From a74eba4ad56fe3138a23c471ad00d0e906bc3809 Mon Sep 17 00:00:00 2001
From: Deadbeef <ent3rm4n@gmail.com>
Date: Fri, 23 Sep 2022 18:07:36 +0000
Subject: [PATCH] Make `ManuallyDrop` satisfy `~const Destruct`

---
 .../rustc_trait_selection/src/traits/select/confirmation.rs    | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/compiler/rustc_trait_selection/src/traits/select/confirmation.rs b/compiler/rustc_trait_selection/src/traits/select/confirmation.rs
index e08f03a270c..27fbfb6dd21 100644
--- a/compiler/rustc_trait_selection/src/traits/select/confirmation.rs
+++ b/compiler/rustc_trait_selection/src/traits/select/confirmation.rs
@@ -1224,6 +1224,9 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
                 | ty::Never
                 | ty::Foreign(_) => {}
 
+                // `ManuallyDrop` is trivially drop
+                ty::Adt(def, _) if Some(def.did()) == tcx.lang_items().manually_drop() => {}
+
                 // These types are built-in, so we can fast-track by registering
                 // nested predicates for their constituent type(s)
                 ty::Array(ty, _) | ty::Slice(ty) => {