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diff --git a/third_party/abseil_cpp/absl/random/internal/seed_material.h b/third_party/abseil_cpp/absl/random/internal/seed_material.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_SEED_MATERIAL_H_
-#define ABSL_RANDOM_INTERNAL_SEED_MATERIAL_H_
-
-#include <cassert>
-#include <cstdint>
-#include <cstdlib>
-#include <string>
-#include <vector>
-
-#include "absl/base/attributes.h"
-#include "absl/random/internal/fast_uniform_bits.h"
-#include "absl/types/optional.h"
-#include "absl/types/span.h"
-
-namespace absl {
-ABSL_NAMESPACE_BEGIN
-namespace random_internal {
-
-// Returns the number of 32-bit blocks needed to contain the given number of
-// bits.
-constexpr size_t SeedBitsToBlocks(size_t seed_size) {
-  return (seed_size + 31) / 32;
-}
-
-// Amount of entropy (measured in bits) used to instantiate a Seed Sequence,
-// with which to create a URBG.
-constexpr size_t kEntropyBitsNeeded = 256;
-
-// Amount of entropy (measured in 32-bit blocks) used to instantiate a Seed
-// Sequence, with which to create a URBG.
-constexpr size_t kEntropyBlocksNeeded =
-    random_internal::SeedBitsToBlocks(kEntropyBitsNeeded);
-
-static_assert(kEntropyBlocksNeeded > 0,
-              "Entropy used to seed URBGs must be nonzero.");
-
-// Attempts to fill a span of uint32_t-values using an OS-provided source of
-// true entropy (eg. /dev/urandom) into an array of uint32_t blocks of data. The
-// resulting array may be used to initialize an instance of a class conforming
-// to the C++ Standard "Seed Sequence" concept [rand.req.seedseq].
-//
-// If values.data() == nullptr, the behavior is undefined.
-ABSL_MUST_USE_RESULT
-bool ReadSeedMaterialFromOSEntropy(absl::Span<uint32_t> values);
-
-// Attempts to fill a span of uint32_t-values using variates generated by an
-// existing instance of a class conforming to the C++ Standard "Uniform Random
-// Bit Generator" concept [rand.req.urng]. The resulting data may be used to
-// initialize an instance of a class conforming to the C++ Standard
-// "Seed Sequence" concept [rand.req.seedseq].
-//
-// If urbg == nullptr or values.data() == nullptr, the behavior is undefined.
-template <typename URBG>
-ABSL_MUST_USE_RESULT bool ReadSeedMaterialFromURBG(
-    URBG* urbg, absl::Span<uint32_t> values) {
-  random_internal::FastUniformBits<uint32_t> distr;
-
-  assert(urbg != nullptr && values.data() != nullptr);
-  if (urbg == nullptr || values.data() == nullptr) {
-    return false;
-  }
-
-  for (uint32_t& seed_value : values) {
-    seed_value = distr(*urbg);
-  }
-  return true;
-}
-
-// Mixes given sequence of values with into given sequence of seed material.
-// Time complexity of this function is O(sequence.size() *
-// seed_material.size()).
-//
-// Algorithm is based on code available at
-// https://gist.github.com/imneme/540829265469e673d045
-// by Melissa O'Neill.
-void MixIntoSeedMaterial(absl::Span<const uint32_t> sequence,
-                         absl::Span<uint32_t> seed_material);
-
-// Returns salt value.
-//
-// Salt is obtained only once and stored in static variable.
-//
-// May return empty value if optaining the salt was not possible.
-absl::optional<uint32_t> GetSaltMaterial();
-
-}  // namespace random_internal
-ABSL_NAMESPACE_END
-}  // namespace absl
-
-#endif  // ABSL_RANDOM_INTERNAL_SEED_MATERIAL_H_