From d9d35cc6967501818863adcb556991357098557d Mon Sep 17 00:00:00 2001
From: Tim Diekmann <tim.diekmann@3dvision.de>
Date: Wed, 25 Mar 2020 18:30:14 +0100
Subject: [PATCH] Add comment to `AllocRef` implementation for `System`

---
 src/libstd/alloc.rs | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/libstd/alloc.rs b/src/libstd/alloc.rs
index f295565bec3..6e8ac7c9036 100644
--- a/src/libstd/alloc.rs
+++ b/src/libstd/alloc.rs
@@ -134,6 +134,8 @@
 #[derive(Debug, Default, Copy, Clone)]
 pub struct System;
 
+// The AllocRef impl checks the layout size to be non-zero and forwards to the GlobalAlloc impl,
+// which is in `std::sys::*::alloc`.
 #[unstable(feature = "allocator_api", issue = "32838")]
 unsafe impl AllocRef for System {
     #[inline]
-- 
2.44.0