Use portable-atomic when necessary.

Author: reitermarkus

src/pool/arc.rs

@@ -72,9 +72,15 @@ use core::{
     hash::{Hash, Hasher},
     mem::{ManuallyDrop, MaybeUninit},
     ops, ptr,
-    sync::atomic::{self, AtomicUsize, Ordering},
 };
 
+#[cfg(not(feature = "portable-atomic"))]
+use core::sync::atomic;
+#[cfg(feature = "portable-atomic")]
+use portable_atomic as atomic;
+
+use atomic::{AtomicUsize, Ordering};
+
 use super::treiber::{NonNullPtr, Stack, UnionNode};
 
 /// Creates a new `ArcPool` singleton with the given `$name` that manages the specified `$data_type`

src/pool/treiber/cas.rs

@@ -1,10 +1,12 @@
-use core::{marker::PhantomData, ptr::NonNull, sync::atomic::Ordering};
+use core::{marker::PhantomData, ptr::NonNull};
 
 #[cfg(not(feature = "portable-atomic"))]
 use core::sync::atomic;
 #[cfg(feature = "portable-atomic")]
 use portable_atomic as atomic;
 
+use atomic::Ordering;
+
 use super::{Node, Stack};
 
 #[cfg(target_pointer_width = "32")]