From 59bbbe78e2ddf6f5c823372890b928fe19e41ac3 Mon Sep 17 00:00:00 2001
From: Oli Scherer <git-spam-no-reply9815368754983@oli-obk.de>
Date: Fri, 13 May 2022 09:30:09 +0000
Subject: [PATCH] Avoid invoking the full `eq` infrastructure when all we want
 is to check a discriminant

---
 compiler/rustc_middle/src/traits/mod.rs | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/compiler/rustc_middle/src/traits/mod.rs b/compiler/rustc_middle/src/traits/mod.rs
index 8072dd16ae8..dcd457957a8 100644
--- a/compiler/rustc_middle/src/traits/mod.rs
+++ b/compiler/rustc_middle/src/traits/mod.rs
@@ -206,7 +206,9 @@ pub struct InternedObligationCauseCode<'tcx> {
 impl<'tcx> From<ObligationCauseCode<'tcx>> for InternedObligationCauseCode<'tcx> {
     #[inline(always)]
     fn from(code: ObligationCauseCode<'tcx>) -> Self {
-        Self { code: if code == MISC_OBLIGATION_CAUSE_CODE { None } else { Some(Lrc::new(code)) } }
+        Self {
+            code: if let MISC_OBLIGATION_CAUSE_CODE = code { None } else { Some(Lrc::new(code)) },
+        }
     }
 }