From de39a4f6218fac9d0b9d09a928613b4aa2407a31 Mon Sep 17 00:00:00 2001
From: Stein Somers <git@steinsomers.be>
Date: Thu, 9 Apr 2020 20:19:18 +0200
Subject: [PATCH] Respect the comment: no root unless the borrow type is `Mut`

---
 src/liballoc/collections/btree/node.rs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/liballoc/collections/btree/node.rs b/src/liballoc/collections/btree/node.rs
index bc4e2711670..84d34db2d45 100644
--- a/src/liballoc/collections/btree/node.rs
+++ b/src/liballoc/collections/btree/node.rs
@@ -161,7 +161,7 @@ impl<K, V> Root<K, V> {
         NodeRef {
             height: self.height,
             node: self.node.as_ptr(),
-            root: self as *const _ as *mut _,
+            root: ptr::null(),
             _marker: PhantomData,
         }
     }
@@ -179,7 +179,7 @@ impl<K, V> Root<K, V> {
         NodeRef {
             height: self.height,
             node: self.node.as_ptr(),
-            root: ptr::null_mut(), // FIXME: Is there anything better to do here?
+            root: ptr::null(),
             _marker: PhantomData,
         }
     }