From 64839ee00ab4076d797901ddea55f2613c5b75b5 Mon Sep 17 00:00:00 2001
From: Mara Bos <m-ou.se@m-ou.se>
Date: Thu, 8 Oct 2020 23:51:56 +0200
Subject: [PATCH 1/6] Add Pin::new_static.
---
library/core/src/pin.rs | 13 +++++++++++++
1 file changed, 13 insertions(+)
diff --git a/library/core/src/pin.rs b/library/core/src/pin.rs
index 9f0284d5d9542..cc93f0fa5fc6f 100644
--- a/library/core/src/pin.rs
+++ b/library/core/src/pin.rs
@@ -781,6 +781,19 @@ impl<'a, T: ?Sized> Pin<&'a mut T> {
}
}
+impl<T: ?Sized> Pin<&'static T> {
+ /// Get a pinned reference from a static reference.
+ ///
+ /// This is safe, because the `'static` lifetime guarantees the data will
+ /// never be moved.
+ #[unstable(feature = "pin_static_ref", issue = "none")]
+ pub fn new_static(r: &'static T) -> Pin<&'static T> {
+ // SAFETY: The 'static lifetime guarantees the data will not be
+ // moved/invalidated until it gets dropped (which is never).
+ unsafe { Pin::new_unchecked(r) }
+ }
+}
+
#[stable(feature = "pin", since = "1.33.0")]
impl<P: Deref> Deref for Pin<P> {
type Target = P::Target;
From 390883e888c580d054ab4a2584c851aba50865e9 Mon Sep 17 00:00:00 2001
From: Mara Bos <m-ou.se@m-ou.se>
Date: Fri, 9 Oct 2020 00:06:39 +0200
Subject: [PATCH 2/6] Make Pin::new_static const.
---
library/core/src/pin.rs | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/library/core/src/pin.rs b/library/core/src/pin.rs
index cc93f0fa5fc6f..3f058124d2bde 100644
--- a/library/core/src/pin.rs
+++ b/library/core/src/pin.rs
@@ -787,7 +787,8 @@ impl<T: ?Sized> Pin<&'static T> {
/// This is safe, because the `'static` lifetime guarantees the data will
/// never be moved.
#[unstable(feature = "pin_static_ref", issue = "none")]
- pub fn new_static(r: &'static T) -> Pin<&'static T> {
+ #[rustc_const_unstable(feature = "const_pin", issue = "76654")]
+ pub const fn new_static(r: &'static T) -> Pin<&'static T> {
// SAFETY: The 'static lifetime guarantees the data will not be
// moved/invalidated until it gets dropped (which is never).
unsafe { Pin::new_unchecked(r) }
From 104c0f0194177442ff16cf14907a96d2f8d200dd Mon Sep 17 00:00:00 2001
From: Mara Bos <m-ou.se@m-ou.se>
Date: Mon, 12 Oct 2020 20:00:44 +0200
Subject: [PATCH 3/6] Rename Pin::new_static to Pin::static_ref.
---
library/core/src/pin.rs | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/library/core/src/pin.rs b/library/core/src/pin.rs
index 3f058124d2bde..9e2d64a866fbb 100644
--- a/library/core/src/pin.rs
+++ b/library/core/src/pin.rs
@@ -788,7 +788,7 @@ impl<T: ?Sized> Pin<&'static T> {
/// never be moved.
#[unstable(feature = "pin_static_ref", issue = "none")]
#[rustc_const_unstable(feature = "const_pin", issue = "76654")]
- pub const fn new_static(r: &'static T) -> Pin<&'static T> {
+ pub const fn static_ref(r: &'static T) -> Pin<&'static T> {
// SAFETY: The 'static lifetime guarantees the data will not be
// moved/invalidated until it gets dropped (which is never).
unsafe { Pin::new_unchecked(r) }
From 2c71f682d74d13ae6673dc701a9bb3a0562f57c0 Mon Sep 17 00:00:00 2001
From: Mara Bos <m-ou.se@m-ou.se>
Date: Mon, 12 Oct 2020 20:00:56 +0200
Subject: [PATCH 4/6] Add Pin::static_mut.
---
library/core/src/pin.rs | 14 ++++++++++++++
1 file changed, 14 insertions(+)
diff --git a/library/core/src/pin.rs b/library/core/src/pin.rs
index 9e2d64a866fbb..b27167a7e7c66 100644
--- a/library/core/src/pin.rs
+++ b/library/core/src/pin.rs
@@ -795,6 +795,20 @@ impl<T: ?Sized> Pin<&'static T> {
}
}
+impl<T: ?Sized> Pin<&'static T> {
+ /// Get a pinned mutable reference from a static mutable reference.
+ ///
+ /// This is safe, because the `'static` lifetime guarantees the data will
+ /// never be moved.
+ #[unstable(feature = "pin_static_ref", issue = "none")]
+ #[rustc_const_unstable(feature = "const_pin", issue = "76654")]
+ pub const fn static_mut(r: &'static mut T) -> Pin<&'static mut T> {
+ // SAFETY: The 'static lifetime guarantees the data will not be
+ // moved/invalidated until it gets dropped (which is never).
+ unsafe { Pin::new_unchecked(r) }
+ }
+}
+
#[stable(feature = "pin", since = "1.33.0")]
impl<P: Deref> Deref for Pin<P> {
type Target = P::Target;
From f83446b836900ce9afbaa0816a5b4feda654b51e Mon Sep 17 00:00:00 2001
From: Mara Bos <m-ou.se@m-ou.se>
Date: Tue, 13 Oct 2020 13:13:09 +0200
Subject: [PATCH 5/6] Reword safety guarantee of Pin::static_{ref,mut}.
Co-authored-by: Peter Todd <pete@petertodd.org>
---
library/core/src/pin.rs | 12 ++++++------
1 file changed, 6 insertions(+), 6 deletions(-)
diff --git a/library/core/src/pin.rs b/library/core/src/pin.rs
index b27167a7e7c66..633e96eb7d811 100644
--- a/library/core/src/pin.rs
+++ b/library/core/src/pin.rs
@@ -784,12 +784,12 @@ impl<'a, T: ?Sized> Pin<&'a mut T> {
impl<T: ?Sized> Pin<&'static T> {
/// Get a pinned reference from a static reference.
///
- /// This is safe, because the `'static` lifetime guarantees the data will
- /// never be moved.
+ /// This is safe, because `T` is borrowed for the `'static` lifetime, which
+ /// never ends.
#[unstable(feature = "pin_static_ref", issue = "none")]
#[rustc_const_unstable(feature = "const_pin", issue = "76654")]
pub const fn static_ref(r: &'static T) -> Pin<&'static T> {
- // SAFETY: The 'static lifetime guarantees the data will not be
+ // SAFETY: The 'static borrow guarantees the data will not be
// moved/invalidated until it gets dropped (which is never).
unsafe { Pin::new_unchecked(r) }
}
@@ -798,12 +798,12 @@ impl<T: ?Sized> Pin<&'static T> {
impl<T: ?Sized> Pin<&'static T> {
/// Get a pinned mutable reference from a static mutable reference.
///
- /// This is safe, because the `'static` lifetime guarantees the data will
- /// never be moved.
+ /// This is safe, because `T` is borrowed for the `'static` lifetime, which
+ /// never ends.
#[unstable(feature = "pin_static_ref", issue = "none")]
#[rustc_const_unstable(feature = "const_pin", issue = "76654")]
pub const fn static_mut(r: &'static mut T) -> Pin<&'static mut T> {
- // SAFETY: The 'static lifetime guarantees the data will not be
+ // SAFETY: The 'static borrow guarantees the data will not be
// moved/invalidated until it gets dropped (which is never).
unsafe { Pin::new_unchecked(r) }
}
From df95dcebf5f98cefdc60c9b9d818fb285ac07d5b Mon Sep 17 00:00:00 2001
From: Mara Bos <m-ou.se@m-ou.se>
Date: Thu, 15 Oct 2020 21:45:09 +0200
Subject: [PATCH 6/6] Add missing `mut`.
Co-authored-by: David Tolnay <dtolnay@gmail.com>
---
library/core/src/pin.rs | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/library/core/src/pin.rs b/library/core/src/pin.rs
index 633e96eb7d811..b73cd046e5a65 100644
--- a/library/core/src/pin.rs
+++ b/library/core/src/pin.rs
@@ -795,7 +795,7 @@ impl<T: ?Sized> Pin<&'static T> {
}
}
-impl<T: ?Sized> Pin<&'static T> {
+impl<T: ?Sized> Pin<&'static mut T> {
/// Get a pinned mutable reference from a static mutable reference.
///
/// This is safe, because `T` is borrowed for the `'static` lifetime, which