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diff --git a/third_party/abseil_cpp/absl/base/internal/atomic_hook.h b/third_party/abseil_cpp/absl/base/internal/atomic_hook.h
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index ae21cd7fe50a..000000000000
--- a/third_party/abseil_cpp/absl/base/internal/atomic_hook.h
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@@ -1,200 +0,0 @@
-// Copyright 2017 The Abseil Authors.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//      https://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-#ifndef ABSL_BASE_INTERNAL_ATOMIC_HOOK_H_
-#define ABSL_BASE_INTERNAL_ATOMIC_HOOK_H_
-
-#include <atomic>
-#include <cassert>
-#include <cstdint>
-#include <utility>
-
-#include "absl/base/attributes.h"
-#include "absl/base/config.h"
-
-#if defined(_MSC_VER) && !defined(__clang__)
-#define ABSL_HAVE_WORKING_CONSTEXPR_STATIC_INIT 0
-#else
-#define ABSL_HAVE_WORKING_CONSTEXPR_STATIC_INIT 1
-#endif
-
-#if defined(_MSC_VER)
-#define ABSL_HAVE_WORKING_ATOMIC_POINTER 0
-#else
-#define ABSL_HAVE_WORKING_ATOMIC_POINTER 1
-#endif
-
-namespace absl {
-ABSL_NAMESPACE_BEGIN
-namespace base_internal {
-
-template <typename T>
-class AtomicHook;
-
-// To workaround AtomicHook not being constant-initializable on some platforms,
-// prefer to annotate instances with `ABSL_INTERNAL_ATOMIC_HOOK_ATTRIBUTES`
-// instead of `ABSL_CONST_INIT`.
-#if ABSL_HAVE_WORKING_CONSTEXPR_STATIC_INIT
-#define ABSL_INTERNAL_ATOMIC_HOOK_ATTRIBUTES ABSL_CONST_INIT
-#else
-#define ABSL_INTERNAL_ATOMIC_HOOK_ATTRIBUTES
-#endif
-
-// `AtomicHook` is a helper class, templatized on a raw function pointer type,
-// for implementing Abseil customization hooks.  It is a callable object that
-// dispatches to the registered hook.  Objects of type `AtomicHook` must have
-// static or thread storage duration.
-//
-// A default constructed object performs a no-op (and returns a default
-// constructed object) if no hook has been registered.
-//
-// Hooks can be pre-registered via constant initialization, for example:
-//
-// ABSL_INTERNAL_ATOMIC_HOOK_ATTRIBUTES static AtomicHook<void(*)()>
-//     my_hook(DefaultAction);
-//
-// and then changed at runtime via a call to `Store()`.
-//
-// Reads and writes guarantee memory_order_acquire/memory_order_release
-// semantics.
-template <typename ReturnType, typename... Args>
-class AtomicHook<ReturnType (*)(Args...)> {
- public:
-  using FnPtr = ReturnType (*)(Args...);
-
-  // Constructs an object that by default performs a no-op (and
-  // returns a default constructed object) when no hook as been registered.
-  constexpr AtomicHook() : AtomicHook(DummyFunction) {}
-
-  // Constructs an object that by default dispatches to/returns the
-  // pre-registered default_fn when no hook has been registered at runtime.
-#if ABSL_HAVE_WORKING_ATOMIC_POINTER && ABSL_HAVE_WORKING_CONSTEXPR_STATIC_INIT
-  explicit constexpr AtomicHook(FnPtr default_fn)
-      : hook_(default_fn), default_fn_(default_fn) {}
-#elif ABSL_HAVE_WORKING_CONSTEXPR_STATIC_INIT
-  explicit constexpr AtomicHook(FnPtr default_fn)
-      : hook_(kUninitialized), default_fn_(default_fn) {}
-#else
-  // As of January 2020, on all known versions of MSVC this constructor runs in
-  // the global constructor sequence.  If `Store()` is called by a dynamic
-  // initializer, we want to preserve the value, even if this constructor runs
-  // after the call to `Store()`.  If not, `hook_` will be
-  // zero-initialized by the linker and we have no need to set it.
-  // https://developercommunity.visualstudio.com/content/problem/336946/class-with-constexpr-constructor-not-using-static.html
-  explicit constexpr AtomicHook(FnPtr default_fn)
-      : /* hook_(deliberately omitted), */ default_fn_(default_fn) {
-    static_assert(kUninitialized == 0, "here we rely on zero-initialization");
-  }
-#endif
-
-  // Stores the provided function pointer as the value for this hook.
-  //
-  // This is intended to be called once.  Multiple calls are legal only if the
-  // same function pointer is provided for each call.  The store is implemented
-  // as a memory_order_release operation, and read accesses are implemented as
-  // memory_order_acquire.
-  void Store(FnPtr fn) {
-    bool success = DoStore(fn);
-    static_cast<void>(success);
-    assert(success);
-  }
-
-  // Invokes the registered callback.  If no callback has yet been registered, a
-  // default-constructed object of the appropriate type is returned instead.
-  template <typename... CallArgs>
-  ReturnType operator()(CallArgs&&... args) const {
-    return DoLoad()(std::forward<CallArgs>(args)...);
-  }
-
-  // Returns the registered callback, or nullptr if none has been registered.
-  // Useful if client code needs to conditionalize behavior based on whether a
-  // callback was registered.
-  //
-  // Note that atomic_hook.Load()() and atomic_hook() have different semantics:
-  // operator()() will perform a no-op if no callback was registered, while
-  // Load()() will dereference a null function pointer.  Prefer operator()() to
-  // Load()() unless you must conditionalize behavior on whether a hook was
-  // registered.
-  FnPtr Load() const {
-    FnPtr ptr = DoLoad();
-    return (ptr == DummyFunction) ? nullptr : ptr;
-  }
-
- private:
-  static ReturnType DummyFunction(Args...) {
-    return ReturnType();
-  }
-
-  // Current versions of MSVC (as of September 2017) have a broken
-  // implementation of std::atomic<T*>:  Its constructor attempts to do the
-  // equivalent of a reinterpret_cast in a constexpr context, which is not
-  // allowed.
-  //
-  // This causes an issue when building with LLVM under Windows.  To avoid this,
-  // we use a less-efficient, intptr_t-based implementation on Windows.
-#if ABSL_HAVE_WORKING_ATOMIC_POINTER
-  // Return the stored value, or DummyFunction if no value has been stored.
-  FnPtr DoLoad() const { return hook_.load(std::memory_order_acquire); }
-
-  // Store the given value.  Returns false if a different value was already
-  // stored to this object.
-  bool DoStore(FnPtr fn) {
-    assert(fn);
-    FnPtr expected = default_fn_;
-    const bool store_succeeded = hook_.compare_exchange_strong(
-        expected, fn, std::memory_order_acq_rel, std::memory_order_acquire);
-    const bool same_value_already_stored = (expected == fn);
-    return store_succeeded || same_value_already_stored;
-  }
-
-  std::atomic<FnPtr> hook_;
-#else  // !ABSL_HAVE_WORKING_ATOMIC_POINTER
-  // Use a sentinel value unlikely to be the address of an actual function.
-  static constexpr intptr_t kUninitialized = 0;
-
-  static_assert(sizeof(intptr_t) >= sizeof(FnPtr),
-                "intptr_t can't contain a function pointer");
-
-  FnPtr DoLoad() const {
-    const intptr_t value = hook_.load(std::memory_order_acquire);
-    if (value == kUninitialized) {
-      return default_fn_;
-    }
-    return reinterpret_cast<FnPtr>(value);
-  }
-
-  bool DoStore(FnPtr fn) {
-    assert(fn);
-    const auto value = reinterpret_cast<intptr_t>(fn);
-    intptr_t expected = kUninitialized;
-    const bool store_succeeded = hook_.compare_exchange_strong(
-        expected, value, std::memory_order_acq_rel, std::memory_order_acquire);
-    const bool same_value_already_stored = (expected == value);
-    return store_succeeded || same_value_already_stored;
-  }
-
-  std::atomic<intptr_t> hook_;
-#endif
-
-  const FnPtr default_fn_;
-};
-
-#undef ABSL_HAVE_WORKING_ATOMIC_POINTER
-#undef ABSL_HAVE_WORKING_CONSTEXPR_STATIC_INIT
-
-}  // namespace base_internal
-ABSL_NAMESPACE_END
-}  // namespace absl
-
-#endif  // ABSL_BASE_INTERNAL_ATOMIC_HOOK_H_