From 6dd2a9f002b2de0c61fbdaf6d88017f28a4211f3 Mon Sep 17 00:00:00 2001
From: Andrew Walbran <qwandor@google.com>
Date: Mon, 20 Mar 2023 14:24:44 +0000
Subject: [PATCH] Mention why we need `extern crate panic_halt`.

---
 src/bare-metal/alloc.md | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/bare-metal/alloc.md b/src/bare-metal/alloc.md
index 63484b82..989bfb65 100644
--- a/src/bare-metal/alloc.md
+++ b/src/bare-metal/alloc.md
@@ -15,5 +15,7 @@ To use `alloc` you must implement a
   allocate regions of up to 2**32 bytes.
 * If any crate in your dependency tree depends on `alloc` then you must have exactly one global
   allocator defined in your binary. Usually this is done in the top-level binary crate.
+* `extern crate panic_halt as _` is necessary to ensure that the `panic_halt` crate is linked in so
+  we get its panic handler.
 
 </details>