Rollup merge of #77399 - ssomers:btree_cleanup_5, r=Mark-Simulacrum

JohnTitor · web-flow · commit c820a522ca75 · 2020-10-02T08:25:25.000+09:00
BTreeMap: use Unique::from to avoid a cast where type information exists r? @Mark-Simulacrum
diff --git a/library/alloc/src/collections/btree/node.rs b/library/alloc/src/collections/btree/node.rs
@@ -128,7 +128,7 @@ impl<K, V> BoxedNode<K, V> {
     }
 
     fn from_internal(node: Box<InternalNode<K, V>>) -> Self {
-        BoxedNode { ptr: Box::into_unique(node).cast() }
+        BoxedNode { ptr: Unique::from(&mut Box::leak(node).data) }
     }
 
     unsafe fn from_ptr(ptr: NonNull<LeafNode<K, V>>) -> Self {

Original file line number	Diff line number	Diff line change
`@@ -128,7 +128,7 @@ impl<K, V> BoxedNode<K, V> {`
`128`	`128`	`}`
`129`	`129`
`130`	`130`	`fn from_internal(node: Box<InternalNode<K, V>>) -> Self {`
`131`		`- BoxedNode { ptr: Box::into_unique(node).cast() }`
	`131`	`+ BoxedNode { ptr: Unique::from(&mut Box::leak(node).data) }`
`132`	`132`	`}`
`133`	`133`
`134`	`134`	`unsafe fn from_ptr(ptr: NonNull<LeafNode<K, V>>) -> Self {`