From 58a90de9adfac7cc26fe178b3f736153b756a515 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?D=C3=A1niel=20Buga?= <bugadani@gmail.com>
Date: Fri, 22 Jan 2021 08:14:25 +0100
Subject: [PATCH] No peeking

---
 compiler/rustc_typeck/src/check/check.rs | 8 +-------
 1 file changed, 1 insertion(+), 7 deletions(-)

diff --git a/compiler/rustc_typeck/src/check/check.rs b/compiler/rustc_typeck/src/check/check.rs
index 279c4422fe12..e89a063598ab 100644
--- a/compiler/rustc_typeck/src/check/check.rs
+++ b/compiler/rustc_typeck/src/check/check.rs
@@ -854,13 +854,7 @@ pub(super) fn check_specialization_validity<'tcx>(
             } else {
                 Some((parent, parent.item(tcx, trait_item.ident, kind, trait_def.def_id)))
             }
-        })
-        .peekable();
-
-    if ancestor_impls.peek().is_none() {
-        // No parent, nothing to specialize.
-        return;
-    }
+        });
 
     let opt_result = ancestor_impls.find_map(|(parent_impl, parent_item)| {
         match parent_item {