DIR/issue-70935-complex-spans.rs:10:67
+ --> $DIR/issue-70935-complex-spans.rs:15:67
|
LL | async fn baz<T>(_c: impl FnMut() -> T) where T: Future<Output=()> {
| ___________________________________________________________________^
@@ -20,11 +27,11 @@ LL | | }
| |_^
= note: required because it captures the following types: `impl Future<Output = ()>`
note: required because it's used within this `async` block
- --> $DIR/issue-70935-complex-spans.rs:16:5
+ --> $DIR/issue-70935-complex-spans.rs:21:5
|
LL | / async move {
-LL | | baz(|| async{
-LL | | foo(tx.clone());
+LL | | baz(|| async {
+LL | | foo(x.clone());
LL | | }).await;
LL | | }
| |_____^
diff --git a/tests/ui/async-await/issue-70935-complex-spans.no_drop_tracking.stderr b/tests/ui/async-await/issue-70935-complex-spans.no_drop_tracking.stderr
index ef0e182e5156f..d8ef6a5eedb7d 100644
--- a/tests/ui/async-await/issue-70935-complex-spans.no_drop_tracking.stderr
+++ b/tests/ui/async-await/issue-70935-complex-spans.no_drop_tracking.stderr
@@ -1,21 +1,21 @@
error: future cannot be sent between threads safely
- --> $DIR/issue-70935-complex-spans.rs:13:45
+ --> $DIR/issue-70935-complex-spans.rs:18:23
|
-LL | fn foo(tx: std::sync::mpsc::Sender<i32>) -> impl Future + Send {
- | ^^^^^^^^^^^^^^^^^^ future created by async block is not `Send`
+LL | fn foo(x: NotSync) -> impl Future + Send {
+ | ^^^^^^^^^^^^^^^^^^ future created by async block is not `Send`
|
- = help: the trait `Sync` is not implemented for `Sender<i32>`
+ = help: within `NotSync`, the trait `Sync` is not implemented for `*mut ()`
note: future is not `Send` as this value is used across an await
- --> $DIR/issue-70935-complex-spans.rs:19:12
+ --> $DIR/issue-70935-complex-spans.rs:24:12
|
-LL | baz(|| async{
+LL | baz(|| async {
| _____________-
-LL | | foo(tx.clone());
+LL | | foo(x.clone());
LL | | }).await;
| | - ^^^^^- the value is later dropped here
| | | |
| |_________| await occurs here, with the value maybe used later
- | has type `[closure@$DIR/issue-70935-complex-spans.rs:17:13: 17:15]` which is not `Send`
+ | has type `[closure@$DIR/issue-70935-complex-spans.rs:22:13: 22:15]` which is not `Send`
error: aborting due to previous error
diff --git a/tests/ui/async-await/issue-70935-complex-spans.rs b/tests/ui/async-await/issue-70935-complex-spans.rs
index 78625bd393d25..9ebde1d397733 100644
--- a/tests/ui/async-await/issue-70935-complex-spans.rs
+++ b/tests/ui/async-await/issue-70935-complex-spans.rs
@@ -6,16 +6,21 @@
// with newlines which lead complex diagnostics.
use std::future::Future;
+use std::marker::PhantomData;
+
+#[derive(Clone)]
+struct NotSync(PhantomData<*mut ()>);
+unsafe impl Send for NotSync {}
async fn baz<T>(_c: impl FnMut() -> T) where T: Future<Output=()> {
}
-fn foo(tx: std::sync::mpsc::Sender<i32>) -> impl Future + Send {
+fn foo(x: NotSync) -> impl Future + Send {
//[no_drop_tracking]~^ ERROR future cannot be sent between threads safely
- //[drop_tracking,drop_tracking_mir]~^^ ERROR `Sender<i32>` cannot be shared between threads
+ //[drop_tracking,drop_tracking_mir]~^^ ERROR `*mut ()` cannot be shared between threads
async move {
- baz(|| async{
- foo(tx.clone());
+ baz(|| async {
+ foo(x.clone());
}).await;
}
}
@@ -24,6 +29,6 @@ fn bar(_s: impl Future + Send) {
}
fn main() {
- let (tx, _rx) = std::sync::mpsc::channel();
- bar(foo(tx));
+ let x = NotSync(PhantomData);
+ bar(foo(x));
}
diff --git a/tests/ui/closures/closure-move-sync.rs b/tests/ui/closures/closure-move-sync.rs
index ea2d1434c4ae7..3ee2b35f59fcc 100644
--- a/tests/ui/closures/closure-move-sync.rs
+++ b/tests/ui/closures/closure-move-sync.rs
@@ -13,10 +13,4 @@ fn bar() {
t.join().unwrap();
}
-fn foo() {
- let (tx, _rx) = channel();
- thread::spawn(|| tx.send(()).unwrap());
- //~^ ERROR `Sender<()>` cannot be shared between threads safely
-}
-
fn main() {}
diff --git a/tests/ui/closures/closure-move-sync.stderr b/tests/ui/closures/closure-move-sync.stderr
index 64e3b51ea713b..aee903ac9504a 100644
--- a/tests/ui/closures/closure-move-sync.stderr
+++ b/tests/ui/closures/closure-move-sync.stderr
@@ -20,24 +20,6 @@ LL | let t = thread::spawn(|| {
note: required by a bound in `spawn`
--> $SRC_DIR/std/src/thread/mod.rs:LL:COL
-error[E0277]: `Sender<()>` cannot be shared between threads safely
- --> $DIR/closure-move-sync.rs:18:19
- |
-LL | thread::spawn(|| tx.send(()).unwrap());
- | ------------- ^^^^^^^^^^^^^^^^^^^^^^^ `Sender<()>` cannot be shared between threads safely
- | |
- | required by a bound introduced by this call
- |
- = help: the trait `Sync` is not implemented for `Sender<()>`
- = note: required for `&Sender<()>` to implement `Send`
-note: required because it's used within this closure
- --> $DIR/closure-move-sync.rs:18:19
- |
-LL | thread::spawn(|| tx.send(()).unwrap());
- | ^^
-note: required by a bound in `spawn`
- --> $SRC_DIR/std/src/thread/mod.rs:LL:COL
-
-error: aborting due to 2 previous errors
+error: aborting due to previous error
For more information about this error, try `rustc --explain E0277`.
diff --git a/tests/ui/stdlib-unit-tests/not-sync.rs b/tests/ui/stdlib-unit-tests/not-sync.rs
index f4648994fa918..e9395ae9e81aa 100644
--- a/tests/ui/stdlib-unit-tests/not-sync.rs
+++ b/tests/ui/stdlib-unit-tests/not-sync.rs
@@ -17,6 +17,4 @@ fn main() {
test::<Receiver<i32>>();
//~^ ERROR `std::sync::mpsc::Receiver<i32>` cannot be shared between threads safely [E0277]
- test::<Sender<i32>>();
- //~^ ERROR `Sender<i32>` cannot be shared between threads safely [E0277]
}
diff --git a/tests/ui/stdlib-unit-tests/not-sync.stderr b/tests/ui/stdlib-unit-tests/not-sync.stderr
index 4e34e10e37789..b9a266e4eb9b9 100644
--- a/tests/ui/stdlib-unit-tests/not-sync.stderr
+++ b/tests/ui/stdlib-unit-tests/not-sync.stderr
@@ -65,19 +65,6 @@ note: required by a bound in `test`
LL | fn test<T: Sync>() {}
| ^^^^ required by this bound in `test`
-error[E0277]: `Sender<i32>` cannot be shared between threads safely
- --> $DIR/not-sync.rs:20:12
- |
-LL | test::<Sender<i32>>();
- | ^^^^^^^^^^^ `Sender<i32>` cannot be shared between threads safely
- |
- = help: the trait `Sync` is not implemented for `Sender<i32>`
-note: required by a bound in `test`
- --> $DIR/not-sync.rs:5:12
- |
-LL | fn test<T: Sync>() {}
- | ^^^^ required by this bound in `test`
-
-error: aborting due to 6 previous errors
+error: aborting due to 5 previous errors
For more information about this error, try `rustc --explain E0277`.