From e26692d559c3b564a3efdd5b6db316c0c67fb52e Mon Sep 17 00:00:00 2001
From: Nicholas Nethercote <n.nethercote@gmail.com>
Date: Tue, 3 Sep 2024 11:00:15 +1000
Subject: [PATCH] Add a useful comment.

---
 compiler/rustc_mir_transform/src/large_enums.rs | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/compiler/rustc_mir_transform/src/large_enums.rs b/compiler/rustc_mir_transform/src/large_enums.rs
index 8a33849f20e..3e263aa4067 100644
--- a/compiler/rustc_mir_transform/src/large_enums.rs
+++ b/compiler/rustc_mir_transform/src/large_enums.rs
@@ -244,6 +244,8 @@ fn candidate<'tcx>(
         let ptr_sized_int = data_layout.ptr_sized_integer();
         let target_bytes = ptr_sized_int.size().bytes() as usize;
         let mut data = vec![0; target_bytes * num_discrs];
+
+        // We use a macro because `$bytes` can be u32 or u64.
         macro_rules! encode_store {
             ($curr_idx: expr, $endian: expr, $bytes: expr) => {
                 let bytes = match $endian {