From 29621ba28876696a8dd01d746c49f3affc843c49 Mon Sep 17 00:00:00 2001
From: Callum Leslie <git@cleslie.uk>
Date: Wed, 15 Feb 2023 16:22:08 +0000
Subject: [PATCH] clarify correctness of `black_box`

---
 library/core/src/hint.rs | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/library/core/src/hint.rs b/library/core/src/hint.rs
index 5a76e866923..ee13dae60b1 100644
--- a/library/core/src/hint.rs
+++ b/library/core/src/hint.rs
@@ -216,7 +216,8 @@ pub fn spin_loop() {
 ///
 /// Note however, that `black_box` is only (and can only be) provided on a "best-effort" basis. The
 /// extent to which it can block optimisations may vary depending upon the platform and code-gen
-/// backend used. Programs cannot rely on `black_box` for *correctness* in any way.
+/// backend used. Programs cannot rely on `black_box` for *correctness*, beyond it behaving as the
+/// identity function.
 ///
 /// [`std::convert::identity`]: crate::convert::identity
 ///