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diff --git a/vendor/crossbeam-utils/src/lib.rs b/vendor/crossbeam-utils/src/lib.rs
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+++ b/vendor/crossbeam-utils/src/lib.rs
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+//! Miscellaneous tools for concurrent programming.
+//!
+//! ## Atomics
+//!
+//! * [`AtomicCell`], a thread-safe mutable memory location.
+//! * [`AtomicConsume`], for reading from primitive atomic types with "consume" ordering.
+//!
+//! ## Thread synchronization
+//!
+//! * [`Parker`], a thread parking primitive.
+//! * [`ShardedLock`], a sharded reader-writer lock with fast concurrent reads.
+//! * [`WaitGroup`], for synchronizing the beginning or end of some computation.
+//!
+//! ## Utilities
+//!
+//! * [`Backoff`], for exponential backoff in spin loops.
+//! * [`CachePadded`], for padding and aligning a value to the length of a cache line.
+//! * [`scope`], for spawning threads that borrow local variables from the stack.
+//!
+//! [`AtomicCell`]: atomic::AtomicCell
+//! [`AtomicConsume`]: atomic::AtomicConsume
+//! [`Parker`]: sync::Parker
+//! [`ShardedLock`]: sync::ShardedLock
+//! [`WaitGroup`]: sync::WaitGroup
+//! [`scope`]: thread::scope
+
+#![doc(test(
+    no_crate_inject,
+    attr(
+        deny(warnings, rust_2018_idioms),
+        allow(dead_code, unused_assignments, unused_variables)
+    )
+))]
+#![warn(
+    missing_docs,
+    missing_debug_implementations,
+    rust_2018_idioms,
+    unreachable_pub
+)]
+#![cfg_attr(not(feature = "std"), no_std)]
+
+#[cfg(crossbeam_loom)]
+#[allow(unused_imports)]
+mod primitive {
+    pub(crate) mod sync {
+        pub(crate) mod atomic {
+            pub(crate) use loom::sync::atomic::spin_loop_hint;
+            pub(crate) use loom::sync::atomic::{
+                AtomicBool, AtomicI16, AtomicI32, AtomicI64, AtomicI8, AtomicIsize, AtomicU16,
+                AtomicU32, AtomicU64, AtomicU8, AtomicUsize,
+            };
+
+            // FIXME: loom does not support compiler_fence at the moment.
+            // https://github.com/tokio-rs/loom/issues/117
+            // we use fence as a stand-in for compiler_fence for the time being.
+            // this may miss some races since fence is stronger than compiler_fence,
+            // but it's the best we can do for the time being.
+            pub(crate) use loom::sync::atomic::fence as compiler_fence;
+        }
+        pub(crate) use loom::sync::{Arc, Condvar, Mutex};
+    }
+}
+#[cfg(not(crossbeam_loom))]
+#[allow(unused_imports)]
+mod primitive {
+    pub(crate) mod sync {
+        pub(crate) mod atomic {
+            pub(crate) use core::sync::atomic::compiler_fence;
+            // TODO(taiki-e): once we bump the minimum required Rust version to 1.49+,
+            // use [`core::hint::spin_loop`] instead.
+            #[allow(deprecated)]
+            pub(crate) use core::sync::atomic::spin_loop_hint;
+            #[cfg(not(crossbeam_no_atomic))]
+            pub(crate) use core::sync::atomic::{
+                AtomicBool, AtomicI16, AtomicI32, AtomicI8, AtomicIsize, AtomicU16, AtomicU32,
+                AtomicU8, AtomicUsize,
+            };
+            #[cfg(not(crossbeam_no_atomic_64))]
+            pub(crate) use core::sync::atomic::{AtomicI64, AtomicU64};
+        }
+
+        #[cfg(feature = "std")]
+        pub(crate) use std::sync::{Arc, Condvar, Mutex};
+    }
+}
+
+pub mod atomic;
+
+mod cache_padded;
+pub use crate::cache_padded::CachePadded;
+
+mod backoff;
+pub use crate::backoff::Backoff;
+
+use cfg_if::cfg_if;
+
+cfg_if! {
+    if #[cfg(feature = "std")] {
+        pub mod sync;
+
+        #[cfg(not(crossbeam_loom))]
+        pub mod thread;
+    }
+}