From bd604750aefef6638cb781b0c7711cfd95e24043 Mon Sep 17 00:00:00 2001
From: Alan Egerton <eggyal@gmail.com>
Date: Mon, 20 Jun 2022 19:03:37 +0100
Subject: [PATCH] `try_fold_unevaluated` for infallible folders

#97447 added folding of unevaluated constants, but did not include an override of the default (fallible) operation in the blanket impl of `FallibleTypeFolder` for infallible folders.  Here we provide that missing override.

r? @nnethercote
---
 compiler/rustc_middle/src/ty/fold.rs | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/compiler/rustc_middle/src/ty/fold.rs b/compiler/rustc_middle/src/ty/fold.rs
index 99aa182f3a6a6..31b8fa1ce956f 100644
--- a/compiler/rustc_middle/src/ty/fold.rs
+++ b/compiler/rustc_middle/src/ty/fold.rs
@@ -371,6 +371,13 @@ where
         Ok(self.fold_const(c))
     }
 
+    fn try_fold_unevaluated(
+        &mut self,
+        c: ty::Unevaluated<'tcx>,
+    ) -> Result<ty::Unevaluated<'tcx>, Self::Error> {
+        Ok(self.fold_unevaluated(c))
+    }
+
     fn try_fold_predicate(
         &mut self,
         p: ty::Predicate<'tcx>,