From a3ee65f87e2138191cd855968c136f6ee6e35c16 Mon Sep 17 00:00:00 2001
From: Lzu Tao <taolzu@gmail.com>
Date: Fri, 4 Sep 2020 02:42:50 +0000
Subject: [PATCH] Remove a useless allowed attr

---
 library/core/src/slice/mod.rs   | 1 -
 library/std/src/os/raw/mod.rs   | 1 -
 library/std/src/os/raw/tests.rs | 1 -
 3 files changed, 3 deletions(-)

diff --git a/library/core/src/slice/mod.rs b/library/core/src/slice/mod.rs
index 503f015e76a..4a4cf9cfc17 100644
--- a/library/core/src/slice/mod.rs
+++ b/library/core/src/slice/mod.rs
@@ -66,7 +66,6 @@ impl<T> [T] {
     #[rustc_const_stable(feature = "const_slice_len", since = "1.32.0")]
     #[inline]
     // SAFETY: const sound because we transmute out the length field as a usize (which it must be)
-    #[allow(unused_attributes)]
     #[allow_internal_unstable(const_fn_union)]
     pub const fn len(&self) -> usize {
         // SAFETY: this is safe because `&[T]` and `FatPtr<T>` have the same layout.
diff --git a/library/std/src/os/raw/mod.rs b/library/std/src/os/raw/mod.rs
index 1fe27a34600..83e8853fe79 100644
--- a/library/std/src/os/raw/mod.rs
+++ b/library/std/src/os/raw/mod.rs
@@ -9,7 +9,6 @@
 #![stable(feature = "raw_os", since = "1.1.0")]
 
 #[cfg(test)]
-#[allow(unused_imports)]
 mod tests;
 
 #[doc(include = "char.md")]
diff --git a/library/std/src/os/raw/tests.rs b/library/std/src/os/raw/tests.rs
index e808faf81d6..e7bb7d7e73e 100644
--- a/library/std/src/os/raw/tests.rs
+++ b/library/std/src/os/raw/tests.rs
@@ -1,5 +1,4 @@
 use crate::any::TypeId;
-use crate::mem;
 
 macro_rules! ok {
     ($($t:ident)*) => {$(