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diff --git a/third_party/abseil_cpp/absl/random/internal/fastmath.h b/third_party/abseil_cpp/absl/random/internal/fastmath.h
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index 6baeb5a7c917..000000000000
--- a/third_party/abseil_cpp/absl/random/internal/fastmath.h
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-// 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_RANDOM_INTERNAL_FASTMATH_H_
-#define ABSL_RANDOM_INTERNAL_FASTMATH_H_
-
-// This file contains fast math functions (bitwise ops as well as some others)
-// which are implementation details of various absl random number distributions.
-
-#include <cassert>
-#include <cmath>
-#include <cstdint>
-
-#include "absl/base/internal/bits.h"
-
-namespace absl {
-ABSL_NAMESPACE_BEGIN
-namespace random_internal {
-
-// Returns the position of the first bit set.
-inline int LeadingSetBit(uint64_t n) {
-  return 64 - base_internal::CountLeadingZeros64(n);
-}
-
-// Compute log2(n) using integer operations.
-// While std::log2 is more accurate than std::log(n) / std::log(2), for
-// very large numbers--those close to std::numeric_limits<uint64_t>::max() - 2,
-// for instance--std::log2 rounds up rather than down, which introduces
-// definite skew in the results.
-inline int IntLog2Floor(uint64_t n) {
-  return (n <= 1) ? 0 : (63 - base_internal::CountLeadingZeros64(n));
-}
-inline int IntLog2Ceil(uint64_t n) {
-  return (n <= 1) ? 0 : (64 - base_internal::CountLeadingZeros64(n - 1));
-}
-
-inline double StirlingLogFactorial(double n) {
-  assert(n >= 1);
-  // Using Stirling's approximation.
-  constexpr double kLog2PI = 1.83787706640934548356;
-  const double logn = std::log(n);
-  const double ninv = 1.0 / static_cast<double>(n);
-  return n * logn - n + 0.5 * (kLog2PI + logn) + (1.0 / 12.0) * ninv -
-         (1.0 / 360.0) * ninv * ninv * ninv;
-}
-
-// Rotate value right.
-//
-// We only implement the uint32_t / uint64_t versions because
-// 1) those are the only ones we use, and
-// 2) those are the only ones where clang detects the rotate idiom correctly.
-inline constexpr uint32_t rotr(uint32_t value, uint8_t bits) {
-  return (value >> (bits & 31)) | (value << ((-bits) & 31));
-}
-inline constexpr uint64_t rotr(uint64_t value, uint8_t bits) {
-  return (value >> (bits & 63)) | (value << ((-bits) & 63));
-}
-
-}  // namespace random_internal
-ABSL_NAMESPACE_END
-}  // namespace absl
-
-#endif  // ABSL_RANDOM_INTERNAL_FASTMATH_H_