diff options
Diffstat (limited to 'library/alloc/src/task.rs')
| -rw-r--r-- | library/alloc/src/task.rs | 18 |
1 files changed, 11 insertions, 7 deletions
diff --git a/library/alloc/src/task.rs b/library/alloc/src/task.rs index 736a55700f6..9db4c919505 100644 --- a/library/alloc/src/task.rs +++ b/library/alloc/src/task.rs @@ -2,15 +2,17 @@ //! Types and Traits for working with asynchronous tasks. //! -//! **Note**: This module is only available on platforms that support atomic -//! loads and stores of pointers. This may be detected at compile time using +//! **Note**: Some of the types in this module are only available +//! on platforms that support atomic loads and stores of pointers. +//! This may be detected at compile time using //! `#[cfg(target_has_atomic = "ptr")]`. use core::mem::ManuallyDrop; -use core::task::{LocalWaker, RawWaker, RawWakerVTable, Waker}; - +use core::task::{LocalWaker, RawWaker, RawWakerVTable}; use crate::rc::Rc; -use crate::sync::Arc; + +#[cfg(target_has_atomic = "ptr")] +use core::{task::Waker, sync::Arc}; /// The implementation of waking a task on an executor. /// @@ -74,6 +76,7 @@ use crate::sync::Arc; /// println!("Hi from inside a future!"); /// }); /// ``` +#[cfg(target_has_atomic = "ptr")] #[stable(feature = "wake_trait", since = "1.51.0")] pub trait Wake { /// Wake this task. @@ -92,7 +95,7 @@ pub trait Wake { self.clone().wake(); } } - +#[cfg(target_has_atomic = "ptr")] #[stable(feature = "wake_trait", since = "1.51.0")] impl<W: Wake + Send + Sync + 'static> From<Arc<W>> for Waker { /// Use a `Wake`-able type as a `Waker`. @@ -104,7 +107,7 @@ impl<W: Wake + Send + Sync + 'static> From<Arc<W>> for Waker { unsafe { Waker::from_raw(raw_waker(waker)) } } } - +#[cfg(target_has_atomic = "ptr")] #[stable(feature = "wake_trait", since = "1.51.0")] impl<W: Wake + Send + Sync + 'static> From<Arc<W>> for RawWaker { /// Use a `Wake`-able type as a `RawWaker`. @@ -120,6 +123,7 @@ impl<W: Wake + Send + Sync + 'static> From<Arc<W>> for RawWaker { // the safety of `From<Arc<W>> for Waker` does not depend on the correct // trait dispatch - instead both impls call this function directly and // explicitly. +#[cfg(target_has_atomic = "ptr")] #[inline(always)] fn raw_waker<W: Wake + Send + Sync + 'static>(waker: Arc<W>) -> RawWaker { // Increment the reference count of the arc to clone it. |
