From 094ddd7cd7dd189f9ff92c09db2a86af18db8bf4 Mon Sep 17 00:00:00 2001
From: Ian Jackson <ijackson@chiark.greenend.org.uk>
Date: Thu, 17 Feb 2022 11:07:52 +0000
Subject: [PATCH] Add a comment about "&mut [&mut ]"

---
 crates/tor-circmgr/src/mgr.rs | 1 +
 1 file changed, 1 insertion(+)

diff --git a/crates/tor-circmgr/src/mgr.rs b/crates/tor-circmgr/src/mgr.rs
index 1206d590a..f1cc118dd 100644
--- a/crates/tor-circmgr/src/mgr.rs
+++ b/crates/tor-circmgr/src/mgr.rs
@@ -330,6 +330,7 @@ impl<S: AbstractSpec, C: AbstractCirc> OpenEntry<S, C> {
     /// Requires that `ents` is nonempty, and that every element of `ents`
     /// supports `spec`.
     fn find_best<'a>(
+        // we do not mutate `ents`, but to return `&mut Self` we must have a mutable borrow
         ents: &'a mut [&'a mut Self],
         usage: &<S as AbstractSpec>::Usage,
         parallelism: usize,