diff options
Diffstat (limited to '')
| -rw-r--r-- | library/alloc/src/collections/btree/node.rs | 22 |
1 files changed, 12 insertions, 10 deletions
diff --git a/library/alloc/src/collections/btree/node.rs b/library/alloc/src/collections/btree/node.rs index d831161bc..da766b67a 100644 --- a/library/alloc/src/collections/btree/node.rs +++ b/library/alloc/src/collections/btree/node.rs @@ -206,9 +206,9 @@ impl<'a, K: 'a, V: 'a, Type> Clone for NodeRef<marker::Immut<'a>, K, V, Type> { unsafe impl<BorrowType, K: Sync, V: Sync, Type> Sync for NodeRef<BorrowType, K, V, Type> {} -unsafe impl<'a, K: Sync + 'a, V: Sync + 'a, Type> Send for NodeRef<marker::Immut<'a>, K, V, Type> {} -unsafe impl<'a, K: Send + 'a, V: Send + 'a, Type> Send for NodeRef<marker::Mut<'a>, K, V, Type> {} -unsafe impl<'a, K: Send + 'a, V: Send + 'a, Type> Send for NodeRef<marker::ValMut<'a>, K, V, Type> {} +unsafe impl<K: Sync, V: Sync, Type> Send for NodeRef<marker::Immut<'_>, K, V, Type> {} +unsafe impl<K: Send, V: Send, Type> Send for NodeRef<marker::Mut<'_>, K, V, Type> {} +unsafe impl<K: Send, V: Send, Type> Send for NodeRef<marker::ValMut<'_>, K, V, Type> {} unsafe impl<K: Send, V: Send, Type> Send for NodeRef<marker::Owned, K, V, Type> {} unsafe impl<K: Send, V: Send, Type> Send for NodeRef<marker::Dying, K, V, Type> {} @@ -318,7 +318,7 @@ impl<BorrowType: marker::BorrowType, K, V, Type> NodeRef<BorrowType, K, V, Type> pub fn ascend( self, ) -> Result<Handle<NodeRef<BorrowType, K, V, marker::Internal>, marker::Edge>, Self> { - assert!(BorrowType::PERMITS_TRAVERSAL); + let _ = BorrowType::TRAVERSAL_PERMIT; // We need to use raw pointers to nodes because, if BorrowType is marker::ValMut, // there might be outstanding mutable references to values that we must not invalidate. let leaf_ptr: *const _ = Self::as_leaf_ptr(&self); @@ -1003,7 +1003,7 @@ impl<BorrowType: marker::BorrowType, K, V> /// `edge.descend().ascend().unwrap()` and `node.ascend().unwrap().descend()` should /// both, upon success, do nothing. pub fn descend(self) -> NodeRef<BorrowType, K, V, marker::LeafOrInternal> { - assert!(BorrowType::PERMITS_TRAVERSAL); + let _ = BorrowType::TRAVERSAL_PERMIT; // We need to use raw pointers to nodes because, if BorrowType is // marker::ValMut, there might be outstanding mutable references to // values that we must not invalidate. There's no worry accessing the @@ -1666,15 +1666,17 @@ pub mod marker { pub struct ValMut<'a>(PhantomData<&'a mut ()>); pub trait BorrowType { - // Whether node references of this borrow type allow traversing - // to other nodes in the tree. - const PERMITS_TRAVERSAL: bool = true; + // If node references of this borrow type allow traversing to other + // nodes in the tree, this constant can be evaluated. Thus reading it + // serves as a compile-time assertion. + const TRAVERSAL_PERMIT: () = (); } impl BorrowType for Owned { - // Traversal isn't needed, it happens using the result of `borrow_mut`. + // Reject evaluation, because traversal isn't needed. Instead traversal + // happens using the result of `borrow_mut`. // By disabling traversal, and only creating new references to roots, // we know that every reference of the `Owned` type is to a root node. - const PERMITS_TRAVERSAL: bool = false; + const TRAVERSAL_PERMIT: () = panic!(); } impl BorrowType for Dying {} impl<'a> BorrowType for Immut<'a> {} |