Fix parameter order for allocator

Author: TimDiekmann

library/alloc/src/rc.rs

@@ -274,12 +274,12 @@ use crate::vec::Vec;
 #[cfg(test)]
 mod tests;
 
-struct RcBoxMetadata {
+struct RcMetadata {
     strong: Cell<usize>,
     weak: Cell<usize>,
 }
 
-impl RcBoxMetadata {
+impl RcMetadata {
     // There is an implicit weak pointer owned by all the strong
     // pointers, which ensures that the weak destructor never frees
     // the allocation while the strong destructor is running, even
@@ -300,7 +300,7 @@ impl RcBoxMetadata {
 // inner types.
 #[repr(C)]
 struct RcBox<T: ?Sized> {
-    meta: RcBoxMetadata,
+    meta: RcMetadata,
     value: T,
 }
 
@@ -363,7 +363,7 @@ impl<T> Rc<T> {
     /// ```
     #[stable(feature = "rust1", since = "1.0.0")]
     pub fn new(value: T) -> Rc<T> {
-        Self::from_inner(Box::leak(box RcBox { meta: RcBoxMetadata::new_strong(), value }).into())
+        Self::from_inner(Box::leak(box RcBox { meta: RcMetadata::new_strong(), value }).into())
     }
 
     /// Constructs a new `Rc<T>` using a weak reference to itself. Attempting
@@ -395,7 +395,7 @@ impl<T> Rc<T> {
         // Construct the inner in the "uninitialized" state with a single
         // weak reference.
         let uninit_ptr: NonNull<_> = Box::leak(box RcBox {
-            meta: RcBoxMetadata::new_weak(),
+            meta: RcMetadata::new_weak(),
             value: mem::MaybeUninit::<T>::uninit(),
         })
         .into();
@@ -510,7 +510,7 @@ impl<T> Rc<T> {
         // the allocation while the strong destructor is running, even
         // if the weak pointer is stored inside the strong one.
         Ok(Self::from_inner(
-            Box::leak(Box::try_new(RcBox { meta: RcBoxMetadata::new_strong(), value })?).into(),
+            Box::leak(Box::try_new(RcBox { meta: RcMetadata::new_strong(), value })?).into(),
         ))
     }
 
@@ -2479,7 +2479,7 @@ impl<T: ?Sized> AsRef<T> for Rc<T> {
 #[stable(feature = "pin", since = "1.33.0")]
 impl<T: ?Sized> Unpin for Rc<T> {}
 
-type RcAllocator = PrefixAllocator<RcBoxMetadata, Global>;
+type RcAllocator = PrefixAllocator<Global, RcMetadata>;
 
 /// Get the offset within an `RcBox` for the payload behind a pointer.
 ///

library/alloc/src/sync.rs

@@ -297,7 +297,7 @@ impl<T: ?Sized + fmt::Debug> fmt::Debug for Weak<T> {
     }
 }
 
-struct ArcInnerMetadata {
+struct ArcMetadata {
     strong: atomic::AtomicUsize,
 
     // the value usize::MAX acts as a sentinel for temporarily "locking" the
@@ -306,7 +306,7 @@ struct ArcInnerMetadata {
     weak: atomic::AtomicUsize,
 }
 
-impl ArcInnerMetadata {
+impl ArcMetadata {
     #[inline]
     fn new_strong() -> Self {
         Self { strong: atomic::AtomicUsize::new(1), weak: atomic::AtomicUsize::new(1) }
@@ -323,7 +323,7 @@ impl ArcInnerMetadata {
 // inner types.
 #[repr(C)]
 struct ArcInner<T: ?Sized> {
-    meta: ArcInnerMetadata,
+    meta: ArcMetadata,
     data: T,
 }
 
@@ -343,7 +343,7 @@ impl<T> Arc<T> {
     #[inline]
     #[stable(feature = "rust1", since = "1.0.0")]
     pub fn new(data: T) -> Arc<T> {
-        let x: Box<_> = box ArcInner { meta: ArcInnerMetadata::new_strong(), data };
+        let x: Box<_> = box ArcInner { meta: ArcMetadata::new_strong(), data };
         Self::from_inner(Box::leak(x).into())
     }
 
@@ -373,7 +373,7 @@ impl<T> Arc<T> {
         // Construct the inner in the "uninitialized" state with a single
         // weak reference.
         let uninit_ptr: NonNull<_> = Box::leak(box ArcInner {
-            meta: ArcInnerMetadata::new_weak(),
+            meta: ArcMetadata::new_weak(),
             data: mem::MaybeUninit::<T>::uninit(),
         })
         .into();
@@ -503,7 +503,7 @@ impl<T> Arc<T> {
     #[unstable(feature = "allocator_api", issue = "32838")]
     #[inline]
     pub fn try_new(data: T) -> Result<Arc<T>, AllocError> {
-        let x: Box<_> = Box::try_new(ArcInner { meta: ArcInnerMetadata::new_strong(), data })?;
+        let x: Box<_> = Box::try_new(ArcInner { meta: ArcMetadata::new_strong(), data })?;
         Ok(Self::from_inner(Box::leak(x).into()))
     }
 
@@ -2521,7 +2521,7 @@ impl<T: ?Sized> AsRef<T> for Arc<T> {
 #[stable(feature = "pin", since = "1.33.0")]
 impl<T: ?Sized> Unpin for Arc<T> {}
 
-type ArcAllocator = PrefixAllocator<ArcInnerMetadata, Global>;
+type ArcAllocator = PrefixAllocator<Global, ArcMetadata>;
 
 /// Get the offset within an `ArcInner` for the payload behind a pointer.
 ///