From 8016940ef41b1245aecf9eb19c02b85f45dcd133 Mon Sep 17 00:00:00 2001
From: Zalathar <Zalathar@users.noreply.github.com>
Date: Mon, 24 Jun 2024 12:50:04 +1000
Subject: [PATCH] Tweak a confusing comment in `create_match_candidates`
---
compiler/rustc_mir_build/src/build/matches/mod.rs | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)
diff --git a/compiler/rustc_mir_build/src/build/matches/mod.rs b/compiler/rustc_mir_build/src/build/matches/mod.rs
index 68244136d1adf..350b00db7fddf 100644
--- a/compiler/rustc_mir_build/src/build/matches/mod.rs
+++ b/compiler/rustc_mir_build/src/build/matches/mod.rs
@@ -358,8 +358,11 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
where
'a: 'pat,
{
- // Assemble a list of candidates: there is one candidate per pattern,
- // which means there may be more than one candidate *per arm*.
+ // Assemble the initial list of candidates. These top-level candidates
+ // are 1:1 with the original match arms, but other parts of match
+ // lowering also introduce subcandidates (for subpatterns), and will
+ // also flatten candidates in some cases. So in general a list of
+ // candidates does _not_ necessarily correspond to a list of arms.
arms.iter()
.copied()
.map(|arm| {